Sample records for leaderless enterocin l50
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Criado, Raquel; Gutiérrez, Jorge; Martín, María; Herranz, Carmen; Hernández, Pablo E; Cintas, Luis M
2006-12-01
Polyclonal antibodies with specificity for enterocin L50A (EntL50A), enterocin L50B (EntL50B), and enterocin Q (EntQ) produced by Enterococcus faecium L50 have been generated by immunization of rabbits with chemically synthesized peptides derived from the C terminus of EntL50A (LR1) and EntL50B (LR2) and from the complete enterocin Q (EntQ) conjugated to the carrier protein keyhole limpet hemocyanin (KLH). The sensitivity and specificity of these antibodies were evaluated by a noncompetitive indirect enzyme-linked immunosorbent assay (NCI-ELISA) and a competitive indirect ELISA (CI-ELISA). The NCI-ELISA was valuable for detecting anti-EntL50A-, anti-EntL50B-, and anti-EntQ-specific antibodies in the sera of the LR1-KLH-, LR2-KLH-, and EntQ-KLH-immunized animals, respectively. Moreover, these antibodies and those specific for enterocin P (EntP) obtained in a previous work (J. Gutiérrez, R. Criado, R. Citti, M. Martín, C. Herranz, M. F. Fernández, L. M. Cintas, and P. E. Hernández, J. Agric. Food Chem. 52:2247-2255, 2004) were used in an NCI-ELISA to detect and quantify the production of EntL50A, EntL50B, EntP, and EntQ by the multiple-bacteriocin producer E. faecium L50 grown at different temperatures (16 to 47 degrees C). Our results show that temperature has a strong influence on bacteriocin production by this strain. EntL50A and EntL50B are synthesized at 16 to 32 degrees C, but production becomes negligible when the growth temperature is above 37 degrees C, whereas EntP and EntQ are synthesized at temperatures ranging from 16 to 47 degrees C. Maximum EntL50A and EntL50B production was detected at 25 degrees C, while EntP and EntQ are maximally produced at 37 and 47 degrees C, respectively. The loss of plasmid pCIZ1 (50 kb) and/or pCIZ2 (7.4 kb), encoding EntL50A and EntL50B as well as EntQ, respectively, resulted in a significant increase in production and stability of the chromosomally encoded EntP.
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Caly, Delphine L; Chevalier, Mickaël; Flahaut, Christophe; Cudennec, Benoit; Al Atya, Ahmed Khassaf; Chataigné, Gabrielle; D'Inca, Romain; Auclair, Eric; Drider, Djamel
2017-03-01
Enterococcus faecalis 14, a strain previously isolated from meconium, displayed activity against four Clostridium perfringens isolates when co-cultured on agar plates. The anti-Clostridium activity was ascribed to the production of enterocin DD14, which was subsequently purified. The minimum inhibitory concentration (MIC) of enterocin DD14 against one collection strain and one clinical C. perfringens strain was determined at 50 µg/mL. Furthermore, using the intestinal epithelial cell line IPEC-1, it was shown that E. faecalis 14 was not cytotoxic after 24 h of contact, and no cytotoxicity was observed when IPEC-1 cells were incubated with pure enterocin DD14 for 4 h. Enterocin DD14 was characterised using mass spectrometry and was shown to consist of two small proteins of 5200.74 Da and 5206.41 Da, respectively. The two peptides (DD14A and DD14B) have highly similar amino acid sequences and no signal peptide, which classifies enterocin DD14 as a class IIb leaderless two-peptide bacteriocin. The genes encoding DD14A and DD14B were sequenced and were shown to be 100% identical to other previously described enterocins MR10A and MR10B, in contrast to the producing strains, which are different. Consequently, the present in vitro study supports the potential of this E. faecalis 14 strain and/or its purified enterocin DD14 as putative anti-C. perfringens compounds in chickens. Copyright © 2017. Published by Elsevier B.V.
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Izquierdo, Esther; Bednarczyk, Audrey; Schaeffer, Christine; Cai, Yimin; Marchioni, Eric; Van Dorsselaer, Alain; Ennahar, Saïd
2008-01-01
Enterococcus faecium IT62, isolated from ryegrass in Japan, was shown to produce three different bacteriocins, two of which had molecular masses and amino acid sequences that corresponded to those of enterocin L50A and enterocin L50B. These peptides existed, however, as chemically modified forms that were either N formylated or N formylated and oxidized at Met24. The third bacteriocin, named enterocin IT, had a molecular mass of 6,390 Da, was made up of 54 amino acids, and did not correspond to any known bacteriocin. However, enterocin IT was identical to the C-terminal part of the 16-amino-acid-longer bacteriocin 32 (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). For the first time, the antimicrobial activity spectra for enterocins L50A and L50B were determined separately and included a wide range of gram-positive bacteria but also a few gram-negative strains that were weakly sensitive. Slight differences in the activities of enterocins L50A and L50B were observed, as gram-positive bacteria showed an overall higher level of sensitivity to L50A than to L50B, as opposed to gram-negative ones. Conversely, enterocin IT showed a very narrow antimicrobial spectrum that was limited to E. faecium strains, one strain of Bacillus subtilis, and one strain of Lactococcus lactis. This study showed that E. faecium IT62, a grass-borne strain, produces bacteriocins with very different activity features and structures that may be found in strains associated with food or those of clinical origin, which demonstrates that a particular enterocin structure may be widespread and not related to the producer's origin. PMID:18391036
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Izquierdo, Esther; Bednarczyk, Audrey; Schaeffer, Christine; Cai, Yimin; Marchioni, Eric; Van Dorsselaer, Alain; Ennahar, Saïd
2008-06-01
Enterococcus faecium IT62, isolated from ryegrass in Japan, was shown to produce three different bacteriocins, two of which had molecular masses and amino acid sequences that corresponded to those of enterocin L50A and enterocin L50B. These peptides existed, however, as chemically modified forms that were either N formylated or N formylated and oxidized at Met(24). The third bacteriocin, named enterocin IT, had a molecular mass of 6,390 Da, was made up of 54 amino acids, and did not correspond to any known bacteriocin. However, enterocin IT was identical to the C-terminal part of the 16-amino-acid-longer bacteriocin 32 (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). For the first time, the antimicrobial activity spectra for enterocins L50A and L50B were determined separately and included a wide range of gram-positive bacteria but also a few gram-negative strains that were weakly sensitive. Slight differences in the activities of enterocins L50A and L50B were observed, as gram-positive bacteria showed an overall higher level of sensitivity to L50A than to L50B, as opposed to gram-negative ones. Conversely, enterocin IT showed a very narrow antimicrobial spectrum that was limited to E. faecium strains, one strain of Bacillus subtilis, and one strain of Lactococcus lactis. This study showed that E. faecium IT62, a grass-borne strain, produces bacteriocins with very different activity features and structures that may be found in strains associated with food or those of clinical origin, which demonstrates that a particular enterocin structure may be widespread and not related to the producer's origin.
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Lohans, Christopher T; Towle, Kaitlyn M; Miskolzie, Mark; McKay, Ryan T; van Belkum, Marco J; McMullen, Lynn M; Vederas, John C
2013-06-11
Leaderless bacteriocins are a class of ribosomally synthesized antimicrobial peptides that are produced by certain Gram-positive bacteria without an N-terminal leader section. These bacteriocins are of great interest due to their potent inhibition of many Gram-positive organisms, including food-borne pathogens such as Listeria and Clostridium spp. We now report the NMR solution structures of enterocins 7A and 7B, leaderless bacteriocins recently isolated from Enterococcus faecalis 710C. These are the first three-dimensional structures to be reported for bacteriocins of this class. Unlike most other linear Gram-positive bacteriocins, enterocins 7A and 7B are highly structured in aqueous conditions. Both peptides are primarily α-helical, adopting a similar overall fold. The structures can be divided into three separate α-helical regions: the N- and C-termini are both α-helical, separated by a central kinked α-helix. The overall structures bear an unexpected resemblance to carnocyclin A, a 60-residue peptide that is cyclized via an amide bond between the C- and N-termini and has a saposin fold. Because of synergism observed for other two-peptide leaderless bacteriocins, it was of interest to probe possible binding interactions between enterocins 7A and 7B. However, despite synergistic activity observed between these peptides, no significant binding interaction was observed based on NMR and isothermal calorimetry.
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Cintas, Luis M.; Casaus, Pilar; Herranz, Carmen; Håvarstein, Leiv Sigve; Holo, Helge; Hernández, Pablo E.; Nes, Ingolf F.
2000-01-01
Enterococcus faecium L50 grown at 16 to 32°C produces enterocin L50 (EntL50), consisting of EntL50A and EntL50B, two unmodified non-pediocin-like peptides synthesized without an N-terminal leader sequence or signal peptide. However, the bacteriocin activity found in the cell-free culture supernatants following growth at higher temperatures (37 to 47°C) is not due to EntL50. A purification procedure including cation-exchange, hydrophobic interaction, and reverse-phase liquid chromatography has shown that the antimicrobial activity is due to two different bacteriocins. Amino acid sequences obtained by Edman degradation and DNA sequencing analyses revealed that one is identical to the sec-dependent pediocin-like enterocin P produced by E. faecium P13 (L. M. Cintas, P. Casaus, L. S. Håvarstein, P. E. Hernández, and I. F. Nes, Appl. Environ. Microbiol. 63:4321–4330, 1997) and the other is a novel unmodified non-pediocin-like bacteriocin termed enterocin Q (EntQ), with a molecular mass of 3,980. DNA sequencing analysis of a 963-bp region of E. faecium L50 containing the enterocin P structural gene (entP) and the putative immunity protein gene (entiP) reveals a genetic organization identical to that previously found in E. faecium P13. DNA sequencing analysis of a 1,448-bp region identified two consecutive but diverging open reading frames (ORFs) of which one, termed entQ, encodes a 34-amino-acid protein whose deduced amino acid sequence was identical to that obtained for EntQ by amino acid sequencing, showing that EntQ, similarly to EntL50A and EntL50B, is synthesized without an N-terminal leader sequence or signal peptide. The second ORF, termed orf2, was located immediately upstream of and in opposite orientation to entQ and encodes a putative immunity protein composed of 221 amino acids. Bacteriocin production by E. faecium L50 showed that EntP and EntQ are produced in the temperature range from 16 to 47°C and maximally detected at 47 and 37 to 47
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Occurrence of the structural enterocin A, P, B, L50B genes in enterococci of different origin.
Strompfová, Viola; Lauková, Andrea; Simonová, Monika; Marcináková, Miroslava
2008-12-10
Enterococci are well-known producers of antimicrobial peptides--bacteriocins (enterocins) and the number of characterized enterocins has been significantly increased. Recently, enterocins are of great interest for their potential as biopreservatives in food or feed while research on enterocins as alternative antimicrobials in humans and animals is only at the beginning. The present study provides a survey about the occurrence of enterocin structural genes A, P, B, L50B in a target of 427 strains of Enterococcus faecium (368) and Enterococcus faecalis (59) species from different sources (animal isolates, food and feed) performed by PCR method. Based on our results, 234 strains possessed one or more enterocin structural gene(s). The genes of enterocin P and enterocin A were the most frequently detected structural genes among the PCR positive strains (170 and 155 strains, respectively). Different frequency of the enterocin genes occurrence was detected in strains according to their origin; the strains from horses and silage showed the highest frequency of enterocin genes presence. All possible combinations of the tested genes occurred at least twice except the combination of the gene of enterocin B and L50B which possessed neither strain. The gene of enterocin A was exclusively detected among E. faecium strains, while the gene of enterocin P, B, L50B were detected in strains of both species E. faecium and E. faecalis. In conclusion, a high-frequency and variability of enterocin structural genes exists among enterococci of different origin what offers a big possibility to find effective bacteriocin-producing strains for their application in veterinary medicine.
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Sandra Mojsova; Kiril Krstevski; Igor Dzadzovski; Zagorka Popova; Pavle Sekulovski
2015-01-01
The study investigated the antimicrobial activity of 13 enterococcal strains (E. faecalis -8, E. faecium-2, E. hirae-2, E. spp.-1) isolated from our traditional cheeses against pathogen microorganisms. Also, it includes the detection of the following enterocin structural genes: enterocin A, enterocin B, enterocin P, enterocin L50A/B, bacteriocin 31, enterocin AS48, enterocin Q, enterocin EJ97 and cytolysin by using PCR method. All isolates inhibited growth of L. monocytogenes and L.innocua...
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Ovchinnikov, Kirill V; Kristiansen, Per Eugen; Straume, Daniel; Jensen, Marianne S; Aleksandrzak-Piekarczyk, Tamara; Nes, Ingolf F; Diep, Dzung B
2017-01-01
Enterocin K1 (EntK1), enterocin EJ97 (EntEJ97), and LsbB are three sequence related leaderless bacteriocins. Yet LsbB kills only lactococci while EntK1 and EntEJ97 target wider spectra with EntK1 being particularly active against Enterococcus faecium , including nosocomial multidrug resistant isolates. NMR study of EntK1 showed that it had a structure very similar to LsbB - both having an amphiphilic N-terminal α-helix and an unstructured C-terminus. The α-helix in EntK1 is, however, about 3-4 residues longer than that of LsbB. Enterococcal mutants highly resistant to EntEJ97 and EntK1 were found to have mutations within rseP , a gene encoding a stress response membrane-bound Zn-dependent protease. Heterologous expression of the enterococcal rseP rendered resistant cells of Streptococcus pneumoniae sensitive to EntK1 and EntEJ97, suggesting that RseP likely serves as the receptor for EntK1 and EntEJ97. It was also shown that the conserved proteolytic active site in E. faecalis RseP is partly required for EntK1 and EntEJ97 activity, since alanine substitutions of its conserved residues (HExxH) reduced the sensitivity of the clones to the bacteriocins. RseP is known to be involved in bacterial stress response. As expected, the growth of resistant mutants with mutations within rseP was severely affected when they were exposed to higher (stressing) growth temperatures, e.g., at 45°C, at which wild type cells still grew well. These findings allow us to design a hurdle strategy with a combination of the bacteriocin(s) and higher temperature that effectively kills bacteriocin sensitive bacteria and prevents the development of resistant cells.
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Kirill V. Ovchinnikov
2017-05-01
Full Text Available Enterocin K1 (EntK1, enterocin EJ97 (EntEJ97, and LsbB are three sequence related leaderless bacteriocins. Yet LsbB kills only lactococci while EntK1 and EntEJ97 target wider spectra with EntK1 being particularly active against Enterococcus faecium, including nosocomial multidrug resistant isolates. NMR study of EntK1 showed that it had a structure very similar to LsbB – both having an amphiphilic N-terminal α-helix and an unstructured C-terminus. The α-helix in EntK1 is, however, about 3–4 residues longer than that of LsbB. Enterococcal mutants highly resistant to EntEJ97 and EntK1 were found to have mutations within rseP, a gene encoding a stress response membrane-bound Zn-dependent protease. Heterologous expression of the enterococcal rseP rendered resistant cells of Streptococcus pneumoniae sensitive to EntK1 and EntEJ97, suggesting that RseP likely serves as the receptor for EntK1 and EntEJ97. It was also shown that the conserved proteolytic active site in E. faecalis RseP is partly required for EntK1 and EntEJ97 activity, since alanine substitutions of its conserved residues (HExxH reduced the sensitivity of the clones to the bacteriocins. RseP is known to be involved in bacterial stress response. As expected, the growth of resistant mutants with mutations within rseP was severely affected when they were exposed to higher (stressing growth temperatures, e.g., at 45°C, at which wild type cells still grew well. These findings allow us to design a hurdle strategy with a combination of the bacteriocin(s and higher temperature that effectively kills bacteriocin sensitive bacteria and prevents the development of resistant cells.
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Sandra Mojsova
2015-10-01
Full Text Available The study investigated the antimicrobial activity of 13 enterococcal strains (E. faecalis -8, E. faecium-2, E. hirae-2, E. spp.-1 isolated from our traditional cheeses against pathogen microorganisms. Also, it includes the detection of the following enterocin structural genes: enterocin A, enterocin B, enterocin P, enterocin L50A/B, bacteriocin 31, enterocin AS48, enterocin Q, enterocin EJ97 and cytolysin by using PCR method. All isolates inhibited growth of L. monocytogenes and L.innocua. One isolate had a broader antimicrobial activity. None of the isolates showed inhibitory activity against S. enteritidis, E. coli and Y. enterocolitica. The genes enterocin P, cytolysin and enterocin A were the most frequently detected structural genes among the PCR positive strains. No amplification was obtained in two strains E. faecalis-25 and E. faecalis-86. Three different genes were identified in some strains. With the exclusion of strains possessing a virulence factor, such as cytolysin, producers of more than one enterocins could be of a great technological potential as protective cultures in the cheese industry.
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Screening of the Enterocin-Encoding Genes and Antimicrobial Activity in Enterococcus Species.
Ogaki, Mayara Baptistucci; Rocha, Katia Real; Terra, MÁrcia Regina; Furlaneto, MÁrcia Cristina; Maia, Luciana Furlaneto
2016-06-28
In the current study, a total of 135 enterococci strains from different sources were screened for the presence of the enterocin-encoding genes entA, entP, entB, entL50A, and entL50B. The enterocin genes were present at different frequencies, with entA occurring the most frequently, followed by entP and entB; entL50A and L50B were not detected. The occurrence of single enterocin genes was higher than the occurrence of multiple enterocin gene combinations. The 80 isolates that harbor at least one enterocin-encoding gene (denoted "Gene(+) strains") were screened for antimicrobial activity. A total of 82.5% of the Gene(+) strains inhibited at least one of the indicator strains, and the isolates harboring multiple enterocin-encoding genes inhibited a larger number of indicator strains than isolates harboring a single gene. The indicator strains that exhibited growth inhibition included Listeria innocua strain CLIP 12612 (ATCC BAA-680), Listeria monocytogenes strain CDC 4555, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, S. aureus ATCC 29213, S. aureus ATCC 6538, Salmonella enteritidis ATCC 13076, Salmonella typhimurium strain UK-1 (ATCC 68169), and Escherichia coli BAC 49LT ETEC. Inhibition due to either bacteriophage lysis or cytolysin activity was excluded. The growth inhibition of antilisterial Gene+ strains was further tested under different culture conditions. Among the culture media formulations, the MRS agar medium supplemented with 2% (w/v) yeast extract was the best solidified medium for enterocin production. Our findings extend the current knowledge of enterocin-producing enterococci, which may have potential applications as biopreservatives in the food industry due to their capability of controlling food spoilage pathogens.
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Tiwari, Santosh Kumar; Sutyak Noll, Katia; Cavera, Veronica L; Chikindas, Michael L
2015-03-01
Two hybrid bacteriocins, enterocin E50-52/pediocin PA-1 (EP) and pediocin PA-1/enterocin E50-52 (PE), were designed by combining the N terminus of enterocin E50-52 and the C terminus of pediocin PA-1 and by combining the C terminus of pediocin PA-1 and the N terminus of enterocin E50-52, respectively. Both hybrid bacteriocins showed reduced MICs compared to those of their natural counterparts. The MICs of hybrid PE and EP were 64- and 32-fold lower, respectively, than the MIC of pediocin PA-1 and 8- and 4-fold lower, respectively, than the MIC of enterocin E50-52. In this study, the effect of hybrid as well as wild-type (WT) bacteriocins on the transmembrane electrical potential (ΔΨ) and their ability to induce the efflux of intracellular ATP were investigated. Enterocin E50-52, pediocin PA-1, and hybrid bacteriocin PE were able to dissipate ΔΨ, but EP was unable to deplete this component. Both hybrid bacteriocins caused a loss of the intracellular concentration of ATP. EP, however, caused a faster efflux than PE and enterocin E50-52. Enterocin E50-52 and hybrids PE and EP were active against the Gram-positive and Gram-negative bacteria tested, such as Micrococcus luteus, Salmonella enterica serovar Enteritidis 20E1090, and Escherichia coli O157:H7. The hybrid bacteriocins designed and described herein are antimicrobial peptides with MICs lower those of their natural counterparts. Both hybrid peptides induce the loss of intracellular ATP and are capable of inhibiting Gram-negative bacteria, and PE dissipates the electrical potential. In this study, the MIC of hybrid bacteriocin PE decreased 64-fold compared to the MIC of its natural peptide counterpart, pediocin PA-1. Inhibition of Gram-negative pathogens confers an additional advantage for the application of these peptides in therapeutics. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
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Izquierdo, Esther; Cai, Yimin; Marchioni, Eric; Ennahar, Saïd
2009-05-01
Enterococcus faecium IT62, a strain isolated from ryegrass in Japan, produces three bacteriocins (enterocins L50A, L50B, and IT) that have been previously purified and the primary structures of which have been determined by amino acid sequencing (E. Izquierdo, A. Bednarczyk, C. Schaeffer, Y. Cai, E. Marchioni, A. Van Dorsselaer, and S. Ennahar, Antimicrob. Agents Chemother., 52:1917-1923, 2008). Genetic analysis showed that the bacteriocins of E. faecium IT62 are plasmid encoded, but with the structural genes specifying enterocin L50A and enterocin L50B being carried by a plasmid (pTAB1) that is separate from the one (pTIT1) carrying the structural gene of enterocin IT. Sequencing analysis of a 1,475-bp region from pTAB1 identified two consecutive open reading frames corresponding, with the exception of 2 bp, to the genes entL50A and entL50B, encoding EntL50A and EntL50B, respectively. Both bacteriocins are synthesized without N-terminal leader sequences. Genetic analysis of a sequenced 1,380-bp pTIT1 fragment showed that the genes entIT and entIM, encoding enterocin IT and its immunity protein, respectively, were both found in E. faecium VRE200 for bacteriocin 32. Enterocin IT, a 6,390-Da peptide made up of 54 amino acids, has been previously shown to be identical to the C-terminal part of bacteriocin 32, a 7,998-Da bacteriocin produced by E. faecium VRE200 whose structure was deduced from its structural gene (T. Inoue, H. Tomita, and Y. Ike, Antimicrob. Agents Chemother., 50:1202-1212, 2006). By combining the biochemical and genetic data on enterocin IT, it was concluded that bacteriocin 32 is in fact identical to enterocin IT, both being encoded by the same plasmid-borne gene, and that the N-terminal leader peptide for this bacteriocin is 35 amino acids long and not 19 amino acids long as previously reported.
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Salvucci, E; Hebert, E M; Sesma, F; Saavedra, L
2010-08-01
To evaluate the inhibition effectiveness of enterocin CRL35 in combination with cell wall, membrane-acting antibiotics and muranolytic enzymes against the foodborne pathogen Listeria. Synthetic enterocin CRL35 alone and in combination with monensin, bacitracin, gramicidin, mutanolysin and lysozyme were used in this study. Minimal inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) index assays were performed using Listeria innocua 7 and Listeria monocytogenes FBUNT as sensitive strains. Antibiotics showed positive interactions with the bacteriocin in both strains tested. On the other hand, when mutanolysin and enterocin CRL35 were added to resting cells in a buffer system, the lytic effect of mutanolysin was enhanced. However, the addition of mutanolysin showed no effect on the growth of L. innocua 7 cells in a culture medium. Moreover, mutanolysin allowed the overgrowth of L. innocua 7 cells to an OD similar to control cells in the presence of inhibitory concentration of enterocin CRL35. In contrast, the combination of lysozyme and enterocin CRL35 resulted in a 50% inhibition of the L. innocua 7 growth. Based on our results, we conclude that the combination of synthetic enterocin CRL35 with some antibiotics is effective against L. innocua 7 and L. monocytogenes FBUNT cells, and more importantly the amount of these agents to be used was considerably reduced. The effectiveness of the combination of synthetic enterocin CRL35 with muramidases seems to depend on complex environments, and more detailed studies need to be performed to elucidate this issue. Enterocin CRL35 represents a promising agent that not only can ensure the quality and safety of food but it can also be combined with several antimicrobial agents important in the medical field.
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Characterization and application of enterocin RM6, a bacteriocin from Enterococcus faecalis.
Huang, En; Zhang, Liwen; Chung, Yoon-Kyung; Zheng, Zuoxing; Yousef, Ahmed E
2013-01-01
Use of bacteriocins in food preservation has received great attention in recent years. The goal of this study is to characterize enterocin RM6 from Enterococcus faecalis OSY-RM6 and investigate its efficacy against Listeria monocytogenes in cottage cheese. Enterocin RM6 was purified from E. faecalis culture supernatant using ion exchange column, multiple C18-silica cartridges, followed by reverse-phase high-performance liquid chromatography. The molecular weight of enterocin RM6 is 7145.0823 as determined by mass spectrometry (MS). Tandem mass spectrometry (MS/MS) analysis revealed that enterocin RM6 is a 70-residue cyclic peptide with a head-to-tail linkage between methionine and tryptophan residues. The peptide sequence of enterocin RM6 was further confirmed by sequencing the structural gene of the peptide. Enterocin RM6 is active against Gram-positive bacteria, including L. monocytogenes, Bacillus cereus, and methicillin-resistant Staphylococcus aureus (MRSA). Enterocin RM6 (final concentration in cottage cheese, 80 AU/mL) caused a 4-log reduction in population of L. monocytogenes inoculated in cottage cheese within 30 min of treatment. Therefore, enterocin RM6 has potential applications as a potent antimicrobial peptide against foodborne pathogens in food.
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Characterization and Application of Enterocin RM6, a Bacteriocin from Enterococcus faecalis
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En Huang
2013-01-01
Full Text Available Use of bacteriocins in food preservation has received great attention in recent years. The goal of this study is to characterize enterocin RM6 from Enterococcus faecalis OSY-RM6 and investigate its efficacy against Listeria monocytogenes in cottage cheese. Enterocin RM6 was purified from E. faecalis culture supernatant using ion exchange column, multiple C18-silica cartridges, followed by reverse-phase high-performance liquid chromatography. The molecular weight of enterocin RM6 is 7145.0823 as determined by mass spectrometry (MS. Tandem mass spectrometry (MS/MS analysis revealed that enterocin RM6 is a 70-residue cyclic peptide with a head-to-tail linkage between methionine and tryptophan residues. The peptide sequence of enterocin RM6 was further confirmed by sequencing the structural gene of the peptide. Enterocin RM6 is active against Gram-positive bacteria, including L. monocytogenes, Bacillus cereus, and methicillin-resistant Staphylococcus aureus (MRSA. Enterocin RM6 (final concentration in cottage cheese, 80 AU/mL caused a 4-log reduction in population of L. monocytogenes inoculated in cottage cheese within 30 min of treatment. Therefore, enterocin RM6 has potential applications as a potent antimicrobial peptide against foodborne pathogens in food.
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Kalaitzis, John A; Cheng, Qian; Meluzzi, Dario; Xiang, Longkuan; Izumikawa, Miho; Dorrestein, Pieter C; Moore, Bradley S
2011-11-15
Enterocin is an atypical type II polyketide synthase (PKS) product from the marine actinomycete 'Streptomyces maritimus'. The enterocin biosynthesis gene cluster (enc) codes for proteins involved in the assembly and attachment of the rare benzoate primer that initiates polyketide assembly with the addition of seven malonate molecules and culminates in a Favorskii-like rearrangement of the linear poly-β-ketone to give its distinctive non-aromatic, caged core structure. Fundamental to enterocin biosynthesis, which utilizes a single acyl carrier protein (ACP), EncC, for both priming with benzoate and elongating with malonate, involves maintaining the correct balance of acyl-EncC substrates for efficient polyketide assembly. Here, we report the characterization of EncL as a type II thioesterase that functions to edit starter unit (mis)priming of EncC. We performed a series of in vivo mutational studies, heterologous expression experiments, in vitro reconstitution studies, and Fourier-transform mass spectrometry-monitored competitive enzyme assays that together support the proposed selective hydrolase activity of EncL toward misprimed acetyl-ACP over benzoyl-ACP to facilitate benzoyl priming of the enterocin PKS complex. While this system resembles the R1128 PKS that also utilizes an editing thioesterase (ZhuC) to purge acetate molecules from its initiation module ACP in favor of alkylacyl groups, the enterocin system is distinct in its usage of a single ACP for both priming and elongating reactions with different substrates. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Inactivation of Listeria monocytogenes in raw fruits by enterocin AS-48.
Molinos, Antonio Cobo; Abriouel, Hikmate; Ben Omar, Nabil; Lucas, Rosario; Valdivia, Eva; Gálvez, Antonio
2008-12-01
The purpose of this study was to determine the effect of enterocin AS-48 on Listeria monocytogenes CECT 4032 in fruits and fruit juice. Fruits were contaminated with a L. monocytogenes cell suspension, washed with enterocin AS-48 (25 microg/ml) or with sterile distilled water as control, and stored at different temperatures (-20, 6, 15, 22 degrees C). Washing treatments significantly inhibited or completely inactivated L. monocytogenes in strawberries, raspberries, and blackberries stored at 15 and 22 degrees C for up to 2 days and in blackberries and strawberries at 6 degrees C for up to 7 days. Washing treatments with enterocin AS-48 also reduced viable counts in sliced melon, watermelon, pear, and kiwi but did not avoid proliferation of survivors during storage at 15 and 22 degrees C. Added enterocin (25 microg/ml) completely inactivated L. monocytogenes in watermelon juice within 24 h. To enhance the antilisterial activity of treatments, enterocin AS-48 was tested in combination with other antimicrobial substances on sliced melon stored at 22 degrees C. The combinations of enterocin AS-48 and trisodium trimetaphosphate, sodium lactate, lactic acid, polyphosphoric acid, carvacrol, hydrocinnamic acid, p-hydroxybenzoic acid, n-propyl p-hydroxybenzoate, or 2-nitropropanol showed increased antilisterial activities compared with each antimicrobial tested separately. Washing treatments with enterocin AS-48 in combination with 12 mM carvacrol, as well as with 100 mM n-propyl p-hydroxybenzoate, avoided regrowth of Listeria during storage at 22 degrees C. Results from this study indicate that enterocin AS-48 alone or in combination with other preservatives could serve as an additional hurdle against L. monocytogenes in fruits and fruit juices.
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Mechanism of Nisin, Pediocin 34, and Enterocin FH99 Resistance in Listeria monocytogenes.
Kaur, Gurpreet; Singh, Tejinder Pal; Malik, Ravinder Kumar; Bhardwaj, Arun
2012-03-01
Nisin-, pediocin 34-, and enterocin FH99-resistant variants of Listeria monocytogenes ATCC 53135 were developed. In an attempt to clarify the possible mechanisms underlying bacteriocin resistance in L. monocytogenes ATCC 53135, sensitivity of the resistant strains of L. monocytogenes ATCC 53135 to nisin, pediocin 34, and enterocin FH99 in the absence and presence of different divalent cations was assessed, and the results showed that the addition of divalent cations significantly reduced the inhibitory activity of nisin, pediocin 34, and enterocin FH99 against resistant variants of L. monocytogenes ATCC 53135. The addition of EDTA, however, restored this activity suggesting that the divalent cations seem to affect the initial electrostatic interaction between the positively charged bacteriocin and the negatively charged phospholipids of the membrane. Nisin-, pediocin 34-, and enterocin-resistant variants of L. monocytogenes ATCC 53135 were more resistant to lysozyme as compared to the wild-type strain both in the presence as well as absence of nisin, pediocin 34, and enterocin FH99. Ultra structural profiles of bacteriocin-sensitive L. monocytogenes and its bacteriocin-resistant counterparts revealed that the cells of wild-type strain of L. monocytogenes were maximally in pairs or short chains, whereas, its nisin-, pediocin 34-, and enterocin FH99-resistant variants tend to form aggregates. Results indicated that without a cell wall, the acquired nisin, pediocin 34, and enterocin FH99 resistance of the variants was lost. Although the bacteriocin-resistant variants appeared to lose their acquired resistance toward nisin, pediocin 34, and enterocin FH99, the protoplasts of the resistant variants appeared to be more resistant to bacteriocins than the protoplasts of their wild-type counterparts.
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Gómez, Natacha Caballero; Abriouel, Hikmate; Grande, M A José; Pulido, Rubén Pérez; Gálvez, Antonio
2012-05-01
Enterocin AS-48 was tested on a cocktail of Listeria monocytogenes strains in planktonic and sessile states, singly or in combination with biocides benzalkonium chloride, cetrimide, hexadecylpyridinium chloride, didecyldimethylammonium bromide, triclosan, poly-(hexamethylen guanidinium) hydrochloride, chlorhexidine, hexachlorophene, and the commercial sanitizers P3 oxonia and P3 topax 66. Combinations of sub-inhibitory bacteriocin concentrations and biocide concentrations 4 to 10-fold lower than their minimum inhibitory concentrations (MIC) completely inhibited growth of the planktonic listeriae. Inactivation of Listeria in biofilms formed on polystyrene microtiter plates required concentrations of enterocin AS-48 greater than 50 μg/ml, and biocide concentrations ten to 100-fold higher. In combination with enterocin AS-48 (25 or 50 μg/ml), microbial inactivation increased remarkably for all biocides except P3 oxonia and P3 topax 66 solutions. Polystyrene microtiter plates conditioned with enterocin solutions (0.5-25 μg/ml) decreased the adherence and biofilm formation of the L. monocytogenes cell cocktail, avoiding biofilm formation for at least 24 h at a bacteriocin concentration of 25 μg/ml. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Caballero Gómez, Natacha; Abriouel, Hikmate; Grande, M José; Pérez Pulido, Rubén; Gálvez, Antonio
2013-05-15
Control of staphylococci during cleaning and disinfection is important to the food industry. Broad-spectrum bacteriocins with proved anti-staphylococcal activity, such as enterocin AS-48, could open new possibilities for disinfection in combination with biocides. In the present study, enterocin AS-48 was tested singly or in combination with biocides against a cocktail of six Staphylococcus aureus strains (including three methicillin-resistant strains) in planktonic state as well as in biofilms formed on polystyrene microtiter plates. Cells were challenged with enterocin, biocides or enterocin/biocide combinations. Inactivation of planktonic cells increased significantly (penterocin AS-48 (25mg/l) was tested in combination with benzalkonium chloride (BC), cetrimide (CT) and hexadecylpyridinium chloride (HDP), and non-significantly in combination with didecyldimethylammonium bromide (AB), triclosan (TC), hexachlorophene (CF), polyhexamethylen guanidinium chloride (PHMG), chlorhexidine (CH) or P3-oxonia (OX). In the sessile state (24h biofilms), staphylococci required higher biocide concentrations in most cases, except for OX. Inactivation of sessile staphylococci increased remarkably when biocides were applied in combination with enterocin AS-48, especially when the bacteriocin was added at 50mg/l. During storage, the concentrations of sessile as well as planktonic cells in the treated samples decreased remarkably for BC, TC and PHMG, but OX failed to inhibit proliferation of the treated biofilms as well as growth of planktonic cells. The observed inhibitory effects during storage were potentiated when the biocides were combined with 50 mg/l enterocin AS-48. Results from this study suggest that selected combinations of enterocin AS-48 and biocides offer potential use against planktonic and sessile, methicillin-sensitive and methicillin-resistant S. aureus. Copyright © 2013 Elsevier B.V. All rights reserved.
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Biotechnical paving of recombinant enterocin A as the candidate of anti-Listeria agent.
Hu, Xiaoyuan; Mao, Ruoyu; Zhang, Yong; Teng, Da; Wang, Xiumin; Xi, Di; Huang, Jianzhong; Wang, Jianhua
2014-08-28
Enterocin A is a classic IIa bacteriocin isolated firstly from Enterococcus faecium CTC492 with selective antimicrobial activity against Listeria strains. However, the application of enterocin A as an anti-Listeria agent has been limited due to its very low native yield. The present work describes high production of enterocin A through codon optimization strategy and its character study. The gene sequence of enterocin A was optimized based on preferential codon usage in Pichia pastoris to increase its expression efficiency. The highest anti-Listeria activity reached 51,200 AU/ml from 180 mg/l of total protein after 24 h of induction in a 5-L fermenter. Recombinant enterocin A (rEntA), purified by gel filtration chromatography, showed very strong activity against Listeria ivanovii ATCC 19119 with a low MIC of 20 ng/ml. In addition, the rEntA killed over 99% of tested L. ivanovii ATCC19119 within 4 h when exposed to 4 × MIC (80 ng/ml). Moreover, it showed high stability under a wide pH range (2-10) and maintained full activity after 1 h of treatment at 80°C within a pH range of 2-8. Its antimicrobial activity was enhanced at 25 and 50 mM NaCl, while 100-400 mM NaCl had little effect on the bactericidal ability of rEntA. The EntA was successfully expressed in P. pastoris, and this feasible system could pave the pre-industrial technological path of rEntA as a competent candidate as an anti-Listeria agent. Furthermore, it showed high stability under wide ranges of conditions, which could be potential as the new candidate of anti-Listeria agent.
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Characterization of an anti-listerial enterocin from wheat silage based Enterococcus faecium.
Bal, Emel Banu Buyukunal; Isevi, Taner; Bal, Mehmet Ali
2012-10-01
Two Enterococcus faecium and one E. faecalis strains isolated and identified from wheat silage were characterized based on plasmid content, hemolytic activity, antibiotic resistance patterns, bacteriocin production potential, and presence of enterocin structural genes (entA, entB, entP, entL50B). Among the isolates, only the E. faecium U7 strain exhibited bacteriocin activity against Listeria monocytogenes ATCC 7644, and vancomycin resistant Enterococcus spp. (VRE). A combination of three structural genes (entA, entB, and entP) was detected in E. faecium U7. A relationship between the presence of enterocin structural genes, and bacteriocin activity was detected in E. faecium U7; therefore partially purified enterocin (PPE) was further investigated from the isolate. Several bands of different molecular weights were expressed from PPE extracts following tricine SDS-PAGE analysis. However, the only band showing bacteriocin activity was in an approximate 4-kDa region. PPE treatment with proteinase K, lysozyme, and α -amylase caused complete loss of bacteriocin activity. PPE heat treatment at various temperatures resulted in a notable reduction in bacteriocin expression. Enterocin U7 was relatively heat stable, and presumably exhibits a glucoprotein nature with distinct inhibitory properties. Specific bacterial inhibitory activity of enterocin U7, and the producer strain absence of β -hemolysis and vancomycin susceptibility features deserves further investigation to evaluate its potential application in silage inoculation and food preservation. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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Antibacterial protection by enterocin AS-48 in sport and energy drinks with less acidic pH values.
Viedma, Pilar Martinez; Abriouel, Hikmate; Ben Omar, Nabil; López, Rosario Lucas; Valdivia, Eva; Gálvez, Antonio
2009-04-01
The low pH and acid content found in sports and energy drinks are a matter of concern in dental health. Raising the pH may solve this problem, but at the same time increase the risks of spoilage or presence of pathogenic bacteria. In the present study, commercial energy drinks were adjusted to pH 5.0 and challenged with Listeria monocytogenes (drinks A to F), Staphylococcus aureus, Bacillus cereus, and Bacillus licheniformis (drink A) during storage at 37 degrees C. L. monocytogenes was able to grow in drink A and survived in drinks D and F for at least 2 days. Addition of enterocin AS-48 (1 microg/ml final concentration) rapidly inactivated L. monocytogenes in all drinks tested. S. aureus and B. cereus also survived quite well in drink A, and were completely inactivated by 12.5 microg/ml enterocin AS-48 after 2 days of storage or by 25 microg/ml bacteriocin after 1 day. B. licheniformis was able to multiply in drink A, but it was completely inactivated by 5 microg/ml enterocin AS-48 after 2 days of storage or by 12.5 microg/ml bacteriocin after 1 day. Results from the present study suggest that enterocin AS-48 could be used as a natural preservative against these target bacteria in less acidic sport and energy drinks.
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Ankaiah, Dasari; Palanichamy, Esakkiraj; Antonyraj, Christian Bharathi; Ayyanna, Repally; Perumal, Venkatesh; Ahamed, Syed Ibrahim Basheer; Arul, Venkatesan
2018-05-02
In this present study, a gene (ent-B) encoding the bacteriocin enterocin-B was cloned, overexpressed and purified from Enterococcus faecium por1. The molecular weight of the bacteriocin enterocin-B was observed around 7.2 kDa and exhibited antimicrobial activity against several human pathogenic bacteria. The antimicrobial activity of cloned enterocin-B was increased effectively by combining with another bacteriocin enterocin-A from the same microorganism. Protein-protein docking and molecular dynamics simulation studies revealed that the bacteriocin enterocin-B is interacting with enterocin-A and formation of a heterodimer (enterocin A + B). The heterodimer of bacteriocin enterocin-A + B exhibited potential anti-bacterial, anti-biofilm activity against Staphylococcus aureus, Acinetobacter baumannii, Listeria monocytogenes and Escherichia coli. The bacteriocin enterocin-B, A and heterodimer of bacteriocin enterocin A + B showed no haemolysis on human RBC cells. This is the first report that the cell growth inhibitory activity of the bacteriocin enterocin B against HeLa, HT-29 and AGS human cancer cells and this cell growth inhibitory activity was significantly increased when cancer cells treated with the heterodimer of bacteriocins enterocin-A + B. The cell growth inhibitory activity of the bacteriocin enterocin-B and the heterodimer of bacteriocin enterocin-A + B were not observed in non-cancerous INT-407 cells (intestinal epithelial cells). Copyright © 2018. Published by Elsevier B.V.
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Kumar, Manoj; Srivastava, Sheela
2010-10-01
Enterocin LR/6, a purified bacteriocin, exhibited broad inhibitory spectrum both against related as well as some food-borne pathogens such as Listeria monocytogenes, Yersinia enterocolitica, Aeromonas sp., Shigella sp., and Bacillus licheniformis. In this investigation, we have focused on L. monocytogenes as the target organism, as it is not only an important pathogen but can also survive over a wide range of environmental conditions such as refrigeration temperature, low pH, and high-salt concentration. This allows the pathogen to overcome many food preservation and safety barriers and poses a potential risk to human health. The enterocin LR/6 showed a bactericidal action against L. monocytogenes and completely inhibited the growth on agar plates, supplemented with 200 AU/ml of enterocin LR/6. The effectiveness of enterocin LR/6 in completely killing a population of acid-adapted (pH 5.2, 2 h) L. monocytogenes exposed to different temperatures (4-37 degrees C), pH (2.5-8.0), and osmotic (up to 30% NaCl) stress is reported here. This paper focuses on the key issue of killing of the acid-adapted L. monocytogenes cells under adverse environmental conditions.
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Kaur, Gurpreet; Singh, Tejinder Pal; Malik, Ravinder Kumar; Bhardwaj, Arun; De, Sachinandan
2014-02-01
The bacteriocin susceptibility of Listeria monocytogenes MTCC 657, Enterococcus faecium DSMZ 20477, E. faecium VRE, and E. faecalis ATCC 29212 and their corresponding bacteriocin resistant variants was assessed. The single and combined effect of nisin and pediocin 34 and enterocin FH99 bacteriocins produced by Pediococcus pentosaceus 34, and E. faecium FH99, respectively, was determined. Pediocin34 proved to be more effective in inhibiting L. monocytogenes MTCC 657. A greater antibacterial effect was observed against E. faecium DSMZ 20477 and E. faecium (VRE) when the a combination of nisin, pediocin 34 and enterocin FH99 were used whereas in case of L. monocytogenes MTCC 657 a combination of pediocin 34 and enterocin FH99 was more effective in reducing the survival of pathogen. Bacteriocin cross-resistance and the antibiotic susceptibility of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class and also the acquired resistance to bacteriocins can modify the antibiotic susceptibility/resistance profile of the bacterial species used in the study. According to the hydrophobicity nisin resistant variant of L. monocytogenes was more hydrophobic (p enterocin FH99 resistant variants were less hydrophobic than the wild type strain. Nisin, pediocin 34 and enterocin FH99 resistant variants of E. faecium DSMZ 20477 and E. faecium VRE were less hydrophobic than their wild type counterparts. Nisin resistant E. faecalis ATCC 29212 was less hydrophobic than its wild type counterpart.
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Enterocin CRL35 inhibits Listeria monocytogenes in a murine model.
Salvucci, Emiliano; Saavedra, Lucila; Hebert, Elvira Maria; Haro, Cecilia; Sesma, Fernando
2012-01-01
Listeria monocytogenes is a foodborne pathogen causative of opportunistic infections. Listeriosis is associated with severe infections in pregnant women causing abortion or neonatal listeriosis. An alternative to antibiotics are safe novel bacteriocins peptides such as enterocin CRL35 with strong antilisterial activity produced by Enterococcus mundtii CRL35. In the present paper, our goal is to study the effectiveness of this peptide and the producer strain in a murine model of pregnancy-associated listeriosis. A single dose of 5×10(9) colony-forming unit of L. monocytogenes FBUNT (Faculty of Biochemistry-University of Tucumán) resulted in translocation of pathogen to liver and spleen of BALB/c pregnant mice. The maximum level of Listeria was observed on day 3 postinfection. Interestingly, the intragastric administration of enterocin CRL35 significantly reduced the translocation of the pathogen to vital organs. On the other hand, the preadministration of E. mundtii CRL35 slightly inhibited this translocation. Listeria infection caused a significant increase in polymorphonuclear leukocytes at day 3 postinfection compared to the noninfected group. This value was reduced after the administration of enterocin CRL35. No significant changes were observed in either white blood cells or lymphocytes counts. Based on the data presented in the present work enterocin CRL35 would be a promising alternative for the prevention of Listeria infections.
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Ghrairi, Taoufik; Hani, Khaled
2015-04-01
The combined effects of enterocin A with Thymus vulgaris essential oils (EOs) against Listeria monocytogenes and Escherichia coli O157:H7 were investigated in vitro by enumeration of surviving populations of testing pathogens and minimal inhibitory concentration (MIC) determination. Enterocin A was purified to homogeneity by RP-HPLC from the culture fluid of Enterococcus strain and thyme EOs were extracted from local Thymus vulgaris plants. The major constituent of thyme EOs oils determined by GC-MS was thymol (78.4 %). Combination of enterocin A with thyme EOs showed an enhanced bactericidal effect against Listeria monocytogenes. Checkerboard assay and isobologram construction displayed a synergistic interaction between these compounds against Listeria (FIC index enterocin A has fallen fivefold (from 4.57 to 0.9 μg/ml), while the MIC of thyme EOs decreased threefold (from 3.6 to 1.2 μg/ml). Treatments with enterocin A alone did not affect the growth of the enteric pathogen E. coli O157:H7. However, the addition of thyme EOs and enterocin A yielded a synergistic antimicrobial effect against E. coli (MIC thyme EOs decrease from 2.2 to 0.71 μg/ml). This is the first report on the combined effect of enterocin A and thyme EOs against food pathogen bacteria. This combination could be useful in food bio-preservation.
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Enterocin F4-9, a Novel O-Linked Glycosylated Bacteriocin.
Maky, Mohamed Abdelfattah; Ishibashi, Naoki; Zendo, Takeshi; Perez, Rodney Honrada; Doud, Jehan Ragab; Karmi, Mohamed; Sonomoto, Kenji
2015-07-01
Enterococcus faecalis F4-9 isolated from Egyptian salted-fermented fish produces a novel bacteriocin, termed enterocin F4-9. Enterocin F4-9 was purified from the culture supernatant by three steps, and its molecular mass was determined to be 5,516.6 Da by mass spectrometry. Amino acid and DNA sequencing showed that the propeptide consists of 67 amino acid residues, with a leader peptide containing a double glycine cleavage site to produce a 47-amino-acid mature peptide. Enterocin F4-9 is modified by two molecules of N-acetylglucosamine β-O-linked to Ser37 and Thr46. The O-linked N-acetylglucosamine moieties are essential for the antimicrobial activity of enterocin F4-9. Further analysis of the enterocin F4-9 gene cluster identified enfC, which has high sequence similarity to a glycosyltransferase. The antimicrobial activity of enterocin F4-9 covered a limited range of bacteria, including, interestingly, a Gram-negative strain, Escherichia coli JM109. Enterocin F4-9 is sensitive to protease, active at a wide pH range, and moderately resistant to heat. Copyright © 2015, American Society for Microbiology. All Rights Reserved.
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Martínez, José M.; Kok, Jan; Sanders, Jan W.; Hernández, Pablo E.
2000-01-01
Antibodies against enterocin A were obtained by immunization of rabbits with synthetic peptides PH4 and PH5 designed, respectively, on the N- and C-terminal amino acid sequences of enterocin A and conjugated to the carrier protein KLH. Anti-PH4-KLH antibodies not only recognized enterocin A but also pediocin PA-1, enterocin P, and sakacin A, three bacteriocins which share the N-terminal class IIa consensus motif (YGNGVXC) that is contained in the sequence of the peptide PH4. In contrast, anti-PH5-KLH antibodies only reacted with enterocin A because the amino acid sequences of the C-terminal parts of class IIa bacteriocins are highly variable. Enterocin A and/or pediocin PA-1 structural and immunity genes were introduced in Lactococcus lactis IL1403 to achieve (co)production of the bacteriocins. The level of production of the two bacteriocins was significantly lower than that obtained by the wild-type producers, a fact that suggests a low efficiency of transport and/or maturation of these bacteriocins by the chromosomally encoded bacteriocin translocation machinery of IL1403. Despite the low production levels, both bacteriocins could be specifically detected and quantified with the anti-PH5-KLH (anti-enterocin A) antibodies isolated in this study and the anti-PH2-KLH (anti-pediocin PA-1) antibodies previously generated (J. M. Martínez, M. I. Martínez, A. M. Suárez, C. Herranz, P. Casaus, L. M. Cintas, J. M. Rodríguez, and P. E. Hernández, Appl. Environ. Microbiol. 64:4536–4545, 1998). In this work, the availability of antibodies for the specific detection and quantification of enterocin A and pediocin PA-1 was crucial to demonstrate coproduction of both bacteriocins by L. lactis IL1403(pJM04), because indicator strains that are selectively inhibited by each bacteriocin are not available. PMID:10919819
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Enterocin P Causes Potassium Ion Efflux from Enterococcus faecium T136 Cells
Herranz, Carmen; Cintas, Luis M.; Hernández, Pablo E.; Moll, Gert N.; Driessen, Arnold J. M.
2001-01-01
Enterocin P is a bacteriocin produced by Enterococcus faecium P13. We studied the mechanism of its bactericidal action using enterocin-P-sensitive E. faecium T136 cells. The bacteriocin is incapable of dissipating the transmembrane pH gradient. On the other hand, depending on the buffer used, enterocin P dissipates the transmembrane potential. Enterocin P efficiently elicits efflux of potassium ions, but not of intracellularly accumulated anions like phosphate and glutamate. Taken together, these data demonstrate that enterocin P forms specific, potassium ion-conducting pores in the cytoplasmic membrane of target cells. PMID:11181377
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Staphylococci Related to Farm Ostriches and Their Sensitivity to Enterocins.
Kandričáková, Anna; Lauková, Andrea; Ščerbová, Jana
2016-03-01
In Slovakia, ostriches are reared mainly for their meat. There is still limited information related to microflora of ostriches, including staphylococci. Knowing the composition of microflora is very important for the recognition of potential pathogenic agents. Recently, a frequent problem in animals is the occurrence of bacteria resistant to antibiotics. The aim of this study was to detect staphylococcal species in feces of farm ostriches and to test their sensitivity to antibiotics and enterocins. Altogether 140 ostriches from three age groups were sampled (n = 18, faecal mixture samples from each group) on a farm in Slovakia or on Slovak farm. From 54 fecal samples, the staphylococcal count reached an average 4. 3 ± 0. 63 (log10) CFU/g. Twenty-four lactic acid producing strains were taxonomically classified to eight species of the genus Staphylococcus: Staphylococcus equorum, S. xylosus, S. epidermidis, S. haemolyticus, S. cohnii, S. succinus, S. warneri, and S. hominis. Strains were evaluated by secure probable species identification/probable species identification (score value up to 2.299) confirmed also by phenotypization. Most strains were sensitive to antibiotics. Four strains (S. haemolyticus SHae 111, S. haemolyticus SHAe 371, S. xylosus SX 2133, and S. warneri SW 292) were resistant to methicillin but sensitive to six or five of the seven enterocins tested (inhibitory activity 200-12,800 AU/mL). S. warneri SW 292 was sensitive to all enterocins (activity up to 12,800 AU/mL).
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Line, J E; Svetoch, E A; Eruslanov, B V; Perelygin, V V; Mitsevich, E V; Mitsevich, I P; Levchuk, V P; Svetoch, O E; Seal, B S; Siragusa, G R; Stern, N J
2008-03-01
Strain NRRL B-30745, isolated from chicken ceca and identified as Enterococcus durans, Enterococcus faecium, or Enterococcus hirae, was initially identified as antagonistic to Campylobacter jejuni. The isolate produced a 5,362-Da bacteriocin (enterocin) that inhibits the growth of Salmonella enterica serovar Enteritidis, S. enterica serovar Choleraesuis, S. enterica serovar Typhimurium, S. enterica serovar Gallinarum, Escherichia coli O157:H7, Yersinia enterocolitica, Citrobacter freundii, Klebsiella pneumoniae, Shigella dysenteriae, Pseudomonas aeruginosa, Proteus mirabilis, Morganella morganii, Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Campylobacter jejuni, and 20 other Campylobacter species isolates. The enterocin, E-760, was isolated and purified by cation-exchange and hydrophobic-interaction chromatographies. The proteinaceous nature of purified enterocin E-760 was demonstrated upon treatment with various proteolytic enzymes. Specifically, the antimicrobial peptide was found to be sensitive to beta-chymotrypsin, proteinase K, and papain, while it was resistant to lysozyme and lipase. The enterocin demonstrated thermostability by retaining activity after 5 min at 100 degrees C and was stable at pH values between 5.0 and 8.7. However, activity was lost below pH 3.0 and above pH 9.5. Administration of enterocin E-760-treated feed significantly (P Enterocin E-760 also significantly (P < 0.05) reduced the colonization of naturally acquired Campylobacter species in market age broiler chickens when administered in treated feed 4 days prior to analysis.
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Enterocin P Causes Potassium Ion Efflux from Enterococcus faecium T136 Cells
Herranz, Carmen; Cintas, Luis M.; Hernández, Pablo E.; Moll, Gert N.; Driessen, Arnold J. M.
2001-01-01
Enterocin P is a bacteriocin produced by Enterococcus faecium P13. We studied the mechanism of its bactericidal action using enterocin-P-sensitive E. faecium T136 cells. The bacteriocin is incapable of dissipating the transmembrane pH gradient. On the other hand, depending on the buffer used, enterocin P dissipates the transmembrane potential. Enterocin P efficiently elicits efflux of potassium ions, but not of intracellularly accumulated anions like phosphate and glutamate. Taken together, t...
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Directory of Open Access Journals (Sweden)
Wenli Liu
2017-01-01
Full Text Available The macro- and micronutrients in traditional medium, such as MRS, used for cultivating lactic acid bacteria, especially for bacteriocin production, have not been defined, preventing the quantitative monitoring of metabolic flux during bacteriocin biosynthesis. To enhance Enterocin Y31 production and simplify steps of separation and purification, we developed a simplified chemically defined medium (SDM for the growth of Enterococcus faecium Y31 and production of its bacteriocin, Enterocin Y31. We found that the bacterial growth was unrelated to Enterocin Y31 production in MRS; therefore, both the growth rate and the Enterocin Y31 production were set as the index for investigation. Single omission experiments revealed that 5 g/L NaCl, five vitamins, two nucleic acid bases, MgSO4·7H2O, MnSO4·4H2O, KH2PO4, K2HPO4, CH3COONa, fourteen amino acids, and glucose were essential for the strain’s growth and Enterocin Y31 production. Thus, a novel simplified and defined medium (SDM was formulated with 30 components in total. Consequently, Enterocin Y31 production yield was higher in SDM as compared to either MRS or CDM. SDM improved the Enterocin Y31 production and simplified the steps of purification (only two steps, which has broad potential applications.
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Directory of Open Access Journals (Sweden)
Scarlet S Shell
2015-11-01
Full Text Available RNA-seq technologies have provided significant insight into the transcription networks of mycobacteria. However, such studies provide no definitive information on the translational landscape. Here, we use a combination of high-throughput transcriptome and proteome-profiling approaches to more rigorously understand protein expression in two mycobacterial species. RNA-seq and ribosome profiling in Mycobacterium smegmatis, and transcription start site (TSS mapping and N-terminal peptide mass spectrometry in Mycobacterium tuberculosis, provide complementary, empirical datasets to examine the congruence of transcription and translation in the Mycobacterium genus. We find that nearly one-quarter of mycobacterial transcripts are leaderless, lacking a 5' untranslated region (UTR and Shine-Dalgarno ribosome-binding site. Our data indicate that leaderless translation is a major feature of mycobacterial genomes and is comparably robust to leadered initiation. Using translational reporters to systematically probe the cis-sequence requirements of leaderless translation initiation in mycobacteria, we find that an ATG or GTG at the mRNA 5' end is both necessary and sufficient. This criterion, together with our ribosome occupancy data, suggests that mycobacteria encode hundreds of small, unannotated proteins at the 5' ends of transcripts. The conservation of small proteins in both mycobacterial species tested suggests that some play important roles in mycobacterial physiology. Our translational-reporter system further indicates that mycobacterial leadered translation initiation requires a Shine Dalgarno site in the 5' UTR and that ATG, GTG, TTG, and ATT codons can robustly initiate translation. Our combined approaches provide the first comprehensive view of mycobacterial gene structures and their non-canonical mechanisms of protein expression.
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Yildirim, Zeliha; Bilgin, Harun; Isleroglu, Hilal; Tokatli, Kader; Sahingil, Didem; Yildirim, Metin
2014-05-01
Bacteriogenic Enterococcus faecium HZ was identified by using biochemical (Strep-API 20, API-50 CHL, fatty acid profile) and 16S rRNA analysis (99·99 %). Ent. faecium HZ was sensitive to clinically important antibiotics such as vancomycin, and did not have gelatinase and haemolysis activities. Enterocin HZ, a bacteriocin from Ent. faecium HZ, was sensitive to papain and tyripsin, but resistant to pepsin, lipase, catalase, α-amylase, organic solvents, detergents, ß-mercaptoethanol, and heat treatment (90 °C/30 min). It was biologically active at pH 2·0-9·0 and synthesised at the highest level in MRS or M17 broth at 32 or 37 °C with an inoculum amount of 0·1-0·5 % and an initial pH of 6·0-7·0. Enterocin HZ production reached maximum level at middle and late logarithmic phase and its molecular weight was ∼4·5 kDa. It was active against some Gram-positive foodborne bacteria. Ent. faecium HZ or its bacteriocin enterocin HZ is a good candidate to be studied as a food biopreservative since enterocin HZ showed strong bactericidal activity against Listeria monocytogenes in UHT milk and also Ent. faecium HZ grew very well in milk and produced enterocin HZ at maximum level.
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Enterocin F4-9, a Novel O-Linked Glycosylated Bacteriocin
Maky, Mohamed Abdelfattah; Ishibashi, Naoki; Zendo, Takeshi; Perez, Rodney Honrada; Doud, Jehan Ragab; Karmi, Mohamed; Sonomoto, Kenji
2015-01-01
Enterococcus faecalis F4-9 isolated from Egyptian salted-fermented fish produces a novel bacteriocin, termed enterocin F4-9. Enterocin F4-9 was purified from the culture supernatant by three steps, and its molecular mass was determined to be 5,516.6 Da by mass spectrometry. Amino acid and DNA sequencing showed that the propeptide consists of 67 amino acid residues, with a leader peptide containing a double glycine cleavage site to produce a 47-amino-acid mature peptide. Enterocin F4-9 is modi...
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Belguesmia, Y; Choiset, Y; Prévost, H; Dalgalarrondo, M; Chobert, J-M; Drider, D
2010-01-01
The aim of this research was to purify and characterize the mode of action of enterocin S37, a bacteriocin produced by Enterococcus faecalis S37, a strain recently isolated from the chicken feces. Enterocin S37 has a molecular weight comprised between 4 and 5 kDa. It remained active after 1 h at 80(o)C and at pH values ranging from 4.0 to 9.0. Furthermore, cell-free supernatant of Enterococcus faecalis S37 and purified enterocin S37 were active against Gram-positive bacteria including Listeria monocytogenes EGDe, L. innocua F, Enterococcus faecalis JH2-2, and Lactobacillus brevis F145. The purification of enterocin S37 was performed by ammonium sulfate precipitation followed up by hydrophobic-interaction chromatography procedures. Treatment of enterocin S37 with proteinase K, alpha-chymotrypsin, and papain confirmed its proteinaceous nature, while its treatment with lysozyme and lipase resulted in no alteration of activity. Enterocin S37 is hydrophobic, anti-Listeria and likely acting by depletion of intracellular K(+) ions upon action on K(ATP) channels. This study contributed to gain more insights into the mode of action of enterocins.
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Directory of Open Access Journals (Sweden)
Y. Belguesmia
2010-01-01
Full Text Available The aim of this research was to purify and characterize the mode of action of enterocin S37, a bacteriocin produced by Enterococcus faecalis S37, a strain recently isolated from the chicken feces. Enterocin S37 has a molecular weight comprised between 4 and 5 kDa. It remained active after 1 h at 80oC and at pH values ranging from 4.0 to 9.0. Furthermore, cell-free supernatant of Enterococcus faecalis S37 and purified enterocin S37 were active against Gram-positive bacteria including Listeria monocytogenes EGDe, L. innocua F, Enterococcus faecalis JH2-2, and Lactobacillus brevis F145. The purification of enterocin S37 was performed by ammonium sulfate precipitation followed up by hydrophobic-interaction chromatography procedures. Treatment of enterocin S37 with proteinase K, -chymotrypsin, and papain confirmed its proteinaceous nature, while its treatment with lysozyme and lipase resulted in no alteration of activity. Enterocin S37 is hydrophobic, anti-Listeria and likely acting by depletion of intracellular K+ ions upon action on KATP channels. This study contributed to gain more insights into the mode of action of enterocins.
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Burgos, María José Grande; Aguayo, M Carmen López; Pulido, Rubén Pérez; Gálvez, Antonio; López, Rosario Lucas
2015-09-01
The presence of toxicogenic Staphylococcus aureus in foods and the dissemination of methicillin-resistant S. aureus (MRSA) in the food chain are matters of concern. In the present study, the circular bacteriocin enterocin AS-48, applied singly or in combination with phenolic compounds (carvacrol, eugenol, geraniol, and citral) or with 2-nitro-1-propanol (2NPOH), was investigated in the control of a cocktail made from 1 methicillin-sensitive and 1 MRSA strains inoculated on commercial oat and soya drinks. Enterocin AS-48 exhibited low bactericidal activity against staphylococci in the drinks investigated when applied singly. The combinations of sub-inhibitory concentrations of enterocin AS-48 (25 μg/mL) and phenolic compounds or 2NPOH caused complete inactivation of staphylococci in the drinks within 24 h of incubation at 22 °C. When tested in oat and soya drinks stored for 7 d at 10 °C, enterocin AS-48 (25 μg/mL) in combination with 2NPOH (5.5 mM) reduced viable counts rapidly in the case of oat drink (4.2 log cycles after 12 h) or slowly in soya drink (3.8 log cycles after 3 d). The same combined treatment applied on drinks stored at 22 °C achieved a fast inactivation of staphylococci within 12 to 24 h in both drinks, and no viable staphylococci were detected for up to 7 d of storage. Results from the study highlight the potential of enterocin AS-48 in combination with 2NPOH for inactivation of staphylococci. © 2015 Institute of Food Technologists®
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Caballero Gómez, Natacha; Abriouel, Hikmate; Ennahar, Said; Gálvez, Antonio
2013-10-15
Enterocin AS-48 is a cyclic peptide of great interest for application in food preservation and sanitation. In the present study, the proteome response of Listeria monocytogenes to purified enterocin AS-48 was studied under two different conditions: planktonic cells and sessile cells grown on polystyrene plates. Ten different proteins were differentially expressed in planktonic L. monocytogenes cells treated with 0.1 μg/ml enterocin AS-48 compared to the untreated controls. Overexpressed proteins were related to stress response (DnaK) or carbohydrate transport and metabolism, while underexpressed and unexpressed proteins were related to metabolism (such as glyceraldehyde-3-phosphate dehydrogenase, pyruvate oxidase, glutamate dehydrogenase or glutamate decarboxylase) or stress (GroEL). In the sessile state, L. monocytogenes cells tolerated up to 10 μg/ml bacteriocin, and the treated biofilm cells overexpressed a set of 11 proteins, some of which could be related to stress response (DnaK, GroEL), protein synthesis and carbohydrate metabolism, while glyceraldehyde-3-phosphate dehydrogenase was the only unexpressed protein. Some of the overexpressed proteins (such as elongation factor Tu and GroEL) could also be implicated in cell adhesion. These results suggest different cell responses of L. monocytogenes to enterocin AS-48 in the planktonic and in the sessile state, including stress response and cell metabolism proteins. While in the planktonic state the bacterium may tend to compensate for the cytoplasmic cell permeability changes induced by AS-48 by reinforcing carbohydrate transport and metabolism, sessile cells seem to respond by shifting carbohydrate metabolism and reinforcing protein synthesis. Stress response proteins also seem to be important in the response to AS-48, but the stress response seems to be different in planktonic and in sessile cells. © 2013.
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Enterocin M and its Beneficial Effects in Horses-a Pilot Experiment.
Lauková, Andrea; Styková, Eva; Kubašová, Ivana; Gancarčíková, Soňa; Plachá, Iveta; Mudroňová, Dagmar; Kandričáková, Anna; Miltko, Renata; Belzecki, Grzegorz; Valocký, Igor; Strompfová, Viola
2018-02-07
Probiotic bacteria or their antimicrobial proteinaceous substances called bacteriocins (enterocins) hold promising prophylactic potential for animal breeding. This study present the results achieved after application of Enterocin M in horses. Enterocin M has never been applied to horses before. Clinically healthy horses (10) were involved in this pilot experiment. They were placed in the stables of the University of Veterinary Medicine and Pharmacy, Košice, Slovakia, with the approval of the University Ethics Committee. The animals were fed twice a day with hay and oats, or alternatively grazed with access to water ad libitum. The experiment lasted 6 weeks. Sampling was performed at the start of the experiment, at day 0-1, at day 21 (3 weeks of Enterocin M application), and at day 42 (3 weeks of cessation). Feces were sampled directly from the rectum and blood from the vena jugularis; the samples were immediately treated and/or stored for analyses. Each horse itself represented a control animal (compared to its status at the start of the experiment, day 0-1). After initial sampling, the horses were administered 100 μl of Ent M (precipitate, 12,800 AU/ml) in a small feed bolus to ensure it was consumed; Ent M was applied for 3 weeks (21 days). Fecal samples were treated using the standard microbial dilution method; phagocytic activity was assessed with standard and flow cytometry; biochemistry and metabolic profiles were tested using commercial kits and standard methods. Administration of Ent M led to mathematical reduction of coliforms, campylobacters ( ab P < 0.05), and significant reduction of Clostridium spp. ( ab P < 0.001, bc P < 0.001); increase of PA values was noted (P < 0.05, P < 0.0001); no negative influence on hydrolytic enzyme profile or biochemical blood parameters was noted.
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Characterization and Application of Enterocin RM6, a Bacteriocin from Enterococcus faecalis
Huang, En; Zhang, Liwen; Chung, Yoon-Kyung; Zheng, Zuoxing; Yousef, Ahmed E.
2013-01-01
Use of bacteriocins in food preservation has received great attention in recent years. The goal of this study is to characterize enterocin RM6 from Enterococcus faecalis OSY-RM6 and investigate its efficacy against Listeria monocytogenes in cottage cheese. Enterocin RM6 was purified from E. faecalis culture supernatant using ion exchange column, multiple C18-silica cartridges, followed by reverse-phase high-performance liquid chromatography. The molecular weight of enterocin RM6 is 7145.0823 ...
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López, Rosario Lucas; García, Ma Teresa; Abriouel, Hikmate; Ben Omar, Nabil; Grande, Ma José; Martínez-Cañamero, Magdalena; Gálvez, Antonio
2007-12-01
The influence of substrate composition on the production of enterocin EJ97 and the conditions for semi-preparative bacteriocin recovery have been studied. Final bacteriocin concentrations of 12.5 or 15.6 mg/l were obtained in the commercial media brain heart infusion broth (BHI) and tryptic soya broth, respectively. The bacteriocin was also produced in the complex medium CM (8.75 mg/l), in which the vitamin supplement was essential for production. Some combinations of meat peptone and yeast extract plus either soy peptone or BHI also supported bacteriocin production, at concentrations of 6.25-7.5 mg/l. In cow milk (whole, half-skimmed, and skimmed), the final bacteriocin concentrations obtained ranged from 7.5 to 11.25 mg/l. Highest bacteriocin activity was obtained by using pasteurised milk whey as growth substrate (up to 25 mg/l), suggesting that this bacteriocin can be obtained on a large scale by using this cheap food-grade industrial by-product. Highest bacteriocin titres were always obtained after 8 h of incubation at 37 degrees C. Semi-preparative concentration and purification of enterocin EJ97 produced in a complex medium was achieved by bulk cation exchange chromatography without previous cell separation, followed by reversed-phase chromatography. This two-step procedure allowed preparation of milligram quantities of purified bacteriocin, which is an improvement compared to purification procedures established for most other bacteriocins (35). The availability of purified enterocin EJ97 will facilitate other studies such as the elucidation of its molecular structure and its interaction with target bacteria.
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Hassan, Syed Shamsul; Shah, Sayed Asmat Ali; Pan, Chengqian; Fu, Leilei; Cao, Xun; Shi, Yutong; Wu, Xiaodan; Wang, Kuiwu; Wu, Bin
2017-01-01
Elicitation by chemical means including heavy metals is one of a new technique for drug discoveries. In this research, the effect of heavy metals on marine actinobacteria Streptomyces sp. H-1003 for the production of enterocin, with a strong broad spectrum activity, along optimized fermented medium was firstly investigated. The optimum metal stress conditions consisted of culturing marine actinobacteria strain H-1003 with addition of cobalt ions at 2mM in optimized Gause's medium having starch at 20mg/L for 10 days at 180 revolution/min. Under these conditions, enterocin production was enhanced with a value of 5.33mg/L, which was totally absent at the normal culture of strain H-1003 and much higher than other tested metal-stress conditions. This work triumphantly announced a prodigious effect of heavy metals on marine actinobacteria with fringe benefits as a key tool of enterocin production.
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Williams, D Ross; Chanos, Panagiotis
2012-12-01
Listeriosis is a deadly food-borne disease, and its incidence may be limited through the biotechnological exploitation of a number of anti-listerial biocontrol agents. The most widely used of these agents are bacteriocins and the Class II enterocins are characterized by their activity against Listeria. Enterocins are primarily produced by enterococci, particularly Enterococcus faecium and many strains have been described, often encoding multiple bacteriocins. The use of these strains in food will require that they are free of virulence functions and that they exhibit a high level expression of anti-listerial enterocins in fermentation conditions. Multiplex relative RT (reverse transcription)-PCR is a technique that is useful in the discovery of advantageous expression characteristics among enterocin-producing strains. It allows the levels of individual enterocin gene expression to be monitored and determination of how expression is altered under different growth conditions.
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Heterologous expression of enterocin AS-48 in several strains of lactic acid bacteria.
Fernández, M; Martínez-Bueno, M; Martín, M C; Valdivia, E; Maqueda, M
2007-05-01
Enterococcus faecalis produces a cationic and circular enterocin, AS-48, of 7149 Da, the genetic determinants of which are located within the pMB2 plasmid. We have compared enterocin AS-48 production by different enterococci species with that of other 'safe' lactic acid bacteris (LAB) (GRAS status) and looked into the subsequent application of this enterocin in food production. In an effort to exploit this system for the heterologous expression of enterocin AS-48, a number of vectors containing the as-48 cluster were constructed and used to transform several LAB strains (genera Enterococcus, Lactococcus and Lactobacillus) Heterologous production of enterocin AS-48 failed when bacteria other than those belonging to the genus Enterococcus were used as hosts, although expression of a partial level of resistance against AS-48 were always detected, ruling out the possibility of a lack of recognition of the enterococcal promoters. Our results reveal the special capacity of species from the genus Enterococcus to produce AS-48, an enterocin that requires a post-transcriptional modification to generate a circular peptide with a wide range of inhibitory activity against pathogenic and spoilage bacteria. Preliminary experiments in foodstuffs using nonvirulent enterococci with interesting functional properties reveal the possibility of a biotechnological application of these transformants.
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Enterocin TW21, a novel bacteriocin from dochi-isolated Enterococcus faecium D081821.
Chang, S-Y; Chen, Y-S; Pan, S-F; Lee, Y-S; Chang, C-H; Chang, C-H; Yu, B; Wu, H-C
2013-09-01
Purification and characterization of a novel bacteriocin produced by strain Enterococcus faecium D081821. Enterococcus faecium D081821, isolated from the traditional Taiwanese fermented food dochi (fermented black beans), was previously found to produce a bacteriocin against Listeria monocytogenes and some Gram-positive bacteria. This bacteriocin, termed enterocin TW21, was purified from culture supernatant by ammonium sulfate precipitation, Sep-Pak C18 cartridge, ion-exchange and gel filtration chromatography. Mass spectrometry analysis showed the mass of the peptide to be approximately 5300·6 Da. The N-terminal amino acid sequencing yielded a partial sequence NH2 -ATYYGNGVYxNTQK by Edman degradation, and it contains the consensus class IIa bacteriocin motif YGNGV in the N-terminal region. The open reading frame (ORF) encoding the bacteriocin was identified from the draft genome sequence of Enterococcus faecium D081821, and sequence analysis of this peptide indicated that enterocin TW21 is a novel bacteriocin. Enterococcus faecium D081821 produced a bacteriocin named enterocin TW21, the molecular weight and amino acid sequence both revealed it to be a novel bacteriocin. A new member of class IIa bacteriocin was identified. This bacteriocin shows great inhibitory ability against L. monocytogenes and could be applied as a natural food preservative. © 2013 The Society for Applied Microbiology.
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Growing insights into the safety of bacteriocins: the case of enterocin S37.
Belguesmia, Yanath; Madi, Amar; Sperandio, Daniel; Merieau, Annabelle; Feuilloley, Marc; Prévost, Hervé; Drider, Djamel; Connil, Nathalie
2011-01-01
Very few studies have been reported on the cytotoxicity and impact of bacteriocins, and especially enterocins, upon eukaryotic cells. In order to gain more information on the safety of bacteriocins, we focused this study on enterocin S37, a bacteriocin produced by Enterococcus faecalis S37. We observed dose-dependent cytotoxicity toward undifferentiated Caco-2/TC7 cells. Moreover, no significant effect on differentiated monolayer Caco-2/TC7 and no apoptotic features were observed when cells were treated with 10 μg/ml of enterocin S37. The results obtained indicate possible safe use of enterocin S37 in the gastrointestinal tract of animals to prevent pathogen invasion and/or infection. Copyright © 2010 Institut Pasteur. Published by Elsevier SAS. All rights reserved.
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Joosten, H M; Nunez, M; Devreese, B; Van Beeumen, J; Marugg, J D
1996-01-01
A simple two-step procedure was developed to obtain pure enterocin 4, a bacteriocin produced by Enterococcus faecalis INIA 4. Chemical and genetic characterization revealed that the primary structure of enterocin 4 is identical to that of peptide antibiotic AS-48 from Enterococcus faecalis S-48. In contrast to the reported inhibitory spectrum of AS-48, enterocin 4 displayed no activity against gram-negative bacteria. PMID:8900014
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Joosten, H M; Nunez, M; Devreese, B; Van Beeumen, J; Marugg, J D
1996-01-01
A simple two-step procedure was developed to obtain pure enterocin 4, a bacteriocin produced by Enterococcus faecalis INIA 4. Chemical and genetic characterization revealed that the primary structure of enterocin 4 is identical to that of peptide antibiotic AS-48 from Enterococcus faecalis S-48. In contrast to the reported inhibitory spectrum of AS-48, enterocin 4 displayed no activity against gram-negative bacteria.
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[Enterocin typing of enterococci].
Sedov, V I
1978-09-01
The author worked out a method of enterocinotyping on enterococci. A possibility of enterococcus typing by means of a set of enterocinogenic enterococcus strains was shown. A mobile enterococcus 4 (10 p) strain, possessing a high antagonistic activity, is suggested for enterococcus identification. Differentiation of enterococcus species by the enterocine sensitivity proved to be impossible.
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Enterocin P Selectively Dissipates the Membrane Potential of Enterococcus faecium T136
Herranz, C.; Chen, Y.; Chung, H.-J.; Cintas, L. M.; Hernández, P. E.; Montville, T. J.; Chikindas, M. L.
2001-01-01
Enterocin P is a pediocin-like, broad-spectrum bacteriocin which displays a strong inhibitory activity against Listeria monocytogenes. The bacteriocin was purified from the culture supernatant of Enterococcus faecium P13, and its molecular mechanism of action against the sensitive strain E. faecium T136 was evaluated. Although enterocin P caused significant reduction of the membrane potential (ΔΨ) and the intracellular ATP pool of the indicator organism, the pH gradient (ΔpH) component of the proton motive force (Δp) was not dissipated. By contrast, enterocin P caused carboxyfluorescein efflux from E. faecium T136-derived liposomes. PMID:11282622
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In vitro biosynthesis of unnatural enterocin and wailupemycin polyketides.
Kalaitzis, John A; Cheng, Qian; Thomas, Paul M; Kelleher, Neil L; Moore, Bradley S
2009-03-27
Nature has evolved finely tuned strategies to synthesize rare and complex natural products such as the enterocin family of polyketides from the marine bacterium Streptomyces maritimus. Herein we report the directed ex vivo multienzyme syntheses of 24 unnatural 5-deoxyenterocin and wailupemycin F and G analogues, 18 of which are new. We have generated molecular diversity by priming the enterocin biosynthesis enzymes with unnatural substrates and have illustrated further the uniqueness of this type II polyketide synthase by way of exploiting its unusual starter unit biosynthesis pathways.
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Directory of Open Access Journals (Sweden)
M. Pogány Simonová
2017-03-01
Full Text Available Information concerning the virulence factor genes and antibiotic resistance of rabbit enterococci is limited, so in this study we tested the virulence factor genes in Enterococcus faecalis strains from rabbits. Moreover, their resistance/sensitivity to antibiotics and sensitivity to enterocins was also tested, with the aim of contributing to our enterocin spectra study and to indicate the possibility of enterocin application in prevention or contaminant elimination in rabbit husbandry. A total of 144 rabbit samples were treated using a standard microbiological method. Thirty-one pure colonies of the species Enterococcus faecalis were identified, using the MALDI-TOF identification system and confirmed using phenotyping, among which 15 strains were virulence factor gene absent. The gelE gene was the most detected (42%; however, the expression of gelatinase phenotype did not always correlate with the detection of gelE. Strains did not show ß-haemolysis and were mostly resistant to tested antibiotics, but sensitive to enterocins (Ent, mainly to Ents EK13=A (P, 2019 and Ent M. Rabbit E. faecalis strains displayed antibiotic resistant traits and the presence of expressed and silent virulence genes, but they showed high levels of sensitivity to natural antimicrobials-enterocins, which indicates the possible prevention of multidrug and virulent enterococcal contaminants by enterocins.
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Inhibition of Bacillus licheniformis LMG 19409 from ropy cider by enterocin AS-48.
Grande, M J; Lucas, R; Abriouel, H; Valdivia, E; Ben Omar, N; Maqueda, M; Martínez-Cañamero, M; Gálvez, A
2006-08-01
To determine the activity of enterocin AS-48 against ropy-forming Bacillus licheniformis from cider. Enterocin AS-48 was tested on B. licheniformis LMG 19409 from ropy cider in MRS-G broth, fresh-made apple juice and in two commercial apple ciders (A and B). Bacillus licheniformis was rapidly inactivated in MRS-G by 0.5 microg ml(-1)AS-48 and in fresh-made apple juice by 3 microg ml(-1). Concentration-dependent inactivation of this bacterium in two commercial apple ciders (A and B) stored at 4, 15 and 30 degrees C for 15 days was also demonstrated. Counts from heat-activated endospores in cider A plus AS-48 decreased very slowly. Application of combined treatments of heat (95 degrees C) and enterocin AS-48 reduced the time required to achieved complete inactivation of intact spores in cider A to 4 min for 6 microg ml(-1) and to 1 min for 12 microg ml(-1). D and z values also decreased as the bacteriocin concentration increased. Enterocin AS-48 can inhibit ropy-forming B. licheniformis in apple cider and increase the heat sensitivity of spores. Results from this study support the potential use of enterocin AS-48 to control B. licheniformis in apple cider.
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Grande Burgos, Mar?a Jos?; P?rez Pulido, Rub?n; L?pez Aguayo, Mar?a del Carmen; G?lvez, Antonio; Lucas, Rosario
2014-01-01
Enterocin AS-48 is a circular bacteriocin produced by Enterococcus. It contains a 70 amino acid-residue chain circularized by a head-to-tail peptide bond. The conformation of enterocin AS-48 is arranged into five alpha-helices with a compact globular structure. Enterocin AS-48 has a wide inhibitory spectrum on Gram-positive bacteria. Sensitivity of Gram-negative bacteria increases in combination with outer-membrane permeabilizing treatments. Eukaryotic cells are bacteriocin-resistant. This ...
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Mareková, Mária; Lauková, Andrea; Skaugen, Morten; Nes, Ingolf
2007-08-01
The new bacteriocin, termed enterocin M, produced by Enterococcus faecium AL 41 showed a wide spectrum of inhibitory activity against the indicator organisms from different sources. It was purified by (NH4)2SO4 precipitation, cation-exchange chromatography and reverse phase chromatography (FPLC). The purified peptide was sequenced by N-terminal amino acid Edman degradation and a mass spectrometry analysis was performed. By combining the data obtained from amino acid sequence (39 N-terminal amino acid residues was determined) and the molecular weight (determined to be 4628 Da) it was concluded that the purified enterocin M is a new bacteriocin, which is very similar to enterocin P. However, its molecular weight is different from enterocin P (4701.25). Of the first 39 N-terminal residues of enterocin M, valine was found in position 20 and a lysine in position 35, while enterocin P has tryptophane residues in these positions.
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Inhibition of toxicogenic Bacillus cereus in rice-based foods by enterocin AS-48.
Grande, Maria J; Lucas, Rosario; Abriouel, Hikmate; Valdivia, Eva; Omar, Nabil Ben; Maqueda, Mercedes; Martínez-Bueno, Manuel; Martínez-Cañamero, Magdalena; Gálvez, Antonio
2006-02-01
The antimicrobial effect of the broad-spectrum bacteriocin enterocin AS-48 against the toxicogenic psychrotrophic strain Bacillus cereus LWL1 has been investigated in a model food system consisting of boiled rice and in a commercial infant rice-based gruel dissolved in whole milk stored at temperatures of 37 degrees C, 15 degrees C and 6 degrees C. In food samples supplemented with enterocin AS-48 (in a concentration range of 20-35 mug/ml), viable cell counts decreased rapidly over incubation time, depending on the bacteriocin concentration, the temperature of incubation and the food sample. Enterotoxin production at 37 degrees C was also inhibited. Heat sensitivity of endospores increased markedly in food samples supplemented with enterocin AS-48: inactivation of endospores was achieved by heating for 1 min at 90 degrees C in boiled rice or at 95 degrees C in rice-based gruel. Activity of enterocin AS-48 in rice gruel was potentiated by sodium lactate in a concentration-dependent way.
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Directory of Open Access Journals (Sweden)
Andrea Lauková1,
2017-10-01
Full Text Available Enterococcus faecium EM41 is an isolate from ostrich faeces. It produces a thermo-stable proteinaceous substance, bacteriocin (enterocin EM41 with the highest inhibition activity in late logarithmic phase of growth (25 600 AU/ml. This strain and its enterocin have not been previously tested in animals. Lohmann Brown laying hens (aged 45 weeks were involved in this model/pilot experiment, divided into 3 groups 6 birds in each. E. faecium EM41 applied was a variant treated with rifampicin (109 cfu/ml, dose 400 μl/animal/day to differentiate it from the other enterococci. Partially-purified enterocin EM41 (Ent EM41, dose 40 μl/animal/day and its producer were applied to water for 21 days. The experiment lasted 35 days. Sampling was performed at days 0 - 1, 21 (3 weeks of additive application, 35 (2 weeks after cessation of additive application from every bird. E. faecium EM41 sufficiently colonized the intestinal tract of laying hens from the initial concentration 109 cfu/g, its count reached 4.30 log cfu/g at day 21. PCR genotypization confirmed the identity of the EM41 strain with the species Enterococcus faecium. E. faecium EM41 and its enterocin EM41 showed antimicrobial effects demonstrated by reduction of coagulase-positive and coagulase-negative staphylococci, coliforms, Pseudomonas spp., Aeromonas spp. and Campylobacter spp. The hens were Salmonella spp. free. After administration of both additives, phagocytic activity was stimulated with a significant increase. The additives did not negatively influence biochemical and haematological parameters or weight gains.
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Al-Seraih, Alaa; Belguesmia, Yanath; Baah, John; Szunerits, Sabine; Boukherroub, Rabah; Drider, Djamel
2017-02-01
Enterococcus faecalis B3A-B3B produces the bacteriocin B3A-B3B with activity against Listeria monocytogenes, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium perfringens, but apparently not against fungi or Gram-negative bacteria, except for Salmonella Newport. B3A-B3B enterocin has two different nucleotides but similar amino acid composition to the class IIb MR10A-MR10B enterocin. B3A-B3B consists of two peptides of predicted molecular mass of 5176.31 Da (B3A) and 5182.21 Da (B3B). Importantly, B3A-B3B impeded biofilm formation of the foodborne pathogen L. monocytogenes 162 grown on stainless steel. The antimicrobial treatment of stainless steel with nisin (1 or 16 mg ml -1 ) decreased the cell numbers by about 2 log CFU ml -1 , thereby impeding the biofilm formation by L. monocytogenes 162 or its nisin-resistant derivative strain L. monocytogenes 162R. Furthermore, the combination of nisin and B3A-B3B enterocin reduced the MIC required to inhibit this pathogen grown in planktonic or biofilm cultures.
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Directory of Open Access Journals (Sweden)
María José Grande Burgos
2014-12-01
Full Text Available Enterocin AS-48 is a circular bacteriocin produced by Enterococcus. It contains a 70 amino acid-residue chain circularized by a head-to-tail peptide bond. The conformation of enterocin AS-48 is arranged into five alpha-helices with a compact globular structure. Enterocin AS-48 has a wide inhibitory spectrum on Gram-positive bacteria. Sensitivity of Gram-negative bacteria increases in combination with outer-membrane permeabilizing treatments. Eukaryotic cells are bacteriocin-resistant. This cationic peptide inserts into bacterial membranes and causes membrane permeabilization, leading ultimately to cell death. Microarray analysis revealed sets of up-regulated and down-regulated genes in Bacillus cereus cells treated with sublethal bacteriocin concentration. Enterocin AS-48 can be purified in two steps or prepared as lyophilized powder from cultures in whey-based substrates. The potential applications of enterocin AS-48 as a food biopreservative have been corroborated against foodborne pathogens and/or toxigenic bacteria (Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Escherichia coli, Salmonella enterica and spoilage bacteria (Alicyclobacillus acidoterrestris, Bacillus spp., Paenibacillus spp., Geobacillus stearothermophilus, Brochothrix thermosphacta, Staphylococcus carnosus, Lactobacillus sakei and other spoilage lactic acid bacteria. The efficacy of enterocin AS-48 in food systems increases greatly in combination with chemical preservatives, essential oils, phenolic compounds, and physico-chemical treatments such as sublethal heat, high-intensity pulsed-electric fields or high hydrostatic pressure.
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Grande Burgos, María José; Pulido, Rubén Pérez; Del Carmen López Aguayo, María; Gálvez, Antonio; Lucas, Rosario
2014-12-08
Enterocin AS-48 is a circular bacteriocin produced by Enterococcus. It contains a 70 amino acid-residue chain circularized by a head-to-tail peptide bond. The conformation of enterocin AS-48 is arranged into five alpha-helices with a compact globular structure. Enterocin AS-48 has a wide inhibitory spectrum on Gram-positive bacteria. Sensitivity of Gram-negative bacteria increases in combination with outer-membrane permeabilizing treatments. Eukaryotic cells are bacteriocin-resistant. This cationic peptide inserts into bacterial membranes and causes membrane permeabilization, leading ultimately to cell death. Microarray analysis revealed sets of up-regulated and down-regulated genes in Bacillus cereus cells treated with sublethal bacteriocin concentration. Enterocin AS-48 can be purified in two steps or prepared as lyophilized powder from cultures in whey-based substrates. The potential applications of enterocin AS-48 as a food biopreservative have been corroborated against foodborne pathogens and/or toxigenic bacteria (Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Escherichia coli, Salmonella enterica) and spoilage bacteria (Alicyclobacillus acidoterrestris, Bacillus spp., Paenibacillus spp., Geobacillus stearothermophilus, Brochothrix thermosphacta, Staphylococcus carnosus, Lactobacillus sakei and other spoilage lactic acid bacteria). The efficacy of enterocin AS-48 in food systems increases greatly in combination with chemical preservatives, essential oils, phenolic compounds, and physico-chemical treatments such as sublethal heat, high-intensity pulsed-electric fields or high hydrostatic pressure.
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Martinez, JM; Kok, J; Sanders, JW; Hernandez, PE
Antibodies against enterocin A were obtained by immunization of rabbits with synthetic peptides PH4 and PH5 designed, respectively, on the N- and C-terminal amino acid sequences of enterocin A and conjugated to the carrier protein KLH, Anti-PH4-KLH antibodies not only recognized enterocin A but also
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In Vitro Biosynthesis of Unnatural Enterocin and Wailupemycin Polyketides¥
Kalaitzis, John A.; Cheng, Qian; Thomas, Paul M.; Kelleher, Neil L.; Moore, Bradley S.
2009-01-01
Nature has evolved finely tuned strategies to synthesize rare and complex natural products such as the enterocin family of polyketides from the marine bacterium Streptomyces maritimus. Herein we report the directed ex vivo multienzyme syntheses of 24 unnatural 5-deoxyenterocin and wailupemycin F and G analogues, 18 of which are new. We have generated molecular diversity by priming the enterocin biosynthesis enzymes with unnatural substrates and have illustrated further the uniqueness of this type II polyketide synthase by way of exploiting its unusual starter unit biosynthesis pathways. PMID:19215142
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Liu, Hui; Zhang, Lanwei; Yi, Huaxi; Han, Xue; Gao, Wei; Chi, Chunliang; Song, Wei; Li, Haiying; Liu, Chunguang
2016-02-01
An enterocin-producing Enterococcus faecium T1 was isolated from Chinese Tibet cheese. The enterocin was purified by SP-Sepharose and reversed phase HPLC. It was identified as unique from other reported bacteriocins based on molecular weight (4629 Da) and amino acid compositions; therefore it was subsequently named enterocin T1. Enterocin T1 was stable at 80-100 °C and over a wide pH range, pH 3.0-10.0. Protease sensitivity was observed to trypsin, pepsin, papain, proteinase K, and pronase E. Importantly, enterocin T1 was observed to inhibit the growth of numerous Gram-negative and Gram-positive bacteria including Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhimurium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Listeria monocytogenes. Take together, these results suggest that enterocin T1 is a novel bacteriocin with the potential to be used as a bio-preservative to control Pseudomonas spp. in food.
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Kalaitzis, John A
2013-01-01
The marine actinomycete Streptomyces maritimus produces a structurally diverse set of unusual polyketide natural products including the major metabolite enterocin. Investigations of enterocin biosynthesis revealed that the unique carbon skeleton is derived from an aromatic polyketide pathway which is genetically coded by the 21.3 kb enc gene cluster in S. maritimus. Characterization of the enc biosynthesis gene cluster and subsequent manipulation of it via heterologous expression and/or mutagenesis enabled the discovery of other enc-based metabolites that were produced in only very minor amounts in the wild type. Also described are techniques used to harness the enterocin biosynthetic machinery in order to generate unnatural enc-derived polyketide analogues. This review focuses upon the molecular methods used in combination with classical natural products detection and isolation techniques to access minor metabolites of the S. maritimus secondary metabolome.
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McClintock, Maria K; Kaznessis, Yiannis N; Hackel, Benjamin J
2016-02-01
Vancomycin-resistant Enterococci infections are a significant clinical problem. One proposed solution is to use probiotics, such as lactic acid bacteria, to produce antimicrobial peptides at the site of infection. Enterocin A, a class 2a bacteriocin, exhibits inhibitory activity against E. faecium and E. faecalis, which account for 86% of vancomycin-resistant Enterococci infections. In this study, we aimed to engineer enterocin A mutants with enhanced potency within a lactic acid bacterial production system. Peptide mutants resulting from saturation mutagenesis at sites A24 and T27 were efficiently screened in a 96-well plate assay for inhibition of pathogen growth. Several mutants exhibit increased potency relative to wild-type enterocin A in both liquid- and solid-medium growth assays. In particular, A24P and T27G exhibit enhanced inhibition of multiple strains of E. faecium and E. faecalis, including clinically isolated vancomycin-resistant strains. A24P and T27G enhance killing of E. faecium 8 by 13 ± 3- and 18 ± 4-fold, respectively. The engineered enterocin A/lactic acid bacteria systems offer significant potential to combat antibiotic-resistant infections. © 2015 Wiley Periodicals, Inc.
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Directory of Open Access Journals (Sweden)
Zeliha Yıldırım
2014-01-01
Full Text Available In this study, the effects of food preservative p-hydroxybenzoic acid and propyl-paraben on the inhibitory activity of enterocin KP produced by Enterococcus faecalis KP were determined. Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella Typhimurium, resistant to enterocin KP bacteriocin, were used as target organisms. The inhibitor activity of enterosin KP (1600 AU/ml alone or in combination with p-hydroxybenzoic acid (%0.1-0.3 and propyl-paraben (%0.008-0.16 on the growth of Staphylococcus aureus, Escherichia coli O157:H7 and Salmonella Typhimurium were determined. The inhibitory activity of enterocin KP was increased when used in combination with p-hydroxybenzoic acid and propyl-paraben at concentrations of 0.1-0.3% and 0.008-0.016%, respectively. Furthermore, Staphylococcus aureus, E. coli O157:H7 and Salmonella Typhimurium became sensitive to enterocin KP. In conclusion, the use of enterocin KP in combination with other food preservatives principles resulted in an increase in its inhibitory activity and spectrum.
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Dündar, Halil; Atakay, Mehmet; Çelikbıçak, Ömür; Salih, Bekir; Bozoğlu, Faruk
2015-01-01
This study aimed to compare two different approaches for the purification of enterocin B from Enterococcus faecium strain W3 based on the observation that the bacteriocin was found both in cell associated form and in culture supernatant. The first approach employed ammonium sulfate precipitation, cation-exchange chromatography, and sequential reverse-phase high-performance liquid chromatography. The latter approach exploited a pH-mediated cell adsorption-desorption method to extract cell-bound bacteriocin, and one run of reverse-phase chromatography. The first method resulted in purification of enterocin B with a recovery of 4% of the initial bacteriocin activity found in culture supernatant. MALDI-TOF MS analysis and de novo peptide sequencing of the purified bacteriocin confirmed that the active peptide was enterocin B. The second method achieved the purification of enterocin B with a higher recovery (16%) and enabled us to achieve pure bacteriocin within a shorter period of time by avoiding time consuming purification protocols. The purity and identity of the active peptide were confirmed again by matrix-assisted laser desorption/ionization time-of flight (MALDI-TOF) mass spectrometry (MS) analysis. Although both approaches were satisfactory to obtain a sufficient amount of enterocin B for use in MS and amino acid sequence analysis, the latter was proved to be applicable in large-scale and rapid purification of enterocin B.
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Grande Burgos, M.J.; Kovács, Á.T.; Miro?czuk, A.M.; Abriouel, H.; Gálvez, A.; Kuipers, O.P.
2009-01-01
Background: Enterocin AS-48 is produced by Enterococcus faecalis S48 to compete with other bacteria in their environment. Due to its activity against various Gram positive and some Gram negative bacteria it has clear potential for use as a food preservative. Here, we studied the effect of enterocin
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Izquierdo, Esther; Wagner, Camille; Marchioni, Eric; Aoude-Werner, Dalal; Ennahar, Saïd
2009-01-01
Enterococcus faecalis WHE 96, a strain isolated from soft cheese based on its anti-Listeria activity, produced a 5,494-Da bacteriocin that was purified to homogeneity by ultrafiltration and cation-exchange and reversed-phase chromatographies. The amino acid sequence of this bacteriocin, named enterocin 96, was determined by Edman degradation, and its structural gene was sequenced, revealing a double-glycine leader peptide. After a comparison with other bacteriocins, it was shown that enterocin 96 was a new class II bacteriocin that showed very little similarity with known structures. Enterocin 96 was indeed a new bacteriocin belonging to class II bacteriocins. The activity spectrum of enterocin 96 covered a wide range of bacteria, with strong activity against most gram-positive strains but very little or no activity against gram-negative strains. PMID:19411428
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Izquierdo, Esther; Wagner, Camille; Marchioni, Eric; Aoude-Werner, Dalal; Ennahar, Saïd
2009-07-01
Enterococcus faecalis WHE 96, a strain isolated from soft cheese based on its anti-Listeria activity, produced a 5,494-Da bacteriocin that was purified to homogeneity by ultrafiltration and cation-exchange and reversed-phase chromatographies. The amino acid sequence of this bacteriocin, named enterocin 96, was determined by Edman degradation, and its structural gene was sequenced, revealing a double-glycine leader peptide. After a comparison with other bacteriocins, it was shown that enterocin 96 was a new class II bacteriocin that showed very little similarity with known structures. Enterocin 96 was indeed a new bacteriocin belonging to class II bacteriocins. The activity spectrum of enterocin 96 covered a wide range of bacteria, with strong activity against most gram-positive strains but very little or no activity against gram-negative strains.
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Xu, Dong-Bo; Ma, Min; Deng, Zi-Xin; Hong, Kui
2015-07-01
The type II polyketide synthase (PKS) natural product enterocin (1) was isolated from a mangrove-derived novel species Streptomyces qinglanensis 172205 guided by genome sequence, and its putative biosynthetic gene cluster was revealed. Its natural analogues 5-deoxyenterocin (2) and wailupemycin A-C (3-5) were also identified by tandem mass spectrometry. By feeding experiments with aryl acids, strain 172205 was proved to incorporate partial exogenous starter units into enterocin- and wailupemycin-based analogues, thus being a new and suitable microorganism for engineering unnatural enc-derived polyketide metabolites. In addition, biological assays indicated that enterocin showed obvious inhibitory activity against β-amyloid protein (Aβ1-42) fibrillation and moderate cytotoxicity against HeLa and HepG2 for the first time.
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Masias, Emilse; Dupuy, Fernando G; da Silva Sanches, Paulo Ricardo; Farizano, Juan Vicente; Cilli, Eduardo; Bellomio, Augusto; Saavedra, Lucila; Minahk, Carlos
2017-07-01
Enterocin CRL35 is a class IIa bacteriocin with anti-Listeria activity. Resistance to these peptides has been associated with either the downregulation of the receptor expression or changes in the membrane and cell walls. The scope of the present work was to characterize enterocin CRL35 resistant Listeria strains with MICs more than 10,000 times higher than the MIC of the WT sensitive strain. Listeria monocytogenes INS7 resistant isolates R2 and R3 were characterized by 16S RNA gene sequencing and rep-PCR. Bacterial growth kinetic was studied in different culture media. Plasma membranes of sensitive and resistant bacteria were characterized by FTIR and Langmuir monolayer techniques. The growth kinetic of the resistant isolates was slower as compared to the parental strain in TSB medium. Moreover, the resistant isolates barely grew in a glucose-based synthetic medium, suggesting that these cells had a major alteration in glucose transport. Resistant bacteria also had alterations in their cell wall and, most importantly, membrane lipids. In fact, even though enterocin CRL35 was able to bind to the membrane-water interface of both resistant and parental sensitive strains, this peptide was only able to get inserted into the latter membranes. These results indicate that bacteriocin receptor is altered in combination with membrane structural modifications in enterocin CRL35-resistant L. monocytogenes strains. Highly enterocin CRL35-resistant isolates derived from Listeria monocytogenes INS7 have not only an impaired glucose transport but also display structural changes in the hydrophobic core of their plasma membranes. Copyright © 2017. Published by Elsevier B.V.
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Aymerich, T; Holo, H; Håvarstein, L S; Hugas, M; Garriga, M; Nes, I F
1996-01-01
A new bacteriocin has been isolated from an Enterococcus faecium strain. The bacteriocin, termed enterocin A, was purified to homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, N-terminal amino acid sequencing, and mass spectrometry analysis. By combining the data obtained from amino acid and DNA sequencing, the primary structure of enterocin A was determined. It consists of 47 amino acid residues, and the molecular weight was calculated to be 4,829, assuming that the four cysteine residues form intramolecular disulfide bridges. This molecular weight was confirmed by mass spectrometry analysis. The amino acid sequence of enterocin A shared significant homology with a group of bacteriocins (now termed pediocin-like bacteriocins) isolated from a variety of lactic acid-producing bacteria, which include members of the genera Lactobacillus, Pediococcus, Leuconostoc, and Carnobacterium. Sequencing of the structural gene of enterocin A, which is located on the bacterial chromosome, revealed an N-terminal leader sequence of 18 amino acid residues, which was removed during the maturation process. The enterocin A leader belongs to the double-glycine leaders which are found among most other small nonlantibiotic bacteriocins, some lantibiotics, and colicin V. Downstream of the enterocin A gene was located a second open reading frame, encoding a putative protein of 103 amino acid residues. This gene may encode the immunity factor of enterocin A, and it shares 40% identity with a similar open reading frame in the operon of leucocin AUL 187, another pediocin-like bacteriocin. PMID:8633865
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Gupta, Aabha; Tiwari, Santosh Kumar; Netrebov, Victoria; Chikindas, Michael L
2016-09-01
Enterocin LD3 was purified using activity-guided multistep chromatography techniques such as cation-exchange and gel-filtration chromatography. The preparation's purity was tested using reverse-phase ultra-performance liquid chromatography. The specific activity was tested to be 187.5 AU µg(-1) with 13-fold purification. Purified enterocin LD3 was heat stable up to 121 °C (at 15 psi pressure) and pH 2-6. The activity was lost in the presence of papain, reduced by proteinase K, pepsin and trypsin, but was unaffected by amylase and lipase, suggesting proteinaceous nature of the compound and no role of carbohydrate and lipid moieties in the activity. MALDI-TOF/MS analysis of purified enterocin LD3 resolved m/z 4114.6, and N-terminal amino acid sequence was found to be H2NQGGQANQ-COOH suggesting a new bacteriocin. Dissipation of membrane potential, loss of internal ATP and bactericidal effect were recorded when indicator strain Micrococcus luteus was treated with enterocin LD3. It inhibited Gram-positive and Gram-negative bacteria including human pathogens such as Staphylococcus aureus, Pseudomonas fluorescens, Pseudomonas aeruginosa, Salmonella typhi, Shigella flexneri, Listeria monocytogenes, Escherichia coli O157:H7, E. coli (urogenic, a clinical isolate) and Vibrio sp. These properties of purified enterocin LD3 suggest its applications as a food biopreservative and as an alternative to clinical antibiotics.
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Cobo Molinos, Antonio; Abriouel, Hikmate; López, Rosario Lucas; Valdivia, Eva; Omar, Nabil Ben; Gálvez, Antonio
2008-08-01
Enterocin AS-48 was tested for decontamination of soybean sprouts against Gram-negative bacteria. Although treatment with bacteriocin alone had no effect on Salmonella enterica, a synergistic antimicrobial effect was detected at pH 9.0 and in combination with moderate heat treatment. Greatest inactivation was achieved for sprouts heated for 5 min at 65 degrees C in an alkaline (pH 9.0) enterocin AS-48 solution of 25 microg/ml. Bactericidal activity against S. enterica increased greatly when enterocin AS-48 was used in washing solutions in combination with several chemical compounds: EDTA, lactic acid, peracetic acid, polyphosphoric acid, sodium hypochlorite, hexadecylpyridinium chloride, propyl-p-hydroxybenzoate, and hydrocinnamic acid. The combined treatment of enterocin AS-48 and polyphosphoric acid was tested against several other Gram-negative bacteria inoculated on sprouts. The bacteria tested showed great differences in sensitivity to polyphosphoric acid, but synergism with enterocin AS-48 was confirmed in all cases. Combinations of enterocin AS-48 (25 microg/ml) and polyphosphoric acid in a concentration range of 0.1 to 2.0% significantly reduced or inhibited growth of the populations of S. enterica, Escherichia coli O157:H7, Shigella spp., Enterobacter aerogenes, Yersinia enterocolitica, Aeromonas hydrophila and Pseudomonas fluorescens in sprout samples stored at 6 degrees C and 15 degrees C. The combined treatment could therefore be applied to reduce the risks of Gram-negative pathogenic as well as spoilage bacteria on sprouts.
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Vandera, Elpiniki; Lianou, Alexandra; Kakouri, Athanasia; Feng, Jinbo; Koukkou, Anna-Irini; Samelis, John
2017-01-01
Enterococcus faecium KE82, isolated from traditional Greek Graviera cheese, was identified in pure broth cultures in vitro as a multiple enterocin-producing bacterial strain possessing the structural entA, entB, and entP enterocin genes. E. faecium KE82 was further assessed for in situ antilisterial activity in raw milk (RM) and commercially thermized milk (TM; 63°C for 30 s) in the presence of the indigenous microbiota and in sterile raw milk (SRM; 121°C for 5 min) with or without the addition of two commercial starter culture (CSC) strains Streptococcus thermophilus and Lactococcus lactis . Growth of Listeria monocytogenes was completely inhibited in RM incubated at 37°C for 6 h, whereas the pathogen was significantly inactivated in RM+KE82 samples during further incubation at 18°C for 66 h. In contrast, L. monocytogenes levels increased by approximately 2 log CFU/ml in TM, but in TM+KE82 samples, pathogen growth was retarded during the first 6 h at 37°C followed by growth cessation and partial inactivation at 18°C. After 48 to 72 h, growth of L. monocytogenes in SRM+CSC samples decreased by 4 to 5 log CFU/ml compared with the SRM control, whereas additional 10-fold decreases in the pathogen were observed in SRM+CSC+KE82 samples. Reverse transcription PCR analysis of SRM+KE82 and SRM+CSC+KE82 samples confirmed that the entA and entB genes were transcribed, but entP gene transcription was not detected. All RM and SRM samples inoculated with E. faecium KE82 displayed strong in situ inhibitory activity against L. monocytogenes in well diffusion bioassays, whereas activity was weaker to undetectable in comparable or additional TM+KE82 samples; no milk sample without E. faecium KE82 had activity against L. monocytogenes . The findings of this study indicate that E. faecium KE82 is an antilisterial agent that could be used in traditional dairy foods because it concomitantly produces enterocins A and B in situ in milk.
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Himeno, Kohei; Rosengren, K Johan; Inoue, Tomoko; Perez, Rodney H; Colgrave, Michelle L; Lee, Han Siean; Chan, Lai Y; Henriques, Sónia Troeira; Fujita, Koji; Ishibashi, Naoki; Zendo, Takeshi; Wilaipun, Pongtep; Nakayama, Jiro; Leelawatcharamas, Vichien; Jikuya, Hiroyuki; Craik, David J; Sonomoto, Kenji
2015-08-11
Enterocin NKR-5-3B, one of the multiple bacteriocins produced by Enterococcus faecium NKR-5-3, is a 64-amino acid novel circular bacteriocin that displays broad-spectrum antimicrobial activity. Here we report the identification, characterization, and three-dimensional nuclear magnetic resonance solution structure determination of enterocin NKR-5-3B. Enterocin NKR-5-3B is characterized by four helical segments that enclose a compact hydrophobic core, which together with its circular backbone impart high stability and structural integrity. We also report the corresponding structural gene, enkB, that encodes an 87-amino acid precursor peptide that undergoes a yet to be described enzymatic processing that involves adjacent cleavage and ligation of Leu(24) and Trp(87) to yield the mature (circular) enterocin NKR-5-3B.
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Directory of Open Access Journals (Sweden)
Kraiyot Saelim
2015-06-01
Full Text Available Enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from the chicken gastrointestinal tract was active in the wide range of pH 2-10 and temperature 30-100°C and sensitive to proteolytic enzymes and -amylase. It remained active after storage at -20°C for 2 months. Moreover, enterocin CE5-1 showed antibacterial activity against lactobacilli, bacilli, listeria, staphylococci and enterococci, especially antibiotic-resistant enterococci. In vitro study of enterocin CE5-1 decreased the population of Ent. faecalis VanB from 6.03 to 4.03 log CFU/ml. The lethal mode of action of enterocin CE5-1 appeared to be pore and filament formation in the cell wall. PCR sequencing analysis revealed the presence of two open reading frames (ORFs, containing enterocin CE5-1 (entCE5-1 and enterocin immunity (entI gene. Therefore, enterocin CE5-1 from Ent. faecium CE5-1 could possibly be used as an antimicrobial agent to control foodborne pathogen, spoilage bacteria and antibiotic-resistant enterococci in foods, feeds and the environments.
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Jiménez, Juan J; Borrero, Juan; Gútiez, Loreto; Arbulu, Sara; Herranz, Carmen; Cintas, Luis M; Hernández, Pablo E
2014-06-01
The use of synthetic genes may constitute a successful approach for the heterologous production and functional expression of bacterial antimicrobial peptides (bacteriocins) by recombinant yeasts. In this work, synthetic genes with adapted codon usage designed from the mature amino acid sequence of the bacteriocin enterocin A (EntA), produced by Enterococcus faecium T136, and the mature bacteriocin E 50-52 (BacE50-52), produced by E. faecium NRRL B-32746, were synthesized. The synthetic entA and bacE50-52 were cloned into the protein expression vectors pPICZαA and pKLAC2 for transformation of derived vectors into Pichia pastoris X-33 and Kluyveromyces lactis GG799, respectively. The recombinant vectors were linearized and transformed into competent cells selecting for P. pastoris X-33EAS (entA), P. pastoris X-33BE50-52S (bacE50-52), K. lactis GG799EAS (entA), and K. lactis GG799BE50-52S (bacE50-52). P. pastoris X-33EAS and K. lactis GG799EAS, but not P. pastoris X-33BE50-52S and K. lactis GG799BE50-52S, showed antimicrobial activity in their supernatants. However, purification of the supernatants of the producer yeasts permitted recovery of the bacteriocins EntA and BacE50-52. Both purified bacteriocins were active against Gram-positive bacteria such as Listeria monocytogenes but not against Gram-negative bacteria, including Campylobacter jejuni.
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O’Keeffe, Triona; Hill, Colin; Ross, R. Paul
1999-01-01
Enterocin A is a small, heat-stable, antilisterial bacteriocin produced by Enterococcus faecium DPC1146. The sequence of a 10,879-bp chromosomal region containing at least 12 open reading frames (ORFs), 7 of which are predicted to play a role in enterocin biosynthesis, is presented. The genes entA, entI, and entF encode the enterocin A prepeptide, the putative immunity protein, and the induction factor prepeptide, respectively. The deduced proteins EntK and EntR resemble the histidine kinase and response regulator proteins of two-component signal transducing systems of the AgrC-AgrA type. The predicted proteins EntT and EntD are homologous to ABC (ATP-binding cassette) transporters and accessory factors, respectively, of several other bacteriocin systems and to proteins implicated in the signal-sequence-independent export of Escherichia coli hemolysin A. Immediately downstream of the entT and entD genes are two ORFs, the product of one of which, ORF4, is very similar to the product of the yteI gene of Bacillus subtilis and to E. coli protease IV, a signal peptide peptidase known to be involved in outer membrane lipoprotein export. Another potential bacteriocin is encoded in the opposite direction to the other genes in the enterocin cluster. This putative bacteriocin-like peptide is similar to LafX, one of the components of the lactacin F complex. A deletion which included one of two direct repeats upstream of the entA gene abolished enterocin A activity, immunity, and ability to induce bacteriocin production. Transposon insertion upstream of the entF gene also had the same effect, but this mutant could be complemented by exogenously supplied induction factor. The putative EntI peptide was shown to be involved in the immunity to enterocin A. Cloning of a 10.5-kb amplicon comprising all predicted ORFs and regulatory regions resulted in heterologous production of enterocin A and induction factor in Enterococcus faecalis, while a four-gene construct (entAITD) under the
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Ananou, S; Gálvez, A; Martínez-Bueno, M; Maqueda, M; Valdivia, E
2005-01-01
To determine the effects of outer membrane (OM) permeabilizing agents on the antimicrobial activity of enterocin AS-48 against Escherichia coli O157:H7 CECT 4783 strain in buffer and apple juice. We determined the influence of pH, EDTA, sodium tripolyphosphate (STPP) and heat on E. coli O157:H7 CECT 4783 sensitivity to enterocin AS-48 in buffer and in apple juice. Enterocin AS-48 was not active against intact cells of E. coli O157:H7 CECT 4783 at neutral pH. However, cells sublethally injured by OM permeabilizing agents (EDTA, STPP, pH 5, pH 8.6 and heat) became sensitive to AS-48, decreasing the amount of bacteriocin required for inhibition of E. coli O157:H7 CECT 4783. The results presented indicate that enterocin AS-48 could potentially be applied with a considerably wider range of protective agents, such as OM permeabilizing agents, with increased efficacy in inhibiting E. coli O157:H7. Results from this study support the potential use of enterocin AS-48 to control E. coli O157:H7 in combination with other hurdles.
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Arlindo, Samuel; Calo, Pilar; Franco, Carlos; Prado, Marta; Cepeda, Alberto; Barros-Velázquez, Jorge
2006-12-01
The bacteriocins produced by two lactic acid bacteria isolated from nonfermented fresh meat and fish, respectively, and exhibiting a remarkable antilisterial activity, were characterized. Bacteriocinogenic strains were identified as Enterococcus faecium and the maximum bacteriocin production by both strains was detected in the stationary phase of growth. The activity against Listeria monocytogenes was maintained in pH range of 3-7 and was stable in both strains after heating at 100 or 121 degrees C. The genes coding for enterocin P were detected, isolated, and sequenced in both E. faecium strains. They exhibited DNA/DNA homology in the 87.1-97.2% range with respect to the other four enterocin P genes reported so far. Three single nucleotide polymorphism events, silent at the amino acid level, were detected at nucleotide positions 45 (G/A), 75 (A/G), and 90 (T/C) in E. faecium LHICA 28-4 and may explain the differences reported for those loci in other enterocin P-producing E. faecium strains. This work provides the first description of enterocin P-producing E. faecium strains in nonfermented foodstuffs and, in the case of E. faecium LHICA 51, the first report of an enterocin P-producing strain isolated from fish so far.
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Sec-mediated secretion of bacteriocin enterocin P by Lactococcus lactis
Herranz, C; Driessen, AJM
Most lactic acid bacterium bacteriocins utilize specific leader peptides and dedicated machineries for secretion. In contrast, the enterococcal bacteriocin enterocin P (EntP) contains a typical signal peptide that directs its secretion when heterologously expressed in Lactococcus lactis. Signal
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Sawa, Naruhiko; Wilaipun, Pongtep; Kinoshita, Seisuke; Zendo, Takeshi; Leelawatcharamas, Vichien; Nakayama, Jiro; Sonomoto, Kenji
2012-02-01
Enterococcus faecalis NKR-4-1 isolated from pla-ra produces a novel two-peptide lantibiotic, termed enterocin W, comprising Wα and Wβ. The structure of enterocin W exhibited similarity with that of plantaricin W. The two peptides acted synergistically, and their order of binding to the cell membrane was important for their inhibitory activity.
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Svetoch, E A; Borzilov, A I; Eruslanov, B V; Korobova, O V; Kombarova, T I; Levchuk, V P; Teĭmurazov, M G; Stepanshin, Iu G; Marinin, L I; Diatlov, I A
2011-01-01
The therapeutic efficacy of enterocin S760, a broad spectrum antimicrobial peptide produced by Enterococcus faecium LWP760 was tested on mice infected with Bacillus anthracis M-71 to induce anthrax (second Tsenkovsky's vaccine). Intraperitoneal four-, two- or one-fold administration of the peptide in a dose of 25 mg/kg for 10 days for prophylactic (1 hour after the contamination) and therapeutic (24 hours after the contamination) purposes prevented or cured the infection in 90-100% of the mice versus the 100-percent lethality in the control (untreated animals). The antimicrobial activity of enterocin S760 against B. anthracis M-71 in vivo correlated with activity in vitro. Enterocin S760 is considered a novel promising antimicrobial for the treatment of grampositive and gramnegative infections.
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Directory of Open Access Journals (Sweden)
Mitra Salehi
2014-06-01
Materials and Methods: In this study occurrence of class II enterocin structural gene (enterocin A in a target of 42 Enterococcus faecium strains, isolated from gastrointestinal tract of animal have been surveyed. E. faecium identification and occurrence of enterocin A gene was performed by PCR method. Cell-free neutralized supernatant of gene positive strains was used to test bacteriocin production and antimicrobial spectrum of supernatant was assayed by wall diffusion method on the gram-positive and negative indicators bacteriaResults: Based on our results, 73.8% of isolated strains had enterocin A gene that they inhibited growth of indicator bacteria such as clinical strain of Pseudomonas aeruginosa, Salmonella enteric PTCC1709, Listeria monocytogenes, Bacillus cereus and Bacillus subtilis.Conclusions: Studied enterocins have growth inhibitory spectrum on Gram-positive and Gram-negative bacteria especially against pathogenic bacteria in the gastrointestinal tract. Therefore, these strains have the potential to explore and use as, alternative antimicrobial compound and bio-preservatives in food or feed or as probiotics.
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Gao, Yurong; Li, Benling; Li, Dapeng; Zhang, Liyuan
2016-05-01
To purify and characterize a novel bacteriocin with broad inhibitory spectrum produced by an isolate of Enterococcus faecalis from Chinese fermented cucumber. E. faecalis L11 produced a bacteriocin with antimicrobial activity against both Escherichia coli and Staphylococcus aureus. The amino acid sequence of the purified bacteriocin, enterocin L11, was assayed by Edman degradation method. It differs from other class II bacteriocins and exhibited a broad antimicrobial activity against not only Gram-positive bacteria, including Bacillus subtilis, S. aureus, Listeria monocytogenes, Sarcina flava, Lactobacillus acidophilus, L. plantarum, L. delbrueckii subsp. delbrueckii, L. delbrueckii subsp. bulgaricus and Streptococcus thermophilus, but also some Gram-negative bacteria including Salmonella typhimurium, E. coli and Shigella flexneri. Enterocin L11 retained 91 % of its activity after holding at 121 °C for 30 min. It was also resistant to acids and alkalis. Enterocin L11 is a novel broad-spectrum Class II bacteriocin produced by E. faecalis L11, and may have potential as a food biopreservative.
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Viedma, Pilar Martinez; Abriouel, Hikmate; Omar, Nabil Ben; López, Rosario Lucas; Gálvez, Antonio
2009-09-01
The inhibitory effect of enterocin AS-48 against Staphylococcus aureus was investigated in various types of bakery ingredients. Antibacterial activity greatly depended on the food substrate, ranging from complete inactivation of S. aureus in liquid caramel (in which the bacterium survived poorly) to no significant inhibition (as in vanilla or chocolate creams). Significant reductions of viable counts in the range of 1.8 to 2.7 log units (P enterocin AS-48 was tested in combination with other antimicrobials. Bactericidal activity increased markedly for the combinations of AS-48 and 0.1% eugenol (v/v), 0.5% 2-nitropropanol (v/v), or 3% Nisaplin (w/v). Enterocin AS-48 could be applied in combination with other antimicrobials for preservation of bakery ingredients against S. aureus.
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Klocke, Michael; Mundt, Kerstin; Idler, Frank; Jung, Sabrina; Backhausen, Jan E
2005-06-01
The genes for the bacteriocins enterocin A and B were isolated from Enterococcus faecium ATB 197a. Using the pET37b(+) vector, the enterocin genes were fused to an Escherichia coli specific export signal sequence, a cellulose-binding domain (CBD(cenA)) and a S-tag under the control of a T7lac promotor. The constructs were subsequently cloned into E. coli host cells. The expression of the recombinant enterocins had different effects on both the host cells and other Gram-positive bacteria. The expression of entA in Esc. coli led to the synthesis and secretion of functional active enterocin A fusion proteins, which were active against some Gram-positive indicator bacteria, but did not influence the viability of the host cells. In contrast, the expression of enterocin B fusion proteins led to a reduced viability of the host cells, indicating a misfolding of the protein or interference with the cellular metabolism of Esc. coli. Indicator strains of Gram-positive bacteria were not inhibited by purified enterocin B fusion proteins. However, recombinant enterocin B displayed inhibitory activity after the proteolytic cleavage of the fused peptides.
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Social networks improve leaderless group navigation by facilitating long-distance communication
Directory of Open Access Journals (Sweden)
Nikolai W. F. BODE, A. Jamie WOOD, Daniel W. FRANKS
2012-04-01
Full Text Available Group navigation is of great importance for many animals, such as migrating flocks of birds or shoals of fish. One theory states that group membership can improve navigational accuracy compared to limited or less accurate individual navigational ability in groups without leaders (“Many-wrongs principle”. Here, we simulate leaderless group navigation that includes social connections as preferential interactions between individuals. Our results suggest that underlying social networks can reduce navigational errors of groups and increase group cohesion. We use network summary statistics, in particular network motifs, to study which characteristics of networks lead to these improvements. It is networks in which preferences between individuals are not clustered, but spread evenly across the group that are advantageous in group navigation by effectively enhancing long-distance information exchange within groups. We suggest that our work predicts a base-line for the type of social structure we might expect to find in group-living animals that navigate without leaders [Current Zoology 58 (2: 329-341, 2012].
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Dundar, Halil; Brede, Dag A; La Rosa, Sabina Leanti; El-Gendy, Ahmed Osama; Diep, Dzung B; Nes, Ingolf F
2015-07-01
A novel antimicrobial peptide designated enterocin O16 was purified from Enterococcus faecalis. Mass spectrometry showed a monoisotopic mass of 7,231 Da, and N-terminal Edman degradation identified a 29-amino-acid sequence corresponding to residues 90 to 119 of the EF_1097 protein. Bioinformatic analysis showed that enterocin O16 is composed of the 68 most C-terminal residues of the EF_1097 protein. Introduction of an in-frame isogenic deletion in the ef1097 gene abolished the production of enterocin O16. Enterocin O16 has a narrow inhibitory spectrum, as it inhibits mostly lactobacilli. Apparently, E. faecalis is intrinsically resistant to the antimicrobial peptide, as no immunity connected to the production of enterocin O16 could be identified. ef1097 has previously been identified as one of three loci regulated by the fsr quorum-sensing system. The introduction of a nonsense mutation into fsrB consistently impaired enterocin O16 production, but externally added gelatinase biosynthesis-activating pheromone restored the antimicrobial activity. Functional genetic analysis showed that the EF_1097 proprotein is processed extracellularly into enterocin O16 by the metalloprotease GelE. Thus, it is evident that the fsr quorum-sensing system constitutes the regulatory unit that controls the expression of the EF_1097 precursor protein and the protease GelE and that the latter is required for the formation of enterocin O16. On the basis of these results, this study identified antibacterial antagonism as a novel aspect related to the function of fsr and provides a rationale for why ef1097 is part of the fsr regulon. The fsr quorum-sensing system modulates important physiological functions in E. faecalis via the activity of GelE. The present study presents a new facet of fsr signaling. The system controls the expression of three primary target operons (fsrABCD, gelE-sprE, and ef1097-ef1097b). We demonstrate that the concerted expression of these operons constitutes the
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Bonet, Bailey; Teufel, Robin; Crüsemann, Max; Ziemert, Nadine; Moore, Bradley S
2015-03-27
Heterologous expression of secondary metabolic pathways is a promising approach for the discovery and characterization of bioactive natural products. Herein we report the first heterologous expression of a natural product from the model marine actinomycete genus Salinispora. Using the recently developed method of yeast-mediated transformation-associated recombination for natural product gene clusters, we captured a type II polyketide synthase pathway from Salinispora pacifica with high homology to the enterocin pathway from Streptomyces maritimus and successfully produced enterocin in two different Streptomyces host strains. This result paves the way for the systematic interrogation of Salinispora's promising secondary metabolome.
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Kraiyot Saelim; Sireewan Kaewsuwan; Akio Tani; Suppasil Maneerat
2015-01-01
Enterocin CE5-1 produced by Enterococcus faecium CE5-1 isolated from the chicken gastrointestinal tract was active in the wide range of pH 2-10 and temperature 30-100°C and sensitive to proteolytic enzymes and -amylase. It remained active after storage at -20°C for 2 months. Moreover, enterocin CE5-1 showed antibacterial activity against lactobacilli, bacilli, listeria, staphylococci and enterococci, especially antibiotic-resistant enterococci. In vitro study of enterocin CE5-1 decr...
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Vandera, Elpiniki; Tsirka, Georgia; Kakouri, Athanasia; Koukkou, Anna-Irini; Samelis, John
2018-05-21
Enterococci are naturally selected for growth in thermized ewes'/goats' milk mixtures used for traditional cooked hard cheese processing in Greece. A culture-independent PCR-based approach was applied to detect the presence of enterocin-encoding genes in naturally culture-enriched thermized milk (TM). Portions of TM (63 °C, 30 s) collected from a commercial cheese plant before addition of starters were fermented at 37 °C for 48 h to facilitate growth of indigenous enterococci. The multiple enterocin-producing (m-Ent+) Enterococcus faecium KE82 and the nisin A-producing Lactococcus lactis subsp. cremoris M104 served as bacteriocin-positive inocula in separate TM treatments. The PCR results revealed a constant presence of the enterocin A, B and P genes in TM fermented naturally at 37 °C. Eleven out of 42 (26.2%) lactic isolates from the enriched TM cultures without inoculation were Ent+ E. faecium assigned to three biotypes. Biotype I (4 isolates) included single entA possessors, whereas biotype II (5 isolates) and biotype III (2 isolates) were m-Ent+ variants profiling entA-entB-entP and entA-entB genes, respectively. Biotype II displayed the strongest antilisterial activity in vitro. Surprisingly, 85.7% (6/7) of the m-Ent+ E. faecium were selectively isolated from Baird-Parker agar, reflecting their natural resistance to 0.01% tellurite contained in the egg yolk supplement. No cytolysin-positive E. faecalis or other Ent+ Enterococcus spp. were isolated. In conclusion, commercially thermized Greek milk is a natural pool or 'reservoir' of antagonistic Ent+ or m-Ent+ E. faecium strains that can be easily detected and recovered by applying this PCR-based approach to naturally fermented milks or cheese products. Copyright © 2018 Elsevier B.V. All rights reserved.
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Kumar, Manoj; Srivastava, Sheela
2011-06-01
Enterococci are well-known producers of antimicrobial peptides (enterocins) that possess potential as biopreservatives in food. In this study, divalent cations and release of intracellular potassium were used to assess the mechanism of interaction and killing of enterocin LR/6 produced by Enterococcus faecium LR/6 on three target Gram-positive and Gram-negative bacteria, namely Micrococcus luteus, Enterococcus sp. strain LR/3 and Escherichia coli K-12. Whilst treatment with enterocin LR/6 in all cases led to a significant loss of viability, suggesting a bactericidal mode of action, E. coli K-12 showed better tolerance than the other two strains. Bacteriocins have generally been reported to create pores in the membrane of sensitive cells and this function is diminished by divalent cations. In this study it was shown that Ca(2+) and Mg(2+) markedly improved the viability of enterocin LR/6-treated cells in a concentration-dependent manner. K(+) release as a sign of membrane leakiness was higher in M. luteus compared with the other two test strains. In agreement with the viability response, pre-exposure to Ca(2+) and Mg(2+) substantially reduced the amount of K(+) leakage by M. luteus and Enterococcus sp.; in the case of E. coli K-12, no leakage of K(+) was recorded. These results suggest that enterocin LR/6, which possesses good antibacterial potential, may not be very effective as a preservative in foods containing high concentrations of calcium and magnesium. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.
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Kaur, G; Singh, T P; Malik, R K
2013-01-01
Antilisterial efficiency of three bacteriocins, viz, Nisin, Pediocin 34 and Enterocin FH99 was tested individually and in combination against Listeria mononcytogenes ATCC 53135. A greater antibacterial effect was observed when the bacteriocins were combined in pairs, indicating that the use of more than one LAB bacteriocin in combination have a higher antibacterial action than when used individually. Variants of Listeria monocytogenes ATCC 53135 resistant to Nisin, Pediocin 34 and Enterocin FH99 were developed. Bacteriocin cross-resistance of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class. Resistance to Pediocin 34 conferred cross resistance to Enterocin FH 99 but not to Nisin. Similarly resistance to Enterocin FH99 conferred cross resistance to Pediocin 34 but not to Nisin. Also, the sensitivity of Nisin, Pediocin 34 and Enterocin FH99 resistant variants of Listeria monocytogenes to low pH, salt, sodium nitrite, and potassium sorbate was assayed in broth and compared to the parental wild-type strain. The Nisin, Pediocin 34 and Enterocin FH99 resistant variants did not have intrinsic resistance to low pH, sodium chloride, potassium sorbate, or sodium nitrite. In no case were the bacteriocin resistant Listeria monocytogenes variants examined were more resistant to inhibitors than the parental strains.
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Directory of Open Access Journals (Sweden)
G. Kaur
2013-01-01
Full Text Available Antilisterial efficiency of three bacteriocins, viz, Nisin, Pediocin 34 and Enterocin FH99 was tested individually and in combination against Listeria mononcytogenes ATCC 53135. A greater antibacterial effect was observed when the bacteriocins were combined in pairs, indicating that the use of more than one LAB bacteriocin in combination have a higher antibacterial action than when used individually. Variants of Listeria monocytogenes ATCC 53135 resistant to Nisin, Pediocin 34 and Enterocin FH99 were developed. Bacteriocin cross-resistance of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class. Resistance to Pediocin 34 conferred cross resistance to Enterocin FH 99 but not to Nisin. Similarly resistance to Enterocin FH99 conferred cross resistance to Pediocin 34 but not to Nisin. Also, the sensitivity of Nisin, Pediocin 34 and Enterocin FH99 resistant variants of Listeria monocytogenes to low pH, salt, sodium nitrite, and potassium sorbate was assayed in broth and compared to the parental wild-type strain. The Nisin, Pediocin 34 and Enterocin FH99 resistant variants did not have intrinsic resistance to low pH, sodium chloride, potassium sorbate, or sodium nitrite. In no case were the bacteriocin resistant Listeria monocytogenes variants examined were more resistant to inhibitors than the parental strains.
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Co-expression and characterization of enterocin CRL35 and its mutant in Escherichia coli Rosetta
Directory of Open Access Journals (Sweden)
Masías Emilse
2014-01-01
Full Text Available Even though many sequences and structures of bacteriocins from lactic acid bacteria have been fully characterized so far, little information is currently available about bacteriocins heterologously produced by Escherichia coli. For this purpose, the structural gene of enterocin CRL35, munA, was PCR-amplified using specific primers and cloned downstream of PelB sequence in the pET22b (+ expression vector. E. coli Rosetta (DE3 pLysS was chosen as the host for production and enterocin was purified by an easy two-step protocol. The bacteriocin was correctly expressed with the expected intramolecular disulfide bond. Nevertheless, it was found that a variant of the enterocin, differing by 12 Da from the native polypeptide, was co-expressed by E. coli Rosetta in comparable amount. Indeed, the mutant bacteriocin contained two amino acid substitutions that were characterized by matrix assisted laser desorption ionization-time of flight (MALDI-TOF and HPLCelectrospray (ESI-Q-TOF tandem mass spectrometry (MS/ MS sequencing. This is the first report regarding the production of mutants of pediocin-like bacteriocins in the E. coli expression system.
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Ramakrishnan, Vrinda; Narayan, Bhaskar; Halami, Prakash M
2012-08-01
Food borne diseases have a major impact on public health whose epidemiology is rapidly changing. The whole cells of pathogens involved or their toxins/metabolites affect the human health apart from spoiling sensory properties of the food products finally affecting the food industry as well as consumer health. With pathogens developing mechanisms of antibiotic resistance, there has been an increased need to replace antibiotics as well as chemical additives with naturally occurring bacteriocins. Bacteriocins are known to act mainly against Gram-positive pathogens and with little or no effect towards Gram-negative enteric bacteria. In the present study, combination effect of lipase and bacteriocin produced by Enterococcus faecium NCIM5363, a highly lipolytic lactic acid bacterium against various food pathogens was assessed. The lipase in combination with enterocin exhibited a lethal effect against Gram-negative pathogens. Scanning electron microscopy studies carried out to ascertain the constitutive mode of action of lipase and enterocin revealed that the lipase degrades the cell wall of Gram-negative bacteria and creates a pore through which enterocin enters thereby resulting in cell death. The novelty of this work is the fact that this is the first report revealing the synergistic effect of lipase with enterocin against Gram-negative bacteria.
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Hu, C-B; Zendo, T; Nakayama, J; Sonomoto, K
2008-09-01
To characterize the novel bacteriocin produced by Enterococcus durans. Enterococcus durans QU 49 was isolated from carrot and expressed bactericidal activity over 20-43 degrees C. Bacteriocins were purified to homogeneity using the three-step purification method, one of which, termed durancin TW-49M, was an enterocin B-homologous peptide with most identical residues occurring in the N-terminus. Durancin TW-49M was more tolerant in acidic than in alkali. DNA sequencing analysis revealed durancin TW-49M was translated as a prepeptide of the double-glycine type. Durancin TW-49M and enterocin B expressed similar antimicrobial spectra, in which no significant variation due to the diversity in their C-termini was observed. Durancin TW-49M, a novel nonpediocin-like class II bacteriocin, was characterized to the amino acid and genetic levels. The diverse C-terminal parts of durancin TW-49M and enterocin B were hardly to be suggested as the place determining the target cell specificity. This is the first and comprehensive study of a novel bacteriocin produced by Ent. durans. The high homology at the N-terminal halves between durancin TW-49M and enterocin B makes them suitable to study the structure-function relationship of bacteriocins and their immunity proteins.
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Maldonado-Barragán, Antonio; Caballero-Guerrero, Belén; Jiménez, Esther; Jiménez-Díaz, Rufino; Ruiz-Barba, José L; Rodríguez, Juan M
2009-07-31
Enterocin C (EntC), a class IIb bacteriocin was purified from culture supernatants of Enterococcus faecalis C901, a strain isolated from human colostrum. Enterocin C consists of two distinct peptides, named EntC1 and EntC2, whose complementary action is required for full antimicrobial activity. The structural genes entC1 and entC2 encoding enterocins EntC1 and EntC2, respectively, and that encoding the putative immunity protein (EntCI) are located in the 9-kb plasmid pEntC, harboured by E. faecalis C901. The N-terminal sequence of both antimicrobial peptides revealed that EntC1 (4284 Da) is identical to Ent1071A, one of the two peptides that form enterocin 1071 (Ent1071), a bacteriocin produced by E. faecalis BFE 1071. In contrast, EntC2 (3867 Da) presents the non-polar alanine residue at position 17 (Ala(17)) instead of the polar threonine residue (Thr(17)) in Ent1071B, the second peptide constituting Ent1071. In spite of peptide similarities, EntC differs from Ent1071 in major aspects, including the complementary activity among its constitutive peptides and its wider inhibitory spectrum of activity. Different amphiphilic alpha-helical conformations between EntC2 and Ent1071B could explain both, acquired complementary activity and increased antimicrobial spectrum.
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Barraza, Daniela E; Ríos Colombo, Natalia S; Galván, Adriana E; Acuña, Leonardo; Minahk, Carlos J; Bellomio, Augusto; Chalón, Miriam C
2017-09-01
The role of the class IIa bacteriocin membrane receptor protein remains unclear, and the following two different mechanisms have been proposed: the bacteriocin could interact with the receptor changing it to an open conformation or the receptor might act as an anchor allowing subsequent bacteriocin insertion and membrane disruption. Bacteriocin-producing cells synthesize an immunity protein that forms an inactive bacteriocin-receptor-immunity complex. To better understand the molecular mechanism of enterocin CRL35, the peptide was expressed as the suicidal probe EtpM-enterocin CRL35 in Escherichia coli, a naturally insensitive microorganism since it does not express the receptor. When the bacteriocin is anchored to the periplasmic face of the plasma membrane through the bitopic membrane protein, EtpM , E. coli cells depolarize and die. Moreover, co-expression of the immunity protein prevents the deleterious effect of EtpM-enterocin CRL35. The binding and anchoring of the bacteriocin to the membrane has demonstrated to be a sufficient condition for its membrane insertion. The final step of membrane disruption by EtpM-enterocin CRL35 is independent from the receptor, which means that the mannose PTS might not be involved in the pore structure. In addition, the immunity protein can protect even in the absence of the receptor. © 2017 John Wiley & Sons Ltd.
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Pérez Pulido, Rubén; Toledo, Julia; Grande, M José; Gálvez, Antonio; Lucas, Rosario
2015-03-02
In the present study, pulp obtained from cherimoya pulp (Annona cherimola) was inoculated with epiphytic microbiota collected from cherimoya fruits, and supplemented or not with the circular bacteriocin enterocin AS-48 (50μg/g) and then packed under vacuum. Samples supplemented or not with enterocin were treated by high hydrostatic pressure (600MPa, 8min) and then stored at 5°C for 30days. The single AS-48 treatment only delayed microbial growth non-significantly (p>0.05). HHP treatment reduced microbial counts by five log cycles, but it did not prevent further growth of survivors by day 7. The combined treatment (AS-48+HHP) was the most effective, keeping bacterial cell densities at ≤1.5 log CFU/g for up to 15days. 16S rRNA gene pyrosequencing analysis was done on amplicon libraries from the growth on TSA plates seeded with ten-fold dilutions of pulp suspensions and incubated at 22°C for 24h. The results obtained are limited by the experimental conditions used in the study, and only concern the bacterial fraction that was selected by the TSA and growth conditions used. Pantoea (Pantoea agglomerans, Pantoea vagans) were the operational taxonomic units (OTUs) detected at highest relative abundance in bacterial biomass grown from control samples for the first 7days of storage, followed by Enterococcus gallinarum and Leuconostoc mesenteroides during late storage. The single HHP treatment significantly reduced the relative abundance of OTUs belonging to Pantoea and strongly increased that of endosporeformers (mainly Bacillus firmus and Bacillus stratosphericus) early after treatment, although Pantoea became again the predominant OTUs during storage. Samples singly treated with enterocin AS-48 revealed a strong inhibition of E. gallinarum as well as an early decrease in the relative abundance of Pantoea and an increased relative abundance of OTUs belonging to other Gram-negative species (mainly from genera Serratia and Pseudomonas). The strong microbial
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Liu, Wenli; Zhang, Lanwei; Yi, Huaxi
2017-01-01
The macro- and micronutrients in traditional medium, such as MRS, used for cultivating lactic acid bacteria, especially for bacteriocin production, have not been defined, preventing the quantitative monitoring of metabolic flux during bacteriocin biosynthesis. To enhance Enterocin Y31 production and simplify steps of separation and purification, we developed a simplified chemically defined medium (SDM) for the growth of Enterococcus faecium Y31 and production of its bacteriocin, Enterocin Y31...
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Avcı, Mine; Özden Tuncer, Banu
2017-07-06
The purpose of this study was to determine the antimicrobial activity and occurrence of bacteriocin structural genes in Enterococcus spp. isolated from different cheeses and also investigate some of their virulence factors. Enterococcus strains were isolated from 33 different cheeses. Enterococcus faecium (6 strains) and Enterococcus faecalis (5 strains) enterocin-producing strains were identified by 16S rDNA analyses. Structural genes entA, entB, entP and entX were detected in some isolates. Multiple enterocin structural genes were found in 7 strains. None of the tested enterococci demonstrated anyβ-haemolytic activity and only one strain had gelatinase activity. Six strains showed multiple antibiotic resistance patterns and in addition, vanA and several virulence genes were detected in many strains. Only E. faecalis MBE1-9 showed tyrosine decarboxylase activity and tdc gene was detected only in this strain.
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Xiang, Longkuan; Kalaitzis, John A.; Moore, Bradley S.
2004-01-01
The bacteriostatic natural product enterocin from the marine microbe “Streptomyces maritimus” has an unprecedented carbon skeleton that is derived from an aromatic polyketide biosynthetic pathway. Its caged tricyclic, nonaromatic core is derived from a linear poly-β-ketide precursor that formally undergoes a Favorskii-like oxidative rearrangement. In vivo characterization of the gene encM through mutagenesis and heterologous biosynthesis demonstrated that its protein product not only is solely responsible for the oxidative C—C rearrangement, but also facilitates two aldol condensations plus two heterocycle forming reactions. In total, at least five chiral centers and four rings are generated by this multifaceted flavoprotein. Heterologous expression of the enterocin biosynthesis genes encABCDLMN in Streptomyces lividans resulted in the formation of the rearranged metabolite desmethyl-5-deoxyenterocin and the shunt products wailupemycins D-G. Addition of the methyltransferase gene encK, which was previously proposed through mutagenesis to additionally assist EncM in the Favorskii rearrangement, shifted the production to the O-methyl derivative 5-deoxyenterocin. The O-methyltransferase EncK seems to be specific for the pyrone ring of enterocin, because bicyclic polyketides bearing pyrone rings are not methylated in vivo. Expression of encM with different combinations of homologous actinorhodin biosynthesis genes did not result in the production of oxidatively rearranged enterocin-actinorhodin hybrid compounds as anticipated, suggesting that wild-type EncM may be specific for its endogenous type II polyketide synthase or for benzoyl-primed polyketide precursors. PMID:15505225
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Iseppi, Ramona; Pilati, Francesco; Marini, Michele; Toselli, Maurizio; de Niederhäusern, Simona; Guerrieri, Elisa; Messi, Patrizia; Sabia, Carla; Manicardi, Giuliano; Anacarso, Immacolata; Bondi, Moreno
2008-04-30
In this study, Enterocin 416K1, a bacteriocin produced by Enterococcus casseliflavus IM 416K1, was entrapped in an organic-inorganic hybrid coating applied to a LDPE (low-density polyethylene) film for its potential use in the active food packaging field. The antibacterial activity of the coated film was evaluated against Listeria monocytogenes NCTC 10888 by qualitative modified agar diffusion assay, quantitative determination in listeria saline solution suspension and direct contact with artificially contaminated food samples (frankfurters and fresh cheeses) stored at room and refrigeration temperatures. All investigations demonstrated that enterocin-activated coatings have a good anti-listeria activity. Qualitative tests showed a clear zone of inhibition in the indicator lawn in contact with and around the coated film. During the quantitative antibacterial evaluation the L. monocytogenes viable counts decreased to 1.5 log units compared to the control. The inhibitory capability was confirmed also in food-contact assays. In all food samples packed with coated films we observed a significant decrease in L. monocytogenes viable counts in the first 24 h compared to the control. This difference was generally maintained up to the seventh day and then decreased, with the exception of the cheese samples stored at refrigeration temperature.
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Achemchem, F; Martínez-Bueno, M; Abrini, J; Valdivia, E; Maqueda, M
2005-01-01
Characterization of Ent F-58 produced by Enterococcus faecium strain F58 isolated from Jben, a soft, farmhouse goat's cheese manufactured without starter cultures. E. faecium strain F58 was isolated because of its broad inhibitory spectrum, including activity against food-borne pathogenic and spoilage bacteria. The antimicrobial substance was produced during the growth phase, with maximum production after 16-20 h of incubation at 30 degrees C, and was stable over a wide pH range (4-8) and at high temperatures (5 min at 100 degrees C). The enterocin was purified to homogeneity using cation exchange and hydrophobic interaction on C-18 and reverse-phase high-performance liquid chromatography. The activity was eluted as two individual active fractions (F-58A and F-58B) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis showed masses of 5210.5 and 5234.3 Da respectively. Both peptides were partially sequenced by Edman degradation, and amino-acid sequencing revealed high similarity with enterocin L50 (I). PCR-amplified fragments containing the structural genes for F-58 A and B were located in a 22-kb plasmid harboured by this strain. We verified that it also holds the structural gene for P-like enterocin. E. faecium strain F58 from Jben cheese, a producer of enterocin L50, exerts an inhibitory effect against strains of genera such as Listeria, Staphylococcus, Clostridium, Brochothrix and Bacillus. Enterocin was characterized according to its functional and biological properties, purification to homogeneity and an analysis of its amino acid and genetic sequences. E. faecium strain F58 is a newly discovered producer of enterocin L50, the biotechnological characteristics of which indicate its potential for application as a protective agent against pathogens and spoilage bacteria in foods.
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Saavedra, Lucila; Minahk, Carlos; de Ruiz Holgado, Aída P.; Sesma, Fernando
2004-01-01
The enterocin CRL35 biosynthetic gene cluster was cloned and sequenced. The sequence was revealed to be highly identical to that of the mundticin KS gene cluster (S. Kawamoto, J. Shima, R. Sato, T. Eguchi, S. Ohmomo, J. Shibato, N. Horikoshi, K. Takeshita, and T. Sameshima, Appl. Environ. Microbiol. 68:3830-3840, 2002). Short synthetic peptides were designed based on the bacteriocin sequence and were evaluated in antimicrobial competitive assays. The peptide KYYGNGVSCNKKGCS produced an enhancement of enterocin CRL35 antimicrobial activity in a buffer system. PMID:15215149
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Gupta, H; Malik, R K; Bhardwaj, A; Kaur, G; De, S; Kaushik, J K
2010-06-01
Enterococcus faecium FH 99 was isolated from human faeces and selected because of its broad spectrum of inhibitory activity against several Gram-positive foodborne spoilage and pathogenic bacteria. Ent. faecium FH 99 accumulates enterocin in large number in early stationary phase of the growth. The enterocin FH 99 was stable over a wide pH range (2-10) and recovered activity even after treatment at high temperatures (10 min at 100°C). The enterocin was subjected to different purification techniques viz., gel filteration, cation exchange chromatography and reverse-phase high-performance liquid chromatography. The activity was eluted as one individual active fraction. SDSPAGE revealed a molecular weight of less than 6.5 kDa. Studies carried out to identify the genetic determinants for bacteriocin production showed that this trait may be plasmid encoded as loss in both of the plasmids (size>chromosomal DNA) led to loss in bacteriocin production by Ent. faecium FH 99. Ent. faecium strain FH 99 is a newly discovered high bacteriocin producer with Activity Units 1.8 × 10(5) AU ml(-1) and its characteristics indicate that it may have strong potential for application as a protective agent against pathogens and spoilage bacteria in foods.
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Satish Kumar, R; Kanmani, P; Yuvaraj, N; Paari, K A; Pattukumar, V; Arul, V
2011-12-01
A bacteriocin producer strain MC13 was isolated from the gut of Mugil cephalus (grey mullet) and identified as Enterococcus faecium. The bacteriocin of E. faecium MC13 was purified to homogeneity, as confirmed by Tricine sodium dodecyl sulphate - polyacrylamide gel electrophoresis (SDS-PAGE). Reverse-phase high-performance liquid chromatography (HPLC) analysis showed a single active fraction eluted at 26 min, and matrix-assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry analysis showed the molecular mass to be 2.148 kDa. The clear zone in native PAGE corresponding to enterocin MC13 band further substantiated its molecular mass. A dialyzed sample (semicrude preparation) of enterocin MC13 was broad spectrum in its action and inhibited important seafood-borne pathogens: Listeria monocytogenes , Vibrio parahaemolyticus, and Vibrio vulnificus. This antibacterial substance was sensitive to proteolytic enzymes: trypsin, protease, and chymotrypsin but insensitive to catalase and lipase, confirming that inhibition was due to the proteinaceous molecule, i.e., bacteriocin, and not due to hydrogen peroxide. Enterocin MC13 tolerated heat treatment (up to 90 °C for 20 min). Enterococcus faecium MC13 was effective in bile salt tolerance, acid tolerance, and adhesion to the HT-29 cell line. These properties reveal the potential of E. faecium MC13 to be a probiotic bacterium. Enterococcus faecium MC13 could be used as potential fish probiotic against pathogens such as V. parahaemolyticus, Vibrio harveyi, and Aeromonas hydrophila in fisheries. Also, this could be a valuable seafood biopreservative against L. monocytogenes.
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Lucas, R; Grande, M A J; Abriouel, H; Maqueda, M; Ben Omar, N; Valdivia, E; Martínez-Cañamero, M; Gálvez, A
2006-10-01
The enterococcal bacteriocin (enterocin) AS-48 is a broad-spectrum cyclic peptide. Enterocin AS-48 was tested against Bacillus coagulans in three vegetable canned foods: tomato paste (pH 4.64), syrup from canned peaches (pH 3.97), and juice from canned pineapple (pH 3.65). When vegetative cells of B. coagulans CECT (Spanish Type Culture Collection) 12 were inoculated in tomato paste supplemented with 6 microg/ml AS-48 and stored at different temperatures, viable cell counts were reduced by approximately 2.37 (4 degrees C), 4.3 (22 degrees C) and 3.0 (37 degrees C) log units within 24 h storage. After 15-days storage, no viable cells were detected in any sample. Strain B. coagulans CECT 561 showed a poor survival in tomato paste, but surviving cells were also killed by AS-48. The bacteriocin was also very active against B. coagulans CECT 12 vegetative cells in juice from canned pineapple stored at 22 degrees C, and slightly less active in syrup from canned peaches. In food samples supplemented with 1.5% lactic acid, enterocin AS-48 (6 microg/ml) rapidly reduced viable counts of vegetative cells below detection limits within 24 h storage. Addition of glucose and sucrose (10% and 20%) significantly increased bacteriocin activity against vegetative cells of B. coagulans CECT 12. Enterocin AS-48 had no significant effect on B. coagulans CECT 12 spores. However, the combined application of AS-48 and heat (80-95 degrees C for 5 min) significantly increased the effect of thermal treatments on spores.
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Xiang, Longkuan; Moore, Bradley S.
2003-01-01
The novel benzoyl coenzyme A (benzoyl-CoA) biosynthesis pathway in “Streptomyces maritimus” was investigated through a series of target-directed mutations. Genes involved in benzoyl-CoA formation were disrupted through single-crossover homologous recombination, and the resulting mutants were analyzed for their ability to biosynthesize the benzoyl-CoA-primed polyketide antibiotic enterocin. Inactivation of the unique phenylalanine ammonia-lyase-encoding gene encP was previously shown to be absolutely required for benzoyl-CoA formation in “S. maritimus”. The fatty acid β-oxidation-related genes encH, -I, and -J, on the other hand, are necessary but not required. In each case, the yield of benzoyl-CoA-primed enterocin dropped below wild-type levels. We attribute the reduced benzoyl-CoA formation in these specific mutants to functional substitution and cross-talk between the products of genes encH, -I, and -J and the enzyme homologues of primary metabolism. Disruption of the benzoate-CoA ligase encN gene did not perturb enterocin production, however, demonstrating that encN is extraneous and that benzoic acid is not a pathway intermediate. EncN rather serves as a substitute pathway for utilizing exogenous benzoic acid. These experiments provide further support that benzoyl-CoA is formed in a novel bacterial pathway that resembles the eukaryotic assembly of benzoyl-CoA from phenylalanine via a β-oxidative path. PMID:12511484
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Martínez Viedma, Pilar; Sobrino López, Angel; Ben Omar, Nabil; Abriouel, Hikmate; Lucas López, Rosario; Valdivia, Eva; Martín Belloso, Olga; Gálvez, Antonio
2008-12-10
The effect of the broad spectrum cyclic antimicrobial peptide enterocin AS-48 combination with high-intensity pulsed-electric field (HIPEF) treatment (35 kV/cm, 150 Hz, 4 micros and bipolar mode) was tested on Salmonella enterica CECT 915 in apple juice. A response surface methodology was applied to study the bactericidal effects of the combined treatment. The process variables were AS-48 concentration, temperature, and HIPEF treatment time. While treatment with enterocin AS-48 alone up to 60 microg/ml had no effect on the viability of S. enterica in apple juice, an increased bactericidal activity was observed in combination with HIPEF treatments. Survival fraction was affected by treatment time, enterocin AS48 concentration and treatment temperature. The combination of 100 micros of HIPEF treatment, 30 microg/ml of AS-48, and temperature of 20 degrees C resulted in the lowest inactivation, with only a 1.2-log reduction. The maximum inactivation of 4.5-log cycles was achieved with HIPEF treatment for 1000 micros in combination with 60 microg/ml of AS-48 and a treatment temperature of 40 degrees C. Synergism between enterocin AS-48 and HIPEF treatment depended on the sequence order application, since it was observed only when HIPEF was applied in the presence of previously-added bacteriocin. The combined treatment could improve the safety of freshly-made apple juice against S. enterica transmission.
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Lauková, Andrea; Simonová, Monika Pogány; Chrastinová, Ľubica; Plachá, Iveta; Čobanová, Klaudia; Formelová, Zuzana; Chrenková, Mária; Ondruška, Ľubomír; Strompfová, Viola
2016-03-01
This study presents the effects of the probiotic and enterocin M-producing strain Enterococcus faecium AL41 on microbiota, phagocytic activity (PA), oxidative stress, performance and biochemical parameters when applied individually or in combination with Eleutherococcus senticosus in rabbits. The novelty of the study lies in the use of our non-rabbit-derived strain (AL41 = CCM8558) which produces new enterocin M. Ninety-six post-weaned rabbits (Hyplus breed) aged 5 weeks were divided into three experimental groups, 24 in each: E. senticosus (ES, 30 g/100 kg) in feed, E. faecium AL41 (10(9) CFU/mL marked by rifampicin to differentiate it from other enterococci) in water, and ES + AL. AL41 colonized sufficiently in rabbits to reduce coliforms, staphylococci, pseudomonads and clostridia. Slight decrease in bacteria was also found in the caecum and appendix. Phagocytic activity was significantly increased in the experimental groups compared to the control group (CG) (p < 0.001; p < 0.05). Applications did not evoke oxidative stress. Biochemical parameters in blood and caecal organic acids were slightly influenced. Average daily weight gain was slightly higher in ES and AL + ES. Combinative application of E. faecium with E. senticosus can be beneficial in rabbits. AL41 strain alone and in combination with ES produced reduction in spoilage bacteria; the highest stimulation of PA was in the AL41 + ES group.
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Hu, Chih-Bo; Malaphan, Wanna; Zendo, Takeshi; Nakayama, Jiro; Sonomoto, Kenji
2010-07-01
Enterocin X, composed of two antibacterial peptides (Xalpha and Xbeta), is a novel class IIb bacteriocin from Enterococcus faecium KU-B5. When combined, Xalpha and Xbeta display variably enhanced or reduced antibacterial activity toward a panel of indicators compared to each peptide individually. In E. faecium strains that produce enterocins A and B, such as KU-B5, only one additional bacteriocin had previously been known.
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Rehaiem, A; Martínez, B; Manai, M; Rodríguez, A
2010-05-01
Characterization and purification of a bacteriocin produced by a wild Enterococcus faecium strain, isolated from a Tunisian traditional fermented milk. Enterococcus faecium MMRA was selected on the basis of its strong anti-Listeria activity. The antibacterial activity was sensitive to proteases, confirming its proteinaceous nature. It was extremely heat stable (15 min at 121 degrees C), remained active over a wide pH range (2-12), and also after treatment with lipase, amylase, organic solvents, detergents, lyophilisation and long-term storage at -20 degrees C. Production of the bacteriocin occurred throughout the logarithmic growth phase, it did not adhere to the surface of the producer cells and the mode of action was bactericidal. After partial purification of the active supernatants, a 4-kDa band with antibacterial activity was revealed by SDS-PAGE electrophoresis and bioassay. Tryptic digestion followed by MALDI-TOF mass spectrometry identified the peptide as enterocin A. The inhibitory activity of Ent. faecium MMRA, a wild strain isolated from the artisan dairy beverage 'Rayeb', is due to the synthesis of an enterocin A. Traditional fresh Tunisian fermented dairy products are generally manufactured with raw milk that can be used as a source of uncharacterized wild lactic acid bacteria strains. To our knowledge, this is the first report on the isolation of an enterocin A producing Ent. faecium from 'Rayeb'. This bacteriocin or the producing strain might have a promising potential in biopreservation to enhance the hygienic quality of this dairy product.
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Hu, Chih-Bo; Malaphan, Wanna; Zendo, Takeshi; Nakayama, Jiro; Sonomoto, Kenji
2010-01-01
Enterocin X, composed of two antibacterial peptides (Xα and Xβ), is a novel class IIb bacteriocin from Enterococcus faecium KU-B5. When combined, Xα and Xβ display variably enhanced or reduced antibacterial activity toward a panel of indicators compared to each peptide individually. In E. faecium strains that produce enterocins A and B, such as KU-B5, only one additional bacteriocin had previously been known. PMID:20418437
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Rizzo, Antonio; Trauner, Dirk
2018-04-06
An approach toward (-)-enterocin, an antibiotic isolated from Streptomyces hygroscopicus, is described. Its compact, heavily oxidized protoadamantane core represents a daunting challenge for an efficient synthesis. Convergent assembly of its 2-oxabicyclo[3.3.1]nonane core with a cuprate-mediated Barbier reaction is disclosed. Its functionalization to a suitable substrate for a biomimetic aldol to close the final ring of the natural product is evaluated.
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Waldman, David A; Atwater, Leanne E; Davidson, Ronald A
2004-02-01
Personality has seen a resurgence in the work performance literature. The Five-Factor Model (FFM) represents a set of personality factors that has received the most attention in recent years. Despite its popularity, the FFM may not be sufficiently comprehensive to account for relevant variation across performance dimensions or tasks. Accordingly, the present study also considers how individualism may predict additional variance in performance beyond the FFM. The study involved 152 undergraduate students who experienced a leaderless group discussion (LGD) exercise. Results showed that while the FFM accounted for variance in students' LGD performance, individualism (independence) accounted for additional, unique variance. Furthermore, analyses of the group compositions revealed curvilinear relationships between the relative amount of extraversion, conscientiousness, and individualism in relation to group-level performance.
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Dundar, Halil; Brede, Dag A.; La Rosa, Sabina Leanti; El-Gendy, Ahmed Osama; Diep, Dzung B.; Nes, Ingolf F.
2015-01-01
A novel antimicrobial peptide designated enterocin O16 was purified from Enterococcus faecalis. Mass spectrometry showed a monoisotopic mass of 7,231 Da, and N-terminal Edman degradation identified a 29-amino-acid sequence corresponding to residues 90 to 119 of the EF_1097 protein. Bioinformatic analysis showed that enterocin O16 is composed of the 68 most C-terminal residues of the EF_1097 protein. Introduction of an in-frame isogenic deletion in the ef1097 gene abolished the production of e...
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Viedma, Pilar Martínez; Abriouel, Hikmate; Ben Omar, Nabil; López, Rosario Lucas; Valdivia, Eva; Gálvez, Antonio
2009-05-01
The cyclic bacteriocin enterocin AS-48 was tested on a cocktail of two Geobacillus stearothermophilus strains in canned food samples (corn and peas), and in coconut milk. AS-48 (7 microg/g) reduced viable cell counts below detection levels in samples from canned corn and peas stored at 45 degrees C for 30 days. In coconut milk, bacterial inactivation by AS-48 (1.75 microg/ml) was even faster. In all canned food and drink samples inoculated with intact G. stearothermophilus endospores, bacteriocin addition (1.75 microg per g or ml of food sample) rapidly reduced viable cell counts below detection levels and avoided regrowth during storage. After a short-time bacteriocin treatment of endospores, trypsin addition markedly increased G. stearothermophilus survival, supporting the effect of residual bacteriocin on the observed loss of viability for endospores. Results from this study support the potential of enterocin AS-48 as a biopreservative against G. stearothermophilus.
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Borrero, Juan; Jiménez, Juan J; Gútiez, Loreto; Herranz, Carmen; Cintas, Luis M; Hernández, Pablo E
2011-10-20
Replacement of the leader sequence (LS) of the bacteriocin enterocin A (LS(entA)) by the signal peptides (SP) of the protein Usp45 (SP(usp45)), and the bacteriocins enterocin P (SP(entP)), and hiracin JM79 (SP(hirJM79)) permits the production, secretion, and functional expression of EntA by different lactic acid bacteria (LAB). Chimeric genes encoding the SP(usp45), the SP(entP), and the SP(hirJM79) fused to mature EntA plus the EntA immunity genes (entA+entiA) were cloned into the expression vectors pNZ8048 and pMSP3545, under control of the inducible P(nisA) promoter, and in pMG36c, under control of the constitutive P(32) promoter. The amount, antimicrobial activity, and specific antimicrobial activity of the EntA produced by the recombinant Lactococcus lactis, Enterococcus faecium, E. faecalis, Lactobacillus sakei and Pediococcus acidilactici hosts varied depending on the signal peptide, the expression vector, and the host strain. However, the antimicrobial activity and the specific antimicrobial activity of the EntA produced by most of the LAB transformants was lower than expected from their production. The supernatants of the recombinant L. lactis NZ9000 (pNZUAI) and L. lactis NZ9000 (pNZHAI), overproducers of EntA, showed a 1.2- to 5.1-fold higher antimicrobial activity than that of the natural producer E. faecium T136 against different Listeria spp. Copyright © 2011 Elsevier B.V. All rights reserved.
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Ishibashi, Naoki; Himeno, Kohei; Masuda, Yoshimitsu; Perez, Rodney Honrada; Iwatani, Shun; Wilaipun, Pongtep; Leelawatcharamas, Vichien; Nakayama, Jiro; Sonomoto, Kenji
2014-01-01
Enterococcus faecium NKR-5-3, isolated from Thai fermented fish, is characterized by the unique ability to produce five bacteriocins, namely, enterocins NKR-5-3A, -B, -C, -D, and -Z (Ent53A, Ent53B, Ent53C, Ent53D, and Ent53Z). Genetic analysis with a genome library revealed that the bacteriocin structural genes (enkA [ent53A], enkC [ent53C], enkD [ent53D], and enkZ [ent53Z]) that encode these peptides (except for Ent53B) are located in close proximity to each other. This NKR-5-3ACDZ (Ent53ACDZ) enterocin gene cluster (approximately 13 kb long) includes certain bacteriocin biosynthetic genes such as an ABC transporter gene (enkT), two immunity genes (enkIaz and enkIc), a response regulator (enkR), and a histidine protein kinase (enkK). Heterologous-expression studies of enkT and ΔenkT mutant strains showed that enkT is responsible for the secretion of Ent53A, Ent53C, Ent53D, and Ent53Z, suggesting that EnkT is a wide-range ABC transporter that contributes to the effective production of these bacteriocins. In addition, EnkIaz and EnkIc were found to confer self-immunity to the respective bacteriocins. Furthermore, bacteriocin induction assays performed with the ΔenkRK mutant strain showed that EnkR and EnkK are regulatory proteins responsible for bacteriocin production and that, together with Ent53D, they constitute a three-component regulatory system. Thus, the Ent53ACDZ gene cluster is essential for the biosynthesis and regulation of NKR-5-3 enterocins, and this is, to our knowledge, the first report that demonstrates the secretion of multiple bacteriocins by an ABC transporter. PMID:25149515
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Dezwaan, Diane C.; Mequio, Michael J.; Littell, Julia S.; Allen, Jonathan P.; Rossbach, Silvia; Pybus, Vivien
2009-01-01
A bacteriocin produced by a vaginal isolate of Enterococcus faecium strain 62-6, designated enterocin 62-6, was characterized following purification and DNA sequence analysis and compared to previously described bacteriocins. Enterocin 62-6 was isolated from brain heart infusion (BHI) culture supernatants using ammonium sulfate precipitation followed by elution from a Sepharose cation exchange column using a continuous salt gradient (0.1–0.7 M NaCl). SDS-PAGE of an active column fraction resulted in an electrophoretically pure protein, which corresponded to the growth inhibition of the sensitive Lactobacillus indicator strain in the gel overlay assay. Purified enterocin 62-6 was shown to be heat- and pH-stable, and sensitive to the proteolytic enzymes α-chymotrypsin and pepsin. Results from mass spectrometry suggested that it comprised two peptides of 5206 and 5219±1 Da, which was confirmed by DNA sequence analysis. The characteristics of enterocin 62-6 as a small, heat- and pH-stable, cationic, hydrophobic, two-peptide, plasmid-borne bacteriocin, with an inhibitory spectrum against a broad range of Gram-positive but not Gram-negative bacteria, were consistent with its classification as a class IIc bacteriocin. Furthermore, its wide spectrum of growth inhibitory activity against Gram-positive bacteria of vaginal origin including lactobacilli, and stability under the acidic conditions of the vagina, are consistent with our hypothesis that it could have potential significance in disrupting the ecology of the vaginal tract and pave the way for the establishment of the abnormal microbiota associated with the vaginal syndrome bacterial vaginosis. This is the first class IIc bacteriocin produced by a strain of E. faecium of vaginal origin to be characterized. PMID:19578555
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Nagar, Rupa; Rao, Alka
2017-05-12
Glycosyltransferases are essential tools for in vitro-glycoengineering. Bacteria harbor an unexplored variety of protein glycosyltransferases. Here, we describe a peptide glycosyltransferase (EntS) encoded by ORF0417 of Enterococcus faecalis TX0104. EntS di-glycosylates linear peptide of enterocin 96- a known antibacterial, in vitro. It is capable of transferring as well as extending the glycan onto the peptide in an iterative sequential dissociative manner. It can catalyze multiple linkages: Glc/Gal(-O)Ser/Thr, Glc/Gal(-S)Cys and Glc/Gal(β)Glc/Gal(-O/S)Ser/Thr/Cys, in one pot. Using EntS generated glycovariants of enterocin 96 peptide, size and identity of the glycan are found to influence bioactivity of the peptide. The study identifies EntS as an enzyme worth pursuing, for in vitro peptide glycoengineering. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
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Batdorj, B; Dalgalarrondo, M; Choiset, Y; Pedroche, J; Métro, F; Prévost, H; Chobert, J-M; Haertlé, T
2006-10-01
The aim of this study was to isolate and identify bacteriocin-producing lactic acid bacteria (LAB) issued from Mongolian airag (traditional fermented mare's milk), and to purify and characterize bacteriocins produced by these LAB. Identification of the bacteria (Enterococcus durans) was carried out on the basis of its morphological, biochemical characteristics and carbohydrate fermentation profile and by API50CH kit and 16S rDNA analyses. The pH-neutral cell-free supernatant of this bacterium inhibited the growth of several Lactobacillus spp. and food-borne pathogens including Escherichia coli, Staphylococcus aureus and Listeria innocua. The antimicrobial agent (enterocin A5-11) was heat stable and was not sensitive to acid and alkaline conditions (pH 2-10), but was sensitive to several proteolytic enzymes. Its inhibitory activity was completely eliminated after treatment with proteinase K and alpha-chymotrypsin. The activity was however not completely inactivated by other proteases including trypsin and pepsin. Three-step purification procedure with high recovery yields was developed to separate two bacteriocins. The applied procedure allowed the recovery of 16% and 64% of enterocins A5-11A and A5-11B, respectively, present in the culture supernatant with purity higher than 99%. SDS-PAGE analyses revealed that enterocin A5-11 has a molecular mass of 5000 Da and mass spectrometry analyses demonstrates molecular masses of 5206 and 5218 Da for fractions A and B, respectively. Amino acid analyses of both enterocins indicated significant quantitative difference in their contents in threonine, alanine, isoleucine and leucine. Their N-termini were blocked hampering straightforward Edman degradation. Bacteriocins A5-11A and B from Ent. durans belong to the class II of bacteriocins. Judging from molecular masses, amino acid composition and spectrum of activities, bacteriocins A5-11A and B from Ent. durans show high degree of similarity with enterocins L50A and L50B
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Assay of enterocin AS-48 for inhibition of foodborne pathogens in desserts.
Martinez Viedma, Pilar; Abriouel, Hikmate; Ben Omar, Nabil; Lucas López, Rosario; Valdivia, Eva; Gálvez, Antonio
2009-08-01
Enterocin AS-48 was tested against Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes in different kinds of desserts. The highest activity against S. aureus was detected in baker cream. However, in yogurt-type soy-based desserts and in gelatin pudding, AS-48 (175 arbitrary units [AU]/g) reduced viable cell counts of S. aureus by only 1.5 to 1.8 log units at most. The efficacy of AS-48 in puddings greatly depended on inoculum size, and viable S. aureus counts decreased below detection levels within 24 h for inocula lower than 4 to 5.5 log CFU/g. For L. monocytogenes, bacteriocin concentrations of 52.5 to 87.5 AU/g reduced viable counts below detection levels and avoided regrowth of survivors. The lowest activity was detected in yogurt-type desserts. For B. cereus, viable cell counts were reduced below detection levels for bacteriocin concentrations of 52.5 AU/g in instant pudding without soy or by 175 AU/g in the soy pudding. In gelatin pudding, AS-48 (175 AU/g) reduced viable cell counts of B. cereus below detection levels after 8 h at 10 degrees C or after 48 h at 22 degrees C. Bacteriocin addition also inhibited gelatin liquefaction caused by the proteolytic activity of B. cereus.
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Masias, Emilse; Sanches, Paulo R S; Dupuy, Fernando G; Acuna, Leonardo; Bellomio, Augusto; Cilli, Eduardo; Saavedra, Lucila; Minahk, Carlos
2015-01-01
Two shorter peptides derived from enterocin CRL35, a 43-mer bacteriocin, were synthesized i.e. the N-terminal fragment spanning from residues 1 to 15, and a 28-mer fragment that represents the C-terminal of enterocin CRL35, the residues 16 to 43. The separate peptides showed no activity when combined. On one hand, the 28-mer peptide displayed an unpredicted antimicrobial activity. On the other, 15- mer peptide had no consistent anti-Listeria effect. The dissociation constants calculated from experimental data indicated that all peptides could bind at similar extent to the sensitive cells. However, transmembrane electrical potential was not dissipated to the same level by the different peptides; whereas the full-length and the C-terminal 28-mer fragment induced almost full dissipation, 15-mer fragment produced only a slow and incomplete effect. Furthermore, a different interaction of each peptide with membranes was demonstrated based on studies carried out with liposomes, which led us to conclude that activity was related to structure rather than to net positive charges. These results open up the possibility of designing new peptides based on the 28-mer fragment with enhanced activity, which would represent a promising approach for combating Listeria and other pathogens.
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Meniscal tissue regeneration in porous 50/50 copoly(L-lactide/epsilon-caprolactone) implants
de Groot, J. H.; Zijlstra, F. M.; Kuipers, HW; Pennings, A. J.; Veth, RPH; Jansen, HWB
Porous materials of a high-molecular-weight 50/50 copolymer of L-lactide and epsilon-caprolactone with different compression moduli were used for meniscal repair. In contrast to the previously used 4,4'-diphenylmethane and 1,6-trans-cyclohexane diisocyanates containing polyurethanes, degradation
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Gutierrez, Jorge; Larsen, Rasmus; Cintas, Luis M.; Kok, Jan; Hernandez, Pablo E.
Enterocin P (EntP), a sec-dependent bacteriocin from Enterococcus faecium P13, was produced by Lactococcus lactis. The EntP structural gene (entP) with or without the EntP immunity gene (entiP) was cloned in (1), plasmid pMG36c under control of the lactococcal constitutive promoter P-32, (2) in
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Escamilla-Martínez, E E; Cisneros, Y M Álvarez; Fernández, F J; Quirasco-Baruch, M; Ponce-Alquicira, E
2017-10-09
The Enterococcus faecium strain MXVK29, isolated from fermented sausages, produces a bacteriocin with a molecular mass of 3.5 kDa that belongs to the class of enterocins II.1, according to the terminal amino acid sequence, and has been identified as enterocin A. This bacteriocin is active against selected strains of Listeria, Staphylococcus, Pediococcus, and Enterococcus. In this study, we identified the genes adjacent to the structural gene for this bacteriocin, such as the immunity gene (entI) and the inducer gene (entF). Accessory genes for this bacteriocin, such as entK, entR, and entT, were identified as well, in addition to the orf2 and orf3, showing a high identity with class IIb peptides bacteriocins. The orf2 shows the consensus motif GxxxG, similar to those shown by bacteriocins such as PlnNC8α, EntCα, and Ent1071A, whereas orf3 shows a consensus motif SxxxS similar to that present in PlnNC8β (AxxxA). PlnNC8 is expressed only in bacterial cocultures, so there is the possibility that the expression of this two-peptide bacteriocin can be induced by a similar mechanism. So far, only the expression of enterocin A has been found in this strain; however, the presence of the genes ent29α and ent29β opens the possibility for further research on its induction, functionality, and origin. Although there are reports on this type of bacteriocin (EntX, EntC, and Ent1071) in other strains of E. faecium, no report exists yet on an Enterococcus strain producing two different classes of bacteriocin.
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Enterocin T, a novel class IIa bacteriocin produced by Enterococcus sp. 812.
Chen, Yi-Sheng; Yu, Chi-Rong; Ji, Si-Hua; Liou, Min-Shiuan; Leong, Kun-Hon; Pan, Shwu-Fen; Wu, Hui-Chung; Lin, Yu-Hsuan; Yu, Bi; Yanagida, Fujitoshi
2013-09-01
Enterococcus sp. 812, isolated from fresh broccoli, was previously found to produce a bacteriocin active against a number of Gram-positive bacteria, including Listeria monocytogenes. Bacteriocin activity decreased slightly after autoclaving (121 °C for 15 min), but was inactivated by protease K. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 4,521.34 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2-ATYYGNGVYXDKKKXWVEWGQA, by Edman degradation, which contained the consensus class IIa bacteriocin motif YGNGV in the N-terminal region. The obtained partial sequence showed high homology with some enterococcal bacteriocins; however, no identical peptide or protein was found. This peptide was therefore considered to be a novel bacteriocin produced by Enterococcus sp. 812 and was termed enterocin T.
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Cobo Molinos, Antonio; Abriouel, Hikmate; Lucas López, Rosario; Ben Omar, Nabil; Valdivia, Eva; Gálvez, Antonio
2008-09-01
Enterocin AS-48 is a broad-spectrum cyclic antimicrobial peptide produced by Enterococcus faecalis. In the present study, the bacteriocin was tested alone and in combination with other antimicrobials for decontamination of Bacillus inoculated on alfalfa, soybean sprouts and green asparagus. Washing with enterocin AS-48 solutions reduced viable cell counts of Bacillus cereus and Bacillus weihenstephanensis by 1.0-1.5 and by 1.5-2.38 log units right after application of treatment, respectively. In both cases, the bacteriocin was effective in reducing the remaining viable population below detection levels during further storage of the samples at 6 degrees C, but failed to prevent regrowth in samples stored at 15 or 22 degrees C. Application of washing treatments containing enterocin AS-48 in combination with several other antimicrobials and sanitizers (cinnamic and hydrocinnamic acids, carvacrol, polyphosphoric acid, peracetic acid, hexadecylpyridinium chloride and sodium hypochlorite) greatly enhanced the bactericidal effects. The combinations of AS-48 and sodium hypochlorite, peracetic acid or hexadecylpyridinium chloride provided the best results. After application of the combined treatments on alfalfa sprouts contaminated with B. cereus or with B. weihenstephanensis, viable bacilli were not detected or remained at very low concentrations in the treated samples during a 1-week storage period at 15 degrees C. Inhibition of B. cereus by in situ produced bacteriocin was tested by cocultivation with the AS-48 producer strain E. faecalis A-48-32 inoculated on soybean sprouts. Strain A-48-32 was able to grow and produce bacteriocin on sprouts both at 15 and 22 degrees C. At 15 degrees C, growth of B. cereus was completely inhibited in the cocultures, while a much more limited effect was observed at 22 degrees C. The results obtained for washing treatments are very encouraging for the application of enterocin AS-48 in the decontamination of sprouts. Application of washing
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Enterocin AS-48 as Evidence for the Use of Bacteriocins as New Leishmanicidal Agents.
Abengózar, María Ángeles; Cebrián, Rubén; Saugar, José María; Gárate, Teresa; Valdivia, Eva; Martínez-Bueno, Manuel; Maqueda, Mercedes; Rivas, Luis
2017-04-01
We report the feasibility of enterocin AS-48, a circular cationic peptide produced by Enterococcus faecalis , as a new leishmanicidal agent. AS-48 is lethal to Leishmania promastigotes as well as to axenic and intracellular amastigotes at low micromolar concentrations, with scarce cytotoxicity to macrophages. AS-48 induced a fast bioenergetic collapse of L. donovani promastigotes but only a partial permeation of their plasma membrane with limited entrance of vital dyes, even at concentrations beyond its full lethality. Fluoresceinated AS-48 was visualized inside parasites by confocal microscopy and seen to cause mitochondrial depolarization and reactive oxygen species production. Altogether, AS-48 appeared to have a mixed leishmanicidal mechanism that includes both plasma membrane permeabilization and additional intracellular targets, with mitochondrial dysfunctionality being of special relevance. This complex leishmanicidal mechanism of AS-48 persisted even for the killing of intracellular amastigotes, as evidenced by transmission electron microscopy. We demonstrated the potentiality of AS-48 as a new and safe leishmanicidal agent, expanding the growing repertoire of eukaryotic targets for bacteriocins, and our results provide a proof of mechanism for the search of new leishmanicidal bacteriocins, whose diversity constitutes an almost endless source for new structures at moderate production cost and whose safe use on food preservation is well established. Copyright © 2017 American Society for Microbiology.
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Ben Braïek, Olfa; Ghomrassi, Hamdi; Cremonesi, Paola; Morandi, Stefano; Fleury, Yannick; Le Chevalier, Patrick; Hani, Khaled; Bel Hadj, Omrane; Ghrairi, Taoufik
2017-06-01
Screening for lactic acid bacteria (LAB) from fresh shrimp samples (Penaeus vannamei) collected from retail seafood markets in the Tunisian's coast, resulted in the isolation of an Enterococcus strain termed Q1. This strain was selected for its antagonistic activity against pathogenic bacteria such as Listeria monocytogenes, Pseudomonas aeruginosa, Lactococcus garvieae and against fungi (Aspergillus niger and Fusarium equiseti). The Q1 strain was characterised using standard morphological and biochemical tests, growth assays at different temperatures, pH and salinity. 16S rRNA, rpoA and pheS gene sequencing, as well as the 16S-23S rRNA intergenic spacer analyses, were combined to identify strain Q1 as a strain of Enterococcus lactis. The bacteriocin produced by E. lactis Q1 is thermostable, active in the pH range from 4.0 to 9.0 and has a bactericidal mode of action. The enterocin P structural gene was detected by specific PCR in strain E. lactis Q1, which is in good agreement with SDS-PAGE data of the purified bacteriocin. A lack of significant antibiotic resistance genes and virulence determinants was confirmed by specific PCRs. This work provides the first description of an enterocin P producer E. lactis strain isolated from a fresh shrimp. Based on its safety properties (absence of haemolytic activity, virulence factors and antibiotic resistance genes), this strain has the potential to be used as a natural additive or adjunct protective culture in food biopreservation and/or probiotic culture.
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Insights into the functionality of the putative residues involved in enterocin AS-48 maturation.
Cebrián, Rubén; Maqueda, Mercedes; Neira, José Luis; Valdivia, Eva; Martínez-Bueno, Manuel; Montalbán-López, Manuel
2010-11-01
AS-48 is a 70-residue, α-helical, cationic bacteriocin produced by Enterococcus faecalis and is very singular in its circular structure and its broad antibacterial spectrum. The AS-48 preprotein consists of an N-terminal signal peptide (SP) (35 residues) followed by a proprotein moiety that undergoes posttranslational modifications to yield the mature and active circular protein. For the study of the specificity of the region of AS-48 that is responsible for maturation, three single mutants have been generated by site-directed mutagenesis in the as-48A structural gene. The substitutions were made just in the residues that are thought to constitute a recognition site for the SP cleavage enzyme (His-1, Met1) and in those involved in circularization (Met1, Trp70). Each derivative was expressed in the enterococcal JH2-2 strain containing the necessary native biosynthetic machinery for enterocin production. The importance of these derivatives in AS-48 processing has been evaluated on the basis of the production and structural characterization of the corresponding derivatives. Notably, only two of them (Trp70Ala and Met1Ala derivatives) could be purified in different forms and amounts and are characterized for their bactericidal activity and secondary structure. We could not detect any production of AS-48 in JH2-2(pAM401-81(His-1Ile)) by using the conventional chromatographic techniques, despite the high efficiency of the culture conditions applied to produce this enterocin. Our results underline the different important roles of the mutated residues in (i) the elimination of the SP, (ii) the production levels and antibacterial activity of the mature proteins, and (iii) protein circularization. Moreover, our findings suggest that His-1 is critically involved in cleavage site recognition, its substitution being responsible for the blockage of processing, thereby hampering the production of the specific protein in the cellular culture supernatant.
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Directory of Open Access Journals (Sweden)
Gálvez Antonio
2009-10-01
Full Text Available Abstract Background Enterocin AS-48 is produced by Enterococcus faecalis S48 to compete with other bacteria in their environment. Due to its activity against various Gram positive and some Gram negative bacteria it has clear potential for use as a food preservative. Here, we studied the effect of enterocin AS-48 challenges on vegetative cells of Bacillus cereus ATCC 14579 by use of transcriptome analysis. Results Of the 5200 genes analysed, expression of 24 genes was found to change significantly after a 30 min treatment with a subinhibitory bacteriocin concentration of 0.5 μg/ml. Most of up-regulated genes encode membrane-associated or secreted proteins with putative transmembrane segments or signal sequences, respectively. One operon involved in arginine metabolism was significantly downregulated. The BC4206-BC4207 operon was found to be the most upregulated target in our experiments. BC4206 codes for a PadR type transcriptional regulator, while BC4207 codes for a hypothetical membrane protein. The operon structure and genes are conserved in B. cereus and B. thuringiensis species, but are not present in B. anthracis and B. subtilis. Using real-time qPCR, we show that these genes are upregulated when we treated the cells with AS-48, but not upon nisin treatment. Upon overexpression of BC4207 in B. cereus, we observed an increased resistance against AS-48. Expression of BC4207 in B. subtilis 168, which lacks this operon also showed increased resistance against AS-48. Conclusion BC4207 membrane protein is involved in the resistance mechanism of B. cereus cells against AS-48.
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Di Martino, Maria Letizia; Romilly, Cédric; Wagner, E Gerhart H; Colonna, Bianca; Prosseda, Gianni
2016-11-08
VirF, an AraC-like activator, is required to trigger a regulatory cascade that initiates the invasive program of Shigella spp., the etiological agents of bacillary dysentery in humans. VirF expression is activated upon entry into the host and depends on many environmental signals. Here, we show that the virF mRNA is translated into two proteins, the major form, VirF 30 (30 kDa), and the shorter VirF 21 (21 kDa), lacking the N-terminal segment. By site-specific mutagenesis and toeprint analysis, we identified the translation start sites of VirF 30 and VirF 21 and showed that the two different forms of VirF arise from differential translation. Interestingly, in vitro and in vivo translation experiments showed that VirF 21 is also translated from a leaderless mRNA (llmRNA) whose 5' end is at position +309/+310, only 1 or 2 nucleotides upstream of the ATG84 start codon of VirF 21 The llmRNA is transcribed from a gene-internal promoter, which we identified here. Functional analysis revealed that while VirF 30 is responsible for activation of the virulence system, VirF 21 negatively autoregulates virF expression itself. Since VirF 21 modulates the intracellular VirF levels, this suggests that transcription of the llmRNA might occur when the onset of the virulence program is not required. We speculate that environmental cues, like stress conditions, may promote changes in virF mRNA transcription and preferential translation of llmRNA. Shigella spp. are a major cause of dysentery in humans. In bacteria of this genus, the activation of the invasive program involves a multitude of signals that act on all layers of the gene regulatory hierarchy. By controlling the essential genes for host cell invasion, VirF is the key regulator of the switch from the noninvasive to the invasive phenotype. Here, we show that the Shigella virF gene encodes two proteins of different sizes, VirF 30 and VirF 21 , that are functionally distinct. The major form, VirF 30 , activates the genes
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File list: Oth.CeL.50.Clamp.AllCell [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available Oth.CeL.50.Clamp.AllCell dm3 TFs and others Clamp Cell line SRX159172,SRX159170,SRX...159174,SRX159166,SRX159173 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.50.Clamp.AllCell.bed ...
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Franz, Charles M. A. P.; Worobo, Randy W.; Quadri, Luis E. N.; Schillinger, Ulrich; Holzapfel, Wilhelm H.; Vederas, John C.; Stiles, Michael E.
1999-01-01
A purified bacteriocin produced by Enterococcus faecium BFE 900 isolated from black olives was shown by Edman degradation and mass spectrometric analyses to be identical to enterocin B produced by E. faecium T136 from meat (P. Casaus, T. Nilsen, L. M. Cintas, I. F. Nes, P. E. Hernández, and H. Holo, Microbiology 143:2287–2294, 1997). The structural gene was located on a 2.2-kb HindIII fragment and a 12.0-kb EcoRI chromosomal fragment. The genetic characteristics and production of EntB by E. faecium BFE 900 differed from that described so far by the presence of a conserved sequence like a regulatory box upstream of the EntB gene, and its production was constitutive and not regulated. The 2.2-kb chromosomal fragment contained the hitherto undetected immunity gene for EntB in an atypical orientation that is the reverse of that of the structural gene. Typical transport and other genes associated with bacteriocin production were not detected on the 12.0-kb chromosomal fragment containing the EntB structural gene. This makes the EntB genetic system different from most other bacteriocin systems, where transport and possible regulatory genes are clustered. EntB was subcloned and expressed by the dedicated secretion machinery of Carnobacterium piscicola LV17A. The structural gene was amplified by PCR, fused to the divergicin A signal peptide, and expressed by the general secretory pathway in Enterococcus faecalis ATCC 19433. PMID:10224016
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File list: Oth.CeL.50.Epitope_tags.AllCell [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available Oth.CeL.50.Epitope_tags.AllCell dm3 TFs and others Epitope tags Cell line SRX099638...099636 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Oth.CeL.50.Epitope_tags.AllCell.bed ...
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Directory of Open Access Journals (Sweden)
Irene Ortega Blázquez
2017-11-01
Full Text Available The aim of the present study was to determine the efficacy of films activated with enterocin AS-48 plus thymol singly, or in combination with high-hydrostatic pressure (HHP on the inactivation of Listeria innocua in sea bream fillets and in fruit puree stored under refrigeration for 10 days. L. innocua proliferated in control fish fillets during storage. The activated film reduced viable Listeria counts in fillets by 1.76 log cycles and prevented growth of survivors until mid-storage. Application of HHP treatment to fillets packed in films without antimicrobials reduced Listeria counts by 1.83 log cycles, but did not prevent the growth of survivors during storage. The combined treatment reduced viable counts by 1.88 log cycles and delayed growth of survivors during the whole storage period. L. innocua survived in puree during storage. The activated film reduced Listeria counts by 1.80 and 2.0 log cycles at days 0 and 3. After that point, Listeria were below the detection limit. No viable Listeria were detected in the purees after application of HHP treatment singly, or in combination with the activated film. Results from the study indicate that the efficacy of activated films against Listeria is markedly influenced by the food type.
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File list: Pol.CeL.50.RNA_polymerase_II.AllCell [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available Pol.CeL.50.RNA_polymerase_II.AllCell dm3 RNA polymerase RNA polymerase II Cell line...70,SRX749072,SRX749071,SRX749073,SRX017852,SRX529168 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.CeL.50.RNA_polymerase_II.AllCell.bed ...
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International Nuclear Information System (INIS)
Shigeno, Yuta; Uchiumi, Toshio; Nomura, Takaomi
2016-01-01
Ribosomal protein L6, an essential component of the large (50S) subunit, primarily binds to helix 97 of 23S rRNA and locates near the sarcin/ricin loop of helix 95 that directly interacts with GTPase translation factors. Although L6 is believed to play important roles in factor-dependent ribosomal function, crucial biochemical evidence for this hypothesis has not been obtained. We constructed and characterized an Escherichia coli mutant bearing a chromosomal L6 gene (rplF) disruption and carrying a plasmid with an arabinose-inducible L6 gene. Although this ΔL6 mutant grew more slowly than its wild-type parent, it proliferated in the presence of arabinose. Interestingly, cell growth in the absence of arabinose was biphasic. Early growth lasted only a few generations (LI-phase) and was followed by a suspension of growth for several hours (S-phase). This suspension was followed by a second growth phase (LII-phase). Cells harvested at both LI- and S-phases contained ribosomes with reduced factor-dependent GTPase activity and accumulated 50S subunit precursors (45S particles). The 45S particles completely lacked L6. Complete 50S subunits containing L6 were observed in all growth phases regardless of the L6-depleted condition, implying that the ΔL6 mutant escaped death because of a leaky expression of L6 from the complementing plasmid. We conclude that L6 is essential for the assembly of functional 50S subunits at the late stage. We thus established conditions for the isolation of L6-depleted 50S subunits, which are essential to study the role of L6 in translation. - Highlights: • We constructed an in vivo functional assay system for Escherichia coli ribosomal protein L6. • Growth of an E. coli ΔL6 mutant was biphasic when L6 levels were depleted. • The ΔL6 mutant accumulated 50S ribosomal subunit precursors that sedimented at 45S. • L6 is a key player in the late stage of E. coli 50S subunit assembly.
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Energy Technology Data Exchange (ETDEWEB)
Shigeno, Yuta [Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567 (Japan); Uchiumi, Toshio [Department of Biology, Faculty of Science, Niigata University, Niigata 950-2181 (Japan); Nomura, Takaomi, E-mail: nomurat@shinshu-u.ac.jp [Division of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567 (Japan)
2016-04-22
Ribosomal protein L6, an essential component of the large (50S) subunit, primarily binds to helix 97 of 23S rRNA and locates near the sarcin/ricin loop of helix 95 that directly interacts with GTPase translation factors. Although L6 is believed to play important roles in factor-dependent ribosomal function, crucial biochemical evidence for this hypothesis has not been obtained. We constructed and characterized an Escherichia coli mutant bearing a chromosomal L6 gene (rplF) disruption and carrying a plasmid with an arabinose-inducible L6 gene. Although this ΔL6 mutant grew more slowly than its wild-type parent, it proliferated in the presence of arabinose. Interestingly, cell growth in the absence of arabinose was biphasic. Early growth lasted only a few generations (LI-phase) and was followed by a suspension of growth for several hours (S-phase). This suspension was followed by a second growth phase (LII-phase). Cells harvested at both LI- and S-phases contained ribosomes with reduced factor-dependent GTPase activity and accumulated 50S subunit precursors (45S particles). The 45S particles completely lacked L6. Complete 50S subunits containing L6 were observed in all growth phases regardless of the L6-depleted condition, implying that the ΔL6 mutant escaped death because of a leaky expression of L6 from the complementing plasmid. We conclude that L6 is essential for the assembly of functional 50S subunits at the late stage. We thus established conditions for the isolation of L6-depleted 50S subunits, which are essential to study the role of L6 in translation. - Highlights: • We constructed an in vivo functional assay system for Escherichia coli ribosomal protein L6. • Growth of an E. coli ΔL6 mutant was biphasic when L6 levels were depleted. • The ΔL6 mutant accumulated 50S ribosomal subunit precursors that sedimented at 45S. • L6 is a key player in the late stage of E. coli 50S subunit assembly.
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Directory of Open Access Journals (Sweden)
Andrea Lauková
2009-01-01
Full Text Available Enterococci isolated from the crop and caecum of Japanese quails exposed to 7 day conditions of microgravity were re-vitalized after their dry-freezing long storage. Originally, the strains were isolated from Japanese quails after their landing from flight onboard the orbital station Mir during the experiment in August 1990. Because taxonomy as well as the studies concerning the bacteriocins, especially those produced by enterococci, have been continually developed for years, the aim of this study was to confirm species identification, stability of the properties of enterococci as well as to test new properties after their long storage. Genotyping allotted the strains to the species E. faecium. Lactic acid production was detected in similar amounts in the strains before and after their long-storage in dry-frozen form. The strains were vancomycinsensitive and kanamycin-resistant before as well as after their long-time storage. Variability in sensitivity to different antibiotics was found among the strains tested even before and after longtime storage. Each of the strains possessed at least one structural enterocin gene. The structural genes for enterocin A, P, B, L50B were detected in E. faecium EP7. E. faecium EP2, EEP4 have the genes for ent A, B, L50B. The gene for ent P was detected only in the strain EP7. The most often detected was ent A gene followed by ent genes B, L50B. All strains inhibited growth of at least 4 out of 15 indicators. The stability of the enterococcal properties determined before as well as after their dry-freezing was not influenced during their long-term storage; moreover, new properties were determined.
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Borrero, Juan; Kunze, Gotthard; Jiménez, Juan J; Böer, Erik; Gútiez, Loreto; Herranz, Carmen; Cintas, Luis M; Hernández, Pablo E
2012-08-01
The bacteriocin enterocin A (EntA) produced by Enterococcus faecium T136 has been successfully cloned and produced by the yeasts Pichia pastoris X-33EA, Kluyveromyces lactis GG799EA, Hansenula polymorpha KL8-1EA, and Arxula adeninivorans G1212EA. Moreover, P. pastoris X-33EA and K. lactis GG799EA produced EntA in larger amounts and with higher antimicrobial and specific antimicrobial activities than the EntA produced by E. faecium T136.
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Arbulu, Sara; Lohans, Christopher T; van Belkum, Marco J; Cintas, Luis M; Herranz, Carmen; Vederas, John C; Hernández, Pablo E
2015-12-16
The solution structure of enterocin HF (EntHF), a class IIa bacteriocin of 43 amino acids produced by Enterococcus faecium M3K31, was evaluated by CD and NMR spectroscopy. Purified EntHF was unstructured in water, but CD analysis supports that EntHF adopts an α-helical conformation when exposed to increasing concentrations of trifluoroethanol. Furthermore, NMR spectroscopy indicates that this bacteriocin adopts an antiparallel β-sheet structure in the N-terminal region (residues 1-17), followed by a well-defined central α-helix (residues 19-30) and a more disordered C-terminal end (residues 31-43). EntHF could be structurally organized into three flexible regions that might act in a coordinated manner. This is in agreement with the absence of long-range nuclear Overhauser effect signals between the β-sheet domain and the C-terminal end of the bacteriocin. The 3D structure recorded for EntHF fits emerging facts regarding target recognition and mode of action of class IIa bacteriocins.
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Penentuan Nilai Ld50 Ekstrak Etanol Bawang Bombay (Allium Cepa L.) Pada Mencit Jantan
Amalia, Nofria Rizki
2017-01-01
131501110 LD50 (Lethal Dose50) merupakan salah satu parameter yang dapat menentukan derajat toksisitas suatu bahan. Uji toksisitas ini mengevaluasi besarnya dosis yang dapat menimbulkan efek toksik dan kematian pada hewan uji. Bawang bombay (Allium cepa L.) memiliki khasiat sebagaiantibakteri, antioksidan, antimutagenik, dan antiinflamasi. Tujuandaripenelitianiniadalahuntuk menentukan nilai LD50dariekstraketanolbawang bombaypadamencitjantan. Penelitianinimerupakanpenelitianeksperimental...
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Ben Braïek, Olfa; Cremonesi, Paola; Morandi, Stefano; Smaoui, Slim; Hani, Khaled; Ghrairi, Taoufik
2018-03-07
This study aims to characterise a potential bacteriocinogenic lactic acid bacterial strain isolated from a raw pink shrimp (Palaemon serratus) and evaluate its safety aspect. The strain designated as 4CP3 was noted to display antibacterial activities (P enterocins A, B and P. To our knowledge, this feature is newly described for E. lactis strain isolated from raw shrimps. Regarding safety aspect of E. lactis 4CP3, it has been demonstrated that this strain was not haemolytic, gelatinase negative, sensitive to vancomycin, and free of common antibiotic resistance genes and virulence factors. Therefore, it may be useful as a safe natural agent in preservation of foods or as a new probiotic strain in food and feed. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Czech Academy of Sciences Publication Activity Database
Pompa, A.; De Marchis, F.; Pallotta, M. T.; Benitez-Alfonso, Y.; Jones, A.; Schipper, K.; Moreau, K.; Žárský, Viktor; Di Sansebastiano, G. P.; Bellucci, M.
2017-01-01
Roč. 18, č. 4 (2017), č. článku 703. E-ISSN 1422-0067 Institutional support: RVO:61389030 Keywords : Autophagy * Exosomes * Intercellular channels * Leaderless proteins * Protein secretion * Trafficking mechanisms * Unconventional secretion Subject RIV: EA - Cell Biology OBOR OECD: Developmental biology Impact factor: 3.226, year: 2016
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Directory of Open Access Journals (Sweden)
Maria Letizia Di Martino
2016-11-01
Full Text Available VirF, an AraC-like activator, is required to trigger a regulatory cascade that initiates the invasive program of Shigella spp., the etiological agents of bacillary dysentery in humans. VirF expression is activated upon entry into the host and depends on many environmental signals. Here, we show that the virF mRNA is translated into two proteins, the major form, VirF30 (30 kDa, and the shorter VirF21 (21 kDa, lacking the N-terminal segment. By site-specific mutagenesis and toeprint analysis, we identified the translation start sites of VirF30 and VirF21 and showed that the two different forms of VirF arise from differential translation. Interestingly, in vitro and in vivo translation experiments showed that VirF21 is also translated from a leaderless mRNA (llmRNA whose 5′ end is at position +309/+310, only 1 or 2 nucleotides upstream of the ATG84 start codon of VirF21. The llmRNA is transcribed from a gene-internal promoter, which we identified here. Functional analysis revealed that while VirF30 is responsible for activation of the virulence system, VirF21 negatively autoregulates virF expression itself. Since VirF21 modulates the intracellular VirF levels, this suggests that transcription of the llmRNA might occur when the onset of the virulence program is not required. We speculate that environmental cues, like stress conditions, may promote changes in virF mRNA transcription and preferential translation of llmRNA.
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Directory of Open Access Journals (Sweden)
Arilmi Gorriti
2010-09-01
Full Text Available Objetivos. Evaluar la toxicidad oral a 60 días y determinar la dosis letal 50 (DL 50 de los aceites crudos de sacha inchi (Plukenetia volubilis L. y linaza (Linum ussitatisimum en ratas Holtzman y en ratones cepa Balb C57, respectivamente. Materiales y métodos. Para la evaluación de la toxicidad oral a dosis repetida por 60 días se utilizó 24 ratas macho Holtzman divididos en tres grupos de ocho cada uno, los grupos fueron: solución salina fisiológica 4 mL/kg (SSF, aceite de sacha inchi 0,5 mL/kg (SI05 y aceite de linaza 0,5 mL/kg (L05, durante el experimento se controló semanalmente el peso corporal y signos de toxicidad en los grupos investigados, así como colesterol total, HDL, triglicéridos, glucosa, urea, TGP y fosfatasa alcalina a los 30 y 60 días de iniciado el experimento. Para la evaluación de la DL50 se usó ratones macho cepa Balb C57 en grupos de diez animales, se administró por vía oral dosis crecientes de aceites crudos hasta alcanzar 1 mL/kg (37 g/kg; Resultados. Los parámetros séricos en las ratas indican que no existe toxicidad alguna a los 60 días y que la administración de los aceites disminuyeron los niveles de colesterol, triglicéridos e incrementaron el HDL con respecto al grupo control. La DL50 muestra que los aceites crudos de sacha inchi y linaza presentan dosis por encima de los 37 g/kg de masa corporal. Conclusiones. Los aceites de sacha inchi y linaza son inocuos a 60 días y presentan una DL50 por encima de los 37 g/kg de animal.Objectives. To evaluate the oral toxicity at 60 days and to determine the lethal dose 50 (LD 50 of raw sacha inchi (Plukenetia volubilis L. and linseed (Linum ussitatisimum oils in Holtzman rats and mice of the strain Balb C57 respectively. Materials and methods. For the evaluation of the oral toxicity of repeated doses for 60 days, 24 male Holtzman rats were used, divided in three groups of 8 each, the groups were: physiologic saline solution 4 mL/kg (FSS, sacha inchi oil
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Directory of Open Access Journals (Sweden)
Kathryn Geldart
2016-10-01
Full Text Available Antimicrobial peptides are a promising alternative to traditional antibiotics, but their utility is limited by high production costs and poor bioavailability profiles. Bacterial production and delivery of antimicrobial peptides (AMPs directly at the site of infection may offer a path for effective therapeutic application. In this study, we have developed a vector that can be used for the production and secretion of seven antimicrobial peptides from both Escherichia coli MC1061 F’ and probiotic E.coli Nissle 1917. The vector pMPES (Modular Peptide Expression System employs the Microcin V (MccV secretion system and a powerful synthetic promoter to drive AMP production. Herein, we demonstrate the capacity of pMPES to produce inhibitory levels of MccV, Microcin L (MccL, Microcin N (McnN, Enterocin A (EntA, Enterocin P (EntP, Hiracin JM79 (HirJM79 and Enterocin B (EntB. To our knowledge, this is the first demonstration of such a broadly-applicable secretion system for AMP production. This type of modular expression system could expedite the development of sorely needed antimicrobial technologies
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Ishibashi, Naoki; Himeno, Kohei; Fujita, Koji; Masuda, Yoshimitsu; Perez, Rodney Honrada; Zendo, Takeshi; Wilaipun, Pongtep; Leelawatcharamas, Vichien; Nakayama, Jiro; Sonomoto, Kenji
2012-01-01
Enterocins NKR-5-3A, B, C, and D were purified from the culture supernatant of Enterococcus faecium NKR-5-3 and characterized. Among the four purified peptides, enterocin NKR-5-3A (5242.3 Da) was identical to brochocin A, produced by Brochothrix campestris ATCC 43754, in mature peptides, and its putative synergistic peptide, enterocin NKR-5-3Z, was found to be encoded in ent53Z downstream of ent53A, encoding enterocin NKR-5-3A. Enterocin NKR-5-3B (6316.4 Da) showed a broad antimicrobial spectrum, and enterocin NKR-5-3C (4512.8 Da) showed high activity against Listeria. Enterocin NKR-5-3D (2843.5 Da), showing high homology to an inducing peptide produced by Lactobacillus sakei 5, induced the production of the enterocins. The enterocins showed different antimicrobial spectra and intensities. E. faecium NKR-5-3 concomitantly produced enterocins NKR-5-3A, B, C, and D which probably belong to different classes of bacteriocins. Furthermore, NKR-5-3 production was induced by enterocin NKR-5-3D.
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Analysis of the promoters involved in enterocin AS-48 expression.
Cebrián, Rubén; Rodríguez-Ruano, Sonia; Martínez-Bueno, Manuel; Valdivia, Eva; Maqueda, Mercedes; Montalbán-López, Manuel
2014-01-01
The enterocin AS-48 is the best characterized antibacterial circular protein in prokaryotes. It is a hydrophobic and cationic bacteriocin, which is ribosomally synthesized by enterococcal cells and post-translationally cyclized by a head-to-tail peptide bond. The production of and immunity towards AS-48 depend upon the coordinated expression of ten genes organized in two operons, as-48ABC (where genes encoding enzymes with processing, secretion, and immunity functions are adjacent to the structural as-48A gene) and as-48C1DD1EFGH. The current study describes the identification of the promoters involved in AS-48 expression. Seven putative promoters have been here amplified, and separately inserted into the promoter-probe vector pTLR1, to create transcriptional fusions with the mCherry gene used as a reporter. The activity of these promoter regions was assessed measuring the expression of the fluorescent mCherry protein using the constitutive pneumococcal promoter PX as a reference. Our results revealed that only three promoters PA, P2(2) and PD1 were recognized in Enterococcus faecalis, Lactococcus lactis and Escherichia coli, in the conditions tested. The maximal fluorescence was obtained with PX in all the strains, followed by the P2(2) promoter, which level of fluorescence was 2-fold compared to PA and 4-fold compared to PD1. Analysis of putative factors influencing the promoter activity in single and double transformants in E. faecalis JH2-2 demonstrated that, in general, a better expression was achieved in presence of pAM401-81. In addition, the P2(2) promoter could be regulated in a negative fashion by genes existing in the native pMB-2 plasmid other than those of the as-48 cluster, while the pH seems to affect differently the as-48 promoter expression.
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Analysis of the promoters involved in enterocin AS-48 expression.
Directory of Open Access Journals (Sweden)
Rubén Cebrián
Full Text Available The enterocin AS-48 is the best characterized antibacterial circular protein in prokaryotes. It is a hydrophobic and cationic bacteriocin, which is ribosomally synthesized by enterococcal cells and post-translationally cyclized by a head-to-tail peptide bond. The production of and immunity towards AS-48 depend upon the coordinated expression of ten genes organized in two operons, as-48ABC (where genes encoding enzymes with processing, secretion, and immunity functions are adjacent to the structural as-48A gene and as-48C1DD1EFGH. The current study describes the identification of the promoters involved in AS-48 expression. Seven putative promoters have been here amplified, and separately inserted into the promoter-probe vector pTLR1, to create transcriptional fusions with the mCherry gene used as a reporter. The activity of these promoter regions was assessed measuring the expression of the fluorescent mCherry protein using the constitutive pneumococcal promoter PX as a reference. Our results revealed that only three promoters PA, P2(2 and PD1 were recognized in Enterococcus faecalis, Lactococcus lactis and Escherichia coli, in the conditions tested. The maximal fluorescence was obtained with PX in all the strains, followed by the P2(2 promoter, which level of fluorescence was 2-fold compared to PA and 4-fold compared to PD1. Analysis of putative factors influencing the promoter activity in single and double transformants in E. faecalis JH2-2 demonstrated that, in general, a better expression was achieved in presence of pAM401-81. In addition, the P2(2 promoter could be regulated in a negative fashion by genes existing in the native pMB-2 plasmid other than those of the as-48 cluster, while the pH seems to affect differently the as-48 promoter expression.
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Floriano, Belén; Ruiz-Barba, José L.; Jiménez-Díaz, Rufino
1998-01-01
Enterocin I (ENTI) is a novel bacteriocin produced by Enterococcus faecium 6T1a, a strain originally isolated from a Spanish-style green olive fermentation. The bacteriocin is active against many olive spoilage and food-borne gram-positive pathogenic bacteria, including clostridia, propionibacteria, and Listeria monocytogenes. ENTI was purified to homogeneity by ammonium sulfate precipitation, binding to an SP-Sepharose fast-flow column, and phenyl-Sepharose CL-4B and C2/C18 reverse-phase chromatography. The purification procedure resulted in a final yield of 954% and a 170,000-fold increase in specific activity. The primary structure of ENTI was determined by amino acid and nucleotide sequencing. ENTI consists of 44 amino acids and does not show significant sequence similarity with any other previously described bacteriocin. Sequencing of the entI structural gene, which is located on the 23-kb plasmid pEF1 of E. faecium 6T1a, revealed the absence of a leader peptide at the N-terminal region of the gene product. A second open reading frame, ORF2, located downstream of entI, encodes a putative protein that is 72.7% identical to ENTI. entI and ORF2 appear to be cotranscribed, yielding an mRNA of ca. 0.35 kb. A gene encoding immunity to ENTI was not identified. However, curing experiments demonstrated that both enterocin production and immunity are conferred by pEF1. PMID:9835578
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Pashkova, Tatiana M; Vasilchenko, Alexey S; Khlopko, Yuriy A; Kochkina, Elena E; Kartashova, Olga L; Sycheva, Maria V
2018-03-08
We report here the complete genome sequence of Enterococcus faecium strain ICIS 96, which was isolated from the feces of a horse. Bacteriological characterization of strain ICIS 96 revealed the absence of pathogenicity factors, while its spectrum of antagonistic activity was found to be broad, having activities associated with both Gram-positive and Gram-negative bacteria. Analysis of the E. faecium ICIS 96 genome revealed five genes associated with antimicrobial activity (enterocin [ent] A, ent B, lactobin A/cerein 7b, and ent L50 A/B). No genes that correlate with human pathogenicity were identified. Copyright © 2018 Pashkova et al.
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den Dunnen, WFA; Meek, MF; Grijpma, DW; Robinson, PF; Schakenraad, JM
2000-01-01
Nerve guides can be used for the reconstruction of peripheral nerve defects. After serving their function, nerve guides should degrade. p[(50)/(50) ((85)/(L)(15)/(D))LA/epsilon-CL] degrades completely within 1 year without the formation of a slow degrading crystalline fraction. Although the tensile
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Achemchem, Fouad; Abrini, Jamal; Martínez-Bueno, Manuel; Valdivia, Eva; Maqueda, Mercedes
2006-10-01
The bacteriocinogenic Enterococcus faecium F58 strain, a natural goat's jben cheese isolate, lacks decarboxylase activity involved in most biogenic amine formation. It was also sensitive to 13 antibiotics assayed and free of virulence and vancomycin resistance genes. The F58 strain reached the stationary phase after 12 h of growth in sterile goat's milk, and the production of enterocin F-58 (Ent L50) was first detected after 48 h (400 AU/ml), thereafter remaining stable up to 5 days. The effectiveness of the F58 strain in controlling Listeria monocytogenes serovar 4b in reduced fat and whole goat's milk, and in goat's jben has been examined. Coculture experiments of F58-L. monocytogenes in both types of milk demonstrated that listeriae were not eliminated, although reductions by 1 to 4 log units were found. Nevertheless, when the F58 strain was previously inoculated in whole milk and left to grow for 12 h before contamination, the pathogen was completely eliminated after 130 h of coculture. Production of jben cheese contaminated with L. monocytogenes prior to packaging, using preparations of F58-producer strain, caused a significant decrease in the number of viable listeriae, which were undetectable after 1 week of cheese storage at 22 degrees C. Altogether, results from this study suggest that E. faecium F58 strain may be used as an adjunct culture in cheese to control contamination and growth of L. monocytogenes by in situ enterocin production, thus providing an additional hurdle to enhance control of this pathogen.
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Directory of Open Access Journals (Sweden)
Eleftherios H. Drosinos
2016-08-01
Full Text Available The aim of the present study was to assess the expression of key virulence genes during co-culture of L. monocytogenes with a bacteriocinogenic E. faecium strain in liquid growth medium. For that purpose, BHI broth was inoculated with 7 log CFU·mL–1 L. monocytogenes and 4, 5 or 6 log CFU·mL–1 E. faecium. Sampling took place after 8 and 24 h of incubation, corresponding to the maximum and minimum of enterocin production, respectively. The RNA was extracted, stabilized and expression of prfA, sigB, hly, plcA, plcB, inlA, inlB, inlC and inlJ, was assessed by RT-qPCR. Most of the genes were downregulated during co-culture at 5 °C. Moreover, a statistically significant effect of the inoculum level was evident in most of the cases. On the contrary, no effect on the transcription level of most of the genes was observed during co-culture at 37 °C.
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Martín-Platero, Antonio M.; Valdivia, Eva; Ruíz-Rodríguez, Magdalena; Soler, Juan J.; Martín-Vivaldi, Manuel; Maqueda, Mercedes; Martínez-Bueno, Manuel
2006-01-01
The uropygial gland (preen gland) is a holocrine secretory gland situated at the base of the tail in birds which produces a hydrophobic fatty secretion. In certain birds, such as the hoopoe, Upupa epops, the composition of this secretion is influenced by both seasonal and sexual factors, becoming darker and more malodorous in females and in their nestlings during the nesting phase. The secretion is spread throughout the plumage when the bird preens itself, leaving its feathers flexible and waterproof. It is also thought to play a role in defending the bird against predators and parasites. We have isolated from the uropygial secretion of a nestling a bacterium that grows in monospecific culture which we have identified unambiguously by phenotypic and genotypic means as Enterococcus faecalis. The strain in question produces antibacterial substances that are active against all gram-positive bacteria assayed and also against some gram-negative strains. Its peptide nature identifies it as a bacteriocin within the group known as enterocins. Two peptides were purified to homogeneity (MR10A and MR10B), and matrix-assisted laser desorption ionization-time of flight (mass spectrometry) analysis showed masses of 5201.58 and 5207.7 Da, respectively. Amino acid sequencing of both peptides revealed high similarity with enterocin L50A and L50B (L. M. Cintas, P. Casaus, H. Holo, P. E. Hernández, I. F. Nes, and L. S. Håvarstein, J. Bacteriol. 180:1988-1994, 1998). PCR amplification of total DNA from strain MRR10-3 with primers for the L50A/B structural genes and sequencing of the amplified fragment revealed almost identical sequences, except for a single conservative change in residue 38 (Glu→Asp) in MR10A and two changes in residues 9 (Thr→Ala) and 15 (Leu→Phe) in MR10B. This is the first time that the production of bacteriocins by a bacterium isolated from the uropygial gland has been described. The production of these broad-spectrum antibacterial substances by an
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Martín-Platero, Antonio M; Valdivia, Eva; Ruíz-Rodríguez, Magdalena; Soler, Juan J; Martín-Vivaldi, Manuel; Maqueda, Mercedes; Martínez-Bueno, Manuel
2006-06-01
The uropygial gland (preen gland) is a holocrine secretory gland situated at the base of the tail in birds which produces a hydrophobic fatty secretion. In certain birds, such as the hoopoe, Upupa epops, the composition of this secretion is influenced by both seasonal and sexual factors, becoming darker and more malodorous in females and in their nestlings during the nesting phase. The secretion is spread throughout the plumage when the bird preens itself, leaving its feathers flexible and waterproof. It is also thought to play a role in defending the bird against predators and parasites. We have isolated from the uropygial secretion of a nestling a bacterium that grows in monospecific culture which we have identified unambiguously by phenotypic and genotypic means as Enterococcus faecalis. The strain in question produces antibacterial substances that are active against all gram-positive bacteria assayed and also against some gram-negative strains. Its peptide nature identifies it as a bacteriocin within the group known as enterocins. Two peptides were purified to homogeneity (MR10A and MR10B), and matrix-assisted laser desorption ionization-time of flight (mass spectrometry) analysis showed masses of 5201.58 and 5207.7 Da, respectively. Amino acid sequencing of both peptides revealed high similarity with enterocin L50A and L50B (L. M. Cintas, P. Casaus, H. Holo, P. E. Hernández, I. F. Nes, and L. S. Håvarstein, J. Bacteriol. 180:1988-1994, 1998). PCR amplification of total DNA from strain MRR10-3 with primers for the L50A/B structural genes and sequencing of the amplified fragment revealed almost identical sequences, except for a single conservative change in residue 38 (Glu-->Asp) in MR10A and two changes in residues 9 (Thr-->Ala) and 15 (Leu-->Phe) in MR10B. This is the first time that the production of bacteriocins by a bacterium isolated from the uropygial gland has been described. The production of these broad-spectrum antibacterial substances by an
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Sista, P; Wasikowski, B; Lecocq, P; Pattery, T; Bacheler, L
2008-08-01
The HIV-1 protease mutation I50 L causes atazanavir resistance but increases susceptibility to other PIs. Predicted phenotypic FC values were obtained from viral genotypes, using the virtual Phenotype-LM bioinformatics tool (powering vircoTYPE). To evaluate I50 L's effect on susceptibility to 8 PIs, in a large genotype database. I50 L containing routine clinical isolate samples in Virco's genotype database were paired with samples having like patterns (or profiles) of IAS-USA-defined primary PI mutations, but lacking I50 L. Using vircoTYPE (version 4.1), the median predicted FC for each mutational profile was determined. I50 L-associated shifts in FC were evaluated using drug-specific CCOs. We selected 307 and 37098 samples with and without I50 L. These corresponded to 31 mutation patterns of > or =3 samples each. I50 L caused resistance to atazanavir in all 31 mutation contexts, but was associated with higher susceptibility for other PIs. The largest I50 L-associated shifts in median predicted FC were: 1.2 to 42.4 (atazanavir), 10.2 to 3.2 (amprenavir), 3.3 to 0.5 (darunavir), 13 to 0.5 (indinavir), 34.9 to 1.3 (lopinavir), 22.3 to 1.3 (nelfinavir), 5.2 to 0.3 (saquinavir) and 29.9 to 5.2 (tipranavir). The PI mutation I50 L causes clinically relevant resistance and increased susceptibility to atazanavir and other PIs respectively.
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L X-ray fluorescence cross sections experimentally determined for elements with 45
Energy Technology Data Exchange (ETDEWEB)
Bonzi, Edgardo V., E-mail: bonzie@famaf.unc.edu.ar [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Ciudad Universitaria-5010, Cordoba (Argentina); Badiger, Nagappa M. [Departments of Physics, Karnatak University, Dharwad 580 003, Karnataka (India); Grad, Gabriela B. [Facultad de Matematica, Astronomia y Fisica, Universidad Nacional de Cordoba, Ciudad Universitaria-5010, Cordoba (Argentina); Barrea, Raul A. [The Biophysics Collaborative Access Team (BioCAT), Dept of Biological Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616 (United States); Figueroa, Rodolo G. [Departamento de Cs. Fisicas, Universidad de La Frontera, Temuco (Chile)
2012-04-15
Experimental determination of L fluorescence cross-sections for elements with 45
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Analysis of the effects of 50g/L povidone iodine in conjuncfival sac before cataract surgery
Directory of Open Access Journals (Sweden)
Wen Yang
2013-12-01
Full Text Available AIM: To evaluate the sterilizing effects of 50g/L povidone Iodine used in conjunctival sag before cataract surgery.METHODS: Totally, 58 eyes of 45 cataract patients underwent phacoemulsification aspiration with intraocular lens implantation. The cojunctival sac secretions at three time points(admission, before and after disinfection with povidone iodinewere obtained and then cultured under the same condition and at the same time. The results were observed and identified.RESULTS: At the three points, the positive rate of bacterial culture was 79.3%, 41.9% and 3.4%, respectively. The positive rate significantly reduced gradually. CONCLUSION: The application effect of 50g/L povidone iodine in killing conjunctival sac bacteria is remarkable, which can avoid the postoperative endophthalmitis effectively.
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Abriouel, Hikmate; Lucas, Rosario; Omar, Nabil Ben; Valdivia, Eva; Gálvez, Antonio
2010-06-01
Bacteriocins are antimicrobial peptides produced by bacteria. Among them, the enterococcal bacteriocin (enterocin) AS-48 stands for its peculiar characteristics and broad-spectrum antimicrobial activity. AS-48 belongs to the class of circular bacteriocins and has been studied in depth in several aspects: peptide structure, genetic determinants, and mode of action. Recently, a wealth of knowledge has accumulated on the antibacterial activity of this bacteriocin against foodborne pathogenic and spoilage bacteria in food systems, especially in vegetable foods and drinks. This work provides a general overview on the results from tests carried out with AS-48 in different vegetable food categories (such as fruit juices, ciders, sport and energy drinks, fresh fruits and vegetables, pre-cooked ready to eat foods, canned vegetables, and bakery products). Depending on the food substrate, the bacteriocin has been tested alone or as part of hurdle technology, in combination with physico-chemical treatments (such as mild heat treatments or high-intensity pulsed electric fields) and other antimicrobial substances (such as essential oils, phenolic compounds, and chemical preservatives). Since the work carried out on bacteriocins in preservation of vegetable foods and drinks is much more limited compared to meat and dairy products, the results reported for AS-48 may open new possibilities in the field of bacteriocin applications.
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Lifescience Database Archive (English)
Full Text Available otein, complete cds. 56 0.002 1 AY398693 |AY398693.1 Enterococcus mundtii strain CRL35 enterocin... CRL35 (munA), enterocin CRL 35 ATP-dependent transporter (mun B), and enterocin CRL 35 immun
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Directory of Open Access Journals (Sweden)
Ahmed Khassaf eAL ATYA
2016-05-01
Full Text Available Methicillin-resistant Staphylococcus aureus (MRSA, along with other antibiotic resistant bacteria, has become a worrisome superbug worldwide. This work was aimed at studying the efficacies of two class IIb bacteriocins, enterocins DD28 and DD93, against MRSA-S1 grown in planktonic culture and embedded in biofilms. These bacteriocins were purified, from the cultures supernatants of Enterococcus faecalis 28 and 93, using a simplified purification procedure consisting in a cation exchange chromatography and a reversed-phase high-performance liquid chromatography. The anti-Staphylococcal activity of these bacteriocins was shown in-vitro by the assessment of the minimal inhibitory concentration (MIC. Afterwhich, a checkerboard and time-kill kinetics permitted unveiled a synergistic effect of these bacteriocins in combination with erythromycin and kanamycin against the clinical MRSA-S1. These bacteriocins alone or in combination with erythromycin and kanamycin were able to impede the formation of MRSA-S1 biofilms on stainless steel and glace devices as supported by the microbial cell counts, epifluorescence and Scanning Electron Microscope analyses.
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Basanta Díaz, Antonio
2011-01-01
En este trabajo de investigación se ha procedido al desarrollo y la evaluación de un método de bioconservación de la cerveza basado en la utilización de bacteriocinas producidas por bacterias lácticas (BAL) de origen alimentario como un componente más de un sistema de protección de la calidad en el que se incluyen además diversas “barreras” u “obstáculos” al desarrollo de BAL alterantes de este producto. A este respecto, puede hipotetizarse que la utilización de: (i) bacteriocinas y/o sus mez...
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Energy Technology Data Exchange (ETDEWEB)
Lambrozo, J. [Electricite de France (EDF), 75 - Paris (France); Brugere, H. [Ecole Nationale Veterinaire d`Alfort, 94 - Maison-Alfort (France)
1996-10-01
Since 20 years, studies have been made on the biological effects of 50 / 60 Hz electric and magnetic fields, due to environmental exposure. Two topic have been studied, thanks to rat experimentation. For the first topic: mutagen and reproduction impacts, no obvious effect appeared. For the second one, concerning carcinogen effects for the different organs, a slight tumor promoting effect appeared with magnetic fields for cerebral cortex, and a slightly more significant one for mammary glands. (D.L.)
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Energy Technology Data Exchange (ETDEWEB)
Trad, Henrique Simao; Boasquevisque, Gustavo Santos; Giacometti, Tiago Rangon; Trad, Catherine Yang; Zoghbi Neto, Orlando Salomao; Trad, Clovis Simao, E-mail: hsimtrad@gmail.com [Central de Diagnostico Ribeirao Preto (CEDIRP), Ribeirao Preto, SP (Brazil)
2016-03-15
Objective: To propose a protocol for pulmonary angiography using 64-slice multidetector computed tomography (64-MDCT) with 50 mL of iodinated contrast material, in an unselected patient population, as well as to evaluate vascular enhancement and image quality. Materials and methods: We evaluated 29 patients (22-86 years of age). The body mass index ranged from 19.0 kg/m{sup 2} to 41.8 kg/m{sup 2}. Patients underwent pulmonary CT angiography in a 64-MDCT scanner, receiving 50 mL of iodinated contrast material via venous access at a rate of 4.5 mL/s. Bolus tracking was applied in the superior vena cava. Two experienced radiologists assessed image quality and vascular enhancement. Results: The mean density was 382 Hounsfield units (HU) for the pulmonary trunk; 379 and 377 HU for the right and left main pulmonary arteries, respectively; and 346 and 364 HU for the right and left inferior pulmonary arteries, respectively. In all patients, subsegmental arteries were analyzed. There were streak artifacts from contrast material in the superior vena cava in all patients. However, those artifacts did not impair the image analysis. Conclusion: Our findings suggest that pulmonary angiography using 64-MDCT with 50 mL of iodinated contrast can produce high quality images in unselected patient populations. (author)
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PLGA 50:50 nanoparticles of paclitaxel: Development, in vitro anti ...
Indian Academy of Sciences (India)
lation of novel drug delivery systems to deliver such extreme hydrophobic drug. ... drug delivery system for PTX using biodegradable PLGA. 50:50 .... To this, 200 μl of protein precipitat- ..... Murthy R R 2004 The AAPS Journal 6 Article 23.
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Perez, Rodney H; Sugino, Haruki; Ishibashi, Naoki; Zendo, Takeshi; Wilaipun, Pongtep; Leelawatcharamas, Vichien; Nakayama, Jiro; Sonomoto, Kenji
2017-04-01
Enterocin NKR-5-3B (Ent53B) is a 64-residue novel circular bacteriocin synthesized from an 87-residue prepeptide. Albeit through a still unknown mechanism, the EnkB1234 biosynthetic enzyme complex processes the prepeptide to yield its mature active, circular form. To gain insights into the key region/residue that plays a role in Ent53 maturation, several mutations near the cleavage site on the precursor peptide were generated. The interaction of the precursor peptide and EnkB1234 appeared to be hydrophobic in nature. At the Leu1 position, only mutations with helix structure-promoting hydrophobic residues (Ala, Ile, Val or Phe) were able to yield the mature Ent53B derivative. In this study, we also highlight the possible conformation-stabilizing role of the Ent53B leader peptide on the precursor peptide for its interaction with its biosynthetic enzyme complex. Any truncations of the leader peptide moiety interfered in the processing of the prepeptide. However, when propeptides of other circular bacteriocins (circularin A, leucocyclicin Q or lactocyclicin Q) were cloned at the C-terminus of the leader peptide, EnkB1234 could not process them to yield a mature bacteriocin. Taken together, these findings offer new perspectives in our understanding of the possible molecular mechanism of the biosynthesis of this circular bacteriocin. These new perspectives will help advance our current understanding to eventually elucidate circular bacteriocin biosynthesis. Understanding the biosynthetic mechanism of circular bacteriocins will materialize their application potential.
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Ananou, S; Zentar, H; Martínez-Bueno, M; Gálvez, A; Maqueda, M; Valdivia, E
2014-12-01
The purpose of this study was to determine the effect of enterocin AS-48, packaged under normal atmosphere (NA), vacuum (VP) or modified atmosphere (MAP) on the shelf life and safety of fresh sardines (Sardina pilchardus) stored at 5 °C. We studied the effect of these hurdles, alone or combined, on the relevant autochthonous bacterial populations. Total volatile basic nitrogen (TVB-N) content was used as indicative of freshness. Levels of biogenic amines cadaverine, putrescine, tyramine, and histamine were also determined. The application of AS-48 did not reduce the mesophilic, psychrotrophic, or Gram negative bacteria viable cell counts under any of the storage conditions tested. AS-48 did cause significant reductions in viable staphylococci counts, especially under VP. In sardines under NA treated with AS-48, the populations of histamine- and tyramine-forming total and lactic acid bacteria (LAB) showed no significant reductions. MAP or VP with AS-48 allowed reductions (significant at some storage times) in histamine- and tyramine-forming LAB. The TVB-N content was also reduced under normal atmosphere and, especially, in sardines stored under MAP. The most interesting results are those concerning the decrease (by several fold) in the levels of the biogenic amines cadaverine, putrescine, tyramine, and histamine determined after treatment with AS-48. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Validation of a chromatographic method for quantitation of 50 μg/mL Latanoprost in a Cuban eye drops
International Nuclear Information System (INIS)
Garcia Penna, Caridad Margarita; Martinez Espinosa, Vivian; Gonzalez Cortezon, Ania
2012-01-01
Latanoprost is indicated to treat high intraocular pressure in patients suffering from ocular hypertension or from open angle glaucoma. To develop and to validate a high performance liquid chromatography-based analytical method for quality control of 50 μg/mL Latanoprost eye drops
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Martínez-Viedma, Pilar; Abriouel, Hikmate; Omar, Nabil Ben; Valdivia, Eva; López, Rosario Lucas; Gálvez, Antonio
2008-03-01
The bacteriocin enterocin AS-48 was tested against exopolysaccharide producing lactic acid bacteria (LAB) strains of Lactobacillus collinoides, Lactobacillus dioliovorans and Pediococcus parvulus as well as two 3-hydroxypropionaldehyde (3-HPA)-producing Lb. collinoides strains causing apple cider spoilage. In fresh-made apple juice, a bacteriocin concentration of 2.5 microg/ml reduced the LAB viable cell counts below detection levels during the course of incubation at 10 and 22 degrees C for most strains tested, except for Lb. collinoides 5 and Lb. dioliovorans 29. These two strains were significantly inhibited at 10 degrees C by 5 microg/ml AS-48 or completely inactivated at 22 degrees C. In a commercial Basque apple cider, the added bacteriocin (2.5 microg/ml for Lb. collinoides strains 9 and 10, and 5 microg/ml for the rest of strains) completely inactivated all LAB strains tested during storage at 10 as well as 22 degrees C. In the commercial Asturian apple cider tested the LAB strains showed a poor capacity for survival, but the added bacteriocin was equally effective in reducing the numbers of survivors. When a cocktail of the five LAB strains was tested in commercial Basque apple cider, viable cell counts were reduced below detection levels after 2 days for a bacteriocin concentration of 12.5 microg/ml regardless of storage temperature. Comparison of RAPD-PCR profiles revealed that strain Lb. dioliovorans 29 was always the predominant survivor detected in bacteriocin-treated samples.
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Khan, Mohammad Ahad Ali; Islam, Mohammad Torequl
2012-04-01
The aim of the study was to evaluate analgesic and cytotoxic activity of Acorus calamus L., Kigelia pinnata L., Mangifera indica L., Tabernaemontana divaricata L. extracts by using acetic acid-induced writhing method in mice and brine shrimp lethality assay. The ethanolic extracts of the plants were obtained by simple maceration method and were subjected to standardization by using pharmacognostical and phytochemical screening methods, which were followed by acetic acid writhing and brine shrimp lethality test methods. Dose selection was made on the basis of acute oral toxicity study (10-1000 mg/kg body weight). In analgesic test, M. indica L. extract produced 28.16% and 22.02% writhing protection at the doses of 250 and 500 mg/kg body weight in mice, respectively. While the T. divaricata L. extract produced 22.02% and 33.93%, K. pinnata L. extract produced 11.55% and 47.29% and A. calamus L. extract produced 15.16% and 54.51% of writhing protection at the same doses. The percent mortality (mean ± SD) was found to be 58.7 ± 25.22, 56.25 ± 22.88, 52.50 ± 24.37, and 61.25 ± 26.66 with M. indica L., T. divaricata L., K. pinnata L., and A. calamus L., respectively. And the LC(50) and LC(90) values were found to be 100 and 300 μg/mL for M. indica L. and that were (200 and 350 μg/mL), (100 and 350 μg/mL) and (50 and 300 μg/mL) for T. divaricata L., K. pinnata L., and A. calamus L., respectively. Thus it can be concluded that bark of M. indica L., leaves of T. divaricata L., bark of K. pinnata L., and roots of A. calamus L. have significant analgesic and cytotoxic activity and can be preferred in the treatment of pain and tumor.
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Directory of Open Access Journals (Sweden)
Mohammad Ahad Ali Khan
2012-01-01
Full Text Available Objectives: The aim of the study was to evaluate analgesic and cytotoxic activity of Acorus calamus L., Kigelia pinnata L., Mangifera indica L., Tabernaemontana divaricata L. extracts by using acetic acid-induced writhing method in mice and brine shrimp lethality assay. Materials and Methods: The ethanolic extracts of the plants were obtained by simple maceration method and were subjected to standardization by using pharmacognostical and phytochemical screening methods, which were followed by acetic acid writhing and brine shrimp lethality test methods. Dose selection was made on the basis of acute oral toxicity study (10-1000 mg/kg body weight. Results and Conclusion: In analgesic test, M. indica L. extract produced 28.16% and 22.02% writhing protection at the doses of 250 and 500 mg/kg body weight in mice, respectively. While the T. divaricata L. extract produced 22.02% and 33.93%, K. pinnata L. extract produced 11.55% and 47.29% and A. calamus L. extract produced 15.16% and 54.51% of writhing protection at the same doses. The percent mortality (mean ± SD was found to be 58.7 ± 25.22, 56.25 ± 22.88, 52.50 ± 24.37, and 61.25 ± 26.66 with M. indica L., T. divaricata L., K. pinnata L., and A. calamus L., respectively. And the LC 50 and LC 90 values were found to be 100 and 300 μg/mL for M. indica L. and that were (200 and 350 μg/mL, (100 and 350 μg/mL and (50 and 300 μg/mL for T. divaricata L., K. pinnata L., and A. calamus L., respectively. Thus it can be concluded that bark of M. indica L., leaves of T. divaricata L., bark of K. pinnata L., and roots of A. calamus L. have significant analgesic and cytotoxic activity and can be preferred in the treatment of pain and tumor.
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Energy Technology Data Exchange (ETDEWEB)
Arora, S K; Allawadhi, K L; Sood, B S [Punjabi Univ., Patiala (India). Nuclear Science Labs.
1980-08-28
The energy dependence of L-shell photoelectric cross sections for lead in the energy region 17-50 keV has been investigated. The method utilises external conversion x-rays as the source of photons and it yields relative rather than absolute cross sections, but is simpler and more accurate. The results show fairly good agreement with theory.
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Bergmann, U; Wittmann-Liebold, B
1993-03-23
50S ribosomal subunits from the extreme halophilic archaebacterium Haloarcula marismortui were treated with the homobifunctional protein-protein cross-linking reagents diepoxybutane (4 A) and dithiobis(succinimidyl propionate) (12 A). The dominant product with both cross-linking reagents was identified on the protein level as HmaL23-HmaL29, which is homologous to the protein pair L23-L29 from Escherichia coli [Walleczek, J., Martin, T., Redl, B., Stöffler-Meilicke, M., & Stöffler, G. (1989) Biochemistry 28, 4099-4105] and from Bacillus stearothermophilus [Brockmöller, J., & Kamp, R. M. (1986) Biol. Chem. Hoppe-Seyler 367, 925-935]. To reveal the exact cross-linking site in HmaL23-HmaL29, the cross-linked complex was purified on a preparative scale by conventional and high-performance liquid chromatography. After endoproteolytic fragmentation of the protein pair, the amino acids engaged in cross-link formation were unambiguously identified by N-terminal sequence analysis and mass spectrometry of the cross-linked peptides. The cross-link is formed between lysine-57 in the C-terminal region of HmaL29 and the alpha-amino group of the N-terminal serine in protein HmaL23, irrespective of the cross-linking reagent. This result demonstrates that the N-terminal region of protein HmaL23 and the C-terminal domain of HmaL29 are highly flexible so that the distance between the two polypeptide chains can vary by at least 8 A. Comparison of our cross-linking results with those obtained with B. stearothermophilus revealed that the fine structure within this ribosomal domain is at least partially conserved.
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Le CERN reçoit à l'avance un cadeau de la Confédération suisse pour son 50e anniversaire
CERN Press Office. Geneva
2003-01-01
Swiss President Pascal Couchepin announced an early 50th birthday present from the Swiss Confederation to CERN. Switzerland has decided to offer the laboratory the 'Palais de l'Equilibre', a landmark building designed by Geneva architects for Switzerland's 2002 national exhibition.
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Directory of Open Access Journals (Sweden)
Chris Henning
2015-02-01
Full Text Available Twenty-two bacteriocin-producing Enterococcus isolates obtained from food and animal sources, and demonstrating activity against Listeria monocytogenes, were screened for bacteriocin-related genes using a bacteriocin PCR array based on known enterococcal bacteriocin gene sequences in the NCBI GenBank database. The 22 bacteriocin-positive (Bac+ enterococci included En. durans (1, En. faecalis (4, En. faecium (12, En. hirae (3, and En. thailandicus (2. Enterocin A (entA, enterocins mr10A and mr10B (mr10AB, and bacteriocin T8 (bacA were the most commonly found structural genes in order of decreasing prevalence. Forty-five bacteriocin genes were identified within the 22 Bac+ isolates, each containing at least one of the screened structural genes. Of the 22 Bac+ isolates, 15 possessed two bacteriocin genes, seven isolates contained three different bacteriocins, and three isolates contained as many as four different bacteriocin genes. These results may explain the high degree of bactericidal activity observed with various Bac+ Enterococcus spp. Antimicrobial activity against wild-type L. monocytogenes and a bacteriocin-resistant variant demonstrated bacteriocins having different modes-of-action. Mixtures of bacteriocins, especially those with different modes-of-action and having activity against foodborne pathogens, such as L. monocytogenes, may play a promising role in the preservation of food.
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Microwave reflection properties of planar anisotropy Fe50Ni50 powder/paraffin composites
International Nuclear Information System (INIS)
Wei Jian-Qiang; Zhang Zhao-Qi; Han Rui; Wang Tao; Li Fa-Shen
2012-01-01
The reflection properties of planar anisotropy Fe 50 Ni 50 powder/paraffin composites have been studied in the microwave frequency range. The permeability of Fe 50 Ni 50 powder/paraffin composites is greatly enhanced by introducing the planar anisotropy, and can be further enhanced by using a rotational orientation method. The complex permeability can be considered as the superposition of two types of magnetic resonance. The resonance peak at high frequency is attributed to the natural resonance, while the peak at low frequency is attributed to the domain-wall resonance. The simulated results of the microwave reflectivity show that the matching thickness, peak frequency, permeability, and permittivity are closely related to the quarter wavelength matching condition. The Fe 50 Ni 50 powder/paraffin composites can be attractive candidates for thinner microwave absorbers in the L-band (1–2 GHz). (condensed matter: electronic structure, electrical, magnetic, and optical properties)
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2010-10-01
... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Authority. 50.101-1... EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 50.101-1 Authority. (a... following agencies to exercise the authority conferred by Pub. L. 85-804 and to delegate it to other...
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Fault-Tolerant Consensus of Multi-Agent System With Distributed Adaptive Protocol.
Chen, Shun; Ho, Daniel W C; Li, Lulu; Liu, Ming
2015-10-01
In this paper, fault-tolerant consensus in multi-agent system using distributed adaptive protocol is investigated. Firstly, distributed adaptive online updating strategies for some parameters are proposed based on local information of the network structure. Then, under the online updating parameters, a distributed adaptive protocol is developed to compensate the fault effects and the uncertainty effects in the leaderless multi-agent system. Based on the local state information of neighboring agents, a distributed updating protocol gain is developed which leads to a fully distributed continuous adaptive fault-tolerant consensus protocol design for the leaderless multi-agent system. Furthermore, a distributed fault-tolerant leader-follower consensus protocol for multi-agent system is constructed by the proposed adaptive method. Finally, a simulation example is given to illustrate the effectiveness of the theoretical analysis.
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Perez, Rodney H; Ishibashi, Naoki; Inoue, Tomoko; Himeno, Kohei; Masuda, Yoshimitsu; Sawa, Narukiko; Zendo, Takeshi; Wilaipun, Pongtep; Leelawatcharamas, Vichien; Nakayama, Jiro; Sonomoto, Kenji
2016-01-15
A putative biosynthetic gene cluster of the enterocin NKR-5-3B (Ent53B), a novel circular bacteriocin, was analyzed by sequencing the flanking regions around enkB, the Ent53B structural gene, using a fosmid library. A region approximately 9 kb in length was obtained, and the enkB1, enkB2, enkB3, and enkB4 genes, encoding putative biosynthetic proteins involved in the production, maturation, and secretion of Ent53B, were identified. We also determined the identity of proteins mediating self-immunity against the effects of Ent53B. Heterologous expression systems in various heterologous hosts, such as Enterococcus faecalis and Lactococcus lactis strains, were successfully established. The production and secretion of the mature Ent53B required the cooperative functions of five genes. Ent53B was produced only by those heterologous hosts that expressed protein products of the enkB, enkB1, enkB2, enkB3, and enkB4 genes. Moreover, self-immunity against the antimicrobial action of Ent53B was conferred by at least two independent mechanisms. Heterologous hosts harboring the intact enkB4 gene and/or a combination of intact enkB1 and enkB3 genes were immune to the inhibitory action of Ent53B. In addition to their potential application as food preservatives, circular bacteriocins are now considered possible alternatives to therapeutic antibiotics due to the exceptional stability conferred by their circular structure. The successful practical application of circular bacteriocins will become possible only if the molecular details of their biosynthesis are fully understood. The results of the present study offer a new perspective on the possible mechanism of circular bacteriocin biosynthesis. In addition, since some enterococcal strains are associated with pathogenicity, virulence, and drug resistance, the establishment of the first multigenus host heterologous production of Ent53B has very high practical significance, as it widens the scope of possible Ent53B applications
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Directory of Open Access Journals (Sweden)
Koffi Koba
2009-06-01
Full Text Available The leaf essential oils of Cymbopogon citratus L. and Cymbopogon nardus L.(Poaceae from Togo were steam-distilled, analyzed for percentage composition and investigated in vitro for their potential cytotoxic activity on human epidermic cell line HaCat. The percentage composition showed that the main constituents of essential oils samples were respectively geranial (45.2%, neral(32.4% and myrcène (10.2% for C. citratus essential oil and citronellal (35.5%, geraniol (27.9% and citronellol (10.7% for that of C. nardus. The in vitro cytotoxicity bioassays on human epidermic cell line HaCaT revealed that the toxicityof the essential oil from C. citratus (IC50: 150 μL.mL-1 was higher than that of the essential oil from C. nardus (IC50: 450 μL.mL-1. Pure commercial neral, geranial, and citronellal standards showed respectively the following IC50 values: 100, 250 and 300 μL.mL-1. Conversely, pure citronellol standard appeared almost non-toxic (IC50>1000 μL.mL-1, proving the major role played in synergyby neral and geranial in the overall toxicity showed by the citratus oil sample tested in this work.
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Directory of Open Access Journals (Sweden)
Koffi Koba
2009-03-01
Full Text Available The leaf essential oils of Cymbopogon citratus L. and Cymbopogon nardus L. (Poaceae from Togo were steam-distilled, analyzed for percentage composition and investigated in vitro for their potential cytotoxic activity on human epidermic cell line HaCat. The percentage composition showed that the main constituents of essential oils samples were respectively geranial (45.2%, neral (32.4% and myrc¨ne (10.2% for C. citratus essential oil and citronellal (35.5%, geraniol (27.9% and citronellol (10.7% for that of C. nardus. The in vitro cytotoxicity bioassays on human epidermic cell line HaCaT revealed that the toxicity of the essential oil from C. citratus (IC50: 150 µL.mL-1 was higher than that of the essential oil from C. nardus (IC50: 450 µL.mL-1. Pure commercial neral, geranial, and citronellal standards showed respectively the following IC50 values: 100, 250 and 300 µL.mL-1. Conversely, pure citronellol standard appeared almost non-toxic (IC50>1000 µL.mL-1, proving the major role played in synergy by neral and geranial in the overall toxicity showed by the citratus oil sample tested in this work.
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Lee, You-Jeong; Kim, Chung-Hoon; Kwack, Jae-Young; Ahn, Jun-Woo; Kim, Sung-Hoon; Chae, Hee-Dong; Kang, Byung-Moon
2014-11-01
To investigate the prevalence of subclinical hypothyroidism (SH) diagnosed by thyrotropin-releasing hormone (TRH) stimulating test in infertile women with basal thyroid-stimulating hormone (TSH) levels of 2.5 to 5.0 mIU/L. This study was performed in 39 infertile women with ovulatory disorders (group 1) and 27 infertile women with male infertility only (group 2, controls) who had basal serum TSH levels of 2.5 to 5.0 mIU/L and a TRH stimulating test. Serum TSH levels were measured before TRH injection (TSH0) and also measured at 20 minutes (TSH1) and 40 minutes (TSH2) following intravenous injection of 400 µg TRH. Exaggerated TSH response above 30 mIU/L following TRH injection was diagnosed as SH. Group 1 was composed of poor responders (subgroup A), patients with polycystic ovary syndrome (subgroup B) and patients with WHO group II anovulation except poor responder or polycystic ovary syndrome (subgroup C). The prevalence of SH was significantly higher in group 1 of 46.2% (18/39) compared with 7.4% (2/27) in group 2 (P=0.001). TSH0, TSH1, and TSH2 levels were significantly higher in group 1 than the corresponding values in group 2 (Pstimulation test had better be performed in infertile women with ovulatory disorders who have TSH levels between 2.5 and 5.0 mIU/L for early detection and appropriate treatment of SH.
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Vimont, Allison; Fernandez, Benoît; Hammami, Riadh; Ababsa, Ahlem; Daba, Hocine; Fliss, Ismaïl
2017-01-01
Bacterial isolates from raw camel milk were screened for antibacterial activity using the agar diffusion assay. Ten isolates selected for their inhibition of Gram-positive bacteria were identified by 16S sequencing as Enterococcus faecium or durans . An isolate named E. faecium LCW 44 exhibited the broadest antibacterial spectrum with an inhibitory activity against several Gram-positive strains belonging to the genera Clostridium , Listeria , Staphylococcus , and Lactobacillus. E. faecium LCW 44 was shown to produce N-formylated enterocins L50A and L50B, as revealed by mass spectrometry and PCR analyses. This isolate did not harbor any of the virulence factors tested and was shown to be sensitive to all tested antibiotics. It showed high resistance to gastric and intestinal conditions (78 ± 4% survival). Its adhesion index was evaluated at 176 ± 86 and 24 ± 86 on Caco-2 cells and HT-29 cells, respectively, and it significantly reduced adhesion of Listeria monocytogenes by 65 and 49%, respectively. In Macfarlane broth (simulating the nutrient content of the colon), counts of L. monocytogenes were reduced by 2 log 10 cycles after 24 h in co-culture with E. faecium LCW 44, compared to the increase of 4 log 10 cycles when cultured alone. Comparison with a bacteriocin-non-producing mutant of E. faecium LCW 44 strongly suggests that inhibition of L. monocytogenes was due to bacteriocin production. Altogether, E. faecium LCW 44 thus has potential for use as a probiotic for humans and veterinary medicine.
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Directory of Open Access Journals (Sweden)
Allison Vimont
2017-05-01
Full Text Available Bacterial isolates from raw camel milk were screened for antibacterial activity using the agar diffusion assay. Ten isolates selected for their inhibition of Gram-positive bacteria were identified by 16S sequencing as Enterococcus faecium or durans. An isolate named E. faecium LCW 44 exhibited the broadest antibacterial spectrum with an inhibitory activity against several Gram-positive strains belonging to the genera Clostridium, Listeria, Staphylococcus, and Lactobacillus. E. faecium LCW 44 was shown to produce N-formylated enterocins L50A and L50B, as revealed by mass spectrometry and PCR analyses. This isolate did not harbor any of the virulence factors tested and was shown to be sensitive to all tested antibiotics. It showed high resistance to gastric and intestinal conditions (78 ± 4% survival. Its adhesion index was evaluated at 176 ± 86 and 24 ± 86 on Caco-2 cells and HT-29 cells, respectively, and it significantly reduced adhesion of Listeria monocytogenes by 65 and 49%, respectively. In Macfarlane broth (simulating the nutrient content of the colon, counts of L. monocytogenes were reduced by 2 log10 cycles after 24 h in co-culture with E. faecium LCW 44, compared to the increase of 4 log10 cycles when cultured alone. Comparison with a bacteriocin-non-producing mutant of E. faecium LCW 44 strongly suggests that inhibition of L. monocytogenes was due to bacteriocin production. Altogether, E. faecium LCW 44 thus has potential for use as a probiotic for humans and veterinary medicine.
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Doshi, Ankita; Sharma, Mrinal; Prabha, C Ratna
2017-06-01
Posttranslational conjugation of ubiquitin to proteins either regulates their function directly or concentration through ubiquitination dependent degradation. High degree of conservation of ubiquitin's sequence implies structural and functional importance of the conserved residues. Ubiquitin gene of Saccharomyces cerevisiae was evolved in vitro by us to study the significance of conserved residues. Present study investigates the structural changes in the protein resulting from the single mutations UbS20F, UbA46S, UbL50P, UbI61T and their functional consequences in the SUB60 strain of S. cerevisiae. Expression of UbL50P and UbI61T decreased Cdc28 protein kinase, enhanced Fus3 levels, caused dosage dependent lethality and at sublethal level produced drastic effects on stress tolerance, protein sorting, protein degradation by ubiquitin fusion degradation pathway and by lysosomes. UbS20F and UbA46S produced insignificant effects over the cells. All four mutations of ubiquitin were incorporated into polyubiquitin. However, polyubiquitination with K63 linkage decreased significantly in cells expressing UbL50P and UbI61T. Structural studies on UbL50P and UbI61T revealed distorted structure with greatly reduced α-helical and elevated β-sheet contents, while UbS20F and UbA46S show mild structural alterations. Our results on functional efficacy of ubiquitin in relation to structural integrity may be useful for designing inhibitors to investigate and modulate eukaryotic cellular dynamics. Copyright © 2017 Elsevier B.V. All rights reserved.
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Vasilchenko, A S; Vasilchenko, A V; Valyshev, A V; Rogozhin, E A
2018-02-08
Discovery of a novel bacteriocin is always an event in sciences, since cultivation of most bacterial species is a general problem in microbiology. This statement is reflected by the fact that number of bacteriocins is smaller for tenfold comparing to known antimicrobial peptides. We cultivated Enterococcus faecium on simplified medium to reduce amount of purification steps. This approach allows to purify the novel heavy weight bacteriocin produced by E. faecium ICIS 7. The novelty of this bacteriocin, named enterocin-7, was confirmed by N-terminal sequencing and by comparing the structural-functional properties with available data. Purified enterocin-7 is characterized by a sequence of amino acid residues having no homology in UniProt/SwissProt/TrEMBL databases: NH2 - Asp - Ala - His - Leu - Ser - Glu - Val - Ala - Glu - Arg - Phe - Glu - Asp - Leu - Gly. Isolated thermostable protein has a molecular mass of 65 kDa, which allows it to be classified into class III in bacteriocin classification schemes. Enterocin-7 displayed a broad spectrum of activity against some Gram-positive and Gram-negative microorganisms. Fluorescent microscopy and spectroscopy showed the permeabilizing mechanism of the action of enterocin-7, which is realized within a few minutes.
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Kumari, Sanju; M Sheba, Jennifer; Marappan, Maheshwaran; Ponnuswamy, Shanmugasunderam; Seetharaman, Suresh; Pothi, Nagarajan; Subbarayalu, Mohankumar; Muthurajan, Raveendran; Natesan, Senthil
2010-09-01
Brown planthopper (Nilaparvata lugens Stål) is one of the major insect pests of rice. A Sri Lankan indica rice cultivar Rathu Heenati was found to be resistant to all biotypes of the brown planthopper. In the present study, a total of 268 F(7) RILs of IR50 and Rathu Heenati were phenotyped for their level of resistance against BPH by the standard seedbox screening test (SSST) in the greenhouse. A total of 53 SSR primers mapped on the chromosome 3 were used to screen the polymorphism between the parents IR50 and Rathu Heenati, out of which eleven were found to be polymorphic between IR50 and Rathu Heenati. The eleven primers that have shown polymorphism between the IR50 and Rathu Heenati parents were genotyped in a set of five resistant RILs and five susceptible RILs along with the parents for co-segregation analysis. Among the eleven primers, two primers namely RM3180 (18.22 Mb) and RM2453 (20.19 Mb) showed complete co-segregation with resistance. The identification of SSR markers linked with BPH resistant could be used for the maker assisted selection (MAS) program in rice breeding and to map the resistant genes on rice chromosomes for further gene cloning.
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Assoumou, L; Charpentier, C; Recordon-Pinson, P; Grudé, M; Pallier, C; Morand-Joubert, L; Fafi-Kremer, S; Krivine, A; Montes, B; Ferré, V; Bouvier-Alias, M; Plantier, J-C; Izopet, J; Trabaud, M-A; Yerly, S; Dufayard, J; Alloui, C; Courdavault, L; Le Guillou-Guillemette, H; Maillard, A; Amiel, C; Vabret, A; Roussel, C; Vallet, S; Guinard, J; Mirand, A; Beby-Defaux, A; Barin, F; Allardet-Servent, A; Ait-Namane, R; Wirden, M; Delaugerre, C; Calvez, V; Chaix, M-L; Descamps, D; Reigadas, S
2017-06-01
Surveillance of HIV-1 resistance in treated patients with a detectable viral load (VL) is important to monitor, in order to assess the risk of spread of resistant viruses and to determine the proportion of patients who need new antiretroviral drugs with minimal cross-resistance. The HIV-1 protease and reverse transcriptase (RT) and integrase genes were sequenced in plasma samples from 782 consecutive patients on failing antiretroviral regimens, seen in 37 specialized centres in 2014. The genotyping results were interpreted using the ANRS v24 algorithm. Prevalence rates were compared with those obtained during a similar survey conducted in 2009. The protease and RT sequences were obtained in 566 patients, and the integrase sequence in 382 patients. Sequencing was successful in 60%, 78%, 78% and 87% of patients with VLs of 51-200, 201-500, 501-1000 and >1000 copies/mL, respectively. Resistance to at least one antiretroviral drug was detected in 56.3% of samples. Respectively, 3.9%, 8.7%, 1.5% and 3.4% of patients harboured viruses that were resistant to any NRTI, NNRTI, PI and integrase inhibitor (INI). Resistance rates were lower in 2014 than in 2009. Resistance was detected in 48.5% of samples from patients with a VL between 51 and 200 copies/mL. In France in 2014, 90.0% of patients in AIDS care centres were receiving antiretroviral drugs and 12.0% of them had VLs >50 copies/mL. Therefore, this study suggests that 6.7% of treated patients in France might transmit resistant strains. Resistance testing may be warranted in all treated patients with VL > 50 copies/mL. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Directory of Open Access Journals (Sweden)
Letícia de C. Oliveira
2017-05-01
Full Text Available A bacteriocinogenic Lactobacillus rhamnosus L156.4 strain isolated from the feces of NIH mice was identified by 16S rRNA gene sequencing and MALDI-TOF mass spectrometry. The entire genome was sequenced using Illumina, annotated in the PGAAP, and RAST servers, and deposited. Conserved genes associated with bacteriocin synthesis were predicted using BAGEL3, leading to the identification of an open reading frame (ORF that shows homology with the L. rhamnosus GG (ATCC 53103 prebacteriocin gene. The encoded protein contains a conserved protein motif associated a structural gene of the Enterocin A superfamily. We found ORFs related to the prebacteriocin, immunity protein, ABC transporter proteins, and regulatory genes with 100% identity to those of L. rhamnosus HN001. In this study, we provide evidence of a putative bacteriocin produced by L. rhamnosus L156.4 that was further confirmed by in vitro assays. The antibacterial activity of the substances produced by this strain was evaluated using the deferred agar-spot and spot-on-the lawn assays, and a wide antimicrobial activity spectrum against human and foodborne pathogens was observed. The physicochemical characterization of the putative bacteriocin indicated that it was sensitive to proteolytic enzymes, heat stable and maintained its antibacterial activity in a pH ranging from 3 to 9. The activity against Lactobacillus fermentum, which was used as an indicator strain, was detected during bacterial logarithmic growth phase, and a positive correlation was confirmed between bacterial growth and production of the putative bacteriocin. After a partial purification from cell-free supernatant by salt precipitation, the putative bacteriocin migrated as a diffuse band of approximately 1.0–3.0 kDa by SDS-PAGE. Additional studies are being conducted to explore its use in the food industry for controlling bacterial growth and for probiotic applications.
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Oliveira, Letícia de C.; Silveira, Aline M. M.; Monteiro, Andréa de S.; dos Santos, Vera L.; Nicoli, Jacques R.; Azevedo, Vasco A. de C.; Soares, Siomar de C.; Dias-Souza, Marcus V.; Nardi, Regina M. D.
2017-01-01
A bacteriocinogenic Lactobacillus rhamnosus L156.4 strain isolated from the feces of NIH mice was identified by 16S rRNA gene sequencing and MALDI-TOF mass spectrometry. The entire genome was sequenced using Illumina, annotated in the PGAAP, and RAST servers, and deposited. Conserved genes associated with bacteriocin synthesis were predicted using BAGEL3, leading to the identification of an open reading frame (ORF) that shows homology with the L. rhamnosus GG (ATCC 53103) prebacteriocin gene. The encoded protein contains a conserved protein motif associated a structural gene of the Enterocin A superfamily. We found ORFs related to the prebacteriocin, immunity protein, ABC transporter proteins, and regulatory genes with 100% identity to those of L. rhamnosus HN001. In this study, we provide evidence of a putative bacteriocin produced by L. rhamnosus L156.4 that was further confirmed by in vitro assays. The antibacterial activity of the substances produced by this strain was evaluated using the deferred agar-spot and spot-on-the lawn assays, and a wide antimicrobial activity spectrum against human and foodborne pathogens was observed. The physicochemical characterization of the putative bacteriocin indicated that it was sensitive to proteolytic enzymes, heat stable and maintained its antibacterial activity in a pH ranging from 3 to 9. The activity against Lactobacillus fermentum, which was used as an indicator strain, was detected during bacterial logarithmic growth phase, and a positive correlation was confirmed between bacterial growth and production of the putative bacteriocin. After a partial purification from cell-free supernatant by salt precipitation, the putative bacteriocin migrated as a diffuse band of approximately 1.0–3.0 kDa by SDS-PAGE. Additional studies are being conducted to explore its use in the food industry for controlling bacterial growth and for probiotic applications. PMID:28579977
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Outcomes of childhood asthma to the age of 50 years.
Tai, Andrew; Tran, Haily; Roberts, Mary; Clarke, Nadeene; Gibson, Anne-Marie; Vidmar, Suzanna; Wilson, John; Robertson, Colin F
2014-06-01
In 1964, The Melbourne Asthma Study was established to describe the spectrum and natural history of childhood asthma. To describe the clinical and lung function outcome of childhood asthma to the age of 50 years. Subjects were invited to complete an interviewer-administered questionnaire, skin prick testing, and measurement of lung function from the age of 7 years to the age of 50 years at 7-year intervals. Of 458 survivors (from the original 484 subjects at recruitment), 346 subjects (76%) participated, of whom, 197 completed lung function measurement. Asthma remission at the age of 50 years was 64% in those with wheezy bronchitis, 47% for those with persistent asthma, and 15% for those with severe asthma in childhood. Multivariable analysis identified severe asthma in childhood (odds ratio [OR] 11.9 [95% CI, 3.4-41.8]), female sex (OR 2.0 [95% CI, 1.1-3.6]), and childhood hay fever (OR 2.0 [95% CI, 1.0-4.0]) as risk factors for "current asthma" at age 50 years. There was no evidence of a difference in the rate of decline in FEV1 (mL/y, 95% CI) between the severe asthma group (15 mL/y [95% CI, 9-22 mL/y]) and all the other recruitment groups: control (16 mL/y [95% CI, 12-20 mL/y]), mild wheezy bronchitis (14 mL/y [95% CI, 8-19 mL/y]), wheezy bronchitis (16 mL/y [95% CI, 11-20 mL/y]), and persistent asthma (19 mL/y [95% CI, 13-24 mL/y]). The clinical and lung function outcome in adult life is strongly determined by asthma severity in childhood. The reduced lung function seen in adults is established in childhood and does not appear to decline more rapidly in adult years despite continuing symptoms. Copyright © 2014 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.
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Directory of Open Access Journals (Sweden)
YOUSEF eNAMI
2015-07-01
Full Text Available AbstractScreening of lactic acid bacteria isolated from ewe colostrum led to the identification and isolation of Enterococcus faecium CM33 with interesting features, such as high-survival rates under acidic or bile salt conditions, high tolerance to the simulated gastrointestinal condition, and high adhesive potential to Caco-2 cells. According to the inhibition of pathogen adhesion test results, this strain could reduce more than 50% adhesion capacity of Escherichia coli, Shigella flexneri, Klebsiella pneumoniae, Listeria monocytogenes, and Staphylococcus aureus to Caco-2 cells. Based on the antibiotic sensitivity test findings, E. faecium CM33 was susceptible to gentamycin, vancomycin, erythromycin, ampicillin, penicillin, tetracycline, and rifampicin, but resistant to chloramphenicol, clindamycin, and kanamycin. Upon the assessment of the virulence determinants for E. faecium CM33, this strain was negative for all tested virulence genes. Furthermore, the genome of this strain was evaluated for the incidence of the known enterocin genes by specific PCR amplification, and the genes encoding enterocins A, 31, X, and Q were discovered. The findings of this study showed that the strain E. faecium CM33 could be considered a valuable nutraceutical, and it can be introduced as a new potential probiotic.
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Chang, Chenchen; Huang, Rong; Yan, Yan; Ma, Hongmin; Dai, Zheng; Zhang, Benying; Deng, Zixin; Liu, Wen; Qu, Xudong
2015-04-01
Selective modification of carbon scaffolds via biosynthetic engineering is important for polyketide structural diversification. Yet, this scope is currently restricted to simple aliphatic groups due to (1) limited variety of CoA-linked extender units, which lack aromatic structures and chemical reactivity, and (2) narrow acyltransferase (AT) specificity, which is limited to aliphatic CoA-linked extender units. In this report, we uncovered and characterized the first aromatic CoA-linked extender unit benzylmalonyl-CoA from the biosynthetic pathways of splenocin and enterocin in Streptomyces sp. CNQ431. Its synthesis employs a deamination/reductive carboxylation strategy to convert phenylalanine into benzylmalonyl-CoA, providing a link between amino acid and CoA-linked extender unit synthesis. By characterization of its selection, we further validated that AT domains of splenocin, and antimycin polyketide synthases are able to select this extender unit to introduce the phenyl group into their dilactone scaffolds. The biosynthetic machinery involved in the formation of this extender unit is highly versatile and can be potentially tailored for tyrosine, histidine and aspartic acid. The disclosed aromatic extender unit, amino acid-oriented synthetic pathway, and aromatic-selective AT domains provides a systematic breakthrough toward current knowledge of polyketide extender unit formation and selection, and also opens a route for further engineering of polyketide carbon scaffolds using amino acids.
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Grande Burgos, María José; López Aguayo, María Del Carmen; Pérez Pulido, Rubén; Galvez, Antonio; Lucas, Rosario
2017-09-01
Parsley can be implicated in foodborne illness, yet chopped parsley is used as an ingredient or garnish for multiple dishes. The aim of the present study was to determine the effect of two different treatments on the bacterial diversity of parsley: (i) coating with a pectin-EDTA solution containing the circular bacteriocin enterocin AS-48, and (ii) treatment by high hydrostatic pressure (HHP) at 600MPa for 8min. Control and treated parsley were stored in trays at 5°C for 10days. Both treatments reduced viable counts by 3.7 log cycles and retarded growth of survivors during storage. The bacterial diversity of the chopped parsley was studied by high throughput sequencing (Illumina Miseq). Bacterial diversity of control samples mainly consists of Proteobacteria (96.87%) belonging to genera Pseudomonas (69.12%), Rheinheimera (8.56%) and Pantoea (6.91%) among others. During storage, the relative abundance of Bacteroidetes (mainly Flavobacterium and Sphingobacterium) increased to 26.66%. Application of the pectin-bacteriocin-EDTA coating reduced the relative abundance of Proteobacteria (63.75%) and increased that of Firmicutes (34.70%). However, the relative abundances of certain groups such as Salmonella, Shigella and Acinetobacter increased at early storage times. Late storage was characterized by an increase in the relative abundance of Proteobacteria, mainly Pseudomonas. Upon application of HHP treatment, the relative abundance of Proteobacteria was reduced (85.88%) while Actinobacteria increased (8.01%). During early storage of HHP-treated samples, the relative abundance of Firmicutes increased. Potentially-pathogenic bacteria (Shigella) only increased in relative abundance by the end of storage. Results of the present study indicate that the two treatments had different effects on the bacterial diversity of parsley. The HHP treatment provided a safer product, since no potentially-pathogenic bacteria were detected until the end of the storage period. Copyright
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Radiosensitivity of lentil beam (Lens culinaris L.) to gamma-irradiation
Energy Technology Data Exchange (ETDEWEB)
Lee, Min Kyu; Ryu, Jaihyunk; Jeong, Sang Wook; Kim, Jin Baek; Kang, Si Young; Kwon, Soon Jae [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)
2017-02-15
We examined damages from gamma-irradiation and determined the optimal gamma ray dose for mutation breeding in lentil (Lens culinaris L.) bean. Four individual lines (L-C, L-2, L-8 and L-9), that have remarkable adaptability in South Korea were gamma-irradiated at doses of 50, 70, 100, 200, 300, 400, and 500 Gy. The germination rate of seed decreased as the dose increased over 50 Gy in all lines. However, LD{sub 50} and RD{sub 50} were different among lines. The median lethal doses (LD50) were approximately 127 (L-C), 74 (L-2), 95 (L-8), and 144 (L-9) Gy. The median reduction doses (RD{sub 50}) for plant height, number of leaves, root length, and flash weight were 156, 176, 150, and 180 Gy for L-C, 253, 198, 127, and 142 Gy for L-2, 188, 175, 200, and 190 Gy for L-8, and 162, 210, 224, and 184 for L-9, respectively. The growth characteristics of the M1 generation decreased as the dose increased over 70 Gy. The optimal doses of gamma irradiation for mutation breeding of lentil were determined to be 70 Gy (L-2, L-8) and 100 Gy (L-C, L-9). We performed the comet assay to observe nuclear DNA damage induced by gamma-irradiation. In comet assay, a clear difference was identified over 100 Gy treatments. With increasing doses of gamma-ray in the range of 50 to 500 Gy, the rate of head DNA was decreased significantly from 97.5% to 81.6%. Tail length was consecutively increased from 1.9 μm to 17.4 μm. Our result provides basic information for construction of mutant pools in lentils.
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Radiosensitivity of lentil beam (Lens culinaris L.) to gamma-irradiation
International Nuclear Information System (INIS)
Lee, Min Kyu; Ryu, Jaihyunk; Jeong, Sang Wook; Kim, Jin Baek; Kang, Si Young; Kwon, Soon Jae
2017-01-01
We examined damages from gamma-irradiation and determined the optimal gamma ray dose for mutation breeding in lentil (Lens culinaris L.) bean. Four individual lines (L-C, L-2, L-8 and L-9), that have remarkable adaptability in South Korea were gamma-irradiated at doses of 50, 70, 100, 200, 300, 400, and 500 Gy. The germination rate of seed decreased as the dose increased over 50 Gy in all lines. However, LD_5_0 and RD_5_0 were different among lines. The median lethal doses (LD50) were approximately 127 (L-C), 74 (L-2), 95 (L-8), and 144 (L-9) Gy. The median reduction doses (RD_5_0) for plant height, number of leaves, root length, and flash weight were 156, 176, 150, and 180 Gy for L-C, 253, 198, 127, and 142 Gy for L-2, 188, 175, 200, and 190 Gy for L-8, and 162, 210, 224, and 184 for L-9, respectively. The growth characteristics of the M1 generation decreased as the dose increased over 70 Gy. The optimal doses of gamma irradiation for mutation breeding of lentil were determined to be 70 Gy (L-2, L-8) and 100 Gy (L-C, L-9). We performed the comet assay to observe nuclear DNA damage induced by gamma-irradiation. In comet assay, a clear difference was identified over 100 Gy treatments. With increasing doses of gamma-ray in the range of 50 to 500 Gy, the rate of head DNA was decreased significantly from 97.5% to 81.6%. Tail length was consecutively increased from 1.9 μm to 17.4 μm. Our result provides basic information for construction of mutant pools in lentils
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OMPS/NPP PCA SO2 Total Column 1-Orbit L2 Swath 50x50km NRT
National Aeronautics and Space Administration — The OMPS-NPP L2 NM Sulfur Dioxide (SO2) Total and Tropospheric Column swath orbital collection 2 version 2.0 product contains the retrieved sulfur dioxide (SO2)...
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Leaderless Covert Networks : A Quantitative Approach
Husslage, B.G.M.; Lindelauf, R.; Hamers, H.J.M.
2012-01-01
Abstract: Lindelauf et al. (2009a) introduced a quantitative approach to investigate optimal structures of covert networks. This approach used an objective function which is based on the secrecy versus information trade-off these organizations face. Sageman (2008) hypothesized that covert networks
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Using Leadered Groups in Organizational Behavior and Management Survey Courses
Andre, Rae
2011-01-01
In organizational behavior and management survey courses, students are likely to maximize certain career-appropriate knowledge when their classroom groups are leadered rather than leaderless. Using leadered groups facilitates the learning of the professional and managerial skills associated with formal leadership while reducing some problematic…
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Rose, Natisha L.; Sporns, Peter; McMullen, Lynn M.
1999-01-01
The use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the detection of bacteriocins was investigated. A 30-s water wash of the sample on the MALDI-TOF MS probe was effective in removing contaminants of the analyte. This method was used for rapid detection of nisin, pediocin, brochocin A and B, and enterocin A and B from culture supernatants and for detection of enterocin B throughout its purification.
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Plasma l-citrulline concentrations in l-arginine-supplemented healthy dogs.
Flynn, K M; Kellihan, H B; Trepanier, L A
2017-08-01
To determine whether oral l-arginine increases plasma [l-citrulline] in dogs. Eleven healthy staff-owned dogs were used in this study. Dogs (n = 3) were given l-arginine (50mg/kg PO q8h) for 7 days, and plasma [l-arginine] and [l-citrulline] were analyzed by high performance liquid chromatography at baseline (BL), steady state trough, and 0.5, 1, 1.5, 2, 4, 6, and 8 h after final dosing on day 7. Eleven dogs were then treated with 100mg/kg l-arginine PO q8h for 7 days, and [l-arginine] and [l-citrulline] were measured at BL, steady state trough, and at peak 4 hrs after dosing (T4 hrs). - Plasma [l-arginine] and [l-citrulline] peaked at T4 hrs on the 50mg/kg dosage. Target outcome, modeled after human study results, of a doubling of [l-arginine] and a 25-30% increase in [l-citrulline] from BL were not reached. After the 100mg/kg dosage, plasma [l-arginine] increased from a BL median of 160.1 μM (range, 100.2-231.4 μM) to a peak of 417.4 μM (206.5-807.3 μM) at T4 hrs, and plasma [l-citrulline] increased from a BL median of 87.8 μM (59.1-117.1 μM) to peak of 102.2 μM (47.4-192.6 μM) at T4 hrs. Ten of eleven dogs showed a doubling of plasma [l-arginine] and 4/11 dogs achieved 25-30% or greater increases in plasma [l-citrulline]. No adverse effects on heart rate or blood pressure were noted. - Oral l-arginine dosage of 100mg/kg q8h doubles plasma [l-arginine] in healthy dogs, but conversion to l-citrulline is quite variable. Further evaluation of this dosage regimen in dogs with pulmonary hypertension is warranted. Copyright © 2017 Elsevier B.V. All rights reserved.
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Conveying the Complex: Updating U.S. Joint Systems Analysis Doctrine with Complexity Theory
2013-12-10
and useful to as broad 59See Peter Checkland and John Poulter, Learning for Action: A Short Definitive Account of Soft Systems Methodology and Its...Unstoppable Power of Leaderless Organizations. New York: Penguin Group, 2006. Checkland , Peter and Poulter, John. Learning for Action: A Short Definitive
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Novel Group of Leaderless Multipeptide Bacteriocins from Gram-Positive Bacteria.
Ovchinnikov, Kirill V; Chi, Hai; Mehmeti, Ibrahim; Holo, Helge; Nes, Ingolf F; Diep, Dzung B
2016-09-01
From raw milk we found 10 Lactococcus garvieae isolates that produce a new broad-spectrum bacteriocin. Though the isolates were obtained from different farms, they turned out to possess identical inhibitory spectra, fermentation profiles of sugars, and repetitive sequence-based PCR (rep-PCR) DNA patterns, indicating that they produce the same bacteriocin. One of the isolates (L. garvieae KS1546) was chosen for further assessment. Purification and peptide sequencing combined with genome sequencing revealed that the antimicrobial activity was due to a bacteriocin unit composed of three similar peptides of 32 to 34 amino acids. The three peptides are produced without leader sequences, and their genes are located next to each other in an operon-like structure, adjacent to the genes normally involved in bacteriocin transport (ABC transporter) and self-immunity. The bacteriocin, termed garvicin KS (GarKS), showed sequence homology to four multipeptide bacteriocins in databases: the known staphylococcal aureocin A70, consisting of four peptides, and three unannotated putative multipeptide bacteriocins produced by Bacillus cereus All these multipeptide bacteriocin loci show conserved genetic organization, including being located adjacent to conserved genetic determinants (Cro/cI and integrase) which are normally associated with mobile genetic elements or genome rearrangements. The antimicrobial activity of all multipeptide bacteriocins was confirmed with synthetic peptides, and all were shown to have broad antimicrobial spectra, with GarKS being the most active of them. The inhibitory spectrum of GarKS includes important pathogens belonging to the genera Staphylococcus, Bacillus, Listeria, and Enterococcus Bacterial resistance to antibiotics is a very serious global problem. There are no new antibiotics with novel antimicrobial mechanisms in clinical trials. Bacteriocins use antimicrobial mechanisms different from those of antibiotics and can kill antibiotic
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Indian Academy of Sciences (India)
L Ramello. Articles written in Pramana – Journal of Physics. Volume 60 Issue 4 April 2003 pp 817-828. Study of deconfinement in NA50 · Paula bordalo M C Abreu B Alessandro C Alexa R Arnaldi M Atayan C Baglin A Baldit M Bedjidian S Beolé V Boldea Paula Bordalo S R Borenstein C Borges A Bussiére L Capelli C ...
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International Nuclear Information System (INIS)
Bonzi, Edgardo V.; Badiger, Nagappa M.; Grad, Gabriela B.; Barrea, Raul A.; Figueroa, Rodolfo G.
2011-01-01
The L shell fluorescence cross-sections of the elements in range 45 ≤ Z ≤ 50 have been determined at 8 keV using Synchrotron radiation. The individual L X-ray photons, Ll, Lα, Lβ I , Lβ II , Lγ I and Lγ II produced in the target were measured with high resolution Si(Li) detector. The experimental set-up provided a low background by using linearly polarized monoenergetic photon beam, improving the signal-to-noise ratio. The experimental cross-sections obtained in this work were compared with available experimental data from Scofield Krause and Scofield and Puri et al. . These experimental values closely agree with the theoretical values calculated using Scofield and Krause data, except for the case of Lγ, where values measured of this work are slighter higher.
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Data processing for the multichannel pulse height analysis system ND-50/50, (1)
International Nuclear Information System (INIS)
Katagiri, Masaki
1977-03-01
The multichannel pulse height analysis system ND-50/50 manufactured by Nuclear Data Inc. consists of a 4096 channel pulse height analyzer and a small computer PDP-8/L (Digital Equipment Corporation). A conversational interpretive language, MACAL (Multichannel Analyzer CALculator) has been developed to analyze gamma-ray spectra in ND-50/50. It is a modification of the FOCAL (FOrmula CALculator) language of Digital Equipment Corporation. MACAL consists of imperative English commands and mathematical expressions, and has standard mathematical functions and functions for controlling the multichannel pulse height analyzer and I/O devices (high-speed reader, high-speed punch, and digital plotter). With MACAL, the following five programs were prepared : 1) program for controlling the multichannel pulse height analyzer and data handling, 2) program for automatically analyzing gamma-ray spectra obtained by germanium detectors, 3) program for automatically measuring characteristics of germanium detectors, 4) program for calculating the center energy of gamma-ray peaks, and 5) program for plotting the pulse height distribution and diagraming the results obtained with the programs. By combining the programs according to experimental purposes, the system can be highly effective. (auth.)
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Proceedings of the Summit on ANSAs: Understanding Strategic Roles and Operational Dynamics
2010-11-01
23 franchises ”, or what Marc Sagemann (2008) describes as “leaderless jihad”, calls into question whether this still remains a necessary...community at a function some months earlier. As he and one of the community members left the restaurant and arrived at their cars, there was a scratch
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Hobson, Charles J.; Strupeck, David; Griffin, Andrea; Szostek, Jana; Rominger, Anna S.
2014-01-01
A comprehensive educational program for teaching behavioral teamwork and team leadership skills was rigorously evaluated with 148 MBA students enrolled at an urban regional campus of a Midwestern public university. Major program components included (1) videotaped student teams in leaderless group discussion (LGD) exercises at the course beginning…
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Directory of Open Access Journals (Sweden)
Edgardo Bonzi
2014-02-01
Full Text Available Synchrotron radiation at 10 keV was used to experimentally determine the Ll, L, LI, LII, LI and LII fluorescence cross sections for elements with 45 < Z < 50, as part of an ongoing investigation at low energies. The measured data were compared with calculated values obtained using coefficients from Scofield, Krause and Puri et al. Received: 19 December 2013, Accepted: 20 January 2014; Reviewed by: J. P. Marques, Departamento de Física, Centro de Física Atómica, Fac. de Ciências, Universidade de Lisboa, Portugal.; Edited by: P. Weck; DOI: http://dx.doi.org/10.4279/PIP.060001 Cite as: E V Bonzi, G B Grad, R A Barrea, Papers in Physics 6, 060001 (2014
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Starus, Anna; Nocek, Boguslaw; Bennett, Brian; Larrabee, James A.; Shaw, Daniel L.; Sae-Lee, Wisath; Russo, Marie T.; Gillner, Danuta M.; Makowska-Grzyska, Magdalena; Joachimiak, Andrzej; Holz, Richard C.
2015-01-01
Binding of the competitive inhibitor L-captopril to the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase from Neisseria meningitidis (NmDapE) was examined by kinetic, spectroscopic, and crystallographic methods. L-Captopril, an angiotensin-converting enzyme (ACE) inhibitor, was previously shown to be a potent inhibitor of the DapE from Haemophilus influenzae (HiDapE) with an IC50 of 3.3 μM and a measured Ki of 1.8 μM and displayed a dose-responsive antibiotic activity toward Esch...
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Comparative study of induction of labour with Foley’s catheter inflated to 30 mL versus 60 mL
Indira I; Latha G; Lakshmi Narayanamma V
2016-01-01
Background: The ripeness of the cervix is an important determinant of the success of induction of labour. One of the mechanical methods of cervical ripening is the use of a transcervical Foley catheter. In this study we compared the efficacy in induction of labour of two insufflation volumes of Foley catheter bulb 30 mL and 60mL. Methods: This was a randomized, single-blind study conducted in 100 women, randomly allocated to the 30 mL group (n=50) and 60 mL group (n=50). Foley’s cath...
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Chen, Ziwei; Xu, Wei; Zhang, Wenli; Zhang, Tao; Jiang, Bo; Mu, Wanmeng
2018-04-01
l-Hexoses are rare sugars that are important components and precursors in the synthesis of biological compounds and pharmaceutical drugs. l-Rhamnose isomerase (L-RI, EC 5.3.1.14) is an aldose-ketose isomerase that plays a significant role in the production of l-sugars. In this study, a thermostable, l-sugar-producing L-RI from the hyperthermophile Caldicellulosiruptor obsidiansis OB47 was characterized. The recombinant L-RI displayed maximal activity at pH 8.0 and 85 °C and was significantly activated by Co 2+ . It exhibited a relatively high thermostability, with measured half-lives of 24.75, 11.55, 4.15 and 3.30 h in the presence of Co 2+ at 70, 75, 80 and 85 °C, respectively. Specific activities of 277.6, 57.9, 13.7 and 9.6 U mg -1 were measured when l-rhamnose, l-mannose, d-allose and l-fructose were used as substrates, respectively. l-Rhamnulose was produced with conversion ratios of 44.0% and 38.6% from 25 and 50 g L -1 l-rhamnose, respectively. l-Fructose was also efficiently produced by the L-RI, with conversion ratios of 67.0% and 58.4% from 25 and 50 g L -1 l-mannose, respectively. The recombinant L-RI could effectively catalyze the formation of l-rhamnulose and l-fructose, suggesting that it was a promising candidate for industrial production of l-rhamnulose and l-fructose. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.
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Directory of Open Access Journals (Sweden)
M. Bagheri Shirvan
2016-05-01
Full Text Available In order to evaluate intercropping of soybean (Glycine max L. cv. JK with sweet basil (Ocimum basilicum L. and borage (Borago officinalis L. with weed interference, an experiment was performed in randomized complete block design with 12 treatments and three replications at a field located 10 km of Shirvan during year of 2011. The treatments were included 75% soybean: 25%sweet basil, 50%soybean: 50% sweet basil, 25% soybean: 75% sweet basil, 75% soybean: 25% borage, 50% soybean: 50% borage and 25% soybean: 75% borage under weed infestation, in addition sole cropping of plants under weed control and weed interference. Intercropped plants had more success in reduction of weed density and biomass compared to monoculture. Soybean50: sweet basil50, reduced the weed density by 47.95% and 52.9%, and reduced the weed biomass by 68.91% and 61.87% more than sweet basil and soybean pure stand, respectively. Investigation of dry matter accumulation showed that increasing of plant proportion in intercropping caused increasing of plant dry matter. The height of soybean and borage was increased in intercropping and weed interference, while the highest height of sweet basil was observed in monoculture at second harvest. Biological and economical yield of soybean in intercropping with sweet basil was higher than intercropping with borage. The highest harvest index was related to 50:50 soybean: sweet basil ratio. In this ratio, the harvest index increased 4.9% compared to soybean monoculture. Yield of sweet basil and borage decreased with increasing of soybean rows in intercropping. Based on area-time equivalent ratio, soybean 75% with sweet basil and borage 25% (based on borage seed yield had 3% and 4% advantage compared to monoculture.
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Heath, Tahirah K; Lutz, Marlon R; Reidl, Cory T; Guzman, Estefany R; Herbert, Claire A; Nocek, Boguslaw P; Holz, Richard C; Olsen, Kenneth W; Ballicora, Miguel A; Becker, Daniel P
2018-01-01
A new enzymatic assay for the bacterial enzyme succinyl-diaminopimelate desuccinylase (DapE, E.C. 3.5.1.18) is described. This assay employs N6-methyl-N2-succinyl-L,L-diaminopimelic acid (N6-methyl-L,L-SDAP) as the substrate with ninhydrin used to detect cleavage of the amide bond of the modified substrate, wherein N6-methylation enables selective detection of the primary amine enzymatic product. Molecular modeling supported preparation of the mono-N6-methylated-L,L-SDAP as an alternate substrate for the assay, given binding in the active site of DapE predicted to be comparable to the endogenous substrate. The alternate substrate for the assay, N6-methyl-L,L-SDAP, was synthesized from the tert-butyl ester of Boc-L-glutamic acid employing a Horner-Wadsworth-Emmons olefination followed by an enantioselective reduction employing Rh(I)(COD)(S,S)-Et-DuPHOS as the chiral catalyst. Validation of the new ninhydrin assay was demonstrated with known inhibitors of DapE from Haemophilus influenza (HiDapE) including captopril (IC50 = 3.4 [± 0.2] μM, 3-mercaptobenzoic acid (IC50 = 21.8 [±2.2] μM, phenylboronic acid (IC50 = 316 [± 23.6] μM, and 2-thiopheneboronic acid (IC50 = 111 [± 16] μM. Based on these data, this assay is simple and robust, and should be amenable to high-throughput screening, which is an important step forward as it opens the door to medicinal chemistry efforts toward the discovery of DapE inhibitors that can function as a new class of antibiotics.
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Directory of Open Access Journals (Sweden)
Tahirah K Heath
Full Text Available A new enzymatic assay for the bacterial enzyme succinyl-diaminopimelate desuccinylase (DapE, E.C. 3.5.1.18 is described. This assay employs N6-methyl-N2-succinyl-L,L-diaminopimelic acid (N6-methyl-L,L-SDAP as the substrate with ninhydrin used to detect cleavage of the amide bond of the modified substrate, wherein N6-methylation enables selective detection of the primary amine enzymatic product. Molecular modeling supported preparation of the mono-N6-methylated-L,L-SDAP as an alternate substrate for the assay, given binding in the active site of DapE predicted to be comparable to the endogenous substrate. The alternate substrate for the assay, N6-methyl-L,L-SDAP, was synthesized from the tert-butyl ester of Boc-L-glutamic acid employing a Horner-Wadsworth-Emmons olefination followed by an enantioselective reduction employing Rh(I(COD(S,S-Et-DuPHOS as the chiral catalyst. Validation of the new ninhydrin assay was demonstrated with known inhibitors of DapE from Haemophilus influenza (HiDapE including captopril (IC50 = 3.4 [± 0.2] μM, 3-mercaptobenzoic acid (IC50 = 21.8 [±2.2] μM, phenylboronic acid (IC50 = 316 [± 23.6] μM, and 2-thiopheneboronic acid (IC50 = 111 [± 16] μM. Based on these data, this assay is simple and robust, and should be amenable to high-throughput screening, which is an important step forward as it opens the door to medicinal chemistry efforts toward the discovery of DapE inhibitors that can function as a new class of antibiotics.
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Directory of Open Access Journals (Sweden)
Yoonhyoung Lee
2018-03-01
Full Text Available One of the key issues in bilingual lexical representation is whether L1 processing is facilitated by L2 words. In this study, we conducted two experiments using the masked priming paradigm to examine how L2-L1 translation priming effects emerge when unbalanced, low proficiency, Korean-English bilinguals performed a lexical decision task. In Experiment 1, we used a 150 ms SOA (50 ms prime duration followed by a blank interval of 100 ms and found a significant L2-L1 translation priming effect. In contrast, in Experiment 2, we used a 60 ms SOA (50 ms prime duration followed by a blank interval of 10 ms and found a null effect of L2-L1 translation priming. This finding is the first demonstration of a significant L2-L1 translation priming effect with unbalanced Korean-English bilinguals. Implications of this work are discussed with regard to bilingual word recognition models.
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Directory of Open Access Journals (Sweden)
Heather J Beck
Full Text Available Analysis of the Escherichia coli transcriptome identified a unique subset of messenger RNAs (mRNAs that contain a conventional untranslated leader and Shine-Dalgarno (SD sequence upstream of the gene's start codon while also containing an AUG triplet at the mRNA's 5'- terminus (5'-uAUG. Fusion of the coding sequence specified by the 5'-terminal putative AUG start codon to a lacZ reporter gene, as well as primer extension inhibition assays, reveal that the majority of the 5'-terminal upstream open reading frames (5'-uORFs tested support some level of lacZ translation, indicating that these mRNAs can function both as leaderless and canonical SD-leadered mRNAs. Although some of the uORFs were expressed at low levels, others were expressed at levels close to that of the respective downstream genes and as high as the naturally leaderless cI mRNA of bacteriophage λ. These 5'-terminal uORFs potentially encode peptides of varying lengths, but their functions, if any, are unknown. In an effort to determine whether expression from the 5'-terminal uORFs impact expression of the immediately downstream cistron, we examined expression from the downstream coding sequence after mutations were introduced that inhibit efficient 5'-uORF translation. These mutations were found to affect expression from the downstream cistrons to varying degrees, suggesting that some 5'-uORFs may play roles in downstream regulation. Since the 5'-uAUGs found on these conventionally leadered mRNAs can function to bind ribosomes and initiate translation, this indicates that canonical mRNAs containing 5'-uAUGs should be examined for their potential to function also as leaderless mRNAs.
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L-Lake zooplankton: L-Lake/Steel Creek Biological Monitoring Program, November 1985--December 1991
Energy Technology Data Exchange (ETDEWEB)
Bowers, J.A. [Westinghouse Savannah River Co., Aiken, SC (United States); Bowen, M. [Normandeau Associates, Inc., New Ellenton, SC (United States)
1992-03-01
The L- Lake Biological Monitoring Program was designed to meet environmental regulatory requirements associated with the restart of L-Reactor and address portions of Section 316(a) of the Clean Water Act, which requires an applicant for a discharge permit to provide scientific evidence that the discharge causes no significant impact on the indigenous ecosystem. The Department of Energy (DOE) must demonstrate that the discharge of L-Reactor affluent into L Lake will not inhibit the eventual establishment of a ``Balanced Biological Community`` (BBC) in at least 50% of the lake. This report details results of monitoring zooplankton populations in L-Lake.
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L-Lake zooplankton: L-Lake/Steel Creek Biological Monitoring Program, November 1985--December 1991
International Nuclear Information System (INIS)
Bowers, J.A.; Bowen, M.
1992-03-01
The L- Lake Biological Monitoring Program was designed to meet environmental regulatory requirements associated with the restart of L-Reactor and address portions of Section 316(a) of the Clean Water Act, which requires an applicant for a discharge permit to provide scientific evidence that the discharge causes no significant impact on the indigenous ecosystem. The Department of Energy (DOE) must demonstrate that the discharge of L-Reactor affluent into L Lake will not inhibit the eventual establishment of a ''Balanced Biological Community'' (BBC) in at least 50% of the lake. This report details results of monitoring zooplankton populations in L-Lake
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C-11 production with MC-50 cyclotron and synthesis of L-[11C-methyl] methionine
International Nuclear Information System (INIS)
Kim, Sang Wook; Hur, Min Goo; Yang, Seung Dae; Ahn, Soon Hyuk; Chun, Kweon Soo
2003-01-01
L-[ 11 C-methyl] methionine was prepared via no-carrier-added(nca) fast S-alkylation of L-homocysteine with [ 11 C]CH 3 I using solid support (Al 2 O 3 /KF)at room temperature in ethanol. The radiochemical yield of methylation was 90.2%. After reaction, no radiochemical impurity was detected but traces of L-homocysteine precursor were monitored by UV detector. The purification was archived by passing successively through a C 18 and alumina sep-pak. the radiochemical purity of L-[ 11 C-methyl] methionine was over 98% after purification and total elapsed time to prepare was 10min from [ 11 C]CH 3 I delivery
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International Nuclear Information System (INIS)
Tanimura, Makoto; Koyama, Yasumasa
2006-01-01
The influence of antiphase boundaries (APBs) on the kinetic process of the L1 2 → D0 22 structural change in an Ni 3 Al 0.45 V 0.50 alloy has been investigated by transmission electron microscopy. The structural change includes two kinetic factors, i.e., the periodic introduction of antiphase-shifted planes (APSPs) in the L1 2 structure and V diffusion in the L1 2 matrix. Our results revealed that APB migration was accompanied by V diffusion as if to sweep the V atoms out of the antiphase domains (APDs). It was also found that the APBs served as the nucleation sites of the D0 22 regions, because the combination of the migrated APBs produced the APSPs in the L1 2 structure. On this basis, it is proposed that the APBs bring together the two kinetic factors in the process of the L1 2 → D0 22 structural change, the physical origin of which is the variation in the charge density distribution of the APDs due to APB migration
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Bioactive phenylpropanoid analogues from Piper betle L. var. birkoli leaves.
Atiya, Akhtar; Sinha, Barij Nayan; Lal, Uma Ranjan
2017-11-01
Phytochemical analyses of the chloroform extract of Piper betle L. var. birkoli, Piperaceae, leaves led to the isolation of two new phenylpropanoid analogues: bis-chavicol dodecanoyl ester (2) and bis-hydroxychavicol dodecanoyl ester (3), along with one known compound: allyl-3-methoxy-4-hydroxybenzene (1) on the basis of spectroscopic data 1D ( 1 H and 13 C) and 2D ( 1 H- 1 H COSY and HMBC) NMR, as well as ESI-MS, FT-IR, HR-ESI-MS and LC-ESI-MS. Compound 2 and 3 exhibited excellent antioxidant DPPH radical scavenging activity with IC 50 values of 12.67 μg/mL and 1.08 μg/mL compared to ascorbic acid as a standard antioxidant drug with IC 50 value of 6.60 μg/mL. Evaluation of cytotoxic activity against two human oral cancer cell lines (AW13516 and AW8507) showed significant effect with GI 50 values of 19.61 and 23.01 μg/mL for compound 2 and 10.25 and 13.12 μg/mL for compound 3, compared to Doxorubicin ® as a standard cytotoxic drug with GI 50 value of < 10 μg/mL.
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L-Lake fish: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1991
International Nuclear Information System (INIS)
Sayers, R.E. Jr.; Mealing, H.G. III
1992-04-01
The L Lake Biological Monitoring Program was designed to meet environmental regulatory requirements associated with the re-start of L-Reactor and address portions of Section 316(a) of the Clean Water Act, which requires an applicant for a discharge permit to provide scientific evidence that the discharge causes no significant impact on the indigenous ecosystem. The Department of Energy (DOE) must demonstrate that the discharge of L-Reactor effluent into L Lake will not inhibit the eventual establishment of a ''Balanced Biological Community'' (BBC) in at least 50% of the lake
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L-Lake fish: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1991
Energy Technology Data Exchange (ETDEWEB)
Sayers, R.E. Jr.; Mealing, H.G. III [Normandeau Associates, Inc., New Ellenton, SC (United States)
1992-04-01
The L Lake Biological Monitoring Program was designed to meet environmental regulatory requirements associated with the re-start of L-Reactor and address portions of Section 316(a) of the Clean Water Act, which requires an applicant for a discharge permit to provide scientific evidence that the discharge causes no significant impact on the indigenous ecosystem. The Department of Energy (DOE) must demonstrate that the discharge of L-Reactor effluent into L Lake will not inhibit the eventual establishment of a ``Balanced Biological Community`` (BBC) in at least 50% of the lake.
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Micucci, Matteo; Angeletti, Andrea; Cont, Massimiliano; Corazza, Ivan; Aldini, Rita; Donadio, Elisa; Chiarini, Alberto; Budriesi, Roberta
2016-05-01
Olea europaea L. leaves extract (Oe) and Hybiscus sabdariffa L. flowers extract (Hs) have calcium antagonistic properties. Aim of this work was to study the cardiovascular effects of Pres Phytum(®), a nutraceutical formulation containing a mixture of the two extracts and the excipients, and investigate its possible off-target effects, using in vitro biological assays on guinea pig isolated organs. Cardiovascular effects were assessed using guinea pig atria and aorta. The effects of Pres Phytum on spontaneous gastrointestinal, urinary, and respiratory tracts smooth muscle contractility were evaluated. Pres Phytum exerted a vasorelaxant effect (IC50 = 2.38 mg/mL) and a negative chronotropic effect (IC50 = 1.04 mg/mL) at concentrations lower than those producing smooth muscle spontaneous contractility alterations in the other organs. Compared to Pres Phytum, the mixture did not exert negative inotropic activity, while it maintained a negative chronotropic efficacy (IC50 = 1.04 mg/mL). These experimental data suggest a possible nutraceutical use of this food supplement for the management of preclinical hypertension.
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Energy Technology Data Exchange (ETDEWEB)
Jeanmaire, L; Jammet, H [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires
1959-07-01
A procedure for the quantitative analysis of uranium in urine is described. The residue obtained by mineralization is dissolved in diluted hydrochloric acid. Uranium is separated by fixation on a permutit 50 column, elution with 0,2 M oxalic acid and electrodeposition on nickel. Uranium is then measured by {alpha} counting. It is thus possible to detect less than 1 pico-curie of uranium in the sample. (author) [French] Cet article decrit une technique de dosage de l'uranium dans l'urine. Apres mineralisation, le residu est dissous dans l'acide chlorhydrique dilue. L'uranium est separe par fixation, sur une colonne de permutite 50, elution au moyen d'acide oxalique 0,2 M et depot electrolytique sur nickel. La mesure faite par comptage {alpha} permet de detecter moins de 1 picocurie d'uranium dans l'echantillon. (auteur)
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File list: DNS.Utr.50.AllAg.Endometrial_stromal_cells [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available DNS.Utr.50.AllAg.Endometrial_stromal_cells hg19 DNase-seq Uterus Endometrial stroma...l cells http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/DNS.Utr.50.AllAg.Endometrial_stromal_cells.bed ...
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Shui, Junfeng; An, Yu; Ma, Yongqing; Ichizen, Nobumasa
2010-10-01
This study investigated allelopathy and its chemical basis in nine switchgrass ( Panicum virgatum L.) accessions. Perennial ryegrass ( Lolium perenne L.) and alfalfa ( Medicago sativa L.) were used as test species. Undiluted aqueous extracts (5 g plant tissue in 50 ml water) from the shoots and roots of most of the switchgrass accessions inhibited the germination and growth of the test species. However, the allelopathic effect of switchgrass declined when extracts were diluted 5- or 50-fold. Seedling growth was more sensitive than seed germination as an indicator of allelopathic effect. Allelopathic effect was related to switchgrass ecotype but not related to ploidy level. Upland accessions displayed stronger allelopathic potential than lowland accessions. The aqueous extract from one switchgrass accession was separated into phenols, organic acids, neutral chemicals, and alkaloids, and then these fractions were bioassayed to test for allelopathic potential. Alkaloids had the strongest allelopathic effect among the four chemical fractions. In summary, the results indicated that switchgrass has allelopathic potential; however, there is not enough evidence to conclude that allelopathic advantage is the main factor that has contributed to the successful establishment of switchgrass on China’s Loess Plateau.
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Directory of Open Access Journals (Sweden)
Irena Rogelj
2011-03-01
Full Text Available The presence of gene determinants for different bacteriocins has been already demonstrated in traditional Slovenian types of raw milk cheeses ‘Tolminc’ and ‘Kraški’. These genes were present also in the cultivable microbiota. In this research the aim was to establish how the presence of gene determinants for bacteriocins in microbial consortia is reflected in its antimicrobial activity. In addition, one of the goals was to determine whether the strains that carry gene determinants for bacteriocins have any competitive growth advantage in microbial population. Microbial consortium of ‘Tolminc’ cheese was propagated in milk and examined at the end of propagation its antimicrobial activity and the presence of gene determinants for bacteriocins. Comparison of the results obtained before and after propagation leaded to the conclusion that most of the strains possessing gene determinants for bacteriocins were unable to persist during propagation. The strains which did persist during propagation carried gene determinants for enterocins P, L50B and cytolysin. Antimicrobial activity of consortium before and after propagation was not substantially different and cannot be attributed to any of detected bacteriocins.
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Energy Technology Data Exchange (ETDEWEB)
Burnside, W [Mountain View, CA (United States)
2015-06-15
Purpose: Xoft provides a set of 316L Stainless Steel Rigid Shields to be used with their 50 kV X-ray source for Breast IORT treatments. Modeling the different shield sizes in MCNP provides information to help make clinical decisions for selecting the appropriate shield size. Methods: The Xoft Axxent 50 kV Electronic Brachytherapy System has several applications in radiation therapy, one of which is treating cancer of the breast intraoperatively by placing the miniaturized X-ray tube inside an applicator balloon that is expanded to fill the lumpectomy bed immediately following tumor removal. The ribs, lung, and muscular chest wall are all regions at risk to receive undesired dose during the treatment. A Xoft 316L Stainless Steel Rigid Shield can be placed between the intracostal muscles of the chest wall and the remaining breast tissue near the balloon to attenuate the beam and protect these organs. These shields are provided in 5 different sizes, and the effects on dose to the surrounding tissues vary with shield size. MCNP was used to model this environment and tally dose rate to certain regions of interest. Results: The average rib dose rate calculated using 0cm (i.e., no shield), 3cm, and 5cm diameter shields were 26.89, 15.43, and 8.91 Gy/hr respectively. The maximum dose rates within the rib reached 94.74 Gy/hr, 53.56 Gy/hr, and 31.44 Gy/hr for the 0cm, 3cm, and 5cm cases respectively. The shadowing effect caused by the steel shields was seen in the 3-D meshes and line profiles. Conclusion: This model predicts a higher dose rate to the underlying rib region with the 3cm shield compared to the 5cm shield; it may be useful to select the largest possible diameter when choosing a shield size for a particular IORT patient. The ability to attenuate the beam to reduce rib dose was also confirmed. Research sponsored by Xoft Inc, a subsidiary of iCAD.
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File list: Pol.ALL.50.RNA_Polymerase_III.AllCell [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available Pol.ALL.50.RNA_Polymerase_III.AllCell mm9 RNA polymerase RNA Polymerase III All cel...l types ERX204069 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.ALL.50.RNA_Polymerase_III.AllCell.bed ...
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Hatakeyama, T; Kimura, M
1988-03-15
Ribosomal proteins were extracted from 50S ribosomal subunits of the archaebacterium Halobacterium marismortui by decreasing the concentration of Mg2+ and K+, and the proteins were separated and purified by ion-exchange column chromatography on DEAE-cellulose. Ten proteins were purified to homogeneity and three of these proteins were subjected to sequence analysis. The complete amino acid sequences of the ribosomal proteins L25, L29 and L31 were established by analyses of the peptides obtained by enzymatic digestion with trypsin, Staphylococcus aureus protease, chymotrypsin and lysylendopeptidase. Proteins L25, L29 and L31 consist of 84, 115 and 95 amino acid residues with the molecular masses of 9472 Da, 12293 Da and 10418 Da respectively. A comparison of their sequences with those of other large-ribosomal-subunit proteins from other organisms revealed that protein L25 from H. marismortui is homologous to protein L23 from Escherichia coli (34.6%), Bacillus stearothermophilus (41.8%), and tobacco chloroplasts (16.3%) as well as to protein L25 from yeast (38.0%). Proteins L29 and L31 do not appear to be homologous to any other ribosomal proteins whose structures are so far known.
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John T. Dunlop e os 50 anos do Industrial Relations Systems
Directory of Open Access Journals (Sweden)
Carlos Henrique Horn
2009-01-01
Full Text Available Dans cet article, on présente l'oeuvre Industrial Relations Systems, de John Thomas Dunlop, publiée en 1958, qui a exercé une grande influence dans l'étude des relations du travail dans l'industrie selon la tradition anglo-américaine des Industrial relations au long des 50 dernières années. Outre une note biographique sur l'auteur et la présentation du cadre universitaire à l'origine de l'ouvrage, dans cet article on réexamine le concept-clé de système des relations du travail dans l'industrie tout en présentant les éléments qui composent ce système en accord avec le caractère analytique de Dunlop. Deux brèves sections complètent l'article: l'une sur les raisons de l'absence de Dunlop au Brésil, et l'autre tirant quelques leçons du livre.
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Dal Picolo, Camilla R; Bezerra, Mariana P; Gomes, Kaio S; Passero, Luiz Felipe D; Laurenti, Marcia D; Martins, Euder Glendes A; Sartorelli, Patricia; Lago, João Henrique G
2014-09-01
Bioactivity-guided fractionation of EtOH extract from the leaves of Piper aduncum L. (Piperaceae) afforded a new dihydrochalcone, named adunchalcone. Its structure was elucidated on the basis of their spectroscopic data, primarily NMR and MS. Adunchalcone was evaluated against promastigote forms of Leishmania (L.) amazonensis, L. (V.) braziliensis, L. (V.) shawi, and L. (L.) chagasi and displayed 50% effective concentrations (EC50) of 11.03, 26.70, and 11.26 μM, as well as selective indexes of 4.86, 2.01, 4.76 and 0.50, respectively. This compound was also tested against intracellular forms of L. (L.) amazonensis, displaying weak activity, in comparison to reference drug amphotericin B. However, despite reduced effect of adunchalcone against amastigotes of L. (L.) amazonensis, this work opens the perspective to use this particular molecule as a scaffold for the design of novel and selective drug candidates for neglected diseases, mainly leishmaniasis. Copyright © 2014 Elsevier B.V. All rights reserved.
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2010-10-01
... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false New Mexico. 32.50 Section 32.50 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE... § 32.50 New Mexico. The following refuge units have been opened for hunting and/or fishing, and are...
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De Angelis, Gessica
2015-01-01
The present study examines two factors in relation to English L3 proficiency development and school performance in a third language: (a) parental education and (b) second language exposure within the living community. Participants (n?=?50) are Italian L1 students with German L2 and English L3. All students (eighth grade, 14 years of age) were…
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Minor oxygenated cannabinoids from high potency Cannabis sativa L.
Ahmed, Safwat A; Ross, Samir A; Slade, Desmond; Radwan, Mohamed M; Khan, Ikhlas A; ElSohly, Mahmoud A
2015-09-01
Nine oxygenated cannabinoids were isolated from a high potency Cannabis sativa L. variety. Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D NMR, HRMS and GC-MS. These minor compounds include four hexahydrocannabinols, four tetrahydrocannabinols, and one hydroxylated cannabinol, namely 9α-hydroxyhexahydrocannabinol, 7-oxo-9α-hydroxyhexa-hydrocannabinol, 10α-hydroxyhexahydrocannabinol, 10aR-hydroxyhexahydrocannabinol, Δ(9)-THC aldehyde A, 8-oxo-Δ(9)-THC, 10aα-hydroxy-10-oxo-Δ(8)-THC, 9α-hydroxy-10-oxo-Δ(6a,10a)-THC, and 1'S-hydroxycannabinol, respectively. The latter compound showed moderate anti-MRSa (IC50 10.0 μg/mL), moderate antileishmanial (IC50 14.0 μg/mL) and mild antimalarial activity against Plasmodium falciparum (D6 clone) and P. falciparum (W2 clone) with IC50 values of 3.4 and 2.3 μg/mL, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Ortega Blázquez, Irene; Grande Burgos, María J; Pérez-Pulido, Rubén; Gálvez, Antonio; Lucas, Rosario
2018-01-01
The aim of this study was to determine the impact of activated plastic films with thymol and enterocin AS-48 and high-hydrostatic pressure (HP) treatment on the bacterial load and bacterial diversity of vacuum-packaged sea bream fillets under refrigerated storage for 10 days. The activated film and the HP treatment reduced aerobic mesophiles viable counts by 1.46 and 2.36 log cycles, respectively, while the combined treatment achieved a reduction of 4.13 log cycles. HP and combined treatments resulted in longer delays in bacterial growth. Proteobacteria were the dominant phyla in sea bream fillets. The relative abundance of Firmicutes increased by the end of storage both in controls and in samples treated by HP singly or in combination with the activated films. The predominant operational taxonomic units (OTUs) found at time 0 in control samples ( Listeria, Acinetobacter, Pseudomonas, Enterobacteriaceae, Chryseobacterium ) rapidly changed during storage (with an increase of Vibrio, Photobacterium , and Shewanella together with Cloacibacterium and Lactobacillales by the end of storage). The activated film and the HP treatment induced drastic changes in bacterial diversity right after treatments (with Comamonadaceae, Methylobacterium, Acidovorax , and Sphingomonas as main OTUs) and also induced further modifications during storage. Bacterial diversity in activated film samples was quite homogeneous during storage (with Vibrio, Photobacterium , and Shewanella as main OTUs) and approached control samples. HP treatments (singly or in combination with activated films) determined a high relative abundance of Acinetobacter (followed by Pseudomonas and Shewanella ) during early storage as well as a higher relative abundance of lactic acid bacteria by the end of storage. The results indicate that the complex dynamics of bacterial populations in the refrigerated sea bream fillets are markedly influenced by treatment and antimicrobials applied.
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Directory of Open Access Journals (Sweden)
Irene Ortega Blázquez
2018-02-01
Full Text Available The aim of this study was to determine the impact of activated plastic films with thymol and enterocin AS-48 and high-hydrostatic pressure (HP treatment on the bacterial load and bacterial diversity of vacuum-packaged sea bream fillets under refrigerated storage for 10 days. The activated film and the HP treatment reduced aerobic mesophiles viable counts by 1.46 and 2.36 log cycles, respectively, while the combined treatment achieved a reduction of 4.13 log cycles. HP and combined treatments resulted in longer delays in bacterial growth. Proteobacteria were the dominant phyla in sea bream fillets. The relative abundance of Firmicutes increased by the end of storage both in controls and in samples treated by HP singly or in combination with the activated films. The predominant operational taxonomic units (OTUs found at time 0 in control samples (Listeria, Acinetobacter, Pseudomonas, Enterobacteriaceae, Chryseobacterium rapidly changed during storage (with an increase of Vibrio, Photobacterium, and Shewanella together with Cloacibacterium and Lactobacillales by the end of storage. The activated film and the HP treatment induced drastic changes in bacterial diversity right after treatments (with Comamonadaceae, Methylobacterium, Acidovorax, and Sphingomonas as main OTUs and also induced further modifications during storage. Bacterial diversity in activated film samples was quite homogeneous during storage (with Vibrio, Photobacterium, and Shewanella as main OTUs and approached control samples. HP treatments (singly or in combination with activated films determined a high relative abundance of Acinetobacter (followed by Pseudomonas and Shewanella during early storage as well as a higher relative abundance of lactic acid bacteria by the end of storage. The results indicate that the complex dynamics of bacterial populations in the refrigerated sea bream fillets are markedly influenced by treatment and antimicrobials applied.
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Ortega Blázquez, Irene; Grande Burgos, María J.; Pérez-Pulido, Rubén; Gálvez, Antonio; Lucas, Rosario
2018-01-01
The aim of this study was to determine the impact of activated plastic films with thymol and enterocin AS-48 and high-hydrostatic pressure (HP) treatment on the bacterial load and bacterial diversity of vacuum-packaged sea bream fillets under refrigerated storage for 10 days. The activated film and the HP treatment reduced aerobic mesophiles viable counts by 1.46 and 2.36 log cycles, respectively, while the combined treatment achieved a reduction of 4.13 log cycles. HP and combined treatments resulted in longer delays in bacterial growth. Proteobacteria were the dominant phyla in sea bream fillets. The relative abundance of Firmicutes increased by the end of storage both in controls and in samples treated by HP singly or in combination with the activated films. The predominant operational taxonomic units (OTUs) found at time 0 in control samples (Listeria, Acinetobacter, Pseudomonas, Enterobacteriaceae, Chryseobacterium) rapidly changed during storage (with an increase of Vibrio, Photobacterium, and Shewanella together with Cloacibacterium and Lactobacillales by the end of storage). The activated film and the HP treatment induced drastic changes in bacterial diversity right after treatments (with Comamonadaceae, Methylobacterium, Acidovorax, and Sphingomonas as main OTUs) and also induced further modifications during storage. Bacterial diversity in activated film samples was quite homogeneous during storage (with Vibrio, Photobacterium, and Shewanella as main OTUs) and approached control samples. HP treatments (singly or in combination with activated films) determined a high relative abundance of Acinetobacter (followed by Pseudomonas and Shewanella) during early storage as well as a higher relative abundance of lactic acid bacteria by the end of storage. The results indicate that the complex dynamics of bacterial populations in the refrigerated sea bream fillets are markedly influenced by treatment and antimicrobials applied. PMID:29541064
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Directory of Open Access Journals (Sweden)
Latif Abdul
2004-11-01
Full Text Available Abstract Background The flower bud of Syzygium aromaticum (L. Merr. & Perry. (clove has been used in Unani medicine since ancient times for the treatment of male sexual disorders. The present study is aimed to investigate the effect of 50% ethanolic extract of clove on general mating behaviour, libido, potency along with its likely gastric ulceration and adverse effects on sexually normal male albino rats. Methods The suspension of the extract was administered orally at the dose of 100, 250, and 500 mg / kg, to different groups of male rats (n = 6 once a day for seven days. The female albino rats involved in mating were made receptive by hormonal treatment. The general mating behaviour, libido and potency were determined and compared with the standard reference drug sildenafil citrate. The probable gastric ulceration and adverse effects of the extract were also evaluated. Results Oral administration of the extract significantly increased the Mounting Frequency, Intromission Frequency; Intromission Latency, Erections; Quick Flips, Long Flips as well as aggregate of penile reflexes and caused significant reduction in the Mounting Latency and Post Ejaculatory Interval. The most appreciable effect of the extract was observed at the dose of 500 mg/kg. The test drug was also found to be devoid of any conspicuous gastric ulceration and adverse effects. Conclusion The results indicated that the 50% ethanolic extract of clove produced a significant and sustained increase in the sexual activity of normal male rats, without any conspicuous gastric ulceration and adverse effects. Thus, the resultant aphrodisiac effectivity of the extract lends support to the claims for its traditional usage in sexual disorders.
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Directory of Open Access Journals (Sweden)
Abiodun A. Denloye
2010-01-01
Full Text Available Laboratory bioassays were conducted to investigate the bioactivity of powders, extracts, and essential oils from Allium sativum L. (Alliaceae and A. fistulosum L. (Liliaceae against adults, eggs, and larvae of Callosobruchus maculatus F. (Coleoptera: Bruchidae. On the basis of 48 hr median lethal toxicity (LC50, test plant powders and extracts from A. sativum were more toxic to C. maculatus adults than those from A. fistulosum. The 48 hr LC50 values for the powder against the test insect species were 9.66 g/kg and 26.29 g/kg for A. sativum and A. fistulosum, respectively. Also the 48 hr LC50 values obtained show that aqueous extracts of the test plant species, 0.11 g/L (A. sativum and 0.411 g/L (A. fistulosum were more toxic to C. maculatus than the corresponding ethanol extracts. There was no significant difference in the toxicity of vapours from the two test plant species against C. maculatus, although A. sativum gave lower values. The study shows that A. sativum and A. fistulosum have potentials for protecting stored cowpea from damage by C. maculatus.
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Energy Technology Data Exchange (ETDEWEB)
Bastug, Arif [Department of Physics Education, College of Education, Erzincan University, 24030 Erzincan (Turkey)], E-mail: abastug40@hotmail.com
2008-03-15
The cross-sections for the production of L{sub {iota}}, L{sub {alpha}}, L{sub {beta}} and L{sub {gamma}} X-ray fluorescence (XRF) in Er, Ta, W, Au, Hg, Tl, Pb and Bi by photons with energies in the range 38-59.5 keV have been measured, using a standard doublereflection experimental set-up. Measurements have been performed using an annular 241 Am primary source and X-ray emitting secondary-exciter system. Experimental cross-sections have been compared with the theoretically calculated values of L X-ray cross-sections and fairly good agreement is observed between the experimental and theoretical values.
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Mõttevabaduse edendajad jagavad omavahel 50 000 eurot / Priit Pullerits
Pullerits, Priit, 1965-
2005-01-01
50 000 euro suurune Sahharovi mõttevabaduse auhind läheb tänavu jagamisele kolme võitja vahel: preemia jagavad omavahel julmade islamiseaduste vastu sõdiv Nigeeria naisjurist Hauwa Ibrahim, meediavabaduse eest võitlev rahvusvaheline ühendus Piirideta Ajakirjanikud ja Kuuba dissidentide naissoost sugulased. Lisa: Laureaadid
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Anti-Fungal activity of essential oil from Baeckea frutescens L against Pleuratus ostreatus
Jemi, Renhart; Barus, Ade Irma; Nuwa, Sarinah, Luhan, Gimson
2017-11-01
Ujung Atap is an herb that have distinctive odor on its leaves. The plant's essential oil contains bioactive compounds but has not been investigated its anti-fungal activity against Pleurotus ostreatus. Essential oil from Ujung Atap leaves is one environmentally friendly natural preservative. This study consisted of distillation Ujung Atap leaves with boiled method, determining the number of acid, essential oil ester, and anti-fungal activity against Pleurotus ostreatus. Analysis of the data to calculate anti-fungal activity used probit analysis method to determine the IC50. Results for the distillation of leaves Ujung Atap produce essential oil yield of 0.071% and the average yield of the acid number and the ester of essential oils Ujung Atap leaves are 5.24 and 12.15. Anti-fungal activity Pleurotus ostreatus at a concentration of 1000 µg/mL, 100 µg/mL, 75 µg/mL, 50 µg/mL and 100 µg/mL BA defunct or fungi was declared dead, while at a concentration of 25 µg/mL, 10 µg/mL and 5 µg/mL still occur inhibitory processes. Results obtained probit analysis method IC50 of 35.48 mg/mL; means the essential oil of Ujung Atap leaf can inhibit fungal growth by 50 percent to 35.48 µg/mL concentration.
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Energy Technology Data Exchange (ETDEWEB)
Bovi, Jose Eduardo
2000-07-01
The research had the aim of evaluating the effects of low doses of Cobalt-60 gamma radiation on seeds of radish (Raphanus sativus L.) cultiva Champion, cultivars Nantes Forto (european origin) and Brasilia (Rio Grande do Sul origin) carrot (Daucus carota L. var. sativus (Hoffm.) Thell), and red beet (Beta vulgaris L.) cultivar Tall Top Early Wonder before sowing, its effects on plant growth, on the yield and roots storage of two tillages: with sowing in the same day of radiation and six days after radiation seeds. The data showed that the seeds radiation did not interfered negatively on plants growth, and the species presented differences as roots production and doses on both plantation: radish with 5,0 Gy and 2,5 Gy doses respectively to the first and the second sowings, Brasilia carrot with 2,5 Gy dose to both sowings. Nantes carrot with 2,5 Gy and 5,0 Gy respectively to the first and the second sowings, and beet with 7,5 Gy and 5,0 Gy respectively to the first and the second plantations. There is not statistics difference by Tukey test (5% and 1%) and none relation between seeds radiation and loss weight on roots storage. (author)
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2009-04-01
to Guerrilla Warfare and Underground Operations, ed. R. K. Brown, (Boulder, CO: Panther Publications, Inc., 1965); and Trinquier. Espionage related...Leaderless Resistance…has been used by white supremacists, anti-abortion and environmental activists, and animal rights groups. I argue that, despite...Stenson, Chad Oman, and Branko Lustig, “Scene 5,” Black Hawk Down, DVD, directed by Ridley Scott, (Culver City, CA: Columbia Pictures, 2002). 225 Ney
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Preparation of sup(99m) Tc - L - asparagine
International Nuclear Information System (INIS)
Okada, H.; Silva, C.P.G. da; Pereira, N.P.S. de.
1986-05-01
The interrelationship between technetium-99m, different reducing agents and the L-asparagine is studied. The maximum labelling yield, aboult 95%, is obtained by using the following molar ratios for ligand to reducing agents: L-asparagine: stannous ascorbate, 150:1; the L-asparagine: ascorbic acid, 50:1, and L-asparagine:stannous chloride, 800:1. This radiopharmaceutical is used for visualization of dependent asparagine tumours. (Author) [pt
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Effects of gamma irradiation on fresh and dry weights of plant parts in Physalis L
International Nuclear Information System (INIS)
Raghava, R.P.; Raghava, Nisha
1989-01-01
20 KR irradiations on Physalis peruviana L. and P. angulta L. seem to be the best dose for plant growth. 40 and 50 KR doses were inhibitory to both, and 50 KR was found to be almost lethal (LD 50 ). (author). 14 refs
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International Nuclear Information System (INIS)
Jangi, M.S.; Ibrahim, Hasan
1983-01-01
A total of 24 isolates of Bacillus thuringiensis (Berliner), resistant to a γ-radiation dose of 100 krad, were screened for their toxicity to larval silkworms, Bombyxmori(L.), and 15 of them were subsequently tested for their toxicity to larval diamond-back moth, Plutella xylostella(L.). The LC 50 's of these isolates to B. mori ranged from 1.6 X 10 5 to 6.0 X 10 3 spores/mL or from 5.9 to 0.3 μg cellular protein/mL. The irradiation treatment produced isolates which were significantly more toxic to P. xylostella (LC 50 4 spores/mL or 3.7 μg cellular protein/mL) and/ or less toxic to B. mori (LC 50 > 2.3 X 10 4 spores/mL or 1.0 μg cellular protein/mL) than the parent commercial strain
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Directory of Open Access Journals (Sweden)
Andrey P. Lopes
2013-01-01
Full Text Available The crude ethanolic extract from aerial parts of Pothomorphe umbellata L. (Piperaceae and fractions obtained by partitions sequentially among water-methanol, methylene chloride, and ethyl acetate, as well as the major constituent, 4-nerolidylcatechol, were, respectively, evaluated and evidenced for antioxidant and cytotoxic effects through fluorometric microplate and microculture tetrazolium assays in HL-60 cells. The crude ethanolic extract demonstrated the preeminent antioxidant activity (IC50=1.2 μg/mL against exogenous cytoplasmic reactive oxygen species, followed by the water-methanolic (IC50=4.5 μg/mL, methylene chloride (IC50=5.9 μg/mL, ethyl acetate (IC50=8.0 μg/mL, 4-nerolidylcatechol (IC50=8.6 μg/mL, and the sterol fractions (IC50>12.5 μg/mL. Vitamin C, the positive control used in this assay, presented IC50 value equivalent to 1.7 μg/mL. 4-Nerolidylcatechol (IC50=0.4 μg/mL and methylene chloride fraction (IC50=2.3 μg/mL presented considerable cytotoxicity probably because of the presence of an o-quinone, an auto-oxidation by product of the catechol. Polar compounds, present in the ethanol extract, appear to increase the solubility and stability of the major active constituent, acting synergistically with 4-nerolidylcatechol, improving its pharmacokinetic parameters and increasing significantly its antioxidant activity which, in turn, suggests that the aqueous-ethanolic extract, used in folklore medicine, is safe and effective.
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Lethal concentration (CL50 of un-ionized ammonia for pejerrey larvae in acute exposure
Directory of Open Access Journals (Sweden)
Piedras Sérgio Renato Noguez
2006-01-01
Full Text Available Ammonia results from decomposition of effluents organic matter, e.g. feed wastes and fish faeces. Its un-ionized form can be toxic because diffuses easily through fish respiratory membranes, damaging gill epithelium and impairing gas exchanges. The objective of this work was determining the 96-hour CL50 of un-ionized ammonia for newly hatched pejerrey Odontesthes bonariensis larvae. Trials were set up completely randomized design, with three different concentration of un-ionized ammonia (0.57, 0.94, and 1.45 mg L-1 NH3-N and a control treatment (n = 3. Experimental units were 20-L, aerated aquaria stocked with 20 larvae (average weight 3.9 mg. Pejerrey larvae exposed to un-ionized ammonia during 96 hours present 50% mortality at 0.71 mg L-1 NH3-N.
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Energy Technology Data Exchange (ETDEWEB)
Jangi, M.S.; Ibrahim, H. (Faculty of Health Sciences, Universiti Kebangsaan, Malysia, Bangi, Selangor)
1983-05-01
A total of 24 isolates of Bacillus thuringiensis (Berliner), resistant to a ..gamma..-radiation dose of 100 krad, were screened for their toxicity to larval silkworms, Bombyxmori(L.), and 15 of them were subsequently tested for their toxicity to larval diamond-back moth, Plutella xylostella(L.). The LC/sub 50/'s of these isolates to B. mori ranged from 1.6 X 10/sup 5/ to 6.0 X 10/sup 3/ spores/mL or from 5.9 to 0.3 ..mu..g cellular protein/mL. The irradiation treatment produced isolates which were significantly more toxic to P. xylostella (LC/sub 50/ < 8.1 X 10/sup 4/ spores/mL or 3.7 ..mu..g cellular protein/mL) and/ or less toxic to B. mori (LC/sub 50/ > 2.3 X 10/sup 4/ spores/mL or 1.0 ..mu..g cellular protein/mL) than the parent commercial strain.
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L1{sub 0} phase formation in ternary FePdNi alloys
Energy Technology Data Exchange (ETDEWEB)
Montes-Arango, A.M. [Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA 02115 (United States); Bordeaux, N.C. [Department of Chemical Engineering, Northeastern University, Boston, MA 02115 (United States); Liu, J.; Barmak, K. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027 (United States); Lewis, L.H., E-mail: lhlewis@neu.edu [Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA 02115 (United States); Department of Chemical Engineering, Northeastern University, Boston, MA 02115 (United States)
2015-11-05
Metallurgical routes to highly metastable phases are required to access new materials with new functionalities. To this end, the stability of the tetragonal chemically ordered L1{sub 0} phase in the ternary Fe–Pd–Ni system is quantified to provide enabling information concerning synthesis of L1{sub 0}-type FeNi, a highly attractive yet highly elusive advanced permanent magnet candidate. Fe{sub 50}Pd{sub 50−x}Ni{sub x} (x = 0–7 at%) samples were arc-melted and annealed at 773 K (500 °C) for 100 h to induce formation of the chemically ordered L1{sub 0} phase. Coupled calorimetry, structural and magnetic investigations allow determination of an isothermal section of the ternary Fe–Pd–Ni phase diagram featuring a single phase L1{sub 0} region near the FePd boundary for x < 6 at%. It is demonstrated that increased Ni content in Fe{sub 50}Pd{sub 50−x}Ni{sub x} alloys systematically decreases the order-disorder transition temperature, resulting in a lower thermodynamic driving force for the ordering phase transformation. The Fe{sub 50}Pd{sub 50−x}Ni{sub x} L1{sub 0} → fcc disordering transformation is determined to occur via a two-step process, with compositionally-dependent enthalpies and transition temperatures. These results highlight the need to investigate ternary alloys with higher Ni content to determine the stability range of the L1{sub 0} phase near the FeNi boundary, thereby facilitating kinetic access to the important L1{sub 0} FeNi ferromagnetic phase. - Highlights: • Chemical ordering in FePdNi enhances intrinsic and extrinsic magnetic properties. • 773 K annealed FePdNi alloys studied show a stable L1{sub 0} phase for Ni ≤ 5.2 at%. • Chemical disordering in FePdNi occurs by a previously unreported two-step process. • Ni additions to FePd dramatically decrease the chemical order-disorder temperature. • The chemical-ordering transformation kinetics are greatly affected by Ni content.
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Magnetic properties and configuration of Fe{sub 50}Pt{sub 50*x}Rh{sub x} films
Energy Technology Data Exchange (ETDEWEB)
Fenske, Jochen; Lott, Dieter; Schreyer, Andreas [Helmholt-Zentrum, Geesthacht (Germany); Schmidt, Wolfgang; Schmalzl, Karin [IFF Forschungszentrum, Juelich (Germany); JCNS at ILL (France); Mankey, Gary J. [MINT Center, University of Alabama (United States); Klose, Frank [Ansto, Bragg Institute (Australia); Tartakowskaya, Helena [Institute for Magnetism, National Accademy of Scinece (Ukraine)
2011-07-01
Ordered FePt alloys with L1{sub 0} structure are known as materials with FM order and a high magnetic moment of Fe providing a large magnetization. The large atomic number of Pt on the other hand results in a high magnetic anisotropy. If grown in thin films, the high anisotropy often results in perpendicular magnetization which is the preferred orientation for current magnetic recording media. One way to control the magnetic properties in these materials is through the introduction of a third element into the crystal matrix e.g. Rh. When Rh is added to replace Pt in the equiatomic alloy, new magnetic phases emerge. Here we present neutron diffraction studies on the magnetic properties of different 200nm thick Fe{sub 50}Pt{sub 50*x}Rh{sub x} films in dependence of the temperature and external magnetic fields. Additional resonant x-ray measurements on the Fe and Pt absorption edges provide additional information about the magnetic moments on these sites.
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Directory of Open Access Journals (Sweden)
Amira S. Wanas
2016-03-01
Full Text Available The n-hexane extracted volatile fraction of high potency Cannabis sativa L (Cannabaceae . was assessed in vitro for antifungal, antibacterial and antileishmanial activities. The oil exhibited selective albeit modest, antifungal activity against Cryptococcus neoformans with an IC 50 value of 33.1 µg/mL. Biologically-guided fractionation of the volatile fraction resulted in the isolation of three major compounds (1-3 using various chromatographic techniques. The chemical structures of the isolated compounds were identified as α-humulene (1, b -caryophyllene (2 and caryophyllene oxide (3 using GC/FID, GC/MS, 1D- and 2D-NMR analyses, respectively. Compound 1 showed potent and selective antifungal activity against Cryptococcus neoformans with IC 50 and MIC values of 1.18 m g/mL and 5.0 m g/mL respectively. Whereas compound 2 showed weak activity (IC 50 19.4 µg/mL, while compound 3 was inactive against C. neoformans.
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International Nuclear Information System (INIS)
Bovi, Jose Eduardo
2000-01-01
The research had the aim of evaluating the effects of low doses of Cobalt-60 gamma radiation on seeds of radish (Raphanus sativus L.) cultiva Champion, cultivars Nantes Forto (european origin) and Brasilia (Rio Grande do Sul origin) carrot (Daucus carota L. var. sativus (Hoffm.) Thell), and red beet (Beta vulgaris L.) cultivar Tall Top Early Wonder before sowing, its effects on plant growth, on the yield and roots storage of two tillages: with sowing in the same day of radiation and six days after radiation seeds. The data showed that the seeds radiation did not interfered negatively on plants growth, and the species presented differences as roots production and doses on both plantation: radish with 5,0 Gy and 2,5 Gy doses respectively to the first and the second sowings, Brasilia carrot with 2,5 Gy dose to both sowings. Nantes carrot with 2,5 Gy and 5,0 Gy respectively to the first and the second sowings, and beet with 7,5 Gy and 5,0 Gy respectively to the first and the second plantations. There is not statistics difference by Tukey test (5% and 1%) and none relation between seeds radiation and loss weight on roots storage. (author)
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Romance of Leadership as a Leader Emergence Predictor
2008-03-01
personality trait that has shown potential in predicting leader emergence is locus of control (Anderson & Schneier, 1978; Johnson, Luthans ...leaderless group. In general terms, it appears that an individual’s view of leaders (and the inspiration to become one), could possibly affect his or... inspire them to “step up” and become leaders themselves, not at all dissimilar from the natural tendency to mimic behaviors of those held in high
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Energy Technology Data Exchange (ETDEWEB)
Ridolfi, A.; Villaamil, E. C.; Ravenna, A.; Sassone, A. H.; Alvarez, G.; Olmos, V.; Lopez, C. M.; Roses, O. E. [Buenos Aires Univ., Buenos Aires (Argentina). Facultad de Farmacia y Bioquimica, Catedra de Toxicologia y Quimica Legal
2001-06-01
Study of CL50 for Heptachlor in the autoctonous fish from Argentina Cnesterodon Decemmaculatus, exposed to {gamma} -HCH and Heptachlor (variable concentration of Heptachlor and fixed concentration of {gamma} -HCH). LC50 after 24, 48, 72 and 96 hours fish Cnesterodon decemmaculatus to exposure to Heptachlor alone in variable quantities (H) and in presence of a fixed quantity of 80 ng/ml {gamma} -HCH (H+{gamma}H) were studied. A semi-static system was used. Applied tests were: a) acceptance of the lot; b) preliminary test, and c) final test. Control groups (ethanol, water and {gamma}-HCH alone) were added. CL50 values group H after 24, 48, 72 and 96 hours of exposure were 42, 30, 30 and 27 ng/ml, and in group H+{gamma}H, at the same periods of time, were 17, 8, 6 and 4 ng/ml, respectively. LC50 in H+{gamma}H group was among 2.47 e 6.75 times higher than in H group; differences between groups were significants (p < 0.005). A potentiation effect of Heptaclor in presence of {gamma}-HCH is supposed to be developed. [Italian] L'uso di composti chimici in agricoltura ha causato la contaminazione del suolo e delle acque comprese quelle sotterranee, a causa dell'uso diretto di pesticidi e fertilizzanti alcune sostanze chimiche possono persistere per molti anni nell'ambiente (Ecobichon, D. J. 1996). Le fonti di esposizioni ai pesticidi sono diverse. Il clearence dell'ettacloro e' rapido e completo, ed il principale prodotto di accumulo e' il suo metabolita, l'epossido di ettacloro, che persiste nell'ambiente per un periodo di tempo molto piu' lungo. I dati sulla tossicita' di questo metabolita sono paragonabili a quelli dell'ettacloro. La sua tendenza ad accumularsi nel tessuto grasso puo' produrre seri pericoli all'ambiente nel quale e' notevolmente persistente (WHO, 1984). In Argentina l'uso di ettacloro e' stato limitato fin dal 1993 quasi esclusivamente al controllo di insetti terrestri e e
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A novel hyaluronidase produced by Bacillus sp. A50.
Directory of Open Access Journals (Sweden)
Xueping Guo
Full Text Available Hyaluronidases are a family of enzymes that degrade hyaluronic acid (hyaluronan, HA and widely used in many fields. A hyaluronidase producing bacteria strain was screened from the air. 16S ribosomal DNA (16S rDNA analysis indicated that the strain belonged to the genus Bacillus, and the strain was named as Bacillus sp. A50. This is the first report of a hyaluronidase from Bacillus, which yields unsaturated oligosaccharides as product like other microbial hyaluronate lyases. Under optimized conditions, the yield of hyaluronidase from Bacillus sp. A50 could reach up to 1.5×10(4 U/mL, suggesting that strain A50 is a good producer of hyaluronidase. The hyaluronidase (HAase-B was isolated and purified from the bacterial culture, with a specific activity of 1.02×10(6 U/mg protein and a yield of 25.38%. The optimal temperature and pH of HAase-B were 44°C and pH 6.5, respectively. It was stable at pH 5-6 and at a temperature lower than 45°C. The enzymatic activity could be enhanced by Ca2+, Mg2+, or Ni2+, and inhibited by Zn2+, Cu2+, EDTA, ethylene glycol tetraacetic acid (EGTA, deferoxamine mesylate salt (DFO, triton X-100, Tween 80, or SDS at different levels. Kinetic measurements of HAase-B towards HA gave a Michaelis constant (Km of 0.02 mg/mL, and a maximum velocity (Vmax of 0.27 A232/min. HAase-B also showed activity towards chondroitin sulfate A (CSA with the kinetic parameters, Km and Vmax, 12.30 mg/mL and 0.20 A232/min respectively. Meanwhile, according to the sequences of genomic DNA and HAase-B's part peptides, a 3,324-bp gene encoding HAase-B was obtained.
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Morgan, T J; Koch, D; Morris, D; Clague, A; Purdie, D M
2001-10-01
We investigated whether red cell 2,3-diphosphoglycerate (2,3-DPG) concentrations are reduced in critical illness, whether acidaemia, hypophosphataemia or anaemia influence 2,3-DPG, and whether there is any net effect on in vivo P50. Twenty healthy, non-smoking, male volunteers were compared with 20 male intensive care patients with APACHE 2 scores >20 on the preceding day. Those transfused in this time were excluded. Venous red cell 2,3-DPG concentrations were measured in both groups. In the patient group, routine multichannel biochemical profile and arterial blood gas analysis were also performed and in vivo P50 calculated. The mean 2,3-DPG concentration was significantly lower in the patient group than in the controls (4.2+/-1.3 mmol/l vs 4.9+/-0.5 mmol/l, P=0.016). The patients were well oxygenated (lowest arterial PO2=75 mm Hg) and showed a tendency to acidaemia (median pH 7.37, range 7.06 to 7.48) and anaemia (median haemoglobin concentration 113 g/l, range 89 to 154 g/l). By linear regression of patient data, pH had a significant effect on 2,3-DPG concentrations (r=0.6, P=0.011). Haemoglobin and phosphate concentrations did not, but there were few abnormal phosphate values. There was no correlation between 2,3-DPG concentrations and in vivo P50 (r2 < or = 0.08). We conclude that 2,3-DPG concentrations were reduced in a broad group of critically ill patients. Although this would normally reduce the P50, the reduction was primarily linked with acidaemia, which increases the P50. Overall, there was no net effect on the P50 and thus no affinity-related decrease in tissue oxygenation.
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Corrosion behavior of amorphous and crystalline Cu50Ti50 and Cu50Zr50 alloys
International Nuclear Information System (INIS)
Naka, M.; Hoshimoto, K.; Masumoto, T.
1978-01-01
Corrosion rates and anodic polarization curves of amorphous and crystalline Cu 50 Ti 50 and Cu 50 Zr 50 alloys have been examined in various acidic, neutral and alkaline solutions. The amorphous alloys are very stable in acidic and alkaline solutions, but unstable in agressive chloride solutions. The corrosion resistance of these amorphous alloys is higher than that of the crystallized alloys. The high corrosion resistance of amorphous alloys is attributable to the high chemical homogeneity of amorphous alloys without localized crystalline defects such as precipitates, segregates, grain boundaries, etc. Metalloid elements play an important role in the corrosion behavior of amorphous alloys; the addition of phosphorus to amorphous Cu-Ti alloy greatly increases the corrosion resistance, even in 1N HCl. (Auth.)
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CERN receives early 50th anniversary present from Swiss Confederation
2003-01-01
"Swiss President Pascal Couchepin announced Wednesday 4 June an early 50th birthday present from the Swiss Confederation to CERN. Switzerland has decided to offer the laboratory the 'Palais de l'Equilibre', a landmark building designed by Geneva architects for Switzerland's 2002 national exhibition" (1/2 page).
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Cucumis sativus L, Nasim variety
African Journals Online (AJOL)
... practice for reducing water consumption and improving product quality. ... Since cucumbers (Cucumis sativus L, Nasim variety) is considered as the main and ... to a significant yield increase (P<0.001), while MAD of 50% had the least yield.
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Life History and Risk of Death after 50: A Survival Analysis for Europe.
Nicińska, Anna; Kalbarczyk-Stęclik, Małgorzata
2015-12-01
RÉSUMÉ Dans notre étude nous avons examiné l'influence des événements du passé des individus sur le risque de décès des Européens âgés de plus de 50 ans, en contrôlant autres variables pertinentes. Notre analyse était basée sur les données d'entretiens biographiques rétrospectifs, les données d'entretiens réguliers au suivi longitudinal et celles d'entretiens de fin de vie de l'Enquête européenne SHARE sur la santé, le vieillissement et la retraite en Europe. En particulier, nous relevons l'état de santé auto-déclaré pendant l'enfance; les périodes de pauvreté, de faim et de mauvaise santé éprouvées dans le passé; et aussi l'histoire des soins de santé, y compris les soins dentaires, les analyses de sang et les mesures de pression artérielle. Ces informations, avec l'age, le sexe, l'état de santé subjectif et objectif, et d'autres facteurs socio-démographiques, permettent d'expliquer le risque de décès. L'analyse de survie, en contrôlant des variables pertinentes, montre que les événements du passé ont un impact significatif sur le risque de décès des Européens âgés de plus de 50 ans.
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Directory of Open Access Journals (Sweden)
Alaleh Mottaghian
2016-03-01
Full Text Available To investigate the effect of organic fertilizer applications on yield and competition indices of basil (Ocimum basilicum L. in different combinations of intercropping with sesame (Sesamum indicum L., an experiment was carried out in split plot based on randomized complete block design with three replicates in 2011. The main plots were six fertilizer treatments consisted of 20 and 40 Mg ha-1 of vermicompost and sewage sludge plus 50% recommended chemical fertilizer, chemical fertilizer alone (100 kg ha-1 of urea, triple super phosphate and potassium sulfate and control (no fertilizer application. Subplots were different planting ratios (sole cropping of basil and sesame, 75% + 25%, 50% + 50 %, 25% + 75% of basil+sesame. In this experiment, the 25% basil+75% sesame and 50% basil + 50%sesame under40 Mg. ha-1 of enriched sewage sludge application had the highest economical yield (up to 3097.47 kg ha-1 with a land equivalent ratio (up to 1.24. According to the aggressivity coefficient estimates of two plant species basil incombination of 25% basil + 75% sesame and sesame in 50% basil + 50% sesame and 75% basil + 25% sesame under organic fertilizer application would be dominant species competitave in ranges of 0.12 to 0.30 and 0.11 to 0.57, respectively.
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Directory of Open Access Journals (Sweden)
Sorina CORBU
2006-05-01
Full Text Available The present experiment is a research on the effect of the allelopathic substances in the leaves of the black nut (Juglans nigra L. over the species of white mustard (Sinapis alba L. and the moon – raddish (Raphanus sativus L.. We have prepared a watery extract of a concentration of 5, 15, 25, 50, 75 and 100% from the leaves in different seasons (spring, autumn and winter. The watery extract presents an inhibitory effect over the germination and growth of the plants subdued to experiments, especialy over the leaves collected in spring.
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Jakobsen, Oyvind M; Brautaset, Trygve; Degnes, Kristin F; Heggeset, Tonje M B; Balzer, Simone; Flickinger, Michael C; Valla, Svein; Ellingsen, Trond E
2009-02-01
Aspartokinase (AK) controls the carbon flow into the aspartate pathway for the biosynthesis of the amino acids l-methionine, l-threonine, l-isoleucine, and l-lysine. We report here the cloning of four genes (asd, encoding aspartate semialdehyde dehydrogenase; dapA, encoding dihydrodipicolinate synthase; dapG, encoding AKI; and yclM, encoding AKIII) of the aspartate pathway in Bacillus methanolicus MGA3. Together with the known AKII gene lysC, dapG and yclM form a set of three AK genes in this organism. Overexpression of dapG, lysC, and yclM increased l-lysine production in wild-type B. methanolicus strain MGA3 2-, 10-, and 60-fold (corresponding to 11 g/liter), respectively, without negatively affecting the specific growth rate. The production levels of l-methionine (less than 0.5 g/liter) and l-threonine (less than 0.1 g/liter) were low in all recombinant strains. The AK proteins were purified, and biochemical analyses demonstrated that they have similar V(max) values (between 47 and 58 micromol/min/mg protein) and K(m) values for l-aspartate (between 1.9 and 5.0 mM). AKI and AKII were allosterically inhibited by meso-diaminopimelate (50% inhibitory concentration [IC(50)], 0.1 mM) and by l-lysine (IC(50), 0.3 mM), respectively. AKIII was inhibited by l-threonine (IC(50), 4 mM) and by l-lysine (IC(50), 5 mM), and this enzyme was synergistically inhibited in the presence of both of these amino acids at low concentrations. The correlation between the impact on l-lysine production in vivo and the biochemical properties in vitro of the individual AK proteins is discussed. This is the first example of improving l-lysine production by metabolic engineering of B. methanolicus and also the first documentation of considerably increasing l-lysine production by overexpression of a wild-type AK.
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Gillner, Danuta; Armoush, Nicola; Holz, Richard C; Becker, Daniel P
2009-11-15
The dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) is a critical bacterial enzyme for the construction of the bacterial cell wall. A screen biased toward compounds containing zinc-binding groups (ZBG's) including thiols, carboxylic acids, boronic acids, phosphonates and hydroxamates has delivered a number of micromolar inhibitors of DapE from Haemophilus influenzae, including the low micromolar inhibitor L-captopril (IC(50)=3.3 microM, K(i)=1.8 microM). In vitro antimicrobial activity was demonstrated for L-captopril against Escherichia coli.
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Cross, Kristen E; Mercante, Jeffrey W; Benitez, Alvaro J; Brown, Ellen W; Diaz, Maureen H; Winchell, Jonas M
2016-07-01
Legionnaires' disease is a severe respiratory disease that is estimated to cause between 8,000 and 18,000 hospitalizations each year, though the exact burden is unknown due to under-utilization of diagnostic testing. Although Legionella pneumophila is the most common species detected in clinical cases (80-90%), other species have also been reported to cause disease. However, little is known about Legionnaires' disease caused by these non-pneumophila species. We designed a multiplex real-time PCR assay for detection of all Legionella spp. and simultaneous specific identification of four clinically-relevant Legionella species, L. anisa, L. bozemanii, L. longbeachae, and L. micdadei, using 5'-hydrolysis probe real-time PCR. The analytical sensitivity for detection of nucleic acid from each target species was ≤50fg per reaction. We demonstrated the utility of this assay in spiked human sputum specimens. This assay could serve as a tool for understanding the scope and impact of non-pneumophila Legionella species in human disease. Published by Elsevier Inc.
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Théâtre les 50
2011-01-01
Le Théâtre Les 50 de Saint Jean de Gonville propose : ARAGON CHANTÉ ET PARLÉ : Ferré, Ferrat, Brassens LOUIS ARAGON, écrivain et poète français ... Cofondateur de la revue Libération en 1919, avec André Breton et Philippe Soupault, Aragon publia l'un des meilleurs romans surréalistes, Le Paysan de Paris (1926). Lié à la Résistance durant toute l'occupation, Aragon participa après la guerre aux activités du Parti communiste français. Son œuvre poétique fut marquée par son amour pour sa compagne, Elsa Triolet. À partir de la fin des années 1950, nombre de ses poèmes ont été mis en musique et chantés notamment par Jean Ferrat et Léo Ferré, contribuant à faire connaître son œ...
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Energy Technology Data Exchange (ETDEWEB)
Hartvig, P; Tedroff, J; Lindner, K J; Bjurling, P; Chang, C W; Laangstroem, B [Uppsala Univ. (Sweden); Tsukada, H [Central Research Lab., Hamamatsu Photonics Shizuoka, Osaka (Japan); Watanabe, Y [Dept. of Neuroscience, Osaka Bioscience Inst., Osaka (Japan)
1993-01-01
The regional brain kinetics following 5-hydroxy-L-([beta]-11 C)tryptophan and L-([beta]-11 C)DOPA intravenous injection was measured in twelve Rhesus monkeys using positron emission tomography (PET). The radiolabelled compounds were also injected together with various doses of unlabelled 5-hydroxy-L-tryptophan or L-DOPA. The radioactivity accumulated in the striatal region and the rate of increased utilization with time was calculated using a graphical method with back of the brain as a reference region. The rate constants for decarboxylation were 0.0070 [+-] 0.0007 (S. D) and 0.0121 [+-] 0.0010 min[sup -1] for 5-hydroxy-L-([beta]-11 C)tryptophan and L-([beta]-11 C)DOPA, respectively. After concomitant injection with unlabelled 5-hydroxy-L-tryptophan, the rate constant of 5-hydroxy-L-([beta]-11 C)tryptophan decreased dose-dependently and a 50 percent reduction was seen with a dose of about 4 mg/kg of unlabelled compound. A decreased utilization rate of L-([beta]-11 C)DOPA was seen only after simultaneous injection of 30 mg/kg of either L-DOPA or 5-hydroxy-L-tryptophan. This capacity limitation was most likely interpreted as different affinity of the striatal aromatic amino acid decarboxylase for L-DOPA and 5-hydroxy-L-tryptophan, respectively.
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Combined toxicity of microcystin-LR and copper on lettuce (Lactuca sativa L.).
Cao, Qing; Steinman, Alan D; Wan, Xiang; Xie, Liqiang
2018-05-10
Microcystins and copper commonly co-exist in the natural environment, but their combined toxicity remains unclear, especially in terrestrial plants. The present study investigated the toxicity effects of microcystin-LR (0, 5, 50, 500, 1000 μg L -1 ) and copper (0, 50, 500, 1000, 2000 μg L -1 ), both individually and in mixture, on the germination, growth and oxidative response of lettuce. The bioaccumulation of microcystin-LR and copper was also evaluated. Results showed that the decrease in lettuce germination induced by copper alone was not significantly different from that induced by the mixture, and the combined toxicity assessment showed a simple additive effect. Lettuce growth was not significantly reduced by microcystin-LR alone, whereas it was significantly reduced by copper alone and the mixture when copper concentration was higher than 500 μg L -1 . High concentrations of microcystin-LR (1000 μg L -1 ) and copper (≥50 μg L -1 ),as well as their mixture (≥50 + 500 μg L -1 ), induced oxidative stress in lettuce. A synergistic effect on the growth and antioxidative system of lettuce was observed when exposed to low concentrations of the mixture (≤50 + 500 μg L -1 ), whereas an antagonistic effect was observed at high concentrations (≥1000 + 2000 μg L -1 ). Moreover, the interaction of microcystin-LR and copper can increase their accumulation in lettuce. Our results suggest that the toxicity effects of microcystin-LR and copper are exacerbated when they co-exist in the natural environment at low concentrations, which not only negatively affects plant growth but also poses a potential risk to human health via the food chain. Copyright © 2018. Published by Elsevier Ltd.
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Energy Technology Data Exchange (ETDEWEB)
Poirier, M.
2011-06-15
Tank 50H is the feed tank for the Saltstone Production Facility (SPF). At present, Tank 50H contains two standard slurry pumps and two Quad Volute slurry pumps. Current requirements and mixing operation is to run three pumps for one hour prior to initiating a feed transfer to SPF. Savannah River Site (SRS) Liquid Waste would like to move one or both of the Quad Volute pumps from Tank 50H to Tank 51H to replace pumps in Tank 51H that are failing. In addition, one of the standard pumps in Tank 50H exhibits high seal leakage and vibration. SRS Liquid Waste requested Savannah River National (SRNL) to conduct a study to evaluate the feasibility of mixing the contents of Tank 50H with one to three standard slurry pumps. To determine the pump requirements to blend miscible and immiscible liquids in Tank 50H, the author reviewed the pilot-scale blending work performed for the Salt Disposition Integration Project (SDIP) and the technical literature, and applied the results to Tank 50H to determine the number, size, and operating parameters needed to blend the tank contents. The conclusions from this analysis are: (1) A single rotating standard slurry pump (with a 13.6 ft{sup 2}/s U{sub 0}D) will be able to blend miscible liquids (i.e., salt solution) in Tank 50H within 4.4 hours. (2) Two rotating standard slurry pumps will be able to blend miscible liquids in Tank 50H within 3.1 hours. (3) Three rotating standard slurry pumps will be able to blend miscible liquids in Tank 50H within 2.5 hours. (4) A single rotating standard slurry pump (with a 13.6 ft{sup 2}/s U{sub 0}D) will disperse Isopar L{reg_sign} droplets that are less than or equal to 15 micron in diameter. If the droplets are less than 15 micron, they will be dispersed within 4.4 hours. Isopar L{reg_sign} provides a lower bound on the maximum size of droplets that will be dispersed by the slurry pumps in Tank 50H. (5) Two rotating standard slurry pumps will disperse Isopar L{reg_sign} droplets less than 15 micron
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Xanthatin and xanthinosin from the burs of Xanthium strumarium L. as potential anticancer agents.
Ramírez-Erosa, Irving; Huang, Yaoge; Hickie, Robert A; Sutherland, Ronald G; Barl, Branka
2007-11-01
Xanthatin and xanthinosin, 2 sesquiterpene lactones isolated from the burs of Xanthiun strumarium L. (cocklebur), showed moderate to high in vitro cytotoxic activity in the human cancer cell lines WiDr ATCC (colon), MDA-MB-231 ATCC (breast), and NCI-417 (lung). Xanthatin and xanthinosin were purified as the result of a multi-screening bioassay-guided study of wild plant species of the family Asteraceae, collected from various sites in Saskatchewan, Canada. Seventy-five extracts at a single concentration of 100 microg/mL were evaluated for in vitro cytotoxicity to the human cancer cell lines used. The chloroform extract of Carduus nutans L. (nodding thistle) aerial parts (IC50, 9.3 microg/mL) and the hexane extract of Echinacea angustifolia DC. (narrow-leaved purple coneflower) root (IC50, 4.0 microg/mL) were moderately to highly cytotoxic to the lung cancer cell line. The chloroform extracts of X. strumarium L. burs and Tanacetum vulgare L. (tansy) aerial parts exhibited the highest cytotoxicity for all cell lines tested; their IC50 values, obtained from multidose testing, ranged from 0.1 to 6.2 microg/mL (X. strumarium) and from 2.4 to 9.1 microg/mL (T. vulgare). Further purification of the chloroform fraction of X. strumarium yielded xanthatin and xanthinosin in high yields. This is the first time that these compounds have been reported in the burs of X. strumarium. Their IC50 values are also reported herein.
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Directory of Open Access Journals (Sweden)
Katarzyna Targońska
2011-07-01
Full Text Available This study was aimed at determining the effect of stocking density on growth, survival and development of asp Aspius aspius (L., ide Leuciscus idus (L. and chub Leuciscus cephalus (L. larvae, reared under laboratory conditions. Fish larvae were obtained during artificial reproduction. The larvae were fed ad libitum with freshly hatched Artemia sp. nauplii. Eight density variants from 50 to 400 individuals per 1 L (at the interval of 50 individuals L–1 were tested. The initial rearing was carried out for 21 days at 25°C in a recirculation system especially designed for that purpose consisting of 16 tanks with a capacity of 1 L each. The fastest growth rate for all three species, expressed as the greatest average total length, weight and most advanced ontogenetic stage at the end of the experiment was obtained at the lowest stocking density. Fish from other treatments, particularly at densities exceeding 150 individuals L–1, were characterized by similar body sizes and the same ontogenetic stage on the last day of rearing. The recorded differences in the length of larvae among treatments became visible during the first (asp or third (chub, ide week of rearing. No effects of stocking density on larval mortality were found during the experiment.
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Lee, Yoen Jung; Choi, In-Kwon; Sheen, Yhun Yhong; Park, Sue Nie; Kwon, Ho Jeong
2012-01-01
To identify specific biomarkers generated upon exposure of L5178Y mouse lymphoma cells to carcinogens, 2-DE and MALDI-TOF MS analysis were conducted using the cellular proteome of L5178Y cells that had been treated with the known carcinogens, 1,2-dibromoethane and O-nitrotoluene and the noncarcinogens, emodin and D-mannitol. Eight protein spots that showed a greater than 1.5-fold increase or decrease in intensity following carcinogen treatment compared with treatment with noncarcinogens were selected. Of the identified proteins, we focused on the candidate biomarker ERM-binding phosphoprotein 50 (EBP50), the expression of which was specifically increased in response to treatment with the carcinogens. The expression level of EBP50 was determined by western analysis using polyclonal rabbit anti-EBP50 antibody. Further, the expression level of EBP50 was increased in cells treated with seven additional carcinogens, verifying that EBP50 could serve as a specific biomarker for carcinogens. PMID:22434383
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Profile of NF-κBp(65/NFκBp50) among prostate specific antigen sera levels in prostatic pathologies.
Bouraoui, Y; Ben Jemaa, A; Rodriguez, G; Ben Rais, N; Fraile, B; Paniagua, R; Sellemi, S; Royuela, M; Oueslati, R
2012-10-01
The aim of this work was to characterise the immunoexpression of NF-κB (p50/p65) in human prostatic pathologies and to study its profiles of activation among sera prostate specific antigen antigen (PSA) according the three groups: 0-4ng/mL, 4-20ng/mL and >20ng/mL. Twenty-four men with benign prostate hyperplasia (BPH); 19 men with prostate cancer (PC) and five men with normal prostates (NP). Immunohistochemical and western blot analysis was performed. Serum levels of PSA were assayed by immulite autoanalyser. In BPH and PC samples, immunoexpressions were observed for NF-κBp65 and NF-κBp50; while in NP samples, only were detected NF-κBp50. PC samples showed immunoreactions to NF-κBp65 and NF-κBp50 more intense (respectively 24.18±0.67 and 28.23±2.01) than that observed in BPH samples (respectively18.46±2.04 and 18.66±1.59) with special localisation in the nucleus. Different profiles of NF-κBp65 immunoexpressions were observed and BPH patients with sera PSA levels between 0-4ng/mL presented a significant weak percentage compared to BPH patients with sera PSA levels between 4-20ng/mL and >20ng/mL. No immunoreactions to NF-κBp65 were observed in PC patients with sera PSA levels between 4-20ng/mL. The sensibility of both NF-κB and PSA to inflammation allowed confirming the relationship between these two molecules and its involvement in prostatic diseases progression (inflammatory and neoplasic). Copyright © 2011 Elsevier Masson SAS. All rights reserved.
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Directory of Open Access Journals (Sweden)
Goudarz Ahmadvand
2016-03-01
Full Text Available Intercropping is considered for increasing and stability of yield in per unit. In order to study the effects of soybean (Glycine max L. and millet (Panicum miliaceum L. replacement intercropping on agronomic traits, diversity of weeds and soil biological activity, an experiment was conducted at the Research Station of Agricultural Faculty, of Bu-Ali Sina University, in 2014. The experiment was carried out as a randomized complete block design with three replications. The replacement intercropping series consisted of monoculture of soybean, monoculture of millet, 75% soybean+ 25% millet, 50% soybean+ 50% millet and 25% soybean+ 75% millet. The results showed that the highest seed yield of 219.8 and 171.9 gm-2 belonged to monoculture of soybean and monoculture of millet, respectively. Intercropping reduced maximum leaf area index of soybean and millet but leaf chlorophyll content of soybean and millet were increased. The highest number of pods per plant, number of seeds per plant in soybean and panicle number per plant in millet were obtained in 50S:50M ratio. Mean soil respiration rate in intercropping treatments was 4 and 8 % higher than the monoculture of soybean and millet, respectively. Intercropping patterns of 50S:50M and 25S:75M were successful in reducing weed plant density and diversity in comparison with soybean monoculture. Results showed that in all intercropping treatments, land equivalent ratio was more than one. Maximum value of land equivalent ratio (2.20 was achieved in 50S:50M treatment. Soybean and millet intercropping at different levels of replacement, didn’t have actual yield loss. Calculating the aggressivity showed that millet was more dominate than soybean. The maximum relative crowding coefficient of soybean was observed in 75S:25M, however that of millet was obtained in 25S:75M and 50S:50M intercroppings indicating that millet is more competitor than soybean.
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Amylase Production from Thermophilic Bacillus sp. BCC 021-50 Isolated from a Marine Environment
Directory of Open Access Journals (Sweden)
Altaf Ahmed Simair
2017-06-01
Full Text Available The high cost of fermentation media is one of the technical barriers in amylase production from microbial sources. Amylase is used in several industrial processes or industries, for example, in the food industry, the saccharification of starchy materials, and in the detergent and textile industry. In this study, marine microorganisms were isolated to identify unique amylase-producing microbes in starch agar medium. More than 50 bacterial strains with positive amylase activity, isolated from marine water and soil, were screened for amylase production in starch agar medium. Bacillus sp. BCC 021-50 was found to be the best amylase-producing strain in starch agar medium and under submerged fermentation conditions. Next, fermentation conditions were optimized for bacterial growth and enzyme production. The highest amylase concentration of 5211 U/mL was obtained after 36 h of incubation at 50 °C, pH 8.0, using 20 g/L molasses as an energy source and 10 g/L peptone as a nitrogen source. From an application perspective, crude amylase was characterized in terms of temperature and pH. Maximum amylase activity was noted at 70 °C and pH 7.50. However, our results show clear advantages for enzyme stability in alkaline pH, high-temperature, and stability in the presence of surfactant, oxidizing, and bleaching agents. This research contributes towards the development of an economical amylase production process using agro-industrial residues.
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Purification and characterization of camel liver L-asparaginase ...
African Journals Online (AJOL)
L-asparaginase from camel liver was isolated and purified by heat denaturation followed by QAE-Sephadex A-50 column chromatography and SP-Sepharose column chromatography. The purified camel liver L-asparaginase had a molecular weight of 180 kDa (consistent with a homotetramer) and a pI value of 8.6.
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Synthesis of L-[35S] homocysteine thiolactone hydrochloride
International Nuclear Information System (INIS)
Hamacher, K.
1989-01-01
L-[ 35 S]Homocysteine thiolactone has been synthesized by demethylation of L-[ 35 S]Methionine with sodium in liquid ammonia and subsequent lactonisation in acid solution. The radiochemical yield of the carrier added synthesis was in the range of 45 to 50% with a radiochemical purity higher than 96%. (author)
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FIELD TESTING A BEHAVIORAL TEAMWORK ASSESSMENT TOOL WITH U.S. UNDERGRADUATE BUSINESS STUDENTS
Charles J. Hobson; David Strupeck; Andrea Griffin; Jana Szostek; Rajan Selladurai; Anna S. Rominger
2013-01-01
Given the ubiquitous utilization of teams in U.S. workplaces, collegiate schools of business have responded by placing great emphasis on the assessment and development of teamwork skills. Employing a methodology first proposed by Hobson and Kesic (2002) for use in managerial training, this study involved the behavioral assessment of teamwork skills in a sample of 247 undergraduate business students. The evaluation tool consisted of 15 positive and 10 negative teamwork behaviors. A leaderless ...
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Apple snack enriched with L-arginine using vacuum impregnation/ohmic heating technology.
Moreno, Jorge; Echeverria, Julian; Silva, Andrea; Escudero, Andrea; Petzold, Guillermo; Mella, Karla; Escudero, Carlos
2017-07-01
Modern life has created a high demand for functional food, and in this context, emerging technologies such as vacuum impregnation and ohmic heating have been applied to generate functional foods. The aim of this research was to enrich the content of the semi-essential amino acid L-arginine in apple cubes using vacuum impregnation, conventional heating, and ohmic heating. Additionally, combined vacuum impregnation/conventional heating and vacuum impregnation/ohmic heating treatments were evaluated. The above treatments were applied at 30, 40 and 50 ℃ and combined with air-drying at 40 ℃ in order to obtain an apple snack rich in L-arginine. Both the impregnation kinetics of L-arginine and sample color were evaluated. The impregnated samples created using vacuum impregnation/ohmic heating at 50 ℃ presented a high content of L-arginine, an effect attributed primarily to electropermeabilization. Overall, vacuum impregnation/ohmic heating treatment at 50 ℃, followed by drying at 40 ℃, was the best process for obtaining an apple snack rich in L-arginine.
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Tsurugi, K; Collatz, E; Todokoro, K; Wool, I G
1977-06-10
The proteins of the large subunit of rat liver ribosomes were separated into seven groups by stepwise elution from carboxymethylcellulose with LiCl at pH 6.5. Twenty-one proteins (L3, L6, L7', L8, L10, L15, L17, L18, L19, L23', L25, L27', L28, L29, L31, L32, L34, L35, L36, L36', and L37') were isolated from three groups (C60, E60, and F60) by ion exchange chromatography on carboxymethycellulose and by filtration through Sephadex. The amount of protein obtained varied from 0.3 to 25 mg. Nine of the proteins (L6, L8, L18, L27', L28, L29, L34, L36, and L36') had no detectable contamination: the impurities in the others were no greater than 9%. The molecular weight of the proteins was estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate; the amino acid composition was determined.
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Nath, Mala; Jairath, Ruchi; Eng, George; Song, Xueqing; Kumar, Ashok
2005-12-01
New organotin(IV) complexes of the general formula R 3Sn(L) (where R = Me, n-Bu and HL = L-proline; R = Me, Ph and HL = trans-hydroxy- L-proline and L-glutamine) and R 2Sn(L) 2 (where R = n-Bu, Ph and HL = L-proline; R = Ph, HL = trans-hydroxy- L-proline) have been synthesized by the reaction of R nSnCl 4- n (where n = 2 or 3) with sodium salt of the amino acid (HL). n-Bu 2Sn(Pro) 2 was synthesized by the reaction of n-Bu 2SnO with L-proline under azeotropic removal of water. The bonding and coordination behavior in these complexes have been discussed on the basis of IR and 119Sn Mössbauer spectroscopic studies in the solid-state. Their coordination behavior in solution has been discussed with the help of multinuclear ( 1H, 13C and 119Sn) NMR spectral studies. The 119Sn Mössbauer and IR studies indicate that L-proline and trans-hydroxy- L-proline show similar coordination behavior towards organotin(IV) compounds. Pentacoordinate trigonal-bipyramidal and hexacoordinate octahedral structures, respectively, have been proposed for the tri- and diorganotin(IV) complexes of L-proline and trans-hydroxy- L-proline, in which the carboxylate group acts as bidentate group. L-Glutamine shows different coordination behavior towards organotin(IV) compounds, it acts as monoanionic bidentate ligand coordinating through carboxylate and amino group. The triorganotin(IV) complexes of L-glutamine have been proposed to have trigonal-bipyramidal environment around tin. The newly synthesized complexes have been tested for their antiinflammatory and cardiovascular activities. Their LD 50 values are >1000 mg kg -1.
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International Nuclear Information System (INIS)
Stishov, S M; Khvostantsev, L G; Slesarev, V N; Popova, S V; Brazhkin, V V; Dyuzheva, T I; Dzhavadov, L N; Gromnitskaya, E L; Stepanov, G N; Timofeev, Yu A; Dizhur, E M; Venttsel, V A; Voronovskii, A N; Ryzhov, V N; Barabanov, A F; Magnitskaya, M V; Tareeva, E E
2008-01-01
A scientific outreach session of the Physical Sciences Division of the Russian Academy of Sciences (RAS) was held on 23 April 2008 at the Institute for High Pressure Physics, RAS, Troitsk, Moscow region. The session was devoted to the 50th anniversary of the Institute. The following reports were presented: (1) Stishov S M (Institute for High Pressure Physics, RAS, Troitsk, Moscow region) 'The Institute for High Pressure Physics is now 50 (opening address)'; (2) Khvostantsev L G and Slesarev V N (Institute for High Pressure Physics, RAS, Troitsk, Moscow region) 'Large-volume high-pressure devices for physical investigations'; (3) Popova S V, Brazhkin V V and Dyuzheva T I (Institute for High Pressure Physics, RAS, Troitsk, Moscow region) 'Structural phase transitions in highly compressed substances and the synthesis of high-pressure phases'; (4) Dzhavadov L N, Gromnitskaya E L, Stepanov G N and Timofeev Yu A (Institute for High Pressure Physics, RAS, Troitsk, Moscow region) 'Studies of the thermodynamic, elastic, superconducting, and magnetic properties of substances at high pressures'; (5) Dizhur E M, Venttsel V A and Voronovskii A N (Institute for High Pressure Physics, RAS, Troitsk, Moscow region), 'Quantum transport at high pressures'; (6) Ryzhov V N, Barabanov A F, Magnitskaya M V and Tareyeva E E (Institute for High Pressure Physics, RAS, Troitsk, Moscow region) 'Theoretical studies of condensed matter'; (7) Bugakov V I, Antanovich A A, Konyaev Yu S and Slesarev V N (Institute for High Pressure Physics, RAS, Troitsk, Moscow region) 'Designing new construction and superhard materials and related tools'. An abridged version of reports 1-6 is presented below. The Institute for High Pressure Physics is now 50 (opening address), Stishov S M Physics-Uspekhi, 2008, Volume 51, Number 10, Pages 1055-1059 . Large-volume high-pressure devices for physical investigations, Khvostantsev L G and Slesarev V N Physics-Uspekhi, 2008, Volume 51, Number 10, Pages 1059
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Wagner, Sarah A; Schimek, Daniel E
2010-09-01
To determine the effect of IV administration of a bolus of 50% dextrose solution on electrolyte and energy balance and effect of blood collection site on serum electrolyte values in postparturient dairy cows. 24 clinically normal multiparous cows. A bolus of 50% dextrose solution (0.5 L [n=8 cows]), 50% dextrose solution (1.0 L [8]), or saline (0.9% NaCl) solution (1.0 L, control treatment [8]) was administered via jugular venipuncture 5 to 10 days after parturition. Pretreatment and posttreatment blood samples were analyzed for concentrations of calcium, magnesium, phosphorus, potassium, glucose, insulin, beta-hydroxybutyric acid (BHBA), and nonesterified fatty acids. Coccygeal vessel and jugular vein blood samples were obtained prior to treatment, and electrolyte concentrations were compared. Treatment with 50% dextrose decreased phosphorus concentration in serum, compared with the control treatment. Suppression of BHBA and nonesterified fatty acid concentrations following dextrose treatment lasted for dextrose solution may be at risk for hypophosphatemia, and 1 treatment with 0.5 or 1 L of 50% dextrose solution is unlikely to prevent or resolve acetonemia (ketosis). The risk of hypophosphatemia may be underestimated when coccygeal vessel blood samples are used for diagnosis.
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Carnation (Dianthus caryophylus L.).
Nontaswatsri, Chalermsri; Fukai, Seiichi
2006-01-01
Carnation is a valuable crop for the cut flower industry and demand for new and improved varieties is growing. However, genetic transformation of carnations is currently limited because of a lack of efficient routine technique. In this chapter, we present an easy and effective protocol for gene transfer to carnation node explants and subsequent adventitious shoot regeneration. For high-adventitious shoot regeneration, node explants from first to third node of 5- to 8-cm long shoots were cultured on Murashige and Skoog (MS) medium, containing 1.0 mg/Lthidiazuron (TDZ), 0.1 mg/L alpha-napthalenoacetic acid (NAA), 20 g/L sucrose, and 2 g/L Gellan gum for 10 d. Then the explants were cut into 8 radial segments and subcultured onto MS medium, containing 1.0 mg/L BA, 0.1 mg/L NAA, 20 g/L sucrose and 2 g/L Gellan Gum. For effective genetic transformation, 3- to 5-d precultured node explants were submerged in an Agrobacerium suspension for 10 min, then cocultivated on filter paper soaked with water and 50 microM acetosyringone (AS). After cocultivation, the explants were cut into eight radial segments and subcultured onto selection medium until transformed shoots regenerated from the explants.
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Scavenging capacity of strawberry tree (Arbutus unedo L.) leaves on free radicals.
Oliveira, Ivo; Coelho, Valentim; Baltasar, Raquel; Pereira, José Alberto; Baptista, Paula
2009-07-01
Despite strawberry tree (Arbutus unedo L.) leaves had a long use in traditional medicine due to its antiseptic, diuretic, astringent and depurative properties, the potential of their antioxidant activity are still lacking. Our study goals to assess the antioxidant and free radical scavenging potential of water, ethanol, methanol and diethyl ether extracts of A. unedo leaves. Total phenols content was achieved spectrophotometrically using Folin-Ciocalteau reagent with gallic acid as standard. Antioxidant activity was evaluated using three different methods: reducing power of iron (III)/ferricyanide complex assay, scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and scavenging effect on superoxide radicals by using the PMS-NADH-nitroblue tetrazolium system. Ethanol extracts of A. unedo leaves were the highest in reducing power (IC(50) 232.7 microg/mL) and DPPH scavenging effect (IC(50) 63.2 microg/mL) followed by water extracts (with IC(50) of 287.7 and 73.7 microg/mL, respectively); whereas diethyl ether extracts were the lowest. In the scavenging on superoxide radical assay, methanol extracts obtained the best results (IC(50) 6.9 microg/mL). For all the methods tested the antioxidant activity was concentration dependent. In accordance with antioxidant activity, highest total phenols content were found in ethanol, followed by water, methanol and diethyl ether extract. The results indicated that A. unedo leaves are a potential source of natural antioxidants.
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Directory of Open Access Journals (Sweden)
Nilo César do Vale Baracho
2009-12-01
Full Text Available PURPOSE: To evaluate the acute hepatotoxicity of Equisentum arvense L. in rats. METHODS: Fifty Wistar rats were used, these being divided in four groups, one being the control (receiving only water and the other groups receiving graded doses of Equisentum arvense L. (30, 50, and 100mg/kg respectively for 14 days. Blood samples were obtained to determine TGO, TGP, FA, DHL and GT-gamma activities. After that, hepatic tissue samples were collected for the anatomopathologic analysis. RESULTS: The anatomopathologic exam of the hepatic tissue showed organ with preserved lobular structure. In the same way, there was no significant change in the seric activities of the hepatic enzymes when compared to control group. CONCLUSION: The oral treatment with graded doses of Equisentum arvense L. was not able to produce hepatic changes. Further studies are necessary to evaluate the chronic hepatotoxicity of Equisentum arvense L. in rats.OBJETIVO: Investigar a hepatotoxicidade aguda da Equisetum arvense L. em ratos. MÉTODOS: foram utilizados 50 ratos Wistar, os quais foram divididos em quatro grupos, sendo um controle (recebendo apenas água e os outros grupos recebendo doses crescentes de cavalinha (30, 50 e 100mg/Kg, respectivamente por 14 dias. Foram coletadas amostras de sangue para determinação da atividade sérica de TGO, TGP, FA, DHL e gama-GT. Em seguida, foram obtidas amostras de tecido hepático para análise anatomopatológica. RESULTADOS: O exame anatomopatológico de tecido hepático demonstrou órgão com estrutura lobular preservada. Da mesma forma, não houve alteração significativa na atividade sérica das enzimas hepáticas, quando comparado ao grupo controle. CONCLUSÃO: O tratamento com doses crescentes de Equisetum arvense L., não induziu hepatotoxicidade aguda em ratos. Novos estudos são necessários para avaliar a hepatoxicidade crônica de Equisetum arvense L. em ratos.
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Assessing the antimicrobial activities of Ocins
Directory of Open Access Journals (Sweden)
Shilja eChoyam
2015-09-01
Full Text Available The generation of a zone of inhibition on a solid substrate indicates the bioactivity of antimicrobial peptides such as bacteriocin and enterocin. The indicator strain plays a significant role in bacteriocin assays. Other characteristics of bacteriocins, such as their dispersal ability and the different zymogram components, also affect bacteriocin assays. However, universal well diffusion assays for antimicrobials, irrespective of their ability to diffuse (bacteriocin, enterocin, do not exist. The ability of different zymography components to generate non-specific activities have rarely been explored in the literature. The purpose of the present work was to evaluate the impact of two major factors (diffusion and no diffusion in a solid substrate bioassay, and to document the adverse effects of sodium dodecyl sulfate in zymograms used to estimate the approximate molecular weight of bacteriocins.
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Antiviral activity of Quercus persica L.: High efficacy and low toxicity
Directory of Open Access Journals (Sweden)
Ali Karimi
2013-01-01
Full Text Available Background: Drug-resistant strain of Herpes simplex virus type 1 (HSV-I has increased the interest in the use of natural substances. Aims: This study was aimed to determine minimum inhibitory concentration of hydroalchoholic extract of a traditionally used herbal plant, Quercus persica L., on HSV-1 replication on baby hamster kidney (BHK cells. Setting: The study was conducted in Shahrekord University of Medical Sciences, Iran. Design: This was an experimental study. Materials and Methods: BHK cells were grown in monolayer culture with Dulbecco′s modified Eagle′s medium (DMEM supplemented with 5% fetal calf serum and plated onto 48-well culture plates. Fifty percent cytotoxic concentration (CC50% of Q. persica L. on BHK cells was determined. Subsequently, 50% inhibitory concentration (IC50% of the extract on replication of HSV-1 both in interacellular and exteracellular cases was assessed. Statistical Analysis: Statistic Probit model was used for statistical analysis. The dose-dependent effect of antiviral activity of the extracts was determined by linear regression. Results: Q. persica L. had no cytotoxic effect on this cell line. There was significant relationship between the concentration of the extract and cell death (P<0.01. IC50s of Q. persica L. on HSV-1, before and after attachment to BHK cells were 1.02 and 0.257 μg/mL, respectively. There was significant relationship between the concentration of this extract and inhibition of cytopathic effect (CPE (P<0.05. Antioxidant capacity of the extract was 67.5%. Conclusions: The hydroalchoholic extract of Q. persica L. is potentially an appropriate and promising anti herpetic herbal medicine.
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Results For The Third Quarter Calendar Year 2016 Tank 50H Salt Solution Sample
Energy Technology Data Exchange (ETDEWEB)
Crawford, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2016-10-13
In this memorandum, the chemical and radionuclide contaminant results from the Third Quarter Calendar Year 2016 (CY16) sample of Tank 50H salt solution are presented in tabulated form. The Third Quarter CY16 Tank 50H samples (a 200 mL sample obtained 6” below the surface (HTF-5-16-63) and a 1 L sample obtained 66” from the tank bottom (HTF-50-16-64)) were obtained on July 14, 2016 and received at Savannah River National Laboratory (SRNL) on the same day. Prior to obtaining the samples from Tank 50H, a single pump was run at least 4.4 hours, and the samples were pulled immediately after pump shut down. The information from this characterization will be used by Defense Waste Processing Facility (DWPF) & Saltstone Facility Engineering for the transfer of aqueous waste from Tank 50H to the Saltstone Production Facility, where the waste will be treated and disposed of in the Saltstone Disposal Facility. This memorandum compares results, where applicable, to Saltstone Waste Acceptance Criteria (WAC) limits and targets. Data pertaining to the regulatory limits for Resource Conservation and Recovery Act (RCRA) metals will be documented at a later time per the Task Technical and Quality Assurance Plan (TTQAP) for the Tank 50H saltstone task. The chemical and radionuclide contaminant results from the characterization of the Third Quarter CY16 sampling of Tank 50H were requested by Savannah River Remediation (SRR) personnel and details of the testing are presented in the SRNL TTQAP.
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Energy Technology Data Exchange (ETDEWEB)
Grall, M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires
1964-12-01
This work is concerned with the study of acid-base reactions and of complex formation in ethanolamine and its mixtures with water. The ionic product of the solvent has been determined by an electro-chemical study of the H{sup +}/H{sub 2} system. The reduction curves for ethanolamine-water mixtures, for different acidities, have made it possible to follow the variations in the size of the pH domain as a function of the composition of the solvent. The form of this variation has been explained on the basis of the dielectric constant and the solvation of the proton by the ethanolamine. In the second part, the electrochemical systems of mercury have been studied by anodic polarography. In order to establish a parallel between the acid-base reactions and complex formation reactions, we have studied the stability of Hg (CN){sub 2} in water-ethanolamine mixtures. It has been possible to deduce the law for the variation of pK{sub c} with solvent composition. The representative graph of this function passes through a minimum for a proportion of about 50 per cent of ethanolamine as in the case of acids. This variation has been explained by the predominating influence of {epsilon} for ethanolamine propositions of over 50 per cent and by that of the solvation of Hg{sup 2+} for proportions of under 50 per cent. (author) [French] Ce travail porte sur l'etude des reactions acides-bases et de formation de complexes dans l'ethanolamine et ses melanges avec l'eau. Le produit ionique du solvant a pu etre determine par l'etude electro-chimique du systeme H{sup +}/H{sub 2}. Les courbes de reduction des melanges ethanolamine-eau, pour des acidites variables, ont permis de suivre les variations de l'etendue du domaine de pH, en fonction de la composition du solvant. L'allure de cette variation a ete expliquee en faisant intervenir la constante dielectrique et la solvatation du proton par l'ethanolamine. Dans une deuxieme partie, les systemes electrochimiques du mercure ont ete etudies par
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International Nuclear Information System (INIS)
Shariff, Fairolniza Mohd; Rahman, Raja Noor Zaliha Raja Abd.; Ali, Mohd Shukuri Mohamad; Chor, Adam Leow Thean; Basri, Mahiran; Salleh, Abu Bakar
2010-01-01
Thermostable recombinant L2 lipase from thermophilic Bacillus sp. L2 has been crystallized by using counter-diffusion method and diffracted to 2.7 Å resolution. The crystal belongs to the primitive orthorhombic space group P2 1 2 1 2 1 with unit-cell parameters a = 87.44, b = 94.90, c = 126.46 Å. Purified thermostable recombinant L2 lipase from Bacillus sp. L2 was crystallized by the counter-diffusion method using 20% PEG 6000, 50 mM MES pH 6.5 and 50 mM NaCl as precipitant. X-ray diffraction data were collected to 2.7 Å resolution using an in-house Bruker X8 PROTEUM single-crystal diffractometer system. The crystal belonged to the primitive orthorhombic space group P2 1 2 1 2 1 , with unit-cell parameters a = 87.44, b = 94.90, c = 126.46 Å. The asymmetric unit contained one single molecule of protein, with a Matthews coefficient (V M ) of 2.85 Å 3 Da −1 and a solvent content of 57%
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Starus, Anna; Nocek, Boguslaw; Bennett, Brian; Larrabee, James A; Shaw, Daniel L; Sae-Lee, Wisath; Russo, Marie T; Gillner, Danuta M; Makowska-Grzyska, Magdalena; Joachimiak, Andrzej; Holz, Richard C
2015-08-11
Binding of the competitive inhibitor L-captopril to the dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase from Neisseria meningitidis (NmDapE) was examined by kinetic, spectroscopic, and crystallographic methods. L-Captopril, an angiotensin-converting enzyme (ACE) inhibitor, was previously shown to be a potent inhibitor of the DapE from Haemophilus influenzae (HiDapE) with an IC50 of 3.3 μM and a measured Ki of 1.8 μM and displayed a dose-responsive antibiotic activity toward Escherichia coli. L-Captopril is also a competitive inhibitor of NmDapE with a Ki of 2.8 μM. To examine the nature of the interaction of L-captopril with the dinuclear active site of DapE, we have obtained electron paramagnetic resonance (EPR) and magnetic circular dichroism (MCD) data for the enzymatically hyperactive Co(II)-substituted forms of both HiDapE and NmDapE. EPR and MCD data indicate that the two Co(II) ions in DapE are antiferromagnetically coupled, yielding an S = 0 ground state, and suggest a thiolate bridge between the two metal ions. Verification of a thiolate-bridged dinuclear complex was obtained by determining the three-dimensional X-ray crystal structure of NmDapE in complex with L-captopril at 1.8 Å resolution. Combination of these data provides new insights into binding of L-captopril to the active site of DapE enzymes as well as important inhibitor-active site residue interaction's. Such information is critical for the design of new, potent inhibitors of DapE enzymes.
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Jiménez, Juan J; Diep, Dzung B; Borrero, Juan; Gútiez, Loreto; Arbulu, Sara; Nes, Ingolf F; Herranz, Carmen; Cintas, Luis M; Hernández, Pablo E
2015-10-15
Bacteriocins produced by lactic acid bacteria (LAB) attract considerable interest as natural and nontoxic food preservatives and as therapeutics whereas the bacteriocin-producing LAB are considered potential probiotics for food, human and veterinary applications, and in the animal production field. Within LAB the lactobacilli are increasingly used as starter cultures for food preservation and as probiotics. The lactobacilli are also natural inhabitants of the gastrointestinal (GI) tract and attractive vectors for delivery of therapeutic peptides and proteins, and for production of bioactive peptides. Research efforts for production of bacteriocins in heterologous hosts should be performed if the use of bacteriocins and the LAB bacteriocin-producers is ever to meet the high expectations deposited in these antimicrobial peptides. The recombinant production and functional expression of bacteriocins by lactobacilli would have an additive effect on their probiotic functionality. The heterologous production of the bacteriocin enterocin A (EntA) was evaluated in different Lactobacillus spp. after fusion of the versatile Sec-dependent signal peptide (SP usp45 ) to mature EntA plus the EntA immunity gene (entA + entiA) (fragment UAI), and their cloning into plasmid vectors that permitted their inducible (pSIP409 and pSIP411) or constitutive (pMG36c) production. The amount, antimicrobial activity (AA) and specific antimicrobial activity (SAA) of the EntA produced by Lactobacillus sakei Lb790, Lb. plantarum NC8 and Lb. casei CECT475 transformed with the recombinant plasmids pSIP409UAI, pSIP411UAI and pMGUAI varied depending of the expression vector and the host strain. The Lb. casei CECT475 recombinant strains produced the largest amounts of EntA, with the highest AA and SAA. Supernatants from Lb. casei CECT (pSIP411UAI) showed a 4.9-fold higher production of EntA with a 22.8-fold higher AA and 4.7-fold higher SAA than those from Enterococcus faecium T136, the natural
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Natural widths and Coster-Kronig transitions of L X-ray spectra in elements between Pd and Sb
International Nuclear Information System (INIS)
Sakakura, Shusuke; Oohashi, Hirofumi; Ito, Yoshiaki; Tochio, Tatsunori; Vlaicu, Aurel M.; Yoshikawa, Hideki; Ikenaga, Eiji; Kobayashi, Keisuke
2006-01-01
The Lα and Lβ X-ray emission spectra in the elements between Pd (Z=46) and Sb (Z=51) were measured using a high-resolution double-crystal vacuum spectrometer. The relative intensities of satellite structures, which originate in L 1 L 3 M 4,5 Coster-Kronig transitions, were estimated to that of each diagram line, and compared with calculated values. According to the work of Chen et al. [1977a. Theoretical L-shell Coster-Kronig energies 11≤Z≤103. At. Data Nucl. Data Tables 19, 97-151], Salgueiro et al. [1987. J. Phys. (Paris) 48 Colloq. C9, 609] and Vlaicu et al. [1998. Investigation of the 74W L emission spectra and satellites. Phys. Rev. A 58, 3544] L 1 L 3 M 4 Coster-Kronig transition is forbidden for 50≤Z≤77, and L 1 L 3 M 5 Coster-Kronig transition is forbidden for 50≤Z≤73. The results suggest that L 1 L 3 M 4,5 Coster-Kronig transitions may be allowed even for Sn (Z=50) and Sb (Z=51)
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Performing Leadership: Observations from the World of Music
Ralph Bathurst; Donna Ladkin
2012-01-01
This paper explores leadership as an emergent social process. We begin by discussing and contesting the tradition privileging linear management processes, and offer as a counterpoint accounts of distributed leadership out of which our focus on leadership as a plural process grows. Our concept of leadership as a plural process is enriched by an inquiry into musical ensembles with formal leaders as well as those which are leaderless that find ways of moving collectively towards shared goals. Th...
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Dynamical Consensus Algorithm for Second-Order Multi-Agent Systems Subjected to Communication Delay
International Nuclear Information System (INIS)
Liu Chenglin; Liu Fei
2013-01-01
To solve the dynamical consensus problem of second-order multi-agent systems with communication delay, delay-dependent compensations are added into the normal asynchronously-coupled consensus algorithm so as to make the agents achieve a dynamical consensus. Based on frequency-domain analysis, sufficient conditions are gained for second-order multi-agent systems with communication delay under leaderless and leader-following consensus algorithms respectively. Simulation illustrates the correctness of the results. (interdisciplinary physics and related areas of science and technology)
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Tsurugi, K; Collatz, E; Wool, E G; Lin, A
1976-12-25
The proteins of the large subunit of rat liver ribosomes were separated into seven groups by stepwise elution from carboxymethylcellulose with LiCl at pH 6.5. Seventeen proteins (L4, L5, L7, L9, L11, L12, L13, L21, L22, L23, L26, L27, L30, L33, L35', L37, and L39) were isolated from three of the groups (B60, D60, G60) by ion exchange chromatography on carboxymethylcellulose and by filtration through Sephadex. The amount of protein obtained varied from 0.5 to 15 mg. Eight of the proteins (L9, L11, L13, L21, L22, L35', L37 and L39) had no detectable contamination; the impurities in the others were no greater than 9%. The molecular weight of the proteins was estimated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate; the amino acid composition was determined.
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Efeito leishmanicida in vitro do látex de Croton lechleri (Euphorbiaceae
Directory of Open Access Journals (Sweden)
Ana Paula Azevedo Santos
2016-07-01
Full Text Available A Leishmaniose Tegumentar Americana é uma infecção causada por uma variedade de espécies de Leishmania, é transmitida ao homem por flebotomíneos. Os antimoniais pentavalentes são utilizados na quimioterapia dessa doença; no entanto, esses fármacos provocam uma série de efeitos colaterais, além de apresentar altos índices de toxicidade. Na busca por novos agentes leishmanicidas, avaliamos in vitro o extrato do látex de Croton lechleri (Sangue de dragão frente a formas promastigotas de Leishmania amazonensis e Leishmania guyanensis. O extrato foi obtido através da desidratação do látex de C. lechleri e diluído em solução 10% de etanol em salina tamponada com fosfato. As promastigotas de Leishmania foram cultivadas juntamente com o extrato nas concentrações de 6,25; 12,5 e 25μg/ mL por 72 horas. O extrato apresentou eficácia em todas as concentrações testadas apresentando um IC 50 (concentração inibitória de 5,04μg/mL para L. amazonensis e IC 50 de 9,05μg/mL para L. guyanensis. Foi realizada a avaliação citotóxica em células J774 nas mesmas concentrações usadas no ensaio leishmanicida, porém a concentração de 25μg/mL apresentou índice de toxicidade de aproximadamente 50% para a célula hospedeira. Os testes realizados mostraram-sepromissores, pois o extrato testado também foi capaz de inibir o crescimento de promastigotas de L. amazonensis após ensaio de infecção com células J774.Palavras-chave: Croton lechleri. Atividade leishmanicida. Atividade citotóxica. ABSTRACTIn vitro leishmanicidal effect of Croton lechleri latexCutaneous Leishmaniasis is an infection caused by a several species of Leishmania, is transmitted to humans by phlebotomine sandflies. Pentavalent antimonial compounds are used in the chemotherapy of this disease; however, these drugs cause several collateral effects, besides presenting high levels of toxicity. The search for new antiLeishmanial agents, we assessed in vitro the
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Directory of Open Access Journals (Sweden)
Azat Gabdulkhakov
2017-02-01
Full Text Available The crystal structure of the 92-nucleotide L1-specific fragment of 23S rRNA from Haloarcula marismortui (Hma has been determined at 3.3 Å resolution. Similar to the corresponding bacterial rRNA fragments, this structure contains joined helix 76-77 topped by an approximately globular structure formed by the residual part of the L1 stalk rRNA. The position of HmaL1 relative to the rRNA was found by its docking to the rRNA fragment using the L1-rRNA complex from Thermus thermophilus as a guide model. In spite of the anomalous negative charge of the halophilic archaeal protein, the conformation of the HmaL1-rRNA interface appeared to be very close to that observed in all known L1-rRNA complexes. The designed structure of the L1 stalk was incorporated into the H. marismortui 50S ribosomal subunit. Comparison of relative positions of L1 stalks in 50S subunits from H. marismortui and T. thermophilus made it possible to reveal the site of inflection of rRNA during the ribosome function.
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Two novel bioactive glucosinolates from Broccoli (Brassica oleracea L. var. italica) florets.
Survay, Nazneen Shaik; Kumar, Brajesh; Jang, Mi; Yoon, Do-Young; Jung, Yi-Sook; Yang, Deok-Chun; Park, Se Won
2012-09-01
Two novel glucosinolates along with one known glucosinolate were isolated from Broccoli (Brassica oleracea L. var. italica) florets. Their structures were established mainly by 1D ((1)H and (13)C NMR), 2D NMR ((1)H-(1)H COSY, DEPT 135°, HSQC and HMBC), and Tandem MS-MS spectrometric data as 2-mercaptomethyl sulfinyl glucosinolate [(Z)-4-(methylsulfinyl)-N-(sulfooxy)-2-((2'S,3'R,4'S,5'S,6'R)-3',4',5'-trihydroxy-6'(hydroxylmethyl)-2'-mercapto tetrahydro-2H-pyran-2-yl) butane amide] 1, (Z)-1-((2S,5S)-5-hydroxytetra-hydro-2H-pyran-2-ylthio)-2-(1H-indol-3-yl) ethylidene amino sulfate 2 and a known cinnamoyl [6'-O-trans-(4″-hydroxy cinnamoyl)4-(methylsulphinyl)butyl glucosinolate] 3. Compound 1 exhibited scavenging activity against DPPH with an inhibitory concentration IC(50) of 20 mM, whereas compound 3 was a weak antioxidant when compared to the standard quercetin (5 mM) as a positive control. Both the compounds showed a significant and similar antimicrobial activity against Staphylococcus aureus with an IC(50) of <625 μg/mL when compared to antibiotic duricef. Against Salmonella typhimurium the IC(50) of 1 and 3 was determined as <625 μg/mL and <1250 μg/mL, respectively, when compared to ampicillin (IC(50) ≤ 39 μg/mL) as a positive control. Copyright © 2012 Elsevier Ltd. All rights reserved.
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International Nuclear Information System (INIS)
1984-10-01
This report supplements the Safety Evaluation Report (NUREG-0831) issued in September 1981 by the Office of Nuclear Reactor Regulation of the US Nuclear Regulatory Commission with respect to the application filed by Mississippi Power and Light (MP and L) Company, Middle South Energy, Inc., and South Mississippi Electric Power Association as applicants and owners, for licenses to operate the Grand Gulf Nuclear Station, Units 1 and 2 (Docket Nos. 50-416 and 50-417, respectively). The facility is located on the east bank of the Mississippi River near Port Gibson in Claiborne County, Mississippi. This supplement provides information on the NRC staff's evaluation of requests for exemptions to NRC regulations pursuant to the Commission's direction in CLI-84-19, dated October 25, 1984
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Results for the first quarter calendar year 2017 tank 50H salt solution sample
Energy Technology Data Exchange (ETDEWEB)
Crawford, C. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2017-04-12
In this memorandum, the chemical and radionuclide contaminant results from the First Quarter Calendar Year 2017 (CY17) sample of Tank 50H salt solution are presented in tabulated form. The First Quarter CY17 Tank 50H samples [a 200 mL sample obtained 6” below the surface (HTF-50-17-7) and a 1 L sample obtained 66” from the tank bottom (HTF-50-17-8)] were obtained on January 15, 2017 and received at Savannah River National Laboratory (SRNL) on January 16, 2017. Prior to obtaining the samples from Tank 50H, a single pump was run at least 4.4 hours and the samples were pulled immediately after pump shut down. All volatile organic analysis (VOA) and semi-volatile organic analysis (SVOA) were performed on the surface sample and all other analyses were performed on the variable depth sample. The information from this characterization will be used by Savannah River Remediation (SRR) for the transfer of aqueous waste from Tank 50H to the Saltstone Production Facility, where the waste will be treated and disposed of in the Saltstone Disposal Facility. This memorandum compares results, where applicable, to Saltstone Waste Acceptance Criteria (WAC) limits and targets. The chemical and radionuclide contaminant results from the characterization of the First Quarter CY17 sampling of Tank 50H were requested by SRR personnel and details of the testing are presented in the SRNL Task Technical and Quality Assurance Plan (TTQAP). This memorandum is part of Deliverable 2 from SRR request. Data pertaining to the regulatory limits for Resource Conservation and Recovery Act (RCRA) metals will be documented at a later time per the TTQAP for the Tank 50H saltstone task.
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Directory of Open Access Journals (Sweden)
Ahmet Ozkaya
2013-01-01
Full Text Available The levels of fat-soluble vitamin, trace element and fatty acid of Vitex agnus-castus L., Juniperus oxycedrus L., and Papaver somniferum L. seeds in Turkey were determined by using HPLC, ICP-OES, and GC, respectively. In the Vitex agnus-castus L., Juniperus oxycedrus L., and Papaver somniferum L. seeds, linoleic acid (18 : 2 was determined with the highest level rates (%54.11, %28.03, and %72.14, resp.. In the Vitex agnus-castus L. seeds, R-tocopherol, α-tocopherol, and K1 levels were determined as 9.70 μg/g, 18.20 μg/g, and 24.79 μg/g, respectively; In the Juniperus oxycedrus L. seeds, R-tocopherol, α-tocopherol, and K1 were determined as 18.50 μg/g, 0.84 μg/g, and 5.00 μg/g, respectively, and in the Papaver somniferum L. seeds, R-tocopherol, α-tocopherol, K1, and D2 levels were determined as 43.25 μg/g, 122.05 μg/g, 12.01 μg/g, and 0.62 μg/g, respectively. In the Vitex agnus-castus L., Juniperus oxycedrus L., and Papaver somniferum L. seeds, nickel (Ni, zinc (Zn, and iron (Fe were determined with the trace element level rates (4.42 mg/kg, 10.43 mg/kg, 3.71 mg/kg for Ni, 7.00 mg/kg, 7.70 mg/kg, and 24 mg/kg for Zn and 93.73 mg/kg, 187.95 mg/kg, and 149.64 mg/kg for Fe, resp.. These parameters in seeds are very important for human life.
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Chayapan, P; Kruatrachue, M; Meetam, M; Pokethitiyook, P
2015-09-01
Cadmium and zinc phytoremediation potential of wetland plants, Colocasia esculenta, Cyperus malaccensis, and Typha angustifolia, was investigated. Plants were grown for 15 days in nutrient solutions containing various concentrations of Cd (0, 5, 10, 20, 50 mg l(-1)) and Zn (0, 10, 20, 50, 100 mg l(-1)). T angustifolia was tolerant to both metals as indicated by high RGR when grown in 50 mg I(-1) Cd and 100 mg I(-1) Zn solutions. All these plants accumulated more metals in their underground parts and > 100 mg kg(-1) in their aboveground with TF values 10,000 mg kg(-1) in its aboveground parts with TF > 1. T angustifolia exhibited highest biomass production and highest Cd and Zn uptake, confirming that this plant is a suitable candidate for treating of Cd contaminated soil/sediments.
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Directory of Open Access Journals (Sweden)
Malek Besbes Hlila
2016-08-01
Full Text Available Objective: To examine the potential antioxidant and anti-α-glucosidase inhibitory activities of Tunisian Euphorbia paralias L. leaves and stems extracts and their composition of total polyphenol and flavonoids. Methods: The different samples were tested for their antiradical activities by using 2, 2’- azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS and 1,1-diphenyl-2-picrylhydrazyl (DPPH assays. In α-glucosidase activity, α-glucosidase (0.3 IU/mL and substrate, 2500 µmol/ L p-nitrophenyl α-D-glucopyranoside were used; absorbance was registered at 405 nm. Results: The leaves acetonic extract exhibited the strongest α-glucosidase inhibition [IC50 = (0.0035 ± 0.001 µg/mL], which was 20-fold more active than the standard product (acarbose [IC50 = (0.07 ± 0.01 µg/mL]. Acetonic extract of the leaves exhibited the highest quantity of total phenolic [(95.54 ± 0.04 µg gallic acid equivalent/mg] and flavonoid [(55.16 ± 0.25 µg quercetin equivalent/mg]. The obtained findings presented also that this extract was detected with best antioxidant capacity [IC50 = (0.015 ± 0.01 µg/mL] against DPPH and a value of IC50 equal to (0.02 ± 0.01 µg/mL against ABTS. Positive relationship between polyphenolic content of the tested Euphorbia paralias L. leaves and stems extracts and its antioxidant activity (DPPH and ABTS was detected. Elevated positive linear correlation was got between ABTS and total phenolic (R2 = 0.751. Conclusions: The findings clearly demonstrate that the use of a polar solvent enables extraction of significant quantities of phenol compounds and flavonoids.
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Oestrogen directly inhibits the cardiovascular L-type Ca2+ channel Cav1.2
International Nuclear Information System (INIS)
Ullrich, Nina D.; Koschak, Alexandra; MacLeod, Kenneth T.
2007-01-01
Oestrogen can modify the contractile function of vascular smooth muscle and cardiomyocytes. The negative inotropic actions of oestrogen on the heart and coronary vasculature appear to be mediated by L-type Ca 2+ channel (Ca v 1.2) inhibition, but the underlying mechanisms remain elusive. We tested the hypothesis that oestrogen directly inhibits the cardiovascular L-type Ca 2+ current, I CaL . The effect of oestrogen on I CaL was measured in Ca v 1.2-transfected HEK-293 cells using the whole-cell patch-clamp technique. The current revealed typical activation and inactivation profiles of nifedipine- and cadmium-sensitive I CaL . Oestrogen (50 μM) rapidly reduced I CaL by 50% and shifted voltage-dependent activation and availability to more negative potentials. Furthermore, oestrogen blocked the Ca 2+ channel in a rate-dependent way, exhibiting higher efficiency of block at higher stimulation frequencies. Our data suggest that oestrogen inhibits I CaL through direct interaction of the steroid with the channel protein
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50th IMO - 50 Years of International Mathematical Olympiads
Gronau, Hans-Dietrich; Schleicher, Dierk
2011-01-01
In July 2009 Germany hosted the 50th International Mathematical Olympiad (IMO). For the very first time the number of participating countries exceeded 100, with 104 countries from all continents. Celebrating the 50th anniversary of the IMO provides an ideal opportunity to look back over the past five decades and to review its development to become a worldwide event. This book is a report about the 50th IMO as well as the IMO history. A lot of data about all the 50 IMOs are included. We list the most successful contestants, the results of the 50 Olympiads and the 112 countries that have ever ta
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Directory of Open Access Journals (Sweden)
Meryem El Jemli
2016-01-01
Full Text Available Objective. The aim of this work is to study and compare the antioxidant properties and phenolic contents of aqueous leaf extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus Phoenicea, and Tetraclinis articulata from Morocco. Methods. Antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH free radical-scavenging ability, Trolox equivalent antioxidant capacity (TEAC, and ferric reducing antioxidant power (FRAP assays. Also the total phenolic and flavonoids contents of the extracts were determined spectrophotometrically. Results. All the extracts showed interesting antioxidant activities compared to the standard antioxidants (butylated hydroxytoluene (BHT, quercetin, and Trolox. The aqueous extract of Juniperus oxycedrus showed the highest antioxidant activity as measured by DPPH, TEAC, and FRAP assays with IC50 values of 17.91±0.37 μg/mL, 19.80±0.55 μg/mL, and 24.23±0.07 μg/mL, respectively. The strong correlation observed between antioxidant capacities and their total phenolic contents indicated that phenolic compounds were a major contributor to antioxidant properties of these plants extracts. Conclusion. These results suggest that the aqueous extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus phoenicea, and Tetraclinis articulata can constitute a promising new source of natural compounds with antioxidants ability.
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El Jemli, Meryem; Kamal, Rabie; Marmouzi, Ilias; Zerrouki, Asmae; Cherrah, Yahia; Alaoui, Katim
2016-01-01
Objective. The aim of this work is to study and compare the antioxidant properties and phenolic contents of aqueous leaf extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus Phoenicea, and Tetraclinis articulata from Morocco. Methods. Antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging ability, Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP) assays. Also the total phenolic and flavonoids contents of the extracts were determined spectrophotometrically. Results. All the extracts showed interesting antioxidant activities compared to the standard antioxidants (butylated hydroxytoluene (BHT), quercetin, and Trolox). The aqueous extract of Juniperus oxycedrus showed the highest antioxidant activity as measured by DPPH, TEAC, and FRAP assays with IC50 values of 17.91 ± 0.37 μg/mL, 19.80 ± 0.55 μg/mL, and 24.23 ± 0.07 μg/mL, respectively. The strong correlation observed between antioxidant capacities and their total phenolic contents indicated that phenolic compounds were a major contributor to antioxidant properties of these plants extracts. Conclusion. These results suggest that the aqueous extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus phoenicea, and Tetraclinis articulata can constitute a promising new source of natural compounds with antioxidants ability.
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Institute of Scientific and Technical Information of China (English)
Abbas Khani; Monireh Heydarian
2014-01-01
Objective:To test fumigant and repellent properties of sesquiterpene-rich essential oil from Teucrium polium subsp.capitatum(L.).Methods:The fumigant toxicity test was performed at(27±1)℃,(65±5)% relative humidity, and under darkness condition and24 h exposure time.The chemical composition of the isolated oils was examined by gas chromatography-mass spectrometry.Results:The major compounds wereα-cadinol(46.2%), caryophyllene oxide(25.9%), α muurolol epi(8.1%), cadalene(3.7%) and longiverbenone(2.9%).In all cases, considerable differences in mortality of insect to essential oil vapor were observed in different concentrations and exposure times.Callosobruchus maculatus(C. maculates)(LC50=148.9 μL/L air) was more susceptible to the tested plant product thanTeucrium castaneum(T. castaneum) (LC50=360.2 μL/L air) based onLC50 values.In the present investigation, the concentration of3 μL /mL acetone showed60% and52% repellency againstT. casteneumandC. maculatus adults, respectively.Conclusions:The results suggests that sesquiterpene-rich essential oils from the tested plant could be used as a potential control agent for stored-product insects.
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Hemoglobin P50 During a Simulated Ascent of Mt. Everest, Operation Everest II
2007-01-01
standard HbP50 would in- crease with increasing altitude [on the basis of increased levels of 2,3- diphosphoglycerate , which rose from 1.7 0.3 mmol/L...the re- sult of an increase in 2,3- diphosphoglycerate [2,3-DPG] levels induced by hypoxia (Chanutin and Curnish, 1967; Lenfant et al., 1969; Boushel... diphosphoglycerate of rats and guinea pigs. Respir. Physiol. 11:135. Bencowitz H.Z., Wagner P.D., and West J.B. (1982). Effect of change on P50 on
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Shin, Keon Sung; Zhao, Ting Ting; Park, Keun Hong; Park, Hyun Jin; Hwang, Bang Yeon; Lee, Chong Kil; Lee, Myung Koo
2015-04-21
Gypenosides (GPS) and ethanol extract of Gynostemma pentaphyllum (GP-EX) show anxiolytic effects on affective disorders in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned mouse model of Parkinson's disease (PD). Long-term administration of L-3,4-dihydroxyphenylalanine (L-DOPA) leads to the development of severe motor side effects such as L-DOPA-induced-dyskinesia (LID) in PD. The present study investigated the effects of GPS and GP-EX on LID in a 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD. Daily administration of L-DOPA (25 mg/kg) in the 6-OHDA-lesioned rat model of PD for 22 days induced expression of LID, which was determined by the body and locomotive AIMs scores and contralateral rotational behaviors. However, co-treatments of GPS (25 and 50 mg/kg) or GP-EX (50 mg/kg) with L-DOPA significantly attenuated the development of LID without compromising the anti-parkinsonian effects of L-DOPA. In addition, the increases in ∆FosB expression and ERK1/2 phosphorylation in 6-OHDA-lesioned rats induced by L-DOPA administration were significantly reduced by co-treatment with GPS (25 and 50 mg/kg) or GP-EX (50 mg/kg). These results suggest that GPS (25 and 50 mg/kg) and GP-EX (50 mg/kg) effectively attenuate the development of LID by modulating the biomarker activities of ∆FosB expression and ERK1/2 phosphorylation in the 6-OHDA-lesioned rat model of PD. GPS and GP-EX will be useful adjuvant therapeutics for LID in PD.
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Directory of Open Access Journals (Sweden)
Ikram-ul Haq
2006-03-01
Full Text Available Aspergillus oryzae mutant strain UV-7 was further improved for the production of L-DOPA from L-tyrosine using chemical mutation. Different putative mutant strains of organism were tested for the production of L-DOPA in submerged fermentation. Among these putative mutant strains, mutant designated SI-12 gave maximum production of L-DOPA (300 mg L-DOPA.g-1 cells. The production of L-DOPA from different carbon source solutions (So= 30 g.l-1 by mutant culture was investigated at different nitrogen sources, initial pH and temperature values. At optimum pH (pHo= 5.0, and temperature (t=30ºC, 100% sugars were utilized for production and cell mass formation, corresponding to final L-DOPA product yield of 150 mg.g-1 substrate utilized, and maximum volumetric and specific productivities of 125 mg.l-1.h-1, and 150 mg.g-1 cells. h-1, respectively. There was up to 3-fold enhancement in product formation rate. This enhancement is the highest reported in literature. To explain the kinetic mechanism of L-DOPA formation and thermal inactivation of tyrosinase, the thermodynamic parameters were determined with the application of Arrhenius model: activation enthalpy and entropy for product formation, in case of mutant derivative, were 40 k j/mol and 0.076 k j/mol. K for L-DOPA production and 116 k j/mol and 0.590 k j/mol. K for thermal inactivation, respectively. The respective values for product formation were lower while those for product deactivation were higher than the respective values for the parental culture. Therefore, the mutant strain was thermodynamically more resistant to thermal denaturation.A produção de L-DOPA a partir de tirosina pela cepa mutante de Aspergillus orizae UV-7 foi melhorada através de mutação química. Diferentes cepas foram testadas quanto a produção de L-DOPA por fermentação submersa, observando-se que a cepa denominada SI-12 foi a melhor produtora (300 mg de L-DOPA por g de células. A produção de L-DOPA pela cepa
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Ethnobotanical, phytochemical and toxicological studies of Xanthium strumarium L.
Islam, Mohammad Rashedul; Uddin, Mohammad Zashim; Rahman, Mohammad Sharifur; Tutul, Ershad; Rahman, Mohammed Zakiur; Hassan, Md Abul; Faiz, M A; Hossain, Moazzem; Hussain, Maleeha; Rashid, Mohammad Abdur
2009-12-01
The present study describes the ethnobotanical, phytochemical, and toxicological evaluations of Xanthium strumarium L. growing in Bangladesh. In toxicity evaluation on rats, the methanol extract of seedlings showed mortality, while both seedling and mature plant extracts raised the serum alanine transaminase and aspartate transaminase values and produced significant abnormalities in the histopathology of liver and kidney of rats. On the other hand, the aqueous soluble fraction of methanol extract of mature plant (LC50 = 0.352 microg/mL) and methanol crude extract of seedlings (LC50 = 0.656 microg/mL) demonstrated significant toxicity in the brine shrimp lethality bioassay. A total of four compounds were purified and characterized as stigmasterol (1), 11-hydroxy-11-carboxy-4-oxo-1(5),2(Z)-xanthadien-12,8-olide (2), daucosterol (3) and lasidiol-10-anisate (4). The present study suggests that X. strumarium is toxic to animal.
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Peripheral Blood and Bone Marrow Changes in Chronic Renal Failure (Investigation of 50 Cases
Directory of Open Access Journals (Sweden)
Seyed Nasroiah Sayar
1973-07-01
Full Text Available Anemia and morphological features of the hemopoietic system in 50 Iranian patients suffering from chronic uremia was investigated. The results were compared with the results observed by others; our findings in most instances are nearly in accordance but with the following differences: Whenblood urea was above 401 mg 'X, (BUN 187 there was a slight fall in hemoglobin concentration; anemia was normocytic, rarely macrocytic, or microcytic, and hypochromic in 72 (~l~~; of our patients, 28 ~l,':l of them had concomitant iron deficiency anemia demonstrable by absence or reduction of stainable iron in their marrow.
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Lin, Yuan; Li, Yan; Zhu, Ningyu; Han, Yanxing; Jiang, Wei; Wang, Yanchang; Si, Shuyi; Jiang, Jiandong
2014-01-01
Capreomycin is a second-line drug for multiple-drug-resistant tuberculosis (TB). However, with increased use in clinics, the therapeutic efficiency of capreomycin is decreasing. To better understand TB resistance to capreomycin, we have done research to identify the molecular target of capreomycin. Mycobacterium tuberculosis ribosomal proteins L12 and L10 interact with each other and constitute the stalk of the 50S ribosomal subunit, which recruits initiation and elongation factors during translation. Hence, the L12-L10 interaction is considered to be essential for ribosomal function and protein synthesis. Here we provide evidence showing that capreomycin inhibits the L12-L10 interaction by using an established L12-L10 interaction assay. Overexpression of L12 and/or L10 in M. smegmatis, a species close to M. tuberculosis, increases the MIC of capreomycin. Moreover, both elongation factor G-dependent GTPase activity and ribosome-mediated protein synthesis are inhibited by capreomycin. When protein synthesis was blocked with thiostrepton, however, the bactericidal activity of capreomycin was restrained. All of these results suggest that capreomycin seems to inhibit TB by interrupting the L12-L10 interaction. This finding might provide novel clues for anti-TB drug discovery.
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Patel, Suman; Gaur, Rashmi; Verma, Priyanka; Bhakuni, Rajendra S; Mathur, Archana
2010-08-01
Artemisinin, an antimalarial compound, at 5 mg/40 ml, was transformed by cell suspension cultures of Catharanthus roseus (L.) G.Don and Lavandula officinalis L. into deoxyartemisinin with yields >78% (3.93 mg deoxyartemisinin from 5 mg artemisinin). Maximum conversion (78.6 and 78%) occurred after 6 and 7 days of adding artemisinin to 20 and 9 days old cultures of C. roseus and L. officinalis, respectively. The procedure was scaled up by and 500 mg artemisinin was transformed into 390 mg deoxyartemisinin. Addition of artemisinin at the beginning of the culture cycle resulted in >50% reduction in dry biomass production with no bioconversion. Conversion of artemisinin occurred intracellularly followed by leaching of the product into the medium.
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Directory of Open Access Journals (Sweden)
Gloria Yaluff
2015-08-01
Full Text Available La tripanosomiasis americana y la leishmaniosis son problemas de salud pública relevantes en Iberoamérica. Se evaluó la actividad antiparasitaria in vitro de extractos de cortezas y hojas de Erythrina crista-galli L., E. dominguezii Hassl y E. falcata Benth sobre formas tripomastigotas de Trypanosoma cruzi y promastigotas de Leishmania amazonensis, L. infantum L. braziliensis. El extracto de corteza de E. dominguezii Hassl presentó CI50 de 11,7 μg/ml y 14,9 μg/ml con dos cepas de T. cruzi, Ypsilon y Cl Brener. El extracto de hoja presentó CI50 mayor a 250 μg/ml. La corteza de E. falcata Benth tuvo CI50 de 11,29 μg/ml y 7,37 μg/ml con Ypsilon y Cl Brener y el extracto de hojas CI50 de 37,2 μg/ml y 25,68 μg/ml. El extracto de hojas de E. crista-galli L. presentó CI50 mayor a 250 μg/ml, y el de corteza CI50 11,2μg/ml y 7,1μg/ml con Ypsilon y Cl Brener. El extracto de corteza de E. dominguezii Hassl presentó CI50 de 3,22 μg/ml, 6,94 μg/ml y 1,9 μg/ml para L. amazonensis, L. infantum y L. braziliensis y en hojas la CI50 fue mayor a 100 μg/ml. La corteza de E. crista-galli L. tuvo CI50 de 2,1 μg/ml, 2,09 μg/ml y 1,6 μg/ml para las tres especies. El extracto de hoja tuvo una CI50 mayor a 100 μg/ml. El extracto de corteza de E. falcata Benth tuvo CI50 de 2,17 μg/ml, 2,09 μg/ml y 1,52 μg/ml con las tres especies de Leishmania y el de hoja CI50 de 14,9 μg/ml, 10,4 μg/ml y 11,6 μg/ml. Los extractos de corteza podrían ser una alternativa para el tratamiento de estas enfermedades parasitarias, previa confirmación con estudios in vivo y de toxicidad.
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Energy Technology Data Exchange (ETDEWEB)
Noel, P
2005-06-15
Although the oil price is still far from its historical maximum, the oil market is today in crisis. To explain this situation the author discusses the nature of the supply constraints. The reserves are today better known and so more plentiful than at a previous period of the oil history and the russian production since 2004 is stagnating. The main factor seems to be the OPEC policy and in particular the will of limiting the oil production to defend upper prices. (A.L.B.)
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Cirkovic, Ivana; Bozic, Dragana D; Draganic, Veselin; Lozo, Jelena; Beric, Tanja; Kojic, Milan; Arsic, Biljana; Garalejic, Eliana; Djukic, Slobodanka; Stankovic, Slavisa
2016-01-01
Coagulase negative staphylococci (CoNS) and Listeria monocytogenes have important roles in pathogenesis of various genital tract infections and fatal foetomaternal infections, respectively. The aim of our study was to investigate the inhibitory effects of two novel bacteriocins on biofilms of CoNS and L. monocytogenes genital isolates. The effects of licheniocin 50.2 from Bacillus licheniformis VPS50.2 and crude extract of bacteriocins produced by Lactococcus lactis subsp. lactis biovar. diacetylactis BGBU1-4 (BGBU1-4 crude extract) were evaluated on biofilm formation and formed biofilms of eight CoNS (four S. epidermidis, two S. hominis, one S. lugdunensis and one S. haemolyticus) and 12 L. monocytogenes genital isolates. Licheniocin 50.2 and BGBU1-4 crude extract inhibited the growth of both CoNS and L. monocytogenes isolates, with MIC values in the range between 200-400 AU/ml for licheniocin 50.2 and 400-3200 AU/ml for BGBU1-4 crude extract. Subinhibitory concentrations (1/2 × and 1/4 × MIC) of licheniocin 50.2 inhibited biofilm formation by all CoNS isolates (p < 0.05, respectively), while BGBU1-4 crude extract inhibited biofilm formation by all L. monocytogenes isolates (p < 0.01 and p < 0.05, respectively). Both bacteriocins in concentrations of 100 AU/mL and 200 AU/mL reduced the amount of 24 h old CoNS and L. monocytogenes biofilms (p < 0.05, p < 0.01, p < 0.001). This study suggests that novel bacteriocins have potential to be used for genital application, to prevent biofilm formation and/or to eradicate formed biofilms, and consequently reduce genital and neonatal infections by CoNS and L. monocytogenes.
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Directory of Open Access Journals (Sweden)
Amanda Venturini Arantes
2013-06-01
Full Text Available Objetivos: O presente estudo investigou a atividade antimicrobiana do extrato obtido das folhas de Jatropha curcas L., frente às bactérias Staphylococcus aureus e Escherichia coli isoladas de pacientes de um Hospital Escola do sul de Minas Gerais. Metodologia: Foi realizado o teste da Microdiluição em placas de 96 poços. Colocou-se 50µl de Ágar Mueller Hinton em todos os poços, seguidos de 50µl do extrato da planta em diferentes concentrações (25 a 200 mg/mL nas colunas apropriadas e em seguida, 10µl de cada cepa bacteriana na concentração de 0,5 de McFarland em solução salina estéril. Seguiu-se a incubação em estufa de 35ºC por 24h. Posteriormente, realizou-se a revelação pela adição de 20 µL de Cloreto de Trifenil Tetrezólico e análise dos resultados pela coloração. Em cada placa foi realizado um controle positivo e negativo. Resultados: Houve efeito inibitório do crescimento microbiano de S. aureus e E. coli perante extratos de Jatropha Curcas L. nas concentrações de 50mg a 200mg. Apenas na concentração de 25mg não houve efeito inibitório diante de E. coli e S. aureus. Conclusão: O extrato bruto de Jatropha curcas L. apresentou atividade inibitória do crescimento de colônias de Staphylococcus aureus e Escherichia coli isoladas de pacientes de um hospital escola do sul de Minas Gerais, nas concentrações 50, 75, 100, 125, 150, 175 e 200mg/ml. Objectives: This study investigated the antimicrobial activity of the extract obtained from the leaves of Jatropha curcas L., on the bacteria Staphylococcus aureus and Escherichia coli isolated from patients at a university hospital in southern Minas Gerais. Methodology: The microdilution test was made in plates of 96 wells. An amount of 50mL of Mueller Hinton agar was placed into each well, followed by 50mL of plant extract in different concentrations (25-200 mg / ml in the appropriate columns, and then 10ml of each bacterial strain at a concentration of 0.5 Mc
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Bacteriocinogenic potential and genotypic characterization of three ...
African Journals Online (AJOL)
Louiza
2015-08-06
Aug 6, 2015 ... Complete inactivation in bacteriocinogenic activity was observed after treatment with .... enterocins, with inhibitory activity against strains closely related to the ... buffered medium; ATCC, American Type Culture Collection; ND, not detected. Phenotypic ..... The thermal stability of bacteriocins produced by.
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Directory of Open Access Journals (Sweden)
Haixia Zhang
2018-01-01
Full Text Available Background. The changes in corneal biomechanical properties after LASIK remain an unknown but important topic for surgical design and prognostic evaluation. This study aims to observe the postoperative corneal biomechanical properties one month after LASIK with amount of corneal cutting (ACC greater than 50% of the central corneal thickness (CCT. Methods. FS-LASIK was performed in 10 left rabbit eyes with ACC being 60% (L60 and 65% (L65 of the CCT, while the right eyes (R were the control. After 4 weeks, rabbits were executed and corneal strip samples were prepared for uniaxial tensile tests. Results. At the same strain, the stresses of L65 and L60 were larger than those of R. The elastic moduli of L60 and L65 were larger than those of R when the stress was 0.02 MPa, while they began to be less than those of R when stress exceeds the low-stress region. After 10 s relaxation, the stress of specimens L65, L60, and R increased in turn. Conclusion. The elastic moduli of the cornea after FS-LASIK with ACC greater than 50% of the CCT do not become less under normal rabbit IOP. The limit stress grows with the rise of ACC when relaxation becomes stable.
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In vitro free radical scavenging activity of Ixora coccinea L
Directory of Open Access Journals (Sweden)
Moni Rani Saha
2008-06-01
Full Text Available Antioxidant activity of the methanol extract of Ixora coccinea L. was determined by DPPH free radical scavenging assay, reducing power and total antioxidant capacity using phosphomolybdenum method. Preliminary phytochemical screening revealed that the extract of the flower of I. coccinea possesses flavonoids, steroids and tannin materials. The extract showed significant activities in all antioxidant assays compared to the standard antioxidant in a dose dependent manner and remarkable activities to scavenge reactive oxygen species (ROS may be attributed to the high amount of hydrophilic phenolics. In DPPH radical scavenging assay the IC50 value of the extract was found to be 100.53 μg/mL while ascorbic acid had the IC50 value 58.92 μg/mL. Moreover, I. coccinea extract showed strong reducing power and total antioxidant capacity.
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Evaluation of antioxidant activity of Melittis melissophyllum L. extracts
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Grujić Slavica M.
2014-01-01
Full Text Available The antioxidant activities of methanol and ethanol (10%, 30%, 50% and 96% extracts of the aerial parts of Melittis melissophyllum L. were determined by DPP H, ABTS and FRAP assays. The content of flavonoids and phenols was also investigated. The total phenolic content in the extracts was determined using Folin-Ciocalteu assay; their amounts ranged between 63.5 and 111.7 mg GAeqv/g, while the concentrations of flavonoids were from 7.33 to 56.00 mg Queqv/g. IC50 values of the DPP H scavenging effect were from 0.109 to 0.664 mg/mL. The DPP H scavenging effect of the extracts was determined and the obtained IC50 values were from 0.109 to 0.664 mg/mL of solution. The values of ABTS radical activity were from 0.45 to 0.89 mg ascorbic acid/g. The FRAP value was within the range 0.160-0.382 mmol Fe/mg. The obtained values were analyzed by means of multivariate analysis, employing a hierarchical cluster analysis and between-groups linkage. The presented results confirmed that M. melissophyllum possesses good antioxidant properties and may serve as a promising source of natural antioxidants. [Projekat Ministarstva nauke Republike Srbije, br. 173029
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Inhibition of melanogenesis and antioxidant properties of Magnolia grandiflora L. flower extract
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Huang Huey-Chun
2012-06-01
Full Text Available Abstract Background Magnolia grandiflora L. flower is wildly used in Asian as a traditional herbal medication. The purpose of the study was to investigate the antimelanogenic and antioxidant properties of Magnolia grandiflora L. flower extract. In the study, the inhibitory effects of M. grandiflora L. flower extract on mushroom tyrosinase, B16F10 intracellular tyrosinase activity and melanin content were determined spectrophotometrically. Meanwhile, the antioxidative capacity of the flower extract was also investigated. Results Our results revealed that M. grandiflora L. flower extract inhibit mushroom tyrosinase activity (IC50 =11.1%; v/v, the flower extract also effectively suppressed intracellular tyrosinase activity (IC50 = 13.6%; v/v and decreased the amount of melanin (IC50 = 25.6%; v/v in a dose-dependent manner in B16F10 cells. Protein expression level of tyrosinase and tyrosinase-related protein 1 (TRP-1 were also decreased by the flower extract. Additionally, antioxidant capacities such as ABTS+ free radical scavenging activity, reducing capacity and total phenolic content of the flower extract were increased in a dose-dependent pattern. Conclusions Our results concluded that M. grandiflora L. flower extract decreased the expression of tyrosinase and TRP-1, and then inhibited melanogenesis in B16F10 cells. The flower extract also show antioxidant capacities and depleted cellular reactive oxygen species (ROS. Hence, M. grandiflora L. flower extract could be applied as a type of dermatological whitening agent in skin care products.
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Allelopathic effect of medicinal plant Cannabis sativa L. on Lactuca sativa L. seed germination
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Homa MAHMOODZADEH
2015-11-01
Full Text Available In order to examine allelopathic effect of Cannabis sativa L. on germination capability and seedling growth of Lactuca sativa L., a study was performed in laboratory conditions. Treatments were set up in randomised block design in four replications for each of four concentration ranges of 25, 50, 75 and 100 % of aqueous extract made of shoot parts and 4 identical extract concentrations made of root of cannabis. Control variant was lettuce seed treated by distilled water. During the studies shoot and seminal root length of lettuce seedlings were measured after treatments with different concentrations of extracts made of root and shoot parts of cannabis, and the obtained values were compared with the control. The obtained results suggest that the extract from the shoot parts of cannabis in high concentrations of 75 and 100 % had inhibiting effect to the germination indices while the extract from the root had no statistically significant effect on germination of lettuce seeds. Extract made of root part of cannabis showed also stimulatory effect to shoot and seminal root length of lettuce seedlings in extract concentrations of 50, 75 and 100 %.
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Touihri, Imen; Boukhris, Maher; Marrakchi, Naziha; Luis, José; Hanchi, Belgacem; Kallech-Ziri, Olfa
2015-01-01
Allium roseum L. (Alliaceae) endemic mediterranean specie was represented in the North Africa by 12 different taxa. In the present study, chemical composition, antiproliferative, antioxidant and antimicrobial activities of the essential oil extracted from A. roseum var. grandiflorum Briq. bulbs collected in the North of Tunisia were investigated. Chemical characterization has shown methyl methanethiosulfinate as major sulphurous compounds. A. roseum bulbs essential oil provides interesting antiproliferative activity against two human colonic adenocarcinoma HT29 and CACO2 cell lines in dose-dependent manner with a half-maximal inhibition (IC50) of 4.64 µg/mL and 8.22 µg/mL respectively. The antioxidant activity, as determined by FRAP assay, was 285 µmol equivalent Trolox/g of essential oil. The scavenging effect on DPPH radicals of essential oil was estimated as IC50 values at 156 µg/mL. The inhibition of superoxide anion production in a model of cancer cell lines was significant for both lines HT29 and CACO2 with IC50 of 20.25 µg/mL and 29.12 µg/mL respectively. Allium roseum essential oil exhibited antibacterial and antifungal activities with a high effectiveness against Candida albicans given by an MIC value of 0.019 mg/mL. This biological effect appears to be related mainly to the presence of organosulfur compounds.
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ALCALOIDES ACRIDÔNICOS INIBEM CATEPSINA L E V
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Emerson F. Marques
2016-01-01
Full Text Available Cathepsins represent a class of enzymes that has the primary function of randomly degrading proteins in the lysosomes, although are also involved in different pathologies. The aim of this paper was to evaluate the capacity of acridone alkaloids isolated from Swinglea glutinosa (Rutaceae to inhibit cathepsin L in vitro . The IC50 values found were in the 0.8-57 µM range and the most promising compounds were alkaloids 1 and 2, with IC50 of 0.9 and 0.8 µM, respectively. Enzyme kinetics revealed that they are reversible competitive inhibitors with respect to the substrate Z-FR-MCA. This small series of acridone alkaloids showed low selectivity for both cathepsins, but represent promising lead candidates for the further development of competitive cathepsin L and V inhibitors.
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Platinum bioaccumulation by mustard plants (Sinapis alba L.)
International Nuclear Information System (INIS)
Hawienczyk, M.; Bystrzejewska-Piotrowska, G.; Kowalska, J.; Asztemborska, M.
2005-01-01
The ability of hydroponically cultivated Indian mustard plants (Sinapis alba L.) to accumulate platinum was investigated. The Pt-bioaccumulation in leaves, stem and shoots of plants growing for 2 and 4 weeks at Pt-concentration of 50 and 500 μg/L was compared. The relation between dry and fresh weight was also estimated. Adsorptive stripping voltammetry (AdSV) and mass spectrometry with inductively coupled plasma (ICP-MS) were applied for determination of Pt. Increasing Pt-concentration from 50 to 500 μg/L in the medium causes: (1) reduction of the root tissue hydration level at unchanged modification in aboveground parts of the plants and (2) decrease of the Pt transfer factor (TF) for roots and increase for leaves and stem. Duration of the culture influenced on Pt-accumulation in roots and in aboveground organs of mustard plants. Transfer factor for Pt between 560 and 1600 makes Indian mustard plants one at Pt-hyperaccumulators. Distribution of Pt-bioaccumulation in the plant organs may be useful for biomonitoring of platinum in the environment. (author)
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Chemical composition, antioxidative and antimicrobial activity of essential oil Ocimum sanctum L.
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Beatović Damir V.
2013-01-01
Full Text Available Ocimum sanctum L. (Lamiaceae sin. Ocimum tenuiflorum L. or Tulsi basil is a plant originating from tropical and subtropical areas of India. It is used in both the traditional and official medicine in India. Tulsi is a type of basil that is insufficiently explored and studied in Europe. The goal of this paper is to determine the chemical composition, antioxidative, and antimicrobial activity of the essential oil Ocimum sanctum L. grown in Serbia. The quantity of essential oil in 100 g of herb (v/w is 0.68%, with 41 components identified in the tested essential oil. The most represented chemical group are sesquiturpene hydrocarbonates with 80.47%. Other groups were much less represented. Sesquiturpene hydrocarbonate β-cariophyllene is a predominant component in the essential oil with 63.80%. The quantity of tested essential oil needed to achieve 50% of inhibition of DPPH radicals is 0.35 μg/ml, and it has high potential to neutralize free radicals. The essential oil exhibited antibacterial activity to all tested strains of bacteria, both Gram-positive and Gram-negative. It affected all strains in an inhibitory way in the interval 0.34-41.50 μl/ml, and in a bactericide way within the range 22.50-124.5 μl/ml. The most sensitive strains of bacteria are Salmonella typhimurium and Escherichia coli, while Listeria monocytogenes and Enterococus faecalis showed greatest resistance. The essential oil exhibited antifugal activity on all tested fungi. It affected all tested fungi in an inhibitory way in the interval 4.42-8.83 μl/ml, and in a microbicide way within the range 10.00-50.00 μl/ml. The most sensitive fungi are: Aspergillus ochraceus, Penicillium ochrochloron and Penicilium funiculosum, while the most resistent one is Aspergillus niger. The tested basil essential oil Ocimum sanctum demonstrated significant antioxidative and antimicrobial effect and may be used as a raw material in food, pharmaceutical and chemical industries.
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Valine-spectrophotometric readout dosimeter (1 Gy-50 kGy)
International Nuclear Information System (INIS)
Nilekani, S.R.; Gupta, B.L.
2005-01-01
In this method 20 mg unirradiated/irradiated L-valine powder [(CH 3 ) 2 CH.NH 2 CH.COOH] is dissolved in 10 ml of a solution containing 4x10 -4 mol dm -3 Fe 2+ and 2.5x10 -4 mol dm -3 xylenol orange (XO) in aerated aqueous 0.060 mol dm -3 sulphuric acid (FX). The plot of absorbance at 550 nm against dose is non linear. A dose of 1-50 kGy can be measured. However, dosimeter can be sensitized in the dose range of 1 to 16 kGy by dissolving 50-mg valine powder in 10 ml of a solution which contains 5x10 -4 mol dm -3 Fe 2+ and 3x10 -4 mol dm -3 XO in aerated aqueous 0.065 mol dm -3 sulphuric acid. The plot of absorbance at 549 nm against dose is non-linear. However, dosimeter shows linear response when 500 mg unirradiated/irradiated L-valine powder is dissolved in 10 ml of a solution containing 7.5x10 -4 mol dm -3 Fe 2+ and 3x10 -4 mol dm -3 XO in aerated aqueous 0.25 mol dm -3 sulphuric acid. The plot of absorbance at 557 nm against dose is linear in the dose range of 20-400Gy and doses down to about 1 Gy can be measured using 10-cm path cells. Response of the dosimeter is independent of irradiation temperature in the temperature range 20-50 deg C. Irradiated valine powder is stable for about 1 month. The reproducibility of the method is better than ±2%. This dosimeter is very useful as transfer dosimeter for food irradiation and radiation sterilization
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Antiproliferative Effects of Cynara cardunculus L. var. altilis (DC Lipophilic Extracts
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Patrícia A. B. Ramos
2016-12-01
Full Text Available Besides being traditionally used to relieve hepatobiliary disorders, Cynara cardunculus L. has evidenced anticancer potential on triple-negative breast cancer (TNBC. This study highlights the antiproliferative effects of lipophilic extracts from C. cardunculus L. var. altilis (DC leaves and florets, and of their major compounds, namely cynaropicrin and taraxasteryl acetate, against MDA-MB-231 cells. Our results demonstrated that MDA-MB-231 cells were much less resistant to leaves extract (IC50 10.39 µg/mL than to florets extract (IC50 315.22 µg/mL, during 48 h. Moreover, leaves extract and cynaropicrin (IC50 6.19 µg/mL suppressed MDA-MB-231 cells colonies formation, via an anchorage-independent growth assay. Leaves extract and cynaropicrin were also assessed regarding their regulation on caspase-3 activity, by using a spectrophotometric assay, and expression levels of G2/mitosis checkpoint and Akt signaling pathway proteins, by Western blotting. Leaves extract increased caspase-3 activity, while cynaropicrin did not affect it. Additionally, they caused p21Waf1/Cip1 upregulation, as well as cyclin B1 and phospho(Tyr15-CDK1 accumulation, which may be related to G2 cell cycle arrest. They also downregulated phospho(Ser473-Akt, without changing total Akt1 level. Cynaropicrin probably contributed to leaves extract antiproliferative action. These promising insights suggest that cultivated cardoon leaves lipophilic extract and cynaropicrin may be considered toward a natural-based therapeutic approach on TNBC.
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Energy Technology Data Exchange (ETDEWEB)
NONE
2008-11-15
This document presents the 50 measures decided by the government to develop the renewable energies in France and reach the 20% of participation to the energy production in 2020. Some measures concern all the renewable energies, they deal with the regulation, the administrative procedures of the building, others are specific to each energy. (A.L.B.)
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Development of L-band pillbox RF window
International Nuclear Information System (INIS)
Takeuchi, Y.; Fukuda, S.; Hisamatsu, H.; Saito, Y.; Takahashi, A.
1994-01-01
A pillbox RF output window was developed for the L-band pulsed klystron for the Japanese Hadron Project (JHP) 1-GeV proton linac. The window was designed to withstand a peak RF power of 6 MW, where the pulse width is 600 μsec and the repetition rate is 50 Hz. A high power model was fabricated using an alumina ceramic which has a low loss tangent of 2.5x10 -5 . A high power test was successfully performed up to a 113 kW RF average power with a 4 MW peak power, a 565 μsec pulse width and a 50 Hz repetition rate. By extrapolating the data of this high power test, the temperature rise of the ceramic is estimated low enough at the full RF power of 6 MW. Thus this RF window is expected to satisfy the specifications of the L-band Klystron. (author)
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Directory of Open Access Journals (Sweden)
Sarah Brandão Santa Cruz Barboza
2009-01-01
Full Text Available A capacidade regenerativa de gemas axilares de abacaxizeiro cv. Pérola (Ananas comosus (L. Merr. foi avaliada em meio de cultivo líquido e gelificado, na presença e ausência de luz, com o objetivo de produzir material para subsequentes fases da micropropagação. Os explantes foram estabelecidos, por 60 dias, em meio MS acrescido de 0,63 μM de ANA e 2,5 μM de BAP. O delineamento experimental foi inteiramente casualizado, constituído com quatro tratamentos (meio líquido com e sem ponte de papel de filtro e meio gelificado com ágar a 6,0 g L-1 e com Phytagel® a 3,0 g L-1, com quatro repetições e cinco explantes por repetição. Diferentes volumes de meio líquido (2,5 mL; 5,0 mL e 10,0 mL também foram avaliados, usando-se quatro repetições por volume de meio de cultura. Maior número de brotos foi obtido na presença de luz, em meio líquido sem ponte de papel de filtro, onde 80% dos explantes se diferenciaram em brotos. Na ausência de luz, 68,8% a 87,5% dos explantes não regeneraram brotos. Explantes cultivados em volumes de 5,0 mL ou 2,5 mL de meio MS líquido, acrescido de 0,63 μM de ANA e 2,5 μM de BAP, na presença de luz, constitui um protocolo adequado para cultivo inicial de gemas axilares e regeneração de brotos de abacaxizeiro.The regenerative capacity of buds from lateral sprouts of the pineapple cv. Pérola (Ananas comosus (L. Merr. was evaluated in liquid and semi-solid medium, under light and dark conditions, with the objective of producing materials for subsequent phase of micropropagation. The explants were established for 60 days in basal MS medium, supplemented with 0.63 μM NAA and 2.5 μM BAP. The statistical design was completely randomized with four treatments (liquid medium with and without filter paper bridge, and semi-solid medium gellified with agar and phytagel®, four repetitions and five explants per experimental unit. Different volumes of liquid medium (2.5 mL, 5.0 mL, and 10.0 mL were also
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Directory of Open Access Journals (Sweden)
Malek Besbes Hlila
2017-11-01
Full Text Available Objective: To determine the larvicidal activity of sixteen extracts of Scabiosa arenaria Forssk. (S. arenaria against the third instar larvae of Culex pipiens L. (C. pipiens. Methods: Larvicidal activity of S. arenaria extracts was determined according to World Health Organization. Twenty third instars of the C. pipiens were exposed to different concentrations (15 µg/mL to 60 µg/mL of extracts. Mortality was recorded after 24 h of exposure. Results: The roots ethyl acetate fraction of S. arenaria had a significant toxic effect on larvae of C. pipiens, with high mortality percentage (100.0% ± 2.2% at 60 µg/mL, and 50% lethal concentration value of LC50 = (15.00 ± 0.09 µg/mL. Conclusions: Results show that roots ethyl acetate could be used for the production of natural bio-pesticides which could decrease our dependence on chemical pesticides.
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Lipka, Aleksandra; Majewska, Marta; Panasiewicz, Grzegorz; Bieniek-Kobuszewska, Martyna; Szafranska, Bozena
2017-09-01
The pregnancy-associated glycoprotein-like family (PAG-L) is a large group of chorionic products, expressed in the pre-placental trophoblast and later in the post-implantational chorionic epithelium, and are involved in proper placenta development and embryo-maternal interaction in eutherians. This study describes identification of the PAG-L family in the genome of the Eurasian beaver (Castor fiber L.), named CfPAG-L. We identified 7657 bp of the CfPAG-L gDNA sequence (Acc. No. KX377932), encompassing nine exons (1-9) and eight introns (A-H). The length of the CfPAG-L exons (59-200 bp) was equivalently similar to the only known counterparts of bPAG1, bPAG2, and pPAG2. The length of the CfPAG-L introns ranged 288-1937 bp and was completely different from previously known PAG introns. The exonic CfPAG-L regions revealed 50.3-72.9% homology with equivalent segments of bPAG1 and pPAG2 structure. The intronic CfPAG-L regions alignments revealed a lack of homology. Within the entire CfPAG-L gene, 31 potential single nucleotide variants (SNV: 7 transversions and 24 transitions) were predicted. The identified exonic polymorphic loci did not affect the amino acid sequence of the CfPAG-L polypeptide precursor. This is the first report describing the CfPAG-L gene sequence, structural organization, and SNVs in the Eurasian beaver, one of the largest rodents.
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International Nuclear Information System (INIS)
Dietrich, R.
1979-01-01
The ANIPLO-D50 code plots the location-dependent scalar flow calculated with the ANISN Sn program. The scalar flows punched on cards by the ANISN program are part of the input of ANIPLO-D50. They can be read by ANIPLO-D50 directly in the mode chosen in ANISN where signs, mantissa, and exponents are distinguished. The ANIPLO-D50 program also permits plotting of the dose rate distribution. The ANIPLO-D50 code is written in FORTRAN IV. (orig.) [de
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Directory of Open Access Journals (Sweden)
Zhao Xin
2015-01-01
Full Text Available Vaccination is an effective strategy to prevent leptospirosis, a global zoonotic disease caused by infection with pathogenic Leptospira species. However, the currently used multiple-valence vaccine, which is prepared with whole cells of several Leptospira serovars, has major side effects, while its cross-immunogenicity among different Leptospira serovars is weak. LipL32, LipL21 and 2 OmpL1 have been confirmed as surface-exposed antigens in all pathogenic Leptospira strains, but their immunoprotective efficiency needs to be improved. In the present study, we generated a fusion gene lipL32/1-lipL21-ompL1/2 using primer-linking PCR and an engineered E. coli strain to express the recombinant fusion protein rLipL32/1-LipL21-OmpL1/2 (rLLO. Subsequently, the expression conditions were optimized using a central composite design that increased the fusion protein yield 2.7-fold. Western blot assays confirmed that rLLO was recognized by anti-rLipL32/1, anti-rLipL21, and anti-rOmpL1/2 sera as well as 98.5% of the sera from leptospirosis patients. The microscopic agglutination test (MAT demonstrated that rLLO antiserum had a stronger ability to agglutinate the strains of different Leptospira serovars than the rLipL32/1, rLipL21, and rOmpL1/2 antisera. More importantly, tests in hamsters showed that rLLO provided higher immunoprotective rates (91.7% than rLipL32/1, rLipL21 and rOmpL1/2 (50.0-75.0%. All the data indicate that rLLO, a recombinant fusion protein incorporating three antigens, has increased antigenicity and immunoprotective effects, and so can be used as a novel immunogen to develop a universal genetically engineered vaccine against leptospirosis.
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Directory of Open Access Journals (Sweden)
Elisalva T. Guimarães
2010-12-01
Full Text Available Physalis angulata L., Solanaceae, is an annual herb commonly used in popular medicine in many tropical and subtropical countries. P. angulata extracts contain a variety of substances, but little is known about their pharmacological activities. In this work we investigated the in vitro antileishmanial activity of seco-steroids (physalins purified from P. angulata. Addition of physalins B, F, and G caused a concentration-dependent inhibition in the growth of L. amazonensis promastigotes, being the IC50 values were 6.8, 1.4, and 9.2 μM, respectively. Physalin D was less active and had an IC50 value of 30.5 μM. Physalins were also active in cultures of other Leishmania species (L. major, L. braziliensis, and L. chagasi. Our results demonstrate the potent antileishmanial activity of physalins in cultures of Leishmania species of the New and Old Worlds and suggest the therapeutic potential of these seco-steroids in leishmaniasis.Physalis angulata L., Solanaceae, é uma erva anual utilizada na medicina popular em muitos países tropicais e subtropicais. Apesar dos extratos da P. angulata apresentarem uma grande variedade de substâncias, pouco é conhecido sobre a sua atividade farmacológica. Neste trabalho foi investigado a atividade antileishmania in vitro de seco-esteroides (fisalinas purificados da P. angulata. O tratamento com as fisalinas B, F e G causou uma inibição concentração-dependente do crescimento de promastigotas de Leishmania amazonensis em cultura axênica, com valores de IC50 de 6,8, 1,4, e 9,2 μM respectivamente. A fisalina D foi menos ativa, com valores de IC50 de 30,5 μM. Foi também observada uma atividade leishmanicida em culturas de outras espécies de Leishmania (L. major, L. braziliensis e L. chagasi. Nossos resultados demonstram que as fisalinas inibem o crescimento dos promastigotas com o tratamento de espécies de Leishmania do Velho e do Novo Mundos e sugerem o potencial terapêutico destas moléculas na
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Okunade, O. A.; Ghawi, S. K.; Methven, Lisa; Niranjan, Keshavan
2015-01-01
This study investigates the effects of temperature and pressure on inactivation of myrosinase extracted from black, brown and yellow mustard seeds. Brown mustard had higher myrosinase activity (2.75 un/mL) than black (1.50 un/mL) and yellow mustard (0.63 un/mL). The extent of enzyme inactivation increased with pressure (600-800 MPa) and temperature (30-70 °C) for all the mustard seeds. However, at combinations of lower pressures (200-400 MPa) and high temperatures (60-80 °C), there was less i...
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DEFF Research Database (Denmark)
Rud, Ida; Solem, Christian; Jensen, Peter Ruhdal
2008-01-01
The hydrolytic F-1-part of the F1F0-ATPase was over-expressed in Lactobacillus (L.) plantarum NC8 and L. sakei Lb790x during fermentation of glucose or ribose, in order to study how changes in the intracellular levels of ATP and ADP affect the metabolic fluxes. The uncoupled ATPase activity...... resulted in a decrease in intracellular energy level (ATP/ADP ratio), biomass yield and growth rate. Interestingly, the glycolytic and ribolytic flux increased in L. plantarum with uncoupled ATPase activity compared to the reference strain by up to 20% and 50%, respectively. The ATP demand was estimated...... to have approximately 80% control on both the glycolytic and ribolytic flux in L. plantarum under these conditions. In contrast, the glycolytic and ribolytic flux decreased in L. sakei with uncoupled ATPase activity. (C) 2008 Elsevier Inc. All rights reserved....
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L-histidine enhances learning in stressed zebrafish
Directory of Open Access Journals (Sweden)
L.P.V. Cofiel
2009-01-01
Full Text Available The aim of the present study was to determine the effect of the histaminergic precursor L-histidine and the H3 receptor antagonist thioperamide on the learning process of zebrafish submitted or not to confinement stress. On each of the 5 consecutive days of experiment (D1, D2, D3, D4, D5, animals had to associate an interruption of the aquarium air supply with food offering. Non-stressed zebrafish received an intraperitoneal injection of 100 mg/kg L-histidine, 10 mg/kg thioperamide or saline after training. Stressed animals received drug treatment and then were submitted to confinement stress for 1 h before the learning procedure. Time to approach the feeder was measured (in seconds and was considered to be indicative of learning. A decrease in time to approach the feeder was observed in the saline-treated group (D1 = 141.92 ± 13.57; D3 = 55 ± 13.54, indicating learning. A delay in learning of stressed animals treated with saline was observed (D1 = 217.5 ± 25.66. L-histidine facilitated learning in stressed (D1 = 118.68 ± 13.9; D2 = 45.88 ± 8.2 and non-stressed (D1 = 151.11 ± 19.20; D5 = 62 ± 14.68 animals. Thioperamide inhibited learning in non-stressed (D1 = 110.38 ± 9.49; D4 = 58.79 ± 16.83 and stressed animals (D1 = 167.3 ± 26.39; D5 = 172.15 ± 27.35. L-histidine prevented the increase in blood glucose after one session of confinement (L-histidine = 65.88 ± 4.50; control = 53 ± 3.50 mg/dL. These results suggest that the histaminergic system enhances learning and modulates stress responses in zebrafish.
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Lürling, M.F.L.L.W.; Faassen, E.J.; Eenennaam, van J.S.
2011-01-01
In short-term tests and chronic life table assays, Daphnia magna was exposed to the cyanobacterial neurotoxic non-protein amino acid ß-N-methylamino-l-alanine (BMAA). BMAA was not acutely lethal to Daphnia (LC50–48h > 10 000 µg L-1), but reduced mobility (IC50–48h 40 µg L-1) and affected life
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Effects of passing electric current on the elastic property of amorphous Cu50Zr50 and Cu50Ti50
International Nuclear Information System (INIS)
Takemoto, R.; Nagata, M.; Mizubayashi, H.
1996-01-01
For both amorphous Cu 50 Zr 50 and Cu 50 Ti 50 , the dynamic Young's modulus M was found to increase under passing electric d.c.-current (PEC) with the current density i d below 5 x 10 3 A/cm 2 , suggesting that PEC induces internal stress. The i d dependence of M observed at low strain amplitude ε t was found to be identical to the ε t dependence of M without PEC after scaling between i d and ε t , giving Z* in the order of 10 5 , where Z* is the apparent charge number measuring the electromigration force (EM-force) under PEC. The authors surmise that such a large Z* reflects the concentration of EM-force through the collective motion of many atoms, Z* = z*ξ, for ξ atoms with the charge number z* per atom. Application of this view to the observed effect of annealing on Z* gives ξ as several hundreds in the as-quenched state. Based on the present results, the effects of PEC on the structural relaxation and crystallization processes reported are also discussed
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The energy levels and oscillator strength of a complex atom--Au50+ in a self-consistent potential
International Nuclear Information System (INIS)
Feng Rong; Zou Yu; Fang Quanyu
1998-01-01
The effects of free electrons in a plasma on a complex atom are discussed, here the authors are interested in the target ion--Au 50+ in inertia confined fusion (ICF). The results are compared with those in the case of hydrogenic ions. Accurate numerical solutions have been obtained for Schroedinger's equation through Debye screened Hartree-Fock-Slater self-consistent potential. Solutions have been computed for 28 eigenstates, 1s through n =3D 7, l =3D 6, yielding the energy eigenvalues for a wide range of Debye screening length Λ. As in the case of hydrogenic ions, under screening, all energy levels are shifted away from their unscreened values toward the continuum, that is, the ionization limits are shifted downward. Conclusions have been made that when Λ>5a 0 , that is, in the weak screening cases, Debye screening has little effect on oscillator strength, average orbital radius, transition matrix elements, etc., of Au 50+ . For each (n,l) eigenstate, there is a finite value of screening length Λ 0 (n,l), for which the energy becomes zero. When Λ is sufficiently small, level crossing appears at high n states. Optical oscillator strength for Au 50+ has also been calculated, the results are compared with those under unscreened potential
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Herbs containing L- Dopa: An update.
Ramya, Kuber B; Thaakur, Santhrani
2007-07-01
L-Dopa is the drug of choice in the treatment of Parkinson's disease but it has dose related adverse effects such as nausea, vomiting, orthostatic hypotension, end of dose deterioration, on off phenomena and on chronic therapy motor complications synonymous to parkinsonism. Mucuna pruriens (M.P) commonly known as velvet beans or cowitch are used in case of spasms associated with Parkins onism. Clinical efficacy of seeds of this plant was confirmed and the efficacy was contributed to its L-Dopa content. M.P extract showed twice the antiparkinsonism activity compared with synthetic L-Dopa. There is sufficient L-Dopa in broad bean (Vicia faba) pods. One study proved its efficacy in Parkinsonism. Ginkgo biloba extract showed protective effect in vivo and invitro. 50% ethanolic extract of Plumbago zeylanica was effective in rats. The following plants were reported to have L-Dopa but their protective effect is yet to be established in animal models. Vigna aconitifolia, Vigna unguiculata, Vigna vexillata, Prosopis chilensis, Pileostigma malabarica, Phanera vahlis, Parkinsonia acculeata, Macuna urens, Canvavalia glandiata, Cassia floribanda, Casia hirsute and Dalbergia retusa etc.
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International Nuclear Information System (INIS)
Vijaysri, Sangeetha; Talasela, Latha; Mercer, Andrew A.; Mcinnes, Colin J.; Jacobs, Bertram L.; Langland, Jeffrey O.
2003-01-01
Orf virus (OV), the prototypic parapoxvirus, is resistant to the effects of interferon (IFN) and this function of OV has been mapped to the OV20.0L gene. The protein product of this gene shares 31% amino acid identity to the E3L-encoded protein of vaccinia virus (VV) that is required for the broad host range and IFN-resistant phenotype of VV in cells in culture and for virulence of the virus in vivo. In this study we investigated whether the distantly related OV E3L homologue could complement the deletion of E3L in VV. The recombinant VV (VV/ORF-E3L) expressing the OV E3L homologue in place of VV E3L was indistinguishable from wt VV in its cell-culture phenotype. But VV/ORF-E3L was over a 1000-fold less pathogenic than wt VV (LD 50 > 5 x 10 6 PFU, compared to LD 50 of wtVV = 4 x 10 3 PFU) following intranasal infection of mice. While wt VV spread to the lungs and brain and replicated to high titers in the brain of infected mice, VV/ORF-E3L could not be detected in the lungs or brain following intranasal infection. VV/ORF-E3L was at least 100,000-fold less pathogenic than wt VV on intracranial injection. Domain swap experiments demonstrate that the difference in pathogenesis maps to the C-terminal domain of these proteins. This domain has been shown to be required for the dsRNA binding function of the VV E3L
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Directory of Open Access Journals (Sweden)
Mohd. Sayeed Akthar
2014-09-01
, while, it was found at concentration of 50.0 mg/mL for petroleum ether and aqueous leaf extract of P. nigrum and C. didymobotyra. However, the MIC of methanol leaf extracts of P. nigrum and ethanol and methanol leaf extracts P. nigrum and C. didymobotyra for Aspergillus spp. was recorded at concentration of 12.5 mg/mL, while, the MIC concentration ranged from 25.0-50.0 mg/ mL for other tested solvent leaf extract of P. nigrum and C. didymobotyra. Conclusions: This study suggests that test plants could be potential candidates for developing the new antimicrobial drugs against the wide range of pathogenic bacteria and fungal strains.
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Magnetic hardening of Fe{sub 50}Co{sub 50} by rotary swaging
Energy Technology Data Exchange (ETDEWEB)
Gröb, T., E-mail: t.groeb@phm.tu-darmstadt.de [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Wießner, L. [Institute for Production Engineering and Forming Machines, Otto-Berndt-Str. 2, 64287 Darmstadt (Germany); Bruder, E. [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Faske, T.; Donner, W. [Divison Structure Research, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Groche, P. [Institute for Production Engineering and Forming Machines, Otto-Berndt-Str. 2, 64287 Darmstadt (Germany); Müller, C. [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany)
2017-04-15
Fe{sub 50}Co{sub 50} was subjected to incremental forming by rotary swaging with the aim of tailoring the coercivity by changing the microstructure. The challenging part of a deformation of Fe{sub 50}Co{sub 50} is an ordering phase present at room temperature, leading to low formability. To increase the formability of the alloy the presence of the ordering phase was supressed by two different concepts. The first concept consists of a heat treatment above the phase transition followed by rapid cooling and deformation at room temperature. The second concept was rotary swaging at temperatures above the phase transition temperature. A comparison in terms of resulting microstructure and magnetic properties shows that both concepts have a potential for tailoring the coercivity of Fe{sub 50}Co{sub 50}. - Highlights: • Magnetic hardening of Fe{sub 50}Co{sub 50} was achieved by rotary swaging with two different concepts. • The influences of the microstructural changes during the rotary swaging process have been linked to magnetic hardening. • Increase in coercivity for Fe{sub 50}Co{sub 50} by rotary swaging at elevated temperature is limited by the dynamic restoration. • Coercivity of Fe{sub 50}Co{sub 50} can be tailored by the induced plastic strain.
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Directory of Open Access Journals (Sweden)
Laura Cornara
2018-01-01
Full Text Available Seagrasses are high plants sharing adaptive metabolic features with both terrestrial plants and marine algae, resulting in a phytocomplex possibly endowed with interesting biological properties. The aim of this study is to evaluate the in vitro activities on skin cells of an ethanolic extract obtained from the leaves of Posidonia oceanica (L. Delile, family Potamogetonaceae, herein named Posidonia ethanolic extract (PEE. PEE showed high radical scavenging activity, high phenolic content, and resulted rich in chicoric acid, as determined through HPLC-MS analysis. The use of MTT assay on fibroblasts showed a PEE cytotoxicity threshold (IC05 of 50 µg/mL at 48 h, while a sub-toxic dose of 20 µg/mL induced a significant increase of fibroblast growth rate after 10 days. In addition, an ELISA assay revealed that PEE doses of 5 and 10 µg/mL induced collagen production in fibroblasts. PEE induced dose-dependent mushroom tyrosinase inhibition, up to about 45% inhibition at 1000 µg/mL, while 50% reduction of melanin was observed in melanoma cells exposed to 50 µg/mL PEE. Finally, PEE lipolytic activity was assessed by measuring glycerol release from adipocytes following triglyceride degradation. In conclusion, we have collected new data about the biological activities of the phytocomplex of P. oceanica seagrass on skin cells. Our findings indicate that PEE could be profitably used in the development of products for skin aging, undesired hyperpigmentation, and cellulite.
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Directory of Open Access Journals (Sweden)
Olga Osorio Rojas
2007-04-01
Full Text Available El análisis de endotoxina por medio del lisado de amebocitos de Limulus (LAL es uno de los principales ensayos en el control de calidad de la fabricación de inyectables por su repercusión en la salud humana y animal, razón por la que se requiere la validación de la técnica para los productos parenterales. Se empleó el método de LAL gel-clot para validar la detección de endotoxina bacteriana en la oxitetraciclina producida por un laboratorio maquilador de productos farmacéuticos veterinarios de Bogotá, Colombia. Para este objetivo se tomaron muestras al inicio, intermedio y final de 3 lotes diferentes del medicamento y se realizó la prueba de validación tal y como lo especifica la United States Pharmacopea XXV. Los resultados para la máxima dilución válida del producto (1:80 de la prueba Spike mostraron el 100 % de inhibición hasta la dilución 1:16 y 0 % de inhibición en las siguientes diluciones. En la prueba Unspike se muestra un realce de la prueba a partir de la dilución 1:32. El rótulo para un reactivo de LAL con sensitividad (l de 0,25 unidades de endotoxinas por mililitro (UE/mL y el operario que realizó el ensayo quedaron validados.The endotoxin analysis by the Limulus amebocyte lysate (LAL assay is one of the main tests in the quality control of the manufacture of injectables due to their repercussion on human and animal health. That's why the validation of the technique is required for parenteral products. The LAL gel-clot method was used to validate the detection of bacterial endotoxin in the oxytetracycline produced by a veterinary pharmaceutical laboratory of Bogota-Colombia. To this end, samples were taken at the beginning, interval and end of 3 different batches of the medicine and the test of validation was made just as it is specified in the United States Pharmacopea XXV. The results for the Maximum Valid Dilution of the product (1:80 of the Spike test showed a 100 % of inhibition until dilution 1:16, and 0
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ICECAP: an integrated, general-purpose, automation-assisted IC50/EC50 assay platform.
Li, Ming; Chou, Judy; King, Kristopher W; Jing, Jing; Wei, Dong; Yang, Liyu
2015-02-01
IC50 and EC50 values are commonly used to evaluate drug potency. Mass spectrometry (MS)-centric bioanalytical and biomarker labs are now conducting IC50/EC50 assays, which, if done manually, are tedious and error-prone. Existing bioanalytical sample preparation automation systems cannot meet IC50/EC50 assay throughput demand. A general-purpose, automation-assisted IC50/EC50 assay platform was developed to automate the calculations of spiking solutions and the matrix solutions preparation scheme, the actual spiking and matrix solutions preparations, as well as the flexible sample extraction procedures after incubation. In addition, the platform also automates the data extraction, nonlinear regression curve fitting, computation of IC50/EC50 values, graphing, and reporting. The automation-assisted IC50/EC50 assay platform can process the whole class of assays of varying assay conditions. In each run, the system can handle up to 32 compounds and up to 10 concentration levels per compound, and it greatly improves IC50/EC50 assay experimental productivity and data processing efficiency. © 2014 Society for Laboratory Automation and Screening.
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Directory of Open Access Journals (Sweden)
NI NENGAH DARMIATI
2015-09-01
Full Text Available The Activity Test of Celery Leaf Extract (Apium graveolens L. Against Bean Weevil, Callosobruchus cinensis L. (Coleoptera:Bruchidae The experiment was conducted at the Laboratory of Plant Pest and Disease Management,Department of Agroecotechnology, Faculty of Agriculture, Udayana University. The purpose of this experiment was to examine the activity of celery leaf extract against bean weevil, Callosobruchus chinensis L. The experiment was Randomized Complete Design, with five treatments of formulation concentration. The activities of celery leaf extract was indicated through i.e. contact poison test, repellent test, and the placement of eggs (oviposition test. The results showed that the celery leaf extract has activity as a contact poison with concentration 75% formulations caused over 50% death of the total insect. The extract with 100% concentration acted as a repellent and anti oviposition as well.
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Fan, Cong; Zhang, Juan; Ouyang, Tao; Li, Jinfeng; Wang, Tianfeng; Fan, Zhaoqing; Fan, Tie; Lin, Benyao; Xie, Yuntao
2018-05-04
RAD50 is a highly conserved DNA double-strand break (DSB) repair gene. However, the associations between RAD50 germline mutations and the survival and risk of breast cancer have not been fully elucidated. Here, we aimed to investigate the clinical impact of RAD50 germline mutations in a large cohort of unselected breast cancer patients. In this study, RAD50 germline mutations were determined using next-generation sequencing in 7657 consecutive unselected breast cancer patients without BRCA1/2 mutations. We also screened for RAD50 recurrent mutations (L719fs, K994fs, and H1269fs) in 5000 healthy controls using Sanger sequencing. We found that 26 out of 7657 (0.34%) patients had RAD50 pathogenic mutations, and 16 patients carried one of the three recurrent mutations (L719fs, n=6 cases; K994fs, n=5 cases; and H1269fs, n=5 cases); the recurrent mutation rate was 0.21%. The frequency of the three recurrent mutations in the 5000 healthy controls was 0.18% (9/5000). These mutations did not confer an increased risk of breast cancer in the studied patients [odds ratios (OR), 1.16; 95% confidence interval (CI), 0.51-2.63; P = 0.72]. Nevertheless, multivariate analysis revealed that RAD50 pathogenic mutations were an independent unfavourable predictor of recurrence-free survival (RFS) [adjusted hazard ratio (HR) 2.66; 95% CI, 1.18-5.98; P=0.018] and disease-specific survival (DSS) (adjusted HR 4.36; 95% CI, 1.58-12.03; P=0.004) in the entire study cohort. Our study suggested that RAD50 germline mutations are not associated with an increased risk of breast cancer, but patients with RAD50 germline mutations have unfavourable survival compared with patients without these mutations. This article is protected by copyright. All rights reserved. © 2018 UICC.
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Dosis letal 50 de lorazepam en ratón (Mus musculus Albino, cepa suizo-icr
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Francisco Alejandro Múnera G.
2000-10-01
Full Text Available Objective: The lethal dose 50 (LD50 of lorazepam in albino mice (Musmusculus, swiss ICR strain, was determined as a first step in the study of the conjoint toxicity of admixtures of scopolamine and benzodiazepines ("new burundanga". Method: Sixty adult male mice were randomly assigned to five experimental groups and to a control one. The dose of lorazepam administered intraperitoneally to each group was: group 1,10 mg kg_1; group 11,20 mg kgI; group 111,40mg kgL; group IV,80mgkg'; group V,160mg kg-l.The control group received only the vehicle solution. Mortality was recorded during 15 days after injection. Necropsies were performed to all the mice dead during the assay and to the survivors. Data were processed using probit analysis and survival analysis. Results: Estimated LD50 were 90.71 mg kg- 1, with 95% confidence range of 65,02to 150,13mg kg- 1.Deaths occurred within the first six days after injection of doses higher than 80 mg kg:', mostly during the first 48 hours. Conclusions: The estimated LD50 of lorazepam in this experiment almost doubles the reported one, this finding suggests a higher resistance of the mice strain used in this experiment The critic period for lorazepam poisoning spans the first 48 hours.
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Response of Sitophilus granarius L. to fumigant toxicity of some plant volatile oils
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Ali F. Hamza
2016-01-01
Full Text Available One-week-old adults of Sitophilus granarius (L. reared on wheat were subjected to pure plant volatile oils of Thuja, Eucalyptus and Peppermint. Volatile oil of Thuja was extracted from unripe fruits of Thuja orientalis plant by water distillation. The objective of the current study was to determine the fumigant toxicity of these volatile oils against adults of S. granarius. The fumigant toxicity of the volatile oils was tested against 1week old adults of S. granarius at 28±2 °C and 65±5% RH in darkness. The mortality of adults was tested at different concentrations ranging from 20 to 100 μl of Thuja, 10–30 μl of Eucalyptus and 3–15 μl of Peppermint at different exposure times (24, 48 and 72 h. The results demonstrated that the mortality increased with increases in concentration and exposure periods. The percent mortality of S. granarius reached 91.2, 95.0 and 91.2% when 1-w-old adult exposed to higher concentration of Thuja, Eucalyptus and Peppermint oils, respectively, comparing to 0% in the control after 24 h. After 72 h the percent mortality was 100% at the higher concentration of the three volatile oils. LC50 and LC90 were determined for each volatile oil and each exposure period. Data probit analysis demonstrated that concentrations of 70.71 μl Thuja, 16.95 μl Eucalyptus and 10.48 μl Peppermint, recorded 50% mortality after 24 h, however it reached 90% when concentrations increased to 104.04 μl Thuja, 25.48 μl Eucalyptus and 15.92 μl Peppermint after the same period. LC50 and LC90 values were decreased by increasing the exposure periods. These results showed that the three volatile oils could be applicable to the management of populations of S. granarius (L..
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Directory of Open Access Journals (Sweden)
N. Khateri
2017-03-01
Full Text Available Objective An experiment was conducted to investigate the effects of a specific mixture of essential oils (MEO, containing thyme, clove and cinnamon EO, on rumen microbial fermentation, nutrient apparent digestibility and blood metabolites in fistulated sheep. Methods Six sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding MEO at 0 (control, 0.8, and 1.6 mL/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay:concentrate diet. Results Ruminal pH, total volatile fatty acids (VFA concentration, molar proportion of individual VFA, acetate: propionate ratio and methane production were not affected with MEO. Relative to the control, Small peptides plus amino acid nitrogen and large peptides nitrogen concentration in rumen fluid were not affected with MEO supplementation; while, rumen fluid ammonia nitrogen concentration at 0 and 6 h after morning feeding in sheep fed with 1.6 mL/d of MEO was lower (p<0.05 compared to the control and 0.8 mL/d of MEO. At 0 h after morning feeding, ammonia nitrogen concentration was higher (p<0.05 in sheep fed 0.8 mL/d of MEO relative to 1.6 mL/d and control diet. Ruminal protozoa and hyper ammonia producing (HAP bacteria counts were not affected by addition of MEO in the diet. Relative to the control, no changes were observed in the red and white blood cells, hemoglobin, hematocrit, glucose, beta-hydroxybutyric acid, cholesterol, total protein, albumin, blood urea nitrogen and aspartate aminotransferase and alanine aminotransferase concentration. Apparent total tract digestibility of dry matter, crude proten, organic matter, and neutral detergent fiber were not influenced by MEO supplementation. Conclusion The results of the present study suggested that supplementation of MEO may have limited effects on apparent
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Fan, Ao; Jaenicke, Stephan; Chuah, Gaik-Khuan
2011-10-26
A critical step in the synthesis of the rare sugars, L-lyxose and L-ribose, from the corresponding D-sugars is the oxidation to the lactone. Instead of conventional oxidizing agents like bromine or pyridinium dichromate, it was found that a heterogeneous catalyst, Pd-Bi/C, could be used for the direct oxidation with molecular oxygen. The composition of the catalyst was optimized and the best results were obtained with 5 : 1 atomic ratio of Pd : Bi. The overall yields of the five-step procedure to L-ribose and L-lyxose were 47% and 50%, respectively. The synthetic procedure is advantageous from the viewpoint of overall yield, reduced number of steps, and mild reaction conditions. Furthermore, the heterogeneous oxidation catalyst can be easily separated from the reaction mixture and reused with no loss of activity.
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[Nickel exposure to A549 cell damage and L-ascorbic acid interference effect].
Fu, Yao; Wang, Yue; Dan, Han; Zhang, Lin; Ma, Wenhan; Pan, Yulin; Wu, Yonghui
2015-05-01
Studying different concentrations of nickel smelting smoke subjects of human lung adenocarcinoma cells (A549) carcinogenic effects, discusses the influence of L-ascorbic acid protection. The A549 cells were divided into experimental and L-ascorbic acid in the intervention group. Plus exposure group concentration of nickel refining dusts were formulated 0.00, 6.25, 12.50, 25.00, 50.00, 100.00 µg/ml suspension, the intervention group on the basis of the added exposure group containing L-ascorbic acid (100 mmol/L), contact 24 h. Detection of cell viability by MTT assay. When the test substance concentration select 0.00, 25.00, 50.00, 100.00 µg/ml experiment for internal Flou-3 fluorescent probe to detect cell Ca²⁺ concentration, within DCFH-DA detect intracellular reactive oxygen (ROS) content, real-time quantitative PCR (real time, in the RT-PCR) was used to detect cell HIF-1α gene expression. With the increase of concentration, subjects increased cell growth inhibition rate, intracellular Ca²⁺ concentration increases, ROS content increased, HIF-1α gene expression increased, differences were statistically significant (P nickel exposure damage to cells. With subjects following exposure to nickel concentration increased, its effect on A549 cell damage increases, L-ascorbic acid cell damage caused by nickel has certain protective effect.
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Antioxidant and toxicological evaluation of a Tamarindus indica L. leaf fluid extract.
Escalona-Arranz, J C; Perez-Rosés, R; Rodríguez-Amado, J; Morris-Quevedo, H J; Mwasi, L B; Cabrera-Sotomayor, O; Machado-García, R; Fong-Lórez, O; Alfonso-Castillo, A; Puente-Zapata, E
2016-01-01
In the scientific community, there is a growing interest in Tamarindus indica L. leaves, both as a valuable nutrient and as a functional food. This paper focuses on exploring its safety and antioxidant properties. A tamarind leaf fluid extract (TFE) wholly characterised was evaluated for its anti-DPPH activity (IC50 = 44.36 μg/mL) and its reducing power activity (IC50 = 60.87 μg/mL). TFE also exhibited a high ferrous ion-chelating capacity, with an estimated binding constant of 1.085 mol L(-1) while its influence over nitric oxide production in human leucocytes was irregular. At low concentrations, TFE stimulated NO output, but it significantly inhibited it when there was an increase in concentration. TFE was also classified as a non-toxic substance in two toxicity tests: the acute oral toxicity test and the oral mucous irritability test. Further toxicological assays are needed, although results so far suggest that TFE might become a functional dietary supplement.
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Directory of Open Access Journals (Sweden)
Gabriella Spaltro
2017-12-01
Full Text Available Duchenne muscular dystrophy (DMD is caused by abnormalities in the dystrophin gene and is clinically characterised by childhood muscle degeneration and cardiomyopathy. We produced an induced pluripotent stem cell line from a DMD patient's dermal fibroblasts by electroporation with episomal vectors containing: hL-MYC, hLIN28, hSOX2, hKLF4, hOCT3/4. The resultant DMD iPSC line (CCMi001DMD-A-3 displayed iPSC morphology, expressed pluripotency markers, possessed trilineage differentiation potential and was karyotypically normal. MLPA analyses performed on DNA extracted from CCMi001DMD-A-3 showed a deletion of exons 49 and 50 (CCMi001DMD-A-3, ∆49, ∆50.
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Energy Technology Data Exchange (ETDEWEB)
Darriulai, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1965-03-01
Two sets of measurements of the {alpha}-{alpha} elastic scattering differential cross section are presented. The first set - angular distributions from 50 up to 120 MeV - shows two new resonances, 6{sup +} and 8{sup +}, at 25 and 57 MeV. Complex phase shifts are extracted from the data and a phenomenological potential is given. A description of the 3 {alpha}-particle 0{sup +} states in C{sup 12} is made with this interaction potential. The second set - excitation curves between 20 and 50 MeV - allows investigation of the Be{sup 8} level structure within this energy range - It identifies the 16.6 and 16.9 MeV states as 2{sup +}, but the rise of inelastic processes at higher energies makes further identification of spins and parities more and more difficult. (author) [French] Deux series de mesures de la section efficace differentielle de diffusion {alpha}-{alpha} sont presentees. La premiere - distributions angulaires entre 50 et 120 MeV - fait apparaitre deux nouvelles resonances, 6{sup +} et 8{sup +}, a 25 et 57 MeV d'excitation. Des dephasages complexes en sont extraits et un potentiel phenomenologique est presente. Une etude des etats 0{sup +} a parentage (3{alpha}) de {sup 12}C est faite a partir de ce potentiel. La seconde - courbes d'excitation s'etendant de 20 a 50 MeV - met en evidence la structure de {sup 8}Be dans cette region. Elle montre que les niveaux a 16,6 et 16,9 MeV sont des 2{sup +} mais l'importance des processus inelastiques rend difficile l'identification des niveaux d'excitation plus elevee. (auteur)
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Mohsen Arbabi
2017-12-01
Full Text Available Background: Trichomonas vaginalis infection is one of the most prevalent type of vaginitis in women. Considering the side effects of metronidazole and therapeutic properties of Arctium lappa L. and Satureja hortensis L. in traditional medicine, this study aimed to examine the anti-Trichomonas effects of Arctium lappa and Satureja hortensis alcoholic extracts in vitro. Materials and Methods: This experimental study was conducted on T. vaginalis isolated from 1203 persons referred to five health centers in Kashan city. Five T. vaginalis isolates were cultured in a TYI-S-33 medium and were used to study the effect of Arctium lappa and Satureja hortensis extracts. The effects of different concentrations (12.5, 25, 50, 100, 200, 400, 800 and 1000 µg/mL of plant extracts on the growth of T. vaginalis trophozoeites were studied 12, 24, and 48 h after the culture. Also, the culture media and metronidazole (0.025, 0.05, 0.1, 0.2, 0.4 µg/mL were considered as the negative and positive controls, respectively. The effects of the extracts and drug were examined by counting the number of live and dead parasites using the trypan blue staining method. Results: Results showed that the alcoholic extracts of Satureja hortensis and Arctium lappa had an inhibitory effect on the growth of T. vaginalis. The IC50 values of the alcoholic extracts of Satureja hortensis, Arctium lappa and metronidazole after 24 h were 190.8, 996.7 and 0.0326 µg/mL, respectively. Conclusion: The present study shows the in vitro anti-Trichomonas effect of Arctium lappa and Satureja hortensis extracts. The anti-Trichomonas effect of Satureja hortensis extract was higher than that of the Arctium lappa extract. Further studies are recommended to investigate the anti-Trichomonas effect of major components of these plants, especially the Satureja hortensis extract.
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Directory of Open Access Journals (Sweden)
Celestina Alflen Klahold
2006-04-01
Full Text Available Objetivando verificar o efeito do bioestimulante, Stimulate®, aplicado via semente e pulverização foliar, na cultura da soja, conduziu-se um experimento sob ambiente protegido, em vasos. O delineamento foi de blocos casualizados, com 4 repetições. Os tratamentos constaram da combinação de doses de bioestimulate, aplicadas via semente (0, 3 e 5 mL kg-1 de sementes na semeadura e via foliar (0,0; 0,075; 0,150 e 0,225 mL L-1, aos 58 dias após a emergência (DAE. Realizaram-se coletas de plantas aos 73 e 129 DAE.Para algumas das variáveis estudadas, nas doses utilizadas, houve efeito negativo na resposta à aplicação de bioestimulante, para algumas doses testadas. Respostas positivas foram verificadas para massa seca de flores, raízes, razão raiz/parte aérea, número de flores, vagens e grãos e produção por planta. Destacaram-se positivamente os tratamentos: 0,0 mL 0,5 kg-1 (AS + 0,150 mL L-1 (APF; 3,0 mL 0,5 kg-1 (AS + 0,0 mL L-1 (APF; 3,0 mL 0,5 kg-1 (AS+ 0,225 mL L-1 (APF e 5,0 mL 0,5 kg-1 (AS + 0,075 mL L-1 (APF.Aiming to verify the effect of the bioestimulant, Stimulate®, applied saw by seed and leaf pulverization, in the culture of the soybean. It behaved an experiment under greenhouse, in vases. Randomized block experimental design was used, with four repetitions. The treatments consisted of the combination of bioestimulant doses: seed application (SA (0; 3; and 5 mL kg-1 of seeds in the sowing and leaf spray (LS (0.0; 0.075; 0.150; and 0.225 mL L- 1, to the 58 days after the emergency (DAE. Collections of plants were accomplished to the 73 and 129 DAE. For some of the studied variables, in the used doses, there was negative effect in the response of the biostimulant application, for some tested doses. Positives responses were verified for flowers and roots dry mass; root/shoot relation; flowers; beans and grains number; and yield for plant. They stood out the treatments: 0,0 mL 0.5 kg-1 (SA + 0.150 mL L-1 (LS; 3.0 mL 0.5 kg
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Antiviral effects of Curcuma longa L. against dengue virus in vitro and in vivo
Ichsyani, M.; Ridhanya, A.; Risanti, M.; Desti, H.; Ceria, R.; Putri, D. H.; Sudiro, T. M.; Dewi, B. E.
2017-12-01
Dengue is the most common infective disease caused by dengue virus (DENV) and endemic diseases in tropical and subtropical areas. Until now, there is no specific antiviral for dengue infection. It is known that viral load is related to disease severity. Curcuma longa L. (turmeric) with curcumin as major active compound has been identified for its antiviral effect. This study to determine antiviral effect of C. longa extract on DENV-2 in vitro and in vivo along with its toxicity in liver and kidney of ddY mice. Antiviral activity (IC50) and toxicity (CC50) in vitro was examined on Huh7it-1 cells by focus assay and a MTT assay, respectively. To determine the selectivity index (SI), we used CC50 and IC50 value. The safe doses obtained were used for toxicity tests of liver and kidney with histopathological and biochemical observations. The C. longa extracts was given orally with dose of 0.147 mg/mL for each mice at 2 hours after injected with DENV-2 infected Huh7it-1 cells. Serum was collected from intraorbital at 6 hours and 24 hours after infection and focus assay was used to determine viral load. In this study, the acquired value of IC50 was 17,91 μg/mL whereas the value of CC50 was 85,4 μg/mL. The value of SI of C. longa was 4.8. In vivo, we found that C. longa remarkable reduced of viral load after 24 hour. Histopathological examination showed no specific abnormalities in liver and kidney. There was no significant increase in levels of SGPT, SGOT, urea, and creatinine. From this study it can be concluded that C. longa could potentially be used as antiviral against DENV with low cytotoxicity and effective inhibition.
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Directory of Open Access Journals (Sweden)
Darllen Suzanny Barbosa de Oliveira
2013-12-01
Full Text Available This study aimed to phytochemical study of the aerial parts of Petiveria alliacea L. (young branches and leaves, cytotoxicity evaluation (LC50 of leaves in relation to Artemia salina L. and antimicrobial activity, which were used strains of gram-positive bacterium: Staphylococcus aureus and gram-negative: Klebsiella pneumoniae and Escherichia coli, these submitted to the methanol crude extract (MCE of leaves, at the following concentrations: 25.50 and 100mg/mL. It was possible to identify in the young branches of P. alliacea L. the presence of organic acids, phenols and tannins in the alkaloids leaves, steroids and triterpenoids, saponins, phenols and tannins, where the activities of these metabolites match with some information alleged by the population. The leaves’ Methanol Crude Extract showed LC50=1709.77μg/mL, being nontoxic at the tested concentrations, whereas for plant extract in relation to A.salina are considered nontoxic when LC50>1000μg/mL. The antimicrobial activity of the Methanol Crude Extract of the leaves showed inhibition only for the bacteria Escherichia coli at 100mg/mL concentration, and this activity may be related to the presence of phenols and tannins in the extract. The obtained results turn the species promising in search of secondary metabolites, but there is the need of further studies to identify its main active ingredients. Palavras-chave: Mucuracaa, Phytochemical Screening, Class of Compounds. DOI: http://dx.doi.org/10.18561/2179-5746/biotaamazonia.v3n3p76-82
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Cytogenetic and identification of the nucleolus organizer region in Heliconia bihai (L. L.
Directory of Open Access Journals (Sweden)
Heloisa Rocha do Nascimento
2014-08-01
Full Text Available The genus Heliconia is not much studied and the number of existing species in this genus is still uncertain. It is known that this number relies between 150 to 250 species. In Brazil, about 40 species are native and known by many different names. The objective of this paper was to characterize morphometrically and to identify the NOR (active nucleolus organizer regions by Ag-NOR banding of chromosomes of Heliconia bihai (L L. Root meristems were submitted to blocking treatment in an amiprofos-methyl (APM solution, fixed in methanol-acetic acid solution for 24 hours, at least. The meristems were washed in distilled water and submitted to enzymatic digestion with pectinase enzyme. The slides were prepared by dissociation of the root meristem, dried in the air and also on hot plate at 50°C. Subsequently, some slides were submitted to 5% Giemsa stain for karyotype construction and to a solution of silver nitrate (AgNO3 50% for Ag-NOR banding. The species H. bihai has 2n = 22 chromosomes, 4 pairs of submetacentric chromosomes and 7 pairs of metacentric chromosomes, and graded medium to short (3.96 to 0.67 μM, with the presence of active NOR in pairs 1 and 2 and interphase cells with 2 nucleoli. These are the features of a diploid species.
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Lu, Chin-Heng; Lin, Tzu-Ping; Shen, She Huei; Huang, Yi-Hsiu; Chung, Hsiao-Jen; Kuo, Junne-Yih; Huang, William J S; Wu, Howard H H; Chang, Yen-Hwa; Lin, Alex T L; Chen, Kuang-Kuo
2017-07-01
Prostate cancer (PCa) is not commonly found in men younger than 50 years of age. However, serum prostate-specific antigen (PSA) concentration has been examined more frequently at a younger age in Asia partially due to an increased awareness of prostate cancer. The purpose of our study was to investigate the efficacy and complication of PSA-triggered transrectal ultrasonography-guided prostate (TRUSP) biopsies. We retrospectively reviewed TRUSP biopsies in young men with elevated PSA concentration in Taipei Veterans General Hospital. We reviewed the cases of patients younger than 50 years of age with elevated PSA concentration (>4.0 ng/mL), who received 12 cores TRUSP biopsies at TPEVGH from January 2008-December 2013. The age, family history, digital rectal examination (DRE) results, PSA concentration, free/total PSA ratio, total prostate volume, PSA density, lower urinary tract symptoms and complications after the procedure were reviewed. The pathologic findings of TRUSP biopsy and clinical follow-up were reviewed and analyzed according to the Epstein criteria. A total of 77 patients were included and were divided into 2 groups: 1) the younger group consisted of 20 patients <40 years of age; and 2) the elder group had 57 patients who were 40-50 years of age. The overall detection rate of PCa was 11.69% (9/77), and all of the PCa cases were diagnosed in the elder group (group detection rate: 15.8%). There was a significant difference in the severity of lower urinary tract symptoms (LUTS) between these 2 groups. All PCa patients were clinically significant according to the Epstein criteria. Two patients experienced fever (2.60%) after TRUSP biopsy. From our patient cohort, it appears that no benefit was apparent for patients younger than 40 years old who received TRUSP biopsy, even with elevated PSA. However, PCa detected in men between 40 and 50 years of age were all clinically significant. Overall, our results supported current major practice guidelines which
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Directory of Open Access Journals (Sweden)
Sanghamitra Dutta
2016-04-01
Full Text Available Antioxidants are naturally occurring substances that combat oxidative damage in biological entities. An antioxidant achieves this by slowing or preventing the oxidation process that can damage cells in the body. It does this by getting oxidized itself in place of the cells. The aim of the present study was to evaluate the in vitro antioxidant and free radical scavenging activities of aqueous and 95% methanol leaf extracts of four herbs viz. Trigonella foenum-graecum L, Murraya koenigii, Coriandrum sativum and Centella asiatica which have frequent use in Indian cuisine. Both aqueous and 95% methanol leaf extracts have shown significant amount reducing power. Both aqueous and 95% methanol leaf extracts of Coriandrum sativum had significant DPPH radical scavenging activity with IC50 value of 0.21± 0.3 mg/L and 0.176 ± 0.008 mg/L respectively. The aqueous leaf extract of Trigonella foenum-graecum L showed low scavenging activity. Among all the leaf extracts, the aqueous leaf extract of Centella asiatica has exhibited significantly high NO radical scavenging activity (80% with IC50 value of 0.11 ± 0.17 mg/L. The aqueous leaf extracts of the samples have showed significantly high superoxide radical scavenging activity. The activity was maximum for the aqueous leaf extract of Centella asiatica, IC50 value is 4.36 ± 0.41 mg/L. anti lipid peroxide activities were very high ( 90 % for aqueous leaf extracts of Coriandrum sativum (IC50 = 0.064 ± 0.85 mg/L and Centella asiatica (IC50 = 0.066 ± 0.9mg/L at a concentration of 0.16 mg/L. The aqueous leaf extracts of the samples were found to contain large amounts of flavonoids and phenolic compounds and exhibited high antioxidant and free radical scavenging activities. These in vitro assays indicate that these plant extracts are significant source of natural antioxidants which might be helpful in preventing the progress of various oxidative stresses.
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Yang, Zhongzhou; Chen, Jing; Dou, Runzhi; Gao, Xiang; Mao, Chuanbin; Wang, Li
2015-11-30
In this study, the phytotoxicity of seven metal oxide nanoparticles(NPs)-titanium dioxide (nTiO₂), silicon dioxide (nSiO₂), cerium dioxide (nCeO₂), magnetite (nFe₃O₄), aluminum oxide (nAl₂O₃), zinc oxide (nZnO) and copper oxide (nCuO)-was assessed on two agriculturally significant crop plants (maize and rice). The results showed that seed germination was not affected by any of the seven metal oxide NPs. However, at the concentration of 2000 mg·L(-1), the root elongation was significantly inhibited by nCuO (95.73% for maize and 97.28% for rice), nZnO (50.45% for maize and 66.75% for rice). On the contrary, minor phytotoxicity of nAl₂O₃ was only observed in maize, and no obvious toxic effects were found in the other four metal oxide NPs. By further study we found that the phytotoxic effects of nZnO, nAl₂O₃ and nCuO (25 to 2000 mg·L(-)¹) were concentration dependent, and were not caused by the corresponding Cu(2+), Zn(2+) and Al(3+) ions (0.11 mg·L(-)¹, 1.27 mg·L(-)¹ and 0.74 mg·L(-)¹, respectively). Furthermore, ZnO NPs (<50 nm) showed greater toxicity than ZnO microparticles(MPs)(<5 μm) to root elongation of both maize and rice. Overall, this study provided valuable information for the application of engineered NPs in agriculture and the assessment of the potential environmental risks.
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Williams, John Russell; Rayburn, James R; Cline, George R; Sauterer, Roger; Friedman, Mendel
2014-08-06
The embryo toxicities of two food-processing-induced toxic compounds, acrylamide and furan, with and without added L-cysteine were examined individually and in mixtures using the frog embryo teratogenesis assay-Xenopus (FETAX). The following measures of developmental toxicity were used: (a) 96 h LC50, the median concentration causing 50% embryo lethality; (b) 96 h EC50, the median concentration causing 50% malformations of the surviving embryos; and (c) teratogenic index (96 h LC50/96 h EC50), an estimate of teratogenic risk. Calculations of toxic units (TU) were used to assess possible antagonism, synergism, or response addition of several mixtures. The evaluated compounds demonstrated counterintuitive effects. Furan had lower than expected toxicity in Xenopus embryos and, unlike acrylamide, does not seem to be teratogenic. However, the short duration of the tests may not show the full effects of furan if it is truly primarily genotoxic and carcinogenic. L-Cysteine showed unexpected properties in the delay of hatching of the embryos. The results from the interaction studies between combination of two or three components (acrylamide plus L-cysteine; furan plus L-cysteine; acrylamide plus furan; acrylamide plus furan and L-cysteine) show that furan and acrylamide seem to have less than response addition at 1:1 toxic unit ratio in lethality. Acrylamide and L-cysteine show severe antagonism even at low 19 acrylamide/1 L-cysteine TU ratios. Data from the mixture of acrylamide, furan, and L-cysteine show a slight antagonism, less than would have been expected from binary mixture exposures. Bioalkylation mechanisms and their prevention are discussed. There is a need to study the toxicological properties of mixtures of acrylamide and furan concurrently formed in heat-processed food.
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Bayoub, Kaoutar; Mardad, Ilham; Ammar, Emna; Serrano, Aurelio; Soukri, Abdelaziz
2011-02-01
Strain 3D, isolated from fermented traditional Moroccan dairy product, and identified as Enterococcus faecium, was studied for its capability to produce two bacteriocins acting against Listeria monocytogenes. Bacteriocins 3 Da and 3Db were heat stable inactivated by proteinase K, pepsin, and trypsin but not when treated with catalase. The evidenced bacteriocins were stable in a wide pH range from 2 to 11 and bactericidal activity was kept during storage at 4°C. However, the combination of temperature and pH exhibited a stability of the bacteriocins. RP-HPLC purification of the anti-microbial compounds shows two active fractions eluted at 16 and 30.5 min, respectively. Mass spectrometry analysis showed that E. faecium 3D produce two bacteriocins Enterocin 3 Da (3893.080 Da) and Enterocin 3Db (4203.350 Da). This strain is food-grade organism and its bacteriocins were heat-stable peptides at basic, neutral, and acid pH: such bacteriocins may be of interest as food preservatives.
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Operating experience with the IMPELA-10/50 industrial linac
International Nuclear Information System (INIS)
Ungrin, J.; Alexander, S.B.; Craig, S.T.; Frketich, G.; Mason, V.A.; McIntyre, I.L.; Simpson, M.P.; Smyth, D.L.; West, R.J.; White, B.F.
1991-01-01
AECL is building and marketing the IMPELA family of high-power linear electron accelerators designed specifically for the industrial market. The accelerators are built around an L-band on-axis coupled structure that is assembled in a modular fashion and is driven in the long-pulse mode with a modulating anode klystron. A wide range of average power is achieved with the same basic accelerator components by simply changing the beam duty factor and the size of the power supply. The control system for the IMPELA family is built around a simplified operator interface that incorporates automatic sequences, fast control loops, self-diagnostics and the instrumentation that is key to reliable, simple operation and rapid maintenance. The first member of the IMPELA family, the 10 MeV, 50 kW, IMPELA-10/50, is a highly instrumented industrial prototype that has been operating at fun power since 1989 November. It is now undergoing prolonged testing at Chalk River Laboratories
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Event reporting guidelines 10 CFR 50.72 and 50.73. Revision 1
Energy Technology Data Exchange (ETDEWEB)
Allison, D P; Harper, M R; Jones, W R; MacKinnon, J B; Sandin, S S
1998-01-01
Revision 1 to NUREG-1022 clarifies the immediate notification requirements of Title 10 of the Code of Federal Regulations, Part 50, Section 50.72 (10 CFR 50.72), and the 30-day written licensee event report (LER) requirements of 10 CFR 50.73 for nuclear power plants. This revision was initiated to improve the reporting guidelines related to 10 CFR 50.72 and 50.73 and to consolidate these guidelines into a single reference document. A first draft of this document was noticed for public comment in the Federal Register on october 7, 1991 (56 FR 50598). A second draft was noticed for comment in the Federal Register on February 7, 1994 (59 FR 5614). This document updates and supersedes NUREG-1022 and its Supplements 1 and 2 (published in September 1983, February 1984, and September 1985, respectively). It does not change the reporting requirements of 10 CFR 50.72 and 50.73.
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Event reporting guidelines 10 CFR 50.72 and 50.73. Revision 1
International Nuclear Information System (INIS)
Allison, D.P.; Harper, M.R.; Jones, W.R.; MacKinnon, J.B.; Sandin, S.S.
1998-01-01
Revision 1 to NUREG-1022 clarifies the immediate notification requirements of Title 10 of the Code of Federal Regulations, Part 50, Section 50.72 (10 CFR 50.72), and the 30-day written licensee event report (LER) requirements of 10 CFR 50.73 for nuclear power plants. This revision was initiated to improve the reporting guidelines related to 10 CFR 50.72 and 50.73 and to consolidate these guidelines into a single reference document. A first draft of this document was noticed for public comment in the Federal Register on october 7, 1991 (56 FR 50598). A second draft was noticed for comment in the Federal Register on February 7, 1994 (59 FR 5614). This document updates and supersedes NUREG-1022 and its Supplements 1 and 2 (published in September 1983, February 1984, and September 1985, respectively). It does not change the reporting requirements of 10 CFR 50.72 and 50.73
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Directory of Open Access Journals (Sweden)
Luiz Marivando Barros
2016-02-01
Full Text Available Drug resistance in the treatment of neglected parasitic diseases, such as leishmaniasis and trypanosomiasis, has led to the search and development of alternative drugs from plant origins. In this context, the essential oil extracted by hydro-distillation from Lantana camara leaves was tested against Leishmania braziliensis and Trypanosoma cruzi. The results demonstrated that L. camara essential oil inhibited T. cruzi and L. braziliensis with IC50 of 201.94 μg/mL and 72.31 μg/mL, respectively. L. camara essential oil was found to be toxic to NCTC929 fibroblasts at 500 μg/mL (IC50 = 301.42 μg/mL. The composition of L. camara essential oil analyzed by gas chromatography–mass spectrometry (GC/MS revealed large amounts of (E-caryophyllene (23.75%, biciclogermacrene (15.80%, germacrene D (11.73%, terpinolene (6.1%, and sabinene (5.92%, which might be, at least in part, responsible for its activity. Taken together, our results suggest that L. camara essential oil may be an important source of therapeutic agents for the development of alternative drugs against parasitic diseases.
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Subcutaneous L-tyrosine elicits cutaneous analgesia in response to local skin pinprick in rats.
Hung, Ching-Hsia; Chiu, Chong-Chi; Liu, Kuo-Sheng; Chen, Yu-Wen; Wang, Jhi-Joung
2015-10-15
The purpose of the study was to estimate the ability of L-tyrosine to induce cutaneous analgesia and to investigate the interaction between L-tyrosine and the local anesthetic lidocaine. After subcutaneously injecting the rats with L-tyrosine and lidocaine in a dose-dependent manner, cutaneous analgesia (by blocking the cutaneous trunci muscle reflex-CTMR) was evaluated in response to the local pinprick. The drug-drug interaction was analyzed by using an isobolographic method. We showed that both L-tyrosine and lidocaine produced dose-dependent cutaneous analgesia. On the 50% effective dose (ED50) basis, the rank of drug potency was lidocaine (5.09 [4.88-5.38] μmol)>L-tyrosine (39.1 [36.5-41.8] μmol) (Ptyrosine lasted longer than that caused by lidocaine (Ptyrosine exhibited an additive effect on infiltrative cutaneous analgesia. Our pre-clinical study demonstrated that L-tyrosine elicits the local/cutaneous analgesia, and the interaction between L-tyrosine and lidocaine is additive. L-tyrosine has a lower potency but much greater duration of cutaneous analgesia than lidocaine. Adding L-tyrosine to lidocaine preparations showed greater duration of cutaneous analgesia compared with lidocaine alone. Copyright © 2015 Elsevier B.V. All rights reserved.
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Directory of Open Access Journals (Sweden)
Murilo Fazolin
2007-02-01
Full Text Available Óleos essenciais das piperáceas Piper aduncum L., Piper hispidinervum C. DC. e da bignoniácea Tanaecium nocturnum (Barb. Rodr. Bur. & K. Shum foram avaliados para o controle de larvas de Tenebrio molitor L., 1758. Para a avaliação do efeito por contato em superfície contaminada, foram utilizados papéis-filtro impregnados com diferentes quantidades dos óleos essenciais. Para a avaliação do efeito tópico foram aplicados 5 mL de soluções com diferentes concentrações dos óleos sobre larvas de quinto instar do inseto. A taxa de mortalidade foi a variável utilizada para avaliar os experimentos. Todos os óleos essenciais apresentaram efeito inseticida sobre larvas de T. molitor, sendo que as respostas variaram em função da concentração utilizada, assim como do método de exposição do inseto. A toxicidade dos óleos essenciais foi elevada apresentando os seguintes valores de CL50: 0,045; 0,033 e 1,515 mL de óleo cm-2 para exposição por contato (papel filtro aos óleos de P. hispidinervum,P. aduncum e T. nocturnum, respectivamente. Para a aplicação tópica, os valores da DL50 foram de: 0,000025; 0,009 e 0,000015 mL de óleo mg de inseto -1 para os óleos essenciais de P. hispidinervum,P. aduncum e T. nocturnum, respectivamente. Resultados promissores para o emprego desses óleos essenciais como inseticidas foram obtidos utilizando-se concentrações acima de 3,0% (v v-1 para P. hispidinervum e 2,5% (v v-1 para P. aduncum e T. nocturnum.Essential oils from Piper aduncum L., Piper hispidinervum C. DC. (Piperaceae and Tanaecium nocturnum (Barb. Rodr. Bur.& K. Shum (Bignoniaceae were tested against Tenebrio molitor L., 1758 larvaes. Filter paper with different amounts of oils were employed for contact toxicity effects study. For topical effect study, aliquots of 5 mL of oils at different concentrations were applied on larvaes of the fifth instar. Mortality rate was used to evaluate the assays. All essential oils possessed
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Directory of Open Access Journals (Sweden)
Zhi Long Liu
2013-09-01
Full Text Available The aim of this research was to determine the chemical composition and insecticidal and repellent activity of the essential oil of Artemisia rupestris L. aerial parts against the booklice Liposcelis bostrychophila Badonnel and isolation of insecticidal and repellent constituents from the essential oil. The essential oil of A. rupestris was obtained by hydrodistillation and analyzed by GC-MS. A total of 30 components of the essential oil of A. rupestris was identified and the principal compounds in the essential oil were α-terpinyl acetate (37.18%, spathulenol (10.65%, α-terpineol (10.09%, and linalool (7.56%, followed by 4-terpineol (3.92% and patchoulol (3.05%. Based on bioactivity-guided fractionation, the four active constituents were isolated from the essential oil and identified as α-terpineol, α-terpinyl acetate, 4-terpineol and linalool. The essential oil of A. rupestris exhibited contact toxicity against L. bostrychophila with LD50 value of 414.48 µg/cm2. α-Terpinyl acetate (LD50 = 92.59 µg/cm2 exhibited stronger contact toxicity against booklice than α-terpineol (LD50 = 140.30 µg/cm2, 4-terpineol (LD50 = 211.35 µg/cm2, and linalool (LD50 = 393.16 µg/cm2. The essential oil of A. rupestris (LC50 = 6.67 mg/L air also possessed fumigant toxicity against L. bostrychophila while the four constituents, 4-terpineol, α-terpineol, α-terpinyl acetate and linalool had LC50 values of 0.34, 1.12, 1.26 and 1.96 mg/L air, respectively. α-Terpinol and α-terpinyl acetate showed strong repellency against L. bostrychophila, while linalool and 4-terpinol exhibited weak repellency. The results indicate that the essential oil of A. rupestris aerial parts and its constituent compounds have potential for development into natural insecticides or fumigants as well as repellents for control of insects in stored grains.
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Effects of salt stress levels on five maize ( Zea mays L.) cultivars at ...
African Journals Online (AJOL)
Effects of salt stress levels on five maize ( Zea mays L.) cultivars at germination stage. ... To investigation the effects of salt stress levels (0, 50, 100, 150, 200 and 250 mM NaCl) on five maize (Zea mays L.) cultivars at ... from 32 Countries:.
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Directory of Open Access Journals (Sweden)
Heni Purwitasari
2017-03-01
Full Text Available Cocor Bebek (Kalanchoe pinnata L. is a medicinal plant that has been used as traditional medicine for long period, used to fight fever, but it empirically leaves of Tembelekan (Lantana camara L. are also generally primarily used to treat fever. Research on the effects of the combination of Cocor Bebek’s leaf extract (Kalanchoe pinnata L. and the leaf extract of tembelekan (Lantana camara L. Pers on male guinea pig (Cavia porcellus is induced peptone 5% at a dose of 150 mg / kg body weight. With the aim to determine the effect of the combination and determine the effects of the most effective as an antipyretic. Extracts prepared by maceration method using ethanol 95%. Marmots were divided into 4 groups. Each guinea pig was induced using peptone 5%. The first group was given Na CMC as a negative control group 2nd given a combination of one dose combinations (50 + 720. Group 3 was given a second dose combination (100 + 720. Group-4 were given a 3-dose combination (150 + 720. Temperature measurement is carried out for 2 hours with a 30 minute interval. Data were analyzed temperature measurements were statistically analyzed using ANOVA (Analisys Of Variance. The research result was addressing, that the combination of extracts can reduce fever. The combination is most effective as an antipyretic is cocor duck leaf extract 50 mg and 720 mg tembelekan leaf extract (50 + 720.
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AUTOMATISATION ET CONTROLE A DISTANCE DE L'INSTRUMENTATION DU LASER R.I.L.I.S. A ISOLDE
Chevallay, E
2003-01-01
A Isolde, les physiciens utilisent pour leurs expériences des isotopes rares produits par l'interaction d'un faisceau de protons provenant du synchrotron Booster et d'une cible métallique. Derrière cette cible, les isotopes qui sont produits et accélérés ne sont pas tous du même type et de la même masse. Des aimants de spectromètres (GPS ou HRS) sélectionnent les isotopes requis en fonction du rapport masse/charge. De plus, l'utilisation d'un laser de puissance pour ioniser les isotopes, le laser R.I.L.I.S. (Résonance Ionization Laser Ion Source), permet une bien meilleure sélectivité. Le système de lasers RILIS a été construit par la collaboration Isolde [1] en 1990. Son implication dans le programme de physique d'Isolde représente 50 % des expériences approuvées. Etant l'un des éléments clefs de la production d'isotopes rares à Isolde, il a bien entendu été intégré dans le programme de consolidation lancé en 2000 [2]. La consolidation du laser lui-même n'entre pas dans le cadre d...
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Shaymurat, Talgar; Gu, Jianxiu; Xu, Changshan; Yang, Zhikun; Zhao, Qing; Liu, Yuxue; Liu, Yichun
2012-05-01
The effects of zinc oxide nanoparticles (ZnO NPs) on the root growth, root apical meristem mitosis and mitotic aberrations of garlic (Allium sativum L.) were investigated. ZnO NPs caused a concentration-dependent inhibition of root length. When treated with 50 mg/L ZnO NPs for 24 h, the root growth of garlic was completely blocked. The 50% inhibitory concentration (IC(50)) was estimated to be 15 mg/L. The mitosis index was also decreased in a concentration- and time-dependent manner. ZnO NPs also induced several kinds of mitotic aberrations, mainly consisted of chromosome stickiness, bridges, breakages and laggings. The total percentage of abnormal cells increased with the increase of ZnO NPs concentration and the prolongation of treatment time. The investigation provided new information for the possible genotoxic effects of ZnO NPs on plants.
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Gastroprotective activity of the chloroform extract of the roots from Arctium lappa L.
Dos Santos, Ana C; Baggio, Cristiane H; Freitas, Cristina S; Lepieszynski, Juliana; Mayer, Bárbara; Twardowschy, André; Missau, Fabiana C; dos Santos, Elide P; Pizzolatti, Moacir G; Marques, Maria C A
2008-06-01
Arctium lappa L. is used in folk medicine as a diuretic, depurative and digestive stimulant and in dermatological conditions. The objective of this study was to evaluate the effect and the possible mechanisms involved in the gastroprotective effects of a chloroform extract (CE) of the roots from A. lappa and its fractions. Oral pretreatment with CE (10, 30 and 100 mg kg(-1)) significantly reduced gastric lesions induced by ethanol by 61%, 70% and 76%, respectively. Oral administration of CE (100 mg kg(-1) per day for 7 days) reduced the chronic gastric ulceration induced by acetic acid by 52%. Intraduodenal CE (100, 300 and 600 mg kg(-1)) reduced the total acidity of gastric secretion by 22%, 22% and 33%, respectively, while i.p. administration (10, 30 and 100 mg kg(-1)) inhibited total acidity by 50%, 60% and 67%, respectively. In-vitro, CE inhibited H+, K+ -ATPase activity with an EC50 of 53 microgmL(-1) and fraction A (30 and 100 microgmL(-1)) reduced this by 48% and 89%, respectively. CE had no effect on gastrointestinal motility. CE (250 microgmL(-1)) and fraction B (100 and 250 microgmL(-1)) had free-radical scavenging ability, inhibiting 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical activity by 50%, 20% and 55%, respectively. Collectively, the results show that the CE protects animals from gastric lesions by reducing gastric acid secretion via inhibition of gastric H+, K+ -ATPase.
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Majandusorganisatsioon OECD soovitab eakaid kauem tööl hoida / Aleksei Günter
Günter, Aleksei, 1979-
2005-01-01
Majanduskoostöö ja Arengu Organisatsiooni OECD poolt läbi viidud uuringu tulemused näitavad, et organisatsiooni liikmesriikides käib tööl vähem kui 60 protsenti 50-64-aastastest inimestest, olukorra põhjustena toob organisatsioon esile riikide tööturupoliitika ja tööandjate hoiakud. Diagramm: Kui vanalt käiakse veel tööl?
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Reyes, Andres; Messina, Carlos D; Hammer, Graeme L; Liu, Lu; van Oosterom, Erik; Lafitte, Renee; Cooper, Mark
2015-12-01
Breeders have successfully improved maize (Zea mays L.) grain yield for the conditions of the US corn-belt over the past 80 years, with the past 50 years utilizing single-cross hybrids. Long-term improvement for grain yield under water-limited conditions has also been reported. Grain yield under water-limited conditions depends on water use, water use efficiency, and harvest index. It has been hypothesized that long-term genetic gain for yield could be due, in part, to increased water capture from the soil. This hypothesis was tested using a set of elite single-cross hybrids that were released by DuPont Pioneer between 1963 and 2009. Eighteen hybrids were grown in the field during 2010 and 2011 growing seasons at Woodland, CA, USA. Crops grew predominantly on stored soil water and drought stress increased as the season progressed. Soil water content was measured to 300cm depth throughout the growing season. Significant water extraction occurred to a depth of 240-300cm and seasonal water use was calculated from the change in soil water over this rooting zone. Grain yield increased significantly with year of commercialization, but no such trend was observed for total water extraction. Therefore, the measured genetic gain for yield for the period represented by this set of hybrids must be related to either increased efficiency of water use or increased carbon partitioning to the grain, rather than increased soil water uptake. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.
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Thirteen week toxicity study of dietary l-tryptophan in rats with a recovery period of 5 weeks.
Shibui, Yusuke; Matsumoto, Hideki; Masuzawa, Yoko; Ohishi, Takumi; Fukuwatari, Tsutomu; Shibata, Katsumi; Sakai, Ryosei
2018-04-01
Although l-tryptophan is nutritionally important and widely used in medical applications, toxicity data for its oral administration are limited. The purpose of this study was to evaluate the potential toxicity of an experimental diet containing added l-tryptophan at doses of 0 (basal diet), 1.25%, 2.5% and 5.0% when administered to Sprague-Dawley rats for 13 weeks. There were no toxicological changes in clinical signs, ophthalmology, urinalysis, hematology, necropsy, organ weight and histopathology between control rats and those fed additional l-tryptophan. Body weight gain and food consumption significantly decreased throughout the administration period in males in the 2.5% group and in both sexes in the 5.0% group. At the end of the dosing period, decreases in water intake in males in the 5.0% group and in serum glucose in females in the 5.0% group were observed. The changes described above were considered toxicologically significant; however, they were not observed after a 5 week recovery period, suggesting reversibility. Consequently, the no-observed-adverse-effect level of l-tryptophan in the present study was 1.25% for males and 2.5% for females (mean intake of l-tryptophan: 779 mg kg -1 body weight day -1 [males] and 1765 mg kg -1 body weight day -1 [females]). As the basal diet used in this study contained 0.27% of proteinaceous l-tryptophan, the no-observed-adverse-effect level of overall l-tryptophan was 1.52% for males and 2.77% for females (mean intake of overall l-tryptophan: 948 mg kg -1 body weight day -1 (males) and 1956 mg kg -1 body weight day -1 (females)). We conclude that l-tryptophan has a low toxicity profile in terms of human use. Copyright © 2017 John Wiley & Sons, Ltd.
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de Jesus, Daiane; Figueira, Leandro Wagner; de Oliveira, Felipe Eduardo; Pacheco Soares, Cristina; Camargo, Samira Estves Afonso; Jorge, Antonio Olavo Cardoso; de Oliveira, Luciane Dias
2017-01-01
R. officinalis L. is an aromatic plant commonly used as condiment and for medicinal purposes. Biological activities of its extract were evaluated in this study, as antimicrobial effect on mono- and polymicrobial biofilms, cytotoxicity, anti-inflammatory capacity, and genotoxicity. Monomicrobial biofilms of Candida albicans, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans and Pseudomonas aeruginosa and polymicrobial biofilms composed of C. albicans with each bacterium were formed in microplates during 48 h and exposed for 5 min to R. officinalis L. extract (200 mg/mL). Its cytotoxic effect was examined on murine macrophages (RAW 264.7), human gingival fibroblasts (FMM-1), human breast carcinoma cells (MCF-7), and cervical carcinoma cells (HeLa) after exposure to different concentrations of the extract, analyzed by MTT, neutral red (NR), and crystal violet (CV) assays. The anti-inflammatory activity was evaluated on RAW 264.7 non-stimulated or stimulated by lipopolysaccharide (LPS) from Escherichia coli and treated with different concentrations of the extract for 24 h. Interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) were quantified by ELISA. Genotoxicity was verified by the frequency of micronuclei (MN) at 1000 cells after exposure to concentrations of the extract for 24 h. Data were analyzed by T-Test or ANOVA and Tukey Test (P ≤ 0.05). Thus, significant reductions in colony forming units per milliliter (CFU/mL) were observed in all biofilms. Regarding the cells, it was observed that concentrations ≤ 50 mg/mL provided cell viability of above 50%. Production of proinflammatory cytokines in the treated groups was similar or lower compared to the control group. The MN frequency in the groups exposed to extract was similar or less than the untreated group. It was shown that R. officinalis L. extract was effective on mono- and polymicrobial biofilms; it also provided cell viability of above 50% (at
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Khalkhali, Soodabeh; Mojgani, Naheed
2017-01-01
Background and Objectives: Human milk is a continuous supply of Lactic Acid bacteria (LAB), including enterococci with probiotic potentials. The aim of this study was to analyze two Enterococcus species, isolated from human milk for their probiotic potential, bacteriocin producing ability and virulence traits. Materials and Methods: Enterococcus faecium TA0033 and E. faecalis TA102 were tested for acid and bile tolerance, survival in simulated gastric and intestinal conditions. The antibacterial spectrum of the isolates was tested by agar well diffusion assay. The antagonistic agent was characterized by physico-chemical methods. The enterocin structural genes, virulence determinants, vancomycin resistance and biogenic amine genes, such as hdc1, hdc2, tdc, ldc and odc were also determined. Results: The tested isolates survived acidic conditions, high bile salt (1%), simulated gastric and intestinal conditions. The culture supernatant fluids of the two isolates inhibited the growth of Escherichia coli, Listeria monocytogenes, Salmonella typhi, Staphylococcus aureus, Shigella dysenteriae and Streptococcus agalactiae. The antagonistic activity was lost in the presence of proteolytic enzymes but tolerated the action of catalase, lysozyme and lipase. In contrast to enterocin TA102, enterocin TA0033 possessed bactericidal mode of action. Bacteriocin structural genes, entA and entB were present in the genome of the two isolates, while E. faecalis TA102 additionally harboured entP and bac31 genes. The phenotypic and genotypic virulence assessment studies indicated hyaluronidase (hyl) production and vancomycin resistance in E. faecalis TA102 while, none of the isolates harboured the biogenic amine genes. Conclusion: The presence of virulence genes in E. faecalis TA102 calls for careful monitoring of Enterococcus isolates for their safety parameters. PMID:29238458
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L-leucine methyl ester stimulates insulin secretion and islet glutamate dehydrogenase
DEFF Research Database (Denmark)
Knudsen, P; Kofod, Hans; Lernmark, A
1983-01-01
Column perifusion of collagenase-isolated mouse pancreatic islets was used to study the dynamics of insulin release in experiments lasting for several hours. The methyl esters of L-leucine and L-arginine were synthesized. Whereas L-arginine methyl ester (L-arginine OMe) had no effect, L-leucine OMe...... stimulated the release of insulin. The effect of L-leucine OMe was maximal at 5 mmol/liter. Whereas the Km for glucose-stimulated insulin release was unaffected by 1 mmol/liter L-leucine OMe, the maximal release of D-glucose was increased by the amino acid derivative that appeared more effective than L......-leucine. L-Leucine OMe was also a potent stimulus of insulin release from the perfused mouse pancreas. In the presence of 10 mmol/liter L-glutamine, 1 mmol/liter L-leucine OMe induced a 50- to 75-fold increase in insulin release. A similar stimulatory effect was also observed in column-perifused RIN 5F cells...
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Goldsmith, Chloe D; Vuong, Quan V; Sadeqzadeh, Elham; Stathopoulos, Costas E; Roach, Paul D; Scarlett, Christopher J
2015-07-17
Olea europaea L. leaves are an agricultural waste product with a high concentration of phenolic compounds; especially oleuropein. Oleuropein has been shown to exhibit anti-proliferative activity against a number of cancer types. However, they have not been tested against pancreatic cancer, the fifth leading cause of cancer related death in Western countries. Therefore, water, 50% ethanol and 50% methanol extracts of Corregiola and Frantoio variety Olea europaea L. leaves were investigated for their total phenolic compounds, total flavonoids and oleuropein content, antioxidant capacity and anti-proliferative activity against MiaPaCa-2 pancreatic cancer cells. The extracts only had slight differences in their phytochemical properties, and at 100 and 200 μg/mL, all decreased the viability of the pancreatic cancer cells relative to controls. At 50 μg/mL, the water extract from the Corregiola leaves exhibited the highest anti-proliferative activity with the effect possibly due to early eluting HPLC peaks. For this reason, olive leaf extracts warrant further investigation into their potential anti-pancreatic cancer benefits.
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Energy Technology Data Exchange (ETDEWEB)
Martinelli, A., E-mail: alberto.martinelli@spin.cnr.it [SPIN-CNR, C.so Perrone 24, 16152 Genova (Italy); Ferretti, M. [SPIN-CNR, C.so Perrone 24, 16152 Genova (Italy); Universita degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, 16146 Genova (Italy); Cimberle, M.R. [IMEM-CNR, Via Dodecaneso 33, 16146, Genova (Italy); Ritter, C. [Institute Laue-Langevin, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9 (France)
2012-12-15
The crystal and magnetic structures of (Tm{sub 0.50}Ca{sub 0.50})MnO{sub 3} and (Lu{sub 0.50}Ca{sub 0.50})MnO{sub 3} have been investigated between 5 K and 300 K by means of high resolution neutron powder diffraction followed by Rietveld refinement and dc magnetic measurements. During cooling orbital ordering at the Mn sub-lattice takes place at T{sub OO}{approx}280 K in both compounds, inducing an orthorhombic to monoclinic phase transition. As the temperature is further decreased an antiferromagnetic CE-type structure occurs in both compounds at T{sub N}{approx}105 K. The comparison with other (Ln{sub 0.50}Ca{sub 0.50})MnO{sub 3} compounds reveals that at room temperature the average Jahn-Teller distortion increases sharply with the decrease of the ionic radius for lanthanides heavier than Sm. The ordered magnetic moment progressively decreases as the lanthanide ionic radius decreases on account of the decreased values of the Mn-O-Mn bond angles. - Graphical abstract: Rietveld refinement plot for (Tm{sub 0.50}Ca{sub 0.50})MnO{sub 3} obtained from neutron powder diffraction data collected at 5 K; the inset shows the CE-type spin ordering taking place at the Mn sub-lattice. Highlights: Black-Right-Pointing-Pointer The crystal and magnetic structures of (Tm{sub 0.50}Ca{sub 0.50})MnO{sub 3} and (Lu{sub 0.50}Ca{sub 0.50})MnO{sub 3} were analyzed by neutron powder diffraction. Black-Right-Pointing-Pointer Orbital ordering takes place below T{sub OO}{approx}280 K in both compounds. Black-Right-Pointing-Pointer An antiferromagnetic CE-type structure occurs in both compounds below T{sub N}{approx}105 K. Black-Right-Pointing-Pointer A Comparison with other (Ln{sub 0.50}Ca{sub 0.50})MnO{sub 3} compounds is reported.
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Taira, Norihisa; Katsuyama, Yushi; Yoshioka, Masato; Muraoka, Osamu; Morikawa, Toshio
2018-04-10
l-Ascorbic acid has multifunctional benefits on skin aesthetics, including inhibition of melanin production, and is widely used in cosmetics. It, however, has low stability and poor skin penetration. We hypothesize that alkylglyceryl-l-ascorbic acid derivatives, highly stable vitamin C-alkylglycerol conjugates, would have similar anti-melanogenic activity with better stability and penetration. We test 28 alkylglyceryl-l-ascorbic acid derivatives ( 1 - 28 ) on theophylline-stimulated B16 melanoma 4A5 cells to determine if they inhibit melanogenesis and establish any structure-function relationships. Although not the most potent inhibitors, 3- O -(2,3-dihydroxypropyl)-2- O -hexyl-l-ascorbic acid ( 6 , IC 50 = 81.4 µM) and 2- O -(2,3-dihydroxypropyl)-3- O -hexyl-l-ascorbic acid ( 20 , IC 50 = 117 µM) are deemed the best candidate derivatives based on their inhibitory activities and low toxicities. These derivatives are also found to be more stable than l-ascorbic acid and to have favorable characteristics for skin penetration. The following structural requirements for inhibitory activity of alkylglyceryl-l-ascorbic acid derivatives are also determined: (i) alkylation of glyceryl-l-ascorbic acid is essential for inhibitory activity; (ii) the 3- O -alkyl-derivatives ( 2 - 14 ) exhibit stronger inhibitory activity than the corresponding 2- O -alkyl-derivatives ( 16 - 28 ); and (iii) derivatives with longer alkyl chains have stronger inhibitory activities. Mechanistically, our studies suggest that l-ascorbic acid derivatives exert their effects by suppressing the mRNA expression of tyrosinase and tyrosine-related protein-1.
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Anti-Trypanosoma cruzi and cytotoxic activities of Eugenia uniflora L.
Santos, Karla K A; Matias, Edinardo F F; Tintino, Saulo R; Souza, Celestina E S; Braga, Maria F B M; Guedes, Gláucia M M; Rolón, Miriam; Vega, Celeste; de Arias, Antonieta Rojas; Costa, José G M; Menezes, Irwin R A; Coutinho, Henrique D M
2012-05-01
Chagas disease is caused by Trypanosoma cruzi, being considered a public health problem. An alternative to combat this pathogen is the use of natural products isolated from fruits such as Eugenia uniflora, a plant used by traditional communities as food and medicine due to its antimicrobial and biological activities. Ethanolic extract from E. uniflora was used to evaluate in vitro anti-epimastigote and cytotoxic activity. This is the first record of anti-Trypanosoma activity of E. uniflora, demonstrating that a concentration presenting 50% of activity (EC(50)) was 62.76 μg/mL. Minimum inhibitory concentration (MIC) was ≤ 1024 μg/mL. Our results indicate that E. uniflora could be a source of plant-derived natural products with anti-epimastigote activity with low toxicity. Copyright © 2012 Elsevier Inc. All rights reserved.
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Irradiation sensibility of different provenances of Jatropha curcas L. seeds
International Nuclear Information System (INIS)
Yang Qing; Xu Congheng; Peng Daiping; Duan Zhubiao; Han Lei; Sun Qixiang; Peng Zhenhua
2007-01-01
The irradiation sensibility of 10 provenances of Jatropha curcas L. seeds to 60 Co γ-rays was studied. The results showed that the relationship between relative germination rate of the seeds and the doses of irradiation was negative correlation, and the difference of relative germination rate among different doses treatment was significant at 5% probability level or highly significant at 1% probability level. For seeds of different provenances, the correlation coefficient of linear regression was from -0.89--0.96, and the medial lethal doses (LD 50) of 10 provinces was from 127 Gy to 184 Gy. According to the LD 50, we could divided 10 provinces of J. curcas L. into sensitive provenance, transitional provenances and obtuse provenances. The provenances of Yuanjiang , Yunan (184 Gy) belonged to sensitive provenance; the provenances of Zhenfeng, Guizhou (127 Gy) and the provenances of Yuedong, Hainan (141 Gy) belonged to obtuse provenance; other 7 provenances belonged to transitional provenances. The results provided important experiment basis for germ plasma resources innovation of J. curcas L. (authors)
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In vitro degradation of poly (L-co-D,L lactic acid containing PCL-T
Directory of Open Access Journals (Sweden)
Marcia Adriana Tomaz Duarte
2014-01-01
Full Text Available The application of polymer-based bioresorbable temporary devices in the medical field grows continuously, and professionals from several areas act to solve problems related to body functions lost due to diseases, accidents or natural wear. Here we study the influence from poly(caprolactonetriol (PCL-T on the degeneration process in the copolymer poly(L-co-DL-lactic acid (PLDLA membrane, by producing PLDLA/PCL-T blends with 90/10, 70/30 and 50/50 relative concentrations. The data for in vitro degradation showed that PCL-T decreases the rate of PLDLA. This was obtained with the following techniques: Differential Scanning Calorimetry (DSC, Thermogravimetric Analysis (TGA, Gel Permeation Chromatography (GPC and Scanning Electron Microscopy (SEM. Therefore, it is possible to vary the membrane degradation rate by changing the blend composition, which is a tool to tailor a biomaterial.
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Genus Sisymbrium L. (Rockets In The Flora Of Latvia
Directory of Open Access Journals (Sweden)
Rūrāne Ieva
2015-04-01
Full Text Available One of the largest genera in the Cruciferae family in Latvia is Sisymbrium L. The genus includes not only native, but also some alien species. The distributions of the Sisymbrium species were reviewed for the first time in the last 50th years in Latvia. The distribution data were compiled from herbarium material, literature and field surveys. An identification key for the Sisymbrium species in Latvia and detailed scientific nomenclature are presented in the current study. In total, seven species of Sisymbrium were found in Latvia — S. supinum L., S. loeselii L., S. polymorphum (Murray Roth, S. volgense M. Bieb. ex E. Fourn., S. altissimum L., S. orientale L. and S. officinale (L. Scop. The mainly were recorded in railway verges, roadsides, waste dumps and wasteland. Five species of the genus are alien to the flora of Latvia — S. loeselii, S. altissimum, S. polymorphum, S. orientale, and S. volgense; two are native — S. supinum and S. officinale.
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International Nuclear Information System (INIS)
Smallwood, Sherin; Moyer, Sue A.
2004-01-01
We recently showed that the L protein of Sendai virus is present as an oligomer in the active P-L polymerase complex [Smallwood et al., Virology 304 (2002) 235]. We now demonstrate using two different epitope tags that the L protein of a second respirovirus, human parainfluenza type 3 virus (PIV3), also forms an L-L complex. L oligomerization requires the coexpression of the differentially epitope tagged L proteins. By exploiting a series of C-terminal truncations the L-L binding site maps to the N-terminal half of L. There is some complex formation between the heterologous PIV3 and Sendai L and P proteins; however, the heterologous L protein does not function in transcription of either the PIV3 or Sendai template. The PIV3 C protein binds PIV3 L and inhibits RNA synthesis in vitro and in vivo. Significant homology exists between the C proteins of PIV3 and Sendai and complex formation occurs between the PIV3 and Sendai heterologous C and L proteins. In addition, the heterologous C proteins can inhibit transcription at ∼50% of the level of the homologous protein. These data suggest that while the C proteins may be functionally somewhat interchangeable, the L and P proteins are specific for each virus
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Hussain, Altaf; Khan, Muhammad Nisar; Iqbal, Zafar; Sajid, Muhammad Sohail; Khan, Muhammad Kasib
2011-06-30
Evaluation of anthelmintic effects of Trianthema (T.) portulacastrum L. (Aizoaceae) whole plant and Musa (M.) paradisiaca L. (Musaceae) leaves against prevalent gastrointestinal worms of sheep was done that may justify their traditional use in veterinary clinical medicine. In vitro anthelmintic activity of the crude aqueous methanolic extract (CAME) of both the plants was determined using mature female Haemonchus (H.) contortus and their eggs in adult motility assay (AMA) and egg hatch test (EHT), respectively. In vivo anthelmintic activity of crude powder (CP) and CAME in increasing doses (1.0-8.0 g kg(-1)) was determined in sheep naturally infected with mixed species of nematodes using fecal egg count reduction test (FECRT) and larval counts. The study design also included untreated as well as treated controls. Fecal egg count reduction and larval counts from coprocultures were performed pre- and post-treatments to assess the anthelmintic activity of the plants. CAME of T. portulacastrum and M. paradisiaca showed a strong in vitro anthelmintic activity and pronounced inhibitory effects on H. contortus egg hatching as observed through AMA and EHT, respectively. Both plants exhibited dose and time dependent anthelmintic effects on live worms as well as egg hatching. M. paradisiaca (LC(50)=2.13 μg mL(-1)) was found to be more potent than T. portulacastrum (LC(50)=2.41 μg mL(-1)) in EHT. However, in vivo, maximum reduction in eggs per gram (EPG) of faeces was recorded as 85.6% and 80.7% with CAME of T. portulacastrum and M. paradisiaca at 8.0 g kg(-1) on 15th day post-treatment, respectively as compared to that of Levamisole (7.5 mg kg(-1)) that caused 97.0% reduction in EPG. All the species of gastrointestinal nematodes (GINs), i.e. Haemonchus contortus, Trichostronglyus spp., Oesophagostomum columbianum and Trichuris ovis which were prevalent, found susceptible (Pparadisiaca possess strong anthelmintic activity in vitro and in vivo, thus, justifying their use in
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Mendes, Lídia; de Freitas, Victor; Baptista, Paula; Carvalho, Márcia
2011-09-01
The present study reports the antioxidant properties of Arbutus unedo L. leaf and fruit extracts using different in vitro assays including (i) reducing power, (ii) scavenging effect on DPPH free radicals, and (iii) inhibitory effect on AAPH-induced hemolysis and lipid peroxidation in human erythrocytes. All assays demonstrated antioxidant efficiency for A. unedo L. aqueous extracts, being consistently higher in the leaf. EC(50) values for reducing power and DPPH radical scavenging activities were, respectively, 0.318 ± 0.007 and 0.087 ± 0.007 mg/mL for leaf, and 2.894 ± 0.049 and 0.790 ± 0.016 mg/mL for fruit extracts. Under the oxidative action of AAPH, A. unedo leaf and fruit extracts protected the erythrocyte membrane from hemolysis (IC(50) of 0.062 ± 0.002 and 0.430 ± 0.091 mg/mL, respectively) and decreased the levels of malondialdehyde, a breakdown product of lipid peroxidation (IC(50) of 0.075 ± 0.014 and 0.732 ± 0.452 mg/mL, respectively). In accordance with antioxidant activity, phenolic content was found to be significantly higher in leaf extract. To our knowledge, this is the first time that the antioxidant activity of A. unedo species is evaluated using human biological membranes. Overall, our results suggest that A. unedo leaves are a promising source of natural antioxidants with potential application in diseases mediated by free radicals. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Murray, Ana P; Gurovic, Maria S Vela; Rodriguez, Silvana A; Murray, María G; Ferrero, Adriana A
2009-06-01
The essential oils of Schinus areira L. and S. longifolia (Lindl.) Speg. (Anacardiaceae) have been studied for their in vitro anti-acetylcholinesterase and antioxidant activities. The chemical composition of the oils obtained by hydrodistillation was determined by GC-MS. Fruit and leaf oils of S. areira were analyzed separately. The essential oil from S. longifolia elicited marked enzymatic inhibition (IC50 = 20.0 +/- 1.0 microg/mL) and showed radical scavenger activity (IC50 = 25.2 +/- 2.4 microg/mL). The essential oil from S. areira leaves was more active than that of the fruits in both bioassays.
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Directory of Open Access Journals (Sweden)
María Olga Valdés Bendoyro
2010-03-01
Full Text Available Se desarrolló el estudio de estabilidad de las tabletas de propiltiouracilo 50 mg y se determinó su fecha de vencimiento. Este estudio se realizó por los métodos de vida de estante y de estabilidad acelerada mediante cromatografía líquida de alta eficiencia, validados en el Centro de Investigación y Desarrollo de Medicamentos. El estudio de vida de estante se desarrolló por un periodo de 24 meses a temperatura ambiente; mientras que el estudio de estabilidad acelerada se efectuó sometiendo el producto a la influencia de la luz, la humedad y la temperatura; se realizó el análisis durante 3 meses, para los 2 primeros y durante 6 meses para el estudio de la temperatura. La formulación de propiltiouracilo tabletas 50 mg cumplió con las especificaciones de calidad descritas en la farmacopea. Los resultados del estudio de estabilidad por vida de estante después de transcurridos los 24 meses indicaron que el producto mantenía los parámetros que determinan su calidad durante ese tiempo, y en los estudios acelerados no se observó degradación significativa del producto. Se estableció 2 años como fecha de vencimiento en las condiciones señaladas.Autors developed a stability study of 50 mg Propylthiouracil tablets and determination of its expiry date. This study was conducted by fixed life methods and of accelerated stability by high-performance liquid chromatography, validated in Drugs Research and Development Center. Fixed life study was conducted during 24 months at room temperature; whereas the accelerated stability study was conducted exposing the product to light influence, humidity and temperature; during 3 months a analysis was performed for the two first ones and over 6 months in the case of temperature study. Propylthiouracil formula (50 mg tablets fulfilled the quality specifications described in Pharmacopeia. Results of stability study by fixed life after 24 monhts showed that thr product maintain the parameter determining
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Phytochemical analysis and antioxidant activity of Hyssopus officinalis L. from Iran
Directory of Open Access Journals (Sweden)
Fatemeh Fathiazad
2011-12-01
Full Text Available Introduction: Hyssopus officinalis (L (Hyssop, Family: Lamiaceae, one of the endemic Iranian perennial herb with a long history of medicinal use, was studied to detect some biologically active chemical constituents of the plant. Methods: The flavonoids of the hydromethanolic extract of the aerial parts of Hyssopus officinalis (L. were studied by VLC and crystalisation of the major compound in subsequent fractions. Furthermore, the composition of its essential oil, total phenolic content and antioxidant activities were studied by GC-MS, Folin–Ciocalteau and DPPH reagents respectively. Results: Apigenin 7-O-β-D-glucuronide was isolated as the major flavonoid. All structural elucidation was performed by spectral means. A total of 20 compounds representing 99.97% of the oil have been identified. Myrtenylacetate , Camphor, Germacrene, Spathulenol were the main compounds The total phenol content of the n-butanol and ethylacetate extracts were determined spectrophotometrically according to the Folin–Ciocalteau procedure to be 246 mgGAE g-1 and 51 mgGAE g-1 in the aerial parts of Hyssopus officinalis. The antioxidant activities of apigenin 7-O-β-D-glucuronide, ethylacetate and n-butanol extracts were also determined by DPPH radical scavenging assay with IC50 values of 116×10_3, 103×10_3, 25×10_3 mg mL-1 respectively. The purified flavonoid showed weak radical scavenging activity (IC50 = 116×10_3mg mL_1. N-butanol extract, because of the highest content of total phenolic compounds (246 mgGAE100_1g had the best antioxidant activity (IC50 = 25mg mL_1. Conclusion: On the whole, the findings of the study revealed that Hyssop possesses valuable antioxidant properties for culinary and possible medicinal use.
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Figueirôa, Evellyne de Oliveira; Nascimento da Silva, Luís Cláudio; de Melo, Cristiane Moutinho Lagos; Neves, Juliana Kelle de Andrade Lemoine; da Silva, Nicácio Henrique; Pereira, Valéria Rêgo Alves; Correia, Maria Tereza dos Santos
2013-01-01
An increasing number of biological activities presented by medicinal plants has been investigated over the years, and they are used in the search for new substances with lower side effects. Eugenia uniflora L. and Eugenia malaccensis L. (Myrtaceae) have many folk uses in various countries. This current study was designed to quantify the polyphenols and flavonoids contents and evaluate the immunomodulatory, antioxidant, and cytotoxic potentials of fractions from E. uniflora L. and E. malaccensis L. It was observed that the polyphenol content was higher in ethyl acetate fractions. These fractions have high antioxidant potential. E. malaccensis L. seeds showed the largest DPPH radical scavenger capacity (EC50 = 22.62). The fractions of E. malaccensis L. leaves showed lower antioxidant capacity. The samples did not alter the profile of proinflammatory cytokines and nitric oxide release. The results indicate that species of the family Myrtaceae are rich in compounds with antioxidant capacity, which can help reduce the inflammatory response.
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Directory of Open Access Journals (Sweden)
Caridad M García Peña
2008-04-01
Full Text Available Se validó un método para evaluar la disolución de las tabletas de propiltiuracilo 50 mg por espectrofotometría, con detección ultravioleta a 274 nm. Se evaluaron los parámetros de especificidad, linealidad, precisión e influencia de la filtración. La curva de linealidad se realizó en el rango de 3,32 a 7,75 µg/mL con un coeficiente de correlación igual a 0,99984; la prueba estadística para el intercepto y la pendiente se consideró no significativa. En el estudio de la influencia de la filtración se demostró que en la filtración no se adsorbe el principio activo ni se aportan interferencias al filtrado, por lo que es posible su empleoA method to evaluate the dissolution of propylthiouracil tablets 50 mg by spectrophotometry, with ultraviolet detection of 274 nm, was validated. Specificity, linearity, precision and filtration influence were the evaluated parameters. The linearity curve was made at the range from 3.32 to 7.75 µg/mL with a correlation coefficient equal to 0.99984. The statistical test for the interval and the slope was not significant. In the study of filtration influence it was proved that the active principle was not absorbed in the filtration and that there were no interferences in the filtration, which made its use possible
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Zhao, Ting Ting; Kim, Kyung Sook; Shin, Keon Sung; Park, Hyun Jin; Kim, Hyun Jeong; Lee, Kyung Eun; Lee, Myung Koo
2017-09-06
Previous studies have revealed that gypenosides (GPS) improve the symptoms of anxiety disorders in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned rat model of Parkinson's disease (PD). The present study aimed to investigate the effects of GPS on memory deficits in an MPTP-lesioned mouse model of PD treated with L-3,4-dihydroxyphenylalanine (L-DOPA). MPTP (30 mg/kg/day, 5 days)-lesioned mice were treated with GPS (50 mg/kg) and/or L-DOPA (10 and 25 mg/kg) for 21 days. After the final treatments, behavioral changes were assessed in all mice using passive avoidance and elevated plus-maze tests. We then evaluated the biochemical influences of GPS treatment on levels of tyrosine hydroxylase (TH), dopamine, N-methyl-D-aspartate (NMDA) receptors, extracellular signal-regulated kinase (ERK1/2), and cyclic AMP-response element binding protein (CREB) phosphorylation. MPTP-lesioned mice exhibited deficits associated with habit learning and spatial memory, which were further aggravated by treatment with L-DOPA (25 mg/kg). However, treatment with GPS (50 mg/kg) ameliorated memory deficits. Treatment with GPS (50 mg/kg) also improved L-DOPA (25 mg/kg)-treated MPTP lesion-induced decreases in retention latency on the passive avoidance test, as well as levels of TH-immunopositive cells and dopamine in the substantia nigra and striatum. GPS treatment also attenuated increases in retention transfer latency on the elevated plus-maze test and in NMDA receptor expression, as well as decreases in the phosphorylation of ERK1/2 and CREB in the hippocampus. Treatment with L-DOPA (10 mg/kg) also ameliorated deficits in habit learning and spatial memory in MPTP-lesioned mice, and this effect was further enhanced by treatment with GPS (50 mg/kg). GPS ameliorate deficits in habit learning and spatial memory by modulating the dopaminergic neuronal and N-methyl-D-aspartate receptor-mediated signaling systems in MPTP-lesioned mice treated with L-DOPA. GPS may serve as an adjuvant
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Directory of Open Access Journals (Sweden)
R. Krejčí
2006-01-01
Full Text Available Potassium dichromate (K2Cr2O7 has already been used as a reference substance in tests of toxicity with aquatic animals. The aim of this study was to determine and compare values of LC50 for potassium dichromate during the whole period of embryonic development (i.e., 120 h and 48 h after hatching of embryos in the common carp (Cyprinus carpio L.. Fish eggs and embryos were exposed to 5 different concentrations of potassium dichromate (i.e., 372, 409, 450, 495, 545 mg l-1 during two experiments. Such characteristics as the cumulative mortality, the start and the end of hatching, the number of deformities, body length, and body mass of surviving individuals were studied during the tests. The highest mortality was found in the hatched embryos. Mortality and frequency of deformities increased with the growing concentration of potassium dichromate. The value of 120 LC50 for potassium dichromate was 464.91 ± 23.83 mg l-1 and the value of 48 LC50 was 458.94 ± 4.14 mg l-1 (mean ± SD. No statistically significant difference between values 120 LC50 a 48 LC50 was found. This is why reduction of the exposure period to only 48 h after hatching seems a reasonable method to study the control of susceptibility using potassium dichromate in embryonic tests of toxicity.
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Directory of Open Access Journals (Sweden)
A. Ghanbari
2016-04-01
Full Text Available In order to evaluate millet (Panicum miliaceum L. and cowpea (Vigna unguiculata L. intercropping, an experiment was conducted during 2008-2009 at Agriculture Research Center of Zabol University, Iran. The experiment was as randomized complete block design with three replications. Treatment s consisted of sole crop of millet, sole crop of cowpea, 25% millet + 100% cowpea, 50% millet + 50% cowpea, 75% millet + 100% cowpea and 100% millet + 100% cowpea. The results showed that intercropping treatments had significant effect (P < 1% on millet and bean seed yield, LER, dry matter of weeds, PAR, temperature and (P < 5% on soil moisture content. The highest seed yield of millet and cowpea obtained from treatments of sole crops. The LER for most intercrops was greater than one which indicated that intercropping had advantage over sole crop. For weeds management and control the results indicated that weed suppressing effects in intercropping treatments is better than sole crops treatment, so that the lowest dry matter of weeds obtained from 100% millet + 100% cowpea treatment. PAR in all of stages showed that the highest PAR interception obtained from intercropping treatments specially 100% millet + 100% cowpea treatment. In addition to the lowest of soil moisture content and temperature obtained from this treatment.
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Wang, Shuzhen; Zheng, Yongliang; Xiang, Fu; Li, Shiming; Yang, Guliang
2016-10-01
Momordica charantia L., a vegetable crop with high nutritional value, has been used as an antimutagenic, antihelminthic, anticancer, antifertility, and antidiabetic agent in traditional folk medicine. In this study, the antifungal activity of M. charantia seed extract toward Fusarium solani L. was evaluated. Results showed that M. charantia seed extract effectively inhibited the mycelial growth of F. solani, with a 50% inhibitory rate (IC 50 ) value of 108.934 μg/mL. Further analysis with optical microscopy and fluorescence microscopy revealed that the seed extract led to deformation of cells with irregular budding, loss of integrity of cell wall, as well as disruption of the fungal cell membrane. In addition, genomic DNA was also severely affected, as small DNA fragments shorter than 50 bp appeared on agarose gel. These findings implied that M. charantia seed extract containing α-momorcharin, a typical ribosome-inactivating protein, could be an effective agent in the control of fungal pathogens, and such natural products would represent a sustainable alternative to the use of synthetic fungicides. Copyright © 2016. Published by Elsevier B.V.
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Pharmacological effects of the phytochemicals of Anethum sowa L. root extracts.
Saleh-E-In, Md Moshfekus; Sultana, Nasim; Hossain, Md Nur; Hasan, Sayeema; Islam, Md Rabiul
2016-11-14
Anethum sowa L. is widely used as an important spice and traditional medicinal plants to treat various ailments. On the basis of scientific ethnobotanical information, this study was undertaken to evaluate the antioxidant, antimicrobial and cytotoxic activity of the crude extracts of Anethum sowa L. roots as well as to identify the classes of phytochemicals by chemical tests. The antioxidant potential of the extracts was ascertained with the stable organic free radical (2, 2-diphenyl-1-picryl-hydrazyl). The agar well diffusion method was used to determine the susceptibility of bacterial and fungal strains of the crude extracts. The minimum inhibitory concentration (MIC) and minimum bactericidal concentrations (MBC) were determined by the microdilution test. Cytotoxic activities were screened using brine shrimps (Artemia salina) lethality assay. Finally, phytochemicals were profiled using standard procedures. A preliminary phytochemical screening of the different crude extracts by methanol, ethyl acetate and chloroform showed the presence of secondary metabolites such as flavonoids, alkaloids, saponin, cardiac glycosides and tannins while cyanogenetic glycosides were not detected. The methanol, ethyl acetate and chloroform extracts displayed high antioxidant activity (IC 50 = 13.08 ± 0.03, 33.48 ± 0.16 and 36.42 ± 0.41 μg/mL, respectively) in the DPPH assay comparable to that of the standard ascorbic acid and BHT (IC 50 = 3.74 ± 0.05 and 11.84 ± 0.29 μg/mL). The cytotoxic activity of the crude ethyl acetate and chloroform extracts possessed excellent activity (LC 50 = 5.03 ± 0.08, 5.23 ± 0.11 and 17.22 ± 0.14 μg/mL, respectively) against brine shrimp larvae after 24 h of treatment and compared with standard vincristine sulphate (LC 50 = 0.46 ± 0.05 μg/mL). The extracts also showed good antimicrobial activity against both Gram-positive and Gram-negative bacteria when compared with two standard
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Cestonaro, Taiana; Costa, Mônica Sarolli Silva de Mendonça; Costa, Luiz Antônio de Mendonça; Rozatti, Marcos Antonio Teofilo; Pereira, Dercio Ceri; Lorin, Higor Eisten Francisconi; Carneiro, Leocir José
2015-12-01
Sheep manure pellets are peculiarly shaped as small 'capsules' of limited permeability and thus are difficult to degrade. Fragmentation of manure pellets into a homogeneous mass is important for decomposition by microorganisms, and occurs naturally by physical shearing due to animal trampling, when sheep bedding is used. However, the high lignocellulose content of sheep bedding may limit decomposition of sheep manure. Here, we evaluated if co-digestion of sheep bedding with cattle manure would improve the yield and quality of the useful products of anaerobic digestion of sheep bedding--biogas and biofertilizer--by providing a source of nutrients and readily available carbon. Mixtures of sheep bedding and cattle manure in varying proportions (0%, 25%, 50%, 75%, or 100% cattle manure) were added to 6-L digesters, used in a batch system, and analyzed by uni and multivariate statistical tools. PC1, which explained 64.96% of data variability, can be referred to as 'organic fraction/productivity', because higher rates of organic fraction consumption (COD, cellulose and hemicellulose contents) led to higher digester productivity (biogas production, nutrient concentration, and sample stability changes). Therefore, productivity and organic fraction variables were most influenced by manure mixtures with higher (⩾ 50%) or lower (⩽ 25%) ratios of cattle manure, respectively. Increasing the amount of cattle manure up to 50% enhanced the biogas potential production from 142 L kg(-1)TS (0% of cattle manure) to 165, 171, 160 L biogas kg(-1)TS for the mixtures containing 100%, 75% and 50% of cattle manure, respectively. Our results show that the addition of ⩾ 50% cattle manure to the mixture increases biogas production and improves the quality of the final biofertilizer. Copyright © 2015 Elsevier Ltd. All rights reserved.
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International Nuclear Information System (INIS)
Alves, Juliana Nazare; Potenza, Marcos Roberto
2008-01-01
Stores products such a grains, flours, dry fruits and spices are normally infested by pests as beetles (Lasioderma serricorne), mites and moths, depreciating the product visually and promoting its deterioration. To improve the quality of spices, medicinal plants and others foodstuffs there is a need for adequate methods of handling, correct identification of the species, adequate collection and storage. The objective of this work was to determine the dose of gamma radiation for the disinfestation of medicinal and aromatic plants infested by L. serricorne. The plants used in this study were Chamomilla recutita L. and Pimpinela anisum L. in this dehydrated form. The experiment was carried out in the Laboratorio de Inseticidas e Acaricidas from Instituto Biologico/SP, during the months of January and May 2006, and the irradiations were carried out in the Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN/SP, using and experimental Cobalt 60 irradiator, model Gammacell 220. Each treatment consisted of 5 parcels containing 10 g of dehydrated products infested with 20 last instar larvae of L. serricorne, conditioned in plastic 10 x 10 cm containers with small punctures in the cover to allow internal aeration. The substratum previously infested was submitted to increasing doses of gamma radiation: 0: 0.5; 0.75; 1.0; 1.25; 1.50; 1.75; 2.0; 2.25; 2.50 and 2.75 kGy. After irradiation, the samples were kept in a acclimatized room at 27 ± 2 deg C of temperature and relative humidity of 70 ± 5% and after a 45 days period the number of adults insects emerged was evaluated. The disinfestation dose of gamma radiation for last instar larvae L. serricorne on Chamomilla recutita L. and Pimpinela anisum L. was 2.0 kGy. (author)
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Energy Technology Data Exchange (ETDEWEB)
Alves, Juliana Nazare; Potenza, Marcos Roberto [Instituto Biologico, Sao Paulo, SP (Brazil). Centro de Pesquisa e Desenvolvimento de Sanidade Vegetal]. E-mail: julianaabc@ig.com.br; Arthur, Valter [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)]. E-mail: arthur@cena.usp.br
2008-03-15
Stores products such a grains, flours, dry fruits and spices are normally infested by pests as beetles (Lasioderma serricorne), mites and moths, depreciating the product visually and promoting its deterioration. To improve the quality of spices, medicinal plants and others foodstuffs there is a need for adequate methods of handling, correct identification of the species, adequate collection and storage. The objective of this work was to determine the dose of gamma radiation for the disinfestation of medicinal and aromatic plants infested by L. serricorne. The plants used in this study were Chamomilla recutita L. and Pimpinela anisum L. in this dehydrated form. The experiment was carried out in the Laboratorio de Inseticidas e Acaricidas from Instituto Biologico/SP, during the months of January and May 2006, and the irradiations were carried out in the Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN/SP, using and experimental Cobalt 60 irradiator, model Gammacell 220. Each treatment consisted of 5 parcels containing 10 g of dehydrated products infested with 20 last instar larvae of L. serricorne, conditioned in plastic 10 x 10 cm containers with small punctures in the cover to allow internal aeration. The substratum previously infested was submitted to increasing doses of gamma radiation: 0: 0.5; 0.75; 1.0; 1.25; 1.50; 1.75; 2.0; 2.25; 2.50 and 2.75 kGy. After irradiation, the samples were kept in a acclimatized room at 27 {+-} 2 deg C of temperature and relative humidity of 70 {+-} 5% and after a 45 days period the number of adults insects emerged was evaluated. The disinfestation dose of gamma radiation for last instar larvae L. serricorne on Chamomilla recutita L. and Pimpinela anisum L. was 2.0 kGy. (author)
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International Nuclear Information System (INIS)
2008-11-01
This document presents the 50 measures decided by the government to develop the renewable energies in France and reach the 20% of participation to the energy production in 2020. Some measures concern all the renewable energies, they deal with the regulation, the administrative procedures of the building, others are specific to each energy. (A.L.B.)
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Kusbandari, A.; Susanti, H.
2017-11-01
Maranta arundinacea L is one of herbaceous plants in Indonesia which have flavonoid content. Flavonoids has antioxidants activity by inhibition of free radical oxidation reactions. The study aims were to determination total phenolic content and antioxidant activity of methanol extract of fresh leaf and tuber of M. arundinacea L by UV-Vis spectrophotometer. The methanol extracts were obtained with maceration and remaseration method of fresh leaves and tubers. The total phenolic content was assayed with visible spectrophotometric using Folin Ciocalteau reagent. The antioxidant activity was assayed with 1,1-diphenyl-2-picrilhidrazil (DPPH) compared to gallic acid. The results showed that methanol extract of tuber and fresh leaf of M. arundinacea L contained phenolic compound with total phenolic content (TPC) in fresh tuber of 3.881±0.064 (% GAE) and fresh leaf is 6.518±0.163 (% b/b GAE). IC50 value from fresh tuber is 1.780±0.0005 μg/mL and IC50 fresh leaf values of 0.274±0.0004 μg/mL while the standard gallic acid is IC50 of 0.640±0.0002 μg/mL.
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Zarai, Zied; Ben Chobba, Ines; Ben Mansour, Riadh; Békir, Ahmed; Gharsallah, Néji; Kadri, Adel
2012-08-13
The aim of the present study was to appraise the antimicrobial activity of Ricinus communis L. essential oil against different pathogenic microorganisms and the cytotoxic activity against HeLa cell lines. The agar disk diffusion method was used to study the antibacterial activity of Ricinus communis L. essential oil against 12 bacterial and 4 fungi strains. The disc diameters of zone of inhibition (DD), the minimum inhibitory concentrations (MIC) and the concentration inhibiting 50% (IC50) were investigated to characterize the antimicrobial activities of this essential oil. The in vitro cytotoxicity of Ricinus communis L. essential oil was examined using a modified MTT assay; the viability and the IC50 were used to evaluate this test. The essential oil from the leaves of Ricinus communis L. was analyzed by GC-MS and bioassays were carried out. Five constituents of the oil were identified by GC-MS. The antimicrobial activity of the oil was investigated in order to evaluate its efficacy against twelve bacteria and four fungi species, using disc diffusion and minimum inhibitory concentration methods. The essential oil showed strong antimicrobial activity against all microorganisms tested with higher sensitivity for Bacillus subtilis, Staphylococcus aureus and Enterobacter cloacae. The cytotoxic and apoptotic effects of the essential oil on HeLa cell lines were examined by MTT assay. The cytotoxicity of the oil was quite strong with IC50 values less than 2.63 mg/ml for both cell lines. The present study showed the potential antimicrobial and anticarcinogenic properties of the essential oil of Ricinus communis L., indicating the possibilities of its potential use in the formula of natural remedies for the topical treatment of infections.
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UJI AKTIVITAS ANTIOKSIDAN DARI EKSTRAK JANTUNG PISANG KEPOK (MUSA PARADISIACA L. PONTIANAK
Directory of Open Access Journals (Sweden)
Ade Ferdinan
2018-03-01
Full Text Available Antioxidant Activity of Ethanol Extract of Banana Kepok Flower (Musa paradisiaca L. with UV-Vis Spectrophotometric Method. This research is intended to know the antioxidant activity of ethanol ekstrak of banana kepok by qualitative and quantitative method of DPPH, with UV-Vis spectrophotometry at 517 nm wavelength. Extract of banana kepok flower is made in concentrations of 4 ppm, 8 ppm, 12 ppm, 16 ppm, and 20 ppm. As a comparison used vitamin C. The results of IC50 ethanol extract of banana kepok flower (Musa paradisiaca L. is 13.11 ppm and vitamin C is 1.11 ppm. If IC50 is smaller than 200 ppm, it can be used as an antioxidant.
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Directory of Open Access Journals (Sweden)
Abdoul Habou, Z.
2014-01-01
Full Text Available Influence of the Conservation Mode of Jatropha curcas L. oil on its Efficacy in the Control of Major Insect Pests of Cowpea (Vigna unguiculata (L. Walp in Niger. Jatropha curcas oil has an insecticidal activity harnessed by the farmers in Niger. In this study, we compared the insecticidal activity of two batches of oil conserved during 70 days, one exposed to light and the other kept in the dark. The insecticidal efficacy was evaluated in a field with three concentrations (5, 10 and 15% trial on the main pests of Cowpea (Vigna unguiculata (L. Walp and in a laboratory test on Megalurothrips sjostedti Trybon (Thysanoptera: Thripidae with different concentrations of crude oil (50; 100; 150 and 200 µl. No difference in insecticidal effect was found between the two modes of oil conservation, both in the laboratory and in the field. In the field, regardless of the mode of conservation, the concentrations of 10% of J. curcas oil enables a reduction of over than 80% of thrips, aphids, and bugs compared to the control. Its increased seeds yield more than 50%. The concentration of 15% gives an insecticidal effect comparable to that of the reference treatment (deltaméthrine but induces phytotoxicity symptoms on the leaves of Cowpea.
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Directory of Open Access Journals (Sweden)
Meriem TOUAIBIA
2016-05-01
Full Text Available Myrtus nivellei Batt & Trab. est une plante saharo-endémique, très réputée au sud algérien pour ses vertus thérapeutiques en médecine populaire. Cependant, ses usages restent, toutefois, exclusivement limités au savoir-faire ancestral. Ce travail apporte une première contribution à l'investigation du pouvoir anti-oxydant des extraits méthanoliques de cette espèce récoltée in situ ainsi que des cals multipliés in vitro. Les analyses spectrophotométriques effectuées ont montré que l'extrait méthanolique de la plante récoltée in situ s'est avéré plus riche en polyphenols par rapport à l'extrait des cals. Il a éventuellement exprimé un bon pouvoir de capture des radicaux libres avec une EC50=0,98 mg/ml, et un très bon pouvoir inhibiteur de la peroxydation de l'acide linoléique estimé à 74,01%, qui s'est avéré largement supérieur à celui exprimé par l'acide ascorbique (50,57% utilisé comme contrôle positif. Néanmoins, les extraits méthanoliques préparés à partir des cals ont exprimé le meilleur pouvoir chélateur des ions Fe2+ estimé à 66,71%.
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MacDill Air Force Base: National Register Eligibility Recommendations for Sites 8HI50 and 8HI5656
National Research Council Canada - National Science Library
Gerrell, Philip
1997-01-01
...). The excavation methodology involved the hand excavation of systematically placed 50-x-5O-cm shovel tests and l-x-1-m excavation units to determine the horizontal and vertical dimensions of the site deposits...
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Energy Technology Data Exchange (ETDEWEB)
Tijink, Bernard M.; Perk, Lars R.; Budde, Marianne; Stigter-van Walsum, Marijke; Leemans, C.R. [VU University Medical Center, Department of Otolaryngology/Head and Neck Surgery, Amsterdam (Netherlands); Visser, Gerard W.M.; Kloet, Reina W. [VU University Medical Center, Nuclear Medicine and PET Research, Amsterdam (Netherlands); Dinkelborg, Ludger M. [Bayer Schering Pharma AG, Global Drug Discovery, Berlin (Germany); Neri, Dario [Swiss Federal Institute of Technology, Institute of Pharmaceutical Sciences, Zurich (Switzerland); Dongen, Guus A.M.S. van [VU University Medical Center, Department of Otolaryngology/Head and Neck Surgery, Amsterdam (Netherlands); VU University Medical Center, Nuclear Medicine and PET Research, Amsterdam (Netherlands)
2009-08-15
The human monoclonal antibody (MAb) fragment L19-SIP is directed against extra domain B (ED-B) of fibronectin, a marker of tumour angiogenesis. A clinical radioimmunotherapy (RIT) trial with {sup 131}I-L19-SIP was recently started. In the present study, after GMP production of {sup 124}I and efficient production of {sup 124}I-L19-SIP, we aimed to demonstrate the suitability of {sup 124}I-L19-SIP immuno-PET for imaging of angiogenesis at early-stage tumour development and as a scouting procedure prior to clinical {sup 131}I-L19-SIP RIT. {sup 124}I was produced in a GMP compliant way via {sup 124}Te(p,n){sup 124}I reaction and using a TERIMO trademark module for radioiodine separation. L19-SIP was radioiodinated by using a modified version of the IODO-GEN method. The biodistribution of coinjected {sup 124}I- and {sup 131}I-L19-SIP was compared in FaDu xenograft-bearing nude mice, while {sup 124}I PET images were obtained from mice with tumours of <50 to {proportional_to}700 mm{sup 3}. {sup 124}I was produced highly pure with an average yield of 15.4 {+-} 0.5 MBq/{mu}Ah, while separation yield was {proportional_to}90% efficient with <0.5% loss of TeO{sub 2}. Overall labelling efficiency, radiochemical purity and immunoreactive fraction were for {sup 124}I-L19-SIP: {proportional_to}80, 99.9 and >90%, respectively. Tumour uptake was 7.3{+-}2.1, 10.8{+-}1.5, 7.8{+-}1.4, 5.3{+-}0.6 and 3.1{+-}0.4%ID/g at 3, 6, 24, 48 and 72 h p.i., resulting in increased tumour to blood ratios ranging from 6.0 at 24 h to 45.9 at 72 h p.i. Fully concordant labelling and biodistribution results were obtained with {sup 124}I- and {sup 131}I-L19-SIP. Immuno-PET with {sup 124}I-L19-SIP using a high-resolution research tomograph PET scanner revealed clear delineation of the tumours as small as 50 mm{sup 3} and no adverse uptake in other organs. {sup 124}I-MAb conjugates for clinical immuno-PET can be efficiently produced. Immuno-PET with {sup 124}I-L19-SIP appeared qualified for sensitive
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Local atomic structure inheritance in Ag50Sn50 melt
International Nuclear Information System (INIS)
Bai, Yanwen; Bian, Xiufang; Qin, Jingyu; Hu, Lina; Yang, Jianfei; Zhang, Kai; Zhao, Xiaolin; Yang, Chuncheng; Zhang, Shuo; Huang, Yuying
2014-01-01
Local structure inheritance signatures were observed during the alloying process of the Ag 50 Sn 50 melt, using high-temperature X-ray diffraction and ab initio molecular dynamics simulations. The coordination number N m around Ag atom is similar in the alloy and in pure Ag melts (N m ∼ 10), while, during the alloying process, the local structure around Sn atoms rearranges. Sn-Sn covalent bonds were substituted by Ag-Sn chemical bonds, and the total coordination number around Sn increases by about 70% as compared with those in the pure Sn melt. Changes in the electronic structure of the alloy have been studied by Ag and Sn K-edge X-ray absorption spectroscopy, as well as by calculations of the partial density of states. We propose that a leading mechanism for local structure inheritance in Ag 50 Sn 50 is due to s-p dehybridization of Sn and to the interplay between Sn-s and Ag-d electrons
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African Journals Online (AJOL)
chifaou.amzat
19 mai 2017 ... génocide et crimes d'agression, la CPI fait face à des critiques très acerbes ...... président Bush signe, le 2 août 2002, la loi ASPA50 qui est à ...... permanente du financement du secteur de la justice, l'absence de volonté de.
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Do L5 and s1 nerve root compressions produce radicular pain in a dermatomal pattern?
Taylor, Christopher S; Coxon, Andrew J; Watson, Paul C; Greenough, Charles G
2013-05-20
Observational case series. To compare the pattern of distribution of radicular pain with published dermatome charts. Dermatomal charts vary and previous studies have demonstrated significant individual subject variation. Patients with radiologically and surgically proven nerve root compression (NRC) caused by prolapsed intervertebral disc completed computerized diagrams of the distribution of pain and pins and needles. Ninety-eight patients had L5 compressions and 83 had S1 compressions. The distribution of pain and pins and needles did not correspond well with dermatomal patterns. Of those patients with L5 NRC, only 22 (22.4%) recorded any hits on the L5 dermatome on the front, and only 60 (61.2%) on the back with only 13 (13.3%) on both. Only 1 (1.0%) patient placed more than 50% of their hits within the L5 dermatome. Of those patients with S1 NRC, only 3 (3.6%) recorded any hits on the S1 dermatome on the front, and only 64 (77.1%) on the back with only 15 (18.1%) on both. No patients placed more than 50% of their hits within the S1 dermatome. Regarding pins and needles, 27 (29.7%) patients with L5 NRC recorded hits on the front alone, 27 (29.7%) on the back alone, and 14 (15.4%) on both. Nineteen (20.9%) recorded more than 50% of hits within the L5 dermatome. Three (3.6%) patients with S1 NRC recorded hits on the front alone, 44 (53.0%) on the back alone, and 18 (21.7%) on both. Twelve (14.5%) recorded more than 50% of hits within the S1 dermatome. Patient report is an unreliable method of identifying the anatomical source of pain or paresthesia caused by nerve root compression. 4.
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Growth and development of Mentha piperita L. in nutrient solution as affected by rates of potassium
Directory of Open Access Journals (Sweden)
Janice Valmorbida
2007-05-01
Full Text Available The influence of potassium on the development of Mentha piperita L. was evaluated in the plants grown in nutritive solution modified by variations in potassium, at 6.0, 3.0, and 1.5 mmol L-1, establishing differences between treatments and corresponding, respectively, to the concentration proposed in Hoagland and Arnon's no. 2 solution and reductions by 50% and 75%. Until 21 days after transplanting, the concentration used was diluted to 50% in the three treatments. Evaluations consisted of leaf area, development of the above-ground part, and dry matter of different plant organs. Plants grown with 1.5/3.0 mmol L-1 K showed greater development of the above-ground part. Other variables were not different among plants in the different treatments.A influência do potássio no desenvolvimento de Mentha piperita L. foi avaliada em plantas cultivadas em solução nutritiva modificada pela variação de potássio, com 6.0, 3.0 e 1.5 mmol L-1, que estabeleceram as diferenças entre tratamentos e corresponderam, respectivamente, a sua concentração proposta na solução nº 2 de Hoagland e Arnon e diminuição em 50% e 75%. Até os 21 dias após o transplante a concentração utilizada foi diluída em 50% nos três tratamentos. Avaliou-se área foliar, desenvolvimento da parte aérea e matéria secas dos diferentes órgãos. Plantas cultivadas com 1.5/3.0 mmol L-1 K apresentaram maior desenvolvimento da parte aérea. Demais variáveis não diferiram entre as plantas dos diferentes tratamentos.
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Escudero, Andrea; Petzold, Guillermo; Moreno, Jorge; Gonzalez, Marcelo; Junod, Julio; Aguayo, Claudio; Acurio, Jesenia; Escudero, Carlos
2013-01-01
Supplementation with L-arginine or fresh food with high content of this amino acid is associated with favorable effects in the metabolic control of diabetes. We aimed to determine whether supplementation with apples enriched with L-arginine offer additional benefits compared to L-arginine by itself in a preclinical study of diabetes. This study combines food-engineer technologies with in vivo and in vitro analysis. In vitro experiments show that cells derived from non-diabetic animals and exposed to high glucose (25 mM, 12 H) and cells isolated from alloxan-induced diabetic animals exhibited a reduction (∼50%) in the L-arginine uptake. This effect was reverted by L-arginine pretreatment (12 H) in both the normal and diabetes-derived cells. In preclinical studies, normoglycemic (n = 25) and diabetic groups (n = 50) were divided into subgroups that received either L-arginine (375 mg/kg per 10 days) or apple enriched with L-arginine or vehicle (control). In a preliminary analysis, supplementation with L-arginine by itself (50%) or apple enriched with L-arginine (100%) improve survival rate in the diabetic group compared to control (0%) at the end of the follow up (17 days). This phenomenon was associated with a partial but sustained high plasma level of L-arginine, as well as plasma concentration of nitrites and insulin in the L-arginine or apple + L-arginine groups after supplementation. Apple + L-arginine supplementation in diabetic animals induced the highest and longest effects in the level of these three markers among the studied groups. Therefore, apple enriched by L-arginine offers more benefits than L-arginine by itself in this preclinical study. Copyright © 2013 International Union of Biochemistry and Molecular Biology, Inc.
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Directory of Open Access Journals (Sweden)
Piotr Michel
2017-03-01
Full Text Available The phytochemical profile and anti-inflammatory activity of Gaultheria procumbens dry lipophilic leaf extracts were evaluated. Forty compounds were identified by GC-MS, representing 86.36% and 81.97% of the petroleum ether (PE and chloroform (CHE extracts, respectively, with ursolic acid (28.82%, oleanolic acid (10.11%, methyl benzoate (10.03%, and methyl salicylate (6.88% dominating in CHE, and methyl benzoate (21.59%, docosane (18.86%, and octacosane (11.72% prevailing in PE. Three components of CHE were fully identified after flash chromatography isolation and spectroscopic studies as (6S,9R-vomifoliol (4.35%, 8-demethyl-latifolin (1.13%, and 8-demethylsideroxylin (2.25%. Hyaluronidase and lipoxygenase inhibitory activity was tested for CHE (IC50 = 282.15 ± 10.38 μg/mL and 899.97 ± 31.17 μg/mL, respectively, PE (IC50 = 401.82 ± 16.12 μg/mL and 738.49 ± 15.92 μg/mL, and nine of the main constituents versus heparin (IC50 = 366.24 ± 14.72 μg/mL and indomethacin (IC50 = 92.60 ± 3.71 μg/mL as positive controls. With the best activity/concentration relationships, ursolic and oleanolic acids were recommended as analytical markers for the extracts and plant material. Seasonal variation of both markers following foliar development was investigated by UHPLC-PDA. The highest levels of ursolic (5.36–5.87 mg/g DW of the leaves and oleanolic (1.14–1.26 mg/g DW acids were observed between August and October, indicating the optimal season for harvesting.
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Czech Academy of Sciences Publication Activity Database
Lauková, A.; Strompfová, V.; Skřivanová, V.; Volek, Z.; Jindřichová, E.; Marounek, Milan
2006-01-01
Roč. 61, č. 6 (2006), s. 779-782 ISSN 0006-3088. [ Probiotic Conference /2./. Košice, 15.09.2006-19.09.2006] Grant - others:VEGA 2/5139/25 Institutional research plan: CEZ:AV0Z50450515 Keywords : probiotic * bacteriocin * enterocin Subject RIV: GH - Livestock Nutrition Impact factor: 0.213, year: 2006
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Alvarez, Guillermo; Caldwell, Colleen A.; Kruse, Carter G.
2017-01-01
Amphibians may experience collateral effects if exposed to CFT Legumine (5% rotenone), a piscicide that is used to remove invasive fish. A series of 48-h static toxicity tests assessed the acute effects of CFT Legumine on multi-aged tadpoles of the federally listed Chiricahua leopard frog Lithobates chiricahuensis, the widespread northern leopard frog L. pipiens, and the increasingly invasive American bullfrog L. catesbeianus. At the earliest Gosner stages (GS 21–25), Chiricahua leopard frogs were more sensitive to CFT Legumine (median lethal concentration [LC50] = 0.41–0.58 mg/L) than American bullfrogs (LC50 = 0.63–0.69 mg/L) and northern leopard frogs (LC50 = 0.91 and 1.17 mg/L). As tadpoles developed (i.e., increase in GS), their sensitivity to rotenone decreased. In a separate series of 48-h static nonrenewal toxicity tests, tadpoles (GS 21–25 and GS 31–36) of all three species were exposed to piscicidal concentrations of CFT Legumine (0.5, 1.0, and 2.0 mg/L) to assess postexposure effects on metamorphosis. In survivors of all three species at both life stages, the time to tail resorption was nearly doubled in comparison with that of controls. For example, mid-age (GS 31–36) Chiricahua leopard frog tadpoles required 210.7 h to complete tail resorption, whereas controls required 108.5 h. However, because tail resorption is a relatively short period in metamorphosis, the total duration of development (days from posthatch to complete metamorphosis) and the final weight did not differ in either age-group surviving nominal concentrations of 0.5-, 1.0-, and 2.0-mg/L CFT Legumine relative to controls. This research demonstrates that the CFT Legumine concentrations commonly used in field applications to remove unwanted fish could result in considerable mortality of the earliest stages of Lithobates species. In addition to acute lethality, piscicide treatments may result in delayed tail resorption, which places the tadpoles at risk by increasing
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An experimental study of crevice corrosion behaviour of 316L stainless steel in artificial seawater
Energy Technology Data Exchange (ETDEWEB)
Cai Baoping [School of Electromechanical Engineering, China University of Petroleum, Dongying, Shandong 257061 (China); Liu Yonghong, E-mail: liuyhupc@126.co [School of Electromechanical Engineering, China University of Petroleum, Dongying, Shandong 257061 (China); Tian Xiaojie; Wang Fei; Li Hang; Ji Renjie [School of Electromechanical Engineering, China University of Petroleum, Dongying, Shandong 257061 (China)
2010-10-15
The effects of applied torque on corrosion behaviour of 316L stainless steel with crevices were investigated using the cyclic potentiodynamic polarization method. Three kinds of crevices (316L-to-polytetrafluoroethylene, 316L-to-fluoroelastomeric and 316L-to-316L) were tested in artificial seawater at 50 {sup o}C. Corroded surface morphology was also investigated using scanning electron microscopy. Results indicate similar trends in crevice corrosion susceptibility with increasing applied torque. Among the three crevices, the 316L stainless steel specimen, coupled to the 316L stainless steel crevice former, is the most susceptible to crevice corrosion.
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An experimental study of crevice corrosion behaviour of 316L stainless steel in artificial seawater
International Nuclear Information System (INIS)
Cai Baoping; Liu Yonghong; Tian Xiaojie; Wang Fei; Li Hang; Ji Renjie
2010-01-01
The effects of applied torque on corrosion behaviour of 316L stainless steel with crevices were investigated using the cyclic potentiodynamic polarization method. Three kinds of crevices (316L-to-polytetrafluoroethylene, 316L-to-fluoroelastomeric and 316L-to-316L) were tested in artificial seawater at 50 o C. Corroded surface morphology was also investigated using scanning electron microscopy. Results indicate similar trends in crevice corrosion susceptibility with increasing applied torque. Among the three crevices, the 316L stainless steel specimen, coupled to the 316L stainless steel crevice former, is the most susceptible to crevice corrosion.
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Crystalline-to-amorphous phase transformation in mechanically alloyed Fe50W50 powders
International Nuclear Information System (INIS)
Sherif El-Eskandarany, M.S.; Sumiyama, K.; Suzuki, K.
1997-01-01
A mechanical alloying process via a ball milling technique has been applied for preparing amorphous Fe 50 W 50 alloy powders. The results have shown that during the first and second stages of milling (0 to 360 ks) W atoms emigrate to Fe lattices to form nanocrystalline b.c.c. Fe-W solid solution, with a grain size of about 7 nm in diameter. After 720 ks of the milling time, this solid solution was transformed to an amorphous Fe-W alloy coexisting with the residual fraction of the unprocessed W powders. During the last stage of milling (720 to 1,440 ks) all of this residual W powder reacts with the amorphous phase to form a homogeneous Fe 50 W 50 amorphous alloy. The crystallization temperature and the enthalpy change of crystallization of amorphous Fe 50 W 50 powders milled for 1,440 ks were measured to be 860 K and -9kJ/mol, respectively. The amorphous Fe 50 W 50 powder produced is almost paramagnetic at room temperature. The powder comprises homogeneous and smooth spheres with an average size of about 0.5 microm in diameter
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Enhancing Women's Political Fortunes in Ghana: Is a 50/50 ...
African Journals Online (AJOL)
The 50/50 Campaign as a tool for enhancing women's political participation has gained currency in recent time. Its call for equal participation of women and men in politics and public office has reinvigorated various activisms globally. This paper examines the Campaign within the context of Ghanaian women's political ...
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Ruffinengo, Sergio; Eguaras, Martin; Floris, Ignazio; Faverin, Claudia; Bailac, Pedro; Ponzi, Marta
2005-06-01
The repellent and acaricidal effects of some essential oils from the most typical wild plant species of northern Patagonia, Argentina, on Varroa destructor Anderson & Trueman were evaluated using a complete exposure test. Honey bees, Apis mellifera L., and mites (five specimens of each per dish) were introduced in petri dishes having different oil concentrations (from 0.1 to 25 micro per cage). Survival of bees and mites was registered after 24, 48, and 72 h. An attraction/repellence test was performed using a wax tube impregnated with essential oil and another tube containing wax only. The lowest LD50 values for mites were registered for Acantholippia seriphioides (A. Gray) Mold. (1.27 microl per cage) and Schinus molle L. (2.65 microl per cage) after 24 h, and for Wedelia glauca (Ortega) O. Hoffm. ex Hicken (0.59 microl per cage) and A. seriphioides (1.09 microl per cage) after 72 h of treatment. The oil with the highest selectivity ratio (A. mellifera LD50/V. destructor LD50) was the one extracted from S. molle (>16). Oils of Lippia junelliana (Mold.) Troncoso, Minthostachys mollis (HBK) Grieseb., and Lippia turbinata Grieseb. mixed with wax had repellent properties. None of the oils tested had attractive effects on Varroa mites.
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Pidutti, P; Federici, F; Brandi, J; Manna, L; Rizzi, E; Marini, U; Cecconi, D
2018-02-01
The aim of this study was to investigate the antimicrobial potential of proteins secreted by a new strain of Lactobacillus salivarius. The secretome of L. salivarius SGL 03 strain was analysed by gel-assisted fractionation and MS/MS to identify low-molecular-mass proteins. This strategy allowed us to identify 10 secreted proteins. Then, a combination of heterologous expression and agar well diffusion was used to characterize them as to their antimicrobial activity, mechanisms of action and stability. Our findings indicate that L27 and L30 proteins of the 50S ribosomal subunit have antimicrobial activity against Streptococcus pyogenes, Streptococcus uberis and Enterococcus faecium. In addition, both proteins are bactericidal against S. pyogenes and maintain their antimicrobial activity after different protease treatments, at acidic pH, after heat treatment, and if stored in a refrigerated ambient at least at 4°C. The overall results demonstrated that the L27 and L30 ribosomal proteins are of interest as new antimicrobial molecules to prevent the growth of S. pyogenes, S. uberis and E. faecium. Our results provide the first insight into the extra-ribosomal activity of L27 and L30 secreted proteins of L. salivarius. This study demonstrated the capacity of L. salivarius SGL 03 to produce antimicrobial molecules and suggested this strain as a promising probiotic candidate. © 2017 The Society for Applied Microbiology.
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Fumigant activity of plant essential oil from Armoracia rusticana (L ...
African Journals Online (AJOL)
L.), was assessed against Plodia interpunctella (Hübner) and Sitophilus zeamais Motschulsky. A. rusticana oil was active against different life stages of P. interpunctella and adults of S. zeamais. The LC50 value for adults was the lowest and ...
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Effet du taux d'incorporation de la farine de patate douce crue dans l ...
African Journals Online (AJOL)
SARAH
31 juil. 2015 ... jusqu'à 50% dans l'alimentation de la volaille avec de très bons résultats. Par contre, selon Maphosa et al. (2003) l'incorporation de la farine de patate douce dans l'aliment des poulets de chair a un effet plutôt dépressif sur les performances de croissance. La principale raison évoquée pour expliquer ces ...
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The determination of chromium-50 in human blood and its utilization for blood volume measurements
International Nuclear Information System (INIS)
Zeisler, R.; Young, I.
1986-01-01
Possible relationships between insufficient blood volume increases during pregnancy and infant mortality could be established with an adequate measurement procedure. An accurate and precise technique for blood volume measurements has been found in the isotope dilution technique using chromium-51 as a label for red blood cells. However, in a study involving pregnant women, only stable isotopes can be used for labeling. Stable chromium-50 can be determined in total blood samples before and after dilution experiments by neutron activation analysis (NAA) or mass spectrometry. However, both techniques may be affected by insufficient sensitivity and contamination problems at the inherently low natural chromium concentrations to be measured in the blood. NAA procedures involving irradiations with highly thermalized neutrons at a fluence rate of 2x10 13 n/cm 2 xs and low background gamma spectrometry are applied to the analysis of total blood. Natural levels of chromium-50 in human and animal blood have been found to be <0.1 ng/mL; i.e., total chromium levels of <3 ng/mL. Based on the NAA procedure, a new approach to the blood volume measurement via chromium-50 isotope dilution has been developed which utilizes the ratio of the induced activities of chromium-51 to the iron-59 in three blood samples taken from each individual, namely blank, labeled and diluted labeled blood. (author)
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Directory of Open Access Journals (Sweden)
Carlos R. M. da Silva Filho
Full Text Available A cúrcuma é o rizoma limpo, em boas condições, seco e moído da Curcuma longa L., uma planta herbácea da família Zingiberaceae. Visando novas alternativas para o controle da esquistossomose, os extratos de Curcuma longa L. foram testados para a avaliação da atividade moluscicida contra caramujos adultos da espécie Biomphalaria glabrata, e toxicidade (ensaio de letalidade com Artemia salina. A oleoresina e o óleo essencial de cúrcuma foram ativos contra Artemia salina (CL50 = 80,43 e CL50 = 319,82 μg/mL, respectivamente e também ativos contra os indivíduos adultos de Biomphalaria glabrata (CL50 = 58,3 e CL50 = 46,73 μg/mL, respectivamente. A partir dos resultados obtidos pôde ser concluído que ambos os extratos podem constituir uma alternativa no controle da população desses caramujos e na redução da esquistossomose.
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International Nuclear Information System (INIS)
Bouchard, A.; Sanz, N.; Botvinick, E.H.; Phillips, N.; Heilbron, D.; Byrd, B.F. III; Karam, J.H.; Schiller, N.B.
1989-01-01
To further the understanding of diabetic heart disease, we tested the hypothesis that an asymptomatic group of normotensive diabetic patients between 20 and 50 years old had a restrictive cardiomyopathy independent of clinically significant coronary artery disease. Quantitative two-dimensional echocardiography and stress myocardial perfusion scintigraphy were performed to detect and characterize the cardiac abnormalities in this study group comprising 88 patients with rigorously classified diabetes and 65 volunteer control subjects. Diabetic patients were shown to have a mildly reduced left ventricular end-diastolic volume index: 50.1 +/- 8.2 and 52.1 +/- 14.7 mL/m2 for patients with type I and type II diabetes, respectively, versus 58.9 +/- 11.7 mL/m2 for control subjects. The left ventricular diastolic filling was also impaired in diabetic patients as reflected by a lower atrial emptying index: 0.73 +/- 0.24 and 0.76 +/- 0.3 for type I and type II diabetics, respectively, compared with 1.14 +/- 0.24 for control subjects. Exercise tolerance was normal in subjects with type I diabetes and slightly reduced in subjects with type II diabetes. Only one patient developed regional ischemia on thallium exercise testing. Using a comprehensive, noninvasive approach, we have shown that asymptomatic normotensive patients with type I or type II diabetes who were between 20 and 50 years old had a restrictive cardiomyopathy characterized by mildly reduced left ventricular end-diastolic volume and altered left ventricular compliance independent of critical coronary artery disease
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Sui, Liying; Liu, Liangsen; Deng, Yuangao
2014-11-01
Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of biological functions. Ten red colonies were isolated from brine water in a saltern crystallizer pond of the Hangu Saltworks, China. 16S rRNA gene sequence analysis showed that the colonies belonged to the extremely halophilic archaea genera Halobacterium and Halorubrum. Two representative strains, Halobacterium strain SP-2 and Halorubrum strain SP-4, were selected for further study on the phenotypic characteristics and effects of salinity and pH on accumulation and composition of pigments in their cells. The archaeal strains were isolated and grown in a culture medium prepared by dissolving yeast extract (10 g/L) and acid-hydrolyzed casein (7.5 g/L) into brine water obtained from a local salt pond. Their optimum salinity and pH for growth were 250 and 7, respectively, although pigment accumulation (OD490 / mL broth) was highest at pH 8. In addition, at 150-300 salinity, increasing salinity resulted in decreasing pigment accumulation. Analysis of the UV-Vis spectrum, TLC and HLPC chromatograms showed that C50 carotenoid bacterioruberin is the major pigment in both strains.
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Directory of Open Access Journals (Sweden)
B Rasoulian
2016-09-01
Full Text Available Introduction: Cisplatin is a widely used anti-cancer drug, which its application is limited by nephrotoxicity. In this study, the effect of pretreatment with different l-arginine doses on Cisplatin-induced renal functional injury was investigated. Methods: 63 male rats were divided into 7 groups: In groups 3, 4, 5 and 6, 60 min before the Cisplatin injection (5mg/kg; L-Arginine with doses of 50,100,200 or 400mg/kg was injected, respectively. In group7, normal saline was injected before Cisplatin administration. In groups 1 and 2, normal saline was injected instead of Cisplatin. In group 2, 60min before normal saline injection, 400mg/kg L-Arginine was administered and in group1, instead of L-arginine, normal saline was injected too. Injections were intraperitoneal. 72h after Cisplatin injection, blood sampling and plasma separation were done. Urine sample was collected 24 hours before blood sampling by metabolic cage. The mean of plasma urea and creatinine levels and creatinine clearance (ml/day.kg and fractional excretion of Na (FENa, % were compared among different groups as renal functional parameters. Results: In comparison to group 7, L-arginine injection in a dose of 400mg/kg led to significant amelioration of all parameters. 200 mg/kg L-arginine administration led to significant decrease in plasma urea level and FENa. 100mg/kg L-arginine caused significant improvement in fractional excretion of sodium. L-arginine injection with 50mg/kg dose, significantly ameliorate all renal function tests instead of creatinine clearance. Conclusion: Pretreatment with L-arginine administration with 400 or 50 mg/kg doses, respectively, had the highest effect on reducing Cisplatin-induced nephropathy. L-arginine injection with intermediate doses i.e. 200 or 100 mg/kg had less effect in reducing Cisplatin-induced nephropathy and it needs more investigations.
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Directory of Open Access Journals (Sweden)
Janaína Fernandes de Medeiros Burkert
2012-12-01
Full Text Available A procura por alimentos funcionais, como leites fermentados com culturas microbianas probióticas, aumentou o interesse em pesquisas para manter estes micro-organismos viáveis no produto. Neste sentido, o objetivo deste trabalho foi formular um leite fermentado sabor morango agregado de benefícios potencialmente prebióticos e probióticos, apresentando características sensoriais adequadas. Um planejamento fatorial 2³ com ponto central foi realizado para otimizar a saborização do produto, avaliando a adição de sacarose (50, 85 e 120 g.L-1, corante natural carmim cochonilha (0,5; 1,0 e 1,5 g.L-1 e aroma natural de morango (0,10; 0,25 e 0,40 g.L-1. Diferentes concentrações da cultura Bio Rich (L. acidophilus, Bifidobacterium e S. thermophilus foram testadas (1,00; 0,50 e 0,33 g.L-1, ordenando-se sensorialmente conforme a preferência. Concentrações do xarope de fruto-oligossacarídeos (50 e 100 g.L-1 foram avaliadas por meio de aceitação sensorial e análises microbiológicas. Um leite fermentado sabor morango utilizando, em g.L-1, 0,33 de cultura, 120 de sacarose, 1,5 de corante, 0,4 de aroma e 100 de xarope de fruto-oligossacarídeos, foi desenvolvido. O incremento da concentração de prebiótico influenciou positivamente na preferência do produto, apresentando índice de aceitação de 88%; microbiologicamente, aumentou a contagem de L. acidophilus e Bifidobacterium, sendo 1,7 × 10(7 e 4,8 × 10(6 UFC.mL-1, respectivamente, com 100 g.L-1 de prebiótico.The demand for functional foods, including milk fermented with probiotic microbial cultures, has increased the interest in research to maintain these microorganisms viable in the product. Thus the objective of this work was to formulate strawberry flavoured fermented milk with added potentially beneficial prebiotics and probiotics, and with suitable sensory characteristics. A 2³ experimental design was used to optimize the product flavour, evaluating the addition of sucrose (50
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A Chemical Investigation of the Leaves of Morus alba L.
Chen, Xiao-Yan; Zhang, Ting; Wang, Xin; Hamann, Mark T; Kang, Jie; Yu, De-Quan; Chen, Ruo-Yun
2018-04-26
The leaves of Morus alba L. are an important herbal medicine in Asia. The systematic isolation of the metabolites of the leaves of Morus alba L. was achieved using a combination of liquid chromatography techniques. The structures were elucidated by spectroscopic data analysis and the absolute configuration was determined based on electronic circular dichroism (ECD) spectroscopic data and hydrolysis experiments. Their biological activity was evaluated using different biological assays, such as the assessment of their capacity to inhibit the aldose reductase enzyme; the determination of their cytotoxic activity and the evaluation of their neuroprotective effects against the deprivation of serum or against the presence of nicouline. Chemical investigation of the leaves of Morus alba L. resulted in four new structures 1 ⁻ 4 and a known molecule 5 . Compounds 2 and 5 inhibited aldose reductase with IC 50 values of 4.33 μM and 6.0 μM compared with the potent AR inhibitor epalrestat (IC 50 1.88 × 10 −3 μM). Pretreatment with compound 3 decreased PC12 cell apoptosis subsequent serum deprivation condition and pretreatment with compound 5 decreased nicouline-induced PC12 cell apoptosis as compared with control cells ( p < 0.001).
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Low-Mass Dark Matter Search with the DarkSide-50 Experiment
Energy Technology Data Exchange (ETDEWEB)
Agnes, P.; et al.
2018-02-20
We present the results of a search for dark matter WIMPs in the mass range below 20 GeV/c^2 using a target of low-radioactivity argon. The data were obtained using the DarkSide-50 apparatus at Laboratori Nazionali del Gran Sasso (LNGS). The analysis is based on the ionization signal, for which the DarkSide-50 time projection chamber is fully efficient at 0.1 keVee. The observed rate in the detector at 0.5 keVee is about 1.5 events/keVee/kg/day and is almost entirely accounted for by known background sources. We obtain a 90% C.L. exclusion limit above 1.8 GeV/c^2 for the spin-independent cross section of dark matter WIMPs on nucleons, extending the exclusion region for dark matter below previous limits in the range 1.8-6 GeV/c^2.
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Sederel, Willem L.; Bantjes, Adriaan; Feijen, Jan; Anderson, James M.
1980-01-01
The solid-state conformation of copolymers of ß-benzyl-L-aspartate [L-Asp(OBzl)] with L-leucine (L-Leu), L-alanine (L-Ala), L-valine (L-Val), γ-benzyl-L-glutamate [L-Glu(OBzl)], or ε-carbobenzoxy-L-lysine (Cbz-L-Lys) has been studied by ir spectroscopy and circular dichroism (CD). The ir spectra in
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The Lattice for the 50-50 GeV Muon Collider
International Nuclear Information System (INIS)
Ng, K.-Y.; Trbojevic, D.
1998-02-01
The lattice design of the 50-50 Gev muon collider is presented. Due to the short lifetime of the 50 GeV muons, the ring needs to be as small as possible. The 4 cm low betas in both planes lead to high betatron functions at the focusing quadrupoles and hence large chromaticities, which must be corrected locally. In order to maintain a low rf voltage of around 10 MV, the momentum-compaction factor must be kept to less than 10 -2 , and therefore the flexible momentum-compaction modules are used in the arcs. The dynamical aperture is larger than 6 to 7 rms beam size for ±5 rms momentum offset. Comments are given and modifications are suggested
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Cytotoxicity difference of 316L stainless steel and titanium reconstruction plate
Directory of Open Access Journals (Sweden)
Ni Putu Mira Sumarta
2011-03-01
Full Text Available Background: Pure titanium is the most biocompatible material today and used as a gold standard for metallic implants. However, stainless steel is still being used as implants because of its strength, ductility, lower price, corrosion resistant and biocompatibility. Purpose: This study was done to revealed the cytotoxicity difference between reconstruction plate made of 316L stainless steel and of commercially pure (CP titanium in baby hamster kidney-21 (BHK-21 fibroblast culture through MTT assay. Methods: Eight samples were prepared from reconstruction plates made of stainless steel type 316L grade 2 (Coen’s reconstruction plate® that had been cut into cylindrical form of 2 mm in diameter and 3 mm long. The other one were made of CP titanium (STEMA Gmbh® of 2 mm in diameter and 2,2 mm long; and had been cleaned with silica paper and ultrasonic cleaner, and sterilized in autoclave at 121° C for 20 minutes.9 Both samples were bathed into microplate well containing 50 μl of fibroblast cells with 2 x 105 density in Rosewell Park Memorial Institute-1640 (RPMI-1640 media, spinned at 30 rpm for 5 minutes. Microplate well was incubated for 24 and 48 hours in 37° C. After 24 hours, each well that will be read at 24 hour were added with 50 μl solution containing 5mg/ml MTT reagent in phosphate buffer saline (PBS solutions, then reincubated for 4 hours in CO2 10% and 37° C. Colorometric assay with MTT was used to evaluate viability of the cells population after 24 hours. Then, each well were added with 50 μl dimethyl sulfoxide (DMSO and reincubated for 5 minutes in 37° C. the wells were read using Elisa reader in 620 nm wave length. Same steps were done for the wells that will be read in 48 hours. Each data were tabulated and analyzed using independent T-test with significance of 5%. Results: This study showed that the percentage of living fibroblast after exposure to 316L stainless steel reconstruction plate was 61.58% after 24 hours and 62
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Directory of Open Access Journals (Sweden)
Angélica de Fátima de Assunção Braga
2009-06-01
Full Text Available JUSTIFICATIVA E OBJETIVOS: A bupivacaína racêmica a 0,5% associada a opioides por via peridural constitui técnica anestésica utilizada em cesariana, entretanto sua toxicidade é questionada. A bupivacaína com excesso enantiomérico de 50% apresenta menor cárdio e neurotoxicidade. Avaliou-se a eficácia da bupivacaína racêmica e da bupivacaína com excesso enantiomérico de 50% a 0,5%, associadas ao sufentanil, por via peridural, em gestantes submetidas à cesariana. MÉTODO: Cinquenta gestantes a termo, submetidas à cesariana eletiva, sob bloqueio peridural, distribuídas em dois grupos, de acordo com o anestésico local empregado: Grupo I - bupivacaína racêmica a 0,5% com vasoconstritor; Grupo II - bupivacaína com excesso enantiomérico de 50% (S75-R25 a 0,5% com vasoconstritor. Nos dois grupos o anestésico local (100 mg foi associado ao sufentanil (20 µg e o volume total empregado da solução foi de 24 mL. Avaliaram-se: latência do bloqueio sensitivo; nível máximo do bloqueio sensitivo; grau do bloqueio motor; tempo para regressão do bloqueio motor; duração da analgesia; efeitos colaterais maternos e repercussões neonatais. RESULTADOS: A latência, o nível máximo do bloqueio sensitivo, o grau do bloqueio motor e a duração da analgesia foram semelhantes nos dois grupos; o tempo para regressão do bloqueio motor foi significativamente menor no Grupo II. Os efeitos colaterais ocorreram com frequência semelhante em ambos os grupos. Ausência de alterações cardiocirculatórias maternas e repercussões neonatais. CONCLUSÕES: A bupivacaína racêmica e a bupivacaína com excesso enantiomérico de 50%, por via peridural, proporcionam anestesia adequada para realização de cesariana. A bupivacaína com excesso enantiomérico de 50% constitui alternativa promissora para esse tipo de procedimento, por apresentar menor tempo para regressão do bloqueio motor, desejável na paciente obstétrica.JUSTIFICATIVA Y OBJETIVOS: La
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Indrawati, T.; Syahrin, A.; Irpan
2017-07-01
Caesalpinia sappan L. (Cs L) contains of essential oils, saponin, brazilin, brazilein, alkaloids, flavonoids and tannins that have a function as cationic natural dyes. The aim of this research was to prepare the ethanol extract of Cs L wood and to prepare demi-permanent and semi-permanent of hair dye gels by using Carbomer of 2 % and 1.5 % as gelling agent and Cs L extract as cationic dyes. The Extract of Cs L was macerated by using ethanol of 96 % as the solvent, and then thickened. Three formula of demi-permanent hair dye gels were made by using Cs L extract of 3 %, 6% and 9 %. Three formula of semi-permanent hair dye gels were made by using Cs L extract of 2.50 %, 7.00 % and 10.50 %. Those hair dyes gels were prepared by swelling and mixing methods. All products of hair dyes gels were evaluated with organoleptic test, homogeneity test, pH test, consistency test, rheological properties test and dyeing effect test. The demi-permanent hair dye gels products had brown to brown dark black colors, pH of 5.05-5.43, homogeny, specific Cs L odor, and had pseudoplastic thixotropic flow characteristic. The semi-permanent hair dye gels products had red color pH of 6.5-6.25, homogeny, Cs L odor, and have pseudoplastic thixotropic flow characteristics. The optimum formula of demi-permanent was formula gel that contained of 6 % extract of Cs L and the optimum formula of permanent hair dyes gel was formula that contained of 10.50 % extract of Cs L.
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van der Meulen, Sjoerd B; de Jong, Anne; Kok, Jan
2016-01-01
RNA sequencing has revolutionized genome-wide transcriptome analyses, and the identification of non-coding regulatory RNAs in bacteria has thus increased concurrently. Here we reveal the transcriptome map of the lactic acid bacterial paradigm Lactococcus lactis MG1363 by employing differential RNA sequencing (dRNA-seq) and a combination of manual and automated transcriptome mining. This resulted in a high-resolution genome annotation of L. lactis and the identification of 60 cis-encoded antisense RNAs (asRNAs), 186 trans-encoded putative regulatory RNAs (sRNAs) and 134 novel small ORFs. Based on the putative targets of asRNAs, a novel classification is proposed. Several transcription factor DNA binding motifs were identified in the promoter sequences of (a)sRNAs, providing insight in the interplay between lactococcal regulatory RNAs and transcription factors. The presence and lengths of 14 putative sRNAs were experimentally confirmed by differential Northern hybridization, including the abundant RNA 6S that is differentially expressed depending on the available carbon source. For another sRNA, LLMGnc_147, functional analysis revealed that it is involved in carbon uptake and metabolism. L. lactis contains 13% leaderless mRNAs (lmRNAs) that, from an analysis of overrepresentation in GO classes, seem predominantly involved in nucleotide metabolism and DNA/RNA binding. Moreover, an A-rich sequence motif immediately following the start codon was uncovered, which could provide novel insight in the translation of lmRNAs. Altogether, this first experimental genome-wide assessment of the transcriptome landscape of L. lactis and subsequent sRNA studies provide an extensive basis for the investigation of regulatory RNAs in L. lactis and related lactococcal species.
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Wu, Yan; Guo, Shan-Shan; Huang, Dong-Ye; Wang, Cheng-Fang; Wei, Jian-Yu; Li, Zhi-Hua; Sun, Jian-Sheng; Bai, Jia-Feng; Tian, Zhao-Fu; Wang, Ping-Juan; Du, Shu-Shan
2017-04-03
The contact toxicity and repellent activities of the essential oil extracted from the rhizomes of Zingiber zerumbet (L.) Smith (Zingiberaceae) was evaluated against cigarette beetles (Lasioderma serricorne). The essential oil obtained by hydrodistillation was investigated by GC-FID and GC-MS. The main constituents of the essential oil were zerumbone (40.2%), α-caryophyllene (8.6%), humulene epoxide II (7.3%), camphene (5.9%) and fenchene (4.7%). Zerumbone and its analogues totally are accounting for 60.3% of the essential oil. It was found that the essential oil possessed contact toxicity against L. serricorne adults with a LD 50 value of 48.3 µg/adult. α-Caryophyllene (LD 50 = 13.1 µg/adult) exhibited stronger contact toxicity against L. serricorne than humulene oxide (LD 50 = 31.2 µg/adult), β-caryophyllene (LD 50 = 35.5 µg/adult) and zerumbone (LD 50 = 42.4 µg/adult). Moreover, α-caryophyllene possessed strong repellent activity (Class IV and V, respectively) against the beetles at 78.63 nL/cm 2 , after 2 and 4 h treatment. The results indicate that zerumbone and its analogues might be developed into natural insecticides or repellents for control of cigarette beetles, but their bioactivities are affected by their structures.
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Utilization of bio-waste cotton ( Gossypium hirsutum L.) stalks and ...
African Journals Online (AJOL)
... three-layer particleboard containing different cotton (Gossypium hirsutum L.) stalks and underutilized paulownia (paulownia fortunie) wood particle ratios (30, 50 and 70%) using urea formaldehyde resin. Addition of cotton stalk and paulownia wood in particleboard improved mechanical properties of resulting composites ...
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Directory of Open Access Journals (Sweden)
Fábio de Almeida Vieira
2006-06-01
Full Text Available The aim of this paper was to verify the effect of different doses of gibberellic acid (GA3 (0, 250, 500, 750 and 1000 µg.L-1, of fungicides of the groups chemical benzimidazol (0, 25, 50 and 100 g.L-1 and ditiocarbamato (0, 1,25, 2,50 and 5,00 g.L-1 on seed germination. Viability of those seeds was evaluated through germination tests at 0, 15, 30 and 60 days. The experiment was carried out in greenhouse. The experimental design was fully randomized one, with five replicates per treatment. The traits evaluated were emergence and index of emergence speed. The treatment with GA3 didn't provide significant so much differences among the germination rates as well as for the emergence speed. It was verified that the use of the fungicides in smaller concentrations (25 g.L-1 of benzimidazol and 1,25 g.L-1 of ditiocarbamato promoted a better germination speed. The seeds of G. americana possess viability period relatively short, with germination absence 60 days period of storage, and it could be associated to the humidity tenors presented by the seeds in this period.
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Method of separating (125I)-L-thyroxine from mixture obtained by radioiodination
International Nuclear Information System (INIS)
Mucha, J.; Talan, P.; Dobias, M.
1982-01-01
( 125 I)-L-thyroxine is separated by gel filtration on a column from the mixture of ( 125 I)-L-thyroxine, ( 125 I)-L-3,5,3'-triiodothyronine and ( 125 I) - . The column is packed with a non-polar gel such as polydextran with particle size 25 to 100 μm. The mixture 1,2-propanediol/distilled water/concentrated (26%) aqueous ammonia solution, or 1,2-propanediol/concentrated (26%) aqueous ammonia solution is used as eluent. The concentration of the eluate containing ( 125 I)-L-thyroxine is adjusted with distilled water such as to establish a 50 vol.% concentration of 1,2-propanediol. (E.S.)
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The handling of plutonium hexafluoride (1962); Manipulation de l'hexafluorure de plutonium (1962)
Energy Technology Data Exchange (ETDEWEB)
Berard, Ph [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires
1961-11-15
The major problem posed in this work is the instability of plutonium hexafluoride. The influence of various factors on the decomposition of the fluoride has been studied: physical aspect of the walls, nature of the metal and its pretreatment, influence of the temperature. A means of detecting plutonium-239 in a metallic apparatus by {gamma}-ray counting has been developed; the sensitivity is of the order of half a milligram, but the precision is very low (about 50 per cent). Yields of over 95 per cent have been obtained for the transfer of plutonium during the preparation and sublimation of the hexafluoride. This study confirms the possibility of using plutonium hexafluoride for the extraction of plutonium from irradiated fuel elements by a dry method. (author) [French] Le probleme majeur de cette etude a ete l'instabilite de l'hexafluorure de plutonium. Nous avons etudie l'influence de divers facteurs sur la decomposition de l'hexafluorure: aspect physique des parois, nature du metal et de son pretraitement, influence de la temperature. Nous avons mis au point un mode de detection du plutonium-239 dans un appareillage metallique par comptage du rayonnement {gamma}; la sensibilite est de l'ordre du demi-milligramme, mais la precision est tres faible (50 pour cent environ). Nous avons obtenu des rendements depassant 95 pour cent dans le transfert du plutonium au cours de la fabrication et de la sublimation de l'hexafluorure. Cette etude confirme la possibilite d'utiliser l'hexafluorure de plutonium dans l'extraction du plutonium des combustibles irradies par voie seche. (auteur)
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Juturu, Veeresh; Wu, Jin Chuan
2018-03-01
Thermophilic Bacillus coagulans JI12 was used to ferment hemicellulose hydrolysate obtained by acid hydrolysis of oil palm empty fruit bunch at 50 °C and pH 6, producing 105.4 g/L of l-lactic acid with a productivity of 9.3 g/L/H by fed-batch fermentation under unsterilized conditions. Simultaneous saccharification and fermentation (SSF) was performed at pH 5.5 and 50 °C to convert both hemicellulose hydrolysate and cellulose-lignin complex in the presence of Cellic Ctec2 cellulases using yeast extract (20 g/L) as the nitrogen source, giving 114.0 g/L of l-lactic acid with a productivity of 5.7 g/L/H. The SSF was also conducted by replacing yeast extract with equal amount of dry Bakers' yeast, achieving 120.0 g/L of l-lactic acid with a productivity of 4.3 g/L/H. To the best of our knowledge, these lactic acid titers and productivities are the highest ever reported from lignocellulose hydrolysates. © 2017 International Union of Biochemistry and Molecular Biology, Inc.
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El Baroty, Gamal S.
2016-01-01
L-asparaginase (L-AsnA) is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA from Spirulina maxima (SM) were tested. SM cultures grown in Zarrouk medium containing different N2 (in NaNO3 form) concentrations (1.25, 2.50, and 5.0 g/L) for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2 concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2) showed a high AsnA enzyme activity (898 IU), total protein (405 mg/g), specific enzyme activity (2.21 IU/mg protein), and enzyme yield (51.28 IU/L) compared with those in low N2 cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production in S. maxima. PMID:27525017
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Directory of Open Access Journals (Sweden)
Hanaa H. Abd El Baky
2016-01-01
Full Text Available L-asparaginase (L-AsnA is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA from Spirulina maxima (SM were tested. SM cultures grown in Zarrouk medium containing different N2 (in NaNO3 form concentrations (1.25, 2.50, and 5.0 g/L for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2 concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2 showed a high AsnA enzyme activity (898 IU, total protein (405 mg/g, specific enzyme activity (2.21 IU/mg protein, and enzyme yield (51.28 IU/L compared with those in low N2 cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production in S. maxima.
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Preventive Effect of Zea mays L. (Purple Waxy Corn) on Experimental Diabetic Cataract
Thiraphatthanavong, Paphaphat; Wattanathorn, Jintanaporn; Muchimapura, Supaporn; Thukham-mee, Wipawee; Wannanon, Panakaporn; Tong-un, Terdthai; Suriharn, Bhalang; Lertrat, Kamol
2014-01-01
Recently, substances possessing antioxidant can prevent cataractogenesis of diabetic cataract. Therefore, this study was carried out to determine the anticataract effect of Zea mays L. (purple waxy corn), a flavonoids rich plant, in experimental diabetic cataract. Enucleated rat lenses were incubated in artificial aqueous humor containing 55 mM glucose with various concentrations of Zea mays L. (purple waxy corn) ranging between 2, 10, and 50 mg/mL at room temperature for 72 h. At the end of ...
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The antioxidant and cytotoxic activities of Sonchus oleraceus L. extracts
Yin, Jie; Kwon, Gu-Joong; Wang, Myeong-Hyeon
2007-01-01
This study investigated in vitro antioxidant activity of Sonchus oleraceus L. by extraction solvent, which were examined by reducing power, hydroxyl radical-scavenging activity(HRSA) and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assays. 70% MeOH extract had the greatest reducing power while EtOH extract had the greatest HRSA. The antioxidant activity of S. oleraceus extracts was concentration dependent and its IC50 values ranged from 47.1 to 210.5 ?g/ml and IC50 of 70% MeOH, bo...
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Use of 50% Dextrose as the Distension Medium During Cystoscopy for Visualization of Ureteric Jets.
Narasimhulu, Deepa M; Prabakar, Cheruba; Tang, Nancy; Bral, Pedram
2016-01-01
Indigotindisulfonate sodium has been used to color the urine and thereby improve the visualization of ureteric jets during intraoperative cystoscopy. After indigotindisulfonate sodium became unavailable, there has been an ongoing search for an alternate agent to improve visualization of the jets. We used 50% dextrose, which is more viscous than urine, as the distension medium during cystoscopy so that the ureteric efflux is seen as a jet of contrasting viscosity. We instilled 100 mL of 50% dextrose into the bladder through an indwelling catheter, which is then removed and cystoscopy is performed as usual. We observed jets of contrasting viscosity in every patient in whom 50% dextrose was used as compared with coloring agents in which the jet is not always colored at the time of cystoscopy. Visualization of the other structures in the bladder and the bladder wall itself is not altered by 50% dextrose, although the volume of 50% dextrose that we typically use may not provide adequate distension for a complete assessment of the bladder. If additional distension is necessary, normal saline may be used in addition to the 50% dextrose once the ureteric jets have been assessed. Fifty percent dextrose is an effective alternative to indigotindisulfonate sodium for visualization of ureteric jets during cystoscopy.
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Comparative Study of API 5L X60 and ASTM 572 Gr50 Steel Exposed to Crude Oil and Seawater
Directory of Open Access Journals (Sweden)
Marcy Viviana Chiquillo Márquez
2018-04-01
Full Text Available In the petroleum industry, the biphasic conditions in storage and separation tanks allow that the material to remain exposed to two different environments, causing its deterioration. In this article, an evaluation is made of the corrosive behavior and Vickers microhardness (HV of two high strength low alloy (HSLA steels and how their surfaces are characterized. The ASTM 572 Gr50 steel showed a lower corrosion rate in all systems after being immersed for 720 and 1440 hours. Characterizing the surface by means of Scanning Electron Microscopy (SEM showed uniform and localized corrosion for the both steels, and revealed that the ASTM 572 Gr50 steel shows pitting corrosion in crude oil systems. The electrochemical results revealed that the corrosion potential of API X60 steel was more negative; however the ASTM 572 Gr50 steel had a higher current density and a lower polarization resistance when immersed in an oil/seawater mixture. It also observed that, after being immersed in the corrosive fluids, the microstructures of the steels were not modified and variations in their microhardness (HV were minute.
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[Update on L-asparaginase treatment in paediatrics].
Moscardó Guilleme, C; Fernández Delgado, R; Sevilla Navarro, J; Astigarraga Aguirre, I; Rives Solà, S; Sánchez de Toledo Codina, J; Fuster Soler, J L; Parra Ramirez, L; Molina Garicaño, J; González Martínez, B; Madero López, L
2013-11-01
L-asparaginase (L-ASP) is one of the cornerstones of the treatment of acute lymphoblastic leukemia and non-Hodgkin lymphoma. It is an enzyme of bacterial origin capable of transforming L-asparagine to aspartic acid. The extracellular depletion of L-asparagine inhibits protein synthesis in lymphoblasts, inducing their apoptosis. Numerous studies have demonstrated that treatment with L-ASP improves survival of patients, but there are clear differences in the characteristics of the three currently available formulations. This article reviews the dosage, activity and side effects of the two L-ASP derived from Escherichia coli (native and pegylated), and the one derived from Erwinia chrysanthemi (Erwinia ASP). Despite its indisputable indication over the past50 years, there are still many points of contention, and its use is still marked by the side effects of the inhibition of protein synthesis. The short half-life of native forms, and the most frequently used parenteral administration by intramuscular injections, affects the quality of life of the patients. Therefore, recent studies claim to evaluate alternatives, such as the formulation of longer half-life pegylated L-ASP, and the use of intravenous formulations. There are encouraging results to date with both preparations. Still, further studies are needed to establish which should be the formulation and frontline indicated route of administration, optimal dosing, and management of adverse effects. Copyright © 2013 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.
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Directory of Open Access Journals (Sweden)
Nooshin Zandi-Sohani
2012-12-01
Full Text Available Lantana camara L. is a widespread plant species mostly native to subtropical and tropical regions of the world. In this study, insecticidal and repellent activities of L. camara essential oil were evaluated against Callosobruchus maculatus (Fabricius (Col: Bruchidae. Analysis of chemical composition by gas chromatography/mass spectrometry (GC/MS showed high amounts of sesquiterpenes, mainly α-humelene (23.3% and cis-caryophyllene (16.2%. The results showed that the essential oil of L. camara has strong repellent activity against adults of C. maculatus at all tested concentrations. After 2 and 4 h, 97.4 and 100% repellency was seen at highest concentrations of 0.4 μL cm-2, respectively. Moreover, the oil was found to be toxic to adults when applied by fumigation. Responses varied with the gender of insect and exposure time. The LC50 values were 282.7 and 187.9 μL L-1 for females and males, respectively. An increase in the exposure time from 3 to 24 h caused increasing in mortality from 23.6 to 100% in males and from 14.1 to 97.1% in females, at highest concentration (1160 μL L-1. According to these results, L. camara essential oil may be useful as an alternative for bean protection against C. maculatus.Lantana camara L. es una especie vegetal nativa de las regiones subtropicales y tropicales del mundo. En este estudio se evaluaron las actividades insecticida y repelente del aceite esencial de L. camara contra Callosobruchus maculatus (Fabricius. El análisis de la composición volátil de este aceite esencial mediante cromatografía de gas/ espectrometría de masa (GC/MS demostró la presencia de elevadas cantidades de sesquiterpenos, principalmente α-humuleno (23.3% y ci's-cariofileno (16.2%. Los resultados obtenidos demostraron que el aceite esencial de L. camara tiene una elevada actividad repelente contra los adultos de C. maculatus a todas las concentraciones ensayadas. Después de 2 y 4 h la concentración de 0.4 μL cm-2 causó 97
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Heritability and correlates of maize yield ( Zea mays L .) under ...
African Journals Online (AJOL)
Heritability and correlates of maize yield ( Zea mays L .) under varying drought conditions. ... Nigeria Agricultural Journal ... Correlation analysis revealed that days to 50% tasseling and silking under non-stress, ASI and leaf senescence under severe stress exhibited negative and significant correlations with grain yield.
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Magnetic force microscopy and simulation studies on Co 50 Fe 50 ...
Indian Academy of Sciences (India)
We studied the magnetization reversal mechanism of single-layered Co50Fe50 nanomagnets by measuring the magnetization reversal and using the micromagnetic simulations. The magnetization reversal strongly depends on the thickness of the nanomagnets. In the remanent state, the magnetic force microscopy studies ...
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HLBT-100: a highly potent anti-cancer flavanone from Tillandsia recurvata (L.) L.
Lowe, Henry I C; Toyang, Ngeh J; Watson, Charah T; Ayeah, Kenneth N; Bryant, Joseph
2017-01-01
The incidence and mortalities from cancers remain on the rise worldwide. Despite significant efforts to discover and develop novel anticancer agents, many cancers remain in the unmet need category. As such, efforts to discover and develop new and more effective and less toxic agents against cancer remain a top global priority. Our drug discovery approach is natural products based with a focus on plants. Tillandsia recurvata (L.) L. is one of the plants selected by our research team for further studies based on previous bioactivity findings on the anticancer activity of this plant. The plant biomass was extracted using supercritical fluid extraction technology with CO 2 as the mobile phase. Bioactivity guided isolation was achieved by use of chromatographic technics combined with anti-proliferative assays to determine the active fraction and subsequently the pure compound. Following in house screening, the identified molecule was submitted to the US National Cancer Institute for screening on the NCI60 cell line panel using standard protocols. Effect of HLBT-100 on apoptosis, caspase 3/7, cell cycle and DNA fragmentation were assessed using standard protocols. Antiangiogenic activity was carried out using the ex vivo rat aortic ring assay. A flavonoid of the flavanone class was isolated from T. recurvata (L.) L. with potent anticancer activity. The molecule was code named as HLBT-100 (also referred to as HLBT-001). The compound inhibited brain cancer (U87 MG), breast cancer (MDA-MB231), leukemia (MV4-11), melanoma (A375), and neuroblastoma (IMR-32) with IC 50 concentrations of 0.054, 0.030, 0.024, 0.003 and 0.05 µM, respectively. The molecule also exhibited broad anticancer activity in the NCI60 panel inhibiting especially hematological, colon, CNS, melanoma, ovarian, breast and prostate cancers. Twenty-three of the NCI60 cell lines were inhibited with GI 50 values <0.100 µM. In terms of potential mechanisms of action, the molecule demonstrated effect on the
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Physiological responses and tolerance of kenaf (Hibiscus cannabinus L.) exposed to chromium.
Ding, Han; Wang, Guodong; Lou, Lili; Lv, Jinyin
2016-11-01
Selection of kenaf species with chromium (Cr) tolerance and exploring the physiological mechanisms involved in Cr tolerance are crucial for application of these species to phyto-remediation. In the present study, a hydroponic experiment was conducted to investigate the variation in two kenaf cultivars, K39-2 and Zhe50-3 under Cr stress. At the same Cr concentration, the tolerance index (TI) of K39-2 was higher than that of Zhe50-3, indicating that K39-2 may be more tolerant to Cr than Zhe50-3. It was also observed that high concentration of chromium was accumulated both in the shoots and the roots of Hibiscus cannabinus L. The leaves of K39-2 accumulated 4760.28mgkg(-1) of dry weight under 1.50mM Cr stress, and the roots accumulated 11,958.33mgkg(-1). Physiological response shows that the antioxidant enzymes' superoxide dismutase (SOD), catalase activity (CAT) and peroxidase (POD) activities increased in the leaves and decreased in roots of the Cr-stressed plants nearly compared to the control. Moreover, the variation of antioxidant enzymes activities indicated Zhe50-3 was more vulnerable than K39-2, and the contents of the non-protein thiol pool (GSH, NPT and PCs) were higher in K39-2 than Zhe50-3 with the increased Cr concentration. Based on the observations above, it can be concluded that the well-coordinated physiological changes confer a greater Cr tolerance to K39-2 than Zhe50-3 under Cr exposure, and Hibiscus cannabinus L. has a great accumulation capacity for chromium. Copyright © 2016 Elsevier Inc. All rights reserved.
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Audiitorfirmade TOP 50 aastal 2000
2001-01-01
Audiitorfirmade käibe TOP 50, käibe kasvu TOP 25, käibe languse TOP 15, kasumi TOP 50, kasumi kasvu TOP 10, kasumi languse TOP 10, audiitorfirmade finantsnäitajad. Rentaabluse TOP 50, varade tootlikkuse TOP 50
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Genetic variability in L1 and L2 genes of HPV-16 and HPV-58 in Southwest China.
Directory of Open Access Journals (Sweden)
Yaofei Yue
Full Text Available HPV account for most of the incidence of cervical cancer. Approximately 90% of anal cancers and a smaller subset (<50% of other cancers (oropharyngeal, penile, vaginal, vulvar are also attributed to HPV. The L1 protein comprising HPV vaccine formulations elicits high-titre neutralizing antibodies and confers type restricted protection. The L2 protein is a promising candidate for a broadly protective HPV vaccine. In our previous study, we found the most prevalent high-risk HPV infectious serotypes were HPV-16 and HPV-58 among women of Southwest China. To explore gene polymorphisms and intratypic variations of HPV-16 and HPV-58 L1/L2 genes originating in Southwest China, HPV-16 (L1: n = 31, L2: n = 28 and HPV-58 (L1: n = 21, L2: n = 21 L1/L2 genes were sequenced and compared to others described and submitted to GenBank. Phylogenetic trees were then constructed by Neighbor-Joining and the Kimura 2-parameters methods (MEGA software, followed by an analysis of the diversity of secondary structure. Then selection pressures acting on the L1/L2 genes were estimated by PAML software. Twenty-nine single nucleotide changes were observed in HPV-16 L1 sequences with 16/29 non-synonymous mutations and 13/29 synonymous mutations (six in alpha helix and two in beta turns. Seventeen single nucleotide changes were observed in HPV-16 L2 sequences with 8/17 non-synonymous mutations (one in beta turn and 9/17 synonymous mutations. Twenty-four single nucleotide changes were observed in HPV-58 L1 sequences with 10/24 non-synonymous mutations and 14/24 synonymous mutations (eight in alpha helix and four in beta turn. Seven single nucleotide changes were observed in HPV-58 L2 sequences with 4/7 non-synonymous mutations and 3/7 synonymous mutations. The result of selective pressure analysis showed that most of these mutations were of positive selection. This study may help understand the intrinsic geographical relatedness and biological differences of HPV-16/HPV-58 and
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IKEA:s gråa hål : Hur IKEA kan få 50+ att handla mer möbler
Fredriksson, Patrik; Persson, Sebastian
2008-01-01
Syfte: Uppsatsen syfte är att beskriva och analysera varför IKEA-besökare i Karlstad, som tillhör kundgruppen 50+, väljer att inte handla möbler i samma utsträckning som de yngre besökarna. Metod: Uppsatsens undersökning grundas på en kvalitativ och en kvantitativ metod. Den kvalitativa metoden består av 20 öppna intervjuer med människor i kundgruppen 50+. Den kvantitativa metoden kompletterar den kvalitativa och består av frågeformulär som samtliga intervjuobjekt fick fylla i efter intervj...
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Validation of a microfluorimetric method for quantitation of L-Histidine in peripheral blood
International Nuclear Information System (INIS)
Contreras Roura, Jiovanna; Hernandez Cuervo, Orietta; Alonso Jimenez, Elsa
2008-01-01
Histidinemia is a rare inherited metabolic disorder characterized by deficient histidase enzyme, which results in elevated histidine levels in blood, urine and cerebrospinal fluid and, sometimes, hyperalaninemia. Histidinemia clinical picture varies from mental retardation and speech disorders to absence of any symptoms. This disease can be diagnosed by histidine-level-in-blood-quantitating tests using different analytical methods such as spectrofluorimetry and High Pressure Liquid Chromatography. An analytical method using SUMA Technology was developed and validated at our laboratory to determine L-Histidine in blood: serum and dried blood spot (adult and neonatal) so as to use it in Histidinemia screening in children with speech disorders. This paper presents selectivity, linearity, accuracy and precision data. The calibration curve showed linearity ranging 1-12 mg/dL or 64.5-774 μM, and correlation coefficient (r) and determination coefficient (r2) higher than 0.99 for each biological matrix studied were obtained. Accuracy (repeatability and intermediate accuracy assays) was demonstrated, variation coefficients lower than 20 % being obtained. Accuracy was assessed by determining absolute recovery percentage. Assay recoveries were 97.83 -105.50 % (serum), 93-121.50 % (adult spot dried blood) and 86.50-104.50 % (neonatal spot dried blood)
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Vargas-Ramírez, Alba L; Medina-Enríquez, Miriam M; Cordero-Rodríguez, Neira I; Ruiz-Cuello, Tatiana; Aguilar-Faisal, Leopoldo; Trujillo-Ferrara, José G; Alcántara-Farfán, Verónica; Rodríguez-Páez, Lorena
2016-07-01
N-ω-chloroacetyl-L-ornithine (NCAO) is an ornithine decarboxylase (ODC) inhibitor that is known to exert cytotoxic and antiproliferative effects on three neoplastic human cancer cell lines (HeLa, MCF-7, and HepG2). Here, we show that NCAO has antiproliferative activity in 13 cancer cell lines, of diverse tissue origin from human and mice, and in a mouse cancer model in vivo. All cell lines were sensitive to NCAO after 72 h of treatment (the EC50 ranged from 1 to 50.6 µmol/l). The Ca Ski cell line was the most sensitive (EC50=1.18±0.07 µmol/l) and MDA-MB-231 was the least sensitive (EC50=50.6±0.3 µmol/l). This ODC inhibitor showed selectivity for cancer cells, exerting almost no cytotoxic effect on the normal Vero cell line (EC50>1000 µmol/l). NCAO induced apoptosis and inhibited tumor cell migration in vitro. Furthermore, in vivo, this compound (at 50 and 100 mg/kg, daily intraperitoneal injection for 7 days) exerted potent antitumor activity against both solid and ascitic tumors in a mouse model using the myeloma (Ag8) cell line. At these same two doses, the toxicological evaluation showed that NCAO has no obvious systemic toxicity. The current results suggest that the antitumor activity is exerted by apoptosis related not only to a local but also a systemic cytotoxic effect exerted by NCAO on tumor cells. The applications for NCAO as an antitumor agent may be extensive; however, further studies are needed to ascertain the antitumor activity on other types of tumor in vivo and to determine the precise molecular mechanism of its activity.
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50 CFR 21.50 - Depredation order for resident Canada geese nests and eggs.
2010-10-01
... geese nests and eggs. 21.50 Section 21.50 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE... and Otherwise Injurious Birds § 21.50 Depredation order for resident Canada geese nests and eggs. (a... nests and eggs, and what is its purpose? The nest and egg depredation order for resident Canada geese...
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Directory of Open Access Journals (Sweden)
Jorge Arroyo
2014-01-01
Full Text Available Introducción: Piper aduncum (matico es una especie utilizada por sus propiedades medicinales en desórdenes gastrointestinales y genitourinarios. Objetivos: Evaluar el efecto antitumoral del aceite esencial de Piper aduncum (matico in vitro en siete líneas celulares tumorales humanas y determinar la toxicidad oral en ratones. Diseño: Experimental. Institución: Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Líneas celulares tumorales humanas H460, DU-145, ME-180, K562, HT-29, MCF 7, M14, K562; fibroblastos normales de ratón 3T3 y ratones albinos machos Balb/C53. Intervenciones: Las líneas celulares fueron expuestas a cuatro concentraciones del aceite esencial de P. aduncum y 5-fluorouracilo (5-FU. Para la toxicidad oral se utilizó ratones albinos machos Balb C/53 de 40 días post destete, a cinco dosis de tratamiento, evaluándose el número de muertes en cada dosis. Principales medidas de los resultados: Porcentaje de inhibición del crecimiento celular (IC50, dosis letal 50 (DL50. Resultados: El aceite esencial mostró IC50 mayor a 250 ug/mL para las líneas celulares M-14 (r = -0,99; p 2 000 mg /kg. Conclusiones: El aceite esencial de P. aduncum no presentó efecto antitumoral in vitro para las siete líneas celulares tumorales humanas y no fue tóxico.
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Effects of L-carnitine supplementation into diets with two different fat ...
African Journals Online (AJOL)
sevilay
or without supplemental L-carnitine (0 or 50 mg/kg diet) on growth ... The cold carcass yield of quails fed the diet containing .... Temperature was kept at ...... crude fat content in breast muscle of male broilers increased significantly upon the ...