Synthesis of ellagic acid and its 4,4'-di-Ο-alky derivatives from gallic acid

OpenAIRE

Alam, Ashraful; 高口, 豊; 坪井, 貞夫

2005-01-01

Synthesis of ellagic acid and its 4,4'-di-Ο-alkyl derivatives from gallic acid is described. Ellagic acid is prepared by oxidative coupling of gallic acid with ο-chloranil. Functionalized methyl bormogallate underwent Ullmann coupling to give the biphenyl that upon lactonization resulted in the ellagic acid and its alkoxy derivatives.

Influence of rice straw-derived dissolved organic matter on lactic acid fermentation by Rhizopus oryzae.

Science.gov (United States)

Chen, Xingxuan; Wang, Xiahui; Xue, Yiyun; Zhang, Tian-Ao; Li, Yuhao; Hu, Jiajun; Tsang, Yiu Fai; Zhang, Hongsheng; Gao, Min-Tian

2018-01-31

Rice straw can be used as carbon sources for lactic acid fermentation. However, only a small amount of lactic acid is produced even though Rhizopus oryzae can consume glucose in rice straw-derived hydrolysates. This study correlated the inhibitory effect of rice straw with rice straw-derived dissolved organic matter (DOM). Lactic acid fermentations with and without DOM were conducted to investigate the effect of DOM on lactic acid fermentation by R. oryzae. Fermentation using control medium with DOM showed a similar trend to fermentation with rice straw-derived hydrolysates, showing that DOM contained the major inhibitor of rice straw. DOM assay indicated that it mainly consisted of polyphenols and polysaccharides. The addition of polyphenols and polysaccharides derived from rice straw confirmed that lactic acid fermentation was promoted by polysaccharides and significantly inhibited by polyphenols. The removal of polyphenols also improved lactic acid production. However, the loss of polysaccharides during the removal of polyphenols resulted in low glucose consumption. This study is the first to investigate the effects of rice straw-derived DOM on lactic acid fermentation by R. oryzae. The results may provide a theoretical basis for identifying inhibitors and promoters associated with lactic acid fermentation and for establishing suitable pretreatment methods. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Aristolochic acid and its derivatives as inhibitors of snake venom L-amino acid oxidase.

Science.gov (United States)

Bhattacharjee, Payel; Bera, Indrani; Chakraborty, Subhamoy; Ghoshal, Nanda; Bhattacharyya, Debasish

2017-11-01

Snake venom L-amino acid oxidase (LAAO) exerts toxicity by inducing hemorrhage, pneumorrhagia, pulmonary edema, cardiac edema, liver cell necrosis etc. Being well conserved, inhibitors of the enzyme may be synthesized using the template of the substrate, substrate binding site and features of the catalytic site of the enzyme. Previous findings showed that aristolochic acid (AA), a major constituent of Aristolochia indica, inhibits Russell's viper venom LAAO enzyme activity since, AA interacts with DNA and causes genotoxicity, derivatives of this compound were synthesized by replacing the nitro group to reduce toxicity while retaining the inhibitory potency. The interactions of AA and its derivatives with LAAO were followed by inhibition kinetics and surface plasmon resonance. Similar interactions with DNA were followed by absorption spectroscopy and atomic force microscopy. LAAO-induced cytotoxicity was evaluated by generation of reactive oxygen species (ROS), cell viability assays, confocal and epifluorescence microscopy. The hydroxyl (AA-OH) and chloro (AA-Cl) derivatives acted as inhibitors of LAAO but did not interact with DNA. The derivatives significantly reduced LAAO-induced ROS generation and cytotoxicity in human embryonic kidney (HEK 293) and hepatoma (HepG2) cell lines. Confocal images indicated that AA, AA-OH and AA-Cl interfered with the binding of LAAO to the cell membrane. AA-OH and AA-Cl significantly inhibited LAAO activity and reduced LAAO-induced cytotoxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Nitrogenous compounds stimulate glucose-derived acid production by oral Streptococcus and Actinomyces.

Science.gov (United States)

Norimatsu, Yuka; Kawashima, Junko; Takano-Yamamoto, Teruko; Takahashi, Nobuhiro

2015-09-01

Both Streptococcus and Actinomyces can produce acids from dietary sugars and are frequently found in caries lesions. In the oral cavity, nitrogenous compounds, such as peptides and amino acids, are provided continuously by saliva and crevicular gingival fluid. Given that these bacteria can also utilize nitrogen compounds for their growth, it was hypothesized that nitrogenous compounds may influence their acid production; however, no previous studies have examined this topic. Therefore, the present study aimed to assess the effects of nitrogenous compounds (tryptone and glutamate) on glucose-derived acid production by Streptococcus and Actinomyces. Acid production was evaluated using a pH-stat method under anaerobic conditions, whereas the amounts of metabolic end-products were quantified using high performance liquid chromatography. Tryptone enhanced glucose-derived acid production by up to 2.68-fold, whereas glutamate enhanced Streptococcus species only. However, neither tryptone nor glutamate altered the end-product profiles, indicating that the nitrogenous compounds stimulate the whole metabolic pathways involving in acid production from glucose, but are not actively metabolized, nor do they alter metabolic pathways. These results suggest that nitrogenous compounds in the oral cavity promote acid production by Streptococcus and Actinomyces in vivo. © 2015 The Societies and Wiley Publishing Asia Pty Ltd.

Hydroxycinnamic acid derivatives in an aquatic liverwort as possible bioindicators of enhanced UV radiation

Energy Technology Data Exchange (ETDEWEB)

Arroniz-Crespo, M.; Nunez-Olivera, E. [Universidad de La Rioja, Complejo Cientifico-Tecnologico, Avda. Madre de Dios 51, 26006 Logrono (La Rioja) (Spain); Martinez-Abaigar, J. [Universidad de La Rioja, Complejo Cientifico-Tecnologico, Avda. Madre de Dios 51, 26006 Logrono (La Rioja) (Spain)], E-mail: javier.martinez@unirioja.es

2008-01-15

We examined, under laboratory conditions, the physiological responses of the aquatic liverwort Jungermannia exsertifolia subsp. cordifolia to artificially enhanced ultraviolet (UV) radiation for 82 days, especially considering the responses of five hydroxycinnamic acid derivatives. This species lives in mountain streams, where it is exposed to low temperatures and high UV levels, and this combination is believed to increase the adverse effects of UV. Enhanced UV radiation hardly caused any change in several physiological variables indicative of vitality, such as F{sub v}/F{sub m} and chlorophylls/phaeopigments ratio (OD430/OD410). Thus, this liverwort seemed to be tolerant to UV radiation, probably due to the accumulation of three UV-absorbing hydroxycinnamic acid derivatives: p-coumaroylmalic acid, 5''-(7'',8''-dihydroxycoumaroyl)-2-caffeoylmalic acid, and 5''-(7'',8''-dihydroxy-7-O-{beta}-glucosyl-coumaroyl)-2-caffeoylmalic acid. These compounds might serve as bioindicators of enhanced UV radiation. - Several hydroxycinnamic acid derivatives of an aquatic liverwort are induced by enhanced UV radiation and might serve as bioindicators of changes in UV levels.

Folic acid derivatives for use in radioimmunoassay

International Nuclear Information System (INIS)

Ali, A.

1981-01-01

The chemical preparation of two folic acid derivatives, labelled with 125 I or 131 I, is described for use in radioimmunoassay of folic acid and its metabolites in biological fluids such as blood serum. Labelled compounds of the present invention more closely resemble folic acid in that they have glutamic acid in the terminal position. Examples of the use of these compounds in three different assays are given. (U.K.)

Radiolabeled derivatives of folic acid

International Nuclear Information System (INIS)

1980-01-01

Derivatives of folic acid are described, in which the α-carboxyl group is substituted with an amino compound having an aromatic or heterocyclic ring substituent which is capable of being radiolabelled. Particularly mentioned as a radiolabel is 125 I. (author)

Pd(II)-catalysed meta-C–H functionalizations of benzoic acid derivatives

Science.gov (United States)

Li, Shangda; Cai, Lei; Ji, Huafang; Yang, Long; Li, Gang

2016-01-01

Benzoic acids are highly important structural motifs in drug molecules and natural products. Selective C–H bond functionalization of benzoic acids will provide synthetically useful tools for step-economical organic synthesis. Although direct ortho-C–H functionalizations of benzoic acids or their derivatives have been intensely studied, the ability to activate meta-C–H bond of benzoic acids or their derivatives in a general manner via transition-metal catalysis has been largely unsuccessful. Although chelation-assisted meta-C–H functionalization of electron-rich arenes was reported, chelation-assisted meta-C–H activation of electron-poor arenes such as benzoic acid derivatives remains a formidable challenge. Herein, we report a general protocol for meta-C–H olefination of benzoic acid derivatives using a nitrile-based sulfonamide template. A broad range of benzoic acid derivatives are meta-selectively olefinated using molecular oxygen as the terminal oxidant. The meta-C–H acetoxylation, product of which is further transformed at the meta-position, is also reported. PMID:26813919

Hydrogen/deuterium exchange of cross-linkable alpha-amino acid derivatives in deuterated triflic acid

OpenAIRE

Wang, Lei; Murai, Yuta; Yoshida, Takuma; Okamoto, Masashi; Masuda, Katsuyoshi; Sakihama, Yasuko; Hashidoko, Yasuyuki; Hatanaka, Yasumaru; Hashimoto, Makoto

2014-01-01

In this paper we report here a hydrogen/deuterium exchange (H/D exchange) of cross-linkable alpha-amino acid derivatives with deuterated trifluoromethanesulfonic acid (TfOD). H/D exchange with TfOD was easily applied to o-catechol containing phenylalanine (DOPA) within an hour. A partial H/D exchange was observed for trifluoromethyldiazirinyl (TFMD) phenylalanine derivatives. N-Acetyl-protected natural aromatic alpha-amino acids (Tyr and Trp) were more effective in H/D exchange than unprotect...

Naturally Occurring Cinnamic Acid Sugar Ester Derivatives

Directory of Open Access Journals (Sweden)

Yuxin Tian

2016-10-01

Full Text Available Cinnamic acid sugar ester derivatives (CASEDs are a class of natural product with one or several phenylacrylic moieties linked with the non-anomeric carbon of a glycosyl skeleton part through ester bonds. Their notable anti-depressant and brains protective activities have made them a topic of great interest over the past several decades. In particular the compound 3′,6-disinapoylsucrose, the index component of Yuanzhi (a well-known Traditional Chinese Medicine or TCM, presents antidepressant effects at a molecular level, and has become a hotspot of research on new lead drug compounds. Several other similar cinnamic acid sugar ester derivatives are reported in traditional medicine as compounds to calm the nerves and display anti-depression and neuroprotective activity. Interestingly, more than one third of CASEDs are distributed in the family Polygalaceae. This overview discusses the isolation of cinnamic acid sugar ester derivatives from plants, together with a systematic discussion of their distribution, chemical structures and properties and pharmacological activities, with the hope of providing references for natural product researchers and draw attention to these interesting compounds.

Tritium derivatives of the glycyrrhetinic acid and procedure for its preparation

International Nuclear Information System (INIS)

Turner, J.C.

1977-01-01

The invention concerns tritium derivatives of glycyrrhetinic acid which is largely used to treat ulcers and inflammations, and it deals with a method for their production. The 3α- 3 H-glycyrrhetinic acid, 3 α- 3 H-carbene oxolone, Na-salt and basic Al salt of this carbene oxolone, as well as the acetyl derivates, piperazine amide derivatives and further derivatives of the glycyrrhetinic acid (e.g. cinnamyl ester) are claimed in nine examples. (HK) [de

Natural Cinnamic Acids, Synthetic Derivatives and Hybrids with Antimicrobial Activity

Directory of Open Access Journals (Sweden)

Juan David Guzman

2014-11-01

Full Text Available Antimicrobial natural preparations involving cinnamon, storax and propolis have been long used topically for treating infections. Cinnamic acids and related molecules are partly responsible for the therapeutic effects observed in these preparations. Most of the cinnamic acids, their esters, amides, aldehydes and alcohols, show significant growth inhibition against one or several bacterial and fungal species. Of particular interest is the potent antitubercular activity observed for some of these cinnamic derivatives, which may be amenable as future drugs for treating tuberculosis. This review intends to summarize the literature data on the antimicrobial activity of the natural cinnamic acids and related derivatives. In addition, selected hybrids between cinnamic acids and biologically active scaffolds with antimicrobial activity were also included. A comprehensive literature search was performed collating the minimum inhibitory concentration (MIC of each cinnamic acid or derivative against the reported microorganisms. The MIC data allows the relative comparison between series of molecules and the derivation of structure-activity relationships.

Glutamic acid and its derivatives: candidates for rational design of anticancer drugs.

Science.gov (United States)

Ali, Imran; Wani, Waseem A; Haque, Ashanul; Saleem, Kishwar

2013-05-01

Throughout the history of human civilizations, cancer has been a major health problem. Its treatment has been interesting but challenging to scientists. Glutamic acid and its derivative glutamine are known to play interesting roles in cancer genesis, hence, it was realized that structurally variant glutamic acid derivatives may be designed and developed and, might be having antagonistic effects on cancer. The present article describes the state-of-art of glutamic acid and its derivatives as anticancer agents. Attempts have been made to explore the effectivity of drug-delivery systems based on glutamic acid for the delivery of anticancer drugs. Moreover, efforts have also been made to discuss the mechanism of action of glutamic acid derivatives as anticancer agents, clinical applications of glutamic acid derivatives, as well as recent developments and future perspectives of glutamic acid drug development have also been discussed.

Structural Requirements of Alkylglyceryl-l-Ascorbic Acid Derivatives for Melanogenesis Inhibitory Activity.

Science.gov (United States)

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.

Docosahexaenoic Acid-Derived Fatty Acid Esters of Hydroxy Fatty Acids (FAHFAs) With Anti-inflammatory Properties.

Science.gov (United States)

Kuda, Ondrej; Brezinova, Marie; Rombaldova, Martina; Slavikova, Barbora; Posta, Martin; Beier, Petr; Janovska, Petra; Veleba, Jiri; Kopecky, Jan; Kudova, Eva; Pelikanova, Terezie; Kopecky, Jan

2016-09-01

White adipose tissue (WAT) is a complex organ with both metabolic and endocrine functions. Dysregulation of all of these functions of WAT, together with low-grade inflammation of the tissue in obese individuals, contributes to the development of insulin resistance and type 2 diabetes. n-3 polyunsaturated fatty acids (PUFAs) of marine origin play an important role in the resolution of inflammation and exert beneficial metabolic effects. Using experiments in mice and overweight/obese patients with type 2 diabetes, we elucidated the structures of novel members of fatty acid esters of hydroxy fatty acids-lipokines derived from docosahexaenoic acid (DHA) and linoleic acid, which were present in serum and WAT after n-3 PUFA supplementation. These compounds contained DHA esterified to 9- and 13-hydroxyoctadecadienoic acid (HLA) or 14-hydroxydocosahexaenoic acid (HDHA), termed 9-DHAHLA, 13-DHAHLA, and 14-DHAHDHA, and were synthesized by adipocytes at concentrations comparable to those of protectins and resolvins derived from DHA in WAT. 13-DHAHLA exerted anti-inflammatory and proresolving properties while reducing macrophage activation by lipopolysaccharides and enhancing the phagocytosis of zymosan particles. Our results document the existence of novel lipid mediators, which are involved in the beneficial anti-inflammatory effects attributed to n-3 PUFAs, in both mice and humans. © 2016 by the American Diabetes Association.

Synthesis and preliminary biological evaluations of (+)-isocampholenic acid-derived amides.

Science.gov (United States)

Grošelj, Uroš; Golobič, Amalija; Knez, Damijan; Hrast, Martina; Gobec, Stanislav; Ričko, Sebastijan; Svete, Jurij

2016-08-01

The synthesis of two novel (+)-isocampholenic acid-derived amines has been realized starting from commercially available (1S)-(+)-10-camphorsulfonic acid. The novel amines as well as (+)-isocampholenic acid have been used as building blocks in the construction of a library of amides using various aliphatic, aromatic, and amino acid-derived coupling partners using BPC and CDI as activating agents. Amide derivatives have been assayed against several enzymes that hold potential for the development of new drugs to battle bacterial infections and Alzheimer's disease. Compounds 20c and 20e showed promising selective sub-micromolar inhibition of human butyrylcholinesterase [Formula: see text] ([Formula: see text] values [Formula: see text] and [Formula: see text], respectively).

Caldensinic acid, a benzoic acid derivative and others compounds from Piper carniconnectivum

Energy Technology Data Exchange (ETDEWEB)

Alves, Harley da Silva; Souza, Maria de Fatima Vanderlei de; Chaves, Maria Celia de Oliveira, E-mail: cchaves@ltf.ufpb.b [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Lab. de Tecnologia Farmaceutica

2010-07-01

A benzoic acid derivative - caldensinic acid, E-phythyl hexadecanoate, {beta}-sitosterol and stigmasterol mixture and phaeophytin a were isolated from the aerial parts of Piper carniconnectivum. The structures of these compounds were established unambiguously by IR, MS, 1D and 2D NMR analysis. (author)

Amino acid derived 1,4-dialkyl substituted imidazolones

DEFF Research Database (Denmark)

Diness, Frederik; Meldal, Morten Peter

2010-01-01

A general method for synthesis of 1,4-substituted imidazolones from amino acids on solid support or in solution has been developed. Amino acid derived 3-Boc-(1,3)-oxazinane (Box) protected amino aldehyde building blocks were coupled through urea bonds to the amino terminal of dipeptides or amino...... acids. Upon acidic release, the aldehyde instantaneously formed the cyclic N-carbamyliminium ion, which rearranged to the corresponding imidazolone. Under strongly acidic conditions the imidazolones acted as nuclophiles in the Pictet-Spengler reaction....

Synthesis and stability of strongly acidic benzamide derivatives

DEFF Research Database (Denmark)

Diness, Frederik; Bjerrum, Niels J.; Begtrup, Mikael

2018-01-01

Reactivity studies of strong organic acids based on the replacement of one or both of the oxygens in benzoic acids with the trifluoromethanesulfonamide group are reported. Novel derivatives of these types of acids were synthesized in good yields. The generated N-triflylbenzamides were further...... functionalized through cross-coupling and nucleophilic aromatic substitution reactions. All compounds were stable in dilute aqueous solutions. Studies of stability under acidic and basic conditions are also reported....

2D-QSAR in hydroxamic acid derivatives as peptide deformylase inhibitors and antibacterial agents.

Science.gov (United States)

Gupta, Manish K; Mishra, Pradeep; Prathipati, Philip; Saxena, Anil K

2002-12-01

Peptide deformylase catalyzes the removal of N-formyl group from the N-formylmethionine of ribosome synthesized polypeptide in eubacteria. Quantitative structure-activity relationship (QSAR) studies have been carried out in a series of beta-sulfonyl and beta-sulfinyl hydroxamic acid derivatives for their PDF enzyme inhibitory and antibacterial activities against Escherichia coli DC2 and Moraxella catarrhalis RA21 which demonstrate that the PDF inhibitory activity in cell free and whole cell system increases with increase in molar refractivity and hydrophobicity. The comparison of the QSARs between the cell free and whole cell system indicate that the active binding sites in PDF isolated from E. coli and in M. catarrhalis RA21 are similar and the whole cell antibacterial activity is mainly due to the inhibition of PDF. Apart from this the QSARs on some matrixmetelloproteins (COL-1, COL-3, MAT and HME) and natural endopeptidase (NEP) indicate the possibilities of introducing selectivity in these hydroxamic acid derivatives for their PDF inhibitory activity.

Identification of marine-derived lipids in juvenile coho salmon and aquatic insects through fatty acid analysis

Science.gov (United States)

Heintz, Ron A.; Wipfli, Mark S.; Hudson, John P.

2010-01-01

The energetic benefits enjoyed by consumers in streams with salmon runs depend on how those benefits are accrued. Adult Pacific salmon Oncorhynchus spp. deliver significant amounts of nutrients (i.e., nitrogen and phosphorus) and carbon to streams when they spawn and die; these nutrient additions can have demonstrable effects on primary production in streams. Consumption of carcass tissues or eggs provides for direct energy subsidies to consumers and may have significant effects on their condition. In this study, comparisons of juvenile coho salmon O. kisutch and aquatic insects exposed to terrestrial and marine energy sources demonstrated that direct consumption of marine-derived lipids had a significant effect on the lipid reserves of consumers. Direct consumption of marine-derived tissues was verified through fatty acid analysis. Selected aquatic insects and juvenile coho salmon were reared for 6 weeks in experimental streams supplied with terrestrial or marine energy sources. Chironomid midges, nemourid stoneflies, and juvenile coho salmon exposed to the marine energy source altered their fatty acid compositions by incorporating the long-chain polyunsaturated fatty acids that are characteristic of marine fish. The fatty acid composition of baetid mayflies was unaffected. The direct movement of specific fatty markers indicated that direct consumption of marine-derived tissues led to increased energy reserves (triacylglycerols) in consumers. Similar results were obtained for juvenile coho salmon sampled from natural streams before and after the arrival of adult salmon runs. These data indicate that marine-derived lipids from anadromous fish runs are an important source of reserve lipids for consumers that overwinter in streams.

Synthesis and characterization of mixed ligand Cu(II) complexes of salicylic acid derivatives with 2-aminobenzotiyazol derivatives

OpenAIRE

İlkimen, Halil; Yenikaya, Cengiz

2018-01-01

In thisstudy, mixed ligand transitionmetal complexes of Cu(II)have been prepared between salicylic acid derivatives [salicylic acid (H2sal) or acetylsalicylic acid (Hasal)] and 2-aminobenzothiazole derivatives[2-aminobenzothiazole (abt) or 2-amino-6-chlorobenzothiazole (Clabt) or2-amino-6-methylbenzothiazole (Meabt)]. The structures of amorphous metalcomplexes have been proposed by evaluating the data obtained from elementalanalysis, ICP-OES, FT-IR, UV-Vis, thermal analysis, magnetic suscepti...

Acyl Meldrum's acid derivatives: application in organic synthesis

Science.gov (United States)

Janikowska, K.; Rachoń, J.; Makowiec, S.

2014-07-01

This review is focused on an important class of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleophiles. The possible mechanisms of these transformations are analyzed. The bibliography includes 134 references.

Complexing of vanadium(3) with chromotropic acid derivatives

International Nuclear Information System (INIS)

Babenko, N.L.; Busev, A.I.; Sukhorukova, N.V.; Frolova, O.S.

1976-01-01

A spectrophotometric study has been made of the complex formation of vanadium (3) with arsenazo(1), arsenazo(3) and some monosubstituted derivatives of chromotropic acid and sulphanylamides. In acid medium vanadium (3) reacts with each of these reagents to produce a 1:1 complex. Optimum conditions of the complex formation was found. The effect of H + on the complex formation of vanadium (3) with chromotropic acid derivatives was established. It was found by the graphical method that the formation of the complex is accompanied by the elimination of one proton. Patterns were found of the influence of the nature of substituents in the organic compound on the ionization constants of acid groups and stability of complexes. Molar extinction coefficients, equilibrium constants of the formation reactions and instability constants for the complexes were calculated. The structure of complexes was suggested. Similar behaviour of all the reagents was established in the complex formation with vanadium (3)

Study on reduction and back extraction of Pu(IV) by urea derivatives in nitric acid conditions

International Nuclear Information System (INIS)

Ye, G.A.; Xiao, S.T.; Yan, T.H.; Lin, R.S.; Zhu, Z.W.

2013-01-01

The reduction kinetics of Pu(IV) by hydroxyl-semicarbazide (HSC), hydroxyurea (HU) and di-hydroxyurea (DHU) in nitric acid solutions were investigated separately with adequate kinetic equations. In addition, counter-current cascade experiments were conducted for Pu split from U in nitric acid media using three kinds of reductant, respectively. The results show that urea derivatives as a kind of novel salt-free reductant can reduce Pu(IV) to Pu(III) rapidly in the nitric acid solutions. The stripping experimental results showed that Pu(IV) in the organic phase can be stripped rapidly to the aqueous phase by the urea derivatives, and the separation factors of plutonium /uranium can reach more than 10 4 . This indicates that urea derivatives is a kind of promising salt-free agent for uranium/plutonium separation. In addition, the complexing effect of HSC with Np(IV) was revealed, and Np(IV) can be back-extracted by HSC with a separation factor of about 20

Study on reduction and back extraction of Pu(IV) by urea derivatives in nitric acid conditions

Energy Technology Data Exchange (ETDEWEB)

Ye, G.A.; Xiao, S.T.; Yan, T.H.; Lin, R.S.; Zhu, Z.W. [China Institute of Atomic Energy, P.O.Box 275(26), Beijing 102413 (China)

2013-07-01

The reduction kinetics of Pu(IV) by hydroxyl-semicarbazide (HSC), hydroxyurea (HU) and di-hydroxyurea (DHU) in nitric acid solutions were investigated separately with adequate kinetic equations. In addition, counter-current cascade experiments were conducted for Pu split from U in nitric acid media using three kinds of reductant, respectively. The results show that urea derivatives as a kind of novel salt-free reductant can reduce Pu(IV) to Pu(III) rapidly in the nitric acid solutions. The stripping experimental results showed that Pu(IV) in the organic phase can be stripped rapidly to the aqueous phase by the urea derivatives, and the separation factors of plutonium /uranium can reach more than 10{sup 4}. This indicates that urea derivatives is a kind of promising salt-free agent for uranium/plutonium separation. In addition, the complexing effect of HSC with Np(IV) was revealed, and Np(IV) can be back-extracted by HSC with a separation factor of about 20.

Injectable hydrogels derived from phosphorylated alginic acid calcium complexes

Energy Technology Data Exchange (ETDEWEB)

Kim, Han-Sem; Song, Minsoo, E-mail: minsoosong00@gmail.com; Lee, Eun-Jung; Shin, Ueon Sang, E-mail: usshin12@dankook.ac.kr

2015-06-01

Phosphorylation of sodium alginate salt (NaAlg) was carried out using H{sub 3}PO{sub 4}/P{sub 2}O{sub 5}/Et{sub 3}PO{sub 4} followed by acid–base reaction with Ca(OAc){sub 2} to give phosphorylated alginic acid calcium complexes (CaPAlg), as a water dispersible alginic acid derivative. The modified alginate derivatives including phosphorylated alginic acid (PAlg) and CaPAlg were characterized by nuclear magnetic resonance spectroscopy for {sup 1}H, and {sup 31}P nuclei, high resolution inductively coupled plasma optical emission spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. CaPAlg hydrogels were prepared simply by mixing CaPAlg solution (2 w/v%) with NaAlg solution (2 w/v%) in various ratios (2:8, 4:6, 6:4, 8:2) of volume. No additional calcium salts such as CaSO{sub 4} or CaCl{sub 2} were added externally. The gelation was completed within about 3–40 min indicating a high potential of hydrogel delivery by injection in vivo. Their mechanical properties were tested to be ≤ 6.7 kPa for compressive strength at break and about 8.4 kPa/mm for elastic modulus. SEM analysis of the CaPAlg hydrogels showed highly porous morphology with interconnected pores of width in the range of 100–800 μm. Cell culture results showed that the injectable hydrogels exhibited comparable properties to the pure alginate hydrogel in terms of cytotoxicity and 3D encapsulation of cells for a short time period. The developed injectable hydrogels showed suitable physicochemical and mechanical properties for injection in vivo, and could therefore be beneficial for the field of soft tissue engineering. - Highlights: • Preparation of water-soluble alginic acid complexes with calcium phosphate • Self-assembly of the phosphorylated alginic acid calcium complexes with sodium alginate • Preparation of injectable hydrogels with diverse gelation times within about 3–40 min.

An Olfactory Indicator for Acid-Base Titrations.

Science.gov (United States)

Flair, Mark N.; Setzer, William N.

1990-01-01

The use of an olfactory acid-base indicator in titrations for visually impaired students is discussed. Potential olfactory indicators include eugenol, thymol, vanillin, and thiophenol. Titrations performed with each indicator with eugenol proved to be successful. (KR)

Production of Fatty Acid-Derived Valuable Chemicals in Synthetic Microbes

International Nuclear Information System (INIS)

Yu, Ai-Qun; Pratomo Juwono, Nina Kurniasih; Leong, Susanna Su Jan; Chang, Matthew Wook

2014-01-01

Fatty acid derivatives, such as hydroxy fatty acids, fatty alcohols, fatty acid methyl/ethyl esters, and fatty alka(e)nes, have a wide range of industrial applications including plastics, lubricants, and fuels. Currently, these chemicals are obtained mainly through chemical synthesis, which is complex and costly, and their availability from natural biological sources is extremely limited. Metabolic engineering of microorganisms has provided a platform for effective production of these valuable biochemicals. Notably, synthetic biology-based metabolic engineering strategies have been extensively applied to refactor microorganisms for improved biochemical production. Here, we reviewed: (i) the current status of metabolic engineering of microbes that produce fatty acid-derived valuable chemicals, and (ii) the recent progress of synthetic biology approaches that assist metabolic engineering, such as mRNA secondary structure engineering, sensor-regulator system, regulatable expression system, ultrasensitive input/output control system, and computer science-based design of complex gene circuits. Furthermore, key challenges and strategies were discussed. Finally, we concluded that synthetic biology provides useful metabolic engineering strategies for economically viable production of fatty acid-derived valuable chemicals in engineered microbes.

Production of Fatty Acid-Derived Valuable Chemicals in Synthetic Microbes

Energy Technology Data Exchange (ETDEWEB)

Yu, Ai-Qun; Pratomo Juwono, Nina Kurniasih [Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (Singapore); Synthetic Biology Research Program, National University of Singapore, Singapore (Singapore); Leong, Susanna Su Jan [Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (Singapore); Synthetic Biology Research Program, National University of Singapore, Singapore (Singapore); Singapore Institute of Technology, Singapore (Singapore); Chang, Matthew Wook, E-mail: bchcmw@nus.edu.sg [Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore (Singapore); Synthetic Biology Research Program, National University of Singapore, Singapore (Singapore)

2014-12-23

Fatty acid derivatives, such as hydroxy fatty acids, fatty alcohols, fatty acid methyl/ethyl esters, and fatty alka(e)nes, have a wide range of industrial applications including plastics, lubricants, and fuels. Currently, these chemicals are obtained mainly through chemical synthesis, which is complex and costly, and their availability from natural biological sources is extremely limited. Metabolic engineering of microorganisms has provided a platform for effective production of these valuable biochemicals. Notably, synthetic biology-based metabolic engineering strategies have been extensively applied to refactor microorganisms for improved biochemical production. Here, we reviewed: (i) the current status of metabolic engineering of microbes that produce fatty acid-derived valuable chemicals, and (ii) the recent progress of synthetic biology approaches that assist metabolic engineering, such as mRNA secondary structure engineering, sensor-regulator system, regulatable expression system, ultrasensitive input/output control system, and computer science-based design of complex gene circuits. Furthermore, key challenges and strategies were discussed. Finally, we concluded that synthetic biology provides useful metabolic engineering strategies for economically viable production of fatty acid-derived valuable chemicals in engineered microbes.

Selenium- or tellurium- containing bile acids and derivatives thereof

International Nuclear Information System (INIS)

Monks, R.; Riley, A.L.M.

1981-01-01

This invention relates to the preparation of selenium and tellurium derivatives, particularly γ-emitting radioactive derivatives of bile acids and bile salts. Such compounds are valuable in the examination of body function, especially small bowel function. (author)

A Tc-99m-labeled long chain fatty acid derivative for myocardial imaging.

Science.gov (United States)

Magata, Yasuhiro; Kawaguchi, Takayoshi; Ukon, Misa; Yamamura, Norio; Uehara, Tomoya; Ogawa, Kazuma; Arano, Yasushi; Temma, Takashi; Mukai, Takahiro; Tadamura, Eiji; Saji, Hideo

2004-01-01

C-11- and I-123-labeled long chain fatty acid derivatives have been reported as useful radiopharmaceuticals for the estimation of myocardial fatty acid metabolism. We have reported that Tc-99m-labeled N-[[[(2-mercaptoethyl)amino]carbonyl]methyl]-N-(2-mercaptoethyl)-6-aminohexanoic acid ([(99m)Tc]MAMA-HA), a medium chain fatty acid derivative, is metabolized by beta-oxidation in the liver and that the MAMA ligand is useful for attaching to the omega-position of fatty acid derivatives as a chelating group for Tc-99m. On the basis of these findings, we focused on developing a Tc-99m-labeled long chain fatty acid derivative that reflected fatty acid metabolism in the myocardium. In this study, we synthesized a dodecanoic acid derivative, MAMA-DA, and a hexadecanoic acid derivative, MAMA-HDA, and performed radiolabeling and biodistribution studies. [(99m)Tc]MAMA-DA and [(99m)Tc]MAMA-HDA were prepared using a ligand-exchange reaction. Biodistribution studies were carried out in normal mice and rats. Then, a high initial uptake of Tc-99m was observed, followed by a rapid clearance from the heart. The maximum heart/blood ratio was 3.6 at 2 min postinjection of [(99m)Tc]MAMA-HDA. These kinetics were similar to those with postinjection of p-[(125)I]iodophenylpentadecanoic acid. Metabolite analysis showed [(99m)Tc]MAMA-HDA was metabolized by beta-oxidation in the body. In conclusion, [(99m)Tc]MAMA-HDA is a promising compound as a long chain fatty acid analogue for estimating beta-oxidation of fatty acid in the heart.

Amino acid derivatives of 5-ASA as novel prodrugs for intestinal drug delivery.

Science.gov (United States)

Clerici, C; Gentili, G; Boschetti, E; Santucci, C; Aburbeh, A G; Natalini, B; Pellicciari, R; Morelli, A

1994-12-01

In an attempt to obtain site-specific delivery of 5-ASA in the intestinal tract, we have determined the extent of absorption and metabolism of a number of novel 5-ASA derivatives, namely, (N-L-glutamyl)-amino-2-salicylic acid (1), (N-L-aspartyl)-amino-2-salicylic-acid (2), 5-aminosalicyl-L-proline-L-leucine (3), and 5-(N-L-glutamyl)-aminosalicyl-L-proline-L-leucine (4), which are selectively cleaved by intestinal brush border aminopeptidase A and carboxypeptidases. These novel prodrugs, 5-ASA, and sulfasalazine were administered to adult Fisher rats (N = 30) and to animals that had undergone prior colostomy (N = 30). Urine and feces were collected at timed intervals for 48 hr and the metabolites, 5-ASA, and N-acetyl-5-ASA were measured by high-performance liquid chromatography. The absorption and metabolism of all compounds were essentially identical in colostomized and normal animals. 5-ASA exhibited a rapid proximal intestinal absorption as evidenced by the high cumulative urinary excretion (> 65%) and low fecal excretion. Sulfasalazine, as expected, exhibited a lower urinary recovery (metabolite. The novel glutamate and aspartate derivatives (1 and 2) behaved similarly to sulfasalazine, while administration of the proline-leucine derivative (3) resulted in urinary and fecal recovery values intermediate with respect to those observed with 5-ASA and sulfasalazine. 5-(N-L-Glutamyl)-aminosalicyl-L-proline-L-leucine yielded the highest fecal recovery of 5-ASA and its N-acetyl derivative, indicating a more efficient delivery to the distal bowel. Amino acid derivatives of 5-ASA appear to be potentially useful prodrugs for the site-specific delivery of 5-ASA to different regions of the intestinal tract.

Salicylic acid derivatives: synthesis, features and usage as therapeutic tools.

Science.gov (United States)

Ekinci, Deniz; Sentürk, Murat; Küfrevioğlu, Ömer İrfan

2011-12-01

In the field of medicinal chemistry, there is a growing interest in the use of small molecules. Although acetyl salicylic acid is well known for medical applications, little is known about other salicylic acid derivatives, and there is serious lack of data and information on the effects and biological evaluation that connect them. This review covers the synthesis and drug potencies of salicylic acid derivatives. After a brief overview of the information on salicylic acid and its features, a detailed review of salicylic acids as drugs and prodrugs, usage as cyclooxygenase inhibitors, properties in plants, synthesis and recent patents, is developed. Salicylic acid research is still an important area and innovations continue to arise, which offer hope for new therapeutics in related fields. It is anticipated that this review will guide the direction of long-term drug/nutraceutical safety trials and stimulate ideas for future research.

Factor Structure of Indices of the Second Derivative of the Finger Photoplethysmogram with Metabolic Components and Other Cardiovascular Risk Indicators

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Tomoyuki Kawada

2013-02-01

Full Text Available BackgroundThe second derivative of the finger photoplethysmogram (SDPTG is an indicator of arterial stiffness. The present study was conducted to clarify the factor structure of indices of the SDPTG in combination with components of the metabolic syndrome (MetS, to elucidate the significance of the SDPTG among various cardiovascular risk factors.MethodsThe SDPTG was determined in the second forefinger of the left hand in 1,055 male workers (mean age, 44.2±6.4 years. Among 4 waves of SDPTG components, the ratios of the height of the "a" wave to that of the "b" and "d" waves were expressed as b/a and d/a, and used as SDPTG indices for the analysis.ResultsPrincipal axis factoring analysis was conducted using age, SDPTG indices, components of MetS, and the serum levels of C-reactive protein (CRP and uric acid. Three factors were extracted, and the SDPTG indices were categorized in combination with age as the third factor. Metabolic components and the SDPTG indices were independently categorized. These three factors explained 44.4% of the total variation. Multiple logistic regression analysis revealed age, d/a, serum uric acid, serum CRP, and regular exercise as independent determinants of the risk of MetS. The odds ratios (95% confidence intervals were 1.08 (1.04 to 1.11, 0.10 (0.01 to 0.73, 1.24 (1.06 to 1.44, 3.59 (2.37 to 5.42, and 0.48 (0.28 to 0.82, respectively.ConclusionThe SDPTG indices were categorized in combination with age, and they differed in characteristics from components of MetS or inflammatory markers. In addition, this cross-sectional study also revealed decrease of the d/a as a risk factor for the development of MetS.

Metabolic Engineering of Yeast to Produce Fatty Acid-derived Biofuels: Bottlenecks and Solutions

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Jiayuan eSheng

2015-06-01

Full Text Available Fatty acid-derived biofuels can be a better solution than bioethanol to replace petroleum fuel, since they have similar energy content and combustion properties as current transportation fuels. The environmentally friendly microbial fermentation process has been used to synthesize advanced biofuels from renewable feedstock. Due to their robustness as well as the high tolerance to fermentation inhibitors and phage contamination, yeast strains such as Saccharomyces cerevisiae and Yarrowia lipolytica have attracted tremendous attention in recent studies regarding the production of fatty acid-derived biofuels, including fatty acids, fatty acid ethyl esters, fatty alcohols, and fatty alkanes. However, the native yeast strains cannot produce fatty acids and fatty acid-derived biofuels in large quantities. To this end, we have summarized recent publications in this review on metabolic engineering of yeast strains to improve the production of fatty acid-derived biofuels, identified the bottlenecks that limit the productivity of biofuels, and categorized the appropriate approaches to overcome these obstacles.

The remarkable stability of chimeric, sialic acid-derived alpha/delta-peptides in human blood plasma.

Science.gov (United States)

Saludes, Jonel P; Natarajan, Arutselvan; DeNardo, Sally J; Gervay-Hague, Jacquelyn

2010-05-01

Peptides are labile toward proteolytic enzymes, and structural modifications are often required to prolong their metabolic half-life and increase resistance. One modification is the incorporation of non-alpha-amino acids into the peptide to deter recognition by hydrolytic enzymes. We previously reported the synthesis of chimeric alpha/delta-peptides from glutamic acids (Glu) and the sialic acid derivative Neu2en. Conformational analyses revealed these constructs adopt secondary structures in water and may serve as conformational surrogates of polysialic acid. Polysialic acid is a tumor-associated polysaccharide and is correlated with cancer metastasis. Soluble polysialic acid is rapidly cleared from the blood limiting its potential for vaccine development. One motivation in developing structural surrogates of polysialic acid was to create constructs with increased bioavailability. Here, we report plasma stability profiles of Glu/Neu2en alpha/delta-peptides. DOTA was conjugated at the peptide N-termini by solid phase peptide synthesis, radiolabeled with (111)In, incubated in human blood plasma at 37 degrees C, and their degradation patterns monitored by cellulose acetate electrophoresis and radioactivity counting. Results indicate that these peptides exhibit a long half-life that is two- to three-orders of magnitude higher than natural alpha-peptides. These findings provide a viable platform for the synthesis of plasma stable, sialic acid-derived peptides that may find pharmaceutical application.

An Alternative to Synthetic Acid Base Indicator-Tagetes Erecta Linn

OpenAIRE

*A. Elumalai; M. C. Eswariah; M. K. Chinna; B. A. Kumar

2012-01-01

The present work highlights the use of the methanolic extract of the flowers of Tagetes erecta as an acid-base indicator in acid-base titrations. This natural indicator is easy to extract as well as easily available. Indicators used in titration show well marked changes of colour in certain intervals of pH. Most of these indicators are organic dyes and are of synthetic origin. Today synthetic indicators are the choice of acid-base titrations. But due to environmental pollution, availability a...

A Standard Structure for Bile Acids and Derivatives

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Francisco Meijide

2018-02-01

Full Text Available The crystal structures of two ester compounds (a monomer in its methyl ester form, with an amino isophthalic group, and a dimer in which the two steroid units are linked by a urea bridge recrystallized from ethyl acetate/methanol derived from cholic acid are described. Average bond lengths and bond angles from the crystal structures of 26 monomers and four dimers (some of them in several solvents of bile acids and esters (and derivatives are used for proposing a standard steroid nucleus. The hydrogen bond network and conformation of the lateral chain are also discussed. This standard structure was used to compare with the structures of both progesterone and cholesterol.

The substituent and solvent effects on the antioxidant activity of the ferulic acid derivations

International Nuclear Information System (INIS)

Najafi, M.; Bukhari, S.A.

2014-01-01

The antioxidant activity of ortho and meta substituted ferulic acid derivatives have been investigated in the gas phase and water. The reaction enthalpies of antioxidant activity of studied derivatives have been calculated and compared with corresponding values of ferulic acid. Results show that EWG substituents increase the BDE, IP, while EDG ones cause a rise in the PA. The ferulic acid derivatives with lowest BDE, IP and PA values were identified as the compounds with high antioxidant activity. Results show that the substituents at ortho position have high potential for synthesis of novel ferulic acid derivatives. Results show that ferulic acid derivatives can process their protective role via HAT and SPLET mechanism in gas phase and solvent, respectively. The calculated reaction enthalpies of the substituted ferulic acids have linear dependences with Hammett constants and EHOMO that can be utilized in the selection of suitable substituents for the synthesis of novel antioxidants based on ferulic acid. (author)

Isotope derivative assay of human serum bile acids

International Nuclear Information System (INIS)

Pageaux, J.F.; Duperray, B.; Dubois, M.; Pacheco, H.

1981-01-01

A new method for the selective determination of the main serum bile acids has been developed. Serum samples with added 14 C-labeled bile acid were submitted to deproteinization, alkaline hydrolysis, methylation, and were then chromatographed on alumina before acetylation with 2 microliters of [ 3 H]acetic anhydride. Excess reagent was eliminated by evaporation; elimination of residual tritiated contaminants and separation of the doubly labeled bile acid derivatives were obtained by thin-layer chromatography, column chromatography on Lipidex 5000, and crystallization. The sensitivity of the method is about 10 pmol of each bile acid. Analyses of seven sera with normal or elevated concentration of bile acids by the proposed method and gas-liquid chromatography showed a close correlation

Membrane extraction with thermodynamically unstable diphosphonic acid derivatives

Science.gov (United States)

Horwitz, E.P.; Gatrone, R.C.; Nash, K.L.

1997-10-14

Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described. 1 fig.

Acid-catalyzed rearrangements of flavans to novelbenzofuran derivatives

Science.gov (United States)

Richard W. Hemingway; Weiling Peng; Anthony H. Conner; Petrus J. Steynberg; Jan P. Steynberg

1998-01-01

The objective of this work was to define reactions that occur when proanthocyanidins and their derivatives are reacted in the presence of acid catalysts. Pure compounds (either as the free phenols, the methyl ether, or the methyl ether-acetate derivatives) were isolated by a variety of chromatographic methods. Proof of their structure was based mainly on 2D-NMR, as...

Radiosynthesis and in vitro evaluation of 99mTc(CO)3-labeled folic acid derivative

International Nuclear Information System (INIS)

Drishty Satpati; Archana Mukherjee; Meera Venkatesh; Sharmila Banerjee

2011-01-01

The over-expression of folate receptors in variety of neoplastic tissues makes radiolabeled folate conjugates potential agents for imaging and therapy of such cancers. With the aim of preparing an imaging agent for targeting folate receptors, folic acid has been conjugated with homocysteine for complexation with [ 99m Tc(CO) 3 (H 2 O) 3 ] + core. The radiolabeled complex of the homocysteine-folate could be obtained in >95% radiochemical yield as observed by HPLC. Stability of complex in saline was studied and challenge studies with histidine and cysteine revealed kinetic stability of the complex. Lipophilicity of the radiolabeled complex (log P) was found to be 0.45. In vitro uptake of 99m Tc(CO) 3 -labeled folic acid derivative was studied in KB cells and inhibition studies were carried out using 3 H-folic acid and cold homocysteine-folate conjugate. The in vitro studies indicated loss of binding affinity of the derivative towards folate receptors. (author)

Formation of taste-active amino acids, amino acid derivatives and peptides in food fermentations - A review.

Science.gov (United States)

Zhao, Cindy J; Schieber, Andreas; Gänzle, Michael G

2016-11-01

Fermented foods are valued for their rich and complex odour and taste. The metabolic activity of food-fermenting microorganisms determines food quality and generates odour and taste compounds. This communication reviews the formation of taste-active amino acids, amino acid derivatives and peptides in food fermentations. Pathways of the generation of taste compounds are presented for soy sauce, cheese, fermented meats, and bread. Proteolysis or autolysis during food fermentations generates taste-active amino acids and peptides; peptides derived from proteolysis particularly impart umami taste (e.g. α-glutamyl peptides) or bitter taste (e.g. hydrophobic peptides containing proline). Taste active peptide derivatives include pyroglutamyl peptides, γ-glutamyl peptides, and succinyl- or lactoyl amino acids. The influence of fermentation microbiota on proteolysis, and peptide hydrolysis, and the metabolism of glutamate and arginine is well understood, however, the understanding of microbial metabolic activities related to the formation of taste-active peptide derivatives is incomplete. Improved knowledge of the interactions between taste-active compounds will enable the development of novel fermentation strategies to develop tastier, less bitter, and low-salt food products, and may provide novel and "clean label" ingredients to improve the taste of other food products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Alkylation of Zwitterionic Thiooxalic Acid Derivatives

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Manfred Michalik

2001-05-01

Full Text Available The new S-alkyl thiooxal-1-hydrazono-2-amidrazonium halides 2-4 were synthesized by reaction of the corresponding zwitterionic thiooxalic acid derivatives 1 with alkyl halides in methanol. The structures of compounds 4b and 4d were proven by X-ray structural analysis. Both compounds form an interesting intermolecular network of hydrogen bonds in the solid state.

Synthesis and antimicrobial activities of new higher amino acid Schiff base derivatives of 6-aminopenicillanic acid and 7-aminocephalosporanic acid

Science.gov (United States)

Özdemir (nee Güngör), Özlem; Gürkan, Perihan; Özçelik, Berrin; Oyardı, Özlem

2016-02-01

Novel β-lactam derivatives (1c-3c) (1d-3d) were produced by using 6-aminopenicillanic acid (6-APA), 7-aminocephalosporanic acid (7-ACA) and the higher amino acid Schiff bases. The synthesized compounds were characterized by elemental analysis, IR, 1H/13C NMR and UV-vis spectra. Antibacterial activities of all the higher amino acid Schiff bases (1a-3a) (1b-3b) and β-lactam derivatives were screened against three gram negative bacteria (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Acinetobacter baumannii RSKK 02026), three gram positive bacteria (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 07005, Bacillus subtilis ATCC 6633) and their drug-resistant isolates by using broth microdilution method. Two fungi (Candida albicans and Candida krusei) were used for antifungal activity.

Bacterial metabolism of human polymorphonuclear leukocyte-derived arachidonic acid.

Science.gov (United States)

Sorrell, T C; Muller, M; Sztelma, K

1992-05-01

Evidence for transcellular bacterial metabolism of phagocyte-derived arachidonic acid was sought by exposing human blood polymorphonuclear leukocytes, prelabelled with [3H]arachidonic acid, to opsonized, stationary-phase Pseudomonas aeruginosa (bacteria-to-phagocyte ratio of 50:1) for 90 min at 37 degrees C. Control leukocytes were stimulated with the calcium ionophore A23187 (5 microM) for 5 min. Radiochromatograms of arachidonic acid metabolites, extracted from A23187-stimulated cultures and then separated by reverse-phase high-performance liquid chromatography, revealed leukotriene B4, its omega-oxidation products, and 5-hydroxy-eicosatetraenoic acid. In contrast, two major metabolite peaks, distinct from known polymorphonuclear leukocyte arachidonic acid products by high-performance liquid chromatography or by thin-layer chromatography, were identified in cultures of P. aeruginosa with [3H]arachidonic acid-labelled polymorphonuclear leukocytes. Respective chromatographic characteristics of these novel products were identical to those of two major metabolite peaks produced by incubation of stationary-phase P. aeruginosa with [3H]arachidonic acid. Production of the metabolites was dependent upon pseudomonal viability. UV spectral data were consistent with a conjugated diene structure. Metabolism of arachidonic acid by P. aeruginosa was not influenced by the presence of catalase, superoxide dismutase, nordihydroguaiaretic acid, ethanol, dimethyl sulfoxide, or ferrous ions but was inhibited by carbon monoxide, ketoconazole, and 1,2-epoxy-3,3,3-trichloropropane. Our data suggest that pseudomonal metabolism of polymorphonuclear leukocyte-derived arachidonic acid occurs during phagocytosis, probably by enzymatic epoxidation and hydroxylation via an oxygenase. By this means, potential proinflammatory effects of arachidonic acid or its metabolites may be modulated by P. aeruginosa at sites of infection in vivo.

Electrochemical and optical sugar sensors based on phenylboronic acid and its derivatives

Energy Technology Data Exchange (ETDEWEB)

Egawa, Yuya; Seki, Toshinobu [Faculty of Pharmaceutical Sciences, Josai University, Keyakidai, Sakado, Saitama 350-0295 (Japan); Takahashi, Shigehiro [Graduate School of Pharmaceutical Sciecnes, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578 (Japan); Anzai, Jun-ichi, E-mail: junanzai@mail.pharm.tohoku.ac.jp [Graduate School of Pharmaceutical Sciecnes, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578 (Japan)

2011-10-10

Recent progress in electrochemical and optical sugar sensors based on phenylboronic acid (PBA) and its derivatives as recognition components is reviewed. PBAs are known to bind diol compounds including sugars to form cyclic boronate esters that are negatively charged as a result of the addition of OH{sup -} ions from solution. Based on the formation of PBA charged species, sugars and their derivatives can be detected by means of electrochemical and optical techniques. For the development of PBA-based electrochemical sensing systems or sensors, PBA is modified with a redox-active marker, because PBA itself is electrochemically inactive, and ferrocene derivatives are often employed for this purpose. Ferrocene-modified PBAs have been used as redox-active additives in solution for the electrochemical detection of sugars and derivatives. PBA-modified electrodes have also been constructed as reagentless electrochemical sensors, where PBAs are immobilized on the surface of metal and carbon electrodes through mainly two routes: as a self-assembled monolayer film and as a polymer thin film. PBA-modified electrodes can be successfully used to detect sugars and derivatives through potentiometric and voltammetric responses. In addition, PBA-modified electrodes can be used for the immobilization of glycoenzymes on an electrode surface by the formation of boronate esters with carbohydrate chains in the glycoenzymes, thus resulting in enzyme biosensors. For the development of PBA-based optical sensors, a variety of chromophores and fluorophores have been coupled with PBA. Azobenzene dyes have been most frequently used for the preparation of colorimetric sugar sensors, in which the absorption wavelength and intensity of the dye are dependent on the type and concentration of added sugars. The sensitivity of the sensors is significantly improved based on multi-component systems in which alizalin red S, pyrocatechol violet, starch-iodine complex, and cyclodextrin are employed as

Electrochemical and optical sugar sensors based on phenylboronic acid and its derivatives

International Nuclear Information System (INIS)

Egawa, Yuya; Seki, Toshinobu; Takahashi, Shigehiro; Anzai, Jun-ichi

2011-01-01

Recent progress in electrochemical and optical sugar sensors based on phenylboronic acid (PBA) and its derivatives as recognition components is reviewed. PBAs are known to bind diol compounds including sugars to form cyclic boronate esters that are negatively charged as a result of the addition of OH - ions from solution. Based on the formation of PBA charged species, sugars and their derivatives can be detected by means of electrochemical and optical techniques. For the development of PBA-based electrochemical sensing systems or sensors, PBA is modified with a redox-active marker, because PBA itself is electrochemically inactive, and ferrocene derivatives are often employed for this purpose. Ferrocene-modified PBAs have been used as redox-active additives in solution for the electrochemical detection of sugars and derivatives. PBA-modified electrodes have also been constructed as reagentless electrochemical sensors, where PBAs are immobilized on the surface of metal and carbon electrodes through mainly two routes: as a self-assembled monolayer film and as a polymer thin film. PBA-modified electrodes can be successfully used to detect sugars and derivatives through potentiometric and voltammetric responses. In addition, PBA-modified electrodes can be used for the immobilization of glycoenzymes on an electrode surface by the formation of boronate esters with carbohydrate chains in the glycoenzymes, thus resulting in enzyme biosensors. For the development of PBA-based optical sensors, a variety of chromophores and fluorophores have been coupled with PBA. Azobenzene dyes have been most frequently used for the preparation of colorimetric sugar sensors, in which the absorption wavelength and intensity of the dye are dependent on the type and concentration of added sugars. The sensitivity of the sensors is significantly improved based on multi-component systems in which alizalin red S, pyrocatechol violet, starch-iodine complex, and cyclodextrin are employed as

Extracting metal ions with diphosphonic acid, or derivative thereof

Science.gov (United States)

Horwitz, Earl P.; Gatrone, Ralph C.; Nash, Kenneth L.

1994-01-01

Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulphur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described.

Therapeutic Applicability of Anti-Inflammatory and Proresolving Polyunsaturated Fatty Acid-Derived Lipid Mediators

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Gerard L. Bannenberg

2010-01-01

Full Text Available The enzymatic oxygenation of polyunsaturated fatty acids by lipoxygenases and cyclo-oxygenases is a resourceful mode of formation of specific autacoids that regulate the extent and pace of the inflammatory response. Arachidonate-derived eicosanoids, such as lipoxin A4, prostaglandin (PGD2, PGF2α, PGE2, and PGD2-derived cyclopentenones exert specific roles in counter-regulating inflammation and turning on resolution. Recently recognized classes of autacoids derived from long-chain ω-3 polyunsaturated fatty acids, the E- and D-series resolvins, protectin D1, and maresin 1, act as specialized mediators to dampen inflammation actively, afford tissue protection, stimulate host defense, and activate resolution. It is held that counter-regulatory lipid mediators and the specific molecular pathways activated by such endogenous agonists may be suitable for pharmacological use in the treatment of inflammatory disease. The anti-inflammatory drug aspirin is a striking example of a drug that is able to act in such a manner, namely through triggering the formation of 15-epi-lipoxin A4 and aspirin-triggered resolvins. Different aspects of the therapeutic applicability of lipid mediators have been addressed here, and indicate that the development of innovative pharmacotherapy based on anti-inflammatory and proresolution lipid mediators presents novel prospects for the treatment of inflammatory disease.

Photooxidative cleavage of 4(1H)-quinolinones to 2-acylaminobenzoic acids and derivatives

Energy Technology Data Exchange (ETDEWEB)

Staskun, B. (University of the Witwatersrand, Johannesburg (South Africa). Dept. of Chemistry); Foote, C.S. (California Univ., Los Angeles (USA). Dept. of Chemistry)

1984-12-01

4(1H)-Quinolinones undergo oxidative cleavage to afford the corresponding 2-acylaminobenzoic acids when subjected to dye-sensitized photooxygenation in methanol-aqueous sodium hydroxide solution. The derived 2-aminobenzoic acid was the predominant product in certain instances. The reaction, with singlet oxygen suggested as the active species, provides an alternative methodology for access to nuclear- substituted anthranilic acids and derivatives.

Synthesis and Application of Phenyl Nitrone Derivatives as Acidic and Microbial Corrosion Inhibitors

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Shijun Chen

2015-01-01

Full Text Available Nitrone has drawn great attention due to its wide applications as a 1,3-dipole in heterocyclic compounds synthesis and the bioactivities. With the special structure, nitrone can also be used as ligand in inorganic chemistry. Based on the current research, the nitrones are anticipated to be effective inhibitors against acidic and microbial corrosion. The aim of this work is to investigate the inhibitory action of nitrones. In this work, a series of phenyl nitrone derivatives (PN was synthesized and used as acidic and microbial corrosion inhibitors. The results indicate that several compounds show moderate to high inhibition efficiency (IE in 3% HCl. Accompanied with HMTA or BOZ, the IEs greatly increase, and the highest efficiency of 98.5% was obtained by using PN4 + BOZ. Investigation of the antibacterial activity against oilfield microorganism shows that the nitrone derivatives can inhibit SRB, IB, and TGB with moderate to high efficiency under 1,000 mg/L, which makes them potential to be used as bifunctional oilfield chemicals.

Extracting metal ions with diphosphonic acid, or derivative thereof

Science.gov (United States)

Horwitz, E.P.; Gatrone, R.C.; Nash, K.L.

1994-07-26

Thermodynamically-unstable complexing agents which are diphosphonic acids and diphosphonic acid derivatives (or sulfur containing analogs), like carboxyhydroxymethanediphosphonic acid and vinylidene-1,1-diphosphonic acid, are capable of complexing with metal ions, and especially metal ions in the II, III, IV, V and VI oxidation states, to form stable, water-soluble metal ion complexes in moderately alkaline to highly-acidic media. However, the complexing agents can be decomposed, under mild conditions, into non-organic compounds which, for many purposes are environmentally-nondamaging compounds thereby degrading the complex and releasing the metal ion for disposal or recovery. Uses for such complexing agents as well as methods for their manufacture are also described. 1 fig.

Recent developments in altering the fatty acid composition of ruminant-derived foods.

Science.gov (United States)

Shingfield, K J; Bonnet, M; Scollan, N D

2013-03-01

There is increasing evidence to indicate that nutrition is an important factor involved in the onset and development of several chronic human diseases including cancer, cardiovascular disease (CVD), type II diabetes and obesity. Clinical studies implicate excessive consumption of medium-chain saturated fatty acids (SFA) and trans-fatty acids (TFA) as risk factors for CVD, and in the aetiology of other chronic conditions. Ruminant-derived foods are significant sources of medium-chain SFA and TFA in the human diet, but also provide high-quality protein, essential micronutrients and several bioactive lipids. Altering the fatty acid composition of ruminant-derived foods offers the opportunity to align the consumption of fatty acids in human populations with public health policies without the need for substantial changes in eating habits. Replacing conserved forages with fresh grass or dietary plant oil and oilseed supplements can be used to lower medium-chain and total SFA content and increase cis-9 18:1, total conjugated linoleic acid (CLA), n-3 and n-6 polyunsaturated fatty acids (PUFA) to a variable extent in ruminant milk. However, inclusion of fish oil or marine algae in the ruminant diet results in marginal enrichment of 20- or 22-carbon PUFA in milk. Studies in growing ruminants have confirmed that the same nutritional strategies improve the balance of n-6/n-3 PUFA, and increase CLA and long-chain n-3 PUFA in ruminant meat, but the potential to lower medium-chain and total SFA is limited. Attempts to alter meat and milk fatty acid composition through changes in the diet fed to ruminants are often accompanied by several-fold increases in TFA concentrations. In extreme cases, the distribution of trans 18:1 and 18:2 isomers in ruminant foods may resemble that of partially hydrogenated plant oils. Changes in milk fat or muscle lipid composition in response to diet are now known to be accompanied by tissue-specific alterations in the expression of one or more

Hypolipidaemic and antiplatelet activity of phenoxyacetic acid derivatives related to alpha-asarone.

Science.gov (United States)

Pérez-Pastén, Ricardo; García, Rosa Virginia; Garduño, Leticia; Reyes, Elba; Labarrios, Fernando; Tamariz, Joaquín; Chamorro, Germán

2006-10-01

The phenoxyacetic acid derivatives 1-6 [2-methoxy-4-(2-propenyl)phenoxyacetic acid (1); 2-methoxy-5-nitro-4-(2-propenyl)phenoxyacetic acid (2); methyl 2-methoxy-4-(2-propenyl)phenoxyacetate (3); ethyl 2-methoxy-4-(2-propenyl)phenoxyacetate (4); methyl 2-methoxy-5-nitro-4-(2-propenyl)phenoxyacetate (5); ethyl 2-methoxy-5-nitro-4-(2-propenyl)phenoxyacetate (6)] related to alpha-asarone have been reported previously as hypolipidaemic agents in diet-induced hyperlipidaemic mice. We have aimed to expand the pharmacological profile of these derivatives by investigating their hypolipidaemic activity in rats and mice under different experimental conditions. The antiplatelet activity was tested also in-vitro from blood derived from consenting healthy volunteers. In normolipidaemic rats, compounds 2, 3 and 5 at oral doses of 40 and 80 mg kg(-1) significantly decreased total cholesterol and LDL-cholesterol levels. Moreover, analogues 3 and 5 administered to hypercholesterolaemic rats at the same doses for seven days also produced a reduction in the content of these same lipoproteins. In neither case were the high-density lipoprotein cholesterol and triglyceride concentrations affected. However, practically all tested compounds were found to be hypocholesterolaemic agents, and were shown to effectively lower low-density lipoprotein cholesterol and triglyceride levels in Triton-induced hyperlipidaemic mice at oral doses of 50 and 100 mg kg(-1). In all tests, all animals appeared to be healthy throughout the experimental period in their therapeutic ranges. Triton-induced hypercholesterolaemic mice appeared to be a desirable model for this class of hypolipidaemic drugs. On the other hand, compounds 1, 2, 4 and 5 significantly inhibited ADP-induced aggregation in-vitro. These findings indicated that all of these compounds appeared to be promising for the treatment of human hyperlipidaemia and thrombotic diseases.

Acyl Meldrum's acid derivatives: application in organic synthesis

International Nuclear Information System (INIS)

Janikowska, K; Rachoń, J; Makowiec, S

2014-01-01

This review is focused on an important class of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleophiles. The possible mechanisms of these transformations are analyzed. The bibliography includes 134 references

Plant amino acid-derived vitamins: biosynthesis and function.

Science.gov (United States)

Miret, Javier A; Munné-Bosch, Sergi

2014-04-01

Vitamins are essential organic compounds for humans, having lost the ability to de novo synthesize them. Hence, they represent dietary requirements, which are covered by plants as the main dietary source of most vitamins (through food or livestock's feed). Most vitamins synthesized by plants present amino acids as precursors (B1, B2, B3, B5, B7, B9 and E) and are therefore linked to plant nitrogen metabolism. Amino acids play different roles in their biosynthesis and metabolism, either incorporated into the backbone of the vitamin or as amino, sulfur or one-carbon group donors. There is a high natural variation in vitamin contents in crops and its exploitation through breeding, metabolic engineering and agronomic practices can enhance their nutritional quality. While the underlying biochemical roles of vitamins as cosubstrates or cofactors are usually common for most eukaryotes, the impact of vitamins B and E in metabolism and physiology can be quite different on plants and animals. Here, we first aim at giving an overview of the biosynthesis of amino acid-derived vitamins in plants, with a particular focus on how this knowledge can be exploited to increase vitamin contents in crops. Second, we will focus on the functions of these vitamins in both plants and animals (and humans in particular), to unravel common and specific roles for vitamins in evolutionary distant organisms, in which these amino acid-derived vitamins play, however, an essential role.

Microwave-induced facile synthesis of water-soluble fluorogenic alginic acid derivatives.

Science.gov (United States)

Chhatbar, Mahesh U; Meena, Ramavatar; Prasad, Kamalesh; Chejara, Dharmesh R; Siddhanta, A K

2011-04-01

A facile microwave-induced method was developed for synthesizing water-soluble fluorescent derivatives of alginic acid (ALG) with four different diamines, hydrazine (HY), ethylenediamine (EDA), 1,6-hexanediamine (HDA), and 1,4-cyclohexanediamine (CHDA), followed by a cross-linking reaction with a natural cross linker genipin. The ethylenediamine derivative of alginic acid (ALG-EDA) exhibited good fluorescent activity, which upon cross linking was enhanced threefold. The other amide derivatives, for example, ALG-HY, ALG-HDA, and ALG-CHDA, were not fluorescent, but their respective crosslinked products exhibited excellent fluorescent activity. The fluorescence intensity had an inverse correlation with the number of carbon atoms present in the amine, which in turn was a function of degree of substitution (DS). These fluorescent polysaccharide derivatives are of potential utility in the domain of sensor applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

Copper(I) mediated cross-coupling of amino acid derived organozinc reagents with acid chlorides

DEFF Research Database (Denmark)

Hjelmgaard, Thomas; Tanner, David Ackland

2006-01-01

This paper describes the development of a straightforward experimental protocol for copper-mediated cross-coupling of amino acid derived beta-amido-alkylzinc iodides 1 and 3 with a range of acid chlorides. The present method uses CuCN center dot 2LiCl as the copper source and for organozinc reagent...... 1 the methodology appears to be limited to reaction with more stable acid chlorides, providing the desired products in moderate yields. When applied to organozinc reagent 3, however, the protocol is more general and provides the products in good yields in all but one of the cases tested....

Benzoic acid derivatives: Evaluation of thermochemical properties with complementary experimental and computational methods

International Nuclear Information System (INIS)

Verevkin, Sergey P.; Zaitsau, Dzmitry H.; Emeĺyanenko, Vladimir N.; Stepurko, Elena N.; Zherikova, Kseniya V.

2015-01-01

Highlights: • Vapor pressures of benzoic acid derivatives were measured. • Sublimation enthalpies were derived and compared with the literature. • Thermochemical data tested for consistency using additivity rules and computations. • Contradiction between available enthalpies of sublimation was resolved. • Pairwise interactions of substituents on the benzene ring were derived. - Abstract: Molar sublimation enthalpies of the methyl- and methoxybenzoic acids were derived from the transpiration method, static method, and TGA. Thermochemical data available in the literature were collected, evaluated, and combined with own experimental results. This collection together with the new experimental results reported here has helped to resolve contradictions in the available enthalpy data and to recommend sets of sublimation and formation enthalpies for the benzoic acid derivatives. Gas-phase enthalpies of formation calculated with the G4 quantum-chemical method were in agreement with the experiment. Pairwise interactions of the methyl, methoxy, and carboxyl substituents on the benzene ring were derived and used for the development of simple group-additivity procedures for estimation of the vaporization enthalpies, gas-phase, and liquid-phase enthalpies of formation of substituted benzenes.

Benzoic acid derivatives: Evaluation of thermochemical properties with complementary experimental and computational methods

Energy Technology Data Exchange (ETDEWEB)

Verevkin, Sergey P., E-mail: sergey.verevkin@uni-rostock.de [Department of Physical Chemistry and Department “Science and Technology of Life, Light and Matter”, University of Rostock, D-18059 Rostock (Germany); Department of Physical Chemistry, Kazan Federal University, 420008 Kazan (Russian Federation); Zaitsau, Dzmitry H. [Department of Physical Chemistry, Kazan Federal University, 420008 Kazan (Russian Federation); Emeĺyanenko, Vladimir N. [Department of Physical Chemistry and Department “Science and Technology of Life, Light and Matter”, University of Rostock, D-18059 Rostock (Germany); Stepurko, Elena N. [Chemistry Faculty and Research Institute for Physical Chemical Problems, Belarusian State University, 220030 Minsk (Belarus); Zherikova, Kseniya V. [Nikolaev Institute of Inorganic Chemistry of Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk (Russian Federation)

2015-12-20

Highlights: • Vapor pressures of benzoic acid derivatives were measured. • Sublimation enthalpies were derived and compared with the literature. • Thermochemical data tested for consistency using additivity rules and computations. • Contradiction between available enthalpies of sublimation was resolved. • Pairwise interactions of substituents on the benzene ring were derived. - Abstract: Molar sublimation enthalpies of the methyl- and methoxybenzoic acids were derived from the transpiration method, static method, and TGA. Thermochemical data available in the literature were collected, evaluated, and combined with own experimental results. This collection together with the new experimental results reported here has helped to resolve contradictions in the available enthalpy data and to recommend sets of sublimation and formation enthalpies for the benzoic acid derivatives. Gas-phase enthalpies of formation calculated with the G4 quantum-chemical method were in agreement with the experiment. Pairwise interactions of the methyl, methoxy, and carboxyl substituents on the benzene ring were derived and used for the development of simple group-additivity procedures for estimation of the vaporization enthalpies, gas-phase, and liquid-phase enthalpies of formation of substituted benzenes.

Mass spectrometric studies of stable isotope-labelled carboxylic acid derivatives

International Nuclear Information System (INIS)

Andersson, B.Aa.; Dinger, F.; Dinh-Nguyen, N.

1975-01-01

Low resolution mass spectra of deuterium and carbon-13 labelled fatty acid pyrrolidides are discussed. The simple fragmentation pattern of pyrrolidides makes them superior to other derivatives, regarding location of isotopes. Deuteriation of ethylenic fatty acid pyrrolidides therefore seems to be an improved method to locate carbon-carbon double bonds by mass spectrometry. (author)

Utilization of acidic α-amino acids as acyl donors: an effective stereo-controllable synthesis of aryl-keto α-amino acids and their derivatives.

Science.gov (United States)

Wang, Lei; Murai, Yuta; Yoshida, Takuma; Okamoto, Masashi; Tachrim, Zetryana Puteri; Hashidoko, Yasuyuki; Hashimoto, Makoto

2014-05-16

Aryl-keto-containing α-amino acids are of great importance in organic chemistry and biochemistry. They are valuable intermediates for the construction of hydroxyl α-amino acids, nonproteinogenic α-amino acids, as well as other biofunctional components. Friedel-Crafts acylation is an effective method to prepare aryl-keto derivatives. In this review, we summarize the preparation of aryl-keto containing α-amino acids by Friedel-Crafts acylation using acidic α-amino acids as acyl-donors and Lewis acids or Brönsted acids as catalysts.

Study of antileishmanial activity of 2-aminobenzoyl amino acid hydrazides and their quinazoline derivatives.

Science.gov (United States)

Khattab, Sherine Nabil; Haiba, Nesreen Saied; Asal, Ahmed Mosaad; Bekhit, Adnan A; Guemei, Aida A; Amer, Adel; El-Faham, Ayman

2017-02-15

A new small library of 2-aminobenzoyl amino acid hydrazide derivatives and quinazolinones derivatives was synthesized and fully characterized by IR, NMR, and elemental analysis. The activity of the prepared compounds on the growth of Leishmania aethiopica promastigotes was evaluated. 2-Benzoyl amino acid hydrazide showed higher inhibitory effect than the quinazoline counterpart. The in vitro antipromastigote activity demonstrated that compounds 2a, 2b, 2f and 4a had IC 50 better than standard drug miltefosine and comparable activity to amphotericin B deoxycholate, which indicates their high antileishmanial activity against Leishmania. aethiopica. Among the prepared compounds; 2-amino-N-(6-hydrazinyl-6-oxohexyl)benzamide 2f (IC 50 =0.051μM) has the best activity, 154 folds more active than reference standard drug miltefosine (IC 50 =7.832μM), and half fold the activity of amphotericin B (IC 50 =0.035μM). In addition, this compound was safe and well tolerated by experimental animals orally up to 250mg/kg and parenterally up to 100mg/kg. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthesis and antimycobacterial activity of isoniazid derivatives from renewable fatty acids.

Science.gov (United States)

Rodrigues, Marieli O; Cantos, Jéssica B; D'Oca, Caroline R Montes; Soares, Karina L; Coelho, Tatiane S; Piovesan, Luciana A; Russowsky, Dennis; da Silva, Pedro A; D'Oca, Marcelo G Montes

2013-11-15

This work describes the synthesis of a series of fatty acid hydrazide derivatives of isoniazid (INH). The compounds were tested against Mycobacterium tuberculosis H37Rv (ATCC 27294) as well as INH-resistant (ATCC 35822 and 1896 HF) and rifampicin-resistant (ATCC 35338) M. tuberculosis strains. The fatty acid derivatives of INH showed high antimycobacterial potency against the studied strains, which is desirable for a pharmaceutical compound, suggesting that the increased lipophilicity of isoniazid plays an important role in its antimycobacterial activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Computational study of molecular electrostatic potential, docking and dynamics simulations of gallic acid derivatives as ABL inhibitors.

Science.gov (United States)

Raghi, K R; Sherin, D R; Saumya, M J; Arun, P S; Sobha, V N; Manojkumar, T K

2018-04-05

Chronic myeloid leukemia (CML), a hematological malignancy arises due to the spontaneous fusion of the BCR and ABL gene, resulting in a constitutively active tyrosine kinase (BCR-ABL). Pharmacological activity of Gallic acid and 1,3,4-Oxadiazole as potential inhibitors of ABL kinase has already been reported. Objective of this study is to evaluate the ABL kinase inhibitory activity of derivatives of Gallic acid fused with 1,3,4-Oxadiazole moieties. Attempts have been made to identify the key structural features responsible for drug likeness of the Gallic acid and the 1,3,4-Oxadiazole ring using molecular electrostatic potential maps (MESP). To investigate the inhibitory activity of Gallic acid derivatives towards the ABL receptor, we have applied molecular docking and molecular dynamics (MD) simulation approaches. A comparative study was performed using Bosutinib as the standard which is an approved CML drug acting on the same receptor. Furthermore, the novel compounds designed and reported here in were evaluated for ADME properties and the results indicate that they show acceptable pharmacokinetic properties. Accordingly these compounds are predicted to be drug like with low toxicity potential. Copyright © 2018 Elsevier Ltd. All rights reserved.

Novel Eicosapentaenoic Acid-derived F3-isoprostanes as Biomarkers of Lipid Peroxidation*

Science.gov (United States)

Song, Wen-Liang; Paschos, Georgios; Fries, Susanne; Reilly, Muredach P.; Yu, Ying; Rokach, Joshua; Chang, Chih-Tsung; Patel, Pranav; Lawson, John A.; FitzGerald, Garret A.

2009-01-01

Isoprostanes (iPs) are prostaglandin (PG) isomers generated by free radical-catalyzed peroxidation of polyunsaturated fatty acids (PUFAs). Urinary F2-iPs, PGF2α isomers derived from arachidonic acid (AA) are used as indices of lipid peroxidation in vivo. We now report the characterization of two major F3-iPs, 5-epi-8,12-iso-iPF3α-VI and 8,12-iso-iPF3α-VI, derived from the ω-3 fatty acid, eicosapentaenoic acid (EPA). Although the potential therapeutic benefits of EPA receive much attention, a shift toward a diet rich in ω-3 PUFAs may also predispose to enhanced lipid peroxidation. Urinary 5-epi-8,12-iso-iPF3α-VI and 8,12-iso-iPF3α-VI are highly correlated and unaltered by cyclooxygenase inhibition in humans. Fish oil dose-dependently elevates urinary F3-iPs in mice and a shift in dietary ω-3/ω-6 PUFAs is reflected by an increasing slope [m] of the line relating urinary 8, 12-iso-iPF3α-VI and 8,12-iso-iPF2α-VI. Administration of bacterial lipopolysaccharide evokes a reversible increase in both urinary 8,12-iso-iPF3α-VI and 8,12-iso-iPF2α-VI in humans on an ad lib diet. However, while excretion of the iPs is highly correlated (R2 median = 0.8), [m] varies by an order of magnitude, reflecting marked inter-individual variability in the relative peroxidation of ω-3 versus ω-6 substrates. Clustered analysis of F2- and F3-iPs refines assessment of the oxidant stress response to an inflammatory stimulus in vivo by integrating variability in dietary intake of ω-3/ω-6 PUFAs. PMID:19520854

Hippeastrum hybridum anthocyanins as indicators of endpoint in acid

African Journals Online (AJOL)

Anthocyanins from Hippeastrum hybridum (Amaryllis) were investigated as indicators of endpoint in acid- base titrations. Extraction of the anthocyanins was done using distilled water, methanol and methanol containing 0.5% acetic acid. The extracts were used in determination of endpoint in titrations between strong.

A new coruleoellagic acid derivative from stems of Rhodamnia dumetorum.

Science.gov (United States)

Lakornwong, Waranya; Kanokmedhakul, Kwanjai; Kanokmedhakul, Somdej

2018-07-01

A new coruleoellagic acid derivative, 3,3',4,4',5'-pentamethylcoruleoellagic acid (1) together with nine known compounds, hexamethylcoruleoellagic acid (2), 3,4,3'-tri-O-methylellagic acid (3), heptaphylline (4), 7-methoxymukonal (5), dentatin (6), sinapaldehyde (7), gallic acid (8), 2,6-dimethoxy-4H-pyran-4-one (9) and β-sitosterol (10) were isolated from the stems of Rhodamnia dumetorum. Their structures were identified by physical and spectroscopic data (IR, 1D and 2D NMR, and MS). Compounds 1, 2 and 7-10 were tested for antibacterial activity against six pathogenic bacterial strains (Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica serovar Typhimurium, Staphylococcus aureus, and Methicillin resistant S. aureus (MRSA)).

Somite-Derived Retinoic Acid Regulates Zebrafish Hematopoietic Stem Cell Formation.

Directory of Open Access Journals (Sweden)

Laura M Pillay

Full Text Available Hematopoietic stem cells (HSCs are multipotent progenitors that generate all vertebrate adult blood lineages. Recent analyses have highlighted the importance of somite-derived signaling factors in regulating HSC specification and emergence from dorsal aorta hemogenic endothelium. However, these factors remain largely uncharacterized. We provide evidence that the vitamin A derivative retinoic acid (RA functions as an essential regulator of zebrafish HSC formation. Temporal analyses indicate that RA is required for HSC gene expression prior to dorsal aorta formation, at a time when the predominant RA synthesis enzyme, aldh1a2, is strongly expressed within the paraxial mesoderm and somites. Previous research implicated the Cxcl12 chemokine and Notch signaling pathways in HSC formation. Consequently, to understand how RA regulates HSC gene expression, we surveyed the expression of components of these pathways in RA-depleted zebrafish embryos. During somitogenesis, RA-depleted embryos exhibit altered expression of jam1a and jam2a, which potentiate Notch signaling within nascent endothelial cells. RA-depleted embryos also exhibit a severe reduction in the expression of cxcr4a, the predominant Cxcl12b receptor. Furthermore, pharmacological inhibitors of RA synthesis and Cxcr4 signaling act in concert to reduce HSC formation. Our analyses demonstrate that somite-derived RA functions to regulate components of the Notch and Cxcl12 chemokine signaling pathways during HSC formation.

Spectrophotometric study into complexing of vanadium(3) with salicylic acid derivatives

Energy Technology Data Exchange (ETDEWEB)

Dolgorev, A V; Serikov, Yu A; Zolotavin, V L

1977-03-01

Complexing of vanadium (3) with 5 amino-salicylic acid and amide of salicylhydroxamic acid has been studied. It has been shown that in acidic medium V/sup 3 +/ forms yellow complexes of the composition 1:1 with instability constants 2.2x10/sup -19/, 7.8x10/sup -11/, and 2.2x10/sup -12/, respectively. Complexes of V/sup 3 +/ with derivatives of salicylic acid can be used for determining V(3) content in the presence of V(4).

Phytochemical profile of Orthosiphon aristatus extracts after storage: Rosmarinic acid and other caffeic acid derivatives.

Science.gov (United States)

Chua, Lee Suan; Lau, Cher Haan; Chew, Chee Yung; Ismail, Nurul Izzati Mohd; Soontorngun, Nitnipa

2018-01-15

Orthosiphon aristatus (Blume) Miq. is a medicinal herb which is traditionally used for the treatment of diabetes and kidney diseases in South East Asia. Previous studies reported higher concentration of antioxidative phytochemicals, especially rosmarinic acid (ester of caffeic acid) and other caffeic acid derivatives in this plant extract than the other herbs such as rosemary and sage which are usually used as raw materials to produce rosmarinic acid supplement in the market. The phytochemical profile of O. aristatus was investigated at different storage durations for quality comparison. The phytochemicals were extracted from the leaves and stems of O. aristatus using a reflux reactor. The extracts were examined for total phenolic and flavonoid contents, as well as their antioxidant capacities, in terms of radical scavenging, metal chelating and reducing power. The phytochemical profiles were also analyzed by unsupervised principal component analysis and hierarchical cluster analysis, in relation to the factor of storage at 4 °C for 5 weeks. The leaf extract was likely to have more phytochemicals than stem extract, particularly caffeic acid derivatives including glycosylated and alkylated caffeic acids. This explains higher ratio of total phenolic content to total flavonoid content with higher antioxidant capacities for the leaf extracts. Rosmarinic acid dimer and salvianolic acid B appeared to be the major constituents, possibly contributing to the previously reported pharmacological properties. However, the phytochemical profiles were found changing, even though the extracts were stored in the refrigerator (4 °C). The change was significantly observed at the fifth week based on the statistical pattern recognition technique. O. aristatus could be a promising source of rosmarinic acid and its dimer, as well as salvianolic acid B with remarkably antioxidant properties. The phytochemical profile was at least stable for a month stored at 4 °C. It is likely to be

Oleanolic Acid and Its Derivatives: Biological Activities and Therapeutic Potential in Chronic Diseases

Directory of Open Access Journals (Sweden)

Taiwo Betty Ayeleso

2017-11-01

Full Text Available The increasing demand for natural products as an alternative therapy for chronic diseases has encouraged research into the pharmacological importance of bioactive compounds from plants. Recently, there has been a surge of interest in the therapeutic potential of oleanolic acid (OA in the prevention and management of chronic diseases. Oleanolic acid is a pentacyclic triterpenoid widely found in plants, including fruits and vegetables with different techniques and chromatography platforms being employed in its extraction and isolation. Several studies have demonstrated the potential therapeutic effects of OA on different diseases and their symptoms. Furthermore, oleanolic acid also serves as a framework for the development of novel semi-synthetic triterpenoids that could prove vital in finding therapeutic modalities for various ailments. There are recent advances in the design and synthesis of chemical derivatives of OA to enhance its solubility, bioavailability and potency. Some of these derivatives have also been therapeutic candidates in a number of clinical trials. This review consolidates and expands on recent reports on the biological effects of oleanolic acid from different plant sources and its synthetic derivatives as well as their mechanisms of action in in vitro and in vivo study models. This review suggests that oleanolic acid and its derivatives are important candidates in the search for alternative therapy in the treatment and management of chronic diseases.

Study of application properties of novel trisazo hetero bi-functional reactive dyes based on j-acid derivatives for cotton

International Nuclear Information System (INIS)

Mokhtari, Javad; Akbarzadeh, A; Phillips, D A S; Taylor, J A

2009-01-01

Three novel trisazo hetero bi-functional reactive dyes based on J-acid derivatives were prepared using the diazonium salt of [4-(4-sulphophenylazo-)-2,5-dimethylazobenzene-2-sulphonic acid] and a hetero bi-functional coupling component, derived from 1-hydroxy-6-aminonapthalene-3-sulphonic acid (J-acid), 1-hydroxy-6- methylaminonapthalene-3-sulphonic acid (methyl J-acid), and 1-hydroxy-6-aminonaphthalene-3,5-disulphonic acid (sulpho J-acid). On balance, the dye derived from sulpho J-acid displayed the most attractive set of technical properties, building up and fixing more efficiently than those derived from J-acid and methyl J-acid. In addition, the sulpho J-acid based dye offered better migration and, therefore, level dyeing and ease of wash off. (author)

Banana-shaped molecules derived from substituted isophthalic acids

Indian Academy of Sciences (India)

In this paper we present a review of five-rings banana-shaped molecules derived from isophthalic acids. This study deals with about a hundred compounds and most of them have not been published. By a combination of several linking groups and different selected substituents either on the outer rings or on the central core ...

Ion-pair high performance liquid chromatographic retention behavior of salicylic acid and its derivatives

Energy Technology Data Exchange (ETDEWEB)

Lee, K.W.; Chung, Y.S. [Chungbuk National University, Cheongju (Korea); Oh, S.K. [Handok Pharmaceuticals Co. Ltd., Chungbuk (Korea)

1999-06-01

The ion-pair high performance liquid chromatographic elution behavior of salicylic acid and its derivatives was studied with measuring capacity factor, k', changing the concentration of ion-pairing reagent (tetrabutylammonium chloride, TBACl) in mobile phase. As a result, it was found that k' of the samples increase at pH 7.2 as the TBACl concentration increase. The derivatives of salicylic acid were separated each other at an optimum mobile phase condition which was found from the observation of the retention behavior. The optimum mobile phase condition was methanol solution(MeOH:H{sub 2}O 30:70) containing 20 mM TBACl for the determination of salicylic acid and methanol solution (MeOH:H{sub 2}O 20:80) containing 40 mM TBACl for p-aminosalicylic acid at pH 7.2. The method has been applied for the analysis of the contents of salicylic acid derivatives in an aspirin tablet and a tuberculosis curing agent. 8 refs., 4 figs., 2 tabs.

Formation and Characterization of Self-Assembled Phenylboronic Acid Derivative Monolayers toward Developing Monosaccaride Sensing-Interface

Directory of Open Access Journals (Sweden)

Kwangnak Koh

2007-08-01

Full Text Available We designed and synthesized phenylboronic acid as a molecular recognitionmodel system for saccharide detection. The phenylboronic acid derivatives that haveboronic acid moiety are well known to interact with saccharides in aqueous solution; thus,they can be applied to a functional interface of saccharide sensing through the formation ofself-assembled monolayer (SAM. In this study, self-assembled phenylboronic acidderivative monolayers were formed on Au surface and carefully characterized by atomicforce microscopy (AFM, Fourier transform infrared reflection absorption spectroscopy(FTIR-RAS, surface enhanced Raman spectroscopy (SERS, and surface electrochemicalmeasurements. The saccharide sensing application was investigated using surface plasmonresonance (SPR spectroscopy. The phenylboronic acid monolayers showed goodsensitivity of monosaccharide sensing even at the low concentration range (1.0 × 10-12 M.The SPR angle shift derived from interaction between phenylboronic acid andmonosaccharide was increased with increasing the alkyl spacer length of synthesizedphenylboronic acid derivatives.

Shoot-derived abscisic acid promotes root growth.

Science.gov (United States)

McAdam, Scott A M; Brodribb, Timothy J; Ross, John J

2016-03-01

The phytohormone abscisic acid (ABA) plays a major role in regulating root growth. Most work to date has investigated the influence of root-sourced ABA on root growth during water stress. Here, we tested whether foliage-derived ABA could be transported to the roots, and whether this foliage-derived ABA had an influence on root growth under well-watered conditions. Using both application studies of deuterium-labelled ABA and reciprocal grafting between wild-type and ABA-biosynthetic mutant plants, we show that both ABA levels in the roots and root growth in representative angiosperms are controlled by ABA synthesized in the leaves rather than sourced from the roots. Foliage-derived ABA was found to promote root growth relative to shoot growth but to inhibit the development of lateral roots. Increased root auxin (IAA) levels in plants with ABA-deficient scions suggest that foliage-derived ABA inhibits root growth through the root growth-inhibitor IAA. These results highlight the physiological and morphological importance, beyond the control of stomata, of foliage-derived ABA. The use of foliar ABA as a signal for root growth has important implications for regulating root to shoot growth under normal conditions and suggests that leaf rather than root hydration is the main signal for regulating plant responses to moisture. © 2015 John Wiley & Sons Ltd.

Catalytic amino acid production from biomass-derived intermediates

KAUST Repository

Deng, Weiping

2018-04-30

Amino acids are the building blocks for protein biosynthesis and find use in myriad industrial applications including in food for humans, in animal feed, and as precursors for bio-based plastics, among others. However, the development of efficient chemical methods to convert abundant and renewable feedstocks into amino acids has been largely unsuccessful to date. To that end, here we report a heterogeneous catalyst that directly transforms lignocellulosic biomass-derived α-hydroxyl acids into α-amino acids, including alanine, leucine, valine, aspartic acid, and phenylalanine in high yields. The reaction follows a dehydrogenation-reductive amination pathway, with dehydrogenation as the rate-determining step. Ruthenium nanoparticles supported on carbon nanotubes (Ru/CNT) exhibit exceptional efficiency compared with catalysts based on other metals, due to the unique, reversible enhancement effect of NH3 on Ru in dehydrogenation. Based on the catalytic system, a two-step chemical process was designed to convert glucose into alanine in 43% yield, comparable with the well-established microbial cultivation process, and therefore, the present strategy enables a route for the production of amino acids from renewable feedstocks. Moreover, a conceptual process design employing membrane distillation to facilitate product purification is proposed and validated. Overall, this study offers a rapid and potentially more efficient chemical method to produce amino acids from woody biomass components.

MODERN INDICATORS DERIVED FROM VALUE CREATION AND DISCOUNTED

Directory of Open Access Journals (Sweden)

Cican Simona

2013-07-01

In this article, we will present the connection between discounted cash flow methods and the indicators derived from value creation, based on the business finance theory, which says that firm value will increase if projects with positive net present value are accepted, while it will be destroyed if projects with negative net present value are accepted.

Fatty acid and cholesterol profiles and hypocholesterolemic, atherogenic, and thrombogenic indices of table eggs in the retail market.

Science.gov (United States)

Attia, Youssef A; Al-Harthi, Mohammed A; Korish, Mohamed A; Shiboob, Mohamed M

2015-10-27

Eggs are an important source of food due to its favorable effects on human health derived from the protein, fats, minerals, vitamins and bioactive components. We studied the effects of source of eggs in the retail market on fatty acids, lipid profiles and antioxidant status in eggs. Eggs from four sources named A, B, C, and D in the retail market were collected to determine fatty acid, total lipid, and cholesterol profiles; hypocholesterolemic, atherogenic and thrombotic indices; antioxidant status (e.g., of malondialdehyde); and total antioxidant capacity in the whole edible parts of eggs (albumen + yolk) and egg yolk. Samples were collected four times and pooled over times to represent 5 and 10 samples per source for determinations of fatty acids and determinations of lipid profiles and antioxidant status, respectively. Fatty acid, total lipid, and cholesterol profiles; hypocholesterolemic, atherogenic and thrombotic indices; presence of malondialdehyde; and total antioxidant capacity in the whole edible parts of eggs and egg yolk showed significant differences (P ≥ 0.05) among different sources of eggs in retail market. Source D showed higher levels of saturated fatty acids (SFA) and linoleic and monounsaturated fatty acid (MUFA)/polyunsaturated fatty acid (PUFA) ratio but lower levels of MUFA and linolenic, arachidonic, eicosapentaeonic (EPA), decohexaenoic (DHA), and total ω9 fatty acids and lower unsaturated fatty acids (UFA)/SFA ratio. Similar trend was shown in fatty acids profiles of the whole edible parts of eggs. On the other hand, total cholesterol, low density lipoprotein (LDL), LDL/high density lipoprotein (HDL) ratio, and atherogenic and thrombogenic indices and total antioxidant capacity of source D were significantly higher than those of other source, but levels of hypocholesterolemic index, and malondialdehyde levels were lower for source D. Eggs in the retail market in Jeddah city, Saudi Arabia, from May to August 2015 showed a

Chiral gels derived from secondary ammonium salts of (1R,3S-(+-camphoric acid

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Tapas Kumar Adalder

2010-09-01

Full Text Available In order to have access to chiral gels, a series of salts derived from (1R,3S-(+-camphoric acid and various secondary amines were prepared based on supramolecular synthon rationale. Out of seven salts prepared, two showed moderate gelation abilities. The gels were characterized by differential scanning calorimetry, table top rheology, scanning electron microscopy, single crystal and powder X-ray diffraction. Structure property correlation based on X-ray diffraction techniques remain inconclusive indicating that some of the integrated part associated with the gelation phenomena requires a better understanding.

Opuntia ficus indica (L.) Fruit Extract as Natural Indicator in Acid-Base Titration

OpenAIRE

Manoj A. Suva

2014-01-01

In routine experiments synthetic indicators are the choice of acid base titrations. But there are some limitations like environmental pollution, availability and higher cost which leads to search for natural compounds as an acid base indicator was started. The present work highlights theexploit of the methanolic and aqueous extract of the fruit of Opuntia ficus indica plants as a natural acid base indicator in acid base titrations. Opuntia ficus indica plant was identified and fruits were was...

AMINOMETHANESULPHONIC ACIDS AND ITS N-DERIVATIVES ARE COMPONENTS OF N. GOODS BUFFERS

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R.E. Khoma

2015-11-01

Full Text Available On the basis of pH measuring the temperature dependence of the second ionization constant (pK2 are set for aminomethansulfonic acid (AMSA and its N-derivatives. It was found that the area of  effective buffering of AMSK and its N-benzyl derivative allows to maintain the pH of acid-compatible with life. The absolute values  of the coefficients in the equation pK2 = -Ai+ Bi/T for the aminosulfonic acids correlated with their molar masses. A simultaneous change in values  DpH /DT and Bicoefficient for the studied acids QSAR method are stayed. The values  of the distribution coefficients in the octanol – water (Pow and molar refraction are calculated. In the future the data obtained in this study will be used to predict the physical, chemical and toxicological properties of the compounds studied.

Caffeic acid derivative from Clinopodium umbrosum

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M. Esfahanizadeh

2017-11-01

Full Text Available Background and objectives: Plants of genus Clinopodium have been used in different cultures as traditional medicines.Due to theimportance of medicinal properties of the genus Clinopodium, C. umbrosum was selected for phytochemical analysis along with evaluation of its antioxidant property. Methods: The aerial parts of C. umbrosum were extracted with petroleum ether, chloroform, and methanol. Later, the methanol extract was fractionated via solid phase extraction and reversed phase high performance liquid chromatography. Consequently, structure of the isolated compound was analyzed through spectral analysis of 1D and 2D NMR data. Besides, the essential oil of C. umbrosum achieved through hydrodistillation was analyzed via gas chromatography-mass spectrometry (GC-MS. Additionally, the antioxidant property of C. umbrosum methanol extracttogether with its phenolics and flavonoids content were assessed. Results: Structure elucidation of the purified compound revealed presence of a caffeic acid derivative in C. umbrosum methanol extract. GC-MS analysis of the essential oil showed limonene, acetophenone, palmitic acid and phytol as the most frequent components of the essential oil. Moreover, the RC50 value for free radical scavenging activity of  the methanol extract was determined as 38.52 µg/mL and values for the total phenolics and flavonoids contact were calculated as 5.14 g gallic acid equivalent and 4.25 g quercetin equivalent per 100 g of dried plant material, respectively.  Conclusion: Overall, the present study was the first report on the phytochemical analysis of C. umbrosum whichrevealed presence of rosmarinic acid as the main component of the methanol extract with prominent antioxidant activity.

A triazole derivative as a new acid-base indicator

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Volkan Numan Bulut

2010-12-01

Full Text Available In this study a new pH indicator, 3-benzyl-4-p-nitrobenzylidenamino-4,5-dihydro-1,2,4-triazole-5-on (BPNBAT, soluble in acetonitrile:water (1:4, was developed. The estimation of pH is possible either from the position of the absorption maxima or from the absorbance intensity at a constant wavelength. This feature allowed us to determine the basic transition range of the medium because BPNBAT is colorless at pH lower than 8.5 and showed strong yellow-green color with high extinction coefficient in the pH range of 8.5–10.1. pKa, pH at equivalent point and the molar absorptivity (in the aqueous medium at 380 nm of BPNBAT are determined as 9.3, 8.3 and 8.8 x 103 L.mol-1.cm-1, respectively. The color change at the transition range can be attributed to the resonance structures of BPNBAT. The triazole compound was compared with thymolphthalein for accuracy test.

Modification of oligo-Ricinoleic Acid and Its Derivatives with 10-Undecenoic Acid via Lipase-Catalyzed Esterification

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M. Claudia Montiel

2012-04-01

Full Text Available Lipases were employed under solvent-free conditions to conjugate oligo-ricinoleic acid derivatives with 10-undecenoic acid, to incorporate a reactive terminal double bond into the resultant product. First, undecenoic acid was covalently attached to oligo-ricinoleic acid using immobilized Candida antarctica lipase (CAL at a 30% yield. Thirty percent conversion also occurred for CAL-catalyzed esterification between undecenoic acid and biocatalytically-prepared polyglycerol polyricinoleate (PGPR, with attachment of undecenoic acid occurring primarily at free hydroxyls of the polyglycerol moiety. The synthesis of oligo-ricinoleyl-, undecenoyl- structured triacylglycerols comprised two steps. The first step, the 1,3-selective lipase-catalyzed interesterification of castor oil with undecenoic acid, occurred successfully. The second step, the CAL-catalyzed reaction between ricinoleyl-, undecenoyl structured TAG and ricinoleic acid, yielded approximately 10% of the desired structured triacylglycerols (TAG; however, a significant portion of the ricinoleic acid underwent self-polymerization as a side-reaction. The employment of gel permeation chromatography, normal phase HPLC, NMR, and acid value measurements was effective for characterizing the reaction pathways and products that formed.

Production of ethoxylated fatty acids derived from Jatropha non-edible oil as a nonionic fat-liquoring agent.

Science.gov (United States)

El-Shattory, Y; Abo-Elwafa, Ghada A; Aly, Saadia M; Nashy, El-Shahat H A

2012-01-01

Natural fatty derivatives (oleochemicals) have been used as intermediate materials in several industries replacing the harmful and expensive petrochemicals. Fatty ethoxylates are one of these natural fatty derivatives. In the present work Jatropha fatty acids were derived from the non edible Jatropha oil and used as the fat source precursor. The ethoxylation process was carried out on the derived fatty acids using a conventional cheap catalyst (K₂CO₃) in order to obtain economically and naturally valuable non-ionic surfactants. Ethoxylation reaction was proceeded using ethylene oxide gas in the presence of 1 or 2% K₂CO₃ catalyst at 120 and 145°C for 5, 8 and 12 hours. The prepared products were evaluated for their chemical and physical properties as well as its application as non- ionic fat-liquoring agents in leather industry. The obtained results showed that the number of ethylene oxide groups introduced in the fatty acids as well as their EO% increased as the temperature and time of the reaction increased. The highest ethoxylation number was obtained at 145°C for 8 hr. Also, the prepared ethoxylated products were found to be effective fat-liquors with high HLB values giving stable oil in water emulsions. The fat-liquored leather led to an improvement in its mechanical properties such as tensile strength and elongation at break. In addition, a significant enhancement in the texture of the treated leather by the prepared fat-liquors as indicated from the scanning electron microscope (SEM) images was observed.

Synthesis of azido derivatives of mucobromic acid | D. Jumbam ...

African Journals Online (AJOL)

Mucobromic acid is a highly reactive multicentered molecule. It was converted to its corresponding but unstable diazido derivative by reaction with two equivalents of sodium azide. The resultant 3,4-diazido-5-hydroxyfuran-2(5H)-one was obtained in moderate yield (42%) but decomposed readily even at low temperatures.

Amino acid derivatives are substrates or non-transported inhibitors of the amino acid transporter PAT2 (slc36a2).

Science.gov (United States)

Edwards, Noel; Anderson, Catriona M H; Gatfield, Kelly M; Jevons, Mark P; Ganapathy, Vadivel; Thwaites, David T

2011-01-01

The H(+)-coupled amino acid transporter PAT2 (SLC36A2) transports the amino acids proline, glycine, alanine and hydroxyproline. A physiological role played by PAT2 in amino acid reabsorption in the renal proximal tubule is demonstrated by mutations in SLC36A2 that lead to an iminoglycinuric phenotype (imino acid and glycine uria) in humans. A number of proline, GABA and tryptophan derivatives were examined to determine if they function either as transported substrates or non-transported inhibitors of PAT2. The compounds were investigated following heterologous expression of rat PAT2 in Xenopus laevis oocytes. PAT2 function was characterised by: radiotracer uptake and competition (cis-inhibition) studies; radiotracer efflux and trans-stimulation; and measurement of substrate-induced positive inward current by two-electrode voltage-clamp. In general, the proline derivatives appeared to be transported substrates and the relative ability to induce current flow was closely related to the inhibitory effects on PAT2-mediated l-[(3)H]proline uptake. In contrast, certain heterocyclic GABA derivatives (e.g. l-pipecolic acid) were translocated only slowly. Finally, the tryptophan derivatives inhibited PAT2 function but did not undergo transport. l-Proline uptake was inhibited by 5-hydroxy-l-tryptophan (IC(50) 1.6±0.4mM), α-methyl-d,l-tryptophan (3.5±1.5mM), l-tryptophan, 1-methyl-l-tryptophan and indole-3-propionic acid. Although neither 5-hydroxy-l-tryptophan nor α-methyl-d,l-tryptophan were able to elicit inward current in PAT2-expressing oocytes both reduced the current evoked by l-proline. 5-Hydroxy-l-tryptophan and α-methyl-d,l-tryptophan were unable to trans-stimulate l-proline efflux from PAT2-expressing oocytes, confirming that the two compounds act as non-transported blockers of PAT2. These two tryptophan derivatives should prove valuable experimental tools in future investigations of the physiological roles of PAT2. Copyright © 2010 Elsevier B.V. All rights

Spin labeled amino acid nitrosourea derivatives--synthesis and antitumour activity.

Science.gov (United States)

Zheleva, A; Raikov, Z; Ilarionova, M; Todorov, D

1995-01-01

The synthesis of three spin labeled derivatives of N-[N'-(chloroethyl)-N'-nitrosocarbamoyl] amino acids is reported. The new nitrosoureas are obtained by condensation of the corresponding N-[N'-(2-chloroethyl)-N'-nitrosocarbamoyl] amino acid with 2,2,6,6-tetramethyl-1-oxyl-4-aminopiperidine using dicyclohexylcarbodiimide. Their chemical structures are confirmed by elemental analysis, IR, MS, and EPR spectroscopy. All newly synthesized compounds showed high antitumour activity against the lymphoid leukemia L1210 in BDF1 mice.

Antioxidant and cytotoxic activity of mono- and bissalicylic acid derivatives

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Đurendić Evgenija A.

2014-01-01

Full Text Available A simple synthesis of mono- and bis-salicylic acid derivatives 1-10 by the transesterification of methyl salicylate (methyl 2-hydroxybenzoate with 3-oxapentane-1,5-diol, 3,6- dioxaoctane-1,8-diol, 3,6,9-trioxaundecane-1,11-diol, propane-1,2-diol or 1-aminopropan- 2-ol in alkaline conditions is reported. All compounds were tested in vitro on three malignant cell lines (MCF-7, MDA-MB-231, PC-3 and one non-tumor cell line (MRC- 5. Strong cytotoxicity against prostate PC-3 cancer cells expressed compounds 3, 4, 6, 9 and 10, all with the IC50 less than 10 μmol/L, which were 11-27 times higher than the cytotoxicity of antitumor drug doxorubicin. All tested compounds were not toxic against the non-tumor MRC-5 cell line. Antioxidant activity of the synthesized derivatives was also evaluated. Compounds 2, 5 and 8 were better OH radical scavengers than commercial antioxidants BHT and BHA. The synthesized compounds showed satisfactory scavenger activity, which was studied by QSAR modeling. A good correlation between the experimental variables IC50 DPPH and IC50 OH and MTI (molecular topological indices molecular descriptors and CAA (accessible Connolly solvent surface area for the new compounds 1, 3, and 5 was observed.

Environmental Indicator Principium with Case References to Agricultural Soil, Water, and Air Quality and Model-Derived Indicators.

Science.gov (United States)

Zhang, T Q; Zheng, Z M; Lal, R; Lin, Z Q; Sharpley, A N; Shober, A L; Smith, D; Tan, C S; Van Cappellen, P

2018-03-01

Environmental indicators are powerful tools for tracking environmental changes, measuring environmental performance, and informing policymakers. Many diverse environmental indicators, including agricultural environmental indicators, are currently in use or being developed. This special collection of technical papers expands on the peer-reviewed literature on environmental indicators and their application to important current issues in the following areas: (i) model-derived indicators to indicate phosphorus losses from arable land to surface runoff and subsurface drainage, (ii) glutathione-ascorbate cycle-related antioxidants as early-warning bioindicators of polybrominated diphenyl ether toxicity in mangroves, and (iii) assessing the effectiveness of using organic matrix biobeds to limit herbicide dissipation from agricultural fields, thereby controlling on-farm point-source pollution. This introductory review also provides an overview of environmental indicators, mainly for agriculture, with examples related to the quality of the agricultural soil-water-air continuum and the application of model-derived indicators. Current knowledge gaps and future lines of investigation are also discussed. It appears that environmental indicators, particularly those for agriculture, work efficiently at the field, catchment, and local scales and serve as valuable metrics of system functioning and response; however, these indicators need to be refined or further developed to comprehensively meet community expectations in terms of providing a consistent picture of relevant issues and/or allowing comparisons to be made nationally or internationally. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Synthesis and characterization of polyesters derived from glycerol and phthalic acid

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Danilo Hansen Guimarães

2007-09-01

Full Text Available The production of polyester via polycondensation between glycerol and phthalic acid using dibutyltin dilaurate is reported. Three glycerol:phthalic acid molar ratio used for the bulk polymerization were: 2:2; 2:3 and 2:4. FTIR confirmed the esterification of glycerol by the acid for all the polymers. DSC indicated no crystallinity, although the XRD plots indicate a very incipient crystallinity for the polymers containing higher amounts of phthalic anhydride. Scanning electron microscopy results indicates high homogeneity for all the polymers prepared.

Synthesis of novel 68Ga-labeled amino acid derivatives for positron emission tomography of cancer cells

International Nuclear Information System (INIS)

Shetty, Dinesh; Jeong, Jae Min; Ju, Chang Hwan; Lee, Yun-Sang; Jeong, Seo Young; Choi, Jae Yeon; Yang, Bo Yeun

2010-01-01

Objectives: We developed amino acid derivatives of 1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (DO2A) and 1,4,7,10-tetraazacyclododecane-1,4,7,-triacetic acid (DO3A) that can be labeled with 68 Ga, and we investigated their basic biological properties. Materials and methods: Alanine derivatives of DO2A and DO3A were synthesized by regiospecific nucleophilic attack of DO2tBu and DO3tBu on the β-position of Boc-L-serine-β-lactone, followed by acid hydrolysis. Also, homoalanine derivatives were synthesized by reacting with the protected bromo derivative of homoalanine, which was synthesized from N-Cbz-L-homoserine lactone. Further catalytic reduction and acid cleavage of protected groups resulted in the required products. All derivatives were labeled with 68 Ga. Cell uptake assays were carried out in Hep3B (human hepatoma) and U87MG (human glioma) cell lines at 37 o C. Positron emission tomography (PET) imaging studies were performed using balb/c mice xenografted with CT-26 (mouse colon cancer). Results: All compounds were labeled with >97% efficiency. According to in vitro studies, the labeled amino acid derivatives showed significantly greater uptakes than the control ( 68 Ga 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) in cancer cells. Small animal PET images for labeled compounds showed high tumor uptake, as well as kidney and bladder uptakes, at 30 min postinjection. 68 Ga-DO3A-homoalanine showed the highest standardized uptake value ratio (3.9±0.3), followed by 68 Ga-DO2A-alanine (3.1±0.2), 68 Ga-DO3A-alanine (2.8±0.2) and 68 Ga-DO2A-homoalanine (2.3±0.2). Conclusion: These derivatives were found to have high labeling efficiencies, high stabilities, high tumor cell uptakes, high tumor/nontumor xenograft uptakes and low nonspecific uptake in normal organs, except for the kidneys. However, the uptake mechanism of these derivatives remains unclear, and uptake via specific amino acid transporters needs to be demonstrated.

Analysis of naphthenic acid mixtures as pentafluorobenzyl derivatives by gas chromatography-electron impact mass spectrometry.

Science.gov (United States)

Gutierrez-Villagomez, Juan Manuel; Vázquez-Martínez, Juan; Ramírez-Chávez, Enrique; Molina-Torres, Jorge; Trudeau, Vance L

2017-01-01

In this study, we report for the first time the efficiency of pentafluorobenzyl bromide (PFBBr) for naphthenic acid (NA) mixtures derivatization, and the comparison in the optimal conditions to the most common NAs derivatization reagents, BF 3 /MeOH and N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA). Naphthenic acids are carboxylic acid mixtures of petrochemical origin. These compounds are important for the oil industry because of their corrosive properties, which can damage oil distillation infrastructure. Moreover, NAs are commercially used in a wide range of products such as paint and ink driers, wood and fabric preservatives, fuel additives, emulsifiers, and surfactants. Naphthenic acids have also been found in sediments after major oils spills in the United States and South Korea. Furthermore, the toxicity of the oil sands process-affected water (OSPW), product of the oil sands extraction activities in Canada's oil sands, has largely been attributed to NAs. One of the main challenges for the chromatographic analysis of these mixtures is the resolution of the components. The derivatization optimization was achieved using surface response analysis with molar ratio and time as factors for derivatization signal yield. After gas chromatography-electron impact mass spectrometry (GC/EIMS) analysis of a mixture of NA standards, it was found that the signal produced by PFB-derivatives was 2.3 and 1.4 times higher than the signal produced by methylated and MTBS-derivatives, respectively. The pentafluorobenzyl derivatives have a characteristic fragment ion at 181m/z that is diagnostic for the differentiation of carboxylic and non-carboxylic acid components within mixtures. In the analysis of a Sigma and a Merichem derivatized oil extract NA mixtures, it was found that some peaks lack the characteristic fragment ion; therefore they are not carboxylic acids. Open column chromatography was used to obtain a hexane and a methanol fraction of the Sigma and

Flower extract as an improvised indicator in acid – base titration ...

African Journals Online (AJOL)

Different flowers were collected and the extracts were tested for indicator properties in acidic and basic solutions. The results showed different colour changes in alkaline and colourless in acid solutions. When used in acid-base titration, the end points colours and the average titre values obtained matched with that of ...

Direct catalytic conversion of brown seaweed-derived alginic acid to furfural using 12-tungstophosphoric acid catalyst in tetrahydrofuran/water co-solvent

International Nuclear Information System (INIS)

Park, Geonu; Jeon, Wonjin; Ban, Chunghyeon; Woo, Hee Chul; Kim, Do Heui

2016-01-01

Highlights: • Furfural was produced by catalytic conversion of macroalgae-derived alginic acid. • 12-Tungstophosphoric acid (H_3PW_1_2O_4_0) showed remarkable catalytic performance. • Tetrahydrofuran (THF) as a reaction medium significantly enhanced production of furfural. - Abstract: Furfural, a biomass-derived platform chemical, was produced by acid-catalyzed reaction of alginic acid extracted from brown seaweed. Three acid catalysts, H_2SO_4, Amberlyst15 and 12-tungstophosphoric acid (H_3PW_1_2O_4_0), were compared to evaluate their catalytic performance for the alginic acid conversion. The H_3PW_1_2O_4_0 catalyst showed the highest catalytic activity, yielding the maximum furfural yield (33.8%) at 180 °C for 30 min in tetrahydrofuran/water co-solvent. Higher reaction temperature promoted the conversion of alginic acid to furfural, but the transformation of furfural to humin was also accelerated. To our knowledge, this is the highest furfural yield among studies about the direct catalytic conversion of alginic acid. Furthermore, products distribution with time-on-stream was investigated in detail, which led us to propose a reaction pathway.

Synthesis and pharmacology of N-alkylated derivatives of the excitotoxin ibotenic acid

DEFF Research Database (Denmark)

Madsen, U; Dumpis, M A; Bräuner-Osborne, Hans

1998-01-01

Three amino-alkylated derivatives of the naturally occurring excitatory amino acid (EAA) receptor agonist ibotenic acid (Ibo) have been synthesized and tested pharmacologically. N-Methyl-Ibo (1a) and N-ethyl-Ibo (1b) were shown to be agonists at NMDA receptors (EC50 = 140 and 320 micro......-c and the potent NMDA agonist 2-amino-2-(3-hydroxy-5-methyl-4-isoxazolyl)acetic acid (AMAA) in order to elucidate the observed structure-activity data....

Gallic acid-based indanone derivative interacts synergistically with tetracycline by inhibiting efflux pump in multidrug resistant E. coli.

Science.gov (United States)

Dwivedi, Gaurav Raj; Tiwari, Nimisha; Singh, Aastha; Kumar, Akhil; Roy, Sudeep; Negi, Arvind Singh; Pal, Anirban; Chanda, Debabrata; Sharma, Ashok; Darokar, Mahendra P

2016-03-01

The purpose of the present study was to study the synergy potential of gallic acid-based derivatives in combination with conventional antibiotics using multidrug resistant cultures of Escherichia coli. Gallic acid-based derivatives significantly reduced the MIC of tetracycline against multidrug resistant clinical isolate of E. coli. The best representative, 3-(3',4,'5'-trimethoxyphenyl)-4,5,6-trimethoxyindanone-1, an indanone derivative of gallic acid, was observed to inhibit ethidium bromide efflux and ATPase which was also supported by in silico docking. This derivative extended the post-antibiotic effect and decreased the mutation prevention concentration of tetracycline. This derivative in combination with TET was able to reduce the concentration of TNFα up to 18-fold in Swiss albino mice. This derivative was nontoxic and well tolerated up to 300 mg/kg dose in subacute oral toxicity study in mice. This is the first report of gallic acid-based indanone derivative as drug resistance reversal agent acting through ATP-dependent efflux pump inhibition.

Docking of oxalyl aryl amino benzoic acid derivatives into PTP1B

Science.gov (United States)

Verma, Neelam; Mittal, Minakshi; Verma, Raman kumar

2008-01-01

Protein Tyrosine Phosphatases (PTPs) that function as negative regulators of the insulin signaling cascade have been identified as novel targets for the therapeutic enhancement of insulin action in insulin resistant disease states. Reducing Protein Tyrosine Phosphatase1B (PTP1B) abundance not only enhances insulin sensitivity and improves glucose metabolism but also protects against obesity induced by high fat feeding. PTP1B inhibitors such as Formylchromone derivatives, 1, 2-Naphthoquinone derivatives and Oxalyl aryl amino benzoic derivatives may eventually find an important clinical role as insulin sensitizers in the management of Type-II Diabetes and metabolic syndrome. We have carried out docking of modified oxalyl aryl amino benzoic acid derivatives into three dimensional structure of PTP1B using BioMed CAChe 6.1. These compounds exhibit good selectivity for PTP1B over most of phosphatases in selectivity panel such as SHP-2, LAR, CD45 and TCPTP found in literature. This series of compounds identified the amino acid residues such as Gly220 and Arg221 are important for achieving specificity via H-bonding interactions. Lipophilic side chain of methionine in modified oxalyl aryl amino benzoic acid derivative [1b (a2, b2, c1, d)] lies in closer vicinity of hydrophobic region of protein consisted of Meth258 and Phe52 in comparison to active ligand. Docking Score in [1b (a2, b2, c1, d)] is -131.740Kcal/mol much better than active ligand score -98.584Kcal/mol. This information can be exploited to design PTP1B specific inhibitors. PMID:19238234

Salicylic acid metabolites and derivatives inhibit CDK activity: Novel insights into aspirin's chemopreventive effects against colorectal cancer

Science.gov (United States)

Dachineni, Rakesh; Kumar, D. Ramesh; Callegari, Eduardo; Kesharwani, Siddharth S.; Sankaranarayanan, Ranjini; Seefeldt, Teresa; Tummala, Hemachand; Bhat, G. Jayarama

2017-01-01

Aspirin's potential as a drug continues to be evaluated for the prevention of colorectal cancer (CRC). Although multiple targets for aspirin and its metabolite, salicylic acid, have been identified, no unifying mechanism has been proposed to clearly explain its chemopreventive effects. Our goal here was to investigate the ability of salicylic acid metabolites, known to be generated through cytochrome P450 (CYP450) enzymes, and its derivatives as cyclin dependent kinase (CDK) inhibitors to gain new insights into aspirin's chemopreventive actions. Using in vitro kinase assays, for the first time, we demonstrate that salicylic acid metabolites, 2,3-dihydroxy-benzoic acid (2,3-DHBA) and 2,5-dihydroxybenzoic acid (2,5-DHBA), as well as derivatives 2,4-dihydroxybenzoic acid (2,4-DHBA), 2,6-dihydroxybenzoic acid (2,6-DHBA), inhibited CDK1 enzyme activity. 2,3-DHBA and 2,6-DHBA did not inhibit CDK2 and 4; however, both inhibited CDK-6 activity. Interestingly, another derivative, 2,4,6-trihydroxybenzoic acid (2,4,6-THBA) was highly effective in inhibiting CDK1, 2, 4 and 6 activity. Molecular docking studies showed that these compounds potentially interact with CDK1. Immunoblotting experiments showed that aspirin acetylated CDK1, and pre-incubation with salicylic acid and its derivatives prevented aspirin-mediated CDK1 acetylation, which supported the data obtained from molecular docking studies. We suggest that intracellularly generated salicylic acid metabolites through CYP450 enzymes within the colonic epithelial cells, or the salicylic acid metabolites generated by gut microflora may significantly contribute to the preferential chemopreventive effect of aspirin against CRC through inhibition of CDKs. This novel hypothesis and mechanism of action in aspirin's chemopreventive effects opens a new area for future research. In addition, structural modification to salicylic acid derivatives may prove useful in the development of novel CDK inhibitors in cancer prevention and

Structure Properties and Mechanisms of Action of Naturally Originated Phenolic Acids and Their Derivatives against Human Viral Infections.

Science.gov (United States)

Wu, Yi-Hang; Zhang, Bing-Yi; Qiu, Li-Peng; Guan, Rong-Fa; Ye, Zi-Hong; Yu, Xiao-Ping

2017-01-01

A great effort has been made to develop efficacious antiviral drugs, but many viral infections are still lack of efficient antiviral therapies so far. The related exploration of natural products to fight viruses has been raised in recent years. Natural compounds with structural diversity and complexity offer a great chance to find new antiviral agents. Particularly, phenolic acids have attracted considerable attention owing to their potent antiviral abilities and unique mechanisms. The aim of this review is to report new discoveries and updates pertaining to antiviral phenolic acids. The relevant references on natural phenolic acids were searched. The antiviral phenolic acids were classified according to their structural properties and antiviral types. Meanwhile, the antiviral characteristics and structure-activity relationships of phenolic acids and their derivatives were summarized. The review finds that natural phenolic acids and their derivatives possessed potent inhibitory effects on multiple virus in humans such as human immunodeficiency virus, hepatitis C virus, hepatitis B virus, herpes simplex virus, influenza virus and respiratory syncytial virus. In particular, caffeic acid/gallic acid and their derivatives exhibited outstanding antiviral properties by a variety of modes of action. Naturally derived phenolic acids especially caffeic acid/gallic acid and their derivatives may be regarded as novel promising antiviral leads or candidates. Additionally, scarcely any of these compounds has been used as antiviral treatment in clinical practice. Therefore, these phenolic acids with diverse skeletons and mechanisms provide us an excellent resource for finding novel antiviral drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Assessment of antitumoral and antimicrobial effects of a maslinic acid derivative

Directory of Open Access Journals (Sweden)

Ioana Z. Pavel

2016-12-01

Full Text Available INTRODUCTION Maslinic acid, a naturally occurring triterpene, has been reported to possess several therapeutic effects including antioxidant, anti-inflammatory and antiparasitic properties. Structural changes of the compound led to the development of new derivatives in order to expand the spectrum of activities. OBJECTIVES AND BACKGROUND The present study was purposed to assess the in vitro antitumoral and antibacterial effects of a maslinic acid derivative, namely benzyl (2α, 3β 2,3-diacetoxy-olean-12- en-28-amide (EM2. MATERIALS AND METHODS Four compound concentrations (12.5, 25, 50 and 100 µM were evaluated for their cytotoxic effect on A375 human melanoma and B164A5 murine melanoma cell lines using the MTT assay. Furthermore, EM2 was tested on ten bacterial strains by means of agar disk diffusion method with the assessment of the inhibition zone diameters at 24h period of time. RESULTS EM2 elicited a dose-dependent cytotoxic effect on both melanoma cell lines. Regarding the antibacterial activity, EM2 determined a significant growth inhibition on Streptococcus pyogenes (20 ± 0.26 mm and Staphylococcus aureus (13 ± 0.19 mm. CONCLUSIONS The tested maslinic acid derivative is a promising antitumoral agent against skin cancer and antimicrobial agent against cocci bacteria. Graphical abstract: EM2 in vitro effects

Synthesis of α,ω-polyfluorinated α-amino acid derivatives and δ,δ-difluoronorvaline.

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Ulbrich, Dirk; Daniliuc, Constantin G; Haufe, Günter

2016-03-07

Intending to synthesize ω,ω-difluoroalkyl amino acid derivatives by oxidative desulfurization-fluorination reactions of suitable arylthio-2-phthalimido butanoates and pentanoates, in addition to small amounts of the target products, mainly α,ω-polyfluorinated amino acid derivatives were formed by additional sulfur-assisted α-fluorination. This novel structural motif was verified spectroscopically as well as by X-ray analysis. A plausible mechanism of formation is suggested. Using a different approach, δ,δ-difluoronorvaline hydrochloride was synthesized with at least 36% enantiomeric excess via deoxofluorination of the corresponding aldehyde.

Distinguishing plant population and variety with UAV-derived vegetation indices

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Oakes, Joseph; Balota, Maria

2017-05-01

Variety selection and seeding rate are two important choice that a peanut grower must make. High yielding varieties can increase profit with no additional input costs, while seeding rate often determines input cost a grower will incur from seed costs. The overall purpose of this study was to examine the effect that seeding rate has on different peanut varieties. With the advent of new UAV technology, we now have the possibility to use indices collected with the UAV to measure emergence, seeding rate, growth rate, and perhaps make yield predictions. This information could enable growers to make management decisions early in the season based on low plant populations due to poor emergence, and could be a useful tool for growers to use to estimate plant population and growth rate in order to help achieve desired crop stands. Red-Green-Blue (RGB) and near-infrared (NIR) images were collected from a UAV platform starting two weeks after planting and continued weekly for the next six weeks. Ground NDVI was also collected each time aerial images were collected. Vegetation indices were derived from both the RGB and NIR images. Greener area (GGA- the proportion of green pixels with a hue angle from 80° to 120°) and a* (the average red/green color of the image) were derived from the RGB images while Normalized Differential Vegetative Index (NDVI) was derived from NIR images. Aerial indices were successful in distinguishing seeding rates and determining emergence during the first few weeks after planting, but not later in the season. Meanwhile, these aerial indices are not an adequate predictor of yield in peanut at this point.

Bioinspired bioadhesive polymers: dopa-modified poly(acrylic acid) derivatives.

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Laulicht, Bryan; Mancini, Alexis; Geman, Nathanael; Cho, Daniel; Estrellas, Kenneth; Furtado, Stacia; Hopson, Russell; Tripathi, Anubhav; Mathiowitz, Edith

2012-11-01

The one-step synthesis and characterization of novel bioinspired bioadhesive polymers that contain Dopa, implicated in the extremely adhesive byssal fibers of certain gastropods, is reported. The novel polymers consist of combinations of either of two polyanhydride backbones and one of three amino acids, phenylalanine, tyrosine, or Dopa, grafted as side chains. Dopa-grafted hydrophobic backbone polymers exhibit as much as 2.5 × the fracture strength and 2.8 × the tensile work of bioadhesion of a commercially available poly(acrylic acid) derivative as tested on live, excised, rat intestinal tissue. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electrochemical Coupling of Biomass-Derived Acids: New C8 Platforms for Renewable Polymers and Fuels.

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Wu, Linglin; Mascal, Mark; Farmer, Thomas J; Arnaud, Sacha Pérocheau; Wong Chang, Maria-Angelica

2017-01-10

Electrolysis of biomass-derived carbonyl compounds is an alternative to condensation chemistry for supplying products with chain length >C 6 for biofuels and renewable materials production. Kolbe coupling of biomass-derived levulinic acid is used to obtain 2,7-octanedione, a new platform molecule only two low process-intensity steps removed from raw biomass. Hydrogenation to 2,7-octanediol provides a chiral secondary diol largely unknown to polymer chemistry, whereas intramolecular aldol condensation followed by hydrogenation yields branched cycloalkanes suitable for use as high-octane, cellulosic gasoline. Analogous electrolysis of an itaconic acid-derived methylsuccinic monoester yields a chiral 2,5-dimethyladipic acid diester, another underutilized monomer owing to lack of availability. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Oxidation of phenolic acid derivatives by soil and its relevance to allelopathic activity.

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Ohno, T

2001-01-01

Previous studies have suggested that phenolic acids from legume green manures may contribute to weed control through allelopathy. The objectives of this study were to investigate the oxidation reactions of phenolic acids in soil and to determine the subsequent effects of oxidation upon phytotoxicity. Soils were reacted for 18 h with 0.25 mmol L(-1) benzoic and cinnamic acid derivative solutions and Mn release from the suspension was used as a marker for phenolic acid oxidation. The extent of oxidation in soil suspensions was in the order of 3,4dihydroxy- > 4-hydroxy-3-methoxy- > 4-hydroxy-approximately 2-hydroxy-substituted benzoic and cinnamic acids. The same ranking was observed for cyclic voltammetry peak currents of the cinnamic acid derivatives. This suggests that the oxidation of phenolic acids is controlled by the electron transfer step from the sorbed phenolic acid to the metal oxide. A bioassay experiment showed that the 4-hydroxy-, 4-hydroxy-3-methoxy-, and 3,4-dihydroxy-substituted cinnamic acids were bioactive at 0.25 mmol L(-1) concentration. Reaction with soil for 18 h resulted in the elimination of bioactivity of these three cinnamic acids at the 5% significance level. The oxidative reactivity of phenolic acids may limit the potential of allelopathy as a component of an integrated weed management system. However, the initial phytotoxicity after soil incorporation may coincide with the early, critical stage of weed emergence and establishment, so that allelopathic phenolic acids may still play a role in weed management despite their reactivity in soil systems.

Anacardic acid derivatives from Brazilian propolis and their antibacterial activity

Energy Technology Data Exchange (ETDEWEB)

Silva, M.S.S.; Lima, S.G. de; Lopes, J.A.D.; Chaves, M.H.; Cito, A.M.G.L. [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil). Dept. de Quimica]. E-mail: gracito@ufpi.br; Oliveira, E.H. [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil). Dept. de Microbiologia e Parasitologia; Reis, F.A.M. [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Inst. de Quimica

2008-07-01

Propolis is a sticky, gummy, resinous substance collected by honeybees (Apis mellifera L.) from various plant sources, which has excellent medicinal properties. This paper describes the isolation and identification of triterpenoids and anacardic acid derivatives from Brazilian propolis and their antibacterial activity. Their structures were elucidated by {sup 1}H and {sup 13}C NMR, including uni- and bidimensional techniques; in addition, comparisons were made with data from academic literature. These compounds were identified as: cardanols (1a + 1b), cardols (2a + 2b), mono ene anacardic acid (3), alpha-amirine (4), beta-amirine (5), cycloartenol (6), 24-methylene-cycloartenol (7) and lupeol (8). The determination of the position of the double bond after a reaction with Dimethyl disulfide (DMDS) is described for the phenol derivatives. The ethanolic extract was tested in vitro for antimicrobial activity by using the disc diffusion method and it showed significant results against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Shigella spp. (author)

Anacardic acid derivatives from Brazilian propolis and their antibacterial activity

International Nuclear Information System (INIS)

Silva, M.S.S.; Lima, S.G. de; Lopes, J.A.D.; Chaves, M.H.; Cito, A.M.G.L.; Oliveira, E.H.; Reis, F.A.M.

2008-01-01

Propolis is a sticky, gummy, resinous substance collected by honeybees (Apis mellifera L.) from various plant sources, which has excellent medicinal properties. This paper describes the isolation and identification of triterpenoids and anacardic acid derivatives from Brazilian propolis and their antibacterial activity. Their structures were elucidated by 1 H and 13 C NMR, including uni- and bidimensional techniques; in addition, comparisons were made with data from academic literature. These compounds were identified as: cardanols (1a + 1b), cardols (2a + 2b), mono ene anacardic acid (3), alpha-amirine (4), beta-amirine (5), cycloartenol (6), 24-methylene-cycloartenol (7) and lupeol (8). The determination of the position of the double bond after a reaction with Dimethyl disulfide (DMDS) is described for the phenol derivatives. The ethanolic extract was tested in vitro for antimicrobial activity by using the disc diffusion method and it showed significant results against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Shigella spp. (author)

Two New Cholic Acid Derivatives from the Marine Ascidian-Associated Bacterium Hasllibacter halocynthiae

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Sung Hun Kim

2012-10-01

Full Text Available The investigation of secondary metabolites in liquid cultures of a recently discovered marine bacterium, Hasllibacter halocynthiae strain KME 002T, led to the isolation of two new cholic acid derivatives. The structures of these compounds were determined to be 3,3,12-trihydroxy-7-ketocholanic acid (1 and 3,3,12-trihydroxy-7-deoxycholanic acid (2 through HRFABMS and NMR data analyses.

Synthesis of 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives

International Nuclear Information System (INIS)

Elhadi, S. A.

2004-09-01

Quinolin derivatives are a group of compounds known to possess a wide range of biological activities. The chemistry of quinolines together with their corresponding aldehydes were dealt with in chapter one of this study. Special emphasis was given to the chemistry of benzaldehyde. Twenty five 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives together with their corresponding intermediates were prepared in this work. Basically, the synthetic design of these compounds arise from the appropriate disconnections of the target 2-phenyl and 2,3-diphenyl-quinolin-4-carboxylic acids. The retro synthesis analysis of these compounds reveals pyruvic acid, aromatic amine and benzaldehyde or phenyl pyruvic acid, aromatic amine and benzaldehyde as possible logical precursors for 2-phenyl-and 2,3-diphenyl- quinoline-4-carboxylic acids respectively. The purity and identities of the synthesized compounds were elucidated through chromatographic and spectroscopic techniques. The compounds were heavily subjected to spectroscopic analysis (UV, IR, GC/MS, 1 H-and 13 C- NMR). The appropriate disconnections and the mechanisms of the corresponding reactions were given and discussed in chapter three. The spectral data were interpreted and correlated with the target structures. The prepared 2-phenyl- and 2,3-diphenyl-quinoline-4-carboxylic acid derivatives were screened for their antibacterial activity. The compounds were tested against the standard bacterial organisms B. subtilis, S. aureus, E. coli and P. vulgaris. Some of these compounds were devoid of antibacterial activity against S. aureus and P. vulgaris, while others showed moderate activity. All of the tested compounds showed an activity against B. subtilis and E. coli. 2,3-diphenyl -6-sulphanilamide-quinolin-4-carboxylic acid showed the highest activity against the four standard tested organisms.(Author)

Synthesis of 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives

Energy Technology Data Exchange (ETDEWEB)

Elhadi, S A [Department of Chemistry, Faculty of Education, University of Khartoum, Khartoum (Sudan)

2004-09-01

Quinolin derivatives are a group of compounds known to possess a wide range of biological activities. The chemistry of quinolines together with their corresponding aldehydes were dealt with in chapter one of this study. Special emphasis was given to the chemistry of benzaldehyde. Twenty five 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives together with their corresponding intermediates were prepared in this work. Basically, the synthetic design of these compounds arise from the appropriate disconnections of the target 2-phenyl and 2,3-diphenyl-quinolin-4-carboxylic acids. The retro synthesis analysis of these compounds reveals pyruvic acid, aromatic amine and benzaldehyde or phenyl pyruvic acid, aromatic amine and benzaldehyde as possible logical precursors for 2-phenyl-and 2,3-diphenyl- quinoline-4-carboxylic acids respectively. The purity and identities of the synthesized compounds were elucidated through chromatographic and spectroscopic techniques. The compounds were heavily subjected to spectroscopic analysis (UV, IR, GC/MS, {sup 1}H-and {sup 13}C- NMR). The appropriate disconnections and the mechanisms of the corresponding reactions were given and discussed in chapter three. The spectral data were interpreted and correlated with the target structures. The prepared 2-phenyl- and 2,3-diphenyl-quinoline-4-carboxylic acid derivatives were screened for their antibacterial activity. The compounds were tested against the standard bacterial organisms B. subtilis, S. aureus, E. coli and P. vulgaris. Some of these compounds were devoid of antibacterial activity against S. aureus and P. vulgaris, while others showed moderate activity. All of the tested compounds showed an activity against B. subtilis and E. coli. 2,3-diphenyl -6-sulphanilamide-quinolin-4-carboxylic acid showed the highest activity against the four standard tested organisms.(Author)

Suitability Assessment of Satellite-Derived Drought Indices for Mongolian Grassland

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Sheng Chang

2017-06-01

Full Text Available In Mongolia, drought is a major natural disaster that can influence and devastate large regions, reduce livestock production, cause economic damage, and accelerate desertification in association with destructive human activities. The objective of this article is to determine the optimal satellite-derived drought indices for accurate and real-time expression of grassland drought in Mongolia. Firstly, an adaptability analysis was performed by comparing nine remote sensing-derived drought indices with reference indicators obtained from field observations using several methods (correlation, consistency percentage (CP, and time-space analysis. The reference information included environmental data, vegetation growth status, and region drought-affected (RDA information at diverse scales (pixel, county, and region for three types of land cover (forest steppe, steppe, and desert steppe. Second, a meteorological index (PED, a normalized biomass (NorBio reference indicator, and the RDA-based drought CP method were adopted for describing Mongolian drought. Our results show that in forest steppe regions the normalized difference water index (NDWI is most sensitive to NorBio (maximum correlation coefficient (MAX_R: up to 0.92 and RDA (maximum CP is 87%, and is most consistent with RDA spatial distribution. The vegetation health index (VHI and temperature condition index (TCI are most correlated with the PED index (MAX_R: 0.75 and soil moisture (MAX_R: 0.58, respectively. In steppe regions, the NDWI is most closely related to soil moisture (MAX_R: 0.69 and the VHI is most related to the PED (MAX_R: 0.76, NorBio (MCC: 0.95, and RDA data (maximum CP is 89%, exhibiting the most consistency with RDA spatial distribution. In desert steppe areas, the vegetation condition index (VCI correlates best with NorBio (MAX_R: 0.92, soil moisture (MAX_R: 0.61, and RDA spatial distribution, while TCI correlates best with the PED (MAX_R: 0.75 and the RDA data (maximum CP is 79

Biotechnological production of caffeic acid derivatives from cell and organ cultures of Echinacea species.

Science.gov (United States)

Murthy, Hosakatte Niranjana; Kim, Yun-Soo; Park, So-Young; Paek, Kee-Yoeup

2014-09-01

Caffeic acid derivatives (CADs) are a group of bioactive compounds which are produced in Echinacea species especially Echinacea purpurea, Echinacea angustifolia, and Echinacea pallida. Echinacea is a popular herbal medicine used in the treatment of common cold and it is also a prominent dietary supplement used throughout the world. Caffeic acid, chlorogenic acid (5-O-caffeoylquinic acid), caftaric acid (2-O-caffeoyltartaric acid), cichoric acid (2, 3-O-dicaffeoyltartaric acid), cynarin, and echinacoside are some of the important CADs which have varied pharmacological activities. The concentrations of these bioactive compounds are species specific and also they vary considerably with the cultivated Echinacea species due to geographical location, stage of development, time of harvest, and growth conditions. Due to these reasons, plant cell and organ cultures have become attractive alternative for the production of biomass and caffeic acid derivatives. Adventitious and hairy roots have been induced in E. pupurea and E. angustifolia, and suspension cultures have been established from flask to bioreactor scale for the production of biomass and CADs. Tremendous progress has been made in this area; various bioprocess methods and strategies have been developed for constant high-quality productivity of biomass and secondary products. This review is aimed to discuss biotechnological methods and approaches employed for the sustainable production of CADs.

Humic acid batteries derived from vermicomposts at different C/N ratios

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Shamsuddin, R. M.; Borhan, A.; Lim, W. K.

2017-06-01

Humic acid is a known fertilizer derived from decomposed organic matters. Organic wastes are normally landfilled for disposal which had contributed negatively to the environment. From waste-to-wealth perspective, such wastes are potential precursors for compost fertilizers. When worms are added into a composting process, the process is termed as vermicomposting. In this work, humic acid from vermicompost derived from campus green wastes was developed into a battery. This adds value proposition to compost instead of being traditionally used solely as soil improver. This research work aimed to study the correlation between electrical potential generated by humic acid at different Carbon to Nitrogen (C/N) ratios of vermicompost at 20, 25, 30 and 35. The temperature and pH profiles of composting revealed that the compost was ready after 55 days. The humic acid was extracted from compost via alkaline extraction followed by precipitation in a strong acid. The extracted humic acid together with other additives were packed into a compartment and termed as vermibattery. Another set of battery running only on the additives was also prepared as a control. The net voltage produced by a single vermibattery cell with Zn and PbO electrodes was in the range of 0.31 to 0.44 V with compost at C/N ratio of 30 gave the highest voltage. The battery can be connected in series to increase the voltage generation. Quality assessment on the compost revealed that the final carbon content is between 16 to 23 wt%, nitrogen content of 0.4 to 0.5 wt%, humic acid yield of 0.7 to 1.5 wt% and final compost mass reduction of 10 to 35 wt%. Composting campus green wastes carries multi-fold benefits of reducing labour requirement, generating fertilizer for campus greenery and green battery construction.

Synthesis of novel {sup 68}Ga-labeled amino acid derivatives for positron emission tomography of cancer cells

Energy Technology Data Exchange (ETDEWEB)

Shetty, Dinesh [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Department of Radiation Applied Life Science, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Jeong, Jae Min, E-mail: jmjng@snu.ac.k [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Department of Radiation Applied Life Science, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Ju, Chang Hwan [Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul (Korea, Republic of); Lee, Yun-Sang [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Department of Radiation Applied Life Science, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Jeong, Seo Young [Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul (Korea, Republic of); Choi, Jae Yeon; Yang, Bo Yeun [Department of Nuclear Medicine, Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of); Department of Radiation Applied Life Science, Seoul National University College of Medicine, Seoul 110-744 (Korea, Republic of)

2010-11-15

Objectives: We developed amino acid derivatives of 1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (DO2A) and 1,4,7,10-tetraazacyclododecane-1,4,7,-triacetic acid (DO3A) that can be labeled with {sup 68}Ga, and we investigated their basic biological properties. Materials and methods: Alanine derivatives of DO2A and DO3A were synthesized by regiospecific nucleophilic attack of DO2tBu and DO3tBu on the {beta}-position of Boc-L-serine-{beta}-lactone, followed by acid hydrolysis. Also, homoalanine derivatives were synthesized by reacting with the protected bromo derivative of homoalanine, which was synthesized from N-Cbz-L-homoserine lactone. Further catalytic reduction and acid cleavage of protected groups resulted in the required products. All derivatives were labeled with {sup 68}Ga. Cell uptake assays were carried out in Hep3B (human hepatoma) and U87MG (human glioma) cell lines at 37{sup o}C. Positron emission tomography (PET) imaging studies were performed using balb/c mice xenografted with CT-26 (mouse colon cancer). Results: All compounds were labeled with >97% efficiency. According to in vitro studies, the labeled amino acid derivatives showed significantly greater uptakes than the control ({sup 68}Ga 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) in cancer cells. Small animal PET images for labeled compounds showed high tumor uptake, as well as kidney and bladder uptakes, at 30 min postinjection. {sup 68}Ga-DO3A-homoalanine showed the highest standardized uptake value ratio (3.9{+-}0.3), followed by {sup 68}Ga-DO2A-alanine (3.1{+-}0.2), {sup 68}Ga-DO3A-alanine (2.8{+-}0.2) and {sup 68}Ga-DO2A-homoalanine (2.3{+-}0.2). Conclusion: These derivatives were found to have high labeling efficiencies, high stabilities, high tumor cell uptakes, high tumor/nontumor xenograft uptakes and low nonspecific uptake in normal organs, except for the kidneys. However, the uptake mechanism of these derivatives remains unclear, and uptake via specific amino acid

Enzymatic Synthesis of Fatty Hydroxamic Acid Derivatives Based on Palm Kernel Oil

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Sidik Silong

2011-08-01

Full Text Available Fatty hydroxamic acid derivatives were synthesized using Lipozyme TL IM catalyst at biphasic medium as the palm kernel oil was dissolved in hexane and hydroxylamine derivatives were dissolved in water: (1 N-methyl fatty hydroxamic acids (MFHAs; (2 N-isopropyl fatty hydroxamic acids (IPFHAs and (3 N-benzyl fatty hydroxamic acids (BFHAs were synthesized by reaction of palm kernel oil and N-methyl hydroxylamine (N-MHA, N-isopropyl hydroxylamine (N-IPHA and N-benzyl hydroxylamine (N-BHA, respectively. Finally, after separation the products were characterized by color testing, elemental analysis, FT-IR and 1H-NMR spectroscopy. For achieving the highest conversion percentage of product the optimum molar ratio of reactants was obtained by changing the ratio of reactants while other reaction parameters were kept constant. For synthesis of MFHAs the optimum mol ratio of N-MHA/palm kernel oil = 6/1 and the highest conversion was 77.8%, for synthesis of IPFHAs the optimum mol ratio of N-IPHA/palm kernel oil = 7/1 and the highest conversion was 65.4% and for synthesis of BFHAs the optimum mol ratio of N-BHA/palm kernel oil = 7/1 and the highest conversion was 61.7%.

Identification and quantitation of new glutamic acid derivatives in soy sauce by UPLC/MS/MS.

Science.gov (United States)

Frerot, Eric; Chen, Ting

2013-10-01

Glutamic acid is an abundant amino acid that lends a characteristic umami taste to foods. In fermented foods, glutamic acid can be found as a free amino acid formed by proteolysis or as a non-proteolytic derivative formed by microorganisms. The aim of the present study was to identify different structures of glutamic acid derivatives in a typical fermented protein-based food product, soy sauce. An acidic fraction was prepared with anion-exchange solid-phase extraction (SPE) and analyzed by UPLC/MS/MS and UPLC/TOF-MS. α-Glutamyl, γ-glutamyl, and pyroglutamyl dipeptides, as well as lactoyl amino acids, were identified in the acidic fraction of soy sauce. They were chemically synthesized for confirmation of their occurrence and quantified in the selected reaction monitoring (SRM) mode. Pyroglutamyl dipeptides accounted for 770 mg/kg of soy sauce, followed by lactoyl amino acids (135 mg/kg) and γ-glutamyl dipeptides (70 mg/kg). In addition, N-succinoylglutamic acid was identified for the first time in food as a minor compound in soy sauce (5 mg/kg). Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.

Chlorophyll-derived fatty acids regulate expression of lipid metabolizing enzymes in liver - a nutritional opportunity

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Wolfrum Christian

2001-01-01

Full Text Available Nutritional values of fatty acid classes are normally discussed on the basis of their saturated, monounsaturated and polyunsaturated structures with implicit understanding that they are straight-chain. Here we focus on chlorophyll-derived phytanic and pristanic acids that are minor isoprenoid branched-chain lipid constituents in food, but of unknown nutritional value. After describing the enzyme machinery that degrades these nutrient fatty acids in the peroxisome, we show by the criteria of a mouse model and of a human cell culture model that they induce with high potency expression of enzymes responsible for beta-oxidation of straight-chain fatty acids in the peroxisome. We summarize present mechanistic knowledge on fatty acid signaling to the nucleus, which involves protein/protein contacts between peroxisome proliferator activated receptor (PPAR and fatty acid binding protein (FABP. In this signaling event the branched-chain fatty acids are the most effective ones. Finally, on the basis of this nutrient-gene interaction we discuss nutritional opportunities and therapeutic aspects of the chlorophyll-derived fatty acids.

Conversion of α-linolenic acid to long-chain omega-3 fatty acid derivatives and alterations of HDL density subfractions and plasma lipids with dietary polyunsaturated fatty acids in Monk parrots (Myiopsitta monachus).

Science.gov (United States)

Petzinger, C; Larner, C; Heatley, J J; Bailey, C A; MacFarlane, R D; Bauer, J E

2014-04-01

The effect of α-linolenic acid from a flaxseed (FLX)-enriched diet on plasma lipid and fatty acid metabolism and possible atherosclerosis risk factors was studied in Monk parrots (Myiopsitta monachus). Twenty-four Monk parrots were randomly assigned to diets containing either 10% ground SUNs or 10% ground FLXs. Feed intake was calculated daily. Blood samples, body condition scores and body weights were obtained at -5 weeks, day 0, 7, 14, 28, 42 and 70. Plasma samples were analysed for total cholesterol, free cholesterol, triacylglycerols and lipoproteins. Phospholipid subfraction fatty acid profiles were determined. By day 70, the FLX group had significantly higher plasma phospholipid fatty acids including 18:3n-3 (α-linolenic acid), 20:5n-3 (eicosapentaenoic acid) and 22:6n-3 (docosahexaenoic acid). The sunflower group had significantly higher plasma phospholipid levels of 20:4n-6 (arachidonic acid). By day 70, the high-density lipoprotein (HDL) peak shifted resulting in significantly different HDL peak densities between the two experimental groups (1.097 g/ml FLX group and 1.095 g/ml SUN group, p = 0.028). The plasma fatty acid results indicate that Monk parrots can readily convert α-linolenic acid to the long-chain omega-3 derivatives including docosahexaenoic acid and reduce 20:4n-6 accumulation in plasma phospholipids. The reason for a shift in the HDL peak density is unknown at this time. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

Optical indicators based on environment sensitive fluorophors

Energy Technology Data Exchange (ETDEWEB)

Shakhsher, Z.M.; Seitz, W.R. (Univ. of New Hampshire, Durham, NC (USA))

1990-01-01

The authors are interested in the development of optical indicators based on environment sensitive fluorophors. The fluorophor is immobilized on a solid substrate. Interaction with analyte modifies the fluorophor environment, leading to a shift in the distribution of emission wavelengths. Because the indicator is based on spectral shift, it is possible to relate analyte concentration to a ratio of intensities at two different wavelengths. This parameter is insensitive to instrumental drift and slow loss of indicator. Two indicator systems have been investigated. Both involve dansyl derivation, i.e., derivatives of 5-dimethylamino-1-naphthalene sulfonic acid.

Natural derivatives of diphenolic acid as substitutes for bisphenol-A

Science.gov (United States)

Ertl, Johanna; Cerri, Elisa; Rizzuto, Matteo; Caretti, Daniele

2014-05-01

Diphenolic acid had been originally used in the first epoxy resins and was later on forgotten as it was substituted by the cheaper bisphenol A. But in the recent years major health concerns have been raised as bisphenol A has a pseudo-hormonal effect on the body, playing the role of estrogen it can cause a severe impact on the organism, especially in males. Moreover it is produced from acetone and phenol, both from fossil, and thus limited resources. On the contrary, diphenolic acid is synthesized from levulinic acid and phenol. Levulinic acid being directly produced by hydrolysis of biomass. By substituting the fossil phenol with natural phenols from lignin or plant extraction we are able to synthesize a fully renewable substitute for bisphenol A. The reactions to yield an epoxy resin have been examined and the reactivity with epichlorohydrin is satisfying. Moreover, some of the derivatives of diphenolic acid have interesting curing properties and preliminary results show excellent properties of the cured resin, including thermal stability and pencil hardness.

In situ synthesis, electrochemical and quantum chemical analysis of an amino acid-derived ionic liquid inhibitor for corrosion protection of mild steel in 1M HCl solution

International Nuclear Information System (INIS)

Kowsari, E.; Arman, S.Y.; Shahini, M.H.; Zandi, H.; Ehsani, A.; Naderi, R.; PourghasemiHanza, A.; Mehdipour, M.

2016-01-01

Highlights: • Electrochemical analysis of effectiveness of an amino acid-derived ionic liquid inhibitor. • Quantum chemical analysis of effectiveness of an amino acid-derived ionic liquid inhibitor. • Finding correlation between electrochemical analysis and quantum chemical analysis. - Abstract: In this study, an amino acid-derived ionic liquid inhibitor, namely tetra-n-butyl ammonium methioninate, was synthesized and the role this inhibitor for corrosion protection of mild steel exposed to 1.0 M HCl was investigated using electrochemical, quantum and surface analysis. By taking advantage of potentiodynamic polarization, the inhibitory action of tetra-n-butyl ammonium methioninate was found to be mainly mixed-type with dominant anodic inhibition. The effectiveness of the inhibitor was also indicated using electrochemical impedance spectroscopy (EIS). Moreover, to provide further insight into the mechanism of inhibition, electrochemical noise (EN) and quantum chemical calculations of the inhibitor were performed.

A digital image-based method for determining of total acidity in red wines using acid-base titration without indicator.

Science.gov (United States)

Tôrres, Adamastor Rodrigues; Lyra, Wellington da Silva; de Andrade, Stéfani Iury Evangelista; Andrade, Renato Allan Navarro; da Silva, Edvan Cirino; Araújo, Mário César Ugulino; Gaião, Edvaldo da Nóbrega

2011-05-15

This work proposes the use of digital image-based method for determination of total acidity in red wines by means of acid-base titration without using an external indicator or any pre-treatment of the sample. Digital images present the colour of the emergent radiation which is complementary to the radiation absorbed by anthocyanines present in wines. Anthocyanines change colour depending on the pH of the medium, and from the variation of colour in the images obtained during titration, the end point can be localized with accuracy and precision. RGB-based values were employed to build titration curves, and end points were localized by second derivative curves. The official method recommends potentiometric titration with a NaOH standard solution, and sample dilution until the pH reaches 8.2-8.4. In order to illustrate the feasibility of the proposed method, titrations of ten red wines were carried out. Results were compared with the reference method, and no statistically significant difference was observed between the results by applying the paired t-test at the 95% confidence level. The proposed method yielded more precise results than the official method. This is due to the trivariate nature of the measurements (RGB), associated with digital images. Copyright © 2011 Elsevier B.V. All rights reserved.

Performance, kinetics, and equilibrium of methylene blue adsorption on biochar derived from eucalyptus saw dust modified with citric, tartaric, and acetic acids.

Science.gov (United States)

Sun, Lei; Chen, Dongmei; Wan, Shungang; Yu, Zebin

2015-12-01

Biochar derived from eucalyptus saw dust modified with citric, tartaric, and acetic acids at low temperatures was utilized as adsorbent to remove methylene blue (MB) from aqueous solutions. Fourier transform infrared spectroscopy analysis showed that the carboxyl group was introduced on the biochar surface. Adsorption experiment data indicated that eucalyptus saw dust modified with citric acid showed higher MB adsorption efficiency than that modified with tartaric and acetic acids. Pseudo-second-order kinetics was the most suitable model for describing MB adsorption on biochar compared with pseudo-first-order, Elovich, and intraparticle diffusion models. The calculated values of ΔG(0) and ΔH(0) indicated the spontaneous and endothermic nature of the adsorption process. MB adsorption on biochar followed the Langmuir isotherm. The maximum adsorption capacities for eucalyptus saw dust modified with citric, tartaric, and acetic acids were 178.57, 99.01, and 29.94 mg g(-1), respectively, at 35°C. Copyright © 2015 Elsevier Ltd. All rights reserved.

Tracking of Drug Release and Material Fate for Naturally Derived Omega-3 Fatty Acid Biomaterials.

Science.gov (United States)

Faucher, Keith M; Artzi, Natalie; Beck, Moshe; Beckerman, Rita; Moodie, Geoff; Albergo, Theresa; Conroy, Suzanne; Dale, Alicia; Corbeil, Scott; Martakos, Paul; Edelman, Elazer R

2016-03-01

In vitro and in vivo studies were conducted on omega-3 fatty acid-derived biomaterials to determine their utility as an implantable material for adhesion prevention following soft tissue hernia repair and as a means to allow for the local delivery of antimicrobial or antibiofilm agents. Naturally derived biomaterials offer several advantages over synthetic materials in the field of medical device development. These advantages include enhanced biocompatibility, elimination of risks posed by the presence of toxic catalysts and chemical crosslinking agents, and derivation from renewable resources. Omega-3 fatty acids are readily available from fish and plant sources and can be used to create implantable biomaterials either as a stand-alone device or as a device coating that can be utilized in local drug delivery applications. In-depth characterization of material erosion degradation over time using non-destructive imaging and chemical characterization techniques provided mechanistic insight into material structure: function relationship. This in turn guided rational tailoring of the material based on varying fatty acid composition to control material residence time and hence drug release. These studies demonstrate the utility of omega-3 fatty acid derived biomaterials as an absorbable material for soft tissue hernia repair and drug delivery applications.

Evaluation of preservative effectiveness of gallic acid derivatives in aluminum hydroxide gel-USP

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Anurag Khatkar

2013-01-01

Full Text Available Background: Preservatives are added to most of the pharmaceutical preparations to prevent them from deterioration throughout their shelf life. Literature reveals that the common synthetic preservatives have many limitations, such as development of microbial resistance (in due course of time and several serious side-effects. Aim: The aim of this study is to find out new preservatives synthesized from natural sources, which may have better efficiency than the existing synthetic preservatives. The derivatives of naturally occurring gallic acid were subjected for their preservative efficacy study. Their preservative efficiency was evaluated and compared with the standard parabens. Materials and Methods: The selected amide, anilide and ester derivatives of gallic acid were subjected to preservative efficacy testing in an official antacid preparation, {aluminum hydroxide gel-USP (United States Pharmacopoeia} against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans, and Aspergillus niger as representative challenging microorganisms as per USP 2004 guidelines. Results: The selected derivatives were found to be effective against all selected strains and showed preservative efficacy comparable to that of standard and even better in case E. coli, C. albicans and A. niger. The 8-hydroxy quinoline ester derivative showed better preservative efficacy than standard as well as other derivatives. Conclusion: The newly synthesized gallic acid preservatives were found to be effective in the proposed pharmaceutical preparation (Aluminium Hydroxide Gel - USP. Also, the synthesized preservatives have shown comparative and even better efficacy than the existing parabens and hence they have potential for use in pharmaceutical preparations.

Semi-Preparative Separation of 10 Caffeoylquinic Acid Derivatives Using High Speed Counter-Current Chromatogaphy Combined with Semi-Preparative HPLC from the Roots of Burdock (Arctium lappa L.).

Science.gov (United States)

Zheng, Zhenjia; Wang, Xiao; Liu, Pengli; Li, Meng; Dong, Hongjing; Qiao, Xuguang

2018-02-15

Burdock roots are healthy dietary supplements and a kind of famous traditional Chinese medicine, which contains large amounts of caffeoylquinic acid derivatives. However, little research has been reported on the preparative separation of these compounds from burdock roots. In the present study, a combinative method of HSCCC and semi-preparative HPLC was developed for the semi-preparative separation of caffeoylquinic acid derivatives from the burdock roots. The ethyl acetate extract of burdock roots was first fractionated by MCI macroporous resin chromatography and give three fractions (Fr. 1-3) from the elution of 40% methanol. Then, these three fractions (120 mg) were separately subjected to HSCCC for purification with the solvent system composed of petroleum ether-ethyl acetate-methanol-water at different volume ratios, and the mixtures were further purified by semi-preparative HPLC. As a result, a total of eight known caffeoylquinic acid derivatives including 3- O -caffeoylquinic acid (32.7 mg, 95.7%), 1,5- O - dicaffeoylquinic acid (4.3 mg, 97.2%), 3- O -caffeoylquinic acid methyl ester (12.1 mg, 93.2%), 1,3- O -dicaffeoylquinic acid (42.9 mg, 91.1%), 1,5- O -dicaffeoyl-3- O -(4-maloyl)-quinic acid (4.3 mg, 84.5%), 4,5- O -dicaffeoylquinic acid (5.3 mg, 95.5%), 1,5- O -dicaffeoyl-3- O -succinylquinic acid (8.7 mg, 93.4%), and 1,5- O -dicaffeoyl-4- O -succinylquinic acid (1.7 mg, 91.8%), and two new compounds were obtained. The new compounds were 1,4- O -dicaffeoyl-3-succinyl methyl ester quinic acid (14.6 mg, 96.1%) and 1,5- O -dicaffeoyl-3- O -succinyl methyl ester quinic acid (3.1 mg, 92.6%), respectively. The research indicated that the combination of HSCCC and semi-preparative HPLC is a highly efficient approach for preparative separation of the instability and bioactive caffeoylquinic acid derivatives from natural products.

M-Polynomials and Topological Indices of Dominating David Derived Networks

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Kang Shin Min

2018-03-01

Full Text Available There is a strong relationship between the chemical characteristics of chemical compounds and their molecular structures. Topological indices are numerical values associated with the chemical molecular graphs that help to understand the physical features, chemical reactivity, and biological activity of chemical compound. Thus, the study of the topological indices is important. M-polynomial helps to recover many degree-based topological indices for example Zagreb indices, Randic index, symmetric division idex, inverse sum index etc. In this article we compute M-polynomials of dominating David derived networks of the first type, second type and third type of dimension n and find some topological properties by using these M-polynomials. The results are plotted using Maple to see the dependence of topological indices on the involved parameters.

CEC enantioseparations of carboxylic acids on silica-based monoliths modified with ergot alkaloid derivative

Czech Academy of Sciences Publication Activity Database

Messina, A.; Moroni, S.; Flieger, Miroslav; Sinibaldi, M.; Ursini, O.

2009-01-01

Roč. 30, č. 16 (2009), s. 2890-2896 ISSN 0173-0835 Institutional research plan: CEZ:AV0Z50200510 Keywords : 2-Aryloxypropionic acids * chiral separations * dansyl amino acid derivatives Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.077, year: 2009

Hydroxycinnamic Acids and Their Derivatives: Cosmeceutical Significance, Challenges and Future Perspectives, a Review

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Oludemi Taofiq

2017-02-01

Full Text Available Bioactive compounds from natural sources, due to their widely-recognized benefits, have been exploited as cosmeceutical ingredients. Among them, phenolic acids emerge with a very interesting potential. In this context, this review analyzes hydroxycinnamic acids and their derivatives as multifunctional ingredients for topical application, as well as the limitations associated with their use in cosmetic formulations. Hydroxycinnamic acids and their derivatives display antioxidant, anti-collagenase, anti-inflammatory, antimicrobial and anti-tyrosinase activities, as well as ultraviolet (UV protective effects, suggesting that they can be exploited as anti-aging and anti-inflammatory agents, preservatives and hyperpigmentation-correcting ingredients. Due to their poor stability, easy degradation and oxidation, microencapsulation techniques have been employed for topical application, preventing them from degradation and enabling a sustained release. Based on the above findings, hydroxycinnamic acids present high cosmetic potential, but studies addressing the validation of their benefits in cosmetic formulations are still scarce. Furthermore, studies dealing with skin permeation are scarcely available and need to be conducted in order to predict the topical bioavailability of these compounds after application.

Brevianamides and Mycophenolic Acid Derivatives from the Deep-Sea-Derived Fungus Penicillium brevicompactum DFFSCS025

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Xinya Xu

2017-02-01

Full Text Available Four new compounds (1–4, including two brevianamides and two mycochromenic acid derivatives along with six known compounds were isolated from the deep-sea-derived fungus Penicillium brevicompactum DFFSCS025. Their structures were elucidated by spectroscopic analysis. Moreover, the absolute configurations of 1 and 2 were determined by quantum chemical calculations of the electronic circular dichroism (ECD spectra. Compound 9 showed moderate cytotoxicity against human colon cancer HCT116 cell line with IC50 value of 15.6 μM. In addition, 3 and 5 had significant antifouling activity against Bugula neritina larval settlement with EC50 values of 13.7 and 22.6 μM, respectively. The NMR data of 6, 8, and 9 were assigned for the first time.

Efficacious Intestinal Permeation Enhancement Induced by the Sodium Salt of 10-undecylenic Acid, A Medium Chain Fatty Acid Derivative

OpenAIRE

Brayden, David J.; Walsh, Edwin

2014-01-01

10-undecylenic acid (UA) is an OTC antifungal therapy and a nutritional supplement. It is an unsaturated medium chain fatty acid (MCFA) derivative, so our hypothesis was that its 11-mer sodium salt, uC11, would improve intestinal permeation similar to the established enhancer, sodium caprate (C10), but without the toxicity of the parent saturated MCFA, decylenic acid (C11). MTT assay and high-content screening (HCS) confirmed a cytotoxicity ranking in Caco-2 cells: C11 > C10 = uC11. Five to t...

Preparation and adsorption behavior for metal ions and humic acid of chitosan derivatives crosslinked by irradiation

International Nuclear Information System (INIS)

Zhao Long; Mitomo, H.; Yoshii, F.

2006-01-01

Introduction: Removing metal ions and humic acid from water in water treatment has attracted much environment and health interests. Adsorbents, derived from a nature polymer, are desired in the viewpoints of environment-conscious technologies. Recently, some nature materials such as chitin, chitosan and their derivatives have been identified as an attractive option due to their distinctive properties. For an insoluble adsorbent based on these polymers to be obtained over a broad pH range, modification through crosslinking is required. Crosslinking agents such as glutaric dialdehyde and ethylene glycol diglycidyl ether are frequently used for modification. However, these crosslinking agents are not preferred because of their physiological toxicity. Radiation-crosslinking without any additive in the fabrication process results in a high-purity product. In a previous work, we applied ionizing radiation to induce the crosslinking of carboxymethylchitosan under highly concentrated paste-like conditions. The aim of this study is to investigate the adsorption behavior of metal ions, humic acid on irradiation-crosslinked carboxymethylchitosan. Experimental: Irradiation of chitosan samples at paste-like state was done with an electron beam. The solubility test of these crosslinked materials were investigated in acidic, alkaline media, and some organic solvents. Swelling and charged characteristic analyses demonstrated typically pH-sensitive properties of these crosslinked materials. Scanning electron microscopic images showed that the crosslinked samples possessed porous morphological structure. The adsorption studies were carried out by the batch method at room temperature. Adsorption of heavy metal ions (such as Cu 2+ , Cd 2+ ) and humic acid onto crosslinked samples was found to be strongly pH-dependent. Adsorption kinetic studies indicated the rapid removal of metal ions, and humic acid from the aqueous solutions. Also, isothermal adsorption data revealed that Cu 2

Synthesis and Anticancer Activities of Glycyrrhetinic Acid Derivatives

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Yang Li

2016-02-01

Full Text Available A total of forty novel glycyrrhetinic acid (GA derivatives were designed and synthesized. The cytotoxic activity of the novel compounds was tested against two human breast cancer cell lines (MCF-7, MDA-MB-231 in vitro by the MTT method. The evaluation results revealed that, in comparison with GA, compound 42 shows the most promising anticancer activity (IC50 1.88 ± 0.20 and 1.37 ± 0.18 µM for MCF-7 and MDA-MB-231, respectively and merits further exploration as a new anticancer agent.

Diverse Bacterial PKS Sequences Derived From Okadaic Acid-Producing Dinoflagellates

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Kathleen S. Rein

2008-05-01

Full Text Available Okadaic acid (OA and the related dinophysistoxins are isolated from dinoflagellates of the genus Prorocentrum and Dinophysis. Bacteria of the Roseobacter group have been associated with okadaic acid producing dinoflagellates and have been previously implicated in OA production. Analysis of 16S rRNA libraries reveals that Roseobacter are the most abundant bacteria associated with OA producing dinoflagellates of the genus Prorocentrum and are not found in association with non-toxic dinoflagellates. While some polyketide synthase (PKS genes form a highly supported Prorocentrum clade, most appear to be bacterial, but unrelated to Roseobacter or Alpha-Proteobacterial PKSs or those derived from other Alveolates Karenia brevis or Crytosporidium parvum.

Solubility of sparingly soluble drug derivatives of anthranilic acid.

Science.gov (United States)

Domańska, Urszula; Pobudkowska, Aneta; Pelczarska, Aleksandra

2011-03-24

This work is a continuation of our systematic study of the solubility of pharmaceuticals (Pharms). All substances here are derivatives of anthranilic acid, and have an anti-inflammatory direction of action (niflumic acid, flufenamic acid, and diclofenac sodium). The basic thermal properties of pure Pharms, i.e., melting and glass-transition temperatures as well as the enthalpy of melting, have been measured with the differential scanning microcalorimetry technique (DSC). Molar volumes have been calculated with the Barton group contribution method. The equilibrium mole fraction solubilities of three pharmaceuticals were measured in a range of temperatures from 285 to 355 K in three important solvents for Pharm investigations: water, ethanol, and 1-octanol using a dynamic method and spectroscopic UV-vis method. The experimental solubility data have been correlated by means of the commonly known G(E) equation: the NRTL, with the assumption that the systems studied here have revealed simple eutectic mixtures. pK(a) precise measurement values have been investigated with the Bates-Schwarzenbach spectrophotometric method. © 2011 American Chemical Society

Synthesis of new, UV-photoactive dansyl derivatives for flow cytometric studies on bile acid uptake.

Science.gov (United States)

Rohacova, Jana; Marin, M Luisa; Martínez-Romero, Alicia; O'Connor, José-Enrique; Gomez-Lechon, M Jose; Donato, M Teresa; Castell, Jose V; Miranda, Miguel A

2009-12-07

Four new fluorescent derivatives of cholic acid have been synthesized; they incorporate a dansyl moiety at 3alpha-, 3beta-, 7alpha- or 7beta- positions. These cholic acid analogs are UV photoactive and also exhibit green fluorescence. In addition, they have been demonstrated to be suitable for studying the kinetics of bile acid transport by flow cytometry.

One-pot conversion of biomass-derived xylose and furfural into levulinate esters via acid catalysis.

Science.gov (United States)

Hu, Xun; Jiang, Shengjuan; Wu, Liping; Wang, Shuai; Li, Chun-Zhu

2017-03-07

Direct conversion of biomass-derived xylose and furfural into levulinic acid, a platform molecule, via acid-catalysis has been accomplished for the first time in dimethoxymethane/methanol. Dimethoxymethane acted as an electrophile to transform furfural into 5-hydroxymethylfurfural (HMF). Methanol suppressed both the polymerisation of the sugars/furans and the Aldol condensation of levulinic acid/ester.

Cyclopropane fatty acid synthase mutants of probiotic human-derived Lactobacillus reuteri are defective in TNF inhibition.

Science.gov (United States)

Jones, Sara E; Whitehead, Kristi; Saulnier, Delphine; Thomas, Carissa M; Versalovic, James; Britton, Robert A

2011-01-01

Although commensal microbes have been shown to modulate host immune responses, many of the bacterial factors that mediate immune regulation remain unidentified. Select strains of human-derived Lactobacillus reuteri synthesize immunomodulins that potently inhibit production of the inflammatory cytokine TNF. In this study, genetic and genomic approaches were used to identify and investigate L. reuteri genes required or human TNF immunomodulatory activity. Analysis of membrane fatty acids from multiple L. reuteri strains cultured in MRS medium showed that only TNF inhibitory strains produced the cyclopropane fatty acid (CFA) lactobacillic acid. The enzyme cyclopropane fatty acid synthase is required for synthesis of CFAs such as lactobacillic acid, therefore the cfa gene was inactivated and supernatants from the cfa mutant strain were assayed for TNF inhibitory activity. We found that supernatants from the wild-type strain, but not the cfa mutant, suppressed TNF production by activated THP-1 human monocytoid cells Although this suggested a direct role for lactobacillic acid in immunomodulation, purified lactobacillic acid did not suppress TNF at physiologically relevant concentrations. We further analyzed TNF inhibitory and TNF non-inhibitory strains under different growth conditions and found that lactobacillic acid production did not correlate with TNF inhibition. These results indicate that cfa indirectly contributed to L. reuter immunomodulatory activity and suggest that other mechanisms, such as decreased membrane fluidity or altered expression of immunomodulins, result in the loss of TNF inhibitory activity. By increasing our understanding of immunomodulation by probiotic species, beneficial microbes can be rationally selected to alleviate intestinal inflammation.

One-Pot Synthesis of Novel Chiral β-Amino Acid Derivatives by Enantioselective Mannich Reactions Catalyzed by Squaramide Cinchona Alkaloids

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Kankan Zhang

2013-05-01

Full Text Available An efficient one-pot synthesis of novel β-amino acid derivatives containing a thiadiazole moiety was developed using a chiral squaramide cinchona alkaloid as organocatalyst. The reactions afforded chiral β-amino acid derivatives in moderate yields and with moderate to excellent enantioselectivities. The present study demonstrated for the first time the use of a Mannich reaction catalyzed by a chiral bifunctional organocatalyst for the one-pot synthesis of novel β-amino acid derivatives bearing a 1,3,4-thiadiazole moiety on nitrogen.

Enhanced lignin monomer production caused by cinnamic Acid and its hydroxylated derivatives inhibits soybean root growth.

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Rogério Barbosa Lima

Full Text Available Cinnamic acid and its hydroxylated derivatives (p-coumaric, caffeic, ferulic and sinapic acids are known allelochemicals that affect the seed germination and root growth of many plant species. Recent studies have indicated that the reduction of root growth by these allelochemicals is associated with premature cell wall lignification. We hypothesized that an influx of these compounds into the phenylpropanoid pathway increases the lignin monomer content and reduces the root growth. To confirm this hypothesis, we evaluated the effects of cinnamic, p-coumaric, caffeic, ferulic and sinapic acids on soybean root growth, lignin and the composition of p-hydroxyphenyl (H, guaiacyl (G and syringyl (S monomers. To this end, three-day-old seedlings were cultivated in nutrient solution with or without allelochemical (or selective enzymatic inhibitors of the phenylpropanoid pathway in a growth chamber for 24 h. In general, the results showed that 1 cinnamic, p-coumaric, caffeic and ferulic acids reduced root growth and increased lignin content; 2 cinnamic and p-coumaric acids increased p-hydroxyphenyl (H monomer content, whereas p-coumaric, caffeic and ferulic acids increased guaiacyl (G content, and sinapic acid increased sinapyl (S content; 3 when applied in conjunction with piperonylic acid (PIP, an inhibitor of the cinnamate 4-hydroxylase, C4H, cinnamic acid reduced H, G and S contents; and 4 when applied in conjunction with 3,4-(methylenedioxycinnamic acid (MDCA, an inhibitor of the 4-coumarate:CoA ligase, 4CL, p-coumaric acid reduced H, G and S contents, whereas caffeic, ferulic and sinapic acids reduced G and S contents. These results confirm our hypothesis that exogenously applied allelochemicals are channeled into the phenylpropanoid pathway causing excessive production of lignin and its main monomers. By consequence, an enhanced stiffening of the cell wall restricts soybean root growth.

Effects of drying on caffeoylquinic acid derivative content and antioxidant capacity of sweet potato leaves

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Toong Long Jeng

2015-12-01

Full Text Available Caffeoylquinic acid (CQA derivatives are known to possess antioxidative potential and have many beneficial effects on human health. The present study compared the CQA contents and antioxidant activities of aerial parts of sweet potato plants. The effects of drying methods (freeze drying, and drying at 30°C, 70°C, and 100°C on these two parameters of the first fully expanded leaves were also assessed. The results indicated that the CQA derivatives were detectable in leaves, stem, and flowers of sweet potato plants (varied from 39.34 mg/g dry weight to 154.05 mg/g dry weight, with the leaves (particularly expanding and first fully expanded leaves containing more CQA derivatives than other aerial plant parts. The expanding and first fully expanded leaves also exhibited greater antioxidant activities than other aerial plant parts, possibly due to their higher contents of CQA derivatives. Drying method significantly affected the content of CQA derivatives in dried sweet potato leaf tissues. Drying treatments at both 70°C and 100°C significantly reduced the CQA derivative content and antioxidant activity in the first fully expanded leaves. Among the tested drying methods, the freeze-drying method demonstrated the preservation of the highest amount of CQA derivatives (147.84 mg/g and antioxidant property. However, 30°C cool air drying was also a desirable choice (total CQA derivative content was reduced to only 129.52 mg/g, compared to 70°C and 100°C hot air drying, for commercial-scale processing of sweet potato leaves, if the higher operation cost of freeze drying was a major concern.

Discovery of a novel activator of 5-lipoxygenase from an anacardic acid derived compound collection

NARCIS (Netherlands)

Wisastra, Rosalina; Kok, Petra A. M.; Eleftheriadis, Nikolaos; Baumgartner, Matthew P.; Camacho, Carlos J.; Haisma, Hidde J.; Dekker, Frank J.

2013-01-01

Lipoxygenases (LOXs) and cyclooxygenases (COXs) metabolize poly-unsaturated fatty acids into inflammatory signaling molecules. Modulation of the activity of these enzymes may provide new approaches for therapy of inflammatory diseases. In this study, we screened novel anacardic acid derivatives as

Comparative photocatalytic study of two selected pesticide derivatives, indole-3-acetic acid and indole-3-butyric acid in aqueous suspensions of titanium dioxide

Energy Technology Data Exchange (ETDEWEB)

Qamar, M. [Department of Chemistry, Aligarh Muslim University, Aligarh 202002 (India); Muneer, M. [Department of Chemistry, Aligarh Muslim University, Aligarh 202002 (India)]. E-mail: cht12mm@amu.ac.in

2005-04-11

Heterogeneous photocatalysed degradation of two selected pesticide derivatives such as indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) has been investigated in aqueous suspensions of titanium dioxide by monitoring the change in substrate concentration employing UV spectroscopic analysis technique and depletion in total organic carbon (TOC) content as a function of irradiation time. The degradation kinetics was studied under different conditions such as pH, types of TiO{sub 2,} substrate and catalyst concentration, and in the presence of electron acceptor such as hydrogen peroxide (H{sub 2}O{sub 2}) besides molecular oxygen. The degradation rates were found to be strongly influenced by all the above parameters. The photocatalyst Degussa P25 showed comparatively highest photocatalytics. The pesticide derivative, indole-3-acetic acid was found to degrade slightly faster than indole-3-butyric acid.

Synthesis and Anchoring of Antineoplastic Ferrocene and Phthalocyanine Derivatives on Water-Soluble Polymeric Drug Carriers Derived from Lysine and Aspartic Acid

OpenAIRE

Maree, M. David; Neuse, Eberhard W.; Erasmus, Elizabeth; Swarts, Jannie C.

2007-01-01

The general synthetic strategy towards water-soluble biodegradable drug carriers and the properties that they must have are discussed. The syntheses of water-soluble biodegradable copolymers of lysine and aspartic acid as potential drug-delivering devices, having amine-functionalised side chains are then described. Covalent anchoring of carboxylic acid derivatives of the antineoplastic ferrocene and photodynamically active phthalocyanine moieties to the amine-containing drug carrier copolymer...

Semi-Empirical Predictions on the Structure and Properties of ent-Kaurenoic Acid and Derivatives

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Jose Isagani B. Janairo

2011-01-01

Full Text Available The physicochemical properties of ent- kaurenoic acid model derivatives, which possibly influence its therapeutic application, were calculated. Results revealed that the molecule possess favourable attributes which renders it possible to be considered as a drug lead only that its very hydrophobic nature can result to poor bioavailabilty, low absorption and poor systemic circulation. In silico simulations revealed that this setback can be overcome by introduction of hydroxyl group to the tertiary carbon of ent-kaurenoic acid employing m-CPBA catalyzed hydroxylation, thus, unleashing its full drug potency. Moreover, molecular similarity analyses derived from semi-empirical calculations between ent-kaurenoic acid and a set of kaurane diterpenoids showed differences in hydrophobic complementarity, size and electronic properties despite possessing nearly identical molecular frameworks, thus, arriving in a generalization for their observed mechanistic differences on acting on different targets.

Enhancing the Bioconversion of Azelaic Acid to Its Derivatives by Response Surface Methodology

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Nurshafira Khairudin

2018-02-01

Full Text Available Azelaic acid (AzA and its derivatives have been known to be effective in the treatment of acne and various cutaneous hyperpigmentary disorders. The esterification of azelaic acid with lauryl alcohol (LA to produce dilaurylazelate using immobilized lipase B from Candida antarctica (Novozym 435 is reported. Response surface methodology was selected to optimize the reaction conditions. A well-fitting quadratic polynomial regression model for the acid conversion was established with regards to several parameters, including reaction time and temperature, enzyme amount, and substrate molar ratios. The regression equation obtained by the central composite design of RSM predicted that the optimal reaction conditions included a reaction time of 360 min, 0.14 g of enzyme, a reaction temperature of 46 °C, and a molar ratio of substrates of 1:4.1. The results from the model were in good agreement with the experimental data and were within the experimental range (R2 of 0.9732.The inhibition zone can be seen at dilaurylazelate ester with diameter 9.0±0.1 mm activities against Staphylococcus epidermidis S273. The normal fibroblasts cell line (3T3 was used to assess the cytotoxicity activity of AzA and AzA derivative, which is dilaurylazelate ester. The comparison of the IC50 (50% inhibition of cell viability value for AzA and AzA derivative was demonstrated. The IC50 value for AzA was 85.28 μg/mL, whereas the IC50 value for AzA derivative was more than 100 μg/mL. The 3T3 cell was still able to survive without any sign of toxicity from the AzA derivative; thus, it was proven to be non-toxic in this MTT assay when compared with AzA.

Synthesis and Antibacterial Evaluation of New N-acylhydrazone Derivatives from Dehydroabietic Acid

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Chenhai Gu

2012-04-01

Full Text Available A series of new N-acylhydrazone derivatives were synthesized in good yields through the reactions of dehydroabietic acid hydrazide with a variety of substituted arylaldehydes. The structures of the synthesized compounds were confirmed by IR, 1H- and 13C-NMR, ESI-MS, elemental analysis and single crystal X-ray diffraction. From the crystal structure of compound 4l, the C=N double bonds of these N-acylhydrazones showed (E-configuration, while the NMR data of compounds 4a–q indicated the existence of two rotamers for each compound in solution. The target compounds were evaluated for their antibacterial activities against four microbial strains. The result suggested that several compounds exhibited pronounced antibacterial activities. Particularly, compound 4p exhibited good antibacterial activity against Staphylococcus aureus and Bacillus subtilis comparable to positive control. The possible antibacterial metabolism and the strategy for further optimization of this compound were also discussed.

Semi-Preparative Separation of 10 Caffeoylquinic Acid Derivatives Using High Speed Counter-Current Chromatogaphy Combined with Semi-Preparative HPLC from the Roots of Burdock (Arctium lappa L.

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Zhenjia Zheng

2018-02-01

Full Text Available Burdock roots are healthy dietary supplements and a kind of famous traditional Chinese medicine, which contains large amounts of caffeoylquinic acid derivatives. However, little research has been reported on the preparative separation of these compounds from burdock roots. In the present study, a combinative method of HSCCC and semi-preparative HPLC was developed for the semi-preparative separation of caffeoylquinic acid derivatives from the burdock roots. The ethyl acetate extract of burdock roots was first fractionated by MCI macroporous resin chromatography and give three fractions (Fr. 1–3 from the elution of 40% methanol. Then, these three fractions (120 mg were separately subjected to HSCCC for purification with the solvent system composed of petroleum ether-ethyl acetate-methanol-water at different volume ratios, and the mixtures were further purified by semi-preparative HPLC. As a result, a total of eight known caffeoylquinic acid derivatives including 3-O-caffeoylquinic acid (32.7 mg, 95.7%, 1,5-O- dicaffeoylquinic acid (4.3 mg, 97.2%, 3-O-caffeoylquinic acid methyl ester (12.1 mg, 93.2%, 1,3-O-dicaffeoylquinic acid (42.9 mg, 91.1%, 1,5-O-dicaffeoyl-3-O-(4-maloyl-quinic acid (4.3 mg, 84.5%, 4,5-O-dicaffeoylquinic acid (5.3 mg, 95.5%, 1,5-O-dicaffeoyl-3-O-succinylquinic acid (8.7 mg, 93.4%, and 1,5-O-dicaffeoyl-4-O-succinylquinic acid (1.7 mg, 91.8%, and two new compounds were obtained. The new compounds were 1,4-O-dicaffeoyl-3-succinyl methyl ester quinic acid (14.6 mg, 96.1% and 1,5-O-dicaffeoyl-3-O-succinyl methyl ester quinic acid (3.1 mg, 92.6%, respectively. The research indicated that the combination of HSCCC and semi-preparative HPLC is a highly efficient approach for preparative separation of the instability and bioactive caffeoylquinic acid derivatives from natural products.

Application of l-ascorbic acid and its derivatives (sodium ascorbyl phosphate and magnesium ascorbyl phosphate) in topical cosmetic formulations: stability studies

International Nuclear Information System (INIS)

Smaoui, S.; Hilima, H.B.

2013-01-01

The present study aimed to formulate and subsequently evaluate a topical skin-care cream (o/w emulsion) from l-ascorbic acid and its derivatives (sodium ascorbyl phosphate and magnesium ascorbyl phosphate) at 2% versus its vehicle (Control). Formulations were developed by entrapping it in the oily phase of o/w emulsion and were stored at 8 degree C, 25 degree C and 40 degree C (in incubator) for a period of four weeks to investigate their stability. In the physical analysis, the evaluation parameters consisted of color, smell, phase separation, centrifugation, and liquefaction. Chemical stability of both derivatives was established by HPLC analysis. In the chemical analysis, the formulation with sodium ascorbyl phosphate was more stable than those with magnesium ascorbyl phosphate and l-ascorbic acid. The microbiological stability of the formulations was also evaluated. The findings indicated that the formulations with l-ascorbic acid and its derivatives were efficient against the proliferation of various spoilage microorganisms, including aerobic plate counts as well as Pseudomonas aeruginosa, Staphylococcus aureus, and yeast and mold counts. The results presented in this work showed good stability throughout the experimental period. Newly formulated emulsion proved to exhibit a number of promising properties and attributes that might open new opportunities for the construction of more efficient, safe, and cost-effective skin-care, cosmetic, and pharmaceutical products. (author)

Aggregation behavior of cholic acid derivatives in organic solvents and in water

NARCIS (Netherlands)

Willemen, H.M.

2002-01-01

In this thesis various cholic acid derivatives are reported that display aggregation in water or in organic solvents. Spontaneous aggregation of single molecules into larger, ordered structures occurs at the borderline of solubility. Amphiphilic compounds, or surfactants, which possess a

Selective displacement of the tributylstannyl group to form [125I]phenylboronic acid derivatives

International Nuclear Information System (INIS)

Kinsey, B.M.; Kassis, A.I.

1990-01-01

Three radioiodinated phenylboronic acid derivatives (1a, 2a, 3a) were prepared at the no-carrier-added level by selective displacement of the corresponding tributylstannyl group. The tributylstannyl compounds 1b, 2b, and 3b were synthesized from the bromo derivatives 1c, 2c and 3c. Radioiodination was accomplished using Na 125 I and either Chloramine-T or peracetic acid to give 1a, 2a and 3a in radiochemical yields of 46, 26, and 67% respectively after HPLC purification. Compounds 1a, 2a and 3a were concentrated in vitro preferentially in HT-29 human colon carcinoma cells compared to V79 Chinese hamster lung fibroblasts, with 3a having the highest uptake

2-Thiophenecarboxylic acid hydrazide Derivatives: Synthesis and Anti-Tuberculosis Studies

Science.gov (United States)

Fahmi, M. R. G.; Khumaidah, L.; Ilmiah, T. K.; Fadlan, A.; Santoso, M.

2018-04-01

One of the most frequent and widespread infectious diseases especially in developing countries is tuberculosis (TB). The number of TB drug resistant tend to increase, and there has been no new TB drug introduce since the 1960s. Six 2-Thiophenecarboxylic acid hydrazide derivatives were synthesized in 90-97% yields, and 2-thiophenecarbonylhydrazone-5, 7-dibromoisatin showed the highest activity in inhibiting M. tuberculosis H37Rv.

Potentiometric Measurement of Transition Ranges and Titration Errors for Acid/Base Indicators

Science.gov (United States)

Flowers, Paul A.

1997-07-01

Sophomore analytical chemistry courses typically devote a substantial amount of lecture time to acid/base equilibrium theory, and usually include at least one laboratory project employing potentiometric titrations. In an effort to provide students a laboratory experience that more directly supports their classroom discussions on this important topic, an experiment involving potentiometric measurement of transition ranges and titration errors for common acid/base indicators has been developed. The pH and visually-assessed color of a millimolar strong acid/base system are monitored as a function of added titrant volume, and the resultant data plotted to permit determination of the indicator's transition range and associated titration error. Student response is typically quite positive, and the measured quantities correlate reasonably well to literature values.

Effect of intravenous administration of D-lysergic acid diethylamide on initiation of protein synthesis in a cell-free system derived from brain.

Science.gov (United States)

Cosgrove, J W; Brown, I R

1984-05-01

An initiating cell-free protein synthesis system derived from brain was utilized to demonstrate that the intravenous injection of D-lysergic acid diethylamide (LSD) to rabbits resulted in a lesion at the initiation stage of brain protein synthesis. Three inhibitors of initiation, edeine, poly(I), and aurintricarboxylic acid were used to demonstrate a reduction in initiation-dependent amino acid incorporation in the brain cell-free system. One hour after LSD injection, there was also a measurable decrease in the formation of 40S and 80S initiation complexes in vitro, using either [35S]methionine or [35S]Met-tRNAf. Analysis of the methionine pool size after LSD administration indicated there was no change in methionine levels. Analysis of the formation of initiation complexes in the brain cell-free protein synthesis system prepared 6 h after LSD administration indicated that there was a return to control levels at this time. The effects of LSD on steps in the initiation process are thus reversible.

Syntheses and structure characterization of ten acid-base hybrid crystals based on imidazole derivatives and mineral acids

Science.gov (United States)

Hu, Kaikai; Deng, Bowen; Jin, Shouwen; Ding, Aihua; Jin, Shide; Zhu, Jin; Zhang, Huan; Wang, Daqi

2018-04-01

Cocrystallization of the imidazole derivatives with a series of mineral acids gave a total of ten hybrid salts with the compositions: [(H2bzm)(Cl)2·3H2O] (1), [(H2bzm)(ClO4)2] (2), [(H2bze)(Cl)2·2H2O] (3), [(H2bze)(Br)2·2H2O] (4), [(H2bzp)(Cl)2·4H2O] (5), [(H2bzp)(Br)2·4H2O] (6), (2-(imidazol-1-yl)-1-phenylethanone): (phosphoric acid) [(Himpeta)+(H2PO4)-] (7), [(H2impd)(Br)2] (8), [(H2impd)(ClO4)2] (9), and [(Hbzml)(Cl)] (10). The ten salts have been characterised by X-ray diffraction analysis, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the ten investigated crystals the ring N atoms of the imidazole are protonated when the acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted classical H-bonds between the NH+ and deprotonated acidic groups. Further analysis of the crystal packing of the salts indicated that a different set of additional CHsbnd O, CH2sbnd O, CHsbnd Cl, CH2sbnd Cl, CHsbnd N, CHsbnd Br, CH2sbnd Br, Osbnd O, O-π, Br-π, CH-π, and π-π associations contribute to the stabilization and expansion of the total high-dimensional frameworks. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical supramolecular synthons, such as R21(7), R22(7), R22(8), and R42(8), usually observed in the organic solids, were again shown to be involved in constructing some of these H-bonding networks.

Radiopharmacology of iminodiacetic acid N-derivatives analysis in biological models and comparison to human beings

International Nuclear Information System (INIS)

Canellas, C.O.; Arguelles, M.G.; Mitta, A.E.A.

1987-01-01

It was studied the influence of chemical structures and molecular weight in the distribution of several iminodiacetic acid N-derivatives and to determine the potential use of these radiopharmaceuticals in humans. The study was performed with the following derivatives: N-(2,6 dimetyphenylcarbamoylmethy) iminodiacetic acid, N(2.6 dietylphenyl-carbamoylmethy) iminodiacetic acid, N-(2,6 diisopropylphenylcarbamoylmethy) iminodiacetic acid and the previously unknown N-derivative N-(2,6 diisopropyl, phenylcarbamoylethyl) iminodiacetic aced. These were sinthesized by a modified procedure by MITTA et al. and controlled by NMR, mass spectrometry, elemental composition and also toxicity pirogens, lethal dose and the chelate's radiochemical dose were determined. Liver gallbladder, intestinal and renal kinetics were studied in mice. In order to evaluate the metabolic pathways of the radiopharmaceuticals, the content of gallbladder and the urine were reinjected. Plasma kinetics and the plasmatic half life was determined by extracorporeal circulation in Wistar rats. For the use in human beings, test were carried out in different branches of nuclear medicine, in normal volunteers and carriers of different pathologic disorders. The patients were divided into four groups: acute and chronic cholecystitis, cirrhosis and jaundice. It was obtained the liver/heart activity ratio and estimated the appearance times of the intrahepatic ducts, gallbladder, duodenum and renal persistence. (M.E.L.) [es

Direct quantitation of the preservatives benzoic and sorbic acid in processed foods using derivative spectrophotometry combined with micro dialysis.

Science.gov (United States)

Fujiyoshi, Tomoharu; Ikami, Takahito; Kikukawa, Koji; Kobayashi, Masato; Takai, Rina; Kozaki, Daisuke; Yamamoto, Atsushi

2018-02-01

The preservatives benzoic acid and sorbic acid are generally quantified with separation techniques, such as HPLC or GC. Here we describe a new method for determining these compounds in processed food samples based on a narrowness of the UV-visible spectral band width with derivative processing. It permits more selective identification and determination of target analytes in matrices. After a sample is purified by micro dialysis, UV spectra of sample solutions were measured and fourth order derivatives of the spectrum were calculated. The amplitude between the maximum and minimum values in a high-order derivative spectrum was used for the determination of benzoic acid and sorbic acid. Benzoic acid and sorbic acid levels in several commercially available processed foods were measured by HPLC and the proposed spectrometry method. The levels obtained by the two methods were highly correlated (r 2 >0.97) for both preservatives. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of drying on caffeoylquinic acid derivative content and antioxidant capacity of sweet potato leaves.

Science.gov (United States)

Jeng, Toong Long; Lai, Chia Chi; Liao, Ting Chen; Lin, Su Yue; Sung, Jih Min

2015-12-01

Caffeoylquinic acid (CQA) derivatives are known to possess antioxidative potential and have many beneficial effects on human health. The present study compared the CQA contents and antioxidant activities of aerial parts of sweet potato plants. The effects of drying methods (freeze drying, and drying at 30°C, 70°C, and 100°C) on these two parameters of the first fully expanded leaves were also assessed. The results indicated that the CQA derivatives were detectable in leaves, stem, and flowers of sweet potato plants (varied from 39.34 mg/g dry weight to 154.05 mg/g dry weight), with the leaves (particularly expanding and first fully expanded leaves) containing more CQA derivatives than other aerial plant parts. The expanding and first fully expanded leaves also exhibited greater antioxidant activities than other aerial plant parts, possibly due to their higher contents of CQA derivatives. Drying method significantly affected the content of CQA derivatives in dried sweet potato leaf tissues. Drying treatments at both 70°C and 100°C significantly reduced the CQA derivative content and antioxidant activity in the first fully expanded leaves. Among the tested drying methods, the freeze-drying method demonstrated the preservation of the highest amount of CQA derivatives (147.84 mg/g) and antioxidant property. However, 30°C cool air drying was also a desirable choice (total CQA derivative content was reduced to only 129.52 mg/g), compared to 70°C and 100°C hot air drying, for commercial-scale processing of sweet potato leaves, if the higher operation cost of freeze drying was a major concern. Copyright © 2014. Published by Elsevier B.V.

Silica-Supported Polyphosphoric Acid in the Synthesis of 4-Substituted Tetrahydroisoquinoline Derivatives

Directory of Open Access Journals (Sweden)

Iliyan Ivanov

2013-02-01

Full Text Available We report herein an application of an α-amidoalkylation reaction, as an alternative efficient synthesis of 4-aryl- and 4-methyl-1,2,3,4-tetrahydroisoquinoline derivatives. The amides required for this purpose would result from reaction of aminoacetaldehyde dimethylacetal with different substituted benzenes in polyphosphoric acid, followed by acylation of the obtained amines with different acid chlorides or sulfochlorides. We compared the cyclisation step using conventional (milieu of acetic-trifluoracetic acid = 4:1 and solid supported reagents (SiO2/PPA, as recovered, regenerated and reused without loss of its activity catalyst. We found that in comparison to conventional methods, the yields of the reaction are greater and the reaction time is shorter.

Effect of the structure of gallic acid and its derivatives on their interaction with plant ferritin.

Science.gov (United States)

Wang, Qunqun; Zhou, Kai; Ning, Yong; Zhao, Guanghua

2016-12-15

Gallic acid and its derivatives co-exist with protein components in foodstuffs, but there is few report on their interaction with proteins. On the other hand, plant ferritin represents not only a novel class of iron supplement, but also a new nanocarrier for encapsulation of bioactive nutrients. However, plant ferritin is easy to be degraded by pepsin in the stomach, thereby limiting its application. Herein, we investigated the interaction of gallic acid and its derivatives with recombinant soybean seed H-2 ferritin (rH-2). We found that these phenolic acids interacted with rH-2 in a structure-dependent manner; namely, gallic acid (GA), methyl gallate (MEGA) and propyl gallate (PG) having three HO groups can bind to rH-2, while their analogues with two HO groups cannot. Consequently, such binding largely inhibited ferritin degradation by pepsin. These findings advance our understanding of the relationship between the structure and function of phenolic acids. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synthesis and radioprotective study of novel amino-alkyl dithiocarbamic acid derivatives against γ-irradiation in mice

International Nuclear Information System (INIS)

Hosseinimehr, S. J.; Beiki, D.; Kebriaeezadeh, A.; Khalaj, A.; Pirali Hamedani, M.; Akhlaghpoor, S.; Esmaeili, H.; Barazesh, A. R.

2009-01-01

The aim of this study was to evaluate the radioprotective capacity of some novel amino alkylated dithiocarbamic acid potassium salts against γ-irradiation in mice. Materials and Methods: Eight compounds containing 2-aminoethyl-, 3-aminopropyl-, 4-aminobutyl-, 5-aminopentyl-, 6-aminohexyl-, 7-amino heptyl-, 8-amino octyl and 9-amino nonyl of dithiocarbamate derivatives were prepared. Male NMRI mice were injected intraperitoneally with a geometric progression of doses (300 -1000 mg/kg), through the dose response range for lethal toxicity. To evaluate the radioprotective activity, one-half of the toxic LD 50 of each compound were injected intraperitoneally to groups of twenty mice, 30 minutes prior to γ-irradiation. The treated animals were kept for 30 days, and the lethality was recorded each day. Results: Among Eight compounds of alkyl dithiocarbamic acid derivatives, 5-aminopentyl, 7-amino heptyl, 8-amino octyl and 9-amino nonyl dithiocarbamic acid mono potassium salts are new compounds. All evaluated compounds showed a concentration dependent effect on the survival in mice. The LD 50 values were found to be more than 599 mg/kg. The percentages of 30-day survival of mice for 2-aminoethyl, 7-amino heptyl and 8-amino octyl dithiocarbamic acid derivatives were 7%, 40% and 13.5%, respectively, when injected 30 minutes before γ-irradiation. Other compounds had no radioprotective effects. Statistical analysis showed a significant difference between the treated and control groups for the 7-amino heptyl derivative (p<0.05). Conclusion: Among the compounds investigated in this study, 7-amino heptyl dithiocarbamate derivative showed more radioprotective effects in comparison with the others. Although it seems that the radioprotective effects in these derivatives correlate with the size of the alkyl chain, more experiments are required to support this hypothesis.

Design, synthesis, molecular docking, anti-Proteus mirabilis and urease inhibition of new fluoroquinolone carboxylic acid derivatives.

Science.gov (United States)

Abdullah, Mohammed A A; Abuo-Rahma, Gamal El-Din A A; Abdelhafez, El-Shimaa M N; Hassan, Heba A; Abd El-Baky, Rehab M

2017-02-01

New hydroxamic acid, hydrazide and amide derivatives of ciprofloxacin in addition to their analogues of levofloxacin were prepared and identified by different spectroscopic techniques. Some of the prepared compounds revealed good activity against the urease splitting bacteria, Proteus mirabilis. The urease inhibitory activity was investigated using indophenol method. Most of the tested compounds showed better activity than the reference acetohydroxamic acid (AHA). The ciprofloxacin hydrazide derivative 3a and levofloxacin hydroxamic acid 7 experienced the highest activity (IC 50 =1.22μM and 2.20μM, respectively). Molecular docking study revealed high spontaneous binding ability of the tested compounds to the active site of urease. Copyright © 2016 Elsevier Inc. All rights reserved.

Synthesis and antifungal activity of new salicylic acid derivatives

Directory of Open Access Journals (Sweden)

Wodnicka Alicja

2017-03-01

Full Text Available A simple one-step procedure for synthesis of 1-methoxy-1-oxoalkan-2-yl salicylates and 1-methoxy-1-oxoalkan-2-yl 2-[(1-methoxy-1-oxoalkan-2-yloxy]benzoates by reaction of salicylic acid with several methyl 2-bromoalkanoates was developed. The reactions were carried out in N,N-dimethylformamide (DMF in the presence of anhydrous potassium carbonate. Conditions for regioselective synthesis of target compounds were established. The developed procedure could be easily applied in the industrial production process. The new salicylic acid derivatives were obtained with satisfactory yields and were characterized by MS and 1H NMR spectra. The fungicidal activity of the prepared compounds was tested in vitro against seven species of plant pathogenic fungi. The best results were observed for 1-methoxy-1-oxoalkan-2-yl salicylates which showed moderate or good activity against Botrytis cinerea and Rhizoctonia solani.

Broad in vitro efficacy of plant-derived betulinic acid against cell lines derived from the most prevalent human cancer types

NARCIS (Netherlands)

Kessler, Jan H.; Mullauer, Franziska B.; de Roo, Guido M.; Medema, Jan Paul

2007-01-01

Betulinic acid (BA) is a widely available plant-derived triterpene with reported activity against cancer cells of neuroectodermal origin and leukaemias. Treatment with BA was shown to protect mice against transplanted human melanoma and led to tumor regression. In contrast, cells from healthy

Formation of novel polymeric films derived from 4-hydroxybenzoic acid

International Nuclear Information System (INIS)

Ferreira, Lucas F.; Souza, Leticia M.; Franco, Diego L.; Castro, Ana C.H.; Oliveira, Alex A.; Boodts, Julien F.C.; Brito-Madurro, Ana G.; Madurro, Joao M.

2011-01-01

Highlights: → Graphite electrodes modified with poly(4-hydroxybenzoic acid) prepared in pH 0.5, 7.0 and 12.0. → Electron transport was higher in poly(4-hydroxybenzoic acid) prepared in acid medium. → Poly(4-HBA) prepared in pH 12.0 presents higher charge transfer resistance. → Polymers prepared in pH 0.5 and 7.0 present globular morphology and in pH 0.5 higher roughness. - Abstract: This work reports electrochemical and morphological studies of formation of poly(4-hydroxybenzoic acid), prepared in different pH, on the graphite surface. Cyclic voltammetry, electrochemical impedance spectroscopy (EIS), electrochemical quartz crystal microbalance (EQCM) and atomic force microscopy (AFM) have been carried out to study the modified electrodes formed. The electrodes modified with poly(4-HBA), prepared in pH 0.5 and 7.0, presented oxidation/reduction peaks, but no peak was detected to modified electrodes prepared in pH 12.0. Voltammetric studies showed decrease in oxidation/reduction currents and slower electron transport across the polymer for all pH values, however, the electron transport was higher when the polymer was prepared in acid medium. EIS analysis indicated that the charge transfer resistance for poly(4-HBA) electropolymerized at pH 12.0 was about 2 and 1.4 times higher when compared to pH 0.5 and 7.0, respectively. Studies through EQCM showed higher amount of polymer mass deposited in acid medium. Images by AFM indicated that the topography is affected by pH value, whereas films prepared in acidic pH conditions presented higher roughness.

Plasmodium falciparum-Derived Uric Acid Precipitates Induce Maturation of Dendritic Cells

Science.gov (United States)

van de Hoef, Diana L.; Coppens, Isabelle; Holowka, Thomas; Ben Mamoun, Choukri; Branch, OraLee; Rodriguez, Ana

2013-01-01

Malaria is characterized by cyclical fevers and high levels of inflammation, and while an early inflammatory response contributes to parasite clearance, excessive and persistent inflammation can lead to severe forms of the disease. Here, we show that Plasmodium falciparum-infected erythrocytes contain uric acid precipitates in the cytoplasm of the parasitophorous vacuole, which are released when erythrocytes rupture. Uric acid precipitates are highly inflammatory molecules that are considered a danger signal for innate immunity and are the causative agent in gout. We determined that P. falciparum-derived uric acid precipitates induce maturation of human dendritic cells, increasing the expression of cell surface co-stimulatory molecules such as CD80 and CD86, while decreasing human leukocyte antigen-DR expression. In accordance with this, uric acid accounts for a significant proportion of the total stimulatory activity induced by parasite-infected erythrocytes. Moreover, the identification of uric acid precipitates in P. falciparum- and P. vivax-infected erythrocytes obtained directly from malaria patients underscores the in vivo and clinical relevance of our findings. Altogether, our data implicate uric acid precipitates as a potentially important contributor to the innate immune response to Plasmodium infection and may provide a novel target for adjunct therapies. PMID:23405174

Salt-inducible promoter derivable from a lactic acid bacterium, and its use in a lactic acid bacterium for production of a desired protein

NARCIS (Netherlands)

Sanders, Jan Willem; Kok, Jan; Venema, Gerard; Ledeboer, Adrianus Marinus

1998-01-01

The invention provides a salt-inducible promoter present in SEQ ID NO: 10 and derivable from a lactic acid bacterium in isolation from the coding sequence normally controlled by said promoter in a wild-type lactic acid bacterium, with modifications and important parts thereof. Also provided are a

Identification of gut-derived metabolites of maslinic acid, a bioactive compound from Olea europaea L.

Science.gov (United States)

Lozano-Mena, Glòria; Sánchez-González, Marta; Parra, Andrés; Juan, M Emília; Planas, Joana M

2016-09-01

Maslinic acid has been described to exert a chemopreventive activity in colon cancer. Hereby, we determined maslinic acid and its metabolites in the rat intestine previous oral administration as a first step in elucidating whether this triterpene might be used as a nutraceutical. Maslinic acid was orally administered at 1, 2, and 5 mg/kg to male Sprague-Dawley for 2 days. At 24 h after the last administration, the content of the duodenum and jejunum, ileum, cecum, and colon was collected and extracted with methanol 80% prior to LC-APCI-MS analysis. The developed method was validated providing suitable sensitivity (LOQ of 5 nM), good recovery (97.8 ± 3.6%), linear correlation, and appropriate precision (< 9%). Maslinic acid was detected in all the segments with higher concentrations in the distal part of the intestine. LC-APCI-LTQ-ORBITRAP-MS allowed the identification of 11 gut-derived metabolites that were formed by mono-, dihydroxylation, and dehydrogenation reactions. Maslinic acid undergoes phase I reactions resulting in a majority of monohydroxylated metabolites without the presence of phase II derivatives. The high concentration of maslinic acid achieved in the intestine suggests that it could exert a beneficial effect in the prevention of colon cancer. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Stereoselective synthesis of functionalized cyclic amino acid derivatives via a [2,3]-Stevens rearrangement and ring-closing metathesis.

Science.gov (United States)

Nash, Aaron; Soheili, Arash; Tambar, Uttam K

2013-09-20

Unnatural cyclic amino acids are valuable tools in biomedical research and drug discovery. A two-step stereoselective strategy for converting simple glycine-derived aminoesters into unnatural cyclic amino acid derivatives has been developed. The process includes a palladium-catalyzed tandem allylic amination/[2,3]-Stevens rearrangement followed by a ruthenium-catalyzed ring-closing metathesis. The [2,3]-rearrangement proceeds with high diastereoselectivity through an exo transition state. Oppolzer's chiral auxiliary was utilized to access an enantiopure cyclic amino acid by this approach, which will enable future biological applications.

Phenolic Acids, Phenolic Aldehydes and Furanic Derivatives in Oak Chips: American vs. French Oaks

OpenAIRE

Cabrita, M.J.; Barrocas Dias, C.; Costa Freitas, A.M.

2011-01-01

Phenolic acids (gallic, vanillic, syringic and ellagic acids), phenolic aldehydes (vanillin, syringaldehyde, coniferaldehyde and sinapaldehyde) and furanic derivatives (furfural, 5-methylfurfural and 5-hydroxymethylfurfural) were quantified in commercial American and French oak chips. Chips with different sizes and toast degrees were used. Compounds were extracted directly from the wood samples in order to determine possible differences among woods as well as toast degree. Likewise, the compo...

Oleaginous yeast Yarrowia lipolytica culture with synthetic and food waste-derived volatile fatty acids for lipid production.

Science.gov (United States)

Gao, Ruiling; Li, Zifu; Zhou, Xiaoqin; Cheng, Shikun; Zheng, Lei

2017-01-01

The sustainability of microbial lipids production from traditional carbon sources, such as glucose or glycerol, is problematic given the high price of raw materials. Considerable efforts have been directed to minimize the cost and find new alternative carbon sources. Volatile fatty acids (VFAs) are especially attractive raw materials, because they can be produced from a variety of organic wastes fermentation. Therefore, the use of volatile fatty acids as carbon sources seems to be a feasible strategy for cost-effective microbial lipid production. Lipid accumulation in Y. lipolytica using synthetic and food waste-derived VFAs as substrates was systematically compared and evaluated in batch cultures. The highest lipid content obtained with acetic, butyric, and propionic acids reached 31.62 ± 0.91, 28.36 ± 0.74, and 28.91 ± 0.66%, respectively. High concentrations of VFA inhibited cell growth in the following order: butyric acid > propionic acid > acetic acid. Within a 30-day experimental period, Y. lipolytica could adapt up to 20 g/L acetic acid, whereas the corresponding concentration of propionic acid and butyric acid were 10 and 5 g/L, respectively. Cultures on a VFA mixture showed that the utilization of different types of VFA by Y. lipolytica was not synchronized but rather performed in a step-wise manner. Although yeast fermentation is an exothermic process, and the addition of VFA will directly affect the pH of the system by increasing environmental acidity, cultures at a cultivation temperature of 38 °C and uncontrolled pH demonstrated that Y. lipolytica had high tolerance in the high temperature and acidic environment when a low concentration (2.5 g/L) of either synthetic or food waste-derived VFA was used. However, batch cultures fed with food fermentate yielded lower lipid content (18.23 ± 1.12%) and lipid productivity (0.12 ± 0.02 g/L/day). The lipid composition obtained with synthetic and food waste-derived VFA was similar to

CT-derived indices of canine osteosarcoma-affected antebrachial strength.

Science.gov (United States)

Garcia, Tanya C; Steffey, Michele A; Zwingenberger, Allison L; Daniel, Leticia; Stover, Susan M

2017-05-01

To improve the prediction of fractures in dogs with bone tumors of the distal radius by identifying computed tomography (CT) indices that correlate with antebrachial bone strength and fracture location. Prospective experimental study. Dogs with antebrachial osteosarcoma (n = 10), and normal cadaver bones (n=9). Antebrachia were imaged with quantitative CT prior to biomechanical testing to failure. CT indices of structural properties were compared to yield force and maximum force using Pearson correlation tests. Straight beam failure (Fs), axial rigidity, curved beam failure (Fc), and craniocaudal bending moment of inertia (MOICrCd) CT indices most highly correlated (0.77 > R > 0.57) with yield and maximum forces when iOSA-affected and control bones were included in the analysis. Considering only OSA-affected bones, Fs, Fc, and axial rigidity correlated highly (0.85 > R > 0.80) with maximum force. In affected bones, the location of minimum axial rigidity and maximum MOICrCd correlated highly (R > 0.85) with the actual fracture location. CT-derived axial rigidity, Fs, and MOICrCd have strong linear relationships with yield and maximum force. These indices should be further evaluated prospectively in OSA-affected dogs that do, and do not, experience pathologic fracture. © 2017 The American College of Veterinary Surgeons.

The antimicrobial efficacy and structure activity relationship of novel carbohydrate fatty acid derivatives against Listeria spp. and food spoilage microorganisms.

Science.gov (United States)

Nobmann, Patricia; Smith, Aoife; Dunne, Julie; Henehan, Gary; Bourke, Paula

2009-01-15

Novel mono-substituted carbohydrate fatty acid (CFA) esters and ethers were investigated for their antibacterial activity against a range of pathogenic and spoilage bacteria focussing on Listeria monocytogenes. Carbohydrate derivatives with structural differences enable comparative studies on the structure/activity relationship for antimicrobial efficacy and mechanism of action. The antimicrobial efficacy of the synthesized compounds was compared with commercially available compounds such as monolaurin and monocaprylin, as well as the pure free fatty acids, lauric acid and caprylic acid, which have proven antimicrobial activity. Compound efficacy was compared using an absorbance based broth microdilution assay to determine the minimum inhibitory concentration (MIC), increase in lag phase and decrease in maximum growth rate. Among the carbohydrate derivatives synthesized, lauric ether of methyl alpha-d-glucopyranoside and lauric ester of methyl alpha-d-mannopyranoside showed the highest growth-inhibitory effect with MIC values of 0.04 mM, comparable to monolaurin. CFA derivatives were generally more active against Gram positive bacteria than Gram negative bacteria. The analysis of both ester and ether fatty acid derivatives of the same carbohydrate, in tandem with alpha and beta configuration of the carbohydrate moiety suggest that the carbohydrate moiety is involved in the antimicrobial activity of the fatty acid derivatives and that the nature of the bond also has a significant effect on efficacy, which requires further investigation. This class of CFA derivatives has great potential for developing antibacterial agents relevant to the food industry, particularly for control of Listeria or other Gram-positive pathogens.

Mono-N-acyl-2,6-diaminopimelic acid derivatives: analysis by electromigration and spectroscopic methods and examination of enzyme inhibitory activity.

Science.gov (United States)

Hlaváček, Jan; Vítovcová, Miloslava; Sázelová, Petra; Pícha, Jan; Vaněk, Václav; Buděšínský, Miloš; Jiráček, Jiří; Gillner, Danuta M; Holz, Richard C; Mikšík, Ivan; Kašička, Václav

2014-12-15

Thirteen mono-N-acyl derivatives of 2,6-diaminopimelic acid (DAP)-new potential inhibitors of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE; EC 3.5.1.18)-were analyzed and characterized by infrared (IR) and nuclear magnetic resonance (NMR) spectroscopies and two capillary electromigration methods: capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC). Structural features of DAP derivatives were characterized by IR and NMR spectroscopies, whereas CZE and MEKC were applied to evaluate their purity and to investigate their electromigration properties. Effective electrophoretic mobilities of these compounds were determined by CZE in acidic and alkaline background electrolytes (BGEs) and by MEKC in acidic and alkaline BGEs containing a pseudostationary phase of anionic detergent sodium dodecyl sulfate (SDS) or cationic detergent cetyltrimethylammonium bromide (CTAB). The best separation of DAP derivatives, including diastereomers of some of them, was achieved by MEKC in an acidic BGE (500 mM acetic acid [pH 2.54] and 60mM SDS). All DAP derivatives were examined for their ability to inhibit catalytic activity of DapE from Haemophilus influenzae (HiDapE) and ArgE from Escherichia coli (EcArgE). None of these DAP derivatives worked as an effective inhibitor of HiDapE, but one derivative-N-fumaryl, Me-ester-DAP-was found to be a moderate inhibitor of EcArgE, thereby providing a promising lead structure for further studies on ArgE inhibitors. Copyright © 2014 Elsevier Inc. All rights reserved.

Omega-3 Fatty Acids and a Novel Mammary Derived Growth Inhibitor Fatty Acid Binding Protein MRG in Suppression of Mammary Tumor

National Research Council Canada - National Science Library

Liu, Yiliang

2001-01-01

We have previously identified and characterized a novel tumor growth inhibitor and a fatty acid binding protein in human mammary gland and named it as Mammary derived growth inhibitor Related Gene MRG...

Peptaibols, tetramic acid derivatives, isocoumarins, and sesquiterpenes from a Bionectria sp. (MSX 47401).

Science.gov (United States)

Figueroa, Mario; Raja, Huzefa; Falkinham, Joseph O; Adcock, Audrey F; Kroll, David J; Wani, Mansukh C; Pearce, Cedric J; Oberlies, Nicholas H

2013-06-28

An extract of the filamentous fungus Bionectria sp. (MSX 47401) showed both promising cytotoxic activity (>90% inhibition of H460 cell growth at 20 μg/mL) and antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). A bioactivity-directed fractionation study yielded one new peptaibol (1) and one new tetramic acid derivative (2), and the fungus biosynthesized diverse secondary metabolites with mannose-derived units. Five known compounds were also isolated: clonostachin (3), virgineone (4), virgineone aglycone (5), AGI-7 (6), and 5,6-dihydroxybisabolol (7). Compounds 5 and 7 have not been described previously from natural sources. Compound 1 represents the second member of the peptaibol structural class that contains an ester-linked sugar alcohol (mannitol) instead of an amide-linked amino alcohol, and peptaibols and tetramic acid derivatives have not been isolated previously from the same fungus. The structures of the new compounds were elucidated primarily by high-field NMR (950 and 700 MHz), HRESIMS/MS, and chemical degradations (Marfey's analysis). All compounds (except 6) were examined for antibacterial and antifungal activities. Compounds 2, 4, and 5 showed antimicrobial activity against S. aureus and several MRSA isolates.

Selective detection of carbohydrates and their peptide conjugates by ESI-MS using synthetic quaternary ammonium salt derivatives of phenylboronic acids.

Science.gov (United States)

Kijewska, Monika; Kuc, Adam; Kluczyk, Alicja; Waliczek, Mateusz; Man-Kupisinska, Aleksandra; Lukasiewicz, Jolanta; Stefanowicz, Piotr; Szewczuk, Zbigniew

2014-06-01

We present new tags based on the derivatives of phenylboronic acid and apply them for the selective detection of sugars and peptide-sugar conjugates in mass spectrometry. We investigated the binding of phenylboronic acid and its quaternary ammonium salt (QAS) derivatives to carbohydrates and peptide-derived Amadori products by HR-MS and MS/MS experiments. The formation of complexes between sugar or sugar-peptide conjugates and synthetic tags was confirmed on the basis of the unique isotopic distribution resulting from the presence of boron atom. Moreover, incorporation of a quaternary ammonium salt dramatically improved the efficiency of ionization in mass spectrometry. It was found that the formation of a complex with phenylboronic acid stabilizes the sugar moiety in glycated peptides, resulting in simplification of the fragmentation pattern of peptide-derived Amadori products. The obtained results suggest that derivatization of phenylboronic acid as QAS is a promising method for sensitive ESI-MS detection of carbohydrates and their conjugates formed by non-enzymatic glycation or glycosylation.

O-Anisidine as Indicator in Titrimetric Determination of Ascorbic Acid and Isonicotinic Acid Hydrazide in Pharmaceutical Formulations

OpenAIRE

B.S.A.Andrews; B.Sreenivas Rao; Som Shankar Dubey; B.Venkata Kiran

2010-01-01

Inspite of the beautiful red coloured oxidized product of O-anisidine, the studies on its application in analytical techniques are scanty. So, authors have taken up the investigation on the utility of O-anisidine as a new Analytical reagent in the bromatometric-Indicator reaction. The detailed reaction on the potassium bromate and OAnisidine has enabled the authors to utilize O-Anisidine in titration of Ascorbic Acid and Isonicitonic Acid Hydrazide. Suitable conditions has been established wi...

Determination of glycated albumin using boronic acid-derived agarose beads on paper-based devices.

Science.gov (United States)

Ko, Euna; Tran, Van-Khue; Geng, Yanfang; Kim, Min Ki; Jin, Ga Hyun; Son, Seong Eun; Hur, Won; Seong, Gi Hun

2018-01-01

Self-monitoring of glycated albumin (GA), a useful glycemic marker, is an established method for preventing diabetes complications. Here, the paper-based lateral flow assay devices were developed for the sensitive detection of GA and the total human serum albumin (tHSA) in self-monitoring diabetes patients. Boronic acid-derived agarose beads were packed into a hole on a lateral flow channel. These well-coordinated agarose beads were used to capture GA through specific cis-diol interactions and to enhance the colorimetric signals by concentrating the target molecules. The devices exhibited large dynamic ranges (from 10  μ g/ml to 10 mg/ml for GA and from 10 mg/ml to 50 mg/ml for tHSA) and low detection limits (7.1  μ g/ml for GA and 4.7 mg/ml for tHSA), which cover the range of GA concentration in healthy plasma, which is 0.21-1.65 mg/ml (0.6%-3%). In determining the unknown GA concentrations in two commercial human plasma samples, the relative percentage difference between the values found by a standard ELISA kit and those found by our developed devices was 2.62% and 8.80%, which are within an acceptable range. The measurements of GA and tHSA were completed within 20 min for the total sample-to-answer diagnosis, fulfilling the demand for rapid analysis. Furthermore, the recovery values ranged from 99.4% to 110% in device accuracy tests. These results indicate that the developed paper-based device with boronic acid-derived agarose beads is a promising platform for GA and tHSA detection as applied to self-monitoring systems.

The influence of humic acids derived from earthworm-processed organic wastes on plant growth

Energy Technology Data Exchange (ETDEWEB)

Atiyeh, R.M.; Lee, S.; Edwards, C.A.; Arancon, N.Q.; Metzger, J.D. [Ohio State University, Columbus, OH (United States). Soil Ecology Lab.

2002-08-01

Some effects of humic acids, formed during the breakdown of organic wastes by earthworms (vermicomposting), on plant growth were evaluated. In the first experiment, humic acids were extracted from pig manure vermicompost using the classic alkali/acid fractionation procedure and mixed with a soilless container medium (Metro-Mix 360), to provide a range of 0, 50, 100, 150, 200, 250, 500, 1000, 2000 and 4000 mg of humate per kg of dry weight of container medium, and tomato seedlings were grown in the mixtures. In the second experiment, humates extracted from pig manure and food wastes vermicomposts were mixed with vermiculite to provide a range of 0, 50, 125, 250, 500, 1000 and 4000 mg of humate per kg of dry weight of the container medium, and cucumber seedlings were grown in the mixtures. Both tomato and cucumber seedlings were watered daily with a solution containing all nutrients required to ensure that any differences in growth responses were not nutrient-mediated. The incorporation of both types of vermicompost-derived humic acids, into either type of soilless plant growth media, increased the growth of tomato and cucumber plants significantly, in terms of plant heights, leaf areas, shoot and root dry weights. Plant growth increased with increasing concentrations of humic acids incorporated into the medium up to a certain proportion, but this differed according to the plant species, the source of the vermicompost, and the nature of the container medium. Plant growth tended to be increased by treatments of the plants with 50-500 mg/kg humic acids, but often decreased significantly when the concentrations of humic acids derived in the container medium exceeded 500-1000 mg/kg. These growth responses were most probably due to hormone-like activity of humic acids from the vermicomposts or could have been due to plant growth hormones adsorbed onto the humates. (author)

Hybrid Compounds Strategy in the Synthesis of Oleanolic Acid Skeleton-NSAID Derivatives

Directory of Open Access Journals (Sweden)

Anna Pawełczyk

2016-04-01

Full Text Available The current study focuses on the synthesis of several hybrid individuals combining a natural oleanolic acid skeleton and synthetic nonsteroidal anti-inflammatory drug moieties (NSAIDs. It studied structural modifications of the oleanolic acid structure by use of the direct reactivity of hydroxyl or hydroxyimino groups at position C-3 of the triterpenoid skeleton with the carboxylic function of anti-inflammatory drugs leading to new perspective compounds with high potential pharmacological activities. Novel ester- and iminoester-type derivatives of oleanolic unit with the different NSAIDs, such as ibuprofen, aspirin, naproxen, and ketoprofen, were obtained and characterized. Moreover, preliminary research of compounds obtaining structure stability under acidic conditions was examined and the PASS method of prediction of activity spectra for substances was used to estimate the potential biological activity of these compounds.

Synthesis of a metabolically stable modified long-chain fatty acid salt and its photolabile derivative

Energy Technology Data Exchange (ETDEWEB)

Stoll, G.H.; Voges, R.; Gerok, W.; Kurz, G. (Institut fuer Organische Chemie and Biochemie, Universitaet Freiburg (Germany))

1991-05-01

An analogue of the long-chain fatty acid salt, sodium stearate, was synthesized in which the hydrogen atoms at carbons 2, 3, and 18 were replaced by fluorine. The key step in the synthesis was the addition of 3-iodo-2,2,3,3-tetrafluoropropanoic acid amide to 15,15,15-trifluoro-1-pentadecene. Radioactivity was introduced by catalytic reduction of 2,2,3,3,18,18,18-heptafluoro-4-octadecenoic acid amide with carrier-free tritium gas yielding a product with the specific radioactivity of 2.63 TBq/mmol. The resulting 2,2,3,3,18,18,18-heptafluoro-4-octadecenoic acid has a pKa of about 0.5 and is completely dissociated under normal physiological conditions. The fluorinated fatty acid salt analogue is readily taken up into hepatocytes and proved to be metabolically inert. In an approach to the identification of proteins involved in long-chain fatty acid salt transport across membranes and intracellular compartments, the photolabile derivative 11,11-azo-2,2,3,3,18,18,18-heptafluoro(G-3H)octadecanoic acid sodium salt was synthesized with a specific radioactivity of 2.63 TBq/mmol. Photolysis of the photolabile derivative, using a light source with a maximum emission at 350 nm, occurred with a half-life of 1.5 min. The generated carbene reacted with 14C-labeled methanol and acetonitrile with covalent bond formation of 6-13%. Its efficacy for photoaffinity labeling was demonstrated by incorporation into serum albumin, the extracellular fatty acid salt-binding protein, as well as into the intracellular fatty acid salt-binding protein (FABP) of rat liver with the molecular weight of 14,000.

Synthesis and Determination of Acid Dissociation Constants in Dimethyl Sulfoxide–Water Hydroorganic Solvent of 5,5-Diphenylpyrrolidine N-Aroylthiourea Derivatives

Directory of Open Access Journals (Sweden)

Yahya Nural

2017-08-01

Full Text Available Novel 5,5-diphenylpyrrolidineN-aroylthioureas, containing 4-methylbenzoyl, 2-chlorobenzoyl,2,4-dichlorobenzoyl, and2-naphthoyl, were synthesized and their structural analysis was performed using 1H nuclear magnetic resonance (NMR, 13C NMR, Fourier transform infrared spectroscopy, mass spectrometry (MS, and high-resolution MS (HRMS techniques. The acid dissociation constants of the 5,5-diphenylpyrrolidineN-aroylthiourea derivative compounds were determined using Hyperquad computer program for data obtained using potentiometric titration method in 25% (v/v dimethyl sulfoxide–water hydroorganic solvent in the presence of 0.1 mol×L-1 ionic strength of NaCl and in the acidic medium at 25±0.1°C, using sodium hydroxide base as a titrant. Two acid dissociation constants were obtained for 3a, 3b, and 3d, and it was suggested that they were related to N-H and enol groups. Furthermore, three acid dissociation constants obtained for 3a indicated that they were related to N-H, enthiol, and enol groups, and four acid dissociation constants obtained for 3c suggested that they were related to N-H, enthiol, enol, and carboxyl groups.

Synthesis and Antiproliferative Activity of Some Novel Triazole Derivatives from Dehydroabietic Acid

Directory of Open Access Journals (Sweden)

Mariano Walter Pertino

2014-02-01

Full Text Available Dehydroabietic acid (DHA is a naturally occurring diterpene with different and relevant biological activities. Previous studies have shown that some DHA derivatives display antiproliferative activity. However, the reported compounds did not include triazole derivatives. Starting from DHA (8,11,13-abietatrien-18-oic acid, and its alcohol dehydroabietinol (8,11,13-abietatrien-18-ol, four alkyl esters were prepared. The alkyl terpenes were treated with different aromatic azides to synthesize hybrid compounds using click chemistry. Some 16 new DHA hybrids were thus synthesized and their structures were confirmed by spectroscopic and spectrometric means. The antiproliferative activity of the new compounds was assessed towards human cell lines, namely normal lung fibroblasts (MRC-5, gastric epithelial adenocarcinoma (AGS, lung cancer (SK-MES-1 and bladder carcinoma (J82 cells. Better antiproliferative effect was found for compound 5, with an IC50 of 6.1 μM and selectivity on SK-MES-1 cells. Under the same experimental conditions, the IC50 of etoposide, was 1.83 µM.

Spectrophotometric study of the protonation processes of some indole derivatives in sulfuric acid

Directory of Open Access Journals (Sweden)

GORAN M. STOJKOVIC

1999-12-01

Full Text Available The protonation of 3-methylindole, D-tryptophan, 3-formylindole, 3-acetylindole and indolyl-2-carboxylic acid in sulfuric acid media was studied by UV spectro-scopy. The measurement of the absorbance at four selected wavelengths enabled the calculation of the corresponding molar absorptivities. The results were used to calculate the pKa value of the protonated form of the indole derivatives by the Hammett Method. The Hammett postulate (the slope of the plot log [c(BH+/c(B] vs. H should be equal to 1 was tested. The dissociation constants and solvent parameter m* were also obtained by applying the Excess Acidity Method. The position of the additional protons in the protonated compounds is discussed.

Lysine and pipecolic acid and some of their derivatives show anticonvulsant activity, and stimulation of benzodiazepine receptor activity

International Nuclear Information System (INIS)

Chang, Yung-Feng; Gao, Xue-Min

1989-01-01

Benzodiazepines are one of the most widely prescribed drugs in the treatment of anxiety, epilepsy and muscle tension. The natural products lysine and pipecolic acid known to be present in the animal, plant and microorganism, have been shown to be anticonvulsant against pentetrazol (PTZ)-induced seizures in mice. Methyl and ethyl esters of L-lysine and the N-isopropanol derivative of pipecolic acid appear to increase the anticonvulsant potency of the parent compounds, presumably due to their increase in hydrophobicity. Lysine and pipecolic acid showed significant stimulation of specific [ 3 H]flunitrazepam (FZ) binding to mouse brain membranes. This stimulation was enhanced by chloride ions and stereospecific with L-isomer having higher effect. The dose-dependent anticonvulsant activity of lysine and pipecolic acid, and their stimulation of [ 3 H]FZ binding appear to be correlated. The antiepileptic activity lysine, pipecolic acid and their derivatives therefore may be mediated through the γ-aminobutyric acid-benzodiazepine receptor complex

Lanthanide nitrates as Lewis acids in the one-pot synthesis of 1,2,4-oxadiazole derivatives

Energy Technology Data Exchange (ETDEWEB)

Vale, Juliana A.; Faustino, Wagner M., E-mail: julianadqf@yahoo.com.br [Departamento de Quimica, Universidade Federal da Paraiba, Joao Pessoa, PB (Brazil); Zampieri, Davila de S.; Moran, Paulo J.S.; Rodrigues, Jose A.R. [Instituto de Quimica, Universidade Estadual de Campinas, SP (Brazil); Sa, Gilberto F. de [Departamento de Quimica Fundamental, CCEN, Universidade Federal de Pernambuco, Recife, PE (Brazil)

2012-08-15

In this work we report the use of lanthanide nitrates [Ln(NO{sub 3}){sub 3}] acting as catalyst in direct one pot synthesis of 3-benzoyl- and 3-acetyl-1,2,4-oxadiazoles derivatives from ketones, nitriles and nitric acid. This is the first example of one-pot synthesis of benzoyl- and acetyl 1,2,4-oxadiazoles derivatives preparation using acetophenones derivates with electron-donator groups. (author)

D-Lactic acid biosynthesis from biomass-derived sugars via Lactobacillus delbrueckii fermentation.

Science.gov (United States)

Zhang, Yixing; Vadlani, Praveen V

2013-12-01

Poly-lactic acid (PLA) derived from renewable resources is considered to be a good substitute for petroleum-based plastics. The number of poly L-lactic acid applications is increased by the introduction of a stereocomplex PLA, which consists of both poly-L and D-lactic acid and has a higher melting temperature. To date, several studies have explored the production of L-lactic acid, but information on biosynthesis of D-lactic acid is limited. Pulp and corn stover are abundant, renewable lignocellulosic materials that can be hydrolyzed to sugars and used in biosynthesis of D-lactic acid. In our study, saccharification of pulp and corn stover was done by cellulase CTec2 and sugars generated from hydrolysis were converted to D-lactic acid by a homofermentative strain, L. delbrueckii, through a sequential hydrolysis and fermentation process (SHF) and a simultaneous saccharification and fermentation process (SSF). 36.3 g L(-1) of D-lactic acid with 99.8 % optical purity was obtained in the batch fermentation of pulp and attained highest yield and productivity of 0.83 g g(-1) and 1.01 g L(-1) h(-1), respectively. Luedeking-Piret model described the mixed growth-associated production of D-lactic acid with a maximum specific growth rate 0.2 h(-1) and product formation rate 0.026 h(-1), obtained for this strain. The efficient synthesis of D-lactic acid having high optical purity and melting point will lead to unique stereocomplex PLA with innovative applications in polymer industry.

Complete oxidative conversion of lignocellulose derived non-glucose sugars to sugar acids by Gluconobacter oxydans.

Science.gov (United States)

Yao, Ruimiao; Hou, Weiliang; Bao, Jie

2017-11-01

Non-glucose sugars derived from lignocellulose cover approximately 40% of the total carbohydrates of lignocellulose biomass. The conversion of the non-glucose sugars to the target products is an important task of lignocellulose biorefining research. Here we report a fast and complete conversion of the total non-glucose sugars from corn stover into the corresponding sugar acids by whole cell catalysis and aerobic fermentation of Gluconobacter oxydans. The conversions include xylose to xylonate, arabinose to arabonate, mannose to mannonate, and galactose to galactonate, as well as with glucose into gluconate. These cellulosic non-glucose sugar acids showed the excellent cement retard setting property. The mixed cellulosic sugar acids could be used as cement retard additives without separation. The conversion of the non-glucose sugars not only makes full use of lignocellulose derived sugars, but also effectively reduces the wastewater treatment burden by removal of residual sugars. Copyright © 2017 Elsevier Ltd. All rights reserved.

Design, docking, synthesis and anticancer activity of some novel 2-(4-methylbenzenesulphonamidopentanedioic acid amide derivatives

Directory of Open Access Journals (Sweden)

Satyajit Dutta

2014-08-01

Full Text Available In the present work few novel 2-(4-methylbenzenesulphonamidopentanedioic acid amide derivatives and the basic compound 2-(4-methylphenylsulfon-amidopentanedioic acid have been designed, synthesized, characterized and screened for their possible antineoplastic activity both in vitro and in vivo. The modified drugs were docked against the protein histone deacetylase the energy value obtained was o-iodoanilide (-10.370504 and m-iodoanilide (-10.218276 of the titled compound. The in vitro activity was performed against five human cell lines like human breast cancer (MCF-7, leukemia (K-562, ova-rian cancer (OVACAR-3, human colon adenocarcinoma (HT-29 and Human kidney carcinoma (A-498. The in vivo activity was performed in female Swiss albino mice against Ehrlich Ascites Carcinoma (EAC. Among the synthesized compounds, o-iodoanilide, m-iodoanilide and p-iodoanilide derivatives of 2-(4-methyl benzene sulphonyl-pentanedioic acid amides showed encouraging activity in both the in vitro and in vivo compared to other compounds.

Chemical Reaction between Boric Acid and Phosphine Indicates Boric Acid as an Antidote for Aluminium Phosphide Poisoning

Directory of Open Access Journals (Sweden)

Motahareh Soltani

2016-08-01

Full Text Available Objectives: Aluminium phosphide (AlP is a fumigant pesticide which protects stored grains from insects and rodents. When it comes into contact with moisture, AlP releases phosphine (PH3, a highly toxic gas. No efficient antidote has been found for AlP poisoning so far and most people who are poisoned do not survive. Boric acid is a Lewis acid with an empty p orbital which accepts electrons. This study aimed to investigate the neutralisation of PH3 gas with boric acid. Methods: This study was carried out at the Baharlou Hospital, Tehran University of Medical Sciences, Tehran, Iran, between December 2013 and February 2014. The volume of released gas, rate of gas evolution and changes in pH were measured during reactions of AlP tablets with water, acidified water, saturated boric acid solution, acidified saturated boric acid solution, activated charcoal and acidified activated charcoal. Infrared spectroscopy was used to study the resulting probable adduct between PH3 and boric acid. Results: Activated charcoal significantly reduced the volume of released gas (P <0.01. Although boric acid did not significantly reduce the volume of released gas, it significantly reduced the rate of gas evolution (P <0.01. A gaseous adduct was formed in the reaction between pure AlP and boric acid. Conclusion: These findings indicate that boric acid may be an efficient and non-toxic antidote for PH3 poisoning.

flower extract as an improvised indicator in acid – base titration

African Journals Online (AJOL)

USER

laboratory practical with an instructional material that is useful, economical, simple and accurate for the said titration. Therefore, it is recommended for integrated science and chemistry instructions. Keywords: Flower, acid, base, indicator, titration. INTRODUCTION. In Nigeria, factors militating against science education.

Peptidyl prolyl isomerase Pin1-inhibitory activity of D-glutamic and D-aspartic acid derivatives bearing a cyclic aliphatic amine moiety.

Science.gov (United States)

Nakagawa, Hidehiko; Seike, Suguru; Sugimoto, Masatoshi; Ieda, Naoya; Kawaguchi, Mitsuyasu; Suzuki, Takayoshi; Miyata, Naoki

2015-12-01

Pin1 is a peptidyl prolyl isomerase that specifically catalyzes cis-trans isomerization of phosphorylated Thr/Ser-Pro peptide bonds in substrate proteins and peptides. Pin1 is involved in many important cellular processes, including cancer progression, so it is a potential target of cancer therapy. We designed and synthesized a novel series of Pin1 inhibitors based on a glutamic acid or aspartic acid scaffold bearing an aromatic moiety to provide a hydrophobic surface and a cyclic aliphatic amine moiety with affinity for the proline-binding site of Pin1. Glutamic acid derivatives bearing cycloalkylamino and phenylthiazole groups showed potent Pin1-inhibitory activity comparable with that of known inhibitor VER-1. The results indicate that steric interaction of the cyclic alkyl amine moiety with binding site residues plays a key role in enhancing Pin1-inhibitory activity. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Continuous Autoregulatory Indices Derived from Multi-Modal Monitoring: Each One Is Not Like the Other.

Science.gov (United States)

Zeiler, Frederick A; Donnelly, Joseph; Menon, David K; Smielewski, Peter; Zweifel, Christian; Brady, Ken; Czosnyka, Marek

2017-11-15

We assess the relationships between various continuous measures of autoregulatory capacity in a cohort of adults with traumatic brain injury (TBI). We assessed relationships between autoregulatory indices derived from intracranial pressure (ICP: PRx, PAx, RAC), transcranial Doppler (TCD: Mx, Sx, Dx), brain tissue-oxygenation (ORx), and spatially resolved near infrared spectroscopy (NIRS resolved: TOx, THx). Relationships between indices were assessed using Pearson correlation coefficient, Friedman test, principal component analysis (PCA), agglomerative hierarchal clustering (AHC) and k-means cluster analysis (KMCA). All analytic techniques were repeated for a range of temporal resolutions of data, including minute-by-minute averages, moving means of 30 samples, and grand mean for each patient. Thirty-seven patients were studied. The PRx displayed strong association with PAx/RAC across all the analytical techniques: Pearson correlation (r = 0.682/r = 0.677, p indices (Mx, Dx) were correlated and co-clustered on PCA, AHC, and KMCA. The Sx was found to be more closely associated with ICP-derived indices on Pearson correlation, PCA, AHC, and KMCA. The NIRS indices displayed variable correlation with each other and with indices derived from ICP and TCD signals. Of interest, TOx and THx co-cluster with ICP-based indices on PCA and AHC. The ORx failed to display any meaningful correlations with other indices in neither of the analytical method used. Thirty-minute moving average and minute-by-minute data set displayed similar results across all the methods. The RAC, Mx, and Sx were the strongest predictors of outcome at six months. Continuously updating autoregulatory indices are not all correlated with one another. Caution must be advised when utilizing less commonly described autoregulation indices (i.e., ORx) for the clinical assessment of autoregulatory capacity, because they appear to not be related to commonly measured/establish indices, such as PRx

Hydrolysis and rearrangement of phthalamic acid derivatives and assessment of their potential as prodrug forms for amines

DEFF Research Database (Denmark)

Bundgaard, Hans; Steffansen, Bente

1990-01-01

Although it is well-known that N-substituted phthalamic acid derivatives are readily hydrolyzed in acidic aqueous solution due to intramolecular catalysis by the neighbouring carboxy group, sparse information is available on the degradation behaviour in neutral solutions. A recent publication [5]...

5-Arylidene derivatives of Meldrum's acid: Synthesis, structural characterization using single crystal and powder crystal X-ray diffraction, and electronic properties

Science.gov (United States)

Dey, Tanusri; Ghosh, Soumen; Ghosh, Somnath; Mukherjee, Alok Kumar

2015-07-01

Four 5-arylidene derivatives of Meldrum's acid, 5-(4-chlorobenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (2), 5-(3-hydroxybenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (3), 5-(3,4-dimethoxybenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (4) and 5-(2,4-dimethoxy benzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (5) have been synthesized and their crystal structures have been determined using single crystal X-ray diffractometry for 2, 4 and 5 and X-ray powder diffraction for 3. The nature of intermolecular interactions in 2-5 has been analyzed through Hirshfeld surfaces and 2D fingerprint plots. The DFT optimized molecular geometries in 2-5 agree closely with those obtained from the crystallographic studies. The crystal packing in 2-5 exhibits an interplay of Osbnd H⋯O, Csbnd H⋯O, Csbnd H⋯Cl and Csbnd H⋯π (arene) hydrogen bonds and π⋯π interactions, which assemble molecules into three-dimensional architecture in 2, 3 and 5 and two-dimensional framework in 4. The Hirshfeld surface analyses of 2-5, Meldrum's acid (1) and a few related 5-arylidene derivatives of Meldrum's acid retrieved from the Cambridge Structural Database (CSD) indicate that about 85% of the Hirshfeld surface area (72% in 2 where H⋯Cl contribution is about 13%) in this class of compounds are due to H⋯H, O⋯H and C⋯H contacts. The HOMO-LUMO energy gap (>2.2 eV) in 2-5 indicates a significant degree of internal charge transfer within the molecule.

Improving surface functional properties of tofu whey-derived peptides by chemical modification with fatty acids.

Science.gov (United States)

Matemu, Athanasia Oswald; Katayama, Shigeru; Kayahara, Hisataka; Murasawa, Hisashi; Nakamura, Soichiro

2012-04-01

Effect of acylation with saturated fatty acids on surface functional properties of tofu whey-derived peptides was investigated. Tofu whey (TW) and soy proteins (7S, 11S, and acid-precipitated soy protein [APP]) were hydrolyzed by Protease M 'Amano' G, and resulting peptide mixtures were acylated with esterified fatty acids of different chain length (6C to 18C) to form a covalent linkage between the carboxyl group of fatty acid and the free amino groups of peptide. Acylation significantly (P properties of 7S, 11S, and APP peptides independent of fatty acid chain length. Acylation decreased water binding capacity although oil binding capacity of acylated tofu whey ultra filtered fraction (UFTW acids had shown significant higher surface hydrophobicity as in contrast with acylated UFTW acids can further affect functional properties of soy proteins. © 2012 Institute of Food Technologists®

A novel acidic pH fluorescent probe based on a benzothiazole derivative

Science.gov (United States)

Ma, Qiujuan; Li, Xian; Feng, Suxiang; Liang, Beibei; Zhou, Tiqiang; Xu, Min; Ma, Zhuoyi

2017-04-01

A novel acidic pH fluorescent probe 1 based on a benzothiazole derivative has been designed, synthesized and developed. The linear response range covers the acidic pH range from 3.44 to 6.46, which is valuable for pH researches in acidic environment. The evaluated pKa value of the probe 1 is 4.23. The fluorescence enhancement of the studied probe 1 with an increase in hydrogen ions concentration is based on the hindering of enhanced photo-induced electron transfer (PET) process. Moreover, the pH sensor possesses a highly selective response to H+ in the presence of metal ions, anions and other bioactive small molecules which would be interfere with its fluorescent pH response. Furthermore, the probe 1 responds to acidic pH with short response time that was less than 1 min. The probe 1 has been successfully applied to confocal fluorescence imaging in live HeLa cells and can selectively stain lysosomes. All of such good properties prove it can be used to monitoring pH fluctuations in acidic environment with high sensitivity, pH dependence and short response time.

Synthesis and Biological Activity of 3-[Phenyl(1,3-thiazol-2-yl-amino]propanoic Acids and Their Derivatives

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Vytautas Mickevičius

2013-12-01

Full Text Available New N,N-disubstituted β-amino acids and their derivatives with thiazole, aromatic, and heterocyclic substituents were synthesized from N-phenyl-N-thiocarbamoyl-β-alanine by the Hantzsch method; derivatives with hydrazone fragments were also obtained. Some of the synthesized compounds exhibited discrete antimicrobial activity, and 3-[(4-oxo-4,5-dihydro-1,3-thiazol-2-yl(phenylamino]propanoic acid was found to promote rapeseed growth and to increase seed yield and oil content.

Calculating degree-based topological indices of dominating David derived networks

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Ahmad, Muhammad Saeed; Nazeer, Waqas; Kang, Shin Min; Imran, Muhammad; Gao, Wei

2017-12-01

An important area of applied mathematics is the Chemical reaction network theory. The behavior of real world problems can be modeled by using this theory. Due to applications in theoretical chemistry and biochemistry, it has attracted researchers since its foundation. It also attracts pure mathematicians because it involves interesting mathematical structures. In this report, we compute newly defined topological indices, namely, Arithmetic-Geometric index (AG1 index), SK index, SK1 index, and SK2 index of the dominating David derived networks [1, 2, 3, 4, 5].

Deriving Multidimensional Poverty Indicators: Methodological Issues and an Empirical Analysis for Italy

Science.gov (United States)

Coromaldi, Manuela; Zoli, Mariangela

2012-01-01

Theoretical and empirical studies have recently adopted a multidimensional concept of poverty. There is considerable debate about the most appropriate degree of multidimensionality to retain in the analysis. In this work we add to the received literature in two ways. First, we derive indicators of multiple deprivation by applying a particular…

Host-Derived Sialic Acids Are an Important Nutrient Source Required for Optimal Bacterial Fitness In Vivo.

Science.gov (United States)

McDonald, Nathan D; Lubin, Jean-Bernard; Chowdhury, Nityananda; Boyd, E Fidelma

2016-04-12

A major challenge facing bacterial intestinal pathogens is competition for nutrient sources with the host microbiota.Vibrio cholerae is an intestinal pathogen that causes cholera, which affects millions each year; however, our knowledge of its nutritional requirements in the intestinal milieu is limited. In this study, we demonstrated that V. cholerae can grow efficiently on intestinal mucus and its component sialic acids and that a tripartite ATP-independent periplasmic SiaPQM strain, transporter-deficient mutant NC1777, was attenuated for colonization using a streptomycin-pretreated adult mouse model. In in vivo competition assays, NC1777 was significantly outcompeted for up to 3 days postinfection. NC1777 was also significantly outcompeted in in vitro competition assays in M9 minimal medium supplemented with intestinal mucus, indicating that sialic acid uptake is essential for fitness. Phylogenetic analyses demonstrated that the ability to utilize sialic acid was distributed among 452 bacterial species from eight phyla. The majority of species belonged to four phyla, Actinobacteria (members of Actinobacillus, Corynebacterium, Mycoplasma, and Streptomyces), Bacteroidetes (mainly Bacteroides, Capnocytophaga, and Prevotella), Firmicutes (members of Streptococcus, Staphylococcus, Clostridium, and Lactobacillus), and Proteobacteria (including Escherichia, Shigella, Salmonella, Citrobacter, Haemophilus, Klebsiella, Pasteurella, Photobacterium, Vibrio, and Yersinia species), mostly commensals and/or pathogens. Overall, our data demonstrate that the ability to take up host-derived sugars and sialic acid specifically allows V. cholerae a competitive advantage in intestinal colonization and that this is a trait that is sporadic in its occurrence and phylogenetic distribution and ancestral in some genera but horizontally acquired in others. Sialic acids are nine carbon amino sugars that are abundant on all mucous surfaces. The deadly human pathogen Vibrio cholerae contains

Uptake of acidic and basic sugar derivatives in Lemna gibba G1

International Nuclear Information System (INIS)

Sanz, A.; Ullrich, C.I.

1989-01-01

The uptake of acidic and basic sugar derivatives in Lemna gibba L. was studied. Uronic acids applied to the experimental solution induced a small decrease of the membrane potential. After incubation of the plants in a 0.1 millimolar solution of these substrates, no decrease in the concentration of reducing groups in the external solution was detected. Respiration increased by 31% with 50 millimolar galacturonic acid, whereas no effect was found with the same concentration of glucuronic acid. Glucosamine caused a considerable concentration-dependent membrane depolarization. ( 14 C)glucosamine uptake followed Michaelis-Menten kinetics together with a linear component. Influx of this substrate was inhibited by glucose but the type of competition could not be clearly distinguished. Glucosamine, 50 millimolar, inhibited the respiration rate by 30%. The glucosamine uptake was pH-dependent, with maximum uptake at around pH 7. Lack of enhancement of uptake by low pH as well as the permanent membrane depolarization suggest a uniport mechanism for the charged species of the substrate and an electroneutral diffusion of the uncharged species

Kinetics and Optimization of Lipophilic Kojic Acid Derivative Synthesis in Polar Aprotic Solvent Using Lipozyme RMIM and Its Rheological Study

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Nurazwa Ishak

2018-02-01

Full Text Available The synthesis of kojic acid derivative (KAD from kojic and palmitic acid (C16:0 in the presence of immobilized lipase from Rhizomucor miehei (commercially known as Lipozyme RMIM, was studied using a shake flask system. Kojic acid is a polyfunctional heterocycles that acts as a source of nucleophile in this reaction allowing the formation of a lipophilic KAD. In this study, the source of biocatalyst, Lipozyme RMIM, was derived from the lipase of Rhizomucor miehei immobilized on weak anion exchange macro-porous Duolite ES 562 by the adsorption technique. The effects of solvents, enzyme loading, reaction temperature, and substrate molar ratio on the reaction rate were investigated. In one-factor-at-a-time (OFAT experiments, a high reaction rate (30.6 × 10−3 M·min−1 of KAD synthesis was recorded using acetone, enzyme loading of 1.25% (w/v, reaction time of 12 h, temperature of 50 °C and substrate molar ratio of 5:1. Thereafter, a yield of KAD synthesis was optimized via the response surface methodology (RSM whereby the optimized molar ratio (fatty acid: kojic acid, enzyme loading, reaction temperature and reaction time were 6.74, 1.97% (w/v, 45.9 °C, and 20 h respectively, giving a high yield of KAD (64.47%. This condition was reevaluated in a 0.5 L stirred tank reactor (STR where the agitation effects of two impellers; Rushton turbine (RT and pitch-blade turbine (PBT, were investigated. In the STR, a very high yield of KAD synthesis (84.12% was achieved using RT at 250 rpm, which was higher than the shake flask, thus indicating better mixing quality in STR. In a rheological study, a pseudoplastic behavior of KAD mixture was proposed for potential application in lotion formulation.

Kinetics and Optimization of Lipophilic Kojic Acid Derivative Synthesis in Polar Aprotic Solvent Using Lipozyme RMIM and Its Rheological Study.

Science.gov (United States)

Ishak, Nurazwa; Lajis, Ahmad Firdaus B; Mohamad, Rosfarizan; Ariff, Arbakariya B; Mohamed, Mohd Shamzi; Halim, Murni; Wasoh, Helmi

2018-02-24

The synthesis of kojic acid derivative (KAD) from kojic and palmitic acid (C16:0) in the presence of immobilized lipase from Rhizomucor miehei (commercially known as Lipozyme RMIM), was studied using a shake flask system. Kojic acid is a polyfunctional heterocycles that acts as a source of nucleophile in this reaction allowing the formation of a lipophilic KAD. In this study, the source of biocatalyst, Lipozyme RMIM, was derived from the lipase of Rhizomucor miehei immobilized on weak anion exchange macro-porous Duolite ES 562 by the adsorption technique. The effects of solvents, enzyme loading, reaction temperature, and substrate molar ratio on the reaction rate were investigated. In one-factor-at-a-time (OFAT) experiments, a high reaction rate (30.6 × 10 -3 M·min -1 ) of KAD synthesis was recorded using acetone, enzyme loading of 1.25% ( w / v ), reaction time of 12 h, temperature of 50 °C and substrate molar ratio of 5:1. Thereafter, a yield of KAD synthesis was optimized via the response surface methodology (RSM) whereby the optimized molar ratio (fatty acid: kojic acid), enzyme loading, reaction temperature and reaction time were 6.74, 1.97% ( w / v ), 45.9 °C, and 20 h respectively, giving a high yield of KAD (64.47%). This condition was reevaluated in a 0.5 L stirred tank reactor (STR) where the agitation effects of two impellers; Rushton turbine (RT) and pitch-blade turbine (PBT), were investigated. In the STR, a very high yield of KAD synthesis (84.12%) was achieved using RT at 250 rpm, which was higher than the shake flask, thus indicating better mixing quality in STR. In a rheological study, a pseudoplastic behavior of KAD mixture was proposed for potential application in lotion formulation.

Antitumor activity of newly synthesized oxo and ethylidene derivatives of bile acids and their amides and oxazolines.

Science.gov (United States)

Bjedov, Srđan; Jakimov, Dimitar; Pilipović, Ana; Poša, Mihalj; Sakač, Marija

2017-04-01

Bile acid derivatives with modifications in side chain and modifications on steroid skeleton were synthetized and their antitumor activity against five human cancer cell lines was investigated. Modifications in side chain include amid group, formed in reaction with 2-amino-2-methylpropanol, and 4,4-dimethyloxazoline group, obtained after cyclization of amides. In the steroid skeleton oxo groups were introduced in position 7 (2, 2a, 2b) and 7,12 (3, 3a, 3b). Ethylidene groups were introduced regio- and stereoselectively on C-7, and/or without stereoselectivity on C-3 by Wittig reaction. By combination of these modifications, a series of 19 bile acid derivatives were synthesized. Compounds containing both C-7 ethylidene and C-12 carbonyl groups (6, 6a, 6b) shown very good antitumor activity with IC 50 amide or oxazoline group has positive effect on cytotoxicity. Different molecular descriptors were determined in silico and after principal component analysis was found that molecular descriptor BLTF96 can be used for fast assessment of experimental cytotoxicity of bile acid derivatives. Copyright © 2017 Elsevier Inc. All rights reserved.

Chemical functionalization of hyaluronic acid for drug delivery applications

Energy Technology Data Exchange (ETDEWEB)

Vasi, Ana-Maria [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 73 Prof. dr. docent Dimitrie Mangeron Street, 700050 Iasi (Romania); Popa, Marcel Ionel, E-mail: mipopa@ch.tuiasi.ro [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 73 Prof. dr. docent Dimitrie Mangeron Street, 700050 Iasi (Romania); Butnaru, Maria [“Grigore T. Popa” University of Medicine Pharmacy, Faculty of Medical Bioengineering, 9-13 Kogalniceanu Street, 700454 Iasi (Romania); Dodi, Gianina [“Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 73 Prof. dr. docent Dimitrie Mangeron Street, 700050 Iasi (Romania); SCIENT — Research Center for Instrumental Analysis, S.C. CROMATEC PLUS, 18 Sos. Cotroceni, 060114 Bucharest (Romania); Verestiuc, Liliana [“Grigore T. Popa” University of Medicine Pharmacy, Faculty of Medical Bioengineering, 9-13 Kogalniceanu Street, 700454 Iasi (Romania)

2014-05-01

Functionalized hyaluronic acid (HA) derivatives were obtained by ring opening mechanism of maleic anhydride (MA). FTIR and H{sup 1} NMR spectroscopy were used to confirm the chemical linkage of MA on the hyaluronic acid chains. Thermal analysis (TG-DTG and DSC) and GPC data for the new products revealed the formation of new functional groups, without significant changes in molecular weight and thermal stability. New gels based on hyaluronic acid modified derivatives were obtained by acrylic acid copolymerization in the presence of a redox initiation system. The resulted circular and interconnected pores of the gels were visualized by SEM. The release profiles of an ophthalmic model drug, pilocarpine from tested gels were studied in simulated media. Evaluation of the cytotoxicity and cell proliferation properties indicates the potential of the new systems to be used in contact with biological media in drug delivery applications. - Highlights: • New functionalized hyaluronic acid was prepared by ring opening of maleic anhydride. • Gels with circular pores based on acrylic acid copolymerization were formulated. • In vitro drug loading/release profile was evaluated in simulated ophthalmic media. • The cytotoxicity indicates the potential of derivatives to be used in vivo.

Relationships between indicators of acid-base chemistry and fish assemblages in streams of the Great Smoky Mountains National Park

Science.gov (United States)

Baldigo, Barry P.; Kulp, Matt A.; Schwartz, John S.

2018-01-01

The acidity of many streams in the Great Smoky Mountains National Park (GRSM) has increased significantly since pre-industrial (∼1850) times due to the effects of highly acidic atmospheric deposition in poorly buffered watersheds. Extensive stream-monitoring programs since 1993 have shown that fish and macroinvertebrate assemblages have been adversely affected in many streams across the GRSM. Matching chemistry and fishery information collected from 389 surveys performed at 52 stream sites over a 22-year period were assessed using logistic regression analysis to help inform the U.S. Environmental Protection Agency’s assessment of the environmental impacts of emissions of oxides of nitrogen (NOx) and sulfur (SOx). Numerous logistic equations and associated curves were derived that defined the relations between acid neutralizing capacity (ANC) or pH and different levels of community richness, density, and biomass; and density and biomass of brook trout, rainbow trout, and small prey (minnow) populations in streams of the GRSM. The equations and curves describe the status of fish assemblages in the GRSM under contemporary emission levels and deposition loads of nitrogen (N) and sulfur (S) and provide a means to estimate how newly proposed (and various alternative) target deposition loads, which strongly influence stream ANC, might affect key ecological indicators. Several examples using ANC, community richness, and brook trout density are presented to illustrate the steps needed to predict how future changes in stream chemistry (resulting from different target deposition loads of N and S) will affect the probabilities of observing specific levels of selected biological indicators in GRSM streams. The implications of this study to the regulation of NOx and SOx emissions, water quality, and fisheries management in streams of the GRSM are discussed, but also qualified by the fact that specific examples provided need to be further explored before recommendations

Strecker degradation of amino acids promoted by a camphor-derived sulfonamide

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M. Fernanda N. N. Carvalho

2016-04-01

Full Text Available A camphor-derived sulfonimine with a conjugated carbonyl group, oxoimine 1 (O2SNC10H13O, reacts with amino acids (glycine, L-alanine, L-phenylalanine, L-leucine to form a compound O2SNC10H13NC10H14NSO2 (2 which was characterized by spectroscopic means (MS and NMR and supported by DFT calculations. The product, a single diastereoisomer, contains two oxoimine units connected by a –N= bridge, and thus has a structural analogy to the colored product Ruhemann´s purple obtained by the ninhydrin reaction with amino acids. A plausible reaction mechanism that involves zwitterions, a Strecker degradation of an intermediate imine and water-catalyzed tautomerizations was developed by means of DFT calculations on potential transition states.

Comparison of inhibition effects of some benzoic acid derivatives on sheep heart carbonic anhydrase

Science.gov (United States)

Kiliç, Deryanur; Yildiz, Melike; Şentürk, Murat; Erdoǧan, Orhan; Küfrevioǧlu, Ömer Irfan

2016-04-01

Carbonic anhydrase (CA) is a family of metalloenzymes that requires Zn as a cofactor and catalyze the quick conversion of CO2 to HCO3- and H+. Inhibitors of the carbonic anhydrases (CAs) have medical usage of significant diseases such as glaucoma, epilepsy, gastroduodenal ulcers, acid-base disequilibria and neurological disorders. In the present study, inhibition of CA with some benzoic derivatives (1-6) were investigated. Sheep heart CA (shCA) enzyme was isolated by means of designed affinity chromatography gel (cellulose-benzyl-sulfanylamide) 42.45-fold in a yield of 44 % with 564.65 EU/mg. Purified shCA enzyme was used in vitro studies. In the studies, IC50 values were calculated for 3-aminobenzoic acid (1), 4-aminobenzoic acid (2), 2-hydroxybenzoic acid (3), 2-benzoylbenzoic acid (4), 2,3-dimethoxybenzoic acid (5), and 3,4,5-trimethoxybenzoic acid (6), showing the inhibition effects on the purified enzyme. Such molecules can be used as pioneer for discovery of novel effective CA inhibitors for medicinal chemistry applications.

Synthesis and physical-chemical properties of functional derivatives of 3-benzyl-8-propylxanthinyl-7-acetic acid

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E. K. Mikhal’chenko

2017-08-01

Full Text Available Introduction. Synthetic research of new biologically active compounds occupies an important place in modern pharmaceutical science.Thus it is important to develop techniques for the biologically active substances functionalization. Esters and amides take special place among the variety of functional derivatives of organic acids,. These fragments are well-known pharmacophores and could be found in a wide range of drugs. Thus, the nootropic agent pyracetam is 2-oxo-1-pyrolidineacetamide, and is the selective antagonist of β-adrenoreceptores; atenolol is a derivative of benzeneacetamide. Substituted acetamide and ester fragments are also present in the structures of aprofen, spasmolitin, acetylidine and β-lactam cephalosporins and penicillins antibiotics.Aim of our research was the synthetic method development for functional derivatives of 3-benzyl-8-propylxanthinyl-7-acetic acid and the study of their physical-chemical properties. Materials and methods. Melting points were determined using capillary method on DMP (M. 1Н NMR-spectra were recorded by Varian Mercury VX-200 device (company «Varian» – USA solvent – (DMSO-d6, internal standard – ТМS. Elemental analysis of obtained compounds was produced on device Elementar Vario L cube. Chemical shifts were reported in ppm (parts per million values. Infrared (IR spectra were measured on a Bruker Alpha instrument using a potassium bromide (KBr disk, scanning from 400 to 4000 cm-1. Results and discussion. We selected 3-benzyl-8-propylxanthinyl-7-acetic acid as initial compound for our study. For synthesis of hexyl, heptyl, octyl, nonyl, decyl and benzyl esters of 3-benzyl-8-propylxanthinyl-7-acetic acid we used alternative method, that included alkylation of sodium salts of acids with alkyl halogens. Reaction was made at DMF medium by reflux of reagents. Next stage of our research was the synthesis of amides of 3-beznyl-8-propylxanthinyl-7-acetic acid by the reaction of ethyl or propyl esters

Amino acid size, charge, hydropathy indices and matrices for protein structure analysis

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Biro JC

2006-03-01

Full Text Available Abstract Background Prediction of protein folding and specific interactions from only the sequence (ab initio is a major challenge in bioinformatics. It is believed that such prediction will prove possible if Anfinsen's thermodynamic principle is correct for all kinds of proteins, and all the information necessary to form a concrete 3D structure is indeed present in the sequence. Results We indexed the 200 possible amino acid pairs for their compatibility regarding the three major physicochemical properties – size, charge and hydrophobicity – and constructed Size, Charge and Hydropathy Compatibility Indices and Matrices (SCI & SCM, CCI & CCM, and HCI & HCM. Each index characterized the expected strength of interaction (compatibility of two amino acids by numbers from 1 (not compatible to 20 (highly compatible. We found statistically significant positive correlations between these indices and the propensity for amino acid co-locations in real protein structures (a sample containing total 34630 co-locations in 80 different protein structures: for HCI: p We tried to predict or reconstruct simple 2D representations of 3D structures from the sequence using these matrices by applying a dot plot-like method. The location and pattern of the most compatible subsequences was very similar or identical when the three fundamentally different matrices were used, which indicates the consistency of physicochemical compatibility. However, it was not sufficient to choose one preferred configuration between the many possible predicted options. Conclusion Indexing of amino acids for major physico-chemical properties is a powerful approach to understanding and assisting protein design. However, it is probably insufficient itself for complete ab initio structure prediction.

76 FR 81363 - Temperature-Indicating Devices; Thermally Processed Low-Acid Foods Packaged in Hermetically...

Science.gov (United States)

2011-12-28

... amended FDA's regulations for thermally processed low-acid foods packaged in hermetically sealed... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 113 [Docket No. FDA-2007-N-0265] (formerly 2007N-0026) Temperature-Indicating Devices; Thermally Processed Low-Acid...

Efficient Havinga–Kondepudi resolution of conglomerate amino acid derivatives by slow cooling and abrasive grinding

NARCIS (Netherlands)

Leeman, Michel; Noorduin, Wim L.; Millemaggi, Alessia; Vlieg, Elias; Meekes, Hugo; Enckevort, Willem J.P. van; Kaptein, Bernard; Kellogg, Richard M.

2010-01-01

The complete resolution of the conglomerate racemates of two amino acid derivatives susceptible to racemization in solution was achieved by slow crystallization from a supersaturated solution accompanied by cooling and abrasive grinding.

Five new prenylated p-hydroxybenzoic acid derivatives with antimicrobial and molluscicidal activity from Piper aduncum leaves.

Science.gov (United States)

Orjala, J; Erdelmeier, C A; Wright, A D; Rali, T; Sticher, O

1993-12-01

Five new prenylated benzoic acid derivatives, methyl 3-(3,7-dimethyl-2,6-octadienyl)-4-methoxybenzoate (1), 1-(1-methylethyl)-4-methyl-3-cyclohexenyl 3,5-bis(3-methyl-2-butenyl)-4-hydroxybenzoate (2), 1-(1-methylethyl)-4-methyl-3-cyclohexenyl 3,5-bis(3-methyl-2-butenyl)-4-methoxybenzoate (3), methyl 3,5-bis(3-methyl-2-butenyl)-4-methoxybenzoate (4), and 4-hydroxy-3-(3-methyl-2-butenyl)-5-(3-methyl-2-butenyl)-benzoic acid (5) were isolated from the dried leaves of Piper aduncum L. (Piperaceae). Together with the new metabolites, four known prenylated benzoic acid derivatives, 3,5-bis(3-methyl-2-butenyl)-4-methoxybenzoic acid (6), 4-hydroxy-3,5-bis(3-methyl-2-butenyl)-benzoic acid (nervogenic acid, 7), methyl 4-hydroxy-3,5-bis(3-methyl-2-butenyl)-benzoate (8), and methyl 4-hydroxy-3-(3-methyl-2-butenyl)-benzoate (9) as well as, dillapiol (10), myristicin, and the three sesquiterpenes humulene, caryophyllene epoxide, and humulene epoxide were isolated. Compounds 7, 8, and 9 are reported as natural products for the first time. The structures of the isolates were elucidated by spectroscopic methods, mainly 1D-and 2D-NMR spectroscopy. Isolates 4-7, 9, and 10 were molluscicidal while 2, 5-7, and 9 displayed significant antibacterial activities.

The dominant detritus-feeding invertebrate in Arctic peat soils derives its essential amino acids from gut symbionts

DEFF Research Database (Denmark)

Larsen, Thomas; Ventura, Marc; Maraldo, Kristine

2016-01-01

insufficiencies of macronutrients such as essential amino acids (EAA). Documenting whether gut symbionts also function as partners for symbiotic EAA supplementation is important because the question of how some detritivores are able to subsist on nutritionally insufficient diets has remained unresolved. 3....... To answer this poorly understood nutritional aspect of symbiont-host interactions, we studied the enchytraeid worm, a bulk soil feeder that thrives in Arctic peatlands. In a combined field and laboratory study, we employed stable isotope fingerprinting of amino acids to identify the biosynthetic origins...... of amino acids to bacteria, fungi and plants in enchytraeids. 4. Enchytraeids collected from Arctic peatlands derived more than 80% of their EAA from bacteria. In a controlled feeding study with the enchytraeid Enchytraeus crypticus, EAA derived almost exclusively from gut bacteria when the worms fed...

Metallic Langmuir and Langmuir-Blodgett films based on TTF derivatives and fatty acid

International Nuclear Information System (INIS)

Ohnuki, H.; Ishizaki, Y.; Suzuki, M.; Desbat, B.; Delhaes, P.; Giffard, M.; Imakubo, T.; Mabon, G.; Izumi, M.

2002-01-01

Recent progress in the metallic conducting Langmuir-Blodgett (LB) films built from TTF derivative and fatty acids is reported. A simple LB method of transferring the mixed Langmuir (L) film of BEDO-TTF (BO) and stearic acid (SA) onto substrates provided metallic conducting LB films. A homogeneous L film formation on the water surface observed by Brewster angle microscope (BAM) is an essential factor for the well-ordered LB films. In the L film, the carboxylate group of fatty acid forms anion layer bringing about a spontaneous formation of mixed valence state (MVS) of BO layer. Similar spontaneous formation was also found in the molecular combination of nonoxygen-substituted donor of EDT-TTF and octadecanesulfonic acid (OS). This type of reaction would be useful for obtaining conducting LB films. For the LB films of BEDO-TTF and stearic acid, we found a negative transverse magnetoresistance at low temperature that was interpreted in the weak localization of a two-dimensional (2D) electronic system based on the well-defined conducting layer

Antioxidant and DPPH (1,1-diphenyl-2-picrylhydrazyl Free Radical Scavenging Activities of Boniger Acid and Calix[4]arene Derivative

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E. ERDEM

2014-07-01

Full Text Available Diazonium derivative of calix[4]arene has been synthesized using three different synthetic steps. Initially p-tert-butylcalix[4]arene was synthesized with the condensation reaction of p-tert-butylphenol and formaldehyde in basic conditions. Calix[4]arene was obtained after the debutylation reaction of p-tert-butylcalix[4]arene with AlCl3. Calix[4]arene reacted with diazonium salt of Böniger acid to yield the 5,17-[(Bis(azo-bis(5-hydroxy-2,7-naphthalenedisulfonicacid]-25,26,27,28-tetrahydroxy calix[4]arene which has eight free phenolic hydroxyl group. Reaction steps were shown in Fig.1.2,7-naphthalenedisulfonicacid]-25,26,27,28-tetrahydroxy calix[4]arene The antioxidant activity of the Böniger acid and calix[4]aren derivative were determined using β-karotene-linoleic acid system. Moreover, the free radical scavenging activity values were tested with DPPH free radical. The two compounds showed strong antioxidant activity. Total antioxidant activity of Böniger acid and calix[4]aren derivative was determined using β–carotenelinoleic acid model system and was found the antioxidant activity of 84.00% and 85.60 % respectively. The free radical scavenging activities were determined as 83.05% and 84.69 %. Results show that, two compounds has the antioxidant activity. The calix[4]aren derivaties has more higher activity then Boniger acid because of calix[4]aren derivative has much hydroxl groups.

Gut microbiota–derived short-chain fatty acids and kidney diseases

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Li L

2017-12-01

Full Text Available Lingzhi Li, Liang Ma, Ping Fu Kidney Research Institute, Department of Nephrology, West China Hospital of Sichuan University, Chengdu 610041, China Abstract: Gut microbiota and its metabolites play pivotal roles in host physiology and pathology. Short-chain fatty acids (SCFAs, as a group of metabolites, exert positive regulatory effects on energy metabolism, hormone secretion, immune inflammation, hypertension, and cancer. The functions of SCFAs are related to their activation of transmembrane G protein-coupled receptors and their inhibition of histone acetylation. Though controversial, growing evidence suggests that SCFAs, which regulate inflammation, oxidative stress, and fibrosis, have been involved in kidney disease through the activation of the gut–kidney axis; however, the molecular relationship among gut microbiota–derived metabolites, signaling pathways, and kidney disease remains to be elucidated. This review will provide an overview of the physiology and functions of SCFAs in kidney disease. Keywords: gut microbiome, short-chain fatty acids, kidney diseases, gut–kidney axis

Hydroxamic acid derivatives as potent peptide deformylase inhibitors and antibacterial agents.

Science.gov (United States)

Apfel, C; Banner, D W; Bur, D; Dietz, M; Hirata, T; Hubschwerlen, C; Locher, H; Page, M G; Pirson, W; Rossé, G; Specklin, J L

2000-06-15

Low-molecular-weight beta-sulfonyl- and beta-sulfinylhydroxamic acid derivatives have been synthesized and found to be potent inhibitors of Escherichia coli peptide deformylase (PDF). Most of the compounds synthesized and tested displayed antibacterial activities that cover several pathogens found in respiratory tract infections, including Chlamydia pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. The potential of these compounds as antibacterial agents is discussed with respect to selectivity, intracellular concentrations in bacteria, and potential for resistance development.

Novel self-associative and multiphase nanostructured soft carriers based on amphiphilic hyaluronic acid derivatives

DEFF Research Database (Denmark)

Eenschooten, Corinne; Vaccaro, Andrea; Delie, Florence

2012-01-01

The purpose of the present study was to investigate the physicochemical properties in aqueous media of amphiphilic hyaluronic acid (HA) derivatives obtained by reaction of HA’s hydroxyl groups with octenyl succinic anhydride (OSA). The self-associative properties of the resulting octenyl succinic...

Phospholipid-derived fatty acids as chemotaxonomic markers for phytoplankton: application for inferring phytoplankton composition

NARCIS (Netherlands)

Dijkman, N.A.; Kromkamp, J.C.

2006-01-01

Phospholipid-derived fatty acids (PLFA) are widely used as chemotaxonomic markers in microbial ecology. In this paper we explore the use of PLFA as chemotaxonomic markers for phytoplankton species. The PLFA composition was determined for 23 species relevant to estuarine phytoplankton. The taxonomic

Diethylenetriaminepentaacetic acid-gadolinium (DTPA-Gd)-conjugated polysuccinimide derivatives as magnetic resonance imaging contrast agents.

Science.gov (United States)

Lee, Ha Young; Jee, Hye Won; Seo, Sung Mi; Kwak, Byung Kook; Khang, Gilson; Cho, Sun Hang

2006-01-01

Biocompatible polysuccinimide (PSI) derivatives conjugated with diethylenetriaminepentaacetic acid gadolinium (DTPA-Gd) were prepared as magnetic resonance imaging (MRI) contrast agents. In this study, we synthesized PSI derivatives incorporating methoxy-poly(ethylene glycol) (mPEG) as hydrophilic ligand, hexadecylamine as hydrophobic ligand, and DTPA-Gd as contrast agent. PSI was synthesized by the polycondensation polymerization of aspartic acid. All the synthesized materials were characterized by proton nuclear magnetic resonance (1H NMR). Critical micellization concentrations were determined using fluorescent probes (pyrene). Micelle size and shape were measured by electro-photometer light scattering (ELS) and atomic force microscopy (AFM). The formed micelle size ranged from 100 to 300 nm. The T1-weighted MR images of the phantom prepared with PSI-mPEG-C16-(DTPA-Gd) were obtained in a 3.0 T clinical MR imager, and the conjugates showed a great potential as MRI contrast agents.

[Soil carbohydrates: their determination methods and indication functions].

Science.gov (United States)

Zhang, Wei; Xie, Hongtu; He, Hongbo; Zheng, Lichen; Wang, Ge

2006-08-01

Soil carbohydrates are the important component of soil organic matter, and play an important role in soil aggregation formation. Their hydrolysis methods involve sulfur acid (H2SO4), hydrochloric acid (HCl), and trifluoroacetic acid (TFA) hydrolysis, and their determination methods include colorimetry, gas-liquid chromatography (GLC) , high performance liquid chromatography (HPLC), and high performance anion-exchange chromatography with pulsed amperometric detection (HPAE-PAD). This paper summarized the methods of carbohydrates' hydrolysis, purification and detection, with focus on the derived methods of GLC, and briefly introduced the indication functions of carbohydrates in soil organic matter turnover.

Benzaldehyde, 2-hydroxybenzoyl hydrazone derivatives as inhibitors of the corrosion of aluminium in hydrochloric acid.

Science.gov (United States)

Fouda, A S; Gouda, M M; El-Rahman, S I

2000-05-01

The effect of benzaldehyde, 2-hydroxybenzoyl hydrazone derivatives on the corrosion of aluminium in hydrochloric acid has been investigated using thermometric and polarization techniques. The inhibitive efficiency ranking of these compounds from both techniques was found to be: 2>3>1>4. The inhibitors acted as mixed-type inhibitors but the cathode is more polarized. The relative inhibitive efficiency of these compounds has been explained on the basis of structure of the inhibitors and their mode of interaction at the surface. Results show that these additives are adsorbed on an aluminium surface according to the Langmuir isotherm. Polarization measurements indicated that the rate of corrosion of aluminium rapidly increases with temperature over the range 30-55 degrees C both in the absence and in the presence of inhibitors. Some thermodynamic data of the adsorption process are calculated and discussed.

Synthesis and characterization of new chiral ketopinic acid-derived catalysts immobilized on polystyrene-bound imidazole

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Hassan Yusuf

2017-02-01

Full Text Available Four new chiral ketopinic acid-derived catalysts were anchored on a polystyrene-bound imidazole via non-covalent bond. The resulting heterogeneous catalysts were successfully characterized using IR, SEM, and TGA analyses.

Flavonols and ellagic acid derivatives in peels of different species of jabuticaba (Plinia spp.) identified by HPLC-DAD-ESI/MSn.

Science.gov (United States)

Neves, Nathália de Andrade; Stringheta, Paulo César; Gómez-Alonso, Sergio; Hermosín-Gutiérrez, Isidro

2018-06-30

Extracts of jabuticaba peels show complex chromatographic profiles at 360 nm, with some peaks presenting UV-Vis spectra resembling those of flavonol glycosides and others resembling that of ellagic acid. The presence and tentative identification of these phenolic compounds were comprehensively studied in four species of Brazilian jabuticaba fruit - Plinia trunciflora, variety 'jabuticaba de cabinho'; P. caulifora, varieties 'jabuticaba paulista' and 'jabuticaba canaã-açu'; P. jaboticaba, variety 'jabuticaba sabará'; and P. phitrantha, variety 'jabuticaba branca-vinho' - using HPLC-DAD-ESI-MS n . Seventeen flavonols derived from quercetin and three from myricetin and eighteen derivatives of ellagic acid and eleven of methyl ellagic acid were detected. Most of them were newly described and mainly occurred in glycosylated and acylglycosylated forms. Some compounds were missing in one variety, such as the absence of methyl ellagic acid derivatives in 'jabuticaba branca-vinho', and others only appeared in one variety, thus suggesting potential capacity for varietal differentiation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Correlating electronic structure with corrosion inhibition potentiality of some bis-benzimidazole derivatives for mild steel in hydrochloric acid: Combined experimental and theoretical studies

International Nuclear Information System (INIS)

Dutta, Alokdut; Saha, Sourav Kr.; Banerjee, Priyabrata; Sukul, Dipankar

2015-01-01

Highlights: • Bis-benzimidazole derivatives as good corrosion inhibitors for mild steel in acid. • Simultaneous both way electron-transfer is expected to occur during adsorption. • Role of molecular conformation on inhibition efficiency is demonstrated. • Good correlation between inhibition efficiency and molecular parameters established. • MD simulation results support experimental observations. - Abstract: Four different bis-benzimidazole (BBI) derivatives, tested as potential corrosion inhibitors for mild steel in 1 M HCl, have revealed good inhibition efficiency for long period of exposure. Inhibitors impart high resistance towards charge transfer across metal–electrolyte interface and behave broadly as mixed type. DFT calculations are used to correlate inhibition potentiality with intrinsic molecular parameters. From the optimized geometry of BBI derivatives, electron distribution in HOMO and LUMO and Fukui indices of each atom, possible modes of interaction of BBI derivatives with mild steel surface have been predicted. Energy corresponding to inhibitor-metal surface interaction is evaluated following molecular dynamics simulation

The effect of short-chain fatty acids on human monocyte-derived dendritic cells

DEFF Research Database (Denmark)

Nastasi, Claudia; Candela, Marco; Bonefeld, Charlotte Menné

2015-01-01

negligible effects, while both butyrate and propionate strongly modulated gene expression in both immature and mature human monocyte-derived DC. An Ingenuity pathway analysis based on the differentially expressed genes suggested that propionate and butyrate modulate leukocyte trafficking, as SCFA strongly......The gut microbiota is essential for human health and plays an important role in the pathogenesis of several diseases. Short-chain fatty acids (SCFA), such as acetate, butyrate and propionate, are end-products of microbial fermentation of macronutrients that distribute systemically via the blood....... The aim of this study was to investigate the transcriptional response of immature and LPS-matured human monocyte-derived DC to SCFA. Our data revealed distinct effects exerted by each individual SCFA on gene expression in human monocyte-derived DC, especially in the mature ones. Acetate only exerted...

Host-Derived Sialic Acids Are an Important Nutrient Source Required for Optimal Bacterial Fitness In Vivo

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Nathan D. McDonald

2016-04-01

Full Text Available A major challenge facing bacterial intestinal pathogens is competition for nutrient sources with the host microbiota. Vibrio cholerae is an intestinal pathogen that causes cholera, which affects millions each year; however, our knowledge of its nutritional requirements in the intestinal milieu is limited. In this study, we demonstrated that V. cholerae can grow efficiently on intestinal mucus and its component sialic acids and that a tripartite ATP-independent periplasmic SiaPQM strain, transporter-deficient mutant NC1777, was attenuated for colonization using a streptomycin-pretreated adult mouse model. In in vivo competition assays, NC1777 was significantly outcompeted for up to 3 days postinfection. NC1777 was also significantly outcompeted in in vitro competition assays in M9 minimal medium supplemented with intestinal mucus, indicating that sialic acid uptake is essential for fitness. Phylogenetic analyses demonstrated that the ability to utilize sialic acid was distributed among 452 bacterial species from eight phyla. The majority of species belonged to four phyla, Actinobacteria (members of Actinobacillus, Corynebacterium, Mycoplasma, and Streptomyces, Bacteroidetes (mainly Bacteroides, Capnocytophaga, and Prevotella, Firmicutes (members of Streptococcus, Staphylococcus, Clostridium, and Lactobacillus, and Proteobacteria (including Escherichia, Shigella, Salmonella, Citrobacter, Haemophilus, Klebsiella, Pasteurella, Photobacterium, Vibrio, and Yersinia species, mostly commensals and/or pathogens. Overall, our data demonstrate that the ability to take up host-derived sugars and sialic acid specifically allows V. cholerae a competitive advantage in intestinal colonization and that this is a trait that is sporadic in its occurrence and phylogenetic distribution and ancestral in some genera but horizontally acquired in others.

Synthesis and Pharmacological Screening of Several Aroyl and Heteroaroyl Selenylacetic Acid Derivatives as Cytotoxic and Antiproliferative Agents

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Carmen Sanmartín

2009-09-01

Full Text Available The synthesis and cytotoxic activity of a series of twenty six aroyl and heteroaroyl selenylacetic acid derivatives of general formula Ar-CO-Se-CH2-COOH or Heterar-CO-Se-CH2-COOH are reported. The synthesis was carried out by reaction of acyl chlorides with sodium hydrogen selenide, prepared in situ, and this led to the formation of sodium aroylselenides that subsequently reacted with α-bromoacetic acid to produce the corresponding selenylacetic acid derivatives. All of the compounds were tested against a prostate cancer cell line (PC-3 and some of the more active compounds were assessed against a panel of four human cancer cell lines (CCRF-CEM, HTB-54, HT-29, MCF-7 and one mammary gland-derived non-malignant cell line (184B5. Some of the compounds exhibited remarkable cytotoxic and antiproliferative activities against MCF-7 and PC-3 that were higher than those of the reference compounds doxorubicin and etoposide, respectively. For example, in MCF-7 when Ar = phenyl, 3,5-dimethoxyphenyl or benzyl the TGI values were 3.69, 4.18 and 6.19 μM. On the other hand, in PC-3 these compounds showed values of 6.8, 4.0 and 2.9 μM. Furthermore, benzoylselenylacetic acid did not provoke apoptosis nor did it perturb the cell cycle in MCF-7.

Design and preparation of derivatives of oleanolic and glycyrrhetinic acids with cytotoxic properties

Directory of Open Access Journals (Sweden)

Wang R

2018-05-01

Full Text Available Rui Wang,1,* Yang Li,2,* Xu-Dong Huai,3 Qing-Xuan Zheng,1 Wei Wang,1 Hui-Jing Li,4 Qi-Yong Huai1 1Marine College, Shandong University, Weihai, China; 2Zhong Yuan Academy of Biological Medicine, Liaocheng People’s Hospital/Affiliated Liaocheng Hospital, Taishan Medical University, Liaocheng, China; 3School of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, China; 4School of Marine Science and Technology, Harbin Institute of Technology at Weihai, Weihai, China *These authors contributed equally to this work Background: The structural modification of natural products with the aim to improve the anticancer activity is a popular current research direction. The pentacyclic triterpenoid compounds oleanolic acid (OA and glycyrrhetinic acid (GA are distributed widely in nature. Methods: In this study, various oleanolic acids and glycyrrhetinic acids were designed and synthesized by using the combination principle. The in vitro anticancer activities of new OA and GA derivatives were tested by the 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT method with SGC-7901 (gastric cancer, MCF-7 (breast cancer, Eca-109 (esophageal cancer, HeLa (cervical cancer, Hep-G2 (hepatoma cancer and HSF (normal human skin fibroblast cells. Results and conclusion: The screening results showed that the compound 3m presented the highest inhibitory activities against SGC-7901, MCF-7 and Eca-109 cell lines with IC50 values of 7.57±0.64 µM, 5.51±0.41 µM and 5.03±0.56 µM, respectively. In addition, this compound also showed effective inhibition of Hep-G2 cells with an IC50 value of 4.11±0.73 µM. Moreover, compound 5b showed the strongest inhibitory activity against Hep-G2 cells with an IC50 value of 3.74±0.18 µM and compound 3l showed strong selective inhibition of the HeLa cells with the lowest IC50 value of 4.32±0.89 µM. A series of pharmacology experiments indicated that compound 5b could induce Hep-G2

Establishment of Hairy Root Cultures of Rhaponticum carthamoides (Willd. Iljin for the Production of Biomass and Caffeic Acid Derivatives

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Ewa Skała

2015-01-01

Full Text Available The aim of the study was to obtain transformed roots of Rhaponticum carthamoides and evaluate their phytochemical profile. Hairy roots were induced from leaf explants by the transformation of Agrobacterium rhizogenes strains A4 and ATCC 15834. The best response (43% was achieved by infection with A4 strain. The effects of different liquid media (WPM, B5, SH with full and half-strength concentrations of macro- and micronutrients on biomass accumulation of the best grown hairy root line (RC3 at two different lighting conditions (light or dark were investigated. The highest biomass (93 g L−1 of the fresh weight after 35 days was obtained in WPM medium under periodic light. UPLC-PDA-ESI-MS3 and HPLC-PDA analyses of 80% aqueous methanol extracts from the obtained hairy roots revealed the presence of eleven caffeoylquinic acids and their derivatives and five flavonoid glycosides. The production of caffeoylquinic acids and their derivatives was elevated in hairy roots grown in the light. Only light-grown hairy roots demonstrated the capability for the biosynthesis of such flavonoid glycosides as quercetagetin, quercetin, luteolin, and patuletin hexosides. Chlorogenic acid, 3,5-di-O-caffeoylquinic acid and a tentatively identified tricaffeoylquinic acid derivative were detected as the major compounds present in the transformed roots.

Vibrational spectroscopic study of dehydroacetic acid and its cinnamoyl pyrone derivatives

Science.gov (United States)

Billes, Ferenc; Elečková, Lenka; Mikosch, Hans; Andruch, Vasil

2015-07-01

The infrared and Raman spectra of dehydroacetic acid and some of its derivatives were measured. The assignments of the vibrational bands were based on quantum chemical calculations and normal coordinate analysis. The optimized structures, atomic net charges and dipole moments of the investigated molecules were also results of our quantum chemical calculations. The analysis of the last properties made possible a deeper insight into the structure and substituent effect on the investigated molecules. One of them is presented in the graphical abstract.

Structure, Content, and Bioactivity of Food-Derived Peptides in the Body.

Science.gov (United States)

Sato, Kenji

2018-03-28

Orally administered peptides are assumed to be degraded into amino acids in the body. However, our recent studies revealed some food-derived prolyl and pyroglutamyl peptides with 2-3 amino acid residues in the blood of humans and animals, while most of the peptides in the endoproteinase digest of food protein are degraded by exopeptidase. Some food-derived dipeptides in the body display in vitro and in vivo biological activities. These facts indicate that the biological activities of food-derived peptides in the body rather than those in food are crucial to understanding the mechanism of the beneficial effects of orally administered peptides.

Physico-chemical characterization of mixed-ligand complexes of Mn(III based on the acetylacetonate and maleic acid and its hydroxylamine derivative

Directory of Open Access Journals (Sweden)

Cakić Suzana M.

2005-01-01

Full Text Available Two new Mn(III mixed-ligand complexes with two acetylacetonate (acac ligands and one maleate ligand and its hydroxylamine derivative of the general formula [Mn(C5H7O22L] were prepared. Their structure was established by using elemental analysis, FTIR and UV/VIS spectroscopic methods, as well as magnetic measurement. Replacement of the acetylacetonate ligand by the corresponding acid ligand has been confirmed in Mn(III acetylacetonate. Based on the obtained experimental data and literature indications, structural formulae to these compounds were assigned.

The comparison of knee osteoarthritis treatment with single-dose bone marrow-derived mononuclear cells vs. hyaluronic acid injections.

Science.gov (United States)

Goncars, Valdis; Jakobsons, Eriks; Blums, Kristaps; Briede, Ieva; Patetko, Liene; Erglis, Kristaps; Erglis, Martins; Kalnberzs, Konstantins; Muiznieks, Indrikis; Erglis, Andrejs

2017-01-01

The aim of this study was to compare treatment methods of the knee joint degenerative osteoarthritis, using autologous bone marrow-derived mononuclear cells and hyaluronic acid injections and observe prevalence of adverse effects in both groups. A prospective randomized controlled clinical trial was carried out. The analysis of pain and changes in osteoarthritis symptoms after a single intra-articular bone marrow-derived mononuclear cell injection into the knee joint in the Kellgren-Lawrence stage II-III osteoarthritis during the 12-month period were performed. The results were compared with the control group treated routinely by hyaluronic acid injections therapy. A therapy group of patients (n=28) received single bone marrow-derived mononuclear cell intra-articular injections. A control group of patients (n=28) was treated with a total of three sodium hyaluronate intra-articular injections each one performed a week apart. The clinical results were obtained using the Knee Osteoarthritis Outcome Score (KOOS) and the Knee Society Score (KSS) before and 3, 6, and 12 months after injection. A statistically significant improvement was observed in the mononuclear cell group over the starting point in all scores. At the endpoint at month 12, the KOOS score improved significantly (Phyaluronic acid versus the bone marrow-derived mononuclear cells group at time points 6 and 12 months demonstrated a statistically significant (Phyaluronic acid group. In both groups serious adverse effects were not observed. The intra-articular injection of bone marrow-derived mononuclear cells is a safe manipulation with no side effects during the 12-month period. This treatment provides statistically significant clinical improvement between the starting point and 1, 3, 6, and 12 months after. When compared to hyaluronic acid treatment, better pain relief in the long-term period of mononuclear cell group was observed. Copyright © 2017 The Lithuanian University of Health Sciences. Production

Revisiting the chemical reactivity indices as the state function derivatives. The role of classical chemical hardness

Energy Technology Data Exchange (ETDEWEB)

Malek, Ali; Balawender, Robert, E-mail: rbalawender@ichf.edu.pl [Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, PL-01-224 Warsaw (Poland)

2015-02-07

The chemical reactivity indices as the equilibrium state-function derivatives are revisited. They are obtained in terms of the central moments (fluctuation formulas). To analyze the role of the chemical hardness introduced by Pearson [J. Am. Chem. Soc. 105, 7512 (1983)], the relations between the derivatives up to the third-order and the central moments are obtained. As shown, the chemical hardness and the chemical potential are really the principal indices of the chemical reactivity theory. It is clear from the results presented here that the chemical hardness is not the derivative of the Mulliken chemical potential (this means also not the second derivative of the energy at zero-temperature limit). The conventional quadratic dependence of energy, observed at finite temperature, reduces to linear dependence on the electron number at zero-temperature limit. The chemical hardness plays a double role in the admixture of ionic states to the reference neutral state energy: it determines the amplitude of the admixture and regulates the damping of its thermal factor.

Revisiting the chemical reactivity indices as the state function derivatives. The role of classical chemical hardness

International Nuclear Information System (INIS)

Malek, Ali; Balawender, Robert

2015-01-01

The chemical reactivity indices as the equilibrium state-function derivatives are revisited. They are obtained in terms of the central moments (fluctuation formulas). To analyze the role of the chemical hardness introduced by Pearson [J. Am. Chem. Soc. 105, 7512 (1983)], the relations between the derivatives up to the third-order and the central moments are obtained. As shown, the chemical hardness and the chemical potential are really the principal indices of the chemical reactivity theory. It is clear from the results presented here that the chemical hardness is not the derivative of the Mulliken chemical potential (this means also not the second derivative of the energy at zero-temperature limit). The conventional quadratic dependence of energy, observed at finite temperature, reduces to linear dependence on the electron number at zero-temperature limit. The chemical hardness plays a double role in the admixture of ionic states to the reference neutral state energy: it determines the amplitude of the admixture and regulates the damping of its thermal factor

Incorporation of oxygen into abscisic acid and phaseic acid for molecular oxygen

International Nuclear Information System (INIS)

Creelman, R.A.; Zeevaart, J.A.D.

1984-01-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumariu. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% 18 O 2 and 80% N 2 indicates that one atom of 18 O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase. Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing 18 O 2 indicates that one atom of 18 O is presented in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-streesed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggest that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress. 17 references, 2 figures, 1 tables

Incorporation of oxygen into abscisic Acid and phaseic Acid from molecular oxygen.

Science.gov (United States)

Creelman, R A; Zeevaart, J A

1984-05-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% (18)O(2) and 80% N(2) indicates that one atom of (18)O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase.Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing (18)O(2) indicates that one atom of (18)O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress.

Safety evaluation of pectin-derived acidic oligosaccharides (pAOS): genotoxicity and sub-chronic studies.

NARCIS (Netherlands)

Garthoff, J.A.; Heemskerk, S.; Hempenius, R.A.; Lina, B.A.; Krul, C.A.; Koeman, J.H.; Speijers, G.J.

2010-01-01

Pectin-derived acidic oligosaccharides (pAOS) are non-digestible carbohydrates to be used in infant formulae and medical nutrition. To support its safety, the genotoxic potential of pAOS was evaluated. pAOS was not mutagenic in the Ames test. Positive results were obtained in the chromosome

Safety evaluation of pectin-derived acidic oligosaccharides (pAOS): Genotoxicity and sub-chronic studies

NARCIS (Netherlands)

Garthoff, J.A.; Heemskerk, S.; Hempenius, R.A.; Lina, B.A.R.; Krul, C.A.M.; Koeman, J.H.; Speijers, G.J.A.

2010-01-01

Pectin-derived acidic oligosaccharides (pAOS) are non-digestible carbohydrates to be used in infant formulae and medical nutrition. To support its safety, the genotoxic potential of pAOS was evaluated. pAOS was not mutagenic in the Ames test. Positive results were obtained in the chromosome

Growth behavior of anodic oxide formed by aluminum anodizing in glutaric and its derivative acid electrolytes

Science.gov (United States)

Nakajima, Daiki; Kikuchi, Tatsuya; Natsui, Shungo; Suzuki, Ryosuke O.

2014-12-01

The growth behavior of anodic oxide films formed via anodizing in glutaric and its derivative acid solutions was investigated based on the acid dissociation constants of electrolytes. High-purity aluminum foils were anodized in glutaric, ketoglutaric, and acetonedicarboxylic acid solutions under various electrochemical conditions. A thin barrier anodic oxide film grew uniformly on the aluminum substrate by glutaric acid anodizing, and further anodizing caused the film to breakdown due to a high electric field. In contrast, an anodic porous alumina film with a submicrometer-scale cell diameter was successfully formed by ketoglutaric acid anodizing at 293 K. However, the increase and decrease in the temperature of the ketoglutaric acid resulted in non-uniform oxide growth and localized pitting corrosion of the aluminum substrate. An anodic porous alumina film could also be fabricated by acetonedicarboxylic acid anodizing due to the relatively low dissociation constants associated with the acid. Acid dissociation constants are an important factor for the fabrication of anodic porous alumina films.

Anti-Inflammatory Effects of Cajaninstilbene Acid and Its Derivatives.

Science.gov (United States)

Huang, Mei-Yan; Lin, Jing; Lu, Kuo; Xu, Hong-Gui; Geng, Zhi-Zhong; Sun, Ping-Hua; Chen, Wei-Min

2016-04-13

Cajaninstilbene acid (CSA) is one of the active components isolated from pigeon pea leaves. In this study, anti-inflammatory effects of CSA and its synthesized derivatives were fully valued with regard to their activities on the production of nitric oxide (NO) and pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in vitro cell model, as well as their impacts on the migration of neutrophils and macrophages in fluorescent protein labeled zebrafish larvae model by live image analysis. Furthermore, the anti-inflammatory mechanism of this type of compounds was clarified by western-blot and reverse transcription-polymerase chain reaction (RT-PCR). The results showed that CSA, as well as its synthesized derivatives 5c, 5e and 5h, exhibited strong inhibition activity on the release of NO and inflammatory factor TNF-α and IL-6 in lipopolysaccharides (LPS)-stimulated murine macrophages. CSA and 5c greatly inhibited the migration of neutrophils and macrophages in injury zebrafish larvae. CSA and 5c treatment greatly inhibited the phosphorylation of proteins involved in nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. Moreover, we found that peroxisome proliferator-activated receptor gamma (PPARγ) inhibitor GW9662 could reverse partly the roles of CSA and 5c, and CSA and 5c treatment greatly resist the decrease of PPARγ mRNA and protein induced by LPS stimulation. Our results identified the promising anti-inflammatory effects of CSA and its derivatives, which may serve as valuable anti-inflammatory lead compound. Additionally, the mechanism studies demonstrated that the anti-inflammatory activity of CSA and its derivative is associated with the inhibition of NF-κB and MAPK pathways, relying partly on resisting the LPS-induced decrease of PPARγ through improving its expression.

Modified method for zirconium or hafnium gravimetric determination with glycolic acid derivatives

International Nuclear Information System (INIS)

Barbieri, R.S.; Rocha, J.C.; Terra, V.R.; Marques Neto, A.

1989-01-01

The conditions for gravimetric determination of zirconium or hafnium by glicolic acid derivatives were studied by thermogravimetric analysis. The method utilized shown that after precipitation, washing and drying of precipitates at 150 0 C, the resulting solid was weighed in the form of [M{RCH(OH)COO} 4 ] (M = Zr,Hf;R = C 6 H 5 , β-C 10 H 7 ,p-BrC 6 H 4 ). (author) [pt

Highly efficient production of D-lactic acid from chicory-derived inulin by Lactobacillus bulgaricus.

Science.gov (United States)

Xu, Qianqian; Zang, Ying; Zhou, Jie; Liu, Peng; Li, Xin; Yong, Qiang; Ouyang, Jia

2016-11-01

Inulin is a readily available feedstock for cost-effective production of biochemicals. To date, several studies have explored the production of bioethanol, high-fructose syrup and fructooligosaccharide, but there are no studies regarding the production of D-lactic acid using inulin as a carbon source. In the present study, chicory-derived inulin was used for D-lactic acid biosynthesis by Lactobacillus bulgaricus CGMCC 1.6970. Compared with separate hydrolysis and fermentation processes, simultaneous saccharification and fermentation (SSF) has demonstrated the best performance of D-lactic acid production. Because it prevents fructose inhibition and promotes the complete hydrolysis of inulin, the highest D-lactic acid concentration (123.6 ± 0.9 g/L) with a yield of 97.9 % was obtained from 120 g/L inulin by SSF. Moreover, SSF by L. bulgaricus CGMCC 1.6970 offered another distinct advantage with respect to the higher optical purity of D-lactic acid (>99.9 %) and reduced number of residual sugars. The excellent performance of D-lactic acid production from inulin by SSF represents a high-yield method for D-lactic acid production from non-food grains.

Acid-base indicator properties of dyes from local plants I: Dyes from ...

African Journals Online (AJOL)

DR. MIKE HORSFALL

Acid-base indicator properties of dyes from local plants I: Dyes from Basella alba. (Indian spinach) and ... solution, which change colour immediately after the equivalence point has .... The pH ranges over which the dyes change colour were ...

Synthesis and physical-chemical properties of 3-benzyl-8-propylxanthinyl-7-acetic acid and its derivatives

Directory of Open Access Journals (Sweden)

E. K. Mikhalchenko

2017-04-01

Full Text Available Introduction. Heterocyclic compounds play an important role in the metabolic processes of human organism. Structures of vitamins, nucleotides, chromoproteins are based on Nitrogen-containing heterocycles (purine, pyrimidine, thiazole etc. Thus, it was obvious to use these organic substances as basic molecules for synthetic research of biologically active compounds which could be used for treatment of different pathological processes. In their research, some scientist pay special attention to xanthine derivatives that are well-known low toxic natural compounds with wide spectrum of pronounced pharmacological properties (antioxidant, diuretic, antibacterial, anti-inflammatory etc. Insertion of carboxyl group in the structure of xanthine molecule is a prospective ability of its synthetic potential increasing. Aim of our research was the development of method of 3-benzyl-8-propylxanthinyl-7-acetic acid and its derivatives synthesis and studying their physical-chemical properties. Materials and methods. Melting points were determined using capillary method on DMP (M. 1Н NMR-spectra were recorded by Varian Mercury VX-200 device (company «Varian», USA solvent – (DMSO-d6, internal standard – ТМS. Elemental analysis of obtained compounds was produced on device Elementar Vario L cube. Results and discussion. We selected 3-benzyl-8-propyl xanthine as initial compound for our study. By its interaction with chloroacetic acid, chloroacetamide or propyl chloroacetate in DMF in the presence of calculated amount of NaHCO3 we synthesized 3-benzyl-8-propylxanthinyl-7-acetic acid its ester and amide. At the same time we found that obtaining of xanthinyl-7-acetic acid by hydrolysis of its ester produced with higher yield. On the next stage of our research we synthesized a number of water-soluble salts of 3-benzyl-8-propylxanthinyl-7-acetic acid by reaction of acid with different primary and secondary amines. The structures of all obtained compounds were

Brittle and ductile adjustable cement derived from calcium phosphate cement/polyacrylic acid composites.

Science.gov (United States)

Chen, Wen-Cheng; Ju, Chien-Ping; Wang, Jen-Chyan; Hung, Chun-Cheng; Chern Lin, Jiin-Huey

2008-12-01

Bone filler has been used over the years in dental and biomedical applications. The present work is to characterize a non-dispersive, fast setting, modulus adjustable, high bioresorbable composite bone cement derived from calcium phosphate-based cement combined with polymer and binding agents. This cement, we hope, will not swell in simulated body fluid and keep the osteogenetic properties of the dry bone and avoid its disadvantages of being brittle. We developed a calcium phosphate cement (CPC) of tetracalcium phosphate/dicalcium phosphate anhydrous (TTCP/DCPA)-polyacrylic acid with tartaric acid, calcium fluoride additives and phosphate hardening solution. The results show that while composite, the hard-brittle properties of 25wt% polyacrylic acid are proportional to CPC and mixing with additives is the same as those of the CPC without polyacrylic acid added. With an increase of polyacrylic acid/CPC ratio, the 67wt% samples revealed ductile-tough properties and 100wt% samples kept ductile or elastic properties after 24h of immersion. The modulus range of this development was from 200 to 2600MPa after getting immersed in simulated body fluid for 24h. The TTCP/DCPA-polyacrylic acid based CPC demonstrates adjustable brittle/ductile strength during setting and after immersion, and the final reaction products consist of high bioresorbable monetite/brushite/calcium fluoride composite with polyacrylic acid.

Palladium-Catalyzed Decarboxylative γ-Olefination of 2,5-Cyclohexadiene-1-carboxylic Acid Derivatives with Vinyl Halides.

Science.gov (United States)

Chang, Chi-Hao; Chou, Chih-Ming

2018-04-06

This study explores a Pd-catalyzed decarboxylative Heck-type Csp 3 -Csp 2 coupling reaction of 2,5-cyclohexadiene-1-carboxylic acid derivatives with vinyl halides to provide γ-olefination products. The olefinated 1,3-cyclohexadienes can be further oxidized to produce meta-alkylated stilbene derivatives. Additionally, the conjugated diene products can also undergo a Diels-Alder reaction to produce a bicyclo[2.2.2]octadiene framework.

Fast repair of oxidizing OH adducts of DNA by hydroxycinnamic acid derivatives. A pulse radiolytic study

International Nuclear Information System (INIS)

Yue Jiang; Lin Weizhen; Yao Side; Lin Nianyun; Zhu Dayuan

1999-01-01

Using pulse radiolytic techniques, it has been demonstrated that the interactions of oxidizing OH adducts of DNA (ssDNA and dsDNA), polyA and polyG with hydroxycinnamic acid derivatives proceed via an electron transfer process (k=5-30x10 8 dm 3 mol -1 s -1 ). In addition, the rates for fast repair of OH adducts of dAMP, polyA and DNA (ssDNA and dsDNA) are slower than the corresponding rates for the rest OH adducts of DNA constituents. The slower rates for repair of oxidizing OH adducts of dAMP may be the rate determining step during the interaction of hydroxycinnamic acid derivatives with OH adducts of DNA containing the varieties of OH adducts of DNA constituents

Facile synthesis of palladium nanoparticles supported on multi-walled carbon nanotube for efficient hydrogenation of biomass-derived levulinic acid

Energy Technology Data Exchange (ETDEWEB)

Yan, Kai, E-mail: kyan@lakeheadu.ca; Lafleur, Todd [Lakehead University, Department of Chemistry (Canada); Liao, Jiayou [Tianjin University, School of Chemical Engineering and Technology (China)

2013-09-15

Different loading of palladium (Pd) nanoparticles were successfully fabricated on multi-walled carbon nanotubes using Pd acetylacetonate as the precursor via a simple liquid impregnation method. The crystal phase, morphology, textural structure and the chemical state of the resulting Pd nanoparticles (Pd/CNT) catalysts were studied and the characterization results indicated that the uniform dispersion of small Pd nanoparticles with the size range of 1.0-4.5 nm was achieved. The synthesized Pd/CNT catalysts exhibited efficient performance for the catalytic hydrogenation of biomass-derived levulinic acid into biofuel {gamma}-valerolactone. In comparison with the commercial 5 wt% Pd/C and the 5 wt% Pd/CNT catalyst prepared by Pd nitrate precursor, much higher activities were achieved, whereas the biofuel {gamma}-valerolactone was highly produced with 56.3 % yield at 57.6 % conversion of levulinic acid on the 5 wt% Pd/CNT catalyst under mild conditions. The catalyst developed in this work may be a good candidate for the wide applications in the hydrogenation.

The oxanorbornene approach to 3-hydroxy, 3,4-dihydroxy and 3,4,5-trihydroxy derivatives of 2-aminocyclohexanecarboxylic acid

Directory of Open Access Journals (Sweden)

Howard Judith AK

2006-05-01

Full Text Available Abstract The nitro oxanorbornene adduct derived from the Diels-Alder reaction of ethyl (E-3-nitroacrylate and furan provides a versatile template for the stereoselective synthesis of hydroxylated derivatives of 2-aminocyclohexanecarboxylic acid (ACHC.

New derivatives of 3,4-dihydroisoquinoline-3-carboxylic acid with free-radical scavenging, D-amino acid oxidase, acetylcholinesterase and butyrylcholinesterase inhibitory activity.

Science.gov (United States)

Solecka, Jolanta; Guśpiel, Adam; Postek, Magdalena; Ziemska, Joanna; Kawęcki, Robert; Lęczycka, Katarzyna; Osior, Agnieszka; Pietrzak, Bartłomiej; Pypowski, Krzysztof; Wyrzykowska, Agata

2014-09-30

A series of 3,4-dihydroisoquinoline-3-carboxylic acid derivatives were synthesised and tested for their free-radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS·+), superoxide anion radical (O2·-) and nitric oxide radical (·NO) assays. We also studied d-amino acid oxidase (DAAO), acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activity. Almost each of newly synthesised compounds exhibited radical scavenging capabilities. Moreover, several compounds showed moderate inhibitory activities against DAAO, AChE and BuChE. Compounds with significant free-radical scavenging activity may be potential candidates for therapeutics used in oxidative-stress-related diseases.

Value-added potential of expeller-pressed canola oil refining: characterization of sinapic acid derivatives and tocopherols from byproducts.

Science.gov (United States)

Chen, Yougui; Thiyam-Hollander, Usha; Barthet, Veronique J; Aachary, Ayyappan A

2014-10-08

Valuable phenolic antioxidants are lost during oil refining, but evaluation of their occurrence in refining byproducts is lacking. Rapeseed and canola oil are both rich sources of sinapic acid derivatives and tocopherols. The retention and loss of sinapic acid derivatives and tocopherols in commercially produced expeller-pressed canola oils subjected to various refining steps and the respective byproducts were investigated. Loss of canolol (3) and tocopherols were observed during bleaching (84.9%) and deodorization (37.6%), respectively. Sinapic acid (2) (42.9 μg/g), sinapine (1) (199 μg/g), and canolol (344 μg/g) were found in the refining byproducts, namely, soap stock, spent bleaching clay, and wash water, for the first time. Tocopherols (3.75 mg/g) and other nonidentified phenolic compounds (2.7 mg sinapic acid equivalent/g) were found in deodistillates, a byproduct of deodorization. DPPH radical scavenging confirmed the antioxidant potential of the byproducts. This study confirms the value-added potential of byproducts of refining as sources of endogenous phenolics.

Effect of Vermicompost Extract and Vermicompost-Derived Humic Acids on Seed Germination and Seedling Growth of Hemp

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Ievinsh Gederts

2017-08-01

Full Text Available Hemp (Cannabis sativa L. cultivars grown for industrial use have recently emerged as a sustainable alternative source of industrial fibre and bioenergy, and is a highly valuable food and animal feed resource. The aim of the present study was to evaluate the effect of vermicompost extract, vermicompost mineral nutrient composition, and vermicompost-derived humic and fulvic acids on seed germination and growth of hemp seedlings. In general, separate application of all vermicompost components stimulated seed germination and hypocotyl and radicle growth, as well as increased chlorophyll concentration in cotyledons. Effective concentration range and the degree of stimulation varied significantly between the treatments. For practical purposes, application of vermicompost and vermicompost-derived extracts for stimulation of hemp growth could be useful at concentrations 5%, 0.05 mg·mL−1 and 1%, for vermicompost extract, humic acids and fulvic acids, respectively.

Protective effect of bile acid derivatives in phalloidin-induced rat liver toxicity

International Nuclear Information System (INIS)

Herraez, Elisa; Macias, Rocio I.R.; Vazquez-Tato, Jose; Hierro, Carlos; Monte, Maria J.; Marin, Jose J.G.

2009-01-01

Phalloidin causes severe liver damage characterized by marked cholestasis, which is due in part to irreversible polymerization of actin filaments. Liver uptake of this toxin through the transporter OATP1B1 is inhibited by the bile acid derivative BALU-1, which does not inhibit the sodium-dependent bile acid transporter NTCP. The aim of the present study was to investigate whether BALU-1 prevents liver uptake of phalloidin without impairing endogenous bile acid handling and hence may have protective effects against the hepatotoxicity induced by this toxin. In anaesthetized rats, i.v. administration of BALU-1 increased bile flow more than taurocholic acid (TCA). Phalloidin administration decreased basal (- 60%) and TCA-stimulated bile flow (- 55%) without impairing bile acid output. Phalloidin-induced cholestasis was accompanied by liver necrosis, nephrotoxicity and haematuria. In BALU-1-treated animals, phalloidin-induced cholestasis was partially prevented. Moreover haematuria was not observed, which was consistent with histological evidences of BALU-1-prevented injury of liver and kidney tissue. HPLC-MS/MS analysis revealed that BALU-1 was secreted in bile mainly in non-conjugated form, although a small proportion ( TCA > DHCA > UDCA. In conclusion, BALU-1 is able to protect against phalloidin-induced hepatotoxicity, probably due to an inhibition of the liver uptake and an enhanced biliary secretion of this toxin.

Molecular interaction of acetylcholinesterase with carnosic acid derivatives: a neuroinformatics study.

Science.gov (United States)

Merad, M; Soufi, W; Ghalem, S; Boukli, F; Baig, M H; Ahmad, K; Kamal, Mohammad A

2014-04-01

Alzheimer's disease is a progressive degenerative disease of the brain marked by gradual and irreversible declines in cognitive functions. Acetylcholinesterase (AChE) plays a biological role in the termination of nerve impulse transmissions at cholinergic synapses by rapid hydrolysis of its substrate, "acetylcholine". The deficit level of acetylcholine leads to deprived nerve impulse transmission. Thus the cholinesterase inhibitors would reverse the deficit in acetylcholine level and consequently may reverse the memory impairments, which is characteristic of the Alzheimer's disease. The molecular interactions between AChE and Carnosic acid, a well known antioxidant substance found in the leaves of the rosemary plant has always been an area of interest. Here in this study we have performed in silico approach to identify carnosic acid derivatives having the potential of being a possible drug candidate against AChE. The best candidates were selected on the basis of the results of different scoring functions.

How to eliminate the formation of chlorogenic acids artefacts during plants analysis? Sea sand disruption method (SSDM) in the HPLC analysis of chlorogenic acids and their native derivatives in plants.

Science.gov (United States)

Wianowska, Dorota; Typek, Rafał; Dawidowicz, Andrzej L

2015-09-01

The analytical procedures for determining plant constituents involve the application of sample preparation methods to fully isolate and/or pre-concentrate the analyzed substances. High-temperature liquid extraction is still applied most frequently for this purpose. The present paper shows that high-temperature extraction cannot be applied for the analysis of chlorogenic acids (CQAs) and their derivatives in plants as it causes the CQAs transformation leading to erroneous quantitative estimations of these compounds. Experiments performed on different plants (black elder, hawthorn, nettle, yerba maté, St John's wort and green coffee) demonstrate that the most appropriate method for the estimation of CQAs/CQAs derivatives is sea sand disruption method (SSDM) because it does not induce any transformation and/or degradation processes in the analyzed substances. Owing to the SSDM method application we found that the investigated plants, besides four main CQAs, contain sixteen CQAs derivatives, among them three quinic acids. The application of SSDM in plant analysis not only allows to establish a true concentration of individual CQAs in the examined plants but also to determine which chlorogenic acids derivatives are native plant components and what is their concentration level. What is even more important, the application of SSDM in plant analysis allows to eliminate errors that may arise or might have arisen in the study of chlorogenic acids and their derivatives in plant metabolism. Copyright © 2015 Elsevier Ltd. All rights reserved.

Silica Sulfuric Acid: An Eco-Friendly and Reusable Catalyst for Synthesis of Benzimidazole Derivatives

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Bahareh Sadeghi

2013-01-01

Full Text Available Silica sulfuric acid (SiO2-OSO3H as an eco-friendly, readily available, and reusable catalyst is applied to benzimidazole derivatives synthesis under reflux in ethanol. The procedure is very simple and the products are isolated with an easy workup in good-to-excellent yields.

Amino derivatives of glycyrrhetinic acid as potential inhibitors of cholinesterases.

Science.gov (United States)

Schwarz, Stefan; Lucas, Susana Dias; Sommerwerk, Sven; Csuk, René

2014-07-01

The development of remedies against the Alzheimer's disease (AD) is one of the biggest challenges in medicinal chemistry nowadays. Although not completely understood, there are several strategies fighting this disease or at least bringing some relief. During the progress of AD, the level of acetylcholine (ACh) decreases; hence, a therapy using inhibitors should be of some benefit to the patients. Drugs presently used for the treatment of AD inhibit the two ACh controlling enzymes, acetylcholinesterase as well as butyrylcholinesterase; hence, the design of selective inhibitors is called for. Glycyrrhetinic acid seems to be an interesting starting point for the development of selective inhibitors. Although its glycon, glycyrrhetinic acid is known for being an AChE activator, several derivatives, altered in position C-3 and C-30, exhibited remarkable inhibition constants in micro-molar range. Furthermore, five representative compounds were subjected to three more enzyme assays (on carbonic anhydrase II, papain and the lipase from Candida antarctica) to gain information about the selectivity of the compounds in comparison to other enzymes. In addition, photometric sulforhodamine B assays using murine embryonic fibroblasts (NiH 3T3) were performed to study the cytotoxicity of these compounds. Two derivatives, bearing either a 1,3-diaminopropyl or a 1H-benzotriazolyl residue, showed a BChE selective inhibition in the single-digit micro-molar range without being cytotoxic up to 30μM. In silico molecular docking studies on the active sites of AChE and BChE were performed to gain a molecular insight into the mode of action of these compounds and to explain the pronounced selectivity for BChE. Copyright © 2014 Elsevier Ltd. All rights reserved.

Incorporation of Oxygen into Abscisic Acid and Phaseic Acid from Molecular Oxygen 1

Science.gov (United States)

Creelman, Robert A.; Zeevaart, Jan A. D.

1984-01-01

Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% 18O2 and 80% N2 indicates that one atom of 18O is incorporated in the 6′-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase. Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing 18O2 indicates that one atom of 18O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1′-, 4′-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1′- and 4′-positions of abscisic acid which is converted to abscisic acid under conditions of water stress. PMID:16663564

A theoretical study of electrical and electrochemical properties of dicyanomethylene derivatives of squaric acid

Energy Technology Data Exchange (ETDEWEB)

Xue Zhaoming [Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China) and Department of Chemistry, Anhui University, Hefei, Anhui 230039 (China)]. E-mail: zmxue@ahu.edu.cn; Liu Bing [Department of Chemistry, Anhui University, Hefei, Anhui 230039 (China); Chen Chunhua [Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2006-06-01

Theoretical studies on anions of 1,2-dihydroxycyclobuten-3,4-dione (squaric acid, H{sub 2}SQ) and the whole series of dicyanomethylene derivatives in gas-phase and in acetonitrile (AN) solution are carried out using density functional theory (DFT) and SCRF-DFT method at B3LYP theory level for the first time. Natural bond orbital (NBO) analyses indicate that {pi}-electron delocalization in the series is stronger. Based on the most stable conformations, a linear correlation was observed between the highest occupied molecular orbital (HOMO) energies, or ionization potential (I{sub p}) and the oxidation potentials measured by cyclic voltammetry, which supports experimental results that systematic substitution of the oxygen atoms in the C{sub 4}O{sub 4}{sup 2-} structure with C(CN){sub 2} groups causes a shift of both the oxidation potentials E{sub 1}{sup 0} and E{sub 2}{sup 0} towards more positive values, indicating that a consistent delocalization of the negative charge is exerted by these substituents and monoanions are more resistant against oxidation than their counterparts-dianions. The correlations were also observed between experimental K{sub sem} and Gibbs free energy calculated in AN solution. The calculated gas-phase relative basicity of the six dianions follows the order SQ{sup 2-}>4-CDCB{sup 2-}>2,4-CDCB{sup 2-}>3,4-CDCB{sup 2-}>2,3,4-CDCB{sup 2-}>1,2,3,4-CDCB{sup 2-} which support the experimental results that the dianions SQ{sup 2-} and 4-CDCB{sup 2-} can be protonated, in strongly acidic medium, to the corresponding monoanions, whereas no protonation occurs in the case of di-, tri- and tetra-substituted compounds.

Synthesis of Gibberellic Acid Derivatives and Their Effects on Plant Growth

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Hao Tian

2017-04-01

Full Text Available A series of novel C-3-OH substituted gibberellin derivatives bearing an amide group were designed and synthesized from the natural product gibberellic acid (GA3. Their activities on the plant growth regulation of rice and Arabidopsis were evaluated in vivo. Among these compounds, 10d and 10f exhibited appreciable inhibitory activities on rice (48.6% at 100 μmol/L and Arabidopsis (41.4% at 100 μmol/L, respectively. These results provide new insights into the design and synthesis of potential plant growth regulators.

Amino acid linked bromobenzoyl thiourea derivatives: syntheses, characterization and antimicrobial activities

International Nuclear Information System (INIS)

Raheel, A.; Din, I.U.; Badshah, A.; Rauf, M.K.; Andleeb, S.

2016-01-01

Five new bromobenzoyl thiourea derivatives (1-5) linked with different amino acids were synthesized via the reaction of bromobenzoyl chloride with potassium thiocyanide and the corresponding amines. The synthetic compounds were characterized by single crystal XRD, IR and NMR (/sup 1/H- and /sup 13/C-) spectroscopy in addition to elemental analysis and melting point determinations. These compounds were also preliminary analyzed for antifungal and antibacterial activity against different strains of fungi and bacteria, respectively. The data suggest that the compounds exhibited promising antimicrobial activity and may prove potential lead compounds as antimicrobial agent. (author)

Synthesis and antitumour activity of arctigenin amino acid ester derivatives against H22 hepatocellular carcinoma.

Science.gov (United States)

Cai, Enbo; Guo, Shijie; Yang, Limin; Han, Mei; Xia, Jing; Zhao, Yan; Gao, Xiaorui; Wang, Yu

2018-02-01

Arctigenin (ARG) is famous in its abundant pharmacological activity. However, many researches in it entered the bottleneck period because of its poor water solubility. The derivatives of ARG have been synthesised with five amino acids which have t-Butyloxy carbonyl (BOC) as a protective group. We examined the effects of removing BOC. The results showed that the amino acid derivatives without protective group have better water solubility and nitrite-clearing ability than ARG. Based on these results, ARG6' and ARG9' were selected at a dosage of 40 mg/kg to evaluate their antitumour activity. The percentage inhibition rate of ARG6' and ARG9' were 55.87 and 51.40, respectively, which was twice as much as ARG. Furthermore, they could increase liver and kidney indexes and produce less damage in these organs. In brief, this study provides a basis for new drug development.

Graphene/dodecanol floating solidification microextraction for the preconcentration of trace levels of cinnamic acid derivatives in traditional Chinese medicines.

Science.gov (United States)

Hu, Shuang; Yang, Xiao; Xue, Jiao; Chen, Xuan; Bai, Xiao-Hong; Yu, Zhi-Hui

2017-07-01

A novel graphene/dodecanol floating solidification microextraction followed by HPLC with diode-array detection has been developed to extract trace levels of four cinnamic acid derivatives in traditional Chinese medicines. Several parameters affecting the performance were investigated and optimized. Also, possible microextraction mechanism was analyzed and discussed. Under the optimum conditions (amount of graphene in dodecanol: 0.25 mg/mL; volume of extraction phase: 70 μL; pH of sample phase: 3; extraction time: 30   min; stirring rate: 1000 rpm; salt amount: 26.5% NaCl; volume of sample phase: 10 mL, and without dispersant addition), the enrichment factors of four cinnamic acid derivatives ranged from 26 to 112, the linear ranges were 1.0 × 10 -2 -10.0 μg/mL for caffeic acid, 1.3 × 10 -3 -1.9 μg/mL for p-hydroxycinnamic acid, 2.8 × 10 -3 -4.1 μg/mL for ferulic acid, and 2.7 × 10 -3 -4.1 μg/mL for cinnamic acid, with r 2 ≥ 0.9993. The detection limits were found to be in the range of 0.1-1.0 ng/mL, and satisfactory recoveries (92.5-111.2%) and precisions (RSDs 1.1-9.5%) were also achieved. The results showed that the approach is simple, effective and sensitive for the preconcentration and determination of trace levels of cinnamic acid derivatives in Chinese medicines. The proposed method was compared with conventional dodecanol floating solidification microextraction and other extraction methods. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Measurement of local cerebral protein synthesis in vivo: influence of recycling of amino acids derived from protein degradation

International Nuclear Information System (INIS)

Smith, C.B.; Deibler, G.E.; Eng, N.; Schmidt, K.; Sokoloff, L.

1988-01-01

A quantitative autoradiographic method for the determination of local rates of protein synthesis in brain in vivo is being developed. The method employs L-[1- 14 C]leucine as the radiolabeled tracer. A comprehensive model has been designed that takes into account intracellular and extracellular spaces, intracellular compartmentation of leucine, and the possibility of recycling of unlabeled leucine derived from steady-state degradation of protein into the precursor pool for protein synthesis. We have evaluated the degree of recycling by measuring the ratio of the steady-state precursor pool distribution space for labeled leucine to that of unlabeled leucine. The values obtained were 0.58 in whole brain and 0.47 in liver. These results indicate that there is significant recycling of unlabeled amino acids derived from steady-state protein degradation in both tissues. Any method for the determination of rates of cerebral protein synthesis in vivo with labeled tracers that depends on estimation of precursor pool specific activity in tissue from measurements in plasma must take this recycling into account

A new p-hydroxybenzoic acid derivative from an endophytic fungus Penicillium sp. of Nerium indicum.

Science.gov (United States)

Ma, Yang-Min; Qiao, Ke; Kong, Yang; Guo, Lin-Xin; Li, Meng-Yun; Fan, Chao

2017-12-01

A new p-hydroxybenzoic acid derivative named 4-(2'R, 4'-dihydroxybutoxy) benzoic acid (1) was isolated from the fermentation of Penicillium sp. R22 in Nerium indicum. The structure was elucidated by means of spectroscopic (HR-ESI-MS, NMR, IR, UV) and X-ray crystallographic methods. The antibacterial and antifungal activity of compound 1 was tested, and the results showed that compound 1 revealed potent antifungal activity against Colletotrichum gloeosporioides, Alternaria alternata, and Alteranria brassicae with MIC value of 31.2 μg/ml.

Esterification from derivates of styrene by acetic acid using perchloric acid as a catalyzer; Esterificacion de derivados de estireno con acido acetico en presencia de acido perclorico como catalizador

Energy Technology Data Exchange (ETDEWEB)

Martinez de la Cuesta, P.J.; Rus Martinez, E.; Palomino sosa, R.; Palomino Perez, F. I. [Departamento deIngenieria Quimica, Facultad de Ciencias, Universidad de Malaga, Malaga (Spain)

1995-11-01

The present work is focused to develop the production of esters from derivatives of styrene by acetic acid using perchloric acid as a catalyst. The kinetics of the reaction was studied and analysis of the variables was carried out. 18 refs.

Correlations between retention indices and molecular structure of their benzoyl derivatives on phenyl substituted polysiloxane stationary phases

International Nuclear Information System (INIS)

Pias, J.B.; Gasco, L.

1976-01-01

The retention indices of aliphaticalcohols of carbon number up to Csub(g), and of their benzoyl derivatives up to C 7 , were determined in columns packed with Chromosorb G (AW-DMCS-HP) coated previously with 5% methyl, and methyl phenyl polysiloxanes with increasing polarity (SE-30, OV-3, OV-7; OV-11, OV-17 and OV-25). Correlations between retention indices and chain length for 1-alcohols, 2-alcohols, 3-alcohols, 1, on -3-alcohols, 2-methyl-1-alcohols and for their corresponding benzoyl derivatives were calculated at 100, 120 and 140 0 C. In alcohols, a -CH 2 - group increases I approximately 100 units, and in their benzoyl derivatives from 80 to 100 units. Dispersion indices ΔI, and positional and structural increments of I were evaluated for -OH and benzoyl groups in terms for phase polarity and chain length. Effects of chain length, chain branching and double bond location on retention parameters were also studied. (author)

Derivatives of valproic acid are active against pentetrazol-induced seizures in immature rats

Czech Academy of Sciences Publication Activity Database

Mareš, Pavel; Kubová, Hana; Hen, N.; Yagen, B.; Bialer, M.

2013-01-01

Roč. 106, 1-2 (2013), s. 64-73 ISSN 0920-1211 R&D Projects: GA ČR(CZ) GAP304/10/1274; GA ČR(CZ) GBP304/12/G069 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : experimental seizures * anticonvulsant action * derivatives of valproic acid * immature rats Subject RIV: FH - Neurology Impact factor: 2.190, year: 2013

Reducing Renal Uptake of {sup 177}Lu Labeled CCK Derivative using Basic Amino Acids

Energy Technology Data Exchange (ETDEWEB)

Lee, Soyoung; Lim, Jaecheong; Joh, Eunha [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-05-15

Radiolabeled peptides have been designed to target the relative receptors overespressed in tumor cells, such as integrin αvβ3, gastrin-releasing peptide receptor (GRPR), melanocortin-1 receptor (MC1-R), glucagon-like peptide-a receptor (GLP-1R), and cholecystokinin (CCK) receptor. Most of these peptides are eliminated from the body via the kidney and are partly reabsorbed in the proximal tubular cells. However, the high renal uptake of the radiolabeled peptides may lead to renal toxicity. In this study we investigated various amino acid solutions to reduce the renal uptake of {sup 177}Lu-DOTA-CCK derivative. Renal uptake of {sup 177}Lu-DOTA-CCK derivative is effectively reduced by the administration of positively charged amino acids. The administration of 12 mg of L-lysine was as effective in reducing the renal uptake as 6 mg of lysine and 6 mg of arginine combinations. Further studies will be performed to identify the most potent inhibitor of renal reuptake of radiolabeled peptides and minimize the chance of unwanted side effects.

Correlating enzymatic browning inhibition and antioxidant ability of Maillard reaction products derived from different amino acids.

Science.gov (United States)

Xu, Haining; Zhang, Xiaoming; Karangwa, Eric; Xia, Shuqin

2017-09-01

Up to now, only limited research on enzymatic browning inhibition capacity (BIC) of Maillard reaction products (MRPs) has been reported and there are still no overall and systematic researches on MRPs derived from different amino acids. In the present study, BIC and antioxidant capacity, including 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and Fe 2+ reducing power activity, of the MRPs derived from 12 different amino acids and three reducing sugars were investigated. The MRPs of cysteine (Cys), cystine, arginine (Arg) and histidine (His) showed higher BIC compared to other amino acids. Lysine (Lys)-MRPs showed the highest absorbance value at 420 nm (A 420 ) but very limited BIC, whereas Cys-MRPs, showed the highest BIC and the lowest A 420 . The A 420 can roughly reflect the trend of BIC of MRPs from different amino acids, except Cys and Lys. MRPs from tyrosine (Tyr) showed the most potent antioxidant capacity but very limited BIC, whereas Cys-MRPs showed both higher antioxidant capacity and BIC compared to other amino acids. Partial least squares regression analysis showed positive and significant correlation between BIC and Fe 2+ reducing power of MRPs from 12 amino acids with glucose or fructose, except Lys, Cys and Tyr. The suitable pH for generating efficient browning inhibition compounds varies depending on different amino acids: acidic pH was favorable for Cys, whereas neutral and alkaline pH were suitable for His and Arg, respectively. Increasing both heating temperature and time over a certain range could improve the BIC of MRPs of Cys, His and Arg, whereas any further increase deteriorates their browning inhibition efficiencies. The types of amino acid, initial pH, temperature and time of the Maillard reaction were found to greatly influence the BIC and antioxidant capacity of the resulting MRPs. There is no clear relationship between BIC and the antioxidant capacity of MRPs when reactant type and processing parameters of the Maillard

Evaluation of mental stress by physiological indices derived from finger plethysmography.

Science.gov (United States)

Minakuchi, Emiko; Ohnishi, Eriko; Ohnishi, Junji; Sakamoto, Shigeko; Hori, Miyo; Motomura, Miwa; Hoshino, Junichi; Murakami, Kazuo; Kawaguchi, Takayasu

2013-10-12

Quantitative evaluation of mental stress is important to prevent stress-related disorders. Finger plethysmography (FPG) is a simple noninvasive method to monitor peripheral circulation, and provides many physiological indices. Our purpose is to investigate how FPG-derived indices reflect on mental stress, and to clarify any association between these physiological indices and subjective indices of mental stress. Thirty-one healthy women (mean age, 22 years ± 2) participated. The participants rested by sitting on a chair for 10 min. They then performed a computerized version of the Stroop color-word conflict test (CWT) for 10 min. Finally, they rested for 10 min. FPG was recorded throughout the experiment. The participants completed a brief form of the Profile of Mood States (POMS) questionnaire before and after the test. Using the FPG data, we conducted chaos analysis and fast Fourier transform analysis, and calculated chaotic attractors, the largest Lyapunov exponent, a high-frequency (HF) component, a low-to-high-frequency (LF/HF) ratio, finger pulse rate and finger pulse wave amplitude. The HF component decreased and the LF/HF ratio increased significantly during the test (P stress. Our findings indicate that FPG is one of the easiest methods to evaluate mental stress quantitatively. In particular, the largest Lyapunov exponent and the LF/HF ratio might be associated with acute mental stress. Farther examination is needed to find any association between the physiological indices and various types of mental stress.

Metal cation dependence of interactions with amino acids: bond dissociation energies of Rb(+) and Cs(+) to the acidic amino acids and their amide derivatives.

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Armentrout, P B; Yang, Bo; Rodgers, M T

2014-04-24

Metal cation-amino acid interactions are key components controlling the secondary structure and biological function of proteins, enzymes, and macromolecular complexes comprising these species. Determination of pairwise interactions of alkali metal cations with amino acids provides a thermodynamic vocabulary that begins to quantify these fundamental processes. In the present work, we expand a systematic study of such interactions by examining rubidium and cesium cations binding with the acidic amino acids (AA), aspartic acid (Asp) and glutamic acid (Glu), and their amide derivatives, asparagine (Asn) and glutamine (Gln). These eight complexes are formed using electrospray ionization and their bond dissociation energies (BDEs) are determined experimentally using threshold collision-induced dissociation with xenon in a guided ion beam tandem mass spectrometer. Analyses of the energy-dependent cross sections include consideration of unimolecular decay rates, internal energy of the reactant ions, and multiple ion-neutral collisions. Quantum chemical calculations are conducted at the B3LYP, MP2(full), and M06 levels of theory using def2-TZVPPD basis sets, with results showing reasonable agreement with experiment. At 0 and 298 K, most levels of theory predict that the ground-state conformers for M(+)(Asp) and M(+)(Asn) involve tridentate binding of the metal cation to the backbone carbonyl, amino, and side-chain carbonyl groups, although tridentate binding to the carboxylic acid group and side-chain carbonyl is competitive for M(+)(Asn). For the two longer side-chain amino acids, Glu and Gln, multiple structures are competitive. A comparison of these results to those for the smaller alkali cations, Na(+) and K(+), provides insight into the trends in binding energies associated with the molecular polarizability and dipole moment of the side chain. For all four metal cations, the BDEs are inversely correlated with the size of the metal cation and follow the order Asp < Glu

Staphylococcus aureus utilizes host-derived lipoprotein particles as sources of exogenous fatty acids.

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Delekta, Phillip C; Shook, John C; Lydic, Todd A; Mulks, Martha H; Hammer, Neal D

2018-03-26

Methicillin-resistant Staphylococcus aureus (MRSA) is a threat to global health. Consequently, much effort has focused on the development of new antimicrobials that target novel aspects of S. aureus physiology. Fatty acids are required to maintain cell viability, and bacteria synthesize fatty acids using the type II fatty acid synthesis pathway (FASII). FASII is significantly different from human fatty acid synthesis, underscoring the therapeutic potential of inhibiting this pathway. However, many Gram-positive pathogens incorporate exogenous fatty acids, bypassing FASII inhibition and leaving the clinical potential of FASII inhibitors uncertain. Importantly, the source(s) of fatty acids available to pathogens within the host environment remains unclear. Fatty acids are transported throughout the body by lipoprotein particles in the form of triglycerides and esterified cholesterol. Thus, lipoproteins, such as low-density lipoprotein (LDL) represent a potentially rich source of exogenous fatty acids for S. aureus during infection. We sought to test the ability of LDLs to serve as a fatty acid source for S. aureus and show that cells cultured in the presence of human LDLs demonstrate increased tolerance to the FASII inhibitor, triclosan. Using mass spectrometry, we observed that host-derived fatty acids present in the LDLs are incorporated into the staphylococcal membrane and that tolerance to triclosan is facilitated by the fatty acid kinase A, FakA, and Geh, a triacylglycerol lipase. Finally, we demonstrate that human LDLs support the growth of S. aureus fatty acid auxotrophs. Together, these results suggest that human lipoprotein particles are a viable source of exogenous fatty acids for S. aureus during infection. IMPORTANCE Inhibition of bacterial fatty acid synthesis is a promising approach to combating infections caused by S. aureus and other human pathogens. However, S. aureus incorporates exogenous fatty acids into its phospholipid bilayer. Therefore, the

Water column distribution of phospholipid-derived fatty acids of marine microorganisms in the Humboldt Current system off northern Chile

Science.gov (United States)

Espinosa, Luisa F.; Pantoja, Silvio; Pinto, Luis A.; Rullkötter, Jürgen

2009-07-01

Suspended particulate matter samples from the oxygenated surface zone, the oxygen minimum zone, and the oxygenated deeper zone were collected from the upwelling area off Antofagasta in northern Chile during austral autumn (April 2001) to study the composition of microbial phospholipid-derived fatty acid methyl esters, using capillary gas chromatography-mass spectrometry. Whereas phytoplanktonic carbon dominated living organic matter near the coast, bacterial carbon was most abundant offshore. The biomarker distribution showed some differences between the depth levels sampled, such as the highest microbial abundance in the epipelagic zone represented by phytoplankton, especially diatoms, and a homogeneous distribution of bacterial biomarkers, with no indication of vertical segregation of functional groups as previously thought.

Bioreversible Derivatives of Phenol. 2. Reactivity of Carbonate Esters with Fatty Acid-like Structures Towards Hydrolysis in Aqueous Solutions

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Claus Larsen

2007-10-01

Full Text Available A series of model phenol carbonate ester prodrugs encompassing derivatives with fatty acid-like structures were synthesized and their stability as a function of pH (range 0.4 – 12.5 at 37°C in aqueous buffer solutions investigated. The hydrolysis rates in aqueous solutions differed widely, depending on the selected pro-moieties (alkyl and aryl substituents. The observed reactivity differences could be rationalized by the inductive and steric properties of the substituent groups when taking into account that the mechanism of hydrolysis may change when the type of pro-moiety is altered, e.g. n-alkyl vs. t-butyl. Hydrolysis of the phenolic carbonate ester 2-(phenoxycarbonyloxy-acetic acid was increased due to intramolecular catalysis, as compared to the derivatives synthesized from ω-hydroxy carboxylic acids with longer alkyl chains. The carbonate esters appear to be less reactive towards specific acid and base catalyzed hydrolysis than phenyl acetate. The results underline that it is unrealistic to expect that phenolic carbonate ester prodrugs can be utilized in ready to use aqueous formulations. The stability of the carbonate ester derivatives with fatty acid-like structures, expected to interact with the plasma protein human serum albumin, proved sufficient for further in vitro and in vivo evaluation of the potential of utilizing HSA binding in combination with the prodrug approach for optimization of drug pharmacokinetics.

Correction: Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones.

Science.gov (United States)

Yin, Feng; Garifullina, Ainash; Tanaka, Fujie

2018-04-25

Correction for 'Synthesis of pyrrolidine-3-carboxylic acid derivatives via asymmetric Michael addition reactions of carboxylate-substituted enones' by Feng Yin et al., Org. Biomol. Chem., 2017, 15, 6089-6092.

Root-uptake of 14C derived from acetic acid and 14C transfer to rice edible parts

International Nuclear Information System (INIS)

Ogiyama, Shinichi; Suzuki, Hiroyuki; Inubushi, Kazuyuki; Takeda, Hiroshi; Uchida, Shigeo

2010-01-01

Three types of culture experiments using paddy rice (Oryza sativa L.) were performed to examine root-uptake of 14 C in the form of acetic acid: double pot experiment (hydroponics), wet culture experiment (submerged sand medium), and chamber experiment (hydroponics and submerged sand medium). The 14 C radioactivity in the plant, mediums, and atmospheric carbon dioxide ( 14 CO 2 ) in the chamber were determined, and the distribution of 14 C in the plant was visualized using autoradiography. In the double pot experiment, the shoot of the plant and the lower root which was soaked in the culture solution had 14 C radioactivity, but the upper root which did not have contact with the solution had none. There were also 14 C radioactivity in the grains and roots in the wet culture experiment. Results of the chamber experiment showed that 14 CO 2 gas was released from the culture solution in both types of cultures. Results indicated that the 14 C-acetic acid absorbed by rice plant through its root would be very small. Most of the 14 C-acetic acid was transformed into gaseous forms either in the culture solution or rhizosphere. A relatively longer time would be needed to assimilate 14 C derived from acetic acid to grain parts after it was once absorbed by the shoot through the root. Availability of 14 C for the plant in sand culture was considered to be decreased compared with that for the plant in the hydroponics experiment. It was suggested that rice plant absorbed and assimilated 14 C through the plant roots not because of uptake of 14 C-acetic acid but because of uptake of 14 C in gaseous forms such as 14 CO 2 .

Eutectic behaviour of binary mixtures composed of two isomeric lactic acid derivatives

Czech Academy of Sciences Publication Activity Database

Bubnov, Alexej; Podoliak, Natalia; Hamplová, Věra; Tomášková, Petra; Havlíček, Jaroslav; Kašpar, Miroslav

2016-01-01

Roč. 495, č. 1 (2016), s. 105-115 ISSN 0015-0193 R&D Projects: GA ČR GA16-12150S; GA MŠk(CZ) LH15305; GA MŠk(CZ) LD14007; GA ČR GA15-02843S Grant - others:EU - ICT(XE) COST Action IC1208 Institutional support: RVO:68378271 Keywords : ferroelectric smectic phase * binary mixture * lactic acid derivative * isomer * phase diagram * self-assembling behaviour Subject RIV: JJ - Other Materials Impact factor: 0.551, year: 2016

Isolation of Cinnamic Acid Derivatives from the Bulbs of Allium tripedale

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Zahra Chehri

2018-01-01

Full Text Available Background: Allium genus with 750 species is the most diverse genus in the Amaryllidaceae family. Historically, Allium species have been used as medicinal plants, especially for prevention and treatment of cardiovascular diseases and considered as valuable sources of phytonutrients. Phytochemical investigation of Allium tripedale, locally called “Anashq,” which is an edible plant of the “Zagros” region (west of Iran was conducted in the present study. Materials and Methods: Air-dried bulbs of the plant were extracted in a four-step extraction method with increasing polarity using hexane, chloroform, chloroform–methanol (9:1, and methanol. Chloroform-methanol (9:1 extract was fractionated by medium-pressure liquid chromatography on a RP-18 column using a linear gradient solvent system of H2O to MeOH. Phenolic-rich fractions were subjected to the final isolation and purification of the constituents by reversed-phase high-performance liquid chromatography method. Structure elucidation of the compounds was performed through comprehensive methods including 1D-and 2D-NMR and mass spectroscopy. Results: Two cinnamic acid derivatives were isolated from the bulbs of A. tripedale; using spectroscopic methods, their chemical structures were determined as 6,7-dimethoxy N-trans-caffeoyltyramine (1 and N-trans-feruloyltyramine (2. Conclusion: Cinnamic acid derivatives are pharmacologically active phenolic compounds, which have been isolated from different Allium species. Isolation of these compounds from A. tripedale is reported for the first time in this study and could be used as a chemical basis for explanation of the plant biological and pharmacological activities.

Analysis of Citric Acid in Beverages: Use of an Indicator Displacement Assay

Science.gov (United States)

Umali, Alona P.; Anslyn, Eric V.; Wright, Aaron T.; Blieden, Clifford R.; Smith, Carolyne K.; Tian, Tian; Truong, Jennifer A.; Crumm, Caitlin E.; Garcia, Jorge E.; Lee, Soal; Mosier, Meredith; Nguyen, Chester P.

2010-01-01

The use of an indicator displacement assay permits the visualization of binding events between host and guest molecules. An undergraduate laboratory experiment is described to demonstrate the technique in the determination of citric acid content in commercially available beverages such as soda pop and fruit juices. Through the technique, students…

A green protocol for the synthesis of quinoxaline derivatives catalyzed by polymer supported sulphanilic acid

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Umesh P. Tarpada

2017-05-01

Full Text Available Polymer supported sulphanilic acid was found to be an effective heterogeneous catalyst for one pot synthesis of various quinoxaline derivatives from the condensation reaction between 1,2-diamines and 1,2-dicarbonyl compounds in ethanol. Synthesis was attempted under reflux as well as at room temperature using ethanol as the solvent to afford excellent yields. Heterogeneity of the catalyst allowed its recycling for five times with almost retention in catalytic activity. Prepared quinoxaline derivatives were also tested for their antioxidant activity by the FRAP assay method.

Amino Acid Conjugated Anthraquinones from the Marine-Derived Fungus Penicillium sp. SCSIO sof101.

Science.gov (United States)

Luo, Minghe; Cui, Zhaomeng; Huang, Hongbo; Song, Xianqin; Sun, Aijun; Dang, Yongjun; Lu, Laichun; Ju, Jianhua

2017-05-26

Emodacidamides A-H (1-8), natural products featuring anthraquinone-amino acid conjugates, have been isolated from a marine-derived fungus, Penicillium sp. SCSIO sof101, together with known anthraquinones 9 and 10. The planar structures of 1-8 were elucidated using a combination of NMR spectroscopy and mass spectrometry. The absolute configurations of the amino acid residues were confirmed using Marfey's method and chiral-phase HPLC analyses. Additionally, isolates were evaluated for possible immunomodulatory and cytotoxic activities. Emodacidamides A (1), C (3), D (4), and E (5) inhibited interleukin-2 secretion from Jurkat cells with IC 50 values of 4.1, 5.1, 12, and 5.4 μM, respectively.

Synthesis and Antibacterial Evaluation of New N-acylhydrazone Derivatives from Dehydroabietic Acid

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Wen Gu

2012-04-01

Full Text Available A series of new N-acylhydrazone derivatives were synthesized in good yields through the reactions of dehydroabietic acid hydrazide with a variety of substituted arylaldehydes. The structures of the synthesized compounds were confirmed by IR, ¹H- and ¹³C-NMR, ESI-MS, elemental analysis and single crystal X-ray diffraction. From the crystal structure of compound 4l, the C=N double bonds of these N-acylhydrazones showed (E-configuration, while the NMR data of compounds 4a–q indicated the existence of two rotamers for each compound in solution. The target compounds were evaluated for their antibacterial activities against four microbial strains. The result suggested that several compounds exhibited pronounced antibacterial activities. Particularly, compound 4p exhibited good antibacterial activity against Staphylococcus aureus and Bacillus subtilis comparable to positive control. The possible antibacterial metabolism and the strategy for further optimization of this compound were also discussed.

Teratology study of amide derivatives of branched aliphatic carboxylic acids with 4-aminobenzensulfonamide in NMRI mice.

Science.gov (United States)

Onishi, Yuko; Okada, Akinobu; Noyori, Hiroko; Okamura, Ai; Hen, Naama; Yagen, Boris; Bialer, Meir; Fujiwara, Michio

2013-08-01

Valproic acid (VPA), widely used to treat epilepsy, bipolar disorders, and migraine prophylaxis, is known to cause neural tube and skeletal defects in humans and animals. Aminobenzensulfonamide derivatives of VPA with branched aliphatic carboxylic acids, namely 2-methyl-N-(4-sulfamoyl-phenyl)-pentanamide (MSP), 2-ethyl-N-(4-sulfamoyl-phenyl)-butyramide (ESB), 2-ethyl-4-methyl-N-(4-sulfamoyl-phenyl)-pentanamide (EMSP), and 2-ethyl-N-(4-sulfamoyl-benzyl)-butyramide (ESBB), have shown more potent anticonvulsant activity than VPA in preclinical testing. Here, we investigated the teratogenic effects of these analogous compounds of VPA in NMRI mice. Pregnant NMRI mice were given a single subcutaneous injection of either VPA at 1.8 or 3.6 mmol/kg, or MSP, ESB, EMSP, or ESBB at 1.8, 3.6, or 4.8 mmol/kg on gestation day (GD) 8. Cesarean section was performed on GD 18, and the live fetuses were examined for external and skeletal malformations. Compared with VPA, which induced neural tube defects (NTDs) in fetuses at 1.8 and 3.6 mmol/kg, the analog derivatives induced no NTDs at dose levels up to 4.8 mmol/kg (except for a single case of exencephaly at 4.8 mmol/kg MSP). Skeletal examination showed several abnormalities mainly at the axial skeletal level with VPA at 1.8 mmol/kg. Fused vertebrae and/or fused ribs were also observed with MSP, ESB, EMSP, and ESBB, they were less severe and seen at a lower incidence that those induced by VPA at the same dose level. In addition to exerting more potent preclinical antiepileptic activity, teratology comparison indicates that aminobenzensulfonamide analogs are generally more weakly teratogenic than VPA. © 2013 Wiley Periodicals, Inc.

Continuous Autoregulatory Indices Derived from Multi-modal Monitoring: Each One is Not Like the Other.

OpenAIRE

Zeiler, Frederick; Donnelly, Joseph; Menon, David Krishna; Smieleweski, P; Zweifel, C; Brady, K; Czosnyka, Marek

2017-01-01

We assess the relationships between various continuous measures of autoregulatory capacity in an adult TBI cohort. We assessed relationships between autoregulatory indices derived from intracranial pressure (ICP: PRx, PAx, RAC), Transcranial Doppler (TCD: Mx, Sx, Dx), brain tissue-oxygenation (ORx), and spatially resolved near infrared spectroscopy (NIRS resolved: TOx, THx). Relationships between indices were assessed using Pearson correlation coefficient, Friedman (KW) test, Principle compon...

Preparation and characterization of polymer blends based on recycled PET and polyester derived by terephthalic acid

International Nuclear Information System (INIS)

Ohara, L.; Miranda, C.S.; Fiuza, R.P.; Luporini, S.; Carvalho, R.F.; Jose, N.M.

2010-01-01

Environmentally friendly materials, made from industrial waste, are being increasingly used as a solution to the growing amount of waste generated by society, but also as a cheaper alternative to replace conventional materials for use in construction. In this work were investigated the properties of polymer blends based on recycled PET and a polyester derived from terephthalic acid and glycerin, a co-product of biodiesel. The samples were characterized by XRD, TGA, DSC, FTIR and SEM. The polyester synthesized showed a degradation event near 300 deg C. The blends with higher ratio of PET showed thermal behavior similar to pure PET. The X-ray diffraction showed that the polymer blends are semicrystalline materials. The micrographs presents the presence of a smooth surface, indicating the possibility of miscibility between the arrays. Therefore, the blending makes possible the fabrication of low-cost materials with applications in several areas. (author)

Amino acid sequence of bovine muzzle epithelial desmocollin derived from cloned cDNA: a novel subtype of desmosomal cadherins.

Science.gov (United States)

Koch, P J; Goldschmidt, M D; Walsh, M J; Zimbelmann, R; Schmelz, M; Franke, W W

1991-05-01

Desmosomes are cell-type-specific intercellular junctions found in epithelium, myocardium and certain other tissues. They consist of assemblies of molecules involved in the adhesion of specific cell types and in the anchorage of cell-type-specific cytoskeletal elements, the intermediate-size filaments, to the plasma membrane. To explore the individual desmosomal components and their functions we have isolated DNA clones encoding the desmosomal glycoprotein, desmocollin, using antibodies and a cDNA expression library from bovine muzzle epithelium. The cDNA-deduced amino-acid sequence of desmocollin (presently we cannot decide to which of the two desmocollins, DC I or DC II, this clone relates) defines a polypeptide with a calculated molecular weight of 85,000, with a single candidate sequence of 24 amino acids sufficiently long for a transmembrane arrangement, and an extracellular aminoterminal portion of 561 amino acid residues, compared to a cytoplasmic part of only 176 amino acids. Amino acid sequence comparisons have revealed that desmocollin is highly homologous to members of the cadherin family of cell adhesion molecules, including the previously sequenced desmoglein, another desmosome-specific cadherin. Using riboprobes derived from cDNAs for Northern-blot analyses, we have identified an mRNA of approximately 6 kb in stratified epithelia such as muzzle epithelium and tongue mucosa but not in two epithelial cell culture lines containing desmosomes and desmoplakins. The difference may indicate drastic differences in mRNA concentration or the existence of cell-type-specific desmocollin subforms. The molecular topology of desmocollin(s) is discussed in relation to possible functions of the individual molecular domains.

Ion associates of rare earth elements with salicylic acid derivatives and rhodamine B and their analytical application

Energy Technology Data Exchange (ETDEWEB)

Tselik, E I; Poluehktov, N S; Mishchenko, V T [AN Ukrainskoj SSR, Odessa. Fiziko-Khimicheskij Inst.

1979-10-01

The determination of rare earth elements by extraction photometry (fluorimetric) technique with the use of salicylic acid derivatives and Rhodamine B is reported. The best results in the determination of REE in the form of ionic associates between their acidocomplexes and Rhodamine B are obtained with the use of 3,5-diiodinesalicylic acid. The ratio between components in the compounds formed and the conditions of extraction are determined.

Melamine derivatives as effective corrosion inhibitors for mild steel in acidic solution: Chemical, electrochemical, surface and DFT studies

Science.gov (United States)

Verma, Chandrabhan; Haque, J.; Ebenso, Eno E.; Quraishi, M. A.

2018-06-01

In present study two condensation products of melamine (triazine) and glyoxal namely, 2,2-bis(4,6-diamino-1,3,5-triazin-2-ylamino)acetaldehyde (ME-1) and (N2,N2‧E,N2,N2‧E)-N2,N2‧-(ethane-1,2-diylidene)-bis-(1,3,5-triazine-2,4,6-triamine) (ME-2) are tested as mild steel corrosion inhibitors in acidic solution (1M HCl). The inhibition efficiency of ME-1 and ME-2 increases with increase in their concentrations and maximum values of 91.47% and 94.88% were derived, respectively at 100 mgL-1 (34.20 × 10-5 M) concentration. Adsorption of ME-1 and ME-2 on the surface of metal obeyed the Langmuir adsorption isotherm. Polarization investigation revealed that ME-1 and ME-2 act as mixed type inhibitors with minor cathodic prevalence. The chemical and electrochemical analyses also supported by surface characterization methods where significant smoothness in the surface morphologies was observed in the images of SEM and AFM spectra. Several DFT indices such as EHOMO and ELUMO, ΔE, η, σ, χ, μ and ΔN were derived for both ME-1 and ME-2 molecules and correlated with experimental results. The DFT studies have also been carried out for protonated or cationic form of the inhibitor molecules by considering that in acidic medium the heteroatoms of organic inhibitors easily undergo protonation. The experimental and density functional theory (DFT) studies (neutral and protonated) were in good agreement.

Effects of Salicylic acid and Humic acid on Vegetative Indices of Periwinkle (Catharanthus roseusL.

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E. Chamani

2016-07-01

greatest impact on the number of pods. The results showed that treatment with 1000 mg/l salicylic acid and humic acid had the greatest effect on stem diameter. Conclusion: The results of this study indicated that low concentrations of salicylic acid increased plant height, the number of leaves, chlorophyll content and stomatal conductance, which can increase plant resistance against unfavorable environmental conditions. As a result, the plants treated with salicylic acid can be increased two driven in adverse environmental conditions. The treatment of humic acid by increasing the rate of photosynthesis and increases the amount of material available for plant growth. This increase can accelerate the growth of the main branch and side periwinkle plant medicinal plants and enhances the appearance of the plant.

Radioiodinated phenylalkyl malonic acid derivatives as pH-sensitive SPECT tracers.

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Matthias Bauwens

Full Text Available INTRODUCTION: In vivo pH imaging has been a field of interest for molecular imaging for many years. This is especially important for determining tumor acidity, an important driving force of tumor invasion and metastasis formation, but also in the process of apoptosis. METHODS: 2-(4-[(123I]iodophenethyl-2-methylmalonic acid (IPMM, 2-(4-[(123I]iodophenethyl-malonic acid (IPM, 2-(4-[(123I]iodobenzyl-malonic acid (IBMM and 4-[(123I]iodophthalic acid (IP were radiolabeled via the Cu(+ isotopic nucleophilic exchange method. All tracers were tested in vitro in buffer systems to assess pH driven cell uptake. In vivo biodistribution of [(123I]IPMM and [(123I]IPM was determined in healthy mice and the pH targeting efficacy in vivo of [(123I]IPM was evaluated in an anti-Fas monoclonal antibody (mAb apoptosis model. In addition a mouse RIF-1 tumor model was explored in which tumor pH was decreased from 7.0 to 6.5 by means of induction of hyperglycemia in combination with administration of meta-iodobenzylguanidine. RESULTS: Radiosynthesis resulted in 15-20% for iodo-bromo exchange and 50-60% yield for iodo-iodo exchange while in vitro experiments showed a pH-sensitive uptake for all tracers. Shelf-life stability and in vivo stability was excellent for all tracers. [(123I]IPMM and [(123I]IPM showed a moderately fast predominantly biliary clearance while a high retention was observed in blood. The biodistribution profile of [(123I]IPM was found to be most favorable in view of pH-specific imaging. [(123I]IPM showed a clear pH-related uptake pattern in the RIF-1 tumor model. CONCLUSION: Iodine-123 labeled malonic acid derivates such as [(123I]IPM show a clearly pH dependent uptake in tumor cells both in vitro and in vivo which allows to visualize regional acidosis. However, these compounds are not suitable for detection of apoptosis due to a poor acidosis effect.

Assessment of MODIS-derived indices (2001-2013) to drought across Taiwan's forests

Science.gov (United States)

Chang, Chung-Te; Wang, Hsueh-Ching; Huang, Cho-ying

2017-12-01

Tropical and subtropical ecosystems, the largest terrestrial carbon pools, are very susceptible to the variability of seasonal precipitation. However, the assessment of drought conditions in these regions is often overlooked due to the preconceived notion of the presence of high humidity. Drought indices derived from remotely sensed imagery have been commonly used for large-scale monitoring, but feasibility of drought assessment may vary across regions due to climate regimes and local biophysical conditions. Therefore, this study aims to evaluate the feasibility of 11 commonly used MODIS-derived vegetation/drought index in the forest regions of Taiwan through comparison with the station-based standardized precipitation index with a 3-month time scale (SPI3). The drought indices were further transformed (standardized anomaly, SA) to make them better delineate the spatiotemporal variations of drought conditions. The results showed that the Normalized Difference Infrared Index utilizing the near-infrared and shortwave infrared bands (NDII6) may be more superior to other indices in delineating drought patterns. Overall, the NDII6 SA-SPI3 pair yielded the highest correlation (mean r ± standard deviation = 0.31 ± 0.13) and was most significant in central and south Taiwan (r = 0.50-0.90) during the cold, dry season (January and April). This study illustrated that the NDII6 is suitable to delineate drought conditions in a relatively humid region. The results suggested the better performance of the NDII6 SA-SPI3 across the high climate gradient, especially in the regions with dramatic interannual amplifications of rainfall. This synthesis was conducted across a wide bioclimatic gradient, and the findings could be further generalized to a much broader geographical extent.

Energy densification of biomass-derived organic acids

Energy Technology Data Exchange (ETDEWEB)

Wheeler, M. Clayton; van Walsum, G. Peter; Schwartz, Thomas J.; van Heiningen, Adriaan

2013-01-29

A process for upgrading an organic acid includes neutralizing the organic acid to form a salt and thermally decomposing the resulting salt to form an energy densified product. In certain embodiments, the organic acid is levulinic acid. The process may further include upgrading the energy densified product by conversion to alcohol and subsequent dehydration.

Retention data of bile acids and their oxo derivatives in characterization of pharmacokinetic properties and in silico ADME modeling.

Science.gov (United States)

Trifunović, Jovana; Borčić, Vladan; Vukmirović, Saša; Kon, Svetlana Goločorbin; Mikov, Momir

2016-09-20

Information on ADME properties of examined bile acids and their oxo derivatives are scarce, although the interest for bile acids and their use in nanochemistry and macromolecular chemistry is increasing. The purpose of this research was to evaluate the lipophilicity, a crucial physicochemical parameter for describing ADME properties of selected bile acids and their oxo derivatives, and to compare two approaches: experimentally determined hydrophobicity parameters and calculated logP values. Commercially available bile acids - deoxycholic, chenodeoxycholic, hyodeoxycholic and ursodeoxycholic acid were used to synthesize oxo derivatives. Lipophilicity was evaluated in two solvent systems: toluene/ethanol and toluene/butanol. Retention parameters were acquired by normal-phase TLC. The correlations between calculated logP values obtained using five different software and experimentally determined hydrophobicity parameters (RM(0)(tol/eth), RM(0)(tol/but), b(tol/eth) and b(tol/but)) were examined. Correlation analysis confirmed significant dependence between experimental RM(0) values and software calculated parameters. Results suggest satisfactory intestinal absorption after oral administration for all of the examined compounds as well as low volumes of distribution, and high affinity for binding with plasma proteins. Penetration through blood-brain barrier and skin is not satisfactory. All of the examined compounds show high affinity for binding with G-protein coupled receptors and consequently inhibition of ionic channels. Results also suggest possible binding with nuclear receptors. Established lipophilicity testing model of studied compounds showed excellent predictive ability and might represent significant tool in development of relations between chromatographic behavior and ADME properties. Compounds 3α-hydroxy-7,12-dioxo-5β-cholanoic and 12α-hydroxy-3,7-dioxo-5β-cholanoic acid might be the most suitable candidates for further development studies (satisfactory

Synthesis of novel 3-cyclohexylpropanoic acid-derived nitrogen heterocyclic compounds and their evaluation for tuberculostatic activity.

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Gobis, Katarzyna; Foks, Henryk; Bojanowski, Krzysztof; Augustynowicz-Kopeć, Ewa; Napiórkowska, Agnieszka

2012-01-01

A series of novel 3-cyclohexylpropanoic acid derivatives and 3-cyclohexylpropanoic acid-derived nitrogen heterocyclic compounds (1-8) have been synthesized and evaluated for tuberculostatic activity. Compounds 1a, 1c, 1e and 1f bearing benzimidazole or benzimidazole-like systems showed the most potent tuberculostatic activity against Mycobacterium tuberculosis strains with MIC values ranging from 1.5 to 12.5μg/mL. More importantly 1a (6-chloro-2-(2-cyclohexylethyl)-4-nitro-1H-benzo[d]imidazole) and 1f (2-(2-cyclohexylethyl)-1H-imidazo[4,5-b]phenazine) appeared selective for M. tuberculosis as compared with eukaryotic cells (human fibroblasts), and other antimicrobial strains. These compounds may thus represent a novel, selective class of antitubercular agents. Additionally compound 1a stimulated type I collagen output by fibroblasts, in vitro. Copyright © 2011 Elsevier Ltd. All rights reserved.

Associations of Milk Consumption and Vitamin B2 and Β12 Derived from Milk with Fitness, Anthropometric and Biochemical Indices in Children. The Healthy Growth Study

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George Moschonis

2016-10-01

Full Text Available The benefits of dairy consumption seem to extend beyond its significant contribution to ensuring nutrient intake adequacy as indicated by the favourable associations with several health outcomes reported by different studies. The aims of the present study were to examine the associations of milk consumption with fitness, anthropometric and biochemical indices in children and further explore whether the observed associations are attributed to vitamins B2 and B12 derived from milk. A representative subsample of 600 children aged 9–13 years participating in the Healthy Growth Study was examined. Data were collected on children’s dietary intake, using 24 h recalls, as well as on fitness, anthropometric and biochemical indices. Regression analyses were performed for investigating the research hypothesis, adjusting for potential confounders and for B-vitamin status indices (i.e., plasma riboflavin, methylmalonic acid and total homocysteine concentrations, dietary calcium intake and plasma zinc concentrations that could possibly act as effect modifiers. Milk consumption was positively associated with the number of stages performed in the endurance run test (ERT (β = 0.10; p = 0.017 and negatively with body mass index (BMI (β = −0.10; p = 0.014, after adjusting for several potential confounders and effect modifiers. Dietary intakes of vitamin B2 and B12 derived from milk were also positively associated with the number of ERT stages (β = 0.10; p = 0.015 and β = 0.10; p = 0.014 respectively. In conclusion, higher intake of milk as well as vitamin B2 and B12 derived from milk were independently associated with higher cardiorespiratory fitness in Greek preadolescents. The key roles of these B-vitamins in substrate oxidation, energy production, haemoglobin synthesis and erythropoiesis could provide a basis for interpreting these associations. However, further research is needed to confirm this potential interpretation.

Differences in acid tolerance between Bifidobacterium breve BB8 and its acid-resistant derivative B. breve BB8dpH, revealed by RNA-sequencing and physiological analysis.

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Yang, Xu; Hang, Xiaomin; Tan, Jing; Yang, Hong

2015-06-01

Bifidobacteria are common inhabitants of the human gastrointestinal tract, and their application has increased dramatically in recent years due to their health-promoting effects. The ability of bifidobacteria to tolerate acidic environments is particularly important for their function as probiotics because they encounter such environments in food products and during passage through the gastrointestinal tract. In this study, we generated a derivative, Bifidobacterium breve BB8dpH, which displayed a stable, acid-resistant phenotype. To investigate the possible reasons for the higher acid tolerance of B. breve BB8dpH, as compared with its parental strain B. breve BB8, a combined transcriptome and physiological approach was used to characterize differences between the two strains. An analysis of the transcriptome by RNA-sequencing indicated that the expression of 121 genes was increased by more than 2-fold, while the expression of 146 genes was reduced more than 2-fold, in B. breve BB8dpH. Validation of the RNA-sequencing data using real-time quantitative PCR analysis demonstrated that the RNA-sequencing results were highly reliable. The comparison analysis, based on differentially expressed genes, suggested that the acid tolerance of B. breve BB8dpH was enhanced by regulating the expression of genes involved in carbohydrate transport and metabolism, energy production, synthesis of cell envelope components (peptidoglycan and exopolysaccharide), synthesis and transport of glutamate and glutamine, and histidine synthesis. Furthermore, an analysis of physiological data showed that B. breve BB8dpH displayed higher production of exopolysaccharide and lower H(+)-ATPase activity than B. breve BB8. The results presented here will improve our understanding of acid tolerance in bifidobacteria, and they will lead to the development of new strategies to enhance the acid tolerance of bifidobacterial strains. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synthesis and characterization of new polyamides derived from alanine and valine derivatives

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El-Faham Ayman

2012-11-01

Full Text Available Abstract Background Many efforts have been recently devoted to design, investigate and synthesize biocompatible, biodegradable polymers for applications in medicine for either the fabrication of biodegradable devices or as drug delivery systems. Many of them consist of condensation of polymers having incorporated peptide linkages susceptible to enzymatic cleavage. Polyamides (PAs containing α-amino acid residues such as L-leucine, L-alanine and L-phenylalanine have been reported as biodegradable materials. Furthermore, polyamides (PAs derived from C10 and C14 dicarboxylic acids and amide-diamines derived from 1,6-hexanediamine or 1,12-dodecanediamine and L-phenylalanine, L-valyl-L-phenylalanine or L-phenylalanyl-L-valine residues have been reported as biocompatible polymers. We have previously described the synthesis and thermal properties of a new type of polyamides-containing amino acids based on eight new symmetric meta-oriented protected diamines derived from coupling of amino acids namely; Fomc-glycine, Fmoc-alanine, Fomc-valine and Fomc-leucine with m-phenylene diamine or 2,6-diaminopyridine. Results revealed that incorporation of pyridine onto the polymeric backbone of all series decreases the thermal stability. Here we describe another family of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of the polymers. Results We report here the preparation of a new type of polyamides based on benzene dicarboxylic acid, pyridine dicarboxylic acid, and α-amino acid linked to benzidine and 4,4′-oxydianiline to study the effect of the dicarboxylic acid as well as the amino acids on the nature and thermal stability of polymers. The thermal properties of the polymers were evaluated by different techniques. Results revealed that structure-thermal property

In Silico Discovery of Novel Potent Antioxidants on the Basis of Pulvinic Acid and Coumarine Derivatives and Their Experimental Evaluation.

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Rok Martinčič

Full Text Available A pigment from the edible mushroom Xerocomus badius norbadione A, which is a natural derivative of pulvinic acid, was found to possess antioxidant properties. Since the pulvinic acid represents a novel antioxidant scaffold, several other derivatives were recently synthetized and evaluated experimentally, along with some structurally related coumarine derivatives. The obtained data formed the basis for the construction of several quantitative structure-activity and pharmacophore models, which were employed in the virtual screening experiments of compound libraries and for the prediction of their antioxidant activity, with the goal of discovering novel compounds possessing antioxidant properties. A final prioritization list of 21 novel compounds alongside 8 established antioxidant compounds was created for their experimental evaluation, consisting of the DPPH assay, 2-deoxyribose assay, β-carotene bleaching assay and the cellular antioxidant activity assay. Ten novel compounds from the tetronic acid and barbituric acid chemical classes displayed promising antioxidant activity in at least one of the used assays, that is comparable to or even better than some standard antioxidants. Compounds 5, 7 and 9 displayed good activity in all the assays, and were furthermore effective preventers of oxidative stress in human peripheral blood mononuclear cells, which are promising features for the potential therapeutic use of such compounds.

Effects of an ascorbic acid-derivative dentifrice in patients with gingivitis: a double-masked, randomized, controlled clinical trial.

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Shimabukuro, Yoshio; Nakayama, Yohei; Ogata, Yorimasa; Tamazawa, Kaoru; Shimauchi, Hidetoshi; Nishida, Tetsuya; Ito, Koichi; Chikazawa, Takashi; Kataoka, Shinsuke; Murakami, Shinya

2015-01-01

Reactive oxygen species might be associated with the onset and progression of gingival inflammation. The aim of this study is to investigate the effect of a dentifrice containing L-ascorbic acid 2-phosphate magnesium salt (APM), a long-acting ascorbic acid derivative with antioxidant properties, on gingival inflammation. The clinical effects of APM were investigated in a multicenter, randomized, parallel-group, controlled clinical trial comprising 300 individuals with gingivitis. Half of the participants were given an APM-containing dentifrice and half were given a control dentifrice. The primary outcome was the gingival index (GI) at 3 months. Secondary outcomes included gingival redness as an indicator of the degree of local gingival inflammation, gingival bleeding as a measure of the gingivitis severity index, and total antioxidant activity of the saliva. Under the intent-to-treat analysis, GI did not significantly differ between the groups (P = 0.12). However, under the per-protocol analysis, GI was significantly lower in the APM group (P = 0.01) than in the control group. In the APM group, gingival redness was significantly lower, and the difference from the baseline gingivitis severity index was significantly greater (P = 0.04 and P = 0.02, respectively). The total antioxidant activity of the saliva was significantly higher in the APM group (P = 0.03). The incidence of adverse events did not significantly differ between the groups (P > 0.15). These findings indicate that the regular application of an APM-containing dentifrice could reduce gingival inflammation.

Perfluoroalkyl Acids in Maternal Serum and Indices of Fetal Growth

DEFF Research Database (Denmark)

Bach, Cathrine C; Bech, Bodil H; Nohr, Ellen A

2015-01-01

BACKGROUND: Previous studies indicated an association between intrauterine exposure to perfluorooctane sulfonate (PFOS) or perfluorooctanoate (PFOA) and lower birth weight. However, these perfluoroalkyl acids (PFAAs) have to some extent been substituted by other compounds on which little is known...... was restricted to term births (n=1426). For PFOS, the birth weight estimates for the highest versus lowest quartile were -50 [95 % CI: -123; 23] g in all births and -62 [95 % CI: -126; 3] g in term births. For the other PFAAs, the direction of the associations was inconsistent, and no overall association...... with birth weight was apparent. No PFAAs were associated with birth length or head circumference at birth. CONCLUSIONS: Overall, we did not find strong or consistent associations between PFAAs and birth weight or other indices of fetal growth, though estimated mean birth weights were lower among those...

Determination of amino acid neurotransmitters in rat hippocampi by HPLC-UV using NBD-F as a derivative.

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Wu, Xiaomeng; Wang, Rui; Jiang, Qingqing; Wang, Shue; Yao, Yao; Shao, Lihua

2014-04-01

A simple, rapid and accurate high-performance liquid chromatography method with ultraviolet-visible detection was developed for the determination of five amino acid neurotransmitters - aspartate, glutamic acid, glycine, taurine and γ-aminobutyric acid - in rat hippocampi with pre-column derivatization with 4-fluoro-7-nitrobenzofurazan. Several conditions which influenced derivatization and separation, such as pH, temperature, acetonitrile percentage mobile phase and flow rate, were optimized to obtain a suitable protocol for amino acids quantification in samples. The separation of the five neurotransmitter derivatives was performed on a C18 column using a mobile phase consisting of phosphate buffer (0.02 mol/L, pH 6.0)-acetonitrile (84:16, v/v) at a flow rate of 1.0 mL/min with the column temperature at 30°C. The detection wavelength was 472 nm. Without gradient elution, the five neurotransmitter derivatives were completely separated within 15 min. The linear relation was good in the range from 0.50 to 500 µmol/L, and the correlation coefficients were ≥0.999. Intra-day precision was between 1.8 and 3.2%, and inter-day precision was between 2.4 and 4.7%. The limits of detection (signal-to-noise ratio 3) were from 0.02 to 0.15 µmol/L. The established method was used to determine amino acid neurotransmitters in rat hippocampi with satisfactory recoveries varying from 94.9 to 105.2%. Copyright © 2013 John Wiley & Sons, Ltd.

Amperometric titration of thorium and some lanthanoids in acetic-acid medium using two indicator electrodes

International Nuclear Information System (INIS)

Khadeev, V.A.; Gevorgyan, A.M.; Talipov, Sh.T.; Kostylev, V.S.

1979-01-01

The votammetric behaviour of nitriletrimethylphosphonic acid (NTMP) in the medium of anhydrous acetic acid with different backgrounds in the anode region of polarization of a platinum microdisk electrode, is studied. The optimal conditions are found for the amperometric titration with two indicator electrodes of thorium and same lanthanides by a NTMP solution in anhydrous acetic medium. The influence of foreign anions and cations on the results of titration by the NTPM solution in anhydrous acetic acid is studied. The selectivity of titration in anhydrous medium is higher than in aqueous

Phospholipid Fatty Acids as Physiological Indicators of Paracoccus denitrificans Encapsulated in Silica Sol-Gel Hydrogels

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Josef Trögl

2015-02-01

Full Text Available The phospholipid fatty acid (PLFA content was determined in samples of Paracoccus denitrificans encapsulated in silica hydrogel films prepared from prepolymerized tetramethoxysilane (TMOS. Immediately after encapsulation the total PLFA concentration was linearly proportional to the optical density (600 nm of the input microbial suspension (R2 = 0.99. After 7 days this relationship remained linear, but with significantly decreased slope, indicating a higher extinction of bacteria in suspensions of input concentration 108 cells/mL and higher. trans-Fatty acids, indicators of cytoplasmatic membrane disturbances, were below the detection limit. The cy/pre ratio (i.e., ratio of cyclopropylated fatty acids (cy17:0 + cy19:0 to their metabolic precursors (16:1ω7 + 18:1ω7, an indicator of the transition of the culture to a stationary growth-phase, decreased depending on co-immobilization of nutrients in the order phosphate buffer > mineral medium > Luria Broth rich medium. The ratio, too, was logarithmically proportional to cell concentration. These results confirm the applicability of total PLFA as an indicator for the determination of living biomass and cy/pre ratio for determination of nutrient limitation of microorganisms encapsulated in sol-gel matrices. This may be of interest for monitoring of sol-gel encapsulated bacteria proposed as optical recognition elements in biosensor construction, as well as other biotechnological applications.

Anthocyanins and phenolic acids from a wild blueberry (Vaccinium angustifolium) powder counteract lipid accumulation in THP-1-derived macrophages

DEFF Research Database (Denmark)

Del Bo', Cristian; Cao, Yi; Roursgaard, Martin

2016-01-01

PURPOSE: Blueberries are a rich source of anthocyanins (ACNs) and phenolic acids (PA), which are hypothesized to protect against development of atherosclerosis. The present study examined the effect of an ACN- and PA-rich fractions, obtained from a wild blueberry powder, on the capacity...... to counteract lipid accumulation in macrophages derived from monocytic THP-1 cells. In addition, we tested the capacity of pure ACNs and their metabolites to alter lipid accumulation. METHODS: THP-1-derived macrophages were incubated with fatty acids (500 μM oleic/palmitic acid, 2:1 ratio) and different...... concentrations (from 0.05 to 10 μg mL(-1)) of ACN- and PA-rich fractions, pure ACN standards (malvidin, delphinidin and cyanidin 3-glucoside), and metabolites (syringic, gallic and protocatechuic acids). Lipid accumulation was quantified with the fluorescent dye Nile red. RESULTS: Lipid accumulation was reduced...

Isocyanides Derived from α,α-Disubstituted Amino Acids: Synthesis and Antifouling Activity Assessment.

Science.gov (United States)

Inoue, Yuki; Takashima, Shuhei; Nogata, Yasuyuki; Yoshimura, Erina; Chiba, Kazuhiro; Kitano, Yoshikazu

2018-03-01

Herein, we contribute to the development of environmentally friendly antifoulants by synthesizing eighteen isocyanides derived from α,α-disubstituted amino acids and evaluating their antifouling activity/toxicity against the cypris larvae of the Balanus amphitrite barnacle. Almost all isocyanides showed good antifouling activity without significant toxicity and exhibited EC 50 values of 0.07 - 7.30 μg/mL after 120-h exposure. The lowest EC 50 values were observed for valine-, methionine-, and phenylalanine-derived isocyanides, which achieved > 95% cypris larvae settlement inhibition at concentrations of less than 30 μg/mL without exhibiting significant toxicity. Thus, the prepared isocyanides should be useful for further research focused on the development of environmentally friendly antifouling agents. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

[Synthesis and physico-chemical characterisation of some new derivatives of rutoside and clofibric acid].

Science.gov (United States)

Lupaşcu, D; Profire, Lenuţa; Dănilă, Gh

2006-01-01

Fibrates are drugs with efficacy in reducing blood cholesterol levels and especially, triglyceride plasma levels. Unfortunately, fibrates have a poor water-solubility and showed some adverse reactions at long treatment. The objective of this study was to obtain some new clofibric acid derivatives with rutin; some of these compounds contain a guanidine moiety, known as effective at cardiovascular level. All the compounds are soluble in water.

Magnetic nanoparticle supported phosphotungstic acid: An efficient catalyst for the synthesis of xanthene derivatives

Science.gov (United States)

Patel, Nipun; Katheriya, Deepak; Dadhania, Harsh; Dadhania, Abhishek

2018-05-01

Magnetic nanoparticle supported phosphotungstic acid (Fe3O4@SiO2-HPW) was applied as a highly efficient catalyst for the synthesis of 14H-dibenzoxanthene derivatives via condensation reaction of 2-naphthol and aryl aldehydes. The catalyst was found highly efficient for the synthesis of xanthene derivatives under solvent free condition. The catalyst showed high activity and stability during the reaction and provided excellent yield of the corresponding products in short reaction time. All the synthesized compounds were characterized through FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. Furthermore, the catalyst is magnetically recoverable and can be reused several times without significant loss of its catalytic activity.

Myrsinoic A acid and its derivative: in vitro inhibitors of photosynthesis

International Nuclear Information System (INIS)

Burger, Marcela Carmen de M.; Oliveira, Gracielle S. de; Menezes, Antonio Carlos S.; Vieira, Paulo Cezar; Silva, Maria Fatima das G.F. da; Veiga, Thiago A.M.

2012-01-01

Myrsinoic A acid, isolated from Myrsine cuneifolia and its hydrogenated derivative had their effect on photosynthesis tested. The compounds inhibited the electron flow (basal, phosphorylating and uncoupled) from water to methyl viologen; therefore, they act as Hill reaction inhibitors in spinach thylakoids. They inhibited partial reactions of PSII electron flow from water to 2,5-dichloro-1,4-benzoquinone, from water to sodium silicomolybdate, and partially electron flow from diphenylcarbazide to 2,6-dichloroindophenol. Their inhibition sites were at the donor and acceptor sides of PSII, between P 680 and Q A . Chlorophyll α fluorescence measurements confirmed the behavior of the compounds (pool of quinones). (author)

Preferential oxidation of linolenic acid compared to linoleic acid in the liver of catfish (Heteropneustes fossilis and Clarias batrachus)

International Nuclear Information System (INIS)

Bandyopadhyay, G.K.; Dutta, J.; Ghosh, S.

1982-01-01

The fate of [1(- 14 C] linoleic acid and [1( 14 C] linolenic acid in the liver slices and also in the liver tissues of live carnivorous catfish, Heteropneustes fossilis and Clarias batrachus, was studied. Incorporation of the fatty acids into different lipid classes in the live fish differed greatly from the tissue slices, indicating certain physiological control operative in vivo. The extent of desaturation and chain elongation of linoleic and linolenic acids into long-chain polyunsaturated fatty acids was low. Linolenic acid was oxidized (thus labeling the saturated fatty acid with liberated 14 C-acetyl-CoA) in preference to linoleic acid, and this oxidation also seemed to be under physiological control since both of the fatty acids were poorly oxidized in the tissue slices and in the killed fish. These fish can therefore recognize the difference in the acyl chain structures of linoleate and linolenate. The higher oxidation of linolenic acid and poor capacity for its conversion to longer chain, highly unsaturated derivatives indicates a higher demand for the dietary supply of these essential fatty acids in these two species

Octulosonic acid derivatives from Roman chamomile (Chamaemelum nobile) with activities against inflammation and metabolic disorder.

Science.gov (United States)

Zhao, Jianping; Khan, Shabana I; Wang, Mei; Vasquez, Yelkaira; Yang, Min Hye; Avula, Bharathi; Wang, Yan-Hong; Avonto, Cristina; Smillie, Troy J; Khan, Ikhlas A

2014-03-28

Six new octulosonic acid derivatives (1-6) were isolated from the flower heads of Roman chamomile (Chamaemelum nobile). Their structures were elucidated by means of spectroscopic interpretation. The biological activity of the isolated compounds was evaluated toward multiple targets related to inflammation and metabolic disorder such as NAG-1, NF-κB, iNOS, ROS, PPARα, PPARγ, and LXR. Similar to the action of NSAIDs, all the six compounds (1-6) increased NAG-1 activity 2-3-fold. They also decreased cellular oxidative stress by inhibiting ROS generation. Compounds 3, 5, and 6 activated PPARγ 1.6-2.1-fold, while PPARα was activated 1.4-fold by compounds 5 and 6 only. None of the compounds showed significant activity against iNOS or NF-κB. This is the first report of biological activity of octulosonic acid derivatives toward multiple pathways related to inflammation and metabolic disorder. The reported anti-inflammatory, hypoglycemic, antiedemic, and antioxidant activities of Roman chamomile could be partly explained as due to the presence of these constituents.

Biological activity of some novel synthesized 2-(4-methylbenzenesulphonamidopentanedioic acid bis amide derivatives: In vitro and in vivo antineoplastic activity

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Satyajit Dutta

2014-12-01

Full Text Available In the present work few novel 2-(4-methylbenzenesulphonamidopentanedioic acid bis amide derivatives and the basic compound 2-(4-methylphenylsulfonamidopentanedioic acid have been synthesized, characterized and screened for their possible antineoplastic activity both in vitro and in vivo. The in vitro activity was performed against five human cell lines like human breast cancer (MCF-7, leukemia (K-562, ovarian cancer (OVACAR-3, human colon adenocarcinoma (HT-29 and Human kidney carcinoma (A-498. The in vivo activity was performed in female swiss albino mice against Ehrlich ascites carcinoma (EAC. Among the synthesized compounds, ureide, anilide, p-nitoanilide and o-bromoanilide derivatives of 2-(4-methyl benzene sulphonyl-pentanedioic acid bis amides showed encouraging activity in both the in vitro and in vivo compared to other compounds.

Some aromatic hydrazone derivatives as inhibitors for the corrosion of C-steel in phosphoric acid solution.

Science.gov (United States)

Fouda, Abd El-Aziz S; Al-Sarawy, Ahmed A; Radwan, Mohamed S

2006-01-01

The effect of furfural benzoylhydrazone and its derivatives (I-VII) as corrosion inhibitors for C-steel in 1M phosphoric acid solution has been studied by weight-loss and galvanostatic polarization techniques. A significant decrease in the corrosion rate of C-steel was observed in the presence of the investigated inhibitors. This study revealed that, the inhibition efficiency increases with increasing the inhibitor concentration, and the addition of iodide ions enhances it to a considerable extent. The effect of temperature on the inhibition efficiency of these compounds was studied using weight-loss method. Activation energy (E(a)*) and other thermodynamic parameters for the corrosion process were calculated and discussed. The galvanostatic polarization data indicated that, the inhibitors were of mixed-type, but the cathode is more polarized than the anode. The adsorption of these compounds on C-steel surface has been found to obey Frumkin's adsorption isotherm. The mechanism of inhibition was discussed in the light of the chemical structure of the undertaken inhibitors.

Novel selective thiazoleacetic acids as CRTH2 antagonists developed from in silico derived hits. Part 1

DEFF Research Database (Denmark)

Rist, Oystein; Grimstrup, Marie; Receveur, Jean-Marie

2009-01-01

Structure-activity relationships of three related series of 4-phenylthiazol-5-ylacetic acids, derived from two hits emanating from a focused library obtained by in silico screening, have been explored as CRTH2 (chemoattractant receptor-homologous molecule expressed on Th2 cells) antagonists....... Several compounds with double digit nanomolar binding affinity and full antagonistic efficacy for human CRTH2 receptor were obtained in all subclasses. The most potent compound was [2-(4-chloro-benzyl)-4-(4-phenoxy-phenyl)-thiazol-5-yl]acetic acid having an binding affinity of 3.7nM and functional...

Radical-Scavenging Activity of Thiols, Thiobarbituric Acid Derivatives and Phenolic Antioxidants Determined Using the Induction Period Method for Radical Polymerization of Methyl Methacrylate

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Seiichiro Fujisawa

2012-04-01

Full Text Available The radical-scavenging activities of two thiols, eight (thiobarbituric acid derivatives and six chain-breaking phenolic antioxidants were investigated using the induction period method for polymerization of methyl methacrylate (MMA initiated by thermal decomposition of 2,2’-azobisisobutyronitrile (AIBN and monitored by differential scanning calorimetry (DSC. The induction period (IP for the thiols 2-mercaptoethanol (ME and 2-mercapto-1-methylimidazole (MMI was about half that for phenolic antioxidants. Except for the potent inhibitor 5,5-dimethyl-2-thiobarbituric acid (3, the IP for thiobarbituric acid derivatives was about one tenth of that for phenolic antioxidants. The IP for 1,3,5-trimethyl-2-thiobarbituric acid (1 and 5-allyl-1, 3-dimethyl-2-thiobarbituric acid (7 was less than that of the control, possibly due to inhibition by a small amount of atmospheric oxygen in the DSC container. The ratio of the chain inhibition to that of chain propagation (CI/CP for the thiols and thiobarbituric acid compounds except for 1, 3 and 7 was about 10 times greater or greater than that for phenolic compounds. A kinetic chain length (KCL about 10% greater than that of the control was observed for 1, suggesting that 1 had chain transfer reactivity in the polymerization of MMA. The average molecular weight of polymers formed from thiobarbituric acid derivatives is discussed.

Identification of new derivatives of 2-S-glutathionylcaftaric acid in aged white wines by HPLC-DAD-ESI-MS(n).

Science.gov (United States)

Cejudo-Bastante, María Jesús; Pérez-Coello, María Soledad; Hermosín-Gutiérrez, Isidro

2010-11-10

Glutathione, a natural occurring antioxidant, is a thiol-containing peptide present in grape must and wine. It is able to regenerate the o-diphenol group of enzymatically oxidized trans-caftaric acid, giving rise to 2-S-glutathionyl-trans-caftaric acid (also known as grape reaction product, GRP) and thus inhibiting the browning of wine. The amount of GRP present in a wine provides information on the oxidation history of the wine over its elaboration and aging. GRP has been proved to suffer hydrolysis in model solutions and wines. To know the actual content of glutathione involved in white wine browning inhibition as GRP, the GRP-derived products have been studied in 1-year-aged white wines by HPLC-DAD-ESI-MS(n). Online UV-vis spectra and pseudomolecular ions [(M + H)(+)] obtained by LC-MS supported the formation of some of the expected GRP hydrolysis products, mainly 2-S-glutathionyl-trans-caffeic acid (trans-GSCf), together with minor 2-S-(cysteinylglycyl)-trans-caftaric acid, 2-S-(γ-glutamylcysteinyl)-trans-caftaric acid, and 2-S-cysteinyl-trans-caftaric acid. On the basis of UV-vis and LC-MS(2) spectra, new GRP derivatives in aged white wines have been tentatively characterized for the first time as three monoethyl esters of GRP (GRP-Et) and also the cis isomers of GRP, GSCf, and some of the GRP-Et.

Immunotoxic effects of oil sands-derived naphthenic acids to rainbow trout

Energy Technology Data Exchange (ETDEWEB)

MacDonald, Gillian Z.; Hogan, Natacha S. [Canadian Rivers Institute, Department of Biology, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI (Canada); Koellner, Bernd [Friedrich Loeffler Institute, Federal Research Institute of Animal Health, Institute of Immunology, Greifswald (Germany); Thorpe, Karen L.; Phalen, Laura J. [Canadian Rivers Institute, Department of Biology, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI (Canada); Wagner, Brian D. [Department of Chemistry, University of Prince Edward Island, Charlottetown (Canada); Heuvel, Michael R. van den, E-mail: mheuvel@upei.ca [Canadian Rivers Institute, Department of Biology, University of Prince Edward Island, 550 University Avenue, Charlottetown, PEI (Canada)

2013-01-15

Naphthenic acids are the major organic constituents in waters impacted by oil sands. To investigate their immunotoxicity, rainbow trout (Oncorhynchus mykiss) were injected with naphthenic acids extracted from aged oil sands tailings water. In two experiments, rainbow trout were injected intraperitoneally with 0, 10, or 100 mg/kg of naphthenic acids, and sampled after 5 or 21 d. Half of the fish from the 21 d exposure were co-exposed to inactivated Aeromonas salmonicida (A.s.) to induce an immune response. A positive control experiment was conducted using an intraperitoneal injection of 100 mg/kg of benzo[a]pyrene, a known immune suppressing compound. T-lymphocytes, B-lymphocytes, thrombocytes, and myeloid cells were counted in blood and lymphatic tissue using flow cytometry. In the 5 d exposure, there was a reduction in blood leucocytes and spleen thrombocytes at the 100 mg/kg dose. However, at 21 d, leucocyte populations showed no effects of exposure with the exception that spleen thrombocyte populations increase at the 100 mg/kg dose. In the 21 d exposure, B- and T-lymphocytes in blood showed a significant Dose Multiplication-Sign A.s. interaction, indicating stimulated blood cell proliferation due to naphthenic acids alone as well as due to A.s. Naphthenic acid injections did not result in elevated bile fluorescent metabolites or elevated hepatic EROD activity. In contrast to naphthenic acids exposures, as similar dose of benzo[a]pyrene caused a significant decrease in B- and T-lymphocyte absolute counts in blood and relative B-lymphocyte counts in spleen. Results suggest that the naphthenic acids may act via a generally toxic mechanism rather than by specific toxic effects on immune cells.

Immunotoxic effects of oil sands-derived naphthenic acids to rainbow trout

International Nuclear Information System (INIS)

MacDonald, Gillian Z.; Hogan, Natacha S.; Köllner, Bernd; Thorpe, Karen L.; Phalen, Laura J.; Wagner, Brian D.; Heuvel, Michael R. van den

2013-01-01

Naphthenic acids are the major organic constituents in waters impacted by oil sands. To investigate their immunotoxicity, rainbow trout (Oncorhynchus mykiss) were injected with naphthenic acids extracted from aged oil sands tailings water. In two experiments, rainbow trout were injected intraperitoneally with 0, 10, or 100 mg/kg of naphthenic acids, and sampled after 5 or 21 d. Half of the fish from the 21 d exposure were co-exposed to inactivated Aeromonas salmonicida (A.s.) to induce an immune response. A positive control experiment was conducted using an intraperitoneal injection of 100 mg/kg of benzo[a]pyrene, a known immune suppressing compound. T-lymphocytes, B-lymphocytes, thrombocytes, and myeloid cells were counted in blood and lymphatic tissue using flow cytometry. In the 5 d exposure, there was a reduction in blood leucocytes and spleen thrombocytes at the 100 mg/kg dose. However, at 21 d, leucocyte populations showed no effects of exposure with the exception that spleen thrombocyte populations increase at the 100 mg/kg dose. In the 21 d exposure, B- and T-lymphocytes in blood showed a significant Dose × A.s. interaction, indicating stimulated blood cell proliferation due to naphthenic acids alone as well as due to A.s. Naphthenic acid injections did not result in elevated bile fluorescent metabolites or elevated hepatic EROD activity. In contrast to naphthenic acids exposures, as similar dose of benzo[a]pyrene caused a significant decrease in B- and T-lymphocyte absolute counts in blood and relative B-lymphocyte counts in spleen. Results suggest that the naphthenic acids may act via a generally toxic mechanism rather than by specific toxic effects on immune cells.

Preparation and structural characterisation of novel and versatile amphiphilic octenyl succinic anhydride-modified hyaluronic acid derivatives

DEFF Research Database (Denmark)

Eenschooten, Corinne Diane; Guillaumie, Fanny; Kontogeorgis, Georgios

2010-01-01

and structurally characterised by Fourier transform-infrared spectroscopy and proton nuclear magnetic resonance spectroscopy (1H NMR). The influence of four reaction parameters on the DS of the derivatives was studied by means of an experimental design. The results showed that the OSA/HA molar ratio, the buffer......The purpose of the present study was to prepare amphiphilic hyaluronic acid (HA) derivatives and to study the influence of a selection of reaction parameters on the degree of substitution (DS) of the derivatives. Octenyl succinic anhydride (OSA)–modified HA (OSA–HA) derivatives were prepared...... (NaHCO3) concentration and their interaction had the largest influence while the HA concentration and the reaction time only had a negligible effect. According to 1H NMR the maximum DS achieved within the experimental conditions tested was 43% per disaccharide unit. Moreover optimal reaction...

Efficient non-sterilized fermentation of biomass-derived xylose to lactic acid by a thermotolerant Bacillus coagulans NL01.

Science.gov (United States)

Ouyang, Jia; Cai, Cong; Chen, Hai; Jiang, Ting; Zheng, Zhaojuan

2012-12-01

Xylose is the major pentose and the second most abundant sugar in lignocellulosic feedstock. Its efficient utilization is regarded as a technical barrier to the commercial production of bulk chemicals from lignocellulosic biomass. This work aimed at evaluating the lactic acid production from the biomass-derived xylose using non-sterilized fermentation by Bacillus coagulans NL01. A maximum lactic acid concentration of about 75 g/L was achieved from xylose of 100 g/L after 72 h batch fermentation. Acetic acid and levulinic acid were identified as important inhibitors in xylose fermentation, which markedly reduced lactic acid productivity at 15 and 1.0 g/L, respectively. But low concentrations of formic acid (coagulans NL01, the same preference for glucose, xylose, and arabinose was observed and18.2 g/L lactic acid was obtained after 48 h fermentation. These results proved that B. coagulans NL01 was potentially well-suited for producing lactic acid from underutilized xylose-rich prehydrolysates.

Prospects of an alternative treatment against Trypanosoma cruzi based on abietic acid derivatives show promising results in Balb/c mouse model.

Science.gov (United States)

Olmo, F; Guardia, J J; Marin, C; Messouri, I; Rosales, M J; Urbanová, K; Chayboun, I; Chahboun, R; Alvarez-Manzaneda, E J; Sánchez-Moreno, M

2015-01-07

Chagas disease, caused by the protozoa parasite Trypanosoma cruzi, is an example of extended parasitaemia with unmet medical needs. Current treatments based on old-featured benznidazole (Bz) and nifurtimox are expensive and do not fulfil the criteria of effectiveness, and a lack of toxicity devoid to modern drugs. In this work, a group of abietic acid derivatives that are chemically stable and well characterised were introduced as candidates for the treatment of Chagas disease. In vitro and in vivo assays were performed in order to test the effectiveness of these compounds. Finally, those which showed the best activity underwent additional studies in order to elucidate the possible mechanism of action. In vitro results indicated that some compounds have low toxicity (i.e. >150 μM, against Vero cell) combined with high efficacy (i.e. <20 μM) against some forms of T. cruzi. Further in vivo studies on mice models confirmed the expectations of improvements in infected mice. In vivo tests on the acute phase gave parasitaemia inhibition values higher those of Bz, and a remarkable decrease in the reactivation of parasitaemia was found in the chronic phase after immunosuppression of the mice treated with one of the compounds. The morphological alterations found in treated parasites with our derivatives confirmed extensive damage; energetic metabolism disturbances were also registered by (1)H NMR. The demonstrated in vivo activity and low toxicity, together with the use of affordable starting products and the lack of synthetic complexity, put these abietic acid derivatives in a remarkable position toward the development of an anti-Chagasic agent. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Folic acid derivatives for PET imaging and therapy addressing folate receptor positive tumors

Energy Technology Data Exchange (ETDEWEB)

Schieferstein, Hanno

2013-07-01

conducted. The synthesis of the folate-boron clusters was straightforward. At first, a linker molecule based on maleic acid was synthesized, which was coupled to the boron cluster via Michael Addition of a thiol and alkene and subsequently coupled to the targeting moiety using CuAAC. The new conjugates of folate and boron clusters led to a significant increase of boron concentration in the cell of about 5-times compared to currently used and approved boron pharmaceuticals. Moreover, azido-folate derivatives were coupled to macromolecular carrier systems (pHPMA), which showed an enhanced and specific accumulation at target sites (up to 2.5-times) during in vivo experiments. A specific blockade could be observed up to 30% indicating an efficient targeting effect. A new kind of nanoparticles consisting of a PDLLA core and p((HPMA)-b-(LMA)) as surfactants were developed and successfully radiolabeled via {sup 18}F-click chemistry in good RCYs of 8±3%. The nanoparticles were obtained via the miniemulsion technique in combination with solvent evaporation. The {sup 18}F-labeled nanoparticles were applied to in vivo testing using a mouse model. PET imaging showed a ''mixed'' biodistribution of low molecular weight as well as high molecular weight systems, indicating a partial loss of the {sup 18}F-labeled surfactant. In conclusion, the presented work successfully utilized the FR-targeting concept in both, the diagnostic field (PET imaging) and for therapeutic approaches (BNCT, drug delivery systems). As a result, the high potential of FR-targeting in oncological applications has been shown and was confirmed by small animal PET imaging.

Folic acid derivatives for PET imaging and therapy addressing folate receptor positive tumors

International Nuclear Information System (INIS)

Schieferstein, Hanno

2013-01-01

the folate-boron clusters was straightforward. At first, a linker molecule based on maleic acid was synthesized, which was coupled to the boron cluster via Michael Addition of a thiol and alkene and subsequently coupled to the targeting moiety using CuAAC. The new conjugates of folate and boron clusters led to a significant increase of boron concentration in the cell of about 5-times compared to currently used and approved boron pharmaceuticals. Moreover, azido-folate derivatives were coupled to macromolecular carrier systems (pHPMA), which showed an enhanced and specific accumulation at target sites (up to 2.5-times) during in vivo experiments. A specific blockade could be observed up to 30% indicating an efficient targeting effect. A new kind of nanoparticles consisting of a PDLLA core and p((HPMA)-b-(LMA)) as surfactants were developed and successfully radiolabeled via 18 F-click chemistry in good RCYs of 8±3%. The nanoparticles were obtained via the miniemulsion technique in combination with solvent evaporation. The 18 F-labeled nanoparticles were applied to in vivo testing using a mouse model. PET imaging showed a ''mixed'' biodistribution of low molecular weight as well as high molecular weight systems, indicating a partial loss of the 18 F-labeled surfactant. In conclusion, the presented work successfully utilized the FR-targeting concept in both, the diagnostic field (PET imaging) and for therapeutic approaches (BNCT, drug delivery systems). As a result, the high potential of FR-targeting in oncological applications has been shown and was confirmed by small animal PET imaging.

Triterpene Acids from Frankincense and Semi-Synthetic Derivatives That Inhibit 5-Lipoxygenase and Cathepsin G

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Andreas Koeberle

2018-02-01

Full Text Available Age-related diseases, such as osteoarthritis, Alzheimer’s disease, diabetes, and cardiovascular disease, are often associated with chronic unresolved inflammation. Neutrophils play central roles in this process by releasing tissue-degenerative proteases, such as cathepsin G, as well as pro-inflammatory leukotrienes produced by the 5-lipoxygenase (5-LO pathway. Boswellic acids (BAs are pentacyclic triterpene acids contained in the gum resin of the anti-inflammatory remedy frankincense that target cathepsin G and 5-LO in neutrophils, and might thus represent suitable leads for intervention with age-associated diseases that have a chronic inflammatory component. Here, we investigated whether, in addition to BAs, other triterpene acids from frankincense interfere with 5-LO and cathepsin G. We provide a comprehensive analysis of 17 natural tetra- or pentacyclic triterpene acids for suppression of 5-LO product synthesis in human neutrophils. These triterpene acids were also investigated for their direct interference with 5-LO and cathepsin G in cell-free assays. Furthermore, our studies were expanded to 10 semi-synthetic BA derivatives. Our data reveal that besides BAs, several tetra- and pentacyclic triterpene acids are effective or even superior inhibitors of 5-LO product formation in human neutrophils, and in parallel, inhibit cathepsin G. Their beneficial target profile may qualify triterpene acids as anti-inflammatory natural products and pharmacological leads for intervention with diseases related to aging.

Triterpene Acids from Frankincense and Semi-Synthetic Derivatives That Inhibit 5-Lipoxygenase and Cathepsin G.

Science.gov (United States)

Koeberle, Andreas; Henkel, Arne; Verhoff, Moritz; Tausch, Lars; König, Stefanie; Fischer, Dagmar; Kather, Nicole; Seitz, Stefanie; Paul, Michael; Jauch, Johann; Werz, Oliver

2018-02-24

Age-related diseases, such as osteoarthritis, Alzheimer's disease, diabetes, and cardiovascular disease, are often associated with chronic unresolved inflammation. Neutrophils play central roles in this process by releasing tissue-degenerative proteases, such as cathepsin G, as well as pro-inflammatory leukotrienes produced by the 5-lipoxygenase (5-LO) pathway. Boswellic acids (BAs) are pentacyclic triterpene acids contained in the gum resin of the anti-inflammatory remedy frankincense that target cathepsin G and 5-LO in neutrophils, and might thus represent suitable leads for intervention with age-associated diseases that have a chronic inflammatory component. Here, we investigated whether, in addition to BAs, other triterpene acids from frankincense interfere with 5-LO and cathepsin G. We provide a comprehensive analysis of 17 natural tetra- or pentacyclic triterpene acids for suppression of 5-LO product synthesis in human neutrophils. These triterpene acids were also investigated for their direct interference with 5-LO and cathepsin G in cell-free assays. Furthermore, our studies were expanded to 10 semi-synthetic BA derivatives. Our data reveal that besides BAs, several tetra- and pentacyclic triterpene acids are effective or even superior inhibitors of 5-LO product formation in human neutrophils, and in parallel, inhibit cathepsin G. Their beneficial target profile may qualify triterpene acids as anti-inflammatory natural products and pharmacological leads for intervention with diseases related to aging.

An Ursolic Acid Derived Small Molecule Triggers Cancer Cell Death through Hyperstimulation of Macropinocytosis.

Science.gov (United States)

Sun, Lin; Li, Bin; Su, Xiaohui; Chen, Ge; Li, Yaqin; Yu, Linqian; Li, Li; Wei, Wanguo

2017-08-10

Macropinocytosis is a transient endocytosis that internalizes extracellular fluid and particles into vacuoles. Recent studies suggest that hyperstimulation of macropinocytosis can induce a novel nonapoptotic cell death, methuosis. In this report, we describe the identification of an ursolic acid derived small molecule (compound 17), which induces cancer cell death through hyperstimulation of macropinocytosis. 17 causes the accumulation of vacuoles derived from macropinosomes based on transmission electron microscopy, time-lapse microscopy, and labeling with extracellular fluid phase tracers. The vacuoles induced by 17 separate from other cytoplasmic compartments but acquire some characteristics of late endosomes and lysosomes. Inhibiting hyperstimulation of macropinocytosis with the specific inhibitor amiloride blocks cell death, implicating that 17 leads to cell death via macropinocytosis, which is coincident with methuosis. Our results uncovered a novel cell death pathway involved in the activity of 17, which may provide a basis for further development of natural-product-derived scaffolds for drugs that trigger cancer cell death by methuosis.

Dehydroacetic Acid Derivatives Bearing Amide or Urea Moieties as Effective Anion Receptors.

Science.gov (United States)

Bregović, Nikola; Cindro, Nikola; Bertoša, Branimir; Barišić, Dajana; Frkanec, Leo; Užarević, Krunoslav; Tomišić, Vladislav

2017-08-01

Derivatives of dehydroacetic acid comprising amide or urea subunits have been synthesized and their anion-binding properties investigated. Among a series of halides and oxyanions, the studied compounds selectively bind acetate and dihydrogen phosphate in acetonitrile and dimethyl sulfoxide. The corresponding complexation processes were characterized by means of 1 H NMR titrations, which revealed a 1:1 complex stoichiometry in most cases, with the exception of dihydrogen phosphate, which formed 2:1 (anion/ligand) complexes in acetonitrile. The complex stability constants were determined and are discussed with respect to the structural properties of the receptors, the hydrogen-bond-forming potential of the anions, and the characteristics of the solvents used. Based on the spectroscopic data and results of Monte Carlo simulations, the amide or urea groups were affirmed as the primary binding sites in all cases. The results of the computational methods indicate that an array of both inter- and intramolecular hydrogen bonds can form in the studied systems, and these were shown to play an important role in defining the overall stability of the complexes. Solubility measurements were carried out in both solvents and the thermodynamics of transfer from acetonitrile to dimethyl sulfoxide were characterized on a quantitative level. This has afforded a detailed insight into the impact of the medium on the complexation reactions. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pre-conceptual-schema-based patterns for deriving key performance indicators from strategic objectives

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Carlos Mario Zapata Jaramillo

2017-05-01

Full Text Available Performance measurement is crucial for achieving business success. Moreover, such success is also related to the fulfillment of the organizational strategic objectives. Hence, an adequate determination of relevant performance indicators—or key performance indicators (KPIs—and their relationships to organizational objectives is needed. Even though several approaches for treating KPIs and objective-KPI relationships have been proposed, they exhibit some drawbacks associated with the lack of reusability and traceability. We attempt to fill this gap by proposing a set of patterns based on pre-conceptual schemas for supporting the systematic derivation of KPIs and their relationships to organizational objectives. In this way, the proposed patterns guarantee a reusable and traceable derivation process of a set of candidate KPIs from organizational strategic objectives. Lastly, we provide a lab study in order to illustrate the usefulness of this proposal.

Gamma-aminobutyric acid, a potential tumor suppressor for small airway-derived lung adenocarcinoma.

Science.gov (United States)

Schuller, Hildegard M; Al-Wadei, Hussein A N; Majidi, Mourad

2008-10-01

Pulmonary adenocarcinoma (PAC) is the leading type of lung cancer in smokers and non-smokers that arises in most cases from small airway epithelial cells. PAC has a high mortality due to its aggressive behavior and resistance to cancer therapeutics. We have shown previously that the proliferation of human PAC cells NCI-H322 and immortalized human small airway epithelial cells HPL1D is stimulated by cyclic adenosine monophosphate (cAMP)/protein kinase A-dependent phosphorylation of cyclic adenosine monophosphate response element-binding (CREB) protein and transactivation of the epidermal growth factor receptor and that this pathway is activated by beta-1-adrenoreceptors (beta(1)-ARs) and the non-genomic estrogen receptor beta. Our current in vitro studies with HPL1D and NCI-H322 cells showed that signaling via the gamma-amino butyric acid receptor (GABA(B)R) strongly inhibited base level and isoproterenol-induced cAMP, p-CREB, cyclic adenosine monophosphate response element-luciferase activity and p-extracellular regulated kinase-1 (ERK1)/2 and effectively blocked DNA synthesis and cell migration. The inhibitory effects of gamma-amino butyric acid (GABA) were disinhibited by the GABA(B)R antagonist CGP-35348 or GABA(B)R knockdown. Immunohistochemical investigation of hamster lungs showed significant underexpression of GABA in animals with small airway-derived PACs induced by the nicotine-derived carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). These findings suggest that GABA may have tumor suppressor function in small airway epithelia and the PACs derived from them and that downregulation of GABA by NNK may contribute to the development of this cancer in smokers. Our findings suggest that marker-guided treatment with GABA or a GABA(B)R agonist of individuals with downregulated pulmonary GABA may provide a novel targeted approach for the prevention of PAC in smokers.

Lewis base activation of Lewis acids: catalytic, enantioselective addition of glycolate-derived silyl ketene acetals to aldehydes.

Science.gov (United States)

Denmark, Scott E; Chung, Won-Jin

2008-06-20

A catalytic system involving silicon tetrachloride and a chiral, Lewis basic bisphosphoramide catalyst is effective for the addition of glycolate-derived silyl ketene acetals to aldehydes. It was found that the sense of diastereoselectivity could be modulated by changing the size of the substituents on the silyl ketene acetals. In general, the trimethylsilyl ketene acetals derived from methyl glycolates with a large protecting group on the alpha-oxygen provide enantiomerically enriched alpha,beta-dihydroxy esters with high syn-diastereoselectivity, whereas the tert-butyldimethylsilyl ketene acetals derived from bulky esters of alpha-methoxyacetic acid provide enantiomerically enriched alpha,beta-dihydroxy esters with high anti-diastereoselecitvity.

Adsorption of 2,4-dichlorophenoxyacetic acid and 4-chloro-2-metylphenoxyacetic acid onto activated carbons derived from various lignocellulosic materials.

Science.gov (United States)

Doczekalska, Beata; Kuśmierek, Krzysztof; Świątkowski, Andrzej; Bartkowiak, Monika

2018-05-04

Adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-metylphenoxyacetic acid (MCPA) from aqueous solution onto activated carbons derived from various lignocellulosic materials including willow, miscanthus, flax, and hemp shives was investigated. The adsorption kinetic data were analyzed using two kinetic models: the pseudo-first order and pseudo-second order equations. The adsorption kinetics of both herbicides was better represented by the pseudo-second order model. The adsorption isotherms of 2,4-D and MCPA on the activated carbons were analyzed using the Freundlich and Langmuir isotherm models. The equilibrium data followed the Langmuir isotherm. The effect of pH on the adsorption was also studied. The results showed that the activated carbons prepared from the lignocellulosic materials are efficient adsorbents for the removal of 2,4-D and MCPA from aqueous solutions.

In Vivo Anti-inflammatory Activity of Lipoic Acid Derivatives in Mice 

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Brunon Kwiecień

2013-04-01

Full Text Available Background: In mammals lipoic acid (LA and its reduced form dihydrolipoic acid (DHLA function as cofactors for multienzymatic complexes catalyzing the decarboxylation of α-ketoacids. Moreover, LA is used as a drug in a variety of diseases including inflammatory diseases. The aim of the study was to examine anti-inflammatory properties of LA metabolites.Material/methods:The present paper reports the chemical synthesis of 2,4-bismethylthio-butanoic acid (BMTBA and tetranor-dihydrolipoic acid (tetranor-DHLA. BMTBA is one of the biotransformation products of LA, while tetranor-DHLA is an analogue of DHLA. Structural identity of these compounds was confirmed by 1H NMR. These compounds were assessed for their anti-inflammatory activity in mice. For this purpose, the zymosan-induced peritonitis and the carrageenan-induced hind paw edema animal models were applied.Results/conclusions: The obtained results indicated that the early vascular permeability measured at 30 min of zymosan-induced peritonitis was significantly inhibited in groups receiving BMTBA (10, 30, 50 mg/kg. The early infiltration of neutrophils measured at 4 hours of zymosan-induced peritonitis was inhibited in the group receiving BMTBA (50 mg/kg and tetranor-DHLA (50 mg/kg. The results indicated that the increase in paw edema was significantly inhibited in the groups receiving BMTBA (50, 100 mg/kg and tetranor-DHLA (30, 50 mg/kg. In summary, the present studies clearly demonstrated that both BMTBA and tetranor-DHLA were able to act as anti-inflammatory agents. This is the first study examining in vivo the anti-inflammatory properties of LA metabolites.

Identification of oligo-N-glycolylneuraminic acid residues in mammal-derived glycoproteins by a newly developed immunochemical reagent and biochemical methods.

Science.gov (United States)

Sato, C; Kitajima, K; Inoue, S; Inoue, Y

1998-01-30

The occurrence of the alpha2-->8-linked oligomeric form of N-glycolylneuraminic acid (oligo-Neu5Gc) residues in mammalian glycoproteins was unequivocally demonstrated using a newly developed anti-oligo/poly-Neu5Gc monoclonal antibody as well as by chemical and biochemical methods. First, the antibody, designated mAb.2-4B, which specifically recognized oligo/poly-Neu5Gc with a degree of polymerization of >2, was developed by establishing a hybridoma cell line from P3U1 myeloma cells fused with splenocytes from an MRL autoimmune mouse immunized with dipalmitoylphosphatidylethanolamine-conjugated oligo/poly-Neu5Gc. Second, oligo-Neu5Gc was shown to occur in glycoproteins derived from pig spleen by Western blot analysis using mAb.2-4B, which was also confirmed by fluorometric high performance liquid chromatographic analysis of the product of periodate oxidation/reduction/acid hydrolysis of the purified glycopeptide fractions and by TLC and 600-MHz 1H NMR spectroscopic analysis of their mild acid hydrolysates. Finally, the ubiquitous occurrence of oligo-Neu5Gc chains as glycoproteinaceous components in Wistar rat tissue was immunochemically indicated. This is the first example demonstrating the diversity in oligo/poly-Sia structure in mammalian glycoproteins, where only poly-N-acetylneuraminic acid is known to occur. Such diversity in oligo/poly-Sia structure also implicates a diverged array of biological functions of this glycan unit in glycoproteins.

The developmental toxicity of perfluoroalkyl acids and their derivatives

International Nuclear Information System (INIS)

Lau, Christopher; Butenhoff, John L.; Rogers, John M.

2004-01-01

Perfluoroalkyl acids such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) have applications in numerous industrial and consumer products. Although the toxicology of some of these compounds has been investigated in the past, the widespread prevalence of PFOS and PFOA in humans, as demonstrated in recent bio-monitoring studies, has drawn considerable interest from the public and regulatory agencies as well as renewed efforts to better understand the hazards that may be inherent in these compounds. This review provides a brief overview of the perfluoroalkyl chemicals and a summary of the available information on the developmental toxicity of the eight-carbon compounds, PFOS and PFOA. Although the teratological potentials of some of these chemicals had been studied in the past and the findings were generally unremarkable, results from recent postnatal studies on developmental and reproductive indices have prompted consideration of their relevance to human health risk. Based on current understanding of the developmental effects of PFOS and PFOA in rodents, several avenues of research are suggested that would further support the risk assessment of these perfluorinated organic chemicals

Determination and confirmation of nicotinic acid and its analogues and derivates in pear and apple blossoms using high-performance liquid chromatography-diode array-electrospray ionization mass spectrometry.

Science.gov (United States)

Paternoster, Thomas; Vrhovsek, Urska; Pertot, Ilaria; Duffy, Brion; Gessler, Cesare; Mattivi, Fulvio

2009-11-11

Erwinia amylovora causes fire blight, a serious disease of apple and pear. The bacterial pathogen colonizes the flower stigma and hypanthium, where it multiplies and then invades through natural openings (nectarthodes). E. amylovora requires nicotinic acid as growth factor, and competition for nicotinic acid is being explored as a novel biocontrol strategy. The ability of E. amylovora to substitute nicotinic acid with analogues or derivates as growth factors has not been investigated yet. Furthermore, the presence and/or variable concentration of nicotinic acid and its analogues/derivates in the hypanthium could be associated with the different susceptibilities to fire blight of hosts and nonhosts and with the differential sensitivity to the disease among apple and pear varieties. Currently, no methods to specifically quantify nicotinic acid and nicotinic acid analogues/derivates in the hypanthium of apple and pear blossoms are available. This study demonstrates that E. amylovora can grow using nicotinamide and 6-hydroxynicotinic acid as alternative growth factors to nicotinic acid, but not using 2-hydroxynicotinic acid. A novel HPLC/ES-MS method was developed for the detection and quantification of nicotinic acid and its analogues/derivates directly in the hypanthium of apple and pear blossoms. Analyses established the presence of nicotinic acid and nicotinamide, whereas no detectable amounts of 6-hydroxynicotinic acid and 2-hydroxynicotinic acid were observed. Mean nicotinic acid content in the pear hypanthium was found to be approximately 2 orders of magnitude higher than in the apple hypanthium, which may contribute to the differential susceptibility of these two host species to fire blight. Contents of nicotinamide were in contrast similar. Nicotinic acid can therefore be considered a relevant factor in the pathogen establishment in pear blossoms, whereas nicotinamide could cover a primary role in apple blossoms.

Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators of Inflammation to Ameliorate the Deleterious Effects of Blast Overpressure on Eye and Brain Visual Processing Centers in Rats

Science.gov (United States)

2014-10-01

acid ( DHA ; 22:6ω-3) Eicosapentaenoic acid (EPA; 20:5ω-3) Lipoxin A4 Resolvin E1 Protectin DX Resolvin D1 LOX LOX LOX Structures and Endogenous Source...1 AD_________________ Award Number: W81XWH-12-2-0082 TITLE: Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid...Evaluation of Novel Polyunsaturated Fatty Acid Derived Lipid Mediators 5a. CONTRACT NUMBER of Inflammation to Ameliorate the Deleterious Effects of

OxymaPure/DIC: An Efficient Reagent for the Synthesis of a Novel Series of 4-[2-(2-Acetylaminophenyl-2-oxo-acetylamino] Benzoyl Amino Acid Ester Derivatives

Directory of Open Access Journals (Sweden)

Ayman El-Faham

2013-11-01

Full Text Available OxymaPure (ethyl 2-cyano-2-(hydroxyiminoacetate was tested as an additive for use in the carbodiimide (DIC approach for the synthesis of a novel series of α-ketoamide derivatives (4-[2-(2-acetylaminophenyl-2-oxo-acetylamino]benzoyl amino acid ester derivatives. OxymaPure showed clear superiority to HOBt/DIC or carbodiimide alone in terms of purity and yield. The title compounds were synthesized via the ring opening of N-acylisatin. First, N-acetylisatin was reacted with 4-aminobenzoic acid under conventional heating as well as microwave irradiation to afford 4-(2-(2-acetamidophenyl-2-oxoacetamidobenzoic acid. This α-ketoamide was coupled to different amino acid esters using OxymaPure/DIC as a coupling reagent to afford 4-[2-(2-acetylaminophenyl-2-oxo-acetylamino]benzoyl amino acid ester derivatives in excellent yield and purity. The synthesized compounds were characterized using FT-IR, NMR, and elemental analysis.

Mono- and bis(pyrrolo)tetrathiafulvalene derivatives tethered to C60

DEFF Research Database (Denmark)

Vico Solano, Marta; Della Pia, Eduardo Antonio; Jevric, Martyn

2014-01-01

-functionalized MPTTF/BPTTF derivatives, two different tailor-made amino acids, and C-60. Electronic communication between the MPTTF/BPTTF units and the C-60 moieties was studied by a variety of techniques including cyclic voltammetry and absorption spectroscopy. These solution-based studies indicated no observable...

Electrochemical measurements for the corrosion inhibition of mild steel in 1 M hydrochloric acid by using an aromatic hydrazide derivative

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P. Preethi Kumari

2017-07-01

Full Text Available The influence of an aromatic hydrazide derivative, 2-(3,4,5-trimethoxybenzylidene hydrazinecarbothioamide (TMBHC as corrosion inhibitor on mild steel in 1 M hydrochloric acid was studied by Tafel polarization and electrochemical impedance spectroscopy (EIS technique. The results showed that the inhibition efficiency (% IE of TMBHC increased with increasing inhibitor concentrations and also with increase in temperatures. TMBHC acted as a mixed type of inhibitor and its adsorption on mild steel surface was found to follow Langmuir’s adsorption isotherm. The evaluation of thermodynamic and activation parameters indicated that the adsorption of TMBHC takes place through chemisorption. The formation of protective film was further confirmed by scanning electron microscopy (SEM.

Application of bone marrow and adipose-derived mesenchymal stem cells for testing the biocompatibility of metal-based biomaterials functionalized with ascorbic acid

International Nuclear Information System (INIS)

Marycz, Krzysztof; Śmieszek, Agnieszka; Grzesiak, Jakub; Donesz-Sikorska, Anna; Krzak-Roś, Justyna

2013-01-01

In this study, metal-based biomaterials were functionalized with ascorbic acid (LAA). Two types of substrates were used: austenitic steel 316L and titanium Ti6Al4V. Coatings were prepared with the sol–gel method and applied on metal surfaces using the dip-coating technique. Ascorbic acid was delivered with SiO 2 -coating at concentrations of 0.1 and 0.4 M. The morphology of the surfaces and coatings was determined using scanning electron microscope (SEM), whereas their elemental composition by SEM-EDX. Immobilization of ascorbic acid in the coatings was confirmed with Raman spectroscopy. The biocompatibility of the materials obtained was tested in vitro using both bone marrow- and adipose-derived mesenchymal stem cells (BMMSC and ADMSC, respectively). Proliferation rate and morphology of cells cultured in the presence of designed biomaterials were monitored after 24, 48, 120 and 168 h of propagation. The results obtained indicated that silica coatings doped with 0.4 M LAA had a positive effect on the proliferation rate of investigated cells, and in some cases on the growth pattern of culture. (paper)

Effects of secondary alteration on the composition of free and IOM-derived monocarboxylic acids in carbonaceous chondrites

Science.gov (United States)

Aponte, José C.; Alexandre, Marcelo R.; Wang, Yi; Brearley, Adrian J.; Alexander, Conel M. O.'D.; Huang, Yongsong

2011-05-01

Monocarboxylic acids (MCAs) are important astrobiologically because they are often the most abundant soluble compounds in carbonaceous chondrites (CCs) and are potential synthetic end products for many biologically important compounds. However, there has been no systematic study on the effect of parent body alteration on molecular and isotopic variability of MCAs. Since MCAs in meteorites are dominated by low molecular weight (C1-C8), highly volatile compounds, their distributions are likely to be particularly sensitive to secondary alteration processes. In contrast, the aliphatic side chains of insoluble organic matter (IOM) in CCs, whose composition has been shown to be closely related to the MCAs, may be far more resistant to secondary alteration. In the present study, we determined the distributions and isotopic ratios of free and IOM-derived MCAs in six carbonaceous chondrites with a range of classifications: Murchison (CM2), EET 87770 (CR2), ALH 83034 (CM1), ALH 83033 (CM2), MET 00430 (CV3) and WIS 91600 (C2). We compare mineralogical and petrological characteristics to the MCAs distributions to better define the processes leading to the synthesis and alteration of meteoritic MCAs. Our results show that aqueous and especially thermal alteration in the parent bodies led to major loss of free MCAs and depletion of straight relative to branched chain compounds. However, the MCAs derived from aliphatic side chains of IOM are well preserved despite of secondary alterations. The molecular and isotopic similarities of IOM-derived MCAs in different chondrite samples indicate very similar synthetic histories for organic matter in different meteorites.

Immune Modulation in Normal Human Peripheral Blood Mononuclear Cells (PBMCs) (Lymphocytes) in Response to Benzofuran-2-Carboxylic Acid Derivative KMEG during Spaceflight

Science.gov (United States)

Okoro, Elvis; Mann, Vivek; Ellis, Ivory; Mansoor, Elvedina; Olamigoke, Loretta; Marriott, Karla Sue; Denkins, Pamela; Williams, Willie; Sundaresan, Alamelu

2017-08-01

Microgravity and radiation exposure during space flight have been widely reported to induce the suppression of normal immune system function, and increase the risk of cancer development in humans. These findings pose a serious risk to manned space missions. Interestingly, recent studies have shown that benzofuran-2-carboxylic acid derivatives can inhibit the progression of some of these devastating effects on earth and in modeled microgravity. However, these studies had not assessed the impacts of benzofuran-2- carboxylic acid and its derivatives on global gene expression under spaceflight conditions. In this study, the ability of a specific benzofuran-2-carboxylic acid derivative (KMEG) to confer protection from radiation and restore normal immune function was investigated following exposure to space flight conditions on the ISS. Normal human peripheral blood mononuclear cells (lymphocytes) treated with 10 µ g/ml of KMEG together with untreated control samples were flown on Nanoracks hardware on Spacex-3 flight. The Samples were returned one month later and gene expression was analyzed. A 1g-ground control experiment was performed in parallel at the Kennedy spaceflight center. The first overall subtractive unrestricted analysis revealed 78 genes, which were differentially expressed in space flight KMEG, untreated lymphocytes as compared to the corresponding ground controls. However, in KMEG-treated space flight lymphocytes, there was an increased expression of a group of genes that mediate increased transcription, translation and innate immune system mediating functions of lymphocytes as compared to KMEG-untreated samples. Analysis of genes related to T cell proliferation in spaceflight KMEG-treated lymphocytes compared to 1g-ground KMEG- treated lymphocytes revealed six T cell proliferation and signaling genes to be significantly upregulated (p trafficking, promote early response, mediating C-myc related proliferation, promote antiapoptotic activity and protects

3D-QSAR Studies on Barbituric Acid Derivatives as Urease Inhibitors and the Effect of Charges on the Quality of a Model.

Science.gov (United States)

Ul-Haq, Zaheer; Ashraf, Sajda; Al-Majid, Abdullah Mohammed; Barakat, Assem

2016-04-30

Urease enzyme (EC 3.5.1.5) has been determined as a virulence factor in pathogenic microorganisms that are accountable for the development of different diseases in humans and animals. In continuance of our earlier study on the helicobacter pylori urease inhibition by barbituric acid derivatives, 3D-QSAR (three dimensional quantitative structural activity relationship) advance studies were performed by Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices Analysis (CoMSIA) methods. Different partial charges were calculated to examine their consequences on the predictive ability of the developed models. The finest developed model for CoMFA and CoMSIA were achieved by using MMFF94 charges. The developed CoMFA model gives significant results with cross-validation (q²) value of 0.597 and correlation coefficients (r²) of 0.897. Moreover, five different fields i.e., steric, electrostatic, and hydrophobic, H-bond acceptor and H-bond donors were used to produce a CoMSIA model, with q² and r² of 0.602 and 0.98, respectively. The generated models were further validated by using an external test set. Both models display good predictive power with r²pred ≥ 0.8. The analysis of obtained CoMFA and CoMSIA contour maps provided detailed insight for the promising modification of the barbituric acid derivatives with an enhanced biological activity.

3D-QSAR Studies on Barbituric Acid Derivatives as Urease Inhibitors and the Effect of Charges on the Quality of a Model

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Zaheer Ul-Haq

2016-04-01

Full Text Available Urease enzyme (EC 3.5.1.5 has been determined as a virulence factor in pathogenic microorganisms that are accountable for the development of different diseases in humans and animals. In continuance of our earlier study on the helicobacter pylori urease inhibition by barbituric acid derivatives, 3D-QSAR (three dimensional quantitative structural activity relationship advance studies were performed by Comparative Molecular Field Analysis (CoMFA and Comparative Molecular Similarity Indices Analysis (CoMSIA methods. Different partial charges were calculated to examine their consequences on the predictive ability of the developed models. The finest developed model for CoMFA and CoMSIA were achieved by using MMFF94 charges. The developed CoMFA model gives significant results with cross-validation (q2 value of 0.597 and correlation coefficients (r2 of 0.897. Moreover, five different fields i.e., steric, electrostatic, and hydrophobic, H-bond acceptor and H-bond donors were used to produce a CoMSIA model, with q2 and r2 of 0.602 and 0.98, respectively. The generated models were further validated by using an external test set. Both models display good predictive power with r2pred ≥ 0.8. The analysis of obtained CoMFA and CoMSIA contour maps provided detailed insight for the promising modification of the barbituric acid derivatives with an enhanced biological activity.

An automated system for access to derived climate indices in support of ecological impacts assessments and resource management

Science.gov (United States)

Walker, J.; Morisette, J. T.; Talbert, C.; Blodgett, D. L.; Kunicki, T.

2012-12-01

A U.S. Geological Survey team is working with several providers to establish standard data services for the climate projection data they host. To meet the needs of climate adaptation science and landscape management communities, the team is establishing a set of climate index calculation algorithms that will consume data from various providers and provide directly useful data derivatives. Climate projections coming from various scenarios, modeling centers, and downscaling methods are increasing in number and size. Global change impact modeling and assessment, generally, requires inputs in the form of climate indices or values derived from raw climate projections. This requirement puts a large burden on a community not familiar with climate data formats, semantics, and processing techniques and requires storage capacity and computing resources out of the reach of most. In order to fully understand the implications of our best available climate projections, assessments must take into account an ensemble of climate projections and potentially a range of parameters for calculation of climate indices. These requirements around data access and processing are not unique from project to project, or even among projected climate data sets, pointing to the need for a reusable tool to generate climate indices. The U.S. Geological Survey has developed a pilot application and supporting web service framework that automates the generation of climate indices. The web service framework consists of standards-based data servers and a data integration broker. The resulting system allows data producers to publish and maintain ownership of their data and data consumers to access climate derivatives via a simple to use "data product ordering" workflow. Data access and processing is completed on enterprise "cloud" computing resources and only the relatively small, derived climate indices are delivered to the scientist or land manager. These services will assist the scientific and land

Antineurodegenerative effect of phenolic extracts and caffeic acid derivatives in romaine lettuce on neuron-like PC-12 cells.

Science.gov (United States)

Im, Sung-Eun; Yoon, Hyungeun; Nam, Tae-Gyu; Heo, Ho Jin; Lee, Chang Yong; Kim, Dae-Ok

2010-08-01

In recent decades, romaine lettuce has been one of the fastest growing vegetables with respect to its consumption and production. An understanding is needed of the effect of major phenolic phytochemicals from romaine lettuce on biological protection for neuron-like PC-12 cells. Phenolics in fresh romaine lettuce were extracted, and then its total phenolics and total antioxidant capacity were measured spectrophotometrically. Neuroprotective effects of phenolic extract of romaine lettuce and its pure caffeic acid derivatives (caffeic, chicoric, chlorogenic, and isochlorogenic acids) in PC-12 cells were evaluated using two different in vitro methods: lactate dehydrogenase release and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction assays. Total phenolics and total antioxidant capacity of 100 g of fresh romaine lettuce averaged 22.7 mg of gallic acid equivalents and 31.0 mg of vitamin C equivalents, respectively. The phenolic extract of romaine lettuce protected PC-12 cells against oxidative stress caused by H(2)O(2) in a dose-dependent manner. Isochlorogenic acid, one of the phenolics in romaine lettuce, showed stronger neuroprotection than the other three caffeic acid derivatives also found in the lettuce. Although romaine lettuce had lower levels of phenolics and antioxidant capacity compared to other common vegetables, its contribution to total antioxidant capacity and antineurodegenerative effect in human diets would be higher because of higher amounts of its daily per capita consumption compared to other common vegetables.

Characterization and antioxidant activity of gallic acid derivative

Science.gov (United States)

Malinda, Krissan; Sutanto, Hery; Darmawan, Akhmad

2017-11-01

Peroxidase enzyme was used to catalyze the dimerization process of gallic acid. The structure of the dimerization product was characterized by 1H NMR and LC-MS-MS. The mechanism of gallic acid dimerization was also discussed. It was proposed that ellagic acid was formed through an oxidative coupling mechanism that lead to the formation of a C-C bond and followed by an intramolecular Fischer esterification mechanism that lead to the formation of two C-O bonds. Moreover, the antioxidant activity of gallic acid and ellagic acid were also studied. Gallic acid and ellagic acid exhibited the DPPH radical scavenging activity with IC50 values of 13.2 μM and 15.9 μM, respectively.

Design and Synthesis of Bis-amide and Hydrazide-containing Derivatives of Malonic Acid as Potential HIV-1 Integrase Inhibitors

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Nouri Neamati

2008-10-01

Full Text Available HIV-1 integrase (IN is an attractive and validated target for the development of novel therapeutics against AIDS. In the search for new IN inhibitors, we designed and synthesized three series of bis-amide and hydrazide-containing derivatives of malonic acid. We performed a docking study to investigate the potential interactions of the title compounds with essential amino acids on the IN active site.

Periconceptional bread intakes indicate New Zealand's proposed mandatory folic acid fortification program may be outdated: results from a postpartum survey.

Science.gov (United States)

Mallard, Simonette R; Gray, Andrew R; Houghton, Lisa A

2012-02-14

In September 2009, a folic acid fortification mandate (135 μg/100 g bread) was to be implemented in New Zealand. However, due to political and manufacturer objection, fortification was deferred until May 2012. Based on estimates of bread consumption derived from a 1997 nationally representative survey, this program was intended to deliver a mean additional intake of 140 μg folic acid/d to women of childbearing age. Little is known about current bread consumption patterns in this target group. The aim of this study was to assess bread consumption among women prior to and during pregnancy with the intent to estimate periconceptional folic acid intakes that would be derived from bread if mandatory fortification were implemented as currently proposed. A retrospective survey of 723 postpartum women in hospitals and birthing centres across New Zealand was conducted using a self-administered questionnaire on bread intake prior to and during pregnancy and maternal socio-demographic and obstetric characteristics. Median bread intake before conception (2 slices/d) was below that of previous data upon which the current fortification proposal was modeled (3-4 slices/d). If mandatory fortification is implemented as proposed, only 31% (95% CI = 24%-37%) of childbearing-age women would attain an additional folic acid intake of ≥ 140 μg/d, with a mean of 119 μg/d (95% CI = 107 μg/d-130 μg/d). Based on these data, a fortification level of 160 μg/100 g bread is required to achieve the targeted mean of 140 μg folic acid/d. Nonetheless, under the current proposal additional folic acid intakes would be greatest among the least advantaged segments of the target population: Pacific and indigenous Māori ethnic groups; those with increased parity, lower income and education; younger and single mothers; and women with unplanned pregnancies. Subgroups predicted to derive less than adequate folic acid intakes from the proposed policy were women of Asian descent and those with a

Periconceptional bread intakes indicate New Zealand's proposed mandatory folic acid fortification program may be outdated: results from a postpartum survey

Science.gov (United States)

2012-01-01

Background In September 2009, a folic acid fortification mandate (135 μg/100 g bread) was to be implemented in New Zealand. However, due to political and manufacturer objection, fortification was deferred until May 2012. Based on estimates of bread consumption derived from a 1997 nationally representative survey, this program was intended to deliver a mean additional intake of 140 μg folic acid/d to women of childbearing age. Little is known about current bread consumption patterns in this target group. The aim of this study was to assess bread consumption among women prior to and during pregnancy with the intent to estimate periconceptional folic acid intakes that would be derived from bread if mandatory fortification were implemented as currently proposed. Methods A retrospective survey of 723 postpartum women in hospitals and birthing centres across New Zealand was conducted using a self-administered questionnaire on bread intake prior to and during pregnancy and maternal socio-demographic and obstetric characteristics. Results Median bread intake before conception (2 slices/d) was below that of previous data upon which the current fortification proposal was modeled (3-4 slices/d). If mandatory fortification is implemented as proposed, only 31% (95% CI = 24%-37%) of childbearing-age women would attain an additional folic acid intake of ≥ 140 μg/d, with a mean of 119 μg/d (95% CI = 107 μg/d-130 μg/d). Based on these data, a fortification level of 160 μg/100 g bread is required to achieve the targeted mean of 140 μg folic acid/d. Nonetheless, under the current proposal additional folic acid intakes would be greatest among the least advantaged segments of the target population: Pacific and indigenous Māori ethnic groups; those with increased parity, lower income and education; younger and single mothers; and women with unplanned pregnancies. Subgroups predicted to derive less than adequate folic acid intakes from the proposed policy were women of Asian

Analysis of Post-Fire Vegetation Recovery in the Mediterranean Basin using MODIS Derived Vegetation Indices

Science.gov (United States)

Hawtree, Daniel; San Miguel, Jesus; Sedano, Fernando; Kempeneers, Pieter

2010-05-01

The Mediterranean basin region is highly susceptible to wildfire, with approximately 60,000 individual fires and half a million ha of natural vegetation burnt per year. Of particular concern in this region is the impact of repeated wildfires on the ability of natural lands to return to a pre-fire state, and of the possibility of desertification of semi-arid areas. Given these concerns, understanding the temporal patterns of vegetation recovery is important for the management of environmental resources in the region. A valuable tool for evaluating these recovery patterns are vegetation indices derived from remote sensing data. Previous research on post-fire vegetation recovery conducted in this region has found significant variability in recovery times across different study sites. It is unclear what the primary variables are affecting the differences in the rates of recovery, and if any geographic patterns of behavior exist across the Mediterranean basin. This research has primarily been conducted using indices derived from Landsat imagery. However, no extensive analysis of vegetation regeneration for large regions has been published, and assessment of vegetation recovery on the basis of medium-spatial resolution imagery such as that of MODIS has not yet been analyzed. This study examines the temporal pattern of vegetation recovery in a number of fire sites in the Mediterranean basin, using data derived from MODIS 16 -day composite vegetation indices. The intent is to develop a more complete picture of the temporal sequence of vegetation recovery, and to evaluate what additional factors impact variations in the recovery sequence. In addition, this study evaluates the utility of using MODIS derived vegetation indices for regeneration studies, and compares the findings to earlier studies which rely on Landsat data. Wildfires occurring between the years 2000 and 2004 were considered as potential study sites for this research. Using the EFFIS dataset, all wildfires

Library of Antifouling Surfaces Derived From Natural Amino Acids by Click Reaction.

Science.gov (United States)

Xu, Chen; Hu, Xin; Wang, Jie; Zhang, Ye-Min; Liu, Xiao-Jiu; Xie, Bin-Bin; Yao, Chen; Li, Yi; Li, Xin-Song

2015-08-12

Biofouling is of great concern in numerous applications ranging from ophthalmological implants to catheters, and from bioseparation to biosensors. In this report, a general and facile strategy to combat surface fouling is developed by grafting of amino acids onto polymer substrates to form zwitterionic structure through amino groups induced epoxy ring opening click reaction. First of all, a library of poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) hydrogels with zwitterionic surfaces were prepared, resulting in the formation of pairs of carboxyl anions and protonated secondary amino cations. The analysis of attenuated total reflectance Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirmed the successful immobilization of amino acids on the hydrogel surfaces. After that, the contact angle and equilibrium water content of the modified hydrogels showed that the hydrogels exhibited improved hydrophilicity compared with the parent hydrogel. Furthermore, the protein deposition was evaluated by bicinchoninic acid assay using bovine serum albumin (BSA) and lysozyme as models. The results indicated that the performance of the hydrogels was determined by the nature of incorporated amino acid: the hydrogels incorporated with neutral amino acids had nonspecific antiadsorption capability to both BSA and lysozyme; the hydrogels incorporated with charged amino acids showed antiadsorption behaviors against protein with same charge and enhanced adsorption to the protein with opposite charge; the optimal antiadsorption performance was observed on the hydrogels incorporated with polar amino acids with a hydroxyl residual. The improvement of antiprotein fouling of the neutral amino acids grafted hydrogels can be ascribed to the formation of zwitterionic surfaces. Finally, a couple of soft contact lenses grafted with amino acids were fabricated having improved antifouling property and hydrophilicity. The result demonstrated the success of

Root-uptake of {sup 14}C derived from acetic acid and {sup 14}C transfer to rice edible parts

Energy Technology Data Exchange (ETDEWEB)

Ogiyama, Shinichi [Office of Biospheric Assessment for Waste Disposal, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555 (Japan)], E-mail: ogiyama@nirs.go.jp; Suzuki, Hiroyuki [Graduate School of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-5522 (Japan); Inubushi, Kazuyuki [Graduate School of Horticulture, Chiba University, 648 Matsudo, Matsudo-shi 271-8510 (Japan); Takeda, Hiroshi; Uchida, Shigeo [Office of Biospheric Assessment for Waste Disposal, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-shi 263-8555 (Japan)

2010-02-15

Three types of culture experiments using paddy rice (Oryza sativa L.) were performed to examine root-uptake of {sup 14}C in the form of acetic acid: double pot experiment (hydroponics), wet culture experiment (submerged sand medium), and chamber experiment (hydroponics and submerged sand medium). The {sup 14}C radioactivity in the plant, mediums, and atmospheric carbon dioxide ({sup 14}CO{sub 2}) in the chamber were determined, and the distribution of {sup 14}C in the plant was visualized using autoradiography. In the double pot experiment, the shoot of the plant and the lower root which was soaked in the culture solution had {sup 14}C radioactivity, but the upper root which did not have contact with the solution had none. There were also {sup 14}C radioactivity in the grains and roots in the wet culture experiment. Results of the chamber experiment showed that {sup 14}CO{sub 2} gas was released from the culture solution in both types of cultures. Results indicated that the {sup 14}C-acetic acid absorbed by rice plant through its root would be very small. Most of the {sup 14}C-acetic acid was transformed into gaseous forms either in the culture solution or rhizosphere. A relatively longer time would be needed to assimilate {sup 14}C derived from acetic acid to grain parts after it was once absorbed by the shoot through the root. Availability of {sup 14}C for the plant in sand culture was considered to be decreased compared with that for the plant in the hydroponics experiment. It was suggested that rice plant absorbed and assimilated {sup 14}C through the plant roots not because of uptake of {sup 14}C-acetic acid but because of uptake of {sup 14}C in gaseous forms such as {sup 14}CO{sub 2}.

Determining aromatic and aliphatic carboxylic acids in biomass-derived oil samples using 2,4-dinitrophenylhydrazine and liquid chromatography-electrospray injection-mass spectrometry/mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Lewis, Samuel A.; Connatser, Raynella M.; Olarte, Mariefel V.; Keiser, James R.

2018-01-01

Converting biomass to a useful fuel commonly incorporates the pyrolysis of the biomass feed stock. The base liquid fraction usually contains high concentrations of ketones, aldehydes and carboxylic acids, of which each can cause detrimental issues related to the storage and upgrading process. Knowing the carbonyl species and the concentration of each will provide value information to the pyrolysis researchers, specifically as that community branches into more targeted end-products such as jet fuel or biogenic-derived oxygenate-containing fuel products. The analysis of aldehydes, ketones and small alkyl carboxylic acids using 2,4-dinitrophenylhydrazine (DNPH) derivation method has been well documented and the method is commonly used the analytical community. By using liquid chromatograph coupled to tandem mass spectrometry, biomass sample analysis can be complete with identification of most carbonyl species. The issue of identifying isobaric ketone and aldehyde compounds can be resolved by utilizing differences in retention time or characteristic fragment ions of ketones and aldehydes. One issue which could not resolved using published methods was identifying aromatic or large non-aromatic carboxylic acids from their corresponding hydroxyl aldehyde or ketone analogs. By modifying the current method for determining carbonyls in biomass samples, carboxylic and hydroxyl-carbonyl can be determined. A careful adjustment of the pH during the extraction procedure and extended heating time of the DNPH solution allowed for the successful derivation of aromatic carboxylic acids. Like other dinitrophenylhydrazones, carboxylic acid derivatives also produce a unique secondary ion pattern, which was useful to distinguish these species from the non-acid analogs.

Kinetics of Oxidation of Some Amino Acids by N-Chlorosaccharin in Aqueous Acetic Acid Medium

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N. A. Mohamed Farook

2004-01-01

Full Text Available The kinetics of oxidation of some amino acids namely, glycine, alanine, aspartic acid, arginine, and histidine, (AA by N-chlorosaccharin (NCSA in aqueous acetic acid medium in the presence of perchloric acid have been investigated. The observed rate of oxidation is first order in [AA], [NCSA] and of inverse fractional order in [H+]. The main product of the oxidation is the corresponding aldehyde. The ionic strength on the reaction rate has no significant effect. The effect of changing the dielectric constant of the medium on the rate indicates the reaction to be of dipole-dipole type. Hypochlorous acid has been postulated as the reactive oxidizing species. The reaction constants involved in the mechanism are derived. The activation parameters are computed with respect to slow step of the mechanism.

Chirality of meteoritic free and IOM-derived monocarboxylic acids and implications for prebiotic organic synthesis

Science.gov (United States)

Aponte, José C.; Tarozo, Rafael; Alexandre, Marcelo R.; Alexander, Conel M. O.'D.; Charnley, Steven B.; Hallmann, Christian; Summons, Roger E.; Huang, Yongsong

2014-04-01

The origin of homochirality and its role in the development of life on Earth are among the most intriguing questions in science. It has been suggested that carbonaceous chondrites seeded primitive Earth with the initial organic compounds necessary for the origin of life. One of the strongest pieces of evidence supporting this theory is that certain amino acids in carbonaceous chondrites display a significant L-enantiomeric excess (ee), similar to those use by terrestrial life. Analyses of ee in meteoritic molecules other than amino acids would shed more light on the origins of homochirality. In this study we investigated the stereochemistry of two groups of compounds: (1) free monocarboxylic acids (MCAs) from CM2 meteorites LON 94101 and Murchison; and (2) the aliphatic side chains present in the insoluble organic matter (IOM) and extracted in the form of monocarboxylic acids (MCAs) from EET 87770 (CR2) and Orgueil (CI1). Contrary to the well-known ee observed for amino acids in meteorites, we found that meteoritic branched free and IOM-derived MCAs with 5-8 carbon atoms are essentially racemic. The racemic nature of these compounds is used to discuss the possible influence of ultraviolet circularly polarized light (UVCPL) and aqueous alterations on the parent body on chirality observed in in carbonaceous chondrites.

Hypolipidemic and hypoglycemic activities of a oleanolic acid derivative from Malva parviflora on streptozotocin-induced diabetic mice.

Science.gov (United States)

Gutiérrez, Rosa Martha Pérez

2017-05-01

One new oleanolic acid derivative, 2α,3β,23α,29α tetrahydroxyolean-12(13)-en-28-oic acid (1) was isolated from the aerial parts of Malva parviflora. Their structure was characterized by spectroscopic methods. The hypolipidemic and hypoglycemic activities of 1 was analyzed in in streptozotocin (STZ)-nicotinamide-induced type 2 diabetes in mice (MD) and type 1 diabetes in streptozotocin-induced diabetic mice (SD). Triterpene was administered orally at doses of 20 mg/kg for 4 weeks. Organ weight, body weight, glucose, fasting insulin, cholesterol-related lipid profile parameters, glutamate oxaloacetate transaminase (SGOT), glutamate pyruvate transaminase (SGPT), serum alkaline phosphatase (SALP), glucokinase, hexokinase, glucose-6-phosphatase activities and glycogen in liver were measured after 4 weeks of treatment. The results indicated that 1 regulate glucose metabolism, lipid profile, lipid peroxidation, increased body weight, glucokinase and hexokinase activities inhibited triglycerides, total cholesterol, low density lipoproteins level, SGOT, SGPT, SALP, glycogen in liver and glucose-6-phosphatase. In addition, improvement of insulin resistance and protective effect for pancreatic β-cells, also 1 may changes the expression of pro-inflammatory cytokine (IL-6 and TNF-α levels) and enzymes (PAL2, COX-2, and LOX). The results suggest that 1 has hypolipidemic and hypoglycemic, anti-inflammatory, activities, improve insulin resistance and hepatic enzymes in streptozotocin-induced diabetic mice.

Synthesis of new oxovanadium (IV) complexes of potential insulinmimetic activity with coumarin-3-carboxylic acid ligands and substituted derivatives

International Nuclear Information System (INIS)

Salas Fernandez, Paloma; Alvino de la Sota, Nora; Galli Rigo-Righi, Carla

2013-01-01

This work comprises the design and synthesis of four new oxovanadium (IV) complexes, a metal which possesses insulin-mimetic action. Coumarin-3-carboxylic acid and three of its 6 -and 6,8- derivatives were used as ligands. Coumarins are of interest due to their well-known biological properties and pharmacological applications; these include the insulino-sensibilizing effect of certain alcoxy-hydroxy-derivatives which might lead to the eventual existence of a synergetic effect with the active metal center. The synthesis of the vanadyl complexes was preceded by the synthesis of the coumarin-3-carboxylic acid and its 6-bromo- derivative, as well as the syntheses of three derivatives not previously reported: 6-bromo-8-metoxi-, 6-bromo-8-nitro-, and 6-bromo-8-hydroxy-, which were prepared by a Knoevenagel condensation reaction. The complexes, on their part, were prepared by a metathesis reaction between VOSO 4 and the corresponding ligands, on the basis of methods reported for other vanadyl complexes and under strict pH control. The coumarin-3-carboxylic ligands and the derivatives were characterized by 1 H-NMR-, FTIR- and UV-Vis-spectroscopy. In the case of the complexes, their paramagnetic character did not allow for NMR characterization, being thus identified by FT-IR-spectroscopy and by the quantitative determination of their vanadium contents. (author)

Nucleic acid stains as indicators of Giardia muris viability following cyst inactivation.

Science.gov (United States)

Taghi-Kilani, R; Gyürék, L L; Millard, P J; Finch, G R; Belosevic, M

1996-06-01

A reliable viability assay for Giardia is required for the development of disinfection process design criteria and pathogen monitoring by water treatment utilities. Surveys of single-staining nucleic acid dyes (stain dead parasites only), and double-staining vital dye kits from Molecular Probes (stain live and dead parasites) were conducted to assess the viability of untreated, heat-killed, and chemically inactivated Giardia muris cysts. Nucleic acid staining results were compared to those of in vitro excystation and animal infectivity. Nucleic acid stain, designated as SYTO-9, was considered the best among the single-staining dyes for its ability to stain dead cysts brightly and its relatively slow decay rate of visible light emission following DNA binding. SYTO-9 staining was correlated to animal infectivity. A Live/Dead BacLight was found to be the better of 2 double-staining viability kits tested. Logarithmic survival ratios based on SYTO-9 and Live/Dead BacLight were compared to excystation and infectivity results for G. muris cysts exposed to ozone or free chlorine. The results indicate that SYTO-9 and Live/Dead BacLight staining is stable following treatment of cysts with chemical disinfectants.

An evaluation of the physiological activity of 9-amine-9-fluorenephosphonic acid derivatives

Directory of Open Access Journals (Sweden)

Henryk Skrabka

2013-12-01

Full Text Available The physiological activity of eleven 9-amine-9-fluorenephosphonic acid derivatives, synthesized at the Wrocław Polytechnic, was examined. The test plant was Spirodela oligorrhiza. The effect of these compounds on the increase of the dry matter of this plant was tested in eight-day experiments. The activity of the compounds was varied. The most toxic were nos. 2, 4, 9, 8, 5 and 6 which were lethal in low concentrations. Somewhat less toxic were nos. 7, 10 and 11; nos. 1 and 3 were the least toxic.

The marine sponge-derived polyketide endoperoxide plakortide F acid mediates its antifungal activity by interfering with calcium homeostasis

Science.gov (United States)

Plakortide F acid (PFA) is a marine-derived polyketide endoperoxide exhibiting strong inhibitory activity against several clinically important fungal pathogens. In the present study, transcriptional profiling coupled with mutant and biochemical analyses were conducted using the model organism Sacch...

α-Amino Acid Derived Benzimidazole-Linked Rhodamines: A Case of Substitution Effect at the Amino Acid Site toward Spiro Ring Opening for Selective Sensing of Al3+ Ions.

Science.gov (United States)

Majumdar, Anupam; Mondal, Subhendu; Daniliuc, Constantin G; Sahu, Debashis; Ganguly, Bishwajit; Ghosh, Sourav; Ghosh, Utpal; Ghosh, Kumaresh

2017-08-07

α-Amino acid derived benzimidazole-linked rhodamines have been synthesized, and their metal ion sensing properties have been evaluated. Experimentally, l-valine- and l-phenylglycine-derived benzimidazole-based rhodamines 1 and 2 selectively recognize Al 3+ ion in aqueous CH 3 CN (CH 3 CN/H 2 O 4/1 v/v, 10 mM tris HCl buffer, pH 7.0) over the other cations by exhibiting color and "turn-on" emission changes. In contrast, glycine-derived benzimidazole 3 remains silent in the recognition event and emphasizes the role of α-substitution of amino acid undertaken in the design. The fact has been addressed on the basis of the single-crystal X-ray structures and theoretical calculations. Moreover, pink 1·Al 3+ and 2·Al 3+ ensembles selectively sensed F - ions over other halides through a discharge of color. Importantly, compounds 1 and 2 are cell permeable and have been used as imaging reagents for the detection of Al 3+ uptake in human lung carcinoma cell line A549.

Disinfection efficiency of peracetic acid (PAA): inactivation of coliphages and bacterial indicators in a municipal wastewater plant.

Science.gov (United States)

Zanetti, F; De Luca, G; Sacchetti, R; Stampi, S

2007-11-01

The aim of the study was to assess the efficiency of low doses of peracetic acid against viral and bacterial indicators in wastewater and to evaluate if the treatment allows regulatory requirements to be satisfied. A total of 31 samplings were carried out, each involving the collection of secondary effluent and of effluent disinfected with 1.2 or 1.5 mg l(-1) of peracetic acid (contact time 20 minutes). In each sample were measured: somatic coliphages, F-specific RNA bacteriophages, Escherichia coli, total and faecal coliforms, enterococci. Peracetic acid disinfection showed significant differences between the reductions of the microorganisms tested: E. coli showed the highest reduction (1.78 and 2.43 Log respectively with 1.2 and 1.5 mg l(-1) of peracetic acid) and phages the lowest (ranging between 0.52 and 0.60 Log). Only a concentration of 1.5 mg l(-1) of peracetic acid would enable the effluent to be discharged into surface waters in compliance with Italian regulations. The variability of microbial resistance against the peracetic acid disinfection treatment, underlines the importance of assessing disinfection efficiency by using more than one indicator microorganism. The detection of E. coli could be usefully accompanied by tests for more resistant microorganisms such as enterococci or coliphages. In conclusion, peracetic acid can be used for the disinfection of effluents even at low doses, with the advantage of reducing costs and preventing the formation of significant amounts of genotoxic by-products.

On complex compounds of molybdenum(5) with nicotinic amide, isonicotinic acid hydrazide and some of its derivatives

International Nuclear Information System (INIS)

Azizov, M.M.; Kushakbaev, A.; Parpiev, N.A.

1977-01-01

Oxychloride complexes of molybdenum (5) with polyfunctional ligands (L), namely with nicotinamide (NA), isonicotinic acid hydrazide (INH) and its derivatives (ftivazide, saluzide and larusan) have been synthesized and investigated. In ethanol all the ligands independently of their molar ratio form with MoCl 5 a non-electrolite compound MoOCl 3 xL 2 . Infrared spectra of the complexes suggest that in Mo(5) complexeS with NA and INH the central atom is bound through the pyridine nitrogen, whereas in the complexes with INH derivatives it is bound throught the carbonyl group oxygen

Effect of Temperature on the Kinetics of Sorption of Co2+ and Ni2+ Ions by a Sorbent Based on an Inositol Hexaphosphoric Acid Derivative

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Yarusova, S. B.; Makarenko, N. V.; Gordienko, P. S.; Karpenko, M. A.; Novikova, E. S.

2018-03-01

Data on the effect temperature has on the kinetics of the removal of Co2+ and Ni2+ ions under static conditions by a sorbent based on a derivative of phytic acid fabricated from rice production waste are presented. It is shown that when the temperature is raised from 20 to 60°C, the sorption capacity of the sorbent based on phytic acid increases over the period of sorption and within 180 min reaches values of 1.4 mmol g-1 for Co2+ ions and 1.3 mmol g-1 for Ni2+ ions. It is established that for the investigated range of temperatures, order n of the sorption of Co2+ and Ni2+ ions is frame is best described by a kinetic model of a pseudo-second order, as is indicated by respective correlation coefficients.

Abscisic acid and the accumulation, biological activity and metabolism of four derivatives of [3H] gibberellin A1 in barley aleurone layers

International Nuclear Information System (INIS)

Stolp, C.F.; Nadeau, R.; Rappaport, L.

1977-01-01

Tritiated GA 1 and four of its synthetic derivatives were studied in relation to their biological activity, uptake and metabolism by barley alcurone layers. Incubation was done in the presence and absence of abscisic acid (ABA). Tentative identification of some of the metabolites was made by TLC and GLC radiocounting of the metabolite and its acid hydrolyzed derivative. Only GA 1 promoted α-amylase synthesis. Uptake ranged from 20 to 42%, varying with the derivative. ABA enhanced uptake of [ 3 H] GA 1 and [ 3 H] pseudoGA 1 and inhibited uptake of [ 3 H] ketoGA 1 , the Wagner-Meerwein rearrangement product of [ 3 H]GA 1 . Uptake of [ 3 H] GA 1 methyl ester ([ 3 H] GA 1 -Me) and [ 3 H] dihydroGA 1 was unaffected by ABA. [ 3 H] GA 1 was converted to an amphoteric GA 1 derivative [ 3 H] amphoGA 1 ) and [ 3 H] GA 1 -glycosyl ester. GA 1 -Me was metabolized to four products, all of them GA 1 derivatives including an apparent amphoteric GA 1 derivative. DihydroGA 1 was quite stable; only one metabolite was produced in sufficient yield to analyze. This product did not cochromatograph with either of the expected acid hydrolyzed epimers of [ 3 H] - dihydroGA 1 . [ 3 H] ketoGA 1 was readily metabolized to one product, probably the glycoside. [ 3 H] pseudoGA 1 remained essentially unmetabolized. Metabolism of all compounds tested was not dramatically affected by ABA. Surprisingly, no metabolites from hydroxylation at the 2-position were found. (auth.)

Sesquiterpenes, flavonoids, shikimic acid derivatives and pyrrolizidine alkaloids from Senecio kingii Hook.

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Ruiz-Vásquez, Liliana; Reina, Matías; López-Rodríguez, M; Giménez, Cristina; Cabrera, Raimundo; Cuadra, Pedro; Fajardo, Víctor; González-Coloma, Azucena

2015-09-01

Twenty-four compounds including eleven eremophilanolides (1-11), one eremophilane (13), five shikimic acid derivatives (14-18), six flavonoids (19-24), and the macrocyclic unsaturated pyrrolizidine alkaloid integerrimine (25) were isolated from Senecio kingii, an endemic species from the Magallanes Region (Chile). Compounds 3, 5, 6, 8-11 and 13-18 have not been previously reported as natural products. Their molecular structures were determined by NMR spectroscopic analysis and comparison with published NMR data. An X-ray-analysis of compound 3 has been performed. Their insecticidal and antifungal activities were tested, being compound 3 the strongest insect antifeedant. Compounds 6, 9 and 18 were moderate antifungals. Published by Elsevier Ltd.

Dehydroabietic Acid Derivative QC4 Induces Gastric Cancer Cell Death via Oncosis and Apoptosis

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Dongjun Luo

2016-01-01

Full Text Available Aim. QC4 is the derivative of rosin’s main components dehydroabietic acid (DHA. We investigated the cytotoxic effect of QC4 on gastric cancer cells and revealed the mechanisms beneath the induction of cell death. Methods. The cytotoxic effect of QC4 on gastric cancer cells was evaluated by CCK-8 assay and flow cytometry. The underlying mechanisms were tested by administration of cell death related inhibitors and detection of apoptotic and oncosis related proteins. Cytomembrane integrity and organelles damage were confirmed by lactate dehydrogenase (LDH leakage assay, mitochondrial function test, and cytosolic free Ca2+ concentration detection. Results. QC4 inhibited cell proliferation dose- and time-dependently and destroyed cell membrane integrity, activated calpain-1 autolysis, and induced apoptotic protein cleavage in gastric cancer cells. The detection of decreased ATP and mitochondrial membrane potential, ROS accumulation, and cytosolic free Ca2+ elevation confirmed organelles damage in QC4-treated gastric cancer cells. Conclusions. DHA derivative QC4 induced the damage of cytomembrane and organelles which finally lead to oncosis and apoptosis in gastric cancer cells. Therefore, as a derivative of plant derived small molecule DHA, QC4 might become a promising agent in gastric cancer therapy.

A novel colorimetric probe derived from isonicotic acid hydrazide for copper (II) determination based on internal charge transfer (ICT).

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Liu, Qing; Fei, Qiang; Fei, Yanqun; Fan, Qian; Shan, Hongyan; Feng, Guodong; Huan, Yanfu

2015-12-05

A novel isonicotic acid hydrazide Schiff base derivative N'-(3,5-di-tert-butyl-2-hydroxy-benzylidene) isonicotinohydrazide (DHIH) has been synthesized and developed as a high selective and sensitive colorimetric probe for Cu(2+) determination. Addition of Cu(2+) to the solution of DHIH resulted in a rapid color change from colorless to yellow together with an obvious new absorption band appeared at the range of 400-440 nm by forming a 1:1 complex. Experimental results indicated that the DHIH could provide absorption response to Cu(2+) with a linear dynamic range from 1.0×10(-5) to 1.0×10(-4)mol/L. The detection limit of Cu(2+) was 5.24×10(-7)mol/L with good tolerance of other metal ions. Copyright © 2015 Elsevier B.V. All rights reserved.

Crystal structures of seven molecular salts derived from benzylamine and organic acidic components

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Wen, Xianhong; Jin, Xiunan; Lv, Chengcai; Jin, Shouwen; Zheng, Xiuqing; Liu, Bin; Wang, Daqi; Guo, Ming; Xu, Weiqiang

2017-07-01

Cocrystallization of the commonly available organic amine, benzylamine, with a series of organic acids gave a total of seven molecular salts with the compositions: (benzylamine): (p-toluenesulfonic acid) (1) [(HL)+ · (tsa-)], (benzylamine): (o-nitrobenzoic acid) (2) [(HL+) · (onba)-], (benzylamine): (3,4-methylenedioxybenzoic acid) (3) [(HL+) · (mdba-)], (benzylamine): (mandelic acid) (4) [(HL+) · (mda-)], (benzylamine): (5-bromosalicylic acid)2(5) [(HL+) · (bsac-) · (Hbsac)], (benzylamine): (m-phthalic acid) (6) [(HL+) · (Hmpta-)], and (benzylamine)2: (trimesic acid) (7) [(HL+)2 · (Htma2-)]. The seven salts have been characterised by X-ray diffraction technique, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the seven investigated crystals the NH2 groups in the benzylamine moieties are protonated when the organic acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted Nsbnd H⋯O hydrogen bond formation between the ammonium and the deprotonated acidic groups. Except the Nsbnd H⋯O hydrogen bond, the Osbnd H⋯O hydrogen bonds (charge assisted or neutral) were also found at the salts 4-7. Further analysis of the crystal packing of the salts indicated that a different family of additional CHsbnd O/CH2sbnd O, CHsbnd π/CH2sbnd π, Osbnd O, and Osbnd Cπ associations contribute to the stabilization and expansion of the total high-dimensional (2D-3D) framework structures. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical supramolecular synthons, such as R42(8), R43(10) and R44(12), usually observed in organic solids of organic acids with amine, were again shown to be involved in constructing most of these hydrogen bonding networks.

Self-assembling properties of lactic acid derivative with several ester linkages in the molecular core

Czech Academy of Sciences Publication Activity Database

Pramanik, A.; Das, M.K.; Das, B.; Hamplová, Věra; Kašpar, Miroslav; Bubnov, Alexej

2015-01-01

Roč. 88, č. 7 (2015), s. 745-757 ISSN 0141-1594 R&D Projects: GA ČR GA13-14133S; GA MŠk(CZ) LD14007 Grant - others:AVČR(CZ) M100101204; AV ČR(CZ) M100101211 Institutional support: RVO:68378271 Keywords : lactic acid derivative * ferroelectric liquid crystal * self-assembling * spontaneous polarization * birefringence * phase transition Subject RIV: JJ - Other Materials Impact factor: 0.858, year: 2015

A systems approach for discovering linoleic acid derivatives that potentially mediate pain and itch

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Ramsden, Christopher E.; Domenichiello, Anthony F.; Yuan, Zhi-Xin; Sapio, Matthew R.; Keyes, Gregory S.; Mishra, Santosh K.; Gross, Jacklyn R.; Majchrzak-Hong, Sharon; Zamora, Daisy; Horowitz, Mark S.; Davis, John M.; Sorokin, Alexander V.; Dey, Amit; LaPaglia, Danielle M.; Wheeler, Joshua J.; Vasko, Michael R.; Mehta, Nehal N.; Mannes, Andrew J.; Iadarola, Michael J.

2018-01-01

Chronic pain and itch are common hypersensitivity syndromes that are affected by endogenous mediators. We applied a systems-based, translational approach to predict, discover, and characterize mediators of pain and itch that are regulated by diet and inflammation. Profiling of tissue-specific precursor abundance and biosynthetic gene expression predicted that inflamed skin would be abundant in four previously unknown 11-hydroxy-epoxy-or 11-keto-epoxy-octadecenoate linoleic acid derivatives and four previously identified 9- or 13-hydroxy-epoxy- or 9- or 13-keto-epoxy-octadecenoate linoleic acid derivatives. All of these mediators were confirmed to be abundant in rat and human skin by mass spectrometry. However, only the two 11-hydroxy-epoxy-octadecenoates sensitized rat dorsal root ganglion neurons to release more calcitonin gene–related peptide (CGRP), which is involved in pain transmission, in response to low pH (which mimics an inflammatory state) or capsaicin (which activates ion channels involved in nociception). The two 11-hydroxy-epoxy-octadecenoates share a 3-hydroxy-Z-pentenyl-E-epoxide moiety, thus suggesting that this substructure could mediate nociceptor sensitization. In rats, intradermal hind paw injection of 11-hydroxy-12,13-trans-epoxy-(9Z)-octadecenoate elicited C-fiber–mediated sensitivity to thermal pain. In a randomized trial testing adjunctive strategies to manage refractory chronic headaches, reducing the dietary intake of linoleic acid was associated with decreases in plasma 11-hydroxy-12,13-trans-epoxy-(9Z)-octadecenoate, which correlated with clinical pain reduction. Human psoriatic skin had 30-fold higher 9-keto-12,13-trans-epoxy-(10E)-octadecenoate compared to control skin, and intradermal injection of this compound induced itch-related scratching behavior in mice. Collectively, these findings define a family of endogenous mediators with potential roles in pain and itch. PMID:28831021

Photo-cross-linked poly(thioether-co-carbonate) networks derived from the natural product quinic acid.

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Link, Lauren A; Lonnecker, Alexander T; Hearon, Keith; Maher, Cameron A; Raymond, Jeffery E; Wooley, Karen L

2014-10-22

Polycarbonate networks derived from the natural product quinic acid that can potentially return to their natural building blocks upon hydrolytic degradation are described herein. Solvent-free thiol-ene chemistry was utilized in the copolymerization of tris(alloc)quinic acid and a variety of multifunctional thiol monomers to obtain poly(thioether-co-carbonate) networks with a wide range of achievable thermomechanical properties including glass transition temperatures from -18 to +65 °C and rubbery moduli from 3.8 to 20 MPa. The network containing 1,2-ethanedithiol expressed an average toughness at 25 and 63 °C of 1.08 and 2.35 MJ/m(3), respectively, and an order-of-magnitude increase in the average toughness at 37 °C of 15.56 MJ/m(3).

2-Furoylmethyl amino acids as indicators of Maillard reaction during the elaboration of black garlic.

Science.gov (United States)

Ríos-Ríos, Karina L; Vázquez-Barrios, M Estela; Gaytán-Martínez, Marcela; Olano, Agustín; Montilla, Antonia; Villamiel, Mar

2018-02-01

This study reports the formation of 2-furomethyl-amino acids (2-FM-AA) as indicators of Maillard reaction (MR) in black garlic elaboration, followed by the determination of furosine by ion-pair RP-HPLC-UV. The method was assessed for accuracy, repeatability and detection and quantitation limits indicating its adequacy. Traditional procedure of black garlic obtainment and the inclusion of convective drying (CDP) and ohmic heating (OHP) were assayed. For comparison purposes, three commercial black garlic samples were used. Together with furosine (2-FM-lysine), 2-furoylmethyl-γ-aminobutyric acid and 2-FM-arginine were detected. Levels of furosine were higher in CDP (46.6-110.1mg/100g protein) than in OHP (13.7-42.0mg/100g protein) samples, probably due to the most severe processing conditions used in the former. These results highlight the suitability of 2-FM-AA as chemical indicators to monitor the process of black garlic elaboration in order to obtain high quality products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hydroxybenzoic Acid Derivatives as Dual-Target Ligands: Mitochondriotropic Antioxidants and Cholinesterase Inhibitors.

Science.gov (United States)

Oliveira, Catarina; Cagide, Fernando; Teixeira, José; Amorim, Ricardo; Sequeira, Lisa; Mesiti, Francesco; Silva, Tiago; Garrido, Jorge; Remião, Fernando; Vilar, Santiago; Uriarte, Eugenio; Oliveira, Paulo J; Borges, Fernanda

2018-01-01

Alzheimer's disease (AD) is a multifactorial age-related disease associated with oxidative stress (OS) and impaired cholinergic transmission. Accordingly, targeting mitochondrial OS and restoring cholinergic transmission can be an effective therapeutic strategy toward AD. Herein, we report for the first time dual-target hydroxybenzoic acid (HBAc) derivatives acting as mitochondriotropic antioxidants and cholinesterase (ChE) inhibitors. The studies were performed with two mitochondriotropic antioxidants AntiOxBEN 1 (catechol derivative), and AntiOxBEN 2 (pyrogallol derivative) and compounds 15-18 , which have longer spacers. Compounds AntiOxBEN 1 and 15 , with a shorter carbon chain spacer (six- and eight-carbon) were shown to be potent antioxidants and BChE inhibitors (IC 50 = 85 ± 5 and 106 ± 5 nM, respectively), while compounds 17 and 18 with a 10-carbon chain were more effective AChE inhibitors (IC 50 = 7.7 ± 0.4 and 7.2 ± 0.5 μM, respectively). Interestingly, molecular modeling data pointed toward bifunctional ChEs inhibitors. The most promising ChE inhibitors acted by a non-competitive mechanism. In general, with exception of compounds 15 and 17 , no cytotoxic effects were observed in differentiated human neuroblastoma (SH-SY5Y) and human hepatocarcinoma (HepG2) cells, while Aβ-induced cytotoxicity was significantly prevented by the new dual-target HBAc derivatives. Overall, due to its BChE selectivity, favorable toxicological profile, neuroprotective activity and drug-like properties, which suggested blood-brain barrier (BBB) permeability, the mitochondriotropic antioxidant AntiOxBEN 1 is considered a valid lead candidate for the development of dual acting drugs for AD and other mitochondrial OS-related diseases.