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Sample records for demonstrated antimicrobial activity

  1. Antimicrobial Activity.

    Science.gov (United States)

    2016-01-01

    Natural products of higher plants may possess a new source of antimicrobial agents with possibly novel mechanisms of action. They are effective in the treatment of infectious diseases while simultaneously mitigating many of the side effects that are often associated with conventional antimicrobials. A method using scanning electron microscope (SEM) to study the morphology of the bacterial and fungal microbes and thus determining antimicrobial activity is presented in the chapter.

  2. Cover Your Cough! A Short and Simple Activity to Demonstrate the Antimicrobial Effect of Desiccation

    Directory of Open Access Journals (Sweden)

    Jennifer Cook Easterwood

    2013-08-01

    Full Text Available Many undergraduate microbiology laboratory manuals include exercises demonstrating the antimicrobial effects of physical agents, such as UV light and heat, and chemical agents, such as disinfectants and antibiotics (3, 4. There is, however, a lack of exercises examining the effects of desiccation on bacterial growth and survival. This particular form of antimicrobial control is especially relevant today with an increased emphasis on coughing and sneezing into one’s sleeve or a tissue, where microbes will not contaminate hands and will eventually desiccate and die (2. Desiccation can have bacteriostatic or bactericidal effects depending on the species, the material on which the organism has desiccated, and the length of time. The absence of water can damage many cellular components, including enzymes, nucleic acids, and cell membranes (1. However, many prokaryotes have some degree of resistance to desiccation, with Escherichia coli surviving around 24 hours and Bacillus species surviving upwards of 300 years, though these numbers can vary due to a number of confounding factors (5. Some of these factors include the method by which desiccation occurred, whether desiccation occurred in a natural or laboratory situation, and the species itself (5. To address the effects of desiccation on bacterial growth and survival, a short, simple exercise was developed. By inoculating various materials with bacterial cultures and allowing them to air-dry for 24 hours, students can visualize the effects of desiccation by analyzing the growth, or lack thereof, when organisms are transferred to nutrient agar plates. This exercise has been used in a health professions microbiology course as well as a microbiology course for biology and biochemistry majors. It is short enough to be conducted during a standard lecture period or during a longer laboratory period in conjunction with other experiments demonstrating the effectiveness of physical agents on microbial

  3. Bovine CCL28 Mediates Chemotaxis via CCR10 and Demonstrates Direct Antimicrobial Activity against Mastitis Causing Bacteria.

    Science.gov (United States)

    Pallister, Kyler B; Mason, Sara; Nygaard, Tyler K; Liu, Bin; Griffith, Shannon; Jones, Jennifer; Linderman, Susanne; Hughes, Melissa; Erickson, David; Voyich, Jovanka M; Davis, Mary F; Wilson, Eric

    2015-01-01

    In addition to the well characterized function of chemokines in mediating the homing and accumulation of leukocytes to tissues, some chemokines also exhibit potent antimicrobial activity. Little is known of the potential role of chemokines in bovine mammary gland health and disease. The chemokine CCL28 has previously been shown to play a key role in the homing and accumulation of IgA antibody secreting cells to the lactating murine mammary gland. CCL28 has also been shown to act as an antimicrobial peptide with activity demonstrated against a wide range of pathogens including bacteria, fungi and protozoans. Here we describe the cloning and function of bovine CCL28 and document the concentration of this chemokine in bovine milk. Bovine CCL28 was shown to mediate cellular chemotaxis via the CCR10 chemokine receptor and exhibited antimicrobial activity against a variety of bovine mastitis causing organisms. The concentration of bovine CCL28 in milk was found to be highly correlated with the lactation cycle. Highest concentrations of CCL28 were observed soon after parturition, with levels decreasing over time. These results suggest a potential role for CCL28 in the prevention/resolution of bovine mastitis.

  4. Bovine CCL28 Mediates Chemotaxis via CCR10 and Demonstrates Direct Antimicrobial Activity against Mastitis Causing Bacteria.

    Directory of Open Access Journals (Sweden)

    Kyler B Pallister

    Full Text Available In addition to the well characterized function of chemokines in mediating the homing and accumulation of leukocytes to tissues, some chemokines also exhibit potent antimicrobial activity. Little is known of the potential role of chemokines in bovine mammary gland health and disease. The chemokine CCL28 has previously been shown to play a key role in the homing and accumulation of IgA antibody secreting cells to the lactating murine mammary gland. CCL28 has also been shown to act as an antimicrobial peptide with activity demonstrated against a wide range of pathogens including bacteria, fungi and protozoans. Here we describe the cloning and function of bovine CCL28 and document the concentration of this chemokine in bovine milk. Bovine CCL28 was shown to mediate cellular chemotaxis via the CCR10 chemokine receptor and exhibited antimicrobial activity against a variety of bovine mastitis causing organisms. The concentration of bovine CCL28 in milk was found to be highly correlated with the lactation cycle. Highest concentrations of CCL28 were observed soon after parturition, with levels decreasing over time. These results suggest a potential role for CCL28 in the prevention/resolution of bovine mastitis.

  5. Antimicrobial activity of Gymnema sylvestre leaf extract.

    Science.gov (United States)

    Satdive, R K; Abhilash, P; Fulzele, Devanand P

    2003-12-01

    The ethanolic extract of Gymnema sylvestre leaves demonstrated antimicrobial activity against Bacillus pumilis, B. subtilis, Pseudomonas aeruginosa and Staphylococcus aureus and inactivity against Proteus vulgaris and Escherichia coli.

  6. Antimicrobial activity of flavonoids.

    Science.gov (United States)

    Cushnie, T P Tim; Lamb, Andrew J

    2005-11-01

    Flavonoids are ubiquitous in photosynthesising cells and are commonly found in fruit, vegetables, nuts, seeds, stems, flowers, tea, wine, propolis and honey. For centuries, preparations containing these compounds as the principal physiologically active constituents have been used to treat human diseases. Increasingly, this class of natural products is becoming the subject of anti-infective research, and many groups have isolated and identified the structures of flavonoids possessing antifungal, antiviral and antibacterial activity. Moreover, several groups have demonstrated synergy between active flavonoids as well as between flavonoids and existing chemotherapeutics. Reports of activity in the field of antibacterial flavonoid research are widely conflicting, probably owing to inter- and intra-assay variation in susceptibility testing. However, several high-quality investigations have examined the relationship between flavonoid structure and antibacterial activity and these are in close agreement. In addition, numerous research groups have sought to elucidate the antibacterial mechanisms of action of selected flavonoids. The activity of quercetin, for example, has been at least partially attributed to inhibition of DNA gyrase. It has also been proposed that sophoraflavone G and (-)-epigallocatechin gallate inhibit cytoplasmic membrane function, and that licochalcones A and C inhibit energy metabolism. Other flavonoids whose mechanisms of action have been investigated include robinetin, myricetin, apigenin, rutin, galangin, 2,4,2'-trihydroxy-5'-methylchalcone and lonchocarpol A. These compounds represent novel leads, and future studies may allow the development of a pharmacologically acceptable antimicrobial agent or class of agents.

  7. [Antimicrobial activity of Calendula L. plants].

    Science.gov (United States)

    Radioza, S A; Iurchak, L D

    2007-01-01

    The sap of different organs of genus Calendula plant species has been studied for antimicrobial activity. The sap of racemes demonstrated the most expressed antimicrobial effect while that of the roots - the least one. Calendula species inhibited all tested pathogenic microorganisms, especially Pseudomonas syringae, P. fluorescens, Xanthomonas campestris, Agrobacterium tumefaciens. Calendula suffruticosa was the most active to all investigated microorganisms.

  8. Human neutrophil antimicrobial activity.

    Science.gov (United States)

    Thomas, E L; Lehrer, R I; Rest, R F

    1988-01-01

    Polymorphonuclear neutrophilic leukocytes (PMNs) take up opsonized microorganisms into phagosomes that fuse with secretory granules in the PMN cytoplasm to form phagolysosomes. Killing and digestion of microorganisms take place within phagolysosomes. Antimicrobial activities in phagolysosomes are divided into two classes. Oxygen (O2)-dependent mechanisms are expressed when PMNs undergo the "respiratory burst." An NADPH oxidase in the phagolysosome membrane is activated and reduces O2 to superoxide (O2-). O2 reduction is the first step in a series of reactions that produce toxic oxidants. For example, .O2- dismutases to hydrogen peroxide (H2O2), and the azurophil granule enzyme myeloperoxidase catalyzes the oxidation of Cl- by H2O2 to yield hypochlorous acid (HOCl). The reaction of HOCl with ammonia and amines modulates the toxicity of this oxidant. O2-independent antimicrobial mechanisms include the activities of lysosomal proteases, other hydrolytic enzymes, and proteins and peptides that bind to microorganisms and disrupt essential processes or structural components. For example, the bactericidal/permeability-increasing protein, cathepsin G, and the defensins are released into phagolysosomes from the azurophil granules. Proposed mechanisms of action of neutrophil antimicrobial agents, their range of microbial targets, and their possible interactions within phagolysosomes are discussed.

  9. Antimicrobial Activity of Commercial Nanoparticles

    Science.gov (United States)

    Gajjar, Priyanka; Pettee, Brian; Britt, David W.; Huang, Wenjie; Johnson, William P.; Anderson, Anne J.

    2009-07-01

    Engineered nanoparticles are finding increased use in applications ranging from biosensors to prophylactic antimicrobials embedded in socks. The release of heavy metal-containing nanoparticles (NP) into the environment may be harmful to the efficacy of beneficial microbes that function in element cycling, pollutant degradation, and plant growth. Antimicrobial activity of commercial NP of Ag, CuO, and ZnO is demonstrated here against the beneficial soil microbe, Pseudomonas putida KT2440, which was modified to serve as a bioluminescent sentinel organism. "As manufactured" preparations of nano- Ag, -CuO, and -ZnO caused rapid, dose dependent loss of light output in the biosensor. Bulk equivalents of these products showed no inhibitory activity, indicating that particle size was determinant in activity.

  10. Antimicrobial activities of squalamine mimics.

    Science.gov (United States)

    Kikuchi, K; Bernard, E M; Sadownik, A; Regen, S L; Armstrong, D

    1997-07-01

    We investigated the antimicrobial properties of compounds with structural features that were designed to mimic those of squalamine, an antibiotic isolated from the stomach of the dogfish shark. The mimics, like squalamine, are sterol-polyamine conjugates. Unlike squalamine, the mimics were simple to prepare, at high yield, from readily available starting materials. Several squalamine mimics showed activity against gram-negative rods, gram-positive cocci including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and fungi. Some had little or no hemolytic activity. The hydrophobicity of the sterol backbone and the length and the cationic charge of the side chains appeared to be critical determinants of activity. One of the squalamine mimics, SM-7, was bactericidal against Escherichia coli, Pseudomonas aeruginosa, and S. aureus; its activity was decreased by divalent or monovalent cations and by bovine serum albumin. Subinhibitory concentrations of SM-7 markedly enhanced the antimicrobial activity of rifampin against gram-negative rods. These results suggest that the compounds may disrupt an outer membrane of gram-negative rods. Squalamine mimics are a new class of broad-spectrum antimicrobial agents. The antagonism of their activity by serum and albumin and their hemolytic properties may limit their use as systemic agents. The squalamine mimics, because of their potencies, broad spectra of antimicrobial activity, and potential for systemic toxicity, appear to be good candidates for development as topical antimicrobial agents.

  11. Antimicrobial activity of Securidaca longipedunculata.

    Science.gov (United States)

    Ajali, U; Chukwurah, B K C

    2004-11-01

    The folk herbal uses of Securidaca longipedunculata in the treatment of diarrhea, boils, gonorrhea, and cough prompted phytochemical analyses and antimicrobial activity screening of extracts of the root. Some flavonoids isolated showed activity against many micro-organisms. These flavonoids were isolated using chromatographic methods.

  12. Antimicrobial Activity of Resveratrol Analogues

    Directory of Open Access Journals (Sweden)

    Malik Chalal

    2014-06-01

    Full Text Available Stilbenes, especially resveratrol and its derivatives, have become famous for their positive effects on a wide range of medical disorders, as indicated by a huge number of published studies. A less investigated area of research is their antimicrobial properties. A series of 13 trans-resveratrol analogues was synthesized via Wittig or Heck reactions, and their antimicrobial activity assessed on two different grapevine pathogens responsible for severe diseases in the vineyard. The entire series, together with resveratrol, was first evaluated on the zoospore mobility and sporulation level of Plasmopara viticola (the oomycete responsible for downy mildew. Stilbenes displayed a spectrum of activity ranging from low to high. Six of them, including the most active ones, were subsequently tested on the development of Botrytis cinerea (fungus responsible for grey mold. The results obtained allowed us to identify the most active stilbenes against both grapevine pathogens, to compare the antimicrobial activity of the evaluated series of stilbenes, and to discuss the relationship between their chemical structure (number and position of methoxy and hydroxy groups and antimicrobial activity.

  13. Antimicrobial activities of squalamine mimics.

    OpenAIRE

    1997-01-01

    We investigated the antimicrobial properties of compounds with structural features that were designed to mimic those of squalamine, an antibiotic isolated from the stomach of the dogfish shark. The mimics, like squalamine, are sterol-polyamine conjugates. Unlike squalamine, the mimics were simple to prepare, at high yield, from readily available starting materials. Several squalamine mimics showed activity against gram-negative rods, gram-positive cocci including methicillin-resistant Staphyl...

  14. Antioxidant and antimicrobial activities of Shorea kunstleri

    Institute of Scientific and Technical Information of China (English)

    Siti Suria Daud; Muhammad Taher; Deny Susanti

    2014-01-01

    Objective:To evaluate antioxidant and antimicrobial activities of stembark of Shorea kunstleri (S. kunstleri) together with analysis of phytochemical and total phenolic contents. Methods:Extraction was conducted with different solvent polarity of n-hexane, dichloromethane (DCM) and methanol by using Soxhlet extraction. Total phenolic content was determined using Folin-Ciocalteu method. Free radical scavenging activity and inhibition of lipid peroxidation were evaluated with DPPH radical scavenging and ferric thiocyanate assays, respectively. Antimicrobial activities were performed using disc diffusion method, minimum inhibition concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration. Results:S. kunstleri stembark extracts revealed presence of steroids, terpenoids, saponins, flavonoids, and phenolic compounds. Methanol extract exhibited the highest total phenolic content and free radical scavenging activity resulting in phenolic content of (8.340±0.003) g GAE/100 g of extract and (95.90±1.07)% DPPH inhibition (IC50 value of 18.6 µg/mL), respectively. Ferric thiocyanate assay of n-hexane, DCM, and methanol extracts indicated lipid peroxidation inhibitory activity of (74.20±0.35)%, (74.00±0.10)%, and (72.80±0.27)%, respectively. In antimicrobial and antifungal tests, methanol extract showed inhibition against Staphylococcus aureus (S. aureus), Candida albicans, and Candida tropicalis with inhibition zones of 10-12, 18-22, and 18-19 mm, respectively. The MIC test of methanol extract showed highest inhibition against Candida albicans and S. aureus (0.04 and 0.08 mg/mL, respectively) while DCM extract exhibited the highest activity towards Candida tropicalis (MIC value of 0.63 mg/mL). Taken together, MBC test of methanol extract strongly demonstrated bactericidal effect against S. aureus with MBC value of 0.08 mg/mL. Conclusions:The study demonstrated that stembark extracts of S. kunstleri possessed antioxidant and

  15. Antioxidant and antimicrobial activities of Shorea kunstleri

    Directory of Open Access Journals (Sweden)

    Siti Suria Daud

    2014-08-01

    Full Text Available Objective: To evaluate antioxidant and antimicrobial activities of stembark of Shorea kunstleri (S. kunstleri together with analysis of phytochemical and total phenolic contents. Methods: Extraction was conducted with different solvent polarity of n-hexane, dichloromethane (DCM and methanol by using Soxhlet extraction. Total phenolic content was determined using Folin-Ciocalteu method. Free radical scavenging activity and inhibition of lipid peroxidation were evaluated with DPPH radical scavenging and ferric thiocyanate assays, respectively. Antimicrobial activities were performed using disc diffusion method, minimum inhibition concentration (MIC, minimum bactericidal concentration (MBC, and minimum fungicidal concentration. Results: S. kunstleri stembark extracts revealed presence of steroids, terpenoids, saponins, flavonoids, and phenolic compounds. Methanol extract exhibited the highest total phenolic content and free radical scavenging activity resulting in phenolic content of (8.340±0.003 g GAE/100 g of extract and (95.90±1.07% DPPH inhibition (IC50 value of 18.6 µg/mL, respectively. Ferric thiocyanate assay of n-hexane, DCM, and methanol extracts indicated lipid peroxidation inhibitory activity of (74.20±0.35%, (74.00±0.10%, and (72.80±0.27%, respectively. In antimicrobial and antifungal tests, methanol extract showed inhibition against Staphylococcus aureus (S. aureus, Candida albicans, and Candida tropicalis with inhibition zones of 10-12, 18-22, and 18-19 mm, respectively. The MIC test of methanol extract showed highest inhibition against Candida albicans and S. aureus (0.04 and 0.08 mg/mL, respectively while DCM extract exhibited the highest activity towards Candida tropicalis (MIC value of 0.63 mg/mL. Taken together, MBC test of methanol extract strongly demonstrated bactericidal effect against S. aureus with MBC value of 0.08 mg/mL. Conclusions: The study demonstrated that stembark extracts of S. kunstleri possessed antioxidant

  16. ANTIMICROBIAL ACTIVITY OF EXTRACTS FROM ECUADORIAN LICHENS.

    Science.gov (United States)

    Matvieieva, N A; Pasichnyk, L A; Zhytkevych, N V; Jacinto, Pabón Garcés Galo; Pidgorskyi, V S

    2015-01-01

    Antimicrobial activity of the ethanolic, isopropanolic, acetone, DMSO and aqueous extracts of the two lichen species from Ecuadorian highland, Usnea sp. and Stereocaulon sp. were explored in vitro against bacteria Bacillus subtilis, Escherichia coli and Staphylococcus aureus by the disc-diffusion method. Also the minimal inhibitory concentration (MIC) was determined. The strongest antimicrobial activity was found in DMSO extract of Usnea sp. compared to antibacterial activity of ciprfloxacin and cefazolin antibiotics. The inhibition zone was 28 mm, 30 mm, 31mm (DMSO extract, ciprfloxacin and cefazolin respectively) in case of B. subtilis usage as the test bacteria. MIC value for Usnea sp. and Stereocaulon sp. DMSO extracts was 0.4 mg/ml. E. coli was resistant to all kinds of extracts. The S. aureus sensitivity to lichen DMSO extracts was comparable to sensitivity of these microorganisms to tetracycline and vancomycin. Thereby, most kinds of extracts (ethanol, isopropanol, hexane, DMSO and acetone solvents) from Ecuadorian lichens Usnea sp. and Stereocaulon sp. with the exception of aqueous Stereocaulon sp. extracts possessed antibacterial activity against B. subtilis. DMSO lichen extracts had also antimicrobial activity against S. aureus. At the same time the extracts studied didn't demonstrate antibacterial activity against the representatives of the most common and harmful phytopathogenic bacteria tested. Further investigations of Ecuadorian lichens especially study of plants collected from extremal highland biotops can be very important in study of possibility of treatment of numerous diseases caused by pathogenic microorganisms.

  17. Magnesium Based Materials and their Antimicrobial Activity

    Science.gov (United States)

    Robinson, Duane Allan

    The overall goals of this body of work were to characterize the antimicrobial properties of magnesium (Mg) metal and nano-magnesium oxide (nMgO) in vitro, to evaluate the in vitro cytotoxicity of Mg metal, and to incorporate MgO nanoparticles into a polymeric implant coating and evaluate its in vitro antimicrobial properties. In the course of this work it was found that Mg metal, Mg-mesh, and nMgO have in vitro antimicrobial properties that are similar to a bactericidal antibiotic. For Mg metal, the mechanism of this activity appears to be related to an increase in pH (i.e. a more alkaline environment) and not an increase in Mg2+. Given that Mg-mesh is a Mg metal powder, the assumption is that it has the same mechanism of activity as Mg metal. The mechanism of activity for nMgO remains to be elucidated and may be related to a combination of interaction of the nanoparticles with the bacteria and the alkaline pH. It was further demonstrated that supernatants from suspensions of Mg-mesh and nMgO had the same antimicrobial effect as was noted when the particles were used. The supernatant from Mg-mesh and nMgO was also noted to prevent biofilm formation for two Staphylococcus strains. Finally, poly-epsilon-caprolactone (PCL) composites of Mg-mesh (PCL+Mg-mesh) and nMgO (PCL+nMgO) were produced. Coatings applied to screws inhibited growth of Escherichia coli and Pseudomonas aeruginosa and in thin disc format inhibited the growth of Staphylococcus aureus in addition to the E. coli and P. aeruginosa. Pure Mg metal was noted to have some cytotoxic effect on murine fibroblast and osteoblast cell lines, although this effect needs to be characterized further. To address the need for an in vivo model for evaluating implant associated infections, a new closed fracture osteomyelitis model in the femur of the rat was developed. Magnesium, a readily available and inexpensive metal was shown to have antimicrobial properties that appear to be related to its corrosion products and

  18. Antimicrobial Activities of Dorema Auchri

    Directory of Open Access Journals (Sweden)

    A Sharifi

    2011-01-01

    Full Text Available Introduction & Objective: Due to emerging of resistance of microorganisms to antibiotics, investigations for novel antimicrobial agents have always been one of the major preoccupations of the medical society. Traditional medicine systems have played an important role during human evolution and development. Today, a number of medical herbs around the world have been studied for their medicinal activities. Amongst the several herbal medicine used as a medicine, Dorema auchri is yet another potent herbal medicine which has not been extensively studied for the medicinal uses in comparison with other herbal medicine. Dorema auchri has a long history of use as a sore and food additive in Yasuj, Iran. However, not much scientific work has been conducted on Dorema auchri antimicrobial activities. The present study aimed to study the antimicrobial properties of Dorema auchri on some pathogen microorganisms. Materials & Methods: In the present study was conducted at Yasuj University of Medical Sciences in 2009. After collection and preparation of hydro alcoholic extract of Dorena auchri, the extract was used to study its activities against human pathogen microorganisms (overall 10 microorganisms. The determination of minimal inhibitory concentration (MIC and minimum lethal concentration were evaluated for this extract. The antimicrobial potent of Dorema auchri extract was compared with commercial antibiotics. Each experiment was done three times and collected data were analyzed by SPSS using ANOVA and Chi-Square tests. Results: Findings of this study showed that in 10 mg/ml concentration, all bacteria were resistant to Dorema auchri extract. In 20 mg/ml concentration, only Staphylococcus areus and Staphylococcus epidermis showed zone of inhibition (ZOI 10 mm and 13 mm respectively. In 40 mg/ml concentration, the maximum ZOI was 15 mm in Staphylococcus areus and 80 mg/ml concentration, the maximum ZOI was 20 mm in Staphylococcus areus. The acceptable MIC

  19. Antimicrobial activity of some Alnus species.

    Science.gov (United States)

    Altınyay, Ç; Eryılmaz, M; Yazgan, A N; Sever Yılmaz, B; Altun, M L

    2015-12-01

    The increasing prevalence of resistant microorganisms forced scientists to find new antimicrobial substances from different sources like medicinal plants. The aim of this study was to determine the antimicrobial activities of leaf extracts of some Alnus sp. against some bacteria and a yeast. Aqueous and ethanolic leaf extracts of A. glutinosa subsp. glutinosa, A. orientalis var. orientalis, A. orientalis var. pubescens were screened for their antimicrobial activities against Staphylococcus aureus ATCC 25923, S. aureus ATCC 43300 (MRSA), Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Candida albicans ATCC 10231. Broth dilution method was used to determine the antimicrobial activities of plant extracts. Ethanolic extracts of tested species exhibited better antimicrobial activity than aqueous extracts. Ethanolic extracts of tested species possessed activity having MIC values of 0.125-0.250 mg/ml against the tested microorganisms. No antibacterial activity was observed against B. subtilis, E. coli, P. aeruginosa for all the aqueous extracts. Except these aqueous extracts, the others possessed activity having MIC value of 1.000 mg/ml against the tested microorganisms. To our knowledge, this is the first investigation on the evaluation of antimicrobial activities on aqueous and ethanolic leaf extracts of these species. This study provides significant information about antimicrobial activities of leaf extracts of A. glutinosa subsp. glutinosa, A. orientalis var. orientalis, A. orientalis var. pubescens. It is conceivable that one of the reason for the usage of Alnus glutinosa, in treatment of wound healing in folk medicine, is because of its antimicrobial activity.

  20. Synthesis and antimicrobial activity of squalamine analogue.

    Science.gov (United States)

    Kim, H S; Choi, B S; Kwon, K C; Lee, S O; Kwak, H J; Lee, C H

    2000-08-01

    Synthesis and antimicrobial activity of squalamine analogue 2 are reported. The synthesis of 2 was accomplished from bisnoralcohol 3. The spermidine moiety was introduced via reductive amination of an appropriately functionalized 3beta-aminosterol with spermidinyl aldehyde 17 utilizing sodium triacetoxyborohydride as the reducing agent. Compound 2 shows weaker antimicrobial activity than squalamine.

  1. Peptides with Dual Antimicrobial and Anticancer Activities

    Science.gov (United States)

    Felício, Mário R.; Silva, Osmar N.; Gonçalves, Sônia; Santos, Nuno C.; Franco, Octávio L.

    2017-02-01

    In recent years, the number of people suffering from cancer and multi-resistant infections has increased, such that both diseases are already seen as current and future major causes of death. Moreover, chronic infections are one of the main causes of cancer, due to the instability in the immune system that allows cancer cells to proliferate. Likewise, the physical debility associated with cancer or with anticancer therapy itself often paves the way for opportunistic infections. It is urgent to develop new therapeutic methods, with higher efficiency and lower side effects. Antimicrobial peptides (AMPs) are found in the innate immune system of a wide range of organisms. Identified as the most promising alternative to conventional molecules used nowadays against infections, some of them have been shown to have dual activity, both as antimicrobial and anticancer peptides (ACPs). Highly cationic and amphipathic, they have demonstrated efficacy against both conditions, with the number of nature-driven or synthetically designed peptides increasing year by year. With similar properties, AMPs that can also act as ACPs are viewed as future chemotherapeutic drugs, with the advantage of low propensity to resistance, which started this paradigm in the pharmaceutical market. These peptides have already been described as molecules presenting killing mechanisms at the membrane level, but also acting towards intracellular targets, which increases their success comparatively to specific one-target drugs. This review will approach the desirable characteristics of small peptides that demonstrated dual activity against microbial infections and cancer, as well as the peptides engaged in clinical trials.

  2. Antimicrobial activity of some Iranian medicinal plants

    Directory of Open Access Journals (Sweden)

    Ghasemi Pirbalouti Abdollah

    2010-01-01

    Full Text Available The major aim of this study was to determine the antimicrobial activity of the extracts of eight plant species which are endemic in Iran. The antimicrobial activities of the extracts of eight Iranian traditional plants, including Hypericum scabrum, Myrtus communis, Pistachia atlantica, Arnebia euchroma, Salvia hydrangea, Satureja bachtiarica, Thymus daenensis and Kelussia odoratissima, were investigated against Escherichia coli O157:H7, Bacillus cereus, Listeria monocytogenes and Candida albicans by agar disc diffusion and serial dilution assays. Most of the extracts showed a relatively high antimicrobial activity against all the tested bacteria and fungi. Of the plants studied, the most active extracts were those obtained from the essential oils of M. communis and T. daenensis. The MIC values for active extract and essential oil ranged between 0.039 and 10 mg/ml. It can be said that the extract and essential oil of some medicinal plants could be used as natural antimicrobial agents in food preservation. .

  3. ANTIMICROBIAL ACTIVITY OF LACTIC ACID BACTERIAL ISOLATES

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    Utkarsha S. Shivsharan

    2013-08-01

    Full Text Available Micro-organisms have tendency to produce antimicrobial substances which show biological activity against other kind of micro-organisms. This phenomenon of bacterial antagonism is observed in lactic acid bacteria with competitive advantages. The lactic acid bacteria are commonly present in many fermented products, fruits and milk products. The variety of antimicrobial substances produced by lactic acid bacteria showing good inhibition capacity include production of lactic acid, acetic acid, hydrogen peroxide, carbon dioxide, diacetyl and bacteriocin. Bacteriocins produced by lactic acid bacteria are the subject of intense research because of their antimicrobial activity against food born bacteria such as Listeria monocytogenes, staphylococcus aureus, Bacillus cereus, Clostridium botulinum and several others .Bacteriocins may be bacteriostatic or bactericidal with narrow or broad range of activity. The main of the study was to study the antimicrobial activity of such lactic acid bacterial isolates.

  4. Antimicrobial activity of Gymnema sylvestre (Asclepiadaceae

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    Beverly C. David

    2013-01-01

    Conclusions: The dried scale leaves of G. sylvestre might represent a new antimicrobial source with stable, biologically active components that can establish a scientific base for the use in modern medicine.

  5. Antimicrobial activities, toxinogenic potential and sensitivity to ...

    African Journals Online (AJOL)

    SAM

    2014-08-27

    Aug 27, 2014 ... spoilage bacteria, yeasts and molds, toxinogenic potential and sensitivity to ... Key words: Bacillus, antimicrobial activities, toxins, antibiotic resistance. .... PCR detection of genes encoding a larvicidal protein (Cry1) in. Bacillus ...

  6. Antimicrobial activity of propolis against Streptococcus mutans

    African Journals Online (AJOL)

    USER

    2010-08-02

    Aug 2, 2010 ... Key words: Dental caries, antimicrobial activity, Apis mellifera, Streptococcus mutans, ethanol extract of propolis. ... of oral micro- organisms and inhibits cell adhesion as well as water .... A review: J. Peadiatric. Dent. 6: 79-. 83.

  7. Synthesis, characterization, antimicrobial activity and molecular ...

    African Journals Online (AJOL)

    Synthesis, characterization, antimicrobial activity and molecular .... The solid product was filtered, washed with ether (3 × 20 ... dimethyl sulfoxide (DMSO) to obtain 5120 mg/mL ...... catalysts for direct diastereo-and regioselective Mannich.

  8. Antimicrobial activity of Tridax procumbens leaf

    OpenAIRE

    S. Santhosh Kumar; John, R.; G.Lakshmi Narayanan

    2015-01-01

    Estimation of the antimicrobial property of Tridax procumbens’s leaf was carried out by the use of chloroform, petroleum ether, ethyl alcohol and hexaneas solvents. Leaf extract of Tridax procumbens obtained by soxhlet extractor, using the above mentioned solvents were examined against Escherichia coli, Bacillus subtilis, and Pseudomonas vulgaris. The antimicrobial activity of Tridax procumbens performed by using agarwell diffusion method showed a result showcasing an effective limit when as ...

  9. Gram-positive antimicrobial activity of amino acid-based hydrogels.

    Science.gov (United States)

    Irwansyah, I; Li, Yong-Qiang; Shi, Wenxiong; Qi, Dianpeng; Leow, Wan Ru; Tang, Mark B Y; Li, Shuzhou; Chen, Xiaodong

    2015-01-27

    Antimicrobial hydrogels are prepared based on the co-assembly of commercial Fmoc-phenylalanine and Fmoc-leucine, which act as the hydrogelator and antimicrobial building block, respectively. This co-assembled antimicrobial hydrogel is demonstrated to exhibit selective bactericidal activity for gram-positive bacteria while being biocompatible with normal mammalian cells, showing great potential as an antimicrobial coating for clinical anti-infective applications.

  10. Demonstration of Active Combustion Control

    Science.gov (United States)

    Lovett, Jeffrey A.; Teerlinck, Karen A.; Cohen, Jeffrey M.

    2008-01-01

    The primary objective of this effort was to demonstrate active control of combustion instabilities in a direct-injection gas turbine combustor that accurately simulates engine operating conditions and reproduces an engine-type instability. This report documents the second phase of a two-phase effort. The first phase involved the analysis of an instability observed in a developmental aeroengine and the design of a single-nozzle test rig to replicate that phenomenon. This was successfully completed in 2001 and is documented in the Phase I report. This second phase was directed toward demonstration of active control strategies to mitigate this instability and thereby demonstrate the viability of active control for aircraft engine combustors. This involved development of high-speed actuator technology, testing and analysis of how the actuation system was integrated with the combustion system, control algorithm development, and demonstration testing in the single-nozzle test rig. A 30 percent reduction in the amplitude of the high-frequency (570 Hz) instability was achieved using actuation systems and control algorithms developed within this effort. Even larger reductions were shown with a low-frequency (270 Hz) instability. This represents a unique achievement in the development and practical demonstration of active combustion control systems for gas turbine applications.

  11. Peptides with Dual Antimicrobial and Anticancer Activities

    Science.gov (United States)

    Felício, Mário R.; Silva, Osmar N.; Gonçalves, Sônia; Santos, Nuno C.; Franco, Octávio L.

    2017-01-01

    In recent years, the number of people suffering from cancer and multi-resistant infections has increased, such that both diseases are already seen as current and future major causes of death. Moreover, chronic infections are one of the main causes of cancer, due to the instability in the immune system that allows cancer cells to proliferate. Likewise, the physical debility associated with cancer or with anticancer therapy itself often paves the way for opportunistic infections. It is urgent to develop new therapeutic methods, with higher efficiency and lower side effects. Antimicrobial peptides (AMPs) are found in the innate immune system of a wide range of organisms. Identified as the most promising alternative to conventional molecules used nowadays against infections, some of them have been shown to have dual activity, both as antimicrobial and anticancer peptides (ACPs). Highly cationic and amphipathic, they have demonstrated efficacy against both conditions, with the number of nature-driven or synthetically designed peptides increasing year by year. With similar properties, AMPs that can also act as ACPs are viewed as future chemotherapeutic drugs, with the advantage of low propensity to resistance, which started this paradigm in the pharmaceutical market. These peptides have already been described as molecules presenting killing mechanisms at the membrane level, but also acting toward intracellular targets, which increases their success compartively to one-target specific drugs. This review will approach the desirable characteristics of small peptides that demonstrated dual activity against microbial infections and cancer, as well as the peptides engaged in clinical trials. PMID:28271058

  12. ANTIMICROBIAL ACTIVITY OF FICUS GLOMERATA LINN. BARK

    Directory of Open Access Journals (Sweden)

    Jagtap Supriya G.

    2012-05-01

    Full Text Available Ficus glomerata Linn. (Moraceae, commonly known as Ficus racemosa. A large deciduous tree distributed all over India and Ceylon, found throughout the year, grows in evergreen forest, moist localities, along the sides of ravines and banks of streams. Gular (Ficus glomerata Linn. is well known, commonly used plant in various disorders. It has been traditionally claimed to be useful in asthmatic condition, as an antitussive and anti-inflammatory. Successive soxhlet extractions of dried powdered bark were carried out using petroleum ether and methanol as a solvent. The antimicrobial activity of the extracts were tested in vitro against two different bacterial species Bacillus substilis and Escherichia coli by cup plate diffusion method were used in this investigation. The results of antimicrobial activity revealed that methanolic extract showed good activity as compared to petroleum ether extract. Methanolic extract is more potent towards gram - positive bacteria. The antimicrobial activities of the extracts were compared with standard antibiotics.

  13. Prediction of Antibacterial Activity from Physicochemical Properties of Antimicrobial Peptides

    NARCIS (Netherlands)

    de Sousa Pereira Simoes de Melo, Manuel; Ferre, Rafael; Feliu, Lidia; Bardaji, Eduard; Planas, Marta; Castanho, Miguel A. R. B.

    2011-01-01

    Consensus is gathering that antimicrobial peptides that exert their antibacterial action at the membrane level must reach a local concentration threshold to become active. Studies of peptide interaction with model membranes do identify such disruptive thresholds but demonstrations of the possible co

  14. The Antimicrobial Activity of Porphyrin Attached Polymers

    Science.gov (United States)

    Thompson, Lesley

    2008-03-01

    We are interested in testing the antimicrobial activity of a porphyrin that is attached to a polymer. The porphyrin (5-(4-carboxyphenyl)-10,15,20-tris-(4-pryridyl)) was synthesized from methyl 4-formyl benzoate, 4-pyridinecarboxaldehyde, and pyrrole and attached to a copolymer of polystyrene/poly(vinyl benzyl chloride), which was synthesized by free radical polymerization. The antimicrobial activity of the polymer-attached porphyrin was then determined for gram-negative E. Coli grown to 0.80 OD. In this procedure, glass slides were coated with polymer-attached porphyrin via dip-coating, and the E. Coli bacteria were plated in Luria Broth media. The plates were subsequently exposed to light overnight before they were incubated as porphyrins act as photo-sensitizers when irradiated with light. The polymer-attached porphyrin did exhibit antimicrobial activity and parameters that affect its efficiency will be discussed.

  15. Synthesis and Antimicrobial Activity of Silver-Doped Hydroxyapatite Nanoparticles

    Directory of Open Access Journals (Sweden)

    Carmen Steluta Ciobanu

    2013-01-01

    Full Text Available The synthesis of nanosized particles of Ag-doped hydroxyapatite with antibacterial properties is of great interest for the development of new biomedical applications. The aim of this study was the evaluation of Ca10−xAgx(PO46(OH2 nanoparticles (Ag:HAp-NPs for their antibacterial and antifungal activity. Resistance to antimicrobial agents by pathogenic bacteria has emerged in the recent years and became a major health problem. Here, we report a method for synthesizing Ag doped nanocrystalline hydroxyapatite. A silver-doped nanocrystalline hydroxyapatite was synthesized at 100°C in deionised water. Also, in this paper Ag:HAp-NPs are evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria and fungal strains. The specific antimicrobial activity revealed by the qualitative assay is demonstrating that our compounds are interacting differently with the microbial targets, probably due to the differences in the microbial wall structures.

  16. Synthesis, Characterization and Antimicrobial Activity of Mixed ...

    African Journals Online (AJOL)

    ADOWIE PERE

    antimicrobial activity while the Fe(II ) complex showed the least activity against the bacterial .... The elemental analysis results for carbon, hydrogen, nitrogen and oxygen found were very close to the ..... Shebl, M., Seleem, H.S., El-Shetary B.A..

  17. Protease Inhibitors from Plants with Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Yoonkyung Park

    2009-06-01

    Full Text Available Antimicrobial proteins (peptides are known to play important roles in the innate host defense mechanisms of most living organisms, including plants, insects, amphibians and mammals. They are also known to possess potent antibiotic activity against bacteria, fungi, and even certain viruses. Recently, the rapid emergence of microbial pathogens that are resistant to currently available antibiotics has triggered considerable interest in the isolation and investigation of the mode of action of antimicrobial proteins (peptides. Plants produce a variety of proteins (peptides that are involved in the defense against pathogens and invading organisms, including ribosome-inactivating proteins, lectins, protease inhibitors and antifungal peptides (proteins. Specially, the protease inhibitors can inhibit aspartic, serine and cysteine proteinases. Increased levels of trypsin and chymotrypsin inhibitors correlated with the plants resistance to the pathogen. Usually, the purification of antimicrobial proteins (peptides with protease inhibitor activity was accomplished by salt-extraction, ultrafiltration and C18 reverse phase chromatography, successfully. We discuss the relation between antimicrobial and anti-protease activity in this review. Protease inhibitors from plants potently inhibited the growth of a variety of pathogenic bacterial and fungal strains and are therefore excellent candidates for use as the lead compounds for the development of novel antimicrobial agents.

  18. Peptide consensus sequence determination for the enhancement of the antimicrobial activity and selectivity of antimicrobial peptides

    Science.gov (United States)

    Almaaytah, Ammar; Ajingi, Ya’u; Abualhaijaa, Ahmad; Tarazi, Shadi; Alshar’i, Nizar; Al-Balas, Qosay

    2017-01-01

    The rise of multidrug-resistant bacteria is causing a serious threat to the world’s human population. Recent reports have identified bacterial strains displaying pan drug resistance against antibiotics and generating fears among medical health specialists that humanity is on the dawn of entering a post-antibiotics era. Global research is currently focused on expanding the lifetime of current antibiotics and the development of new antimicrobial agents to tackle the problem of antimicrobial resistance. In the present study, we designed a novel consensus peptide named “Pepcon” through peptide consensus sequence determination among members of a highly homologous group of scorpion antimicrobial peptides. Members of this group were found to possess moderate antimicrobial activity with significant toxicity against mammalian cells. The aim of our design method was to generate a novel peptide with an enhanced antimicrobial potency and selectivity against microbial rather than mammalian cells. The results of our study revealed that the consensus peptide displayed potent antibacterial activities against a broad range of Gram-positive and Gram-negative bacteria. Our membrane permeation studies displayed that the peptide efficiently induced membrane damage and consequently led to cell death through the process of cell lysis. The microbial DNA binding assay of the peptide was found to be very weak suggesting that the peptide is not targeting the microbial DNA. Pepcon induced minimal cytotoxicity at the antimicrobial concentrations as the hemolytic activity was found to be zero at the minimal inhibitory concentrations (MICs). The results of our study demonstrate that the consensus peptide design strategy is efficient in generating peptides. PMID:28096686

  19. Antimicrobial Activity of Carbon-Based Nanoparticles

    Directory of Open Access Journals (Sweden)

    Solmaz Maleki Dizaj

    2015-03-01

    Full Text Available Due to the vast and inappropriate use of the antibiotics, microorganisms have begun to develop resistance to the commonly used antimicrobial agents. So therefore, development of the new and effective antimicrobial agents seems to be necessary. According to some recent reports, carbon-based nanomaterials such as fullerenes, carbon nanotubes (CNTs (especially single-walled carbon nanotubes (SWCNTs and graphene oxide (GO nanoparticles show potent antimicrobial properties. In present review, we have briefly summarized the antimicrobial activity of carbon-based nanoparticles together with their mechanism of action. Reviewed literature show that the size of carbon nanoparticles plays an important role in the inactivation of the microorganisms. As major mechanism, direct contact of microorganisms with carbon nanostructures seriously affects their cellular membrane integrity, metabolic processes and morphology. The antimicrobial activity of carbon-based nanostructures may interestingly be investigated in the near future owing to their high surface/volume ratio, large inner volume and other unique chemical and physical properties. In addition, application of functionalized carbon nanomaterials as carriers for the ordinary antibiotics possibly will decrease the associated resistance, enhance their bioavailability and provide their targeted delivery.

  20. Antimicrobial activity of marine organisms collected off the coast of South East India

    Digital Repository Service at National Institute of Oceanography (India)

    Rodrigues, E.; Tilvi, S.; Naik, C.G.

    the marine organisms demonstrated activity against one or more of microbes tested. Sigmadocia carnosa was the most active exhibiting a broad spectrum antimicrobial activity against each of the microbe tested with the exception of Fusarium species. Contrary...

  1. Antimicrobial activity of mangrove plant (Lumnitzera littorea)

    Institute of Scientific and Technical Information of China (English)

    Shahbudin Saad; Muhammad Taher; Deny Susanti; Haitham Qaralleh; Nurul Afifah Binti Abdul Rahim

    2011-01-01

    Objective:To investigate the antimicrobial activities ofn-hexane, ethyl acetate and methanol extracts of the leaves ofLumnitzera littorea (L. littorea) against six human pathogenic microbes. Methods: The antimicrobial activity was evaluated using disc diffusion and microdilution methods.Results:The antimicrobial activities of the crude extracts were increased with increasing the concentration. It is clear thatn-hexane extract was the most effective extract. Additionally, Gram positiveBacillus cereus (B. cereus) appear to be the most sensitive strain whilePseudomonas aeruginosa (P. aeruginosa) and the yeast strains (Candida albicans (C. albicans) andCryptococcus neoformans (C. neoformans)) appear to be resistance to the tested concentrations since no inhibition zone was observed. The inhibition of microbial growth at concentration as low as0.04 mg/mL indicated the potent antimicrobial activity ofL. littorea extracts.Conclusions:The obtained results are considered sufficient for further study to isolate the compounds responsible for the activity and suggesting the possibility of finding potent antibacterial agents fromL. littorea extracts.

  2. Antimicrobial activity of Tridax procumbens leaf

    Directory of Open Access Journals (Sweden)

    S.Santhosh Kumar

    2015-03-01

    Full Text Available Estimation of the antimicrobial property of Tridax procumbens’s leaf was carried out by the use of chloroform, petroleum ether, ethyl alcohol and hexaneas solvents. Leaf extract of Tridax procumbens obtained by soxhlet extractor, using the above mentioned solvents were examined against Escherichia coli, Bacillus subtilis, and Pseudomonas vulgaris. The antimicrobial activity of Tridax procumbens performed by using agarwell diffusion method showed a result showcasing an effective limit when as opposed to Pseudomonas vulgarisfor ethyl alcohol being used as solvent for extract. In conclusion Tridax procumbens leaf extract terminates most propitious source.

  3. In vitro antimicrobial activity of olive leaves.

    Science.gov (United States)

    Markin, D; Duek, L; Berdicevsky, I

    2003-04-01

    We investigated the antimicrobial effect of olive leaves against bacteria and fungi. The microorganisms tested were inoculated in various concentrations of olive leaf water extract. Olive leaf 0.6% (w/v) water extract killed almost all bacteria tested, within 3 h. Dermatophytes were inhibited by 1.25% (w/v) plant extract following a 3-day exposure whereas Candida albicans was killed following a 24 h incubation in the presence of 15% (w/v) plant extract. Olive leaf extract fractions, obtained by dialysis, that showed antimicrobial activity consisted of particles smaller than 1000 molecular rate cutoffs. Scanning electron microscopic observations of C. albicans, exposed to 40% (w/v) olive leaf extract, showed invaginated and amorphous cells. Escherichia coli cells, subjected to a similar treatment but exposed to only 0.6% (w/v) olive leaf extract showed complete destruction. These findings suggest an antimicrobial potential for olive leaves.

  4. The antimicrobial activity of liposomal lauric acids against Propionibacterium acnes.

    Science.gov (United States)

    Yang, Darren; Pornpattananangkul, Dissaya; Nakatsuji, Teruaki; Chan, Michael; Carson, Dennis; Huang, Chun-Ming; Zhang, Liangfang

    2009-10-01

    This study evaluated the antimicrobial activity of lauric acid (LA) and its liposomal derivatives against Propionibacterium acnes (P. acnes), the bacterium that promotes inflammatory acne. First, the antimicrobial study of three free fatty acids (lauric acid, palmitic acid and oleic acid) demonstrated that LA gives the strongest bactericidal activity against P. acnes. However, a setback of using LA as a potential treatment for inflammatory acne is its poor water solubility. Then the LA was incorporated into a liposome formulation to aid its delivery to P. acnes. It was demonstrated that the antimicrobial activity of LA was not only well maintained in its liposomal derivatives but also enhanced at low LA concentration. In addition, the antimicrobial activity of LA-loaded liposomes (LipoLA) mainly depended on the LA loading concentration per single liposomes. Further study found that the LipoLA could fuse with the membranes of P. acnes and release the carried LA directly into the bacterial membranes, thereby killing the bacteria effectively. Since LA is a natural compound that is the main acid in coconut oil and also resides in human breast milk and liposomes have been successfully and widely applied as a drug delivery vehicle in the clinic, the LipoLA developed in this work holds great potential of becoming an innate, safe and effective therapeutic medication for acne vulgaris and other P. acnes associated diseases.

  5. Thymus vulgaris essential oil: chemical composition and antimicrobial activity.

    Science.gov (United States)

    Borugă, O; Jianu, C; Mişcă, C; Goleţ, I; Gruia, A T; Horhat, F G

    2014-01-01

    The study was designed to determine the chemical composition and antimicrobial properties of the essential oil of Thymus vulgaris cultivated in Romania. The essential oil was isolated in a yield of 1.25% by steam distillation from the aerial part of the plant and subsequently analyzed by GC-MS. The major components were p-cymene (8.41%), γ-terpinene (30.90%) and thymol (47.59%). Its antimicrobial activity was evaluated on 7 common food-related bacteria and fungus by using the disk diffusion method. The results demonstrate that the Thymus vulgaris essential oil tested possesses strong antimicrobial properties, and may in the future represent a new source of natural antiseptics with applications in the pharmaceutical and food industry.

  6. Activity of Antimicrobial Silver Polystyrene Nanocomposites

    Directory of Open Access Journals (Sweden)

    M. Palomba

    2012-01-01

    Full Text Available A simple technique based on doping polymers with in situ generated silver nanoparticles (Ag/PS films has been developed. In particular, an antiseptic material has been prepared by dissolving silver 1,5-cyclooctadiene-hexafluoroacetylacetonate in amorphous polystyrene, and the obtained solid solution has been heated for ca. 10 s at a convenient temperature (180°C. Under such conditions the metal precursor decomposes producing silver atoms that diffuse into the polymer and clusterize. The antimicrobial characteristics of the resulting polystyrene-based material have been accurately evaluated toward Escherichia coli (E. coli comparing the cytotoxicity effect of 10 wt.% and 30 wt.% (drastic and mild annealing silver-doped polystyrene to the corresponding pure micrometric silver powder. Two different bacterial viability assays were performed in order to demonstrate the cytotoxic effect of Ag/PS films on cultured E. coli: (1 turbidimetric determination of optical density; (2 BacLight fluorescence-based test. Both methods have shown that silver-doped polystyrene (30 wt.% provides higher antibacterial activity than pure Ag powder, under similar concentration and incubation conditions.

  7. Antioxidant, Antimicrobial and Antiproliferative Activities of Five Lichen Species

    Directory of Open Access Journals (Sweden)

    Snežana Marković

    2011-08-01

    Full Text Available The antioxidative, antimicrobial and antiproliferative potentials of the methanol extracts of the lichen species Parmelia sulcata, Flavoparmelia caperata, Evernia prunastri, Hypogymnia physodes and Cladonia foliacea were evaluated. The total phenolic content of the tested extracts varied from 78.12 to 141.59 mg of gallic acid equivalent (GA/g of extract and the total flavonoid content from 20.14 to 44.43 mg of rutin equivalent (Ru/g of extract. The antioxidant capacities of the lichen extracts were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH radicals scavenging. Hypogymnia physodes with the highest phenolic content showed the strongest DPPH radical scavenging effect. Further, the antimicrobial potential of the lichen extracts was determined by a microdilution method on 29 microorganisms, including 15 strains of bacteria, 10 species of filamentous fungi and 4 yeast species. A high antimicrobial activity of all the tested extracts was observed with more potent inhibitory effects on the growth of Gram (+ bacteria. The highest antimicrobial activity among lichens was demonstrated by Hypogymnia physodes and Cladonia foliacea. Finally, the antiproliferative activity of the lichen extracts was explored on the colon cancer adenocarcinoma cell line HCT-116 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide viability assay and acridine orange/ethidium bromide staining. The methanol extracts of Hypogymnia physodes and Cladonia foliacea showed a better cytotoxic activity than the other extracts. All lichen species showed the ability to induce apoptosis of HCT-116 cells.

  8. Antioxidant, antimicrobial and antiproliferative activities of five lichen species.

    Science.gov (United States)

    Mitrović, Tatjana; Stamenković, Slaviša; Cvetković, Vladimir; Tošić, Svetlana; Stanković, Milan; Radojević, Ivana; Stefanović, Olgica; Comić, Ljiljana; Dačić, Dragana; Curčić, Milena; Marković, Snežana

    2011-01-01

    The antioxidative, antimicrobial and antiproliferative potentials of the methanol extracts of the lichen species Parmelia sulcata, Flavoparmelia caperata, Evernia prunastri, Hypogymnia physodes and Cladonia foliacea were evaluated. The total phenolic content of the tested extracts varied from 78.12 to 141.59 mg of gallic acid equivalent (GA)/g of extract and the total flavonoid content from 20.14 to 44.43 mg of rutin equivalent (Ru)/g of extract. The antioxidant capacities of the lichen extracts were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging. Hypogymnia physodes with the highest phenolic content showed the strongest DPPH radical scavenging effect. Further, the antimicrobial potential of the lichen extracts was determined by a microdilution method on 29 microorganisms, including 15 strains of bacteria, 10 species of filamentous fungi and 4 yeast species. A high antimicrobial activity of all the tested extracts was observed with more potent inhibitory effects on the growth of Gram (+) bacteria. The highest antimicrobial activity among lichens was demonstrated by Hypogymnia physodes and Cladonia foliacea. Finally, the antiproliferative activity of the lichen extracts was explored on the colon cancer adenocarcinoma cell line HCT-116 by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) viability assay and acridine orange/ethidium bromide staining. The methanol extracts of Hypogymnia physodes and Cladonia foliacea showed a better cytotoxic activity than the other extracts. All lichen species showed the ability to induce apoptosis of HCT-116 cells.

  9. Antimicrobial activity of coconut shell liquid smoke

    Science.gov (United States)

    Kailaku, SI; Syakir, M.; Mulyawanti, I.; Syah, ANA

    2017-06-01

    Coconut shell liquid smoke is produced from the pyrolysis and condensation of smoke from the burning process of coconut shell. It is known to have considerably high content of polyphenol. Beside acting as antioxidant, polyphenol is also a good antimicrobial. This research was conducted in order to study the antimicrobial activity of coconut shell liquid smoke. Coconut shell liquid smoke used in this study was produced from three different processing stages, which obtained three different grades of liquid smoke (grade 1, 2 and 3). Each sample of coconut shell liquid smoke was extracted using ethyl alcohol and petroleum ether. The extract was then analyzed for its antimicrobial activity against S. aereus, E. coli and C. albicans using well diffusion method. Total phenol and microbial microscopic structure of the liquid smoke were also examined. The results showed that there was influence of coconut shell liquid smoke on the inhibition of S. aureus, E. coli and C. albican growth. This fact was marked by the forming of clear area surrounding the well on the dish agar media. The highest percentage of inhibition showed by the extract of grade 3 coconut shell liquid smoke. This may be explained by the highest total phenol content in grade 3 liquid smoke. Microscopic examination showed that there was a breakage of microbial cell walls caused by the antimicrobial property of the liquid smoke. It was concluded that coconut shell liquid smoke was beneficial as antimicrobial agent, and while all grades of liquid smoke contains polyphenol, the content was influenced by the processing stage and thus influenced its level of microbial growth inhibition.

  10. The antimicrobial efficiency of silver activated sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Đolić, Maja B., E-mail: mirkovic.maja@gmail.com [Vinča Institute of Nuclear Sciences, University of Belgrade, P.O. Box 522, 11001 Belgrade (Serbia); Rajaković-Ognjanović, Vladana N. [Faculty of Civil Engineering, University of Belgrade, Bulevar Kralja Aleksandra 73, 11000 Belgrade (Serbia); Štrbac, Svetlana B. [ICTM-Institute of Electrochemistry, University of Belgrade, Njegoševa 12, 11001 Belgrade (Serbia); Rakočević, Zlatko Lj. [Vinča Institute of Nuclear Sciences, University of Belgrade, P.O. Box 522, 11001 Belgrade (Serbia); Veljović, Đorđe N.; Dimitrijević, Suzana I.; Rajaković, Ljubinka V. [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade (Serbia)

    2015-12-01

    Highlights: • Different sorbents were activated by Ag{sup +}-ions and modified sorbents were determined by sorption capacities, in range of values: 42.06–3.28 mg/g. • Granulated activated carbon (GAC), natural zeolit (Z) and titanium dioxide (T) activated by Ag{sup +}-ions were tested against E. coli, S. aureus and C. albicans. • The most successful bacteria removal was obtained using Ag/Z against S. aureus and E. coli, while the yeast cell reduction reached unsatisfactory effect for all three activated sorbents. • XRD, XPS and FE-SEM analysis showed that the chemical state of the silver activating agent affects the antimicrobial activity, as well as the structural properties of the material. • An overall microbial cell reduction, which is performed by separated antimicrobial tests on the Ag{sup +}-activated surface and Ag{sup +}-ions in aquatic solutions, is a consequence of both mechanisms. - Abstract: This study is focused on the surface modifications of the materials that are used for antimicrobial water treatment. Sorbents of different origin were activated by Ag{sup +}-ions. The selection of the most appropriate materials and the most effective activation agents was done according to the results of the sorption and desorption kinetic studies. Sorption capacities of selected sorbents: granulated activated carbon (GAC), zeolite (Z), and titanium dioxide (T), activated by Ag{sup +}-ions were following: 42.06, 13.51 and 17.53 mg/g, respectively. The antimicrobial activity of Ag/Z, Ag/GAC and Ag/T sorbents were tested against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. After 15 min of exposure period, the highest cell removal was obtained using Ag/Z against S. aureus and E. coli, 98.8 and 93.5%, respectively. Yeast cell inactivation was unsatisfactory for all three activated sorbents. The antimicrobial pathway of the activated sorbents has been examined by two separate tests – Ag{sup +}-ions desorbed from

  11. Antimicrobial activity of Syagrus coronata (Martius Beccari

    Directory of Open Access Journals (Sweden)

    Alice Ferreira da Silva Hughes

    2013-04-01

    Full Text Available This work aimed to evaluate the antimicrobial activity of aqueous and methanol extracts of leaves, inflorescences, nut-shell, liquid and solid endosperm nuts of Syagrus coronata against pathogenic bacteria and yeast. Screening was initially performed using the agar dilution method. The extracts regarded as bioactive underwent liquid-liquid partition for determination of their minimum inhibitory concentration and minimum bactericide concentration (MIC and MBC and those of their respective fractions against the microorganisms inhibited in preliminary tests. Antimicrobial activity was observed only in inflorescences. The corresponding aqueous extract was effective against B. cereus and the three strains of S. aureus, and the corresponding MIC and MCB values were lower than those of dichloromethane, ethyl acetate and butanol fractions of the same extract. The methanol extract was effective against B. cereus, and the corresponding MIC and MBC values were higher than those of ethyl acetate and butanol fractions of the same extract.

  12. Antimicrobial and cytotoxic activities of Abroma augusta Lnn. leaves extract

    Institute of Scientific and Technical Information of China (English)

    FK Saikot; Alam Khan; MF Hasan

    2012-01-01

    Objective: To evaluate the antimicrobial and cytotoxic activity of acetone extract of leaves ofAbroma augusta. Methods: Disc diffusion method was used to demonstrate antibacterial and antifungal activities. Cytotoxicity was determined against brine shrimp nauplii. In addition, minimum inhibitory concentration (MIC) was determined using serial dilution technique to determine antibacterial potency. Results: The extract showed significant antibacterial activities against three gram-positive (Bacillus subtilis, Bacillus megaterium and Staphylococcus aureus) and four gram-negative (Escherichia coli, Shigella dysenteriae, Shigella sonnei and Salmonella typhi) bacteria. The antifungal activity was found strong against five fungi (Aspergillus flavus, Aspergillus niger, Candida albicans, Rhizopus oryzae and Aspergillus fumigatus). In cytotoxicity determination, LC50 of the extract against brine shrimp nauplii was 7.06μg/ml. Conclusions: The Abroma leaves extract may be consider as a potent antimicrobial and cytotoxic agent for further advance research.

  13. Antimicrobial activity ofGymnema sylvestre (Asclepiadaceae)

    Institute of Scientific and Technical Information of China (English)

    Beverly C. David; G. Sudarsanam

    2013-01-01

    Objective:To evaluate antimicrobial activities of aqueous, methanol, chloroform and hexane extract of leaves plant ofGymnema sylvestre(G. sylvestre).Methods:The antimicrobial screening of the extracts ofG. sylvestre against most prevalent microbes likeStaphylococcus aureus(S. aureus),Bacillus cereus(B. cereus),Klebsiella pneumoniae(K. pneumoniae),Escherichia coli(E. coli),Candida albicans(C. albicans),Candida tropicalis(C. tropicalis),Candida krusei(C. krusei) andCandida kefyr(C. kefyr) by agar well diffusion method, minimum inhibitory concentration, minimum bactericidal concentration, minimum fungicidal concentration were carried out. Results:The aqueous and methanol leaf extract showed significant antibacterial and antifungal activities against the selected microorganisms when compared to the standard drugs respectively. Conclusions:The dried scale leaves ofG. sylvestre might represent a new antimicrobial source with stable, biologically active components that can establish a scientific base for the use in modern medicine.

  14. Antimicrobial Activity of Indigofera suffruticosa

    Directory of Open Access Journals (Sweden)

    Sônia Pereira Leite

    2006-01-01

    Full Text Available Various organic and aqueous extracts of leaves of Indigofera suffruticosa Mill (Fabaceae obtained by infusion and maceration were screened for their antibacterial and antifungal activities. The extracts were tested against 5 different species of human pathogenic bacteria and 17 fungal strains by the agar-solid diffusion method. Most of the extracts were devoid of antifungal and antibacterial activities, except the aqueous extract of leaves of I. suffruticosa obtained by infusion, which showed strong inhibitory activity against the Gram-positive bacteria Staphylococcus aureus with a minimal inhibitory concentration (MIC of 5000 µg ml−1. The MIC values to dermatophyte strains were 2500 µg ml−1 against Trichophyton rubrum (LM-09, LM-13 and Microsporum canis. This study suggests that aqueous extracts of leaves of I. suffruticosa obtained by infusion can be used in the treatment of skin diseases caused by dermatophytes.

  15. Biosynthesis and Antimicrobial Activity of Semiconductor Nanoparticles against Oral Pathogens

    OpenAIRE

    C. Malarkodi; Rajeshkumar, S.; K. Paulkumar; Vanaja, M.; Gnanajobitha, G.; Annadurai, G.

    2014-01-01

    Dental care is an essential phenomenon in human health. Oral pathogens can cause severe break which may show the way to serious issues in human disease like blood circulation and coronary disease. In the current study, we demonstrated the synthesis and antimicrobial activity of cadmium sulphide and zinc sulphide nanoparticles against oral pathogens. The process for the synthesis of cadmium sulphide (CdS) and zinc sulphide (ZnS) nanoparticles is fast, novel, and ecofriendly. Formation of cadmi...

  16. Essential Oils of Oregano: Biological Activity beyond Their Antimicrobial Properties

    Directory of Open Access Journals (Sweden)

    Nayely Leyva-López

    2017-06-01

    Full Text Available Essential oils of oregano are widely recognized for their antimicrobial activity, as well as their antiviral and antifungal properties. Nevertheless, recent investigations have demonstrated that these compounds are also potent antioxidant, anti-inflammatory, antidiabetic and cancer suppressor agents. These properties of oregano essential oils are of potential interest to the food, cosmetic and pharmaceutical industries. The aim of this manuscript is to review the latest evidence regarding essential oils of oregano and their beneficial effects on health.

  17. Antimicrobial Activity of Acanthephippium bicolor, Lindley

    Directory of Open Access Journals (Sweden)

    Kala, S.

    2010-01-01

    Full Text Available The Kolli hills, a part of Eastern Ghats of India is a treasure of medicinal plants. An attempt is made to gather information about the traditional use of herbs from the local healers. Acanthephippium bicolor Lindley is being used to treat urinary tract infection. Different parts (leaf, bulb and root are collected in two seasons (summer and winter and phytochemicals present in them are analyzed. Leaf is found to possess most of the phytochemicals. Hence leaf is selected as study material. Antimicrobial activity of the various solvent extracts (methanol, ethanol, chloroform, acetone, ethyl acetate, benzene and hexane is screened for both summer and winter samples. Of the 35 organisms studied, Staphylococcus aureus, Streptococcus foecalis, Bacillus cereus, Proteus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella dysenteriae, Escherichia coli, Microsporum audouinii, Microsporum fulvum, Candida albicans and Trichophyton rubrum are found to be sensitive to leaf extracts. The Gram-positive bacteria are found to be more sensitive than Gram-negative bacteria and fungi. The inhibition is found to be more in methanol extract. This proves that the bioactive compounds reside in methanolic extract. When the summer and winter samples are compared for their antimicrobial efficacy, there is no significant difference. This proves that there is no impact of season on antimicrobial activity of this plant. This research proves that Acanthephippium bicolor Lindley would be the best herbal medicine for Urinary Tract Infection and leaves can be used as herbal and scientific medicine throughout the year as there is no seasonal impact.

  18. Antimicrobial activity of bone cements embedded with organic nanoparticles

    Science.gov (United States)

    Perni, Stefano; Thenault, Victorien; Abdo, Pauline; Margulis, Katrin; Magdassi, Shlomo; Prokopovich, Polina

    2015-01-01

    Infections after orthopedic surgery are a very unwelcome outcome; despite the widespread use of antibiotics, their incidence can be as high as 10%. This risk is likely to increase as antibiotics are gradually losing efficacy as a result of bacterial resistance; therefore, novel antimicrobial approaches are required. Parabens are a class of compounds whose antimicrobial activity is employed in many cosmetic and pharmaceutical products. We developed propylparaben nanoparticles that are hydrophilic, thus expanding the applicability of parabens to aqueous systems. In this paper we assess the possibility of employing paraben nanoparticles as antimicrobial compound in bone cements. The nanoparticles were embedded in various types of bone cement (poly(methyl methacrylate) [PMMA], hydroxyapatite, and brushite) and the antimicrobial activity was determined against common causes of postorthopedic surgery infections such as: Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, and Acinetobacter baumannii. Nanoparticles at concentrations as low as 1% w/w in brushite bone cement were capable of preventing pathogens growth, 5% w/w was needed for hydroxyapatite bone cement, while 7% w/w was required for PMMA bone cement. No detrimental effect was determined by the addition of paraben nanoparticles on bone cement compression strength and cytocompatibility. Our results demonstrate that paraben nanoparticles can be encapsulated in bone cement, providing concentration-dependent antimicrobial activity; furthermore, lower concentrations are needed in calcium phosphate (brushite and hydroxyapatite) than in acrylic (PMMA) bone cements. These nanoparticles are effective against a wide spectrum of bacteria, including those already resistant to the antibiotics routinely employed in orthopedic applications, such as gentamicin. PMID:26487803

  19. New alkoxycarbonylalkyloxychalcones and their alpha, beta-dibromo derivatives of potential antimicrobial activity.

    Science.gov (United States)

    Szajda, M; Kedzia, B

    1989-03-01

    New ortho, meta- and para-substituted alkoxycarbonylalkyloxychalcones and their alpha, beta-dibromo derivatives have been synthesized. It can be demonstrated that some of these compounds show antimicrobial activity.

  20. Antimicrobial Activity of UV-Induced Phenylamides from Rice Leaves

    Directory of Open Access Journals (Sweden)

    Hye Lin Park

    2014-11-01

    Full Text Available Rice produces a wide array of phytoalexins in response to pathogen attacks and UV-irradiation. Except for the flavonoid sakuranetin, most phytoalexins identified in rice are diterpenoid compounds. Analysis of phenolic-enriched fractions from UV-treated rice leaves showed that several phenolic compounds in addition to sakuranetin accumulated remarkably in rice leaves. We isolated two compounds from UV-treated rice leaves using silica gel column chromatography and preparative HPLC. The isolated phenolic compounds were identified as phenylamide compounds: N-trans-cinnamoyltryptamine and N-p-coumaroylserotonin. Expression analysis of biosynthetic genes demonstrated that genes for arylamine biosynthesis were upregulated by UV irradiation. This result suggested that phenylamide biosynthetic pathways are activated in rice leaves by UV treatment. To unravel the role of UV-induced phenylamides as phytoalexins, we examined their antimicrobial activity against rice fungal and bacterial pathogens. N-trans-Cinnamoyltryptamine inhibited the growth of rice brown spot fungus (Bipolaris oryzae. In addition to the known antifungal activity to the blast fungus, sakuranetin had antimicrobial activity toward B. oryzae and Rhizoctonia solani (rice sheath blight fungus. UV-induced phenylamides and sakuranetin also had antimicrobial activity against rice bacterial pathogens for grain rot (Burkholderia glumae, blight (Xanthomonas oryzae pv. oryzae and leaf streak (X. oryzae pv. oryzicola diseases. These findings suggested that the UV-induced phenylamides in rice are phytoalexins against a diverse array of pathogens.

  1. Antimicrobial activity of ProRoot MTA in contact with blood

    Science.gov (United States)

    Farrugia, C.; Baca, P.; Camilleri, J.; Arias Moliz, M. T.

    2017-01-01

    Dental materials based on Portland cement, which is used in the construction industry have gained popularity for clinical use due to their hydraulic properties, the interaction with tooth tissue and their antimicrobial properties. The antimicrobial properties are optimal in vitro. However in clinical use contact with blood may affect the antimicrobial properties. This study aims to assess whether antimicrobial properties of the Portland cement-based dental cements such as mineral trioxide aggregate (MTA) are also affected by contact with blood present in clinical situations. ProRoot MTA, a Portland cement-based dental cement was characterized following contact with water, or heparinized blood after 1 day and 7 days aging. The antimicrobial activity under the mentioned conditions was assessed using 3 antimicrobial tests: agar diffusion test, direct contact test and intratubular infection test. MTA in contact with blood was severely discoloured, exhibited an additional phosphorus peak in elemental analysis, no calcium hydroxide peaks and no areas of bacterial inhibition growth in the agar diffusion test were demonstrated. ProRoot MTA showed limited antimicrobial activity, in both the direct contact test and intratubular infection test. When aged in water ProRoot MTA showed higher antimicrobial activity than when aged in blood. Antimicrobial activity reduced significantly after 7 days. Further assessment is required to investigate behaviour in clinical situations. PMID:28128328

  2. Antimicrobial activity of ProRoot MTA in contact with blood.

    Science.gov (United States)

    Farrugia, C; Baca, P; Camilleri, J; Arias Moliz, M T

    2017-01-27

    Dental materials based on Portland cement, which is used in the construction industry have gained popularity for clinical use due to their hydraulic properties, the interaction with tooth tissue and their antimicrobial properties. The antimicrobial properties are optimal in vitro. However in clinical use contact with blood may affect the antimicrobial properties. This study aims to assess whether antimicrobial properties of the Portland cement-based dental cements such as mineral trioxide aggregate (MTA) are also affected by contact with blood present in clinical situations. ProRoot MTA, a Portland cement-based dental cement was characterized following contact with water, or heparinized blood after 1 day and 7 days aging. The antimicrobial activity under the mentioned conditions was assessed using 3 antimicrobial tests: agar diffusion test, direct contact test and intratubular infection test. MTA in contact with blood was severely discoloured, exhibited an additional phosphorus peak in elemental analysis, no calcium hydroxide peaks and no areas of bacterial inhibition growth in the agar diffusion test were demonstrated. ProRoot MTA showed limited antimicrobial activity, in both the direct contact test and intratubular infection test. When aged in water ProRoot MTA showed higher antimicrobial activity than when aged in blood. Antimicrobial activity reduced significantly after 7 days. Further assessment is required to investigate behaviour in clinical situations.

  3. ANTIMICROBIAL ACTIVITY OF TUSSILAGO FARFARA L.

    Directory of Open Access Journals (Sweden)

    Miroslava Kačániová

    2013-02-01

    Full Text Available In this study, ethanolic extracts of Tussilago farfara L. which had been described in herbal books, were screened for their antimicrobial activity. The following strains of bacteria for antimicrobial activity were used Escherichia coli CCM 3988, Serratia rubidea CCM 4684, Staphylococcus epidermis CC 4418, Lactobacillus rhamnosus CCM 1828, Pseudomonas aeroginosa CCM 1960 and Enterococcus raffinosus CCM 4216. The yeast strain used in this study was Saccharomyces cerevisiae CCM 8191 using disc diffusion method and microbroth dilution technique. The highest antibacterial activity of Tussilago farfara L. ethanolic extract was measured in Grampositive bacteria Lactobacillus rhamnosus (6.67±1.53 mm and lower in yeast Saccharomyces cerevisiae (1.67±0.58 mm with disc diffusion method used. The ethanolic extract present an important activity against Saccharomyces cerevisiae (MIC50=24 µg.ml-1; MIC90=25.69 µg.ml-1 and Serratia rubidaea (MIC=48.01 µg.ml-1; MIC90=51.26 µg.ml-1 with microbroth dilution technique used.

  4. Antimicrobial activity ofTerminalia bellerica

    OpenAIRE

    Elizabeth, K. M.

    2005-01-01

    The antimicrobial activity of crude and methanol extract ofTerminalia bellerica dry fruit was tested by disc diffusion method, against 9 human microbial pathogens. Crude aqueous extract of dry fruit at 4 mg concentration showed zone of inhibition ranging from 15.5–28.0 mm.S. aureus was found to be highly susceptible forming highest zone of inhibition, suggesting thatT. bellerica was strongly inhibitory towards this organism. These pathogens were highly sensitive to the methanol extract formin...

  5. Screening of Australian plants for antimicrobial activity against Campylobacter jejuni.

    Science.gov (United States)

    Kurekci, Cemil; Bishop-Hurley, Sharon L; Vercoe, Philip E; Durmic, Zoey; Al Jassim, Rafat A M; McSweeney, Christopher S

    2012-02-01

    Campylobacter jejuni is the most common cause of acute enteritis in humans, with symptoms such as diarrhoea, fever and abdominal cramps. In this study, 115 extracts from 109 Australian plant species were investigated for their antimicrobial activities against two C. jejuni strains using an in vitro broth microdilution assay. Among the plants tested, 107 (93%) extracts showed activity at a concentration between 32 and 1024 µg/mL against at least one C. jejuni strain. Seventeen plant extracts were selected for further testing against another six C. jejuni strains, as well as Campylobacter coli, Escherichia coli, Salmonella typhimurium, Bacillus cereus, Proteus mirabilis and Enterococcus faecalis. The extract from Eucalyptus occidentalis demonstrated the highest antimicrobial activity, with an inhibitory concentration of 32 µg/mL against C. jejuni and B. cereus. This study has shown that extracts of selected Australian plants possess antimicrobial activity against C. jejuni and thus may have application in the control of this organism in live poultry and retail poultry products.

  6. Antimicrobial resistance and the activities of the Codex Alimentarius Commission.

    Science.gov (United States)

    Bruno, A V; Mackay, Carolissen

    2012-04-01

    The Codex Alimentarius Commission has been working on the subject of antimicrobial resistance, mainly through the activities of the Committee on Residues of Veterinary Drugs in Foods and the ad hoc Intergovernmental Task Force on Antimicrobial Resistance. Principal texts developed by Codex include the 'Code of Practice to Minimize and Contain Antimicrobial Resistance (CAC/RCP 61-2005) and 'Guidelines for Risk Analysis of Foodborne Antimicrobial Resistance' (CAC/GL 77-2011). The successful containment of antimicrobial resistance requires the collaboration of a wide range of stakeholders, working together to protect consumer health by ensuring the safety of food products of animal origin.

  7. Quaternized Chitosan as an Antimicrobial Agent: Antimicrobial Activity, Mechanism of Action and Biomedical Applications in Orthopedics

    Directory of Open Access Journals (Sweden)

    Ziwei Liu

    2013-01-01

    Full Text Available Chitosan (CS is a linear polysaccharide with good biodegradability, biocompatibility and antimicrobial activity, which makes it potentially useful for biomedical applications, including an antimicrobial agent either alone or blended with other polymers. However, the poor solubility of CS in most solvents at neutral or high pH substantially limits its use. Quaternary ammonium CS, which was prepared by introducing a quaternary ammonium group on a dissociative hydroxyl group or amino group of the CS, exhibited improved water solubility and stronger antibacterial activity relative to CS over an entire range of pH values; thus, this quaternary modification increases the potential biomedical applications of CS in the field of anti-infection. This review discusses the current findings on the antimicrobial properties of quaternized CS synthesized using different methods and the mechanisms of its antimicrobial actions. The potential antimicrobial applications in the orthopedic field and perspectives regarding future studies in this field are also considered.

  8. Impact of interspecific interactions on antimicrobial activity among soil bacteria.

    Science.gov (United States)

    Tyc, Olaf; van den Berg, Marlies; Gerards, Saskia; van Veen, Johannes A; Raaijmakers, Jos M; de Boer, Wietse; Garbeva, Paolina

    2014-01-01

    Certain bacterial species produce antimicrobial compounds only in the presence of a competing species. However, little is known on the frequency of interaction-mediated induction of antibiotic compound production in natural communities of soil bacteria. Here we developed a high-throughput method to screen for the production of antimicrobial activity by monocultures and pair-wise combinations of 146 phylogenetically different bacteria isolated from similar soil habitats. Growth responses of two human pathogenic model organisms, Escherichia coli WA321 and Staphylococcus aureus 533R4, were used to monitor antimicrobial activity. From all isolates, 33% showed antimicrobial activity only in monoculture and 42% showed activity only when tested in interactions. More bacterial isolates were active against S. aureus than against E. coli. The frequency of interaction-mediated induction of antimicrobial activity was 6% (154 interactions out of 2798) indicating that only a limited set of species combinations showed such activity. The screening revealed also interaction-mediated suppression of antimicrobial activity for 22% of all combinations tested. Whereas all patterns of antimicrobial activity (non-induced production, induced production and suppression) were seen for various bacterial classes, interaction-mediated induction of antimicrobial activity was more frequent for combinations of Flavobacteria and alpha- Proteobacteria. The results of our study give a first indication on the frequency of interference competitive interactions in natural soil bacterial communities which may forms a basis for selection of bacterial groups that are promising for the discovery of novel, cryptic antibiotics.

  9. Antimicrobial activity of bone cements embedded with organic nanoparticles

    Directory of Open Access Journals (Sweden)

    Perni S

    2015-10-01

    Full Text Available Stefano Perni,1,2 Victorien Thenault,1 Pauline Abdo,1 Katrin Margulis,3 Shlomo Magdassi,3 Polina Prokopovich1,2 1School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff, UK; 2Center for Biomedical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA; 3Casali Institute, Institute of Chemistry, The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem, IsraelAbstract: Infections after orthopedic surgery are a very unwelcome outcome; despite the widespread use of antibiotics, their incidence can be as high as 10%. This risk is likely to increase as antibiotics are gradually losing efficacy as a result of bacterial resistance; therefore, novel antimicrobial approaches are required. Parabens are a class of compounds whose antimicrobial activity is employed in many cosmetic and pharmaceutical products. We developed propylparaben nanoparticles that are hydrophilic, thus expanding the applicability of parabens to aqueous systems. In this paper we assess the possibility of employing paraben nanoparticles as antimicrobial compound in bone cements. The nanoparticles were embedded in various types of bone cement (poly(methyl methacrylate [PMMA], hydroxyapatite, and brushite and the antimicrobial activity was determined against common causes of postorthopedic surgery infections such as: Staphylococcus aureus, methicillin-resistant S. aureus, Staphylococcus epidermidis, and Acinetobacter baumannii. Nanoparticles at concentrations as low as 1% w/w in brushite bone cement were capable of preventing pathogens growth, 5% w/w was needed for hydroxyapatite bone cement, while 7% w/w was required for PMMA bone cement. No ­detrimental effect was determined by the addition of paraben nanoparticles on bone cement compression strength and cytocompatibility. Our results demonstrate that paraben nanoparticles can be encapsulated in bone cement, providing concentration-dependent antimicrobial

  10. Anti-microbial activity of Leucas clarkei

    Directory of Open Access Journals (Sweden)

    Surya Narayan Das

    2012-06-01

    Full Text Available The antimicrobial potency of the whole plant of Leucas clarkei have been studied using the soxhlet extracts of petroleum ether, benzene, chloroform and ethanol extract against Gram-positive bacteria (two strains, Gram-negative bacteria (two strains and two fungi strains by disc diffusion method. Micro-dilution methods, for the determination of minimal inhibition concentration (MIC and the minimal bactericidal and fungicidal concentration (MBC, MFC. The ethanol extract at a concentration of 30 to 60 µg/disc and chloroform extract at a concentration 60 µg/disc showed significant activity against all the bacteria and fungus. All the extracts of L. clarkei have got moderate action but chloroform and ethanol extracts have got significant activity against Candida krusei, Candida albicans, Escherichia coli, Salmonella typhi, Staphylococcus aureus, and Bacillus subtilis. This may be due to phytochemicals such as phytosterols, alkaloid, tannins, phenolic compounds and flavonoids present in the extracts.

  11. Antimicrobial activity of human salivary mucin-derived peptides

    NARCIS (Netherlands)

    Wei, G.

    2008-01-01

    We investigated: a) relationships between molecular properties and antimicrobial functions of MUC7 peptides, b) effects of host physiological factors on the antimicrobial activity of MUC7 peptides, c) enhancement of antifungal activity by combination of MUC7 peptides with EDTA or other agents, d) an

  12. Antimicrobial activity of camwood (Baphia nitida) dyes on common ...

    African Journals Online (AJOL)

    enoh

    2012-03-29

    Mar 29, 2012 ... Antimicrobial activity of four aqueous extracts of camwood dyes obtained from different locations in ... These results show that camwood dye possessed significant antimicrobial activity ... In Nigeria, the local use of natural products as source ... Bacterial inoculum was prepared by inoculating a loopful of the.

  13. Biologically Active and Antimicrobial Peptides from Plants

    Directory of Open Access Journals (Sweden)

    Carlos E. Salas

    2015-01-01

    Full Text Available Bioactive peptides are part of an innate response elicited by most living forms. In plants, they are produced ubiquitously in roots, seeds, flowers, stems, and leaves, highlighting their physiological importance. While most of the bioactive peptides produced in plants possess microbicide properties, there is evidence that they are also involved in cellular signaling. Structurally, there is an overall similarity when comparing them with those derived from animal or insect sources. The biological action of bioactive peptides initiates with the binding to the target membrane followed in most cases by membrane permeabilization and rupture. Here we present an overview of what is currently known about bioactive peptides from plants, focusing on their antimicrobial activity and their role in the plant signaling network and offering perspectives on their potential application.

  14. Poly(anhydride-esters) comprised exclusively of naturally occurring antimicrobials and EDTA: antioxidant and antibacterial activities.

    Science.gov (United States)

    Carbone-Howell, Ashley L; Stebbins, Nicholas D; Uhrich, Kathryn E

    2014-05-12

    Carvacrol, thymol, and eugenol are naturally occurring phenolic compounds known to possess antimicrobial activity against a range of bacteria, as well as antioxidant activity. Biodegradable poly(anhydride-esters) composed of an ethylenediaminetetraacetic acid (EDTA) backbone and antimicrobial pendant groups (i.e., carvacrol, thymol, or eugenol) were synthesized via solution polymerization. The resulting polymers were characterized to confirm their chemical composition and understand their thermal properties and molecular weight. In vitro release studies demonstrated that polymer hydrolytic degradation was complete after 16 days, resulting in the release of free antimicrobials and EDTA. Antioxidant and antibacterial assays determined that polymer release media exhibited bioactivity similar to that of free compound, demonstrating that polymer incorporation and subsequent release had no effect on activity. These polymers completely degrade into components that are biologically relevant and have the capability to promote preservation of consumer products in the food and personal care industries via antimicrobial and antioxidant pathways.

  15. Evaluation of Antimicrobial Activity of Root Extracts of Abitulon indicum

    Directory of Open Access Journals (Sweden)

    Krishna Rao MORTHA

    2015-06-01

    Full Text Available Antimicrobial activity of Abitulon indicum roots was studied against seven pathogenic bacteria and three fungal strains by agar well diffusion method. Antimicrobial activity was recorded for hexane, chloroform, methanol, ethanol and aqueous extracts. Alcohol (ethanol and methanol extracts exhibited the highest degree of antimicrobial activity compared to aqueous, chloroform and hexane extracts. Pseudomonas aeruginosa was turned out to be the most susceptible bacterium to the crude root chemical constituents, using the standard Tetracycline and Clotrimazole. Minimum inhibition concentration values of hexane, chloroform, methanol, ethanol and aqueous extracts were determined by the agar dilution method and ranged between 62.5 and 1,000 µg. The study suggested that the root extracts possess bioactive compounds with antimicrobial activity against the tested bacteria and fungi, revealing a significant scope to develop a novel broad spectrum of antimicrobial drug formulation from Abitulon indicum.

  16. Antimicrobial activity of herbs against Yersinia enterocolitica and mixed microflora

    Directory of Open Access Journals (Sweden)

    Shilpa SHARMA

    2016-12-01

    Full Text Available The present study aimed at developing herbal medicine against food borne pathogens, therefore the antimicrobial activity of four herbs viz. Arjuna (bark, Ashwagandha (roots, Puthkanda (leaves and Shalampanja (roots was checked. Aqueous, ethanolic and petroleum ether extracts of each herb were extracted and their antimicrobial activity against mixed microflora and against Yersinia enterocolitica was determined. Tetracycline and gentamicin were used as reference antibiotics. Arjuna extracts showed the highest antimicrobial potential against mixed population and Yersinia enterocolitica in comparison to Ashwagandha, Puthkanda and Shalampanja extracts. The antimicrobial activity of Arjuna aqueous extract was lower compared to gentamicin, but comparable to tetracycline. The minimum inhibitory concentration and minimum bactericidal concentration of aqueous extract of Arjuna showed the lowest values indicating that it is more effective in lower concentration of use. The antimicrobial activity of herbs showed the following trend Arjuna > Puthkanda > Shalampanja > Ashwagandha.

  17. Cytotoxicity and Antimicrobial Activity of Oral Rinses In Vitro

    National Research Council Canada - National Science Library

    Heinz-Dieter Müller; Sigrun Eick; Andreas Moritz; Adrian Lussi; Reinhard Gruber

    2017-01-01

    .... Antimicrobial activity was screened against five bacterial strains using disc diffusion. Cytotoxicity was determined by mitochondrial reductase activity with primary gingival fibroblasts, L929 cells, and HSC-2 epithelial cells...

  18. Development of elastin-like recombinamer films with antimicrobial activity

    DEFF Research Database (Denmark)

    Costa, André; Machado, Raul; Ribeiro, Artur

    2015-01-01

    In the present work we explored the ABP-CM4 peptide properties from Bombyx mori for the creation of biopolymers with broad antimicrobial activity. An antimicrobial recombinant protein-based polymer (rPBP) was designed by cloning the DNA sequence coding for ABP-CM4 in frame with the N-terminus of ...

  19. Antimicrobial activity of ultrasound-assisted solvent-extracted spices.

    Science.gov (United States)

    Thongson, C; Davidson, P M; Mahakarnchanakul, W; Weiss, J

    2004-01-01

    The objective of this research was to determine the antimicrobial activity of conventional and high-intensity ultrasound-assisted (HI-US) solvent-extracted Thai spices, including ginger (Zingiber officinale Rose), fingerroot (Bosenbergia pandurata Holtt) and turmeric (Curouma longa Linn). Extracts were obtained using hexane, isopropanol and a 7 : 3 isopropanol : hexane mixture as solvents with and without HI-US. The antimicrobial activity of the extracts was assayed against four strains each of Listeria monocytogenes and Salmonella Typhimurium DT 104 using an agar dilution assay. Application of HI-US did not alter antibacterial activity against S. Typhimurium, but antilisterial activity of some HI-US spice extracts decreased. Solvent type affected antimicrobial efficacy of extracts with hexane producing the least antimicrobial activity. Fingerroot extracted with isopropanol-hexane and without HI-US had the best antilisterial effect while HI-US-isopropanol fingerroot extract had the greatest antimicrobial efficacy against S. Typhimurium. Application of HI-US reduced time of extraction to 5 min, compared with the 24 h required for conventional extraction and maintained antimicrobial activity against Salmonella but slightly reduced activity against Listeria. HI-US in combination with proper solvent selection may offer a new tool to optimize extraction of spice essential oil for use as antimicrobial agents, and reduce processing time and costs.

  20. Antimicrobial Activity of Xanthohumol and Its Selected Structural Analogues.

    Science.gov (United States)

    Stompor, Monika; Żarowska, Barbara

    2016-05-11

    The objective of this study was to evaluate the antimicrobial activity of structural analogues of xanthohumol 1, a flavonoid compound found in hops (Humulus lupulus). The agar-diffusion method using filter paper disks was applied. Biological tests performed for selected strains of Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, fungi (Alternaria sp.), and yeasts (Rhodotorula rubra, Candida albicans) revealed that compounds with at least one hydroxyl group-all of them have it at the C-4 position-demonstrated good activity. Our research showed that the strain S. aureus was more sensitive to chalcones than to the isomers in which the heterocyclic ring C is closed (flavanones). The strain R. rubra was moderately sensitive to only one compound: 4-hydroxy-4'-methoxychalcone 8. Loss of the hydroxyl group in the B-ring of 4'-methoxychalcones or its replacement by a halogen atom (-Cl, -Br), nitro group (-NO₂), ethoxy group (-OCH₂CH₃), or aliphatic substituent (-CH₃, -CH₂CH₃) resulted in the loss of antimicrobial activity towards both R. rubra yeast and S. aureus bacteria. Xanthohumol 1, naringenin 5, and chalconaringenin 7 inhibited growth of S. aureus, whereas 4-hydroxy-4'-methoxychalcone 8 was active towards two strains: S. aureus and R. rubra.

  1. Prediction of antibacterial activity from physicochemical properties of antimicrobial peptides.

    Directory of Open Access Journals (Sweden)

    Manuel N Melo

    Full Text Available Consensus is gathering that antimicrobial peptides that exert their antibacterial action at the membrane level must reach a local concentration threshold to become active. Studies of peptide interaction with model membranes do identify such disruptive thresholds but demonstrations of the possible correlation of these with the in vivo onset of activity have only recently been proposed. In addition, such thresholds observed in model membranes occur at local peptide concentrations close to full membrane coverage. In this work we fully develop an interaction model of antimicrobial peptides with biological membranes; by exploring the consequences of the underlying partition formalism we arrive at a relationship that provides antibacterial activity prediction from two biophysical parameters: the affinity of the peptide to the membrane and the critical bound peptide to lipid ratio. A straightforward and robust method to implement this relationship, with potential application to high-throughput screening approaches, is presented and tested. In addition, disruptive thresholds in model membranes and the onset of antibacterial peptide activity are shown to occur over the same range of locally bound peptide concentrations (10 to 100 mM, which conciliates the two types of observations.

  2. Antimicrobial Activity of Xanthohumol and Its Selected Structural Analogues

    Directory of Open Access Journals (Sweden)

    Monika Stompor

    2016-05-01

    Full Text Available The objective of this study was to evaluate the antimicrobial activity of structural analogues of xanthohumol 1, a flavonoid compound found in hops (Humulus lupulus. The agar-diffusion method using filter paper disks was applied. Biological tests performed for selected strains of Gram-positive (Staphylococcus aureus and Gram-negative (Escherichia coli bacteria, fungi (Alternaria sp., and yeasts (Rhodotorula rubra, Candida albicans revealed that compounds with at least one hydroxyl group—all of them have it at the C-4 position—demonstrated good activity. Our research showed that the strain S. aureus was more sensitive to chalcones than to the isomers in which the heterocyclic ring C is closed (flavanones. The strain R. rubra was moderately sensitive to only one compound: 4-hydroxy-4’-methoxychalcone 8. Loss of the hydroxyl group in the B-ring of 4’-methoxychalcones or its replacement by a halogen atom (−Cl, −Br, nitro group (−NO2, ethoxy group (−OCH2CH3, or aliphatic substituent (−CH3, −CH2CH3 resulted in the loss of antimicrobial activity towards both R. rubra yeast and S. aureus bacteria. Xanthohumol 1, naringenin 5, and chalconaringenin 7 inhibited growth of S. aureus, whereas 4-hydroxy-4′-methoxychalcone 8 was active towards two strains: S. aureus and R. rubra.

  3. Fatty acid conjugation enhances the activities of antimicrobial peptides.

    Science.gov (United States)

    Li, Zhining; Yuan, Penghui; Xing, Meng; He, Zhumei; Dong, Chuanfu; Cao, Yongchang; Liu, Qiuyun

    2013-04-01

    Antimicrobial peptides are small molecules that play a crucial role in innate immunity in multi-cellular organisms, and usually expressed and secreted constantly at basal levels to prevent infection, but local production can be augmented upon an infection. The clock is ticking as rising antibiotic abuse has led to the emergence of many drug resistance bacteria. Due to their broad spectrum antibiotic and antifungal activities as well as anti-viral and anti-tumor activities, efforts are being made to develop antimicrobial peptides into future microbial agents. This article describes some of the recent patents on antimicrobial peptides with fatty acid conjugation. Potency and selectivity of antimicrobial peptide can be modulated with fatty acid tails of variable length. Interaction between membranes and antimicrobial peptides was affected by fatty acid conjugation. At concentrations above the critical miscelle concentration (CMC), propensity of solution selfassembly hampered binding of the peptide to cell membranes. Overall, fatty acid conjugation has enhanced the activities of antimicrobial peptides, and occasionally it rendered inactive antimicrobial peptides to be bioactive. Antimicrobial peptides can not only be used as medicine but also as food additives.

  4. [Antimicrobial activity of the epicarp of the fruits of Paulownia fortunei and Paulownia tomentosa].

    Science.gov (United States)

    Cercós, A P

    1982-01-01

    One antimicrobial substance was obtained from the epicarp of the fruits of Paulownia fortunei and Paulownia tomentosa. Other parts of the fruits and leaves had no detectable antimicrobial activity. The substance was active in vitro for Staphylococcus aureus and Bacillus subtilis while it had lower activity for Saccharomyces carlsbergensis and the lowest was for Escherichia coli. The active material was extracted with organic solvents (ether, ethanol and acetone). The activity "in vitro" was demonstrated by the method of dilution in nutrient agar media. The active substance looked as a resin and was insoluble in water at neutral or acid pH. It was very soluble in strong alkaline pH solution.

  5. Hydrocarbon-stapled lipopeptides exhibit selective antimicrobial activity.

    Science.gov (United States)

    Jenner, Zachary B; Crittenden, Christopher M; Gonzalez, Martín; Brodbelt, Jennifer S; Bruns, Kerry A

    2017-01-10

    Antimicrobial peptides (AMPs) occur widely in nature and have been studied for their therapeutic potential. AMPs are of interest due to the large number of possible chemical structural combinations using natural and unnatural amino acids, with varying effects on their biological activities. Using physicochemical properties from known naturally occurring amphipathic cationic AMPs, several hydrocarbon-stapled lipopeptides (HSLPs) were designed, synthesized, and tested for antimicrobial properties. Peptides were chemically modified by N-terminal acylation, C-terminal amidation, and some were hydrocarbon stapled by intramolecular olefin metathesis. The effects of peptide length, amphipathic character, and stapling on antimicrobial activity were tested against Escherichia coli, three species of Gram-positive bacteria (Staphylococcus aureus, Bacillus megaterium, and Enterococcus faecalis), and two strains of Candida albicans. Peptides were shown to disrupt liposomes of different phospholipid composition, as measured by leakage of a fluorescent compound from vesicles. Peptides with (S)-2-(4'-pentenyl)-alanine substituted for L-alanine in a reference peptide showed a marked increase in antimicrobial activity, hemolysis, and membrane disruption. Stapled peptides exhibited slightly higher antimicrobial potency; those with greatest hydrophobic character showed the greatest hemolysis and liposome leakage, but lower antimicrobial activity. The results support a model of HSLPs as membrane-disruptive AMPs with potent antimicrobial activity and relatively low hemolytic potential at biologically active peptide concentrations. This article is protected by copyright. All rights reserved.

  6. Antimicrobial activity of peppermint essential oil (Mentha piperita L.

    Directory of Open Access Journals (Sweden)

    Shapoval O.G.

    2011-12-01

    Full Text Available Рurposе. To study antimicrobial activity of fume of the essential oil of peppermint against gram-positive and gram-negative bacteria. Materials and methods: The screening study of antimicrobial activity of solutions of essential oil by disk-diffusion method and activity of essential oil fume of own preparation and pharmaceutical form of oil according to standard strains of Staphylococcus aureus, Pseudomonas aeruginosa, Esсherichia coli and 12 clinical strains of staphylococci (6 methicillin-resistant and 6 methicillin-sensitive has been carried out. Results: Essential oil of own preparation and pharmaceutical form showed equal antimicrobial activity against strains of staphylococci. Essential oil of own preparation has been determined to reveal higher activity against gram-negative strains. Conclusion: Received data have proved the presence of antimicrobial activity against all strains of microorganisms and mostly against staphy-lococci

  7. ANTIMICROBIAL ACTIVITIES OF 1,3,4-OXADIAZOLE : A REVIEW

    Directory of Open Access Journals (Sweden)

    Bachwani Mukesh

    2011-06-01

    Full Text Available 1, 3, 4-Oxadiazole is a highly privileged structure the derivatives of which exhibit a wide range of biological activities including antibacterial, antitubercular, vasodialatory, antifungal, cytotoxic, anti-inflammatory and analgesic, hypolipidemic, anticancer and ulcerogenic activities. Resistance to number of antimicrobial agents among a variety of clinically significant species of bacteria is becoming increasingly important global problem. The search for new antimicrobial agents will consequently always remain as an important and challenging task for medicinal chemists. This Review has basic information about 1,3,4-oxadiazole and its antimicrobial activity work for further development in this field.

  8. Radical scavenging, antioxidant and antimicrobial activities of halophytic species

    OpenAIRE

    Meot-Duros, Laetitia; Le Floch, Gaëtan; Magné, Christian

    2008-01-01

    International audience; For the first time, both antioxidant and antimicrobial activities are simultaneously reported in halophytic plants, particularly on polar fractions. Chloroformic and methanolic extracts of the halophytes Eryngium maritimum L., Crithmum maritimum L. and Cakile maritima Scop. were tested for their antimicrobial activities against 12 bacterial and yeast strains. In addition, radical scavenging and antioxidant activities were assessed, as well as total phenol contents. Onl...

  9. Self-assembly of cationic multidomain peptide hydrogels: supramolecular nanostructure and rheological properties dictate antimicrobial activity.

    Science.gov (United States)

    Jiang, Linhai; Xu, Dawei; Sellati, Timothy J; Dong, He

    2015-12-01

    Hydrogels are an important class of biomaterials that have been widely utilized for a variety of biomedical/medical applications. The biological performance of hydrogels, particularly those used as wound dressing could be greatly advanced if imbued with inherent antimicrobial activity capable of staving off colonization of the wound site by opportunistic bacterial pathogens. Possessing such antimicrobial properties would also protect the hydrogel itself from being adversely affected by microbial attachment to its surface. We have previously demonstrated the broad-spectrum antimicrobial activity of supramolecular assemblies of cationic multi-domain peptides (MDPs) in solution. Here, we extend the 1-D soluble supramolecular assembly to 3-D hydrogels to investigate the effect of the supramolecular nanostructure and its rheological properties on the antimicrobial activity of self-assembled hydrogels. Among designed MDPs, the bactericidal activity of peptide hydrogels was found to follow an opposite trend to that in solution. Improved antimicrobial activity of self-assembled peptide hydrogels is dictated by the combined effect of supramolecular surface chemistry and storage modulus of the bulk materials, rather than the ability of individual peptides/peptide assemblies to penetrate bacterial cell membrane as observed in solution. The structure-property-activity relationship developed through this study will provide important guidelines for designing biocompatible peptide hydrogels with built-in antimicrobial activity for various biomedical applications.

  10. Antioxidant and antimicrobial activities of Saraca thaipingensis Cantley ex Prain

    Institute of Scientific and Technical Information of China (English)

    Supaluk Prachayasittikul; Apilak Worachartcheewan; Sakda Yainoy; Natthakaln Lomchoey; Paveena Kittiphatcharin; Somsak Ruchirawat; Virapong Prachayasittikul

    2012-01-01

    Objective: To investigate antioxidant and antimicrobial activities of Saraca thaipingensis Cantley ex Prain; and isolation of its flower extracts. Methods: The plant species (flowers, leaves, and twigs) were extracted by hexane, dichloromethane, ethyl acetate and methanol; and tested for antioxidant activity (DPPH assay) and antimicrobial activity (agar dilution method) against twenty-seven strains of microorganisms; gram positive and gram negative bacteria, and diploid fungus. Bioactive constituents were isolated by column chromatography. Results: The plant extracts has been firstly reported to display strong antioxidant activity and antimicrobial activity selective against gram positive bacteria (Corynebacterium diphtheriae NCTC 10356 and Streptococcus pyogenes) with MIC of 256 μg/mL. Stigmasterol and a mixture of triterpenoids and phenolic compounds were isolated from the flower extracts. Conclusions: The study revealed that the S. thaipingensis is a new source of natural antioxidants and antimicrobials with potential for medicinal uses.

  11. Screening of some Malay medicated oils for antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Khalid Khalisanni

    2010-01-01

    Full Text Available Oils from six Malay medicated oils, used traditionally in the treatment of infectious and septic diseases in humans, were tested for their antimicrobial property. The aim was to evaluate the antimicrobial properties of six Malay medicated oils against certain microbial isolates. Locally available Malay medicated oils were checked for their antimicrobial activities using six species of bacteria: E. coli, Salmonella spp., Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus, Bacillus subtilis and 2 fungi with 1 yeast (Aspergillus niger, Penicillum spp. and Candida albicans. Clove oil showed the highest antibacterial activity followed, respectively, by 'bunga merah', cajaput, nutmeg, lemon grass and 'gamat' oil. Clove oil and lemon grass showed anticandidal activity. The Malay medicated oil studies did not show any antifungal activity. The study shows that Malay medicated oils, like antibiotics, have antimicrobial activities against some microorganisms.

  12. Chemical constituents and antimicrobial activity of Goniothalamus ...

    African Journals Online (AJOL)

    AG Siti Humeirah, MA Nor Azah, M Mastura, J Mailina, JA Saiful, H Muhajir, AM Puad ... Chromatography/Mass Spectrometry (GC-MS) using CBP-5 capillary column ... antimicrobial properties against gram positive and gram negative bacteria, ...

  13. Antimicrobial activity of poly(acrylic acid) block copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Gratzl, Günther, E-mail: guenther.gratzl@jku.at [Johannes Kepler University Linz, Institute for Chemical Technology of Organic Materials, Altenberger Str. 69, 4040 Linz (Austria); Paulik, Christian [Johannes Kepler University Linz, Institute for Chemical Technology of Organic Materials, Altenberger Str. 69, 4040 Linz (Austria); Hild, Sabine [Johannes Kepler University Linz, Institute of Polymer Science, Altenberger Str. 69, 4040 Linz (Austria); Guggenbichler, Josef P.; Lackner, Maximilian [AMiSTec GmbH and Co. KG, Leitweg 13, 6345 Kössen, Tirol (Austria)

    2014-05-01

    The increasing number of antibiotic-resistant bacterial strains has developed into a major health problem. In particular, biofilms are the main reason for hospital-acquired infections and diseases. Once formed, biofilms are difficult to remove as they have specific defense mechanisms against antimicrobial agents. Antimicrobial surfaces must therefore kill or repel bacteria before they can settle to form a biofilm. In this study, we describe that poly(acrylic acid) (PAA) containing diblock copolymers can kill bacteria and prevent from biofilm formation. The PAA diblock copolymers with poly(styrene) and poly(methyl methacrylate) were synthesized via anionic polymerization of tert-butyl acrylate with styrene or methyl methacrylate and subsequent acid-catalyzed hydrolysis of the tert-butyl ester. The copolymers were characterized via nuclear magnetic resonance spectroscopy (NMR), size-exclusion chromatography (SEC), Fourier transform infrared spectroscopy (FTIR), elemental analysis, and acid–base titrations. Copolymer films with a variety of acrylic acid contents were produced by solvent casting, characterized by atomic force microscopy (AFM) and tested for their antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The antimicrobial activity of the acidic diblock copolymers increased with increasing acrylic acid content, independent of the copolymer-partner, the chain length and the nanostructure. - Highlights: • Acrylic acid diblock copolymers are antimicrobially active. • The antimicrobial activity depends on the acrylic acid content in the copolymer. • No salts, metals or other antimicrobial agents are needed.

  14. preliminary phytochemical screening and antimicrobial activity of ...

    African Journals Online (AJOL)

    DR. AMINU

    extracts demonstrated promising activity against the test organisms. The activity of methanol ... concentration (MIC) showed that methanol and ethyl acetate extracts had the lowest MIC value. (10mg/ml) ... seeds of avocado pear was found to be greater than. 70% (Soong ..... Hill, A. F. (1952): Economic Botany: A Textbook of.

  15. Antimicrobial Activity of Tamarindus indica Linn | Doughari | Tropical ...

    African Journals Online (AJOL)

    ... against some common gram negative and gram positive bacteria and fungi. ... of the plant and the effect of temperature and pH on its antimicrobial activity. ... of antibiotics that could be useful for infectious disease chemotherapy and control.

  16. Screening of the Antimicrobial Activities of Some Plants Used ...

    African Journals Online (AJOL)

    Screening of the Antimicrobial Activities of Some Plants Used Traditionally in Ethiopia for the Treatment of Skin Disorders. ... Ethiopian Pharmaceutical Journal ... Pseudomonas aeruginosa and Streptococcus pyogenes with the exception of ...

  17. Release and antimicrobial activity of silver sulphadiazine from different creams

    NARCIS (Netherlands)

    Saene, J.J.M.; Trooster, J.F.G.; Meulenhoff, A.M.C.; Lerk, C.F.; Bult, A.

    1987-01-01

    The release and antimicrobial activity of silver sulphadiazine from five different creams were studied: unguentum emulsilicans aquosum, unguentum hydrophy. licum non ionogenicum, paraffin cream (15 per cent), a homemade preparation and a commercially available preparation (Flamazine). A diffusion ce

  18. Synthesis and Antimicrobial Activity of Some New Formazan Derivatives

    Directory of Open Access Journals (Sweden)

    S. I. Marjadi

    2009-01-01

    Full Text Available A series of new substituted formazan derivatives has been synthesized from corresponding aryl diazonium chloride and Schiff base in pyridine. The synthesized compounds were identified by spectral studies and screened for their antimicrobial activities.

  19. Synthesis and Antimicrobial Activity of Some New Formazan Derivatives

    OpenAIRE

    S. I. Marjadi; Solanki, J. H.; A.L. Patel

    2009-01-01

    A series of new substituted formazan derivatives has been synthesized from corresponding aryl diazonium chloride and Schiff base in pyridine. The synthesized compounds were identified by spectral studies and screened for their antimicrobial activities.

  20. Screening marine organisms for antimicrobial activity against clinical pathogens

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi; Wahidullah, S.; Tonima, K.; DeSouza, L.

    ) and Hospital. Antimicrobial assay Antibacterial activity of different extracts was assessed using standard disc-diffusion assay on marine agar as described earlier5. Extracts and fractions, each, were dissolved in the respective solvents and loaded...

  1. Antimicrobial activity of Dracaena cinnabari resin from Soqotra ...

    African Journals Online (AJOL)

    PROF ADEWUNMI

    honeybee was studied using the agar disc diffusion method. ... Key words: Antimicrobial Activity, Dracaena cinnabari, Human pathogens, Minimum Inhibitory ... polymicrobial culture, no study investigating the effect of D. cinnabari resin on the ...

  2. Evidence for antimicrobial activity associated with common house spider silk

    Directory of Open Access Journals (Sweden)

    Wright Simon

    2012-06-01

    Full Text Available Abstract Background Spider silk is one of the most versatile materials in nature with great strength and flexibility. Native and synthetically produced silk has been used in a wide range of applications including the construction of artificial tendons and as substrates for human cell growth. In the literature there are anecdotal reports that suggest that native spider silk may also have antimicrobial properties. Findings In this study we compared the growth of a Gram positive and a Gram negative bacterium in the presence and absence of silk produced by the common house spider Tegenaria domestica. We demonstrate that native web silk of Tegenaria domestica can inhibit the growth of the Gram positive bacterium, Bacillus subtilis. No significant inhibition of growth was detected against the Gram negative bacterium, Escherichia coli. The antimicrobial effect against B. subtilis appears to be short lived thus the active agent potentially acts in a bacteriostatic rather than bactericidal manner. Treatment of the silk with Proteinase K appears to reduce the ability to inhibit bacterial growth. This is consistent with the active agent including a protein element that is denatured or cleaved by treatment. Tegenaria silk does not appear to inhibit the growth of mammalian cells in vitro thus there is the potential for therapeutic applications.

  3. Synthesis and Antimicrobial Activity of 1,2-Benzothiazine Derivatives

    Directory of Open Access Journals (Sweden)

    Chandani Patel

    2016-06-01

    Full Text Available A number of 1,2-benzothiazines have been synthesized in a three-step process. Nine chalcones 1–9 bearing methyl, fluoro, chloro and bromo substituents were chlorosulfonated with chlorosulfonic acid to generate the chalcone sulfonyl chlorides 10–18. These were converted to the dibromo compounds 19–27 through reaction with bromine in glacial acetic acid. Compounds 19–27 were reacted with ammonia, methylamine, ethylamine, aniline and benzylamine to generate a library of 45 1,2-benzothiazines 28–72. Compounds 28–72 were evaluated for their antimicrobial activity using broth microdilution techniques against two Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus and two Gram-negative bacteria (Proteus vulgaris and Salmonella typhimurium. The results demonstrated that none of the compounds showed any activity against Gram-negative bacteria P. vulgaris and S. typhimurium; however, compounds 31, 33, 38, 43, 45, 50, 53, 55, 58, 60, 63 and 68 showed activity against Gram-positive bacteria Bacillus subtilis and Staphylococcous aureus. The range of minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC was 25–600 µg/mL, though some of the MIC and MBC concentrations were high, indicating weak activity. Structure activity relationship studies revealed that the compounds with a hydrogen atom or an ethyl group on the nitrogen of the thiazine ring exerted antibacterial activity against Gram-positive bacteria. The results also showed that the compounds where the benzene ring of the benzoyl moiety contained a methyl group or a chlorine or bromine atom in the para position showed higher antimicrobial activity. Similar influences were identified where either a bromine or chlorine atom was in the meta position.

  4. Antimicrobial activity and chemometric modelling of South African propolis.

    Science.gov (United States)

    Suleman, T; van Vuuren, S; Sandasi, M; Viljoen, A M

    2015-10-01

    This study reports on the inhibitory and bactericidal properties of 39 South African (SA) propolis samples and three propolis samples from Brazil. Ethanolic extracts of propolis (EEP) were prepared and their antimicrobial activities tested using the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. Some samples displayed substantial antimicrobial activity with MIC and MBC values as low as 6 μg ml(-1) against Staphylococcus aureus. The correlation between liquid chromatography-mass spectrometry (LC-MS) chemical data and the antimicrobial activity of propolis extracts was investigated using multivariate data analysis tools. Orthogonal projections to latent structures (OPLS) models were created for the two Gram-positive bacteria (Enterococcus faecalis and S. aureus) and Candida albicans. Using the S-plot function, it was possible to identify the bioactive constituents in propolis as chrysin, pinocembrin, galangin and pinobanksin-3-O-acetate. The SA propolis samples tested displayed noteworthy antimicrobial activity, favourably comparable to that of the Brazilian comparator and 'gold standard'. The observed antimicrobial activity of SA propolis can possibly be attributed to its flavonoid content. Based on the good antimicrobial activity observed for SA propolis, this natural resource shows promise and should be considered for development which may contribute to growing the bio-economy in the region. © 2015 The Society for Applied Microbiology.

  5. Exposure to Cigarette Smoke Disrupts CCL20-Mediated Antimicrobial Activity in Respiratory Epithelial Cells.

    Science.gov (United States)

    Crane-Godreau, Mardi A; Maccani, Matthew A; Eszterhas, Susan K; Warner, Sandra L; Jukosky, James A; Fiering, Steven

    2009-01-01

    Cigarette smoke (CS) exposure is known to increase infection rates, but the mechanisms are not well understood. These studies tested the hypothesis that CS exposure would impair antimicrobial activity of apical conditioned media from human airway (BEAS-2B) cultures by reducing induction and release of the antimicrobial peptide CCL20. BEAS-2B cultures were exposed to CS extract and assayed for temporal and physical characteristics of release as well as for antimicrobial activity. E. coli were exposed to Beas-2B-conditioned media (BCM) and subsequent bacterial colonies were enumerated. In time course studies TLR-agonist-induced CCL20 transcription and release were rapid, of short duration and release was consistently targeted to the apical/luminal compartment. Cells treated with CS extract had diminished release of CCL20 under both constitutive and toll-like receptor (TLR) agonist stimulating conditions. Exposure of the cells to CS significantly reduced the antimicrobial activity in BCM and neutralizing antibodies to CCL20 brought antibacterial activity back to baseline levels demonstrating that antimicrobial activity in this culture system was primarily attributable to CCL20. These studies add to the understanding of CCL20 as a mucosal antimicrobial and improve insight into a likely mechanism linking infection to CS exposure.

  6. Evaluation of the antimicrobial activity of dentifrices on human oral bacteria.

    Science.gov (United States)

    Haraszthy, Violet I; Zambon, Joseph J; Sreenivasan, Prem K

    2010-01-01

    In vitro testing of antimicrobial agents is an important tool in the testing hierarchy, and may provide interesting insights into their potential clinical efficacy. Agents with demonstrable in vitro antimicrobial activity may be effective against the same microorganisms in vivo, whereas agents without demonstrable in vitro antimicrobial activity are unlikely to exhibit in vivo antimicrobial activity. In addition, these methods may also be useful in screening antimicrobial agents in product formulations because such agents with both in vitro and in vivo activity may have reduced antimicrobial effects when formulated into a dentifrice. Accordingly, this study examined the in vitro and ex vivo antimicrobial activity of three commercial dentifrices: one formulated with 0.243% sodium fluoride (Crest Cavity Protection Toothpaste-Regular); one with 0.454% stannous fluoride, sodium hexametaphosphate, and zinc lactate (Crest Pro-Health), and one with 0.3% triclosan, 2.0% PVM/MA copolymer, and 0.243% sodium fluoride (Colgate Total). The minimum inhibitory concentration (MIC) of each dentifrice was determined for resident oral bacterial species, including bacteria that are associated with dental caries; periodontitis, and oral halitosis. Evaluations were performed on individual laboratory strains, and on oral bacteria from supragingival plaque samples obtained from 10 adults and from oral rinse samples obtained from 18 adults. The lowest MICs against the oral strains and human samples, i.e., greatest antimicrobial activity, were seen for the triclosan/ copolymer dentifrice. There was, in general, a four-fold difference in MICs between the triclosan/copolymer dentifrice and the stannous fluoride/sodium hexametaphosphate/zinc lactate dentifrice. The triclosan/copolymer dentifrice significantly inhibited periodontal pathogens, such as Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum. In ex vivo tests measuring antimicrobial effects, the

  7. Antimicrobial activity and phytochemical characterization of Carya illinoensis.

    Science.gov (United States)

    Bottari, Nathieli Bianchin; Lopes, Leonardo Quintana Soares; Pizzuti, Kauana; Filippi Dos Santos Alves, Camilla; Corrêa, Marcos Saldanha; Bolzan, Leandro Perger; Zago, Adriana; de Almeida Vaucher, Rodrigo; Boligon, Aline Augusti; Giongo, Janice Luehring; Baldissera, Matheus Dellaméa; Santos, Roberto Christ Vianna

    2017-03-01

    Carya illinoensis is a widespread species, belonging to the Juglandaceae family, commonly known as Pecan. Popularly, the leaves have been used in the treatment of smoking as a hypoglycemic, cleansing, astringent, keratolytic, antioxidant, and antimicrobial agent. The following research aimed to identify for the first time the phytochemical compounds present in the leaves of C. illinoensis and carry out the determination of antimicrobial activity of aqueous and ethanolic extracts. The antimicrobial activity was tested against 20 microorganisms by determining the minimum inhibitory concentration (MIC). Phenolic acids (gallic acid and ellagic acid), flavonoids (rutin), and tannins (catechins and epicatechins) were identified by HPLC-DAD and may be partially responsible for the antimicrobial activity against Gram-positive, Gram-negative, and yeast. The results showed MIC values between 25 mg/mL and 0.78 mg/mL. The extracts were also able to inhibit the production of germ tubes by Candida albicans.

  8. The antimicrobial activity of the Cnicus benedictus L. extracts

    Directory of Open Access Journals (Sweden)

    Annamaria PALLAG

    2009-05-01

    Full Text Available Our goal was to test the antimicrobial effect of the aqueous solutions obtained from the soft extract of Cnicus benedictus L. (Asteraceae family flowers. The test was performed on Mueller - Hinton and blood-agar culture medium, on 8 standardized bacterial strains and microbiological strains obtained from infected secretions, using the diffusimetric method.The antimicrobial action of the plant extracts was confirmed by all bacterial tested strains, which presented inhibition zones, of approximately same values, at solutions with different concentrations. The values we obtained reveal significant differences of the intensity of the antimicrobial activity of the mature and immature flowers extract.

  9. Antimicrobial activity of thin metallic silver flakes, waste products of a manufacturing process

    Institute of Scientific and Technical Information of China (English)

    Manuela Anzano; Alessandra Tosti; Marina Lasagni; Alfredo Campiglio; Demetrio Pitea; Elena Collina*

    2011-01-01

    The aim of the research was to develop new products and processes from a manufacturing waste from an Italian metallurgic company.The company produced thin silver metallic films and the production scraps were silver flakes.The possibility to use the silver flakes in water disinfection processes was studied.The antimicrobial activity of the flakes was investigated in batch using Escherichia coli as Gram-negative microorganism model.The flakes did not show any antimicrobial activity,so they were activated with two different processes:thermal activation in reducing atmosphere and chemical activation,obtaining,respectively,reduced flakes (RF) and chemical flakes (CF).The flakes,activated with either treatment,showed antimicrobial activity against E.coli.The kill rate was dependent on the type of activated flakes.The chemical flakes were more efficient than reduced flakes.The kill rate determined for 1 g of CF,1.0 ± 0.2min-1,was greater than the kill rate determined for 1 g of RF,0.069 + 0.004 min-1.This was confirmed also by the minimum inhibitory concentration values.It was demonstrated that the antimicrobial capability was dependent on flakes amount and on the type of aqueous medium.Furthermore,the flakes maintained their properties also when used a second time.Finally,the antimicrobial activities of flakes were tested in an effluent of a wastewater treatment plant where a variety of heterotrophic bacteria were present.

  10. Structure-activity relationship of a u-type antimicrobial microemulsion system.

    Directory of Open Access Journals (Sweden)

    Hui Zhang

    Full Text Available The structure-activity relationship of a U-type antimicrobial microemulsion system containing glycerol monolaurate and ethanol at a 1∶1 mass ratio as oil phase and Tween 20 as surfactant were investigated along a water dilution line at a ratio of 80∶20 mass% surfactant/oil phase, based on a pseudo-ternary phase diagram. The differential scanning calorimetry results showed that in the region of up to 33% water, all water molecules are confined to the hydrophilic core of the reverse micelles, leading to the formation of w/o microemulsion. As the water content increases, the water gains mobility, and transforms into bicontinuous in the region of 33-39% water, and finally the microemulsion become o/w in the region of above 39% water. The microstructure characterization was confirmed by the dynamic light scattering measurements and freeze-fracture transmission electron microscope observation. The antimicrobial activity assay using kinetics of killing analysis demonstrated that the microemulsions in w/o regions exhibited relatively high antimicrobial activity against Escherichia coli and Staphylococcus aureus due to the antimicrobial oil phase as the continuous phase, while the antimicrobial activity started to decrease when the microemulsions entered the bicontinuous region, and decreased rapidly as the water content increased in the o/w region, as a result of the dilution of antimicrobial oil droplets in the aqueous continuous phase.

  11. [In vitro study of antimicrobial activity of lactoferrins from various sources].

    Science.gov (United States)

    Grammatikova, N E; Rezvan, S P; Nemtsova, E R; Bezborodova, O A; Tutykhina, I L; Naroditskiĭ, B S; Iakubovskaia, R I

    2010-01-01

    Comparative antimicrobial activity of lactoferrins from various sources (native lactoferrin from Laprot, human hololactoferrin, recombinant human lactoferrin isolated from the cultural medium of permissive cell culture transfected using pseudoadenovirus nanostructure with the human lactoferrin gene, and native bovine lactoferrin) was studied to prove the possibility of their use for development of antimicrobial drugs. It was shown that all the substances were active against the Bacillus standard strains. The antibacterial activity was almost independent of the degree of saturation the lactoferrin molecules with Fe3+. The native human lactoferrin was more active than hololactoferrin against Candida when evaluated by the minimum inhibitory concentration (MIC). Fe(3+)-Non aturated recombinant human lactoferrin demonstrated the antimicrobial activity (by MIC) similar to that of the native human lactoferrin. The results showed that native and recombinant human lactoferrins might be used for the development of intravenous and intracavitary dosage forms, while the native bovine lactoferrin could be useful in development of oral drugs.

  12. Activity of 10 antimicrobial agents against intracellular Rhodococcus equi.

    Science.gov (United States)

    Giguère, Steeve; Berghaus, Londa J; Lee, Elise A

    2015-08-05

    Studies with facultative intracellular bacterial pathogens have shown that evaluation of the bactericidal activity of antimicrobial agents against intracellular bacteria is more closely associated with in vivo efficacy than traditional in vitro susceptibility testing. The objective of this study was to determine the relative activity of 10 antimicrobial agents against intracellular Rhodococcus equi. Equine monocyte-derived macrophages were infected with virulent R. equi and exposed to erythromycin, clarithromycin, azithromycin, rifampin, ceftiofur, gentamicin, enrofloxacin, vancomycin, imipenem, or doxycycline at concentrations achievable in plasma at clinically recommended dosages in foals. The number of intracellular R. equi was determined 48h after infection by counting colony forming units (CFUs). The number of R. equi CFUs in untreated control wells were significantly higher than those of monolayers treated with antimicrobial agents. Numbers of R. equi were significantly lower in monolayers treated with enrofloxacin followed by those treated with gentamicin, and vancomycin, when compared to monolayers treated with other antimicrobial agents. Numbers of R. equi in monolayers treated with doxycycline were significantly higher than those of monolayers treated with other antimicrobial agents. Differences in R. equi CFUs between monolayers treated with other antimicrobial agents were not statistically significant. Enrofloxacin, gentamicin, and vancomycin are the most active drugs in equine monocyte-derived macrophages infected with R. equi. Additional studies will be needed to determine if these findings correlate with in vivo efficacy. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Development and evaluation of antimicrobial activated carbon fiber filters using Sophora flavescens nanoparticles.

    Science.gov (United States)

    Sim, Kyoung Mi; Kim, Kyung Hwan; Hwang, Gi Byoung; Seo, SungChul; Bae, Gwi-Nam; Jung, Jae Hee

    2014-09-15

    Activated carbon fiber (ACF) filters have a wide range of applications, including air purification, dehumidification, and water purification, due to their large specific surface area, high adsorption capacity and rate, and specific surface reactivity. However, when airborne microorganisms such as bacteria and fungi adhere to the carbon substrate, ACF filters can become a source of microbial contamination, and their filter efficacy declines. Antimicrobial treatments are a promising means of preventing ACF bio-contamination. In this study, we demonstrate the use of Sophora flavescens in antimicrobial nanoparticles coated onto ACF filters. The particles were prepared using an aerosol process consisting of nebulization-thermal drying and particle deposition. The extract from S. flavescens is an effective, natural antimicrobial agent that exhibits antibacterial activity against various pathogens. The efficiency of Staphylococcus epidermidis inactivation increased with the concentration of S. flavescens nanoparticles in the ACF filter coating. The gas adsorption efficiency of the coated antimicrobial ACF filters was also evaluated using toluene. The toluene-removal capacity of the ACF filters remained unchanged while the antimicrobial activity was over 90% for some nanoparticle concentrations. Our results provide a scientific basis for controlling both bioaerosol and gaseous pollutants using antimicrobial ACF filters coated with S. flavescens nanoparticles.

  14. Comparative Evaluation of the Antimicrobial Activity of Different Antimicrobial Peptides against a Range of Pathogenic Bacteria

    DEFF Research Database (Denmark)

    Ebbensgaard, Anna Elisabeth; Mordhorst, Hanne; Overgaard, Michael Toft

    2015-01-01

    The rapid emergence of resistance to classical antibiotics has increased the interest in novel antimicrobial compounds. Antimicrobial peptides (AMPs) represent an attractive alternative to classical antibiotics and a number of different studies have reported antimicrobial activity data of various...... AMPs, but there is only limited comparative data available. The mode of action for many AMPs is largely unknown even though several models have suggested that the lipopolysaccharides (LPS) play a crucial role in the attraction and attachment of the AMP to the bacterial membrane in Gram......-negative bacteria. We compared the potency of Cap18, Cap11, Cap11-1-18m2, Cecropin P1, Cecropin B, Bac2A, Bac2A-NH2, Sub5-NH2, Indolicidin, Melittin, Myxinidin, Myxinidin-NH2, Pyrrhocoricin, Apidaecin and Metalnikowin I towards Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli...

  15. Antimicrobial Activity Investigation on Wuyiencin Fractions of Different Polarity

    Directory of Open Access Journals (Sweden)

    Zengjie Cui

    2010-04-01

    Full Text Available The aim of this study was to evaluate the antimicrobial activity of Wuyiencin fractions with different polarities against six indicator microorganisms: Rhodotorula rubra, Bacillus subtilis, Bacillus megaterium, Escherichia coli, Cladosporium fulvum and Staphylococcus aureus. The fermentation broth of Wuyiencin was submitted to AB-8 macroporous adsorptive resin and fractionated with solvents of different polarity. The fraction eluted with water had remarkably antimicrobial activity against all the microorganisms investigated except for C. fulvum and S. aureus (MIC ≤ 0.0625 mg/mL, probably due to the presence of active components. The fraction eluted with methanol showed potential antimicrobial activity against all the test microorganisms except for R.rubra, with MIC values of0.5 and 2 mg/mL. In conclusion, fractions eluted with water and methanol, respectively, represent the main active-part of Wuyiencin, and could be emphasized for agricultural applications in the future.

  16. Phytochemical characterization and antimicrobial activity of Curcuma xanthorrhiza Roxb.

    Institute of Scientific and Technical Information of China (English)

    Mary Helen PA; Susheela Gomathy K; Jayasree S; Nizzy AM; Rajagopal B; Jeeva S

    2012-01-01

    Objective: To study the antimicrobial activity and phytochemical characterization of essential oil isolated from the rhizome of Curcuma xanthorrhiza against pathogenic bacteria and fungi.Methods:Fresh rhizomes of Curcuma xanthorrhiza were subjected to hydro distillation process to obtain essential oil and characterized by Gas Chromatography- Mass Spectroscopy (GC-MS). The essential oil was evaluated for antibacterial and antifungal activity against thirteen pathogenic bacteria and six fungi by the disc diffusion method. Results: GC – MS analysis of the essential oil extracted from the rhizome of Curcuma xanthorrhiza contained the derivatives of xanthorihizol, camphene and curcumene, monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene, hydrocarbons and other minor compounds. The antimicrobial activity of the oil showed significant inhibitory activity against the human pathogenic bacteria, no activity was observed against the fungi Aspergillus niger and Fusarium oxysporum. Conclusions: The findings of the present study indicate that the rhizome extract of Curcuma xanthorrhiza possess secondary metabolites and potential to develop antimicrobial drugs.

  17. 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.

  18. Actividad antimicrobiana de Verbesina encelioides Antimicrobial activity of Verbesina encelioides

    Directory of Open Access Journals (Sweden)

    M.S Toribio

    2005-12-01

    : Staphylococcus aureus, S. epidermidis, S. intermedius, Pseudomonas aeruginosa, Streptococcus agalactiae, Salmonella typhimurium, Citrobacter freundii, Proteus spp., Escherichia coli, Candida albicans. These results, obtained under our working conditions, demonstrate that the methanolic extract of the heads of Verbesina encelioides has a more notorious antimicrobial activity against Gram positive microorganisms and Candida albicans than against Gram negative bacteria, having no activity against Citrobacter freundii.

  19. Antimicrobial Activity of Ceftriaxone Compared with Cefotaxime in the Presence of Serum Albumin

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    Swapan K Nath

    1995-01-01

    Full Text Available The effect of serum albumin on the antimicrobial activity of ceftriaxone, cefotaxime, and a 1:1 ratio of cefotaxime and its desacetyl metabolite against nonpseudomonal Gram-negative bacilli was determined. Antimicrobial activity of drugs was evaluated by measuring minimum inhibitory (mic and bactericidal (mbc concentrations in broth with and without human serum albumin. The analysis of logarithmically transformed mean mics and mbcs showed that there was a highly significant interaction between drug and serum albumin (P<0.0001. The inhibitory and bactericidal activities were greatest for cefotaxime followed by cefotaxime/desacetylcefotaxime and ceftriaxone (P<0.01. Time-kill kinetics demonstrated that ceftriaxone was less bactericidal than cefotaxime in broth with albumin. On the basis of these results it was concluded that the in vitro antimicrobial activity of ceftriaxone compared with that of cefotaxime was significantly diminished in the presence of serum albumin.

  20. Activity and Mechanism of Antimicrobial Peptide-Mimetic Amphiphilic Polymethacrylate Derivatives

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    Kenichi Kuroda

    2011-09-01

    Full Text Available Cationic amphiphilic polymethacrylate derivatives (PMAs have shown potential as a novel class of synthetic antimicrobials. A panel of PMAs with varied ratios of hydrophobic and cationic side chains were synthesized and tested for antimicrobial activity and mechanism of action. The PMAs are shown to be active against a panel of pathogenic bacteria, including a drug-resistant Staphylococcus aureus, compared to the natural antimicrobial peptide magainin which did not display any activity against the same strain. The selected PMAs with 47–63% of methyl groups in the side chains showed minimum inhibitory concentrations of ≤2–31 µg/mL, but cause only minimal harm to human red blood cells. The PMAs also exhibit rapid bactericidal kinetics. Culturing Escherichia coli in the presence of the PMAs did not exhibit any potential to develop resistance against the PMAs. The antibacterial activities of PMAs against E. coli and S. aureus were slightly reduced in the presence of physiological salts. The activity of PMAs showed bactericidal effects against E. coli and S. aureus in both exponential and stationary growth phases. These results demonstrate that PMAs are a new antimicrobial platform with no observed development of resistance in bacteria. In addition, the PMAs permeabilized the E. coli outer membrane at polymer concentrations lower than their MIC values, but they did not show any effect on the bacterial inner membrane. This indicates that mechanisms other than membrane permeabilization may be the primary factors determining their antimicrobial activity.

  1. Making Waves: Seismic Waves Activities and Demonstrations

    Science.gov (United States)

    Braile, S. J.; Braile, L. W.

    2011-12-01

    The nature and propagation of seismic waves are fundamental concepts necessary for understanding the exploration of Earth's interior structure and properties, plate tectonics, earthquakes, and seismic hazards. Investigating seismic waves is also an engaging approach to learning basic principles of the physics of waves and wave propagation. Several effective educational activities and demonstrations are available for teaching about seismic waves, including the stretching of a spring to demonstrate elasticity; slinky wave propagation activities for compressional, shear, Rayleigh and Love waves; the human wave activity to demonstrate P- and S- waves in solids and liquids; waves in water in a simple wave tank; seismic wave computer animations; simple shake table demonstrations of model building responses to seismic waves to illustrate earthquake damage to structures; processing and analysis of seismograms using free and easy to use software; and seismic wave simulation software for viewing wave propagation in a spherical Earth. The use of multiple methods for teaching about seismic waves is useful because it provides reinforcement of the fundamental concepts, is adaptable to variable classroom situations and diverse learning styles, and allows one or more methods to be used for authentic assessment. The methods described here have been used effectively with a broad range of audiences, including K-12 students and teachers, undergraduate students in introductory geosciences courses, and geosciences majors.

  2. The Medicinal Plant of Mimusops Elengi (Sapodaceae in Antimicrobial Activities

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    Kannadhasan M.

    2016-07-01

    Full Text Available The selected study area for this study is Pachaimalai Hills, situated in Eastern ghats of Tamil Nadu. This study was focussed on the antimicrobial activity of Mimosopselengi, one of the medicinal plant belongs to the family sapotaceae. It is a tropically distributed the highly medicinal plant. Antimicrobial activities and extracts of petroleum ether, Ethyl acetate and methanol were also found to be better with respect to inhibitory function against the two fungal species, Fusarium oxysporum and Aspergillus flavus. The study scientifically validates the use of plant in traditional and ethno medicine. Three solvents such as Petroleum ether, Ethyl acetate and Ethanol were used to take plant extract. These extracts were studied for antimicrobial activity against two gram positive bacterial strains such as Bacillus substilis andBacillus thuriengensis and two gram negative bacterial strains such as Klebsiella pneumonia and Escherichia coli. This study also extended to find antifungal activity against four fungal strains.

  3. Guidance manual for conducting technology demonstration activities

    Energy Technology Data Exchange (ETDEWEB)

    Jolley, Robert L.; Morris, Michael I.; Singh, Suman P.N.

    1991-12-01

    This demonstration guidance manual has been prepared to assist Martin Marietta Energy Systems, Inc. (Energy Systems), staff in conducting demonstrations. It is prepared in checklist style to facilitate its use and assumes that Energy Systems personnel have project management responsibility. In addition to a detailed step-by-step listing of procedural considerations, a general checklist, logic flow diagram, and several examples of necessary plans are included to assist the user in developing an understanding of the many complex activities required to manage technology demonstrations. Demonstrations are pilot-scale applications of often innovative technologies to determine the commercial viability of the technologies to perform their designed function. Demonstrations are generally conducted on well-defined problems for which existing technologies or processes are less than satisfactory in terms of effectiveness, cost, and/or regulatory compliance. Critically important issues in demonstration management include, but are not limited to, such factors as communications with line and matrix management and with the US Department of Energy (DOE) and Energy Systems staff responsible for management oversight, budgetary and schedule requirements, regulatory compliance, and safety.

  4. ANTIMICROBIAL ACTIVITY OF THE FRUIT-SEEDS MADHUCA LONGIFOLIA (KOENIG

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    Chirantan S Chakma

    2011-09-01

    Full Text Available The investigation was carried out to study the antibacterial activity of the Madhuca longifolia(Koenig in gram positive and gram negative organism.. Antimicrobial activity of the acetone and aqueous extracts of M.longifolia were determined against various pathogenic bacteria. The extracts were tested against various bacteria like Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginos, .E.coli by disk diffusion method. Minimum Inhibitory Concentration (MIC values of both extracts were determined. It is concluded that acetone extract exhibited significant antimicrobial activity. The study lends scientific support for it’s use in folk medicine.

  5. Fractionation of Mastic Gum in Relation to Antimicrobial Activity

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    Mohammad Sharif Sharifi

    2009-04-01

    Full Text Available Mastic gum is a viscous light-green liquid obtained from the bark of Pistacia lentiscus var. chia. which belongs to the Anacardiaceae family. The gum has been fractionated to investigate the antimicrobial activity of the whole gum and its fractions against various strains of Helicobacter pylori. The polymeric gum fraction was separated from the essential oil and the resin (trunk exudates without essential oil to assess and compare the anti-H. pylori activity of the polymer fraction against lower molecular weight fractions, the gum itself and masticated gum. The polymer fraction was also oxidized and assessed for antimicrobial activity.

  6. Antimicrobial activity of rhodanine-3-acetic acid derivatives.

    Science.gov (United States)

    Krátký, Martin; Vinšová, Jarmila; Stolaříková, Jiřina

    2017-03-15

    Twenty-four 2-(4-oxo-2-thioxothiazolidin-3-yl)acetic acid (rhodanine-3-acetic acid)-based amides, esters and 5-arylalkylidene derivatives were synthesized, characterized and evaluated as potential antimicrobial agents against a panel of bacteria, mycobacteria and fungi. All of the derivatives were active against mycobacteria. N-(4-Chlorophenyl)-2-[5-(2-hydroxybenzylidene)-4-oxo-2-thioxothiazolidin-3-yl]acetamide demonstrated the highest activity against Mycobacterium tuberculosis with minimum inhibitory concentrations (MIC) of 8-16μM. Non-tuberculous mycobacteria were the most susceptible to 2-[5-(2-hydroxybenzylidene)-4-oxo-2-thioxothiazolidin-3-yl]acetic acids (MIC values ⩾32μM). The highest antibacterial activity against Gram-positive bacteria including methicillin-resistant Staphylococcus aureus exhibited 4-(trifluoromethyl)phenyl 2-(4-oxo-2-thioxothiazolidin-3-yl)acetate (MIC⩾15.62μM). Several structure-activity relationships were identified. The activity against Gram-negative and fungal pathogens was marginal. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Unsaturated fatty acids lactose esters: cytotoxicity, permeability enhancement and antimicrobial activity.

    Science.gov (United States)

    Lucarini, Simone; Fagioli, Laura; Campana, Raffaella; Cole, Hannah; Duranti, Andrea; Baffone, Wally; Vllasaliu, Driton; Casettari, Luca

    2016-10-01

    Sugar based surfactants conjugated with fatty acid chains are an emerging broad group of highly biocompatible and biodegradable compounds with established and potential future applications in the pharmaceutical, cosmetic and food industries. In this work, we investigated absorption enhancing and antimicrobial properties of disaccharide lactose, monoesterified with unsaturated fatty acids through an enzymatic synthetic approach. After chemical and cytotoxicity characterizations, their permeability enhancing activity was demonstrated using intestinal Caco-2 monolayers through transepithelial electrical resistance (TEER) and permeability studies. The synthesized compounds, namely lactose palmitoleate (URB1076) and lactose nervonate (URB1077), were shown to exhibit antimicrobial activity versus eight pathogenic species belonging to Gram-positive, Gram-negative microorganisms and fungi.

  8. Antimicrobial Activity of Metabolites of Various Strains of Lactobacillus acidophilus

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    Hassan Pyar Ali Hassan

    2011-01-01

    Full Text Available The antimicrobial activity of metabolites of eight strains of Lactobacillus acidophilus (FTDC 2804, FTDC 0785, FTDC 8592, FTDC 1295, FTDC 4793, FTDC 4462, FTDC 0582 and FTDC 2916 against  Staphylococcus aureus (gram positive and Escherichia coli (gram negative, was examined and compared using agar well diffusion method.  Lactobacillus acidophilus was cultivated in two different types of dairy growth medium namely, full cream milk and skim milk. The results showed that the metabolites of all the eight strains had significant antimicrobial effect based on zone of inhibition results when compared to control. There was a statistically significant difference in the zone of inhibition data for Staphylococcus aureus and Escherichia coli among the metabolites of the eight strains cultivated in the two different growth medium. Certain L. acidophilus strains were more effective against  Staphylococcus aureus, while other strains were more effective against  Escherichia coli. On the other hand, the growth medium had no significant influence on the antimicrobial effect of metabolites of seven strains except  L. acidophilus FTDC 4462 against Escherichia coli. As for  Staphylococcus aureus, the growth medium only affected the antimicrobial effect of metabolite of strain  L. acidophilus FTDC 1295, but did not affect the antimicrobial effect of metabolites of the other seven strains. It can be concluded that L. acidophilus cultivated in dairy products produced metabolites with antimicrobial property, which could provide beneficial medicinal values to human.

  9. Antimicrobial activity of leaf extracts of Justicia adhatoda L. in comparison with vasicine

    Institute of Scientific and Technical Information of China (English)

    Rashmi Pa; Linu Mathew

    2012-01-01

    Objective: To ascertain the antimicrobial activity of methanolic leaf extracts of Justicia adhatoda and vasicine against Staphylococcus aureus, Streptococcus pyogenes, Serratia marcescens, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Cryptococcus neoformans and Aspergillus flavus. Methods: The antimicrobial activity of the concentrated leaf extracts of J. adhatoda was evaluated by determination of the diameter of zone of inhibition against bacteria and fungi. 25μg ml-1 concentration was used to check the antimicrobial activity of plant extracts and vasicine. Minimum inhibitory concentrations and minimum microbicidal concentrations were determined against all the pathogens. Sensitivity of the pathogens was also checked with four standard antibiotics, ciprofloxacin and ofloxacin for bacteria and nystatin and amphotericin B for fungi. Results: The phytochemical studies revealed the presence of alkaloids in the extracts were active against both bacteria and fungi. Studies on the minimum inhibitory concentration of the extracts on the test organisms showed that the lowest minimum inhibitory concentration and minimum microbicidal concentrations were demonstrated against Serratia marcescens, Escherichia coli and Pseudomonas aeruginosa and the highest minimum inhibitory concentration was exhibited against Staphylococcus aureus, Streptococcuspyogenes, Klebsiella pnuemoniae. Among fungi Aspergillus flavus showed lowest minimum inhibitory concentration whereas Candida albicans and Cryptococcus neoformans showed highest minimum inhibitory concentration. Conclusion: The present study revealed that J. adhatoda has broad spectrum of antimicrobial activity and a potential source of antimicrobial agents that could be useful for chemotherapy and control of infectious diseases.

  10. SCREENING OF ANTIMICROBIAL ACTIVITY AND GENES CODING POLYKETIDE SYNTHETASE AND NONRIBOSOMAL PEPTIDE SYNTHETASE OF ACTINOMYCETE ISOLATES

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    Silvia Kovácsová

    2013-12-01

    Full Text Available The aim of this study was to observe antimicrobial activity using agar plate diffusion method and screening genes coding polyketide synthetase (PKS-I and nonribosomal peptide synthetase (NRPS from actinomycetes. A total of 105 actinomycete strains were isolated from arable soil. Antimicrobial activity was demonstrated at 54 strains against at least 1 of total 12 indicator organisms. Antifungal properties were recorded more often than antibacterial properties. The presence of PKS-I and NRPS genes were founded at 61 of total 105 strains. The number of strains with mentioned biosynthetic enzyme gene fragments matching the anticipated length were 19 (18% and 50 (47% respectively. Overall, five actinomycete strains carried all the biosynthetical genes, yet no antimicrobial activity was found against any of tested pathogens. On the other hand, twenty-one strains showed antimicrobial activity even though we were not able to amplify any of the PKS or NRPS genes from them. Combination of the two methods showed broad-spectrum antimicrobial activity of actinomycetes isolated from arable soil, which indicate that actinomycetes are valuable reservoirs of novel bioactive compounds.

  11. Antimicrobial activity of yeasts against some pathogenic bacteria

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    Gamal Younis

    2017-08-01

    Full Text Available Aim: This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species. Materials and Methods: A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR for detection of khs (kievitone hydratase and pelA (pectate degrading enzyme genes. Results: The recovery rate of yeasts from sausage was 20% (2/10 followed by kareish cheese, processed cheese, and butter 10% (1/10 each as well as raw milk 9% (9/100, and fruit yoghurt 30% (6/20. Different yeast species were recovered, namely, Candida kefyr (5 isolates, Saccharomyces cerevisiae (4 isolates, Candida intermedia (3 isolates, Candida tropicalis (2 isolates, Candida lusitaniae (2 isolates, and Candida krusei (1 isolate. khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa. Conclusion: The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food.

  12. Antimicrobial Activity of Chitosan-Carbon Nanotube Hydrogels

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    Jayachandran Venkatesan

    2014-05-01

    Full Text Available In the present study, we have prepared chitosan-carbon nanotube (Chitosan-CNT hydrogels by the freeze-lyophilization method and examined their antimicrobial activity. Different concentrations of CNT were used in the preparation of Chitosan-CNT hydrogels. These differently concentrated CNT hydrogels were chemically characterized using Fourier Transform-Infrared Spectroscopy, Scanning Electron Microscopy and Optical microscopy. The porosity of the hydrogels were found to be >94%. Dispersion of chitosan was observed in the CNT matrix by normal photography and optical microscopy. The addition of CNT in the composite scaffold significantly reduced the water uptake ability. In order to evaluate antimicrobial activity, the serial dilution method was used towards Staphylococcus aureus, Escherichia coli and Candida tropicalis. The composite Chitosan-CNT hydrogel showed greater antimicrobial activity with increasing CNT concentration, suggesting that Chitosan-CNT hydrogel scaffold will be a promising biomaterial in biomedical applications.

  13. Thymus catharinae Camarda essential oil: β-cyclodextrin inclusion complexes, evaluation of antimicrobial activity.

    Science.gov (United States)

    Delogu, Giovanna; Juliano, Claudia Clelia Assunta; Usai, Marianna

    2016-09-01

    An efficient antimicrobial activity was evidenced in a complex β-cyclodextrin-essential oil of Thymus catharinae Camarda (carvacrol chemotype). The release of carvacrol with respect to the antimicrobial activity was calculated as function of time. The βCD-complex of the bioactive agent was obtained by a simple, efficient and non-expensive method without purification of the carvacrol chemotype essential oil. According to the starting stoichiometry of β-cyclodextrin with respect to carvacrol, two inclusion complexes were produced, 1:1 and 2:1, respectively. The results demonstrate that, although the antimicrobial activity of the essential oil of T. catharinae Camarda is remarkable but acts too quickly in some types of application, its inclusion in a bio-matrix allows a slower release and improves its effectiveness.

  14. Antimicrobial activity of submerged cultures of Chilean basidiomycetes.

    Science.gov (United States)

    Aqueveque, Pedro; Anke, Timm; Saéz, Katia; Silva, Mario; Becerra, José

    2010-10-01

    This study is part of a screening program aimed at searching for bioactive metabolites from Chilean basidiomycetes. Submerged cultivation of fungal mycelia in liquid media was evaluated for antimicrobial activity. A total of 148 strains were obtained in vitro. The extracts produced from submerged cultures were evaluated against bacteria and fungi. In the primary antimicrobial assay, approximately 60% of the extracts presented positive biological activity. The highest frequencies of active strains were from the orders Agaricales (31.0%), Polyporales (20.6%), Sterales (18.3%), Boletales (11.4%), and Cortinariales (9.1%). Antifungal activity was more pronounced than antibacterial activity. Twelve extracts that exhibited strong antimicrobial activity showed minimum inhibitory concentration (MIC) values of 50 µL/mL against Bacillus brevis and 25∼50 µL/mL against Penicillium notatum and Paecilomyces variotii. The biological activity of some strains did not vary considerably, regardless of the substrate or collection site whereas, for others, it showed marked variations. Differences in antimicrobial activities observed in the different fungal genera suggested that the ability to produce bioactive compounds is not homogenously distributed among basidiomycetes. The information obtained from this study reveals that Chilean basidiomycetes are able to generate small and/or large variations in the normal pathway of compounds production. Thus, it is necessary to evaluate this biological and chemical wealth, which could be an unsuspected reservoir of new and potentially useful molecules.

  15. Development of QSAR for antimicrobial activity of substituted benzimidazoles.

    Science.gov (United States)

    Vashist, N; Sambi, S S; Kumar, P; Narasimhan, B

    2015-05-01

    QSAR analysis has been done to correlate antimicrobial activity of substituted benzimidazole derivatives with their physicochemical parameters. Developed QSAR models have been cross validated using leave one out (LOO) method. Statistical parameters like probable error of the coefficient of correlation (PE), least square error (LSE), Friedman's lack of fit measure (LOF), standard error of prediction (SEP) and quality value (Q) were also used to cross validate the models. QSAR studies established the importance of WAP, Mlog P and UI in describing the antimicrobial activities of substituted benzimidazole derivatives.

  16. Synthesis, Isolation of Phenazine Derivatives and Their Antimicrobial Activities

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    Aunchalee NANSATHIT

    2009-01-01

    Full Text Available Antimicrobial activity of natural phenazine-1-carboxylic acid (PCA from Pseudomonas aeruginosa TISTR 781 and synthetic phenazine-5,10-dioxide (PDO, prepared by oxidation of the phenazine, were evaluated by in vitro disc diffusion and minimal inhibitory concentration (MIC methods. The results indicated that both phenazine derivatives differed clearly in their antimicrobial activity. PCA showed better efficacy against growth of Acidovorax avenae subsp. citrulli, Bacillus subtilis, Candida albicans, Escherichia coli and Xanthomonas campestris pv. vesicatoria than PDO at low concentrations of PCA (MIC; 17.44 - 34.87 ppm as an antimicrobial agent. In contrast, PDO acted as a stronger inhibitor than PCA when tested against Pseudomonas syringae and Enterobacter aerogenes. The last bacterial strain, Ralstonia solanacearum, can be suppressed by the same concentration of PCA and PDO (MIC; 62.50 ppm. The data provided beneficial information for choosing phenazine types to inhibit some general strains and plant pathogenic bacteria.

  17. Activity of antimicrobial peptide mimetics in the oral cavity: I. Activity against biofilms of Candida albicans.

    Science.gov (United States)

    Hua, J; Yamarthy, R; Felsenstein, S; Scott, R W; Markowitz, K; Diamond, G

    2010-12-01

    Naturally occurring antimicrobial peptides hold promise as therapeutic agents against oral pathogens such as Candida albicans but numerous difficulties have slowed their development. Synthetic, non-peptidic analogs that mimic the properties of these peptides have many advantages and exhibit potent, selective antimicrobial activity. Several series of mimetics (with molecular weight oral Candida strains as a proof-of-principle for their antifungal properties. One phenylalkyne and several arylamide compounds with reduced mammalian cytotoxicities were found to be active against C. albicans. These compounds demonstrated rapid fungicidal activity in liquid culture even in the presence of saliva, and demonstrated synergy with standard antifungal agents. When assayed against biofilms grown on denture acrylic, the compounds exhibited potent fungicidal activity as measured by metabolic and fluorescent viability assays. Repeated passages in sub-minimum inhibitory concentration levels did not lead to resistant Candida, in contrast to fluconazole. Our results demonstrate the proof-of principle for the use of these compounds as anti-Candida agents, and their further testing is warranted as novel anti-Candida therapies.

  18. [Isolation and antimicrobial activities of actinomycetes from vermicompost].

    Science.gov (United States)

    Wang, Xue-jun; Yan, Shuang-lin; Min, Chang-li; Yang, Yan

    2015-02-01

    In this paper, actinomycetes were isolated from vermicompost by tablet coating method. Antimicrobial activities of actinomycetes were measured by the agar block method. Strains with high activity were identified based on morphology and biochemical characteristics, as well as 16S rDNA gene sequence analysis. The results showed that 26 strains of actinomycetes were isolated, 16 of them had antimicrobial activities to the test strains which accounts for 61.54% of all strains. Among the 16 strains, the strain QYF12 and QYF22 had higher antimicrobial activity to Micrococcus luteus, with a formed inhibition zone of 27 mm and 31 mm, respectively. While the strain QYF26 had higher antimicrobial activity to Bacillus subtilis, and the inhibition zone diameter was 21 mm. Based on the identification of strains with high activity, the strain QYF12 was identified as Streptomyces chartreusis, the strain QYF22 was S. ossamyceticus and the strain QYF26 was S. gancidicus. This study provided a theoretical basis for further separate antibacterial product used for biological control.

  19. Antimicrobial and immunomodulatory activities of PR-39 derived peptides.

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    Edwin J A Veldhuizen

    Full Text Available The porcine cathelicidin PR-39 is a host defence peptide that plays a pivotal role in the innate immune defence of the pig against infections. Besides direct antimicrobial activity, it is involved in immunomodulation, wound healing and several other biological processes. In this study, the antimicrobial- and immunomodulatory activity of PR-39, and N- and C-terminal derivatives of PR-39 were tested. PR-39 exhibited an unexpected broad antimicrobial spectrum including several Gram positive strains such as Bacillus globigii and Enterococcus faecalis. Of organisms tested, only Staphylococcus aureus was insensitive to PR-39. Truncation of PR-39 down to 15 (N-terminal amino acids did not lead to major loss of activity, while peptides corresponding to the C-terminal part of PR-39 were hampered in their antimicrobial activity. However, shorter peptides were all much more sensitive to inhibition by salt. Active peptides induced ATP leakage and loss of membrane potential in Bacillus globigii and Escherichia coli, indicating a lytic mechanism of action for these peptides. Finally, only the mature peptide was able to induce IL-8 production in porcine macrophages, but some shorter peptides also had an effect on TNF-α production showing differential regulation of cytokine induction by PR-39 derived peptides. None of the active peptides showed high cytotoxicity highlighting the potential of these peptides for use as an alternative to antibiotics.

  20. The antimicrobial activities of the cinnamaldehyde adducts with amino acids.

    Science.gov (United States)

    Wei, Qing-Yi; Xiong, Jia-Jun; Jiang, Hong; Zhang, Chao; Wen Ye

    2011-11-01

    Cinnamaldehyde is a well-established natural antimicrobial compound. It is probable for cinnamaldehyde to react with amino acid forming Schiff base adduct in real food system. In this paper, 9 such kind of adducts were prepared by the direct reaction of amino acids with cinnamaldehyde at room temperature. Their antimicrobial activities against Bacillus subtilis, Escherichia coli and Saccharomyces cerevisiae were evaluated with benzoic acid as a reference. The adducts showed a dose-dependent activities against the three microbial strains. Both cinnamaldehyde and their adducts were more active against B. subtilis than on E. coli, and their antimicrobial activities were higher at lower pH. Both cinnamaldehyde and its adducts were more active than benzoic acid at the same conditions. The adduct compound A was non-toxic by primary oral acute toxicity study in mice. However, in situ effect of the adduct compound A against E. coli was a little lower than cinnamaldehyde in fish meat. This paper for the first time showed that the cinnamaldehyde adducts with amino acids had similar strong antimicrobial activities as cinnamaldehyde, which may provide alternatives to cinnamaldehyde in food to avoid the strong unacceptable odor of cinnamaldehyde.

  1. Antioxidant and antimicrobial activities of selected medicinal plants from Algeria

    Directory of Open Access Journals (Sweden)

    Krimat Soumia

    2014-06-01

    Full Text Available Objective: To evaluate the antioxidant and antimicrobial activity of methanolic extract extracts of selected Algerian medicinal plants. Methods: Antioxidant activity of extracts was evaluated in terms of radical scavenging potential (2,2-diphenyl-1-picrylhydrazyl and β-carotene bleaching assay. Total phenolic contents and flavonoid contents were also measured. Antimicrobial activity of these plants was examined against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Results: The values of IC50 ranged from 4.30 μg/mL to 486.6 μg/mL for the DPPH method, while total antioxidant activity using β-carotene/linoleic acid bleaching assay ranged from 17.03% to 86.13%. It was found that Pistacia lentiscus showed the highest antioxidant capacities using DPPH assay (IC50=4.30 μg/mL, while Populus trimula, Origanum glandulosum, Centaurea calcitrapa, Sysimbrium officinalis and Rhamnus alaternus showed the highest percent of total antioxidant activity in β-carotene/linoleic acid bleaching assay. Total phenolic and flavonoid contents ranged from 3.96 to 259.65 mg GAE/g extract and from 1.13 to 26.84 mg QE/g extract, respectively. The most interesting antimicrobial activity was obtained from Sysimbrium officinalis, Rhamnus alaternus, Origanum glandulosum, Cupressus sempervirens, Pinus halipensis and Centaurea calcitrapa. Conclusions: The results indicated that the plants tested may be potential sources for isolation of natural antioxidant and antimicrobial compounds.

  2. Antioxidant and antimicrobial activities of selected medicinal plants from Algeria

    Institute of Scientific and Technical Information of China (English)

    Krimat Soumia; Dob Tahar; Lamari Lynda; Boumeridja Saida; Chelghoum Chabane; Metidji Hafidha

    2014-01-01

    Objective:To evaluate the antioxidant and antimicrobial activity of methanolic extract extracts of selected Algerian medicinal plants. Methods:Antioxidant activity of extracts was evaluated in terms of radical scavenging potential (2,2-diphenyl-1-picrylhydrazyl) and β-carotene bleaching assay. Total phenolic contents and flavonoid contents were also measured. Antimicrobial activity of these plants was examined against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Results:The values of IC50 ranged from 4.30 μg/mL to 486.6 μg/mL for the DPPH method, while total antioxidant activity using β-carotene/linoleic acid bleaching assay ranged from 17.03%to 86.13%. It was found that Pistacia lentiscus showed the highest antioxidant capacities using DPPH assay (IC50=4.30 μg/mL), while Populus trimula, Origanum glandulosum, Centaurea calcitrapa, Sysimbrium officinalis and Rhamnus alaternus showed the highest percent of total antioxidant activity inβ-carotene/linoleic acid bleaching assay. Total phenolic and flavonoid contents ranged from 3.96 to 259.65 mg GAE/g extract and from 1.13 to 26.84 mg QE/g extract, respectively. The most interesting antimicrobial activity was obtained from Sysimbrium officinalis, Rhamnus alaternus, Origanum glandulosum, Cupressus sempervirens, Pinus halipensis and Centaurea calcitrapa. Conclusions:The results indicated that the plants tested may be potential sources for isolation of natural antioxidant and antimicrobial compounds.

  3. Antimicrobial and antioxidant activity of natural honeys of different origin

    Directory of Open Access Journals (Sweden)

    Miartina Fikselová

    2014-11-01

    Full Text Available To examine the antimicrobial and antioxidant activity of 15 natural honeys, honey samples were collected from different locations of Slovakia, Poland and Serbia. For antimicrobial activity determination honey solutions were prepared at three concentrations: 50, 25 and 12.5 % (by mass per volume. The potential antimicrobial activity of  selected samples against four species of bacteria (Escherichia coli CCM 3988, Pseudomonas aeroginosa CCM 1960, Staphylococcus epidermis CCM 4418, Bacillus cereus CCM 2010 and two species of yeasts (Saccharomyces cerevisiae CCM 8191, Candida albicans CCM 8216 was studied using the disc diffusion method. After incubation, the zones of inhibition of the growth of the microorganisms around the disks were measured. The strongest antimicrobial activity was shown at honey samples of 50 % concentration against Escherichia coli, Pseudomonas aeroginosa and Staphylococcus epidermis. Against Saccharomyces cerevisae and Candida albicans very low (at 50 %, 25 % concentration or zero antifugal (at 12.5 % concentration activity was determined. From the results obtained it was shown the variable ability of honey samples to scavenge stable free radical DPPH. TEACDPPH values ranged between 0.1-1.0 mmol.kg-1. As the antioxidative best source buckwheat honey was manifested and the lowest antioxidant activity was shown at acacia honey.

  4. Self-assembly of cationic multidomain peptide hydrogels: supramolecular nanostructure and rheological properties dictate antimicrobial activity

    Science.gov (United States)

    Jiang, Linhai; Xu, Dawei; Sellati, Timothy J.; Dong, He

    2015-11-01

    Hydrogels are an important class of biomaterials that have been widely utilized for a variety of biomedical/medical applications. The biological performance of hydrogels, particularly those used as wound dressing could be greatly advanced if imbued with inherent antimicrobial activity capable of staving off colonization of the wound site by opportunistic bacterial pathogens. Possessing such antimicrobial properties would also protect the hydrogel itself from being adversely affected by microbial attachment to its surface. We have previously demonstrated the broad-spectrum antimicrobial activity of supramolecular assemblies of cationic multi-domain peptides (MDPs) in solution. Here, we extend the 1-D soluble supramolecular assembly to 3-D hydrogels to investigate the effect of the supramolecular nanostructure and its rheological properties on the antimicrobial activity of self-assembled hydrogels. Among designed MDPs, the bactericidal activity of peptide hydrogels was found to follow an opposite trend to that in solution. Improved antimicrobial activity of self-assembled peptide hydrogels is dictated by the combined effect of supramolecular surface chemistry and storage modulus of the bulk materials, rather than the ability of individual peptides/peptide assemblies to penetrate bacterial cell membrane as observed in solution. The structure-property-activity relationship developed through this study will provide important guidelines for designing biocompatible peptide hydrogels with built-in antimicrobial activity for various biomedical applications.Hydrogels are an important class of biomaterials that have been widely utilized for a variety of biomedical/medical applications. The biological performance of hydrogels, particularly those used as wound dressing could be greatly advanced if imbued with inherent antimicrobial activity capable of staving off colonization of the wound site by opportunistic bacterial pathogens. Possessing such antimicrobial properties would

  5. Synthesis and antimicrobial activity of amphiphilic carbohydrate derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Roberta C.N.; Oda, Simone C.; Almeida, Mauro V. de; Le Hyaric, Mireille [Universidade Federal de Juiz de Fora (UFJF), MG (Brazil). Dept. de Quimica]. E-mail: mireille.hyaric@ufjf.edu.br; Lourenco, Maria C.S.; Vicente, Felipe R.C. [Fundacao Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil ). Instituto de Pesquisa Clinica Evandro Chagas (IPEC); Barbosa, Nadia R.; Trevizani, Rafael; Santos, Priscila L.C. [Universidade Federal de Juiz de Fora (UFJF), MG (Brazil). Faculdade de Farmacia e Bioquimica

    2008-07-01

    N-monoalkylated diamines were synthesised and treated with D-ribonolactone or D-gluconolactone. The resulting aldonamides were evaluated for their antimicrobial activity against S. aureus, E. coli, M. tuberculosis and C. albicans. Two hydrazides were also prepared from ribonohydrazide and their biological activity was compared to their amide analogues. All the ribono-derivatives displayed moderated antitubercular activity, and some of them were also active against S. aureus. (author)

  6. PHYTOCHEMICAL EVALUATION AND ANTIMICROBIAL ACTIVITY OF ETHANOLIC EXTRACT OF VISMIA GUIANENSIS (AUBL. CHOISY

    Directory of Open Access Journals (Sweden)

    Jose Otavio Carrera Silva Junior et al.

    2011-12-01

    Full Text Available Studies have been demonstrating that Vismia guianensis (Aubl. Choisy, popularly known as seal, a species native to South America has high anticancer and antimicrobial potential. The objective of this study was to evaluate the antimicrobial activity of the ethanolic extract obtained from the leaves of V. guianensis, and trace its chemical profile. The phytochemical screening showed the presence of different phenolic compounds in the extract. The high performance liquid chromatography performed on the sub-fractions A and B from the ethyl acetate fraction traced the chemical composition profile of the ethanol extract, composed by benzophenone, xanthones and anthraquinones. The antimicrobial activity of the extract evaluated by agar diffusion method showed inhibition against Gram-positive bacteria: Streptococcus mitis (ATCC 903, Streptococcus sanguis (ATCC 10557 and Staphylococcus aureus (ATCC 6538 and the fungi: Candida albicans (ATCC 40175, Candida krusei (ATCC 40147 and Candida parapsilosis (ATCC 40038.

  7. Antimicrobial Activity of Bacteriocins and Their Applications

    Science.gov (United States)

    Drosinos, Eleftherios H.; Mataragas, Marios; Paramithiotis, Spiros

    Bacteriocins are peptides or proteins that exert an antimicrobial action against a range of microorganisms. Their production can be related to the antagonism within a certain ecological niche, as the producer strain, being itself immune to its action, generally gains a competitive advantage. Many Gram-positive and Gram-negative microorganisms have been found to produce bacteriocins. The former, and especially the ones produced by lactic acid bacteria, has been the field of intensive research during the last decades mainly due to their properties that account for their suitability in food preservation and the benefits arising from that, and secondarily due to the broader inhibitory spectrum compared to the ones produced by Gramnegative microorganisms.

  8. Design of embedded-hybrid antimicrobial peptides with enhanced cell selectivity and anti-biofilm activity.

    Directory of Open Access Journals (Sweden)

    Wei Xu

    Full Text Available Antimicrobial peptides have attracted considerable attention because of their broad-spectrum antimicrobial activity and their low prognostic to induce antibiotic resistance which is the most common source of failure in bacterial infection treatment along with biofilms. The method to design hybrid peptide integrating different functional domains of peptides has many advantages. In this study, we designed an embedded-hybrid peptide R-FV-I16 by replacing a functional defective sequence RR7 with the anti-biofilm sequence FV7 embedded in the middle position of peptide RI16. The results demonstrated that the synthetic hybrid the peptide R-FV-I16 had potent antimicrobial activity over a wide range of Gram-negative and Gram-positive bacteria, as well as anti-biofilm activity. More importantly, R-FV-I16 showed lower hemolytic activity and cytotoxicity. Fluorescent assays demonstrated that R-FV-I16 depolarized the outer and the inner bacterial membranes, while scanning electron microscopy and transmission electron microscopy further indicated that this peptide killed bacterial cells by disrupting the cell membrane, thereby damaging membrane integrity. Results from SEM also provided evidence that R-FV-I16 inherited anti-biofilm activity from the functional peptide sequence FV7. Embedded-hybrid peptides could provide a new pattern for combining different functional domains and showing an effective avenue to screen for novel antimicrobial agents.

  9. Phytochemical, antimicrobial, and antioxidant activities of different citrus juice concentrates.

    Science.gov (United States)

    Oikeh, Ehigbai I; Omoregie, Ehimwenma S; Oviasogie, Faith E; Oriakhi, Kelly

    2016-01-01

    The search for new antimicrobial compounds is ongoing. Its importance cannot be overemphasized in an era of emerging resistant pathogenic organisms. This study therefore investigated the phytochemical composition and antioxidant and antimicrobial activities of different citrus juice concentrates. Fruit juices of Citrus tangerine (tangerine), Citrus paradisi (grape), Citrus limon (lemon), and Citrus aurantifolia (lime) were evaluated. Antimicrobial activities against five bacterial and three fungal strains were evaluated. The results revealed the presence of alkaloids, flavonoids, steroids, terpenoids, saponins, cardiac glycosides, and reducing sugars in all the juice concentrates. DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging capacities varied with tangerine and grape juices having better scavenging capacities than lemon and lime juices. Grape juice was observed to have a significantly higher (P < 0.05) ferric-reducing antioxidant potential (FRAP) value (364.2 ± 10.25 μmol/L Fe(II)/g of the extract) than the reference antioxidant, ascorbic acid (312.88 ± 5.61 μmol/L). Antimicrobial studies revealed differential antimicrobial activities against different microbial strains. Zones of inhibition ranging from 4 to 26 mm were observed for the antibacterial tests with 0-24 mm for antifungal test. Minimum inhibitory concentrations (MIC) and minimum bacteriostatic concentrations (MBC) for concentrates against bacterial strains ranged from 12.5 to 200 μg/mL. Lemon and lime juice concentrates had lower MIC and MBC values with orange and tangerine having the highest values. Minimum fungicidal concentrations ranged from 50 to 200 μg/mL. The results of this study suggest that these juice concentrates may have beneficial antimicrobial roles that can be exploited in controlling unwanted microbial growth.

  10. Evaluation of Membrane Stabilizing Activity, Total Phenolic Content, Brine Shrimp Lethality Bioassay, Thrombolytic and Antimicrobial Activities of Tagetes patula L.

    Directory of Open Access Journals (Sweden)

    Md. Ruhul Kuddus

    2012-11-01

    Full Text Available The methanol extract of leaf of Tagetes patula L. as well as its n-hexane, carbon tetrachloride, chloroform and aqueous soluble partitionates were subjected to screening for total phenolic content, brine shrimp lethality, membrane stabilizing, thrombolytic and antimicrobial activity. The membrane stabilizing activity was assessed by hypotonic solution-and heat-induced methods and was compared with acetyl salicylic acid. In the present studies, the n-hexane soluble fraction demonstrated strong membrane stabilizing activity in both hypotonic solution-and heat-induced methods with 44.48% and 42.68% inhibition of haemolysis, respectively. The total phenolic content was also determined and expressed in gallic acid equivalent. In brine shrimp bioassay, the crude methanol extract of leaf showed strong cytotoxic activity with LC50 value of 8.58 μg/ml compared to that of 0.451 μg/ml exhibited by standard vincristine sulphate. During assay for thrombolytic activity, the n-hexane soluble fraction revealed 43.7% lysis of clot while standard streptokinase and water, used as positive and negative controls, demonstrated 65.8% and 3.62% lysis of clot, respectively. In antimicrobial assay by disc diffusion method, all the samples exhibited moderate to significant antimicrobial activity (zone of inhibition = 9.0-22.0 mm against all the test organisms. Among all the samples, the carbon tetrachloride soluble fraction displayed strong antimicrobial activity against Escherichia coli (22.0 mm.

  11. Measurement of antimicrobial activity of isolated bacteria from the Caspian sea and molecular identification of strains with antimicrobial effect

    Directory of Open Access Journals (Sweden)

    Sajad Harounabadi

    2015-12-01

    Full Text Available Introduction: Easy access and wide use of antimicrobial compounds led to the emergence of resistance among microorganisms. Therefore, screening and identifying antimicrobial compound with high effect of microorganisms in different environments is necessary and vital . Using microorganisms for biological aims change them to an important tool to control pathogens. Streptomyces griseus is one of them. The aim of this study is isolation of marine bacteria with antimicrobial effect against gram positive and negative bacteria. Finally, molecular identification of strains with antimicrobial activity. Materials and methods: In this study, 162 strains were isolated from the Caspian Sea .The strains were cultured on special medium and finally antimicrobial activity on references strains as measured. Among them four strains with remarkable antimicrobial activity were identified and selected. The strains were subjected to 16S rDNA PCR sequencing. The strains were submitted to NCBI as new Streptomyces griseus strains. Results: Among 162 strains, 4 strains had the most antimicrobial activity. The result showed, the strains were the most effective on Bacillus subtilis and Staphylococcus aureus (Gram positive bacteria and the least effect were observed on Escherichia coli and Pseudomonas aeruginosa (Gram negative bacteria. After sequencing, the strains were classified to sterptomyces griseus genu. Discussion and conclusion: In this study, 4 strains with antimicrobial activity were identified. According to the strength of these bacteria for controlling pathogenic bacteria resistant to antibiotic, we can have more pure microorganisms in optimized and controlled conditions for using in pharmaceutical industries and also for the treatment of dangerous pathogenic bacteria.

  12. Coatings and surface modifications imparting antimicrobial activity to orthopedic implants.

    Science.gov (United States)

    Kargupta, Roli; Bok, Sangho; Darr, Charles M; Crist, Brett D; Gangopadhyay, Keshab; Gangopadhyay, Shubhra; Sengupta, Shramik

    2014-01-01

    Bacterial colonization and biofilm formation on an orthopedic implant surface is one of the worst possible outcomes of orthopedic intervention in terms of both patient prognosis and healthcare costs. Making the problem even more vexing is the fact that infections are often caused by events beyond the control of the operating surgeon and may manifest weeks to months after the initial surgery. Herein, we review the costs and consequences of implant infection as well as the methods of prevention and management. In particular, we focus on coatings and other forms of implant surface modification in a manner that imparts some antimicrobial benefit to the implant device. Such coatings can be classified generally based on their mode of action: surface adhesion prevention, bactericidal, antimicrobial-eluting, osseointegration promotion, and combinations of the above. Despite several advances in the efficacy of these antimicrobial methods, a remaining major challenge is ensuring retention of the antimicrobial activity over a period of months to years postoperation, an issue that has so far been inadequately addressed. Finally, we provide an overview of additional figures of merit that will determine whether a given antimicrobial surface modification warrants adoption for clinical use.

  13. Antimicrobial activity of kombucha made from Rtanj tea

    Directory of Open Access Journals (Sweden)

    Cvetković Dragoljub D.

    2005-01-01

    Full Text Available Kombucha is a beverage with special therapeutic properties produced by the metabolic activity of yeasts and acetic acid bacteria in sweetened black tea (traditional cultivation medium. The antimicrobial activity of kombucha (for consumption made from black tea and Rtanj tea, as well as particular control samples, was examined by the modified disc diffusion method. Salmonella enteritidis, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa Staphylococcus aureus, Bacillus sp., Sarcina lutea, Penicillium aurantiogriseum, Aspergilus niger, Aspergilus flavus, Rhodotorula sp. Candida pseudotropi-calis and Saccharomyces cerevisae have been used as test organisms. Acetic acid and kombucha samples show significant antimicrobial activity against all bacteria except Sarcina lutea. The other control samples (neutralized kombucha, tea and a "model sistem" show less bacteriostatic activity. Kombucha and acetic acid solution show borderline inhibitory activity against some moulds, while was no activity against yeasts.

  14. Antimicrobial activity of some endemic plant species from Turkey

    African Journals Online (AJOL)

    SERVER

    2007-08-06

    Aug 6, 2007 ... For the determination of antimicrobial activity, 3 g of ground plant parts were ... negative control, 1 ml of methanol – 5 ml of deionized water mixture ..... CAM. 2: 259-263. Dülger B, Ceyhan M, Alitsaous M, Uğurlu E (1999).

  15. Syntheses, Protonation Constants and Antimicrobial Activity of 2 ...

    African Journals Online (AJOL)

    NICO

    investigated for their effect on the antimicrobial activity.2,4 In this ... R.S. Walmsley, I.Z. Gundhla, T.A. Walmsley, T.I. Jauka, J. Dames, R.B. Walker, N. Torto and Z.R. Tshentu, ...... test compounds (2.5 mg mL–1) were serially diluted in 96 well.

  16. Synthesis and antimicrobial activities of some sulphur containing chromene derivatives.

    Science.gov (United States)

    Serbetçi, Tuba; Birteksöz, Seher; Prado, Soizic; Michel, Sylvie; Tillequin, François

    2012-07-01

    A series of 3,3-dimethyl-3Hbenzothieno[3,2-f][1]-benzopyran analogues modified at the pyran 1,2-double bond were synthesized. The corresponding dihydro and (+/-)-cis-diol derivatives were converted into diacetate and cyclic carbonate upon acylation. The title compounds were characterized by spectroscopic analysis and screened for their antimicrobial activity in vitro.

  17. Antimicrobial and Antifungal Activity of Pelargonium roseum Essential Oils

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    Gâlea Carmen

    2014-12-01

    Conclusion: The volatile oils exhibited considerable inhibitory effects against all the organisms under test, in some cases comparable with those of the reference antibiotics. There were no considerable differences between the antimicrobial activities of the oil obtained by distillation and commercially available Pelargonium oils.

  18. Antimicrobial activity of seed, pomace and leaf extracts of sea ...

    African Journals Online (AJOL)

    Antimicrobial activity of seed, pomace and leaf extracts of sea buckthorn ( Hippophae rhamnoides L.) against foodborne and food spoilage pathogens. ... Bacterial enumeration was significantly reduced by 0.15 to 0.31, 0.26 to 1.72 and 0.59 to ...

  19. Synthesis and Antimicrobial Activities of Some Pyrazoline Derivatives

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    Ganguly Sushmita S

    2012-10-01

    Full Text Available An efficient synthesis of 3, 5-disubstituted-2-pyrazoline was carried out by the condensation of chalcones with hydrazine hydrate in ethanol in presence of piperidine. The newly synthesized compounds were characterized by 1H NMR spectroscopy, IR spectroscopy, MS, elemental analysis and screened for their antimicrobial activity against various strains of bacteria and fungi.

  20. Antimicrobial Activity of the Lichen Cetraria islandica (L.) Ach.

    OpenAIRE

    Başaran DÜLGER; GÜCİN, Fahrettin

    1998-01-01

    In this study, extracts of Cetraria islandica (L.) Ach. were prepared with Ethyl acetate, Acetone, Chloroform and Ethanol and antimicrobial activities of these extracts were examined on test microorganisms as follows: Escherichia coli ATCC 11230, Enterobacter aerogenes CCM 2531, Staphylococcus aureus 6538P, Staphylococcus epidermidis, Bacillus subtilis La2114, Bacillus cereus var. mycoides, Bacillus sphaericus, Bacillus thurigiensis, Bacillus megaterium, Mycobacterium smegmatis RUT, Salmo...

  1. In vitro antimicrobial activity of mangrove plant Sonneratia alba

    Institute of Scientific and Technical Information of China (English)

    Shahbudin Saad; Muhammad Taher; Deny Susanti; Haitham Qaralleh; Anis Fadhlina Izyani Bt Awang

    2012-01-01

    Objective:To investigate the antimicrobial property of mangrove plant Sonneratia alba (S. alba). Methods: The antimicrobial activity was evaluated using disc diffusion and microdilution methods against six microorganisms. Soxhlet apparatus was used for extraction with a series of solvents, n-hexane, ethyl acetate and methanol in sequence of increasing polarity. Results:Methanol extract appeared to be the most effective extract while n-hexane extract showed no activity. The antimicrobial activities were observed against the gram positive bacteria Staphylococcus aureus (S. aureus) and Bacillus cereus (B. cereus), the gram negative Escherichia coli (E. coli) and the yeast Cryptococcus neoformans. Pseudomonas aeruginosa and Candida albicans appeared to be not sensitive to the concentrations tested since no inhibition zone was observed. E. coli (17.5 mm) appeared to be the most sensitive strain followed by S. aureus (12.5 mm) and B. cereus (12.5 mm). Conclusions:From this study, it can be concluded that S. alba exhibits antimicrobial activities against certain microorganisms.

  2. Phenolic Content, and Antioxidant and Antimicrobial Activities of ...

    African Journals Online (AJOL)

    Erah

    Antimicrobial activity was evaluated by measuring the zone of inhibition against selected test .... and acetate buffer (pH 4.5) were also purchased ... oxonium form predominates at pH 1.0, and ..... extraction of grape skin polyphenols improves.

  3. Antimicrobial Activity of Calcium Hydroxide in Endodontics: A Review

    Science.gov (United States)

    Shalavi, S; Yazdizadeh, M

    2012-01-01

    The purpose of endodontic therapy is to preserve the patient's natural teeth without compromising the patient's local or systemic health. Calcium hydroxide has been included in several materials and antimicrobial formulations that are used in several treatment modalities in endodontics, such as inter-appointment intracanal medicaments. The purpose of this article was to review the antimicrobial properties of calcium hydroxide in endodontics. Calcium hydroxide has a high pH (approximately 12.5-12.8) and is classified chemically as a strong base. The lethal effects of calcium hydroxide on bacterial cells are probably due to protein denaturation and damage to DNA and cytoplasmic membranes. Calcium hydroxide has a wide range of antimicrobial activity against common endodontic pathogens but is less effective against Enterococcus faecalis and Candida albicans. Calcium hydroxide is also a valuable anti-endotoxin agent. However, its effect on microbial biofilms is controversial. PMID:23323217

  4. Antimicrobial activity of nanocomposite zirconium nitride/silver coatings to combat external bone fixation pin infections.

    Science.gov (United States)

    Wickens, David J; West, Glen; Kelly, Peter J; Verran, Joanna; Lynch, Stephen; Whitehead, Kathryn A

    2012-10-01

    During external fixation, temporary implants are used to penetrate the skin, muscle and bone to support severely fractured bones. This creates a biologically critical interface at the site of entry, which potentially allows a risk of infection. The aim of this study, therefore, was to investigate potential antimicrobial nanocomposites to combat infection. Magnetron sputtering was used to produce zirconium nitride/silver nanocomposite coatings, which were prepared at two different silver concentrations of 15.5 at.% and 29.8 at.%. These coatings were characterized for morphology, chemical composition, and antimicrobial activity in comparison to pure zirconium nitride and stainless steel. Staphylococcus aureus and Staphylococcus epidermidis were used as in vitro test organisms in a range of antimicrobial assays; retention of the bacteria on the surfaces and their survival using LiveDead™ staining; the use of a metabolic redox dye to indicate a contact kill and zone of inhibition assays to indicate leaching of inhibitory silver ions. Antimicrobial tests demonstrated a significant kill when the bacterial cells came in contact with the coatings containing silver at both 15.5 at.% and 29.8 at.%. No inhibitory leaching from the surfaces occurred. These surfaces demonstrate potential for use as antimicrobial fixation pin coatings.

  5. Antimicrobial activity and phytochemical screening 4 of Arbutus unedo L

    OpenAIRE

    Dib, Mohamed El Amine; Allali, Hocine; Bendiabdellah, Amel; Meliani, Nawel; Tabti, Boufeldja

    2012-01-01

    In this study, antimicrobial activities of water and methanol extract, and three phenolic fractions of the roots of Arbutus unedo L. were investigated. Poor antibacterial activity against both Staphylococcus aureus and Pseudomonas aeruginosa bacteria was shown with water and methanol extract. However moderate antibacterial activity was shown by water extract and phenolic fractions against Escherichia coli and S. aureus, respectively. The phytochemical screening of roots of A. u...

  6. ANTIMICROBIAL ACTIVITIES OF RICINUS COMMUNIS AGAINST SOME HUMAN PATHOGENS

    OpenAIRE

    Kushwah Poonam; Singh Krishan Pratap

    2012-01-01

    The present paper deals with the antimicrobial activities of seed extracts of Ricinus communis against some human pathogenic bacteria namely Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Escherichia coli and two fungal strains namely Candida albicans and Candida glabrata. The aqueous and methanol extracts of seeds were screened for their antibacterial activity using agar disc diffusion method. The aqueous seed extracts were less active but methanol extracts showed high degree zon...

  7. Phytochemical investigation and evaluation of anti-microbial and anti-oxidant activity of Foeniculum vulgare (fennel

    Directory of Open Access Journals (Sweden)

    Shabana Bano

    2016-07-01

    Full Text Available In this study, methanol extract of fennel seeds was examined for its antioxidant and antimicrobial activities. Phytochemical constituents of the fennel extract were also analysed, that revealed the presence of flavonoids, terpenoids and glycosides. Total phenol content of the extract was determined by using Folin-Ciocalteu reagent and was found to be 3.48 ± 4.2 (mg GAE/g DM. The antimicrobial activity of fennel extract was evaluated against following microorganisms: Escherichia coli, Bacillus pumilus, Staphylococcus aureus, Listeria monocytogenes and Enteropathogenic E. coli (EPEC. Maximum antimicrobial activity of the fennel extract was found against Staphylococcus aureus, showing an inhibition zone of 20.00 mm. DPPH radical scavenging assay was used to evaluate the antioxidant activity of the fennel extract and its IC50 value was also calculated. Thus, the results of the present investigation demonstrate antimicrobial and antioxidant activities of fennel extract and also the presence of various phytochemicals.

  8. Evaluation of antimicrobial activity of ethanolic extract of Dactyloctenium aegyptium

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    Veeresh Kumar P

    2015-12-01

    Full Text Available Dactyloctenium aegyptium is an Indian medicinal plant to provide fuel, fodder and stabilizes soil in natural woodland and plantations. Dactyloctenium aegyptium is known for its antimicrobial activity, but the antifungal effects of Ethanolic extract on growth of Aspergillus niger have been observed. The extract showed a favorable antifungal activity against Aspergillus niger. Ethanolic extract of  Dactyloctenium aegyptium were examined for their phytochemical compounds and antimicrobial potential against three standard bacteria(Escherichia coli,Klebsiella Pneumonia,Staphylococci, and one standard fungus (Aspergillus niger.The phytochemical analysis showed the presence of some active principle which correlates with the antifungal activity of ethanolic extract of Dactyloctenium aegyptium. The ethanolic extract of Dactyloctenium aegyptium shows the maximum antifungal activity compared to Griseoflavin.

  9. Antioxidant, Antigenotoxic, Antimicrobial Activities and Phytochemical Analysis of Dianthus carmelitarum

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    Rezzan Aliyazicioglu

    2017-05-01

    Full Text Available In this study, we investigated the phytochemical composition, antioxidant, antimicrobial, and antigenotoxic properties of the aqueous extract of Dianthus carmelitarum for the first time. The phenolic and volatile compounds, antioxidant, antimicrobial and antigenotoxic activities of the extract were determined by HPLC and SPME-GC-FID/MS, spectrophotometric, agar well diffusion methods and comet assay, respectively. The polyphenolic content and ferric reducing power values of the extract were found 12.6 ± 0.27 mg gallic acid and 238 ± 2.89 μM trolox equivalents per g sample, respectively. Syringaldehyde and chlorogenic acid were detected as major phenolic compounds, while terpenes were determined as major volatile compound. Dianthus carmelitarum extract especially exhibited moderate antimicrobial activity against Mycobacterium smegmatis. Extract reduced H 2O 2-induced DNA damage in a concentration dependent manner in fibroblast cells compared to positive control (only 20 μM H 2O 2 treatment. Dianthus carmelitarum can be considered in the food, cosmetic, and drug industries due to its antioxidant, antimicrobial, and antigenotoxic activities.

  10. SCREENING OF PLANT EXTRACTS FOR ANTIMICROBIAL ACTIVITY AGAINST BACTERIA

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    Alexander Vatľák

    2014-02-01

    Full Text Available The aim of this study was antimicrobial action of the methanolic extracts of Equisetum arvense L. and Urtica dioica L. against gramnegative and grampositive bacteria. The antimicrobial activities of the extracts against gramnegative bacteria: Escherichia coli CCM 3988, Listeria ivanovii CCM 5884, Listeria innocua CCM 4030, Pseudomonas aeruginosa CCM 1960, Serratia rubidaea CCM 4684 and grampositive bacteria: Brochothrix thermosphacta CCM 4769, Enterococcus raffinosus CCM 4216, Lactobacillus rhamnosus CCM 1828, Paenobacillus larvae CCM 4483 and Staphylococcus epidermis CCM 4418 were determined by the disc diffusion method and the microbroth dilution method according to CLSI. Probit analysis was used in this experiment. Of the 2 plant extracts tested, all extracts showed antimicrobial activity against one or more species of microorganisms. The most antimicrobial activity showed methanolic plant extract of E. arvense against S. epidermis with disc diffusion method and with microbroth dilution method against S. rubidaea and plant extract Urtica dioica with disc diffusion method against P. aeruginosa and with microbroth dilution method against S. rubidaea and E. coli.

  11. Antimicrobial activity of different endodontic sealers: An in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Saha S

    2010-01-01

    Full Text Available Background: Microbes are considered as the primary etiological agents in endodontic diseases. The ways of reducing these agents are root canal debridement, antimicrobial irrigants, and antibacterial filling materials. But the complexity of the pulp canal system presents a problem for chemomechanical preparation. One of the factors determining the success of endodontic treatment is the sealing material with a potent bactericidal effect. Aim: The aim of the present study was to assess the antimicrobial activity of endodontic sealers of different bases - in vitro. Materials and Method: The antimicrobial activity of three root canal sealers (endomethasone, AH 26, and apexit was evaluated against seven strains of bacteria at various time intervals using the agar diffusion test. The freshly mixed sealers were placed in prepared wells of agar plates inoculated with the test microorganisms. The plates were incubated for 24, 48, 72 hours, and 7 and 15 days. The mean zones of inhibition were measured. Statistical Analysis: All statistical analysis was performed using the SPSS 13 statistical software version. The analysis of variance (ANOVA, post-hoc Bonferroni test, and paired t test were performed to reveal the statistical significance. Results: Statistically significant zones of bacterial growth inhibition were observed in descending order of antimicrobial activity: endomethasone, AH 26, and apexit. Conclusion: Zinc oxide eugenol based root canal sealer produced largest inhibitory zones followed in decreasing order by epoxy resin based sealer and least by calcium hydroxide based root canal sealer.

  12. Antimicrobial activity of hydroalcoholic extracts from genipap, baru and taruma

    Directory of Open Access Journals (Sweden)

    Fabíola Brandão dos Santos

    Full Text Available ABSTRACT: Microbial resistance is a serious public health problem, which has led to the search for alternative treatments to replace antibiotics, including studies to evaluate the antimicrobial potential of species in Brazil’s Cerrado. Therefore, the present study aimed to evaluate the antimicrobial activity of hydroalcoholic extracts of genipap, baru, and taruma against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans using disc diffusion tests and microdilution. Results indicated that all genipap extracts showed inhibition zones and minimum inhibitory concentrations (MICs and minimum microbicidal concentrations (MMCs ranging between 150μg/mL and 940μg/mL against all microorganisms tested. Baru pulp extracts exhibited larger inhibition zones against S. aureus and MIC and MMC results between 150µg/mL and 1000µg/mL against all microorganisms except P. aeruginosa. The taruma 30% pulp and seed extracts exhibited the largest halos against S. aureus and MIC and MMC results were between 150μg/mL and 1000μg/mL against all microorganisms except C. albicans. All fruits displayed potential for antimicrobial activity, particularly the genipap’s pulp extracts. Further studies should be performed to identify compounds with antimicrobial activity and to test their applicability as preservatives in foods, as alternatives to antibiotic growth promoters, and as sanitizing agents.

  13. Antimicrobial activity of clinically used antiseptics and wound irrigating agents in combination with wound dressings.

    Science.gov (United States)

    Hirsch, Tobias; Limoochi-Deli, Simin; Lahmer, Armin; Jacobsen, Frank; Goertz, Ole; Steinau, Hans-Ulrich; Seipp, Hans-Martin; Steinstraesser, Lars

    2011-04-01

    A primary strategy for preventing and treating wound infection in chronic wounds is the use of topical antiseptics and wound irrigating agents. However, their interaction with commonly used wound dressings has not yet been investigated. In this study, the authors analyzed the antimicrobial activity of antiseptics and wound irrigating agents used with commercially available wound dressings. Five clinically used antiseptics and wound irrigating agents (Prontosan, Lavasept, Braunol, Octenisept, and Betaisodona) were tested in the presence or absence of 42 wound dressings against Staphylococcus aureus. The determination of antibacterial activity was performed by disk diffusion assay. Povidone-iodine-based products showed sufficient antimicrobial activity in 64 to 78 percent of the combinations assessed (p > 0.01). The octenidine derivate Octenisept showed sufficient antimicrobial activity in 54 percent of combinations. Polyhexamethylene biguanide derivatives demonstrated sufficient antimicrobial activity in 32 percent of the combinations. This study revealed that commonly used wound dressings dramatically reduce antibacterial activity of clinically used antiseptics and wound irrigating agents in vitro.

  14. An Undergraduate Laboratory Activity Demonstrating Bacteriophage Specificity

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    Mary E. Allen

    2013-02-01

    Full Text Available Bacteriophage are among the most diverse and numerous microbes inhabiting our planet. Yet many laboratory activities fail to engage students in meaningful exploration of their diversity, unique characteristics, and abundance. In this curriculum activity students use a standard plaque assay to enumerate bacteriophage particles from a natural sample and use the scientific method to address questions about host specificity and diversity. A raw primary sewage sample is enriched for bacteriophage using hosts in the family Enterobacteriaceae. Students hypothesize about host specificity and use quantitative data (serial dilution and plaque assay to test their hypotheses. Combined class data also help them answer questions about phage diversity. The exercise was field tested with a class of 47 students using pre- and posttests. For all learning outcomes posttest scores were higher than pretest scores at or below p = 0.01. Average individualized learning gain (G was also calculated for each learning outcome. Students’ use of scientific language in reference to bacteriophage and host interaction significantly improved (p = 0.002; G = 0.50. Improved means of expression helped students construct better hypotheses on phage host specificity (G = 0.31, p = 0.01 and to explain the plaque assay method (G = 0.33, p = 0.002. At the end of the exercise students also demonstrated improved knowledge and understanding of phage specificity as related to phage therapy in humans (p < 0.001; G = 51.

  15. COW DUNG- A BOON FOR ANTIMICROBIAL ACTIVITY

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    SUSHMITA SHRIVASTAVA*, ALKA MISHRA ARTI PAL

    2014-09-01

    Full Text Available India is an agricultural country having variety of plants and animals. Among the animals, cattle like cow has a prominent place in our country. It is considered as go-mata and worshipped by every hindu of India. The five products of cow called “Panchgavya” is a precious gift of this holy animal to our society, which consist of milk, curd, ghee, urine and dung. Among these, cow dung also called cow pad, is a component having crude protein, cellulose, hemicellulose and minerals. It is an efficient organic manure used to increase plant yield in fields. Cow dung slurry is also used by people of our country for plastering the floors and walls of their houses. Considering this custom of our society, a study had been done to evaluate antibacterial and antifungal properties of cow dung extract in distil water, ethanol and n- hexane against Candida, E. coli, Pseudomonas and Staphylococcus aureus and found it highly effective against these microbes. The study revealed that cow dung extract possess antimicrobial properties, which can be used to fight against certain pathogenic diseases and other ailments.

  16. Antimicrobial activity of topical skin pharmaceuticals - an in vitro study.

    Science.gov (United States)

    Alsterholm, Mikael; Karami, Nahid; Faergemann, Jan

    2010-05-01

    The aim of this study was to investigate the antimicrobial activity of currently available topical skin pharmaceuticals against Candida albicans, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus pyogenes. The agar dilution assay was used to determine the minimal inhibitory concentration for cream formulations and their active substances. Corticosteroid formulations with the antiseptics clioquinol or halquinol were active against all microbes. The hydrogen peroxide formulation was primarily active against staphylococci. Clotrimazole, miconazole and econazole showed an effect against staphylococci in addition to their effect on C. albicans. In contrast, terbinafine had no antibacterial effect. Fusidic acid was active against staphylococci, with slightly weaker activity against S. pyogenes and no activity against C. albicans or E. coli. In summary, some topical skin pharmaceuticals have broad antimicrobial activity in vitro, clioquinol and halquinol being the most diverse. In limited superficial skin infection topical treatment can be an alternative to systemic antibiotics and should be considered. With the global threat of multi-resistant bacteria there is a need for new, topical, non-resistance-promoting, antimicrobial preparations for the treatment of skin infections.

  17. Antimicrobial Activity of Lactoferrin-Related Peptides and Applications in Human and Veterinary Medicine

    Directory of Open Access Journals (Sweden)

    Natascia Bruni

    2016-06-01

    Full Text Available Antimicrobial peptides (AMPs represent a vast array of molecules produced by virtually all living organisms as natural barriers against infection. Among AMP sources, an interesting class regards the food-derived bioactive agents. The whey protein lactoferrin (Lf is an iron-binding glycoprotein that plays a significant role in the innate immune system, and is considered as an important host defense molecule. In search for novel antimicrobial agents, Lf offers a new source with potential pharmaceutical applications. The Lf-derived peptides Lf(1–11, lactoferricin (Lfcin and lactoferrampin exhibit interesting and more potent antimicrobial actions than intact protein. Particularly, Lfcin has demonstrated strong antibacterial, anti-fungal and antiparasitic activity with promising applications both in human and veterinary diseases (from ocular infections to osteo-articular, gastrointestinal and dermatological diseases.

  18. Phytochemical investigation and in vitro antimicrobial activity of Richardia scabra

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    Kathirvel Poonkodi

    2016-06-01

    Full Text Available The present study was aimed to evaluate the phytochemical screening and antimicrobial activity of the petroleum ether and methanol extracts from the mature leaves of Richardia scabra from India. Disc diffusion method was used to determine the zone inhibition of the tested samples for antibacterial and agar plug method was used to determine the antifungal activity, while the microtube-dilution technique was used to determine the minimum inhibitory concentration. Both extracts showed significant antibacterial and antifungal activities when tested against 10 bacterial and four fungal strains. The minimum inhibitory concentrations of the methanol extract of R. scabra ranged between 12.5–100 μg/mL for bacterial strains. Alkaloids, steroids, flavonoids, fatty acids, terpenoids and simple sugar were detected as phytoconstituents of extracts. To the best of our knowledge, this is the first report against antimicrobial activity of common weed species R. scabra found in India.

  19. Synthetic analogs of anoplin show improved antimicrobial activities

    DEFF Research Database (Denmark)

    Munk, Jens; Uggerhøj, Lars Erik; Poulsen, Tanja Juul;

    2013-01-01

    We present the antimicrobial and hemolytic activities of the decapeptide anoplin and 19 analogs thereof tested against methicillin-resistant Staphylococcus aureus ATCC 33591 (MRSA), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), vancomycin-resistant Enterococcus faecium (ATCC...... 700221) (VRE), and Candida albicans (ATCC 200955). The anoplin analogs contain substitutions in amino acid positions 2, 3, 5, 6, 8, 9, and 10. We use these peptides to study the effect of altering the charge and hydrophobicity of anoplin on activity against red blood cells and microorganisms. We find...... that increasing the charge and/or hydrophobicity improves antimicrobial activity and increases hemolytic activity. For each strain tested, we identify at least six anoplin analogs with an improved therapeutic index compared with anoplin, the only exception being Enterococcus faecium, against which only few...

  20. Antimicrobial activity of Iranian propolis and its chemical composition

    Directory of Open Access Journals (Sweden)

    Yaghoubi M.J.

    2007-04-01

    Full Text Available The objective of this study was to investigate the antimicrobial activity of ethanol extract of Iranian propolis on some microorganisms using disc diffusion method. The chemical composition of the propolis was also investigated using thin layer chromatography and spectrophotometric methods. Ethanol extract of propolis showed activity only against Gram-positives and fungi, whereas no activity was observed against Gram-negatives. Thin layer chromatography screening revealed the presence of pinocembrine, caffeic acid, kaempferol, phenethyl caffeate, chrysin, and galangin in Iranian propolis. The total flavonoid and phenolic contents were 7.3% and 36%, respectively, which suggests that the strong antimicrobial activity of Iranian propolis may be due to high levels of phenolic and flavonoid compounds.

  1. Repurposing the antihistamine terfenadine for antimicrobial activity against Staphylococcus aureus.

    Science.gov (United States)

    Perlmutter, Jessamyn I; Forbes, Lauren T; Krysan, Damian J; Ebsworth-Mojica, Katherine; Colquhoun, Jennifer M; Wang, Jenna L; Dunman, Paul M; Flaherty, Daniel P

    2014-10-23

    Staphylococcus aureus is a rapidly growing health threat in the U.S., with resistance to several commonly prescribed treatments. A high-throughput screen identified the antihistamine terfenadine to possess, previously unreported, antimicrobial activity against S. aureus and other Gram-positive bacteria. In an effort to repurpose this drug, structure-activity relationship studies yielded 84 terfenadine-based analogues with several modifications providing increased activity versus S. aureus and other bacterial pathogens, including Mycobacterium tuberculosis. Mechanism of action studies revealed these compounds to exert their antibacterial effects, at least in part, through inhibition of the bacterial type II topoisomerases. This scaffold suffers from hERG liabilities which were not remedied through this round of optimization; however, given the overall improvement in activity of the set, terfenadine-based analogues provide a novel structural class of antimicrobial compounds with potential for further characterization as part of the continuing process to meet the current need for new antibiotics.

  2. PHYTOCHEMICAL ANALYSIS AND ANTIMICROBIAL ACTIVITY OF CASIA OCCIDENTALIS (L

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    Venkanna Lunavath

    2013-02-01

    Full Text Available The trend of using natural products has increased and the active plant extracts are frequently screened for new drug discoveries. The present study deals with the screening of Casia occidentalis leaves for their antimicrobial activity against various strains of bacteria. Plant Cassia occidentalis belongs to family Caesalpiniaceae, is a diffuse offensively odorous under shrub. Casia occidentalis were shade dried, powered and was extracted using solvents Methanol. The antimicrobial activity test performed by the disc diffusion method. Preliminary phytochemical analysis of the plant extracts fractions of HXF, CTF, CFF and AQF showed the presence of carbohydrates, amino acids, phytosterols, fixed oils and phenolic compounds. The AQF fraction of C. occidentalis showed high activity across pseudomonas aeuruginosa and staphylococcus aureus bacteria. The present study indicates the potential usefulness of Casia occidentalis leaves in the treatment of various diseases caused by micro-organisms.

  3. Synthesis, Characterization and Antimicrobial Activity of New Thiadiazole Derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Mullick, Pooja; Khan, Suroor A.; Verma, Surajpal; Alam, Ozair [Hamdard University, New Delhi (India)

    2010-08-15

    A series of thiadiazole derivatives were synthesized with differently substituted benzoic acids which were cyclized to give differently substituted thiazolidin-4-one. Elemental analysis, IR, {sup 1}H NMR, {sup 13}C NMR and mass spectral data confirmed the structure of the newly synthesized compounds. The derivatives of these moieties were evaluated for antimicrobial activity. Most of the synthesized compounds showed good antimicrobial activity at 200 and 100 μg/mL. Compounds showed most significant antibacterial activity against gram negative test organism Escherichia coli and most significant antifungal activity against test organisms Aspergillus niger and Candida albicans. It was observed that compounds with OCH{sub 3} at 3, 4 position of phenyl ring [5(a-l)] were more potent against microbes as compared to compounds having unsubstituted phenyl ring [4(a-l)].

  4. Chemical composition and antimicrobial activity of hexane leaf extract of Anisopus mannii (Asclepiadaceae

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    Aliyu Muhammad Musa

    2015-06-01

    Full Text Available Objective: To determine the chemical constituents and antimicrobial activity of the hexane leaf extract of Anisopus mannii against a wide range of human pathogenic microorganisms. Methods: The chemical constituents of the hexane leaf extract was determined using gas chromatography-mass spectrometry (GC-MS analysis; and the antimicrobial activity was evaluated on clinical susceptible and resistant bacterial and fungal isolates using the disc diffusion and broth micro dilution methods. Results: GC-MS analysis of the hexane leaf extract revealed 32 compounds, representing 73.8% of the identified components. The major compounds were hexadecanoic acid, ethyl ester (34%, oxirane, hexadecyl- (11% and 9, 12, 15-octadecatrienoic acid, ethyl ester, (Z, Z, Z (9.6%. Results from the antimicrobial activity demonstrated higher inhibition zones against B. cereus (29 mm, followed by S. pyogenes (28 mm. Other notable inhibitions were observed with E. faecalis (27 mm, P. vulgaris (26 mm and MRSA (25 mm. The MIC values ranged from 0.625 mg/mL to 1.25 mg/mL while the MBC/MFC values ranged from 2.5 mg/mL to 5.0 mg/mL. Conclusion: These results support the traditional use of the plant and demonstrate the huge potential of A. mannii as a source of antimicrobial compounds. [J Intercult Ethnopharmacol 2015; 4(2.000: 129-133

  5. Antimicrobial and Antioxidant Activities of Hornstedtia leonurus Retz. Extracts

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    Nor Akmalazura Jani

    2016-01-01

    Full Text Available The n-hexane, ethyl acetate and methanol extracts of the rhizome, leaf and stem of Hornstedtia leonurus Retz. from Malaysia were tested for antimicrobial and antioxidant activities. Antimicrobial activities were screened against three bacteria and two fungi by the broth microdilution assay, while antioxidant activities were analysed using DPPH radical scavenging assay. Most of the extracts exhibited weak to moderate antimicrobial activities (MIC 900 – 1800 µg/mL except ethyl acetate extract of the rhizome with strong activity against Candida albicans (MIC 225 µg/mL and Aspergillus niger (MIC 450 µg/mL as well as methanol extract of the rhizome that inhibited activity of Staphylococcus aureus with MIC value of 450 µg/mL. Among nine extracts tested, n-hexane extract of the rhizome possessed moderate free radical scavenging activity with IC50 value of 59.60 ± 0.69 µg/mL compared to vitamin C (IC50 = 21.21 ± 1.25 µg/mL.

  6. Study of the nanomaterials and their antimicrobial activities

    Science.gov (United States)

    Ramadi, Muntaha

    In the last decade, the world faced huge problems associated with the spread of antimicrobial resistant infections that are essentially untreatable such as methicillin resistant Staphylococcus aureus (MRSA) infection. These infections have begun to occur in both hospital and community environments. Developing new antimicrobial surface coatings can hold a great promise to minimize and control various problems that associated with the spreading of infections and biofilms formation, these coatings can be used in medicine where medical devices associated with severe infections, in construction industry and the in food packaging industry. It has been established that single-walled CNTs exhibit a strong antimicrobial activity and can pierce bacterial cell walls. Recently, nanomaterial structures that made from pure carbon such as CNTs have been seen as promising candidates for many potential applications in Biotechnology and bioscience due to the combination of their extraordinary properties that arise from surface area, light weight, strength, flexibility, unique electrical conductivity and many more novel physical and chemical properties at nanoscale level. CNTs have been used widely in biomedical field including drug delivery, gene therapy and creating new biomedical devices with novel properties. Researchers have now made a first step to add carbon nanotubes to antimicrobial agents list. There are two types of CNTs have been used in biomedical research. The first one is a single-walled carbon nanotube (SWNT) and the second is a multi-walled carbon nanotube (MWNT). Recent in vitro studies suggest that carbon nanotubes have antimicrobial activity and coating CNTs with nickel nanoparticle could enhance the antimicrobial activity of cabon nanotubes. In order to test this hypothesis, nickel nanoparticles were deposited on carbon nanotubes (CNTs) by electrochemical deposition. The carbon nanotubes used in this study were XD-CNTs, SWNTs and Ni-coated CNTs. The structure and

  7. Antimicrobial activity of carvacrol: current progress and future prospectives.

    Science.gov (United States)

    Nostro, Antonia; Papalia, Teresa

    2012-04-01

    During the last few years the scientific community has shown a considerable interest in the study of plant materials as sources of new compounds to be processed into antimicrobial agents. In this context, carvacrol, a monoterpenic phenol, has emerged for its wide spectrum activity extended to food spoilage or pathogenic fungi, yeast and bacteria as well as human, animal and plant pathogenic microorganisms including drug-resistant and biofilm forming microorganisms. The antibacterial activity of carvacrol has been attributed to its considerable effects on the structural and functional properties of cytoplasmatic membrane. The data reported in this review provide an overview of the published literature regarding the antimicrobial properties of carvacrol and the recent patents claimed in order to highlight its future applications as a new antimicrobial agent. These could concern either the natural preservation in the cosmetic and food industries or an alternative which supports the conventional antimicrobial protocols. Interestingly, carvacrol alone or associated with one or more synergistic products could be incorporated in different formulations for biomedical and food packaging applications. However, more detailed safety investigations and in vivo studies should be carried out so that this molecule could be used in the future.

  8. Antioxidant and antimicrobial activity of lecithin free egg yolk protein preparation hydrolysates obtained with digestive enzymes

    Directory of Open Access Journals (Sweden)

    Aleksandra Zambrowicz

    2012-12-01

    Full Text Available ABSTRACT:Several biological activities have now been associated with egg protein- derived peptides, including antihypertensive, antimicrobial, immunomodulatory, anticancer and antioxidantactivities, highlighting the importance of these biopeptides in human health, and disease prevention and treatment. Special attention has been given to peptides with antioxidant and antimicrobial activities as a new source of natural preservatives in food industry. In this study, the antioxidant properties of the egg-yolk protein by-product (YP hydrolysates were evaluated based on their radical scavenging capacity (DPPH, Fe2+chelating effect and ferric reducing power (FRAP. Furthermore, antimicrobial properties of obtained hydrolysates against Bacillus species were studied. The degrees (DHs of hydrolysis for 4h hydrolysates were: 19.1%, 13.5% and 13.0%, for pepsin, chymotrypsin and trypsin, respectively. Pepsin was the most effective in producing the free amino groups (1410.3 μmolGly/g. The RP-HPLC profiles of the protein hydrolysates showed differences in the hydrophobicity of the generated peptides.Trypsin hydrolysate obtained after 4h reaction demonstrated the strongest DPPH free radical scavenging activity (0.85 µmol Troloxeq/mg. Trypsin and chymotrypsin hydrolysates obtained after 4h reaction exhibited 4 times higher ferric reducing capacity than those treated bypepsin. The hydrolysis products obtained from YP exhibited significant chelating activity. The 4h trypsin hydrolysate exhibited weak antimicrobial activity against B. subtilis B3; B. cereus B512; B. cereus B 3p and B. laterosporum B6.

  9. Antimicrobial activity of methanolic extracts of selected marine macroalgae against some pathogenic microorganisms

    Directory of Open Access Journals (Sweden)

    Ehab Omer Abdalla

    2016-05-01

    Full Text Available Objective: To evaluate the antimicrobial activity of methanolic extracts of six marine macroalgae belonging to green algae (Chlorophyceae, brown algae (Phaeophyceae and the red algae (Rhodophyceae collected from the intertidal area of the Sudanese Red Sea coast near Port Sudan. Methods: Methanol was used for extracting the active principles of the algae and the disc diffusion method was performed to examine the activity and the minimum inhibitory concentration of the samples against four pathogenic bacteria and two fungi. Results: All tested algal extracts exhibited considerable bioactivity and inhibited the growth of all pathogenic microorganisms under investigation. The green alga Caulerpa racemosa produced the maximum inhibition zone (21 mm against Candida albicans while the red alga Laurencia papillosa showed low antimicrobial activity with the minimum inhibition zone of 10 mm against Pseudomonas aeruginosa. The tested algal extracts did not show any special antimicrobial influence on the selected microorganisms when they were considered as Grampositive and Gram-negative bacteria and fungi but the most efficient methanolic extracts in inhibiting microbial growth were those of green macroalgae followed by the brown and the red macroalgae respectively. Conclusions: The study demonstrated that the tested marine macroalgae from Sudanese Red Sea coast may represent a potential and alternative source for secondary metabolites with antimicrobial activity.

  10. Antimicrobial activity of methanolic extracts of selected marine macroalgae against some pathogenic microorganisms

    Institute of Scientific and Technical Information of China (English)

    Ehab Omer Abdalla; Mohammed Taha Abdalla Shigidi; Hassan Elsubki Khalid; Nahid Abdel Rahim Osman

    2016-01-01

    Objective:To evaluate the antimicrobial activity of methanolic extracts of six marine macroalgae belonging to green algae (Chlorophyceae), brown algae (Phaeophyceae) and the red algae (Rhodophyceae) collected from the intertidal area of the Sudanese Red Sea coast near Port Sudan. Methods:Methanol was used for extracting the active principles of the algae and the disc diffusion method was performed to examine the activity and the minimum inhibitory concentration of the samples against four pathogenic bacteria and two fungi. Results: All tested algal extracts exhibited considerable bioactivity and inhibited the growth of all pathogenic microorganisms under investigation. The green alga Caulerpa racemosa produced the maximum inhibition zone (21 mm) againstCandida albicans while the red alga Laurencia papillosa showed low antimicrobial activity with the minimum inhibition zone of 10 mm againstPseudomonas aeruginosa. The tested algal extracts did not show any special antimicrobial influence on the selected microorganisms when they were considered as Gram-positive and Gram-negative bacteria and fungi but the most efficient methanolic extracts in inhibiting microbial growth were those of green macroalgae followed by the brown and the red macroalgae respectively. Conclusions: The study demonstrated that the tested marine macroalgae from Sudanese Red Sea coast may represent a potential and alternative source for secondary metabolites with antimicrobial activity.

  11. Anti-Inflammatory and Antimicrobial activity of Flacourtia Ramontchi Leaves

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    Sulbha Lalsare

    2011-06-01

    Full Text Available The literature survey revealed that a very merge amount of pharmacological work has been carried out on Flacourtia ramontchi. Also it was observed from the Ayurvedic literature and Ethnobotanical studies that the plant is very useful in treating inflammation and infectious diseases but no scientific investigation has been done in such direction. Very merge work has been done regarding phytochemical and pharmacological effectiveness on this plant. Successive extraction of the leaves with solvents of increasing polarity; preliminary phytochemical studies of different extracts; screening of chloroform, methanol and hydromethanolic extracts for anti-inflammatory (by Carrageenan induced rat paw model and antimicrobial activity (by Cup and plate method and thin layer chromatographic studies of active extracts using mobile phase i.e. chloroform and methanol. The results clearly indicate that all three extracts i.e. chloroform, methanol and hydromethanolic, of the leaves having anti-inflammatory activity. But the chloroform and methano extract showed promising results and even chloroform extract at the dose 150mg/kg exhibits equipotent anti-inflammatory activity as that of the standard Indomethacin. Methanol extract possess broad-spectrum antimicrobial activity at concentration 10000 mg/ml whereas hydromethanolic and chloroform extracts having more or less antimicrobial activity.

  12. In Vitro Antimicrobial and Antiproliferative Activity of Amphipterygium adstringens

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    A. Rodriguez-Garcia

    2015-01-01

    Full Text Available Amphipterygium adstringens is a plant widely used in Mexican traditional medicine for its known anti-inflammatory and antiulcer properties. In this work, we evaluated the in vitro antimicrobial and antiproliferative activities of the methanolic extract of A. adstringens against oral pathogens such as Streptococcus mutans, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Candida albicans, and Candida dubliniensis, using microdilution (MIC and agar diffusion methods (MBC, and the antiproliferative activity evaluating total growth inhibition (TGI by staining the protein content with sulforhodamine B (SRB, using nine human cancer cell lines. Crude extract (CE of A. adstringens showed some degree of activity against one or more of the strains with a MIC from 0.125 mg/mL to 63 mg/mL and MBC from 1.6 to 6.3 mg/mL and cytotoxic activity, particularly against NCI-ADR/RES, an ovarian cell line expressing multiple resistance drugs phenotype. The CE is a complex mixture of possible multitarget metabolites that could be responsible for both antimicrobial and antiproliferative activities, and further investigation is required to elucidate the identity of active compounds. Nevertheless the CE itself is useful in the development of new antimicrobial treatment based on natural products to prevent oral diseases and as alternative natural source for cancer treatment and prevention.

  13. Antioxidant, Antimicrobial Activity and Toxicity Test of Pilea microphylla

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    Amir Modarresi Chahardehi

    2010-01-01

    Full Text Available A total of 9 plant extracts were tested, using two different kinds of extracting methods to evaluate the antioxidant and antimicrobial activities from Pilea microphylla (Urticaceae family and including toxicity test. Antioxidant activity were tested by using DPPH free radical scavenging, also total phenolic contents and total flavonoid contents were determined. Toxicity assay carried out by using brine shrimps. Methanol extract of method I (ME I showed the highest antioxidant activity at 69.51±1.03. Chloroform extract of method I (CE I showed the highest total phenolic contents at 72.10±0.71 and chloroform extract of method II (CE II showed the highest total flavonoid contents at 60.14±0.33. The antimicrobial activity of Pilea microphylla extract was tested in vitro by using disc diffusion method and minimum inhibitory concentration (MIC. The Pilea microphylla extract showed antibacterial activity against some Gram negative and positive bacteria. The extracts did not exhibit antifungal and antiyeast activity. The hexane extract of method I (HE I was not toxic against brine shrimp (LC50 value was 3880 μg/ml. Therefore, the extracts could be suitable as antimicrobial and antioxidative agents in food industry.

  14. THE ANTIMICROBIAL ACTIVITY OF SOME EXTRACTS OF FERN GAMETOPHYTES

    OpenAIRE

    Ionica Deliu; Carmen Bejan; Emilia Vişoiu; Liliana Cristina Soare

    2013-01-01

    The nature freely offers us many resources for health and beauty. The ferns and their therapeutic properties are less exploit in Romania, except Lycopodium clavatum and Equisetum arvense. Some of the fern properties were demonstrated, like antioxidant, antimicrobial, antiviral, antihelmintic properties. Plants are reasonable alternative to synthetic drugs, avoid the side effect and high cost of synthetic drugs production. Also, the drug resistance bacteria can be controlled using plant derive...

  15. An optical tweezer-based study of antimicrobial activity of silver nanoparticles

    Indian Academy of Sciences (India)

    Yogesha; Sarbari Bhattacharya; M K Rabinal; Sharath Ananthamurthy

    2012-08-01

    Understanding and characterizing microbial activity reduction in the presence of antimicrobial agents can help in the design and manufacture of antimicrobial drugs. We demonstrate the use of an optical tweezer setup in recording the changes in bacterial activity with time, induced by the presence of foreign bodies in a bacterial suspension. This is achieved by monitoring the fluctuations of an optically trapped polystyrene bead immersed in it. Examining the changes in the fluctuation pattern of the bead with time provides an accurate characterization of the reduction in the microbial activity. Here, we report on the effect of addition of silver nanoparticles on bacterial cultures of Pseudomonas aeroginosa, Escherichia coli and Bacillus subtilis. We observe a decrease in the bacterial activity with time for the investigated bacterial samples. This method in our opinion, enables one to track changes in bacterial activity levels as a function of time of contact with the antibacterial agent with greater efficacy than traditional cell counting methods.

  16. Antimicrobial activity of chicken NK-lysin against Eimeria sporozoites.

    Science.gov (United States)

    Hong, Yeong H; Lillehoj, Hyun S; Siragusa, Gregory R; Bannerman, Douglas D; Lillehoj, Erik P

    2008-06-01

    NK-lysin is an antimicrobial and antitumor polypeptide that is considered to play an important role in innate immunity. Chicken NK-lysin is a member of the saposin-like protein family and exhibits potent antitumor cell activity. To evaluate the antimicrobial properties of chicken NK-lysin, we examined its ability to reduce the viability of various bacterial strains and two species of Eimeria parasites. Culture supernatants from COS7 cells transfected with a chicken NK-lysin cDNA and His-tagged purified NK-lysin from the transfected cells both showed high cytotoxic activity against Eimeria acervulina and Eimeria maxima sporozoites. In contrast, no bactericidal activity was observed. Further studies using synthetic peptides derived from NK-lysin may be useful for pharmaceutical and agricultural uses in the food animal industry.

  17. Phytochemical screening, antioxidant, and antimicrobial activities of the crude leaves′ extract from Ipomoea batatas (L. Lam

    Directory of Open Access Journals (Sweden)

    Márcia Thaís Pochapski

    2011-01-01

    Full Text Available Background: Ipomoea batatas (L. Lam., popularly known as sweet potato (SP, has played an important role as an energy and a phytochemical source in human nutrition and animal feeding. Ethnopharmacological data show that SP leaves have been effectively used in herbal medicine to treat inflammatory and/or infectious oral diseases in Brazil. The aim of this research was to evaluate the phytochemical, antioxidant, and antimicrobial activities of the crude leaves′ extract of SP leaves. Materials and Methods: The screening was performed for triterpenes/steroids, alkaloids, anthraquinones, coumarins, flavonoids, saponins, tannins, and phenolic acids. The color intensity or the precipitate formation was used as analytical responses to these tests. The total antioxidant capacity was evaluated by the phosphomolybdenum complex method. Antimicrobial activity was made by agar disk and agar well diffusion tests. Results: The phytochemical screening showed positive results for triterpenes/steroids, alkaloids, anthraquinones, coumarins, flavonoids, saponins, tannins, and phenolic acids. Total contents of 345.65, 328.44, and 662.02 mg were respectively obtained for alkaloids, anthraquinones, and phenolic compounds in 100 g of the dry sample. The total antioxidant capacity was 42.94% as compared to ascorbic acid. For antimicrobial studies, no concentration of the SP freeze dried extract was able to inhibit the growth of Streptococcus mutans, S. mitis, Staphylococcus aureus, and Candida albicans in both agar disk and agar well diffusion tests. Conclusions: SP leaves demonstrated the presence of secondary metabolites with potential biological activities. No antimicrobial activity was observed.

  18. Chemical compositions and antimicrobial activities of four different Anatolian propolis samples.

    Science.gov (United States)

    Uzel, Ataç; Sorkun, Kadriye; Onçağ, Ozant; Cogŭlu, Dilşah; Gençay, Omür; Salih, Bekir

    2005-01-01

    Propolis means a gum that is gathered by bees from various plants. It is known for its biological properties, having antibacterial, antifungal and healing properties. The aims of this study were to evaluate the antimicrobial activity of four different Anatolian propolis samples on different groups of microorganisms including some oral pathogens and comparison between their chemical compositions. Ethanol extracts of propolis (EEP) were prepared from four different Anatolian propolis samples and examined whether EEP inhibit the growth of the test microorganisms or not. For the antimicrobial activity assays, minimum inhibitory concentrations (MIC) were determined by using macrodilution method. The MIC values of the most effective propolis (TB) were 2 microg/ml for Streptococcus sobrinus and Enterococcus faecalis, 4 microg/ml for Micrococcus luteus, Candida albicans and C. krusei, 8 microg/ml for Streptococcus mutans, Staphylococcus aureus, Staphylococcus epidermidis and Enterobacter aerogenes, 16 microg/ml for Escherichia coli and C. tropicalis and 32 microg/ml for Salmonella typhimurium and Pseudomonas aeruginosa. The chemical compositions of EEP's were determined by high-temperature high-resolution gas chromatography coupled to mass spectrometry. The main compounds of four Anatolian propolis samples were flavonoids such as pinocembrin, pinostropin, isalpinin, pinobanksin, quercetin, naringenin, galangine and chrysin. Although propolis samples were collected from different regions of Anatolia all showed significant antimicrobial activity against the Gram positive bacteria and yeasts. Propolis can prevent dental caries since it demonstrated significant antimicrobial activity against the microorganisms such as Streptococcus mutans, Streptococcus sobrinus and C. albicans, which involves in oral diseases.

  19. Phytochemical screening, antioxidant, and antimicrobial activities of the crude leaves’ extract from Ipomoea batatas (L.) Lam

    Science.gov (United States)

    Pochapski, Márcia Thaís; Fosquiera, Eliana Cristina; Esmerino, Luís Antônio; dos Santos, Elizabete Brasil; Farago, Paulo Vitor; Santos, Fábio André; Groppo, Francisco Carlos

    2011-01-01

    Background: Ipomoea batatas (L.) Lam., popularly known as sweet potato (SP), has played an important role as an energy and a phytochemical source in human nutrition and animal feeding. Ethnopharmacological data show that SP leaves have been effectively used in herbal medicine to treat inflammatory and/or infectious oral diseases in Brazil. The aim of this research was to evaluate the phytochemical, antioxidant, and antimicrobial activities of the crude leaves’ extract of SP leaves. Materials and Methods: The screening was performed for triterpenes/steroids, alkaloids, anthraquinones, coumarins, flavonoids, saponins, tannins, and phenolic acids. The color intensity or the precipitate formation was used as analytical responses to these tests. The total antioxidant capacity was evaluated by the phosphomolybdenum complex method. Antimicrobial activity was made by agar disk and agar well diffusion tests. Results: The phytochemical screening showed positive results for triterpenes/steroids, alkaloids, anthraquinones, coumarins, flavonoids, saponins, tannins, and phenolic acids. Total contents of 345.65, 328.44, and 662.02 mg were respectively obtained for alkaloids, anthraquinones, and phenolic compounds in 100 g of the dry sample. The total antioxidant capacity was 42.94% as compared to ascorbic acid. For antimicrobial studies, no concentration of the SP freeze dried extract was able to inhibit the growth of Streptococcus mutans, S. mitis, Staphylococcus aureus, and Candida albicans in both agar disk and agar well diffusion tests. Conclusions: SP leaves demonstrated the presence of secondary metabolites with potential biological activities. No antimicrobial activity was observed. PMID:21716926

  20. The Influence of Interfering Substances on the Antimicrobial Activity of Selected Quaternary Ammonium Compounds

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    Paula A. Araújo

    2013-01-01

    Full Text Available Standard cleaning processes may not remove all the soiling typically found in food industry, such as carbohydrates, fats, or proteins. Contaminants have a high impact in disinfection as their presence may reduce the activity of disinfectants. The influence of alginic acid, bovine serum albumin, yeast extract, and humic acids was assessed on the antimicrobial activities of benzalkonium chloride and cetyltrimethyl ammonium bromide against Bacillus cereus vegetative cells and Pseudomonas fluorescens. The bacteria (single and consortium were exposed to surfactants (single and combined in the absence and presence of potential disinfection interfering substances. The antimicrobial effects of the surfactants were assessed based on the bacterial respiratory activity measured by oxygen uptake rate due to glucose oxidation. The tested surfactants were efficient against both bacteria (single and consortium with minimum bactericidal concentrations ranging from 3 to 35 mg·L−1. The strongest effect was caused by humic acids that severely quenched antimicrobial action, increasing the minimum bactericidal concentration of the surfactants on P. fluorescens and the consortium. The inclusion of the other interfering substances resulted in mild interferences in the antibacterial activity. This study clearly demonstrates that humic acids should be considered as an antimicrobial interfering substance in the development of disinfection strategies.

  1. The Influence of Interfering Substances on the Antimicrobial Activity of Selected Quaternary Ammonium Compounds.

    Science.gov (United States)

    Araújo, Paula A; Lemos, Madalena; Mergulhão, Filipe; Melo, Luís; Simões, Manuel

    2013-01-01

    Standard cleaning processes may not remove all the soiling typically found in food industry, such as carbohydrates, fats, or proteins. Contaminants have a high impact in disinfection as their presence may reduce the activity of disinfectants. The influence of alginic acid, bovine serum albumin, yeast extract, and humic acids was assessed on the antimicrobial activities of benzalkonium chloride and cetyltrimethyl ammonium bromide against Bacillus cereus vegetative cells and Pseudomonas fluorescens. The bacteria (single and consortium) were exposed to surfactants (single and combined) in the absence and presence of potential disinfection interfering substances. The antimicrobial effects of the surfactants were assessed based on the bacterial respiratory activity measured by oxygen uptake rate due to glucose oxidation. The tested surfactants were efficient against both bacteria (single and consortium) with minimum bactericidal concentrations ranging from 3 to 35 mg·L(-1). The strongest effect was caused by humic acids that severely quenched antimicrobial action, increasing the minimum bactericidal concentration of the surfactants on P. fluorescens and the consortium. The inclusion of the other interfering substances resulted in mild interferences in the antibacterial activity. This study clearly demonstrates that humic acids should be considered as an antimicrobial interfering substance in the development of disinfection strategies.

  2. Synthesis and antimicrobial activity of 2-chloroquinoline incorporated pyrazoline derivatives

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    Sandhya Bawa

    2009-01-01

    Full Text Available Purpose : A series of 2-chloroquinoline containing pyrazoline derivatives having 3,4-dichloro/ 3,4-dimethoxy in the phenyl ring were synthesized and screened for their antimicrobial activity against a panel of bacterial and fungal strains. Materials and Methods : The structures of the newly synthesized compounds were established on the basis of spectral data obtained from the FTIR, 1H and 13C-NMR, and mass spectrometry. All the compounds were evaluated for their antibacterial activity against Escherichia coli (NCTC, 10418, Staphylococcus aureus (NCTC, 65710, and Pseudomonas aeruginosa (NCTC, 10662. The compounds were also tested for antifungal activity aganist Aspergillus niger (MTCC, 281, Aspergillus flavus (MTCC, 277, Monascus purpureus (MTCC, 369 and Penicillium citrinum (NCIM, 768 by the cup-plate method. Results : Among the compounds tested, 3,4-dichloro derivatives were comparatively more active in antimicrobial screening with respect to their 3,4-dimethoxy analog. Conclusion : A careful analysis of the antimicrobial activity data of the compounds revealed that compounds 3a, 3b, 3c, and 3e exhibited potent antibacterial

  3. Antimicrobial activity of aqueous and methanolic extracts of pomegranate fruit skin

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    Ali Sadeghian

    2011-09-01

    Conclusion: The extracts from pomegranate fruit skin possess strong antimicrobial activity against the tested microorganisms. Therefore this plant could be an important source of new antimicrobial compounds to treat bacterial and fungal infections.

  4. Antioxidant, antimicrobial and anticancer activity of the lichens Cladonia furcata, Lecanora atra and Lecanora muralis

    Science.gov (United States)

    2011-01-01

    Background The aim of this study is to investigate in vitro antioxidant, antimicrobial and anticancer activity of the acetone extracts of the lichens Cladonia furcata, Lecanora atra and Lecanora muralis. Methods Antioxidant activity was evaluated by five separate methods: free radical scavenging, superoxide anion radical scavenging, reducing power, determination of total phenolic compounds and determination of total flavonoid content. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method against six species of bacteria and ten species of fungi. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using MTT method. Results Of the lichens tested, Lecanora atra had largest free radical scavenging activity (94.7% inhibition), which was greater than the standard antioxidants. Moreover, the tested extracts had effective reducing power and superoxide anion radical scavenging. The strong relationships between total phenolic and flavonoid contents and the antioxidant effect of tested extracts were observed. Extract of Cladonia furcata was the most active antimicrobial agent with minimum inhibitory concentration values ranging from 0.78 to 25 mg/mL. All extracts were found to be strong anticancer activity toward both cell lines with IC50 values ranging from 8.51 to 40.22 μg/mL. Conclusions The present study shows that tested lichen extracts demonstrated a strong antioxidant, antimicrobial and anticancer effects. That suggest that lichens may be used as as possible natural antioxidant, antimicrobial and anticancer agents to control various human, animal and plant diseases. PMID:22013953

  5. Antioxidant, antimicrobial and anticancer activity of the lichens Cladonia furcata, Lecanora atra and Lecanora muralis

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    Stanojković Tatjana P

    2011-10-01

    Full Text Available Abstract Background The aim of this study is to investigate in vitro antioxidant, antimicrobial and anticancer activity of the acetone extracts of the lichens Cladonia furcata, Lecanora atra and Lecanora muralis. Methods Antioxidant activity was evaluated by five separate methods: free radical scavenging, superoxide anion radical scavenging, reducing power, determination of total phenolic compounds and determination of total flavonoid content. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method against six species of bacteria and ten species of fungi. Anticancer activity was tested against FemX (human melanoma and LS174 (human colon carcinoma cell lines using MTT method. Results Of the lichens tested, Lecanora atra had largest free radical scavenging activity (94.7% inhibition, which was greater than the standard antioxidants. Moreover, the tested extracts had effective reducing power and superoxide anion radical scavenging. The strong relationships between total phenolic and flavonoid contents and the antioxidant effect of tested extracts were observed. Extract of Cladonia furcata was the most active antimicrobial agent with minimum inhibitory concentration values ranging from 0.78 to 25 mg/mL. All extracts were found to be strong anticancer activity toward both cell lines with IC50 values ranging from 8.51 to 40.22 μg/mL. Conclusions The present study shows that tested lichen extracts demonstrated a strong antioxidant, antimicrobial and anticancer effects. That suggest that lichens may be used as as possible natural antioxidant, antimicrobial and anticancer agents to control various human, animal and plant diseases.

  6. Antimicrobial activity of human prion protein is mediated by its N-terminal region.

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    Mukesh Pasupuleti

    Full Text Available BACKGROUND: Cellular prion-related protein (PrP(c is a cell-surface protein that is ubiquitously expressed in the human body. The multifunctionality of PrP(c, and presence of an exposed cationic and heparin-binding N-terminus, a feature characterizing many antimicrobial peptides, made us hypothesize that PrP(c could exert antimicrobial activity. METHODOLOGY AND PRINCIPAL FINDINGS: Intact recombinant PrP exerted antibacterial and antifungal effects at normal and low pH. Studies employing recombinant PrP and N- and C-terminally truncated variants, as well as overlapping peptide 20mers, demonstrated that the antimicrobial activity is mediated by the unstructured N-terminal part of the protein. Synthetic peptides of the N-terminus of PrP killed the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, and the Gram-positive Bacillus subtilis and Staphylococcus aureus, as well as the fungus Candida parapsilosis. Fluorescence studies of peptide-treated bacteria, paired with analysis of peptide effects on liposomes, showed that the peptides exerted membrane-breaking effects similar to those seen after treatment with the "classical" human antimicrobial peptide LL-37. In contrast to LL-37, however, no marked helix induction was detected for the PrP-derived peptides in presence of negatively charged (bacteria-mimicking liposomes. PrP furthermore showed an inducible expression during wounding of human skin ex vivo and in vivo, as well as stimulation of keratinocytes with TGF-alpha in vitro. CONCLUSIONS: The demonstration of an antimicrobial activity of PrP, localisation of its activity to the N-terminal and heparin-binding region, combined with results showing an increased expression of PrP during wounding, indicate that PrPs could have a previously undisclosed role in host defense.

  7. Antimicrobial and antihyperglycemic activities of Musa paradisiaca flowers

    Institute of Scientific and Technical Information of China (English)

    Sunil Jawla; Y Kumar; MSY Khan

    2012-01-01

    Objective: To screen the antimicrobial and antihyperglycemic activities of Musa paradisiaca (M. paradisiaca) flowers. Methods: The EtOH and EtOH: water (1:1) extracts of M. paradisiaca flowers were screened for antibacterial and antifungal activity against standard strains of Bacillussubtilis (K. pneumoniae), Proteus mirabilis (P. mirabilis), Pseudomonas aeruginosa (P. aeruginosa),Streptococcus pneumoniae (B. subtilis), Bacillus cereus (B. cereus), Escherichia coli (E. coli), Klebsiella pneumoniae typhimurium (S. typhimurium) and Candida albicans (C. albicans), Cryptococcus albidus (C.albidus (S. pneumoniae), Staphylococcus aureus (S. aureus), Salmonella ) against amikacin and clotrimazole respectively. Both the extracts were also administered to normal and alloxan induced diabetic rats. The blood glucose levels were measured daily after oral administration of extracts at doses of 100, 250 and 500 mg/(kg.d). Result: The EtOH and EtOH:water (1:1) extracts exhibited antimicrobial activity with minimum inhibitory concentrations ranging from 5.62-25.81 and 7.60-31.50 μg/mL respectively. Both the extracts reversed the permanent hyperglycemia within a week in alloxan induced diabetic rats. The EtOH extract (250 mg/kg) was found to be 7.69% more potent hypoglycemic effect than standard oral hypoglycemic drug, glibenclamide 0.2 mg/kg b.w., respectively. Conclusion: The alcoholic extracts of M. paradisiaca flowers showed potent antihyperglycemic and moderate antimicrobial activities.

  8. Trigona laeviceps propolis from Thailand: antimicrobial, antiproliferative and cytotoxic activities.

    Science.gov (United States)

    Umthong, Supawadee; Puthong, Songchan; Chanchao, Chanpen

    2009-01-01

    Propolis is one of the natural bee products which has long been used as a crude preventative and prophylactic medicine, and has been reported to possess antibacterial, antiviral, anti-inflammatory, antioxidative and anticancer properties. Propolis of the stingless bee, Trigona laeviceps, was extracted by water or methanol at 35% (w/v) yielding a crude water or a methanolic extract at 60 and 80 mg/ml, respectively, which is 17.1 and 22.9% (w/w) of the total propolis, respectively. The antimicrobial activity of both crude extracts was assayed on four selected pathogenic microbes by using the agar well diffusion method. The results suggested that both water and methanolic crude extracts have some antimicrobial activities, water extract has greater antimicrobial activity than methanolic extract. The relative order of sensitivity of the four microbes were, however, the same between the two extracts from the most to least sensitive, S. aureus > E. coli > C. albicans > A. niger, with indeed no observed growth inhibition of A. niger at all. Antiproliferative and cytotoxic affects were tested on the colon carcinoma cell line, SW620, using the three parameters: (1) MTT assay; (2) cell morphology; and (3) the fragmentation of genomic DNA. The water extract of propolis showed a higher antiproliferative activity than that of methanolic extract to SW620 cells, additionally both appeared to cause cell death by necrosis.

  9. Antimicrobial activities of endophytic fungi isolated from Ophiopogon japonicus (Liliaceae

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    Liang Hanqiao

    2012-11-01

    Full Text Available Abstract Background Drug resistance in bacteria has become a global concern and the search for new antibacterial agents is urgent and ongoing. Endophytes provide an abundant reservoir of bioactive metabolites for medicinal exploitation, and an increasing number of novel compounds are being isolated from endophytic fungi. Ophiopogon japonicus, containing compounds with antibacterial activity, is a traditional Chinese medicinal plant used for eliminating phlegm, relieving coughs, latent heat in the lungs, and alleviating diabetes mellitus. We investigated the antimicrobial activities of 30 strains of O. japonicus. Methods Fungal endophytes were isolated from roots and stems of O. japonicus collected from Chongqing City, southwestern China. Mycelial extracts (MC and fermentation broth (FB were tested for antimicrobial activity using peptide deformylase (PDF inhibition fluorescence assays and MTT cell proliferation assays. Results A total of 30 endophytic strains were isolated from O. japonicus; 22 from roots and eight from stems. 53.33% of the mycelial extracts (MC and 33.33% of the fermentation broths (FB displayed potent inhibition of PDF. 80% of MC and 33.33% of FB significantly inhibited Staphylococcus aureus. 70% of MC and 36.67% of FB showed strong activities against Cryptococcus neoformans. None showed influence on Escherichia coli. Conclusion The secondary metabolites of endophytic fungi from O. japonicus are potential antimicrobial agents.

  10. Antimicrobial and Cytotoxic Activities of Extracts from Laurus nobilis Leaves

    KAUST Repository

    Felemban, Shaza

    2011-05-01

    The cytotoxic activity and antimicrobial properties of crude extracts from Laurus nobilis were investigated. With the use of the organic solvents, methanol and ethanol, crude extracts were obtained. To determine the availability of active bio‐compounds, an analysis using liquid chromatography was conducted. The crude extract was also tested for antimicrobial activity. The disc diffusion method was used against the bacterium Escherichia coli. The results showed a weak antimicrobial activity against E. coli. For cytotoxicity testing, the crude extract was studied on four cell-­lines: human breast adenocarcinoma, human embryonic kidney, HeLa (human cervical adenocarcinoma), and human lung fibroblast. From the alamarBlue® assay results, the extracts most potently affected the cell-­lines of human breast adenocarcinoma and human embryonic kidney. Using the lactate dehydrogenase (LDH) assay, an effect on human embryonic kidney was most prominent. With these findings, a suggestion that the crude extract of Laurus nobilis may have antiproliferative properties is put forth, with the possibility of this mechanism being induction of apoptosis with the involvement of Nuclear Factor Kappa κB (NF κB).

  11. Synthesis, antimicrobial and antioxidative activity of some new isatin derivatives

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    Šekularac Gavrilo M.

    2014-01-01

    Full Text Available The isatin derivatives, Schiff bases, were synthesized by the reaction of isatin and various substituted primary amines and characterized by several spectroscopic methods. Investigation of the antimicrobial activity of the synthesized compounds was performed by the agar dilution method, against different strains of bacteria and one fungi. The antioxidative activity of the synthesized compounds was also determined. Some of the compounds have shown the significant activity against the selected strains of microorganisms and the antioxidative activity. [Projekat Ministarstva nauke Republike Srbije, br. 172013 i III 46010

  12. Antimicrobial activity of some medicinal barks used in Peruvian Amazon.

    Science.gov (United States)

    Kloucek, P; Svobodova, B; Polesny, Z; Langrova, I; Smrcek, S; Kokoska, L

    2007-05-04

    The aim of this study was to evaluate the antimicrobial activity of six barks traditionally used in Callería District (Ucayali Department, Peru) for treating conditions likely to be associated with microorganisms. Ethanol extracts of stem barks of Abuta grandifolia (Menispermaceae), Dipteryx micrantha (Leguminosae), Cordia alliodora (Boraginaceae), Naucleopsis glabra (Moraceae), Pterocarpus rohrii (Leguminosae), and root bark of Maytenus macrocarpa (Celastraceae) were tested against nine bacteria and one yeast using the broth microdilution method. All plants possessed significant antimicrobial effect, however, the extract of Naucleopsis glabra exhibited the strongest activity against Gram-positive bacteria (MICs ranging from 62.5 to 125 microg/ml), while the broadest spectrum of action was shown by the extract of Maytenus macrocarpa, which inhibited all the strains tested with MICs ranging from 125 to 250 microg/ml.

  13. Flavonoids from Halostachys caspica and Their Antimicrobial and Antioxidant Activities

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    Fuyu Yang

    2010-11-01

    Full Text Available Seven flavonoids have been isolated from the aerial parts of Halostachys caspica C. A. Mey. (Chenopodiaceae for the first time. By means of physicochemical and spectrometric analysis, they were identified as luteolin (1, chrysin (2, chrysin 7-O-β-D-glucopyranoside (3, quercetin (4, quercetin 3-O-β-D-glucopyranoside (5, isorhamentin-3-O-β-D-glucopyranoside (6, and isorhamentin-3-O-β-D-rutinoside (7. All flavonoids were evaluated to show a broad antimicrobial spectrum of activity on microorganisms including seven bacterial and one fungal species as well as pronounced antioxidant activity. Among them, the aglycones with relatively low polarity had stronger bioactivity than their glycosides. The results suggested that the isolated flavonoids could be used for future development of antimicrobial and antioxidant agents, and also provided additional data for supporting the use of H. caspica as forage.

  14. Antimicrobial activity and chemical investigation of Brazilian Drosera

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    Dalva Trevisan Ferreira

    2004-11-01

    Full Text Available The antimicrobial activity of three different extracts (hexanic, ethyl acetate, methanol obtained from Brazilian Drosera species (D. communis, D. montana var. montana, D. brevifolia, D. villosa var. graomogolensis, D. villosa var. villosa, Drosera sp. 1, and Drosera sp. 2 were tested against Staphylococcus aureus (ATCC 25923, Enterococcus faecium (ATCC23212, Pseudomonas aeruginosa (ATCC27853, Escherichia coli (ATCC11229, Salmonella choleraesuis (ATCC10708, Klebsiella pneumoniae (ATCC13883, and Candida albicans (a human isolate. Better antimicrobial activity was observed with D. communis and D. montana var. montana ethyl acetate extracts. Phytochemical analyses from D. communis, D. montana var. montana and D. brevifolia yielded 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin; long chain aliphatic hydrocarbons were isolated from D. communis and from D. villosa var. villosa, a mixture of long chain aliphatic alcohols and carboxylic acids, was isolated from D. communis and 3b-O-acetylaleuritolic acid from D. villosa var. villosa.

  15. Chemical composition, antimicrobial, antiradical and anticholinesterase activity of the essential oil of Pulicaria stephanocarpa from Soqotra.

    Science.gov (United States)

    Ali, Nasser A Awadh; Crouch, Rebecca A; Al-Fatimi, Mohamed A; Arnold, Norbert; Teichert, Axel; Setzer, William N; Wessjohann, Ludger

    2012-01-01

    The chemical composition of the hydrodistilled leaf essential oil from Pulicaria stephanocarpa Balf. Fil was determined by GC-MS analysis, and its antimicrobial, antioxidant and anticholinesterase (AChE) activities were evaluated. Eighty-three compounds were identified representing 97.2% of the total oil. (E)-Caryophyllene 13.4%, (E)-nerolidol 8.5%, caryophyllene oxide 8.5%, alpha-cadinol 8.2% spathulenol 6.8% and tau-cadinol 4.7%, were the main components. Antimicrobial activity of the oil, evaluated using the disc diffusion and broth dilution methods, demonstrated the highest susceptibility on Gram-positive bacteria and Candida albicans. The free radical scavenging ability of the oil was assessed by the DPPH assay to show antiradical activity with IC50 of 330 microg/mL. Moreover, the oil revealed an AChE inhibitory activity of 47% at a concentration of 200 microg/mL using Ellman's method.

  16. Antimicrobial activity of Wedelia trilobata crude extracts.

    Science.gov (United States)

    Taddei, A; Rosas-Romero, A J

    1999-05-01

    A biological screening of activity against Gram-positive and Gram-negative bacteria, yeasts, and fungi of crude extracts from Wedelia trilobata is reported. The n-hexane extract showed antibacterial activity against Bacillus subtilis, Mycobacterium smegmatis, Staphylococcus aureus, and Staphylococcus epidermidis (Gram-positive bacteria); along with Proteus vulgaris, Pseudomonas aeruginosa, Salmonella group C, Salmonella paratyphi, and Shigella sonnei (Gram-negative bacteria). The ethyl acetate extract was active only against Salmonella group C; and the aqueous extract was inactive against the tested bacteria. None of the tested extracts showed biological activity against the yeasts (Candida albicans, Candida tropicalis, Rhodotorula rubra) or the fungi (Aspergillus flavus, Aspergillus niger, Mucor sp., Trichophyton rubrum).

  17. Investigation on antimicrobial activity and phytochemical screening of Randia spinosa (Thunb. Poir. and Dillenia pentagyna Roxb.

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    Irulandi Kokkaiah

    2016-10-01

    Full Text Available Objective: To evaluate phytochemicals and antimicrobial activity of Randia spinosa (Thunb. Poir. and Dillenia pentagyna Roxb. leaf extracts against human pathogens such as Gram positive bacteria (Streptococcus faecalis, Bacillus subtilis and Staphyllococcus aureus, Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, and a fungus Candida albicans. Methods: Antimicrobial activity of methanol, acetone and ethyl acetate extracts of the two plants against the human pathogens was investigated by agar well diffusion method, and qualitative phytochemical screening was conducted for the presence of phytoconstituents such as alkaloids, catechins, coumarins, flavonoids, phenols, quinones, saponins, steroids, tannins and terpenoids. Results: The qualitative phytochemical analysis showed the presence of diverse range of compounds like alkaloids, flavonoids, phenols, steroids, tannins, terpenoids and saponins. The plants exhibited broad spectrum of antimicrobial activities against all the tested bacterial and fungal pathogens. The maximum zone of inhibition was observed in methanol extracts when compared with acetone and ethyl acetate extracts. The present study demonstrated that the selected plants had promising effect on the bacterial and fungal pathogens. Conclusions: The phytochemicals in the plants may be potentially responsible for the antimicrobial efficacy of these medicinal plants.

  18. Amyloidogenic amyloid-β-peptide variants induce microbial agglutination and exert antimicrobial activity

    Science.gov (United States)

    Spitzer, Philipp; Condic, Mateja; Herrmann, Martin; Oberstein, Timo Jan; Scharin-Mehlmann, Marina; Gilbert, Daniel F.; Friedrich, Oliver; Grömer, Teja; Kornhuber, Johannes; Lang, Roland; Maler, Juan Manuel

    2016-01-01

    Amyloid-β (Aβ) peptides are the main components of the plaques found in the brains of patients with Alzheimer’s disease. However, Aβ peptides are also detectable in secretory compartments and peripheral blood contains a complex mixture of more than 40 different modified and/or N- and C-terminally truncated Aβ peptides. Recently, anti-infective properties of Aβ peptides have been reported. Here, we investigated the interaction of Aβ peptides of different lengths with various bacterial strains and the yeast Candida albicans. The amyloidogenic peptides Aβ1-42, Aβ2-42, and Aβ3p-42 but not the non-amyloidogenic peptides Aβ1-40 and Aβ2-40 bound to microbial surfaces. As observed by immunocytochemistry, scanning electron microscopy and Gram staining, treatment of several bacterial strains and Candida albicans with Aβ peptide variants ending at position 42 (Aβx-42) caused the formation of large agglutinates. These aggregates were not detected after incubation with Aβx-40. Furthermore, Aβx-42 exerted an antimicrobial activity on all tested pathogens, killing up to 80% of microorganisms within 6 h. Aβ1-40 only had a moderate antimicrobial activity against C. albicans. Agglutination of Aβ1-42 was accelerated in the presence of microorganisms. These data demonstrate that the amyloidogenic Aβx-42 variants have antimicrobial activity and may therefore act as antimicrobial peptides in the immune system. PMID:27624303

  19. Antimicrobial activity of filamentous fungi isolated from highly antibiotic-contaminated river sediment

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    K. Stefan Svahn

    2012-05-01

    Full Text Available Background: Filamentous fungi are well known for their production of substances with antimicrobial activities, several of which have formed the basis for the development of new clinically important antimicrobial agents. Recently, environments polluted with extraordinarily high levels of antibiotics have been documented, leading to strong selection pressure on local sentinel bacterial communities. In such microbial ecosystems, where multidrug-resistant bacteria are likely to thrive, it is possible that certain fungal antibiotics have become less efficient, thus encouraging alternative strategies for fungi to compete with bacteria. Methods: In this study, sediment of a highly antibiotic-contaminated Indian river was sampled in order to investigate the presence of cultivable filamentous fungi and their ability to produce substances with antimicrobial activity. Results: Sixty one strains of filamentous fungi, predominantly various Aspergillus spp. were identified. The majority of the Aspergillus strains displayed antimicrobial activity against methicillin-resistant Staphylococcus aureus, extended-spectrum beta-lactamase-producing Escherichia coli, vancomycin-resistant Enterococcus faecalis and Candida albicans. Bioassay-guided isolation of the secondary metabolites of A. fumigatus led to the identification of gliotoxin. Conclusion: This study demonstrated proof of principle of using bioassay-guided isolation for finding bioactive molecules.

  20. Antimicrobial activity of Uncaria tomentosa against oral human pathogens

    OpenAIRE

    Renzo Alberto Ccahuana-Vasquez; Silvana Soléo Ferreira dos Santos; Cristiane Yumi Koga-Ito; Antonio Olavo Cardoso Jorge

    2007-01-01

    Uncaria tomentosa is considered a medicinal plant used over centuries by the peruvian population as an alternative treatment for several diseases. Many microorganisms usually inhabit the human oral cavity and under certain conditions can become etiologic agents of diseases. The aim of the present study was to evaluate the antimicrobial activity of different concentrations of Uncaria tomentosa on different strains of microorganisms isolated from the human oral cavity. Micropulverized Uncaria t...

  1. Antimicrobial Activity of Xanthohumol and Its Selected Structural Analogues

    OpenAIRE

    Monika Stompor; Barbara Żarowska

    2016-01-01

    The objective of this study was to evaluate the antimicrobial activity of structural analogues of xanthohumol 1, a flavonoid compound found in hops (Humulus lupulus). The agar-diffusion method using filter paper disks was applied. Biological tests performed for selected strains of Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, fungi (Alternaria sp.), and yeasts (Rhodotorula rubra, Candida albicans) revealed that compounds with at least one hydroxyl group—...

  2. Synthesis and Antimicrobial Activity of SomeNovel Benzimidazolyl Chalcones

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    B. A. Baviskar

    2009-01-01

    Full Text Available Some novel benzimidazolyl chalcones were synthesized by condensation of N-(4-(1H-benzo[d]imidazol-2-ylphenylacetamide with aromatic aldehydes in presence of aqueous potassium hydroxide solution at room temperature. All the synthesized compounds were characterized on the basis of their IR, 1H NMR spectroscopic data and elemental analysis. All the compounds have been screened for antimicrobial activity by the cup-plate method.

  3. Synthesis and Antimicrobial Activity of SomeNovel Benzimidazolyl Chalcones

    OpenAIRE

    2009-01-01

    Some novel benzimidazolyl chalcones were synthesized by condensation of N-(4-(1H-benzo[d]imidazol-2-yl)phenyl)acetamide with aromatic aldehydes in presence of aqueous potassium hydroxide solution at room temperature. All the synthesized compounds were characterized on the basis of their IR, 1H NMR spectroscopic data and elemental analysis. All the compounds have been screened for antimicrobial activity by the cup-plate method.

  4. Synthesis and Antimicrobial Activity of Some Chalcone Derivatives

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    Y. Rajendra Prasad

    2008-01-01

    Full Text Available In an effort to develop antimicrobial agents, a series of chalcones were prepared by Claisen-Schmidt condensation of appropriate acetophenones with appropriate aromatic aldehydes in the presence of aqueous solution of potassium hydroxide and ethanol at room temperature. The synthesized compounds were characterized by means of their IR, 1H-NMR spectral data and elemental analysis. All the compounds were tested for their antibacterial and antifungal activities by the cup plate method.

  5. Antimicrobial activity of essential oils against Paenibacillus larvae

    OpenAIRE

    Gende, L. B.; Pires, Sância; Fernandez, N.J.; Damiani, M.; Churio, M.S.; Fritz, R.; Eguaras, M. J.

    2012-01-01

    American foulbrood is a serious bacterial disease that affects Apis mellifera colonies; the causative agent is Paenibacillus larvae [1 ]. The aim of the study was to evaluate in vitro the antimicrobial activity of 32 essential oils against P. larvae. Oils from 21 botanical species were analyzed by gas chromatography (CG and CG/EM). All essential oils were classified according to the composition of their main components in two groups: benzene ring compounds (BRC) and terpene com...

  6. Antimicrobial Activity of The Macrofungi Russula delica Fr.

    OpenAIRE

    Başaran DÜLGER; ŞEN, Fedai

    1999-01-01

    Extracts of Russula delica Fr. were prepared with Ethyl acetate, Acetone, Chloroform and Ethanol and antimicrobial activities of these exracts were examined on test microorganisms as follows: Escherichia coli ATCC 11230, Enterobacter aerogenes CCM 2531, Staphylococcus aureus ATCC 6538P, Staphylococcus epidermidis NRRL B-4377, Micrococcus luteus La 2971, Micrococcus flavus ATCC 14452, Bacillus subtilis ATCC 6633, Bacillus cereus ATCC 7064, Bacillus brevis ATCC 9999, Bacillus spharericus, ...

  7. THE ANTIMICROBIAL ACTIVITY OF SOME EXTRACTS OF FERN GAMETOPHYTES

    Directory of Open Access Journals (Sweden)

    Ionica Deliu

    2013-12-01

    Full Text Available The nature freely offers us many resources for health and beauty. The ferns and their therapeutic properties are less exploit in Romania, except Lycopodium clavatum and Equisetum arvense. Some of the fern properties were demonstrated, like antioxidant, antimicrobial, antiviral, antihelmintic properties. Plants are reasonable alternative to synthetic drugs, avoid the side effect and high cost of synthetic drugs production. Also, the drug resistance bacteria can be controlled using plant derived remedies. In this study the antimicrobial effect of methanolic and ethanolic extracts from three fern species were tested. The extracts were gained from gametophytic stage of ferns obtained in vitro. The most obvious effect was observed for Asplenium trichomanes-ramosum extract. The total polyphenols and flavonoids content were established, too.

  8. Determination of Yeasts Antimicrobial Activity in Milk and Meat Products

    Directory of Open Access Journals (Sweden)

    L.B. Roostita

    2011-12-01

    Full Text Available The research was arranged to isolate yeasts from livestock products and then the yeasts antimicrobial activity was tested towards putrefaction and pathogenic bacteria. Yeasts isolated from livestock products using Malt Extract Agar (MEA, the total yeasts population counted with using total plate count method, antimicrobial activity tested using diffusion methods against Pseudomonas aerugenes, Staphylococcus aureus and Escherichia coli and then the chosen isolate identified with using 18s RNA method. The results have shown that the total yeasts population on pasteurized cow’s milk were 1.2×106 cfu/g, fruit yoghurt 5.4×106 cfu/g, lamb meat 1×105 cfu/g, beef 1×105 cfu/g and beef sausages 1×106 cfu/g total yeasts population. Fruit yoghurt isolate shown the best antimicrobial activity with 35 mm clear zone diameter against Pseudomonas aerugenes, 8 mm clear zone diameter against Staphylococcus aureus and 10 mm clear zone diameter against Escherichia coli. The 18 s RNA test shown that fruit yoghurt isolate was 100% (FR3-F primer and 99% (FR3-R primer identical with Candida parapsilosis.

  9. Biocompatible cellulose-based superabsorbent hydrogels with antimicrobial activity.

    Science.gov (United States)

    Peng, Na; Wang, Yanfeng; Ye, Qifa; Liang, Lei; An, Yuxing; Li, Qiwei; Chang, Chunyu

    2016-02-10

    Current superabsorbent hydrogels commercially applied in the disposable diapers have disadvantages such as weak mechanical strength, poor biocompatibility, and lack of antimicrobial activity, which may induce skin allergy of body. To overcome these hassles, we have developed novel cellulose based hydrogels via simple chemical cross-linking of quaternized cellulose (QC) and native cellulose in NaOH/urea aqueous solution. The prepared hydrogel showed superabsorbent property, high mechanical strength, good biocompatibility, and excellent antimicrobial efficacy against Saccharomyces cerevisiae. The presence of QC in the hydrogel networks not only improved their swelling ratio via electrostatic repulsion of quaternary ammonium groups, but also endowed their antimicrobial activity by attraction of sections of anionic microbial membrane into internal pores of poly cationic hydrogel leading to the disruption of microbial membrane. Moreover, the swelling properties, mechanical strength, and antibacterial activity of hydrogels strongly depended on the contents of quaternary ammonium groups in hydrogel networks. The obtained data encouraged the use of these hydrogels for hygienic application such as disposable diapers.

  10. Antimicrobial activity of silver/starch/polyacrylamide nanocomposite.

    Science.gov (United States)

    Abdel-Halim, E S; Al-Deyab, Salem S

    2014-07-01

    A novel silver/starch/polyacrylamide nanocomposite hydrogel was prepared by grafting acrylamide onto starch in presence of silver nitrate by use of ammonium persulphate as an initiator and N,N-methylene-bisacrylamide as a crosslinking agent, then reducing the silver ions enclosed in the hydrogel structure to silver nanoparticles by treating the hydrogel with sodium hydroxide solution. All factors which affect the grafting/crosslinking reaction were optimized and the concentration of silver ion was changed from 0ppm to 50ppm. The produced nanocomposite hydrogel was characterized for its nanosilver content and the UV-spectra showed similar absorption spectra at wavelength 405nm for all AgNO3 concentrations but the plasmon showed increase in the intensity of the absorption peak as AgNO3 concentration incorporated to the hydrogel structure increases. The nanocomposite hydrogel was also characterized for its antimicrobial activity toward two types of bacteria and two types of fungi. The results showed that the hydrogel with 0ppm silver content has no antimicrobial activity, and that the antimicrobial activity expressed as inhibition zone increases as the silver content increases from 5ppm to 50ppm.

  11. Accepted 15 March 2012Available online 20 May 2012%Insecticidal, antimicrobial and antioxidant activities of bulb extracts of Allium sativum

    Institute of Scientific and Technical Information of China (English)

    Balaji Meriga; Ramgopal Mopuri; T MuraliKrishna

    2012-01-01

    ABSTRACT Objective:To evaluate the insecticidal, antimicrobial and antioxidant activities of bulb extracts ofAllium sativum(A. sativum).Methods:Dried bulbs ofA. sativum were extracted with different solvents and evaluated for insecticidal, antimicrobial and antioxidant activities.Results:Aqueous and methanol extracts showed highest insecticidal activity (mortality rate of81% and 64% respectively) against the larvae ofSpodoptera litura (S. litura) at a concentration of1 000 ppm. With regard to antimicrobial activity, aqueous extract exhibited antibacterial activity against gram positive (Bacillus subtilis, Staphylococcus aureu,) and gram negative (Escherichia coliandKlebsiella pneumonia) strains and antifungal activity againstCandida albicans. While methanol extract showed antimicrobial activity against all the tested micro organisms except two (Staphylococcus aureus andCandida albicans), the extracts of hexane, chloroform and ethyl acetate did not show any anti microbial activity. Minimum inhibitory concentration of aqueous and methanol extracts against tested bacterial and fungal strains was100-150 μg/mL. Antioxidant activity of the bulb extracts was evaluated in terms of inhibition of free radicals by 2, 2’-diphenly-1-picrylhydrazyl. Aqueous and methanol extracts exhibited strong antioxidant activity(80%-90% of the standard).Conclusions: Antioxidant and antimicrobial activity of A. sativum against the tested organisms therefore, provides scientific basis for its utilization in traditional and folk medicine. Also, our results demonstrated the insecticidal efficacy ofA. sativum againstS. litura, a polyphagous insect.

  12. LL-37 complexation with glycosaminoglycans in cystic fibrosis lungs inhibits antimicrobial activity, which can be restored by hypertonic saline.

    LENUS (Irish Health Repository)

    Bergsson, Gudmundur

    2009-07-01

    There is an abundance of antimicrobial peptides in cystic fibrosis (CF) lungs. Despite this, individuals with CF are susceptible to microbial colonization and infection. In this study, we investigated the antimicrobial response within the CF lung, focusing on the human cathelicidin LL-37. We demonstrate the presence of the LL-37 precursor, human cathelicidin precursor protein designated 18-kDa cationic antimicrobial protein, in the CF lung along with evidence that it is processed to active LL-37 by proteinase-3. We demonstrate that despite supranormal levels of LL-37, the lung fluid from CF patients exhibits no demonstrable antimicrobial activity. Furthermore Pseudomonas killing by physiological concentrations of exogenous LL-37 is inhibited by CF bronchoalveolar lavage (BAL) fluid due to proteolytic degradation of LL-37 by neutrophil elastase and cathepsin D. The endogenous LL-37 in CF BAL fluid is protected from this proteolysis by interactions with glycosaminoglycans, but while this protects LL-37 from proteolysis it results in inactivation of LL-37 antimicrobial activity. By digesting glycosaminoglycans in CF BAL fluid, endogenous LL-37 is liberated and the antimicrobial properties of CF BAL fluid restored. High sodium concentrations also liberate LL-37 in CF BAL fluid in vitro. This is also seen in vivo in CF sputum where LL-37 is complexed to glycosaminoglycans but is liberated following nebulized hypertonic saline resulting in increased antimicrobial effect. These data suggest glycosaminoglycan-LL-37 complexes to be potential therapeutic targets. Factors that disrupt glycosaminoglycan-LL-37 aggregates promote the antimicrobial effects of LL-37 with the caveat that concomitant administration of antiproteases may be needed to protect the now liberated LL-37 from proteolytic cleavage.

  13. Simple Activity Demonstrates Wind Energy Principles

    Science.gov (United States)

    Roman, Harry T.

    2012-01-01

    Wind energy is an exciting and clean energy option often described as the fastest-growing energy system on the planet. With some simple materials, teachers can easily demonstrate its key principles in their classroom. (Contains 1 figure and 2 tables.)

  14. Multilayer hydrogel coatings to combine hemocompatibility and antimicrobial activity.

    Science.gov (United States)

    Fischer, Marion; Vahdatzadeh, Maryam; Konradi, Rupert; Friedrichs, Jens; Maitz, Manfred F; Freudenberg, Uwe; Werner, Carsten

    2015-07-01

    While silver-loaded catheters are widely used to prevent early-onset catheter-related infections [1], long term antimicrobial protection of indwelling catheters remains to be achieved [2] and antiseptic functionalization of coatings often impairs their hemocompatibility characteristics. Therefore, this work aimed to capitalize on the antimicrobial properties of silver nanoparticles, incorporated in anticoagulant poly(ethylene glycol) (PEG)-heparin hydrogel coatings [3] on thermoplastic polyurethane materials. For prolonged antimicrobial activity, the silver-containing starPEG-heparin hydrogel layers were shielded with silver-free hydrogel layers of otherwise similar composition. The resulting multi-layered gel coatings showed long term antiseptic efficacy against Escherichia coli and Staphylococcus epidermidis strains in vitro, and similarly performed well when incubated with freshly drawn human whole blood with respect to hemolysis, platelet activation and plasmatic coagulation. The introduced hydrogel multilayer system thus offers a promising combination of hemocompatibility and long-term antiseptic capacity to meet an important clinical need.

  15. Antimicrobial activity of toothpastes containing natural extracts, chlorhexidine or triclosan.

    Science.gov (United States)

    De Rossi, Andiara; Ferreira, Danielly Cunha Araújo; da Silva, Raquel Assed Bezerra; de Queiroz, Alexandra Mussolino; da Silva, Léa Assed Bezerra; Nelson-Filho, Paulo

    2014-01-01

    The objective of this in vitro study was to evaluate the antimicrobial effect of toothpastes containing natural extracts, chlorhexidine or triclosan. The effectiveness of toothpastes containing natural extracts (Parodontax®), 0.12% chlorhexidine (Cariax®), 0.3% triclosan (Sanogil®) or fluoride (Sorriso®, control) was evaluated against yeasts, Gram-positive and Gram-negative bacteria using the disk diffusion method. Water was used as a control. Disks impregnated with the toothpastes were placed in Petri dishes containing culture media inoculated with 23 indicative microorganisms by the pour plate method. After incubation, the inhibition growth halos were measured and statistical analyses (α=0.05) were performed. The results indicated that all formulations, except for conventional toothpaste (Sorriso®), showed antimicrobial activity against Gram-positive bacteria and yeasts. The toothpaste containing natural extracts (Parodontax®) was the only product able to inhibit the growth of Pseudomonas aeruginosa. The toothpastes containing chlorhexidine, triclosan or natural extracts presented antimicrobial activity against Gram-positive bacteria and yeasts.

  16. Chemical properties and antioxidant and antimicrobial activities of Slovenian propolis.

    Science.gov (United States)

    Mavri, Ana; Abramovič, Helena; Polak, Tomaž; Bertoncelj, Jasna; Jamnik, Polona; Smole Možina, Sonja; Jeršek, Barbara

    2012-08-01

    The chemical composition as well as the antioxidant and antimicrobial activities of two EtOH extracts of propolis (PEEs) from Slovenia were determined. EtOH was used as extracting solvent at 70 and 96%, providing the extracts PEE70 and PEE96, respectively. The extraction with 70% EtOH was more efficient than that with 96% EtOH, as the PEE70 was richer in total phenolic compounds than the PEE96. The Slovenian propolis was characterized by different phenolic acids and flavonoids. The PEE96 was slightly richer in three specific compounds, i.e., caffeic acid, ferulic acid, and luteolin, while all other substances detected showed higher contents in the PEE70. The PEE70 showed a stronger reducing power and ability to scavenge free radicals and metal ions than the PEE96. Both PEEs were in the main more effective against Gram-positive bacteria than against fungi and Gram-negative bacteria like Salmonella and Escherichia coli, with the exception of Campylobacter. The PEE96 decreased the intracellular oxidation in Saccharomyces cerevisiae in a dose-dependent manner. The antimicrobial activities and antioxidant properties were related to the total phenolic contents. The two PEEs have the potential for use as natural antimicrobial and antioxidant additives in foods.

  17. IN VITRO ANTIMICROBIAL ACTIVITY OF CUSCUTA REFLEXA ROXB.

    Directory of Open Access Journals (Sweden)

    Inamdar Faiyyaz B

    2011-04-01

    Full Text Available Antimicrobial agents are effective in the treatment of infections because of their selective toxicity that is they have the ability to injure or kill an invading microorganism without harming the cells of the host. Cuscuta reflexa Roxb. (Convolvulaceae is parasitic plant. It is used as anthelmintic, carminative, purgative, constipation, aphrodisiac, alterative in different disorder. Ethanolic extract of Cuscuta reflexa Roxb. were prepared by soxhlet extraction method. The qualitative and quantitative, macroscopic, microscopic, phytochemical, physicochemical, analysis of plant has been studied. Antimicrobial activity of stems of cuscuta reflexa Roxb were studied using ethanolic extract against Gram positive bacteria like Bacillus subtilis, staphylococcus aureus and Gram negative bacteria like Escherichia coli, Pseudomonas aeroginosa as well as on some fungal strains like Penicillium citrium, Aspargillus niger using standard (Penicillin. Sterile nutrient agar plates were prepared by using Pour plate & Spread plate method. The ethanolic extracts were poured into the wells of sterile nutrient agar medium using agar cup plate method. The results were analysed by using zone of inhibitions and it was observed that Gram negative and Fungal strains showed more antimicrobial activity as compared to the Gram positive bacteria.

  18. Novel antimicrobial peptides with high anticancer activity and selectivity.

    Directory of Open Access Journals (Sweden)

    Hung-Lun Chu

    Full Text Available We describe a strategy to boost anticancer activity and reduce normal cell toxicity of short antimicrobial peptides by adding positive charge amino acids and non-nature bulky amino acid β-naphthylalanine residues to their termini. Among the designed peptides, K4R2-Nal2-S1 displayed better salt resistance and less toxicity to hRBCs and human fibroblast than Nal2-S1 and K6-Nal2-S1. Fluorescence microscopic studies indicated that the FITC-labeled K4R2-Nal2-S1 preferentially binds cancer cells and causes apoptotic cell death. Moreover, a significant inhibition in human lung tumor growth was observed in the xenograft mice treated with K4R2-Nal2-S1. Our strategy provides new opportunities in the development of highly effective and selective antimicrobial and anticancer peptide-based therapeutics.

  19. Antimicrobial substances produced by coliform strains active against foodborne pathogens.

    Science.gov (United States)

    Fleming, Luana Rocha; Bolzan, Dayana Nascimento; Nascimento, Janaína Dos Santos

    2010-03-01

    In the present study, 31 coliform strains were isolated from salad, cheese, and meat products sold in commercial establishments in Rio de Janeiro city, and were tested for antibiotic resistance and antimicrobial substance production. Thirteen strains (41.9%) were resistant to at least one antibiotic tested, among which one presented resistance to nine different antibiotics. Two strains (6.4%) exhibited inhibitory activity against the indicator strains, Escherichia coli LMIFRJ and Salmonella enterica I. The antimicrobial substances that they produced were sensitive to proteolytic enzymes, suggesting that they might be bacteriocins. The producer strains were identified as Klebsiella ozaenae and Raoultella terrigena. Although they had similar spectrums of action, the bacteriocins were shown to be different. Both of them were able to inhibit E. coli, Klebsiella, Enterobacter, and Salmonella strains, including antibiotic-resistant ones. Our results suggest that these bacteriocins, named klebicin K and raoultellin L, could have potential use against some foodborne pathogens.

  20. Synthesis and Antimicrobial Activity of a Silver-Hydroxyapatite Nanocomposite

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    Marcos Díaz

    2009-01-01

    Full Text Available A silver-hydroxyapatite nanocomposite has been obtained by a colloidal chemical route and subsequent reduction process in H2/Ar atmosphere at 350∘C. This material has been characterized by TEM, XRD, and UV-Visible spectroscopy, showing the silver nanoparticles (∼65 nm supported onto the HA particles (∼130 nm surface without a high degree of agglomeration. The bactericidal effect against common Gram-positive and Gram-negative bacteria has been also investigated. The results indicated a high antimicrobial activity for Staphylococcus aureus, Pneumococcus and Escherichia coli, so this material can be a promising antimicrobial biomaterial for implant and reconstructive surgery applications.

  1. Bis-chalcones and flavones: synthesis and antimicrobial activity.

    Science.gov (United States)

    Husain, Asif; Rashid, Mohd; Mishra, Ravinesh; Kumar, Deepak

    2013-01-01

    A series of bis-chalcones (3a-g) and their flavones derivatives (4a-g) were synthesized and evaluated for their antimicrobial activity. Bis-chalcones were prepared by condensing 1,1'-(4,6-dihydroxy-1,3-phenylene)diethanone (2) with appropriate aryl aldehydes following Claisen-Schmidt reaction conditions. Oxidative cyclization of bis-chalcones (3a-g) in DMSO in the presence of iodine furnished flavones (4a-g). The synthesized compounds were evaluated for their antibacterial and antifungal actions against some selected microbes. The results of antimicrobial evaluation showed that some of the synthesized compounds were good in their antibacterial and antifungal actions.

  2. Spermicidal Activity of the Safe Natural Antimicrobial Peptide Subtilosin

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    Katia E. Sutyak

    2008-01-01

    Full Text Available Bacterial vaginosis (BV, a condition affecting millions of women each year, is primarily caused by the gram-variable organism Gardnerella vaginalis. A number of organisms associated with BV cases have been reported to develop multidrug resistance, leading to the need for alternative therapies. Previously, we reported the antimicrobial peptide subtilosin has proven antimicrobial activity against G. vaginalis, but not against the tested healthy vaginal microbiota of lactobacilli. After conducting tissue sensitivity assays using an ectocervical tissue model, we determined that human cells remained viable after prolonged exposures to partially-purified subtilosin, indicating the compound is safe for human use. Subtilosin was shown to eliminate the motility and forward progression of human spermatozoa in a dose-dependent manner, and can therefore be considered a general spermicidal agent. These results suggest subtilosin would be a valuable component in topical personal care products aimed at contraception and BV prophylaxis and treatment.

  3. Conjugation with Acridines Turns Nuclear Localization Sequence into Highly Active Antimicrobial Peptide

    Directory of Open Access Journals (Sweden)

    Zhang Wei

    2015-12-01

    Full Text Available The emergence of multidrug-resistant bacteria creates an urgent need for alternative antibiotics with new mechanisms of action. In this study, we synthesized a novel type of antimicrobial agent, Acr3-NLS, by conjugating hydrophobic acridines to the N-terminus of a nuclear localization sequence (NLS, a short cationic peptide. To further improve the antimicrobial activity of our agent, dimeric (Acr3-NLS2 was simultaneously synthesized by joining two monomeric Acr3-NLS together via a disulfide linker. Our results show that Acr3-NLS and especially (Acr3-NLS2 display significant antimicrobial activity against gram-negative and gram-positive bacteria compared to that of the NLS. Subsequently, the results derived from the study on the mechanism of action demonstrate that Acr3-NLS and (Acr3-NLS2 can kill bacteria by membrane disruption and DNA binding. The double targets–cell membrane and intracellular DNA–will reduce the risk of bacteria developing resistance to Acr3-NLS and (Acr3-NLS2. Overall, this study provides a novel strategy to design highly effective antimicrobial agents with a dual mode of action for infection treatment.

  4. Active Anti-Microbial Effects of Larch and Pine Wood on Four Bacterial Strains

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    Christina M. Laireiter

    2013-11-01

    Full Text Available Active anti-microbial effects of larch (Larix decidua Mill. and pine (Pinus sylvestris L. wood materials on Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecium, and Bacillus subtilis were tested. The agar-diffusion test, a method used in routine diagnostics, was implemented to detect anti-microbial effects of wooden discs and filter paper discs containing methanol extracts of different wood parts. The results showed that the bark of larch had an inhibitory effect on Staphylococcus aureus, and the heart wood of pine showed a significant anti-microbial effect on the gram-positive bacteria tested (Staphylococcus aureus, Enterococcus faecium, and Bacillus subtilis. These results were confirmed by using methanol-extracts. An anti-microbial activity against Pseudomonas aeruginosa was not found. Anti-bacterial effects of other parts of larch wood and of pine sapwood were also not found. The results of this study showed for the first time that certain parts of wood contain compounds that directly reduce microbial growth. These data are a further demonstration of the positive effects of specific wood species and could promote the usage of wood in hygienically sensitive areas.

  5. Antidiarrhoeal and antimicrobial activity of Calpurnia aurea leaf extract

    Directory of Open Access Journals (Sweden)

    Umer Shemsu

    2013-01-01

    Full Text Available Abstract Background In Ethiopia, Calpurnia aurea is used for the treatment of syphilis, malaria, rabies, diabetes, hypertension, diarrhoea, leishmaniasis, trachoma, elephantiasis, fungal diseases and different swellings. However, despite its traditional usage as an antidiarrhoeal and antimicrobial agent, there is limited or no information regarding its effectiveness and mode of action in diarrhoea which may be caused by Shigella flexneri, Staphylococcus aureus, Escherichia coli and Salmonella typhi. Hence, we evaluated the 80% methanol (MeOH extract of dried and powdered leaves of C. aurea for its antidiarrhoeal and antimicrobial activities. Methods Swiss albino mice of either sex were divided into five groups (five/group: Group I served as control and received vehicle (1% Tween 80 at a dose of 10 ml/kg orally; Group II served as standard and received loperamide at the dose of 3 mg/kg orally; Groups III, IV and V served as test groups and received the 80% MeOH leaf extract of C. aurea at doses of 100, 200 and 400 mg/kg orally, respectively. Diarrhoea was induced by oral administration of 0.5 ml castor oil to each mouse, 1 h after the above treatments. During an observation period of 4 h, time of onset of diarrhea, total number of faecal output (frequency of defecation and weight of faeces excreted by the animals were recorded. Data were analyzed using one way analysis of variance followed by Tukey post test. Antimicrobial activity test was conducted using agar well diffusion assay. Clinical isolates tested were Salmonella typhi, Salmonella paratyphi, Salmonella typhimurium, Shigella species, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli. Results In castor oil induced diarrhea model, the 80% methanol leaf extract of C. aurea at 100, 200 and 400 mg/kg and the standard drug loperamide (3 mg/kg significantly reduced the time of onset of diarrhea, the frequency of defecation (total number of faecal output and weight of faeces. C

  6. The Phytochemical Contents and Antimicrobial Activities of Malaysian Calophyllum Rubiginosum

    Directory of Open Access Journals (Sweden)

    Suhaib I. ALkhamaiseh

    2011-01-01

    Full Text Available Problem statement: Many species of plants in Malaysia are widely used in folk medicine. However, Calophyllum species have been used in traditional medicine for their therapeutic values for many years. Several studies reported that antimicrobial, antifungal, anti-HIV and anti-cancer compounds were isolated from numerous Calophyllum species. Approach: The stem bark was extracted by EtOH, after with it was fractionated with n-Hexane, Dichloromethane (DCM and MeOH by using vacuum liquid chromatography apparatus. Phytochemical contents were examined to evaluate the phinolic, flavonoid and flavonol contents. Also the antimicrobial activity was carried out by using disc diffusion and dilution method to evaluate antimicrobial activity of the crude and the fractions respectively. Six references microbial strains of human pathogens were used for examined the anti microbial activity. The two Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus and two Gram-negative (Pseudomonas aeruginosa, Escherichia coli were used for antibacterial test. Also two fungal strains (Candida albicans and Cryptococcus neoformans were used for antifungal test. Results: Although the C. rubiginosum has phytochemicals as all plants, but it was showed a high content of flavonol in the range of 11.9- 15.2 µg mL−1. The C. rubiginosum fractions were showed no activity against gram negative and fungus. However, the non polar and semi polar fractions were showed a result MIC 12.5 µg mL−1 against B.cereus bacteria. While the MeOH fraction indicated for low or no activity against bacteria and fungus. Conclusion: At last, the optimistic result of this study encourage us to go forward for further studies in the future to isolate the active compound of the stem bark of C. rubiginosum, where it could lead to a new antibiotic, whereas this species never investigated before.

  7. Spectrum and activity of novel antimicrobial peptidomimetics

    DEFF Research Database (Denmark)

    Hein-Kristensen, Line

    Antibiotics have been an effective weapon against bacterial infections for over 50 years. However, bacterial resistance towards conventional antibiotics has increased considerably within the last decades and the number of antibacterial agents available for treating complicated bacterial infection...... design, with a 1:1 ratio between cationic a-amino acids and hydrophobic ß-peptoids, amino acid composition and chirality in the ß-peptoid unit only had a minor influence on antibacterial activity. By using an ATP leakage assay we determined that the mechanism of action of the chimeras...... Concentration (MIC). The findings show that all of the chimeras included in the study have a similar mechanism of action that was independent on bacterial species. However, the study showed that the detailed interaction with the cell membrane may be different, since there were large variations in the amount...... protocol encompassing 500 generations, 10 out of 10 lineages of Escherichia coli developed resistance towards the chimera they had been exposed to. This was the first time resistance was successfully developed towards peptidomimetics, though several studies have reported resistance towards AMPs. Resistance...

  8. Composition and antimicrobial activities of the leaf essential oil of Machilus zuihoensis from Taiwan

    Directory of Open Access Journals (Sweden)

    Chen-Lung Ho

    2012-04-01

    Full Text Available This study investigated the chemical composition, and antimicrobial and anti-wood-decay fungal activities of the essential oil isolated from the leaf of endemic Machilus zuihoensis Hayata, Lauraceae, of Taiwan. The essential oil from the fresh leaves of M. zuihoensis was isolated using hydrodistillation in a Clevenger-type apparatus, and characterized by GC-FID and GC-MS. A total of 104 compounds were identified, representing 100% of the oil. The main components identified were n-dodecanal (23.8% and (E-nerolidol (10.5%. The antimicrobial activity of the oil was tested by the disc diffusion method and micro-broth dilution method against ten microbial species (Bacillus cereus, Staphylococcus aureus, S. epidermidis, Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa, Vibrio parahaemolyticus, Aspergillus niger, and Candida albicans, respectively. The oil exhibited strong growth suppression against Gram-positive bacteria and yeast with inhibition zones of 35~43 mm to MIC values of 125 µg mL-1, respectively. The anti-wood-decay fungal activity of the oil was also evaluated. Results showed that the oil demonstrated excellent activity against four wood-decay-fungi species (Trametes versicolor, Phaneochaete chrysosporium, Phaeolus schweintizii, and Lenzites sulphureu. For the antimicrobial and anti-wooddecay fungal activities of the oil, the active source compounds were determined to be τ-cadinol, β-eudesmol, and n-dodecanal.

  9. Chemical Composition and Antimicrobial Activity of Artemisiatschernieviana Besser from Iran

    Directory of Open Access Journals (Sweden)

    Masoud Kazemi

    2009-01-01

    Full Text Available The oil obtained from hydrodistillation of the aerial parts of Artemisia tschernieviana was analyzed by GC and GC/MS. The main constituents of the 30 identified components were p-cymene (21.3%, β-pinene (17.8%, α-pinene (9.4%, γ-terpinene (9.1%, (Z-cis-ocimene (8.8%, and α-cadinol (8.1%. This species is rich in monoterpenes. Antimicrobial activity was determined against six bacterial strains and one fungal strain. The results show that this oil is active against all the tested strains.

  10. In vitro antimicrobial activity of ethanolic fractions of Cryptolepis sanguinolenta

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    Mills-Robertson Felix C

    2012-06-01

    Full Text Available Abstract Background Following claims that some plants have antimicrobial activities against infectious microbes, the in vitro antimicrobial activities of different solvent fractions of ethanolic extract of Cryptolepis sanguinolenta were evaluated against eight standard bacteria and clinical isolates. Methods The solvent partitioning protocol involving ethanol, petroleum ether, chloroform, ethyl acetate and water, was used to extract various fractions of dried pulverized Cryptolepis sanguinolenta roots. Qualitative phyto-constituents screening was performed on the ethanol extract, chloroform fraction and the water fraction. The Kirby Bauer disk diffusion method was employed to ascertain the antibiogram of the test organisms while the agar diffusion method was used to investigate the antimicrobial properties of the crude plant extracts. The microplate dilution method aided in finding the MICs while the MBCs were obtained by the method of Nester and friends. The SPSS 16.0 version was used to analyze the percentages of inhibitions and bactericidal activities. Results The phytochemical screening revealed the presence of alkaloids, reducing sugars, polyuronides, anthocyanosides and triterpenes. The ethanol extract inhibited 5 out of 8 (62.5% of the standard organisms and 6 out of 8 (75% clinical isolates. The petroleum ether fraction inhibited 4 out of 8 (50% of the standard microbes and 1 out of 8 (12.5% clinical isolates. It was also observed that the chloroform fraction inhibited the growth of all the organisms (100%. Average inhibition zones of 14.0 ± 1.0 mm to 24.67 ± 0.58 mm was seen in the ethyl acetate fraction which halted the growth of 3 (37.5% of the standard organisms. Inhibition of 7 (87.5% of standard strains and 6 (75% of clinical isolates were observed in the water fraction. The chloroform fraction exhibited bactericidal activity against all the test organisms while the remaining fractions showed varying degrees of

  11. ANTIMICROBIAL ACTIVITY OF DIFFERENT THIOSEMICARBAZONE COMPOUNDS AGAINST MICROBIAL PATHOGENS

    Directory of Open Access Journals (Sweden)

    Negi Parul

    2012-05-01

    Full Text Available Thiosemicarbazone belongs to a large group of thiourea derivatives, whose biological activities are a function of parent aldehyde or ketone moiety. They have been evaluated over the last 50 year as antiviral, antibacterial, antifungal, antimalarial, anticancer, leprosy, rheumatism, trypanosomiasis and coccidiodis. Thiosemicarbazones were prepared by simple process in which N4-thiosemicarbazone moiety was replaced by aliphatic, arylic and cyclic amines. Present study reported the anti-microbial activity of different thiosemicarbazone compounds against certain bacterial and fungal pathogens viz. Bacillus cereus, Staphylococcus epidermis, Moraxella cattarhalis, Staph. Saprophyticus, Candida albicans and Aspergillus flavans.

  12. Study of the antimicrobial activity of metal complexes and their ligands through bioassays applied to plant extracts

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    Antonio F. Santos

    2014-06-01

    Full Text Available The appearance of resistant bacteria was found to reduce the efficiency of antimicrobial therapies with the current antibiotics, thereby increasing the need for more efficient drugs for the treatment of infections. Several studies have demonstrated an increase in antimicrobial activity following the interaction of several compounds with metal ions. The present study used a methodology adapted for antimicrobial bioassays using plant extracts, in compliance with the standards of the Clinical and Laboratory Standards Institute against Gram-positive and Gram-negative bacteria. The results obtained were considered appropriate for determining MIC, MBC as for performing antimicrobial sensitivity testing with good efficiency and reproducibility. The bacteriaPseudomonas fluorescens exhibited high sensitivity to the tested compounds, being efficient to evaluate the antibacterial activity. The bioassays with the metal complexes of flavonoid quercetin and Ga(III ions, and synthetic ligand H2bbppd and Cu(II ions showed a greater inhibitory effect than their individual ligands, thus, the addition indicated an increase in the antimicrobial activity after the coordination. Both metal complexes exhibit good antimicrobial performances, such as low minimum inhibitory concentration (MIC ≤ 250 µg/ml, bactericidal effect and a broad activity spectrum, which qualify these compounds as suitable candidates to the next step of drugs fabrication. Nevertheless, further studies on the mechanism of growth inhibition and toxicity are needed, in order to evaluate the potential of therapeutic application.

  13. [Bactericidal activity of sitafloxacin and other new quinolones against antimicrobial resistant Streptococcus pneumoniae].

    Science.gov (United States)

    Kobayashi, Intetsu; Kanayama, Akiko; Hasegawa, Miyuki; Kaneko, Akihiro

    2013-02-01

    We conducted a study assess the bactericidal activity of sitafloxacin (STFX) against Streptococcus pneumoniae isolates recovered from respiratory infections including penicillin-resistant (PRSP) isolates, macrolide resistant isolates possessing mefA and ermB resistance genes and quinolone resistance isolates with mutations in gyrA or gyrA and parC. Each isolate tested was grown in hemosupplemented Mueller-Hinton broth and adjusted to approximately 10(5) CFU/ mL. Isolates were than exposed to a Cmax antimicrobial blood level that would be attained with routine antimicrobial administration and an antimicrobial level that would be expected 4 hours post-Cmax (Cmax 4hr). Bactericidal activity was measured for up to 8 hours. Excluding a subset of S. pneumoniae isolates with mutations in the quinolone resistance determining region (QRDR), all quinolones showed bactericidal activity at Cmax and Cmax 4 hr antimicrobial concentrations for up to 8 hours. Against S. pneumoniae isolates with either gyrA or gyrA and parC mutations, bactericidal activity of STFX was shown for up to 4 to 8 hours following Cmax based on a limit of detection of quinolones tested where adjusted to concentrations corresponding to their MICs, STFX showed the most rapid bactericidal activity against PRSP. This rapid bactericidal activity in PRSP is a key to the effectiveness of STFX. Our findings show that beyond inhibition of bacterial replication by blocking their DNA replication pathway and synthesis of proteins, STFX demonstrated characteristics contributing to greater bactericidal activity compared to GRNX. In conclusion, of the newer quinolones, STFX showed the strongest bactericidal activity against S. pneumoniae isolates with mutations in the QRDR which indicates that it may show the most effective clinical utility among the quinolones in respiratory infections.

  14. Super-SERS-active and highly effective antimicrobial Ag nanodendrites

    Science.gov (United States)

    Li, H. B.; Liu, P.; Liang, Y.; Xiao, J.; Yang, G. W.

    2012-07-01

    We have developed simple and green electrochemistry to synthesize Ag nanostructures with high purity, good crystallinity and smooth surface for applications as super-SERS (surface-enhanced Raman scattering), SERS-active substrates and with highly effective antimicrobial activities. This synthesis takes place in a clean and slow reaction environment without any chemical additives, which ensures an ultrahigh active surface of the as-synthesized Ag nanostructures owing to their purity, good crystallinity and smooth morphology. Using this method, we synthesized nearly perfect Ag nanodendrites (NDs), which exhibit super-SERS sensitivity when they are used to detect the SERS spectra of rhodamine 6G at concentrations as low as 5 × 10-16 M, and have an ultrahigh electromagnetic (EM) enhancement factor of the order of 1013, breaking through the theoretical limit of EM enhancement. Meanwhile, the as-synthesized Ag NDs possess highly effective antimicrobial activities for Escherichia coli, Candida albicans and Staphylococcus aureus, which are over 10 times that of silver nanoparticles. Additionally, the basic physics and chemistry involved in the fabrication of Ag nanostructures are pursued. These investigations show that silver nanostructures with highly active surfaces can make the most of Ag nanostructures functioning as super-SERS-active substrates and multiple antibiotics.

  15. PHYTOCHEMICAL STUDY, ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF EUPHORBIA RESINIFERA L.

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    Houcine Benmehdi

    2013-09-01

    Full Text Available The present study was aimed at detecting the phytochemicals and evaluating the antioxidant and antimicrobial activities of Euphorbia resinifera known for their medicinal properties in folk medicine. Phytochemical screening was carried out on the aerial part of Euphorbia resinifera. The assessment of antifungal activity was performed in terms of percentage of radial growth on solid medium (potatoes dextrose agar PDA against Aspergillus flavus and Penicillium expansum. The antibacterial effect was studied by the agar direct contact method using Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli strains. Then, the antioxidant evaluation of the extracts of alkaloids, flavonoids and methanolic extract was performed by DPPH• free radical scavenging and high performance thin layer chromatography (HPTLC techniques. The phytochemical estimation revealed the presence of alkaloids, flavonoids and saponosides. These phytochemicals were isolated from the plant with yields of 0.7 %, 0.4 % and 0.35 %. HPTLC screening provided qualitatively the antioxidant effect of extracts under study. Furthermore, it was found that the methanolic, flavonoids and alkaloids extracts had a potent DPPH scavenging potency with IC50 values of 0.0086; 0.378 and 1.171 mg/mL, respectively. Finally, the results of antimicrobial activity of the aqueous extract showed a pronounced antifungal activity against the tested strains. The percentage inhibition values were found to be in the range of 64.14 to 85.51 % against Aspergillus flavus and 60.33 to 92.28 % against Penicillium expansum. In contrast, the same extract inhibited only the growth of Escherichia coli bacteria. Further study is recommended to isolate and elucidate the active compounds and to evaluate in vivo their antioxidant and antimicrobial effect.

  16. Synergized antimicrobial activity of eugenol incorporated polyhydroxybutyrate films against food spoilage microorganisms in conjunction with pediocin.

    Science.gov (United States)

    Narayanan, Aarthi; Neera; Mallesha; Ramana, Karna Venkata

    2013-07-01

    Biopolymers and biopreservatives produced by microorganisms play an essential role in food technology. Polyhydroxyalkanoates and bacteriocins produced by bacteria are promising components to safeguard the environment and for food preservation applications. Polyhydroxybutyrate (PHB)-based antimicrobial films were prepared incorporating eugenol, from 10 to 200 μg/g of PHB. The films were evaluated for antimicrobial activity against foodborne pathogens, spoilage bacteria, and fungi such as Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Bacillus cereus, Aspergillus flavus, Aspergillus niger, Penicillium sp., and Rhizopus sp. The synergistic antimicrobial activity of the films in the presence of crude pediocin was also investigated. The broth system containing pediocin (soluble form) as well as antimicrobial PHB film demonstrated an extended lag phase and a significant growth reduction at the end of 24 h against the bacteria. Crude pediocin alone could not elicit antifungal activity, while inhibition of growth and sporulation were observed in the presence of antimicrobial PHB film containing eugenol (80 μg/g) until 7 days in the case of molds, i.e., A. niger, A. flavus, Penicillium sp., and Rhizopus sp. in potato dextrose broth. In the present study, we identified that use of pediocin containing broth in conjunction with eugenol incorporated PHB film could function in synergized form, providing effective hurdle toward food contaminating microorganisms. Furthermore, tensile strength, percent crystallinity, melting point, percent elongation to break, glass transition temperature, and seal strength of the PHB film with and without eugenol incorporation were investigated. The migration of eugenol on exposure to different liquid food simulants was also analyzed using Fourier transform infrared spectroscopy. The study is expected to provide applications for pediocin in conjunction with eugenol containing PHB film to enhance the shelf life of foods in the

  17. Evaluation of antimicrobial activity of selected plant extracts by rapid XTT colorimetry and bacterial enumeration.

    Science.gov (United States)

    Al-Bakri, Amal G; Afifi, Fatma U

    2007-01-01

    The aim of this study was to screen and evaluate the antimicrobial activity of indigenous Jordanian plant extracts, dissolved in dimethylsulfoxide, using the rapid XTT assay and viable count methods. XTT rapid assay was used for the initial screening of antimicrobial activity for the plant extracts. Antimicrobial activity of potentially active plant extracts was further assessed using the "viable plate count" method. Four degrees of antimicrobial activity (high, moderate, weak and inactive) against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, respectively, were recorded. The plant extracts of Hypericum triquetrifolium, Ballota undulata, Ruta chalepensis, Ononis natrix, Paronychia argentea and Marrubium vulgare had shown promising antimicrobial activity. This study showed that while both XTT and viable count methods are comparable when estimating the overall antimicrobial activity of experimental substances, there is no strong linear correlation between the two methods.

  18. Antimicrobial properties and membrane-active mechanism of a potential α-helical antimicrobial derived from cathelicidin PMAP-36.

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    Yinfeng Lv

    Full Text Available Antimicrobial peptides (AMPs, which present in the non-specific immune system of organism, are amongst the most promising candidates for the development of novel antimicrobials. The modification of naturally occurring AMPs based on their residue composition and distribution is a simple and effective strategy for optimization of known AMPs. In this study, a series of truncated and residue-substituted derivatives of antimicrobial peptide PMAP-36 were designed and synthesized. The 24-residue truncated peptide, GI24, displayed antimicrobial activity comparable to the mother peptide PMAP-36 with MICs ranging from 1 to 4 µM, which is lower than the MICs of bee venom melittin. Although GI24 displayed high antimicrobial activity, its hemolytic activity was much lower than melittin, suggesting that GI24 have optimal cell selectivity. In addition, the crucial site of GI24 was identified through single site-mutation. An amino acid with high hydrophobicity at position 23 played an important role in guaranteeing the high antimicrobial activity of GI24. Then, lipid vesicles and whole bacteria were employed to investigate the membrane-active mechanisms. Membrane-simulating experiments showed that GI24 interacted strongly with negatively charged phospholipids and weakly with zwitterionic phospholipids, which corresponded well with the data of its biological activities. Membrane permeabilization and flow cytometry provide the evidence that GI24 killed microbial cells by permeabilizing the cell membrane and damaging membrane integrity. GI24 resulted in greater cell morphological changes and visible pores on cell membrane as determined using scanning electron microscopy (SEM and transmission electron microscope (TEM. Taken together, the peptide GI24 may provide a promising antimicrobial agent for therapeutic applications against the frequently-encountered bacteria.

  19. Selection of enhanced antimicrobial activity posing lactic acid bacteria characterised by (GTG)5-PCR fingerprinting.

    Science.gov (United States)

    Šalomskienė, Joana; Abraitienė, Asta; Jonkuvienė, Dovilė; Mačionienė, Irena; Repečkienė, Jūratė

    2015-07-01

    The aim of the study was a detail evaluation of genetic diversity among the lactic acid bacteria (LAB) strains having an advantage of a starter culture in order to select genotypically diverse strains with enhanced antimicrobial effect on some harmfull and pathogenic microorganisms. Antimicrobial activity of LAB was performed by the agar well diffusion method and was examined against the reference strains and foodborne isolates of Bacillus cereus, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella Typhimurium. Antifungal activity was tested against the foodborne isolates of Candida parapsilosis, Debaromyces hansenii, Kluyveromyces marxianus, Pichia guilliermondii, Yarowia lipolytica, Aspergillus brasiliensis, Aspergillus versicolor, Cladosporium herbarum, Penicillium chrysogenum and Scopulariopsis brevicaulis. A total 40 LAB strains representing Lactobacillus (23 strains), Lactococcus (13 strains) and Streptococcus spp. (4 strains) were characterised by repetitive sequence based polymerase chain reaction fingerprinting which generated highly discriminatory profiles, confirmed the identity and revealed high genotypic heterogeneity among the strains. Many of tested LAB demonstrated strong antimicrobial activity specialised against one or few indicator strains. Twelve LAB strains were superior in suppressing growth of the whole complex of pathogenic bacteria and fungi. These results demonstrated that separate taxonomic units offered different possibilities of selection for novel LAB strains could be used as starter cultures enhancing food preservation.

  20. Investigation of the Antimicrobial Activity of Bacillus licheniformis Strains Isolated from Retail Powdered Infant Milk Formulae.

    Science.gov (United States)

    Alvarez-Ordóñez, Avelino; Begley, Máire; Clifford, Tanya; Deasy, Thérèse; Considine, Kiera; O'Connor, Paula; Ross, R Paul; Hill, Colin

    2014-03-01

    This study investigated the potential antimicrobial activity of ten Bacillus licheniformis strains isolated from retail infant milk formulae against a range of indicator (Lactococcus lactis, Lactobacillus bulgaricus and Listeria innocua) and clinically relevant (Listeria monocytogenes, Staphylococcus aureus, Streptococcus agalactiae, Salmonella Typhimurium and Escherichia coli) microorganisms. Deferred antagonism assays confirmed that all B. licheniformis isolates show antimicrobial activity against the Gram-positive target organisms. PCR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses indicated that four of the B. licheniformis isolates produce the bacteriocin lichenicidin. The remaining six isolates demonstrated a higher antimicrobial potency than lichenicidin-producing strains. Further analyses identified a peptide of ~1,422 Da as the most likely bioactive responsible for the antibacterial activity of these six isolates. N-terminal sequencing of the ~1,422 Da peptide from one strain identified it as ILPEITXIFHD. This peptide shows a high homology to the non-ribosomal peptides bacitracin and subpeptin, known to be produced by Bacillus spp. Subsequent PCR analyses demonstrated that the six B. licheniformis isolates may harbor the genetic machinery needed for the synthesis of a non-ribosomal peptide synthetase similar to those involved in production of subpeptin and bacitracin, which suggests that the ~1,422 Da peptide might be a variant of subpeptin and bacitracin.

  1. All-trans retinoic acid-triggered antimicrobial activity against Mycobacterium tuberculosis is dependent on NPC2.

    Science.gov (United States)

    Wheelwright, Matthew; Kim, Elliot W; Inkeles, Megan S; De Leon, Avelino; Pellegrini, Matteo; Krutzik, Stephan R; Liu, Philip T

    2014-03-01

    A role for vitamin A in host defense against Mycobacterium tuberculosis has been suggested through epidemiological and in vitro studies; however, the mechanism is unclear. In this study, we demonstrate that vitamin A-triggered antimicrobial activity against M. tuberculosis requires expression of NPC2. Comparison of monocytes stimulated with all-trans retinoic acid (ATRA) or 1,25-dihydroxyvitamin D3 (1,25D3), the biologically active forms of vitamin A and vitamin D, respectively, indicates that ATRA and 1,25D3 induce mechanistically distinct antimicrobial activities. Stimulation of primary human monocytes with ATRA did not result in expression of the antimicrobial peptide cathelicidin, which is required for 1,25D3 antimicrobial activity. In contrast, ATRA triggered a reduction in the total cellular cholesterol concentration, whereas 1,25D3 did not. Blocking ATRA-induced cellular cholesterol reduction inhibits antimicrobial activity as well. Bioinformatic analysis of ATRA- and 1,25D3-induced gene profiles suggests that NPC2 is a key gene in ATRA-induced cholesterol regulation. Knockdown experiments demonstrate that ATRA-mediated decrease in total cellular cholesterol content and increase in lysosomal acidification are both dependent upon expression of NPC2. Expression of NPC2 was lower in caseous tuberculosis granulomas and M. tuberculosis-infected monocytes compared with normal lung and uninfected cells, respectively. Loss of NPC2 expression ablated ATRA-induced antimicrobial activity. Taken together, these results suggest that the vitamin A-mediated antimicrobial mechanism against M. tuberculosis requires NPC2-dependent expression and function, indicating a key role for cellular cholesterol regulation in the innate immune response.

  2. Antimicrobial activity of fermented Theobroma cacao pod husk extract.

    Science.gov (United States)

    Santos, R X; Oliveira, D A; Sodré, G A; Gosmann, G; Brendel, M; Pungartnik, C

    2014-09-26

    Theobroma cacao L. contains more than 500 different chemical compounds some of which have been traditionally used for their antioxidant, anti-carcinogenic, immunomodulatory, vasodilatory, analgesic, and antimicrobial activities. Spontaneous aerobic fermentation of cacao husks yields a crude husk extract (CHE) with antimicrobial activity. CHE was fractioned by solvent partition with polar solvent extraction or by silica gel chromatography and a total of 12 sub-fractions were analyzed for chemical composition and bioactivity. CHE was effective against the yeast Saccharomyces cerevisiae and the basidiomycete Moniliophthora perniciosa. Antibacterial activity was determined using 6 strains: Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis (Gram-positive) and Pseudomonas aeruginosa, Klebsiella pneumoniae, and Salmonella choleraesuis (Gram-negative). At doses up to 10 mg/mL, CHE was not effective against the Gram-positive bacteria tested but against medically important P. aeruginosa and S. choleraesuis with a minimum inhibitory concentration (MIC) of 5.0 mg/mL. Sub-fractions varied widely in activity and strongest antibacterial activity was seen with CHE8 against S. choleraesuis (MIC of 1.0 mg/mL) and CHE9 against S. epidermidis (MIC of 2.5 mg/mL). All bioactive CHE fractions contained phenols, steroids, or terpenes, but no saponins. Fraction CHE9 contained flavonoids, phenolics, steroids, and terpenes, amino acids, and alkaloids, while CHE12 had the same compounds but lacked flavonoids.

  3. Antimicrobial activity of methanol extract and fractions from Sarcochlamys pulcherrima

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    Afjal Hussain Mazumder

    2014-03-01

    Full Text Available Antimicrobial evaluation of methanol extract of Sarcochlamys pulcherrima leaf and its hexane, ethyl acetate, n-butanol and water fractions against 31 strains of microorganisms, using agar well, agar disc diffusion, and broth microdilution methods, revealed the activity of methanol extract against Trichophyton mentagrophytes, Candida albicans, Staphylococcus aureus and Escheracia coli (zone of inhibition: 21-40 mm, 200 mg/mL, and MIC: 6.25-50 mg/mL. All fractions also displayed antimicrobial activity (5-20 mg/mL, indeed ethyl acetate and n-butanol fractions showed better activity (MIC: 0.156 to 2.5 mg/mL. C. albicans was most sensitive to n-butanol fraction (15 mm, 2.5 mg/mL. Ethyl acetate and n-butanol fractions were more active against T. mentagrophytes (12 mm at 1.25 mg/mL and S. aureus (ethyl acetate-16 mm, n-butanol-14 mm at 0.625 mg/mL. E. coli was inhibited by n-butanol fraction (13 mm at 2.5 mg/mL. Further, n-butanol fraction (400 µg/disc exhibited promising activity against 14 bacteria, 2 dermatophytes and 2 yeasts strains.

  4. Antimicrobial structure activity relationship of five anthraquinones of emodine type isolated from Vismia laurentii.

    Science.gov (United States)

    Kemegne, Gislaine Aurelie; Mkounga, Pierre; Essia Ngang, Jean Justin; Sado Kamdem, Sylvain Leroy; Nkengfack, Augustin Ephrem

    2017-02-22

    Antimicrobial activity of anthraquinone compounds of emodine type has been reported by many authors. These compounds are found in Vismia laurentii (Clusiaceae), a plant used in traditional pharmacopoeia for treatment of microbial infections among others affections. The continuous identification of new compounds has raised the problem of the relation between the structure and antimicrobial properties. The yeast growth kinetics parameters were not influenced by the pH variation as it was the case for the other tested bacteria. Fungicidal activities were noted for all molecules while only few of them had bactericidal activities, mostly on Gram positive bacteria. Mathematical model establishing a quantitative relationship between physicochemical properties of molecules and their fungicidal activities were obtained for Candida albicans and showed that physicochemical properties impacting on antifungal activity were polarizability, partition coefficient, molecular weight and hydrogen bond acceptor. This work demonstrated that the presence of a long aliphatic chain methoxy group substituted in position two of the emodine structure increased the antibacterial properties of the studied compounds. Moreover this antimicrobial property depends on the pH of the environment, and specifically on the polarizability and number of hydrogen bond acceptors of the compound.

  5. Antimicrobial activity of phenolics and glucosinolate hydrolysis products and their synergy with streptomycin against pathogenic bacteria.

    Science.gov (United States)

    Saavedra, Maria J; Borges, Anabela; Dias, Carla; Aires, Alfredo; Bennett, Richard N; Rosa, Eduardo S; Simões, Manuel

    2010-05-01

    The purpose of the present study was to evaluate the in vitro antibacterial effects of different classes of important and common dietary phytochemicals (5 simple phenolics - tyrosol, gallic acid, caffeic acid, ferulic acid, and chlorogenic acid; chalcone - phloridzin; flavan-3-ol - (-) epicatechin; seco-iridoid - oleuropein glucoside; 3 glucosinolate hydrolysis products - allylisothiocyanate, benzylisothiocyanate and 2-phenylethylisothiocyanate) against Escherichia coli, Pseudomonas aeruginosa, Listeria monocytogenes and Staphylococcus aureus. Another objective of this study was to evaluate the effects of dual combinations of streptomycin with the different phytochemicals on antibacterial activity. A disc diffusion assay was used to evaluate the antibacterial activity of the phytochemicals and 3 standard antibiotics (ciprofloxacin, gentamicin and streptomycin) against the four bacteria. The antimicrobial activity of single compounds and dual combinations (streptomycin-phytochemicals) were quantitatively assessed by measuring the inhibitory halos. The results showed that all of the isothiocyanates had significant antimicrobial activities, while the phenolics were much less efficient. No antimicrobial activity was observed with phloridzin. In general P. aeruginosa was the most sensitive microorganism and L. monocytogenes the most resistant. The application of dual combinations demonstrated synergy between streptomycin and gallic acid, ferulic acid, chlorogenic acid, allylisothiocyanate and 2-phenylethylisothiocyanate against the Gram-negative bacteria. In conclusion, phytochemical products and more specifically the isothiocyanates were effective inhibitors of the in vitro growth of the Gram-negative and Gram-positive pathogenic bacteria. Moreover, they can act synergistically with less efficient antibiotics to control bacterial growth.

  6. Antimicrobial and antipathogenic activity of Fallopia japonica leaves alcoholic extract

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    Ioana-Cristina Marinaş

    2014-08-01

    Full Text Available The aim of the study consists in the investigation of the antimicrobial and antiphatogenic activity of ethanol extracts obtain from F. japonica leaves. Total phenolic content was determined by Folin-Ciocalteu method, while their phenolic composition was specified by HPLC. In vitro antimicrobial activity of various concentrations ranging from 6.25 to 200 μL/mL of alcoholic (ethanol 70% extract of F. japonica were analyzed on different clinical and reference bacterial strains (Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumanii and fungal strains belonging to Candida spp. using agar disk diffusion method and broth dilution method. The anti-pathogenic properties were studied by determining the adhesion capacity of microbial strains to inert substrate. The soluble virulence factors were quantified using specific media with different biochemical substrats for revealing haemolysins, lecithinase, gelatinase, lipase, DN-ase, amylase and iron chelating agents. The antibiogram adapted technique assesseded the synergic effects of F. japonica leaves extracts with the clinical used antibiotics for different bacterial strains. The studied extract showed the best antimicrobial activity against P. aeruginosa (6.25 μL/mL due to phenolic compound identified (epicatechin, rutin and quercetin. In the Gram-positive strains’ case were observed phenotypic changes in the DNA-ase and lechitinase enzymes expression. In the antibioresistance pattern profiling it was observed that F. japonica leaves improved the Kanamycin activity for S. aureus, Colistin for P. aeruginosa and Meropenem for A. baumanii. In this respect, could be assumed that this extract could be used complementarily with antibiotherapy, by inhibiting the specific virulence factors.

  7. Antimicrobial activity of latex silver nanoparticles using Calotropis procera

    Institute of Scientific and Technical Information of China (English)

    Nadia; Hussein; Mohamed; Mady; Ahmed; Ismail; Wael; Moustfa; Abdel-Mageed; Ahmed; Abdelfattah; Mohamed; Shoreit

    2014-01-01

    Objective:To synthesize silver nanoparticles(AgNPs) by green methods using scrum latex of Calotropis procera at 80 ℃ and evaluate them against bacteria,dermatophytes and phytopathogenic fungi comparing with the activity of untreated latex.Methods:The synthesis of AgNPs was performed by mixing 3%latex scrum extract with the same volume of silver nitrate(2 mmol/L) solution in round flask and heating in water bath at80 ℃.Characterization of silver particles were determined using UV-vis spectrophotometer,transmission electron microscopy(TEM),X-ray diffraction and Fourier transform infrared spectroscopy.The antimicrobial activity of the green synthesized AgNPs was determined against bacteria,dermatophytes and phytopathogenic fungi and compared to the crude untreated latex by agar-well diffusion methods.Results:Biosynthesis of latex silver nanoparticles was successfully obtained by green method.The formation of AgNPs has been confirmed by UV-vis,TEM microscopy.X-ray diffraction and Fourier transform infrared spectroscopy.TEM analysis showed that synthesized AgNPs are highly stable spherical shaped particles,well dispersed with a diameter ranged from 4 nm up to 25 nm and an average size of 12.33 nm.AgNPs showed strong antibacterial activity against Gram-negative bacteria(Escherichia coli,Pseudomonas aeruginosa and Serratia sp.) and antifungal activity against Trichophyton rubrum,Candida albicans and Aspergillus terreus.Conclusions:It can be concluded that serum latex of Calotropis pmcera was found to display strong potential for the synthesis of AgNPs as antimicrobial agents through rapid reduction of silver ions(Ag~+ to Ag~0).The green synthesized AgNPs were found to show higher antimicrobial efficacy than crude latex.

  8. Antimicrobial activity of latex silver nanoparticles using Calotropis procera

    Institute of Scientific and Technical Information of China (English)

    Nadia Hussein Mohamed; Mady Ahmed Ismail; Wael Moustfa Abdel-Mageed

    2014-01-01

    Objective: To synthesize silver nanoparticles (AgNPs) by green methods using serum latex of Calotropis procera at 80 °C and evaluate them against bacteria, dermatophytes and phytopathogenic fungi comparing with the activity of untreated latex.Methods:The synthesis of AgNPs was performed by mixing 3% latex serum extract with the same volume of silver nitrate (2 mmol/L) solution in round flask and heating in water bath at 80 °C. Characterization of silver particles were determined using UV-vis spectrophotometer, transmission electron microscopy (TEM), X-ray diffraction and Fourier transform infrared spectroscopy. The antimicrobial activity of the green synthesized AgNPs was determined against bacteria, dermatophytes and phytopathogenic fungi and compared to the crude untreated latex by agar-well diffusion methods.Results:Biosynthesis of latex silver nanoparticles was successfully obtained by green method. The formation of AgNPs has been confirmed by UV-vis, TEM microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. TEM analysis showed that synthesized AgNPs are highly stable spherical shaped particles, well dispersed with a diameter ranged from 4 nm up to 25 nm and an average size of 12.33 nm. AgNPs showed strong antibacterial activity against Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Serratia sp.) and antifungal activity against Trichophyton rubrum, Candida albicans and Aspergillus terreus.Conclusions:It can be concluded that serum latex of Calotropis procera was found to display strong potential for the synthesis of AgNPs as antimicrobial agents through rapid reduction of silver ions (Ag+ to Ag0). The green synthesized AgNPs were found to show higher antimicrobial efficacy than crude latex.

  9. Chemodiversity Associated with Cytotoxicity and Antimicrobial Activity of Piper aduncum var. ossanum.

    Science.gov (United States)

    Gutiérrez, Yamilet; Montes, Rodny; Scull, Ramón; Sánchez, Arturo; Cos, Paul; Monzote, Lianet; Setzer, William N

    2016-12-01

    Chemical analysis, antimicrobial activity and cytotoxic effects of essential oils (EOs) from leaves of Piper aduncum var. ossanum from two localities Bauta (EO-B) and Ceiba (EO-C), Artemisa Province, Cuba, were determined. EOs were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry. EO-B demonstrated higher activity against S. aureus and L. amazonensis; while a lower cytotoxicity on mammalian cells was observed. Both EOs displayed the same activity against Plasmodium falciparum, Trypanosoma cruzi, Trypanosoma brucei, and Leishmania infantum. Both EOs were inactive against Escherichia coli and Candida albicans. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

  10. Amish burn ointment and burdock leaf dressings: assessments of antimicrobial and cytotoxic activities.

    Science.gov (United States)

    Rieman, Mary T; Neely, Alice N; Boyce, Steven T; Kossenjans, William J; Durkee, Paula J; Zembrodt, Jacquelyn M; Puthoff, Barbara K; Kagan, Richard J

    2014-01-01

    Amish burn wound ointment (ABO) contains honey, lanolin, oils, glycerin, bees wax, and other natural additives. Although there are many anecdotal reports that this ointment covered with a burdock leaf (BL) dressing promotes burn wound healing, little scientific testing of this treatment has occurred. The goal of this study was to evaluate in vitro some of the components of this treatment modality for antimicrobial and cytotoxic activities. The ABO was tested for sterility using standard microbiological techniques. Because of the semisolid, lipid-based nature of the salve, the at-use product could not be tested in bioassays. Samples of BL and the dry ingredients (DI) used in the ointment were provided by the Amish vendor. Aqueous extracts of the DI and of the BL were prepared and freeze dried. The freeze-dried extracts were reconstituted, filtered, and tested separately on keratinocyte and fibroblast cell cultures for cytotoxicity (growth inhibition assay) and against a panel of susceptible and resistant microbes for antimicrobial activity (Nathan's agar-well diffusion assay) in a series of concentrations (% wt/vol). Neither DI nor BL extracts demonstrated antimicrobial activity against any of organisms tested. The DI extract inhibited growth of both keratinocytes and fibroblasts at the 0.1% concentration. The 0.1 and 0.03% concentrations of the BL extract were cytotoxic to both keratinocytes and fibroblasts. Although tests for microbial growth from the at-use preparation of the ABO were negative, extracts of the DI and BL did not demonstrate any antimicrobial activity. Additionally, both extracts inhibited the growth of skin cells in vitro at higher concentrations. These results suggest caution in the use of ABO and BL dressings if there is more than a minimal risk of complications from the burn injury.

  11. Antimicrobial activity of tea as affected by the degree of fermentation and manufacturing season.

    Science.gov (United States)

    Chou, C C; Lin, L L; Chung, K T

    1999-05-01

    Bacillus subtilis, Escherichia coli, Proteus vulgaris, Pseudomonas fluorescens, Salmonella sp. and Staphylococcus aureus were used to test the antimicrobial activity of tea flush extract and extracts of various tea products. Among the six test organisms, P. fluorescens was the most sensitive to the extracts, while B. subtilis was the least sensitive. In general, antimicrobial activity decreased when the extents of tea fermentation increased. The antimicrobial activities of tea flush extract and extracts of tea products with different extents of fermentation varied with test organisms. Tea flush and Green tea, the unfermented tea, exerted the strongest antimicrobial activity followed by the partially fermented tea products such as Longjing, Tieh-Kuan-Ying, Paochung, and Oolong teas. On the other hand, Black tea, the completely fermented tea, showed the least antimicrobial activity. It was also noted that extracts of Oolong tea prepared in summer exhibited the strongest antimicrobial activity, followed by those prepared in spring, winter and fall.

  12. Antimicrobial activity of medicinal plant leaf extracts against pathogenic bacteria

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    Atikya Farjana

    2014-09-01

    Full Text Available Objective: To determine antibacterial activity of water, oil and methanol extracts of guava (Psidium guajava, green tea (Camellia sinensis, neem (Azadirachta indica and marigold (Calendula officinalis against different species of bacteria, Pseudomonas spp., Vibrio cholerae, Vibrio parahaemolyticus (V. parahaemolyticus, Klebsiella spp., Escherichia coli, Salmonella spp. and Staphylococcus aureus (S. aureus. Methods: Antibacterial activity of plant extracts was measured by agar well diffusion method. Results: Boiled water extracts of guava leaf showed the largest zone of inhibition (22 mm against V. parahaemolyticus. Water extracts of green tea leaf at boiling and room temperature showed 17.5 mm and 19 mm zone of inhibitions against V. parahaemolyticus and S. aureus, respectively. Boiled water extract of neem leaf showed moderate zone of inhibition against Escherichia coli (10 mm and Klebsiella spp. (11 mm. Water and oil extracts of marigold leaf at both boiling and room temperature did not show any zone of inhibition against any of the tested microorganisms. Methanol extracts of both guava and green tea leaves showed same zone of inhibition against Pseudomonus spp. (18 mm. Methanol extract of neem leaf showed antibacterial acitivity against Klebsiella spp. (16 mm and Vibrio cholerae (14 mm and that of marigold leaf showed antimicrobial activity against S. aureus (18 mm and Klebsiella spp. (12 mm. Conclusions: The results from the study suggest that the leaves of guava, green tea, neem and marigold show anibacterial activity against different bacterial species. They could be used as alternatives to common antimicrobial agents for treatment of bacterial infections.

  13. Benzofuranyl Esters: Synthesis, Crystal Structure Determination, Antimicrobial and Antioxidant Activities

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    C. S. Chidan Kumar

    2015-09-01

    Full Text Available A series of five new 2‐(1‐benzofuran‐2‐yl‐2‐oxoethyl 4-(un/substitutedbenzoates 4(a–e, with the general formula of C8H5O(C=OCH2O(C=OC6H4X, X = H, Cl, CH3, OCH3 or NO2, was synthesized in high purity and good yield under mild conditions. The synthesized products 4(a–e were characterized by FTIR, 1H-, 13C- and 1H-13C HMQC NMR spectroscopic analysis and their 3D structures were confirmed by single-crystal X-ray diffraction studies. These compounds were screened for their antimicrobial and antioxidant activities. The tested compounds showed antimicrobial ability in the order of 4b < 4a < 4c < 4d < 4e and the highest potency with minimum inhibition concentration (MIC value of 125 µg/mL was observed for 4e. The results of antioxidant activities revealed the highest activity for compound 4e (32.62% ± 1.34% in diphenyl-2-picrylhydrazyl (DPPH radical scavenging, 4d (31.01% ± 4.35% in ferric reducing antioxidant power (FRAP assay and 4a (27.11% ± 1.06% in metal chelating (MC activity.

  14. Antimicrobial, antioxidant activities and chemical composition of selected Thai spices

    Directory of Open Access Journals (Sweden)

    Juraithip Wungsintaweekul

    2010-12-01

    Full Text Available Nine volatile oils and six methanol extracts from Ocimum americanum, O. basilicum, O. sanctum, Citrus hystrix,Alpinia galanga, Curcuma zedoaria, Kaempferia parviflora and Zingiber cassumunar were assessed for antimicrobial andantioxidant activities. The volatile oils and extracts were investigated against eight bacteria and three fungi. The resultsillustrated that O. americanum volatile oil exhibited broad spectrum activity against tested bacteria with the MICs ranging1.4-3.6 mg/ml and Candida spp. with the MICs ranging from 0.5-0.6 mg/ml. The O. sanctum volatile oil showed a considerableactivity against only Candida spp. with the MICs ranging from 0.8-1.4 mg/ml. Interestingly, growth of Mycobacteriumphlei was inhibited by the volatiles of O. americanum, C. hystrix peel, and C. zedoaria with MIC of 1.7, 3.5 and 1.2 mg/ml,respectively. For antioxidant activity evaluation, the methanol extracts of C. hystrix (leaf and peel and K. parviflora hadpotent antioxidant activity by the radical-scavenging DPPH method with IC50 of 24.6, 66.3 and 61.5 mg/ml, respectively.GC-MS analysis revealed the typical chemical profiles of the volatile oils. The major component showed the characteristicsof the volatile oils and was probably responsible for the antimicrobial effect.

  15. Phytochemical profiles, antioxidant and antimicrobial activities of three Potentilla species.

    Science.gov (United States)

    Wang, Shan-Shan; Wang, Dong-Mei; Pu, Wen-Jun; Li, Deng-Wu

    2013-11-19

    Extracts from Potentilla species have been applied in traditional medicine and exhibit antioxidant, hypoglycemic, anti-inflammatory, antitumor and anti-ulcerogenic properties, but little has been known about the diversity of phytochemistry and pharmacology on this genus. This study investigated and compared the phytochemical profiles, antioxidant and antimicrobial activities of leaf extracts from three Potentilla species (Potentilla fruticosa, Potentilla glabra and Potentilla parvifolia) in order to discover new resources for lead structures and pharmaceutical products. Chemical composition and content of six phenolic compounds were evaluated and determined by RP-HPLC; Total phenolic and total flavonoid content were determined using Folin-Ciocalteau colourimetric method and sodium borohydride/chloranil-based method (SBC); Antioxidant activities were determined using DPPH, ABTS and FRAP assays; Antimicrobial properties were investigated by agar dilution and mycelial growth rate method. The results showed hyperoside was the predominant phenolic compound in three Potentilla species by RP-HPLC assay, with the content of 8.86 (P. fruticosa), 2.56 (P. glabra) and 2.68 mg/g (P. parvifolia), respectively. The highest content of total identified phenolic compounds (hyperoside, (+)-catechin, caffeic acid, ferulic acid, rutin and ellagic acid) was observed in P. parvifolia (14.17 mg/g), follow by P. fruticosa (10.01 mg/g) and P. glabra (7.01 mg/g). P. fruticosa possessed the highest content of total phenolic (84.93 ± 0.50 mmol gallic acid equivalent/100 g) and total flavonoid (84.14 ± 0.03 mmol quercetin equivalent/100 g), which were in good correlation with its significant DPPHIC50 (16.87 μg/mL), ABTS (2763.48 μmol Trolox equivalent/g) and FRAP (1398.70 μmol Trolox equivalent/g) capacities. Furthermore, the effective methodology to distinguish the different species of Potentilla was also established by chromatographic fingerprint analysis for the first time. The results

  16. Antimicrobial activity of essential oils from Mediterranean aromatic plants against several foodborne and spoilage bacteria.

    Science.gov (United States)

    Silva, Nuno; Alves, Sofia; Gonçalves, Alexandre; Amaral, Joana S; Poeta, Patrícia

    2013-12-01

    The antimicrobial activity of essential oils extracted from a variety of aromatic plants, often used in the Portuguese gastronomy was studied in vitro by the agar diffusion method. The essential oils of thyme, oregano, rosemary, verbena, basil, peppermint, pennyroyal and mint were tested against Gram-positive (Listeria monocytogenes, Clostridium perfringens, Bacillus cereus, Staphylococcus aureus, Enterococcus faecium, Enterococcus faecalis, and Staphylococcus epidermidis) and Gram-negative strains (Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa). For most essential oils examined, S. aureus, was the most susceptible bacteria, while P. aeruginosa showed, in general, least susceptibility. Among the eight essential oils evaluated, thyme, oregano and pennyroyal oils showed the greatest antimicrobial activity, followed by rosemary, peppermint and verbena, while basil and mint showed the weakest antimicrobial activity. Most of the essential oils considered in this study exhibited a significant inhibitory effect. Thyme oil showed a promising inhibitory activity even at low concentration, thus revealing its potential as a natural preservative in food products against several causal agents of foodborne diseases and food spoilage. In general, the results demonstrate that, besides flavoring the food, the use of aromatic herbs in gastronomy can also contribute to a bacteriostatic effect against pathogens.

  17. Fabrication, Characterization, and Antimicrobial Activity, Evaluation of Low Silver Concentrations in Silver-Doped Hydroxyapatite Nanoparticles

    Directory of Open Access Journals (Sweden)

    A. Costescu

    2013-01-01

    Full Text Available The aim of this study was the evaluation of (Ca10-xAgx(PO46(OH2 nanoparticles (Ag:HAp-NPs for their antibacterial and antifungal activity. Resistance to antimicrobial agents by pathogenic bacteria has emerged in the recent years as a major public health problem worldwide. In this paper, we report a comparison of the antimicrobial activity of low concentrations silver-doped hydroxyapatite nanoparticles. The silver-doped nanocrystalline hydroxyapatite powder was synthesized at 100°C in deionised water. The as-prepared Ag:Hap nanoparticles were characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, FT-IR, and FT-Raman spectroscopy. X-ray diffraction (XRD studies demonstrate that powders obtained by coprecipitation at 100°C exhibit the apatite characteristics with good crystal structure, without any new phase or impurities found. FT-IR and FT-Raman spectroscopy revealed the presence of the various vibrational modes corresponding to phosphates and hydroxyl groups and the absence of any band characteristic to silver. The specific microbiological assays demonstrated that Ag:HAp-NPs exhibited antimicrobial features, but interacted differently with the Gram-positive, Gram-negative bacterial and fungal tested strains.

  18. Antimicrobial activity of crude methanolic extracts from Ganoderma lucidum and Trametes versicolor

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2014-11-01

    Full Text Available In this paper the antimicrobial activity of crude methanolic extracts obtained from Ganoderma lucidum and Trametes versicolor were investigated. The antimicrobial activities of the extracts against E. coli, P. aeruginosa, S. epidermis, E. raffinosus, S. cerevisiae and C. albicans were determined by the microbroth dillution method according by EUCAST in 96-well microplates. Microorganisms were obtained from Czech Collection of Microorganisms. Absorbances after and before the experiment were subtracted, converted to binary system and obtained values to Probit analysis were used. Of the two macromycetes extracts tested, not all extracts showed antimicrobial activity in tested MICs range. The highest antimicrobial activity showed the both extracts to Saccharomyces cerevisiae. The less antimicrobial effects had the both macromycetes extracts to Staphylococcus epidermis. Antimicrobial activity of macromycetes methanolic crude extracts to others tested microorganisms showed no effect or used concentration could be higher.

  19. Isolation, identification and antimicrobial activity of propolis-associated fungi.

    Science.gov (United States)

    de Souza, Giovanni Gontijo; Pfenning, Ludwig Heinrich; de Moura, Fabiana; Salgado, Mírian; Takahashi, Jacqueline Aparecida

    2013-01-01

    Propolis is a natural product widely known for its medicinal properties. In this work, fungi present on propolis samples were isolated, identified and tested for the production of antimicrobial metabolites. Twenty-two fungal isolates were obtained, some of which were identified as Alternaria alternata, Aspergillus flavus, Bipolaris hawaiiensis, Fusarium merismoides, Lasiodiplodia theobromae, Penicillium citrinum, Penicillium crustosum, Penicillium janthinellum, Penicillium purpurogenum, Pestalotiopsis palustris, Tetracoccosporium paxianum and Trichoderma koningii. These fungi were grown in liquid media to obtain crude extracts that were evaluated for their antibiotic activity against pathogenic bacteria, yeast and Cladosporium cladosporioides and A. flavus. The most active extract was obtained from L. theobromae (minimum inhibitory concentration = 64 μg/mL against Listeria monocitogenes). Some extracts showed to be more active than the positive control in the inhibition of Staphylococcus aureus and L. monocitogenes. Therefore, propolis is a promising source of fungi, which produces active agents against relevant food poisoning bacteria and crop-associated fungi.

  20. Chemical constituents, antimicrobial and antimalarial activities of Zanthoxylum monophyllum.

    Science.gov (United States)

    Rodríguez-Guzmán, Raquel; Fulks, Laura C Johansmann; Radwan, Mohamed M; Burandt, Charles L; Ross, Samir A

    2011-09-01

    From the leaves and bark of Zanthoxylum monophyllum, a new lignan, 3-methoxy-3',4'-methylenedioxylignan-4,8,9,9'-tetraol (1), has been isolated along with 22 known compounds (2- 23), fifteen of them reported for the first time from Z. monophyllum. Their chemical structures were elucidated using detailed spectroscopic studies and chemical analysis. All compounds were evaluated for antimicrobial and antiprotozoal activities. Alkaloids BIS-[6-(5,6-dihydro-chelerythrinyl)] ether (2) and 6-ethoxy-chelerythrine (4) exhibited strong activity against Aspergillus fumigatus and methicillin-resistant Staphylococcus aureus (MRSA). Compound 4-methoxy-N-methyl-2-quinolone (9) exhibited significant activity against MRSA (IC50 value of 8.0 µM) while compound 5,8,4'-trihydroxy-3,7,3'-trimethoxyflavone (10) showed weak activity against Plasmodium falciparum. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Antioxidant and antimicrobial activities of cinnamic acid derivatives.

    Science.gov (United States)

    Sova, M

    2012-07-01

    Cinnamic acid is an organic acid occurring naturally in plants that has low toxicity and a broad spectrum of biological activities. In the search for novel pharmacologically active compounds, cinnamic acid derivatives are important and promising compounds with high potential for development into drugs. Many cinnamic acid derivatives, especially those with the phenolic hydroxyl group, are well-known antioxidants and are supposed to have several health benefits due to their strong free radical scavenging properties. It is also well known that cinnamic acid has antimicrobial activity. Cinnamic acid derivatives, both isolated from plant material and synthesized, have been reported to have antibacterial, antiviral and antifungal properties. Acids, esters, amides, hydrazides and related derivatives of cinnamic acid with such activities are here reviewed.

  2. Determination of antimicrobial activity of two macro algae extracts

    Directory of Open Access Journals (Sweden)

    Bahar Gümüş

    2016-11-01

    Full Text Available In this study, antimicrobial activity of the possibility of using ethanol extracts obtained from seaweeds Ulva rigida and Gracilaria verrucosa were examined. U. rigida and G. verrucosa were collected from the Coast of Inciraltı (Izmir, Turkey. In the laboratory, the samples were cleaned by rinsing with tap and distilled water, and then dried at 40 °C for 24 hours. Dried and pulverized seaweed samples (10 g were weighed into an amber Erlenmeyer flask, and 200 ml of 95% (v/v ethanol was added. The mixture was shaken and extracted in a water bath shaker at temperatures of 30 °C, 45 °C and 60 °C for 30 min. The extracts were filtered, and ethanol was removed using a rotary evaporator to obtain extracts. Ethanolic extracts of U. rigida and G. verrucosa obtained at different temperatures were evaluated in vitro for antibacterial and antifungal activity on six bacteria (Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Listeria monocytogenes, Escherichia coli and Pseudomonas aeruginosa and two fungi (Aspergillus brasiliensis and Candida albicans using the paper disk agar diffusion method. All extract groups tested were found to have antimicrobial activity against all bacteria and fungi, except for Aspergillus brasiliensis.

  3. Brazilian red propolis: unreported substances, antioxidant and antimicrobial activities.

    Science.gov (United States)

    Righi, Adne A; Alves, Thiago R; Negri, Giuseppina; Marques, Lucas M; Breyer, Henrique; Salatino, Antonio

    2011-10-01

    Chloroform, ethyl acetate and methanol extracts of a sample of red propolis from the state of Alagoas (northeast Brazil) were analyzed by gas chromatography-mass spectrometry and high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Antimicrobial and antioxidant activities were also obtained. The propolis sample contained low content of narigenin-8-C-hexoside, this being the first report of a C-glycoside in propolis. The main constituent found was characterized as 3,4,2',3'-tetrahydroxychalcone. Other important constituents were the chalcone isoliquiritigenin, the isoflavans (3S)-vestitol, (3S)-7-O-methylvestitol, the pterocarpan medicarpin, the phenylpropenes trans-anethol, methyl eugenol, elimicin, methoxyeugenol and cis-asarone, and the triterpenic alcohols lupeol and α- and β- amyrins. The methanol extract exhibited high antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl and β-carotene/linoleic acid assay methods, and antimicrobial activity toward Gram-positive and Gram-negative bacteria. Structures are suggested for new substances never before seen in any kind of propolis. This is the first report of 3,4,2',3'-tetrahydroxychalcone and a flavone C-glycoside in a propolis sample. Copyright © 2011 Society of Chemical Industry.

  4. SYNTHESIS AND ANTIMICROBIAL ACTIVITIES OF NEW PYRAZOLOPYRIDAZINE DERIVATIVES

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    Mahfuz Alam

    2015-03-01

    Full Text Available Several new pryrazolo-pyridazine derivatives (4a-h were synthesized through multi-step synthesis and evaluated for their antimicrobial activities. In the first step, 6-phenyl-2,3,4,5-tetrahydropyridazin-3-one (2 was prepared by reacting 4-(4-chlorophenyl-4-oxobutanoic acid (1 with hydrazine hydrate. Then, aryl-aldehydes were reacted with 2 to furnish pyridazinone derivatives (3a-g. Finally, pyridazinones (3a-h were reacted with hydrazine hydrate to furnish the title compounds (4a-h. The newly synthesized compounds were evaluated for their in vitro antibacterial and antifungal activities against six microbial strains. Compounds 4d, 4e and 4f exhibited significant antibacterial action, whereas compounds 4c and 4d showed potential antifungal activity. Compound 4d, 5-(4-Chlorophenyl-3-(4-fluorophenyl-3,3a,4,7-tetrahydro-2H-pyrazolo[3,4- ]pyridazine, emerged as lead compound having broad spectrum of antimicrobial action.

  5. Antimicrobial activities of essential oil from Artemisiae argyi leaves

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; ZHANG Xue-ke; WU Nan; FU Yu-jie; ZU Yuan-gang

    2006-01-01

    A study was conducted to determine the antimicrobial activities of essential oil from Artemisiae argyi leaves. The sample of the essential oil was analyzed by GC-MS. From 18 compounds representing the oils, Eucalyptole (18.42%), Spathulenol (14.32), 4-Methyl-1-(1-methylethyl)-3-cyclohexen-1-ol (3.10%), 3-Carene (2.64%) appeared as the main components. The screening of antimicro bial activity of the essential oil was evaluated using agar diffusion and broth microdilution methods. Gram-positive bacterial were more sensitive than gram-negative bacterial of the 8 microorganisms, and Staphylococcus aureus ATCC 6538 showed the lowest MIC (0.3125%) and MBC (0.625%). In the disc diffusion assay, Staphylococcus epidermidis ATCC 49134 and Bacillus subtilis ATCC 6633 showed obvious inhibitory activity. Survival curve showed that, 2MIC ofArtemisiae argyi essential oil had a lethal effect on Candida albicans within the first 1 h. Results presented here suggest that the essential oil of Artemisiae argyi leaves possesses antimicrobial properties, and provides scientific foundations for exploition ofArtemisiae argyi.

  6. Phytochemical constituents and antimicrobial activity of leaf extracts of three Amaranthus plant species

    National Research Council Canada - National Science Library

    Z C Maiyo; R M Ngure; J C Matasyoh; R Chepkorir

    2010-01-01

      This study investigated the phytochemical constituents and antimicrobial activity of hexane, ethyl acetate, dichloromethane and methanol leave extracts of Amaranthus hybridus, Amaranthus spinosus...

  7. High antimicrobial activity of VLC isolated fractions from Bifurcaria bifurcata

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    Andre Horta

    2014-06-01

    Full Text Available Infectious diseases continue to be a major public health problem and consequently there is perpetual need for new drugs. In this current study, the antimicrobial potential of isolated fractions from Bifurcaria bifurcata collected in Peniche coast was evaluated. Nine fractions of Bifurcaria bifurcata dichloromethane extracts were produced by Vacuum Liquid Chromatography (VLC using cyclohexane with increasing amounts of 10% of ethyl acetate. All of the VLC fractions were tested against four microorganisms, namely Escherichia coli (ATCC 25922, Staphylococcus aureus (ATCC 12600, Candida albicans (ATCC 10231 and Bacillus subtilis (ATCC 6633. Ampicillin, Chloramphenicol and Amphotericin B was used as positive control. In antimicrobial assays, the F4 fraction showed the best result with IC50 38.28 µg/ml (20.18-72.60 against B. subtilis growth. In same microorganism, the fractions F2 (IC50:183.1 µg/ml (110.5-305.6, F3 (IC50: 71.56 µg/ml (48.10-106.4 and F5 ((IC50: 95.23 µg/ml (60.02-151.1 also inhibited the B. subtilis growth. The fractions F3 (IC50: 184.3 µg/ml (94.82-358.1, F4 (IC50: 113.5 µg/ml (67.76-190.0 and F5 (IC50: 439.6 µg/ml (249.4-774.8 exhibited the highest activity against S. aureus. The fractions F3 and F4 inhibited the C. albicans growth with IC50 of 285.2 µg/ml (146.1-557.1 and 133.6 µg/ml (66.73-267.5, respectively. By contrast, all fractions need more than 1mg/ml to inhibit 50% of E. coli growth. In conclusion, the Bifurcaria bifurcata fractions, collected in Peniche, can be used as source of molecules with a great antimicrobial activity.

  8. Anti-microbial Activity of Urine after Ingestion of Cranberry: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Yee Lean Lee

    2010-01-01

    Full Text Available We explore the anti-microbial activity of urine specimens after the ingestion of a commercial cranberry preparation. Twenty subjects without urinary infection, off antibiotics and all supplements or vitamins were recruited. The study was conducted in two phases: in phase 1, subjects collected the first morning urine prior to ingesting 900 mg of cranberry and then at 2, 4 and 6 h. In phase 2, subjects collected urine on 2 consecutive days: on Day 1 no cranberry was ingested (control specimens, on Day 2, cranberry was ingested. The pH of all urine specimens were adjusted to the same pH as that of the first morning urine specimen. Aliquots of each specimen were independently inoculated with Escherichia coli, Klebsiella pneumoniae or Candida albicans. After incubation, colony forming units/ml (CFU ml−1 in the control specimen was compared with CFU ml−1 in specimens collected 2, 4 and 6 h later. Specimens showing ≥50% reduction in CFU ml−1 were considered as having ‘activity’ against the strains tested. In phase 1, 7/20 (35% subjects had anti-microbial activity against E. coli, 13/20 (65% against K. pneumoniae and 9/20 (45% against C. albicans in specimens collected 2–6 h after ingestion of cranberry. In phase 2, 6/9 (67% of the subjects had activity against K. pneumoniae. This pilot study demonstrates weak anti-microbial activity in urine specimens after ingestion of a single dose of commercial cranberry. Anti-microbial activity was noted only against K. pneumoniae 2–6 h after ingestion of the cranberry preparation.

  9. DETERMINATION OF ANTIMICROBIAL ACTIVITY OF EXTRACTS OF CALENDULA OFFICINALIS FLOWERS

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    P. V. Afanasyeva

    2016-01-01

    Full Text Available Pot marigold (Calendula officinalis L. is one of the most popular medicinal plants in the Russian Federation and abroad. The wide range of pharmacological activity of this medicinal plant is determined by carotenoids, flavonoids, saponins. These biologically active substances give total therapeutic effect of flowers of Calendula officinalis and medicines on base of pot marigold. This paper discusses the results of comparative investigations for a determination of antimicrobial activity of aqueous and aqueous- alcoholic extracts from pot marigold flowers. Detection of the minimum inhibitory concentration (MIC was carried out by using the method of double serial dilutions in broth. The following microorganisms were used as test cultures: Bacillus cereus, Candida albicans, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The study showed that the widest spectrum of antibacterial activity has water extract of pot marigold flowers. As for Pseudomonas aeruginosa the most active medicine is tincture (1:10 with 70% alcohol. As for Escherichia coli the only phytopharmaceutical – water extract of marigold flowers, reveals antimicrobial activity. Against Bacillus cereus the most effective properties was indicated for tincture (1:5 with 70% ethanol and the liquid extract (1:2 with 70% alcohol. In case of Candida albicans, tincture (1:10 with 70% alcohol exhibited the highest activity.

  10. Effect of Fatty Acid Conjugation on Antimicrobial Peptide Activity

    Science.gov (United States)

    2004-12-01

    killing mechanism of antimicrobial peptides makes them an interesting alternative to traditional antibiotics, as target bacteria may be less able...C14-AKK and C16-AKK to within a 7% error are 220 and 16mM respectively. Since amphipathicity is requisite for antimicrobial action KAK is not...Schnaare, 2000: Antimicrobial evaluation of N-alkyl betaines and N-alkyl-N,N-dimethylamine oxides with variations in chain length. Antimicrobial Agents

  11. Quaternary ammonium silane-functionalized, methacrylate resin composition with antimicrobial activities and self-repair potential

    Science.gov (United States)

    Gong, Shi-qiang; Niu, Li-na; Kemp, Lisa K.; Yiu, Cynthia K.Y.; Ryou, Heonjune; Qi, Yi-pin; Blizzard, John D.; Nikonov, Sergey; Brackett, Martha G.; Messer, Regina L.W.; Wu, Christine D.; Mao, Jing; Brister, L. Bryan; Rueggeberg, Frederick A.; Arola, Dwayne D.; Pashley, David H.; Tay, Franklin R.

    2012-01-01

    Design of antimicrobial polymers for enhancing healthcare issues and minimizing environmental problems is an important endeavor with both fundamental and practical implications. Quaternary ammonium silane-functionalized methacrylate (QAMS) represents an example of antimicrobial macromonomers synthesized by a sol-gel chemical route; these compounds possess flexible Si-O-Si bonds. In present work, a partially-hydrolyzed QAMS copolymerized with bis-GMA is introduced. This methacrylate resin was shown to possess desirable mechanical properties with both a high degree of conversion and minimal polymerization shrinkage. Kill-on-contact microbiocidal activities of this resin were demonstrated using single-species biofilms of Streptococcus mutans (ATCC 36558), Actinomyces naeslundii (ATCC 12104) and Candida albicans (ATCC 90028). Improved mechanical properties after hydration provided the proof-of-concept that QAMS-incorporated resin exhibits self-repair potential via water-induced condensation of organic modified silicate (ormosil) phases within the polymerized resin matrix. PMID:22659173

  12. Genetic diversity and some aspects of antimicrobial activity of lactic acid bacteria isolated from goat milk.

    Science.gov (United States)

    Cavicchioli, Valéria Quintana; Dornellas, Wesley Dos Santos; Perin, Luana Martins; Pieri, Fábio Alessandro; Franco, Bernadette Dora Gombossy de Melo; Todorov, Svetoslav Dimitrov; Nero, Luís Augusto

    2015-03-01

    Lactic acid bacteria (LAB, n = 57) were previously obtained from raw goat milk, identified as Lactococcus spp. (n = 24) and Enterococcus spp. (n = 33), and characterized as bacteriocinogenic. Fingerprinting by pulsed field gel electrophoresis (PFGE) demonstrated high genetic diversity, and 30 strains were selected and exhibited strong antimicrobial activity against 46 target strains (LAB, spoilage, and foodborne pathogens). Six strains (Lactococcus lactis: GLc03 and GLc05; and Enterococcus durans: GEn09, GEn12, GEn14, and GEn17) were selected to characterize their bacteriocinogenic features, using Listeria monocytogenes ATCC 7644 as the target. The six strains produced bacteriocins at higher titer when incubated in MRS at 37 °C up to 12 h, when compared to growth at 25 and 30 °C. The produced bacteriocins kept their antimicrobial activity after exposure to 100 °C for 2 h and 121 °C for 20 min; the antimicrobial activity was also observed after treatment at pH 2.0 to 10.0, except for GLc03. L. monocytogenes populations were reduced approximately two logs after treatment with cell-free supernatants from the selected strains. These data show that goat milk can contain a diverse microbiota able to inhibit L. monocytogenes, a common pathogen found in dairy products, and can be potentially employed in biopreservation of food produced under different processing conditions.

  13. Antimicrobial activity of Streptococcus salivarius K12 on bacteria involved in oral malodour.

    Science.gov (United States)

    Masdea, L; Kulik, E M; Hauser-Gerspach, I; Ramseier, A M; Filippi, A; Waltimo, T

    2012-08-01

    To investigate the antimicrobial activity of the bacteriocin-producing strain Streptococcus salivarius K12 against several bacteria involved in halitosis. The inhibitory activity of S. salivarius K12 against Solobacterium moorei CCUG39336, four clinical S. moorei isolates, Atopobium parvulum ATCC33793 and Eubacterium sulci ATCC35585 was examined by a deferred antagonism test. Eubacterium saburreum ATCC33271 and Parvimonas micra ATCC33270, which have been tested in previous studies, served as positive controls, and the Gram-negative strain Bacteroides fragilis ZIB2800 served as a negative control. Additionally, the occurrence of resistance in S. moorei CCUG39336 to S. salivarius K12 was analysed by either direct plating or by passage of S. moorei CCUG39336 on chloroform-inactived S. salivarius K12-containing agar plates. S. salivarius K12 suppressed the growth of all Gram-positive bacteria tested, but the extent to which the bacteria were inhibited varied. E. sulci ATCC35585 was the most sensitive strain, while all five S. moorei isolates were inhibited to a lesser extent. Natural resistance seems to be very low in S. moorei CCUG39336, and there was only a slight decrease in sensitivity after exposure to S. salivarius K12 over 10 passages. Our studies demonstrate that S. salivarius K12 has antimicrobial activity against bacteria involved in halitosis. This strain might be an interesting and valuable candidate for the development of an antimicrobial therapy for halitosis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Antioxidant and antimicrobial activities of the essential oil and solvent extracts of Mentha pulegium L.

    Directory of Open Access Journals (Sweden)

    Palić Ivan R.

    2015-01-01

    Full Text Available We report the total phenolic (TPC; expressed as gallic acid equivalents, GAE, per milligram of dry extract weight and the total flavonoid contents (TFC; expressed as quercetin equivalents, QE, per milligram of dry extract weight and antimicrobial and antioxidant activities of the essential oil and hexane, diethyl ether, ethyl acetate and methanol extracts of Mentha pulegium L. (Lamiaceae collected in Serbia. The total phenolic content was in the range of 129.43-388.29 μg GAE/mg, while TFC ranged from 57.81 to 160.94 QE/mg; the highest TPC and TFC were found in the methanol extract. The antimicrobial activity (against five bacteria and two fungi species of the essential oil and solvent extracts was assessed using disc-diffusion method. However, the studied samples demonstrated a poor antimicrobial potential. The antioxidant activity was screened using five different tests: 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay (DPPH, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid radical cation decolorization assay (ABTS, total reducing power (TRP, ferric reducing antioxidant power (FRAP and cupric reducing antioxidant capacity assay (CUPRAC; the methanol extract showed the strongest antioxidant potential. The results of the different antioxidant assays were correlated mutually and with the total flavonoid and total phenolic contents (regression analysis and agglomerative hierarchical clustering. [Projekat Ministarstva nauke Republike Srbije, br. 172047

  15. In vitro antimicrobial activity of pistachio (Pistacia vera L.) polyphenols.

    Science.gov (United States)

    Bisignano, Carlo; Filocamo, Angela; Faulks, Richard M; Mandalari, Giuseppina

    2013-04-01

    We investigated the antimicrobial properties of polyphenol-rich fractions derived from raw shelled and roasted salted pistachios. American Type Culture Collection (ATCC), food and clinical isolates, of Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Pseudomonas mirabilis), Gram-positive bacteria (Listeria monocytogenes, Enterococcus hirae, Enterococcus faecium, Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus aureus), the yeasts Candida albicans and Candida parapsilosis and the fungus Aspergillus niger were used. Pistachio extracts were active against Gram-positive bacteria with a bactericidal effect observed against L. monocytogenes (ATCC strains and food isolates), S. aureus and MRSA clinical isolates. Extracts from raw shelled pistachios were more active than those from roasted salted pistachios. The bactericidal activity of pistachio extracts could be used to help control the growth of some microorganisms in foods to improve safety and may find application as a topical treatment for S. aureus.

  16. SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF DICHOTOMIN A ANALOGS

    Directory of Open Access Journals (Sweden)

    Himaja Malipeddi

    2010-09-01

    Full Text Available A solution phase peptide synthesis was employed to synthesize Dichotomin A analogs. The N, O-dimethylation on Tyrosine and configurational change of L- to D- on Valine was made on Dichotomin A to derive the compounds 1 Cyclo-L-[Gly-Thr-Phe-Leu-(N-CH3, O-CH3 Tyr-Val] and 2 Cyclo-L-[Gly-Thr-Phe-Leu-(N-CH3,O-CH3Tyr-D-Val]. The structure of these compounds was confirmed by IR, 1H NMR, and FABMASS. The synthesized compounds were tested for their biological activities against bacterial and fungal organisms and were found to be active. Compound (2 carrying D-valine unit have shown more antimicrobial activity than the compound carrying L-valine unit.

  17. Synthesis, Characterization and antimicrobial activity of Cyanopyridine derivatives with Vanillin.

    Directory of Open Access Journals (Sweden)

    K. N. Borkhataria

    2014-02-01

    Full Text Available Cyanopyridines play a vital role owing to their range of biological and physiological activities. In the light of these biological activities and variety of industrial applications, some new of 6-Aryl-4-[4’-(p-chlorobenzyloxy-3’-methoxyphenyl]-2-methoxy-3-cyanopyridines (1a-l & 6-Aryl-4-[4’-(p-chlorobenzyloxy-3’-methoxyphenyl]-2-ethoxy-3-cyanopyridine (2a-l have been prepared, by the cyclocondensation of 1-Aryl-3-[4’-(p-chlorobenzyloxy-3’-methoxyphenyl]-propenones type (I with malononitrile in presence of Sodiummethoxide & Sodiumethoxide. All the prepared compounds were characterized by their spectral (I.R., N.M.R. ,Mass data and screened for their antimicrobial activities.

  18. Antimicrobial activity of Uncaria tomentosa against oral human pathogens.

    Science.gov (United States)

    Ccahuana-Vasquez, Renzo Alberto; Santos, Silvana Soléo Ferreira dos; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

    2007-01-01

    Uncaria tomentosa is considered a medicinal plant used over centuries by the peruvian population as an alternative treatment for several diseases. Many microorganisms usually inhabit the human oral cavity and under certain conditions can become etiologic agents of diseases. The aim of the present study was to evaluate the antimicrobial activity of different concentrations of Uncaria tomentosa on different strains of microorganisms isolated from the human oral cavity. Micropulverized Uncaria tomentosa was tested in vitro to determine the minimum inhibitory concentration (MIC) on selected microbial strains. The tested strains were oral clinical isolates of Streptococcus mutans, Staphylococcus spp., Candida albicans, Enterobacteriaceae and Pseudomonas aeruginosa. The tested concentrations of Uncaria tomentosa ranged from 0.25-5% in Müeller-Hinton agar. Three percent Uncaria tomentosa inhibited 8% of Enterobacteriaceae isolates, 52% of S. mutans and 96% of Staphylococcus spp. The tested concentrations did not present inhibitory effect on P. aeruginosa and C. albicans. It could be concluded that micropulverized Uncaria tomentosa presented antimicrobial activity on Enterobacteriaceae, S. mutans and Staphylococcus spp. isolates.

  19. Synthesis, characteristics and antimicrobial activity of ZnO nanoparticles

    Science.gov (United States)

    Janaki, A. Chinnammal; Sailatha, E.; Gunasekaran, S.

    2015-06-01

    The utilization of various plant resources for the bio synthesis of metallic nano particles is called green technology and it does not utilize any harmful protocols. Present study focuses on the green synthesis of ZnO nano particles by Zinc Carbonate and utilizing the bio-components of powder extract of dry ginger rhizome (Zingiber officinale). The ZnO nano crystallites of average size range of 23-26 nm have been synthesized by rapid, simple and eco friendly method. Zinc oxide nano particles were characterized by using X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray spectroscopy (EDX). FTIR spectra confirmed the adsorption of surfactant molecules at the surface of ZnO nanoparticles and the presence of ZnO bonding. Antimicrobial activity of ZnO nano particles was done by well diffusion method against pathogenic organisms like Klebsiella pneumonia, Staphylococcus aureus and Candida albicans and Penicillium notatum. It is observed that the ZnO synthesized in the process has the efficient antimicrobial activity.

  20. Synthesis, DNA interaction and antimicrobial activities of three rimantadine analogues

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bing-Mi; Zhang, Jun [Department of Pharmacy, Liaoning University, Shenyang 110036 (China); Wang, Xin, E-mail: wangxinlnu@163.com [Department of Pharmacy, Liaoning University, Shenyang 110036 (China); Zhang, Li-Ping; Liu, Yang [Department of Pharmacy, Liaoning University, Shenyang 110036 (China); Niu, Hua-Ying [Jinan Dachpharm Development Co., Ltd., Jinan 250100 (China); Liu, Bin, E-mail: liubinzehao@163.com [Department of Pharmacy, Liaoning University, Shenyang 110036 (China)

    2015-03-15

    The interactions of three rimantadine analogues (RAs) with calf thymus deoxyribonucleic acid (ct-DNA) in buffer solution (pH 7.4) were investigated using berberine (BR) as a probe by various methods. Fluorescence studies revealed that the RAs interacted with DNA in vitro and the quenchings were all static. Furthermore, the binding modes of these compounds to DNA were disclosed as groove binding supported by absorption spectroscopy, viscosity measurement and denatured DNA experiment. The antimicrobial activities of the RAs were also evaluated in Staphylococcus aureus and Escherichia coli, and they all exhibited good bacteriostasic effects. The results might provide an important reference for investigation of the molecular mechanism associated with the DNA binding of the RAs. - Highlights: • Three rimantadine analogues were synthesized. • The RAs effectively quenched the intrinsic fluorescence of DNA via a static combination. • These analogues can bind to DNA via groove binding mode. • The antimicrobial activities of three analogues were also evaluated by the disk diffusion method.

  1. Synthesis, characteristics and antimicrobial activity of ZnO nanoparticles.

    Science.gov (United States)

    Janaki, A Chinnammal; Sailatha, E; Gunasekaran, S

    2015-06-05

    The utilization of various plant resources for the bio synthesis of metallic nano particles is called green technology and it does not utilize any harmful protocols. Present study focuses on the green synthesis of ZnO nano particles by Zinc Carbonate and utilizing the bio-components of powder extract of dry ginger rhizome (Zingiber officinale). The ZnO nano crystallites of average size range of 23-26 nm have been synthesized by rapid, simple and eco friendly method. Zinc oxide nano particles were characterized by using X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-ray spectroscopy (EDX). FTIR spectra confirmed the adsorption of surfactant molecules at the surface of ZnO nanoparticles and the presence of ZnO bonding. Antimicrobial activity of ZnO nano particles was done by well diffusion method against pathogenic organisms like Klebsiella pneumonia, Staphylococcus aureus and Candida albicans and Penicillium notatum. It is observed that the ZnO synthesized in the process has the efficient antimicrobial activity.

  2. Antioxidant and antimicrobial activities of branches extracts of five Juniperus species from Turkey.

    Science.gov (United States)

    Taviano, Maria Fernanda; Marino, Andreana; Trovato, Ada; Bellinghieri, Valentina; La Barbera, Tommaso Massimo; Güvenç, Ayşegül; Hürkul, Muhammed Mesud; Pasquale, Rita De; Miceli, Natalizia

    2011-10-01

    Several Juniperus species (Cupressaceae) are utilized in folk medicine in the treatment of infections and skin diseases. This work was designed to evaluate the antioxidant and antimicrobial potential of methanol and water branches extracts of Juniperus species from Turkey: Juniperus communis L. var. communis (Jcc), Juniperus communis L. var. saxatilis Pall. (Jcs), Juniperus drupacea Labill. (Jd), Juniperus oxycedrus L. subsp. oxycedrus (Joo), Juniperus oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom). Total phenolics, total flavonoids and condensed tannins were spectrophotometrically determined. The antioxidant properties were examined using different in vitro systems. The toxicity was assayed by Artemia salina lethality test. The antimicrobial potential against bacteria and yeasts was evaluated using minimum inhibitory concentration and minimum bactericidal concentration (MIC/MBC) measurements. The effect on bacteria biofilms was tested by microtiter plate assay. Both in the DPPH (1,1-diphenyl-2-picrylhydrazyl) and TBA (thiobarbituric acid) test Jom resulted the most active (IC(50) = 0.034 ± 0.002 mg/mL and 0.287 ± 0.166 µg/mL). Joo exhibited the highest reducing power (1.78 ± 0.04 ASE/mL) and Fe(2+) chelating activity (IC(50) = 0.537 ± 0.006 mg/mL). A positive correlation between primary antioxidant activity and phenolic content was found. The extracts were potentially non-toxic against Artemia salina. They showed the best antimicrobial (MIC = 4.88-30.10 µg/mL) and anti-biofilm activity (60-84%) against S. aureus. The results give a scientific basis to the traditional utilization of these Juniperus species, also demonstrating their potential as sources of natural antioxidant and antimicrobial compounds.

  3. A new effective assay to detect antimicrobial activity of filamentous fungi.

    Science.gov (United States)

    Pereira, Eric; Santos, Ana; Reis, Francisca; Tavares, Rui M; Baptista, Paula; Lino-Neto, Teresa; Almeida-Aguiar, Cristina

    2013-01-15

    The search for new antimicrobial compounds and the optimization of production methods turn the use of antimicrobial susceptibility tests a routine. The most frequently used methods are based on agar diffusion assays or on dilution in agar or broth. For filamentous fungi, the most common antimicrobial activity detection methods comprise the co-culture of two filamentous fungal strains or the use of fungal extracts to test against single-cell microorganisms. Here we report a rapid, effective and reproducible assay to detect fungal antimicrobial activity against single-cell microorganisms. This method allows an easy way of performing a fast antimicrobial screening of actively growing fungi directly against yeast. Because it makes use of an actively growing mycelium, this bioassay also provides a way for studying the production dynamics of antimicrobial compounds by filamentous fungi. The proposed assay is less time consuming and introduces the innovation of allowing the direct detection of fungal antimicrobial properties against single cell microorganisms without the prior isolation of the active substance(s). This is particularly useful when performing large screenings for fungal antimicrobial activity. With this bioassay, antimicrobial activity of Hypholoma fasciculare against yeast species was observed for the first time.

  4. Antimicrobial Activity of neo-Clerodane Diterpenoids isolated from Lamiaceae Species against Pathogenic and Food Spoilage Microorganisms.

    Science.gov (United States)

    Bozov, Petko; Girova, Tania; Prisadova, Natalia; Hristova, Yana; Gochev, Velizar

    2015-11-01

    Antimicrobial activity of nineteen neo-clerodane diterpenoids, isolated from the acetone extracts of the aerial parts of Scutellaria and Salvia species (Lamiaceae) were tested against thirteen strains belonging to nine different species of pathogenic and food spoilage bacteria Aeromonas hydrophila, Bacillus cereus, Escherichia coli, Listeria monocytogenes, Proteus vulgaris, Pseudomonas aeruginosa, Pseudomonas fluorescens, Salmonella abony and Staphylococcus aureus as well as against two yeast strains belonging to species Candida albicans. Seven of the evaluated compounds scutalpin A, scutalpin E, scutalpin F, salviarin, splenolide A, splenolide B and splendidin demonstrated antimicrobial activity against used test microbial strains, the rest of the compounds were inactive within the studied concentration range. Among all of the tested compounds the highest antimicrobial activity was detected for scutalpin A against Staphylococcus aureus (MIC 25 µg/mL).

  5. Antimicrobial Activity of Some Essential Oils-Present Status and Future Perspectives.

    Science.gov (United States)

    Chouhan, Sonam; Sharma, Kanika; Guleria, Sanjay

    2017-08-08

    Extensive documentation on the antimicrobial properties of essential oils and their constituents has been carried out by several workers. Although the mechanism of action of a few essential oil components has been elucidated in many pioneering works in the past, detailed knowledge of most of the compounds and their mechanism of action is still lacking. This knowledge is particularly important for the determination of the effect of essential oils on different microorganisms, how they work in combination with other antimicrobial compounds, and their interaction with food matrix components. Also, recent studies have demonstrated that nanoparticles (NPs) functionalized with essential oils have significant antimicrobial potential against multidrug- resistant pathogens due to an increase in chemical stability and solubility, decreased rapid evaporation and minimized degradation of active essential oil components. The application of encapsulated essential oils also supports their controlled and sustained release, which enhances their bioavailability and efficacy against multidrug-resistant pathogens. In the recent years, due to increasingly negative consumer perceptions of synthetic preservatives, interest in essential oils and their application in food preservation has been amplified. Moreover, the development of resistance to different antimicrobial agents by bacteria, fungi, viruses, parasites, etc. is a great challenge to the medical field for treating the infections caused by them, and hence, there is a pressing need to look for new and novel antimicrobials. To overcome these problems, nano-encapsulation of essential oils and exploiting the synergies between essential oils, constituents of essential oils, and antibiotics along with essential oils have been recommended as an answer to this problem. However, less is known about the interactions that lead to additive, synergistic, or antagonistic effects. A contributing role of this knowledge could be the design of new

  6. Antimicrobial Activity of Some Essential Oils—Present Status and Future Perspectives

    Science.gov (United States)

    Chouhan, Sonam; Sharma, Kanika

    2017-01-01

    Extensive documentation on the antimicrobial properties of essential oils and their constituents has been carried out by several workers. Although the mechanism of action of a few essential oil components has been elucidated in many pioneering works in the past, detailed knowledge of most of the compounds and their mechanism of action is still lacking. This knowledge is particularly important for the determination of the effect of essential oils on different microorganisms, how they work in combination with other antimicrobial compounds, and their interaction with food matrix components. Also, recent studies have demonstrated that nanoparticles (NPs) functionalized with essential oils have significant antimicrobial potential against multidrug- resistant pathogens due to an increase in chemical stability and solubility, decreased rapid evaporation and minimized degradation of active essential oil components. The application of encapsulated essential oils also supports their controlled and sustained release, which enhances their bioavailability and efficacy against multidrug-resistant pathogens. In the recent years, due to increasingly negative consumer perceptions of synthetic preservatives, interest in essential oils and their application in food preservation has been amplified. Moreover, the development of resistance to different antimicrobial agents by bacteria, fungi, viruses, parasites, etc. is a great challenge to the medical field for treating the infections caused by them, and hence, there is a pressing need to look for new and novel antimicrobials. To overcome these problems, nano-encapsulation of essential oils and exploiting the synergies between essential oils, constituents of essential oils, and antibiotics along with essential oils have been recommended as an answer to this problem. However, less is known about the interactions that lead to additive, synergistic, or antagonistic effects. A contributing role of this knowledge could be the design of new

  7. Selective antimicrobial activity and mode of action of adepantins, glycine-rich peptide antibiotics based on anuran antimicrobial peptide sequences.

    Science.gov (United States)

    Ilić, Nada; Novković, Mario; Guida, Filomena; Xhindoli, Daniela; Benincasa, Monica; Tossi, Alessandro; Juretić, Davor

    2013-03-01

    A challenge when designing membrane-active peptide antibiotics with therapeutic potential is how to ensure a useful antibacterial activity whilst avoiding unacceptable cytotoxicity for host cells. Understanding their mode of interaction with membranes and the reasons underlying their ability to distinguish between bacterial and eukaryotic cytoplasmic cells is crucial for any rational attempt to improve this selectivity. We have approached this problem by analysing natural helical antimicrobial peptides of anuran origin, using a structure-activity database to determine an antimicrobial selectivity index (SI) relating the minimal inhibitory concentration against Escherichia coli to the haemolytic activity (SI=HC(50)/MIC). A parameter that correlated strongly with SI, derived from the lengthwise asymmetry of the peptides' hydrophobicity (sequence moment), was then used in the "Designer" algorithm to propose novel, highly selective peptides. Amongst these are the 'adepantins', peptides rich in glycines and lysines that are highly selective for Gram-negative bacteria, have an exceptionally low haemolytic activity, and are less than 50% homologous to any other natural or synthetic antimicrobial peptide. In particular, they showed a very high SI for E. coli (up to 400) whilst maintaining an antimicrobial activity in the 0.5-4μM range. Experiments with monomeric, dimeric and fluorescently labelled versions of the adepantins, using different bacterial strains, host cells and model membrane systems provided insight into their mechanism of action.

  8. Antimicrobial activity of Hypericum annulatum moris and Hypericum elegans stephan ex willd. essential oils from Serbia

    Directory of Open Access Journals (Sweden)

    Đorđević Aleksandra S.

    2013-01-01

    Full Text Available The in vitro antimicrobial activity of Hypericum annulatum and Hypericum elegans essential oils was evaluated against a panel of standardized bacteria and fungi using broth microdilution assay. Both essential oils showed antimicrobial activity against all the tested microorganisms. Hypericum annulatum essential oil showed better antibacterial than antifungal activity, being more effective against Pseudomonas aeruginosa and Escherichia coli while H. elegans essential oil showed no significant difference between antibacterial and antifungal activity. Antimicrobial testing of α-pinene, β-pinene and β-myrcene compounds was also performed. All the compounds were active against all the tested microorganisms, however, based on the MIC, MBC and MFC values, none of these compounds could be thought of as the main bearer of the oils’ antimicrobial activity. This is the first report regarding the antimicrobial activity of the essential oils of the two Hypericum species.

  9. Insights into Animal and Plant Lectins with Antimicrobial Activities

    Directory of Open Access Journals (Sweden)

    Renata de Oliveira Dias

    2015-01-01

    Full Text Available Lectins are multivalent proteins with the ability to recognize and bind diverse carbohydrate structures. The glyco -binding and diverse molecular structures observed in these protein classes make them a large and heterogeneous group with a wide range of biological activities in microorganisms, animals and plants. Lectins from plants and animals are commonly used in direct defense against pathogens and in immune regulation. This review focuses on sources of animal and plant lectins, describing their functional classification and tridimensional structures, relating these properties with biotechnological purposes, including antimicrobial activities. In summary, this work focuses on structural-functional elucidation of diverse lectin groups, shedding some light on host-pathogen interactions; it also examines their emergence as biotechnological tools through gene manipulation and development of new drugs.

  10. Antimicrobial activity of extracts from Tamarindus indica L. leaves.

    Science.gov (United States)

    Escalona-Arranz, Julio César; Péres-Roses, Renato; Urdaneta-Laffita, Imilci; Camacho-Pozo, Miladis Isabel; Rodríguez-Amado, Jesús; Licea-Jiménez, Irina

    2010-07-01

    Tamarindus indica L. leaves are reported worldwide as antibacterial and antifungal agents; however, this observation is not completely accurate in the case of Cuba. In this article, decoctions from fresh and sun dried leaves, as well as fluid extracts prepared with 30 and 70% ethanol-water and the pure essential oil from tamarind leaves were microbiologically tested against Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Pseudomona aeruginosa and Candida albicans. Aqueous and fluid extracts were previously characterized by spectrophotometric determination of their total phenols and flavonoids, while the essential oil was chemically evaluated by gas chromatography/mass spectroscopy (GC/MS). Experimental data suggest phenols as active compounds against B. subtilis cultures, but not against other microorganisms. On the other hand, the essential oil exhibited a good antimicrobial spectrum when pure, but its relative low concentrations in common folk preparations do not allow for any good activity in these extracts.

  11. Antimicrobial Activity and Chemical Composition of Albanian Oregano

    Directory of Open Access Journals (Sweden)

    EDLIRA NEZA

    2015-12-01

    Full Text Available ATCC 25922, Staphylococcus aureus ATCC 6538, Pseudomonas spp, Candida albicans ATCC 10231, Listeria monocytogenes ATCC 19111 and Salmonella typhimurium ATCC 14028. Antimicrobial activity of oregano essential oil was also tested against: E. coli, P. aeruginosa, S. aureus and C. albicans. Only oregano essential oil was active against microorganisms selected. Essential oil of oregano was analysed by GC-MS. Eighteen components were identified representing 99.48 % of the oil. Monoterpenes phenols and derivatives (borneol, 4-terpineol, carvacrol methyl ether, thymoquinone, thymol, carvacrol represented 74.66 % of essential oil. Carvacrol, p-cymene, thymol and γ-terpinene were the main components. Sesquiterpenes such as trans-caryophyllene, α-humulene, β-bisabolene, δ- Cadinene, caryophyllene oxide were also found.

  12. Synthesis and antimicrobial activity of monodisperse copper nanoparticles.

    Science.gov (United States)

    Kruk, Tomasz; Szczepanowicz, Krzysztof; Stefańska, Joanna; Socha, Robert P; Warszyński, Piotr

    2015-04-01

    Metallic monodisperse copper nanoparticles at a relatively high concentration (300 ppm CuNPs) have been synthesized by the reduction of copper salt with hydrazine in the aqueous SDS solution. The average particles size and the distribution size were characterized by Dynamic Light Scattering (DLS), Nanosight-Nanoparticle Tracking Analysis (NTA). The morphology and structure of nanoparticles were investigated using Scanning Electron Microscopy (SEM). The chemical composition of the copper nanoparticles was determined by X-ray Photoelectron Spectroscopy (XPS). Monodisperse copper nanoparticles with average diameter 50 nm were received. UV/vis absorption spectra confirmed the formation of the nanoparticles with the characteristic peak 550 nm. The antimicrobial studies showed that the copper nanoparticles had high activity against Gram-positive bacteria, standard and clinical strains, including methicillin-resistant Staphylococcus aureus, comparable to silver nanoparticles and some antibiotics. They also exhibited antifungal activity against Candida species. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Semisynthetic Modification of Cedrelone and its Antimicrobial Activity

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    P. Malairajana

    2012-12-01

    Full Text Available Cedrelone was isolated from Toona ciliata heart wood and the compound was modified with various chemical reagents and the resultant product was characterized by IR, 1H NMR, 13C NMR and Mass spectra. The synthesized compounds were screened for antimicrobial activities and the zone of inhibition was ascertained by disc diffusion method. The microorganisms selected for the study was Gram positive organisms such as a Staphylococcus aureus (ATCC 9144, b Staphylococcus epidermitis (ATCC 155, c Bacillus subtilis (ATCC 6633, d Bacillus cereus (ATCC 11778, e Micrococcus luteus (ATCC 46789 and Gram negative organisms a Escherichia coli (ATCC 25922, b Pseudomonas aeruginosa (ATCC 9027. Fungi organism a Candida albicans (ATCC 1091, b Aspergillus niger (ATCC 6275. Cedrelone and its derivatives exerted pronounced inhibitory response against all the species of bacterial organism tested, except E. coli. Bromohydroxy cedrelone and Michael adduct showed good antifungal activity.

  14. Antimicrobial Activity of Diterpenes from Viguiera arenaria against Endodontic Bacteria

    Directory of Open Access Journals (Sweden)

    Carlos H. G. Martins

    2011-01-01

    Full Text Available Six pimarane-type diterpenes isolated from Viguiera arenaria Baker and two semi-synthetic derivatives were evaluated in vitro against a panel of representative microorganisms responsible for dental root canal infections. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC against Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia, Prevotella buccae, Fusobacterium nucleatum, Bacteroides fragilis, Actinomyces naeslundii, Actinomyces viscosus, Peptostreptococcus micros, Enterococcus faecalis and Aggregatibacter actinomycetemcomitans. The compounds ent-pimara-8(14,15-dien-19-oic acid, its sodium salt and ent-8(14,15-pimaradien-3β-ol were the most active, displaying MIC values ranging from 1 to 10 μg mL-1. The results also allow us to conclude that minor structural differences among these diterpenes significantly influence their antimicrobial activity, bringing new perspectives to the discovery of new chemicals for use as a complement to instrumental endodontic procedures.

  15. Antimicrobial activity of extracts from Tamarindus indica L. leaves

    Directory of Open Access Journals (Sweden)

    Julio Cesar Escalona-Arranz

    2010-01-01

    Full Text Available Tamarindus indica L. leaves are reported worldwide as antibacterial and antifungal agents; however, this observation is not completely accurate in the case of Cuba. In this article, decoctions from fresh and sun dried leaves, as well as fluid extracts prepared with 30 and 70% ethanol-water and the pure essential oil from tamarind leaves were microbiologically tested against Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Pseudomona aeruginosa and Candida albicans. Aqueous and fluid extracts were previously characterized by spectrophotometric determination of their total phenols and flavonoids, while the essential oil was chemically evaluated by gas chromatography/mass spectroscopy (GC/MS. Experimental data suggest phenols as active compounds against B. subtilis cultures, but not against other microorganisms. On the other hand, the essential oil exhibited a good antimicrobial spectrum when pure, but its relative low concentrations in common folk preparations do not allow for any good activity in these extracts.

  16. Differential activity of innate defense antimicrobial peptides against Nocardia species

    Directory of Open Access Journals (Sweden)

    Wagner Dirk

    2010-02-01

    Full Text Available Abstract Background Members of the genus Nocardia are ubiquitous environmental saprophytes capable to cause human pulmonary, disseminated and cutaneous nocardiosis or bovine mastitis. Innate immunity appears to play an important role in early defense against Nocardia species. To elucidate the contribution of antimicrobial peptides (AMPs in innate defense against Nocardia, the activity of human α-defensins human neutrophil peptides (HNPs 1-3, human β-defensin (hBD-3 and cathelicidin LL-37 as well as bovine β-defensins lingual and tracheal antimicrobial peptides (LAP, TAP and bovine neutrophil-derived indolicidin against four important Nocardia species was investigated. Results Whereas N. farcinica ATCC 3318 and N. nova ATCC 33726 were found to be susceptible to all investigated human and bovine AMPs, N. asteroides ATCC 19247 was killed exclusively by neutrophil-derived human α-defensins HNP 1-3 and bovine indolicidin. N. brasiliensis ATCC 19296 was found to exhibit complete resistance to investigated human AMPs and to be susceptible only to bovine indolicidin. Conclusion Selected AMPs are capable to contribute to the first line of defense against Nocardia, yet, susceptibility appears to vary across different Nocardia species. Obtained results of neutrophil-derived AMPs to possess the broadest antinocardial spectrum are remarkable, since nocardiosis is characterized by a neutrophil-rich infiltrate in vivo.

  17. [Purification and antimicrobial activity of human neutrophil defensins].

    Science.gov (United States)

    Qu, X; Wang, A

    1991-11-01

    Neutrophils are one of the weapons of host defenses against microbial infection. Their ability to kill the invading microorganisms depends on two principle mechanisms. One depends on production of reactive oxygen intermediates (ROI) by stimulated neutrophils, and the other depends on the delivery of antimicrobial contents of the neutrophils' cytoplasmic granules, oxygen-independent. The defensins have the highest concentration in the neutrophils, and the broadest antimicrobial spectrum, being capable of killing gram-positive and gram-negative bacteria, fungi and some envelope viruses. We purified human defensins from the neutrophils' granules by gel permeation chromatography and SDS-preparative acrylamide gel electrophoresis. The molecular weight of human defensins is between 3,000-4,000 daltons. After testing, C. neoformans was susceptible to these defensins. Under condition of 37 degrees C, pH 7.4 and low ionic strength, antifungal activity by human defensins was related to its concentration and incubating time. All of these illustrate that nonoxidative killing mechanism of neutrophils, especially the function of defensins is very important in host defenses.

  18. Peptides from the scorpion Vaejovis punctatus with broad antimicrobial activity.

    Science.gov (United States)

    Ramírez-Carreto, Santos; Jiménez-Vargas, Juana María; Rivas-Santiago, Bruno; Corzo, Gerardo; Possani, Lourival D; Becerril, Baltazar; Ortiz, Ernesto

    2015-11-01

    The antimicrobial potential of two new non-disulfide bound peptides, named VpAmp1.0 (LPFFLLSLIPSAISAIKKI, amidated) and VpAmp2.0 (FWGFLGKLAMKAVPSLIGGNKSSSK) is here reported. These are 19- and 25-aminoacid-long peptides with +2 and +4 net charges, respectively. Their sequences correspond to the predicted mature regions from longer precursors, putatively encoded by cDNAs derived from the venom glands of the Mexican scorpion Vaejovis punctatus. Both peptides were chemically synthesized and assayed against a variety of microorganisms, including pathogenic strains from clinical isolates and strains resistant to conventional antibiotics. Two shorter variants, named VpAmp1.1 (FFLLSLIPSAISAIKKI, amidated) and VpAmp2.1 (FWGFLGKLAMKAVPSLIGGNKK), were also synthesized and tested. The antimicrobial assays revealed that the four synthetic peptides effectively inhibit the growth of both Gram-positive (Staphylococcus aureus and Streptococcus agalactiaea) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria, with MICs in the range of 2.5-24.0 μM; yeasts (Candida albicans and Candida glabrata) with MICs of 3.1-50.0 μM; and two clinically isolated strains of Mycobacterium tuberculosis-including a multi-drug resistant one- with MICs in the range of 4.8-30.5 μM. A comparison between the activities of the original peptides and their derivatives gives insight into the structural/functional role of their distinctive residues.

  19. Influence of montmorillonite on antimicrobial activity of tetracycline and ciprofloxacin

    Science.gov (United States)

    Lv, Guocheng; Pearce, Cody W.; Gleason, Andrea; Liao, Libing; MacWilliams, Maria P.; Li, Zhaohui

    2013-11-01

    Antibiotics are used not only to fight infections and inhibit bacterial growth, but also as growth promotants in farm livestock. Farm runoff and other farm-linked waste have led to increased antibiotic levels present in the environment, the impact of which is not completely understood. Soil, more specifically clays, that the antibiotic contacts may alter its effectiveness against bacteria. In this study a swelling clay mineral montmorillonite was preloaded with antibiotics tetracycline and ciprofloxacin at varying concentrations and bioassays were conducted to examine whether the antibiotics still inhibited bacterial growth in the presence of montmorillonite. Escherichia coli was incubated with montmorillonite or antibiotic-adsorbed montmorillonite, and then the number of viable bacteria per mL was determined. The antimicrobial activity of tetracycline was affected in the presence of montmorillonite, as the growth of non-resistant bacteria was still found even when extremely high TC doses were used. Conversely, in the presence of montmorillonite, ciprofloxacin did inhibit E. coli bacterial growth at high concentrations. These results suggest that the effectiveness of antimicrobial agents in clayey soils depends on the amount of antibiotic substance present, and on the interactions between the antibiotic and the clays in the soil, as well.

  20. Antioxidant, Antimicrobial Activity and Medicinal Properties of Grewia asiatica L.

    Science.gov (United States)

    Shukla, Ritu; Sharma, Dinesh C; Baig, Mohammad H; Bano, Shabana; Roy, Sudeep; Provazník, Ivo; Kamal, Mohammad A

    2016-01-01

    Since ancient time, India is a well known subcontinent for medicinal plants where diversity of plants is known for the treatment of many human disorders. Grewia asiatica is a dicot shrub belonging to the Grewioideae family and well known for its medicinally important fruit commonly called Falsa. G. asiatica, a seasonal summer plant is distributed in the forest of central India, south India, also available in northern plains and western Himalaya up to the height of 3000 ft. Fruits of G. asiatica are traditionally used as a cooling agent, refreshing drink, anti-inflammatory agent and for the treatment of some urological disorders. Recent advancement of Falsa researches concluded its antimicrobial and anti-diabetic activity. Since ancient time medicinal plants are traditionally used for the treatment of different diseases G. asiatica fruit is the edible and tasty part of the plant, now considered as a valuable source of unique natural product for the development of medicines which are used in different disease conditions like anti-diabetic, anti-inflammatory, anti-cancerous and antimicrobial. Now a days, G. asiatica is being used in different Ayurvedic formulation for the cure of different types of diseases. Different pharmacological investigations reveal the presence of phenols, saponnins, flavonoids and tannins compound in the fruits. Present review highlights the phytopharmacological and different traditional use of G. asiatica which is mentioned in ancient Ayurvedic texts. This review stimulates the researchers and scientists for further research on G. asiatica.

  1. Evaluation of antimicrobial activity of silver nanoparticles for carboxymethylcellulose film applications in food packaging.

    Science.gov (United States)

    Siqueira, Maria C; Coelho, Gustavo F; de Moura, Márcia R; Bresolin, Joana D; Hubinger, Silviane Z; Marconcini, José M; Mattoso, Luiz H C

    2014-07-01

    In this study, silver nanoparticles were prepared and incorporated into carboxymethylcellulose films to evaluate the antimicrobial activity for food packaging applications. The techniques carried out for material characterization were: infrared spectroscopy and thermal analysis for the silver nanoparticles and films, as well as particle size distribution for the nanoparticles and water vapor permeability for the films. The antimicrobial activity of silver nanoparticles prepared by casting method was investigated. The minimum inhibitory concentration (MIC) value of the silver nanoparticles to test Gram-positive (Enterococcus faecalis) and Gram-negative (Escherichia coli) microorganisms was carried out by the serial dilution technique, tested in triplicate to confirm the concentration used. The results were developed using the Mcfarland scale which indicates that the presence or absence of turbidity tube demonstrates the inhibition of bacteria in relation to the substance inoculated. It was found that the silver nanoparticles inhibited the growth of the tested microorganisms. The carboxymethylcellulose film embedded with silver nanoparticles showed the best antimicrobial effect against Gram-positive (E. faecalis) and Gram-negative (E. coli) bacteria (0.1 microg cm(-3)).

  2. The synthesis and antimicrobial activity of some 4-hydroxycoumarin derivatives.

    Science.gov (United States)

    Zavrsnik, Davorka; Muratović, Samija; Spirtović, Selma; Softić, Dzenita; Medić-Sarić, Marica

    2008-08-01

    Due to exceptional reactivity of 4-hydroxycoumarin, the synthesis of new coumarin derivatives of dimer and tetramer type has been carried out. The synthesis was carried out from 4-hydroxycoumarin and various aromatic aldehydes. In this way, compounds of the dimer 3,3'-(benzilidene)bis (4-hydroxycoumarin) type, as well as of the tetramer 3,3',3'',3'''-(1,4-dimethylenphenyl)tetra (4-hydroxycoumarin) type were prepared. The newly synthesized derivatives contain different functional groups, and as such they could exhibit microbiological activity. Therefore, we tested the microbiological activity of these derivatives on various species of bacteria and fungi. The tested compounds have shown different activity in terms of growth inhibition of microorganisms. Newly synthesized derivatives exhibit antibacterial activities, manifested as growth inhibition on Gram-positive bacteria types (Bacillus, Staphylococcus), while the activity against Candida was much weaker. The same compound did not show any antimicrobial activity against two Gram-negative bacteria types (Escherichia coli, Pseudomonas aeruginosa). The compound 1 showed the best microbiological activity. The obtained results confirmed its good antibacterial and antimycotic activities against different microorganisms.

  3. Antimicrobial activity of Ulva reticulata and its endophytes

    Science.gov (United States)

    Dhanya, K. I.; Swati, V. I.; Vanka, Kanth Swaroop; Osborne, W. J.

    2016-04-01

    Seaweeds are known to exhibit various antimicrobial properties, since it harbours an enormous range of indigenous bioactive compounds. The emergence of drug resistant strains has directed to the identification of prospective metabolites from seaweed and its endophytes, thereby exploiting the properties in resisting bacterial diseases. The current study was aimed to assess the antimicrobial activity of extracts obtained from Ulva reticulate, for which metabolites of Ulva reticulata and its endophytes were extracted and assessed against human pathogens like Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Bacillus subtilis. It was observed that the hexane extract of isolate VITDSJ2 was effective against all the tested pathogens but a significant inhibition was observed for Staphylococcus aureus and Escherichia coli. Further, Gas chromatography coupled with Mass spectroscopy (GC-MS) revealed the existence of phenol, 3, 5-bis (1, 1-dimethylethyl) in the crude hexane extract which is well-known to possess antibacterial activity. The effective isolate VITDSJ2 was identified to be the closest neighbour of Pseudomonas stutzeri by phenotypic and genotypic methods. The crude extracts of the seaweed Ulva reticulata was also screened for antibacterial activity and the hexane extract was effective in showing inhibition against all the tested pathogens. The compound in the crude extract of Ulva reticulata was identified as hentriacontane using GC-MS. The extracts obtained from dichloromethane did not show significant activity in comparison with the hexane extracts. Hence the metabolites of Ulva reticulata and the bacterial secondary metabolites of the endophytes could be used in the treatment of bacterial infections.

  4. In Vitro Antimicrobial and Modulatory Activity of the Natural Products Silymarin and Silibinin

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    Dayanne Rakelly de Oliveira

    2015-01-01

    Full Text Available Silymarin is a standardized extract from the dried seeds of the milk thistle (Silybum marianum L. Gaertn. clinically used as an antihepatotoxic agent. The aim of this study was to investigate the antibacterial and antifungal activity of silymarin and its major constituent (silibinin against different microbial strains and their modulatory effect on drugs utilized in clinical practice. Silymarin demonstrated antimicrobial activity of little significance against the bacterial strains tested, with MIC (minimum inhibitory concentration values of 512 µg/mL. Meanwhile, silibinin showed significant activity against Escherichia coli with a MIC of 64 µg/mL. The results for the antifungal activity of silymarin and silibinin demonstrated a MIC of 1024 µg/mL for all strains. Silymarin and silibinin appear to have promising potential, showing synergistic properties when combined with antibacterial drugs, which should prompt further studies along this line.

  5. Effect of different extraction procedures on antimicrobial activity of marine bivalves: A comparison

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, S.; Chatterji, A.; Das, P.

    was assessed on the antimicrobial activity. Antimicrobial assay was carried out against 8 bacterial strains (3 Gram positive and 5 negative bacteria) and 1 species of fungi. The AEH extracts showed higher activity against the tested organisms as compared to Me...

  6. In vitro antimicrobial activity of extracts and isolated constituents of Rubus ulmifolius.

    Science.gov (United States)

    Panizzi, L; Caponi, C; Catalano, S; Cioni, P L; Morelli, I

    2002-02-01

    The antimicrobial activity on bacteria and fungi of increasing polarity extracts of Rubus ulmifolius and that of some isolated constituents, quercetin-3-O-beta-D-glucuronide; kaempferol-3-O-beta-D-glucuronide, gallic acid, ferulic acid and tiliroside was evaluated. The phenolic and tannins fractions showed an high antimicrobial activity.

  7. Synthesis, antimicrobial and anticancer activities of amido sulfonamido methane linked bis heterocycles

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    Chokkappagari Premakumari

    2014-09-01

    Full Text Available A new class of amido sulfonamido methane linked bis heterocycles- bis-oxazoles, thiazoles and imidazoles were prepared and screened for antimicrobial and anticancer activities. The chloro substituted amido sulfonamido bisimidazole exhibited excellent antimicrobial activity and also it was the most potent compound on lung, colon and prostate cancer cell lines.

  8. Native thrombocidin-1 and unfolded thrombocidin-1 exert antimicrobial activity via distinct structural elements

    NARCIS (Netherlands)

    Kwakman, P.H.S.; Krijgsveld, J.; de Boer, L.; Nguyen, L.T.; Boszhard, L.; Vreede, J.; Dekker, H.L.; Speijer, D.; Drijfhout, J.W.; te Velde, A.A.; Crielaard, W.; Vogel, H.J.; Vandenbroucke-Grauls, C.M.J.E.; Zaat, S.A.J.

    2011-01-01

    Chemokines (chemotactic cytokines) can have direct antimicrobial activity, which is apparently related to the presence of a distinct positively charged patch on the surface. However, chemokines can retain antimicrobial activity upon linearization despite the loss of their positive patch, thus questi

  9. ANTIMICROBIAL ACTIVITY OF EXTRACTS OF IRIS HUNGARICA AND IRIS SIBIRICA

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    Kovalev V. M.

    2017-06-01

    Full Text Available Introduction. Referring to the latest data, infectious diseases command a large part of among the total number of pathologies in the world and are an important problem in medicine. The leading role in prevention and treatment of diseases of microbial origin belongs to antibacterial chemotherapeutic agents. Advantages of antibiotics of synthetic origin are the high activity compared to phytogenic drugs. But it is known that microorganisms can release the resistance to synthetic antibiotics, so the use of drugs based on the plant materials is appropriate: phytogenic drugs more rarely induce the formation of resistance of the strains of microorganisms, they have a gentle action, can be used for a long-term, have the low cost. Therefore, it is appropriate to examine the drug plants with the aim of determination their antibacterial activity.Iris hungarica Waldst et Kit. and Iris sibirica L. are the representatives of the family Iridaceae, genus Iris and they have a wide spectrum of the pharmacological activity. Biologically active substances that were recovered from plants of the genus Iris (tectoridin, iristectorigenin B, nigracin, kaempferol, quercetin, etc. exhibited an antitumor, antimicrobial, estrogenic, insecticidal, antiplasmatic, anticholinesterase action, they were the inhibitors of enzymes and exhibited the immunomodulatory properties, which made these plants perspective for the research study. Raw materials Irises are constituent components of more than 9 medicines. Materials and Methods. The objects of the study were the leaves and rhizomes of Iris hungarica and Iris sibirica that were prepared during the growing season in 2014 in the M.M. Gryshko National botanical garden (Kiev, Ukraine. The dry and lipophilic extracts from the leaves and rhizomes of Irises were used to establish the antimicrobial activity. For the study of extracts antimicrobial activity was used agar well diffusion method. According to the WHO recommendations the

  10. Antimicrobial and cytotoxic activity of Alnus glutinosa (L. Gaertn., A. incana (L. Moench, and A. viridis (Chaix DC. extracts

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    Sabina Dahija

    2016-07-01

    Full Text Available Introduction: The objective of the present study was to evaluate the antimicrobial and cytotoxic activities of water extracts of leaves and barks from Alnus glutinosa (L. Gaertn., A. incana (L. Moench, and A. viridis (Chaix DC.Methods: The antimicrobial activities of extracts were tested against gram-negative and gram-positive bacteria as well as yeast strains by the agar diffusion method. The cell viability was determined by the Trypan blue dye exclusion method.Results: The largest diameters of inhibition zone (DIZ were recorded with Staphylococcus aureus ATCC 6538 and Bacillus subtilis 168M. The highest percentage of cell viability was observed with water bark extracts of A. glutinosa (97.46%.Conclusions: Potential antimicrobial properties of A. glutinosa, A. incana, and A. viridis demonstrated in this study, as well as their low levels of toxicity, make them an interesting subject for further studies.

  11. Antioxidant, antimicrobial, cytotoxic and analgesic activities of ethanolic extract of Mentha arvensis L.

    Institute of Scientific and Technical Information of China (English)

    Nripendra Nath Biswas; Subarna Saha; Mohammed Khadem Ali

    2014-01-01

    Objective: To investigate potential antioxidant, antimicrobial, cytotoxic and analgesic activities of ethanolic extract of Mentha arvensis L. in different in vivo and in vitro experimental models. Methods: In vitro DPPH radical scavenging assay was used to evaluate the antioxidant activity of the plant extract. In vivo analgesic activity was carried out by acetic acid-induced writhing test in Swiss albino mice. All studies in mice were undertaken at the doses of 250 and 500 mg/kg body weight. Antibacterial activity was studied by disk diffusion assay against some Gram-positive and Gram-negative bacterial strains. Brine shrimp lethality assay was used to investigate cytotoxicity effects of the plant extract. Results:The extract showed free radical scavenging activity in the DPPH assay (IC50~41 µg/mL) compared to the standard antioxidant ascorbic acid (IC50~19 µg/mL). The extract also produced prominent antimicrobial activity against Salmonella typhi, Salmonella paratyphi, Shigella boydii,Streptococcus pyogenes and Streptococcus aureus compared to standard drug kanamycin at the dose of 30 µg/disc. The extract exhibited lethality against the brine shrimp nauplii with the LC50 values of 40 µg/mL, and also 90% mortality (LC90) value was found to be 160 µg/mL. In analgesic test, the extract demonstrated statistically significant (P Conclusions:These results suggest that the ethanolic extract of Mentha arvensis L. has potential antioxidant, antibacterial, cytotoxic and analgesic activities that support the ethnopharmacological uses of this plant.

  12. Antioxidant Activity, Polyphenols Content and Antimicrobial Activity of Several Native Pteridophytes of Romania

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    Liliana Cristina SOARE

    2012-05-01

    Full Text Available The aim of this paper was to test the antioxidant activity, polyphenols content and antimicrobial activity of crude extracts obtained from leaves of pteridophyte species commonly found in Romania. The ORAC (Oxygen Radical Absorbance Capacity of the investigated ferns varied between 421.90 ?mol TE (Trolox equivalents/g FW (fresh weight in Dryopteris filix-mas and 128.18 ?mol TE/g FW in D. affinis. Methanolic extracts obtained from leaves of ferns have similar antioxidant activity to that of some medicinal plants. Polyphenols content in the leaves of ferns varies between 2340 mg Gallic acid equivalents (GAE/100 g FW in D. filix-mas and 887 mg GAE/100 g FW in D. affinis. The correlation coefficient between ORAC and the total polyphenol content was R=0.985. This correlation suggests that phenolic compounds are major contributors to the antioxidant activity. The methanolic extract obtained from ferns inhibits the growth of Gram negative Escherichia coli ATCC 25922, Pseudomonas aeruginosa NBJMCC1390, Salmonella abony and Gram positive Staphyllococcus aureus ATCC 25093 and Enterococcus faecalis. The highest antimicrobial activity was determined for the Dryopteris extract. The antimicrobial activity of methanolic extracts obtained from leaves of D. filix-mas and D. affinis is better than the A. filix-femina in the case of Brevibacterium flavum ATCC 14067, Sarcina sp., Bacillus cereus ATCC 1390, Saccharomyces cerevisiae and Aspergillus niger. The tested ferns could be used as cosmetic ingredients, as preservatives in food or in antimicrobial therapy.

  13. Silver activation on thin films of Ag-ZrCN coatings for antimicrobial activity.

    Science.gov (United States)

    Ferreri, I; Calderon V, S; Escobar Galindo, R; Palacio, C; Henriques, M; Piedade, A P; Carvalho, S

    2015-10-01

    Nowadays, with the increase of elderly population and related health problems, knee and hip joint prosthesis are being widely used worldwide. However, failure of these invasive devices occurs in a high percentage thus demanding the revision of the chirurgical procedure. Within the reasons of failure, microbial infections, either hospital or subsequently-acquired, contribute in high number to the statistics. Staphylococcus epidermidis (S. epidermidis) has emerged as one of the major nosocomial pathogens associated with these infections. Silver has a historic performance in medicine due to its potent antimicrobial activity, with a broad-spectrum on the activity of different types of microorganisms. Consequently, the main goal of this work was to produce Ag-ZrCN coatings with antimicrobial activity, for the surface modification of hip prostheses. Thin films of ZrCN with several silver concentrations were deposited onto stainless steel 316 L, by DC reactive magnetron sputtering, using two targets, Zr and Zr with silver pellets (Zr+Ag target), in an atmosphere containing Ar, C2H2 and N2. The antimicrobial activity of the modified surfaces was tested against S. epidermidis and the influence of an activation step of silver was assessed by testing samples after immersion in a 5% (w/v) NaClO solution for 5 min. The activation procedure revealed to be essential for the antimicrobial activity, as observed by the presence of an inhibition halo on the surface with 11 at.% of Ag. The morphology analysis of the surface before and after the activation procedure revealed differences in silver distribution indicating segregation/diffusion of the metallic element to the film's surface. Thus, the results indicate that the silver activation step is responsible for an antimicrobial effect of the coatings, due to silver oxidation and silver ion release.

  14. Antimicrobial activity of selected phytochemicals against Escherichia coli and Staphylococcus aureus and their biofilms

    OpenAIRE

    2014-01-01

    Bacteria can be resistant to multiple antibiotics and we are fast approaching a time when antibiotics will not work on some bacterial infections. New antimicrobial compounds are urgently necessary. Plants are considered the greatest source to obtain new antimicrobials. This study aimed to assess the antimicrobial activity of four phytochemicals—7-hydroxycoumarin (7-HC), indole-3-carbinol (I3C), salicylic acid (SA) and saponin (SP)—against Escherichia coli and Staphylococcus aureus, either as...

  15. ANTIMICROBIAL ACTIVITY OF THE SUBSTANCES RECEIVED FROM RAW MATERIALS OF BIRCH FAMILY PLANTS

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    Fedchenkova Yu.A

    2016-12-01

    tenfold dilution of extracts on meat-peptone broth 1:10 and 1:100 to which there were added the referential cultures which are grown up on appropriate differential diagnostic medium depending on a type of cultures. The crops were incubated in the thermostat at t - 35-37 °C within 24-48 hours. For identification of test-strain growth of E. coli there was used Endo medium, for S. aureus – Chistovich medium, for B. subtilis and B. cereus - meat-peptone agar, for P. аeruginosa - 5% blood agar and for C. albicans – Saburo medium. As the solutions remained muddy after incubation, for the assessment of antimicrobial action of the received fractions, there were being made the cloning on differential and diagnostic mediums. Results and discussion. Data of the conducted researches of antimicrobial activity of various substances of hazel ordinary and black alder leaves – tinctures, lipophilic, spirit and polysacharide fractions are given in the table. The obtained data demonstrate that lipophilic fractions of hazel ordinary and black alder leaves possessed the bactericidal activity when it was diluted in the ratio of 1:10 and 1:100 concerning P. аeruginosa and E. coli. These fractions also have antimycotic activity concerning C. albicans. Concerning E. сoli it is revealed that the spirit fractions from black alder leaves had the bactericidal activity, and concerning P. аeruginosa and C. albicans – all studied spirit fractions possessed. Among polysacharide fractions the antimicrobial activity is revealed only for this substance of hazel ordinary leaves in both dilutions concerning E. coli, S. aureus, P. aeruginosa. As concerning B. subtilis and B. cereus, bacteria of these strains were resistant to all studied fractions. Conclusions. Antimicrobial activity of a number of substances of hazel ordinary and black alder leaves is studied. As a result of the conducted researches it is established that lipophilic and spirit fractions of hazel ordinary and black alder leaves

  16. Phytochemical investigation GC-MS analysis and in vitro antimicrobial activity of Coleus forskohlii

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    Krishnamoorthy Rajkumar

    2015-12-01

    Full Text Available The aim of this study was to investigate the phytochemical constituents, gas chromatography-mass spectrometry (GC-MS analysis and antimicrobial activity of Coleus forskohlii. The different solvents such as ethanol, chloroform, acetone and aqueous extracts were identified pharmacologically as important bioactive compounds and their antimicrobial properties were studied. In the phytochemical investigation almost all the ethanol extract of leaf, stem and root having secondary metabolites like alkaloids, flavonoids, tannins, saponins, terpenoids, and steroids. The active constituents of the ethanol extract of C. forskohlii root was studied by GC-MS analysis. According to the antimicrobial results ethanol extract of C. froshkolii root showed highest antibacterial activity compared with stem and leaf. The highest antimicrobial activity was observed against Klebsiella pneumonia (19 mm and Candida albicans (16 mm in ethanol extract of root. Among the above extracts of leaf, stem and root, ethanol extract of root having antimicrobial activities due to the presence of phytoconstituents.

  17. EVALUATION OF ANTIMICROBIAL AND ANTIOXIDANT ACTIVITY OF LEAF TEAS BLACKBERRY (MORUS NIGRA

    Directory of Open Access Journals (Sweden)

    P. Zanco

    2017-02-01

    Full Text Available Brazil has a long tradition in the use of plants, and is the same used in different ways, such as in the form of infusions and decoctions, for therapeutic purposes. Morus nigra species is a plant that has been used in different parts of the world as phytotherapy. This plant is known as mulberry, black, blackberry black or blackberry and various parts of the plant, such as leaves, fruit, bark and roots are used by the population, demonstrating anti-inflammatory activity, antioxidant, hypoglycemic, antimicrobial, among others. Because of the interest in research on the bioactivity of plant products and use of blackberry tea in the population, present study evaluated the antibacterial activity of teas M. nigra leaves obtained by infusion and decoction against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium, as well as the antioxidant potential of preparations by DPPH technique. Results revealed that the infusions and decoctions prepared with Morus nigra leaves showed no ability to inhibit the growth of bacteria tested. However, all preparations (decoctions and infusions obtained from the leaves showed antioxidant potential, demonstrated ability to reduce DPPH radical. Despite infusions and decoctions evaluated in this study do not show antimicrobial activity, both had significant antioxidant property. Considering the use of different plants, including mulberry tree, by the people, it is considered always important proof of their biological activities.

  18. Structure and antimicrobial activity of phloroglucinol derivatives from Achyrocline satureioides.

    Science.gov (United States)

    Casero, Carina; Machín, Félix; Méndez-Álvarez, Sebastián; Demo, Mirta; Ravelo, Ángel G; Pérez-Hernández, Nury; Joseph-Nathan, Pedro; Estévez-Braun, Ana

    2015-01-23

    The new prenylated phloroglucinol α-pyrones 1-3 and the new dibenzofuran 4, together with the known 23-methyl-6-O-demethylauricepyrone (5), achyrofuran (6), and 5,7-dihydroxy-3,8-dimethoxyflavone (gnaphaliin A), were isolated from the aerial parts of Achyrocline satureioides. Their structures were determined by 1D and 2D NMR spectroscopic studies, while the absolute configuration of the sole stereogenic center of 1 was established by vibrational circular dichroism measurements in comparison to density functional theory calculated data. The same (S) absolute configuration of the α-methylbutyryl chain attached to the phloroglucinol nucleus was assumed for compounds 2-6 based on biogenetic considerations. Derivatives 7-16 were prepared from 1 and 5, and the antimicrobial activities of the isolated metabolites and some of the semisynthetic derivatives against a selected panel of Gram-positive and Gram-negative bacteria, as well as a set of yeast molds, were determined.

  19. Underlying mechanism of antimicrobial activity of chitosan microparticles and implications for the treatment of infectious diseases.

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    Soo Jin Jeon

    Full Text Available The emergence of antibiotic resistant microorganisms is a great public health concern and has triggered an urgent need to develop alternative antibiotics. Chitosan microparticles (CM, derived from chitosan, have been shown to reduce E. coli O157:H7 shedding in a cattle model, indicating potential use as an alternative antimicrobial agent. However, the underlying mechanism of CM on reducing the shedding of this pathogen remains unclear. To understand the mode of action, we studied molecular mechanisms of antimicrobial activity of CM using in vitro and in vivo methods. We report that CM are an effective bactericidal agent with capability to disrupt cell membranes. Binding assays and genetic studies with an ompA mutant strain demonstrated that outer membrane protein OmpA of E. coli O157:H7 is critical for CM binding, and this binding activity is coupled with a bactericidal effect of CM. This activity was also demonstrated in an animal model using cows with uterine diseases. CM treatment effectively reduced shedding of intrauterine pathogenic E. coli (IUPEC in the uterus compared to antibiotic treatment. Since Shiga-toxins encoded in the genome of bacteriophage is often overexpressed during antibiotic treatment, antibiotic therapy is generally not recommended because of high risk of hemolytic uremic syndrome. However, CM treatment did not induce bacteriophage or Shiga-toxins in E. coli O157:H7; suggesting that CM can be a potential candidate to treat infections caused by this pathogen. This work establishes an underlying mechanism whereby CM exert antimicrobial activity in vitro and in vivo, providing significant insight for the treatment of diseases caused by a broad spectrum of pathogens including antibiotic resistant microorganisms.

  20. Chemical composition of three Parmelia lichens and antioxidant, antimicrobial and cytotoxic activities of some their major metabolites.

    Science.gov (United States)

    Manojlović, Nedeljko; Ranković, Branislav; Kosanić, Marijana; Vasiljević, Perica; Stanojković, Tatjana

    2012-10-15

    The aim of this study is to investigate chemical composition of acetone extracts of the lichens Parmelia caperata, P. saxatilis and P. sulcata and antioxidant, antimicrobial and anticancer activities of some their major metabolites. The phytochemical analysis of acetone extracts of three Parmelia lichens were determined by HPLC-UV method. The predominant phenolic compounds in these extracts were protocetraric and usnic acids (P. caperata) and depsidone salazinic acid (other two species). Besides these compounds, atranorin and chloroatranorin, were also detected in some of these extracts. Antioxidant activity of their isolated metabolites was evaluated by free radical scavenging, superoxide anion radical scavenging and reducing power. As a result of the study salazinic acid had stronger antioxidant activity than protocetraric acid. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration by the broth microdilution method. Both compounds were highly active with minimum inhibitory concentration values ranging from 0.015 to 1mg/ml. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using MTT method. Salazinic acid and protocetraric acid were found to be strong anticancer activity toward both cell lines with IC(50) values ranging from 35.67 to 60.18μg/ml. The present study shows that tested lichen compounds demonstrated a strong antioxidant, antimicrobial, and anticancer effects. That suggest that these lichens can be used as new sources of the natural antimicrobial agents, antioxidants and anticancer compounds.

  1. Artepillin C and phenolic compounds responsible for antimicrobial and antioxidant activity of green propolis and Baccharis dracunculifolia DC.

    Science.gov (United States)

    Veiga, R S; De Mendonça, S; Mendes, P B; Paulino, N; Mimica, M J; Lagareiro Netto, A A; Lira, I S; López, B G-C; Negrão, V; Marcucci, M C

    2017-04-01

    This study investigates the antimicrobial activity in Staphylococcus aureus isolates (methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA)) and antioxidant activity of green propolis, Baccharis dracunculifolia DC extracts and Artepillin C™. The amount of Artepillin C in different extracts was determined by high performance liquid chromatography analysis. Minimum inhibitory concentration 90 (MIC90) was determined using 40 isolates of S. aureus inoculated in Müeller-Hinton agar culture medium containing the green propolis and B. dracunculifolia DC extracts. PVEE (green propolis ethanolic extract) and BDEH (B. dracunculifolia hexanic extract) showed the greatest antimicrobial activity with MIC90 values of 246·3 and 295·5 μg ml(-1) respectively. Green propolis ethanolic and hexanic extracts (PVEE and PVEH respectively) showed the greatest antioxidant activity assessed by DPPH (1,1-diphenyl-2-picryl hydrazyl radical) with IC50 values of 13·09 and 95·86 μg ml(-1) respectively. Green propolis ethanolic displays better antimicrobial and antioxidant activities compared to other extracts. These activities may be related to the presence of Artepillin C in synergism with the other constituents of the extracts. In this study, the antimicrobial activity of the extracts of green propolis and B. dracunculifolia DC demonstrated in MRSA and MSSA clinical isolates indicated that they can be important tools to treat infections caused by these bacteria. © 2017 The Society for Applied Microbiology.

  2. Antimicrobial activities of commercial nanoparticles against an environmental soil microbe, Pseudomonas putida KT2440

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    Huang Wenjie

    2009-06-01

    Full Text Available Abstract Background The release of heavy metal-containing nanoparticles (NP into the environment may be harmful to the efficacy of beneficial microbes that function in element cycling, pollutant degradation and plant growth. Nanoparticles of Ag, CuO and ZnO are of interest as antimicrobials against pathogenic bacteria. We demonstrate here their antimicrobial activity against the beneficial soil microbe, Pseudomonas putida KT2440. Results Toxicity was detected in a KT2440 construct possessing a plasmid bearing the luxAB reporter genes. "As manufactured" preparations of nano- Ag, -CuO and -ZnO caused rapid dose-dependent loss of light output in the biosensor. Cell death accompanied loss in Lux activity with treatments by nano-Ag and -CuO, but with -ZnO the treatments were bacteriostatic rather than bactericidal. Bulk equivalents of these products showed no inhibitory activity, indicating that particle size was determinant in activity. Flow Field-Flow Fractionation (FlFFF of an aqueous suspension of the nano-CuO and ZnO revealed a small proportion of 5 nm NP and aggregated particulates with sizes ranging between 70 nm and 300 nm; the majority portion of material was aggregated into particles larger than 300 nm in size. Thus within the commercial preparation there may be microbially active and inactive forms. Conclusion The "as-made" NP of Ag, CuO and ZnO have toxic effects on a beneficial soil microbe, leading to bactericidal or bacteriostatic effects depending on the NP employed. The lack of toxicity from bulk materials suggests that aggregation of the NP into larger particles, possibly by factors present in the environment may reduce their nontarget antimicrobial activity.

  3. Antimicrobial and Cytotoxic Activity of Extracts of Ferula heuffelii Griseb. ex Heuff. and Its Metabolites.

    Science.gov (United States)

    Pavlović, Ivan; Petrović, Silvana; Milenković, Marina; Stanojković, Tatjana; Nikolić, Dejan; Krunić, Aleksej; Niketić, Marjan

    2015-10-01

    The antimicrobial and cytotoxic activities of isolates (CHCl3 and MeOH extracts and selected metabolites) obtained from the underground parts of the Balkan endemic plant Ferula heuffelii Griseb. ex Heuff. were assessed. The CHCl3 and MeOH extracts exhibited moderate antimicrobial activity, being more pronounced against Gram-positive than Gram-negative bacteria, especially against Staphylococcus aureus (MIC=12.5 μg/ml for both extracts) and Micrococcus luteus (MIC=50 and 12.5 μg/ml, resp.). Among the tested metabolites, (6E)-1-(2,4-dihydroxyphenyl)-3,7,11-trimethyl-3-vinyldodeca-6,10-dien-1-one (2) and (2S*,3R*)-2-[(3E)-4,8-dimethylnona-3,7-dien-1-yl]-2,3-dihydro-7-hydroxy-2,3-dimethylfuro[3,2-c]coumarin (4) demonstrated the best antimicrobial activity. Compounds 2 and 4 both strongly inhibited the growth of M. luteus (MIC=11.2 and 5.2 μM, resp.) and Staphylococcus epidermidis (MIC=22.5 and 10.5 μM, resp.) and compound 2 additionally also the growth of Bacillus subtilis (MIC=11.2 μM). The cytotoxic activity of the isolates was tested against three human cancer cell lines, viz., cervical adenocarcinoma (HeLa), chronic myelogenous leukemia (K562), and breast cancer (MCF-7) cells. The CHCl3 extract exhibited strong cytotoxic activity against all cell lines (IC50 <11.0 μg/ml). All compounds strongly inhibited the growth of the K562 and HeLa cell lines. Compound 4 exhibited also a strong activity against the MCF-7 cell line, comparable to that of cisplatin (IC50 =22.32±1.32 vs. 18.67±0.75μM).

  4. Nanofiber composites containing N-heterocyclic carbene complexes with antimicrobial activity

    Directory of Open Access Journals (Sweden)

    Elzatahry AA

    2012-06-01

    Full Text Available Ahmed A Elzatahry1,4, Abdullah M Al-Enizi1, Elsayed Ahmed Elsayed2,5, Rachel R Butorac3, Salem S Al-Deyab1, Mohammad AM Wadaan2, Alan H Cowley31Petrochemical Research Chair, Department of Chemistry, 2Chair of Advanced Proteomics & Cytomics Research, Faculty of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia; 3Department of Chemistry and Biochemistry, University of Texas at Austin, Austin, TX, USA; 4Institute of Advanced Technology and New Materials, City for Scientific Research and Technology Applications, New Borg Alrab, Alexandria, Egypt; 5Natural & Microbial Products Department, National Research Centre, Dokki, Cairo, EgyptAbstract: This report concerns nanofiber composites that incorporate N-heterocyclic carbenes and the use of such composites for testing antimicrobial and antifungal activities. The nanofiber composites were produced by electrospinning mixtures of the gold chloride or gold acetate complexes of a bis(iminoacenaphthene (BIAN-supported NHC with aqueous solutions of polyvinyl alcohol (PVA. The products were characterized by scanning-electron microscopy, which revealed that nanofibers in the range of 250–300 nm had been produced. The biological activities of the nanofiber composites were tested against two Gram-positive bacteria, six Gram-negative bacteria, and two fungal strains. No activity was evident against the fungal strains. However, the gold chloride complex was found to be active against all the Gram-positive pathogens and one of the Gram-negative pathogens. It was also found that the activity of the produced nanofibers was localized and that no release of the bioactive compound from the nanofibers was evident. The demonstrated antimicrobial activities of these novel nanofiber composites render them potentially useful as wound dressings.Keywords: nanofiber, electrospinning, N-Heterocyclic carbene, biopolymer, antimicrobial

  5. Foeniculum vulgare essential oils: chemical composition, antioxidant and antimicrobial activities.

    Science.gov (United States)

    Miguel, Maria Graça; Cruz, Cláudia; Faleiro, Leonor; Simões, Mariana T F; Figueiredo, Ana Cristina; Barroso, José G; Pedro, Luis G

    2010-02-01

    The essential oils from Foeniculum vulgare commercial aerial parts and fruits were isolated by hydrodistillation, with different distillation times (30 min, 1 h, 2 h and 3 h), and analyzed by GC and GC-MS. The antioxidant ability was estimated using four distinct methods. Antibacterial activity was determined by the agar diffusion method. Remarkable differences, and worrying from the quality and safety point of view, were detected in the essential oils. trans-Anethole (31-36%), alpha-pinene (14-20%) and limonene (11-13%) were the main components of the essentials oil isolated from F. vulgare dried aerial parts, whereas methyl chavicol (= estragole) (79-88%) was dominant in the fruit oils. With the DPPH method the plant oils showed better antioxidant activity than the fruits oils. With the TBARS method and at higher concentrations, fennel essential oils showed a pro-oxidant activity. None of the oils showed a hydroxyl radical scavenging capacity > 50%, but they showed an ability to inhibit 5-lipoxygenase. The essential oils showed a very low antimicrobial activity. In general, the essential oils isolated during 2 h were as effective, from the biological activity point of view, as those isolated during 3 h.

  6. Antimicrobial activity of a quaternary ammonium methacryloxy silicate-containing acrylic resin: a randomised clinical trial

    Science.gov (United States)

    Liu, Si-ying; Tonggu, Lige; Niu, Li-na; Gong, Shi-qiang; Fan, Bing; Wang, Liguo; Zhao, Ji-hong; Huang, Cui; Pashley, David H.; Tay, Franklin R.

    2016-01-01

    Quaternary ammonium methacryloxy silicate (QAMS)-containing acrylic resin demonstrated contact-killing antimicrobial ability in vitro after three months of water storage. The objective of the present double-blind randomised clinical trial was to determine the in vivo antimicrobial efficacy of QAMS-containing orthodontic acrylic by using custom-made removable retainers that were worn intraorally by 32 human subjects to create 48-hour multi-species plaque biofilms, using a split-mouth study design. Two control QAMS-free acrylic disks were inserted into the wells on one side of an orthodontic retainer, and two experimental QAMS-containing acrylic disks were inserted into the wells on the other side of the same retainer. After 48 hours, the disks were retrieved and examined for microbial vitality using confocal laser scanning microscopy. No harm to the oral mucosa or systemic health occurred. In the absence of carry-across effect and allocation bias (disks inserted in the left or right side of retainer), significant difference was identified between the percentage kill in the biovolume of QAMS-free control disks (3.73 ± 2.11%) and QAMS-containing experimental disks (33.94 ± 23.88%) retrieved from the subjects (P ≤ 0.001). The results validated that the QAMS-containing acrylic exhibits favourable antimicrobial activity against plaque biofilms in vivo. The QAMS-containing acrylic may also be used for fabricating removable acrylic dentures. PMID:26903314

  7. The antimicrobial activity of gramicidin A is associated with hydroxyl radical formation.

    Directory of Open Access Journals (Sweden)

    Je-Wen Liou

    Full Text Available Gramicidin A is an antimicrobial peptide that destroys gram-positive bacteria. The bactericidal mechanism of antimicrobial peptides has been linked to membrane permeation and metabolism disruption as well as interruption of DNA and protein functions. However, the exact bacterial killing mechanism of gramicidin A is not clearly understood. In the present study, we examined the antimicrobial activity of gramicidin A on Staphylococcus aureus using biochemical and biophysical methods, including hydroxyl radical and NAD+/NADH cycling assays, atomic force microscopy, and Fourier transform infrared spectroscopy. Gramicidin A induced membrane permeabilization and changed the composition of the membrane. The morphology of Staphylococcus aureus during gramicidin A destruction was divided into four stages: pore formation, water permeability, bacterial flattening, and lysis. Changes in membrane composition included the destruction of membrane lipids, proteins, and carbohydrates. Most interestingly, we demonstrated that gramicidin A not only caused membrane permeabilization but also induced the formation of hydroxyl radicals, which are a possible end product of the transient depletion of NADH from the tricarboxylic acid cycle. The latter may be the main cause of complete Staphylococcus aureus killing. This new finding may provide insight into the underlying bactericidal mechanism of gA.

  8. Mycosynthesis of silver and gold nanoparticles: Optimization, characterization and antimicrobial activity against human pathogens.

    Science.gov (United States)

    Balakumaran, M D; Ramachandran, R; Balashanmugam, P; Mukeshkumar, D J; Kalaichelvan, P T

    2016-01-01

    This study was aimed to isolate soil fungi from Kolli and Yercaud Hills, South India with the ultimate objective of producing antimicrobial nanoparticles. Among 65 fungi tested, the isolate, Bios PTK 6 extracellularly synthesized both silver and gold nanoparticles with good monodispersity. Under optimized reaction conditions, the strain Bios PTK 6 identified as Aspergillus terreus has produced extremely stable nanoparticles within 12h. These nanoparticles were characterized by UV-vis. spectrophotometer, HR-TEM, FTIR, XRD, EDX, SAED, ICP-AES and Zetasizer analyses. A. terreus synthesized 8-20 nm sized, spherical shaped silver nanoparticles whereas gold nanoparticles showed many interesting morphologies with a size of 10-50 nm. The presence and binding of proteins with nanoparticles was confirmed by FTIR study. Interestingly, the myco derived silver nanoparticles exhibited superior antimicrobial activity than the standard antibiotic, streptomycin except against Staphylococcus aureus and Bacillus subtilis. The leakage of intracellular components such as protein and nucleic acid demonstrated that silver nanoparticles damage the bacterial cells by formation of pores, which affects membrane permeability and finally leads to cell death. Further, presence of nanoparticles in the bacterial membrane and the breakage of cell wall were also observed using SEM. Thus, the obtained results clearly reveal that these antimicrobial nanoparticles could be explored as promising candidates for a variety of biomedical and pharmaceutical applications.

  9. Design of host defence peptides for antimicrobial and immunity enhancing activities.

    Science.gov (United States)

    McPhee, Joseph B; Scott, Monisha G; Hancock, Robert E W

    2005-05-01

    Host defense peptides are a vital component of the innate immune systems of humans, other mammals, amphibians, and arthropods. The related cationic antimicrobial peptides are also produced by many species of bacteria and function as part of the antimicrobial arsenal to help the producing organism reduce competition for resources from sensitive species. The antimicrobial activities of many of these peptides have been extensively characterized and the structural requirements for these activities are also becoming increasingly clear. In addition to their known antimicrobial role, many host defense peptides are also involved in a plethora of immune functions in the host. In this review, we examine the role of structure in determining antimicrobial activity of certain prototypical cationic peptides and ways that bacteria have evolved to usurp these activities. We also review recent literature on what structural components are related to these immunomodulatory effects. It must be stressed however that these studies, and the area of peptide research, are still in their infancy.

  10. Potentiating effect of ecofriendly synthesis of copper oxide nanoparticles using brown alga: antimicrobial and anticancer activities

    Indian Academy of Sciences (India)

    SRI VISHNU PRIYA RAMASWAMY; S NARENDHRAN; RAJESHWARI SIVARAJ

    2016-04-01

    This study reports the in vitro antimicrobial and anticancer activities of biologically synthesized copper nanoparticles. The antimicrobial activity of green synthesized copper oxide nanoparticles was assessed by well diffusion method. The anticancer activity of brown algae-mediated copper oxide nanoparticles was determined by MTT assay against the cell line (MCF-7). Maximum activity was observed with Pseudomonas aeruginosa and Aspergillus niger. Effective growth inhibition of cells was observed to be more than 93% in antibacterial activity. Thus, the results of the present study indicates that biologically synthesized copper nanoparticles can be used for several diseases, however, it necessitates clinical studies to ascertain their potential as antimicrobial and anticancer agents.

  11. Alternative Hand Contamination Technique To Compare the Activities of Antimicrobial and Nonantimicrobial Soaps under Different Test Conditions▿

    Science.gov (United States)

    Fuls, Janice L.; Rodgers, Nancy D.; Fischler, George E.; Howard, Jeanne M.; Patel, Monica; Weidner, Patrick L.; Duran, Melani H.

    2008-01-01

    Antimicrobial hand soaps provide a greater bacterial reduction than nonantimicrobial soaps. However, the link between greater bacterial reduction and a reduction of disease has not been definitively demonstrated. Confounding factors, such as compliance, soap volume, and wash time, may all influence the outcomes of studies. The aim of this work was to examine the effects of wash time and soap volume on the relative activities and the subsequent transfer of bacteria to inanimate objects for antimicrobial and nonantimicrobial soaps. Increasing the wash time from 15 to 30 seconds increased reduction of Shigella flexneri from 2.90 to 3.33 log10 counts (P = 0.086) for the antimicrobial soap, while nonantimicrobial soap achieved reductions of 1.72 and 1.67 log10 counts (P > 0.6). Increasing soap volume increased bacterial reductions for both the antimicrobial and the nonantimicrobial soaps. When the soap volume was normalized based on weight (∼3 g), nonantimicrobial soap reduced Serratia marcescens by 1.08 log10 counts, compared to the 3.83-log10 reduction caused by the antimicrobial soap (P soap resulted in a bacterial recovery of 2.49 log10 counts, compared to the 4.22-log10 (P soap. This indicates that nonantimicrobial soap was less active and that the effectiveness of antimicrobial soaps can be improved with longer wash time and greater soap volume. The transfer of bacteria to objects was significantly reduced due to greater reduction in bacteria following the use of antimicrobial soap. PMID:18441107

  12. Alternative hand contamination technique to compare the activities of antimicrobial and nonantimicrobial soaps under different test conditions.

    Science.gov (United States)

    Fuls, Janice L; Rodgers, Nancy D; Fischler, George E; Howard, Jeanne M; Patel, Monica; Weidner, Patrick L; Duran, Melani H

    2008-06-01

    Antimicrobial hand soaps provide a greater bacterial reduction than nonantimicrobial soaps. However, the link between greater bacterial reduction and a reduction of disease has not been definitively demonstrated. Confounding factors, such as compliance, soap volume, and wash time, may all influence the outcomes of studies. The aim of this work was to examine the effects of wash time and soap volume on the relative activities and the subsequent transfer of bacteria to inanimate objects for antimicrobial and nonantimicrobial soaps. Increasing the wash time from 15 to 30 seconds increased reduction of Shigella flexneri from 2.90 to 3.33 log(10) counts (P = 0.086) for the antimicrobial soap, while nonantimicrobial soap achieved reductions of 1.72 and 1.67 log(10) counts (P > 0.6). Increasing soap volume increased bacterial reductions for both the antimicrobial and the nonantimicrobial soaps. When the soap volume was normalized based on weight (approximately 3 g), nonantimicrobial soap reduced Serratia marcescens by 1.08 log(10) counts, compared to the 3.83-log(10) reduction caused by the antimicrobial soap (P soap resulted in a bacterial recovery of 2.49 log(10) counts, compared to the 4.22-log(10) (P bacterial recovery on balls handled by hands washed with nonantimicrobial soap. This indicates that nonantimicrobial soap was less active and that the effectiveness of antimicrobial soaps can be improved with longer wash time and greater soap volume. The transfer of bacteria to objects was significantly reduced due to greater reduction in bacteria following the use of antimicrobial soap.

  13. Antimicrobial activity of metal oxide nanoparticles supported onto natural clinoptilolite.

    Science.gov (United States)

    Hrenovic, Jasna; Milenkovic, Jelena; Daneu, Nina; Kepcija, Renata Matonickin; Rajic, Nevenka

    2012-08-01

    The antimicrobial activity of Cu(2)O, ZnO and NiO nanoparticles supported onto natural clinoptilolite was investigated in the secondary effluent under dark conditions. After 24h of contact the Cu(2)O and ZnO nanoparticles reduced the numbers of viable bacterial cells of Escherichia coli and Staphylococcus aureus in pure culture for four to six orders of magnitude and showed consistent 100% of antibacterial activity against native E. coli after 1h of contact during 48 exposures. The antibacterial activity of NiO nanoparticles was less efficient. The Cu(2)O and NiO nanoparticles showed 100% of antiprotozoan activity against Paramecium caudatum and Euplotes affinis after 1h of contact, while ZnO nanoparticles were less efficient. The morphology and crystallinity of the nanoparticles were not affected by microorganisms. The metal oxide nanoparticles could find a novel application in the disinfection of secondary effluent and removal of pathogenic microorganisms in the tertiary stage of wastewater treatment.

  14. Antioxidant and Antimicrobial Activities of Pogostemon cablin (Blanco Benth.

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    Bhanuz Dechayont

    2017-01-01

    Full Text Available Pogostemon cablin (Lamiaceae has been widely used in traditional medicine. In this study, the antioxidant and antimicrobial activities of leaves from P. cablin extracts were investigated. The water extracts had the highest total phenolic content 116.88±0.48 mg gallic acid equivalent/g of dry plant extract. Nevertheless, high levels of total flavonoid content were found in ethanolic extracts 280.12±2.04 mg quercetin equivalent/g of dry plant extract. The highest antioxidant activities were found for the ethanolic extract (IC50=18±0.90, 20±0.24 μg/mL by DPPH and ABTS scavenging assays, respectively. Both extracts showed moderate inhibition of superoxide inhibition (O2∙- and nitric oxide (NO production in concentration-dependent manner. Antibacterial activity was calculated by disk diffusion, minimum inhibitory concentration (MIC, and minimum bacterial concentration (MBC. The ethanolic extract had the greatest activity against methicillin resistant Staphylococcus aureus, methicillin sensitive S. aureus, and Streptococcus pyogenes with zone diameters of 11.67±1.53, 10.33±2.52, and 10.33±1.15 mm, respectively. The corresponding MIC and MBCs were 5, 0.625, and 0.039 mg/mL. P. cablin extracts contain antioxidant and antibacterial properties that should be exploited for possible clinical application.

  15. Molecular Identification of Streptomyces producing antibiotics and their antimicrobial activities

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    Latifa A. Al_husnan

    2016-12-01

    Full Text Available Five strains of Streptomyces, namely S, N, W, E and C (designations should be mentioned in detail here isolated from the rhizosphere soil cultivated with palm Alajua (date, pressed dates, AlMedina city, Saudi Arabia, were induced to produce antibiotics. Antimicrobial activities were determined on solid medium supplemented with starch. The detection was based on the formation of transparent zones around colonies. The results indicated that isolates had antibacterial activities against Staphylococcus aureus, Bacillus cereus, B. subtilis, Pseudomonas aeruginosa and also showed antifungal activity against Candida albicans and Aspergillus niger. DNA extracted from five isolates was used as template for 16s rDNA gene amplification. The expected PCR size was 1.5 kbp;1.6 kbp; 1.25 kbp; 1.25kbp and 1.0 k bp for S, N, W, E and C isolates respectively using universal 16s rDNA gene primers using direct PCR. The isolates varied morphologically on the basis of spore color, aerial and substrate mycelium formation, and production of diffusible pigment. Isolates were tested under a microscope by using slide culture technique. The results indicate that the soil of this region is source of Streptomyces having antibacterial and antifungal activity and thus better utilization of these microorganisms as biological control agents.

  16. Gram-positive bacterial cell envelopes: The impact on the activity of antimicrobial peptides.

    Science.gov (United States)

    Malanovic, Nermina; Lohner, Karl

    2016-05-01

    A number of cationic antimicrobial peptides, effectors of innate immunity, are supposed to act at the cytoplasmic membrane leading to permeabilization and eventually membrane disruption. Thereby, interaction of antimicrobial peptides with anionic membrane phospholipids is considered to be a key factor in killing of bacteria. Recently, evidence was provided that killing takes place only when bacterial cell membranes are completely saturated with peptides. This adds to an ongoing debate, which role cell wall components such as peptidoglycan, lipoteichoic acid and lipopolysaccharide may play in the killing event, i.e. if they rather entrap or facilitate antimicrobial peptides access to the cytoplasmic membrane. Therefore, in this review we focused on the impact of Gram-positive cell wall components for the mode of action and activity of antimicrobial peptides as well as in innate immunity. This led us to conclude that interaction of antimicrobial peptides with peptidoglycan may not contribute to a reduction of their antimicrobial activity, whereas interaction with anionic lipoteichoic acids may reduce the local concentration of antimicrobial peptides on the cytoplasmic membrane necessary for sufficient destabilization of the membranes and bacterial killing. Further affinity studies of antimicrobial peptides toward the different cell wall as well as membrane components will be needed to address this problem on a quantitative level. This article is part of a Special Issue entitled: Antimicrobial peptides edited by Karl Lohner and Kai Hilpert.

  17. Expression of mouse beta defensin 2 in Escherichia coli and its broad-spectrum antimicrobial activity

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    Tianxiang Gong

    2011-09-01

    Full Text Available Mature mouse beta defensin 2 (mBD2 is a small cationic peptide with antimicrobial activity. Here we established a prokaryotic expression vector containing the cDNA of mature mBD2 fused with thioredoxin (TrxA, pET32a-mBD2. The vector was transformed into Escherichia Coli (E. coli Rosseta-gami (2 for expression fusion protein. Under the optimization of fermentation parameters: induce with 0.6 mM isopropylthiogalactoside (IPTG at 34ºC in 2×YT medium and harvest at 6 h postinduction, fusion protein TrxA-mBD2 was high expressed in the soluble fraction (>95%. After cleaved fusion protein by enterokinase, soluble mature mBD2 was achieved 6 mg/L with a volumetric productivity. Purified recombinant mBD2 demonstrated clear broad-spectrum antimicrobial activity for fungi, bacteria and virus. The MIC of antibacterial activity of against Staphylococcus aureus was 50 µg/ml. The MIC of against Candida albicans (C. albicans and Cryptococcus neoformans (C. neoformans was 12.5µg/ml and 25µg/ml, respectively. Also, the antimicrobial activity of mBD2 was effected by NaCl concentration. Additionally, mBD2 showed antiviral activity against influenza A virus (IAV, the protective rate for Madin-Darby canine kidney cells (MDCK was 93.86% at the mBD2 concentration of 100 µg/ml. These works might provide a foundation for the following research on the mBD2 as therapeutic agent for medical microbes.

  18. Antimicrobial and antioxidative activity of various leaf extracts of Amphoricarpos vis. (Asteraceae taxa

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    Gavrilović Milan

    2016-01-01

    Full Text Available The antimicrobial and antioxidative activities of diethyl ether, 80% methanol and 50% acetone extracts of the leaves of three Amphoricarpos taxa (Asteraceae; A. neumayerianus, A. autariatus ssp. autariatus and A. autariatus ssp. bertisceus from the Balkan Peninsula were investigated. The antimicrobial activity was determined by the broth microdilution assay against eight bacterial and eight fungal species. The in vitro antioxidative activity was assessed by the DPPH assay. The total phenolic and flavonoid contents were also determined. The most sensitive bacterial species were Bacillus cereus and Staphylococcus aureus. The best antibacterial potential was obtained for the methanol extract of A. neumayerianus, while the diethyl ether extract of this species showed the lowest effect. In general, the tested extracts showed higher activity than the commercial antibiotics streptomycin and ampicillin. Also, all micromycetes were sensitive to the tested extracts. The most sensitive was Trichoderma viride. The highest and lowest antifungal effect was determined in A. a. ssp. autariatus for the diethyl ether and acetone extracts, respectively. The highest total phenolic and flavonoid contents were determined in the methanol extract of A. a. autariatus. The best antioxidative activity was demonstrated by the methanol extract of A. a. ssp. autariatus as comparing to matching extracts from the other two taxa.

  19. Antimicrobial activity of latex silver nanoparticles using Calotropis procera

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    Nadia Hussein Mohamed

    2014-11-01

    Conclusions: It can be concluded that serum latex of Calotropis procera was found to display strong potential for the synthesis of AgNPs as antimicrobial agents through rapid reduction of silver ions (Ag+ to Ag0. The green synthesized AgNPs were found to show higher antimicrobial efficacy than crude latex.

  20. Tolerance to the antimicrobial peptide colistin in Pseudomonas aeruginosa biofilms is linked to metabolically active cells, and depends on the pmr and mexAB-oprM genes.

    Science.gov (United States)

    Pamp, Sünje Johanna; Gjermansen, Morten; Johansen, Helle Krogh; Tolker-Nielsen, Tim

    2008-04-01

    Bacteria living as biofilm are frequently reported to exhibit inherent tolerance to antimicrobial compounds, and might therefore contribute to the persistence of infections. Antimicrobial peptides are attracting increasing interest as new potential antimicrobial therapeutics; however, little is known about potential mechanisms, which might contribute to resistance or tolerance development towards these compounds in biofilms. Here we provide evidence that a spatially distinct subpopulation of metabolically active cells in Pseudomonas aeruginosa biofilms is able to develop tolerance to the antimicrobial peptide colistin. On the contrary, biofilm cells exhibiting low metabolic activity were killed by colistin. We demonstrate that the subpopulation of metabolically active cells is able to adapt to colistin by inducing a specific adaptation mechanism mediated by the pmr operon, as well as an unspecific adaptation mechanism mediated by the mexAB-oprM genes. Mutants defective in either pmr-mediated lipopolysaccharide modification or in mexAB-oprM-mediated antimicrobial efflux were not able to develop a tolerant subpopulation in biofilms. In contrast to the observed pattern of colistin-mediated killing in biofilms, conventional antimicrobial compounds such as ciprofloxacin and tetracycline were found to specifically kill the subpopulation of metabolically active biofilm cells, whereas the subpopulation exhibiting low metabolic activity survived the treatment. Consequently, targeting the two physiologically distinct subpopulations by combined antimicrobial treatment with either ciprofloxacin and colistin or tetracycline and colistin almost completely eradicated all biofilm cells.

  1. Quantitative structure-activity relationships of antimicrobial fatty acids and derivatives against Staphylococcus aureus

    Institute of Scientific and Technical Information of China (English)

    Hui ZHANG; Lu ZHANG; Li-juan PENG; Xiao-wu DONG; Di WU; Vivian Chi-Hua WU; Feng-qin FENG

    2012-01-01

    Fatty acids and derivatives (FADs) are resources for natural antimicrobials.In order to screen for additional potent antimicrobial agents,the antimicrobial activities of FADs against Staphylococcus aureus were examined using a microplate assay.Monoglycerides of fatty acids were the most potent class of fatty acids,among which monotridecanoin possessed the most potent antimicrobial activity.The conventional quantitative structure-activity relationship (QSAR) and comparative molecular field analysis (CoMFA) were performed to establish two statistically reliable models (conventional QSAR:R2=0.942,Q2LOO=0.910; CoMFA:R2=0.979,Q2=0.588,respectively).Improved forecasting can be achieved by the combination of these two models that provide a good insight into the structureactivity relationships of the FADs and that may be useful to design new FADs as antimicrobial agents.

  2. Antimicrobial activity and phytochemical analysis of crude extracts and essential oils from medicinal plants.

    Science.gov (United States)

    Silva, N C C; Barbosa, L; Seito, L N; Fernandes, A

    2012-01-01

    We aimed to establish a phytochemical analysis of the crude extracts and performed GC-MS of the essential oils (EOs) of Eugenia uniflora L. (Myrtaceae) and Asteraceae species Baccharis dracunculifolia DC, Matricaria chamomilla L. and Vernonia polyanthes Less, as well as determining their antimicrobial activity. Establishment of the minimal inhibitory concentrations of the crude extracts and EOs against 16 Staphylococcus aureus and 16 Escherichia coli strains from human specimens was carried out using the dilution method in Mueller-Hinton agar. Some phenolic compounds with antimicrobial properties were established, and all EOs had a higher antimicrobial activity than the extracts. Matricaria chamomilla extract and E. uniflora EO were efficient against S. aureus strains, while E. uniflora and V. polyanthes extracts and V. polyanthes EO showed the best antimicrobial activity against E. coli strains. Staphylococcus aureus strains were more susceptible to the tested plant products than E. coli, but all natural products promoted antimicrobial growth inhibition.

  3. Chemical Composition and Antimicrobial Activity of Thymus praecox Opiz ssp. polytrichus Essential Oil from Serbia

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    Nada V. Petrović

    2016-03-01

    Full Text Available Chemical composition and antimicrobial activity of the essential oil of wild growing Thymus praecox Opiz ssp. polytrichus were studied. trans-Nerolidol (19.79%, germacrene D (18.48% and thymol (9.62% were the main components in essential oil. This study is the first report of the antimicrobial activity of essential oil obtained from the T. praecox Opiz ssp. polytrichus. Antimicrobial activity of essential oil was investigated on Bacillus cereus, Micrococcus flavus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, Enterobacter cloacae, Salmonella typhimurium, Aspergillus fumigatus, A. versicolor, A. ochraceus, A. niger, Trichoderma viride, Penicillium funiculosum, P. ochrochloron, and P. verrucosum var. cyclopium strains. In the antimicrobial assays, essential oil showed high antimicrobial potential (MIC 19–150 m g/mL, MBC 39–300 m g/mL for bacteria; and MIC 19.5–39 m g/mL, MFC 39–78 m g/mL for fungi.

  4. Chemical composition and antimicrobial activities of leaves of sweet basil (Ocimum basilicum L. herb

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    Hadush Gebrehiwot

    2015-10-01

    Conclusion: So, the study has showed that the observed antimicrobial effect of O. basilicum essential oil on the bacterial and fungal isolate, though in vitro appear interesting and promising. So, emphasize have to made on the antimicrobial activities of the plant during the time of drug extraction. [Int J Basic Clin Pharmacol 2015; 4(5.000: 869-875

  5. The in-vitro antimicrobial activity of some medicinal plants against beta-lactam-resistant bacteria

    OpenAIRE

    Gangoue Pieboji, Joseph; Eze, N.; Ngongang Djintchui, A.; Ngameni, B; Tsabang, N.; Pegnyemb, D. E.; Biyiti, L.; Ngassam, P.; Koulla-Shiro, S.; Galleni, Moreno

    2009-01-01

    BACKGROUND: In effort to identify novel bacterial agents, this study was initiated to evaluate the antimicrobial properties of 17 crude extracts from 12 medicinal plants against beta-lactam-resistant bacteria. METHODOLOGY: The antimicrobial activities of plant extracts were evaluated against clinically proved beta-lactam-resistant bacteria (Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter cloacae, Serratia marcescens, Acinetobacter baumannii, Staphylococcus aureus and Enterococcus sp.)...

  6. Antimicrobial and antioxidant activities of three Mentha species essential oils.

    Science.gov (United States)

    Mimica-Dukić, Neda; Bozin, Biljana; Soković, Marina; Mihajlović, Biserka; Matavulj, Milan

    2003-05-01

    The present study describes the antimicrobial activity and free radical scavenging capacity (RSC) of essential oils from Mentha aquatica L., Mentha longifolia L., and Mentha piperita L. The chemical profile of each essential oil was determined by GC-MS and TLC. All essential oils exhibited very strong antibacterial activity, in particularly against Esherichia coli strains. The most powerful was M. piperita essential oil, especially towards multiresistant strain of Shigella sonei and Micrococcus flavus ATTC 10,240. All tested oils showed significant fungistatic and fungicidal activity [expressed as minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) values, respectively], that were considerably higher than those of the commercial fungicide bifonazole. The essential oils of M. piperita and M. longifolia were found to be more active than the essential oil of M. aquatica. Especially low MIC (4 microL/mL) and MFC (4 microL/mL) were found with M. piperita oil against Trichophyton tonsurans and Candida albicans (both 8 microL/mL). The RSC was evaluated by measuring the scavenging activity of the essential oils on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and OH radicals. All examined essential oils were able to reduce DPPH radicals into the neutral DPPH-H form, and this activity was dose-dependent. However, only the M. piperita oil reduced DPPH to 50 % (IC50 = 2.53 microg/mL). The M. piperita essential oil also exhibited the highest OH radical scavenging activity, reducing OH radical generation in the Fenton reaction by 24 % (pure oil). According to GC-MS and TLC (dot-blot techniques), the most powerful scavenging compounds were monoterpene ketones (menthone and isomenthone) in the essential oils of M. longifolia and M. piperita and 1,8-cineole in the oil of M. aquatica.

  7. Antimicrobial and Antioxidant Activities of Plants from Northeast of Mexico

    Directory of Open Access Journals (Sweden)

    Ricardo Salazar-Aranda

    2011-01-01

    Full Text Available Traditional medicine has a key role in health care worldwide. Obtaining scientific information about the efficacy and safety of the plants from our region is one of the goals of our research group. In this report, 17 plants were selected and collected in different localities from northeast Mexico. The dried plants were separated into leaves, flowers, fruit, stems, roots and bark. Each part was extracted with methanol, and 39 crude extracts were prepared. The extracts were tested for their antimicrobial activity using three Gram-negative bacterial strains (Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii, three Gram-positive bacterial strains (Enterococcus faecalis and two Staphylococcus aureus strains, and seven clinically isolated yeasts (Candida albicans, C. krusei, C. tropicalis, C. parapsilosis and C. glabrata; their antioxidant activity was tested using a DPPH free radical assay. No activity against Gram-negative bacteria was observed with any extract up to the maximum concentration tested, 1000 μg ml−1. We report here for the first time activity of Ceanothus coeruleus against S. aureus (flowers, minimal inhibitory concentration (MIC 125 μg ml−1, C. glabrata (MICs 31.25 μg ml−1 and C. parapsilosis (MICs between 31.25 and 125 μg ml−1; Chrysanctinia mexicana against C. glabrata (MICs 31.25 μg ml−1; Colubrina greggii against E. faecalis (MICs 250 μg ml−1 and Cordia boissieri against C. glabrata (MIC 125 μg ml−1. Furthermore, this is the first report about antioxidant activity of extracts from Ceanothus coeruleus, Chrysanctinia mexicana, Colubrina greggii and Cyperus alternifolius. Some correlation could exist between antioxidant activity and antiyeast activity against yeasts in the species Ceanothus coeruleus, Schinus molle, Colubrina greggii and Cordia boissieri.

  8. Antimicrobial and antioxidant activities of plants from northeast of Mexico.

    Science.gov (United States)

    Salazar-Aranda, Ricardo; Pérez-López, Luis Alejandro; López-Arroyo, Joel; Alanís-Garza, Blanca Alicia; Waksman de Torres, Noemí

    2011-01-01

    Traditional medicine has a key role in health care worldwide. Obtaining scientific information about the efficacy and safety of the plants from our region is one of the goals of our research group. In this report, 17 plants were selected and collected in different localities from northeast Mexico. The dried plants were separated into leaves, flowers, fruit, stems, roots and bark. Each part was extracted with methanol, and 39 crude extracts were prepared. The extracts were tested for their antimicrobial activity using three Gram-negative bacterial strains (Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii), three Gram-positive bacterial strains (Enterococcus faecalis and two Staphylococcus aureus strains), and seven clinically isolated yeasts (Candida albicans, C. krusei, C. tropicalis, C. parapsilosis and C. glabrata); their antioxidant activity was tested using a DPPH free radical assay. No activity against Gram-negative bacteria was observed with any extract up to the maximum concentration tested, 1000 μg ml(-1). We report here for the first time activity of Ceanothus coeruleus against S. aureus (flowers, minimal inhibitory concentration (MIC) 125 μg ml(-1)), C. glabrata (MICs 31.25 μg ml(-1)) and C. parapsilosis (MICs between 31.25 and 125 μg ml(-1)); Chrysanctinia mexicana against C. glabrata (MICs 31.25 μg ml(-1)); Colubrina greggii against E. faecalis (MICs 250 μg ml(-1)) and Cordia boissieri against C. glabrata (MIC 125 μg ml(-1)). Furthermore, this is the first report about antioxidant activity of extracts from Ceanothus coeruleus, Chrysanctinia mexicana, Colubrina greggii and Cyperus alternifolius. Some correlation could exist between antioxidant activity and antiyeast activity against yeasts in the species Ceanothus coeruleus, Schinus molle, Colubrina greggii and Cordia boissieri.

  9. In vitro antimicrobial activity of the aminoglycoside arbekacin tested against oxacillin-resistant Staphylococcus aureus isolated in Brazilian hospitals

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    Julio C. R. Cordeiro

    Full Text Available Arbekacin is an aminoglycoside used in Japan for treating infections caused by gentamicin and oxacillin-resistant S. aureus (ORSA. The objective of this study was to determine the in vitro antimicrobial activity of arbekacin against 454 clinical isolates of ORSA. The isolates were consecutively collected between January and July, 2000, from patients hospitalized in 8 Brazilian medical centers. The antimicrobial susceptibility testing was performed by disk diffusion method according to NCCLS recommendations. The vast majority of the isolates, 453 strains (99.8%, were considered susceptible to arbekacin based on the criteria proposed by the Requirements for Antibiotic Products of Japan. Only 1 isolate (0.2% was classified as resistant. On the other hand, high rates of resistance were demonstrated for other aminoglycosides, such as gentamicin (97.6% resistance and amikacin (97.0% resistance. Resistance rate was also high for ciprofloxacin (98.0%. All isolates were considered susceptible to vancomycin. The excellent in vitro antimicrobial activity of arbekacin demonstrated in this study indicates that this antimicrobial agent may play an important role in the treatment of severe ORSA infections, especially those that show poor clinical response with vancomycin monotherapy. Since the aminoglycosides should not be used as monotherapy to treat Gram positive infections, further studies evaluating in vitro and in vivo synergistic activity of arbekacin combinations are necessary to clarify the clinical role of this aminoglycoside.

  10. In vitro antimicrobial activity of the aminoglycoside arbekacin tested against oxacillin-resistant Staphylococcus aureus isolated in Brazilian hospitals

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    Cordeiro Julio C. R.

    2001-01-01

    Full Text Available Arbekacin is an aminoglycoside used in Japan for treating infections caused by gentamicin and oxacillin-resistant S. aureus (ORSA. The objective of this study was to determine the in vitro antimicrobial activity of arbekacin against 454 clinical isolates of ORSA. The isolates were consecutively collected between January and July, 2000, from patients hospitalized in 8 Brazilian medical centers. The antimicrobial susceptibility testing was performed by disk diffusion method according to NCCLS recommendations. The vast majority of the isolates, 453 strains (99.8%, were considered susceptible to arbekacin based on the criteria proposed by the Requirements for Antibiotic Products of Japan. Only 1 isolate (0.2% was classified as resistant. On the other hand, high rates of resistance were demonstrated for other aminoglycosides, such as gentamicin (97.6% resistance and amikacin (97.0% resistance. Resistance rate was also high for ciprofloxacin (98.0%. All isolates were considered susceptible to vancomycin. The excellent in vitro antimicrobial activity of arbekacin demonstrated in this study indicates that this antimicrobial agent may play an important role in the treatment of severe ORSA infections, especially those that show poor clinical response with vancomycin monotherapy. Since the aminoglycosides should not be used as monotherapy to treat Gram positive infections, further studies evaluating in vitro and in vivo synergistic activity of arbekacin combinations are necessary to clarify the clinical role of this aminoglycoside.

  11. Antimicrobial activities of isothiocyanates against Campylobacter jejuni isolates

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    Virginie eDufour

    2012-04-01

    Full Text Available Food-borne human infection with Campylobacter jejuni is a medical concern in both industrialized and developing countries. Efficient eradication of C. jejuni reservoirs within live animals and processed foods is limited by the development of antimicrobial resistances and by practical problems related to the use of conventional antibiotics in food processes.We have investigated the bacteriostatic and bactericidal activities of two phytochemicals, allyl-isothiocyanate (AITC and benzyl-isothiocyanate (BITC, against 24 C. jejuni isolates from chicken feces, human infections and contaminated foods, as well as two reference strains NCTC11168 and 81-176.Both AITC and BITC displayed a potent antibacterial activity against C. jejuni. BITC showed a higher overall antibacterial effect (MIC of 2.5 to 5 g mL-1 compared to AITC (MIC of 50 to 200 g mL-1. Interestingly, the 24 C. jejuni isolates could be classified in 3 groups according to their sensitivity levels to both compounds, suggesting that AITC and BITC shared identical activity mechanisms and consequently faced similar resistance processes in bacterial cells.The sensitivity levels of C. jejuni strains against isothiocyanates were neither correlated with the presence of a GGT (-Glutamyl Transpeptidase encoding gene in the genome nor with the origin of the biological sample. However the ggt mutant of C. jejuni 81-176 displayed a decreased survival rate compared to WT when exposed to ITC.

  12. Antimicrobial Activity of Five Medicinal Plants on Candida Albicans

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    Fatemeh Masomi

    2016-10-01

    Full Text Available Background: In recent years, drug resistance to human pathogenic fungi has been increased. Medicinal plants are one way to overcome antibiotic resistance. The aim of this study was to evaluate the antifungal and inhibitory activity of five medicinal plants on the growth of Candida albicans. Methods: This study was done in the Microbiology Lab of Shahid Bahonar University of Kerman, Iran in 2015. Five medicinal plants include: Trachyspermum ammi (seed, Teucrium polium (leaf, Piper nigrum (seed, Pistachia vera (skin, Camelia sinensis (leaf were collected. Collected plant materials were extracted by ethanol and methanol solvent with maceration method. Antifungal activity of the ethanolic and methanolic extracts was evaluated by paper disc diffusion and agar well diffusion methods. Besides, MIC and MBC of each extract was determined. Results: All plant extracts had sufficient inhibitory effect against C. albicans but the extracts of P. vera had the best inhibitory effect on C. albicans (ZOI: 40 mm. The lowest antifungal effect between these five plants related to Piper nigrum (ZOI: 13 mm. Besides, the P. vera extracts had the best MIC and MBC values (6.25 and 12.5 mg/ml. Conclusion: This study strongly evidence the maximum antimicrobial activity of medicinal plants against C. albicans that this inhibitory effect varies with the different solvent-extract form. A more comprehensive study need to identify the effective compounds that have these antifungal properties.

  13. Multifunctional antimicrobial proteins and peptides: natural activators of immune systems.

    Science.gov (United States)

    Niyonsaba, François; Nagaoka, Isao; Ogawa, Hideoki; Okumura, Ko

    2009-01-01

    In addition to the physical barrier of the stratum corneum, cutaneous innate immunity also includes the release of various humoral mediators, such as cytokines and chemokines, recruitment and activation of phagocytes, and the production of antimicrobial proteins/peptides (AMPs). AMPs form an innate epithelial chemical shield, which provides a front-line component in innate immunity to inhibit microbial invasion; however, this might be an oversimplification of the diverse functions of these molecules. In fact, apart from exhibiting a broad spectrum of microbicidal properties, it is increasingly evident that AMPs display additional activities that are related to the stimulation and modulation of the cutaneous immune system. These diverse functions include chemoattraction and activation of immune and/or inflammatory cells, the production and release of cytokines and chemokines, acceleration of angiogenesis, promotion of wound healing, neutralization of harmful microbial products, and bridging of both innate and adaptive immunity. Thus, better understanding of the functions of AMPs in skin and identification of their signaling mechanisms may offer new strategies for the development of potential therapeutics for the treatment of infection- and/or inflammation-related skin diseases. Here, we briefly outline the structure, regulation of expression, and multifunctional roles of principal skin-derived AMPs.

  14. Antimicrobial activity of biopolymer–antibiotic thin films fabricated by advanced pulsed laser methods

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Popescu, C.; Dorcioman, G.; Miroiu, F.M.; Socol, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Gittard, S.D.; Miller, P.R.; Narayan, R.J. [Biomedical Engineering, University of North Carolina and North Carolina State University, Chapel Hill, NC 27599-7575 (United States); Enculescu, M. [National Institute for Materials Physics, PO Box MG-7, Bucharest-Magurele (Romania); Chrisey, D.B. [Tulane University, Department of Physics and Engineering Physics, New Orleans, LA (United States)

    2013-08-01

    We report on thin film deposition by matrix assisted pulsed laser evaporation (MAPLE) of two polymer–drug composite thin film systems. A pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) was used to deposit composite thin films of poly(D,L-lactide) (PDLLA) containing several gentamicin concentrations. FTIR spectroscopy was used to demonstrate that MAPLE-transferred materials exhibited chemical structures similar to those of drop cast materials. Scanning electron microscopy data indicated that MAPLE may be used to fabricate thin films of good morphological quality. The activity of PDLLA–gentamicin composite thin films against Staphylococcus aureus bacteria was demonstrated using drop testing. The influence of drug concentration on microbial viability was also assessed. Our studies indicate that polymer–drug composite thin films prepared by MAPLE may be used to impart antimicrobial activity to implants, medical devices, and other contact surfaces.

  15. Antimicrobial Activity of Selected Phytochemicals against Escherichia coli and Staphylococcus aureus and Their Biofilms

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    Joana Monte

    2014-06-01

    Full Text Available Bacteria can be resistant to multiple antibiotics and we are fast approaching a time when antibiotics will not work on some bacterial infections. New antimicrobial compounds are urgently necessary. Plants are considered the greatest source to obtain new antimicrobials. This study aimed to assess the antimicrobial activity of four phytochemicals—7-hydroxycoumarin (7-HC, indole-3-carbinol (I3C, salicylic acid (SA and saponin (SP—against Escherichia coli and Staphylococcus aureus, either as planktonic cells or as biofilms. These bacteria are commonly found in hospital-acquired infections. Some aspects on the phytochemicals mode of action, including surface charge, hydrophobicity, motility and quorum-sensing inhibition (QSI were investigated. In addition, the phytochemicals were combined with three antibiotics in order to assess any synergistic effect. 7-HC and I3C were the most effective phytochemicals against E. coli and S. aureus. Both phytochemicals affected the motility and quorum-sensing (QS activity, which means that they can play an important role in the interference of cell-cell interactions and in biofilm formation and control. However, total biofilm removal was not achieved with any of the selected phytochemicals. Dual combinations between tetracycline (TET, erythromycin (ERY and ciprofloxacin (CIP and I3C produced synergistic effects against S. aureus resistant strains. The overall results demonstrates the potential of phytochemicals to control the growth of E. coli and S. aureus in both planktonic and biofilm states. In addition, the phytochemicals demonstrated the potential to act synergistically with antibiotics, contributing to the recycling of old antibiotics that were once considered ineffective due to resistance problems.

  16. Synthesis and Antimicrobial Activity of Furochromone, Benzofuran and Furocoumarin Derivatives Bearing Sulfonyl Moiety

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    Sadia A. Hessein

    2016-06-01

    Full Text Available New visnagin-9-sulfonamide derivatives 3 and 4a−c were synthesized through the reaction of visnagin-9-sulfonyl chloride 2 with amino compounds. Acetylation of compounds 4b and 4c gave the monoacetyl and diacetyl derivatives 5 and 6, respectively. Diazotization reaction of compound 4b afforded the corresponding benzotriazole derivative 8. Pyrazole and thiopyrimidine derivatives 9 and 10 were obtained via the opening of pyrone ring upon reaction of compound 3 with hydrazine hydrate and thiourea, respectively. In addition, hydrolysis of compound 3 with potassium hydroxide furnished the visnaginone derivative 11 which used as starting material for synthesize benzofuran derivatives 12−14 and bergaptene derivatives 15−17. The synthesized compounds were tested for antimicrobial activity. Furochromone derivatives 3, 4a−c, 5, 6 and 8 (visnagin-9-sulfonamide derivatives demonstrate moderate antibacterial and antifungal activities compared with the antibacterial and antifungal activites of the standard drugs. Benzofuran derivatives 11−14 (visnaginone derivatives showed the lowest antimicrobial activity among all the compounds investigated in this study. Furocoumarin derivatives 15a,b, 16 and 17 (furobenzopyransulfonamide [bergaptensulfonamides] are moderately active against all the tested strains. This work is licensed under a Creative Commons Attribution 4.0 International License.

  17. Synthesis, surface-active properties, and antimicrobial activities of new double-chain gemini surfactants.

    Science.gov (United States)

    Murguía, Marcelo C; Vaillard, Victoria A; Sánchez, Victoria G; Conza, José Di; Grau, Ricardo J

    2008-01-01

    A novel series of neutral and cationic dimeric surfactants were prepared involving ketalization reaction, Williamson etherification, and regioselective oxirane ring opening with primary and tertiary alkyl amines. The critical micelle concentration (CMC), effectiveness of surface tension reduction (gamma(CMC)), surface excess concentration (Gamma), and area per molecule at the interface (A) were determined and values indicate that the cationic series is characterized by good surface-active and self-aggregation properties. For the first time, we reported the antimicrobial activities against representative bacteria and fungi for dimeric compounds. The antimicrobial activity was found to be dependent on the target microorganism (Gram-positive bacteria > fungi > Gram-negative bacteria), as well as both the neutral or ionic nature (cationic > neutral) and alkyl chain length (di-C(12) > di-C(18) > di-C(8)) of the compounds. The cationic di-C(12) derivative was found to have equipotent activity to that of benzalkonium chloride (BAC) used as standard.

  18. Testing methods for antimicrobial activity of TiO2 photocatalyst

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    Markov Siniša L.

    2014-01-01

    Full Text Available In recent years, a lot of commercial TiO2 photocatalyst products have been developed and extensively studied for prospective and safe antimicrobial application in daily life, medicine, laboratories, food and pharmaceutical industry, waste water treatments and in development of new self-cleaning and antimicrobial materials, surfaces and paints. This paper reviews the studies published worldwide on killing microorganisms, methods for testing the antimicrobial activity, light sources and intensities, as well as calculation methods usually used when evaluating the antimicrobial properties of the TiO2-based products. Additionally, some strengths and weaknesses of the available methods for testing the antimicrobial activity of TiO2 photocatalyst products have been pointed out.[Projekat Ministarstva nauke Republike Srbije, br. III45008

  19. Discovery of novel histidine-derived lipo-amino acids: applied in the synthesis of ultra-short antimicrobial peptidomimetics having potent antimicrobial activity, salt resistance and protease stability.

    Science.gov (United States)

    Ahn, Mija; Murugan, Ravichandran N; Jacob, Binu; Hyun, Jae-Kyung; Cheong, Chaejoon; Hwang, Eunha; Park, Hyo-Nam; Seo, Ji-Hyung; Srinivasrao, G; Lee, Kyung S; Shin, Song Yub; Bang, Jeong Kyu

    2013-10-01

    Here we report for the first time the synthesis of Histidine (His) derived lipo-amino acids having pendant lipid tails at N(τ)- and N(π)-positions on imidazole group of His and applied it into synthesis of lipo-peptides. The attachment of His-derived lipo-amino acid into the very short inactive cationic peptides endows potent antimicrobial activity against Gram-positive and Gram-negative bacteria without hemolytic activity. Furthermore, our designed His-derived lipo-peptidomimetics (HDLPs) consisting of two or three residues displayed strong anti-MRSA activity and protease stability as well as retained potent antimicrobial activity under high salt concentration. Our results demonstrate that the novel lipo-amino acid is highly flexible to synthesize and carry out the extensive structure-activity relationship (SAR) on lipo-antimicrobial peptidomimetics and represents a unique amenable platform for modifying parameters important for antimicrobial activity. Through this study, we proved that the discovery of His-derived lipo-amino acid and the corresponding HDLPs are an excellent candidate as a lead compound for the development of novel antimicrobial agents. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. Antimicrobial activities of isothiocyanates against Campylobacter jejuni isolates.

    Science.gov (United States)

    Dufour, Virginie; Alazzam, Bachar; Ermel, Gwennola; Thepaut, Marion; Rossero, Albert; Tresse, Odile; Baysse, Christine

    2012-01-01

    Food-borne human infection with Campylobacter jejuni is a medical concern in both industrialized and developing countries. Efficient eradication of C. jejuni reservoirs within live animals and processed foods is limited by the development of antimicrobial resistances and by practical problems related to the use of conventional antibiotics in food processes. We have investigated the bacteriostatic and bactericidal activities of two phytochemicals, allyl-isothiocyanate (AITC), and benzyl isothiocyanate (BITC), against 24 C. jejuni isolates from chicken feces, human infections, and contaminated foods, as well as two reference strains NCTC11168 and 81-176. AITC and BITC displayed a potent antibacterial activity against C. jejuni. BITC showed a higher overall antibacterial effect (MIC of 1.25-5 μg mL(-1)) compared to AITC (MIC of 50-200 μg mL(-1)). Both compounds are bactericidal rather than bacteriostatic. The sensitivity levels of C. jejuni isolates against isothiocyanates were neither correlated with the presence of a GGT (γ-Glutamyl Transpeptidase) encoding gene in the genome, with antibiotic resistance nor with the origin of the biological sample. However the ggt mutant of C. jejuni 81-176 displayed a decreased survival rate compared to wild-type when exposed to ITC. This work determined the MIC of two ITC against a panel of C. jejuni isolates, showed that both compounds are bactericidal rather than bacteriostatic, and highlighted the role of GGT enzyme in the survival rate of C. jejuni exposed to ITC.

  1. Antimicrobial activity of Bauhinia tomentosa and Bauhinia vahlii roots

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    Swarnalatha Dugasani

    2010-01-01

    Full Text Available The hexane, ethylacetate and methanol extracts from Bauhinia tomentosa and Bauhinia vahlii roots were tested for their antimicrobial activity against Gram-positive bacteria (four strains, Gram-negative bacteria (three strains and three fungi strains using microdilution methods, for the determination of minimal inhibition concentration (MIC and the minimal microbicidal concentration (MMC. The MIC values of hexane extracts of B. tomentosa and B. vahlii roots were more than 250 μg/ml. The MIC values of ethylacetate and methanol extracts of B. tomentosa roots varied from 7.81 to 31.25 μg/ml and 31.25 to 62.50 μg/ml, respectively. The MIC values of ethylacetate and methanol extracts of B. vahlii roots varied from 15.63 to 62.5 μg/ml and 62.5 to 250 μg/ml, respectively. MMC values obtained are two times greater than the corresponding MIC values. The activities of ethylacetate extracts are attributed to the presence of flavonoids and that of methanol extracts are attributed to the presence of tannins.

  2. Salacia crassifolia (Celastraceae: CHEMICAL CONSTITUENTS AND ANTIMICROBIAL ACTIVITY

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    Vanessa G. Rodrigues

    2015-02-01

    Full Text Available The phytochemical study of hexane extract from leaves of Salacia crassifolia resulted in the isolation of 3β-palmitoxy-urs-12-ene, 3-oxofriedelane, 3β-hydroxyfriedelane, 3-oxo-28-hydroxyfriedelane, 3-oxo-29-hydroxyfriedelane, 28,29-dihydroxyfriedelan-3-one, 3,4-seco-friedelan-3-oic acid, 3β-hydroxy-olean-9(11:12-diene and the mixture of α-amirin and β-amirin. β-sitosterol, the polymer gutta-percha, squalene and eicosanoic acid were also isolated. The chemical structures of these constituents were established by IR, 1H and 13C NMR spectral data. Crude extracts and the triterpenes were tested against Entamoeba histolytica, Giardia lamblia and Trichomonas vaginalis and no activity was observed under the in vitro assay conditions. The hexane, chloroform, ethyl acetate and ethanol crude extracts, and the constituent 3,4-seco-friedelan-3-oic acid and 28,29-dihydroxyfriedelan-3-one showed in vitro antimicrobial activity against Salmonella typhimurium, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Streptococcus sanguinis and Candida albicans.

  3. The Study of the Antimicrobial Activity of Transylvanian (Romanian Propolis

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    Liviu Alexandru MARGHITAS

    2010-12-01

    Full Text Available The aim of the present study was to investigate the antibacterial activity of propolis samples collected from various regions in Transylvania (Romania against six bacterial strains: three Gram-positive bacteria (Staphylococcus aureus ATCC 6538P, Bacillus cereus ATCC 14579, Listeria monocytogenes ATCC 7644, two Gram-negative bacteria (Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 27853 and one yeast strain (Candida albicans ATCC 90028. Ethanolic extracts of the studied samples were prepared for the evaluation of antimicrobial activity, which was appreciated by measuring the inhibition zones diameters. The methodology used was agar diffusion technique inside Petri dishes with nine wells. Enroxil was used as control. A better sensibility of the Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes was noticed; the diameter of the inhibition zones ranged between 8 mm and 17 mm. As for Gram-negative bacteria, results were different for every tested bacterial strain. Inhibition zones diameter for E. coli ranged between 7 mm and 12 mm, while for P. aeruginosa a total resistance was noticed. Inhibition zones diameters for Candida albicans showed a variation which ranged between 0 mm and 10 mm. Minimum inhibitory concentration (MIC was evaluated for sample PS 20 due to the positive results showed against Staphylococcus aureus. According to the results obtained, it might be concluded that the tested propolis samples showed good results against Gram-positive bacteria.

  4. Antimicrobial activity of medicinal plants against oral microorganisms.

    Science.gov (United States)

    More, G; Tshikalange, T E; Lall, N; Botha, F; Meyer, J J M

    2008-10-28

    Ethanol extracts of eight plant species used traditionally in South Africa for the treatment of oral diseases were investigated for in vitro antimicrobial activity against oral pathogens namely Actinobacillus actinomycetemcomitans, Actinomyces naeslundii, Actinomyces israelii, Candida albicans, Porphyromonus gingivalis, Privotella intermedia and Streptococcus mutans using the disk diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ethanol extracts were determined against these microorganisms using micro dilution. The cytotoxicity and therapeutic index (TI) of selected active extracts were also determined. Out of eight plants, six (Annona senegalensis, Englerophytum magalismontanum, Dicerocarym senecioides, Euclea divinorum, Euclea natalensis, Solanum panduriforme and Parinari curatellifolia) exhibited MIC values ranging from 25.0 mg/ml to 0.8 mg/ml. Gram negative bacteria were found to be more resistant to the plant extracts than Gram positive bacteria, except for Euclea natalensis which inhibited all three Gram negative bacteria tested in this study. All plant extracts showed moderate cytotoxicity on the Vero cell line. The fifty percent inhibitory concentration (IC(50)) of all plants tested range from 92.3 to 285.1 microg/ml.

  5. Characterization of antimicrobial peptide activity by electrochemical impedance spectroscopy

    Science.gov (United States)

    Chang, William K.; Wimley, William C.; Searson, Peter C.; Hristova, Kalina; Merzlyakov, Mikhail

    2008-01-01

    Summary Electrochemical impedance spectroscopy performed on surface-supported bilayer membranes allows for the monitoring of changes in membrane properties, such as thickness, ion permeability, and homogeneity, after exposure to antimicrobial peptides (AMPs). We show that two model cationic peptides, very similar in sequence but different in activity, induce dramatically different changes in membrane properties as probed by impedance spectroscopy. Moreover, the impedance results excluded the “barrel-stave” and the “toroidal pore” models of AMP mode of action, and are more consistent with the “carpet” and the “detergent” models. The impedance data provide important new insights about the kinetics and the scale of the peptide action which currently are not addressed by the “carpet” and the “detergent” models. The method presented not only provides additional information about the mode of action of a particular AMP, but offers a means of characterizing AMP activity in reproducible, well-defined quantitative terms. PMID:18657512

  6. Structure-activity relationship of benzophenanthridine alkaloids from Zanthoxylum rhoifolium having antimicrobial activity.

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    Luciana de C Tavares

    Full Text Available Zanthoxylum rhoifolium (Rutaceae is a plant alkaloid that grows in South America and has been used in Brazilian traditional medicine for the treatment of different health problems. The present study was designed to evaluate the antimicrobial activity of the steam bark crude methanol extract, fractions, and pure alkaloids of Z. rhoifolium. Its stem bark extracts exhibited a broad spectrum of antimicrobial activity, ranging from 12.5 to 100 µg/mL using bioautography method, and from 125 to 500 µg/mL in the microdilution bioassay. From the dichloromethane basic fraction, three furoquinoline alkaloids (1-3, and nine benzophenanthridine alkaloids (4-12 were isolated and the antimicrobial activity of the benzophenanthridine alkaloids is discussed in terms of structure-activity relationships. The alkaloid with the widest spectrum of activity was chelerythrine (10, followed by avicine (12 and dihydrochelerythrine (4. The minimal inhibitory concentrations of chelerythrine, of 1.50 µg/mL for all bacteria tested, and between 3.12 and 6.25 µg/mL for the yeast tested, show this compound to be a more powerful antimicrobial agent when compared with the other active alkaloids isolated from Z. rhoifolium. To verify the potential importance of the methylenedioxy group (ring A of these alkaloids, chelerythrine was selected to represent the remainder of the benzophenanthridine alkaloids isolated in this work and was subjected to a demethylation reaction giving derivative 14. Compared to chelerythrine, the derivative (14 was less active against the tested bacteria and fungi. Kinetic measurements of the bacteriolytic activities of chelerythrine against the bacteria Bacillus subtilis (Gram-positive and Escherichia coli (Gram-negative were determined by optical density based on real time assay, suggesting that its mechanism of action is not bacteriolytic. The present study did not detect hemolytic effects of chelerythrine on erythrocytes and found a protective

  7. Surface-engineered core-shell nano-size ferrites and their antimicrobial activity

    Energy Technology Data Exchange (ETDEWEB)

    Baraliya, Jagdish D., E-mail: jdbaraliya@yahoo.co.in; Joshi, Hiren H., E-mail: jdbaraliya@yahoo.co.in [Department of Physics, Saurashtra University, Rajkot - 360 005, Gujarat (India)

    2014-04-24

    We report the results of biological study on core-shell structured MFe{sub 2}O{sub 4} (where M = Co, Mn, Ni) nanoparticles and influence of silica- DEG dual coating on their antimicrobial activity. Spherical MFe{sub 2}O{sub 4} nanoparticles were prepared via a Co-precipitation method. The microstructures and morphologies of these nanoparticles were studied by x-ray diffraction and FTIR. The antimicrobial activity study carried out in nutrient agar medium with addition of antimicrobial synthesis compound which is tested for its activity against different types of bacteria.

  8. Synthesis, anti-microbial activity and molecular docking studies on triazolylcoumarin derivatives

    Indian Academy of Sciences (India)

    Chinnadurai Satheeshkumar; Mahalingam Ravivarma; Pandian Arjun; Vaithiyanathan Silambarasan; Nanjian Raaman; Devadasan Velmurugan; Changsik Song; Perumal Rajakumar

    2015-03-01

    A series of triazolylcoumarins was synthesized by the cycloaddition of acetylenic derivatives to azide in the presence of Cu(I) catalyst at room temperature. All the synthesized compounds were evaluated for their anti-microbial activity against Gram-positive (B. subtilis and S. aureus), Gram-negative bacteria (K. pneumonia and P. vulgaris) and human pathogenic fungi (C. tropicalis and C. krusei), with tetracycline and fluconazole as standards for anti-microbial and anti-fungal activity. Triazolylcoumarins exhibit anti-microbial activity against all the tested pathogens, which is further supported by molecular docking studies.

  9. ANTIMICROBIAL ACTIVITY OF ROSA CANINA FLOWERS AGAINST SELECTED MICROORGANISMS

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    Katarína Rovná

    2015-02-01

    Full Text Available Rosa canina flowers were screened against various plant pathogenic microbial strains to study the antimicrobial properties of the plant. Ethanolic and methanolic extracts of flowers were screened applying agar well diffusion method against two Gram-negative bacteria including Escherichia coli CCM 3988 and Pseudomonas aeruginosa CCM 1960 and three microscopic filamentous fungi strains Aspergillus niger, Fusarium culmorum and Alternaria alternata, respectively. The best antimicrobial effect of ethanolic extract of Rosa canina flowers was found against Pseudomonas aeruginosa and the best antimicrobial effect of methanolic extract of Rosa canina flowers was found against Escherichia coli.

  10. Composition and antimicrobial activity of the essential oils from the Phebalium squamulosum species complex (Rutaceae) in New South Wales, Australia.

    Science.gov (United States)

    Sadgrove, Nicholas J; Telford, Ian R H; Greatrex, Ben W; Jones, Graham L

    2014-01-01

    Essential oils have been hydrodistilled and characterized from 21 populations of taxa currently assigned to the endemic Australian species Phebalium squamulosum (Rutaceae: Boronieae) using GC-MS, NMR and quantified using GC-FID. Essential oils were further examined using principle component analysis to distinguish chemotypes, then screened for antimicrobial activity using broth dilution and TLC-bioautography. Collections of subspecies of P. squamulosum, namely subsp. coriaceum, subsp. gracile, subsp. lineare, subsp. squamulosum, subsp. ozothamnoides and subsp. verrucosum, were made from the wild and one from a cultivated plant of known provenance within New South Wales. Results demonstrated considerable intra- and interspecific essential oil component variation, suggesting the existence of distinct chemotypes and supporting previously observed segregate species based on morphological evidence. Antimicrobial testing revealed moderate to high activity for all essential oils dominated by sesquiterpene alcohols; elemol and eudesmol isomers. Conversely, very low antimicrobial activity was observed from essential oils dominated by monoterpenes. This study constitutes the most exhaustive investigation of essential oils from P. squamulosum subspecies to date and provides the first report of antimicrobial activity.

  11. STUDIES ON ANTIMICROBIAL ACTIVITY AND PHYTOCHEMICAL ANALYSIS OF CITRUS FRUIT JUICES AGAINST SELECTED ENTERIC PATHOGENS

    OpenAIRE

    Bansode.D.S.; Chavan.M.D.

    2012-01-01

    The present study was carried out to find out the antimicrobial activity and phytochemical study of citrus fruit juices viz. Lemon (Citrus limon) and Orange (Citrus ourantium) against medically important selected enteric pathogens. As microorganisms are becoming resistant to present day antibiotics, our study focuses on antimicrobial activity and phytochemical study of Citrus fruit juices against selected enteric pathogens. Biological active compounds present in the medicinal important fruit ...

  12. ANALYSIS OF BIOACTIVE COMPOUNDS AND ANTIMICROBIAL ACTIVITY OF MARINE ALGAE KAPPAPHYCUS ALVAREZII USING THREE SOLVENT EXTRACTS

    Directory of Open Access Journals (Sweden)

    V. Prabha*, D.J. Prakash and P.N. Sudha

    2013-01-01

    Full Text Available The seaweeds are economically valuable resources, used as food, fodder, fertilizer and medicine and thus useful to mankind in many ways. In the present study, Kappaphycus alvarezii, a marine alga, has been analysed for the presence of bioactive products using three solvent extracts. Antimicrobial activity was also done using the same extracts of seaweed. The results revealed that the selected seaweed has active secondary metabolites and also exhibited antimicrobial activity, mainly in the methanolic extract of Kappaphycus alvarezii.

  13. Antimicrobial Activity of Rhoeo discolor Phenolic Rich Extracts Determined by Flow Cytometry

    OpenAIRE

    Rebeca García-Varela; Rebeca M. García-García; Bertha A. Barba-Dávila; Oscar R. Fajardo-Ramírez; Serna-Saldívar, Sergio O.; Cardineau, Guy A

    2015-01-01

    Traditional medicine has led to the discovery of important active substances used in several health-related areas. Phytochemicals in Rhoeo discolor extracts have proven to have important antimicrobial activity. In the present study, our group determined the antimicrobial effects of extracts of Rhoeo discolor, a plant commonly used in Mexico for both medicinal and ornamental purposes. We evaluated the in vitro activity of phenolic rich extracts against specifically chosen microorganisms of hum...

  14. Synergistic antimicrobial activity of Camellia sinensis and Juglans regia against multidrug-resistant bacteria.

    Science.gov (United States)

    Farooqui, Amber; Khan, Adnan; Borghetto, Ilaria; Kazmi, Shahana U; Rubino, Salvatore; Paglietti, Bianca

    2015-01-01

    Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR) bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs) were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA) strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens.

  15. Synergistic antimicrobial activity of Camellia sinensis and Juglans regia against multidrug-resistant bacteria.

    Directory of Open Access Journals (Sweden)

    Amber Farooqui

    Full Text Available Synergistic combinations of antimicrobial agents with different mechanisms of action have been introduced as more successful strategies to combat infections involving multidrug resistant (MDR bacteria. In this study, we investigated synergistic antimicrobial activity of Camellia sinensis and Juglans regia which are commonly used plants with different antimicrobial agents. Antimicrobial susceptibility of 350 Gram-positive and Gram-negative strains belonging to 10 different bacterial species, was tested against Camellia sinensis and Juglans regia extracts. Minimum inhibitory concentrations (MICs were determined by agar dilution and microbroth dilution assays. Plant extracts were tested for synergistic antimicrobial activity with different antimicrobial agents by checkerboard titration, Etest/agar incorporation assays, and time kill kinetics. Extract treated and untreated bacteria were subjected to transmission electron microscopy to see the effect on bacterial cell morphology. Camellia sinensis extract showed higher antibacterial activity against MDR S. Typhi, alone and in combination with nalidixic acid, than to susceptible isolates." We further explore anti-staphylococcal activity of Juglans regia that lead to the changes in bacterial cell morphology indicating the cell wall of Gram-positive bacteria as possible target of action. The synergistic combination of Juglans regia and oxacillin reverted oxacillin resistance of methicillin resistant Staphylococcus aureus (MRSA strains in vitro. This study provides novel information about antimicrobial and synergistic activity of Camellia sinensis and Juglans regia against MDR pathogens.

  16. Experimental active control results from the SPICES smart structure demonstrations

    Science.gov (United States)

    Flamm, David S.; Toth, G. K.; Chou, Kenneth C.; Heck, Larry P.; Nowlin, William C.; Titterton, Paul J., Sr.

    1996-05-01

    The final demonstrations of the ARPA SPICES (Synthesis and Processing of Intelligent Cost Effective Structures) program test the control of two active vibration mounts manufactured from composites with embedded actuators and sensors. Both mount demonstrations address wide band control problems for real disturbances, one at low frequency and the other at high frequency. The control systems for both are two-level hierarchies, with an inner active damping augmentation loop and an outer vibration control loop. We first review the control design requirements for the demonstration and summarize our control design approach. Then we focus on presenting the experimental results of the final demonstrations. For the low frequency demonstration, two alternative control approaches were demonstrated, one involving finite impulse response modeling and the other state space modeling. For the high frequency demonstration only the finite impulse response modeling approach was used because of computational limitations due to the complex system dynamics.

  17. Plant species used in dental diseases: ethnopharmacology aspects and antimicrobial activity evaluation.

    Science.gov (United States)

    Vieira, Denise R P; Amaral, Flavia MaM; Maciel, Márcia C G; Nascimento, Flávia R F; Libério, Silvana A; Rodrigues, Vandílson P

    2014-09-29

    Ethnopharmacological surveys show that several plant species are used empirically by the population, in oral diseases. However, it is necessary to check the properties of these plant species. To evaluate in vitro antimicrobial activity against Streptococcus mutans from plant species selected in a previous ethnopharmacology study. An ethnopharmacological survey was conducted with users of a dental clinic school services, located in Sao Luis, Maranhão, Brazil, aiming to identify plant species used in oral diseases treatment. From the ethnopharmacological survey, species were selected for in vitro antimicrobial activity evaluation against Streptococcus mutans, by agar diffusion method and determination of Minimum Inhibitory Concentration (MIC). Two hundred and seventy one people participated in the research: 55.7% reported the use of plants for medicinal purposes, 29.5% of which have knowledge and/or use plants for some type of oral disease. Thirty four species belonging to 24 (twenty four) botanical families were reported, being Aloe vera L., Anacardium occidentale L., Schinus terebinthifolius Raddi, Chenopodium ambrosioides L. and Punica granatum L. the most cited. The most commonly reported indications were healing after tooth extraction, followed by toothache, inflammation and bleeding gums., The determination of Minimum Inhibitory Concentration (MIC) demonstrated that Punica granatum L., Psidium guajava L. and Schinus terebinthifolius Raddi showed similar activity to 0.12% chlorhexidine, used as positive control. That result is important to follow up the study of these species in the search for new anticariogenic agents originated by plants. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Liquid-crystalline ordering of antimicrobial peptide-DNA complexes controls TLR9 activation

    Science.gov (United States)

    Schmidt, Nathan W.; Jin, Fan; Lande, Roberto; Curk, Tine; Xian, Wujing; Lee, Calvin; Frasca, Loredana; Frenkel, Daan; Dobnikar, Jure; Gilliet, Michel; Wong, Gerard C. L.

    2015-07-01

    Double-stranded DNA (dsDNA) can trigger the production of type I interferon (IFN) in plasmacytoid dendritic cells (pDCs) by binding to endosomal Toll-like receptor-9 (TLR9; refs , , , , ). It is also known that the formation of DNA-antimicrobial peptide complexes can lead to autoimmune diseases via amplification of pDC activation. Here, by combining X-ray scattering, computer simulations, microscopy and measurements of pDC IFN production, we demonstrate that a broad range of antimicrobial peptides and other cationic molecules cause similar effects, and elucidate the criteria for amplification. TLR9 activation depends on both the inter-DNA spacing and the multiplicity of parallel DNA ligands in the self-assembled liquid-crystalline complex. Complexes with a grill-like arrangement of DNA at the optimum spacing can interlock with multiple TLR9 like a zipper, leading to multivalent electrostatic interactions that drastically amplify binding and thereby the immune response. Our results suggest that TLR9 activation and thus TLR9-mediated immune responses can be modulated deterministically.

  19. Mutagenic, antimutagenic, antioxidant, anti-lipoxygenase and antimicrobial activities of Scandix pecten-veneris L.

    Science.gov (United States)

    Sharifi-Rad, M; Tayeboon, G S; Miri, A; Sharifi-Rad, M; Setzer, W N; Fallah, F; Kuhestani, K; Tahanzadeh, N; Sharifi-Rad, J

    2016-05-30

    Scandix pecten-veneris L. or Shepherd's-needle is a weed species used in some countries for medicinal purposes. In this study S. pecten-veneris leaves were shade dried, powdered and extracted with methanol. The purpose of this study was to assay the in vitro mutagenic, antimutagenic, antioxidant, antilipoxygenase and antimicrobial activities of S. pecten-veneris leaf extract. The methanolic extract indicated no mutagenicity when tested with Salmonella typhimurium strains TA98 and TA100. Antimutagenic activity was reported with inhibition of mutagenicity in a concentration dependent fashion. The methanolic extract demonstrated antioxidant activity in the DPPH radical-scavenging test (IC50 = 4.57 mg/mL), comparable to ascorbic acid and BHT. Moreover, the extract presented a remarkable and potent inhibition against soybean lipoxygenase (IC50 = 641.57 µg/mL). The methanolic extract was examined for its antimicrobial powers against four different bacteria with MIC values >100. Our results introduced this plant as a useful factor for the treatment of cancer, inflammatory and infectious diseases.

  20. In vitro Antimicrobial Activity ofCitrus aurantifolia and its Phytochemical screening

    Directory of Open Access Journals (Sweden)

    Rafi khan Pathan

    2012-05-01

    Full Text Available Objective: To evaluate the antimicrobial efficacy of Citrus aurantifolia Linn (CA against some microorganisms - bacteria and fungus were Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Pseudomonas spp, Aspergillus niger, Aspergillus fumigates, Mucor spp and Pencillium. Methods: 100 毺 l of 10 mg CA were assessed against eight test microorganisms by agar well Diffusion Method. Gentamicin and Ketoconazole 10 mg/ml were used as standards. A different solvent was used to obtain CA leaf extract by using maceration technique. Results: %yield obtained for dried leaf extract of CA with chloroform, ethanol, acetone, petroleum ether and aqueous ethanol was approximately 15%, 18%, 09%, 11% and 24% respectively. Due to its high yield value hydroalcoholic extract of CA was used for estimating the antimicrobial activity and its phytochemical screening. Phytochemical screening of CA plant reveals the presence of Alkaloids, carbohydrates, flavonoids, steroids and tannins. Conclusions: The study demonstrates that the hydroalcoholic extract of CA leaf exhibit antibacterial activity on Klebsiella pneumonia, Pseudomonas sp, Staphylococcus aureus and antifungal activity among Aspergillus niger, Aspergillus fumigates, Mucor species. These recognized a good support to the use of this plant in herbal medicine and as base for the development of new drugs and phytomedicine.

  1. Antimicrobial Activity of Rhoeo discolor Phenolic Rich Extracts Determined by Flow Cytometry.

    Science.gov (United States)

    García-Varela, Rebeca; García-García, Rebeca M; Barba-Dávila, Bertha A; Fajardo-Ramírez, Oscar R; Serna-Saldívar, Sergio O; Cardineau, Guy A

    2015-10-14

    Traditional medicine has led to the discovery of important active substances used in several health-related areas. Phytochemicals in Rhoeo discolor extracts have proven to have important antimicrobial activity. In the present study, our group determined the antimicrobial effects of extracts of Rhoeo discolor, a plant commonly used in Mexico for both medicinal and ornamental purposes. We evaluated the in vitro activity of phenolic rich extracts against specifically chosen microorganisms of human health importance by measuring their susceptibility via agar-disc diffusion assay and flow cytometry: Gram-positive Listeria innocua and Streptococcus mutans, Gram-negative Escherichia coli and Pseudomonas aeruginosa, and lastly a fungal pathogen Candida albicans. Ten different extracts were tested in eight different doses on all the microorganisms. Analytical data revealed a high content of phenolic compounds. Both agar-disc diffusion assay and flow cytometry results demonstrated that Pseudomonas aeruginosa was the least affected by extract exposure. However, low doses of these extracts (predominantly polar), in a range from 1 to 4 μg/mL, did produce a statistically significant bacteriostatic and bactericidal effect on the rest of the microorganisms. These results suggest the addition of certain natural extracts from Rhoeo discolor could act as antibacterial and antimycotic drugs or additives for foods and cosmetics.

  2. Antimicrobial Activity of Rhoeo discolor Phenolic Rich Extracts Determined by Flow Cytometry

    Directory of Open Access Journals (Sweden)

    Rebeca García-Varela

    2015-10-01

    Full Text Available Traditional medicine has led to the discovery of important active substances used in several health-related areas. Phytochemicals in Rhoeo discolor extracts have proven to have important antimicrobial activity. In the present study, our group determined the antimicrobial effects of extracts of Rhoeo discolor, a plant commonly used in Mexico for both medicinal and ornamental purposes. We evaluated the in vitro activity of phenolic rich extracts against specifically chosen microorganisms of human health importance by measuring their susceptibility via agar-disc diffusion assay and flow cytometry: Gram-positive Listeria innocua and Streptococcus mutans, Gram-negative Escherichia coli and Pseudomonas aeruginosa, and lastly a fungal pathogen Candida albicans. Ten different extracts were tested in eight different doses on all the microorganisms. Analytical data revealed a high content of phenolic compounds. Both agar-disc diffusion assay and flow cytometry results demonstrated that Pseudomonas aeruginosa was the least affected by extract exposure. However, low doses of these extracts (predominantly polar, in a range from 1 to 4 μg/mL, did produce a statistically significant bacteriostatic and bactericidal effect on the rest of the microorganisms. These results suggest the addition of certain natural extracts from Rhoeo discolor could act as antibacterial and antimycotic drugs or additives for foods and cosmetics.

  3. Antimicrobial resistance challenged with metal-based antimicrobial macromolecules.

    Science.gov (United States)

    Abd-El-Aziz, Alaa S; Agatemor, Christian; Etkin, Nola

    2017-02-01

    Antimicrobial resistance threatens the achievements of science and medicine, as it deactivates conventional antimicrobial therapeutics. Scientists respond to the threat by developing new antimicrobial platforms to prevent and treat infections from these resistant strains. Metal-based antimicrobial macromolecules are emerging as an alternative to conventional platforms because they combine multiple mechanisms of action into one platform due to the distinctive properties of metals. For example, metals interact with intracellular proteins and enzymes, and catalyse various intracellular processes. The macromolecular architecture offers a means to enhance antimicrobial activity since several antimicrobial moieties can be conjugated to the scaffold. Further, these macromolecules can be fabricated into antimicrobial materials for contact-killing medical implants, fabrics, and devices. As volatilization or leaching out of the antimicrobial moieties from the macromolecular scaffold is reduced, these medical implants, fabrics, and devices can retain their antimicrobial activity over an extended period. Recent advances demonstrate the potential of metal-based antimicrobial macromolecules as effective platforms that prevent and treat infections from resistant strains. In this review these advances are thoroughly discussed within the context of examples of metal-based antimicrobial macromolecules, their mechanisms of action and biocompatibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Egyptian propolis: 1-antimicrobial activity and chemical composition of Upper Egypt propolis.

    Science.gov (United States)

    Hegazi, A G; El Hady, F K

    2001-01-01

    The antimicrobial activity of four propolis samples collected from Upper Egypt against Staphylococcus aureus; Escherichia coli and Candida albicans was evaluated. There was a variation in the antimicrobial activity according to the propolis origin. Banisweif propolis showed the highest antimicrobial activity against Staphylococcus aureus, Escherichia coli and Candida albicans, but Fayoum propolis had moderate activity against all tested pathogens. Propolis collected from Assiut and Souhag gave lower antimicrobial activity. Propolis samples were investigated by GC/MS, 71 compounds were identified, 14 being new for propolis. Banisweif propolis is characterized by the presence of 7 caffeate esters and 4 triterpenoids. Fayoum propolis showed the highest amount of lactic acid and the presence of 3 chalcones. But Assiut propolis is characterized by the presence of 4 prenylated coumarates. Souhag propolis is characterized by the presence of 5 aliphatic dicarboxylic acids and some other new compounds to propolis.

  5. Antimicrobial activity of GN peptides and their mode of action

    DEFF Research Database (Denmark)

    Godballe, Troels; Mojsoska, Biljana; Nielsen, Hanne M

    2015-01-01

    Increasing prevalence of bacteria that carries resistance towards conventional antibiotics has prompted the investigation into new compounds for bacterial intervention to ensure efficient infection control in the future. One group of potential lead structures for antibiotics is antimicrobial pept...

  6. antimicrobial and antioxidant activities of some nigerian medicinal ...

    African Journals Online (AJOL)

    Prof. Clement Adewunmi

    Key words: Antimicrobial, antifungal, antioxidant properties, Nigerian medicinal ... This screening is of significant importance because of ... Materials and methods ...... Tsuda T. (1998) Dietary cyanidin 3-0-beta-D-glucoside increases ex vivo ...

  7. Nanocomposites of polymers with layered inorganic nanofillers: Antimicrobial activity, thermo-mechanical properties, morphology, and dispersion

    Science.gov (United States)

    Songtipya, Ponusa

    In the first part of the thesis, polyethylene/layered silicate nanocomposites that exhibit an antimicrobial activity were synthesized and studied. Their antimicrobial activity was designed to originate from non-leaching, novel cationic modifiers---amine-based surfactants---used as the organic-modification of the fillers. Specifically, PE/organically-modified montmorillonite ( mmt) nanocomposites were prepared via melt-processing, and simultaneous dispersion and antimicrobial activity was designed by proper choice of the fillers' organic modification. The antimicrobial activity was measured against three micotoxinogen fungal strains (Penicillium roqueforti and claviforme, and Fusarium graminearum ). Various mmt-based organofillers, which only differ in the type or amount of their organic modification, were used to exemplify how these surfactants can be designed to render antifungal activity to the fillers themselves and the respective nanocomposites. A comparative discussion of the growth of fungi on unfilled PE and nanocomposite PE films is used to demonstrate how the antimicrobial efficacy is dictated by the surfactant chemistry and, further, how the nanocomposites' inhibitory activity compares to that of the organo-fillers and the surfactants. An attempt to improve the thermomechanical reinforcement of PE/mmt nanocomposites while maintaining their antimicrobial activity, was also carried out by combining two different organically modified montmorillonites. However, a uniform microscopic dispersion could not be achieved through this approach. In the second part of this thesis, a number of fundamental studies relating to structure-property relations in nanocomposites were carried out, towards unveiling strategies that can concurrently optimize selected properties of polymers by the addition of nanofillers. Specifically, the dispersion-crystallinity-reinforcement relations in HDPE/mmt nanocomposites was investigated. The influence of a functional HDPE compatibilizer

  8. Screening antimicrobial activity of various extracts of Urtica dioica

    Directory of Open Access Journals (Sweden)

    Amir Modarresi-Chahardehi

    2012-12-01

    Full Text Available Urtica dioica or stinging nettle is traditionally used as an herbal medicine in Western Asia. The current study represents the investigation of antimicrobial activity of U. dioica from nine crude extracts that were prepared using different organic solvents, obtained from two extraction methods: the Soxhlet extractor (Method I, which included the use of four solvents with ethyl acetate and hexane, or the sequential partitions (Method II with a five solvent system (butanol. The antibacterial and antifungal activities of crude extracts were tested against 28 bacteria, three yeast strains and seven fungal isolates by the disc diffusion and broth dilution methods. Amoxicillin was used as positive control for bacteria strains, vancomycin for Streptococcus sp., miconazole nitrate (30µg/mL as positive control for fungi and yeast, and pure methanol (v/v as negative control. The disc diffusion assay was used to determine the sensitivity of the samples, whilst the broth dilution method was used for the determination of the minimal inhibition concentration (MIC. The ethyl acetate and hexane extract from extraction method I (EA I and HE I exhibited highest inhibition against some pathogenic bacteria such as Bacillus cereus, MRSA and Vibrio parahaemolyticus. A selection of extracts that showed some activity was further tested for the MIC and minimal bactericidal concentrations (MBC. MIC values of Bacillus subtilis and Methicillin-resistant Staphylococcus aureus (MRSA using butanol extract of extraction method II (BE II were 8.33 and 16.33mg/mL, respectively; while the MIC value using ethyl acetate extract of extraction method II (EAE II for Vibrio parahaemolyticus was 0.13mg/mL. Our study showed that 47.06% of extracts inhibited Gram-negative (8 out of 17, and 63.63% of extracts also inhibited Gram-positive bacteria (7 out of 11; besides, statistically the frequency of antimicrobial activity was 13.45% (35 out of 342 which in this among 21.71% belongs to

  9. The in vitro Antimicrobial Activity and Chemometric Modelling of 59 Commercial Essential Oils against Pathogens of Dermatological Relevance.

    Science.gov (United States)

    Orchard, Ané; Sandasi, Maxleene; Kamatou, Guy; Viljoen, Alvaro; van Vuuren, Sandy

    2017-01-01

    This study reports on the inhibitory concentration of 59 commercial essential oils recommended for dermatological conditions, and identifies putative compounds responsible for antimicrobial activity. Essential oils were investigated for antimicrobial activity using minimum inhibitory concentration assays. Ten essential oils were identified as having superior antimicrobial activity. The essential oil compositions were determined using gas chromatography coupled to mass spectrometry and the data analysed with the antimicrobial activity using multivariate tools. Orthogonal projections to latent structures models were created for seven of the pathogens. Eugenol was identified as the main biomarker responsible for antimicrobial activity in the majority of the essential oils. The essential oils mostly displayed noteworthy antimicrobial activity, with five oils displaying broad-spectrum activity against the 13 tested micro-organisms. The antimicrobial efficacies of the essential oils highlight their potential in treating dermatological infections and through chemometric modelling, bioactive volatiles have been identified.

  10. Antimicrobial, Antioxidant, and Anticancer Activities of Biosynthesized Silver Nanoparticles Using Marine Algae Ecklonia cava.

    Science.gov (United States)

    Venkatesan, Jayachandran; Kim, Se-Kwon; Shim, Min Suk

    2016-12-06

    Green synthesis of silver nanoparticles (AgNPs) has gained great interest as a simple and eco-friendly alternative to conventional chemical methods. In this study, AgNPs were synthesized by using extracts of marine algae Ecklonia cava as reducing and capping agents. The formation of AgNPs using aqueous extract of Ecklonia cava was confirmed visually by color change and their surface plasmon resonance peak at 418 nm, measured by UV-visible spectroscopy. The size, shape, and morphology of the biosynthesized AgNPs were observed by transmission electron microscopy and dynamic light scattering analysis. The biosynthesized AgNPs were nearly spherical in shape with an average size around 43 nm. Fourier transform-infrared spectroscopy (FTIR) analysis confirmed the presence of phenolic compounds in the aqueous extract of Ecklonia cava as reducing and capping agents. X-ray diffraction (XRD) analysis was also carried out to demonstrate the crystalline nature of the biosynthesized AgNPs. Antimicrobial results determined by an agar well diffusion assay demonstrated a significant antibacterial activity of the AgNPs against Escherichia coli and Staphylococcus aureus. Antioxidant results determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay revealed an efficient antioxidant activity of the biosynthesized AgNPs. The biosynthesized AgNPs also exhibited a strong apoptotic anticancer activity against human cervical cancer cells. Our findings demonstrate that aqueous extract of Ecklonia cava is an effective reducing agent for green synthesis of AgNPs with efficient antimicrobial, antioxidant, and anticancer activities.

  11. Antimicrobial activity screening of isolated flavonoids from Azadirachta indica leaves

    Directory of Open Access Journals (Sweden)

    QUDSIA KANWAL

    2011-03-01

    Full Text Available The antimicrobial activities of two flavonoids, namely genistein 7-O-glucoside (1 and (–-epi-catechin (2, isolated from Azadirachta indica A. Juss (neem leaves, were evaluated against five fungal species, viz: Alternaria alternata (Fr. Keissler, Aspergillus fumigatus Fresenius, Aspergillus niger van Tieghem, Macrophomina phaseolina (Tassi Goid. and Penicillium citrii, and four bacterial species, viz. Lactobacillus sp., Escherichia coli, Azospirillium lipoferum and Bacillus sp. Six concentrations, viz. 100, 300, 500, 700, 900 and 1000 ppm of each of the two flavonoids were employed using malt extract agar medium. All the concentrations of both the test compounds significantly suppressed fungal as well as bacterial growth. The highest concentration (1000 ppm of both fractions 1 and 2 reduced the growth of the different test fungal species by 83–99 % and 82–95 %, respectively. Compound 1 was highly effective against Lactobacillus sp., against which its various concentrations reduced the bacterial growth by 52–99.8 %. Compound 2 was highly effective against A. lipoferum and Bacillus sp., resulting in 94–100 % and 73–99% reduction in bacterial growth, respectively.

  12. Synthesis, Reactions and Antimicrobial Activities of 8-Ethoxycoumarin Derivatives

    Directory of Open Access Journals (Sweden)

    Mostafa M. Khafagy

    2012-01-01

    Full Text Available Condensation of 3-acetyl-8-ethoxycoumarin (3 with thiosemicarbazide gave ethylidenehydrazinecarbothioamide 5, which was transformed into the thiazolidin-4-one derivatives 6,7. Interaction of 3 with DMF/POCl3 gave b-chloroacroline derivative 8. Treatment of 3 with malononitrile gave benzo[c]chromone and 2-aminobenzonitrile derivatives 9 and 10, respectively with respect to the reaction conditions. Condensation of 3-(2-bromoacetyl-8-ethoxycoumarin (4 with o-phenylenediamine gave 3-(quioxaline-2-yl-8-ethoxycoumarin hydrobromide (11, while 4 reacted with 2-aminopyridine to give chromenopyridopyrimidine derivative 12. Condensation of 4 with potassium thio-cyanate/methanol gave an unexpected derivative, 2H-chromeno-3-carboxy(methyl-carbonimidicthioanhydride 16, which upon treatment with (NH22·H2O gave 3-ethoxy-2-hydroxybenzaldehyde azine 19. Interaction of 4 with thiourea derivatives gave thiazole derivatives 20a–c. The structures of the newly synthesized compounds were confirmed by their spectra data. The newly synthesized compounds were also screened for their antimicrobial activity.

  13. Synthesis and Antimicrobial Activities of Some Novel Quinoxalinone Derivatives

    Directory of Open Access Journals (Sweden)

    Y. A. Ammar

    2000-06-01

    Full Text Available Condensation of 4-benzoyl-1,2-phenylenediamine with sodium pyruvate in acetic acid furnished two products which were identified as 6-benzoyl and 7-benzoyl-3-methyl-2(1Hquinoxalinones (1a,b. Fusion of 1a with aromatic aldehydes furnished the styryl derivatives 2a-c. Alkylation of 1a,b with dimethyl sulphate or ethyl chloroacetate produced the N-alkyl derivatives 3a,b and 4a,b. Hydrazinolysis of the ester derivative 4a with hydrazine hydrate afforded the hydrazide derivative 5 which underwent condensation with aldehydes to give the corresponding hydrazone derivatives 6a,b. In addition, chlorination of 1a with thionyl chloride afforded the 2-chloro derivative 7 which was subjected to reaction with sodium azide and n-butylamine to yield the corresponding tetrazolo (8 and n-butylamino (9 derivatives, respectively. The structures of the compounds prepared were confirmed by analytical and spectral data. Also, some of the synthesized compounds were screened for antimicrobial activity.

  14. Synthesis and antimicrobial activity of gold nanoparticle conjugates with cefotaxime

    Science.gov (United States)

    Titanova, Elena O.; Burygin, Gennady L.

    2016-04-01

    Gold nanoparticles (GNPs) have attracted significant interest as a novel platform for various applications to nanobiotechnology and biomedicine. The conjugates of GNPs with antibiotics and antibodies were also used for selective photothermal killing of protozoa and bacteria. Also the conjugates of some antibiotics with GNPs decreased the number of bacterial growing cells. In this work was made the procedure optimization for conjugation of cefotaxime (a third-generation cephalosporin antibiotic) with GNPs (15 nm) and we examined the antimicrobial properties of this conjugate to bacteria culture of E. coli K-12. Addition of cefotaxime solution to colloidal gold does not change their color and extinction spectrum. For physiologically active concentration of cefotaxime (3 μg/mL), it was shown that the optimum pH for the conjugation was more than 9.5. A partial aggregation of the GNPs in saline medium was observed at pH 6.5-7.5. The optimum concentration of K2CO3 for conjugation cefotaxime with GNPs-15 was 5 mM. The optimum concentration of cefotaxime was at 0.36 μg/mL. We found the inhibition of the growth of E. coli K12 upon application cefotaxime-GNP conjugates.

  15. Novel 2-Thioxanthine and Dipyrimidopyridine Derivatives: Synthesis and Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Samar El-kalyoubi

    2015-10-01

    Full Text Available Several fused imidazolopyrimidines were synthesized starting from 6-amino-1-methyl-2-thiouracil (1 followed by nitrosation, reduction and condensation with different aromatic aldehydes to give Schiff’s base. The dehydrocyclization of Schiff’s bases using iodine/DMF gave Compounds 5a–g. The methylation of 5a–g using a simple alkylating agent as dimethyl sulfate ((CH32SO4 gave either monoalkylated imidazolopyrimidine 6a–g at room temperature or dialkylated derivatives 7a–g on heating 6a–g with ((CH32SO4. On the other hand, treatment of 1 with different aromatic aldehydes in absolute ethanol in the presence of conc. hydrochloric acid at room temperature and/or reflux with acetic acid afforded bis-5,5́-diuracylmethylene 8a–e, which cyclized on heating with a mixture of acetic acid/HCl (1:1 to give 9a–e. Compounds 9a–e can be obtained directly by refluxing of Compound 1 with a mixture of acetic acid/HCl. The synthesized new compounds were screened for antimicrobial activity, and the MIC was measured.

  16. Assessing the Antimicrobial Activity of Polyisoprene Based Surfaces

    Directory of Open Access Journals (Sweden)

    Hope Badawy

    2015-02-01

    Full Text Available There has been an intense research effort in the last decades in the field of biofouling prevention as it concerns many aspects of everyday life and causes problems to devices, the environment, and human health. Many different antifouling and antimicrobial materials have been developed to struggle against bacteria and other micro- and macro-organism attachment to different surfaces. However the “miracle solution” has still to be found. The research presented here concerns the synthesis of bio-based polymeric materials and the biological tests that showed their antifouling and, at the same time, antibacterial activity. The raw material used for the coating synthesis was natural rubber. The polyisoprene chains were fragmented to obtain oligomers, which had reactive chemical groups at their chain ends, therefore they could be modified to insert polymerizable and biocidal groups. Films were obtained by radical photopolymerization of the natural rubber derived oligomers and their structure was altered, in order to understand the mechanism of attachment inhibition and to increase the efficiency of the anti-biofouling action. The adhesion of three species of pathogenic bacteria and six strains of marine bacteria was studied. The coatings were able to inhibit bacterial attachment by contact, as it was verified that no detectable leaching of toxic molecules occurred.

  17. In Vitro Antimicrobial Activity of Iris pseudacorus and Urtica dioica

    Directory of Open Access Journals (Sweden)

    Maryam Ramtin

    2014-03-01

    Full Text Available Background: In this study, the effects of antibacterial activity of Urtica dioica and Iris pseudacorus essential oils, native plant northern of Iran, were investigated for some selected bacteria. Material and Methods: The influence of essential oils was tested by the using of disk diffusion and micro-broth dilution methods against standard strains of the picked out bacteria. Gas Chromatography/Mass Spectroscopy (GC/MS analysis, bioactivity determination, Minimum inhibitory concentrations (MIC and minimum bactericidal concentration (MBC of essential oils were utilized for this goal. Results: This study showed that, Inhibition zone diameter varied from 11 to 19 mm and 9 to 17 mm for Urtica dioica and Iris pseudacorus respectively. In contrast, this figure fluctuated from 19 to 28 mm and 7 to 17 mm for gentamicin and ampicillin separately. By the application of micro-broth dilution technique, MICs for 1% essential oils were 1.8-7.5 μg/ml and 3.75-15 μg/ml for, Urtica dioica and Iris pseudacorus against gram-positive and gram-negative bacteria individually. Furthermore, the MBCs of herbal essences were 1.8-15 μg/ml for, Urtica dioica and 15-30 μg/ml for Iris. Conclusion: The application of essential oils for the bio-control of diseases, as a novel emerging alternative to antimicrobial treatments, lead to safer and more environmental management for infective diseases4T.4T

  18. The antimicrobial activity of Liquidambar orientalis mill. against food pathogens and antioxidant capacity of leaf extracts.

    Science.gov (United States)

    Okmen, G; Turkcan, O; Ceylan, O; Gork, G

    2014-01-01

    Medicinal plants are an important source of substances which are claimed to induce antimicrobial, antimutagenic and antioxidant effects. Many plants have been used due to their antimicrobial treatments. Antimicrobial and antioxidant activities of L. orientalis have not been reported to the present day. The aim of this work was to investigate of the antimicrobial and antioxidant potentials of different extracts from L. orientalis. The extracts were screened for antimicrobial activity against different food pathogens. These bacteria include 4 Gram positive and 3 Gram negative bacteria and one fungi. The leaf extracts of plant were tested by disc diffusion assay. The MIC was evaluated on plant extracts as antimicrobial activity. In addition to, the plant extracts were tested against the stable DPPH (2,2-diphenyl-1-picryl-hydrazylhydrate) free-radical. The acetone, ethanol and methanol extracts of L. orientalis showed maximum inhibition zone of 12 mm against Yersinia enterocolitica, Listeria monocytogenes and Staphylococcus aureus. In addition to, the methanol extract displayed a strong antioxidant activity (trolox equivalent = 2.23 mM). L. orientalis extracts have antimicrobial, and antioxidant potential. Our results support the use of this plant in traditional medicine and suggest that some of the plant extracts possess compounds with good antibacterial properties that can be used as antibacterial agents in the search for new drugs.

  19. Antimicrobial activities of the rhizome extract of Zingiber zerumbet Linn

    Institute of Scientific and Technical Information of China (English)

    Golam Kader; Farjana Nikkon; Mohammad Abdur Rashid; Tanzima Yeasmin

    2011-01-01

    Objective: To investigate antimicrobial effects of ethanolic extract of Zingiber zerumbet (Z. zerumbet) (L.) Smith and its chloroform and petroleum ether soluble fractions against pathogenic bacteria and fungi. Methods: The fresh rhizomes of Zingiber zerumbet were extracted in cold with ethanol (4.0 L) after concentration. The crude ethanol extract was fractionated by petroleum ether and chloroform to form a suspension of ethanol extract (15.0 g), petroleum ether fraction (6.6 g) and chloroform soluble fraction (5.0 g). The crude ethanol extract and its petroleum ether and chloroform fractions were evaluated for antibacterial and antifungal activity against thirteen pathogenic bacteria and three fungi by the disc diffusion method. Commercially available kanamycin (30 μg/disc) was used as standard disc and blank discs impregnated with the respective solvents were used as negative control. Results: At a concentration of 400 μg/disc, all the samples showed mild to moderate antibacterial and antifungal activity and produced the zone of inhibition ranging from 6 mm to 10 mm. Among the tested samples, the crude ethanol extract showed the highest activity against Vibrio parahemolyticus (V. parahemolyticus). The minimum inhibitory concentration (MIC) of the crude ethanol extract and its fractions were within the value of 128-256 μg/mL against two Gram positive and four Gram negative bacteria and all the samples showed the lowest MIC value against V. parahemolyticus (128 μg/mL). Conclusions: It can be concluded that, potent antibacterial and antifungal phytochemicals are present in ethanol extract of Z. zerumbet (L).

  20. Antioxidant, antiproliferative and antimicrobial activity of freeze-dried raspberry

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    Vulić Jelena J.

    2014-01-01

    Full Text Available The main chemical composition, i.e. the total content of bioactive compounds (phenolics 2209.86 ± 70.32 mg GAE/100g FDR, flavonoids 831.87 ± 12.61 mg R/100g FDR and anthocyanins 144.55 ± 0.39 mg CGE/100g FDR, in freeze-dried raspberry (FDR was evaluated spectrophotometrically. Vitamin C content was determined by HPLC analysis (88.81 ± 4.38 mg vit C/100g FDR. Antioxidant activities of FDR extract were evaluated spectrophotometrically on stable 2,2-diphenyl-1-picrylhydrazyl (DPPH free radicals and by electron spin resonance spectroscopy (ESR method on hydroxyl radicals (•OH. EC50 values were evaluated. EC50 DPPH• was 0.127 ± 0.013 mg/ml, while EC50 •OH was 1.366 ± 0.026 mg/ml. Antiproliferative activity of the FDR extract was evaluated in vitro in three human cell lines by colorimetric sulphorhodamine B (SRB assay. The most pronounced effects were obtained in the breast adenocarcinoma cell line (MCF7. EC50 value was 395.07 ± 96.38 μg/ml. Antimicrobial activity was determined by disk diffusion method. The FDR extract produced a clear inhibition zone (without visible colonies only toward Staphylococcus aureus. The minimal inhibitory (MIC and minimal bactericidal (MBC concentrations of FDR extract were evaluated. The values MIC were in the range of 4.7 - 100 mg/ml, and of MBC in the range of 6.3 - > 100 mg/ml.[ Projekat Ministarstva nauke Republike Srbije, br. TR 31044

  1. Position-Dependent Influence of the Three Trp Residues on the Membrane Activity of the Antimicrobial Peptide, Tritrpticin

    Directory of Open Access Journals (Sweden)

    Mauricio Arias

    2014-11-01

    Full Text Available Antimicrobial peptides (AMPs constitute promising candidates for the development of new antibiotics. Among the ever-expanding family of AMPs, tritrpticin has strong antimicrobial activity against a broad range of pathogens. This 13-residue peptide has an unusual amino acid sequence that is almost symmetrical and features three central Trp residues with two Arg residues near each end of the peptide. In this work, the role of the three sequential Trp residues in tritrpticin was studied in a systematic fashion by making a series of synthetic peptides with single-, double- and triple-Trp substitutions to Tyr or Ala. 1H NMR and fluorescence spectroscopy demonstrated the ability of all of the tritrpticin-analog peptides to interact with negatively-charged membranes. Consequently, most tritrpticin analogs exhibited the ability to permeabilize synthetic ePC:ePG (egg-yolk phosphatidylcholine (ePC, egg-yolk phosphatidylglycerol (ePG vesicles and live Escherichia coli bacteria. The membrane perturbation characteristics were highly dependent on the location of the Trp residue substitution, with Trp6 being the most important residue and Trp8 the least. The membrane permeabilization activity of the peptides in synthetic and biological membranes was directly correlated with the antimicrobial potency of the peptides against E. coli. These results contribute to the understanding of the role of each of the three Trp residues to the antimicrobial activity of tritrpticin.

  2. Investigation on antimicrobial activity and phytochemical screening ofRandia spinosa (Thunb.) Poir. and Dillenia pentagyna Roxb

    Institute of Scientific and Technical Information of China (English)

    Irulandi Kokkaiah; Geetha Sethupandian; Mehalingam Palanichamy

    2016-01-01

    Objective:To evaluate phytochemicals and antimicrobial activity ofRandia spinosa (Thunb.) Poir. andDillenia pentagyna Roxb. leaf extracts against human pathogens such as Gram positive bacteria (Streptococcus faecalis,Bacillus subtilis andStaphyllococcus aureus), Gram negative bacteria (Escherichia coli,Klebsiella pneumoniae andPseudomonas aeruginosa), and a fungusCandida albicans. Methods: Antimicrobial activity of methanol, acetone and ethyl acetate extracts of the two plants against the human pathogens was investigated by agar well diffusion method, and qualitative phytochemical screening was conducted for the presence of phytoconstituents such as alkaloids, catechins, coumarins, flavonoids, phenols, quinones, saponins, steroids, tannins and terpenoids. Results: The qualitative phytochemical analysis showed the presence of diverse range of compounds like alkaloids, flavonoids, phenols, steroids, tannins, terpenoids and saponins. The plants exhibited broad spectrum of antimicrobial activities against all the tested bacterial and fungal pathogens. The maximum zone of inhibition was observed in methanol extracts when compared with acetone and ethyl acetate extracts. The present study demonstrated that the selected plants had promising effect on the bacterial and fungal pathogens. Conclusions: The phytochemicals in the plants may be potentially responsible for the antimicrobial efficacy of these medicinal plants.

  3. Synthesis, characterization, antimicrobial activity and LPS-interaction properties of SB041, a novel dendrimeric peptide with antimicrobial properties.

    Science.gov (United States)

    Bruschi, Michela; Pirri, Giovanna; Giuliani, Andrea; Nicoletto, Silvia Fabiole; Baster, Izabela; Scorciapino, Mariano Andrea; Casu, Mariano; Rinaldi, Andrea C

    2010-08-01

    Multimeric peptides offer several advantages with respect to their monomeric counterparts, as increased activity and greater stability to peptidases and proteases. SB041 is a novel antimicrobial peptide with dendrimeric structure; it is a tetramer of pyrEKKIRVRLSA linked by a lysine core, with an amino valeric acid chain. Here, we report on its synthesis, NMR characterization, antimicrobial activity, and LPS-interaction properties. The peptide was especially active against Gram-negative strains, with a potency comparable (on molar basis) to that of lipopeptides colistin and polymixin B, but it also displayed some activity against selected Gram-positive strains. Following these indications, we investigated the efficacy of SB041 in binding Escherichia coli and Pseudomonas aeruginosa LPS in vitro and counteracting its biological effects in RAW-Blue cells, derived from RAW 264.7 macrophages. SB041 strongly bound purified LPS, especially that of E. coli, as proved by fluorescent displacement assay, and readily penetrated into LPS monolayers. However, the killing activity of SB041 against E. coli was not inhibited by increasing concentrations of LPS added to the medium. Checking the SB041 effect on LPS-induced activation of pattern recognition receptors (PRRs) in Raw-Blue cells revealed that while the peptide gave a statistically significant decrease in PRRs stimulation when RAW-Blue cells were challenged with P. aeruginosa LPS, the same was not seen when E. coli LPS was used to activate innate immune defense-like responses. Thus, as previously seen for other antimicrobial peptides, also for SB041 binding to LPS did not translate necessarily into LPS-neutralizing activity, suggesting that SB041-LPS interactions must be of complex nature.

  4. Electrospun mats from styrene/maleic anhydride copolymers: modification with amines and assessment of antimicrobial activity.

    Science.gov (United States)

    Ignatova, Milena; Stoilova, Olya; Manolova, Nevena; Markova, Nadya; Rashkov, Iliya

    2010-08-11

    New antimicrobial microfibrous electrospun mats from styrene/maleic anhydride copolymers were prepared. Two approaches were applied: (i) grafting of poly(propylene glycol) monoamine (Jeffamine® M-600) on the mats followed by formation of complex with iodine; (ii) modification of the mats with amines of 8-hydroxyquinoline or biguanide type with antimicrobial activity. Microbiological screening against S. aureus, E. coli and C. albicans revealed that both the formation of complex with iodine and the covalent attachment of 5-amino-8-hydroxyquinoline or of chlorhexidine impart high antimicrobial activity to the mats. In addition, S. aureus bacteria did not adhere to modified mats.

  5. Purification and in vitro Activity of an Antimicrobial Peptide from Skin of Rana Temporaria Chensinensis, David

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jie; MENG Qing-fan; XU Xue-song; TIAN Xiao-le; JIANG Fu-jia; LI Qing-shan; TENG Li-rong

    2007-01-01

    In this study, an antimicrobial component (RTCI) was purified from the skin of Rana temporaria chensinensis,David. Antimicrobial activities of RTCI against clinical multi-drug resistant bacterial strains, including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureaus, Klebsiella oxytoca, Klebsiella pneumoniae, Enterococcus faecalis, and Proteus mirabilis were measured in vitro by means of minimal inhibitory concentration and time-kill studies.The results indicate that RTCI could inhibit the growth of these bacteria at a proper concentration and suggest that RTCI shows a better antimicrobial activity to Gram-negative bacterial strains than to Gram-positive bacterial strains.

  6. Antimicrobial Activity of Ferulic Acid Against Cronobacter sakazakii and Possible Mechanism of Action.

    Science.gov (United States)

    Shi, Chao; Zhang, Xiaorong; Sun, Yi; Yang, Miaochun; Song, Kaikuo; Zheng, Zhiwei; Chen, Yifei; Liu, Xin; Jia, Zhenyu; Dong, Rui; Cui, Lu; Xia, Xiaodong

    2016-04-01

    Cronobacter sakazakii is an opportunistic pathogen transmitted by food that affects mainly newborns, infants, and immune-compromised adults. In this study, the antibacterial activity of ferulic acid was tested against C. sakazakii strains. Minimum inhibitory concentration of ferulic acid against C. sakazakii strains was determined using the agar dilution method. Changes in intracellular pH, membrane potential and intracellular ATP concentration were measured to elucidate the possible antibacterial mechanism. Moreover, SYTO 9 nucleic acid staining was used to assess the effect of ferulic acid on bacterial membrane integrity. Cell morphology changes were observed under a field emission scanning electron microscope. The minimum inhibitory concentrations of ferulic acid against C. sakazakii strains ranged from 2.5 to 5.0 mg/mL. Addition of ferulic acid exerted an immediate and sustained inhibition of C. sakazakii proliferation. Ferulic acid affected the membrane integrity of C. sakazakii, as evidenced by intracellular ATP concentration decrease. Moreover, reduction of intracellular pH and cell membrane hyperpolarization were detected in C. sakazakii after exposure to ferulic acid. Reduction of green fluorescence indicated the injury of cell membrane. Electronic microscopy confirmed that cell membrane of C. sakazakii was damaged by ferulic acid. Our results demonstrate that ferulic acid has moderate antimicrobial activity against C. sakazakii. It exerts its antimicrobial action partly through causing cell membrane dysfunction and changes in cellular morphology. Considering its antimicrobial properties, together with its well-known nutritional functions, ferulic acid has potential to be developed as a supplement in infant formula or other foods to control C. sakazakii.

  7. Antimicrobial activity, toxicity and stability of phytol as a novel surface disinfectant

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Ghaneian

    2015-01-01

    Full Text Available Background: Although various surface disinfectants have been introduced, most of them are toxic. The use of natural antimicrobial agent e.g. phytol, extracted from Leptadeniapyrotechnicais a new strategy. The aim of this study was to evaluate the antimicrobial activity, toxicity, and stability of phytol. Methods: The serial concentrations of phytol were prepared, and separately incubated with four microbial isolates. Then, its Minimum Inhibitory Concentration (MIC was measured for each microorganism. For toxicity test, serial concentrations (62.5, 125, 250, 500 and 1000 μg/mL of phytol were incubated with mouse skin cells, and then cell viability was calculated by MTT assay. For stability test, three common surfaces (stone, steel, and MDF were considered. Then, 100 μL of phytol was separately spread over their surface, and they have been kept at lab panel for 12, 24 and 36 hours. After incubation, two samples were obtained from each surface and inoculated on nutrient agar plates. Finally, colony count was read for each surface. T-test was used to evaluate the significant differences between groups, and P>0.05 considered as level of significant difference. Results: The MIC50 of phytol against E.coli, C.albicans, and A.nigerwas 62.5 μg/mL, and against S.aureuswas >1000 μg/mL. MTT assay showed that the toxicity of phytol was dose and time dependent. The stability test demonstrated that phytol was stable on the stone, MDF, and steel surfaces until 36 hours. Conclusion: It can be concluded that phytol has high antimicrobial activity, high stability, and low toxicity. This substance must be evaluated at actual conditions.

  8. Screening for the presence of antimicrobial activity in few Indian seaweeds

    Digital Repository Service at National Institute of Oceanography (India)

    Kotnala, S.; Garg, Aakriti; Chatterji, A.

    Methanolic extracts of 17 commonly found seaweeds in the west coast of India were screened for the presence of antimicrobial activity against Bacillus subtilis, Escherichia coli, Pseudomonas sp., Streptococcus pyrogenes, Staphylococcus aureus...

  9. Antimicrobial Activity of Kedawung Extract (Parkia Roxburghii G. Don on Food Borne Pathogens

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    Ervizal A. M Zuhud, Winiati Pudji Rahayu, C. Hanny Wijaya, Pipi Puspita Sari

    2001-04-01

    Full Text Available Kedawung is a Leguminosae/Fabaceae which. It is commonly used as traditional medicine for infection and stomach disoders, caused by bacteria.The aim of this study is to examine the potential antimicrobial activity of seed, bark, root and kedawung leaf. It is expected that the result will give information on characteristics and concentration of kedawung part which have the highest antimicrobial activity.The result showed that the bark has the highest antimicrobial activity on Escherichia coli, Vibrio cholerae, Staphylococcus aureus and Bacillus cereus. Extract made from kedawung plant and water (ratio 1:2,b/v was better than those made with ratios of 1 : 1 or 1 : 3 (b/v. Heat did not decrease its antimicrobial activity. Extract concentration of 10% (21.40 mg/ml with contact time of 24 hour decreased bacterial growth but did not inactivate them.

  10. Antioxidant and antimicrobial activities of individual and combined phenolics in Olea europaea leaf extract.

    Science.gov (United States)

    Lee, Ok-Hwan; Lee, Boo-Yong

    2010-05-01

    Olive leaves, an agricultural waste, have great potential as a natural antioxidant. The current study was made to assess the antioxidant and antimicrobial activities of both the individual and combined phenolics in olive leaf extract. A combined phenolics mixture was prepared by amount ratios of the phenolic compounds in the olive leaf extract. The results showed that both the individual and combined phenolics exhibited good radical scavenging abilities, and also revealed superoxide dismutase (SOD)-like activity. In terms of antimicrobial activity, both oleuropein and caffeic acid showed inhibition effects against microorganisms. Furthermore, the antimicrobial effect of the combined phenolics was significantly higher than those of the individual phenolics. These results show that the combination of olive leaf extract phenolics possessed antioxidant and antimicrobial activities. This study indicates that olive leaf extract might be a valuable bioactive source, and would seem to be applicable in both the health and medical food.

  11. Retention of Antimicrobial Activity in Plaque and Saliva following Mouthrinse Use in vivo

    National Research Council Canada - National Science Library

    Otten, M. P. T; Busscher, H. J; van der Mei, H. C; Abbas, F; van Hoogmoed, C. G

    2010-01-01

    The aim of this study was to determine the contribution of plaque and saliva towards the prolonged activity, also called substantivity, of three antimicrobial mouthrinses (Listerine (R), Meridol (R), Crest Pro Health (R...

  12. Antitumor and angiostatic activities of the antimicrobial peptide dermaseptin B2

    National Research Council Canada - National Science Library

    van Zoggel, Hanneke; Carpentier, Gilles; Dos Santos, Célia; Hamma-Kourbali, Yamina; Courty, José; Amiche, Mohamed; Delbé, Jean

    2012-01-01

    ... as the antimicrobial peptide dermaseptin (Drs) B2. In the present study we further explored the in vitro and in vivo antitumor activity of this molecule and investigated its mechanism of action...

  13. Antimicrobial activity of Serratia sp isolated from the coralline red algae Amphiroa anceps

    Digital Repository Service at National Institute of Oceanography (India)

    Karthick, P.; Mohanraju, R.; Murthy, K.N.; Ramesh, Ch.; Mohandass, C.; Rajasabapathy, R.; Vellai, K.S.

    Bacterial isolates (6 nos) were obtained from the coralline red algae Amphiroa anceps Crude extract of these isolated were tested for antimicrobial activity against 20 different human pathogenic bacterial and fungal strains Among this crude extract...

  14. Antimicrobial activity of some actinomycetes from Western Ghats of Tamil Nadu, India

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    Pathalam Ganesan

    2017-06-01

    Conclusions: The present work revealed that, among 106 actinomycetes screened, Streptomyces rimosus (FMS-20 (Accession No-KT827106 showed promising antimicrobial activity against all the tested human microbial pathogens.

  15. Functional divergence among silkworm antimicrobial peptide paralogs by the activities of recombinant proteins and the induced expression profiles.

    Directory of Open Access Journals (Sweden)

    Wanying Yang

    Full Text Available Antimicrobial peptides are small-molecule proteins that are usually encoded by multiple-gene families. They play crucial roles in the innate immune response, but reports on the functional divergence of antimicrobial peptide gene families are rare. In this study, 14 paralogs of antimicrobial peptides belonging to cecropin, moricin and gloverin families were recombinantly expressed in pET expression systems. By antimicrobial activity tests, peptides representing paralogs in the same family of cecropin and moricin families, displayed remarkable differences against 10 tested bacteria. The evolutionary rates were relatively fast in the two families, which presented obvious functional divergence among paralogs of each family. Four peptides of gloverin family had similar antimicrobial spectrum and activity against tested bacteria. The gloverin family showed similar antimicrobial function and slow evolutionary rates. By induced transcriptional activity, genes encoding active antimicrobial peptides were upregulated at obviously different levels when silkworm pupae were infected by three types of microbes. Association analysis of antimicrobial activities and induced transcriptional activities indicated that the antimicrobial activities might be positively correlated with induced transcriptional activities in the cecropin and moricin families. These results suggest that representative BmcecB6, BmcecD and Bmmor as the major effector genes have broad antimicrobial spectrum, strong antimicrobial activity and high microbe-induced expression among each family and maybe play crucial roles in eliminating microbial infection.

  16. Silver sucrose octasulfate (IASOS™ as a valid active ingredient into a novel vaginal gel against human vaginal pathogens: in vitro antimicrobial activity assessment.

    Directory of Open Access Journals (Sweden)

    Cinzia Marianelli

    Full Text Available This in vitro study assessed the antimicrobial properties of a novel octasilver salt of Sucrose Octasulfate (IASOS as well as of an innovative vaginal gel containing IASOS (SilSOS Femme, against bacterial and yeast pathogens isolated from human clinical cases of symptomatic vaginal infections. In BHI and LAPT culture media, different ionic silver concentrations and different pHs were tested. IASOS exerted a strong antimicrobial activity towards all the pathogens tested in both culture media. The results demonstrated that salts and organic compounds present in the culture media influenced IASOS efficacy only to a moderate extent. Whereas comparable MBCs (Minimal Bactericidal Concentrations were observed for G. vaginalis (10 mg/L Ag+, E. coli and E. aerogenes (25 mg/L Ag+ in both media, higher MBCs were found for S. aureus and S. agalactiae in LAPT cultures (50 mg/L Ag+ versus 25 mg/L Ag+. No minimal concentration totally inhibiting the growth of C. albicans was found. Nevertheless, in both media at the highest ionic silver concentrations (50-200 mg/L Ag+, a significant 34-52% drop in Candida growth was observed. pH differently affected the antimicrobial properties of IASOS against bacteria or yeasts; however, a stronger antimicrobial activity at pH higher than the physiological pH was generally observed. It can be therefore concluded that IASOS exerts a bactericidal action against all the tested bacteria and a clear fungistatic action against C. albicans. The antimicrobial activity of the whole vaginal gel SilSOS Femme further confirmed the antimicrobial activity of IASOS. Overall, our findings support IASOS as a valid active ingredient into a vaginal gel.

  17. Oxygen limitation favors the production of protein with antimicrobial activity in Pseudoalteromonas sp

    Directory of Open Access Journals (Sweden)

    Ruth López

    2012-09-01

    Full Text Available This study examined the effect of dissolved oxygen concentration on the production of biomass and metabolites with antimicrobial activity of Pseudoalteromonas sp cultured at 0, 150, 250, or 450 revolutions per minute (rev. min-1. Dissolved oxygen (D.O was monitored during the fermentation process, biomass was quantified by dry weight, and antimicrobial activity was assessed using the disk diffusion method. The bacterium Pseudoalteromonas reached similar concentration of biomass under all experimental agitation conditions, whereas antimicrobial activity was detected at 0 and 150 rev. min-1 registering 0% and 12% of D.O respectively corresponding to microaerophilic conditions. Antibiotic activity was severely diminished when D.O was above 20% of saturation; this corresponded to 250 or 450 rev. min-1. SDS-PAGE electrophoresis revealed a protein with a molecular weight of approximately 80 kilodaltons (kDa with antimicrobial activity. Pseudoalteromonas is capable of growing under oxic and microaerophilic conditions but the metabolites with antimicrobial activity are induced under microaerophilic conditions. The current opinion is that Pseudoalteromonas are aerobic organisms; we provide additional information on the amount of dissolved oxygen during the fermentation process and its effect on antimicrobial activity.

  18. Evaluation of the flora of northern Mexico for in vitro antimicrobial and antituberculosis activity.

    Science.gov (United States)

    Molina-Salinas, G M; Pérez-López, A; Becerril-Montes, P; Salazar-Aranda, R; Said-Fernández, S; de Torres, N Waksman

    2007-02-12

    The aim of the present study was to evaluate the potential antimicrobial activity of 14 plants used in northeast México for the treatment of respiratory diseases, against drug-sensitive and drug-resistant strains of Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae type b and Mycobacterium tuberculosis. Forty-eight organic and aqueous extracts were tested against these bacterial strains using a broth microdilution test. No aqueous extracts showed antimicrobial activity, whereas most of the organic extracts presented antimicrobial activity against at least one of the drug-resistant microorganisms tested. Methanol-based extracts from the roots and leaves of Leucophyllum frutescens and ethyl ether extract from the roots of Chrysanctinia mexicana showed the greatest antimicrobial activity against the drug-resistant strain of Mycobacterium tuberculosis; the minimal inhibitory concentration (MIC) were 62.5, 125 and 62.5 microg/mL, respectively; methanol-based extract from the leaves of Cordia boissieri showed the best antimicrobial activity against the drug-resistant strain of Staphylococcus aureus (MIC 250 microg/mL); the hexane-based extract from the fruits of Schinus molle showed considerable antimicrobial activity against the drug-resistant strain of Streptococcus pneumoniae (MIC 62.5 microg/mL). This study supports that selecting plants by ethnobotanical criteria enhances the possibility of finding species with activity against resistant microorganisms.

  19. Alternative Hand Contamination Technique To Compare the Activities of Antimicrobial and Nonantimicrobial Soaps under Different Test Conditions▿

    OpenAIRE

    Fuls, Janice L.; Rodgers, Nancy D.; Fischler, George E.; Howard, Jeanne M.; Patel, Monica; Weidner, Patrick L.; Duran, Melani H.

    2008-01-01

    Antimicrobial hand soaps provide a greater bacterial reduction than nonantimicrobial soaps. However, the link between greater bacterial reduction and a reduction of disease has not been definitively demonstrated. Confounding factors, such as compliance, soap volume, and wash time, may all influence the outcomes of studies. The aim of this work was to examine the effects of wash time and soap volume on the relative activities and the subsequent transfer of bacteria to inanimate objects for ant...

  20. Multifunctional activities of KSLW synthetic antimicrobial decapeptide: Implications for wound healing

    Science.gov (United States)

    Williams, Richard Leroy

    Wound healing is a complex process leading to the maintenance of skin integrity. Stress is known to increase susceptibility to bacterial infection, alter proinflammatory cytokine expression, and delay wound closure. Recently, antimicrobial peptides have generated interest due to their prokaryotic selectivity, decreased microbial resistance and multifunctional roles in wound healing, including fibroblast stimulation, keratinocyte migration and leukocyte migration. The objective of this dissertation project was to evaluate the effect of a synthetic antimicrobial decapeptide (KSLW) on bacterial clearance inflammation, and wound closure during stress-impaired healing. SKH-1 mice were randomly assigned to either control or restraint-stressed (RST) groups. Punch biopsy wounds (3.5 mm in diameter) were created bilaterally on the dorsal skin. Wounds were injected with 50 microL of empty carriers or KSLW prepared in Pluronic-F68, phospholipid micelles, or saline. Bacterial assays of harvested wounds were conducted on BHI agar. Wound closure was determined by photoplanimetry. Cytokine and growth factor mRNA expression was assessed with real-time RT-PCR. Human neutrophil migration assays and checkerboard analyses were performed using Transweli plates, and counting on hemacytometer. Oxidative burst activity was measured by spectrophotometric analysis of 2,7-dichlorofluorescein oxidation. KSLW-treatment resulted in significant reductions in bacterial load among RST mice, with no difference from control after 24h. The effect was sustained 5 days post-wounding, in RST mice treated with KSLW-F68. Temporal analysis of gene induction revealed reversals of stress-induced altered expression of growth factors, proinflammatory cytokines, and chemokines essential for favorable wound healing, at various time points. KSLW-treatment in RST mice demonstrated faster wound closure throughout the stress period. KSLW, at micromolar concentrations, demonstrated a significant effect on neutrophil

  1. Evaluation of cytotoxicity, antimicrobial activity and physicochemical properties of a calcium aluminate-based endodontic material

    Directory of Open Access Journals (Sweden)

    Emmanuel Joao Nogueira Leal SILVA

    2014-01-01

    Full Text Available A calcium aluminate-based endodontic material, EndoBinder, has been developed in order to reduce MTA negative characteristics, preserving its biological properties and clinical applications. Objectives: The aim of this study was to evaluate the cytotoxicity, antimicrobial activity, pH, solubility and water sorption of EndoBinder and to compare them with those of white MTA (WMTA. Material and Methods: Cytotoxicity was assessed through a multiparametric analysis employing 3T3 cells. Antimicrobial activity against Enterococcus faecalis (ATCC 29212, Staphylococcus aureus. (ATCC 25923 and Candida albicans (ATCC 10556 was determined by the agar diffusion method. pH was measured at periods of 3, 24, 72 and 168 hours. Solubility and water sorption evaluation were performed following ISO requirements. Data were statistically analyzed by ANOVA and Tukey`s test with a significance level of 5%. Results: EndoBinder and WMTA were non-cytotoxic in all tested periods and with the different cell viability parameters. There was no statistical differences between both materials (P>.05. All tested materials were inhibitory by direct contact against all microbial strains tested. EndoBinder and WMTA presented alkaline pH in all tested times with higher values of pH for WMTA (P.05. Conclusion: Under these experimental conditions, we concluded that the calcium aluminate-based endodontic material EndoBinder demonstrated suitable biological and physicochemical properties, so it can be suggested as a material of choice in root resorption, perforations and root-end filling.

  2. Composition, Cytotoxic and Antimicrobial Activities of Satureja intermedia C.A.Mey Essential Oil

    Directory of Open Access Journals (Sweden)

    Javad Sharifi-Rad

    2015-08-01

    Full Text Available In this study, the essential oil (EO constituents from the aerial parts of Satureja intermedia C.A.Mey were detected by GC and GC/MS. The antimicrobial activity of EO on oral pathogens and its cytotoxicity to human cancer cells were determined by the microbroth dilution method and the crystal violet staining method, respectively. Thirty-nine compounds were identified and the main EO constituents were γ-terpinene (37.1%, thymol (30.2%, p-cymene (16.2%, limonene (3.9%, α-terpinene (3.3%, myrcene (2.5%, germacrene B (1.4%, elemicine (1.1% and carvacrol (0.5%. The S. intermedia EO showed a concentration-dependent decrease in viability of Hep-G2 (hepatocellular carcinoma and MCF-7 (breast adenocarcinoma human cancer cell lines (p < 0.05. Antimicrobial screening of S. intermedia EO demonstrated slight antibacterial and antifungal activities against Streptococcus mutants, S. salivarius, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. glabrata. Further preclinical studies are needed to assess the efficacy and safety of S. intermedia EO as a new promising anticancer agent.

  3. Green synthesis of silver nanoparticles by Bacillus methylotrophicus, and their antimicrobial activity.

    Science.gov (United States)

    Wang, Chao; Kim, Yeon Ju; Singh, Priyanka; Mathiyalagan, Ramya; Jin, Yan; Yang, Deok Chun

    2016-06-01

    The synthesis of silver nanoparticles (AgNPs) by microorganisms is an area attracting growing interest in nanobiotechnology, due to the applications of these nanoparticles in various products including cosmetics and biosensors, and in the biomedical, clinical, and bioimaging fields as well. Various microorganisms have been found to be able to synthesize AgNPs when silver salts are supplied in the reaction system. The main objectives of this study were to evaluate the efficiency of synthesis of AgNPs by the strain Bacillus methylotrophicus DC3, isolated from the soil of Korean ginseng, a traditionally known oriental medicinal plant in Korea. The AgNPs showed maximum absorbance at 416 nm, when assayed by ultraviolet-visible spectroscopy (UV-vis). The field emission transmission electron micrograph (FE-TEM) results showed that the particles were spherical and 10-30 nm in size. In addition, the product was also characterized by energy dispersive X-ray spectroscopy (EDX), which displayed a 3 keV peak corresponding to the silver nanocrystal. Elemental mapping results also confirmed the presence of silver elements in the electron micrograph region. Furthermore, the AgNPs demonstrated antimicrobial activity against various pathogenic microorganisms such as Candida albicans, Salmonella enterica, Escherichia coli, and Vibrio parahaemolyticus, with enhanced antimicrobial activity being exhibited against C. albicans. Therefore, the current study describes the simple, efficient, and green method of synthesis of AgNPs by B. methylotrophicus DC3.

  4. Antimicrobial activity of pleurocidin is retained in Plc-2, a C-terminal 12-amino acid fragment.

    Science.gov (United States)

    Souza, Andre L A; Díaz-Dellavalle, Paola; Cabrera, Andrea; Larrañaga, Patricia; Dalla-Rizza, Marco; De-Simone, Salvatore G

    2013-07-01

    An analysis of a series of five peptides composed of various portions of the pleurocidin (Plc) sequence identified a l2-amino acid fragment from the C-terminus of Plc, designated Plc-2, as the smallest fragment that retained a antimicrobial activity comparable to that of the parent compound. MIC tests in vitro with low-ionic-strength medium showed that Plc-2 has potent activity against Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus but not against Enterococcus faecalis. The antifungal activity of the synthetic peptides against phytopathogenic fungi, such as Fusarium oxysporum, Colletotrichum sp., Aspergillus niger and Alternaria sp., also identified Plc-2 as a biologically active peptide. Microscopy studies of fluorescently stained fungi treated with Plc-2 demonstrated that cytoplasmic and nuclear membranes were compromised in all strains of phytopathogenic fungi tested. Together, these results identify Plc-2 as a potential antimicrobial agent with similar properties to its parent compound, pleurocidin. In addition, it demonstrated that the KHVGKAALTHYL residues are critical for the antimicrobial activity described for pleurocidin.

  5. Antimicrobial activity of spices like cloves Cardamom and Cinnamon on Bacillus and Pseudomonas

    OpenAIRE

    Taneesha Chawla; Nida Itrat Abbasi; Aishwarya Tandon; Suneetha V

    2014-01-01

    Spices have been used in our country cuisines since times immemorial. Their use was mainly due to health benefits as herbs and for the aroma they provided in the food. However, little did we know at that time that these spices also have antimicrobial activity. Today, they stand as giants in ayurvedic medicine with substances like turmeric, cloves and cardamom being used in every house-hold. This paper pertains to the antimicrobial activity of three such spices Cloves, Cinnamon and Cardamom on...

  6. A new class of multi-substituted oxazole derivatives: Synthesis and antimicrobial activity

    Indian Academy of Sciences (India)

    A Babul Reddy; R V Hymavathi; G Narayana Swamy

    2013-05-01

    A new and efficient method for the synthesis of multi-substituted oxazole derivatives from various aldehydes has been described. Twenty novel multi-substituted oxazoles containing a heterocyclic moiety were synthesized and evaluated for their antimicrobial activity. The prepared compounds are all reported for the first time and their structures were established by elemental analysis, IR, 1H-NMR, and 13C-NMR and Mass spectra. All the synthesized compounds exhibited in vitro antimicrobial activity.

  7. Antimicrobial activity of histidine-rich peptides is dependent on acidic conditions.

    OpenAIRE

    Kacprzyk, Lukasz; Rydengård, Victoria; Mörgelin, Matthias; Davoudi, Mina; Pasupuleti, Mukesh; Malmsten, Martin; Schmidtchen, Artur

    2007-01-01

    Synthetic peptides composed of multiples of the consensus heparin-binding Cardin and Weintraub sequences AKKARA and ARKKAAKA are antimicrobial. Replacement of lysine and arginine by histidine in these peptides completely abrogates their antimicrobial and heparin-binding activities at neutral pH. However, the antibacterial activity against Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) as well as the fungus Cand...

  8. Antimicrobial Activity and Elemental Composition of Sarcocephalus latifolius Fruits: An Ethnopharmacological Based Evaluation

    OpenAIRE

    Alsiddig Osama; Sufyan Awadelkarim; Mai Omer; Saga Yasser; Yousra Basher; Thoyba Elmabrouk; Afnan Abdalmaged

    2017-01-01

    Sarcocephalus latifolius have been part of Sudanese ethnomedicine since long time. The current study was conducted to evaluate the antimicrobial activity of Sarcocephalus latifolius fruits and to investigate its elemental composition. The antimicrobial activities of the ethanolic crude extract and solvents fractions (hexane chloroform, acetone and aqua’s) were investigated by the disk diffusion method. These fractions were further screened for the presence of eight secondary metabolites using...

  9. Electrochemical and antimicrobial activity of tellurium oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Pramod K. [Department of Applied Sciences and Humanities, Jamia Millia Islamia, New Delhi 110067 (India); Special Centre for Nanosciences, Jawaharlal Nehru University, New Delhi 110067 (India); Sharma, Prem Prakash; Sharma, Anshu [Special Centre for Nanosciences, Jawaharlal Nehru University, New Delhi 110067 (India); Khan, Zishan H., E-mail: zishan_hk@yahoo.co.in [Department of Applied Sciences and Humanities, Jamia Millia Islamia, New Delhi 110067 (India); Solanki, Pratima R., E-mail: pratimarsolanki@gmail.com [Special Centre for Nanosciences, Jawaharlal Nehru University, New Delhi 110067 (India)

    2016-09-15

    Highlights: • TeO{sub 2} NPs synthesized without using any catalyst by chemical vapour deposition method. • The growth temperature was 410 °C with continuous flow of O{sub 2.} • TeO{sub 2} NPs have anti-bacterial activity against E. coli, K. pneumoniae and S. aureus while enhances the growth of S. pyogenes. • TeO{sub 2} shows maximum redox current at pH 7 for phosphate buffer solution. - Abstract: Thin film of tellurium oxide (TeO{sub 2}) has been synthesized by chemical vapour deposition method onto indium tin oxide (ITO) coated glass substrate without using any catalyst. XRD pattern of TeO{sub 2} thin film suggests that the structure of TeO{sub 2} changes from amorphous to crystalline (paratellurite) on dispersing into deionized water. Zeta potential measurement reveals a positive surface potential of 28.8 mV. TEM images shows spherical shaped TeO{sub 2} nanoparticles having average particle size of 65 nm. Electrochemical studies of TeO{sub 2}/ITO electrode exhibit improved electron transfer owing to its inherent electron transfer property at pH 7.0 of phosphate buffer. Antimicrobial activity of TeO{sub 2} has been studied for gram-positive (Staphylococcus aureus and Streptococcus pyogenes) and gram negative (Escherichia coli and Klebsiella pneumoniae) bacterial and fungal strains (Aspergillus nizer and Candida albicans). These studies suggest that the TeO{sub 2} NPs inhibit the growth of E. coli, K. pneumoniae and S. aureus bacteria, whereas the same particles enhance the growth of S. pyogenes bacteria.

  10. Studies on antimicrobial activities of solvent extracts of different spices.

    Science.gov (United States)

    Keskin, Dilek; Toroglu, Sevil

    2011-03-01

    The antimicrobial activities of the ethyl acetate, acetone and methanol extract of 12 plant species were studied. The extract of Capsicum annuum (red pepper) (fruit) Zingiber officinale (ginger) (root), Cuminum cyminum (cumin), Alpinia ficinarum (galingale), Coriandrum sativum (coriander), Cinnamomun zeylanicum Nees (cinnamomun), Origanum onites L. (thyme), Folium sennae (senna), Eugenia caryophyllata (cloves), Flos tiliae (lime), Folium menthae crispae (peppermint) and Piper nigrum (blackpepper) were tested in vitro against 2 fungi and 8 bacterial species by the disc diffusion method. Klebsiella pneumonia 13883, Bacillus megaterium NRS, Pseudomonas aeroginosa ATCC 27859, Staphylococcus aureus 6538 P, Escherichia coil ATCC 8739, Enterobacter cloaca ATCC 13047, Corynebacterium xerosis UC 9165, Streptococcus faecalis DC 74, Kluyveromyces marxianus, Rhodotorula rubra were used in this investigation. The results indicated that extracts of different spices has shown antibacterial activity in the range of 7-24 mm 30 microl(-1) inhibition zone Eugenia caryophyllata (clove), 7-20 mm 30microl(-1) inhibition zone Capsicum annum (red pepper) and Cinnamomun zeylanicum (cinnamon) bark, 7-18 mm 30microl(-1) inhibition zone Folium sennae (senna) leaves, 7-16 mm 30 microl(-1) inhibition zone Zingiber officinale (ginger) root, 7-15 mm 30microl(-1) inhibition zone Cuminum cyminum (cumin) seed, 7-14 mm 30 microl(-1) inhibition zone Folium menthae crispae (peppermint), Origanum onites (thyme) leaves and Alpinia ficinarum (galingale) root, 7-12 mm 30 microl(-1) inhibiton zone Piper nigrum (blackpepper), 7-11 mm 30microl(-1) inhibition zone Flos tiliae (lime) leaves, 7-8 mm 30microl(-1) inhibition zone Coriandrum sativum (coriander) to the microorganisms tested.

  11. Chemical features of Ganoderma polysaccharides with antioxidant, antitumor and antimicrobial activities.

    Science.gov (United States)

    Ferreira, Isabel C F R; Heleno, Sandrina A; Reis, Filipa S; Stojkovic, Dejan; Queiroz, Maria João R P; Vasconcelos, M Helena; Sokovic, Marina

    2015-06-01

    Ganoderma genus comprises one of the most commonly studied species worldwide, Ganoderma lucidum. However, other Ganoderma species have been also reported as important sources of bioactive compounds. Polysaccharides are important contributors to the medicinal properties reported for Ganoderma species, as demonstrated by the numerous publications, including reviews, on this matter. Yet, what are the chemical features of Ganoderma polysaccharides that have bioactivity? In the present manuscript, the chemical features of Ganoderma polysaccharides with reported antioxidant, antitumor and antimicrobial activities (the most studied worldwide) are analyzed in detail. The composition of sugars (homo- versus hetero-glucans and other polysaccharides), type of glycosidic linkages, branching patterns, and linkage to proteins are discussed. Methods for extraction, isolation and identification are evaluated and, finally, the bioactivity of polysaccharidic extracts and purified compounds are discussed. The integration of data allows deduction of structure-activity relationships and gives clues to the chemical aspects involved in Ganoderma bioactivity.

  12. Antimicrobial activity of electrospun poly(butylenes succinate) fiber mats containing PVP-capped silver nanoparticles.

    Science.gov (United States)

    Tian, Ligang; Wang, Pingli; Zhao, Zhiguo; Ji, Junhui

    2013-12-01

    In this study, biodegradable poly(butylenes succinate) (PBS) fiber mats containing silver nanoparticles (AgNPs) were prepared by the electrospinning process. Small AgNPs (fiber mats and the distribution of the AgNPs were well characterized by TEM and SEM. The release of Ag from the PBS fiber mats was quantitively determined by ICP. The PBS fiber mats with 0.29 % AgNPs content showed strong antimicrobial activity against both gram-positive Staphylococcus aureus and gram-negative Escherichia coli with the efficacy as high as 99 %. The effective bactericidal activity on E. coli was demonstrated for a short contacting time with the PBS-AgNPs fiber mats. In addition, the long-term release performance of Ag from the fiber mats can keep inhibiting the bacterial growth in the mats over a long period of time.

  13. AKTIVITAS ANTIMIKROBIAL PADA SUSU KUDA SUMBAWA [Antimicrobial Activity of the Sumbawa Mare Milk

    Directory of Open Access Journals (Sweden)

    Hermawati D1

    2004-04-01

    Full Text Available The research objectives where to verify the antimicrobial activity of mare milk from Sumbawa island and to further study the characteristics of the antimicrobial compound. The experiments were conducted involving 115 milk samples of Sumbawa mare and three different groups of control milk i.e. from 20 milk samples of working/ cart mares from Java, 2 samples of racing mares from Tangerang horse farm and 15 samples of dairy cows from Bogor.The results concluded that all milk samples of Sumbawa mares contained strong antimicrobial activity as tested to 9 species of bacteria. All control samples did not show antimicrobial activity, except milk samples from racing mares which showed low antibacterial activity. The racing mares were then indentified as crossbred between male Thoroughbred and female Sumbawa horse. This finding supports and suggests that the native Sumbawa horses have genetic potential to the antimicrobial activity in their milk produced. Polarity tests using 5 organic solvents of different polarity indicated that the antimicrobial activity compound was very polar but had lower polarity than water. The bioactive coumpound did not dissolve in non polar hexane but strongly dissolved in the polar methanol solvent.

  14. Synthesis, antimicrobial activity and advances in structure-activity relationships (SARs) of novel tri-substituted thiazole derivatives.

    Science.gov (United States)

    Reddy, Guda Mallikarjuna; Garcia, Jarem Raul; Reddy, Vemulapati Hanuman; de Andrade, Ageo Meier; Camilo, Alexandre; Pontes Ribeiro, Renan Augusto; de Lazaro, Sergio Ricardo

    2016-11-10

    Trisubstituted thiazoles were synthesized and studied for their antimicrobial activity and supported by theoretical calculations. In addition, MIC, MBC and MFC were also tested. Moreover, the present study was analyzed to scrutinize comprehensive structure-activity relationships. In fact, LUMO orbital energy and orbital orientation was reliable to explain their antibacterial and antifungal assay. Amongst the tested compounds, tri-methyl-substituted thiazole compound showed higher antimicrobial activity and low MIC value due to highest LUMO energy.

  15. Synthesis, Antimicrobial, and Anti-HIV1 Activity of Quinazoline-4(3H-one Derivatives

    Directory of Open Access Journals (Sweden)

    K. Vijayakumar

    2013-01-01

    Full Text Available The present investigation aims to synthesize 11 compounds of quinazoline-1 derivatives and to test their antimicrobial and anti-HIV1 activities. A quick-witted method was developed for the synthesis of novel substituted quinazolinone derivatives by summarizing diverse diamines with benzoxazine reactions, and it demonstrated the benefits of typical reactions, handy operation, and outstanding product yields. These compounds were confirmed by elemental analysis, I R, 1H NMR, 13C NMR, and mass spectra. Then antimicrobial and anti-HIV1 activities of the compounds were tested in-vitro. It was found that compounds 7–11 possessed a wide range of anti microbial and anti-HIV1 activity.

  16. Antimicrobial Activity of Peptides Derived from Olive Flounder Lipopolysaccharide Binding Protein/Bactericidal Permeability-Increasing Protein (LBP/BPI

    Directory of Open Access Journals (Sweden)

    Bo-Hye Nam

    2014-10-01

    Full Text Available We describe the antimicrobial function of peptides derived from the C-terminus of the olive flounder LBP BPI precursor protein. The investigated peptides, namely, ofLBP1N, ofLBP2A, ofLBP4N, ofLBP5A, and ofLBP6A, formed α-helical structures, showing significant antimicrobial activity against several Gram-negative bacteria, Gram-positive bacteria, and the yeast Candida albicans, but very limited hemolytic activities. The biological activities of these five analogs were evaluated against biomembranes or artificial membranes for the development of candidate therapeutic agents. Gel retardation studies revealed that peptides bound to DNA and inhibited migration on an agarose gel. In addition, we demonstrated that ofLBP6A inhibited polymerase chain reaction. These results suggested that the ofLBP-derived peptide bactericidal mechanism may be related to the interaction with intracellular components such as DNA or polymerase.

  17. Antimicrobial activity of peptides derived from olive flounder lipopolysaccharide binding protein/bactericidal permeability-increasing protein (LBP/BPI).

    Science.gov (United States)

    Nam, Bo-Hye; Moon, Ji-Young; Park, Eun-Hee; Kim, Young-Ok; Kim, Dong-Gyun; Kong, Hee Jeong; Kim, Woo-Jin; Jee, Young Ju; An, Cheul Min; Park, Nam Gyu; Seo, Jung-Kil

    2014-10-17

    We describe the antimicrobial function of peptides derived from the C-terminus of the olive flounder LBP BPI precursor protein. The investigated peptides, namely, ofLBP1N, ofLBP2A, ofLBP4N, ofLBP5A, and ofLBP6A, formed α-helical structures, showing significant antimicrobial activity against several Gram-negative bacteria, Gram-positive bacteria, and the yeast Candida albicans, but very limited hemolytic activities. The biological activities of these five analogs were evaluated against biomembranes or artificial membranes for the development of candidate therapeutic agents. Gel retardation studies revealed that peptides bound to DNA and inhibited migration on an agarose gel. In addition, we demonstrated that ofLBP6A inhibited polymerase chain reaction. These results suggested that the ofLBP-derived peptide bactericidal mechanism may be related to the interaction with intracellular components such as DNA or polymerase.

  18. Antimicrobial activity of cream incorporated with silver nanoparticles biosynthesized from Withania somnifera.

    Science.gov (United States)

    Marslin, Gregory; Selvakesavan, Rajendran K; Franklin, Gregory; Sarmento, Bruno; Dias, Alberto C P

    2015-01-01

    We report on the antimicrobial activity of a cream formulation of silver nanoparticles (AgNPs), biosynthesized using Withania somnifera extract. Aqueous extracts of leaves promoted efficient green synthesis of AgNPs compared to fruits and root extracts of W. somnifera. Biosynthesized AgNPs were characterized for their size and shape by physical-chemical techniques such as UV-visible spectroscopy, laser Doppler anemometry, transmission electron microscopy, scanning electron microscopy, atomic force microscopy, X-ray diffraction, and X-ray energy dispersive spectroscopy. After confirming the antimicrobial potential of AgNPs, they were incorporated into a cream. Cream formulations of AgNPs and AgNO3 were prepared and compared for their antimicrobial activity against human pathogens (Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris, Escherichia coli, and Candida albicans) and a plant pathogen (Agrobacterium tumefaciens). Our results show that AgNP creams possess significantly higher antimicrobial activity against the tested organisms.

  19. Antimicrobial Activity and Mechanism of Inhibition of Silver Nanoparticles against Extreme Halophilic Archaea.

    Science.gov (United States)

    Thombre, Rebecca S; Shinde, Vinaya; Thaiparambil, Elvina; Zende, Samruddhi; Mehta, Sourabh

    2016-01-01

    Haloarchaea are salt-loving halophilic microorganisms that inhabit marine environments, sea water, salterns, and lakes. The resistance of haloarchaea to physical extremities that challenge organismic survival is ubiquitous. Metal and antibiotic resistance of haloarchaea has been on an upsurge due to the exposure of these organisms to metal sinks and drug resistance genes augmented in their natural habitats due to anthropogenic activities and environmental pollution. The efficacy of silver nanoparticles (SNPs) as a potent and broad spectrum inhibitory agent is known, however, there are no reports on the inhibitory activity of SNPs against haloarchaea. In the present study, we have investigated the antimicrobial potentials of SNPs synthesized using aqueous leaf extract of Cinnamomum tamala against antibiotic resistant haloarchaeal isolates Haloferax prahovense RR8, Haloferax lucentense RR15, Haloarcula argentinensis RR10 and Haloarcula tradensis RR13. The synthesized SNPs were characterized by UV-Vis spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, X-ray diffraction and Fourier transform infrared spectroscopy. The SNPs demonstrated potent antimicrobial activity against the haloarchaea with a minimum inhibitory concentration of 300-400 μg/ml. Growth kinetics of haloarchaea in the presence of SNPs was studied by employing the Baranyi mathematical model for microbial growth using the DMFit curve fitting program. The C. tamala SNPs also demonstrated cytotoxic activity against human lung adenocarcinoma epithelial cell line (A540) and human breast adenocarcinoma cell line (MCF-7). The mechanism of inhibition of haloarchaea by the SNPs was investigated. The plausible mechanism proposed is the alterations and disruption of haloarchaeal membrane permeability by turbulence, inhibition of respiratory dehydrogenases and lipid peroxidation causing cellular and DNA damage resulting in cell death.

  20. Antimicrobial Activity and Mechanism of Inhibition of Silver Nanoparticles against Extreme Halophilic Archaea

    Science.gov (United States)

    Thombre, Rebecca S.; Shinde, Vinaya; Thaiparambil, Elvina; Zende, Samruddhi; Mehta, Sourabh

    2016-01-01

    Haloarchaea are salt-loving halophilic microorganisms that inhabit marine environments, sea water, salterns, and lakes. The resistance of haloarchaea to physical extremities that challenge organismic survival is ubiquitous. Metal and antibiotic resistance of haloarchaea has been on an upsurge due to the exposure of these organisms to metal sinks and drug resistance genes augmented in their natural habitats due to anthropogenic activities and environmental pollution. The efficacy of silver nanoparticles (SNPs) as a potent and broad spectrum inhibitory agent is known, however, there are no reports on the inhibitory activity of SNPs against haloarchaea. In the present study, we have investigated the antimicrobial potentials of SNPs synthesized using aqueous leaf extract of Cinnamomum tamala against antibiotic resistant haloarchaeal isolates Haloferax prahovense RR8, Haloferax lucentense RR15, Haloarcula argentinensis RR10 and Haloarcula tradensis RR13. The synthesized SNPs were characterized by UV-Vis spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, X-ray diffraction and Fourier transform infrared spectroscopy. The SNPs demonstrated potent antimicrobial activity against the haloarchaea with a minimum inhibitory concentration of 300–400 μg/ml. Growth kinetics of haloarchaea in the presence of SNPs was studied by employing the Baranyi mathematical model for microbial growth using the DMFit curve fitting program. The C. tamala SNPs also demonstrated cytotoxic activity against human lung adenocarcinoma epithelial cell line (A540) and human breast adenocarcinoma cell line (MCF-7). The mechanism of inhibition of haloarchaea by the SNPs was investigated. The plausible mechanism proposed is the alterations and disruption of haloarchaeal membrane permeability by turbulence, inhibition of respiratory dehydrogenases and lipid peroxidation causing cellular and DNA damage resulting in cell death. PMID:27679615

  1. Antimicrobial Activity and Mechanism of inhibition of Silver Nanoparticles against Extreme Halophilic Archaea

    Directory of Open Access Journals (Sweden)

    Rebecca Thombre

    2016-09-01

    Full Text Available Haloarchaea are salt-loving halophilic microorganism’s that inhabit marine environments, sea water, salterns, and lakes. The resistance of haloarchaea to physical extremities that challenge organismic survival is ubiquitous. Metal and antibiotic resistance of haloarchaea has been on an upsurge due to the exposure of these organisms to metal sinks and drug resistance genes augmented in their natural habitats due to anthropogenic activities and environmental pollution. The efficacy of silver nanoparticles (SNPs as a potent and broad spectrum inhibitory agent is known however, there are no reports on the inhibitory activity of SNPs against haloarchaea. In the present study, we have investigated the antimicrobial potentials of SNPs synthesized using aqueous leaf extract of Cinnamomum tamala against antibiotic resistant haloarchaeal isolates Haloferax prahovense RR8, Haloferax lucentense RR15, Haloarcula argentinensis RR10 and Haloarcula tradensis RR13. The synthesized SNPs were characterized by UV-Vis spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, X-ray diffraction and Fourier transform infrared spectroscopy. The SNPs demonstrated potent antimicrobial activity against the haloarchaea with a minimum inhibitory concentration of 300- 400µg/ml. Growth kinetics of haloarchaea in the presence of SNPs was studied by employing the Baranyi mathematical model for microbial growth using the DMFit curve fitting programme. The C. tamala SNPs also demonstrated cytotoxic activity against human lung adenocarcinoma epithelial cell line (A540 and human breast adenocarcinoma cell line (MCF-7. The mechanism of inhibition of haloarchaea by the SNPs was investigated. The plausible mechanism proposed is the alterations and disruption of haloarchaeal membrane permeability by turbulence, inhibition of respiratory dehydrogenases and lipid peroxidation causing cellular and DNA damage resulting in cell death.

  2. Magnetically Recoverable and Reusable Antimicrobial Nanocomposite Based on Activated Carbon, Magnetite Nanoparticles, and Silver Nanoparticles for Water Disinfection

    Directory of Open Access Journals (Sweden)

    Ping Y. Furlan

    2017-06-01

    Full Text Available Recent advancements in nanotechnology have led to the development of innovative, low-cost and highly efficient water disinfection technologies that may replace or enhance the conventional methods. In this study, we introduce a novel procedure for preparing a bifunctional activated carbon nanocomposite in which nanoscale-sized magnetic magnetite and antimicrobial silver nanoparticles are incorporated (MACAg. The antimicrobial efficacy of the nanocomposite was tested against Escherichia coli (E. coli. MACAg (0.5 g, 0.04% Ag was found to remove and kill 106–107 CFU (colony-forming units in 30 min via a shaking test and the removing and killing rate of the nanocomposites increased with increasing silver content and decreased with increasing CFU. The inhibition zone tests revealed, among the relevant components, only Ag nanoparticles and Ag+ ions showed antimicrobial activities. The MACAg was easily recoverable from treated water due to its magnetic properties and was able to remove and kill 106 CFU after multiple-repeated use. The MACAg nanocomposite also demonstrated its feasibility and applicability for treating a surface water containing 105 CFU. Combining low cost due to easy synthesis, recoverability, and reusability with high antimicrobial efficiency, MACAg may provide a promising water disinfection technology that will find wide applications.

  3. Characteristics and antimicrobial activity of copper-based materials

    Science.gov (United States)

    Li, Bowen

    In this study, copper vermiculite was synthesized, and the characteristics, antimicrobial effects, and chemical stability of copper vermiculite were investigated. Two types of copper vermiculite materials, micron-sized copper vermiculite (MCV) and exfoliated copper vermiculite (MECV), are selected for this research. Since most of the functional fillers used in industry products, such as plastics, paints, rubbers, papers, and textiles prefer micron-scaled particles, micron-sized copper vermiculite was prepared by jet-milling vermiculite. Meanwhile, since the exfoliated vermiculite has very unique properties, such as high porosity, specific surface area, high aspect ratio of laminates, and low density, and has been extensively utilized as a functional additives, exfoliated copper vermiculite also was synthesized and investigated. The antibacterial efficiency of copper vermiculite was qualitatively evaluated by the diffusion methods (both liquid diffusion and solid diffusion) against the most common pathogenic species: Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Klebsiella pneumoniae (K. pneumoniae). The result showed that the release velocity of copper from copper vermiculite is very slow. However, copper vermiculite clearly has excellent antibacterial efficiency to S. aureus, K. pneumoniae and E. coli. The strongest antibacterial ability of copper vermiculite is its action on S. aureus. The antibacterial efficiency of copper vermiculite was also quantitatively evaluated by determining the reduction rate (death rate) of E. coli versus various levels of copper vermiculite. 10 ppm of copper vermiculite in solution is sufficient to reduce the cell population of E. coli, while the untreated vermiculite had no antibacterial activity. The slow release of copper revealed that the antimicrobial effect of copper vermiculite was due to the strong interactions between copper ions and bacteria cells. Exfoliated copper vermiculite has even stronger

  4. Antimicrobial Activity of an Alcaligenes faecalis Strain Isolated from Oil Contaminated Soil

    Directory of Open Access Journals (Sweden)

    Yaghoobi Avini, M. (MSc

    2015-01-01

    Full Text Available Background and Objective: The bacteria living in the specific ecological conditions are among the most promising antimicrobial producers. This study aimed at isolating antimicrobial producing bacteria from soils contaminated with crude oil. Material and Methods: the samples were obtained from crude oil contaminated soils around Dezful located in Khuzestan province, Iran, and antimicrobial producing bacteria were isolated using disc diffusion and cross streak culture. Then, the best bacterium was selected and its antimicrobial potency was studied against indicator microorganisms. The isolate was also characterized based on biochemical properties and phylogenetic analysis. Results: based on the results, the highest antimicrobial activity of isolated bacterium was related to Candida albicans, Aspergillus niger, Bacillus subtilis, E. coli and Klebsiella pneumonia. An intermediate effect was determined against Serratia marcesens and Staphylococcus aureus, whereas no effect was observed against three strains of Enterococcus. Using biochemical characteristics and phenotypic traits, the isolate was identified as Alcaligenes faecalis. Conclusion: given that the isolate has broad spectrum activity against a various range of microorganisms and in comparison with some antimicrobial compounds produced by other Alcaligenes species, it seems the novelty of this antimicrobial compound.

  5. ß-defensin-2 in breast milk displays a broad antimicrobial activity against pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Joanna Baricelli

    2015-02-01

    Full Text Available OBJECTIVE: To describe the antimicrobial activity of ß-defensin-2 produced in the mammary gland and secreted in human breast milk. METHODS: The peptide production was performed by DNA cloning. ß-defensin-2 levels were quantified in 61 colostrum samples and 39 mature milk samples from healthy donors, by an indirect enzyme-linked immunosorbent assay (ELISA. Using halo inhibition assay, this study assessed activity against seven clinical isolates from diarrheal feces of children between 0 and 2 years of age. The activity of ß-defensin-2 against three opportunistic pathogens that can cause nosocomial infections was determined by microdilution test. RESULTS: The peptide levels were higher in colostrum (n = 61 than in mature milk samples (n = 39, as follows: median and range, 8.52 (2.6-16.3 µg/ml versus 0.97 (0.22-3.78, p < 0.0001; Mann-Whitney test. The recombinant peptide obtained showed high antimicrobial activity against a broad range of pathogenic bacteria. Its antibacterial activity was demonstrated in a disk containing between 1-4 µg, which produced inhibition zones ranging from 18 to 30 mm against three isolates of Salmonella spp. and four of E. coli. ß-defensin-2 showed minimum inhibitory concentrations (MICs of 0.25 µg/mL and 0.5 µg/mL for S. marcescen and P. aeruginosa, respectively, while a higher MIC (4 µg/mL was obtained against an isolated of multidrug-resistant strain of A. baumannii. CONCLUSIONS: To the authors' knowledge, this study is the first to report ß-defensin-2 levels in Latin American women. The production and the activity of ß-defensin-2 in breast milk prove its importance as a defense molecule for intestinal health in pediatric patients.

  6. Antioxidant,antimicrobial,cytotoxic and analgesic activities of ethanolic extract of Mentha arvensis L.

    Institute of Scientific and Technical Information of China (English)

    Nripendra; Nath; Biswas; Subarna; Saha; Mohammed; khadem; Ali

    2014-01-01

    Objective:To investigate potential antioxidant,antimicrobial,cytotoxic and analgesic activities of ethanolic extract of Mentha arrensis l.,in different in vivo and in vitro experimental models.Methods:In vitro DPPH radical scavenging assay was used to evaluate the antioxidant activity of the plant extract.In vivo analgesic activity was carried out by acetic acid—induced writhing test in Swiss albino mice.All studies in mice were undertaken at the doses of 250 and 500 mg/kg body weight.Antibacterial activilv was studied by disk diffusion assay against some Gram—positive and Gram—negative bacterial strains.Brine shrimp lethality assay was used to investigate cyloloxicity effects of the plant extract.Results:The extract showed free radical scavenging activity in the DPPH assay(IC5041 μg/mL)compared to the standard antioxidant ascorbic acid(IC5019 μg/mL).The extract also produced prominent antimicrobial activity against Salmonella typhi.Salmonella paratyphi.Shigella boydii,Streptococcus pyogenes and Streptococcus aureus compared to standard drug kanamycin at the dose of 30 μg/disc.The extract exhibited lethality against the brine shrimp nauplii with the LC50,values of 40 μg/mL.and also 90%mortality(LC90) value was found to be 160 μg/mL.In analgesic test.the extract demonstrated statistically significant(P<0.01) analgesic effect in acetic acid induced writhing in white albino mice al both dose levels.Conclusions:These results suggest that the ethanolic extract of Mentha arvenns L.has potential antioxidant,antibacterial,cytotoxic and analgesic activities that support the ethnopharmacological uses of this plant.

  7. Identification and antimicrobial activity detection of lactic Acid bacteria isolated from corn stover silage.

    Science.gov (United States)

    Li, Dongxia; Ni, Kuikui; Pang, Huili; Wang, Yanping; Cai, Yimin; Jin, Qingsheng

    2015-05-01

    A total of 59 lactic acid bacteria (LAB) strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA) sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L.) plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC 43971(T), Micrococcus luteus ATCC 4698(T) and Escherichia coli ATCC 11775(T) were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at 100°C), but the antimicrobial activity was eliminated after treatment at 121°C for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0), but became inactive under neutral and alkaline condition (pH 7.0 to 9.0). In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory.

  8. Identification and Antimicrobial Activity Detection of Lactic Acid Bacteria Isolated from Corn Stover Silage

    Directory of Open Access Journals (Sweden)

    Dongxia Li

    2015-05-01

    Full Text Available A total of 59 lactic acid bacteria (LAB strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L. plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC 43971T, Micrococcus luteus ATCC 4698T and Escherichia coli ATCC 11775T were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at 100°C, but the antimicrobial activity was eliminated after treatment at 121°C for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0, but became inactive under neutral and alkaline condition (pH 7.0 to 9.0. In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory.

  9. Antimicrobial activity of biogenic silver nanoparticles, and silver chloride nanoparticles: an overview and comments.

    Science.gov (United States)

    Durán, Nelson; Nakazato, Gerson; Seabra, Amedea B

    2016-08-01

    The antimicrobial impact of biogenic-synthesized silver-based nanoparticles has been the focus of increasing interest. As the antimicrobial activity of nanoparticles is highly dependent on their size and surface, the complete and adequate characterization of the nanoparticle is important. This review discusses the characterization and antimicrobial activity of biogenic synthesized silver nanoparticles and silver chloride nanoparticles. By revising the literature, there is confusion in the characterization of these two silver-based nanoparticles, which consequently affects the conclusion regarding to their antimicrobial activities. This review critically analyzes recent publications on the synthesis of biogenic silver nanoparticles and silver chloride nanoparticles by attempting to correlate the characterization of the nanoparticles with their antimicrobial activity. It was difficult to correlate the size of biogenic nanoparticles with their antimicrobial activity, since different techniques are employed for the characterization. Biogenic synthesized silver-based nanoparticles are not completely characterized, particularly the nature of capped proteins covering the nanomaterials. Moreover, the antimicrobial activity of theses nanoparticles is assayed by using different protocols and strains, which difficult the comparison among the published papers. It is important to select some bacteria as standards, by following international foundations (Pharmaceutical Microbiology Manual) and use the minimal inhibitory concentration by broth microdilution assays from Clinical and Laboratory Standards Institute, which is the most common assay used in antibiotic ones. Therefore, we conclude that to have relevant results on antimicrobial effects of biogenic silver-based nanoparticles, it is necessary to have a complete and adequate characterization of these nanostructures, followed by standard methodology in microbiology protocols.

  10. Identification and Antimicrobial Activity Detection of Lactic Acid Bacteria Isolated from Corn Stover Silage

    Science.gov (United States)

    Li, Dongxia; Ni, Kuikui; Pang, Huili; Wang, Yanping; Cai, Yimin; Jin, Qingsheng

    2015-01-01

    A total of 59 lactic acid bacteria (LAB) strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA) sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L.) plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC 43971T, Micrococcus luteus ATCC 4698T and Escherichia coli ATCC 11775T were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at 100°C), but the antimicrobial activity was eliminated after treatment at 121°C for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0), but became inactive under neutral and alkaline condition (pH 7.0 to 9.0). In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory. PMID:25924957

  11. Antimicrobial activity of different tissues of snakehead fish Channa striatus (Bloch

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    Pravin Kumar N

    2012-05-01

    Full Text Available Objective: The aim of this study was to identify the presence of antimicrobial activity in different organs/tissues (gills, blood, skin, liver, intestine, kidney, tissue and ovary extract of snakehead fish Channa striatus. Methods: A total of 48 fractions from the organs and tissue extracts were obtained by solid-phase extraction and the fractions were assayed for antimicrobial activity. The screening of antimicrobial activity for all the fractions were tested against 8 human pathogens including Gram positive (Methicillin-resistant Staphylococcus aureus (MRSA, Staphylococcus aureus, Bacillus cereus and Gram negative bacteria (Salmonella enteritidis, Shigella flexneri, Acinetobacter baumanni, Escherichia coli, Klebsiella pneumoniae using the British Society for Antimicrobial Chemotherapy (BSAC standardized disc susceptibility test method. The activity was measured in terms of zone of inhibition in mm. Results: The results indicated that, among the 8 organs/tissues tested only blood and gills extract fractions (40 and 60 % ACN fraction showed inhibition against Escherichia coli and 60 % ACN fraction of gill extract showed inhibition against Salmonella enteritidis. Protein profile analysis by SDS-PAGE showed that antimicrobial activity of the partially purified blood and gill tissue extracts might be due to low molecular weight peptides. Conclusions: The present study showed that, gill and blood extracts of Channa striatus can be a potential source of an antimicrobial protein for specific human pathogens.

  12. Application of Artificial Intelligence to the Prediction of the Antimicrobial Activity of Essential Oils.

    Science.gov (United States)

    Daynac, Mathieu; Cortes-Cabrera, Alvaro; Prieto, Jose M

    2015-01-01

    Essential oils (EOs) are vastly used as natural antibiotics in Complementary and Alternative Medicine (CAM). Their intrinsic chemical variability and synergisms/antagonisms between its components make difficult to ensure consistent effects through different batches. Our aim is to evaluate the use of artificial neural networks (ANNs) for the prediction of their antimicrobial activity. Methods. The chemical composition and antimicrobial activity of 49 EOs, extracts, and/or fractions was extracted from NCCLS compliant works. The fast artificial neural networks (FANN) software was used and the output data reflected the antimicrobial activity of these EOs against four common pathogens: Staphylococcus aureus, Escherichia coli, Candida albicans, and Clostridium perfringens as measured by standardised disk diffusion assays. Results. ANNs were able to predict >70% of the antimicrobial activities within a 10 mm maximum error range. Similarly, ANNs were able to predict 2 or 3 different bioactivities at the same time. The accuracy of the prediction was only limited by the inherent errors of the popular antimicrobial disk susceptibility test and the nature of the pathogens. Conclusions. ANNs can be reliable, fast, and cheap tools for the prediction of the antimicrobial activity of EOs thus improving their use in CAM.

  13. Optimized dispersion of ZnO nanoparticles and antimicrobial activity against foodborne pathogens and spoilage microorganisms

    Science.gov (United States)

    Espitia, Paula Judith Perez; Soares, Nilda de Fátima Ferreira; Teófilo, Reinaldo F.; Vitor, Débora M.; Coimbra, Jane Sélia dos Reis; de Andrade, Nélio José; de Sousa, Frederico B.; Sinisterra, Rubén D.; Medeiros, Eber Antonio Alves

    2013-01-01

    Single primary nanoparticles of zinc oxide (nanoZnO) tend to form particle collectives, resulting in loss of antimicrobial activity. This work studied the effects of probe sonication conditions: power, time, and the presence of a dispersing agent (Na4P2O7), on the size of nanoZnO particles. NanoZnO dispersion was optimized by response surface methodology (RSM) and characterized by the zeta potential (ZP) technique. NanoZnO antimicrobial activity was investigated at different concentrations (1, 5, and 10 % w/w) against four foodborne pathogens and four spoilage microorganisms. The presence of the dispersing agent had a significant effect on the size of dispersed nanoZnO. Minimum size after sonication was 238 nm. An optimal dispersion condition was achieved at 200 W for 45 min of sonication in the presence of the dispersing agent. ZP analysis indicated that the ZnO nanoparticle surface charge was altered by the addition of the dispersing agent and changes in pH. At tested concentrations and optimal dispersion, nanoZnO had no antimicrobial activity against Pseudomonas aeruginosa, Lactobacillus plantarum, and Listeria monocytogenes. However, it did have antimicrobial activity against Escherichia coli, Salmonella choleraesuis, Staphylococcus aureus, Saccharomyces cerevisiae, and Aspergillus niger. Based on the exhibited antimicrobial activity of optimized nanoZnO against some foodborne pathogens and spoilage microorganisms, nanoZnO is a promising antimicrobial for food preservation with potential application for incorporation in polymers intended as food-contact surfaces.

  14. Immunomodulatory and Antimicrobial Activity of Babassu Mesocarp Improves the Survival in Lethal Sepsis

    Science.gov (United States)

    Prado, Dayanna S.; Barcellos, Priscila S.; Gonçalves, Azizedite G.

    2016-01-01

    Attalea speciosa syn Orbignya phalerata Mart. (babassu) has been used in the treatment of inflammatory and infectious diseases. Aim of the study. To investigate the antimicrobial and immunological activity of babassu mesocarp extract (EE). Material and Methods. The in vitro antimicrobial activity was evaluated by disk diffusion assay and by determination of the minimum inhibitory concentration (MIC) to Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA). The flavonoids and phenolic acids content were determined by chromatography. The in vivo assays were performed in Swiss mice submitted to sepsis by cecal ligation and puncture (CLP). The mice received EE subcutaneously (125 or 250 mg/Kg), 6 hours after the CLP. The number of lymphoid cells was quantified and the cytokines production was determined by ELISA after 12 h. Results. EE was effective as antimicrobial to E. faecalis, S. aureus, and MRSA. EE is rich in phenolic acids, a class of compounds with antimicrobial and immunological activity. An increased survival can be observed in those groups, possibly due to a significant inhibition of TNF-α and IL-6. Conclusions. The EE showed specific antimicrobial activity in vitro and an important antiseptic effect in vivo possibly due to the antimicrobial and immunomodulatory activity. PMID:27630733

  15. Immunomodulatory and Antimicrobial Activity of Babassu Mesocarp Improves the Survival in Lethal Sepsis

    Directory of Open Access Journals (Sweden)

    Elizabeth S. B. Barroqueiro

    2016-01-01

    Full Text Available Attalea speciosa syn Orbignya phalerata Mart. (babassu has been used in the treatment of inflammatory and infectious diseases. Aim of the study. To investigate the antimicrobial and immunological activity of babassu mesocarp extract (EE. Material and Methods. The in vitro antimicrobial activity was evaluated by disk diffusion assay and by determination of the minimum inhibitory concentration (MIC to Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA. The flavonoids and phenolic acids content were determined by chromatography. The in vivo assays were performed in Swiss mice submitted to sepsis by cecal ligation and puncture (CLP. The mice received EE subcutaneously (125 or 250 mg/Kg, 6 hours after the CLP. The number of lymphoid cells was quantified and the cytokines production was determined by ELISA after 12 h. Results. EE was effective as antimicrobial to E. faecalis, S. aureus, and MRSA. EE is rich in phenolic acids, a class of compounds with antimicrobial and immunological activity. An increased survival can be observed in those groups, possibly due to a significant inhibition of TNF-α and IL-6. Conclusions. The EE showed specific antimicrobial activity in vitro and an important antiseptic effect in vivo possibly due to the antimicrobial and immunomodulatory activity.

  16. Immunomodulatory and Antimicrobial Activity of Babassu Mesocarp Improves the Survival in Lethal Sepsis.

    Science.gov (United States)

    Barroqueiro, Elizabeth S B; Prado, Dayanna S; Barcellos, Priscila S; Silva, Tonicley A; Pereira, Wanderson S; Silva, Lucilene A; Maciel, Márcia C G; Barroqueiro, Rodrigo B; Nascimento, Flávia R F; Gonçalves, Azizedite G; Guerra, Rosane N M

    2016-01-01

    Attalea speciosa syn Orbignya phalerata Mart. (babassu) has been used in the treatment of inflammatory and infectious diseases. Aim of the study. To investigate the antimicrobial and immunological activity of babassu mesocarp extract (EE). Material and Methods. The in vitro antimicrobial activity was evaluated by disk diffusion assay and by determination of the minimum inhibitory concentration (MIC) to Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA). The flavonoids and phenolic acids content were determined by chromatography. The in vivo assays were performed in Swiss mice submitted to sepsis by cecal ligation and puncture (CLP). The mice received EE subcutaneously (125 or 250 mg/Kg), 6 hours after the CLP. The number of lymphoid cells was quantified and the cytokines production was determined by ELISA after 12 h. Results. EE was effective as antimicrobial to E. faecalis, S. aureus, and MRSA. EE is rich in phenolic acids, a class of compounds with antimicrobial and immunological activity. An increased survival can be observed in those groups, possibly due to a significant inhibition of TNF-α and IL-6. Conclusions. The EE showed specific antimicrobial activity in vitro and an important antiseptic effect in vivo possibly due to the antimicrobial and immunomodulatory activity.

  17. Latent Ice Recrystallization Inhibition Activity in Nonantifreeze Proteins: Ca2+-Activated Plant Lectins and Cation-Activated Antimicrobial Peptides.

    Science.gov (United States)

    Mitchell, Daniel E; Gibson, Matthew I

    2015-10-12

    Organisms living in polar regions have evolved a series of antifreeze (glyco) proteins (AFGPs) to enable them to survive by modulating the structure of ice. These proteins have huge potential for use in cellular cryopreservation, ice-resistant surfaces, frozen food, and cryosurgery, but they are limited by their relatively low availability and questions regarding their mode of action. This has triggered the search for biomimetic materials capable of reproducing this function. The identification of new structures and sequences capable of inhibiting ice growth is crucial to aid our understanding of these proteins. Here, we show that plant c-type lectins, which have similar biological function to human c-type lectins (glycan recognition) but no sequence homology to AFPs, display calcium-dependent ice recrystallization inhibition (IRI) activity. This IRI activity can be switched on/off by changing the Ca2+ concentration. To show that more (nonantifreeze) proteins may exist with the potential to display IRI, a second motif was considered, amphipathicity. All known AFPs have defined hydrophobic/hydrophilic domains, rationalizing this choice. The cheap, and widely used, antimicrobial Nisin was found to have cation-dependent IRI activity, controlled by either acid or addition of histidine-binding ions such as zinc or nickel, which promote its amphipathic structure. These results demonstrate a new approach in the identification of antifreeze protein mimetic macromolecules and may help in the development of synthetic mimics of AFPs.

  18. Crystal Structures and Antimicrobial Activity of Two Phosphorus Compounds

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    One phosphorus heterocycle compound 1, C13H13N2OPS, was synthesized by the reaction of Lawesson's reagent (LR) with o-phenylene diamine. The crystal belongs to the orthorhombic system, space group P212121 with a = 5.5274(11), b = 8.1603(16), c = 28.830(6) (A), V =1300.4(4) (A)3, Z = 4, Mr= 276.28, Dc = 1.411 g/cm3, F(000) = 576,μ = 0.360 mm-1, R = 0.0259 and wR = 0.0652 for 1414 observed reflections with I > 2σ(I). While compound 2, C14H17N2O2PS, was obtained as a ring-cleavage product of compound 1. This crystal is of monoclinic system, space group P21/c with a = 9.5619(19), b = 21.879(4), c = 7.3618(15) (A), β= 103.03(3)°, V=1500.4(5) (A)3,Z = 4, Mr= 308.33, Dc = 1.365 g/cm3, F(000) = 648, μ = 0.325 mm-1, R = 0.0383 and wR =0.0742for 2283 observed reflections with I > 2σ(I). Phosphorus atom in each compound bonds with sulfur and carbon atoms using sp3 hybrid orbitals, and crystals of these two compounds are formed and stabilized by intermolecular hydrogen bonds and Van der Waals' forces. The special structure of compound 1 leads to its good antimicrobial activity against staphylococcus aureus.

  19. Cerecidins, novel lantibiotics from Bacillus cereus with potent antimicrobial activity.

    Science.gov (United States)

    Wang, Jian; Zhang, Li; Teng, Kunling; Sun, Shutao; Sun, Zhizeng; Zhong, Jin

    2014-04-01

    Lantibiotics are ribosomally synthesized and posttranslationally modified antimicrobial peptides that are widely produced by Gram-positive bacteria, including many species of the Bacillus group. In the present study, one novel gene cluster coding lantibiotic cerecidins was unveiled in Bacillus cereus strain As 1.1846 through genomic mining and PCR screening. The designated cer locus is different from that of conventional class II lantibiotics in that it included seven tandem precursor cerA genes, one modification gene (cerM), two processing genes (cerT and cerP), one orphan regulator gene (cerR), and two immunity genes (cerF and cerE). In addition, one unprecedented quorum sensing component, comQXPA, was inserted between cerM and cerR. The expression of cerecidins was not detected in this strain of B. cereus, which might be due to repressed transcription of cerM. We constitutively coexpressed cerA genes and cerM in Escherichia coli, and purified precerecidins were proteolytically processed with the endoproteinase GluC and a truncated version of putative serine protease CerP. Thus, two natural variants of cerecidins A1 and A7 were obtained which contained two terminal nonoverlapping thioether rings rarely found in lantibiotics. Both cerecidins A1 and A7 were active against a broad spectrum of Gram-positive bacteria. Cerecidin A7, especially its mutant Dhb13A, showed remarkable efficacy against multidrug-resistant Staphylococcus aureus (MDRSA), vancomycin-resistant Enterococcus faecalis (VRE), and even Streptomyces.

  20. Antimicrobial and acetylcholinesterase inhibitory activities of Buddleja salviifolia (L.) Lam. leaf extracts and isolated compounds.

    Science.gov (United States)

    Pendota, S C; Aderogba, M A; Ndhlala, A R; Van Staden, J

    2013-07-09

    Buddleja salviifolia leaves are used for the treatment of eye infections and neurodegenerative conditions by various tribes in South Africa. This study was designed to isolate the phenolic constituents from the leaf extracts of Buddleja salviifolia and evaluate their antimicrobial and acetylcholinesterase (AChE) activities. Three phenolic compounds were isolated from the ethyl acetate fraction of a 20% aqueous methanol leaf extract of Buddleja salviifolia using Sephadex LH-20 and silica gel columns. Structure elucidation of the isolated compounds was carried out using spectroscopic techniques: mass spectrometry (ESI-TOF-MS) and NMR (1D and 2D). The extracts and isolated compounds were evaluated for antimicrobial and acetylcholinesterase activities using the microdilution technique. The bacteria used for the antimicrobial assays were Gram-positive Bacillus subtilis and Staphylococcus aureus and Gram-negative Escherichia coli and Klebsiella pneumoniae. The isolated compounds were characterized as: 4'-hydroxyphenyl ethyl vanillate (1) a new natural product, acteoside (2) and quercetin (3). The crude extract, fractions and the isolated compounds from the leaves of the plant exhibited a broad spectrum of antibacterial activity. The EtOAc fraction exhibited good activity against Bacillus subtilis and Staphylococcus aureus with MIC values ranging from 780.0 to 390.0 µg/mL. Isolated compound 2 exhibited good activity against Staphylococcus aureus with an MIC value of 62.5 µg/mL. The hexane and DCM fractions of leaves showed the best activity against Candida albicans with MIC and MFC values of 390.0 µg/mL. In the AChE inhibitory test, among the tested extracts, the hexane fraction was the most potent with an IC50 value of 107.4 µg/mL, whereas for the isolated compounds, it was compound (3) (quercetin) with an IC50 value of 66.8 µg/mL. Activities demonstrated by the extracts and isolated compounds support the ethnopharmacological use of Buddleja salviifolia against eye

  1. In vitro antimicrobial activity of propolis and Arnica montana against oral pathogens.

    Science.gov (United States)

    Koo, H; Gomes, B P; Rosalen, P L; Ambrosano, G M; Park, Y K; Cury, J A

    2000-02-01

    Arnica and propolis have been used for thousands of years in folk medicine for several purposes. They possess several biological activities such as anti-inflammatory, antifungal, antiviral and tissue regenerative, among others. Although the antibacterial activity of propolis has already been demonstrated, very few studies have been done on bacteria of clinical relevance in dentistry. Also, the antimicrobial activity of Arnica has not been extensively investigated. Therefore the aim here was to evaluate in vitro the antimicrobial activity, inhibition of adherence of mutans streptococci and inhibition of formation of water-insoluble glucan by Arnica and propolis extracts. Arnica montana (10%, w/v) and propolis (10%, w/v) extracts from Minas Gerais State were compared with controls. Fifteen microorganisms were used as follows: Candida albicans--NTCC 3736, F72; Staphylococcus aureus--ATCC 25923; Enterococcus faecalis--ATCC 29212; Streptococcus sobrinus 6715; Strep. sanguis--ATCC 10556; Strep. cricetus--HS-6; Strep. mutans--Ingbritt 1600; Strep. mutans--OMZ 175; Actinomyces naeslundii--ATCC 12104, W 1053; Act. viscosus OMZ 105; Porphyromonas gingivalis; Porph. endodontalis and Prevotella denticola (the last three were clinical isolates). Antimicrobial activity was determined by the agar diffusion method and the zones of growth inhibition were measured. To assess cell adherence to a glass surface, the organisms were grown for 18 h at 37 degrees C in test-tubes at a 30 degree angle. To assay water-insoluble glucan formation, a mixture of crude glucosyltransferase and 0.125 M sucrose was incubated for 18 h at 37 degrees C in test-tubes at a 30 degree angle. Arnica and propolis extracts (20 microl) were added to these tubes to evaluate the % of inhibition of cell adherence and water-insoluble glucan formation. The propolis extract significantly inhibited all the microorganisms tested (p propolis extract at a final concentration of 400 microg/ml and 500 microg

  2. Phytochemical investigation and antimicrobial activity of Derris scandens

    Directory of Open Access Journals (Sweden)

    Hidayat Hussain

    2015-10-01

    Full Text Available Different fractions of root and stem of Derris scandens demonstrated good antibacterial (Escherichia coli, and Bacillus megaterium, antialgal (Chlorella fusca, and antifungal (Microbotryum violaceum activities. Phytochemical investiga