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Sample records for high antibacterial activity

  1. Highly antioxidant carotene-lipid nanocarriers: synthesis and antibacterial activity

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    Lacatusu, Ioana; Badea, Nicoleta, E-mail: nicoleta.badea@gmail.com; Ovidiu, Oprea [University POLITEHNICA of Bucharest, Faculty of Applied Chemistry and Materials Science (Romania); Bojin, Dionezie [Faculty of Engineering and Materials Science (Romania); Meghea, Aurelia [University POLITEHNICA of Bucharest, Faculty of Applied Chemistry and Materials Science (Romania)

    2012-06-15

    The objective of this study was to explore the potential of two natural oils (squalene-Sq and grape seed oil-GSO) to prepare biocompatible antioxidant nanostructured lipid carriers-NLCs as a safety and protective formulation for sensitive {beta}-carotene. For this purpose different oil-in-water nanoemulsions stabilized by a combination of alkylpolyoxy ethylene sorbitans, lecithin and a block copolymer, were prepared using a melt high-shear homogenization process. The physico-chemical characteristics of the carotene-loaded NLCs were firstly investigated in detail. The smaller lipid nanoparticles have been obtained by using Tween 20 as main non-ionic surfactant, with average diameters of about 85 nm for GSO and 89 nm for Sq, with a polydispersity index <0.19. The developed carotene-NLCs presented an excellent physical stability with almost all zeta potential values ranging between -29 Division-Sign -40 mV. The differential scanning calorimetry analysis showed that the {beta}-carotene incorporation has led to a perturbation of solid lipid matrix with a less ordered arrangement. By UV-Vis spectroscopy it was evidenced that after encapsulation {beta}-carotene adopts a supramolecular structure demonstrated by appearance of a shoulder at 530 nm related to a {beta}-carotene triplet-triplet absorption. The carotene-NLCs have been also evaluated in terms of in vitro antioxidant properties. The presence of Sq and GSO produced a significant effect on the antioxidant capacity of developed NLCs. The samples prepared with GSO and Tween 80 as main surfactant showed the highest antioxidant activity (AA %) against free oxygen radicals, exhibiting an enhancement of 35 % for loaded NLCs, as comparing to pure carotene. In addition to these properties, the ability of NLCs to manifest antibacterial activity was tested against Escherichiacoli bacteria. The antibacterial analysis shown that loaded-NLCs develop an effective inhibition zone against bacteria growth and it was dependent in a

  2. Five Ochna species have high antibacterial activity and more than ten antibacterial compounds

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    Jacobus N. Eloff

    2012-01-01

    Full Text Available New measures to control infections in humans and other animals are continuously being sought because of the increasing resistance of bacteria to antibiotics. In a wide tree screening survey of the antimicrobial activity of extracts of tree leaves (www.up.ac.za/phyto, Ochna pulchra, a small tree found widely in southern Africa, had good antibacterial activity. We therefore investigated the antibacterial activity of acetone leaf extracts of some other available Ochna spp. Antibacterial activity and the number of antibacterial compounds in acetone leaf extracts of Ochna natalitia, Ochna pretoriensis, O. pulchra, Ochna gamostigmata and Ochna serullata were determined with a tetrazolium violet serial microplate dilution assay and bioautography against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis and Pseudomonas aeruginosa, bacteria commonly associated with nosocomial infections. The percentage yields of the extracts varied from 2.5% to 8%. The minimum inhibitory concentrations of the five species ranged from 40 µg/mL to 1250 µg/mL. E. coli was sensitive to all the extracts. The O. pretoriensis extract was the most active with minimum inhibitory concentrations of 0.065 mg/mL and 0.039 mg/mL against E. coli and E. faecalis, respectively. The O. pretoriensis extract also had the highest total activities of 923 mL/g and 1538 mL/g, indicating that the acetone extract from 1 g of dried plant material could be diluted to 923 mL or 1538 mL and would still kill these bacteria. Based on the bioautography results, the two most active species, O. pretoriensis and O. pulchra, contained at least 10 antibacterial compounds with similar Rf values. Some of these antibacterial compounds were polar and others were non-polar. Variation in the chemical composition of the species

  3. Highly bacterial resistant silver nanoparticles: synthesis and antibacterial activities

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    Chudasama, Bhupendra, E-mail: bnchudasama@gmail.co [Thapar University, School of Physics and Materials Science (India); Vala, Anjana K.; Andhariya, Nidhi; Mehta, R. V. [Bhavnagar University, Department of Physics (India); Upadhyay, R. V. [Charotar University of Science and Technology, P.D. Patel Institute of Applied Sciences (India)

    2010-06-15

    In this article, we describe a simple one-pot rapid synthesis route to produce uniform silver nanoparticles by thermal reduction of AgNO{sub 3} using oleylamine as reducing and capping agent. To enhance the dispersal ability of as-synthesized hydrophobic silver nanoparticles in water, while maintaining their unique properties, a facile phase transfer mechanism has been developed using biocompatible block co-polymer pluronic F-127. Formation of silver nanoparticles is confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV-vis spectroscopy. Hydrodynamic size and its distribution are obtained from dynamic light scattering (DLS). Hydrodynamic size and size distribution of as-synthesized and phase transferred silver nanoparticles are 8.2 {+-} 1.5 nm ({sigma} = 18.3%) and 31.1 {+-} 4.5 nm ({sigma} = 14.5%), respectively. Antimicrobial activities of hydrophilic silver nanoparticles is tested against two Gram positive (Bacillus megaterium and Staphylococcus aureus), and three Gram negative (Escherichiacoli, Proteusvulgaris and Shigellasonnei) bacteria. Minimum inhibitory concentration (MIC) values obtained in the present study for the tested microorganisms are found much better than those reported for commercially available antibacterial agents.

  4. Highly antioxidant carotene-lipid nanocarriers: synthesis and antibacterial activity

    Science.gov (United States)

    Lacatusu, Ioana; Badea, Nicoleta; Ovidiu, Oprea; Bojin, Dionezie; Meghea, Aurelia

    2012-06-01

    The objective of this study was to explore the potential of two natural oils (squalene—Sq and grape seed oil—GSO) to prepare biocompatible antioxidant nanostructured lipid carriers—NLCs as a safety and protective formulation for sensitive β-carotene. For this purpose different oil-in-water nanoemulsions stabilized by a combination of alkylpolyoxy ethylene sorbitans, lecithin and a block copolymer, were prepared using a melt high-shear homogenization process. The physico-chemical characteristics of the carotene-loaded NLCs were firstly investigated in detail. The smaller lipid nanoparticles have been obtained by using Tween 20 as main non-ionic surfactant, with average diameters of about 85 nm for GSO and 89 nm for Sq, with a polydispersity index Escherichia coli bacteria. The antibacterial analysis shown that loaded-NLCs develop an effective inhibition zone against bacteria growth and it was dependent in a higher extent on the liquid lipid and carotene concentrations than on their particle size.

  5. High-frequency underwater plasma discharge application in antibacterial activity

    Science.gov (United States)

    Ahmed, M. W.; Choi, S.; Lyakhov, K.; Shaislamov, U.; Mongre, R. K.; Jeong, D. K.; Suresh, R.; Lee, H. J.

    2017-03-01

    Plasma discharge is a novel disinfection and effectual inactivation approach to treat microorganisms in aqueous systems. Inactivation of Gram-negative Escherichia coli ( E. coli) by generating high-frequency, high-voltage, oxygen (O2) injected and hydrogen peroxide (H2O2) added discharge in water was achieved. The effect of H2O2 dose and oxygen injection rate on electrical characteristics of discharge and E. coli disinfection has been reported. Microbial log reduction dependent on H2O2 addition with O2 injection was observed. The time variation of the inactivation efficiency quantified by the log reduction of the initial E. coli population on the basis of optical density measurement was reported. The analysis of emission spectrum recorded after discharge occurrence illustrated the formation of oxidant species (OH•, H, and O). Interestingly, the results demonstrated that O2 injected and H2O2 added, underwater plasma discharge had fabulous impact on the E. coli sterilization. The oxygen injection notably reduced the voltage needed for generating breakdown in flowing water and escalated the power of discharge pulses. No impact of hydrogen peroxide addition on breakdown voltage was observed. A significant role of oxidant species in bacterial inactivation also has been identified. Furthermore the E. coli survivability in plasma treated water with oxygen injection and hydrogen peroxide addition drastically reduced to zero. The time course study also showed that the retardant effect on E. coli colony multiplication in plasma treated water was favorable, observed after long time. High-frequency underwater plasma discharge based biological applications is technically relevant and would act as baseline data for the development of novel antibacterial processing strategies.

  6. High-frequency underwater plasma discharge application in antibacterial activity

    Science.gov (United States)

    Ahmed, M. W.; Choi, S.; Lyakhov, K.; Shaislamov, U.; Mongre, R. K.; Jeong, D. K.; Suresh, R.; Lee, H. J.

    2017-03-01

    Plasma discharge is a novel disinfection and effectual inactivation approach to treat microorganisms in aqueous systems. Inactivation of Gram-negative Escherichia coli (E. coli) by generating high-frequency, high-voltage, oxygen (O2) injected and hydrogen peroxide (H2O2) added discharge in water was achieved. The effect of H2O2 dose and oxygen injection rate on electrical characteristics of discharge and E. coli disinfection has been reported. Microbial log reduction dependent on H2O2 addition with O2 injection was observed. The time variation of the inactivation efficiency quantified by the log reduction of the initial E. coli population on the basis of optical density measurement was reported. The analysis of emission spectrum recorded after discharge occurrence illustrated the formation of oxidant species (OH•, H, and O). Interestingly, the results demonstrated that O2 injected and H2O2 added, underwater plasma discharge had fabulous impact on the E. coli sterilization. The oxygen injection notably reduced the voltage needed for generating breakdown in flowing water and escalated the power of discharge pulses. No impact of hydrogen peroxide addition on breakdown voltage was observed. A significant role of oxidant species in bacterial inactivation also has been identified. Furthermore the E. coli survivability in plasma treated water with oxygen injection and hydrogen peroxide addition drastically reduced to zero. The time course study also showed that the retardant effect on E. coli colony multiplication in plasma treated water was favorable, observed after long time. High-frequency underwater plasma discharge based biological applications is technically relevant and would act as baseline data for the development of novel antibacterial processing strategies.

  7. High-frequency underwater plasma discharge application in antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, M. W.; Choi, S.; Lyakhov, K.; Shaislamov, U. [Jeju National University, Department of Nuclear and Energy Engineering (Korea, Republic of); Mongre, R. K.; Jeong, D. K. [Jeju National University, Faculty of Biotechnology (Korea, Republic of); Suresh, R.; Lee, H. J., E-mail: hjlee@jejunu.ac.kr [Jeju National University, Department of Nuclear and Energy Engineering (Korea, Republic of)

    2017-03-15

    Plasma discharge is a novel disinfection and effectual inactivation approach to treat microorganisms in aqueous systems. Inactivation of Gram-negative Escherichia coli (E. coli) by generating high-frequency, high-voltage, oxygen (O{sub 2}) injected and hydrogen peroxide (H{sub 2}O{sub 2}) added discharge in water was achieved. The effect of H{sub 2}O{sub 2} dose and oxygen injection rate on electrical characteristics of discharge and E. coli disinfection has been reported. Microbial log reduction dependent on H{sub 2}O{sub 2} addition with O{sub 2} injection was observed. The time variation of the inactivation efficiency quantified by the log reduction of the initial E. coli population on the basis of optical density measurement was reported. The analysis of emission spectrum recorded after discharge occurrence illustrated the formation of oxidant species (OH{sup •}, H, and O). Interestingly, the results demonstrated that O{sub 2} injected and H{sub 2}O{sub 2} added, underwater plasma discharge had fabulous impact on the E. coli sterilization. The oxygen injection notably reduced the voltage needed for generating breakdown in flowing water and escalated the power of discharge pulses. No impact of hydrogen peroxide addition on breakdown voltage was observed. A significant role of oxidant species in bacterial inactivation also has been identified. Furthermore the E. coli survivability in plasma treated water with oxygen injection and hydrogen peroxide addition drastically reduced to zero. The time course study also showed that the retardant effect on E. coli colony multiplication in plasma treated water was favorable, observed after long time. High-frequency underwater plasma discharge based biological applications is technically relevant and would act as baseline data for the development of novel antibacterial processing strategies.

  8. Easily separated silver nanoparticle-decorated magnetic graphene oxide: Synthesis and high antibacterial activity.

    Science.gov (United States)

    Zhang, Huai-Zhi; Zhang, Chang; Zeng, Guang-Ming; Gong, Ji-Lai; Ou, Xiao-Ming; Huan, Shuang-Yan

    2016-06-01

    Silver nanoparticle-decorated magnetic graphene oxide (MGO-Ag) was synthesized by doping silver and Fe3O4 nanoparticles on the surface of GO, which was used as an antibacterial agent. MGO-Ag was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy dispersive X-ray (EDS), X-ray diffraction (XRD), Raman spectroscopy and magnetic property tests. It can be found that magnetic iron oxide nanoparticles and nano-Ag was well dispersed on graphene oxide; and MGO-Ag exhibited excellent antibacterial activity against Escherichia coli and Staphylococcus aureus. Several factors were investigated to study the antibacterial effect of MGO-Ag, such as temperature, time, pH and bacterial concentration. We also found that MGO-Ag maintained high inactivation rates after use six times and can be separated easily after antibacterial process. Moreover, the antibacterial mechanism is discussed and the synergistic effect of GO, Fe3O4 nanoparticles and nano-Ag accounted for high inactivation of MGO-Ag.

  9. Synthesis, Characterization, and Antibacterial Activities of High-Valence Silver Propamidine Nanoparticles

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    Jinran Lee

    2017-07-01

    Full Text Available Diabetic foot ulcer (DFU is becoming more serious concern as it affects 95% of diabetic patients worldwide. It has been shown that the Staphylococcus aureus and other Gram-negative microorganisms are the main reasons behind this disease. Though many antibiotics are presently used to treat the DFU, due to increased bacterial resistance, new alternative therapies are always welcome. To address this alarming issue, we have designed and synthesized the high-valence silver propamidine (Ag(IIPRO complex as well as nanoparticles and characterized both by usual spectroscopic methods. The reverse microemulsion technique has been applied to synthesize Ag(IIPRO nanoparticles and its antibacterial activity has been compared with zero-valence silver nanoparticles (AgNPs with similar size. The antibacterial efficacies of Ag(IIPRO nanoparticles and AgNPs were tested against Gram-negative and Gram -positive organisms responsible for DFU. The newly synthesized high-valence Ag(IIPRO nanoparticles showed higher antibacterial activity compared to silver-only nanoparticles (AgNPs. This study concludes that the high-valence Ag(IIPRO nanoparticles show better antibacterial activity than AgNPs and they may serve as the next generation therapeutic agent for the diabetic wound care.

  10. A High-Throughput Screen Identifies a New Natural Product with Broad-Spectrum Antibacterial Activity

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    Ymele-Leki, Patrick; Cao, Shugeng; Sharp, Jared; Lambert, Kathleen G.; McAdam, Alexander J.; Husson, Robert N.; Tamayo, Giselle; Clardy, Jon; Watnick, Paula I.

    2012-01-01

    Due to the inexorable invasion of our hospitals and communities by drug-resistant bacteria, there is a pressing need for novel antibacterial agents. Here we report the development of a sensitive and robust but low-tech and inexpensive high-throughput metabolic screen for novel antibiotics. This screen is based on a colorimetric assay of pH that identifies inhibitors of bacterial sugar fermentation. After validation of the method, we screened over 39,000 crude extracts derived from organisms that grow in the diverse ecosystems of Costa Rica and identified 49 with reproducible antibacterial effects. An extract from an endophytic fungus was further characterized, and this led to the discovery of three novel natural products. One of these, which we named mirandamycin, has broad-spectrum antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Vibrio cholerae, methicillin-resistant Staphylococcus aureus, and Mycobacterium tuberculosis. This demonstrates the power of simple high throughput screens for rapid identification of new antibacterial agents from environmental samples. PMID:22359585

  11. In vitro antibacterial activity of seven Indian spices against high level gentamicin resistant strains of enterococci

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    Bipin, Chapagain; Chitra, Pai (Bhat); Minakshi, Bhattacharjee

    2015-01-01

    Introduction The aim of the study was to explore the in vitro antibacterial activity of seven ethanolic extracts of spices against high level gentamicin resistant (HLGR) enterococci isolated from human clinical samples. Material and methods Two hundred and fifteen enterococcal strains were isolated from clinical samples. High level gentamicin resistance in ethanolic extracts of cumin (Cuminum cyminum), cinnamon (Cinnamomum zeylanicum), ginger (Zingiber officinale), fenugreek (Trigonella foenum-graecum), cloves (Syzygium aromaticum), cardamom (Elettaria cardamomum Maton) and black pepper (Piper nigrum) were prepared using Soxhlet apparatus. The antibacterial effect of the extracts was studied using the well diffusion method. Statistical analysis was carried out by χ2 test using SPSS 17 software. Results Only cinnamon and ginger were found to have activity against all the isolates, whereas cumin and cloves had a variable effect on the strains. Fenugreek, black pepper and cardamom did not show any effect on the isolates. The zone diameter of inhibition obtained for cinnamon, ginger, cloves and cumin was in the range 31–34 mm, 27–30 mm, 25–26 mm and 19–20 mm respectively. Conclusions Cinnamomum zeylanicum and Z. officinale showed the maximum antibacterial activity against the enterococcal isolates followed by S. aromaticum and C. cyminum. The findings of the study show that spices used in the study can contribute to the development of potential antimicrobial agents for inclusion in the anti-enterococcal treatment regimen. PMID:26322099

  12. Highly water-dispersible silver sulfadiazine decorated with polyvinyl pyrrolidone and its antibacterial activities

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ping; Wu, Longlong [Key Laboratory for Special Functional Materials, Henan University, Kaifeng 475004 (China); Li, Binjie, E-mail: lbj821@163.com [Key Laboratory for Special Functional Materials, Henan University, Kaifeng 475004 (China); Medical School of Henan University, Kaifeng 475004 (China); Zhao, Yanbao [Key Laboratory for Special Functional Materials, Henan University, Kaifeng 475004 (China); Qu, Peng [Department of Chemistry, Shangqiu Normal University, Shangqiu 476000 (China)

    2016-03-01

    Highly water-dispersible silver sulfadiazine (SSD) was prepared by liquid phase method with polyvinyl pyrrolidone (PVP) as a surface modification agent. The structure and morphology of the PVP-modified silver sulfadiazine (P-SSD) were investigated by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Fourier-transform infrared (FT-IR) spectrometry. The produced particles are ginkgo leaf-like architecture with the sizes of micron-nanometer. Due to hydrophilic PVP decorated on the surface, the P-SSD has excellent dispersion in water over a period of 24 h, which is obviously stable by comparison to that of the commercial silver sulfadiazine (C-SSD). In addition, the P-SSD exhibits good antibacterial activities against Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). - Highlights: • Polyvinyl pyrrolidone decorated silver sulfadiazine was synthesized via a one-pot protocol. • The produced particles present ginkgo leaf-like architectures with sizes of micro-nanometer. • The resulted silver sulfadiazine has highly dispersible in water over a period of 24 h. • The obtained sliver sulfadiazine exhibits excellent antibacterial activities against E. coli, P. aeruginosa and S. aureus.

  13. I-TiO2/PVC film with highly photocatalytic antibacterial activity under visible light.

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    Deng, Weihua; Ning, Shangbo; Lin, Qianying; Zhang, Hualei; Zhou, Tanghua; Lin, Huaxiang; Long, Jinlin; Lin, Qun; Wang, Xuxu

    2016-08-01

    Iodine-modified TiO2(I-TiO2) film were coated on medical-grade PVC material by impregnation-deposition method and subsequently characterized by XRD, SEM, TEM, AFM, DRS and XPS. The photocatalytic anti-bacterial activity of I-TiO2/PVC was investigated both by in vitro anti-bacterial experiments and by clinical study. The results revealed that I-TiO2/PVC exhibit excellent photocatalytic antibacterial activity, which can destroy the propagation of the Escherichia coli and cause the deactivation and death of most E. coli bacteria within 30min visible light illumination. Clinical study on animals showed that I-TiO2 coated on PVC decrease the formation of biofilm on PVC surface in the mechanical ventilation. Furthermore, I-TiO2/PVC can effectively reduce inflammation of tracheal tissue of bam suckling pig and prevents the occurrence of VAP.

  14. Bifunctional Therapeutic High-Valence Silver-Pyridoxine Nanoparticles with Proliferative and Antibacterial Wound-Healing Activities.

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    Rangasamy, Sabarinathan; Tak, Yu Kyung; Kim, Sunhee; Paul, Avijit; Song, Joon Myong

    2016-01-01

    The antibacterial and moisturizing effects inherent to silver nanoparticles contribute greatly to their use as a topical antibacterial agent. The antibacterial property of silver nanoparticles provides topical wounds with an indirect environment for healing through the prevention of pathogenic infection. However, the direct wound-healing effects of silver nanoparticles have not been previously explored. In this work, we report a bimodal therapeutic silver nanoparticle that possesses both direct wound-healing and antibacterial properties. The nanoparticles consist of high-valence silver-pyridoxine complexes. The wound-healing efficacy was verified in diabetic mice, as well as in vitro assays. A MAPK pathway study demonstrated that silver-pyridoxine nanoparticles induced the proliferation and migration of keratinocyte and fibroblast cells. Antibacterial activities in 8 different pathogenic bacteria responsible for the infection of burn wounds were tested. The rapid wound healing occurring on skin wounds of diabetic mice attests to the utility of bimodal therapeutic silver nanoparticles as a next-generation topical therapeutic agent.

  15. New Derivatives of Pyridoxine Exhibit High Antibacterial Activity against Biofilm-Embedded Staphylococcus Cells.

    Science.gov (United States)

    Kayumov, Airat R; Nureeva, Aliya A; Trizna, Elena Yu; Gazizova, Guzel R; Bogachev, Mikhail I; Shtyrlin, Nikita V; Pugachev, Mikhail V; Sapozhnikov, Sergey V; Shtyrlin, Yurii G

    2015-01-01

    Opportunistic bacteria Staphylococcus aureus and Staphylococcus epidermidis often form rigid biofilms on tissues and inorganic surfaces. In the biofilm bacterial cells are embedded in a self-produced polysaccharide matrix and thereby are inaccessible to biocides, antibiotics, or host immune system. Here we show the antibacterial activity of newly synthesized cationic biocides, the quaternary ammonium, and bisphosphonium salts of pyridoxine (vitamin B6) against biofilm-embedded Staphylococci. The derivatives of 6-hydroxymethylpyridoxine were ineffective against biofilm-embedded S. aureus and S. epidermidis at concentrations up to 64 μg/mL, although all compounds tested exhibited low MICs (2 μg/mL) against planktonic cells. In contrast, the quaternary ammonium salt of pyridoxine (N,N-dimethyl-N-((2,2,8-trimethyl-4H-[1,3]dioxino[4,5-c]pyridin-5-yl)methyl)octadecan-1-aminium chloride (3)) demonstrated high biocidal activity against both planktonic and biofilm-embedded bacteria. Thus, the complete death of biofilm-embedded S. aureus and S. epidermidis cells was obtained at concentrations of 64 and 16 μg/mL, respectively. We suggest that the quaternary ammonium salts of pyridoxine are perspective to design new synthetic antibiotics and disinfectants for external application against biofilm-embedded cells.

  16. New Derivatives of Pyridoxine Exhibit High Antibacterial Activity against Biofilm-Embedded Staphylococcus Cells

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    Airat R. Kayumov

    2015-01-01

    Full Text Available Opportunistic bacteria Staphylococcus aureus and Staphylococcus epidermidis often form rigid biofilms on tissues and inorganic surfaces. In the biofilm bacterial cells are embedded in a self-produced polysaccharide matrix and thereby are inaccessible to biocides, antibiotics, or host immune system. Here we show the antibacterial activity of newly synthesized cationic biocides, the quaternary ammonium, and bisphosphonium salts of pyridoxine (vitamin B6 against biofilm-embedded Staphylococci. The derivatives of 6-hydroxymethylpyridoxine were ineffective against biofilm-embedded S. aureus and S. epidermidis at concentrations up to 64 μg/mL, although all compounds tested exhibited low MICs (2 μg/mL against planktonic cells. In contrast, the quaternary ammonium salt of pyridoxine (N,N-dimethyl-N-((2,2,8-trimethyl-4H-[1,3]dioxino[4,5-c]pyridin-5-ylmethyloctadecan-1-aminium chloride (3 demonstrated high biocidal activity against both planktonic and biofilm-embedded bacteria. Thus, the complete death of biofilm-embedded S. aureus and S. epidermidis cells was obtained at concentrations of 64 and 16 μg/mL, respectively. We suggest that the quaternary ammonium salts of pyridoxine are perspective to design new synthetic antibiotics and disinfectants for external application against biofilm-embedded cells.

  17. Calcium phosphate coating containing silver shows high antibacterial activity and low cytotoxicity and inhibits bacterial adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Yoshiki, E-mail: andoy@jmmc.jp [Division of Microbiology, Department of Pathology and Microbiology, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan); Research Department, Japan Medical Materials Corporation, Uemura Nissei Bldg.9F 3-3-31 Miyahara, Yodogawa-ku, Osaka 532-0003 (Japan); Miyamoto, Hiroshi [Division of Microbiology, Department of Pathology and Microbiology, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan); Noda, Iwao; Sakurai, Nobuko [Research Department, Japan Medical Materials Corporation, Uemura Nissei Bldg.9F 3-3-31 Miyahara, Yodogawa-ku, Osaka 532-0003 (Japan); Akiyama, Tomonori [Division of Microbiology, Department of Pathology and Microbiology, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan); Yonekura, Yutaka; Shimazaki, Takafumi; Miyazaki, Masaki; Mawatari, Masaaki; Hotokebuchi, Takao [Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501 (Japan)

    2010-01-01

    Surgical site infection is one of the serious complications of orthopedic implants. In order to reduce the incidence of implant-associated infections, we developed a novel coating technology of calcium phosphate (CP) containing silver (Ag), designated Ag-CP coating, using a thermal spraying technique. In this study, we evaluated the antibacterial efficacy and biological safety of this coating. In vitro antibacterial activity tests showed that the growths of Escherichia coli, Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) are completely suppressed on Ag-CP coating. In vitro bacterial adherence tests revealed that the number of adherent bacteria on the surface of this coating is significantly less (p < 0.02) than that on the surface of the CP coating. Moreover, the Ag-CP coating completely inhibits MRSA adhesion [<10 colony-forming units (CFU)] when 10{sup 2} CFU MRSA is inoculated. On the other hand, V79 Chinese hamster lung cells were found to grow on the Ag-CP coating as well as on the CP coating in a cytotoxicity test. These results indicate that the Ag-CP coating on the surface of orthopedic implants exhibits antibacterial activity and inhibits bacterial adhesion without cytotoxicity.

  18. Surface activation of graphene oxide nanosheets by ultraviolet irradiation for highly efficient anti-bacterials

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    Veerapandian, Murugan; Zhang, Linghe; Krishnamoorthy, Karthikeyan; Yun, Kyusik

    2013-10-01

    A comprehensive investigation of anti-bacterial properties of graphene oxide (GO) and ultraviolet (UV) irradiated GO nanosheets was carried out. Microscopic characterization revealed that the GO nanosheet-like structures had wavy features and wrinkles or thin grooves. Fundamental surface chemical states of GO nanosheets (before and after UV irradiation) were investigated using x-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. Minimum inhibitory concentration (MIC) results revealed that UV irradiated GO nanosheets have more pronounced anti-bacterial behavior than GO nanosheets and standard antibiotic, kanamycin. The MIC of UV irradiated GO nanosheets was 0.125 μg ml-1 for Escherichia coli and Salmonella typhimurium, 0.25 μg ml-1 for Bacillus subtilis and 0.5 μg ml-1 for Enterococcus faecalis, ensuring its potential as an anti-infective agent for controlling the growth of pathogenic bacteria. The minimum bactericidal concentration of normal GO nanosheets was determined to be two-fold higher than its corresponding MIC value, indicating promising bactericidal activity. The mechanism of anti-bacterial action was evaluated by measuring the enzymatic activity of β-d-galactosidase for the hydrolysis of o-nitrophenol-β-d-galactopyranoside.

  19. Antibacterial Activity of Geminized Amphiphilic Cationic Homopolymers.

    Science.gov (United States)

    Wang, Hui; Shi, Xuefeng; Yu, Danfeng; Zhang, Jian; Yang, Guang; Cui, Yingxian; Sun, Keji; Wang, Jinben; Yan, Haike

    2015-12-22

    The current study is aimed at investigating the effect of cationic charge density and hydrophobicity on the antibacterial and hemolytic activities. Two kinds of cationic surfmers, containing single or double hydrophobic tails (octyl chains or benzyl groups), and the corresponding homopolymers were synthesized. The antimicrobial activity of these candidate antibacterials was studied by microbial growth inhibition assays against Escherichia coli, and hemolysis activity was carried out using human red blood cells. It was interestingly found that the homopolymers were much more effective in antibacterial property than their corresponding monomers. Furthermore, the geminized homopolymers had significantly higher antibacterial activity than that of their counterparts but with single amphiphilic side chains in each repeated unit. Geminized homopolymers, with high positive charge density and moderate hydrophobicity (such as benzyl groups), combine both advantages of efficient antibacterial property and prominently high selectivity. To further explain the antibacterial performance of the novel polymer series, the molecular interaction mechanism is proposed according to experimental data which shows that these specimens are likely to kill microbes by disrupting bacterial membranes, leading them unlikely to induce resistance.

  20. The antibacterial activity of diluted Tualang honey

    Directory of Open Access Journals (Sweden)

    N. A. Roslan

    2015-05-01

    Full Text Available Tualang honey (TH is a Malaysian jungle honey obtained from the wild. The honey is produced by the rock bee (Apis dorsata, which builds hives on branches of tall Tualang (Koompassia excelsa (Becc. Taub trees located mainly in the north-western region of Peninsular Malaysia. Limited information is available on the antibacterial mechanism of local honey. The present study was conducted to determine the antibacterial activity of diluted ?Tualang? honey against Escherichia coli (E. coli. Three different Tualang honey concentrations, namely, 20, 30 and 40% were used to examine the effect of diluting Tualang honey on its antibacterial effect towards E. coli. The 40% diluted honey was the most effective in inhibiting the growth of E. coli, followed by honey diluted at 20 and 30%. The high antibacterial activity of honey towards E. Coli was thought to arise from the production of hydrogen peroxide, but requires further study to validate the action.

  1. Synthesis, crystal structure and antibacterial activity of new highly functionalized ionic compounds based on the imidazole nucleus.

    Science.gov (United States)

    Bahnous, Mebarek; Bouraiou, Abdelmalek; Chelghoum, Meryem; Bouacida, Sofiane; Roisnel, Thierry; Smati, Farida; Bentchouala, Chafia; Gros, Philippe C; Belfaitah, Ali

    2013-03-01

    Several new highly functionalized imidazolium derivatives were synthesized, via appropriate synthetic routes, using imidazole, 1-methylimidazole and 2-phenyl-1-methylimidazole as key intermediates. The antibacterial activity of the prepared compounds was evaluated against: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella thipymurium using disk-diffusion and MIC methods. Crystal X-ray structures are reported for six compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Antibacterial activity in vitro of Thymus capitatus from Jordan.

    Science.gov (United States)

    Qaralleh, Haitham N; Abboud, Muayad M; Khleifat, Khaled M; Tarawneh, Khaled A; Althunibat, Osama Y

    2009-07-01

    This study was carried out to evaluate the antibacterial activity of aqueous and organic extracts of Thymus capitatus L. (Lamiaceae) leaves and stems. Dried ground powder leaves and stems were extracted with water (aqueous extracts), ethanol, dichloromethane and hexane (Soxhlet extracts). The antibacterial activity of these extracts was evaluated against bacteria using disc diffusion method. The result obtained showed that the leaves had stronger antibacterial activity than the stems extracts. The ethanolic extract had the highest yield products and the high antibacterial activity than all other solvents. The results suggest that essential oil as non-polar organic compounds could be the main active compounds in this plant. Therefore the antibacterial activity of leaves ethanol extracts (LEE) was compared with essential oils leaves extracts (LEO) of T. capitatus. The LEO showed greater antibacterial activity than LEE. The LEO showed a broad spectrum of antibacterial activity and the Pseudomonas aeruginosa was the most sensitive bacteria.

  3. Antibacterial activity of amphiphilic tobramycin.

    Science.gov (United States)

    Dhondikubeer, Ramesh; Bera, Smritilekha; Zhanel, George G; Schweizer, Frank

    2012-10-01

    Amphiphilic aminoglycoside antimicrobials are an emerging class of new antibacterial agents with novel modes of action. Previous studies have shown that amphiphilic neomycin-B and kanamycin-A analogs restore potent antibacterial activity against Gram-positive neomycin-B- and kanamycin-A-resistant organisms. In this paper, we investigated the antibacterial properties of a series of amphiphilic tobramycin analogs. We prepared tobramycin-lipid conjugates, as well as tobramycin-peptide triazole conjugates, and studied their antibacterial activities against a panel of Gram-positive and Gram-negative bacterial strains, including isolates obtained from Canadian hospitals. Our results demonstrate that the antibacterial activity of amphiphilic tobramycin is greatly affected by the length and nature of the hydrophobic lipid tail, whereas the nature of the polycationic headgroup or the number of cationic charges appear to be less important. Replacement of the hydrophobic tail by a fluorinated lipid confers good activity against two Pseudomonas strains and reduces hemolytic activity. However, susceptibility studies in the presence of bovine serum albumin indicate that all amphiphilic tobramycin analogs are strongly protein-bound, leading to a typical four- to eight-fold increase in MIC.

  4. Antibacterial activity of Pterocarpus indicus.

    Science.gov (United States)

    Khan, M R; Omoloso, A D

    2003-09-01

    The leaves, root and stem barks of Pterocarpus indicus were successively partitioned with petrol, dichloromethane, ethyl acetate, butanol and methanol. All the fractions exhibited a wide spectrum of antibacterial activity. The activity was more pronounced in the butanol and methanol fractions. None were active against the moulds.

  5. Antibacterial activity of epidural infusions.

    Science.gov (United States)

    Coghlan, M W; Davies, M J; Hoyt, C; Joyce, L; Kilner, R; Waters, M J

    2009-01-01

    The incidence of epidural abscess following epidural catheterisation appears to be increasing, being recently reported as one in 1000 among surgical patients. This study was designed to investigate the antibacterial activity of various local anaesthetics and additives, used in epidural infusions, against a range of micro-organisms associated with epidural abscess. The aim was to determine which, if any, epidural infusion solution has the greatest antibacterial activity. Bupivacaine, ropivacaine and levobupivacaine crystals were dissolved and added to Mueller-Hinton Agar in concentrations of 0.06%, 0.125%, 0.2%, 0.25%, 0.5% and 1%. Fentanyl, adrenaline and clonidine were also mixed with agar in isolation and in combination with the local anaesthetics. Using a reference agar dilution method, the minimum inhibitory concentrations were determined for a range of bacteria. Bupivacaine showed antibacterial activity against Staphylococcus aureus, Enterococcus faecalis and Escherichia coli with minimum inhibitory concentrations between 0.125% and 0.25%. It did not inhibit the growth of Pseudomonas aeruginosa at any of the concentrations tested. Levobupivacaine and ropivacaine showed no activity against Staphylococcus aureus, Enterococcus faecalis and Pseudomonas aeruginosa, even at the highest concentrations tested, and minimal activity against Escherichia coli (minimum inhibitory concentrations 0.5% and 1% respectively). The presence of fentanyl, adrenaline and clonidine had no additional effect on the antibacterial activity of any of the local anaesthetic agents. The low concentrations of local anaesthetic usually used in epidural infusions have minimal antibacterial activity. While the clinical implications of this in vitro study are not known, consideration should be given to increasing the concentration of bupivacaine in an epidural infusion or to administering a daily bolus of 0.25% bupivacaine to reduce the risk of epidural bacterial growth.

  6. The highly synergistic, broad spectrum, antibacterial activity of organic acids and transition metals

    Science.gov (United States)

    Zhitnitsky, Daniel; Rose, Jessica; Lewinson, Oded

    2017-01-01

    For millennia, transition metals have been exploited to inhibit bacterial growth. We report here the potentiation of the anti-bacterial activity of transition metals by organic acids. Strong synergy between low, non-toxic concentrations of transition metals and organic acids was observed with up to ~1000-fold higher inhibitory effect on bacterial growth. We show that organic acids shuttle transition metals through the permeability barrier of the bacterial membrane, leading to increased influx of transition metals into bacterial cells. We demonstrate that this synergy can be effectively used to inhibit the growth of a broad range of plant and human bacterial pathogens, and suggest that a revision of food preservation and crop protection strategies may be in order. These findings bear significant biomedical, agricultural, financial and environmental opportunities. PMID:28294164

  7. Synthesis and Antibacterial Activities of Erythromycin Derivatives

    Institute of Scientific and Technical Information of China (English)

    FENG Run-liang; GONG Ping; FANG Lin; HONG Wei

    2005-01-01

    Ten new erythromycin antibacterial agents containing amidino group were designed and synthesized from erythromycin via oximation, reduction and condensation. Their structures were confirmed by MS and 13C NMR; the synthetic condition(reaction medium)was explored; and their in vtiro antibacterial activities were tested. Compound HMA-3 showed antibacterial activity against staphylococcus aureus, which is equivalent to that of erythromycin A. Compounds HMA-8 and HMA-4 also showed an antibacterial activitiy. But no compound showed bactericidal activity.

  8. Salicylanilide carbamates: Promising antibacterial agents with high in vitro activity against methicillin-resistant Staphylococcus aureus (MRSA).

    Science.gov (United States)

    Zadrazilova, Iveta; Pospisilova, Sarka; Masarikova, Martina; Imramovsky, Ales; Ferriz, Juana Monreal; Vinsova, Jarmila; Cizek, Alois; Jampilek, Josef

    2015-09-18

    A series of twenty-one salicylanilide N-alkylcarbamates was assessed for novel antibacterial characteristics against three clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus ATCC 29213 as the reference and quality control strain. The minimum inhibitory concentration was determined by the broth dilution micro-method with subsequent subcultivation of aliquots to assess minimum bactericidal concentration. The bactericidal kinetics was established by time-kill assay. Ampicillin, ciprofloxacin and vancomycin were used as reference antibacterial drugs. All the tested compounds exhibited highly potent anti-MRSA activity (⩽ 0.008-4 μg/mL) comparable or up to 250× higher than that of vancomycin, the standard in the treatment of serious MRSA infections. 4-Chloro-2-(3,4-dichlorophenylcarbamoyl)phenyl butylcarbamate and 4-chloro-2-(3,4-dichlorophenylcarbamoyl)phenyl ethylcarbamate were the most active compounds. In most cases, compounds provided reliable bacteriostatic activity, except for 4-chloro-2-(4-chlorophenylcarbamoyl)phenyl decylcarbamate exhibiting bactericidal effect at 8h (for clinical isolate of MRSA 63718) and at 24h (for clinical isolates of MRSA SA 630 and MRSA SA 3202) at 4× MIC. Structure-activity relationships are discussed.

  9. Ultrasmall, Ligand-Free Ag Nanoparticles with High Antibacterial Activity Prepared by Pulsed Laser Ablation in Liquid

    Directory of Open Access Journals (Sweden)

    László Kőrösi

    2016-01-01

    Full Text Available Since ancient times, silver and its compounds have been known to have a broad spectrum of antimicrobial activities for bacteria, fungi, and viruses. Due to the increasing bacterial resistance to classic antibiotics, the investigations of Ag NPs have increased. Herein, we present the preparation of ligand-free Ag NPs with 3 and 20 nm sizes by applying picosecond laser ablation in liquid at 355 and 1065 nm. Our laser processing system allows a high control on particle sizes. The produced nanoparticles were characterized by means of transmission electron microscopy, UV-Vis spectroscopy, and X-ray diffraction. The size effect on the antibacterial activity of Ag NPs was tested against E. coli and S. aureus. The growth curves of bacteria were monitored at 0–5 mg/L of Ag NPs by a multimode microplate reader. The size effects as well as the concentration of Ag NPs on their antibacterial activity are discussed.

  10. Hierarchical-structured anatase-titania/cellulose composite sheet with high photocatalytic performance and antibacterial activity.

    Science.gov (United States)

    Luo, Yan; Huang, Jianguo

    2015-02-02

    Bulk hierarchical anatase-titania/cellulose composite sheets were fabricated by subjecting an ultrathin titania gel film pre-deposited filter paper to a solvo-co-hydrothermal treatment by using titanium butoxide as the precursor to grow anatase-titania nanocrystallites on the cellulose nanofiber surfaces. The titanium butoxide specie is firstly absorbed onto the nanofibers of the cellulose substance through a solvothermal process, which was thereafter hydrolyzed and crystallized upon the subsequent hydrothermal treatment, leading to the formation of fine anatase-titania nanoparticles with sizes of 2-5 nm uniformly anchored on the cellulose nanofibers. The resulting anatase-titania/cellulose composite sheet shows a significant photocatalytic performance towards degradation of a methylene blue dye, and introduction of silver nanoparticles into the composite sheet yields an Ag-NP/anatase-titania/cellulose composite material possessing excellent antibacterial activity against both Gram-positive and Gram-negative bacteria. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Antiproliferative and antibacterial activity evaluation of red ...

    African Journals Online (AJOL)

    sunny

    2014-10-22

    Oct 22, 2014 ... Key words: Rhodosorus marinus, red microalgae, antibacterial activity, antiproliferative activity, methanolic extract. ... subsequent production of metabolites (secondary ..... antioxidant molecules, such as vitamins, enzymes,.

  12. [Antibacterial activity of some lichens from southern Spain].

    Science.gov (United States)

    Rowe, J G; Saenz, M T; Garcia, M D

    1989-01-01

    Antibacterial activity of some lichens from south Spain has been studied. High activity against Gram+ bacteria has been observed, although Parmelia caperata, Evernia prunastri and Usnea sp. are also active against Gram- bacteria.

  13. Antibacterial and leishmanicidal activity of Bolivian propolis.

    Science.gov (United States)

    Nina, N; Lima, B; Feresin, G E; Giménez, A; Salamanca Capusiri, E; Schmeda-Hirschmann, G

    2016-03-01

    The antimicrobial activity of Bolivian propolis was assessed for the first time on a panel of bacteria and two endemic parasitic protozoa. Ten samples of Bolivian propolis and their main constituents were tested using the micro-broth dilution method against 11 bacterial pathogenic strains as well as against promastigotes of Leishmania amazonensis and L. braziliensis using the XTT-based colorimetric method. The methanolic extracts showed antibacterial effect ranging from inactive (MICs > 1000 μg ml(-1) ) to low (MICs 250-1000 μg ml(-1) ), moderate (62·5-125 μg ml(-1) ) and high antibacterial activity (MIC 31·2 μg ml(-1) ), according to the collection place and chemical composition. The most active samples towards Leishmania species were from Cochabamba and Tarija, with IC50 values of 12·1 and 7·8, 8·0 and 10·9 μg ml(-1) against L. amazonensis and Leishmania brasiliensis respectively. The results show that the best antibacterial and antiprotozoal effect was observed for some phenolic-rich propolis. Propolis is used in Bolivia as an antimicrobial agent. Bolivian propolis from the main production areas was assessed for antibacterial and leishmanicidal effect and the results were compared with the propolis chemical composition. The active antibacterial propolis samples were phenolic-rich while those containing mainly triterpenes were devoid of activity or weakly active. A similar picture was obtained for the effect on Leishmania, with better effect for the phenolic-rich samples. As propolis is used for the same purposes regardless of the production area and composition, our findings indicate the need for the standardization of this natural product as antimicrobial. © 2016 The Society for Applied Microbiology.

  14. Antibacterial Activity of Grepafloxacin

    Directory of Open Access Journals (Sweden)

    B Wiedemann

    1998-01-01

    Full Text Available Grepafloxin has an extremely broad spectrum of activity. Its activity against Gram-positive bacteria exceeds that of currently available quinolones. Grepafloxacin-resistant mutants seem to occur less frequently than ciprofloxacin - or ofloxacin-resistant mutants, and the increase in minimum inhibitory concentration (MIC against the former mutants is less than that of the latter. This applies only to the relative differences (in dilution steps; the absolute values are similar. Grepafloxacin kills Gram-positive bacteria at concentrations little above the MIC. Its pharmacodynamic profile against pneumococci is promising, favouring use of this drug for respiratory tract infections.

  15. Prediction Model of Antibacterial Activities for Inorganic Antibacterial Agents Based on Artificial Neural Networks

    Institute of Scientific and Technical Information of China (English)

    刘雪峰; 张利; 涂铭旌

    2004-01-01

    Quantitatively evaluation of antibacterial activities of inorganic antibacterial agents is an urgent problem to be solved. Using experimental data by an orthogonal design, a prediction model of the relation between conditions of preparing inorganic antibacterial agents and their antibacterial activities has been developed. This is accomplished by introducing BP artificial neural networks in the study of inorganic antibacterial agents..It provides a theoretical support for the development and research on inorganic antibacterial agents.

  16. Modified Silica Nanofibers with Antibacterial Activity

    Directory of Open Access Journals (Sweden)

    Ivana Veverková

    2016-01-01

    Full Text Available This study is focused on development of functionalized inorganic-organic nanofibrous material with antibacterial activity for wound dressing applications. The nanofibers combining poly(vinyl alcohol and silica were produced by electrospinning from the sol and thermally stabilized. The PVA/silica nanofibers surface was functionalized by silver and copper nanoparticles to ensure antibacterial activity. It was proven that quantity of adsorbed silver and copper nanoparticles depends on process time of adsorption. According to antibacterial tests results, this novel nanofibrous material shows a big potential for wound dressing applications due to its significant antibacterial efficiency.

  17. Antibacterial Activity of Silicate Bioceramics

    Institute of Scientific and Technical Information of China (English)

    HU Sheng; NING Congqin; ZHOU Yue; CHEN Lei; LIN Kaili; CHANG Jiang

    2011-01-01

    Four kinds of pure silicate ceramic particles, CaSiO3, Ca3SiO5, bredigite and akermanite were prepared and their bactericidal effects were systematically investigated. The phase compositions of these silicate ceramics were characterized by XRD. The ionic concentration meas urement revealed that the Calcium (Ca) ion concentration were relatively higher in Ca3SiO5 and bredigite, and much lower in CaSiO3 and akermanite. Accordingly, the pH values of the four silicate ceramics extracts showed a positive correlation with the particle concentrations. Meanwhile, by decreasing the particle size, higher Ca ion concentrations can be achieved, leading to the increase of aqueous pH value as well. In summary, all of the four silicate ceramics tested in our study showed antibacterial effect in a dose-dependent manner. Generally, the order of their antibacterial activity against E.coli from strong to weak is Ca3SiO5, bredigite, CaSiO3 and akermanite.

  18. Superior antibacterial activity of zinc oxide/graphene oxide composites originating from high zinc concentration localized around bacteria.

    Science.gov (United States)

    Wang, Yan-Wen; Cao, Aoneng; Jiang, Yu; Zhang, Xin; Liu, Jia-Hui; Liu, Yuanfang; Wang, Haifang

    2014-02-26

    New materials with good antibacterial activity and less toxicity to other species attract numerous research interest. Taking advantage of zinc oxide (ZnO) and graphene oxide (GO), the ZnO/GO composites were prepared by a facile one-pot reaction to achieve superior antibacterial properties without damaging other species. In the composites, ZnO nanoparticles (NPs), with a size of about 4 nm, homogeneously anchored onto GO sheets. The typical bacterium Escherichia coli and HeLa cell were used to evaluate the antibacterial activity and cytotoxicity of the ZnO/GO composites, respectively. The synergistic effects of GO and ZnO NPs led to the superior antibacterial activity of the composites. GO helped the dispersion of ZnO NPs, slowed the dissolution of ZnO, acted as the storage site for the dissolved zinc ions, and enabled the intimate contact of E. coli with ZnO NPs and zinc ions as well. The close contact enhanced the local zinc concentration pitting on the bacterial membrane and the permeability of the bacterial membrane and thus induced bacterial death. In addition, the ZnO/GO composites were found to be much less toxic to HeLa cells, compared to the equivalent concentration of ZnO NPs in the composites. The results indicate that the ZnO/GO composites are promising disinfection materials to be used in surface coatings on various substrates to effectively inhibit bacterial growth, propagation, and survival in medical devices.

  19. Antibacterial activity of Parmelia perlata

    Institute of Scientific and Technical Information of China (English)

    Alwar Vidyalakshmi; Kandaswamy Kruthika

    2012-01-01

    Objective: To test efficacy of Parmelia perlata (P. perlata), which is used in traditional medicine for rapid wound healing against test bacteria that cause wound infections. Methods: Different solvents such as methanol, ethyl acetate and acetone were used for extraction of P. perlata. The sensitivity of the test bacteria to solvent extracts of P. perlata was tested by measuring the zone of inhibition on growth media and by determining the minimal inhibitory concentration and minimal bactericidal concentration. Results: Methanol, ethyl acetate and acetone extracts of P.perlata have shown inhibitory activity against Staphylococcus aureus (S.aureus). Conclusions: The results of the present study indicate that P. perlata has potential antibacterial compounds againstS.aureus that causes multitude of skin infections among human beings. Development of drugs from natural compounds can help us to combat antibiotic-resistant bacteria.

  20. Storage stability and antibacterial activity of eugenol nanoliposomes prepared by an ethanol injection-dynamic high-pressure microfluidization method.

    Science.gov (United States)

    Peng, Shengfeng; Zou, Liqiang; Liu, Wei; Gan, Lu; Liu, Weilin; Liang, Ruihong; Liu, Chengmei; Niu, Jing; Cao, Yanlin; Liu, Zhen; Chen, Xing

    2015-01-01

    Eugenol is a major phenolic component with diverse biological activities. However, it is difficult to formulate into an aqueous solution due to poor water solubility, and this limits its application. In the present study, eugenol nanoliposomes (EN) were prepared by combining the ethanol injection method with the dynamic high-pressure microfluidization method. Good physicochemical characterizations of EN were obtained. The successful encapsulation of eugenol in nanoliposomes was confirmed by Fourier transform infrared spectroscopy. A good storage stability of EN was confirmed by its low variation of average particle diameter and encapsulation efficiency after 8 weeks of storage. No oil drops were found in EN after 8 weeks of storage at 4°C and at room temperature, which suggested that the poor water solubility of eugenol was overcome by nanoliposome encapsulation. Compared with that of eugenol solution, a relatively good sustained release property was observed in EN. The antibacterial activity of EN against four common foodborne pathogenic bacteria (Staphylococcus aureus, Escherichia coli, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes) was evaluated in both Luria broth and milk medium.

  1. Synthesis, Characterization and Antibacterial Activity of Imidazole ...

    African Journals Online (AJOL)

    NICO

    Antibacterial activity of the ligands and their metal complexes were tested ... through appropriate substition on the phenanthroline rings.17,18. Firstly, we synthesized ..... groups to the phenanthroline ring due to electron flow from the nitrogen ...

  2. Highly stable and re-dispersible nano Cu hydrosols with sensitively size-dependent catalytic and antibacterial activities

    Science.gov (United States)

    Zhang, Yu; Zhu, Pengli; Li, Gang; Wang, Wenzhao; Chen, Liang; Lu, Daoqiang Daniel; Sun, Rong; Zhou, Feng; Wong, Chingping

    2015-08-01

    Highly stable monodispersed nano Cu hydrosols were facilely prepared by an aqueous chemical reduction method through selecting copper hydroxide (Cu(OH)2) as the copper precursor, poly(acrylic acid) (PAA) and ethanol amine (EA) as the complexing agents, and hydrazine hydrate as the reducing agent. The size of the obtained Cu colloidal nanoparticles was controlled from 0.96 to 26.26 nm by adjusting the dosage of the copper precursor. Moreover, the highly stable nano Cu hydrosols could be easily concentrated and re-dispersed in water meanwhile maintaining good dispersibility. A model catalytic reaction of reducing p-nitrophenol with NaBH4 in the presence of nano Cu hydrosols with different sizes was performed to set up the relationship between the apparent kinetic rate constant (kapp) and the particle size of Cu catalysts. The experimental results indicate that the corresponding kapp showed an obvious size-dependency. Calculations revealed that kapp was directly proportional to the surface area of Cu catalyst nanoparticles, and also proportional to the reciprocal of the particle size based on the same mass of Cu catalysts. This relationship might be a universal principle for predicting and assessing the catalytic efficiency of Cu nanoparticles. The activation energy (Ea) of this catalytic reaction when using 0.96 nm Cu hydrosol as a catalyst was calculated to be 9.37 kJ mol-1, which is considered an extremely low potential barrier. In addition, the synthesized nano Cu hydrosols showed size-dependent antibacterial activities against Pseudomonas aeruginosa (P. aeruginosa) and the minimal inhibitory concentration of the optimal sample was lower than 5.82 μg L-1.Highly stable monodispersed nano Cu hydrosols were facilely prepared by an aqueous chemical reduction method through selecting copper hydroxide (Cu(OH)2) as the copper precursor, poly(acrylic acid) (PAA) and ethanol amine (EA) as the complexing agents, and hydrazine hydrate as the reducing agent. The size of the

  3. Antibacterial activity of selected glass ionomer cements

    Directory of Open Access Journals (Sweden)

    Elżbieta Łuczaj-Cepowicz

    2014-01-01

    Full Text Available Introduction: The aim of the paper was to determine the antibacterial activity of four glass ionomer cements against bacteria of the genera Streptococcus and Lactobacillus.Material and methods: Four capsulated glass ionomer cements were applied in the study: Fuji Triage (GC, Fuji IX (GC, Ketac Molar (3M Espe and Ketac Silver (3M Espe. Four standard bacterial strains were used to assess the antibacterial activity of the studied cements: Streptococcus mutans, S. sanguis, S. salivarius and Lactobacillus casei. The antibacterial activity was determined by the agar diffusion method. The bacterial suspension was spread with a cotton swab on TSA plates. For each material six wells (7 mm diameter, 5 mm deep were made with a cork borer. Each well was then filled with freshly prepared cements. The results were obtained by measuring the bacterial growth inhibition zone after 1, 2, 3 and 7 days. Results: Fuji Triage cement inhibited the growth of all bacterial strains. Fuji IX cement demonstrated the most potent antibacterial activity against S. sanguis. Ketac Molar showed antibacterial activity against S. sanguis and S. salivarius, whereas Ketac Silver was efficient against S. mutans as well. Neither of the Ketac cements inhibited growth of the standard L. casei strain. Discussion: Antibacterial activity of glass ionomer cements has attracted the interest of scientists in recent years. Most authors, including us, carried out experiments using the agar diffusion method and demonstrated antibacterial activity of glass ionomer cements. Different antibacterial activity of glass ionomer cements, observed in our study and studies of other authors, depended on the evaluated cement, bacterial strain and period of evaluation.

  4. Antibacterial activity of selected glass ionomer cements.

    Science.gov (United States)

    Luczaj-Cepowicz, Elżbieta; Marczuk-Kolada, Grażyna; Zalewska, Anna; Pawińska, Małgorzata; Leszczyńska, Katarzyna

    2014-01-22

    The aim of the paper was to determine the antibacterial activity of four glass ionomer cements against bacteria of the genera Streptococcus and Lactobacillus. Four capsulated glass ionomer cements were applied in the study: Fuji Triage (GC), Fuji IX (GC), Ketac Molar (3M Espe) and Ketac Silver (3M Espe). Four standard bacterial strains were used to assess the antibacterial activity of the studied cements: Streptococcus mutans, S. sanguis, S. salivarius and Lactobacillus casei. The antibacterial activity was determined by the agar diffusion method. The bacterial suspension was spread with a cotton swab on TSA plates. For each material six wells (7 mm diameter, 5 mm deep) were made with a cork borer. Each well was then filled with freshly prepared cements. The results were obtained by measuring the bacterial growth inhibition zone after 1, 2, 3 and 7 days. Fuji Triage cement inhibited the growth of all bacterial strains. Fuji IX cement demonstrated the most potent antibacterial activity against S. sanguis. Ketac Molar showed antibacterial activity against S. sanguis and S. salivarius, whereas Ketac Silver was efficient against S. mutans as well. Neither of the Ketac cements inhibited growth of the standard L. casei strain. Antibacterial activity of glass ionomer cements has attracted the interest of scientists in recent years. Most authors, including us, carried out experiments using the agar diffusion method and demonstrated antibacterial activity of glass ionomer cements. Different antibacterial activity of glass ionomer cements, observed in our study and studies of other authors, depended on the evaluated cement, bacterial strain and period of evaluation.

  5. Antibacterial activity of heavy metal-loaded natural zeolite.

    Science.gov (United States)

    Hrenovic, Jasna; Milenkovic, Jelena; Ivankovic, Tomislav; Rajic, Nevenka

    2012-01-30

    The antibacterial activity of natural zeolitized tuffs containing 2.60wt.% Cu(2+), 1.47 Zn(2+) or 0.52 Ni(2+) were tested. Antibacterial activities of the zeolites against Escherichia coli and Staphylococcus aureus were tested after 1h and 24h of exposure to 1g of the zeolite in 100mL of three different media, namely Luria Bertani, synthetic wastewater and secondary effluent wastewater. The antibacterial activities of the zeolites in Luria Bertani medium were significantly lower than those in the other media and negatively correlated with the chemical oxygen demand of the media. The Ni-loaded zeolite showed high leaching of Ni(2+) (3.44-9.13wt.% of the Ni(2+) loaded) and weak antibacterial activity in the effluent water. Since Cu-loaded zeolite did not leach Cu(2+) and the leaching of Zn(2+) from Zn-loaded zeolite was low (1.07-1.61wt.% of the Zn(2+) loaded), the strong antibacterial activity classified the Cu- and Zn-loaded zeolite as promising antibacterial materials for disinfection of secondary effluent water.

  6. HIGHLY MICROBIAL RESISTANT GRAPHEME OXIDE NANOPARTICLES: SYNTHESIS, CHARACTERIZATION AND ITS ANTIBACTERIAL ACTIVITY

    Directory of Open Access Journals (Sweden)

    Vijaylaxmee Mishra

    2014-09-01

    Full Text Available The present work deigned to prepare graphene oxide nanoparticles and their antimicrobial activity has been evaluated. Graphene oxide is a singal layer of carbon arranged in a hexagonal pattern the basal planes and the edges of graphene oxide nanoparticles contain functional exogenous groups such as hydroxyl, carbonyl and epoxy group, which not only expand the interlayer distance but also make the atomic thick layer hydrophilic. Most important application in area related to transparent conductive film, composite materials, solar energy and biomedical application. Present work based on Hummer’s method which is most common used for preparing graphene oxide. The result graphene oxide was characterized by UV-Vis Spectra and SEM. The graphene oxide nanoparticles absorption peak was occurred at 289nm in UV-Vis spectra. SEM analysis showed the average particles size of 50-60nm corresponding to Hummer’s method respectively. Its antbacterial activity tested against gram negative and gram positive bacterial (Bacillus subtilis, Enterobacter aerogenes, and Staphylococcus epidermis strain. Graphene oxide nanoparticles of Hummer’s method showed the best inhibitory effect against Staphylococcus epidermis in comparison to other bacterial strain.

  7. Tunable, antibacterial activity of silicone polyether surfactants.

    Science.gov (United States)

    Khan, Madiha F; Zepeda-Velazquez, Laura; Brook, Michael A

    2015-08-01

    Silicone surfactants are used in a variety of applications, however, limited data is available on the relationship between surfactant structure and biological activity. A series of seven nonionic, silicone polyether surfactants with known structures was tested for in vitro antibacterial activity against Escherichia coli BL21. The compounds varied in their hydrophobic head, comprised of branched silicone structures with 3-10 siloxane linkages and, in two cases, phenyl substitution, and hydrophilic tail of 8-44 poly(ethylene glycol) units. The surfactants were tested at three concentrations: below, at, and above their Critical Micelle Concentrations (CMC) against 5 concentrations of E. coli BL21 in a three-step assay comprised of a 14-24h turbidometric screen, a live-dead stain and viable colony counts. The bacterial concentration had little effect on antibacterial activity. For most of the surfactants, antibacterial activity was higher at concentrations above the CMC. Surfactants with smaller silicone head groups had as much as 4 times the bioactivity of surfactants with larger groups, with the smallest hydrophobe exhibiting potency equivalent to sodium dodecyl sulfate (SDS). Smaller PEG chains were similarly associated with higher potency. These data link lower micelle stability and enhanced permeability of smaller silicone head groups to antibacterial activity. The results demonstrate that simple manipulation of nonionic silicone polyether structure leads to significant changes in antibacterial activity.

  8. Antibacterial activity of eight Brazilian annonaceae plants.

    Science.gov (United States)

    Takahashi, Jacqueline A; Pereira, Cássia R; Pimenta, Lúcia P S; Boaventura, Maria Amélia D; Silva, Luiz G F E

    2006-01-01

    Sixteen extracts, obtained from eight Brazilian plants of Annonaceae family, were screened for their antibacterial activity: Xylopia frutescens, X. aromatica, X. amazonica, X. benthamii, Annona ambotay, A. crassiflora, A. muricata and A. cherimolia. Amongst the investigated extracts, six showed antibacterial activity against at least one of the tested organisms at the concentration of 100 microg/mL. The most active extracts were those prepared from X. frutescens, X. amazonica, and A. ambotay. A phytochemical screening showed the presence of anonaceus acetogenins in some active extracts. Eleven diterpenoids were also tested for comparison purposes. Six were natural products, previously isolated from Xylopia sp. (kaurenoic, frutoic, xylopic, 15beta-hydroxy-kaurenoic and trachylobanic acids plus kaurenol) and five were derivatives of such compounds, obtained by esterification or reduction reactions. Trachylobanic acid showed antibacterial activity against B. subtilis and S. aureus.

  9. ANTIBACTERIAL ACTIVITY OF LOCAL MALAYSIAN HONEY

    Directory of Open Access Journals (Sweden)

    NURIZA TUMIN

    2005-01-01

    Full Text Available The antibacterial activity of five different local honey brands viz. Tualang, Hutan, Gelang, Pucuk Daun and Ee Feng Gu honey obtained from different locations in Malaysia was investigated. Honeys were tested for putative antibacterial activity by disc diffusion assay and their inhibition of growth of six pathogenic bacteria in batch culture. Minimum inhibitory concentration (MIC was determined for each of the honey tested using standard assay procedures. In terms of physicochemical properties, it was observed that the pH of these honeys was within 3.55–4.91, their specific gravity was 1.3–1.35, moisture content was 16–23.3% and dry matter content was 76.6–84%. Marked variations were observed in the antibacterial activity of these honey samples. Two honey brands, Hutan and Gelang did not produce any substantial antibacterial activity while other brands showed a spectrum of antibacterial activity with their growth inhibitory effect against at least three-four different bacterial species including S. typhi, S. aureus, S. sonnie and E. coli.

  10. Antibacterial activity of graphene layers

    Science.gov (United States)

    Dybowska-Sarapuk, Ł.; Kotela, A.; Krzemiński, J.; Janczak, D.; Wróblewska, M.; Marchel, H.; Łegorz, P.; Jakubowska, M.

    2016-09-01

    The bacterial biofilm is a direct cause of complications in management of various medical conditions. There is an ongoing search for a feasible method to prevent its growth, as an alternative to antibiotics, which are ineffective. The aim of the study was to prepare and evaluate a detailed algorithm for production of graphene coatings, using economically efficient methods of printed electronics (such as ink-jet printing or spray coating), and assess their antibacterial properties. Based on the preliminary results of our work we suggest that graphene coating may inhibit the formation of microbial biofilms. Further research is needed to verify antibacterial properties of graphene coatings and its future applications in prevention of biofilm-related infections, e.g. by coating surgical instruments, catheters or tracheostomy tubes. In addition, we propose a series of hypotheses to be evaluated in further work.

  11. THE ANTIFUNGAL AND ANTIBACTERIAL ACTIVITY OF TWO PLANTS FROM ASTEMCEAE

    OpenAIRE

    2015-01-01

    In this study, we have found that, Chlysanthemum coronarium has shownantifungal and antibacterial activity, but Inula viscosa didn't show any antifungalor antibacterial activity.Key words: Chrysanthemum coronarium; Inula viscosa; antifungal andantibacterial activities.

  12. Antibacterial activity of Pulicaria dysenterica extracts.

    Science.gov (United States)

    Nickavar, Bahman; Mojab, Faraz

    2003-06-01

    Aqueous, methanolic and chloroformic extracts of Pulicaria dysenterica aerial parts were tested for their antibacterial activity using the disc-diffusion assay technique. The methanolic extract was found to be the most effective extract against three out of six tested bacteria. All of the extracts were active against Vibrio cholera.

  13. Antibacterial Activity of Punica granatum Linn.

    Directory of Open Access Journals (Sweden)

    Kenan Tunç

    2013-08-01

    Full Text Available In this study, it was investigated that the extracts (ethanol, aceton, methanol, ethyl acetat obtained from fruit peels of the plant to whether has antibacterial effect against Streptococcus mitis CNCTC 4/77, Streptococcus salivarius CNCTC 64/59, Streptococcus mutans CNCTC 8/77, Staphylococcus epidermidis ATCC 12228, Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, Salmonella abony NCTC 6017, Salmonella typhimurium ATCC 14028, Enterococcus faecalis ATCC 29212, Bacillus subtilis ATCC 6633 bacteria strains in vitro. The antibacterial activity of extracts was evaluated according to disc diffusion method. It has been determined that pomegranate peel's extract had the highest inhibition zone diameters ( 18-30 mm against S. epidermidis and S. aureus bacteria strains. The antibacterial activity of plant against Streptococcus mitis is determined in this study for the first time.

  14. Synthesis and Antibacterial Activities of Selenide Derivatives of Benzisoselenazolone

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A series of Benzisolselenazolone (BISA) derivatives were synthesized and evaluated for their antibacterial activities against E coli. by using LKB-2277 bioactivity monitor. Other bioactivities were tested by the method of High Throughput Screening for pharmaceutical activity compounds (HTP) BISA derivatives 3b,at the concentration of 40 μg/mL, showed 100% antibacterial activity and 62% inhibition rate of aldose reductase(at the concentration of 5μg/mL). These new compound structures have determined by IR, 1H NM Rand MS spectra.

  15. Antibacterial activity of selected Egyptian ethnomedicinal plants

    Directory of Open Access Journals (Sweden)

    Mashait, M.

    2013-01-01

    Full Text Available Aims: Medicinal plants have recently received the attention of the antimicrobial activity of plants and their metabolites due to the challenge of growing incidences of drug-resistant pathogens. The aims of this study were to determine the antibacterial activities of plant extracts used as ethnomedicinal in Egypt. Methodology and Results: Investigations were carried out to assess the antibacterial efficiency of 11 plant extracts used as ethnopharmacological among Egyptian native people against infectious diseases. Crude methanol, ethanol,chloroform, hexane, acetone and aqueous extract of plants were tested for antibacterial activity in vitro against ten bacterial isolates using the disc diffusion method test. Discs were impregnated with 2 mg/mL of different solvent extracts. Among all the crude extracts, the methanol extract showed the highest activity than other extracts. P. harmala and S. officinalis exhibited highest antibacterial activity against gram positive and negative bacteria while the remainingplants extracts showed less activity. All the plant extracts showed no significant effect against the Bordetella bronchisepta ATCC 4617 except the extracts of M. fragrans and L. sativum. E. coli is the most sensitive microorganism tested, with the lowest MIC value (0.5 mg/mL in the presence of the plant extract of P. harmala and S. officinalis.Conclusion, significance and impact of study: Results obtained herein, may suggest that the ethnomedicinal Egyptian plants possess antimicrobial activity and therefore, they can be used in biotechnological fields as natural preservative ingredients in food and/or pharmaceutical industry.

  16. Synthesis and Antibacterial Activity of Novel Quaternary Ammonium Pyridoxine Derivatives.

    Science.gov (United States)

    Shtyrlin, Nikita V; Sapozhnikov, Sergey V; Koshkin, Sergey A; Iksanova, Alfiya G; Sabirov, Arthur H; Kayumov, Airat R; Nureeva, Aliya A; Zeldi, Marina I; Shtyrlin, Yurii G

    2015-01-01

    A series of 26 quaternary ammonium pyridoxine derivatives were synthesized and their cytotoxicity and antibacterial activities against clinically relevant bacterial strains were tested in vitro. The antibacterial activity of mono-ammonium salts increased with the rise of the lipophilicity and compound 3,3,5-trimethyl-8,8-dioctyl-1,7,8,9-tetrahydro-[1,3]dioxino[5,4-d]pyrrolo[3,4-b]pyridin-8-ium chloride (2d) reaches a maximum among them. Bis-ammonium salt of pyridoxine 4 with two dimethyloctylamine groups also demonstrated high antibacterial activity despite lower lipophilicity. The results of MTT assay indicated that HEK 293 cells were more sensitive than HSF to quaternary ammonium pyridoxine derivatives. Compounds 2d and 4 did not induce the damage of the DNA and might be of interest in the development of new antimicrobials.

  17. Chemical analyses, antibacterial activity and genetic diversity ...

    African Journals Online (AJOL)

    SAM

    2014-06-25

    Jun 25, 2014 ... Key words: Citrus, genetic diversity, ISSR markers, chemical analyses, antibacterial. ... ment of DNA based marker systems has advanced our ... Total acidity of the juices was determined by titration method as ... Greek compressed C. sinensis. 37 163 ..... flavonoids have a large spectrum of biological activity.

  18. Antibacterial activity of Ailanthus excelsa (Roxb).

    Science.gov (United States)

    Shrimali, M; Jain, D C; Darokar, M P; Sharma, R P

    2001-03-01

    The antibacterial activity of different fractions of a methanol extract obtained from the dried stem bark of Ailanthus excelsa (Roxb) was studied using different bacterial strains. The ethyl acetate fraction inhibited the growth of all test bacteria. The MIC of the EA fraction was found to be 6 mg/disc. Copyright -Copyright 2001 John Wiley & Sons, Ltd.

  19. ANTIBACTERIAL ACTIVITY OF Tridax procumbens Linn

    Directory of Open Access Journals (Sweden)

    V.Bharathi

    2012-04-01

    Full Text Available Tridax procumbens Linn belongs to the family Compositae. The extracts of Tridax procumbens have been reported to have various pharmacological effects like mosquito repellant activity, leishmanicidal, hepatoprotective effect on liver antioxidant system, immunomodulatory effect, wound healing activity and antiprotozoal effects.The methanolic and ethyl acetate extracts of Tridax procumbens were used for this study. The antibacterial activity of methanolic and ethyl acetate leaf extracts of Tridax procumbens Linn (L. were examined against Escherichia coli,,Klebsiella pneumoniae,Salmonella typhi, Bacillus cereus and Staphylococcus aureus. Antibacterial activity was investigated by disc and agarwell diffusion method. The ethyl acetate extracts of the Tridax procumbens showed effective inhibition against the Staphylococcus aureus thancompared to other organism. Therefore the leaves of Tridax procumbens can be considered to be the promising source of antimicrobial compounds.

  20. MgO nanoparticles as antibacterial agent: preparation and activity

    OpenAIRE

    Zhen-Xing Tang; Bin-Feng Lv

    2014-01-01

    Bacterial pollution is a great risk for human health. Nanotechnology offers a way to develop new inorganic antibacterial agents. Nano-inorganic metal oxide has a potential to reduce bacterial contamination. MgO is an important inorganic oxide and has been widely used in many fields. Many studies have shown that MgO nanoparticles have good antibacterial activity. Therefore, in this paper, the main synthesis methods, antibacterial activity and antibacterial mechanisms of MgO nanoparticles are r...

  1. MgO nanoparticles as antibacterial agent: preparation and activity

    OpenAIRE

    Zhen-Xing Tang; Bin-Feng Lv

    2014-01-01

    Bacterial pollution is a great risk for human health. Nanotechnology offers a way to develop new inorganic antibacterial agents. Nano-inorganic metal oxide has a potential to reduce bacterial contamination. MgO is an important inorganic oxide and has been widely used in many fields. Many studies have shown that MgO nanoparticles have good antibacterial activity. Therefore, in this paper, the main synthesis methods, antibacterial activity and antibacterial mechanisms of MgO nanoparticles are r...

  2. MgO nanoparticles as antibacterial agent: preparation and activity

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Zhen-Xing, E-mail: tangzhenxing@126.com [Department of Food Science, Anqing, Vocational and Technical College, Anqing, Anhui (China); Lv, Bin-Feng [Date Palm Research Center, King Faisal University, (Saudi Arabia)

    2014-07-15

    Bacterial pollution is a great risk for human health. Nanotechnology offers a way to develop new inorganic antibacterial agents. Nano-inorganic metal oxide has a potential to reduce bacterial contamination. MgO is an important inorganic oxide and has been widely used in many fields. Many studies have shown that MgO nanoparticles have good antibacterial activity. Therefore, in this paper, the main synthesis methods, antibacterial activity and antibacterial mechanisms of MgO nanoparticles are reviewed. (author)

  3. Induction, selection and antibacterial activity of the antibacterial peptides from lepldopteran insect cultured cell lines

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We induced 3 cell lines that were in vitro cultured from Lepidoptera with heat inactivated Escherichia coil DH5α to stimulate the antibacterial peptide followed by antibacterial activity assay,induction dynamic research and Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Tricine SDS-PAGE) experiment.The antibacterial activity of the induced BTI-Tn-5B1 cell line was the highest,and the antibacterial activity increased gradually to the highest level in 16 hours after stimulation.A new antibacterial peptide with a molecular weight of about 8000 Da was preferentially induced in Trichoplusia ni BTI-Tn-5B1 ceils in 16 hours after stimulation.Antibacterial activity assays indicated that it had inhibition against Staphylococcus aureus,Escherichia coli K12D31 and Salmonella derby.It has especially strong inhibition against Gram-negative bacteria such as Escherichia coli KI2D31 and Salmonella derby.

  4. Metal Fe{sup 3+} ions assisted synthesis of highly monodisperse Ag/SiO{sub 2} nanohybrids and their antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Nianchun; Xue, Feng [College of Material Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Yu, Xiang [Analytical and Testing Center, Jinan University, Guangzhou 510632 (China); Zhou, Huihua [Guangdong East Sunshine Pharmaceutical Co., Ltd., Dongguan 523871 (China); Ding, Enyong, E-mail: eyding@scut.edu.cn [College of Material Science and Engineering, South China University of Technology, Guangzhou 510641 (China)

    2013-02-15

    Graphical abstract: TEM images of the Ag/SiO{sub 2}-2 nanohybrids. The homogeneous and more mono-disperse Ag nanoparticles deposit on SiO{sub 2} spheres. Through this method, Ag nanoparticles are easily formed on the surface of SiO{sub 2} compared to other methods. Highlights: Black-Right-Pointing-Pointer We prepared homogeneous and mono-dispersed Ag/SiO{sub 2}-2 nanohybrids by adding Fe{sup 3+} ions. Black-Right-Pointing-Pointer The Ag/SiO{sub 2}-2 nanohybrids had core(SiO{sub 2})-shell(Ag) structure. Black-Right-Pointing-Pointer The Ag/SiO{sub 2}-2 nanohybrids exhibited excellent antibacterial activity against bacteria. Black-Right-Pointing-Pointer The reaction temperature was lower and the yield of Ag/SiO{sub 2}-2 nanohybrids were higher. - Abstract: Highly monodispersed Ag/SiO{sub 2} nanohybrids with excellent antibacterial property were synthesized by using DMF as a reducing agent and employing an additional redox potential of metal Fe{sup 3+} ion as a catalytic agent. The obtained Ag/SiO{sub 2}-2 nanohybrids of about 240 nm were highly monodispersity and uniformity by adding trace Fe{sup 3+} ions into the reaction which Ag{sup +} reacted with N,N-dimethyl formamide (DMF) at 70 Degree-Sign C. Compared to the conventional techniques, which need long time and high temperature for silica coating of Ag nanoparticles, this new method was capable of synthesizing monodispersed, uniform, high yield Ag/SiO{sub 2} nanohybrids. The electron was transferred from the Fe{sup 2+} ion to the Ag{sup +} ion to accelerate the nucleation of silver nanoparticles. The chemical structures, morphologies and properties of the Ag/SiO{sub 2} nanohybrids were characterized by X-ray diffraction (XRD), (High-resolution, Scanning transmission) transmission electron microscopy (TEM, HRTEM and STEM), and X-ray photoelectron spectroscopy (XPS), and UV-vis spectroscopy (UV-vis) and test of antibacterial. The results demonstrated that the silver nanoparticles supported on the surface of Si

  5. [Antibacterial activity of natural compounds - essential oils].

    Science.gov (United States)

    Hassan, Sherif T S; Majerová, Michaela; Šudomová, Miroslava; Berchová, Kateřina

    2015-12-01

    Since the problem of bacterial resistance has become a serious problem worldwide, it was necessary to search for new active substances that can overcome the problem and enhance the treatment efficacy of bacterial infections. Numerous plant-derived essential oils exhibited significant antibacterial activities. This review aimed to summarize the most promising essential oils that exhibited remarkable antibacterial activities against various bacterial infections, including staphylococcal infections, Helicobacter pylori infections, skin infections, tuberculosis infection and dental bacterial infection. The synergy effect of essential oils in combination with antibiotics, as well as their role in the treatment of bacterial infections have been discussed. Essential oils can be used as models for further studies in vivo and clinical trials.

  6. Antibacterial activity of Lawsonia inermis Linn (Henna) against Pseudomonas aeruginosa

    Institute of Scientific and Technical Information of China (English)

    Habbal O; Hasson SS; El-Hag AH; Al-Mahrooqi Z; Al-Hashmi N; Al-Bimani Z; MS Al-Balushi; Al-Jabri AA

    2011-01-01

    Objective: To investigate the antibacterial activity of henna (Lawsonia inermis Linn) obtained from different regions of Oman against a wide array of micro-organisms. Methods: Fresh henna samples were obtained from different regions of Oman as leaves and seeds. 100 g fresh and dry leaves and 50 g of fresh and dry seeds were separately soaked in 500 mL of ethanol for three days, respectively, with frequent agitation. The mixture was filtered, and the crude extract was collected. The crude extract was then heated, at 48 ℃ in a water bath to evaporate its liquid content. The dry crude henna extract was then tested for its antibacterial activity using well-diffusion antibiotic susceptibility technique. Henna extracts were investigated for their antibacterial activity at different concentrations against a wide array of different micro-organisms including a laboratory standard bacterial strain of Pseudomonas aeruginosa (NCTC 10662) (P. aeruginosa) and eleven fresh clinical isolates of P. aeruginosa obtained from patients attending the Sultan Qaboos University Hospital (SQUH). 2-Hydroxy-p-Nathoqinone-Tech (2-HPNT, MW=174.16, C10H6O3) was included as control (at 50% concentration) along with the henna samples tested. Results: Henna samples demonstrated antibacterial activity against all isolates but the highest susceptibility was against P. aeruginosa with henna samples obtained from Al-sharqyia region. Conclusions: Omani henna from Al-sharqyia region demonstrates high in vitro anti-P. aeruginosa activity compared with many henna samples from different regions of Oman.

  7. Honey:its medicinal property and antibacterial activity

    Institute of Scientific and Technical Information of China (English)

    Manisha Deb Mandal; Shyamapada Mandal

    2011-01-01

    Indeed, medicinal importance of honey has been documented in the world's oldest medical literatures, and since the ancient times, it has been known to possess antimicrobial property as well as wound-healing activity. The healing property of honey is due to the fact that it offers antibacterial activity, maintains a moist wound condition, and its high viscosity helps to provide a protective barrier to prevent infection. Its immunomodulatory property is relevant to wound repair too. The antimicrobial activity in most honeys is due to the enzymatic production of hydrogen peroxide. However, another kind of honey, called non-peroxide honey (viz., manuka honey), displays significant antibacterial effects even when the hydrogen peroxide activity is blocked. Its mechanism may be related to the low pH level of honey and its high sugar content (high osmolarity) that is enough to hinder the growth of microbes. The medical grade honeys have potentin vitrobactericidal activity against antibiotic-resistant bacteria causing several life-threatening infections to humans. But, there is a large variation in the antimicrobial activity of some natural honeys, which is due to spatial and temporal variation in sources of nectar. Thus, identification and characterization of the active principle(s) may provide valuable information on the quality and possible therapeutic potential of honeys (against several health disorders of humans), and hence we discussed the medicinal property of honeys with emphasis on their antibacterial activities.

  8. EVALUATION OF ANTIBACTERIAL ACTIVITY OF CAFFEINE

    Directory of Open Access Journals (Sweden)

    Pawar Pruthviraj

    2011-04-01

    Full Text Available The present study was carried out with water soluble portion and pure solvent of the acetone, ethanol, methanol, acetonitrile, water extracts of leaves and leaf buds of Camellia sinensis (green tea, and beans of Coffea arabica (coffee. Caffeine (3,7-dihydro-1, 3,7-trimethyl-1H-purine-2,6-dione was isolated from both plants using a liquid-liquid extraction method, detected on thin layer chromatography (TLC plates in comparison with standard caffeine, which served as a positive control. After performing the gross behavioral study, the Antibacterial activity was evaluated against Gram-negative bacteria included; Escherichia coli, Proteus mirabilis, Klebsiella pneumonia and Pseudomonas aeruginosa Both compounds at a concentration of 2 mg/ml showed similar antibacterial activities against all tested bacteria, except for P. mirabilis, and the highest inhibitory effect was observed against P. aeruginosa using a modified agar diffusion method. The minimal inhibitory concentration (MIC of caffeine was determined using a broth microdilution method in 96 multi-well microtitre plates. MIC values ranged from 65.5 to 250.0 µg/ml for the caffeine isolated from coffee and 65.5 to 500.0 µg/ml for green tea caffeine. Combination results showed additive effects against most pathogenic bacteria especially for P. aeruginosa, using both antibacterial assays.

  9. Light-activated polymethylmethacrylate nanofibers with antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Elashnikov, Roman [Department of Solid State Engineering, University of Chemistry and Technology, 16628 Prague (Czech Republic); Lyutakov, Oleksiy, E-mail: lyutakoo@vscht.cz [Department of Solid State Engineering, University of Chemistry and Technology, 16628 Prague (Czech Republic); Ulbrich, Pavel [Department of Biochemistry and Microbiology, University of Chemistry and Technology, 16628 Prague (Czech Republic); Svorcik, Vaclav [Department of Solid State Engineering, University of Chemistry and Technology, 16628 Prague (Czech Republic)

    2016-07-01

    The creation of an antibacterial material with triggerable properties enables us to avoid the overuse or misuse of antibacterial substances and, thus, prevent the emergence of resistant bacterial strains. As a potential light-activated antibacterial material, polymethylmethacrylate (PMMA) nanofibers doped with silver nanoparticles (AgNPs) and meso-tetraphenylporphyrin (TPP) were prepared by electrospinning. TPP was chosen as an effectively reactive oxygen species (ROS) producer. Antibacterial tests on Staphylococcus epidermidis (S. epidermidis) and Enterococcus faecalis (E. faecalis) showed the excellent light-triggerable antibacterial activity of the doped materials. Upon light irradiation at the wavelength corresponding to the TPP absorption peak (405 nm), antibacterial activity dramatically increased, mostly due to the release of AgNPs from the polymer matrix. Furthermore, under prolonged light irradiation, the AgNPs/TPP/PMMA nanofibers, displayed enhanced longevity and photothermal stability. Thus, our results suggest that the proposed material is a promising option for the photodynamic inactivation of bacteria. - Highlights: • The novelty of proposed work can be summared as follow: • Silver nanoparticles/meso-tetraphenylporphyrin embedded polymethylmethacrylate nanofibers were obtained for the first time. • Light triggering of PMMA fibers leads to sufficient release of AgNPs or their agglomeration, depending on the light source. • Release of AgNPs leads to appearance of pronounced antimicrobial activity, which can be switched on/off by the illumination.

  10. Investigation of the antibacterial activity of pioglitazone

    Directory of Open Access Journals (Sweden)

    Alzoubi KH

    2011-09-01

    Full Text Available Majed M Masadeh1, Nizar M Mhaidat2, Sayer I Al-Azzam2, Karem H Alzoubi21Department of Pharmaceutical Technology; 2Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, JordanPurpose: To evaluate the antibacterial potential of pioglitazone, a member of the thiazolidinediones class of drugs, against Gram-positive (Streptococcus pneumoniae and Gram-negative (Escherichia coli and Klebsiella pneumoniae bacteria.Methods: Susceptibility testing was done using the antibiotic disk diffusion method and the minimal inhibitory concentration (MIC of pioglitazone was measured according to the broth micro incubation standard method.Results: Pioglitazone induced a dose-dependent antibacterial activity in which the optimal concentration was 80 µM. Furthermore, results indicated that while E. coli was sensitive (MIC = 31.25 ± 3.87 mg/L to pioglitazone-induced cytotoxicity, S. pneumoniae and K. pneumoniae were resistant (MIC = 62.5 ± 3.77 mg/L and MIC = 62.5 ± 4.14 mg/L, respectively. Moreover, pretreatment of bacteria with a suboptimal concentration of pioglitazone (40 µM before adding amoxicillin, cephalexin, co-trimoxazole, or ciprofloxacin enhanced the antibacterial activity of all agents except co-trimoxazole. This enhancing effect was particularly seen against K. pneumoniae.Conclusion: These results indicate the possibility of a new and potentially important pioglitazone effect and the authors’ ongoing studies aim to illustrate the mechanism(s by which this antibacterial effect is induced.Keywords: pioglitazone, susceptibility testing, antibiotics, diabetes 

  11. Antibacterial activity of novel benzopolycyclic amines.

    Science.gov (United States)

    Barniol-Xicota, Marta; Escandell, Alex; Valverde, Elena; Julián, Esther; Torrents, Eduard; Vázquez, Santiago

    2015-01-15

    Staphylococcus aureus, especially strains resistant to multiple antibiotics, is a major pathogen for humans and animals. In this paper we have synthesized and evaluated the antibacterial activity of a new series of benzopolycyclic amines. Some of them exhibited μM MIC values against Staphylococcus aureus and other bacteria, including methicillin-resistant S. aureus MRSA. Compound 8 that displayed a good selectivity index, showed to be active in eliminating bacterial cells forming a preexisting biofilm. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. In Vitro Antibacterial Activity of Essential Oils against Streptococcus pyogenes

    OpenAIRE

    Julien Sfeir; Corinne Lefrançois; Dominique Baudoux; Séverine Derbré; Patricia Licznar

    2013-01-01

    Streptococcus pyogenes plays an important role in the pathogenesis of tonsillitis. The present study was conducted to evaluate the in vitro antibacterial activities of 18 essential oils chemotypes from aromatic medicinal plants against S. pyogenes. Antibacterial activity of essential oils was investigated using disc diffusion method. Minimum Inhibitory Concentration of essential oils showing an important antibacterial activity was measured using broth dilution method. Out of 18 essential oils...

  13. An intravenous clarithromycin lipid emulsion with a high drug loading, H-bonding and a hydrogen-bonded ion pair complex exhibiting excellent antibacterial activity

    Directory of Open Access Journals (Sweden)

    Haoyu Gong

    2016-10-01

    Full Text Available The aim of this study was to develop an intravenous clarithromycin lipid emulsion (CLE with good stability and excellent antibacterial activity. The CLE was prepared by the thin-film dispersed homogenization method. The interaction between clarithromycin (CLA and cholesteryl hemisuccinate (CHEMS was confirmed by DSC, FT-IR and 1H NMR analysis. The interfacial drug loading, thermal sterilization, freeze–thaw stability, and in vitro and in vivo antibacterial activity were investigated systematically. DSC, FT-IR and 1H NMR spectra showed that CHEMS (CLA: CHEMS, M ratio 1:2 could interact with CLA through H-bonding and a hydrogen-bonded ion pair. The CHEMS was found necessary to maintain the stability of CLE. Ultracentrifugation showed that almost 88% CLA could be loaded into the interfacial layer. The optimized CLE formulation could withstand autoclaving at 121 °C for 10 min and remain stable after three freeze–thaw cycles. The in vitro susceptibility test revealed that the CLA–CHEMS ion-pair and CLE have similar activity to the parent drug against many different bacterial strains. The in vivo antibacterial activity showed that the ED50 of intravenous CLE was markedly lower than that of CLA solution administrated orally. CLE exhibited pronounced antibacterial activity and might be a candidate for a new nanocarrier for CLA with potential advantages over the current commercial formulation.

  14. Synthesis and Antibacterial Activity of Thiophenes

    Directory of Open Access Journals (Sweden)

    Wedad M. Al-Adiwish

    2012-01-01

    Full Text Available 2-[Bis(methylthiomethylene]propanedinitrile 1a reacted in one-pot successively with piperidine, sodium sulfide, chloroacetonitrile, and potassium carbonate to afford 3-amino-5-(1-piperidinyl-2,4-thiophenedicarbonitrile 2a. Similar reaction using the last three reagents with ethyl 2-cyano-3,3-bis(methylthioacrylate 1b produced ethyl 4-amino-5-cyano-2-(methylthiothiophene-3-carboxylate 2b. The synthesized compounds were characterized by using FT-IR, 1H-NMR, 13C-NMR, and mass spectral data. Antibacterial activities of the synthesized compounds are also reported.

  15. High Selective Performance of Designed Antibacterial and Anticancer Peptide Amphiphiles.

    Science.gov (United States)

    Chen, Cuixia; Chen, Yucan; Yang, Cheng; Zeng, Ping; Xu, Hai; Pan, Fang; Lu, Jian Ren

    2015-08-12

    Short designed peptide amphiphiles are attractive at killing bacteria and inhibiting cancer cell growth, and the flexibility in their structural design offers a great potential for improving their potency and biocompatibility to mammalian host cells. Amino acid sequences such as G(IIKK)nI-NH2 (n≥3) have been shown to be membrane lytic, but terminal amino acid modifications could impose a huge influence on their performance. We report in this work how terminal amino acid modifications to G(IIKK)3I-NH2 influence its α-helical structure, membrane penetrating ability, and selective actions against different cell types. Deletion of an N-terminal Gly or a C-terminal Ile did not affect their antibacterial activity much, an observation consistent with their binding behavior to negatively charged membrane lipid monolayers. However, the cytotoxicity against mammalian cells was much worsened by the N-terminal Gly deletion, consistent with an increase in its helical content. Despite little impact on the antibacterial activity of G(IIKK)3I-NH2, deletion of both terminal amino acids greatly reduced its antitumor activity. Cholesterol present in tumor cell membrane-mimic was thought to constrain (IIKK)3-NH2 from penetrating into the cancerous membranes, evident from its lowest surface physical activity at penetrating model lipid membranes. On the other hand, its low toxicity to normal mammalian cells and high antibacterial activity in vitro and in vivo made it an attractive antibacterial agent. Thus, terminal modifications can help rebalance the different interactions involved and are highly effective at manipulating their selective membrane responses.

  16. Dual mode antibacterial activity of ion substituted calcium phosphate nanocarriers for bone infections

    Directory of Open Access Journals (Sweden)

    Sampath Kumar eT.S.

    2015-05-01

    Full Text Available Nanotechnology has tremendous potential for the management of infectious diseases caused by multi-drug resistant (MDR bacteria, through the development of newer antibacterial materials and efficient modes of antibiotic delivery. Calcium phosphate (CaP bioceramics are commonly used as bone substitutes due to their similarity to bone mineral and are widely researched upon for the treatment of bone infections associated with bone loss. CaPs can be used as local antibiotic delivery agents for bone infections and can be substituted with antibacterial ions in their crystal structure to have a wide spectrum, sustained antibacterial activity even against drug resistant bacteria. In the present work, a dual mode antibiotic delivery system with antibacterial ion substituted calcium deficient hydroxyapatite (CDHA nanoparticles has been developed. Antibacterial ions such as zinc, silver and strontium have been incorporated into CDHA at concentrations of 6 at. %, 0.25-0.75 at. % and 2.5-7.5 at. % respectively. The samples were found to be phase pure, acicular nanoparticles of length 40-50 nm and width 5-6 nm approximately. The loading and release profile of doxycycline, a commonly used antibiotic, was studied from the nanocarriers. The drug release was studied for five days and the release profile was influenced by the ion concentrations. The release of antibacterial ions was studied over a period of 21 days. The ion substituted CDHA samples were tested for antibacterial efficacy on S.aureus and E.coli by MIC/MBC studies and time-kill assay. AgCDHA and ZnCDHA showed high antibacterial activity against both bacteria while SrCDHA was weakly active against S.aureus. Present study shows that the antibiotic release can provide the initial high antibacterial activity and the sustained ion release can provide a long-term antibacterial activity. Such dual mode antibiotic and antibacterial ion release offers an efficient and potent way to treat an incumbent drug

  17. 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.

  18. Antibacterial activity of silver nanoparticles synthesized from serine

    Energy Technology Data Exchange (ETDEWEB)

    Jayaprakash, N. [Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034 (India); SRM Valliammai Engineering College, Department of Chemistry, Chennai 603 203 (India); Judith Vijaya, J., E-mail: jjvijayaloyola@yahoo.co.in [Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034 (India); John Kennedy, L. [Materials Division, School of Advanced Sciences, VIT University, Chennai Campus, Chennai 600 048 (India); Priadharsini, K.; Palani, P. [Department of Center for Advanced Study in Botany, University of Madras, Guindy Campus, Chennai 600 025 (India)

    2015-04-01

    Silver nanoparticles (Ag NPs) were synthesized by a simple microwave irradiation method using polyvinyl pyrrolidone (PVP) as a capping agent and serine as a reducing agent. UV–Visible spectra were used to confirm the formation of Ag NPs by observing the surface plasmon resonance (SPR) band at 443 nm. The emission spectrum of Ag NPs showed an emission band at 484 nm. In the presence of microwave radiation, serine acts as a reducing agent, which was confirmed by Fourier transformed infrared (FT-IR) spectrum. High-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning electron microscopy (HR-SEM) were used to investigate the morphology of the synthesized sample. These images showed the sphere-like morphology. The elemental composition of the sample was determined by the energy dispersive X-ray analysis (EDX). Selected area electron diffraction (SAED) was used to find the crystalline nature of the Ag NPs. The electrochemical behavior of the synthesized Ag NPs was analyzed by the cyclic voltammetry (CV). Antibacterial experiments showed that the prepared Ag NPs showed relatively similar antibacterial activities, when compared with AgNO{sub 3} against Gram-positive and Gram-negative bacteria. - Highlights: • Microwave irradiation method is used to synthesize silver nanoparticles. • Highly stable silver nanoparticles are produced from serine. • A detailed study of antibacterial activities is discussed. • Formation mechanism of silver microspheres has been proposed.

  19. Syntheses and Antibacterial Activities of Novel Erythromycin O-Alkylamidoximes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhan-tao; WU Cai-ling; ZHAO Yan-fang; CHENG Mao-sheng; GONG Ping

    2005-01-01

    Nine novel erythromycin O-alkylamidoxime derivatives were prepared in excellent yields via the condensation of different O-alkylhydroxylamines with erythromycin imino ether. The structures of all the compounds prepared were confirmed by 1H NMR, 13C NMR, IR and MS, and their in vtiro antibacterial activities were tested. Among the compounds, two of them showed good antibacterial activities.

  20. EVALUATION OF ANTIBACTERIAL ACTIVITY OF HERBS

    Directory of Open Access Journals (Sweden)

    Pesaramelli Karteek

    2012-08-01

    Full Text Available Medicinal plants have been used for centuries as remedies for human diseases because they contain components of therapeutic value. The acceptance of traditional medicine as an alternative form of health care and the development of microbial resistance to the available antibiotics has led researchers to investigate the antimicrobial activity of medicinal plants. Wild plants have been reported to have antimicrobial and antioxidant properties for centuries, and indigenous plants have been used in herbal medicine for curing various diseases. The development of bacterial resistance to currently available antibiotics has necessitated the search for new antibacterial agents. In lieu of the above justification, present study aimed at evaluating the In vitro antibacterial studies on the extracts of three herbs namely Punica Granatum, Ricinus communis and Zingiber officinalis carried out on five medically important bacterial strains (Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Proteus vulgaris. Based on the present investigation results, extracts has great potential against different microorganisms tested and has inhibitory effect. It can be concluded that these plants can be used as therapeutic natural agents that may serve as lead for the development of new pharmaceuticals addressing the major therapeutic needs.

  1. Antibacterial activity of silver nanoparticles with different morphologies as well as their possible antibacterial mechanism

    Science.gov (United States)

    Hu, Guansong; Jin, Wenxiu; Chen, Qingyuan; Cai, Yuchun; Zhu, Qiuhua; Zhang, Wanzhong

    2016-10-01

    Silver nanoparticles (AgNPs) have good antibacterial activity and their morphologies have important influence on their activity. The relationship between their bactericidal property and morphology has not been studied thoroughly. Silver triangular nanoplates have basic {111} surface, nanospheres and nanocubes mainly have {100} planes, and nanorods have {100} side surfaces and {111} end facets. It was said that {111} crystal plane of AgNPs may play a prime role in antibacterial progress. Moreover, the antibacterial activity of nanocubes is not very clear when compared to nanoparticles with other morphologies. In this paper, we studied the antibacterial activity of nanocubes and attempted to confirm whether nanoparticles with {111} crystal facet truly had stronger antibacterial activity than other nanoparticles. We prepared four kinds of AgNPs and found silver triangle nanoplates had the best antibacterial activity, while nanospheres, nanocubes and short nanorods showed similar efficacy. It may provide a reference for safe application of AgNPs with different morphologies in the medical field.

  2. In Vitro Antibacterial Activity of Essential Oils against Streptococcus pyogenes

    Directory of Open Access Journals (Sweden)

    Julien Sfeir

    2013-01-01

    Full Text Available Streptococcus pyogenes plays an important role in the pathogenesis of tonsillitis. The present study was conducted to evaluate the in vitro antibacterial activities of 18 essential oils chemotypes from aromatic medicinal plants against S. pyogenes. Antibacterial activity of essential oils was investigated using disc diffusion method. Minimum Inhibitory Concentration of essential oils showing an important antibacterial activity was measured using broth dilution method. Out of 18 essential oils tested, 14 showed antibacterial activity against S. pyogenes. Among them Cinnamomum verum, Cymbopogon citratus, Thymus vulgaris CT thymol, Origanum compactum, and Satureja montana essential oils exhibited significant antibacterial activity. The in vitro results reported here suggest that, for patients suffering from bacterial throat infections, if aromatherapy is used, these essential oils, considered as potential antimicrobial agents, should be preferred.

  3. Structure and antibacterial activity of new layered perovskite compounds

    Institute of Scientific and Technical Information of China (English)

    TAN Shao-zao; ZHANG Li-ling; XIA Liao-yuan; LIU Ying-liang; LI Du-xin

    2007-01-01

    New layered perovskite compounds, AgxNa2-xLa2Ti3O10 (x=0.2, 0.3 and 0.5) were synthesized by an ion-exchange reaction of Na2La2Ti3O10 with AgNO3 solution and characterized by energy dispersive X-ray analysis(EDX), X-ray diffractometry(XRD), scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS). The ion-exchange processes were optimized, and the antibacterial activity, light permanency and water-resistance were evaluated. Surprisedly, no significant changes in crystal structure of Na2La2Ti3O10 are found by the exchange of silver ions. The Ag0.3Na1.7La2Ti3O10 particles conglomerate obviously with irregular shape and size. Ag0.3Na1.7La2Ti3O10, possessing the minimum inhibitory concentrations(MICs) against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) of 180 mg/L and 240 mg/L, has high antibacterial activity, good light permanency and water-resistance. The ionic state silver in AgxNa2-xLa2Ti3O10 is the antibacterial active component.

  4. Antibacterial activity of Pseudonocardia sp. JB05, a rare salty soil actinomycete against Staphylococcus aureus.

    Science.gov (United States)

    Jafari, Nesa; Behroozi, Reza; Farajzadeh, Davoud; Farsi, Mohammad; Akbari-Noghabi, Kambiz

    2014-01-01

    Staphylococcus aureus is a Gram-positive bacterium that causes many harmful and life-threatening diseases. Some strains of this bacterium are resistant to available antibiotics. This study was designed to evaluate the ability of indigenous actinomycetes to produce antibacterial compounds against S. aureus and characterize the structure of the resultant antibacterial compounds. Therefore, a slightly modified agar well diffusion method was used to determine the antibacterial activity of actinomycete isolates against the test microorganisms. The bacterial extracts with antibacterial activity were fractionated by silica gel and G-25 sephadex column chromatography. Also, the active fractions were analyzed by thin layer chromatography. Finally, the partial structure of the resultant antibacterial compound was characterized by Fourier transform infrared spectroscopy. One of the isolates, which had a broad spectrum and high antibacterial activity, was designated as Pseudonocardia sp. JB05, based on the results of biochemical and 16S rDNA gene sequence analysis. Minimum inhibitory concentration for this bacterium was 40 AU mL(-1) against S. aureus. The antibacterial activity of this bacterium was stable after autoclaving, 10% SDS, boiling, and proteinase K. Thin layer chromatography, using anthrone reagent, showed the presence of carbohydrates in the purified antibacterial compound. Finally, FT-IR spectrum of the active compound illustrated hydroxyl groups, hydrocarbon skeleton, and double bond of polygenic compounds in its structure. To the best of our knowledge, this is the first report describing the efficient antibacterial activity by a local strain of Pseudonocardia. The results presented in this work, although at the initial stage in bioactive product characterization, will possibly contribute toward the Pseudonocardia scale-up for the production and identification of the antibacterial compounds.

  5. Evaluation of antibacterial activity of N-phosphonium chitosan as a novel polymeric antibacterial agent.

    Science.gov (United States)

    Guo, Aijie; Wang, Feihu; Lin, Wentao; Xu, Xiaofen; Tang, Tingting; Shen, Yuanyuan; Guo, Shengrong

    2014-06-01

    N-phosphonium chitosans (NPCSs) with different degrees of substitution (3%, 13% and 21%) were synthesized and evaluated as novel polymeric antibacterial agents. Their antibacterial activities compared with hydroxypropyltrimethyl ammonium chloride chitosan (HACC), parent chitosan and (5-carboxypentyl) triphenylphosphonium bromide (CTPB) were tested against Escherichia coli and two strains of drug-resistance Staphylococcus aureus by minimal inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and biofilm prevention assays. The results show that the NPCS with 3% or 13% substitution has lower MIC and MBC values and stronger ability to inhibit biofilm formation of all the three bacteria than HACC, chitosan and CTPB. In addition, the antibacterial activity of NPCSs increases with their substitution decreasing from 21% to 3%. Overall, the antibacterial activity of NPCS with 3% or 13% substitution is better than that of NPCS with 21% substitution, HACC with 22% substitution, chitosan and CTPB. It can be considered that NPCS with appropriate degree of substitution has favorable antibacterial activity and is a potential polymeric antibacterial agent.

  6. Antibacterial and Antibiofilm Activities of Makaluvamine Analogs

    Directory of Open Access Journals (Sweden)

    Bhavitavya Nijampatnam

    2014-09-01

    Full Text Available Streptococcus mutans is a key etiological agent in the formation of dental caries. The major virulence factor is its ability to form biofilms. Inhibition of S. mutans biofilms offers therapeutic prospects for the treatment and the prevention of dental caries. In this study, 14 analogs of makaluvamine, a marine alkaloid, were evaluated for their antibacterial activity against S. mutans and for their ability to inhibit S. mutans biofilm formation. All analogs contained the tricyclic pyrroloiminoquinone core of makaluvamines. The structural variations of the analogs are on the amino substituents at the 7-position of the ring and the inclusion of a tosyl group on the pyrrole ring N of the makaluvamine core. The makaluvamine analogs displayed biofilm inhibition with IC50 values ranging from 0.4 μM to 88 μM. Further, the observed bactericidal activity of the majority of the analogs was found to be consistent with the anti-biofilm activity, leading to the conclusion that the anti-biofilm activity of these analogs stems from their ability to kill S. mutans. However, three of the most potent N-tosyl analogs showed biofilm IC50 values at least an order of magnitude lower than that of bactericidal activity, indicating that the biofilm activity of these analogs is more selective and perhaps independent of bactericidal activity.

  7. Antibacterial activity and toxicity of silver - nanosilver versus ionic silver

    Energy Technology Data Exchange (ETDEWEB)

    Kvitek, L; Panacek, A; Prucek, R; Soukupova, J; Vanickova, M; Zboril, R [Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University, 17. Listopadu 12, 77146 Olomouc (Czech Republic); Kolar, M, E-mail: ales.panacek@upol.cz [Department of Microbiology, Faculty of Medicine and Dentistry, Palacky University, Hnevotinska 3, 77520 Olomouc (Czech Republic)

    2011-07-06

    The in vitro study of antibacterial activity of silver nanoparticles (NPs), prepared via modified Tollens process, revealed high antibacterial activity even at very low concentrations around several units of mg/L. These concentrations are comparable with concentrations of ionic silver revealing same antibacterial effect. However, such low concentrations of silver NPs did not show acute cytotoxicity to mammalian cells - this occurs at concentrations higher than 60 mg/L of silver, while the cytotoxic level of ionic silver is much more lower (approx. 1 mg/L). Moreover, the silver NPs exhibit lower acute ecotoxicity against the eukaryotic organisms such as Paramecium caudatum, Monoraphidium sp. and D. melanogaster. The silver NPs are toxic to these organisms at the concentrations higher than 30 mg/L of silver. On contrary, ionic silver retains its cytoxicity and ecotoxicity even at the concentration equal to 1 mg/L. The performed experiments demonstrate significantly lower toxicity of silver NPs against the eukaryotic organisms than against the prokaryotic organisms.

  8. Antibacterial activity and toxicity of silver - nanosilver versus ionic silver

    Science.gov (United States)

    Kvitek, L.; Panacek, A.; Prucek, R.; Soukupova, J.; Vanickova, M.; Kolar, M.; Zboril, R.

    2011-07-01

    The in vitro study of antibacterial activity of silver nanoparticles (NPs), prepared via modified Tollens process, revealed high antibacterial activity even at very low concentrations around several units of mg/L. These concentrations are comparable with concentrations of ionic silver revealing same antibacterial effect. However, such low concentrations of silver NPs did not show acute cytotoxicity to mammalian cells - this occurs at concentrations higher than 60 mg/L of silver, while the cytotoxic level of ionic silver is much more lower (approx. 1 mg/L). Moreover, the silver NPs exhibit lower acute ecotoxicity against the eukaryotic organisms such as Paramecium caudatum, Monoraphidium sp. and D. melanogaster. The silver NPs are toxic to these organisms at the concentrations higher than 30 mg/L of silver. On contrary, ionic silver retains its cytoxicity and ecotoxicity even at the concentration equal to 1 mg/L. The performed experiments demonstrate significantly lower toxicity of silver NPs against the eukaryotic organisms than against the prokaryotic organisms.

  9. Design, synthesis and antibacterial activity of a novel hybrid ...

    African Journals Online (AJOL)

    ajl user 1

    2012-01-26

    Jan 26, 2012 ... Antimicrobial peptides produced by many tissues and cell types of invertebrates, insects and humans as part of ... Key words: Antimicrobial peptides, design, LfcinB, melittin, antibacterial activity. ... from the Heilongjiang Type Culture Collection (Harbin, China). .... antibacterial experiments were carried out.

  10. ANTIBACTERIAL ACTIVITY TEST OF EXTRACT NYAMPLUNG (Calophyllum inophyllum Linn. LEAVES

    Directory of Open Access Journals (Sweden)

    Mutiara Novianti

    2015-09-01

    Full Text Available Phytochemical screening and antibacterial activity from ethanol extract of nyamplung (Callophylum inophyllum Linn. leaves from Indonesia against Escherichia coli has been done. The extraction was done by soklet extraction using ethanol. Antibacterial activity test using the Optical Density method at λmax 600 nm. The result of phytochemical screening from ethanol extract showed that there were flavonoid compounds, saponins, tannins, phenols and triterpenoids. The result of antibacterial activity test showed that the optimum activity occurs at incubation time of 3 hours with percentase inhibition persentase i.e. 59.03 %.

  11. Antibacterial activity of papain hydrolysed camel whey and its fractions

    DEFF Research Database (Denmark)

    Abdel-Hamid, Mahmoud; Goda, Hanan A.; De Gobba, Cristian

    2016-01-01

    Camel whey (ON) was hydrolysed with papain from Carica papaya and fractionated by size exclusion chromatography (SEC). The antibacterial activity of the CW, camel whey hydrolysate (CWH) and the obtained SEC-fractions was assessed using the disc-diffusion method. The CWH exhibited significantly...... higher antibacterial activity than the unhydrolysed ON. SEC-F2 (fraction 2) exhibited the highest antibacterial activity against Staphylococcus aureus, whereas Escherichia coli was the least affected. Transmission electron microscopy (TEM) micrographs showed that the SEC-F2 caused changes in the treated...

  12. Antibacterial activity and physicochemical evaluation of roots of Butea monosperma

    Institute of Scientific and Technical Information of China (English)

    Prashant Tiwari; Ritesh Jain; Kuldeep Kumar; Rahul Mishra; Anish Chandy

    2012-01-01

    Objective: To evaluate the antibacterial activity of the petroleum ether extract of root of Buteamonosperma B. monosperma was studied against Staphylococcus faecalis (S. faecalis), Sterptococcus faecalis (S. faecalis), Aeromonas hydrophilia (A. hydrophilia), Salmonela typhae (S. typhae), Stphylococcus cohni (S. cohni), Escherichia coli (E. coli) and Serratia ficaria (S. ficaria) by using well diffusion method. Results: Petroleum ether extract of root of B. monosperma exhibited a prominent inhibitory effect against bacterial strains. Conclusion: From the result it can be concluded that the B. monosperma extract has potent in vitro antibacterial activity. (B. monosperma). Method: In vitro antibacterial activity of petroleum ether i.e.

  13. Phytochemical constituents and antibacterial activity of some green leafy vegetables

    Institute of Scientific and Technical Information of China (English)

    Ramesa Shafi Bhat; Sooad Al-Daihan

    2014-01-01

    Objective: To investigate the antibacterial activity and photochemicals of five green leafy vegetables against a panel of five bacteria strains. Methods: Disc diffusion method was used to determine the antibacterial activity, while kanamycin was used as a reference antibiotic. The phytochemical screening of the extracts was performed using standard methods. Results:All methanol extracts were found active against all the test bacterial strains. Overall maximum extracts shows antibacterial activity which range from 6 to 15 mm. Proteins and carbohydrates was found in all the green leaves, whereas alkaloid, steroids, saponins, flavonoids, tannins were found in most of the test samples. Conclusions:The obtain result suggests that green leafy vegetables have moderate antibacterial activity and contain various pharmacologically active compounds and thus provide the scientific basis for the traditional uses of the studied vegetables in the treatment of bacterial infections.

  14. Comparative study of antibacterial activity of wood-decay fungi and antibiotics

    OpenAIRE

    A. F. Md. Hassan Iftekhar; Zubaida Khatoon Choudhry; Md. Ismail Khan; Ahmed Abu Saleh

    2011-01-01

    The antibacterial effects of three mushrooms extract Ganoderma lucidum, Auricularia auricula, Pleurotus florida were studied against Staphylococcus aureus and Escherichia coli. A. auricula showed significant antibacterial activity against S. aureus. P. florida showed some antibacterial activity while G. lucidum showed no antibacterial activity. None of the extracts showed any activity against E. coli.

  15. Antibacterial activity from Siamese crocodile (Crocodylus siamensis ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-09-03

    Sep 3, 2008 ... alligator has shown a broad spectrum of antibiotic effects on bacteria, fungi and ..... antibacterial peptides from honeybees. EMBO J. 8: ... Structure and organization of the human antimicrobial peptide LL-37 in phospholipid ...

  16. Antibacterial Activity of Dental Cements Containing Quaternary Ammonium Polyethylenimine Nanoparticles

    Directory of Open Access Journals (Sweden)

    Nurit Beyth

    2012-01-01

    Full Text Available Glass ionomer cements (GICs are commonly used for cementing full cast crown restorations. Regrettably, although the dental cements fill the gap between the tooth and the crown, bacterial microleakage may occur, resulting in secondary caries. As microleakage cannot be completely prevented, GICs possessing antibacterial properties are in demand. In the present study the antibacterial activity of insoluble, cross-linked quaternary ammonium polyethylenimine (QPEI nanoparticles incorporated at 1% w/w in two clinically available GICs were studied. The antibacterial activity was tested against Streptococcus mutans and Lactobacillus casei using the direct contact test (DCT and the agar diffusion test (ADT. Using the direct contact test, antibacterial activity (<0.05 was found in both tested GICs with incorporated QPEI nanoparticles, the effect lasting for at least one month. However, the ADT showed no inhibition halo in the test bacteria, indicating that the antimicrobial nanoparticles do not diffuse into the agar. The results show that the incorporation of QPEI nanoparticles in glass ionomer cements has a long-lasting antibacterial effect against Streptococcus mutans and Lactobacillus casei. Changing the antibacterial properties of glass ionomer cements by incorporating QPEI antibacterial nanoparticles may prolong the clinical performance of dental crowns.

  17. Evaluation of antibacterial activity of flowering plants and ...

    African Journals Online (AJOL)

    GREGORY

    2011-12-16

    Dec 16, 2011 ... antibacterial compound was carried out using this plant. The best conditions ... Organization, approximately 30% of people in Indus- trialized ... process conditions is important as it gives impact to the economy .... tics activity.

  18. Antibacterial activity of Sargassum polycystum C. Agardh and ...

    African Journals Online (AJOL)

    The antibacterial activity against Gram-negative bacteria (beta-lactamase positive ... aeruginosa) and Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus) ... Gram-positive bacteria especially B. cereus was more susceptible to the ...

  19. Antibacterial activities of the crude ethanol extracts of medicinal ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-07-05

    Jul 5, 2010 ... Full Length Research Paper. Antibacterial activities of the ... meats and vegetable products (Schlech III, 2000). ... products with antimicrobial properties has been explored. (Gould, 1996 ..... isolated from meat. Appl. Environ.

  20. Antibacterial activity of mangrove leaf extracts against human pathogens

    Digital Repository Service at National Institute of Oceanography (India)

    Sahoo, G.; Mulla, N.S.S.; Ansari, Z.A.; Mohandass, C.

    The antibacterial activity of leaf extract of mangroves, namely, Rhizophora mucronata, Sonneratia alba and Exoecaria agallocha from Chorao island, Goa was investigated against human bacterial pathogens Staphylococcus aureus, Streptococcus sp...

  1. Antibacterial activity of water-phase extracts from bamboo shavings ...

    African Journals Online (AJOL)

    Antibacterial activity of water-phase extracts from bamboo shavings against food spoilage microorganisms. ... African Journal of Biotechnology ... was evaluated for its antimicrobial action against the range of food borne and food spoilage ...

  2. In Vitro antibacterial activity of rumex nervosus, plantago lanceolata ...

    African Journals Online (AJOL)

    Lepidium sativum and Solanum incanum did not have any antibacterial activity against all the cultured .... shaker and the resulting supernatant was filtered using filter paper (Whatman. No.1) with particle ..... soluble chitosan derivatives. J. Appl.

  3. Antibacterial Activity of Copper and Cobalt Amino Acids Complexes

    Directory of Open Access Journals (Sweden)

    ANDREEA STĂNILĂ

    2011-11-01

    Full Text Available The antibacterial properties of differently copper and cobalt amino acids complexes on agar plates was investigated in the present study. The antibacterial activity of amino acid complexes was evaluated against on three bacteria strains (Escherichia coli, Bacillus cereus, Micrococcus luteus. Generally, the amino acids complexes were mainly active against gram-positive organisms, species like Micrococcus luteus being the most susceptible strain tested. It was registered a moderate antibacterial activity against Bacillus cereus. The microorganisms Escherichia coli, which are already known to be multi-resistant to drugs, were also resistant to the amino acids complexes but also to the free salts tested. Escherichia coli were susceptible only to the CoCl2 and copper complex with phenylalanine. The complexes with leucine and histidine seem to be more active than the parent free ligand against one or more bacterial species. Moderate activity was registered in the case of complexes with methionine and phenylalanine. From the complexes tested less efficient antibacterial activity was noted in the case of complexes with lysine and valine. These results show that cobalt and copper complexes have an antibacterial activity and suggest their potential application as antibacterial agents.

  4. Antibacterial Activity of Eel (Anguilla spp.) Mucus against Salmonella typhi

    OpenAIRE

    Tomy Nurtamin; Resty Yulianita Nurman; Indria Hafizah

    2016-01-01

    BACKGROUND: Typhoid fever has become one global health problem. Typhoid fever is caused by a Gram-negative bacterium, Salmonella typhi. Eel (Anguilla spp.) is a fish which lives in the sea or in freshwater. Several previous studies have found that Anguilla spp. mucus has the ability as antibacterial against Gram-positive and negative. Although the antibacterial activity of Anguilla spp. against various pathogens had been reported, very little is known about its activity against Salmonella typ...

  5. Enhanced transparency, mechanical durability, and antibacterial activity of zinc nanoparticles on glass substrate

    Science.gov (United States)

    Choi, Hyung-Jin; Choi, Jin-Seok; Park, Byeong-Ju; Eom, Ji-Ho; Heo, So-Young; Jung, Min-Wook; An, Ki-Seok; Yoon, Soon-Gil

    2014-09-01

    Homogeneously distributed zinc nanoparticles (NPs) on the glass substrate were investigated for the transmittance, mechanical durability, and antibacterial effect. The buffered Ti NPs between Zn NPs and glass substrate were studied for an enhancement of the transmittance and mechanical endurance. The Ti NPs buffered Zn NPs showed a high transmittance of approximately 91.5% (at a wavelength of 550 nm) and a strong antibacterial activity for Staphylococcus aureus and Escherichia coli bacteria. The buffered Ti NPs are attractive for an excellent mechanical endurance of the Zn NPs. The Zn NPs did not require the protection layer to prevent the degradation of the performance for both the antibacterial effect and the transmittance.

  6. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro

    OpenAIRE

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, RS; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity s...

  7. Highly Efficient F, Cu doped TiO2 anti-bacterial visible light active photocatalytic coatings to combat hospital-acquired infections

    Science.gov (United States)

    Leyland, Nigel S.; Podporska-Carroll, Joanna; Browne, John; Hinder, Steven J.; Quilty, Brid; Pillai, Suresh C.

    2016-04-01

    Bacterial infections are a major threat to the health of patients in healthcare facilities including hospitals. One of the major causes of patient morbidity is infection with Staphylococcus aureus. One of the the most dominant nosocomial bacteria, Methicillin Resistant Staphylococcus aureus (MRSA) have been reported to survive on hospital surfaces (e.g. privacy window glasses) for up to 5 months. None of the current anti-bacterial technology is efficient in eliminating Staphylococcus aureus. A novel transparent, immobilised and superhydrophilic coating of titanium dioxide, co-doped with fluorine and copper has been prepared on float glass substrates. Antibacterial activity has demonstrated (by using Staphylococcus aureus), resulting from a combination of visible light activated (VLA) photocatalysis and copper ion toxicity. Co-doping with copper and fluorine has been shown to improve the performance of the coating, relative to a purely fluorine-doped VLA photocatalyst. Reductions in bacterial population of log10 = 4.2 under visible light irradiation and log10 = 1.8 in darkness have been achieved, compared with log10 = 1.8 under visible light irradiation and no activity, for a purely fluorine-doped titania. Generation of reactive oxygen species from the photocatalytic coatings is the major factor that significantly reduces the bacterial growth on the glass surfaces.

  8. Highly antibacterial activity of N-doped TiO{sub 2} thin films coated on stainless steel brackets under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Shuai; Liu, Bo; Fan, Lingying; Yue, Ziqi [Department of Orthodontics, School of Stomatology, Lanzhou University, Lanzhou 730000 (China); Liu, Bin [Department of Materials Science, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000 (China); Cao, Baocheng, E-mail: caobch@lzu.edu.cn [Department of Orthodontics, School of Stomatology, Lanzhou University, Lanzhou 730000 (China)

    2014-08-01

    In this study, the radio frequency (RF) magnetron sputtering method was used to prepare a TiO{sub 2} thin film on the surface of stainless steel brackets. Eighteen groups of samples were made according to the experimental parameters. The crystal structure and surface morphology were characterized by X-ray diffraction, and scanning electron microscopy, respectively. The photocatalytic properties under visible light irradiation were evaluated by measuring the degradation ratio of methylene blue. The sputtering temperature was set at 300 °C, and the time was set as 180 min, the ratio of Ar to N was 30:1, and annealing temperature was set at 450 °C. The thin films made under these parameters had the highest visible light photocatalytic activity of all the combinations of parameters tested. Antibacterial activities of the selected thin films were also tested against Lactobacillus acidophilus and Candida albicans. The results demonstrated the thin film prepared under the parameters above showed the highest antibacterial activity.

  9. Highly antibacterial activity of N-doped TiO2 thin films coated on stainless steel brackets under visible light irradiation

    Science.gov (United States)

    Cao, Shuai; Liu, Bo; Fan, Lingying; Yue, Ziqi; Liu, Bin; Cao, Baocheng

    2014-08-01

    In this study, the radio frequency (RF) magnetron sputtering method was used to prepare a TiO2 thin film on the surface of stainless steel brackets. Eighteen groups of samples were made according to the experimental parameters. The crystal structure and surface morphology were characterized by X-ray diffraction, and scanning electron microscopy, respectively. The photocatalytic properties under visible light irradiation were evaluated by measuring the degradation ratio of methylene blue. The sputtering temperature was set at 300 °C, and the time was set as 180 min, the ratio of Ar to N was 30:1, and annealing temperature was set at 450 °C. The thin films made under these parameters had the highest visible light photocatalytic activity of all the combinations of parameters tested. Antibacterial activities of the selected thin films were also tested against Lactobacillus acidophilus and Candida albicans. The results demonstrated the thin film prepared under the parameters above showed the highest antibacterial activity.

  10. Silver colloid nanoparticles: synthesis, characterization, and their antibacterial activity.

    Science.gov (United States)

    Panacek, Ales; Kvítek, Libor; Prucek, Robert; Kolar, Milan; Vecerova, Renata; Pizúrova, Nadezda; Sharma, Virender K; Nevecna, Tat'jana; Zboril, Radek

    2006-08-24

    A one-step simple synthesis of silver colloid nanoparticles with controllable sizes is presented. In this synthesis, reduction of [Ag(NH(3))(2)](+) complex cation by four saccharides was performed. Four saccharides were used: two monosaccharides (glucose and galactose) and two disaccharides (maltose and lactose). The syntheses performed at various ammonia concentrations (0.005-0.20 mol L(-1)) and pH conditions (11.5-13.0) produced a wide range of particle sizes (25-450 nm) with narrow size distributions, especially at the lowest ammonia concentrations. The average size, size distribution, morphology, and structure of particles were determined by dynamic light scattering (DLS), transmission electron microscopy (TEM), and UV/Visible absorption spectrophotometry. The influence of the saccharide structure (monosacharides versus disaccharides) on the size of silver particles is briefly discussed. The reduction of [Ag(NH(3))(2)](+) by maltose produced silver particles with a narrow size distribution with an average size of 25 nm, which showed high antimicrobial and bactericidal activity against Gram-positive and Gram-negative bacteria, including highly multiresistant strains such as methicillin-resistant Staphylococcus aureus. Antibacterial activity of silver nanoparticles was found to be dependent on the size of silver particles. A very low concentration of silver (as low as 1.69 mug/mL Ag) gave antibacterial performance.

  11. Antibacterial activities, DFT and QSAR studies of quinazolinone compounds

    Directory of Open Access Journals (Sweden)

    A. G. Al-Sehemi

    2016-08-01

    Full Text Available The quinazolinone compounds (1 and 2 in this work were examined for their in vitro antibacterial activities against gram-positive (Staphylococcus aureus and gram-negative bacteria (Klebsiella pneumonia, Proteus bacilli and Shigella flexneri. Compared to the reference antibiotic chloramphenicol, these compounds showed high antibacterial activities against studied strains with inhibition zones observation. The ground state geometries have been optimized by using density functional theory (DFT at B3LYP/6-31G* level of theory. The absorption spectra have been calculated by using time dependent density functional theory (TDDFT with and without solvent. The effect of different functionals (B3LYP, MPW1PW91, and PBE1PBE on the absorption wavelengths has been studied. The ionization potential (IP, electron affinity (EA, energy gap (Egap, electronegativity (χ, hardness (η, electrophilicity (ω, softness (S and electrophilicity index (ωi were computed and discussed. The nonlinear optical (NLO properties vary by changing the theory (DFT to HF or functional (B3LYP to CAM-B3LYP. The physicochemical parameters have been studied by quantitative structure–activity relationship (QSAR. The computed properties of investigated compounds have been compared with the Chloramphenicol as well as available experimental data.

  12. Antibacterial Activity of Copaiba Oil Gel on Dental Biofilm

    OpenAIRE

    Simões, Cláudia A.C.G.; Conde, Nikeila C. de Oliveira; Venâncio, Gisely N.; Milério, Patrícia S.L.L.; Bandeira, Maria F.C.L.; da Veiga Júnior, Valdir F.

    2016-01-01

    Amazonian biodiversity products that have been used for years in folk medicine, have emerged as feasible and promising alternatives for the inhibition of microorganisms in dental biofilm. Copaiba oil, a phytotherapic agent widely used by the Amazonian populations, is known for its antibacterial, anti-inflammatory, anesthetic, healing and antitumor medicinal properties. Objective: The aim of this study was to evaluate the in vitro antibacterial activity of copaiba oil (Copaifera multijuga) gel...

  13. Purification and Activity of Antibacterial Substances Derived from Soil Streptomyces sp.CaiF1

    Institute of Scientific and Technical Information of China (English)

    Hui YANG; Guixiang PENG; Jianmin ZENG; Zhiyuan TAN

    2012-01-01

    [Objective] This study aimed to separate and purify antibacterial sub- stances from soil Streptomyces sp. CaiF1, and to explore the activities of this sub- stance. [Method] The antibacterial substances were separated and purified by Ethyl acetate extraction, macroporous adsorptive resin, silica gel chromatography and preparative high performance liquid chromatography (HPLC), and powdery mildew were taken as the indicating bacterial to study their activities. [Result] Antibacterial substances were purified and the stability analysis of the extracts from Streptomyces CaiF1 fermentation broth showed very stable at pH 2.0-pH 10.0, 100 ~C and changed very little under UV treatment for 24 h. Inhibition rate of powdery mildew was 69.7%. [Conclusion] The purified antibacterial substances showed good stability, which provided theoretical foundation for their structural identifications and future ap- plications.

  14. Negatively charged silver nanoparticles with potent antibacterial activity and reduced toxicity for pharmaceutical preparations.

    Science.gov (United States)

    Salvioni, Lucia; Galbiati, Elisabetta; Collico, Veronica; Alessio, Giulia; Avvakumova, Svetlana; Corsi, Fabio; Tortora, Paolo; Prosperi, Davide; Colombo, Miriam

    2017-01-01

    The discovery of new solutions with antibacterial activity as efficient and safe alternatives to common preservatives (such as parabens) and to combat emerging infections and drug-resistant bacterial pathogens is highly expected in cosmetics and pharmaceutics. Colloidal silver nanoparticles (NPs) are attracting interest as novel effective antimicrobial agents for the prevention of several infectious diseases. Water-soluble, negatively charged silver nanoparticles (AgNPs) were synthesized by reduction with citric and tannic acid and characterized by transmission electron microscopy, dynamic light scattering, zeta potential, differential centrifuge sedimentation, and ultraviolet-visible spectroscopy. AgNPs were tested with model Gram-negative and Gram-positive bacteria in comparison to two different kinds of commercially available AgNPs. In this work, AgNPs with higher antibacterial activity compared to the commercially available colloidal silver solutions were prepared and investigated. Bacteria were plated and the antibacterial activity was tested at the same concentration of silver ions in all samples. The AgNPs did not show any significant reduction in the antibacterial activity for an acceptable time period. In addition, AgNPs were transferred to organic phase and retained their antibacterial efficacy in both aqueous and nonaqueous media and exhibited no toxicity in eukaryotic cells. We developed AgNPs with a 20 nm diameter and negative zeta potential with powerful antibacterial activity and low toxicity compared to currently available colloidal silver, suitable for cosmetic preservatives and pharmaceutical preparations administrable to humans and/or animals as needed.

  15. Investigation of the chemical composition-antibacterial activity relationship of essential oils by chemometric methods.

    Science.gov (United States)

    Miladinović, Dragoljub L; Ilić, Budimir S; Mihajilov-Krstev, Tatjana M; Nikolić, Nikola D; Miladinović, Ljiljana C; Cvetković, Olga G

    2012-05-01

    The antibacterial effects of Thymus vulgaris (Lamiaceae), Lavandula angustifolia (Lamiaceae), and Calamintha nepeta (Lamiaceae) Savi subsp. nepeta var. subisodonda (Borb.) Hayek essential oils on five different bacteria were estimated. Laboratory control strain and clinical isolates from different pathogenic media were researched by broth microdilution method, with an emphasis on a chemical composition-antibacterial activity relationship. The main constituents of thyme oil were thymol (59.95%) and p-cymene (18.34%). Linalool acetate (38.23%) and β-linalool (35.01%) were main compounds in lavender oil. C. nepeta essential oil was characterized by a high percentage of piperitone oxide (59.07%) and limonene (9.05%). Essential oils have been found to have antimicrobial activity against all tested microorganisms. Classification and comparison of essential oils on the basis of their chemical composition and antibacterial activity were made by utilization of appropriate chemometric methods. The chemical principal component analysis (PCA) and hierachical cluster analysis (HCA) separated essential oils into two groups and two sub-groups. Thyme essential oil forms separate chemical HCA group and exhibits highest antibacterial activity, similar to tetracycline. Essential oils of lavender and C. nepeta in the same chemical HCA group were classified in different groups, within antibacterial PCA and HCA analyses. Lavender oil exhibits higher antibacterial ability in comparison with C. nepeta essential oil, probably based on the concept of synergistic activity of essential oil components.

  16. Soya bean tempe extracts show antibacterial activity against Bacillus cereus cells and spores.

    Science.gov (United States)

    Roubos-van den Hil, P J; Dalmas, E; Nout, M J R; Abee, T

    2010-07-01

    Tempe, a Rhizopus ssp.-fermented soya bean food product, was investigated for bacteriostatic and/or bactericidal effects against cells and spores of the food-borne pathogen Bacillus cereus. Tempe extract showed a high antibacterial activity against B. cereus ATCC 14579 based on optical density and viable count measurements. This growth inhibition was manifested by a 4 log CFU ml(-1) reduction, within the first 15 min of exposure. Tempe extracts also rapidly inactivated B. cereus spores upon germination. Viability and membrane permeability assessments using fluorescence probes showed rapid inactivation and permeabilization of the cytoplasmic membrane confirming the bactericidal mode of action. Cooked beans and Rhizopus grown on different media did not show antibacterial activity, indicating the unique association of the antibacterial activity with tempe. Subsequent characterization of the antibacterial activity revealed that heat treatment and protease addition nullified the bactericidal effect, indicating the proteinaceous nature of the bioactive compound. During fermentation of soya beans with Rhizopus, compounds are released with extensive antibacterial activity against B. cereus cells and spores. The results show the potential of producing natural antibacterial compounds that could be used as ingredients in food preservation and pathogen control. © 2009 The Authors. Journal compilation © 2009 The Society for Applied Microbiology.

  17. Studies on the antibacterial activity of dodecylglycerol

    Energy Technology Data Exchange (ETDEWEB)

    Brissette, J.L.

    1985-01-01

    The antimicrobial activity of lipids has been known for many years, with dodecanoylglycerol (dodecanoic acid esterified to glycerol) being one of the most potential. However, the antibacterial potency of dodecylglycerol (DDG), the corresponding 1-O-alkyl glycerol ether, is considerably greater. The superior efficacy of DDG can be attributed, at least in part, to the greater chemical and metabolic stability of the ether bond as compared to esters. In an attempt towards elucidating the mode of action of DDG, the effect of DDG on bacterial lipid metabolism was examined using Streptococcus mutans BHT, a tolerant bacterium. The metabolic fate of the ether was also determined with the use of three radioactive tracers, /sup 14/C-glycerol, /sup 32/Pi, and /sup 14/C-DDG. Treatment of exponentially growing cultures of S. mutans BHI with growth inhibitory concentrations of DDG (10 and 20 ..mu..g/ml) inhibited the incorporation of /sup 14/C-glycerol into lipid. In vivo studies using /sup 14/C-DDG showed that the /sup 14/C-ether was readily incorporated almost exclusively into phosphatidic (PA) and lysophosphatidic (LPA) acids. When cells prelabelled with either /sup 14/C-glycerol or /sup 32/Pi were exposed to 10 and 20 /sup +/g/ml DDG for 2 h, the accumulation of PA and diphosphatidylglycerol (diPG) was greatly stimulated. However, diPG accumulated at the expense of its precursor, glycerol, which greatly decreased. These data suggest that the ether-containing PA inhibits the synthesis of CDP-diglyceride. Moreover, these results clearly demonstrate that DDG functions as a metabolic rather than physical effector, disputing the conventional notion that bactericidal lipids act as detergents, physically dissolving the cellular envelope.

  18. Antibacterial activity of nanocomposites of copper and cellulose.

    Science.gov (United States)

    Pinto, Ricardo J B; Daina, Sara; Sadocco, Patrizia; Pascoal Neto, Carlos; Trindade, Tito

    2013-01-01

    The design of cheap and safe antibacterial materials for widespread use has been a challenge in materials science. The use of copper nanostructures combined with abundant biopolymers such as cellulose offers a potential approach to achieve such materials though this has been less investigated as compared to other composites. Here, nanocomposites comprising copper nanofillers in cellulose matrices have been prepared by in situ and ex situ methods. Two cellulose matrices (vegetable and bacterial) were investigated together with morphological distinct copper particulates (nanoparticles and nanowires). A study on the antibacterial activity of these nanocomposites was carried out for Staphylococcus aureus and Klebsiella pneumoniae, as pathogen microorganisms. The results showed that the chemical nature and morphology of the nanofillers have great effect on the antibacterial activity, with an increase in the antibacterial activity with increasing copper content in the composites. The cellulosic matrices also show an effect on the antibacterial efficiency of the nanocomposites, with vegetal cellulose fibers acting as the most effective substrate. Regarding the results obtained, we anticipate the development of new approaches to prepare cellulose/copper based nanocomposites thereby producing a wide range of interesting antibacterial materials with potential use in diverse applications such as packaging or paper coatings.

  19. Solvent Free Synthesis of Chalcones and their Antibacterial Activities

    Directory of Open Access Journals (Sweden)

    K. Rajendra K. Saini

    2005-01-01

    Full Text Available The solvent free synthesis of six chalcones was carried out by grinding the piperanal and the acetophenone (unsubstituted, 4-methyl, 4-methoxy, 4-bromo, 4-nitro, 3-chloro in the presence of solid sodium hydroxide with a mortar and pestle. In general, the chalcones were obtained in high yield and high purity. Minor quantities of Ketol and Michael addition product were easily removed by recrystallization. The result indicates a correlation between the success of the solvent-free synthesis and melting point of the chalcone. Chalcone with relatively high melting points (higher than 80°C were obtained in high yields. The two chalcones that could not be produced in good yields were having relatively low melting points. They have been screened for their antibacterial activity against Gram positive and Gram negative bacteria.

  20. Highly Absorbent Antibacterial Hemostatic Dressing for Healing Severe Hemorrhagic Wounds

    Directory of Open Access Journals (Sweden)

    Ting-Ting Li

    2016-09-01

    Full Text Available To accelerate healing of severe hemorrhagic wounds, a novel highly absorbent hemostatic dressing composed of a Tencel®/absorbent-cotton/polylactic acid nonwoven base and chitosan/nanosilver antibacterial agent was fabricated by using a nonwoven processing technique and a freeze-drying technique. This study is the first to investigate the wicking and water-absorbing properties of a nonwoven base by measuring the vertical wicking height and water absorption ratio. Moreover, blood agglutination and hemostatic second tests were conducted to evaluate the hemostatic performance of the resultant wound dressing. The blending ratio of fibers, areal weight, punching density, and fiber orientation, all significantly influenced the vertical moisture wicking property. However, only the first two parameters markedly affected the water absorption ratio. After the nonwoven base absorbed blood, scanning electron microscope (SEM observation showed that erythrocytes were trapped between the fibrin/clot network and nonwoven fibers when coagulation pathways were activated. Prothrombin time (PT and activated partial thromboplastin time (APTT blood agglutination of the resultant dressing decreased to 14.34 and 50.94 s, respectively. In the femoral artery of the rate bleeding model, hemostatic time was saved by 87.2% compared with that of cotton cloth. Therefore, the resultant antibacterial wound dressing demonstrated greater water and blood absorption, as well as hemostatic performance, than the commercially available cotton cloth, especially for healing severe hemorrhagic wounds.

  1. Antibacterial activity and qualitative phytochemical analysis of Vitex mollis fruit

    Directory of Open Access Journals (Sweden)

    Delgado-Vargas Francisco

    2010-01-01

    Full Text Available The pulp of the Vitex mollis fruit is edible and traditionally used to treat diarrhoea. The antibacterial activity of this fruit is reported here for the first time. The fruit pulp was extracted with methanol (ME and the extract was fractionated with solvents. ME and their fractions [hexanic (HF, chloroformic (CF, ethyl acetate (EAF and aqueous (AqF] were assayed against human pathogenic bacteria (microdilution test and their phytochemicals determined (qualitative chemical determinations. The samples (i.e., ME, HE, CF, EAF and AqF showed antibacterial activity; EAF was the most active, showing such activity against Shigella dysenteriae [minimal inhibitory concentration (MIC=2 mg/ml]. Phenolics were mainly found in ME and EAF; compounds of this chemical family are well known for their antidiarrhoeal and antimicrobial activities. The reported antibacterial activity and phenolics content of V. mollis fruit could be associated with its use in the treatment of diarrhoea.

  2. Antibacterial activity of silver nanoparticles synthesized from serine.

    Science.gov (United States)

    Jayaprakash, N; Judith Vijaya, J; John Kennedy, L; Priadharsini, K; Palani, P

    2015-04-01

    Silver nanoparticles (Ag NPs) were synthesized by a simple microwave irradiation method using polyvinyl pyrrolidone (PVP) as a capping agent and serine as a reducing agent. UV-Visible spectra were used to confirm the formation of Ag NPs by observing the surface plasmon resonance (SPR) band at 443nm. The emission spectrum of Ag NPs showed an emission band at 484nm. In the presence of microwave radiation, serine acts as a reducing agent, which was confirmed by Fourier transformed infrared (FT-IR) spectrum. High-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning electron microscopy (HR-SEM) were used to investigate the morphology of the synthesized sample. These images showed the sphere-like morphology. The elemental composition of the sample was determined by the energy dispersive X-ray analysis (EDX). Selected area electron diffraction (SAED) was used to find the crystalline nature of the Ag NPs. The electrochemical behavior of the synthesized Ag NPs was analyzed by the cyclic voltammetry (CV). Antibacterial experiments showed that the prepared Ag NPs showed relatively similar antibacterial activities, when compared with AgNO3 against Gram-positive and Gram-negative bacteria.

  3. Antibacterial Activity of the Extracts Obtained from Rosmarinus officinalis, Origanum majorana, and Trigonella foenum-graecum on Highly Drug-Resistant Gram Negative Bacilli

    Directory of Open Access Journals (Sweden)

    Roula Abdel-Massih

    2010-01-01

    Full Text Available Our aim was to determine the antimicrobial activity of three selected plants (Rosmarinus officinalis, Origanum majorana, and Trigonella foenum-graecum against Extended Spectrum Beta Lactamase (ESBL—producing Escherichia coli and Klebsiella pneumoniae— and to identify the specific plant fraction responsible for the antimicrobial activity. The plants were extracted with ethanol to yield the crude extract which was further subfractionated by different solvents to obtain the petroleum ether, the dichloromethane, the ethyl acetate, and the aqueous fractions. The Minimum Inhibitory Concentrations (MIC and Minimum Bactericidal Concentrations (MBC were determined using broth microdilution. The MICs ranged between 1.25 and 80 g/l. The majority of these microorganisms were inhibited by 80 and 40 g/l of the crude extracts. The petroleum ether fraction of Origanum majorana significantly inhibited 94% of the tested strains. Ethyl acetate extracts of all selected plants exhibited relatively low MICs and could be therefore described as strong antibacterial.

  4. Antibacterial activity of alimentary plants against Staphylococcus aureus growth.

    Science.gov (United States)

    Pérez, C; Anesini, C

    1994-01-01

    Alimentary plants were screened for antibacterial activity against a penicillin G resistant strain of Staphylococcus aureus. Twenty-five samples of plant material corresponding to 21 species from 13 families were used. Both aqueous and ethanol extracts were obtained from them. Antibacterial activity was determined by the agar-well diffusion method, using cephazolin as a standard antibiotic. Seventeen ethanol extracts were found active. Eugenia caryophyllata (clavo de olor*) flowers, Myristica fragans (nuez moscada*) seeds, Theobroma cacao (cacao*) seed bark, Triticum sp (trigo*) fruit, Zea mays (maíz*) fruit and Piper nigrum (pimienta*) ripe fruit produced some of the more active extracts (* = Argentine vulgar names).

  5. Antibacterial Activity of Germacrane Type Sesquiterpenes from Curcuma heyneana Rhizomes

    Directory of Open Access Journals (Sweden)

    Hartiwi Diastuti

    2014-03-01

    Full Text Available The isolation of terpenoids from C. heyneana rhizomes and their antibacterial activity have been conducted. The terpenoids were isolated by using vacuum liquid chromatography and radial chromatography. The structures of the compounds were determined based on spectroscopic data (1H-NMR, 13C-NMR (1D and 2D. The antibacterial activity was carried out by using microdilution method and evaluated against eight bacteria. Three germacrane type sesquiterpenes have been isolated from C. heyneana rhizhomes and were identified as germacrone, dehydrocurdione, and 1(10,4(5-diepoxygermacrone. Germacrone showed highest antibacterial activity against P. aeruginosa with MIC values of 15.6 µg/mL and MBC values 31.2 µg/mL. Dehydrocurdione showed highest antibacterial activity against B. subtilis with MIC values of 31.2 µg/mL and MBC values of 31.2 µg/mL. However, 1(10,4(5-diepoxygermacrone showed a weak antibacterial activity.

  6. Antibacterial activity and cytocompatibility of Cu-Ti-O nanotubes.

    Science.gov (United States)

    Hang, Ruiqiang; Gao, Ang; Huang, Xiaobo; Wang, Xiaoguang; Zhang, Xiangyu; Qin, Lin; Tang, Bin

    2014-06-01

    TiO2 nanotubes (NTs) have favorable biological properties, but the poor antibacterial activity limits their application especially in orthopedics fields. In this article, Cu-Ti-O nanotubes with different Cu contents are fabricated on sputtered TiCu films. Scanning electron microscopy reveals the NTs can be formed on sputtered TiCu films when the Cu content is less than 14.6 at %. X-ray photoelectron spectroscopy results indicate the NTs are consist of CuO mixed with TiO2 and the Cu content in NTs decreases dramatically compared with that in TiCu films. Biological experiments show that although these NTs have poor release antibacterial activity, their contact antibacterial activity has proven to be excellent, indicating the NT surface can effectively inhibit biomaterial-associated infections. The cytocompatibility of the NTs is closely related to the Cu content and when its content is relatively low (1.01 at %), there is no appreciable cytotoxicity. So Cu-Ti-O NTs with 1 at % Cu may be suitable to achieve proper antibacterial activity and desired cytocompatibility. The Cu-Ti-O NTs integrate the favorable antibacterial activity of Cu and excellent biological properties of TiO2 NTs therefore have potential applications in orthopedics, dentistry, and other biomedical fields.

  7. Antibacterial activity of Helleborus bocconei Ten. subsp. siculus root extracts.

    Science.gov (United States)

    Puglisi, S; Speciale, A; Acquaviva, R; Ferlito, G; Ragusa, S; De Pasquale, R; Iauk, L

    2009-08-17

    Roots of Helleborus bocconei Ten. subsp. siculus (Schiffner) Merxm. & Podl. are widely used in veterinary folk medicine in Sicily (Italy) to diagnose and cure lower respiratory tract infections in cattle. This study intended to evaluate the in vitro antibacterial activity of the methanolic root extract of Helleborus bocconei Ten. subsp. siculus, and of the bufadienolide and ecdysteroid fractions extracted from its roots, against strains belonging to species commonly associated with respiratory tract infections. The phytochemical screening of the previously prepared plant extracts was carried out by chemical, thin-layer chromatography and spectroscopic methods. The in vitro antibacterial activity of the extracts against seven different standard bacterial strains was evaluated by broth microdilution. According to the present study, Helleborus bocconei Ten. subsp. siculus roots contain bufadienolides and ecdysteroids, and the extracts containing these compounds, as well as the crude methanolic root extract, show antibacterial activity against microorganisms responsible for respiratory infections. In particular, the bufadienolide extract has the highest inhibitory activity against all the tested organisms, and, as the other extracts, shows the lowest MIC values (100mug/ml) against Moraxella catarrhalis and Streptococcus pneumoniae. Since the roots of Helleborus bocconei Ten. subsp. siculus contain substances with antibacterial activity, the traditional use of this plant may also derive from its antibacterial properties.

  8. Structure-activity study of the antibacterial peptide fallaxin

    DEFF Research Database (Denmark)

    Søndergaard, Sandra Lerche; Frimodt-Møller, Niels; Kragelund, Birthe Brandt

    2007-01-01

    , and Pseudomonas aeruginosa. Here, we report a structure-activity study of fallaxin based on 65 analogs, including a complete alanine scan and a full set of N- and C-terminal truncated analogs. The fallaxin analogs were tested for hemolytic activity and antibacterial activity against methicillin...... and inactive analogs according to mean hydrophobicity H and mean hydrophobic moment µH . Far-UV CD-spectroscopy experiments on fallaxin and several analogs in buffer, in TFE, and in membrane mimetic environments (small unilamellar vesicles) indicated that a coiled-coil conformation could be an important...... structural trait for antibacterial activity. This study provides data that support fallaxin analogs as promising lead structures in the development of new antibacterial agents....

  9. Antibacterial activity of ciprofloxacin-loaded zein microsphere films

    Energy Technology Data Exchange (ETDEWEB)

    Fu Jianxi [Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032 (China); Henan Normal University, 46 East Construction Road, Xinxiang, Henan 453007 (China); Wang Huajie [College of Life Science and Biotechnology, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030 (China); Zhou Yanqing [Henan Normal University, 46 East Construction Road, Xinxiang, Henan 453007 (China); Wang Jinye, E-mail: jywang@mail.sioc.ac.cn [Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032 (China); College of Life Science and Biotechnology, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030 (China)

    2009-05-05

    Our aim was to produce an antibiotic-emitting coating composed of zein microspheres for the prevention of bacterial infection on implanted devices. Ciprofloxacin-loaded zein microspheres were prepared using a phase separation procedure, with particle sizes between 0.5 and 2 {mu}m. Drug encapsulation and drug loading varied with the amount of both zein and ciprofloxacin, and the highest encapsulation efficiency was 8.27% (2 mg/ml ciprofloxacin and 20 mg/ml zein; n = 3). A ciprofloxacin-loaded zein microsphere film (CF-MS film) was generated via solvent evaporation. Continuous drug release from a trypsin-degraded microsphere film was observed for up to 28 days. The liberation of ciprofloxacin from the trypsin-degraded film and the biodegradation of the microsphere film were highly correlated. Proliferation assay of the growth of human umbilical vein endothelial cells (HUVECs) by the MTT method showed that the microsphere film had no toxicity when compared with cells grown on Corning culture plates alone and plates with a zein film alone. Quantification of bacteria adhesion showed that adhesion on the microsphere film is significantly suppressed. In addition, according to the results of bacterial growth tests, ciprofloxacin-loaded microsphere films maintained antibacterial activity for more than 6 days. In contrast, a control medium containing a zein film allowed constant bacterial growth. These results indicate that CF-MS films might be useful as antibacterial films on implanted devices.

  10. Acylated flavonol glycosides from Tagetes minuta with antibacterial activity

    Directory of Open Access Journals (Sweden)

    Irum eShahzadi

    2015-09-01

    Full Text Available Wild marigold (Tagetes minuta, a flowering plant of the family Asteraceae contains compounds of pharmaceutical and nutritional importance especially essential oils and flavonols. Identification, characterization of flavonols and determination of their antibacterial activity were major objectives of the current study. The isolation and purification of flavonols was accomplished using chromatographic techniques while structural elucidation was completed by LC-MS and NMR spectroscopy. The extracts and purified compounds were tested against various bacterial strains for antibacterial activity. A total of nineteen flavonols were isolated from this species. Of these, seventeen were of butanol and two of ethyl acetate extracts. Based on the concentration and purity, eight potential flavonols were selected and structurally elucidated. Four flavonols, 6-hydroxyquercetin 7-O-β-(6''-galloylglucopyranoside (2, 6-hydroxykaempferol 7-O-β-glucopyranoside (5, 6-hydroxykaempferol 7-O-β-(6''-galloylglucopyranoside (7, 6-hydroxyquercetin 7-O-β-(6''-caffeoylglucopyranoside (9, were identified for the first time from T. minuta. Butanol and ethyl acetate extracts of flowers and seeds showed significant antibacterial activity against Micrococcus leteus, Staphylococcus aureus, Bacillus subtilis and Pseudomonas piket. Among the isolated flavonols only 1, 2 and 18 were found to possess significant antibacterial activity against M. luteus. The extracts and purified flavonols from T. minuta can be potential candidates for antibacterial drug discovery and support to ethnopharmacological use.

  11. Antibacterial activity of ethanolic extracts of some Vietnamese medicinal plants against Helicobacter pylori

    Science.gov (United States)

    Ngan, Luong Thi My; Dung, Pham Phuong; Nhi, Nguyen Vang Thi Yen; Hoang, Nguyen van Minh; Hieu, Tran Trung

    2017-09-01

    Helicobacter pylori is one of the most common human infectious bacteria. The infection is highly associated with a number of the most important disease of the upper gastrointestinal tract, including gastritis, duodenitis, peptic ulceration, and gastric cancer. In addition, widespread use of antimicrobial agents has resulted in the development of antibiotic resistance. Metabolites of plants, particularly higher plants, have been suggested as alternative potential sources for antibacterial products due to their safe. This study aimed to evaluate antibacterial activities of crude ethanolic extracts of seventeen Vietnamese medicinal plants toward one reference strain and three clinical isolates of Helicobacter pylori using broth micro-dilution bioassay. The antibacterial activities of these extracts were also compared with those of seven antibiotics, amoxicillin, clarithromycin, erythromycin, levofloxacin, azithromycin, tetracycline, and metronidazole. The extracts of Ampelopsis cantoniensis and Cleistocalyx operculatus showed highest antibacterial activity with MIC (MBC) values of 0.31 - 0.97 (2.5 - 5) mg/mL, followed by the extracts of Hedyotis diffusa and Ardisia silvestris with MIC (MBC) values of 1.04 - 1.94 (7.5 - 10) mg/mL. The remaining plant extracts exhibited moderate, low and very low or no active to the H. pylori strains. Further studies are needed to determine the active compounds from the extracts that showed high antibacterial activity against H. pylori.

  12. Developing of a novel antibacterial agent by functionalization of graphene oxide with guanidine polymer with enhanced antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ping [College of Chemistry, Jilin University and MacDiarmid Laboratory, Changchun 130021 (China); Sun, Shiyu [Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun 130012 (China); Dong, Alideertu [College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021 (China); Hao, Yanping; Shi, Shuangqiang; Sun, Zijia [College of Chemistry, Jilin University and MacDiarmid Laboratory, Changchun 130021 (China); Gao, Ge, E-mail: gaoge@jlu.edu.cn [College of Chemistry, Jilin University and MacDiarmid Laboratory, Changchun 130021 (China); Chen, Yuxin, E-mail: chen_yuxin@jlu.edu.cn [Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, Jilin University, Changchun 130012 (China)

    2015-11-15

    Graphical abstract: - Highlights: • A novel antibacterial material, polyethylene glycol (PEG) and polyhexamethylene guanidine hydrochloride (PHGC) dual-polymer-functionalized graphene oxide (GO) (GO-PEG-PHGC), was synthesized. • GO-PEG-PHGC had excellent antibacterial activity against E. coli and S. aureus. • GO-PEG-PHGC shows enhanced antibacterial activity when compared to GO, GO-PEG or GO-PHGC alone, which was described to be related to a better dispersion of GO-PEG-PHGC in the presence of PEG. - Abstract: New materials with excellent antibacterial activity attract numerous research interests. Herein, a facile synthetic method of polyethylene glycol (PEG) and polyhexamethylene guanidine hydrochloride (PHGC) dual-polymer-functionalized graphene oxide (GO) (GO-PEG-PHGC), a novel antibacterial material, was reported. The as-prepared products were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), X-ray pattern (XRD) and elemental analysis. The antibacterial effect on the bacterial strain was investigated by incubating both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). The results show that GO-PEG-PHGC has enhanced antibacterial activity when compared to GO, GO-PEG or GO-PHGC alone. The improved antibacterial activity was described to be related to a better dispersion of GO-PEG-PHGC in the presence of PEG. This better dispersion leads to a greater contact between the bacteria membrane and nanomaterials, therefore leading to greater cell damage. Not only Gram-negative bacteria but also Gram-positive bacteria are greatly inhibited by this antibacterial agent. With the powerful antibacterial activity as well as its low cost and facile preparation, the GO-PEG-PHGC as a novel antibacterial agent can find potential application in the areas of healthcare and environmental engineering.

  13. Antibacterial activities of extracts from twelve Centaurea species from Turkey

    Directory of Open Access Journals (Sweden)

    Tekeli Yener

    2011-01-01

    Full Text Available Members of the genus Centaurea (Asteraceae have been used in traditional plant-based medicine. The methanol extracts of twelve Centaurea species, of which five are endemic to Turkey flora, were screened for antibacterial activity against four bacteria (Escherichia coli, Bacillus cereus, Salmonella enteritidis, Staphylococcus aureus. The antibacterial activity was evaluated by the microdilution method and the minimum inhibition concentrations (MIC of the extracts were determined. C. cariensis subsp. microlepis exhibited an antimicrobial effect on all tested microorganisms. The extracts from eight Centaurea species (C. balsamita, C. calolepis, C. cariensis subsp. maculiceps, C. cariensis subsp. microlepis, C. kotschyi var. kotschyi, C. solstitialis subsp. solstitialis, C. urvillei subsp. urvillei and C. virgata possessed antibacterial activity against several of the tested microorganisms.

  14. Antibacterial and antioxidant activities of Licania tomentosa (Benth. fritsch (crhysobalanaceae

    Directory of Open Access Journals (Sweden)

    Silva J.B.N.F.

    2012-01-01

    Full Text Available This work describes the chemical composition, and evaluates the antimicrobial and antioxidant activities of a hydroalcoholic extract from the leaves of the Licania tomentosa. Gram positive and negative bacterial strains were used in this work. Examination of the phytochemical composition of L. tomentosa revealed the presence of secondary metabolites such as tannins, flavonoids, saponins, alkaloids, steroids and triterpenoids. An antibacterial assay pointed out that the extract had a lower minimal inhibitory concentration (MIC - 32 μg/mL towards Staphylococcus aureus (ATCC12692. The extract also presented antibacterial activity against other assayed bacteria, with the MIC varying between 64 and 512 μg/ mL. Our findings reveal that the extract presented an antioxidative capacity lower than that of BHT at the same concentration, used as positive control. Our results suggest that the levels and combinations between the secondary metabolites of this plant should be investigated to explain the demonstrated antibacterial activity.

  15. Antibacterial activity of ifve Peruvian medicinal plants against Pseudomonas aeruginosa

    Institute of Scientific and Technical Information of China (English)

    Gabriela Ulloa-Urizar; Miguel Angel Aguilar-Luis; Mara del Carmen De Lama-Odra; Jos Camarena-Lizarzaburu; Juana del Valle Mendoza

    2015-01-01

    Objective:To evaluate the susceptibility of Pseudomonas aeruginosa (P. aeruginosa) in vitro to the ethanolic extracts obtained from five different Peruvian medicinal plants. Methods:The plants were chopped and soaked in absolute ethanol (1:2, w/v). The antibacterial activity of compounds against P. aeruginosa was evaluated using the cup-plate agar diffusion method. Results:The extracts from Maytenus macrocarpa (“Chuchuhuasi”), Dracontium loretense Krause (“Jergon Sacha”), Tabebuia impetiginosa (“Tahuari”), Eucalyptus camaldulensis Dehn (eucalyptus), Uncaria tomentosa (“Uña de gato”) exhibited favorable antibacterial activity against P. aeruginosa. The inhibitory effect of the extracts on the strains of P. aeruginosa tested demonstrated that Tabebuia impetiginosa and Maytenus macrocarpa possess higher antibacterial activity. Conclusions:The results of the present study scientifically validate the inhibitory capacity of the five medicinal plants attributed by their common use in folk medicine and contribute towards the development of new treatment options based on natural products.

  16. Antibacterial activity of five Peruvian medicinal plants against Pseudomonas aeruginosa

    Institute of Scientific and Technical Information of China (English)

    Gabriela; Ulloa-Urizar; Miguel; Angel; Aguilar-Luis; María; del; Carmen; De; Lama-Odría; José; Camarena-Lizarzaburu; Juana; del; Valle; Mendoza

    2015-01-01

    Objective: To evaluate the susceptibility of Pseudomonas aeruginosa(P. aeruginosa)in vitro to the ethanolic extracts obtained from five different Peruvian medicinal plants.Methods: The plants were chopped and soaked in absolute ethanol(1:2, w/v). The antibacterial activity of compounds against P. aeruginosa was evaluated using the cupplate agar diffusion method.Results: The extracts from Maytenus macrocarpa("Chuchuhuasi"), Dracontium loretense Krause("Jergon Sacha"), Tabebuia impetiginosa("Tahuari"), Eucalyptus camaldulensis Dehn(eucalyptus), Uncaria tomentosa("U?a de gato") exhibited favorable antibacterial activity against P. aeruginosa. The inhibitory effect of the extracts on the strains of P. aeruginosa tested demonstrated that Tabebuia impetiginosa and Maytenus macrocarpa possess higher antibacterial activity.Conclusions: The results of the present study scientifically validate the inhibitory capacity of the five medicinal plants attributed by their common use in folk medicine and contribute towards the development of new treatment options based on natural products.

  17. Antibacterial activity of graphene supported FeAg bimetallic nanocomposites.

    Science.gov (United States)

    Ahmad, Ayyaz; Qureshi, Abdul Sattar; Li, Li; Bao, Jie; Jia, Xin; Xu, Yisheng; Guo, Xuhong

    2016-07-01

    We report the simple one pot synthesis of iron-silver (FeAg) bimetallic nanoparticles with different compositions on graphene support. The nanoparticles are well dispersed on the graphene sheet as revealed by the TEM, XRD, and Raman spectra. The antibacterial activity of graphene-FeAg nanocomposite (NC) towards Bacillus subtilis, Escherichia coli, and Staphylococcus aureus was investigated by colony counting method. Graphene-FeAg NC demonstrates excellent antibacterial activity as compared to FeAg bimetallic without graphene. To understand the antibacterial mechanism of the NC, oxidative stress caused by reactive oxygen species (ROS) and the glutathione (GSH) oxidation were investigated in the system. It has been observed that ROS production and GSH oxidation are concentration dependent while the increase in silver content up to 50% generally enhances the ROS production while ROS decreases on further increase in silver content. Graphene loaded FeAg NC demonstrates higher GSH oxidation capacity than bare FeAg bimetallic nanocomposite. The mechanism study suggests that the antibacterial activity is probably due to membrane and oxidative stress produced by the nanocomposites. The possible antibacterial pathway mainly includes the non-ROS oxidative stress (GSH oxidation) while ROS play minor role.

  18. Effects of fractionation on antibacterial activity of crude extracts of ...

    African Journals Online (AJOL)

    Jane

    2010-10-18

    Oct 18, 2010 ... TiA showed activity against 100% of the test gram negative bacterial strains and 60% of the ... Key words: Fractionation, chromatography, plant extract, Tamarindus indica, antibacterial activity, .... The phytochemical analysis showed that TiA, .... Alleviating Soil Acidity through Plant Organic Compounds. Braz ...

  19. Synthesis and Antibacterial Activity of New Cephalosporin Compounds

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Five new cephalosporin compounds were designed and synthesized, and the antibacterial activities were evaluated by the standard serial 2-fold agar dilution method in vitro.The results showed that the activities of the compounds Ⅰa and Ⅰb against ESBL E. coli and K.pneumoniae are comparable to those of Cefepime.

  20. Antibacterial activity of various leaf extracts of Merremia emarginata

    Institute of Scientific and Technical Information of China (English)

    EK Elumalai; M Ramachandran; T Thirumalai; P Vinothkumar

    2011-01-01

    Objective: To investigate the antibacterial activity and phytochemical screening of the aqueous, methanol and petroleum ether leaf extracts of Merremia emarginata (M. emarginata). Methods:The antibacterial activity of leaf extracts of M. emarginata were evaluated by agar well diffusion method against four selected bacterial species. Results: The presence of tannins, flavonoids, amino acids, starch, glycosides and carbohydrates in the different leaf extracts was established. The methanol extract was more effective against Bacillus cereus and Escherichia coli, whereas aqueous extract was more effective against Staphylococcus aureus and Pseudomonas aeruginosa.Conclusions: The results in the present study suggest that M. emarginata leaf can be used in treating diseases caused by the tested organisms.

  1. Synthesis and antibacterial activity of new chiral -sulfamoyloxazolidin-2-ones

    Indian Academy of Sciences (India)

    Fouzia Bouchareb; Malika Berredjem; Samira Ait Kaki; Amel Bouaricha; Abdeslem Bouzina; Billel Belhani; Nour-Eddine Aouf

    2016-01-01

    A new series of , ′-bis-oxazolidinones-sulfone and 5-chloromethylsulfamoyl-oxazolidin-2-ones have been synthesized in three steps (carbamoylation, sulfamoylation and cyclization) starting from 1,3-dichloroporopan-2-ol, chlorosulfonyl isocyanate and primary or secondary amines. Synthesis has been carried out following simple methodology in excellent isolated yields. The structure and purity of the original compounds were confirmed by IR, NMR, and MS. The compounds were evaluated for their in vitro antibacterial activity against some Gram-positive bacteria; Staphylococcus aureus and Gram-negative bacteria; Escherichia Coli, Klebsiella pneumonieae, Acinetobacter, Pseudomonas aeruginosa, Enterococcus, Salmonella sp. The compounds showed moderate to good antibacterial activity.

  2. Antibacterial activity of silver bionanocomposites synthesized by chemical reduction route

    Directory of Open Access Journals (Sweden)

    Bin Ahmad Mansor

    2012-09-01

    Full Text Available Abstract Background The aim of this study is to investigate the functions of polymers and size of nanoparticles on the antibacterial activity of silver bionanocomposites (Ag BNCs. In this research, silver nanoparticles (Ag NPs were incorporated into biodegradable polymers that are chitosan, gelatin and both polymers via chemical reduction method in solvent in order to produce Ag BNCs. Silver nitrate and sodium borohydride were employed as a metal precursor and reducing agent respectively. On the other hand, chitosan and gelatin were added as a polymeric matrix and stabilizer. The antibacterial activity of different sizes of silver nanoparticles was investigated against Gram-positive and Gram-negative bacteria by the disk diffusion method using Mueller-Hinton Agar. Results The properties of Ag BNCs were studied as a function of the polymer weight ratio in relation to the use of chitosan and gelatin. The morphology of the Ag BNCs films and the distribution of the Ag NPs were also characterized. The diameters of the Ag NPs were measured and their size is less than 20 nm. The antibacterial trait of silver/chitosan/gelatin bionanocomposites was investigated. The silver ions released from the Ag BNCs and their antibacterial activities were scrutinized. The antibacterial activities of the Ag BNC films were examined against Gram-negative bacteria (E. coli and P. aeruginosa and Gram-positive (S. aureus and M. luteus by diffusion method using Muller-Hinton agar. Conclusions The antibacterial activity of Ag NPs with size less than 20 nm was demonstrated and showed positive results against Gram-negative and Gram-positive bacteria. The Ag NPs stabilized well in the polymers matrix.

  3. Antibacterial Activity of Cetyltrimethylammonium Bromide Modified Silver-Bentonite

    Directory of Open Access Journals (Sweden)

    Nik Malek Nik Ahmad Nizam

    2016-01-01

    Full Text Available Organo-Ag-bentonite was prepared by the attachment of cationic surfactant cetyltrimethylammonium bromide on silver(Ag-exchanged bentonite. The prepared samples were characterized by X-ray diffraction (XRD, Fourier transform infrared (FTIR spectroscopy and energy dispersive X-ray (EDX analysis and antibacterial assay was performed against Escherichia coli in different percentage of saline solutions through minimum inhibition concentration (MIC method. Organo-Ag-bentonite showed higher antibacterial activity than organo-bentonite and Ag-bentonite especially in saline solution suggesting that the precipitation of AgCl in the presence of Ag-bentonite in saline solution could be avoided by the attachment of cationic surfactant on Ag-bentonite surfaces, hence increased their antibacterial activity.

  4. Evaluation of Benzophenone-N-ethyl Morpholine Ethers as Antibacterial and Antifungal Activities

    Directory of Open Access Journals (Sweden)

    A. Bushra Begum

    2014-01-01

    Full Text Available Microorganisms are closely associated with the health and welfare of human beings. Whereas some microorganisms are beneficial, others are detrimental. Bacterial infections often produce inflammation and pains and in some instances, infections result in high mortality. Any subtle change in the drug molecule, which may not be detected by chemical methods, can be revealed by a change in the antimicrobial activity and hence microbiological assays are very useful. A series of substituted hydroxy benzophenones and benzophenone-N-ethyl morpholine ethers were screened for their antibacterial and antifungal activities. Antibacterial activity against S. aureus, E. aerogenes, M. luteus, K. pneumonia, and S. typhimurium, S. paratyphi-B and P. vulgaris bacterial strains and antifungal activity against C. albicans, B. cinerea, M. pachydermatis, C. krusei fungal strains were carried out. The bioassays indicated that most of the synthesized compounds showed potential antibacterial and antifungal agents.

  5. Antibacterial Characteristics and Activity of Water-Soluble Chitosan Derivatives Prepared by the Maillard Reaction

    Directory of Open Access Journals (Sweden)

    Ying-Chien Chung

    2011-10-01

    Full Text Available The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. In addition, it was found that the susceptibility of the test organisms to the water-soluble chitosan derivative was higher in deionized water than in saline solution. Metal ions were also found to reduce the antibacterial activity of the water-soluble chitosan derivative on S. aureus. The marked increase in glucose level, protein content and lactate dehydrogenase (LDH activity was observed in the cell supernatant of S. aureus exposed to the water-soluble chitosan derivative in deionized water. The results suggest that the water-soluble chitosan produced by Maillard reaction may be a promising commercial substitute for acid-soluble chitosan.

  6. Antibacterial Activity and Toxicity of Analogs of Scorpion Venom IsCT Peptides.

    Science.gov (United States)

    de la Salud Bea, Roberto; Petraglia, Adam F; Ascuitto, Michael R; Buck, Quentin M

    2017-06-28

    Seven analogs of the natural, α-helix peptides IsCT1 and IsCT2-found in the venom of scorpion Opithancatus Madagascariensis-have been synthesized and tested to compare their antibacterial and hemolytic activity against natural peptides. In general, results show that increasing hydrophobicity by substituting positions 5 and 9 of the sequences with alanine, valine, and leucine, enhances antibacterial activity. However, this also increases hemolytic activity. The analog with an increased net positive charge from +1 to +3 produces moderate bacterial growth inhibition but also has high hemolytic activity. On the other hand, the analog with a negative net charge (-1) has low antibacterial properties but also no cytotoxicity under the tested conditions, a similar result was found for five of the seven studied analogs.

  7. Potential Anti-cancer and Anti-bacterial Activities of Philippine Echinoderm Extracts

    Directory of Open Access Journals (Sweden)

    Rodyl J. Layson

    2014-11-01

    Full Text Available In high-throughput search for bioactive compounds under resource-limited settings from Philippine echinoderms, the aqueous, methanol, chloroform and hexane extracts of seven Philippine echinoderms namely Holothuria nobilis (sea cucumber, Bohadscia marmorata (sea cucumber, Stichopus chloronatus (sea cucumber, Holothuria axiologa (sea cucumber, Linckia laevigata (starfish, Oreaster nodusus (starfish and Ophiocoma ochoenleinii (brittle star were screened for antitumor and antibacterial activity. Antitumor activity was determined using brine shrimp lethality assay while antibacterial assay was performed using turbidimetric method. Both assays utilized 96-well microtiter plates to facilitate speed and ease in screening. The chloroform extract of H. nobilis gave a positive result on antitumor activity while almost all sample extracts showed antibacterial activity against E. coli.

  8. Superior antibacterial activity of nanoemulsion of Thymus daenensis essential oil against E. coli.

    Science.gov (United States)

    Moghimi, Roya; Ghaderi, Lida; Rafati, Hasan; Aliahmadi, Atousa; McClements, David Julian

    2016-03-01

    Natural preservatives are being extensively investigated for their potential industrial applications in foods and other products. In this work, an essential oil (Thymus daenensis) was formulated as a water-dispersible nanoemulsion (diameter=143nm) using high-intensity ultrasound. The antibacterial activity of the essential oil in both pure and nanoemulsion forms was measured against an important food-borne pathogen bacterium, Escherichia coli. Antibacterial activity was determined by measuring the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The antibacterial activity of the essential oil against E. coli was enhanced considerably when it was converted into a nanoemulsion, which was attributed to easier access of the essential oils to the bacterial cells. The mechanism of antibacterial activity was investigated by measuring potassium, protein, and nucleic acid leakage from the cells, and electron microscopy. Evaluation of the kinetics of microbial deactivation showed that the nanoemulsion killed all the bacteria in about 5min, whereas only a 1-log reduction was observed for pure essential oil. The nanoemulsion appeared to amplify the antibacterial activity of essential oils against E. coli by increasing their ability to disrupt cell membrane integrity.

  9. Comparative analysis of antibacterial activity of povidone iodine and homoeopathic mother tinctures as antiseptics

    Directory of Open Access Journals (Sweden)

    Muhammad Mohsin Zaman

    2016-01-01

    Conclusion: This study confirms the antibacterial activity and more effectiveness of Thuja occidentalis and Rhus glabra mother tinctures than povidone iodine. The other tested mother tinctures also have antibacterial activity against tested bacteria, except Echinacea.

  10. In vitro antibacterial activity of some plant essential oils

    Directory of Open Access Journals (Sweden)

    Ignacimuthu Savarimuthu

    2006-11-01

    Full Text Available Abstract Background: To evaluate the antibacterial activity of 21 plant essential oils against six bacterial species. Methods: The selected essential oils were screened against four gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris and two gram-positive bacteria Bacillus subtilis and Staphylococcus aureus at four different concentrations (1:1, 1:5, 1:10 and 1:20 using disc diffusion method. The MIC of the active essential oils were tested using two fold agar dilution method at concentrations ranging from 0.2 to 25.6 mg/ml. Results: Out of 21 essential oils tested, 19 oils showed antibacterial activity against one or more strains. Cinnamon, clove, geranium, lemon, lime, orange and rosemary oils exhibited significant inhibitory effect. Cinnamon oil showed promising inhibitory activity even at low concentration, whereas aniseed, eucalyptus and camphor oils were least active against the tested bacteria. In general, B. subtilis was the most susceptible. On the other hand, K. pneumoniae exhibited low degree of sensitivity. Conclusion: Majority of the oils showed antibacterial activity against the tested strains. However Cinnamon, clove and lime oils were found to be inhibiting both gram-positive and gram-negative bacteria. Cinnamon oil can be a good source of antibacterial agents.

  11. Antibacterial activity of some actinomycetes from Tamil Nadu, India

    Institute of Scientific and Technical Information of China (English)

    Pachaiyappan Saravana Kumar; John Poonga Preetam Raj; Veeramuthu Duraipandiyan; Savarimuthu Ignacimuthu

    2012-01-01

    Objective:To isolate novel actinomycetes and to evaluate their antibacterial activity. Methods:Three soil samples were collected from Vengodu (village) in Kanchipuram district, Tamil Nadu, India. Actinomycetes were isolated using serial dilution and plating method on actinomycetes isolation agar. Results: Totally 35 isolates were obtained on the basis of colony characteristics on actinomycetes isolation agar. All the isolates were screened for antibacterial activity by cross streak method. Medium and optimization of day were done for the potent strains using Nathan's agar well diffusion method. Isolation of bioactive compounds from significant active isolates was done by using different media. The most active isolate VAS 10 was identified as Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) using 16s rRNA sequence method. The hexane, ethyl acetate, dichloromethane and butanol extracts of VAS 10 were tested against bacteria. The maximum antibacterial activity was observed in dichloromethane and ethyl acetate;maximum zones of inhibition were observed against Enterococcus durans. The rRNA secondary structure and the restriction sites of Actinobacterium Loyola VAS 10 were predicted using Genebee and NEBCutter online tools respectively. Conclusions: The present study showed that among the isolated actinomycetes, Actinobacterium Loyola PBT VAS 10 (accession No. JF501398) showed good antibacterial activity against the tested bacteria.

  12. Antibacterial activity of four Gracilaria species of red seaweeds collected from Mandapam Coast, Gulf of Mannar Marine Biosphere Reserve, India

    Directory of Open Access Journals (Sweden)

    Sethu Rameshkumar

    2016-09-01

    Full Text Available Objective: To study the antibacterial activities of diethyl ether, toluene, ethanol and methanol extracts of red seaweeds such as Gracilaria crassa (G. crassa, Gracilaria folifera (G. folifera, Gracilaria debilis (G. debilis and Gracilaria corticata. Methods: The crude extracts were tested against different types of Gram-positive and -negative bacterial strains and all the seaweed extracts were tested a broad spectrum of antibacterial activity. Antibacterial activity was made using paper disc diffusion method. Four organic solvents (diethyl ether, toluene, methanol and ethanol were used separately in a Soxhlet apparatus for seven bacterial strains. Antibacterial activity of the known antibiotics such as chloramphenicol, streptomycin, kanamycin and ampicillin was determined by testing them against different test organisms. Results: The high antibacterial activity was noted in the extracts of G. crassa, G. folifera and G. debilis. However, G. crassa and G. debilis have good antibacterial activity. Pathogens like Bacillus subtilis and Escherichia coli were less susceptible to the methanol and diethyl ether extracts of G. folifera. The comparative study on the antibacterial activity was also made by using 200 μg concentration of solvent extracts (diethyl ether, ethanol, toluene and methanoland different five antibiotics such as chloramphenicol, streptomycin, kanamycin, amoxicillin and ampicillin. The bacterial strains tested were more sensitive to chloramphenicol, streptomycin, kanamycin, and ampicillin when compared to algal extracts. Conclusions: The present study proved that the extracts of G. crassa, G. folifera and G. debilis have high antibacterial activity. Although G. crassa and G. debilis showed good antibacterial activity, many known antibiotics are active against a few organisms individually. Hence, the extracts of seaweeds were active against all test organisms used and the activities were comparable to that of antibiotics and the

  13. Synthesis and antibacterial activity of pleuromutilin derivatives with novel C(14) side chain

    Institute of Scientific and Technical Information of China (English)

    Li Qiang Fu; Chen Yu Ling; Xing Sheng Guo; Hui Li He; Yu She Yang

    2012-01-01

    In order to find novel antibacterial agents with superior antibacterial activity and overcoming multidrug resistance,a series of pleuromutilin derivatives with novel C(14) side chain were synthesized and evaluated for their in vitro antibacterial activities.The results of antibacterial acticities indicated that most of the derivatives showed potent activities against Gram-positive organisms.In particular,compound 10d exhibited the most potent inhibitory activity compared with pleuromutilin and linezoid,emerged as potential molecule for further investigation.

  14. Imidazoles as promising scaffolds for antibacterial activity: a review.

    Science.gov (United States)

    Rani, Nidhi; Sharma, Ajay; Singh, Randhir

    2013-10-01

    In the last few decades, a lot of work has been done on heterocycles, especially the imidazole ring, to obtain a scaffold with potential pharmacological properties such as antibacterial, antifungal, anticancer, antiviral, antidiabetic and others, with lesser side effects. The search for new biologically active imidazoles continues to be an interesting area of investigation in medicinal chemistry. The present paper aims to bring together and discuss the wealth of information on antibacterial profile of imidazoles. So it can be employed for future development to obtain new potent drug molecules.

  15. Antibacterial activity of N-halamine decorated mesoporous silica nanoparticles

    Science.gov (United States)

    Xu, Jiarong; Zhang, Yu; Zhao, Yanbao; Zou, Xueyan

    2017-09-01

    N-halamine decorated mesoporous silica nanoparticles (mSiO2/halamine NPs) were prepared by coating mSiO2 NPs with poly (1-allylhydantoin-co-methyl methacrylate) (AH-co-MMA) by the aid of the radical polymerization, followed by chlorination treatment. The sterilizing effect on the bacterial strain is investigated by incubating Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Results indicated that the mSiO2/halamine NPs had excellent antibacterial activity and no significant change occurred in antibacterial efficiency after five recycle experiments.

  16. Functional Iron Oxide-Silver Hetero-Nanocomposites: Controlled Synthesis and Antibacterial Activity

    Science.gov (United States)

    Trang, Vu Thi; Tam, Le Thi; Van Quy, Nguyen; Huy, Tran Quang; Thuy, Nguyen Thanh; Tri, Doan Quang; Cuong, Nguyen Duy; Tuan, Pham Anh; Van Tuan, Hoang; Le, Anh-Tuan; Phan, Vu Ngoc

    2017-02-01

    Iron oxide-silver nanocomposites are of great interest for their antibacterial and antifungal activities. We report a two-step synthesis of functional magnetic hetero-nanocomposites of iron oxide nanoparticles and silver nanoparticles (Fe3O4-Ag). Iron oxide nanoparticles were prepared first by a co-precipitation method followed by the deposition of silver nanoparticles via a hydrothermal route. The prepared Fe3O4-Ag hetero-nanocomposites were characterized by x-ray diffraction, transmission electron microscopy, high resolution transmission electron microscopy and vibrating sample magnetometry. Their antibacterial activities were investigated by using paper-disc diffusion and direct-drop diffusion methods. The results indicate that the Fe3O4-Ag hetero-nanocomposites exhibit excellent antibacterial activities against two Gram-negative bacterial strains (Salmonella enteritidis and Klebsiella pneumoniae).

  17. Determination of reactive oxygen generated from natural medicines and their antibacterial activity$

    Institute of Scientific and Technical Information of China (English)

    Noriko Tajima; Makiko Takasaki; Haruka Fukamachi; Takeshi Igarashi; Yoshijiro Nakajima; Hidetoshi Arakawa

    2016-01-01

    Extracts of 16 natural medicine powders (Galla chinensis, Malloti cortex, Cassiae semen, Sophorae radix, Myricae cortex, Crataegi fructus, Gambir, Mume fructus, Geranii herba, Phellodendri cortex, Coptidis rhizoma, Swertiae herba, and Cinnamomi cortex) were assayed for reactive oxygen concentrations using the per-oxyoxalate chemiluminescent detection system. High luminescence intensity was observed in Galla chinensis, Geranii herba, Malloti cortex, Myricae cortex, and Cinnamomi cortex. Additional experiments identified the reactive oxygen species as hydrogen peroxide. Galla chinensis generated 2.4 ? 10 ? 4 mol/L hydrogen peroxide from a 1 mg/mL solution. In bacterial growth tests, Galla chinensis extract had antibacterial activity against Escherichia coli, Staphylococcus aureus, Bacteroides thetaiotaomicron, Campylobacter sputorum biovar sputorum, Streptococcus salivarius thermophilus, Lactobacillus casei, and Bifidobacterium longum infantis. This antibacterial activity was de-creased by the addition of catalase. It revealed that hydrogen peroxide which Galla chinensis produced participated in antibacterial activity.

  18. Antimutagenic and antibacterial activities of Peltophorum ferrugineum flower extracts

    Directory of Open Access Journals (Sweden)

    Rinki Dandapat

    2012-10-01

    Full Text Available Objective: To study the antibacterial and antimutagenic properties of the Peltophorum ferrugineum flower extracts. Methods: Dried flowers of P. ferrugineum were extracted successively with hexane, ethyl acetate, acetone and methanol, and the total phenolic content of extracts were determined spectrophotometrically at 760 nm after reaction with the Folin-Ciocalteu reagent. The extracts were tested against Bacillus cereus, Staphylococcus aureus, Escherichia coli and Yersinia enterocolitica by agar dilution method. The antimutagenicity of extracts was studied using the tester strains of Salmonella typhimurium by the standard plate incorporation test. The effect of extracts on nucleic acid leakage (spectrophotometrically at 260 nm, bacterial respiration (total dissolved oxygen and bacterial cell wall (Scanning Electron Microscopy were also determined. Results: The total phenolic content of extracts was in the order of methanol > acetone > hexane > ethyl acetate. All the extracts showed antibacterial activity with minimum inhibitory concentration (MIC ranging from 0.1 to 1.25%. However, higher activity was found with acetone and methanol extracts. The acetone and methanol extracts showed strong antimutagenic activity against sodium azide and methyl methane sulfonate induced mutation in Salmonella tester strains. The antibacterial action of extracts was probably due to the ability of these extracts to cause the disintegration of cell wall, leakage of genetic material and inhibition of respiration. Conclusions: It can be concluded that the acetone and methanol extracts of P. ferrugineum possess antibacterial and antimutagenic activities, and can find application as food preservatives and nutraceuticals.

  19. Antibacterial activity of essential oils: potential applications in food

    NARCIS (Netherlands)

    Burt, S.A.

    2007-01-01

    Due to its antibacterial activity, oregano oil has lately become interesting as a potential 'natural' food preservative. Oregano oil was found to be a fast acting and effective inhibitor of a strain of Escherichia coli O157:H7, the causative agent of a serious gastro-enteritis, and was lethal to

  20. 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

  1. Antibacterial activity of essential oils: potential applications in food

    NARCIS (Netherlands)

    Burt, S.A.

    2007-01-01

    Due to its antibacterial activity, oregano oil has lately become interesting as a potential 'natural' food preservative. Oregano oil was found to be a fast acting and effective inhibitor of a strain of Escherichia coli O157:H7, the causative agent of a serious gastro-enteritis, and was lethal to thi

  2. Antibacterial activity of polymer coated cerium oxide nanoparticles.

    Directory of Open Access Journals (Sweden)

    Vishal Shah

    Full Text Available Cerium oxide nanoparticles have found numerous applications in the biomedical industry due to their strong antioxidant properties. In the current study, we report the influence of nine different physical and chemical parameters: pH, aeration and, concentrations of MgSO(4, CaCl(2, KCl, natural organic matter, fructose, nanoparticles and Escherichia coli, on the antibacterial activity of dextran coated cerium oxide nanoparticles. A least-squares quadratic regression model was developed to understand the collective influence of the tested parameters on the anti-bacterial activity and subsequently a computer-based, interactive visualization tool was developed. The visualization allows us to elucidate the effect of each of the parameters in combination with other parameters, on the antibacterial activity of nanoparticles. The results indicate that the toxicity of CeO(2 NPs depend on the physical and chemical environment; and in a majority of the possible combinations of the nine parameters, non-lethal to the bacteria. In fact, the cerium oxide nanoparticles can decrease the anti-bacterial activity exerted by magnesium and potassium salts.

  3. Design, synthesis and antibacterial activity of novel 1-oxacephem analogs

    Institute of Scientific and Technical Information of China (English)

    Yi He; Jian Bo Wu; Fan Lei; Pei Chen; Li Hai; Yong Wu

    2012-01-01

    A series of 1-oxacephem analogs were synthesized and their antibacterial properties against five strains of Gram-positive and Gram-negative bacteria were evaluated in vitro while ceftazidine was selected as control.Some of the tested compounds,compound 12c in particular,showed more active against three selected strains than the standard.

  4. A preliminary study on the antibacterial mechanism of Tegillarca granosa hemoglobin by derived peptides and peroxidase activity.

    Science.gov (United States)

    Bao, Yongbo; Wang, Juanjuan; Li, Chenghua; Li, Peifen; Wang, Sufang; Lin, Zhihua

    2016-04-01

    The blood clam, Tegillarca granosa, is one of the few bivalve molluscs containing hemoglobin (Hb). In the present study, we purified two types of T. granosa hemoglobin, Tg-HbI and Tg-HbII, using size exclusion chromatography and measured their antibacterial and peroxidase activities. We also tested antibacterial activities of peptides prepared by trypsin digestion of purified Tg-Hb and reversed-phase high-performance liquid chromatography purification. Purified Tg-HbI and Tg-HbII showed antibacterial activity against Escherichia coli, Pseudomonas putida, Bacillus subtilis, and Bacillus firmus, with differences in minimal inhibitory concentrations (MICs), but lacked antibacterial activity against Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio harveyi and Staphylococcus aureus. In contrast, 7 Tg-Hb derived peptides exhibited varying degrees of antibacterial activity against V. alginolyticus (MICs: 12-200 μg/ml), V. parahaemolyticus (11-100 μg/ml) and V. harveyi (1-200 μg/ml). The antibacterial activity of Hb derived peptides was confirmed by fluorescence microscopy. In addition, peroxidase activity was detected in Tg-HbI and Tg-HbII. The results indicated that in addition to functioning as a respiratory protein T. granosa hemoglobins likely play a role in host antibacterial defense probably via a peroxidase activity of native molecules and some internal peptides released from the proteins.

  5. Loaded Ce-Ag organic-inorganic hybrids and their antibacterial activity.

    Science.gov (United States)

    Truffault, Laurianne; Rodrigues, Danilo Fernando; Salgado, Hérida Regida Nunes; Santilli, Celso Valentim; Pulcinelli, Sandra Helena

    2016-11-01

    There are requirements for surfaces with antibacterial properties in various technological fields. U-PEO hybrids with antibacterial properties were synthesized by the sol-gel process, incorporating combinations of cerium and silver salts at different silver molar fractions (0, 0.02, 0.05, 0.10, and 1) relative to the total amount of doped cations. The loaded hybrids were characterized by TGA, XRD, and Raman spectroscopy. Release tests were performed using UV-vis spectroscopy, and the antibacterial properties of the hybrids were studied in agar tests and turbidimetry assays. The nanostructural evolution of the hybrids during the release of the antibacterial agents was investigated by in situ SAXS. XRD results showed the presence of the AgCl crystalline phase in the loaded hybrids from a silver molar fraction of 0.05. Raman spectroscopy evidenced the interaction of silver cations with the polymeric part of the hybrid. SAXS results confirmed these interactions and showed that cerium species interacted with both organic and inorganic parts of the hybrids. The loaded U-PEO hybrids were found to release all the incorporated cerium in 1h, while the hybrid containing 100% of silver released only 78% of the incorporated silver. All the loaded hybrids displayed antibacterial activity against the Pseudomonas aeruginosa bacterium. The antibacterial activity was found to increase with silver molar fraction. Due to its high antibacterial activity and low silver molar fraction, the loaded hybrid with silver molar fraction of 0.10 seemed to be a good compromise between efficiency, esthetic transparency, and photostability.

  6. Antioxidant, Anticholinesterase and Antibacterial Activities of Jurinea consanguinea DC

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    Hülya Öztürk

    2011-01-01

    Full Text Available The aim of this study was to investigate in vitro antioxidant, anticholinesterase and antibacterial activities of the petroleum ether, chloroform and methanol extracts obtained from the aerial parts of Jurinea consanguinea DC. (Asteraceae. Total phenolic and flavonoid contents of these crude extracts were determined as pyrocatechol and quercetin equivalents, respectively. The methanol extract which possessed almost the same effect with the chloroform extract in b -carotene-linoleic acid system exhibited higher free radical scavenging activity than a standard compound, BHT, at 100 and 200 m g/mL concentrations. The petroleum ether extract showed the highest acetylcholinesterase inhibitory activity among the tested extracts. The methanol extract exhibited higher butyrylcholinesterase inhibitory activity than galantamine at all concentrations (94% inhibition at 200 m g/mL. The antibacterial activity of the extracts was determined by the disc diffusion method. The chloroform extract showed moderate activity against B. subtilis, P. aeruginosa and S. aureus.

  7. In Vitro antibacterial activity of ibuprofen and acetaminophen

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    Ali Abdul Hussein S AL-Janabi

    2010-01-01

    Full Text Available Background: Ibuprofen and acetaminophen are common chemical agents that have anti-inflammatory, antipyretic, and analgesic activity. Aims: To detect any potential antibacterial effects of ibuprofen and acetaminophen on pathogenic bacteria. Materials and methods: Ibuprofen and acetaminophen were tested for antibacterial activity against seven isolates of bacteria including gram positive bacteria (Staphylococci aureus and Bacillus subtilis and gram negative bacteria (E. coli, Enterobacter aerogenes, Enterobacter cloacae, Salmonella typhi and Paracoccus yeei. Spectrophotometer assay was applied to determine the antibacterial activities of ibuprofen and acetaminophen. Three controls were included in this study: Ampicilline sodium (20 μg/ml; cefotaxime sodium (20 μg/ml and chemical free medium. Results: Staphylococcus aureus and Paracoccus yeei were susceptible to lower concentrations of ibuprofen and acetaminophen (MIC=1.25 mg/ml, while two strains of Enterobacter exhibited resistance to these agents. Conclusions: Ibuprofen and acetaminophen showed a potential antibacterial effect on isolated strains of bacteria. They had the same ability to inhibit bacterial growth.

  8. Antibacterial activity of TiO2 nanotubes: Influence of crystal phase, morphology and Ag deposition

    Science.gov (United States)

    Li, Huirong; Cui, Qiang; Feng, Bo; Wang, Jianxin; Lu, Xiong; Weng, Jie

    2013-11-01

    TiO2 nanotubes on Ti substrate were fabricated by electrochemical anodization. Ag nanoparticles were deposited on the TiO2 nanotubes by a silver mirror reaction. Antibacterial activity of the nanotubes with different structural features was evaluated by a culture test with Escherichia coli bacteria. The anatase nanotubes showed the highest antibacterial activity among three crystal phases including anatase, rutile and amorphous titania. The diameters of the nanotubes affected the antibacterial activity. The two nanotubes with 200 nm and 50 nm diameters had higher antibacterial rate than those with other diameters. The antibacterial activity of the nanotubes was independent on their lengths. Ag-deposited nanotubes exhibited excellent antibacterial activity and its antibacterial rate was up to approximately 100%. TiO2 nanotubes and Ag-deposited nanotubes on titanium should be potential for antibacterial applications in clinics and industry, especially regarding with their reusability.

  9. In vitro and in vivo antibacterial activity of Pogostone

    Institute of Scientific and Technical Information of China (English)

    Peng Fu; Wan Feng; Xiong Liang; Peng Cheng; Dai Min; Chen Jianping

    2014-01-01

    Background Our pervious antibacterial studies on several traditional Chinese medicines have found that Patchouli oil from Pogostemon cablin had significant antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA),which has spread worldwide and infected innumerable people.In order to find the more active natural substances in Patchouli oil,one of the major components,Pogostone,was isolated and its antibacterial activity was evaluated in vitro and in vivo in this study.Methods In vitro test,Pogostone was screened for antimicrobial properties against 83 bacteria comprising 35 gram positive and 48 gram negative bacteria strains via the agar double dilution method.In vivo test,specific pathogen free (SPF) strain of both male and female white Kunming mice,weighing 18-22 g,were used to test the protective ability of Pogostone after being injected with the median lethal doses (MLDs) of the tested strains.Results In vitro test,Pogostone could inhibit both gram negative bacteria (0.098-1 600 μg/ml) and gram positive bacteria(0.098-800 μg/ml).For Corynebacterium xerosis and some Chryseobacterium indologenes,the minimum inhibitory concentration (MIC) values of Pogostone were extremely low (<0.098 μg/ml).It was significant that Pogostone was also active against some drug-resistant bacteria like MRSA.Furthermore,Pogostone showed antibacterial activity in vivo against Escherichia coli (E.coli) and MRSA via intraperitoneal injection.Ninety percent of the mice infected with E.coil could be protected at the concentrations of 50 and 100 mg/kg,and 60% of the mice at 25 mg/kg,while the rate of protection for the mice infected with MRSA was 60% and 50% at doses of 100 and 50 mg/kg,respectively.Conclusion Pogostone could be developed as a potential antibacterial agent for clinical therapy.

  10. Phenotype microarray profiling of the antibacterial activity of red cabbage

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    Hafidh RR

    2012-06-01

    Full Text Available Background: Functional food can be a potent source of wide array of biocomonents with antimicrobial activity. We investigated the antibacterial activity of red cabbage (RC extract on Gram negative and positive ATCC strains. Most intersting, we, for the first time, explored and analysed the complete phenotypic profile of RC-treated bacteria using Omnilog Phenotype Microarray. Results: This study revealed that the phenotype microarray (PM screen was a valuable tool in the search for compounds and their antibacterial mechanisms that can inhibit bacterial growth by affecting certain metabolic pathways. It was shown that RC exerted remarkable antibacterial effect on S. aureus and E. coli bacteria, and PM showed a wide range phenotypic profile of the exerted RC antibacterial activity. RC targeted the peptide, carbon, nutriontional assembly, and sulfur metbolic pathways altogether. The peptidoglycan synthesis pathway was inferred to be targeted by RC extract at a metabolic point different from other available cell wall-targeting drugs; these could be hot targets for the discovery of new therapy for many problematic microbes.Conclusions: Taken together, the phenotype microarray for functional food and medicinal plants can be a very useful tool for profiling their antimicrobial activity. Moreover, extracts of functional food can exert antibacterial activity by hitting a wide range of metabolic pathways, at the same time leading to very difficult condition for bacteria to rapidly develop resistance. Therefore, using functional foods or medicinal plants as such, or as extracts, can be superior on mono-targeting antibiotics if the optimal concentrations and conditions of these functional foods were sought.

  11. Antibacterial Activity of Ti₃C₂Tx MXene.

    Science.gov (United States)

    Rasool, Kashif; Helal, Mohamed; Ali, Adnan; Ren, Chang E; Gogotsi, Yury; Mahmoud, Khaled A

    2016-03-22

    MXenes are a family of atomically thin, two-dimensional (2D) transition metal carbides and carbonitrides with many attractive properties. Two-dimensional Ti3C2Tx (MXene) has been recently explored for applications in water desalination/purification membranes. A major success indicator for any water treatment membrane is the resistance to biofouling. To validate this and to understand better the health and environmental impacts of the new 2D carbides, we investigated the antibacterial properties of single- and few-layer Ti3C2Tx MXene flakes in colloidal solution. The antibacterial properties of Ti3C2Tx were tested against Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) by using bacterial growth curves based on optical densities (OD) and colonies growth on agar nutritive plates. Ti3C2Tx shows a higher antibacterial efficiency toward both Gram-negative E. coli and Gram-positive B. subtilis compared with graphene oxide (GO), which has been widely reported as an antibacterial agent. Concentration dependent antibacterial activity was observed and more than 98% bacterial cell viability loss was found at 200 μg/mL Ti3C2Tx for both bacterial cells within 4 h of exposure, as confirmed by colony forming unit (CFU) and regrowth curve. Antibacterial mechanism investigation by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) coupled with lactate dehydrogenase (LDH) release assay indicated the damage to the cell membrane, which resulted in release of cytoplasmic materials from the bacterial cells. Reactive oxygen species (ROS) dependent and independent stress induction by Ti3C2Tx was investigated in two separate abiotic assays. MXenes are expected to be resistant to biofouling and offer bactericidal properties.

  12. Design of New Antibacterial Enhancers Based on AcrB’s Structure and the Evaluation of Their Antibacterial Enhancement Activity

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    Yi Song

    2016-11-01

    Full Text Available Previously, artesunate (AS and dihydroartemisinine 7 (DHA7 were found to have antibacterial enhancement activity against Escherichia coli via inhibition of the efflux pump AcrB. However, they were only effective against E. coli standard strains. This study aimed to develop effective antibacterial enhancers based on the previous work. Our results demonstrate that 86 new antibacterial enhancers were designed via 3D-SAR and molecular docking. Among them, DHA27 had the best antibacterial enhancement activity. It could potentiate the antibacterial effects of ampicillin against not only E. coli standard strain but also clinical strains, and of β-lactam antibiotics, not non-β-lactamantibiotics. DHA27 could increase the accumulation of daunomycin and nile red within E. coli ATCC 35218, but did not increase the bacterial membrane permeability. DHA27 reduced acrB’s mRNA expression of E. coli ATCC 35218 in a dose-dependent manner, and its antibacterial enhancement activity is related to the degree of acrB mRNA expression in E. coli clinical strains. The polypeptides from AcrB were obtained via molecular docking assay; the pre-incubated polypeptides could inhibit the activity of DHA27. Importantly, DHA27 had no cytotoxicity on cell proliferation. In conclusion, among newly designed antibacterial enhancers, DHA27 had favorable physical and pharmacological properties with no significant cytotoxicity at effective concentrations, and might serve as a potential efflux pump inhibitor in the future.

  13. METAL OXIDE DOPED ANTIBACTERIAL POLYMERIC COATED TEXTILE MATERIALS AND ASSESSEMENT OF ANTIBACTERIAL ACTIVITY WITH ELECTRON SPIN RESONANCE

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    GEDIK Gorkem

    2017-05-01

    Full Text Available Antibacterial activity of a food conveyor belt is an essential property in some cases. However, every antibacterial chemical is not suitable to contact with food materials. Many metal oxides are suitable option for this purpose. The aim of this study was to investigate antibacterial properties of zinc oxide doped PVC polymer coated with electron spin resonance technique. Therefore, optimum zinc oxide containing PVC paste was prepared and applied to textile surface. Coating construction was designed as double layered, first layer did not contain antibacterial agent, thin second layer contained zinc oxide at 10-35% concentration. Oxygen radicals released from zinc oxide containing polymeric coated surface were spin trapped with DMPO (dimethylpyrroline-N-oxide spin trap and measured with Electron Spin Resonance (ESR. Besides conveyor belt samples, oxygen radical release from zinc oxide surface was measured with ESR under UV light and dark conditions. Oxygen radical release was determined even at dark conditions. Antibacterial properties were tested with ISO 22196 standard using Listeria innocua species. Measured antibacterial properties were related with ESR results. Higher concentration of zinc oxide resulted in higher antibacterial efficiency. DCFH-DA flourometric assay was carried out to determine oxidative stress insidebacteria. It is tought that, this technique will lead to decrease on the labour and time needed for conventional antibacterial tests.

  14. Antibacterial activities of medicinal plants used in Mexican traditional medicine.

    Science.gov (United States)

    Sharma, Ashutosh; Flores-Vallejo, Rosario Del Carmen; Cardoso-Taketa, Alexandre; Villarreal, María Luisa

    2017-08-17

    We provide an extensive summary of the in vitro antibacterial properties of medicinal plants popularly used in Mexico to treat infections, and we discuss the ethnomedical information that has been published for these species. We carried out a bibliographic investigation by analyzing local and international peer-reviewed papers selected by consulting internationally accepted scientific databases from 1995 to 2014. We provide specific information about the evaluated plant parts, the type of extracts, the tested bacterial strains, and the inhibitory concentrations for each one of the species. We recorded the ethnomedical information for the active species, as well as their popular names and local distribution. Information about the plant compounds that has been identified is included in the manuscript. This review also incorporates an extensive summary of the available toxicological reports on the recorded species, as well as the worldwide registries of plant patents used for treating bacterial infections. In addition, we provide a list with the top plant species with antibacterial activities in this review RESULTS: We documented the in vitro antibacterial activities of 343 plant species pertaining to 92 botanical families against 72 bacterial species, focusing particularly on Staphylococcus aureus, Mycobacterium tuberculosis, Escherichia coli and Pseudomonas aeruginosa. The plant families Asteraceae, Fabaceae, Lamiaceae and Euphorbiaceae included the largest number of active species. Information related to popular uses reveals that the majority of the plants, in addition to treating infections, are used to treat other conditions. The distribution of Mexican plants extended from those that were reported to grow in just one state to those that grow in all 32 Mexican states. From 75 plant species, 225 compounds were identified. Out of the total plant species, only 140 (40.57%) had at least one report about their toxic effects. From 1994 to July 2014 a total of 11

  15. Polybiguanide (PHMB) loaded in PLA scaffolds displaying high hydrophobic, biocompatibility and antibacterial properties

    Energy Technology Data Exchange (ETDEWEB)

    Llorens, Elena; Calderón, Silvia [Departament d' Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028 (Spain); Valle, Luis J. del, E-mail: luis.javier.del.valle@upc.edu [Departament d' Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028 (Spain); Puiggalí, Jordi [Departament d' Enginyeria Química, Universitat Politècnica de Catalunya, Av. Diagonal 647, Barcelona E-08028 (Spain); Center for Research in Nano-Engineering (CrNE), Universitat Politècnica de Catalunya, Edifici C, C/Pasqual i Vila s/n, Barcelona E-08028 (Spain)

    2015-05-01

    Polyhexamethylenebiguanide hydrochloride (PHMB), a low molecular weight polymer related to chlorohexidine (CHX), is a well-known antibacterial agent. In this study, polylactide (PLA) nanofibers loaded with PHMB were produced by electrospinning to obtain 3D biodegradable scaffolds with antibacterial properties. PLA fibers loaded with CHX were used as control. The electrospun fibers were studied and analyzed by SEM, FTIR, DSC and contact angle measurements. PHMB and CHX release from loaded scaffolds was evaluated, as well as their antibacterial activity and biocompatibility. The results showed that the nanofibers became smoother and their diameter smaller with increasing the amount of loaded PHMB. This feature led to an increase of both surface roughness and hydrophobicity of the scaffold. PHMB release was highly dependent on the hydrophilicity of the medium and differed from that determined for CHX. Lastly, PHMB-loaded PLA scaffolds showed antibacterial properties since they inhibited adhesion and bacterial growth, and exhibited biocompatible characteristics for the adhesion and proliferation of both fibroblast and epithelial cell lines. - Highlights: • Nanofibers of PLA-PHMB (antibacterial polymer) were prepared by electrospinning. • PHMB has hydrophilic character but the PLA-PHMB scaffolds were highly hydrophobic. • The high-hydrophobicity of the new scaffolds conditioned the release of PHMB. • The controlled release of PHMB inhibited the growth and bacterial adhesion. • PLA-PHMB scaffolds have biocompatibility with fibroblast and epithelial cells.

  16. SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF SCHIFF BASE DERIVATIVES OF 4-CHLORO-3-NITROBENZOIC ACID

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    Kumari Santosh

    2012-12-01

    Full Text Available 4-chloro-3-nitrobenzoic acid was selected as nucleus structure having good antibacterial property. It was thought worthwhile to synthesize Schiff base derivatives of 4-chloro-3-nitrobenzoic acid in search of better antibacterial agents. The compounds were synthesized by first reducing nitro group in presence of Sn/HCl to 3-amino-4-chlorobenzoic acid, which on treatment with substituted benzaldehyde afforded the synthesis of the envisaged compounds. The synthesized compounds were purified and chemically characterized. They were screened for their antibacterial activity and result suggested that SKY-1, SKY-5 and SKY-8 were highly active against both Gram (+ and Gram(- bacteria like B.subtilis, S.aureus and E.coli whereas all are were found moderately to inactive against P.aeruginosa.

  17. Antibacterial activity of plant extracts from Brazil against fish pathogenic bacteria

    Science.gov (United States)

    Castro, S.B.R.; Leal, C.A.G.; Freire, F.R.; Carvalho, D.A.; Oliveira, D.F.; Figueiredo, H.C.P.

    2008-01-01

    The aim of this work was to evaluate the antibacterial activity of Brazilian plants extracts against fish pathogenic bacteria. Forty six methanolic extracts were screened to identify their antibacterial properties against Streptococcus agalactiae, Flavobacterium columnare and Aeromonas hydrophila. Thirty one extracts showed antibacterial activity. PMID:24031303

  18. Synthesis and Antibacterial Activity of Novel 2-Oxo-pyrrolidinyl Oxazolidinones

    Energy Technology Data Exchange (ETDEWEB)

    Bhattarai, Deepak; Lee, Sun Hee; Kim, Hyeong Kyu; Kang, Soon Bang; Pae, Ae Nim; Kim, Eunice Eunkyeong; Keum, Gyo Chang [Korea Institute of Science and Technology, Seoul (Korea, Republic of); Oh, Tae Gwon; Cho, Sang Nae [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2012-04-15

    Novel antibacterial oxazolidinones bearing pyrrolidinone ring system at the C-5 side chain were synthesized and their in vitro antibacterial activities were evaluated. Most of the synthesized oxazolidinones showed good antibacterial activity against the Gram-positive and Gram-negative bacteria tested

  19. Soya bean tempe extracts show antibacterial activity against Bacillus cereus cells and spores

    NARCIS (Netherlands)

    Roubos-van den Hil, P.J.; Dalmas, E.; Nout, M.J.R.; Abee, T.

    2010-01-01

    Aims: Tempe, a Rhizopus ssp.-fermented soya bean food product, was investigated for bacteriostatic and/or bactericidal effects against cells and spores of the food-borne pathogen Bacillus cereus. Methods and results: Tempe extract showed a high antibacterial activity against B. cereus ATCC 14579 bas

  20. Antibacterial activity and characteristics of modified ferrite powder coated with a gemini pyridinium salt molecule.

    Science.gov (United States)

    Shirai, Akihiro; Maeda, Takuya; Ohkita, Motoaki; Nagamune, Hideaki; Kourai, Hiroki

    2007-09-01

    This report describes the synthesis of an antibacterial material consisting of a gemini quaternary ammonium salt (gemini-QUAT) immobilized on ferrite powder, and its antibacterial activity. A gemini-QUAT containing two pyridinium residues per molecule, 4,4'-[1,3-(2,2-dihydroxylmethyl-1,3-dithiapropane)]bis (1-octylpyridinium bromide), was immobilized on ferrite powder by a reaction between the hydroxyl group of the QUAT and trimethoxysilane. Immobilization of the gemini-QUAT on ferrite (F-gemini-QUAT) was confirmed when the dye, bromophenol blue, was released from F-gemini-QUAT-dye after contact between ferrite and the dye. Elemental analysis of the QUAT-ferrite determined the molar amount of QUAT on the ferrite. The antibacterial effect of the ferrite was investigated using a batch treatment system, and this effect was compared with that of another QUAT-ferrite (F-mono-QUAT) binding a mono-QUAT, which possesses one pyridinium residue, prepared by the same immobilization method as F-gemini-QUAT. Results indicated the F-gemini QUAT possessed a higher bactericidal potency and broader antibacterial spectrum compared to F-mono-QUAT. In addition, this study suggested that gemini-QUATs possessed high bactericidal potency without being influenced by immobilization to materials, and the antibacterial activity and characteristics of F-gemini-QUAT could be attributed to the unique structure of the immobilized gemini-QUAT.

  1. Potential antibacterial activity of some Saudi Arabia honey

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    Ahmed G. Hegazi

    2017-02-01

    Full Text Available Aim: The aim of this study was to investigate the potential antibacterial activity of some Saudi Arabia honey against selected bacterial strains of medical importance. Materials and Methods: A total of 10 Saudi Arabia honey used to evaluate their antimicrobial activity against some antibiotic-resistant pathogenic bacterial strains. The bacterial strains were Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa. Results: The antibacterial activity of Saudi honey against five bacterial strains showed different levels of inhibition according to the type of honey. The overall results showed that the potential activity was differing according to the pathogen and honey type. Conclusion: It could be concluded that the Saudi honey inhibit the growth of bacterial strains and that honey can be used as complementary antimicrobial agent against selected pathogenic bacteria.

  2. Anti-bacterial activity of some Brazilian medicinal plants.

    Science.gov (United States)

    de Lima, Maria Raquel Ferreira; de Souza Luna, Josiane; dos Santos, Aldenir Feitosa; de Andrade, Maria Cristina Caño; Sant'Ana, Antônio Euzébio Goulart; Genet, Jean-Pierre; Marquez, Béatrice; Neuville, Luc; Moreau, Nicole

    2006-04-21

    Extracts from various organs of 25 plants of Brazilian traditional medicine were assayed with respect to their anti-bacterial activities against Escherichia coli, a susceptible strain of Staphylococcus aureus and two resistant strains of Staphylococcus aureus harbouring the efflux pumps NorA and MsrA. Amongst the 49 extracts studied, 14 presented anti-bacterial activity against Staphylococcus aureus, including the ethanolic extracts from the rhizome of Jatropha elliptica, from the stem barks of Schinus terebinthifolius and Erythrina mulungu, from the stems and leaves of Caesalpinia pyramidalis and Serjania lethalis, and from the stem bark and leaves of Lafoensia pacari. The classes of compounds present in the active extracts were determined as a preliminary step towards their bioactivity-guided separation. No extracts were active against Escherichia coli.

  3. Antibacterial Potential and Antioxidant Activity of Polyphenols of Sesbania grandiflora

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    M.B. Ouattara

    2011-07-01

    Full Text Available The antibacterial and antioxidant activity of Sesbanial grandiflora used in traditional pharmacopeia in Burkina Faso and elsewhere was evaluated. Aqueous, methanolic and hydro-acetone extractions were carried out on the leaves, stems, and granules, pods of fruit and roots of the plant. The phytochimic groups were identified by the tests of characterization, then quantified by the tests of proportioning of total phenolics, flavonoides and tanins. Specific compounds to these phytochimic groups were also identified by the analysis in Thin layer chromatography among which the gallic acid, the caffeic acid, Kaempferol, Quercetin, Rutin. An important antioxidant activity of the same extracts was evaluated by the test of reduction of the stable radical, the 2,2-diphényl-1-picrylhydrazyl (DPPH* and the test of reduction of iron (FRAP. This activity is related to phenolic compounds contained in the extracts. Extracts also expressed a good antibacterial activity.

  4. Antimycobacterial and Antibacterial Activity of Allium sativum Bulbs.

    Science.gov (United States)

    Viswanathan, V; Phadatare, A G; Mukne, Alka

    2014-05-01

    Tuberculosis is one of the major public health problems faced globally. Resistance of Mycobacterium tuberculosis to antitubercular agents has called for an urgent need to investigate newer drugs to combat tuberculosis. Garlic (Allium sativum) is an edible plant which has generated a lot of curiosity throughout human history as a medicinal plant. Garlic contains sulfur compounds like allicin, ajoene, allylmethyltrisulfide, diallyltrisulfide, diallyldisulphide and others which exhibit various biological properties like antimicrobial, anticancer, antioxidant, immunomodulatory, antiinflammatory, hypoglycemic, and cardiovascular effects. According to various traditional systems of medicine, garlic is one of the established remedies for tuberculosis. The objective of the current study was to investigate in vitro antimycobacterial activity as well as anti-bacterial activity of various extracts rich in specific phytoconstituents from garlic. Preparation of garlic extracts was done based on the chemistry of the constituents and their stability. The estimation of in vitro antimycobacterial activity of different garlic extracts was done using Resazurin microtire plate assay technique whereas activity of garlic oil was evaluated by colony count method. The antibacterial activity of extracts and oil was estimated by zone of inhibition method. Extracts of garlic rich in allicin and ajoene showed appreciable antimycobacterial activity as compared to standard drugs. Garlic oil demonstrated significant antibacterial activity, particularly against methicillin-resistant Staphylococcus aureus.

  5. Antimycobacterial and antibacterial activity of Allium sativum bulbs

    Directory of Open Access Journals (Sweden)

    V. Viswanathan

    2014-01-01

    Full Text Available Tuberculosis is one of the major public health problems faced globally. Resistance of Mycobacterium tuberculosis to antitubercular agents has called for an urgent need to investigate newer drugs to combat tuberculosis. Garlic (Allium sativum is an edible plant which has generated a lot of curiosity throughout human history as a medicinal plant. Garlic contains sulfur compounds like allicin, ajoene, allylmethyltrisulfide, diallyltrisulfide, diallyldisulphide and others which exhibit various biological properties like antimicrobial, anticancer, antioxidant, immunomodulatory, antiinflammatory, hypoglycemic, and cardiovascular effects. According to various traditional systems of medicine, garlic is one of the established remedies for tuberculosis. The objective of the current study was to investigate in vitro antimycobacterial activity as well as anti-bacterial activity of various extracts rich in specific phytoconstituents from garlic. Preparation of garlic extracts was done based on the chemistry of the constituents and their stability. The estimation of in vitro antimycobacterial activity of different garlic extracts was done using Resazurin microtire plate assay technique whereas activity of garlic oil was evaluated by colony count method. The antibacterial activity of extracts and oil was estimated by zone of inhibition method. Extracts of garlic rich in allicin and ajoene showed appreciable antimycobacterial activity as compared to standard drugs. Garlic oil demonstrated significant antibacterial activity, particularly against methicillin-resistant Staphylococcus aureus.

  6. The effect of lipophilicity on the antibacterial activity of some 1-benzylbenzimidazole derivatives

    Directory of Open Access Journals (Sweden)

    D. J. BARNA

    2008-10-01

    Full Text Available In the present paper, the antibacterial activity of some 1-benzylbenzimidazole derivatives were evaluated against the Gram-negative bacteria Escherichia coli. The minimum inhibitory concentration was determined for all the compounds. Quantitative structure–activity relationship (QSAR was employed to study the effect of the lipophilicity parameters (log P on the inhibitory activity. Log P values for the target compounds were experimentally determined by the “shake-flask” method and calculated by using eight different software products. Multiple linear regression was used to correlate the log P values and antibacterial activity of the studied benzimidazole derivatives. The results are discussed based on statistical data. The most acceptable QSAR models for the prediction of the antibacterial activity of the investigated series of benzimidazoles were developed. High agreement between the experimental and predicted inhibitory values was obtained. The results of this study indicate that the lipophilicity parameter has a significant effect on the antibacterial activity of this class of compounds, which simplifies the design of new biologically active molecules.

  7. Albumin reduces the antibacterial activity of polyhexanide-biguanide-based antiseptics against Staphylococcus aureus and MRSA.

    Science.gov (United States)

    Kapalschinski, N; Seipp, H M; Onderdonk, A B; Goertz, O; Daigeler, A; Lahmer, A; Lehnhardt, M; Hirsch, T

    2013-09-01

    Wound infection is one of the major complications in acute and chronic wound healing. Antiseptic solutions and wound irrigating agents are routinely used for therapy and prevention in healthcare today. Even if wound exudate contains total protein concentrations up to 9.3% and albumin concentrations up to 2.7% its influence to the antibacterial efficacy of these agents is barely investigated. This study analyzed the antibacterial effect of polyhexanide biguanide (PHMB) agents (PHMB-concentration 0.005-0.1%) against Staphylococcus aureus and methicillin-resistant-S. aureus (MRSA) after 2min incubation in presents of albumin in different concentrations (0-3%) in a standardized quantitative suspension assay. A significant decrease of the antibacterial activity against S. aureus was shown for a PHMB-concentration of 0.005% from 0.3% albumin (p<0.05), respectively highly significant from 0.75% (p<0.01) on. Thereby the loss of antimicrobial effect was presented as a linear correlation to the rising concentration of albumin. Furthermore a reduction of the antibacterial activity against MRSA in comparison to S. aureus was presented, for albumin concentrations from 3% on highly significant (p<0.01). The study showed that albumin causes a significant decrease of the antibacterial potency of PHMB-based antiseptics. Furthermore a diminished potency of the investigated substances for MRSA-contaminated wounds must be taken in consideration. If in vitro experiments show a significant decrease of antibacterial efficacy in the presence of albumin a sufficient activity of PHMB-based agents in clinical practice, especially in cases of exuding wounds or dried-up exudates, cannot be expected. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  8. Antibacterial and allelopathic activity of extract from Castanea sativa leaves.

    Science.gov (United States)

    Basile, A; Sorbo, S; Giordano, S; Ricciardi, L; Ferrara, S; Montesano, D; Castaldo Cobianchi, R; Vuotto, M L; Ferrara, L

    2000-08-01

    Following the extraction of Castanea sativa with an aqueous solution of sulfuric acid (pH 3.0), the ethyl acetate soluble fraction was tested for its antibacterial and allelopathic activity. The extract was shown to have pronounced antibacterial effects against seven of the eight strains of Gram-positive and Gram-negative bacteria used (MIC in the range of 64-256 microg/ml and MBC in the range of 256-512 microg/ml). The active fraction was analyzed by TLC and HPLC showing the presence of rutin, hesperidin, quercetin, apigenin, morin, naringin, galangin and kaempferol. Standards of the identified flavonoids were tested against the same bacterial strains. The highest activity was shown by quercetin, rutin and apigenin. The allelopathic effect was tested against Raphanus sativus seed germination. The extract, quercetin, rutin and apigenin caused a decrease in the percentage of seed germination and root and epicotyl growth.

  9. [Antioxidant and antibacterial activities of dimeric phenol compounds].

    Science.gov (United States)

    Ogata, Masahiro

    2008-08-01

    We studied the antioxidant and antibacterial activities of monomeric and dimeric phenol compounds. Dimeric compounds had higher antioxidant activities than monomeric compounds. Electron spin resonance spin-trapping experiments showed that phenol compounds with an allyl substituent on their aromatic rings directly scavenged superoxide, and that only eugenol trapped hydroxyl radicals. We developed a generation system of the hydroxyl radical without using any metals by adding L-DOPA and DMPO to PBS or MiliQ water in vitro. We found that eugenol trapped hydroxyl radicals directly and is metabolized to a dimer. On the other hand, dipropofol, a dimer of propofol, has strong antibacterial activity against Gram-positive bacteria. However, it lacks solubility in water and this property is assumed to limit its efficacy. We tried to improve the solubility and found a new solubilization method of dipropofol in water with the addition of a monosaccharide or ascorbic acid.

  10. Cytotoxic and Antibacterial Activities of Constituents from Calophyllum ferrugineum Ridley

    Directory of Open Access Journals (Sweden)

    Nurul Iman Aminudin

    2016-03-01

    Full Text Available This study evaluated the chemical composition of Calophyllum ferrugineum, cytotoxicity against human breast cancer (MCF-7 and human lung carcinoma (A-549 cell lines as well as antibacterial activities against two Gram-positive bacteria, S. aureus and B. subtilis and two Gram-negative bacteria, P. aeruginosa and E. coli. Phytochemical investigations of the bark extract yielded isoapetalic acid (1, apetalic acid (2, 6-hydroxy-2-methoxyxanthone (3 and ent-epicatechin (4. Meanwhile, betulinic acid (5, protocatechuic acid (6 and amentoflavone (7 were isolated from the leave extract. Isoapetalic acid (1 and apetalic acid (2 exhibited cytotoxic activities towards both cancer cell lines and both Gram-positive bacteria. Compounds (3-7 were inactive or showed moderate activities towards cytotoxic and antibacterial tests. This study presents the first report on the phytochemicals investigation from C. ferrugineum and all compounds are reported for the first time from this source.

  11. Antibacterial activities of some Indian traditional plant extracts

    Directory of Open Access Journals (Sweden)

    N Prasannabalaji

    2012-05-01

    Full Text Available Objective: To evaluate the in vitro antibacterial activity of various solvent extracts of South Indian traditional medicinal plants Ocimum sanctum, Ocimum gratissimum, Aegle marmelos, and Adhatoda vasica leaves against clinical pathogens of human origin. Methods: The antimicrobial activity of different solvents crude extract of four medicinal plants used in traditional Indian medicine was tested by disc diffusion method against five bacterial pathogens: Escherichia coli, Staphylococcus aureus, Salmonella typhi, Salmonella paratyphi and klebsiella pneumoniae.. The minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC was determined for evaluating the potential plant extract. Results: The antibacterial results showed methanol extracts (0.4 g/ml of Ocimum gratissimum and Ocimum sanctum showed maximum zone of inhibition (30 mm and 25.5 mm, respectively against Salmonella typhi. MIC was tested at various concentrations from 0.625 mg/ml to 0.039 mg/ml for all the plant extracts. At the lowest concentration (0.039mg/ml tested, methanol extracts of Ocimum gratissimum showed higher MIC against Salmonella typhi and Salmonella paratyphi where as the methanolic extracts of Ocimum gratissimum showed potent activity against Staphylococcus aureus at 0.078 mg/ml. Methanol extract (0.4 g/ml of Aegle marmelos showed significant inhibitory activity of 22.5mm and MIC value of 0.156.mg/ml against E. coli strain. The Klebsiella spp was the most resistant strain of all and various concentrations Adhatoda vasica extract showed less activity against the tested pathogens. Conclusions: The present screening result demonstrated that the Indian traditional medicinal plants Ocimum sanctum, Ocimum gratissimum, Aegle marmelos methanol leaf extract has potent antibacterial activity and the studied plants may be new source for novel antibacterial compound discovery for treating drugs resistant human pathogens.

  12. Radical scavenging and antibacterial activity of Arnebia benthamii methanol extract

    Institute of Scientific and Technical Information of China (English)

    Showkat A Ganie; Asima Jan; Sabeera Muzaffar; Bilal A Zargar; Rabia Hamid; M Afzal Zargar

    2012-01-01

    Objective:To evaluate in vitro antioxidant and antibacterial activity of methanolic extract of Arnebia benthamii (A. benthamii) whole plant. Methods: Plasmid damage was analyzed by agarose gell electrophoresis. Calf thymus DNA was monitored by TBARS formation. DPPH, reducing power and lipid peroxidation was evaluated by using standard procedures. Antibacterial assay was monitored by disc diffusion method. Results: DPPH radical scavenging and hydroxyl radical scavenging potential of the plant revealed that the extract to be active radical scavenger. Reducing (Fe3+-Fe2+) power and lipid peroxidation inhibition efficiency (TBARS assay) of the extract was also evaluated and the extract showed promising activity in preventing lipid peroxidation and might prevent oxidative damages to biomolecules. The extract offered a significant protection against plasmid and calf thymus DNA damage induced by hydroxyl radicals. The extract was also evaluated on different bacterial strains and the maximum antibacterial activity was exhibited against Escherichia coli (E. coli) when compared with standard drug. Conclusions:These findings demonstrate that the methanol extract of A. benthamii has excellent anti-oxidant activities and could be considered as a potential source of lead molecules for pharmaceutical industries.

  13. ANTIBACTERIAL ACTIVITY, PHYTOCHEMICAL SCREENING AND ANTIOXIDANT ACTIVITY OF STEM OF NICOTIANA TABACUM

    National Research Council Canada - National Science Library

    Y Sharma; D Dua; A Nagar; N S Srivastava

    2016-01-01

    .... The purpose of this present study is to investigate the antibacterial activity, phytochemical screening and the antioxidant activity of aqueous and alcoholic extracts of the stem of Nicotiana tabacum...

  14. Mesoporous TiO2 implants for loading high dosage of antibacterial agent

    Science.gov (United States)

    Park, Se Woong; Lee, Donghyun; Choi, Yong Suk; Jeon, Hoon Bong; Lee, Chang-Hoon; Moon, Ji-Hoi; Kwon, Il Keun

    2014-06-01

    We have fabricated mesoporous thin films composed of TiO2 nanoparticles on anodized titanium implant surfaces for loading drugs at high doses. Surface anodization followed by treatment with TiO2 paste leads to the formation of mechanically stable mesoporous thin films with controllable thickness. A series of antibacterial agents (silver nanoparticles, cephalothin, minocycline, and amoxicillin) were loaded into the mesoporous thin films and their antibacterial activities were evaluated against five bacterial species including three oral pathogens. Additionally, two agents (silver nanoparticles and minocycline) were loaded together on the thin film and tested for antibacterial effectiveness. The combination of silver nanoparticles and minocycline was found to display a wide range of effectiveness against all tested bacteria.

  15. Enhanced transparency, mechanical durability, and antibacterial activity of zinc nanoparticles on glass substrate

    Science.gov (United States)

    Choi, Hyung-Jin; Choi, Jin-Seok; Park, Byeong-Ju; Eom, Ji-Ho; Heo, So-Young; Jung, Min-Wook; An, Ki-Seok; Yoon, Soon-Gil

    2014-01-01

    Homogeneously distributed zinc nanoparticles (NPs) on the glass substrate were investigated for the transmittance, mechanical durability, and antibacterial effect. The buffered Ti NPs between Zn NPs and glass substrate were studied for an enhancement of the transmittance and mechanical endurance. The Ti NPs buffered Zn NPs showed a high transmittance of approximately 91.5% (at a wavelength of 550 nm) and a strong antibacterial activity for Staphylococcus aureus and Escherichia coli bacteria. The buffered Ti NPs are attractive for an excellent mechanical endurance of the Zn NPs. The Zn NPs did not require the protection layer to prevent the degradation of the performance for both the antibacterial effect and the transmittance. PMID:25183360

  16. Antibacterial activity and cytotoxicity of multi-walled carbon nanotubes decorated with silver nanoparticles.

    Science.gov (United States)

    Seo, Youngmin; Hwang, Jangsun; Kim, Jieun; Jeong, Yoon; Hwang, Mintai P; Choi, Jonghoon

    2014-01-01

    Recently, various nanoscale materials, including silver (Ag) nanoparticles, have been actively studied for their capacity to effectively prevent bacterial growth. A critical challenge is to enhance the antibacterial properties of nanomaterials while maintaining their biocompatibility. The conjugation of multiple nanomaterials with different dimensions, such as spherical nanoparticles and high-aspect-ratio nanotubes, may increase the target-specific antibacterial capacity of the consequent nanostructure while retaining an optimal biocompatibility. In this study, multi-walled carbon nanotubes (MWCNTs) were treated with a mixture of acids and decorated with Ag nanoparticles via a chemical reduction of Ag cations by ethanol solution. The synthesized Ag-MWCNT complexes were characterized by transmission electron microscopy, X-ray diffractometry, and energy-dispersive X-ray spectroscopy. The antibacterial function of Ag-MWCNTs was evaluated against Methylobacterium spp. and Sphingomonas spp. In addition, the biocompatibility of Ag-MWCNTs was evaluated using both mouse liver hepatocytes (AML 12) and human peripheral blood mononuclear cells. Finally, we determined the minimum amount of Ag-MWCNTs required for a biocompatible yet effective antibacterial treatment modality. We report that 30 μg/mL of Ag-MWCNTs confers antibacterial functionality while maintaining minimal cytotoxicity toward both human and animal cells. The results reported herein would be beneficial for researchers interested in the efficient preparation of hybrid nanostructures and in determining the minimum amount of Ag-MWCNTs necessary to effectively hinder the growth of bacteria.

  17. Highly antibacterial UHMWPE surfaces by implantation of titanium ions

    Energy Technology Data Exchange (ETDEWEB)

    Delle Side, D., E-mail: domenico.delleside@le.infn.it [LEAS, Dipartimento di Matematica e Fisica “Ennio de Giorgi”, Università del Salento, Lecce (Italy); Istituto Nazionale di Fisica Nucleare – Sezione di Lecce, Lecce (Italy); Nassisi, V.; Giuffreda, E.; Velardi, L. [LEAS, Dipartimento di Matematica e Fisica “Ennio de Giorgi”, Università del Salento, Lecce (Italy); Istituto Nazionale di Fisica Nucleare – Sezione di Lecce, Lecce (Italy); Alifano, P.; Talà, A.; Tredici, S.M. [Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Università del Salento, Lecce (Italy)

    2014-07-15

    The spreading of pathogens represents a serious threat for human beings. Consequently, efficient antimicrobial surfaces are needed in order to reduce risks of contracting severe diseases. In this work we present the first evidences of a new technique to obtain a highly antibacterial Ultra High Molecular Weight Polyethylene (UHMWPE) based on a non-stoichiometric titanium oxide coating, visible-light responsive, obtained through ion implantation.

  18. Antibacterial Activity of a Cardanol from Thai Apis mellifera Propolis

    Science.gov (United States)

    Boonsai, Pattaraporn; Phuwapraisirisan, Preecha; Chanchao, Chanpen

    2014-01-01

    Background: Propolis is a sticky, dark brown resinous residue made by bees that is derived from plant resins. It is used to construct and repair the nest, and in addition possesses several diverse bioactivities. Here, propolis from Apis mellifera from Nan province, Thailand, was tested for antibacterial activity against Gram+ve (Staphylococcus aureus and Paenibacillus larvae) and Gram-ve (Escherichia coli) bacteria. Materials and methods: The three bacterial isolates were confirmed for species designation by Gram staining and analysis of the partial sequence of 16S rDNA. Propolis was sequentially extracted by methanol, dichloromethane and hexane. The antibacterial activity was determined by agar well diffusion and microbroth dilution assays using streptomycin as a positive control. The most active crude extract was further purified by quick column and adsorption chromatography. The apparent purity of each bioactive fraction was tested by thin layer chromatography. The chemical structure of the isolated bioactive compound was analyzed by nuclear magnetic resonance (NMR). Results: Crude methanol extract of propolis showed the best antibacterial activity with a minimum inhibition concentration (MIC) value of 5 mg/mL for S. aureus and E. coli and 6.25 mg/mL for P. larvae. After quick column chromatography, only three active fractions were inhibitory to the growth of S. aureus and E. coli with MIC values of 6.25 and 31.3 µg/mL, respectively. Further adsorption chromatography yielded one pure bioactive fraction (A1A) with an IC50 value of 0.175 µg/mL for E. coli and 0.683 µg/mL for P. larvae, and was determined to be cardanol by NMR analysis. Scanning and transmission electron microscopy analysis revealed unusual shaped (especially in dividing cells), damaged and dead cells in cardanol-treated E. coli. Conclusion: Thai propolis contains a promising antibacterial agent. PMID:24578609

  19. Diversity and Antibacterial Activities of Fungi Derived from the Gorgonian Echinogorgia rebekka from the South China Sea

    Directory of Open Access Journals (Sweden)

    Chang-Yun Wang

    2011-08-01

    Full Text Available The diversity of symbiotic fungi associated with the gorgonian coral Echinogorgia rebekka from the Weizhou coral reef in the South China Sea was investigated. Combined with morphologic traits, ITS-rDNA sequences revealed 18 fungal strains from this gorgonian. All of the 18 fungi belonged to the phylum Ascomycota and were distributed among seven genera in five orders: Eurotiales (Aspergillus and Penicillium, Pleosporales (Alternaria, Capnodiales (Cladosporium, Trichosphaeriales (Nigrospora and Hypocreales (Hypocrea and Nectria. Antibacterial activities of these fungal strains were investigated with five pathogenic bacteria. All of the 18 fungal strains displayed different levels of antibacterial activities, most of which exhibited moderate to high antibacterial activities to the Gram-positive pathogens Staphylococcus aureus and Micrococcus tetragenus, and showed relatively low bioactivities to other three pathogenic bacteria. Several fungal strains in the genera Penicillium and Cladosporium with strong antibacterial activities provide potential for further research on isolation of bioactive secondary metabolites.

  20. A Study of the Antibacterial Activity of Polyhexamethylene Bigaunide on Cotton Substrate

    NARCIS (Netherlands)

    Amrit, Usha; Hendrix, R.; Dutschk, Victoria; Warmoeskerken, Marinus; Mijovic, Budimir; Ujevic, Darko; Petrak, Slavenka; Marija Grancaric, Ana; Ira Glogar, Martinia; Salopek Cubric, Ivana

    2012-01-01

    Interest in antibacterial textiles has been increasing recently. Different kinds of antibacterial textiles with different effectivity are being sold in the market. The influence of time on the antibacterial activity of such textiles is not known generally. The goal of this research was to study the

  1. A Study of the Antibacterial Activity of Polyhexamethylene Bigaunide on Cotton Substrate

    NARCIS (Netherlands)

    Amrit, U.R.; Hendrix, R.; Dutschk, V.; Warmoeskerken, M.M.C.G.; Mijovic, Budimir; Ujevic, Darko; Petrak, Slavenka; Grancaric, Marija Ana; Glogar, Ira Martinia; Salopek Cubric, Ivana

    2012-01-01

    Interest in antibacterial textiles has been increasing recently. Different kinds of antibacterial textiles with different effectivity are being sold in the market. The influence of time on the antibacterial activity of such textiles is not known generally. The goal of this research was to study the

  2. Evaluation of cytotoxicity, immune compatibility and antibacterial activity of biogenic silver nanoparticles.

    Science.gov (United States)

    Składanowski, M; Golinska, P; Rudnicka, K; Dahm, H; Rai, M

    2016-12-01

    The study was focused on assessment of antibacterial activity, cytotoxicity and immune compatibility of biogenic silver nanoparticles (AgNPs) synthesized from Streptomyces sp. NH28 strain. Nanoparticles were biosynthesized and characterized by UV-Vis spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, nanoparticle tracking analysis system and zeta potential. Antibacterial activity was tested against Gram-positive and Gram-negative bacteria; minimal inhibitory concentration was recorded. Cytotoxicity was estimated using L929 mouse fibroblasts via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. Biocompatibility of AgNPs was performed using THP1-XBlue™ cells. Biogenic AgNPs presented high antibacterial activity against all tested bacteria. Minimum inhibitory concentration of AgNPs against bacterial cells was found to be in range of 1.25-10 μg/mL. Silver nanoparticles did not show any harmful interaction to mouse fibroblast cell line, and no activation of nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) cells was observed at concentration below 10 µg/mL. The half-maximal inhibitory concentration (IC50) value was established at 64.5 μg/mL. Biological synthesis of silver can be used as an effective system for formation of metal nanoparticles. Biosynthesized AgNPs can be used as an antibacterial agent, which can be safe for eukaryotic cells.

  3. Preservation of viability and antibacterial activity of Lactobacillus spp. in calcium alginate beads.

    Science.gov (United States)

    Brachkova, Mariya I; Duarte, Maria A; Pinto, João F

    2010-12-23

    The objective of the study was to produce calcium alginate beads able to deliver Lactobacillus spp. (Lactobacillus plantarum, Lactobacillus rhamnosus GG, Lactobacillus bulgaricus and Lactobacillus lactis) with preserved viability and antibacterial activity. Four types of beads, containing entrapped (E), surface and entrapped (ES), surface (S) and concentrated surface and entrapped lactobacilli (C(ES)) were prepared and physically characterized. The antibacterial activity of lactobacilli cultures before and after immobilization, freeze-drying and throughout storage was studied in relationship to the viable number of lactobacilli. Multi-resistant clinical isolates (methicillin-resistant Staphylococcus aureus, vancomycine-resistant Enterococcus faecalis, VIM-2-metalo-β-lactamase producing Pseudomonas aeruginosa and CTX-M-15-β-lactamase producing strains: Escherichia coli and Klebsiella pneumoniae) were used as indicator strains. Alginate beads in which lactobacilli proliferated to the beads surface (ES and C(ES)) differed significantly from the other types of beads in their physicochemical properties, showing smoother surface morphology, more spherical shape, bigger weight, lower calcium content, density and crushing force. Lactobacilli cultures, at high cell concentrations (10(8)cfu/ml) were active against both Gram-positive and negative multi-resistant bacteria. Beads containing both entrapped and surface lactobacilli (ES) resulted in viability and antibacterial activity most similar to non-processed lactobacilli cultures. The viability and antibacterial activity of the immobilized lactobacilli remained stable after 6 months storage.

  4. Synthesis and antibacterial activity of silver nanoparticles with different sizes

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Castanon, G. A., E-mail: mtzcastanon@fciencias.uaslp.m [UASLP, Maestria en Ciencias Odontologicas, Facultad de Estomatologia (Mexico); Nino-Martinez, N. [UASLP, Instituto de Metalurgia (Mexico); Martinez-Gutierrez, F., E-mail: fidel@uaslp.m [UASLP, Facultad de Ciencias Quimicas (Mexico); Martinez-Mendoza, J. R.; Ruiz, Facundo [UASLP, Facultad de Ciencias (Mexico)

    2008-12-15

    Silver nanoparticles with different sizes (7, 29, and 89 nm mean values) were synthesized using gallic acid in an aqueous chemical reduction method. The nanoparticles were characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), and ultraviolet-visible (UV-Vis) absorption spectroscopy; the antibacterial activity was assessed using the standard microdilution method, determining the minimum inhibitory concentration (MIC) according to the National Committee for Clinical Laboratory Standards. From the microscopies studies (TEM) we observed that silver nanoparticles have spherical (7 and 29 nm) and pseudospherical shape (89 nm) with a narrow size distribution. The sizes of the silver nanoparticles were controlled by varying some experimental conditions. It was found that the antibacterial activity of the nanoparticles varies when their size diminishes.

  5. ANTIBACTERIAL ACTIVITY OF GERMACRONE SESQUITERPENE FROM CURCUMA XANTHORRHIZA RHIZOMES

    Directory of Open Access Journals (Sweden)

    Hartiwi Diastuti

    2016-09-01

    Full Text Available The aim of this research was to isolate and indentify the terpenoid compound from Curcuma xanthorrhiza rhizomes and its antibacterial activity. Isolation was carried out by using vacuum liquid chromatography and centrifugal chromatography. The structure was determined by NMR spectroscopy (1H-NMR, 13C-NMR 1D and 2D, then compare with data from literatures. Antibacterial test was carried out by using microdillution methods and evaluated against eight bacteria. They are Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Enterobacter aerogenes, Pseudomonas aeruginosa, Salmonella typhi, Shigella dysentriae and Vibrio cholerae. The result showed that the isolate was a white crystal which was indetified as germacron-type sesquiterpene. Germacron have highest activity againts P. aeruginosa, MIC 15.6 µg/mL and MBC 31.2 µg/mL.

  6. Synthesis and Antibacterial Activity of Antibiotic-Functionalized Graphite Nanofibers

    Directory of Open Access Journals (Sweden)

    Madeline Rotella

    2015-01-01

    Full Text Available Surface functionalization of nanomaterials is an area of current investigation that supports the development of new biomaterials for applications in biology and medicine. Herein we describe the synthesis, characterization, and antibacterial properties of the first examples of antibiotic-labeled graphitic carbon nanofibers (GCNFs covalently functionalized with aminoglycoside and quinolone antibiotics. Ruthenium tetroxide oxidation of herringbone GCNFs gave higher amounts of surface carboxyl groups than previous methods. These carboxyl groups served as sites of attachment for antibiotics by acyl substitution. Bioassay of these novel, functionalized GCNFs using serial dilution and optical density methods demonstrated that antibiotic-labeled GCNFs possess significant antibacterial activity against Pseudomonas aeruginosa. The activity we observe for aminoglycoside-functionalized GCNFs suggests a membranolytic mechanism of action.

  7. Activity of endodontic antibacterial agents against selected anaerobic bacteria

    Directory of Open Access Journals (Sweden)

    Ferreira Cláudio Maniglia

    2002-01-01

    Full Text Available The antimicrobial activity of substances used as antibacterial agents (solutions of 10% calcium hydroxide, camphorated paramonochlorophenol - PMCC, 2% chlorhexidine digluconate and 10% castor oil plant detergent on anaerobic bacteria (Fusobacterium nucleatum ATCC 25586, Prevotella nigrescens ATCC 33563, Clostridium perfringens ATCC 13124 and Bacteroides fragilis ATCC 25285, using a broth dilution technique, was evaluated in vitro. For determination of minimum inhibitory and minimum bactericide concentrations (MIC and MBC, two culture broths, Reinforced Clostridial Medium (RCM and supplemented Brucella, standardized inoculum and serially diluted solutions were used. All antibacterial agents presented antimicrobial activity that varied for different bacteria. There were no differences in the performance of the two broths. Chlorhexidine digluconate was the most effective, with the lowest MICs, followed by castor oil detergent, PMCC and calcium hydroxide. C. perfringens and B. fragilis were the most resistant bacteria to all agents.

  8. Phenolic content, antioxidant and antibacterial activity of selected natural sweeteners available on the Polish market.

    Science.gov (United States)

    Grabek-Lejko, Dorota; Tomczyk-Ulanowska, Kinga

    2013-01-01

    Seventeen natural sweeteners available on the Polish market were screened for total phenolic content, by the Folin-Ciocalteu method, and for antioxidant activity, using the ferric reducing antioxidant power (FRAP) assay and the 2,2'-Azinobis (3-ethylbenzthiazoline-6-sulphonic acid) radical cation decolorization assay (ABTS(·+)). In addition, we analyzed antibacterial activities against Staphylococcus aureus strains: both those susceptible and those resistant to methicillin (MRSA). The results of the study showed that total phenolic content, antioxidant activity and antibacterial activity differ widely among different samples of sweeteners. Phenolic content, expressed as a gallic acid equivalent, ranged from 0 mg kg(-1) in white, refined sugar, xylitol and wheat malt syrup to 11.4 g kg(-1) in sugarcane molasses. Antioxidant activity was lowest in refined white sugar, xylitol, brown beet sugar, liquid fructose, and rape honey; it was average in spelt syrup and corn syrup, and highest in sugar cane, beet molasses, date and barley syrups. Despite the great variety of sweeteners, a strong correlation was noted between the concentration of phenolics and antioxidant properties, as determined by the ABTS(·+) method (r = 0.97) and the FRAP assay (r = 0.77). The strongest antibacterial activity was observed in sugarcane molasses, which was lethal to S. aureus strains at 2 and 4% concentrations in medium for susceptible and MRSA strains respectively. Other sweeteners kill bacteria in 6-15% solutions, whereas some did not show any antibacterial activities against S. aureus strains, even at 20% concentrations. Due to their high antioxidant and antibacterial activities, some of the tested sweeteners have potential therapeutic value as supporting agents in antibiotic therapy.

  9. Synergic antibacterial activity of some essential oils from Lamiaceae

    OpenAIRE

    Sh. Fahimi; H Hajimehdipoor; H. Shabanpoor; Bagheri, F.; M. Shekarchi

    2015-01-01

    Background and objectives: Despite the vast production of new antibiotics in the last three decades, resistance to these drugs by microorganisms has increased and essential oils (EOs) have been recognized to possess antimicrobial properties. Methods:  In the present study, EOs obtained from aerial parts of Thymus vulgaris L., Lavandula angustifolia Mill., Rosmarinus officinalis L. and Mentha piperita L., were evaluated for their single and binary combined antibacterial activities against four...

  10. Synthesis and Antibacterial Activity of New Tetracyclic Triazolothiadiazino Fluoroquinolones

    Institute of Scientific and Technical Information of China (English)

    Guo Qiang HU; Zhong Quan ZHANG; Wen Long HUANG; Hui Bin ZHANG; Sheng Tang HUANG

    2004-01-01

    A series of novel 9-fluoro-10-(4-methylpiperazin-1-yl)-3-substituted-8-oxo-8H-[1,2,4] triazolo[3,4-b]thiadiazino[6,5,4-ij]quinoline-7-carboxylic acids was prepared by a facile synthetic method and the in vitro antibacterial activity against Gram-postive (G+) and Gram negative (G-) bacteria was primarily evaluated.

  11. Gramicidin D enhances the antibacterial activity of fluoride

    OpenAIRE

    Nelson, James W.; ZHOU, ZHIYUAN; Breaker, Ronald R.

    2014-01-01

    Fluoride is a toxic anion found in many natural environments. One of the major bacterial defenses against fluoride is the cell envelope, which limits passage of the membrane-impermeant fluoride anion. Accordingly, compounds that enhance the permeability of bacterial membranes to fluoride should also enhance fluoride toxicity. In this study, we demonstrate that the pore-forming antibiotic gramicidin D increases fluoride uptake in B. subtilis and that the antibacterial activity of this compound...

  12. Synthesis and Antibacterial Activity of Chalcones and Pyrimidine-2-ones

    OpenAIRE

    2005-01-01

    Some new chalcones have been prepared by Claisen-schmidt condensation of ketone and different aromatic aldehydes. These chalcones on condensation with urea in presence of acid gave Pyrimidine-2-ones. The synthesized compounds have been characterized by elemental analysis, IR and 1H NMR spectral data. They have been screened for their antibacterial activity against Gram positive bacteria B. subtillis & S. aureus and Gram negative bacteria E. coli & S. typhi.

  13. ANTIBACTERIAL ACTIVITY OF COMBINATION DRUGS FOR TREATING VAGINOSIS DIFFERENT ETIOLOGIES

    OpenAIRE

    Bobritskaya L.A.; Osolodchenko T. P; Ruban E. A.

    2014-01-01

    Investigated the antimicrobial activity of the combination preparation in capsules "Meraflam" clinical of microbial strains isolated from patients with bacterial vaginosis . Experimentally proved the therapeutic dose of 0.3 g ornidazole in combination with Flamini 0.05 g, improve tolerability and expand the range of antibacterial action of the drug. In view of the antimicrobial capacity of diclofenac sodium from the combination of ofloxacin proposed for use in an in...

  14. Trends and exceptions of physical properties on antibacterial activity for Gram-positive and Gram-negative pathogens.

    Science.gov (United States)

    Brown, Dean G; May-Dracka, Tricia L; Gagnon, Moriah M; Tommasi, Ruben

    2014-12-11

    To better understand the difficulties surrounding the identification of novel antibacterial compounds from corporate screening collections, physical properties of ∼3200 antibacterial project compounds with whole cell activity against Gram-negative or Gram-positive pathogens were profiled and compared to actives found from high throughput (HTS) screens conducted on both biochemical and phenotypic bacterial targets. The output from 23 antibacterial HTS screens illustrated that when compared to the properties of the antibacterial project compounds, the HTS actives were significantly more hydrophobic than antibacterial project compounds (typically 2-4 log units higher), and furthermore, for 14/23 HTS screens, the average clogD was higher than the screening collection average (screening collection clogD = 2.45). It was found that the consequences of this were the following: (a) lead identification programs often further gained hydrophobic character with increased biochemical potency, making the separation even larger between the physicochemical properties of known antibacterial agents and the HTS active starting point, (b) the probability of plasma protein binding and cytotoxicity are often increased, and (c) cell-based activity in Gram-negative bacteria was severely limited or, if present, demonstrated significant efflux. Our analysis illustrated that compounds least susceptible to efflux were those which were highly polar and small in MW or very large and typically zwitterionic. Hydrophobicity was often the dominant driver for HTS actives but, more often than not, precluded whole cell antibacterial activity. However, simply designing polar compounds was not sufficient for antibacterial activity and pointed to a lack of understanding of complex and specific bacterial penetration mechanisms.

  15. Parasiticidal, antifungal and antibacterial activities of Onosma ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-05

    Oct 5, 2009 ... Onosma griffithii was screened for possible pharmacological activities. The crude ... Based on the IC 50 values, the potency of the standard drug (Pentamidine) and test fractions were ... Similarly, anticancer activity of. Onosma ...

  16. Study on antibacterial activity of hydrogel from irradiated silk protein

    Energy Technology Data Exchange (ETDEWEB)

    Bunnak, J.; Chaisupakitsin, M. [King Mongkut' s Institute of Technology Lardkrabang, Bangkok (Thailand)

    2001-03-01

    Hydrogels for biomedical application were prepared from solution blends of 3% silk protein and 3%, 10% poly (vinyl alcohol) (PVA) and followed with irradiation. Mixture of hydrogels were gamma irradiated at 10, 20, 30, 40 and 50 kGy under N{sub 2} atmosphere. To clarify anti-bacterial activity of hydrogels, modified of the Agar disk diffusion method and American Association of Textile Chemists and Colorists, AATCC Test Method 90-1977, were carried out. The four kinds of bacteria such as Escherichia coli, Bacillus subtilis, Staphylococcus aureus and Staphylococcus epidermidis, were used. It was found that a 1:3 volume ratio of 3% silk protein and 3% PVA respectively, at 50 kGy irradiation, is suitable conditions for preparation hydrogels and trend to indicate the highest of an antibacterial activity against E. coli, B. subtilis and S. aureus. However the antibacterial activity of hydrogels against S. epidermidis was not clearly. These results are very useful to expand the application of hydrogel from irradiated silk protein to the medical products. (author)

  17. Antiproliferative and antibacterial activity of some glutarimide derivatives.

    Science.gov (United States)

    Popović-Djordjević, Jelena B; Klaus, Anita S; Žižak, Željko S; Matić, Ivana Z; Drakulić, Branko J

    2016-12-01

    Antiproliferative and antibacterial activities of nine glutarimide derivatives (1-9) were reported. Cytotoxicity of compounds was tested toward three human cancer cell lines, HeLa, K562 and MDA-MB-453 by MTT assay. Compound 7 (2-benzyl-2-azaspiro[5.11]heptadecane-1,3,7-trione), containing 12-membered ketone ring, was found to be the most potent toward all tested cell lines (IC50 = 9-27 μM). Preliminary screening of antibacterial activity by a disk diffusion method showed that Gram-positive bacteria were more susceptible to the tested compounds than Gram-negative bacteria. Minimum inhibitory concentration (MIC) determined by a broth microdilution method confirmed that compounds 1, 2, 4, 6-8 and 9 inhibited the growth of all tested Gram-positive and some of the Gram-negative bacteria. The best antibacterial potential was achieved with compound 9 (ethyl 4-(1-benzyl-2,6-dioxopiperidin-3-yl)butanoate) against Bacillus cereus (MIC 0.625 mg/mL; 1.97 × 10(-3 )mol/L). Distinction between more and less active/inactive compounds was assessed from the pharmacophoric patterns obtained by molecular interaction fields.

  18. Antibacterial Activity of Neat Chitosan Powder and Flakes.

    Science.gov (United States)

    Ardila, Nury; Daigle, France; Heuzey, Marie-Claude; Ajji, Abdellah

    2017-01-06

    This study investigates the antibacterial activity of neat chitosan powder and flakes against three different bacterial species, Escherichia coli, Listeria innocua and Staphylococcus aureus, which are frequent causes of food spoilage. The effect of chitosan concentration and purity, as well as the influence of temperature, ionic strength (salt) and impact of a solid physical support in the medium are examined. Results show that the antibacterial activity of neat chitosan: (i) requires partial solubilisation; (ii) can be promoted by environmental factors such as adequate temperature range, ionic strength and the presence of a solid physical support that may facilitate the attachment of bacteria; (iii) depends on bacterial species, with a sensitivity order of E. coli > L. innocua > S. aureus; and (iv) increases with chitosan concentration, up to a critical point above which this effect decreases. The latter may be due to remaining proteins in chitosan acting as nutrients for bacteria therefore limiting its antibacterial activity. These results on the direct use of chitosan powder and flakes as potential antimicrobial agents for food protection at pH values lower than the chitosan pKa (6.2-6.7) are promising.

  19. Screening of solvent dependent antibacterial activity of Prunus domestica.

    Science.gov (United States)

    Yaqeen, Zahra; Naqvi, Naim-ul-Hasan; Sohail, Tehmina; Rehman, Zakir-ur; Fatima, Nudrat; Imran, Hina; Rehman, Atiqur

    2013-03-01

    Fruit of Prunus domestica was extracted in ethanol. The ethanol extract was further extracted with two solvents ethyl acetate and chloroform. The crude ethanol extract and two fractions (ethyl acetate and chloroform) were screened for their antibacterial activity using the agar well diffusion method .They were tested against nine bacteria; five Gram positive bacteria (Staphylococcus aureus, Streptococcuc intermedius, Bacillus cereus, Bacillus pumilus) and four Gram negative bacteria (Eschrichia coli, Proteus mirabilis Shigella flexneri, Salmonella typhi and Klebsiela pneumoniae). The susceptibility of microorganisms to all three fractions was compared with each other and with standard antibiotic (Ampicillin) Among all fractions ethyl acetate exhibited highest antibacterial activity (average zone of inhibition 34.57mm ± 1.3) while ethyl alcohol exhibited least antibacterial activity (average zone of inhibition 17.42mm ± 3.3). Minimum inhibitory concentration of ethanol, ethyl acetate and chloroform fractions was found in the range of 78 μ g/ml to 2500 μ gl/ml against gram positive and gram negative bacteria.

  20. Facile synthesis of novel benzotriazole derivatives and their antibacterial activities

    Indian Academy of Sciences (India)

    Jun Wan; Peng-Cheng Lv; Na-Na Tian; Hai-Liang Zhu

    2010-07-01

    A series of benzotriazole derivatives (compounds 1-27) were synthesized, and 24 (compounds 1-5, 9-27) of which were first reported. Their chemical structures were confirmed by means of 1H NMR, IR and elemental analyses, coupled with one selected single crystal structure (compound 1). All the compounds were assayed for antibacterial activities against three Gram positive bacterial strains (Bacillus subtilis, Staphylococcus aureus and Streptococcus faecalis) and three Gram negative bacterial strains (Escherichia coli, Pseudomonas aeruginosa and Enterobacter cloacae) by MTT method. Among the compounds tested, most of them exhibited potent antibacterial activity against the six bacterial strains. Most importantly, compound 3-benzotriazol-1-yl-1-(4-bromo-phenyl)-2-[1,2,4]triazol-1-ylpropan-1-one (19) showed the most favourable antibacterial activity against B. subtilis, S. aureus, S. faecalis, P. aeruginosa, E. coli and E. cloacae with MIC of 1.56 g/mL, 1.56 g/mL, 1.56 g/mL, 3.12 g/mL, 6.25 g/mL and 6.25 g/mL, respectively.

  1. Antibacterial activities of serum from the Komodo Dragon (Varanus komodoensis

    Directory of Open Access Journals (Sweden)

    Mark Merchant

    2013-07-01

    Full Text Available Komodo dragons (Varanus komodoensis are able to feed on large prey items by injecting a dose of toxic bacteria with their bite that, over time, kills the prey by systemic infection. Dragons also suffer bites from other members of their own species during territorial disputes and feeding frenzies. However, they do not suffer the same fate as their prey, suggesting that they have developed a strong immunity to bacterial infections. This study was undertaken to determine the antibacterial activities of serum from the Komodo dragon. Bacterial cultures were treated with different volumes serum from Varanus komodoensis and the growth was monitored by optical density at 430 nm. In addition, the serum was treated with protease, chelators of divalent metal ions, or with mild heat to determine the mechanism of antibacterial activities. Treatment of bacterial cultures with serum from Komodo dragons (Varanus komodoensis resulted in a volume-dependent decrease in bacterial growth. Cultures of Escherichia coli, Staphylococcus aureus, and Klebsiella oxytoca exhibited moderate-strong growth inhibition by V. komodoensis serum, while cultures of Streptococcus epidermitis, Salmonella typhimurium, Providencia stuartii, and Shigella flexneri were nearly completely obliterated for 24 h by only 10% (v/v serum. The antibacterial activity of V. komodensis serum occurred very rapidly, as 18% of E. coli growth was inhibited by a five min exposure to serum. Furthermore, 10- and 20-min incubations of E. coli with serum from V. komodoensis resulted in 43 and 68% inhibition of bacterial growth, respectively. The bactericidal capacity of the serum against E. coli was 2,075,000 bacteria/μL serum, and was inhibited by mild heat treatment, pronase, EDTA, and phosphate, indicating that the anti-bacterial action is most probably due to the presence of a potent serum complement protein system.

  2. Synthesis and comparing the antibacterial activities of pyrimidine derivatives

    Indian Academy of Sciences (India)

    B ANDREWS; K KOMATHI; S MOHAN

    2017-03-01

    A series of 10 derivatives of 5-(5-amino-1,3,4-thiadiazole-2-yl)-3,4-dihydro-6-methyl-4-phenylpyrimidin-2(1H)-one and 10 derivatives of 3,4-dihydro-5-(5-mercapto-4H-1,2,4-triazol-3-yl)-6-methyl-4-phenyl pyrimidin-2(1H)-one have been synthesized. Among the synthesized derivatives, triazole substitutedcompounds have shown higher antibacterial inhibition when compared to the thiadiazole derivatives. All the structures of the newly synthesized compounds have been characterized by IR, 1H and 13C NMR, GC-MS and CHN analysis. Most of the compounds have shown promising antibacterial activity when compared with the standard drug ciprofloxacin.

  3. Synthesis of novel bisindolylmethane Schiff bases and their antibacterial activity.

    Science.gov (United States)

    Imran, Syahrul; Taha, Muhammad; Ismail, Nor Hadiani; Khan, Khalid Mohammed; Naz, Farzana; Hussain, Memona; Tauseef, Saima

    2014-08-06

    In an effort to develop new antibacterial drugs, some novel bisindolylmethane derivatives containing Schiff base moieties were prepared and screened for their antibacterial activity. The synthesis of the bisindolylmethane Schiff base derivatives 3-26 was carried out in three steps. First, the nitro group of 3,3'-((4-nitrophenyl)-methylene)bis(1H-indole) (1) was reduced to give the amino substituted bisindolylmethane 2 without affecting the unsaturation of the bisindolylmethane moiety using nickel boride in situ generated. Reduction of compound 1 using various catalysts showed that combination of sodium borohydride and nickel acetate provides the highest yield for compound 2. Bisindolylmethane Schiff base derivatives were synthesized by coupling various benzaldehydes with amino substituted bisindolylmethane 2. All synthesized compounds were characterized by various spectroscopic methods. The bisindolylmethane Schiff base derivatives were evaluated against selected Gram-positive and Gram-negative bacterial strains. Derivatives having halogen and nitro substituent display weak to moderate antibacterial activity against Salmonella typhi, S. paratyphi A and S. paratyphi B.

  4. CHITOSAN: ANTIBACTERIAL ACTIVITY AND PERSPECTIVES OF THE BIOMEDICAL APPLICATION

    Directory of Open Access Journals (Sweden)

    Sukhodub L.B.

    2014-10-01

    Full Text Available In the last decades, serious attention is attracted by the use of natural antimicrobial drugs instead of the usual ones because of pathogens resistance to antibiotics. Chitosan (CS is widely used as an antimicrobial agent owing to its high biodegradability, nontoxicity and antimicrobial properties. CS is a cationic polysaccharide obtained by partial deacetylation of chitin, the major component of crustacean shells. In last time cultivation of fungi provides an alternative source of the CS obtaining: Chitin makes up 45 % of the A. niger and M. rouxii cell wall content and up to 20 % of the P. notatum cell wall content In contrast to other polymers, chitosan is a hydrophilic polymer with positive charge and has three types of functional groups: amino group at position C-2 in each deacetylated structural unit, as well as primary and secondary hydroxyl groups at C-6 and C-3 positions respectively. This causes its ability to form new hydrofilic medicals on the basis of known drugs, as well as the formation of drug release systems. CS is unique adsorbent and it is possible to combine it with another drugs. The natural ability of CS for gelation is used in the preparation of the hemostatic agent "Celox", that is effective for preventing fatalities when arterial bleeding occurs on the battlefield. The clotting of "Celox" occurs much faster than other hemostatic agents. Antimicrobial activity of chitosan against many Gram-positive and Gram-negative bacteria, filamentous fungi and yeasts has been widely demonstrated in the scientific literature.There are some reported mechanisms for antibacterial activity: positively charged due to NH3+ groups Chitosan interact with negatively charged functional groups at the cell surface and compromise the cell wall or outer membrane. In the case of Gram-positive bacteria, lipoteichoic acid could provide a molecular linkage for chitosan at the cell surface, allowing it to disturb membrane functions. Lipopolysaccharides

  5. Antibacterial flame retardant cotton high loft nonwovens

    Science.gov (United States)

    Renewable resources for raw materials and biodegradability of the product at the end of the useful life is entailing a shift from petroleum-based synthetics to agro based natural fibers such as cotton, especially for producing high specific volume high loft nonwovens. Cotton is highly flammable and ...

  6. Antibacterial activity of papain and bromelain on Alicyclobacillus spp.

    Science.gov (United States)

    dos Anjos, Márcia Maria; da Silva, Angela Aparecida; de Pascoli, Isabela Carolini; Mikcha, Jane Martha Graton; Machinski, Miguel; Peralta, Rosane Marina; de Abreu Filho, Benício Alves

    2016-01-04

    Alicyclobacillus spp. are spore forming bacteria that are often related to the deterioration of acidic products such as beverages and citrus juices. After the process of industrial pasteurization, the spore produced by the bacteria can germinate and the microorganism can grow, causing sensory abnormalities in the product. Alternative biopreservatives, such as the antimicrobial compounds, are of considerable importance to the food industry. Papain and bromelain are proteolytic enzymes derived frompapaya and pineapple, respectively. These enzymes are widely used in medicine and in the pharmaceutical and food industries, but while some studies have described their antibacterial action, no studies of the Alicyclobacillus spp. exist. The aimof this studywas to analyze the antibacterial effect of papain and bromelain on Alicyclobacillus spp. through 1) determining minimum inhibitory and bactericidal concentration (MIC and MBC); 2) determining the death time curve of the micro-organism in the presence and absence of enzymes; and 3) investigating the enzymatic mechanism on the microorganism. The antibacterial activity of enzymes in combination with nisin was also evaluated. The results showed that for the Alicyclobacillus acidoterrestris strain, the MIC of papain was 0.98 μg/mL and the MBC was 3.91 μg/mL, while theMIC of bromelain was 62.5 μg/mL and the MBCwas 250 μg/mL. The concentration of 4 ×MIC for both the enzymes was sufficient to eliminate 4 logs of the micro-organism after 24 h of incubation. Through the use of enzyme inhibitors specific for cysteine proteases, it was found that the antibacterial activity of papain and bromelain is not related to its proteolytic activity, butmay be related to other activities, such as amidse and esterase. The synergistic activity of the enzymes revealed a fractional inhibitory concentration (FIC) level of 0.16. Combination with nisin revealed an FIC of 0.25 for papain and 0.19 for bromelain, indicating synergism between both

  7. Synthesis and antibacterial activity of aminosugar-functionalized intercalating agents.

    Science.gov (United States)

    Shi, Wei; Marcus, Sandra L; Lowary, Todd L

    2010-01-11

    A series of previously reported amino sugar-functionalized intercalating agents, 3-14, were evaluated in two antibacterial assays (paper disk diffusion and 96-well microdilution) against Bacillus atrophaeus, ATCC 9372 and Escherichia coli, ATCC 47076. Although none of the compounds were active against this E. coli strain, several showed activity against B. atrophaeus. In anticipation of the need for larger amounts of these compounds for future structure-activity relationship studies, improved routes to 11-14 were developed. Copyright 2009 Elsevier Ltd. All rights reserved.

  8. EVALUATION OF ANTIBACTERIAL ACTIVITIES OF NOVEL AZIRIDINYL PHOSPHONATES

    Directory of Open Access Journals (Sweden)

    Assia Keniche

    2016-05-01

    Full Text Available A new series of aziridines was synthesized in our laboratory, which displays potent antibiotic activities. However, a practical synthesis by using the coupling method of this aziridines with either phosphonate or N-phtaloyl acide moiety can be converted into various derivatives. This work describes new results of our ongoing research targeting new derivatives of biological interest. All the compounds were screened for their antibacterial activity, they all showed comparable moderate to good growth inhibitory activity with reference to Tetracyclin and Gentamicin.

  9. Antibacterial Activities of Wasabi against Escherichia coli O157:H7 and Staphylococcus aureus

    Science.gov (United States)

    Lu, Zhongjing; Dockery, Christopher R.; Crosby, Michael; Chavarria, Katherine; Patterson, Brett; Giedd, Matthew

    2016-01-01

    Escherichia coli O157:H7 and Staphylococcus aureus are two of the major pathogens frequently involved in foodborne outbreaks. Control of these pathogens in foods is essential to food safety. It is of great interest in the use of natural antimicrobial compounds present in edible plants to control foodborne pathogens as consumers prefer more natural “green” foods. Allyl isothiocyanate (AITC) is an antimicrobial compound naturally present in wasabi (Japanese horseradish) and several other edible plants. Although the antibacterial effects of pure AITC and wasabi extract (essential oil) against several bacteria have been reported, the antibacterial property of natural wasabi has not been well studied. This study investigated the antibacterial activities of wasabi as well as AITC against E. coli O157:H7 and S. aureus. Chemical analysis showed that AITC is the major isothiocyanate in wasabi. The AITC concentration in the wasabi powder used in this study was 5.91 ± 0.59 mg/g. The minimum inhibitory concentration (MIC) of wasabi against E. coli O157:H7 or S. aureus was 1% (or 10 mg/ml). Wasabi at 4% displayed higher bactericidal activity against S. aureus than against E. coli O157:H7. The MIC of AITC against either pathogen was between 10 and 100 μg/ml. AITC at 500 μg/ml was bactericidal against both pathogens while AITC at 1000 μg/ml eliminated E. coli O157:H7 much faster than S. aureus. The results from this study showed that wasabi has strong antibacterial property and has high potential to effectively control E. coli O157:H7 and S. aureus in foods. The antibacterial property along with its natural green color, unique flavor, and advantage to safeguard foods at the point of ingestion makes wasabi a promising natural edible antibacterial plant. The results from this study may be of significant interest to the food industry as they develop new and safe foods. These results may also stimulate more research to evaluate the antibacterial effect of wasabi against other

  10. Preparation of graphene oxide-silver nanoparticle nanohybrids with highly antibacterial capability.

    Science.gov (United States)

    Zhu, Zhijun; Su, Min; Ma, Lan; Ma, Lina; Liu, Dianjun; Wang, Zhenxin

    2013-12-15

    A simple method based on electrostatic interactions was utilized to assemble silver nanoparticles (AgNPs) to graphene oxide (GO) sheets. This method allows conjugation of AgNPs with desired morphologies (densities, sizes and shapes) onto GO. In this process, poly(diallyldimethylammonium chloride) (PDDA) was introduced as an adhesive agent. The as-prepared graphene oxide-AgNPs composites (GO-AgNPs) have enhanced colloid stability and photo-stability than that of AgNPs. After conjugating to GO sheets, the antibacterial activities of AgNPs against Gram negative (G-) bacterial strain (Escherichia coli, E. coli) and Gram positive (G+) bacterial strain (Bacillus subtilis, B. subtilis) have been improved significantly. The antibacterial activity of GO-AgNPs is dependent on the size of AgNPs, i.e. the small AgNPs modified GO sheets show more effective antibacterial capability than that of large AgNPs modified GO sheets. Compared with AgNPs, the enhanced antibacterial activity of GO-AgNPs might not only be due to high stability of AgNPs anchored on GO sheets, but also the positive charged surface of hybrids which increases the electrostatic interaction of bacterial cell membrane with nanohybrids.

  11. Comparative study of hypoglycemic and antibacterial activity of organic extracts of four Bangladeshi plants

    Institute of Scientific and Technical Information of China (English)

    Mohammad Shah Hafez Kabir; Shabbir Ahmad; Md. Sofi Mahamoud; Nishan Chakrabarty; Md.Akramul Hoque; Mohammed Munawar Hossain; Md.Nazim Uddin Chy; Mohammed Shoibe

    2016-01-01

    Objective:To examine hypoglycemic and antibacterial activity against some Gram-positive and Gram-negative bacteria of organic extracts of four Bangladeshi plants. Methods:Anin vivo hypoglycemic effect on mice model was used to check the hypoglycemic effect of four Bangladeshi herbal organic extractsviz., roots ofCurculigo recurvata W. T. Aiton (Satipata) (C. recurvata), leaf ofAmorphophallus bulbiferRoxb. (Olkachu) (A. bulbifer), whole plant ofThunbergia grandiflora Roxb. (Nillata) (T. grandiflora) and leaf ofSteudnera colocasiifolia K. Koch (Yunnan) (S. colocasiifolia) using glibenclamide as a positive control and water as a negative control. They were also tested for antibacterial activity on three Gram-positive and four Gram-negative bacteria by disk diffusion method.C. recurvata,A. bulbifer andT. grandiflora were extracted with methanol andS. colocasiifolia was extracted with ethanol. Results:Among all the plant extract, only ethanol extract ofS. colocasiifolia leaves at 800 mg/kg dose significantly (P Conclusions: Through our study, it was found thatS. colocasiifolia could be considered as very promising and beneficial hypoglycemic agent. AlthoughC. recurvata andS. colocasiifolia showed comparable high antibacterial activity, further studies should be needed to develop new antibacterial agent from them.S. colocasiifolia may be a potential source for the development of new oral hypoglycemic agent.

  12. In vitro antibacterial activity of Hibiscus rosa-sinensis flower extract against human pathogens

    Institute of Scientific and Technical Information of China (English)

    Ruban P; Gajalakshmi K

    2012-01-01

    Objective: To access the in vitro antibacterial activity of Hibiscus rosa-sinensis (H. rosa- sinensis) flower extract against human pathogens. Methods: Antibacterial activity was evaluated by using disc and agar diffusion methods. The protein was run through poly acrylmide gel electrophoresis to view their protein profile. Results: The results showed that the cold extraction illustrates a maximum zone of inhibition against Bacillus subtillis (B. subtillis), Escherichia coli (E. coli) viz., (17.00 ± 2.91), (14.50 ± 1.71) mm, followed by hot extraction against, E. coli, Salmonella sp. as (11.66 ± 3.14), (10.60 ± 3.09) mm. In methanol extraction showed a highest zone of inhibition recorded against B. subtillis, E. coli as (18.86 ± 0.18), (18.00 ± 1.63) mm pursued by ethanol extraction showed utmost zone of inhibition recorded against Salmonella sp. at (20.40 ± 1.54) mm. The crude protein from flower showed a maximum inhibitory zone observed against Salmonella sp., E. coliviz., (16.55 ± 1.16), (14.30 ± 2.86) mm. The flower material can be taken as an alternative source of antibacterial agent against the human pathogens. Conclusions: The extracts of the H. rosa-sinensis are proved to have potential antibacterial activity, further studies are highly need for the drug development.

  13. Antibacterial activity of crude extracts from Mexican medicinal plants and purified coumarins and xanthones.

    Science.gov (United States)

    Yasunaka, Kakuko; Abe, Fumiko; Nagayama, Ariaki; Okabe, Hikaru; Lozada-Pérez, Lucio; López-Villafranco, Edith; Muñiz, Elizabeth Estrada; Aguilar, Abigail; Reyes-Chilpa, Ricardo

    2005-02-28

    Thirty-two extracts from 22 Mexican medicinal plants of 15 different families were assayed to determine their antibacterial activity against Escherichia coli and Staphylococcus aureus. Seventeen plants showed antibacterial activity, while five plants showed no activity against both bacteria. All of the extracts showed higher activity against Staphylococcus aureus (methicillin-sensitive and methicillin-resistant) than against Escherichia coli, except one. Among the plants examined, Bursera simaruba (L.) Sarg. (Burseraceae), Haematoxylum brasiletto H. Karst. (Fabaceae), Calophyllum brasiliense Cambess. (Clusiaceae), and Mammea americana L. (Clusiaceae) were highly active against Staphylococcus aureus. Coumarins (mammea A/BA and mammea A/AA) and xanthones, namely jacareubin and 1,3,5,6-tetrahydroxy-2-(3,3-dimethylallyl) xanthone, were isolated as the principle compounds from the last two plants.

  14. Antibacterial, antifungal and cytotoxic activity of terrestrial cyanobacterial strains from Serbia

    Institute of Scientific and Technical Information of China (English)

    Zorica SVIRCEV; Dragana CETOJEVIC-SIMIN; Jelica SIMEUNOVIC; Maja KARAMAN; Dejan STOJANOVIC

    2008-01-01

    Cyanobacteria are known to be a rich source of biologically active compounds some of which can have pharmaceutical importance. In this work we present the screening results of cyanobacterial strains for their antibacterial, antifungal, and cytotoxic activity. Cyanobacterial strains were isolated from various soil types in province of Vojvodina and Central Serbia, Republic of Serbia. The screening included 9 strains of Anabaena and 9 strains of Nostoc. Both, extracellular products (from the culture liquid) and cellular crude Iipophilic extracts were tested against 13 bacterial strains and 8 fungal strains. Cytotoxic activity was tested against three human cell lines. Methanol extracts were prepared according to φstensvik. Antibacterial and antifungal activities were determined measuring inhibition zone, 48 h after inoculation. The cytotoxic activity was determined by suIforhodamine B (SRB) colorimetric assay. Of all cyanobacterial strains tested, 52% showed some antifungal and 41% antibacterial activity. Two out of six tested strains possessed cytotoxic activity. The cytotoxic activity of Anabaena strain S12 was found both in culture liquid and crude cell extract. It occurred specifically between the 21st and 42nd day of cultivation against HeLa and MCF7 cells, but had no activity against cell line derived from a healthy tissue. A high percentage of the active strains among the tested strains justify the effort of screening cyanobacteria that are isolated from terrestrial environments. The most promising strains for the fur-ther study are Anabaena strain S12 which showed strong cytotoxic and antibacterial activity and Ana-baena strain S20 which produces a potent antifungal compound. The future work, besides further screening and chemical identification of the active compounds, should also include the development of culture techniques that would lead to more efficient production of biologically active compounds.

  15. Antibacterial, antifungal and cytotoxic activity of terrestrial cyanobacterial strains from Serbia

    Institute of Scientific and Technical Information of China (English)

    Zorica; SVIRCEV; Dragana; CETOJEVIC-SIMIN; Jelica; SIMEUNOVIC; Maja; KARAMAN; Dejan; STOJANOVIC

    2008-01-01

    Cyanobacteria are known to be a rich source of biologically active compounds some of which can have pharmaceutical importance. In this work we present the screening results of cyanobacterial strains for their antibacterial, antifungal, and cytotoxic activity. Cyanobacterial strains were isolated from various soil types in province of Vojvodina and Central Serbia, Republic of Serbia. The screening included 9 strains of Anabaena and 9 strains of Nostoc. Both, extracellular products (from the culture liquid) and cellular crude lipophilic extracts were tested against 13 bacterial strains and 8 fungal strains. Cytotoxic activity was tested against three human cell lines. Methanol extracts were prepared according to ?stensvik. Antibacterial and antifungal activities were determined measuring inhibition zone, 48 h after inoculation. The cytotoxic activity was determined by sulforhodamine B (SRB) colorimetric assay. Of all cyanobacterial strains tested, 52% showed some antifungal and 41% antibacterial activity. Two out of six tested strains possessed cytotoxic activity. The cytotoxic activity of Anabaena strain S12 was found both in culture liquid and crude cell extract. It occurred specifically between the 21st and 42nd day of cultivation against HeLa and MCF7 cells, but had no activity against cell line derived from a healthy tissue. A high percentage of the active strains among the tested strains justify the effort of screening cyanobacteria that are isolated from terrestrial environments. The most promising strains for the fur- ther study are Anabaena strain S12 which showed strong cytotoxic and antibacterial activity and Ana- baena strain S20 which produces a potent antifungal compound. The future work, besides further screening and chemical identification of the active compounds, should also include the development of culture techniques that would lead to more efficient production of biologically active compounds.

  16. STUDIES ON THE PREPARATION OF ZINC-CONTAINING ACTIVATED CARBON FIBERS AND THEIR ANTIBACTERIAL ACTIVITY

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Several kinds of activated carbon fibers, using sisal fiber as precursors, were preparedwith steam activation or with ZnCl2 activation. Zinc or its compounds were dispersed in them. Theantibacterial activities of these activated carbon fibers were determined and compared. The researchresults showed that these sisal based activated carbon fibers supporting zinc have strongerantibacterial activity against Escherichia coli and S. aureus. The antibacterial activity is related tothe precursors, the pyrolysis temperature, and the zinc content. In addition, small quantity of silversupported on zinc-containing ACFs will greatly enhance the antibacterial activity of ACFs.

  17. Development of Silver Ion Doped Antibacterial Clays and Investigation of Their Antibacterial Activity

    OpenAIRE

    Karel, Filiz B.; Ali S. Koparal; Elif Kaynak

    2015-01-01

    Kaolinite, sepiolite, and clinoptilolite were used as carriers to develop antibacterial materials. The materials were enriched in sodium by ion exchange. Silver ion exchange by silver nitrate followed by phosphoric acid treatment enabled the controlled release of silver. The antibacterial function of the materials was investigated by halo test and the amount of silver released was investigated by energy dispersive X-ray spectroscopy. The enhanced antibacterial efficiency was obtained by minim...

  18. A novel short anionic antibacterial peptide isolated from the skin of Xenopus laevis with broad antibacterial activity and inhibitory activity against breast cancer cell.

    Science.gov (United States)

    Li, Siming; Hao, Linlin; Bao, Wanguo; Zhang, Ping; Su, Dan; Cheng, Yunyun; Nie, Linyan; Wang, Gang; Hou, Feng; Yang, Yang

    2016-07-01

    A vastarray of bioactive peptides from amphibian skin secretions is attracting increasing attention due to the growing problem of bacteria resistant to conventional antibiotics. In this report, a small molecular antibacterial peptide, named Xenopus laevis antibacterial peptide-P1 (XLAsp-P1), was isolated from the skin of Xenopus laevis using reversed-phase high-performance liquid chromatography. The primary structure of XLAsp-P1, which has been proved to be a novel peptide by BLAST search in AMP database, was DEDDD with a molecular weight of 607.7 Da analysed by Edman degradation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/TOF-MS). The highlight of XLAsp-P1 is the strong in vitro potency against a variety of Gram-positive and Gram-negative bacteria with minimum inhibitory concentrations (MICs) starting at 10 μg/mL and potent inhibitory activity against breast cancer cell at tested concentrations from 5 to 50 μg/mL. In addition, only 6.2 % of red blood cells was haemolytic when incubated with 64 μg/mL (higher than MICs of all bacterial strain) of XLAsp-P1. The antimicrobial mechanism for this novel peptide was the destruction of the cell membrane investigated by transmission electron microscopy. All these showed that XLAsp-P1 is a novel short anionic antibacterial peptide with broad antibacterial activity and inhibitory activity against breast cancer cell.

  19. Negatively charged silver nanoparticles with potent antibacterial activity and reduced toxicity for pharmaceutical preparations

    Directory of Open Access Journals (Sweden)

    Salvioni L

    2017-03-01

    Full Text Available Lucia Salvioni,1 Elisabetta Galbiati,1 Veronica Collico,1 Giulia Alessio,1 Svetlana Avvakumova,1 Fabio Corsi,2,3 Paolo Tortora,1 Davide Prosperi,1 Miriam Colombo1 1Nanobiolab, Department of Biotechnology and Bioscience, University of Milano-Bicocca, 2Biological and Clinical Science Department, University of Milan, Milano, 3Surgery Department, Breast Unit, IRCCS S Maugeri Foundation, Pavia, Italy Background: The discovery of new solutions with antibacterial activity as efficient and safe alternatives to common preservatives (such as parabens and to combat emerging infections and drug-resistant bacterial pathogens is highly expected in cosmetics and pharmaceutics. Colloidal silver nanoparticles (NPs are attracting interest as novel effective antimicrobial agents for the prevention of several infectious diseases.Methods: Water-soluble, negatively charged silver nanoparticles (AgNPs were synthesized by reduction with citric and tannic acid and characterized by transmission electron microscopy, dynamic light scattering, zeta potential, differential centrifuge sedimentation, and ultraviolet–visible spectroscopy. AgNPs were tested with model Gram-negative and Gram-positive bacteria in comparison to two different kinds of commercially available AgNPs.Results: In this work, AgNPs with higher antibacterial activity compared to the commercially available colloidal silver solutions were prepared and investigated. Bacteria were plated and the antibacterial activity was tested at the same concentration of silver ions in all samples. The AgNPs did not show any significant reduction in the antibacterial activity for an acceptable time period. In addition, AgNPs were transferred to organic phase and retained their antibacterial efficacy in both aqueous and nonaqueous media and exhibited no toxicity in eukaryotic cells.Conclusion: We developed AgNPs with a 20 nm diameter and negative zeta potential with powerful antibacterial activity and low toxicity compared

  20. Bismuth subsalicylate nanoparticles with anaerobic antibacterial activity for dental applications

    Science.gov (United States)

    Vega-Jiménez, A. L.; Almaguer-Flores, A.; Flores-Castañeda, M.; Camps, E.; Uribe-Ramírez, M.; Aztatzi-Aguilar, O. G.; De Vizcaya-Ruiz, A.

    2017-10-01

    In recent years, nanomaterials have been used in the medical-dental field as new alternative antimicrobial agents. Bismuth subsalicylate (BSS) has been used as an antimicrobial agent, but the effect of BSS in the form of nanoparticles (BSS-nano) as a potential antimicrobial agent has not been tested, in specific against bacteria responsible for periodontal disease. The aim of this study was to evaluate the antibacterial effect of BSS-nano against oral anaerobic bacteria and to assess the safety of BSS-nano by evaluating their cytotoxicity in human gingival fibroblast (HGF-1) cells. BSS-nano were synthesized by laser ablation and were previously physico-chemically characterized using in vitro assays. The antibacterial activity was measured using the tetrazolium-based XTT assay, and cytotoxicity was determined using lactate dehydrogenase (LDH) and MTS assays in HGF-1 cells. Transmission electron microscopy of HGF-1 exposed to BSS-nano was also performed. BSS-nano was shown to have a primary size of 4–22 nm and a polygonal shape. Among the tested bacterial strains, those with a greater sensitivity to BSS-nano (highest concentration of 21.7 μg ml‑1) were A. actinomycetemcomitans, C. gingivalis, and P. gingivalis. BSS-nano at a concentration of 60 μg ml‑1 showed low cytotoxicity (6%) in HFG-1 cells and was mainly localized intracellularly in acidic vesicles. Our results indicate that the concentration of BSS-nano used as an effective antibacterial agent does not induce cytotoxicity in mammalian cells; thus, BSS-nano can be applied as an antibacterial agent in dental materials or antiseptic solutions.

  1. Antibacterial and Antioxidant Activities of Typhonium Flagelliforme (Lodd. Blume Tuber

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    Syam Mohan

    2008-01-01

    Full Text Available Problem Statement: Multiple drug resistance in human pathogenic micro organisms has developed due to indiscriminate use of modern antimicrobial drugs generally used in the management of infectious diseases. This increases the importance of exploiting the natural sources instead modern drugs. Approach: The antibacterial and antioxidant activity of different extracts from of Typhonium flagelliforme (L. Blume tuber (family: Araceae commonly called ‘Rodent Tuber’ was assessed towards selected bacteria as well as in different antioxidant models. The antibacterial screening was carried out by disc diffusion method. Two complementary test systems, namely DPPH free radical scavenging and total phenolic compounds, were used for the antioxidant analysis. Results: Except hexane extract none of the other exacts shown anti bacterial activity against the selected strains. The hexane extract from Typhonium flagelliforme tuber had interesting activity against both the gram negative bacteria, Pseudomonas aeruginosa (11±1.0 mm diameter and Salmonella choleraesuis (12±1.1 mm diameter. The positive control, Streptomycin had shown zone of inhibition of 20±1.5 mm, 20±1.3 mm, 23±1.5 mm and 23±1.0 mm in Methicillin Resistant Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella choleraesuis and Bacillus subtilis respectively. All the extracts were subjected to screening for their possible antioxidant activity. The DPPH assay showed that the inhibitory activity of ethyl acetate (77.6±0.9 % and dichloromethane (70.5±1.7 % extracts were having comparatively admirable inhibition capacity when compared to the positive control BHT (95.3±1.3 %. Total phenolic content of all extracts was also evaluated, and dichloromethane extracts (5.21±0.82 GAE mg/g extract was superior to all other extracts, followed by hexane and ethyl acetate. Conclusion: Considering all the results collectively T. flagelliforme appears to

  2. Antibacterial activity of biochemically capped iron oxide nanoparticles: A view towards green chemistry.

    Science.gov (United States)

    Irshad, Rabia; Tahir, Kamran; Li, Baoshan; Ahmad, Aftab; R Siddiqui, Azka; Nazir, Sadia

    2017-05-01

    A green approach to fabricate nanoparticles has been evolved as a revolutionary discipline. Eco-compatible reaction set ups, use of non-toxic materials and production of highly active biological and photocatalytic products are few benefits of this greener approach. Here, we introduce a green method to synthesize Fe oxide NPs using Punica granatum peel extract. The formation of Fe oxide NPs was optimized using different concentrations of peel extract (20mL, 40mL and 60mL) to achieve small size and better morphology. The results indicate that the FeNPs, obtained using 40mL concentration of peel extract possess the smallest size. The morphology, size and crystallinity of NPs was confirmed by implementing various techniques i.e. UV-Vis spectroscopy, X-ray diffraction, Scanning Electron Microscopy and Electron Diffraction Spectroscopy. The bio-chemicals responsible for reduction and stabilization of FeNPs were confirmed by FT-IR analysis. The biogenic FeNPs were tested for their size dependent antibacterial activity. The biogenic FeNPs prepared in 40mL extract concentrations exhibited strongest antibacterial activity against Pseudomonas aeruginosa i.e. 22 (±0.5) mm than FeNPs with 20mL and 60mL extract concentrations i.e. 18 (±0.4) mm and 14 (±0.3) mm respectively. The optimized FeNPs with 40mL peel extract are not only highly active for ROS generation but also show no hemolytic activity. Thus, FeNPs synthesized using the greener approach are found to have high antibacterial activity along with biocompatibility. This high antibacterial activity can be referred to small size and large surface area. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Antibacterial activity of Brazilian Amazon plant extracts

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    Ivana Barbosa Suffredini

    Full Text Available Infections caused by multiresistant bacteria are a widespread problem, especially in intensive care units. New antibiotics are necessary, and we need to search for alternatives, including natural products. Brazil is one of the hottest spots in the world in terms of biodiversity, but little is known about the chemical and pharmacological properties of most of the plants found in the Amazon rain forest and the Atlantic Forest. We screened 1,220 organic and aqueous extracts, obtained from Amazon and Atlantic rain forest plants, against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and E. coli. Seventeen organic and aqueous extracts obtained from 16 plants showed activity against both Gram-positive bacteria. None of the extracts showed relevant activity against the Gram-negative E. coli and Pseudomonas aeruginosa.

  4. A Structure-Activity Study of Antibacterial Diterpenoids

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    Loretta Vásquez

    2008-04-01

    Full Text Available An analysis of the antibacterial activities of 15 terpenoids, eleven of which werepreviously described by us and four were extracted from the literature, suggested twostructural requirements for activity of these and related compounds: a hydrophobic moiety,consisting of a substituted decalin skeleton, and a hydrophilic region possessing onehydrogen-bond-donor group. These structural requirements are responsible for an optimalinsertion of these and related compounds into cell membranes, as suggested by the resultsof docking some of these compounds into a model phospholipid bilayer.

  5. Antibacterial activity of some folklore medicinal plants from South India.

    Science.gov (United States)

    Goud, M Jaya Prakash; Komraiah, A; Rao, K Narasimha; Ragan, A; Raju, V S; Charya, M A Singara

    2008-06-18

    Antibacterial activity and phytochemical tests of eight whole plant methanol extracts belonging to family Euphorbiaceae were evaluated. In agar well diffusion assay the diameter of inhibition zones ranged from 3-13 mm. Phyllanthus emblica showed maximum activity of 13 mm. The MIC and MBC observed were 30-140 mcg/ml and 40-160 mcg/ml, respectively. P. piscatorum and P. emblica showed the lowest MIC (30 mcg/ml), P. emblica the lowest MBC (40 mcg/ml) and thus an effective inhibitor of the tested bacteria. Alkaloids, saponins and tannins were detected in 7 out of 8 tested plants.

  6. Antibacterial Activity of Aluminum in Clay from the Colombian Amazon.

    Science.gov (United States)

    Londono, S Carolina; Hartnett, Hilairy E; Williams, Lynda B

    2017-02-21

    The problems of antibiotic overuse compel us to seek alternative antibacterial agents. Some clays have been shown to kill antibiotic-resistant human pathogens and may provide an alternative to known antibiotics. Here we show that Al toxicity plays a central role in the antibacterial action of a kaolin-rich clay from the Colombian Amazon (AMZ). Antibacterial susceptibility testing shows minimum inhibitory concentrations of 80 mg/mL against a model Escherichia coli (ATCC 25922). The clay buffered the media pH to ∼4.6 and Eh values to +360 mV. Chemical analysis of AMZ and bacteria showed that Al, P, and transition metals (Fe, Cu, Mn, and Zn) were exchanged during incubation at 37 °C. Only Al derived from the clay exceeded the minimum inhibitory concentrations for E. coli under acidic conditions. Ion imaging showed elevated Al levels in the bacterial membrane, and high intracellular Fe levels, relative to those of untreated controls. Phosphorus depletion in E. coli after reaction with AMZ, together with evidence of membrane permeabilization, suggests that Al reacts with membrane phospholipids, enhancing intracellular transport of metals. These results highlight the importance of dissolved Al for amplifying the toxicity of transition metals to human pathogens.

  7. Study on the sorption process of triclosan on cationic microfibrillated cellulose and its antibacterial activity.

    Science.gov (United States)

    Zhang, Hongjie; Zeng, Xu; Xie, Jinglei; Li, Zhiqiang; Li, Hailong

    2016-01-20

    Cationic microfibrillated cellulose (CMFC), as one kind of cellulose-based materials, is widely used in many fields. In this work, it was functionalized with a traditional antibacterial agent (triclosan, TCS). The sorption process of TCS onto CMFC was expressed by kinetic and isotherm models. The results showed that there was a high correlation coefficient (R(2)>0.9) in the pseudo-second-order model and the isotherm models, indicating that CMFC had a good sorption capacity for TCS. The sorption type was chemisorption, and the reaction power was electrostatic interactions. The antibacterial activity of the assembled TCS/CMFC compound was tested by disk diffusion method, and it was found a higher antibacterial activity than CMFC alone (bigger inhibition zone diameters). Further, the functionalized TCS/CMFC compound was used in the fiber network during handsheets making, and it had a higher antibacterial rate than TCS alone (increase by 45.1% against Escherichia coli and by 54.8% against Staphylococcus aureus, respectively).

  8. Antibacterial and Antioxidant Activities of Acid and Bile Resistant Strains of Lactobacillus fermentum Isolated from Miang

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    Srikanjana Klayraung

    2009-12-01

    Full Text Available Miang is a kind of traditional fermented tea leaves, widely consumed in northern Thailand as a snack. It contains several kinds of Lactobacilli spp. The aim of this study was to isolate strains of Lactobacillus fermentum from miang and to investigate their antibacterial and antioxidant activities. The agar spot and well assays were used for determination of antibacterial power. The antibacterial mechanism was investigated by cell morphologic change under scanning electron microscope (SEM. Antioxidant activity was studied by means of free radical scavenging and ferric reducing power assays. The acid and bile screening tests indicated that L. fermentum FTL2311 and L. fermentum FTL10BR presented antibacterial activity against several pathogenic bacteria: Listeria monocytogenes DMST 17303, Salmonella Typhi DMST 5784, Shigella sonnei DMST 561 (ATCC 11060and Staphylococcus aureus subsp. aureus DMST 6512 (ATCC 6538Ptm. The results from SEM suggested that the antibacterial action was due to the destruction of cell membrane which consequently caused the pathogenic cell shrinking or cracking. The antioxidant study suggested that both L. fermentum FTL2311 and L. fermentum FTL10BR strains could liberate certain substances that possessed antioxidant activity expressed as trolox equivalent antioxidant capacity (TEAC and equivalent concentration (EC values for free radical scavenging and reducing mechanisms, respectively. The supernatant of L. fermentum FTL2311 broth revealed TEAC and EC values of 22.54±0.12 and 20.63±0.17 µM.mg-1 respectively, whereas that of L. fermentum FTL10BR yielded TEAC and EC values of 24.09±0.12 and 21.26±0.17 µM.mg-1 respectively. These two strains isolated from miang present high potential as promising health-promoting probiotics.

  9. Antibacterial and biofilm inhibitory activities of bacteria associated with polychaetes

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    Chellamnadar Vaikundavasagom Sunjaiy Shankar

    2015-06-01

    Full Text Available Objective: To study the antibacterial and antibiofilm activities expressed by epibiotic bacteria associated with the polychaetes Platynereis dumerilii and Syllis sp. Methods: A total of 32 cultivable bacterial strains were isolated from the two polychaete species. The crude extracts were tested for antibacterial activity and biofilm inhibitory activity against pathogenic and biofilm-forming bacterial strains. Extracts of the strains which showed strong activity were analyzed by thin-layer chromatography (TLC and the bacterial strains were identified based on 16S rRNA gene sequencing. Results: Extracts of 13 bacterial strains showed inhibitory activity against pathogenic and biofilm-forming bacteria. The crude extracts also affected the synthesis of extracellular polymeric substances and cell surface hydrophobicity of the Alteromonas sp. isolated from marine biofilm. The adhesion of Alteromonas sp. on glass surface showed significant variation between surface-associated bacterial crude extract treatment and control groups. Among the 13 bacteria, two strains PA8 and PA19 were further analyzed for bioactive fractions. Thinlayer chromatography indicated the presence of a single active fraction in the crude extract of both the bacterial strains. The epibiotic bacterial strains P8 and P19 were identified as Exiguobacterium sp. and Actinobacterium sp. respectively based on 16S rRNA gene sequencing. Conclusions: The present study indicates that bacteria associated with marine invertebrates inhabiting the coastal waters could be used as a potential source for the isolation of bioactive metabolites.

  10. Antibacterial and bioiflm inhibitory activities of bacteria associated with polychaetes

    Institute of Scientific and Technical Information of China (English)

    Sathianeson Satheesh; Nadarajan Viju

    2015-01-01

    Objective:To study the antibacterial and antibiofilm activities expressed by epibiotic bacteria associated with the polychaetes Platynereis dumerilii and Syllis sp. Methods:A total of 32 cultivable bacterial strains were isolated from the two polychaete species. The crude extracts were tested for antibacterial activity and biofilm inhibitory activity against pathogenic and biofilm-forming bacterial strains. Extracts of the strains which showed strong activity were analyzed by thin-layer chromatography (TLC) and the bacterial strains were identified based on 16S rRNA gene sequencing. Results:Extracts of 13 bacterial strains showed inhibitory activity against pathogenic and biofilm-forming bacteria. The crude extracts also affected the synthesis of extracellular polymeric substances and cell surface hydrophobicity of the Alteromonas sp. isolated from marine biofilm. The adhesion of Alteromonas sp. on glass surface showed significant variation between surface-associated bacterial crude extract treatment and control groups. Among the 13 bacteria, two strains PA8 and PA19 were further analyzed for bioactive fractions. Thin-layer chromatography indicated the presence of a single active fraction in the crude extract of both the bacterial strains. The epibiotic bacterial strains P8 and P19 were identified as Exiguobacterium sp. and Actinobacterium sp. respectively based on 16S rRNA gene sequencing. Conclusions:The present study indicates that bacteria associated with marine invertebrates inhabiting the coastal waters could be used as a potential source for the isolation of bioactive metabolites.

  11. Antioxidant, antimutagenic and antibacterial activities of extracts from Phyllanthus emblica branches

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    Bungorn Sripanidkulchai

    2014-12-01

    Full Text Available Phyllanthus emblica is an euphorbiaceous plant that has long been used as an ingredient in traditional medicines and functional foods. Although traditional remedies use several parts including the fruit, leaf, flower, stem and roots, the fruit is the most popular. It has been used for health promotion, anti-aging and also for treatment of wide ranges of symptoms and diseases. Because of the broad spectrum of pharmacological activities and high demand for the P. emblica fruit, there is a shortage of raw materials. Furthermore, there is a seasonal limitation in which the fruit comes out once a year. The aim of this study is to investigate the bioactive potential and the possibility to use the plant branch. Alcohol based extracts of P.emblica branch were analyzed for total phenolic content, antioxidant, antibacterial and antimutagenic activities. P. emblica branches were used to prepare the 50% ethanolic extract by maceration (EBE and methanolic extract by Soxhlet apparatus (MBE. Total phenolic content was determined by Folin-Ciocalteu method and DPPH was used to analyze the antioxidative activity. Antibacterial activity was evaluated by microdilution method and expressed by minimal inhibitory concentration (MIC and minimal bactericidal concentration (MBC. Antimutagenicity was performed by preincubation bacterial assay in Salmonella typhimurium TA98 and TA100 strains. It was found that both EBE and MBE contained high total phenolic content (643 and 547 TAE mg/g and strong antioxidative activity (EC50 at 30 and 23 mg/ml. The extracts showed antimutagenicity to both direct and indirect-acting mutagens in TA98 and TA100 strains. Both extracts possess antibacterial activity against Staphylococcus aureus, S. epidermidis, Escherichia coli, Salmonella sp. and Pseudomonas aeruginosa. In conclusion, the alcoholic extracts of P. emblica branch possess high phenolic content with strong antioxidative, antimutagenic and antibacterial activities as previously

  12. Determination of reactive oxygen generated from natural medicines and their antibacterial activity

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    Noriko Tajima

    2016-08-01

    Galla chinensis generated 2.4×10−4 mol/L hydrogen peroxide from a 1 mg/mL solution. In bacterial growth tests, Galla chinensis extract had antibacterial activity against Escherichia coli, Staphylococcus aureus, Bacteroides thetaiotaomicron, Campylobacter sputorum biovar sputorum, Streptococcus salivarius thermophilus, Lactobacillus casei, and Bifidobacterium longum infantis. This antibacterial activity was decreased by the addition of catalase. It revealed that hydrogen peroxide which Galla chinensis produced participated in antibacterial activity.

  13. Synthesis, Characterization and Antibacterial Activity of New Ln( Ⅲ) Complexes with an Unsymmetrical Schiff Base Ligand

    Institute of Scientific and Technical Information of China (English)

    BI Caifeng; YAN Liangliang; FAN Yuhua; ZHANG Xia; WANG Aidong

    2006-01-01

    A new unsymmetrical Schiff base ligand (H2LLi) was synthesized using L-lysine, salicylaldehyde and 2-hydroxyprepared and characterized by elemental analyses, IR spectra, UV spectra, TG-DTG and molar conductance.The antibacterial activities of the ligand and its complexes are also studied.The antibacterial experiments indicate that the ligand and its complexes possess antibacterial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis and that the complexes have higher activity than those of the ligand.

  14. Synthesis and antibacterial activity studies of 6-methoxyquinazoline-triazole hybrid derivatives

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    Venkataramireddy Veeramreddy

    2015-12-01

    Full Text Available The Click reaction between the electronically divergent triazole compounds 4-((l-(4-(tert-butylbenzyl-1H-l,2,3-triazol-4-ylmethoxy-5-methoxy-2-nitrobenzamides (8a-e with different aldehydes using Na 2S 2O 4 in DMSO was performed to obtain hybrid of quinazolinone-triazole derivatives (10a-o. All the synthesized compounds were fully characterized on the basis of their detailed spectral studies and screened for their antibacterial activities strains using paper disc method. The compounds (10 a-o were evaluated for their antibacterial activity against human pathogenic organism Escherichia Coli, Staphylococcus aureus (Table 1. The investigation of antibacterial screening data reveal that 10e, 10f, 10g, 10j and 10n were highly active against E. coli, where as 10b, 10d, 10j,10k and 10o showed least activity. Compounds 10b, 10e, 10f, 10g, 10i, 10k and 10n showed high activity against S. aureus, where as compounds 10d, 10j, 10o showed least activity. Compounds 10c, 10h, 10l and 10o were inactive against both organisms employed.

  15. Influence of Composite Phosphate Inorganic Antibacterial Materials Containing Rare Earth on Activated Water Property of Ceramics

    Institute of Scientific and Technical Information of China (English)

    梁金生; 梁广川; 祁洪飞; 吴子钊; 冀志江; 金宗哲

    2004-01-01

    Antibacterial ceramic was prepared by doping enamel slurry with composite phosphate inorganic antibacterial materials containing rare earth (inorganic antibacterial additives), and then the mechanisms for activating water and improving seed germinative property were tested by nuclear magnetic resonance (NMR) and the method of testing oxygen dissolved in activated water. Results show that the half peak width of 17O-NMR for tap water activated by the antibacterial ceramic drops from 115.36 to 99.15 Hz, and oxygen concentrations of activated water increase by 20%, germinate rate of horsebean and earthnut seeds increases by 12.5% and 7.5%, respectively. Therefore antibacterial ceramic doped enamel slurry with inorganic antibacterial additives containing rare earth can reduce the volume of clusters of water molecules, improve activation of tap water, and promote plant seeds germinate.

  16. Antibacterial activities effectuated by co-continuous epoxy-based polymer materials.

    Science.gov (United States)

    Kubo, Takuya; Yasuda, Koji; Tominaga, Yuichi; Otsuka, Koji; Hosoya, Ken

    2013-07-01

    We report antibacterial activities of the epoxy-resin-based monolithic media (epoxy monoliths) having macroporous co-continuous structure as well as hydrophobic and/or hydrophilic surface. Utilizing epoxy monoliths containing ammonium groups, the antibacterial experiments were examined using Escherichia coli. As the results, the monolithic media prepared with an epoxy monomer having nitrogen atoms clearly showed antibacterial activities, while those prepared using the monomer without nitrogen atom showed less antibacterial activities. Additionally, the quaternization of the epoxy polymers were expressed significant antibacterial activities. Further studies elucidated that the observed antibacterial activities involved the steep effect based on pH changing of solution and hydrophobic interactions by the quaternary ammonium. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. In vitro antibacterial activity of Sri Lankan orthodox black tea (Camellia sinensis L. belonging to different agro-climatic elevations

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    Wanigasekara Daya Ratnasooriya

    2016-08-01

    Full Text Available Objective: To investigate the antibacterial properties of three grades of orthodox Sri Lankan black tea belonging to the three agro-climatic elevations. Methods: Methanloic extracts of orange pekoe (OP, broken orange pekoe fannings (BOPF and Dust No. 1 belonging to three agro-climatic elevations (low, mid and high grown were made and tested in vitro (concentration: 300 µg/disc against Gram-positive pathogenic bacteria, Staphylococcus aureus (ATCC 25923 (S. aureus and Bacillus cereus (ATCC 11778 (B. cereus, and two Gram-negative bacteria Pseudomonas aeruginosa (ATCC 9027 (P. aeruginosa and Escherichia coli (ATCC 35218 (E. coli, using agar disc diffusion assay. Gentamycin (10 µg/disc was used as the positive control and methanol as the negative control. Minimum inhibitory concentration (MIC values were evaluated, using micro dilution method. Results: None of the tea extracts exerted an antibacterial action against P. aeruginosa and E. coli. In contrast mild to moderate antibacterial activity was exerted against S. aureus and B. cereus. Further gentamycin exhibited strong antibacterial activity against all the four bacterial species. Further low MIC values were evident for tea samples against the two Gram-positive bacteria. The order of anti-bacterial activity for tea extracts was Dust No. 1 > BOPF > OP. Conclusions: It is concluded that Sri Lankan orthodox black tea belonging to Dust No. 1, BOPF, and OP pocess in vitro antibacterial activity against S. aureus and B. cereus but not against Gram-positive bacteria P. aeruginosa and E. coli.

  18. Antibacterial activity of actinomycetes isolated from different soil samples of Sheopur (A city of central India

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    Hotam S Chaudhary

    2013-01-01

    Full Text Available The main objective of the present study was isolation, purification, and characterization of actinomycetes from soil samples, having antimicrobial activity against 12 selected pathogenic strains. Soils samples were taken from different niche habitats of Sheopur district, Madhya Pradesh, India. These samples were serially diluted and plated on actinomycete isolation agar media. Potential colonies were screened, purified, and stored in glycerol stock. Isolates were morphologically and biochemically characterized. These isolates were subjected to extraction for production of the antibacterial compound. Antibacterial activity and Minimum Inhibitory Concentration (MIC of the purified extract of isolates were evaluated. Totally 31 actinomycete isolates were tested for antagonistic activity against 12 pathogenic microorganisms. Isolates AS14, AS27, and AS28 were highly active, while AS1 showed less activity against the pathogenic microorganisms. Isolate AS7 exhibited the highest antagonistic activity against Bacillus cereus (24 mm and AS16 showed the highest activity against Enterococcus faecalis (21 mm. MIC was also determined for actinomycete isolates against all the tested microorganisms. MIC of actinomycete isolates was found to be 2.5 mg/ml against Shigella dysenteriae, Vancomycin-resistant enterococci, and Klebsiella pneumoniae, and was 1.25 mg/ml for Staphylococcus saprophyticus, Streptococcus pyogenes, Staphylococcus epidermidis, Methicillin-resistant Staphylococcus, Bacillus cereus, Staphylococcus xylosus, Methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, and Staphylococcus aureus. All actinomycetes isolates showed antibacterial activity against S. aureus, while they showed less activity against S. dysenteriae. These isolates had antibacterial activity and could be used in the development of new antibiotics for pharmaceutical or agricultural purposes.

  19. ASSESSMENT OF ANTIOXIDANT, CYTOTOXIC AND ANTIBACTERIAL ACTIVITIES OF DIFFERENT FRACTIONS OF CRUDE EXTRACT OF STEPHANIA JAPONICA STEM

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    Bishwajit Bokshi , S.M. Abdur Rahman*, S. K. Sadhu , Ashif Muhammad and Hemayet Hossain

    2013-04-01

    Full Text Available ABSTRACT: The different fractions of crude methanolic extract of stem of Stephania japonica (Thunb. Miers was evaluated for antioxidant, cytotoxic and antibacterial activities. The various fractions of S. japonica Stem i.e. Ethyl Acetate (EAJS, CHCl3 (CFJS, CCl4 (CTJS and Petroleum ether (PEJS were subjected to free radical scavenging activity. In this investigation, CFJS showed the most significant free radical scavenging activity with IC50 value of 119.0µg/ml for S. japonica stem. Cytotoxic activity was investigated by brine shrimp (Artemia salina lethality assay. The LC50 value of sample CTJS (Carbon Tetrachloride fraction of S. japonica Stem, was 3.0µg/ml is highly most significant. Antibacterial activity was tested by disk diffusion method. The Carbon Tetrachloride soluble fraction showed good antibacterial activity against different species of bacteria at different doses. The Ethyl Acetate soluble fraction shows good activity only against E. coli at different doses.

  20. Antibacterial activity of some selected medicinal plants of Pakistan

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    Chaudhary Fayyaz M

    2011-06-01

    Full Text Available Abstract Background Screening of the ethnobotenical plants is a pre-requisite to evaluate their therapeutic potential and it can lead to the isolation of new bioactive compounds. Methods The crude extracts and fractions of six medicinal important plants (Arisaema flavum, Debregeasia salicifolia, Carissa opaca, Pistacia integerrima, Aesculus indica, and Toona ciliata were tested against three Gram positive and two Gram negative ATCC bacterial species using the agar well diffusion method. Results The crude extract of P. integerrima and A. indica were active against all tested bacterial strains (12-23 mm zone of inhibition. Other four plant's crude extracts (Arisaema flavum, Debregeasia salicifolia, Carissa opaca, and Toona ciliata were active against different bacterial strains. The crude extracts showed varying level of bactericidal activity. The aqueous fractions of A. indica and P. integerrima crude extract showed maximum activity (19.66 and 16 mm, respectively against B. subtilis, while the chloroform fractions of T. ciliata and D. salicifolia presented good antibacterial activities (13-17 mm zone of inhibition against all the bacterial cultures tested. Conclusion The methanol fraction of Pistacia integerrima, chloroform fractions of Debregeasia salicifolia &Toona ciliata and aqueous fraction of Aesculus indica are suitable candidates for the development of novel antibacterial compounds.

  1. Antibacterial activity of different honeys against pathogenic bacteria.

    Science.gov (United States)

    Voidarou, C; Alexopoulos, A; Plessas, S; Karapanou, A; Mantzourani, I; Stavropoulou, E; Fotou, K; Tzora, A; Skoufos, I; Bezirtzoglou, E

    2011-12-01

    To study the antimicrobial activity of honey, 60 samples of various botanical origin were evaluated for their antimicrobial activities against 16 clinical pathogens and their respective reference strains. The microbiological quality of honeys and the antibiotic susceptibility of the various isolates were also examined. The bioassay applied for determining the antimicrobial effect employs the well-agar diffusion method and the estimation of minimum active dilution which produces a 1mm diameter inhibition zone. All honey samples, despite their origin (coniferous, citrus, thyme or polyfloral), showed antibacterial activity against the pathogenic and their respective reference strains at variable levels. Coniferous and thyme honeys showed the highest activity with an average minimum dilution of 17.4 and 19.2% (w/v) followed by citrus and polyfloral honeys with 20.8 and 23.8% respectively. Clinical isolates of Staphylococcus aureus subsp. aureus, Escherichia coli, Salmonella enterica subsp. Enterica, Streptococcus pyogenes, Bacillus cereus and Bacillus subtilis were proven to be up to 60% more resistant than their equal reference strains thus emphasizing the variability in the antibacterial effect of honey and the need for further research. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Antibacterial, antioxidant and tyrosinase-inhibition activities of pomegranate fruit peel methanolic extract

    National Research Council Canada - National Science Library

    Fawole, Olaniyi A; Makunga, Nokwanda P; Opara, Umezuruike Linus

    2012-01-01

    This study evaluated, using in vitro assays, the antibacterial, antioxidant, and tyrosinase-inhibition activities of methanolic extracts from peels of seven commercially grown pomegranate cultivars...

  3. Analysis and antibacterial activity of Nigella sativa essential oil formulated in microemulsion system.

    Science.gov (United States)

    Shaaban, Hamdy A; Sadek, Zainab; Edris, Amr E; Saad-Hussein, Amal

    2015-01-01

    The Essential oil (EO) of Nigella sativa (black cumin) was extracted from the crude oil and the volatile constituents were characterized using gas chromatographic analysis. The EO was formulated in water-based microemulsion system and its antibacterial activity against six pathogenic bacteria was evaluated using the agar well diffusion method. This activity was compared with two other well known biologically active natural and synthetic antimicrobials namely eugenol and Ceftriaxone(®). Results showed that N. sativa EO microemulsion was highly effective against S. aureus, B. cereus and S. typhimurium even at the lowest tested concentration of that EO in the microemulsion (100.0 μg/well). Interestingly, the EO microemulsion showed higher antibacterial activity than Ceftriaxone solution against S. typhimurium at 400.0 μg/well and almost comparable activity against E. coli at 500.0 μg/well. No activity was detected for the EO microemulsion against L. monocytogenes and P. aeruginosa. Eugenol which was also formulated in microemulsion was less effective than N. sativa EO microemulsion except against P. aeruginosa. The synthetic antibiotic (Ceftriaxone) was effective against most of the six tested bacterial strains. This work is the first report revealing the formulation of N. sativa EO in microemulsion system and investigating its antibacterial activity. The results may offer potential application of that water-based microemulsion in controlling the prevalence of some pathogenic bacteria.

  4. Superior Antibacterial Activity of Fe3O4-TiO2 Nanosheets under Solar Light.

    Science.gov (United States)

    Ma, Shuanglong; Zhan, Sihui; Jia, Yanan; Zhou, Qixing

    2015-10-07

    Fe3O4-TiO2 nanosheets (Fe3O4-TNS) were synthesized by means of lamellar reverse micelles and solvothermal method, which were characterized by TEM, XRD, XPS, BET, and magnetic property analysis. It can be found that Fe3O4-TNS nanosheets exhibited better photocatalytic antibacterial activity toward Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus than pure Fe3O4 and TNS, and the antibacterial efficiency could reach 87.2% and 93.7% toward E. coli and S. aureus with 100 μg/mL Fe3O4-TNS after 2 h of simulated solar light illumination, respectively. The photocatalytic destruction of bacteria was further confirmed by fluorescent-based cell live/dead test and SEM images. It was uncovered that Fe3O4-TNS inactivated G- E. coli and G+ S. aureus by different mechanisms: the destruction of outer membranes and ruptured cell bodies were responsible for the bactericidal effect against E. coli, while the antibacterial effect toward S. aureus were due to the fact that the cells were adsorbed in form of clusters by massive Fe3O4-TNS, which could restrict their activities and cause malfunction of the selective permeable barriers. Furthermore, the antibacterial mechanism was studied by employing scavengers to understand exact roles of different reactive species, indicating the key roles of h(+) and H2O2. The recovery and reusability experiments indicated that Fe3O4-TNS still retained more than 90% bacteria removal efficiency even after five cycles. Considering the easy magnetic separation, bulk availability, and high antibacterial activity of Fe3O4-TNS, it is a promising candidate for cleaning the microbial contaminated water environment.

  5. In vitro propagation and antibacterial activity of Clitoria ternatea Linn.

    Institute of Scientific and Technical Information of China (English)

    Arumugam M; Panneerselvam R

    2012-01-01

    Objective: To compare the antibacterial property between tissue cultured and wild plants ofClitoria ternatea. Methods: Callus formation, shoot multiplication and rooting were carried out in MS medium supplemented with 2,4-D and KN; BA, KN and IAA; NAA and NAA, respectively. The antibacterial activity was evaluated using disc diffusion method against the gram positive bacteria Bacillus cereus, Bacillus subtilis and Staphylococcus aureus, the gram negative Klebsiellapneumonia, Proteus vugaris and Salmonella typhi. Soxhlet apparatus was used for extraction with a series of solvents methonolic, perolium ether and ethyl acetate. Results: The best shoot initiation was resulted in KN (1.0 mg/L) and IAA (0.5 mg/L).The maximum shoot multiplication was obtained by BA (0.75 mg/L) and IAA (0.5 mg/L). The maximum callus initiation was observed by adding 2,4-D (1.0 mg/L) and KN (0.5 mg/L) using leaf explants. Callus differentiation was achieved by addition of 2, 4-D (0.3 mg/L) and KN (0.3 mg/L). The combination of plant growth regulators such as 2,4-D and KN induced best callus in all the explants of Clitoria ternatea compared to other hormonal combination. Maximum rooting was achieved by adding NAA (1.0 mg/L) on half strength MS medium. The methonolic extract of callus showed higher activity in Klebsiella pneumonia and Staphylococcus aureus than rest of the organisms. Conclusions: From the present investigation, it can be concluded that in vitro derived callus and plants of Clitoria ternatea exhibits antibacterial activity against certain pathogenic bacteria.

  6. Antibacterial and antibiotic potentiating activities of tropical marine sponge extracts.

    Science.gov (United States)

    Beesoo, Rima; Bhagooli, Ranjeet; Neergheen-Bhujun, Vidushi S; Li, Wen-Wu; Kagansky, Alexander; Bahorun, Theeshan

    2017-06-01

    Increasing prevalence of antibiotic resistance has led research to focus on discovering new antimicrobial agents derived from the marine biome. Although ample studies have investigated sponges for their bioactive metabolites with promising prospects in drug discovery, the potentiating effects of sponge extracts on antibiotics still remains to be expounded. The present study aimed to investigate the antibacterial capacity of seven tropical sponges collected from Mauritian waters and their modulatory effect in association with three conventional antibiotics namely chloramphenicol, ampicillin and tetracycline. Disc diffusion assay was used to determine the inhibition zone diameter (IZD) of the sponge total crude extracts (CE), hexane (HF), ethyl acetate (EAF) and aqueous (AF) fractions against nine standard bacterial isolates whereas broth microdilution method was used to determine their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs) and antibiotic potentiating activity of the most active sponge extract. MIC values of the sponge extracts ranged from 0.039 to 1.25mg/mL. Extracts from Neopetrosia exigua rich in beta-sitosterol and cholesterol displayed the widest activity spectrum against the 9 tested bacterial isolates whilst the best antibacterial profile was observed by its EAF particularly against Staphylococcus aureus and Bacillus cereus with MIC and MBC values of 0.039mg/mL and 0.078mg/mL, respectively. The greatest antibiotic potentiating effect was obtained with the EAF of N. exigua (MIC/2) and ampicillin combination against S. aureus. These findings suggest that the antibacterial properties of the tested marine sponge extracts may provide an alternative and complementary strategy to manage bacterial infections. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Preparation and antibacterial activity of titanium nanotubes loaded with Ag nanoparticles in the dark and under the UV light

    Science.gov (United States)

    Zhao, Chanjuan; Feng, Bo; Li, Yiting; Tan, Jing; Lu, Xiong; Weng, Jie

    2013-09-01

    Highly ordered anatase-type titanium nanotubes (TNTs) arrays were prepared on the surface of titanium by anodization and subsequently heat treatment at 450 °C for 5 h. Three different diameters of TNTs (50 nm, 75 nm, 100 nm) were fabricated via the voltage changed. Then Ag was loaded on these TNTs through a photo-reduction method of AgNO3 solution. Ag particles with the size of approximately 10 nm were uniformly distributed on the surface of TNTs. Samples were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, atomic absorption spectrometry and contact angle test. Meanwhile, the antibacterial activities of Ag-loaded TiO2 nanotubes (TNTs-Ag) were evaluated through antibacterial experiment against both Escherichia coli and Staphylococcus aureus in the dark and under the UV light (λ = 365 nm) irradiation respectively. The results indicated that under the UV light TNTs-Ag had higher antibacterial activities to the two bacteria than TNTs, though the later also showed antibacterial ability. While in the dark environment, the loading of Ag nanoparticles largely enhanced the antibacterial activities of the titanium nanotubes. In addition, the antibacterial efficiencies of all samples increased with increase of nanotube diameters both in the dark and under the UV light. Therefore, TNTs loaded with Ag nanoparticles are expected to be well suited for endo-prosthetic applications due to their excellent antibacterial activities in the dark. And their antibacterial efficiencies can be controlled by adjusting diameters of TNTs, distribution and size of Ag nanoparticles.

  8. Preparation and antibacterial activity of titanium nanotubes loaded with Ag nanoparticles in the dark and under the UV light

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chanjuan; Feng, Bo, E-mail: fengbo@swjtu.edu.cn; Li, Yiting; Tan, Jing; Lu, Xiong; Weng, Jie

    2013-09-01

    Highly ordered anatase-type titanium nanotubes (TNTs) arrays were prepared on the surface of titanium by anodization and subsequently heat treatment at 450 °C for 5 h. Three different diameters of TNTs (50 nm, 75 nm, 100 nm) were fabricated via the voltage changed. Then Ag was loaded on these TNTs through a photo-reduction method of AgNO{sub 3} solution. Ag particles with the size of approximately 10 nm were uniformly distributed on the surface of TNTs. Samples were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, atomic absorption spectrometry and contact angle test. Meanwhile, the antibacterial activities of Ag-loaded TiO{sub 2} nanotubes (TNTs-Ag) were evaluated through antibacterial experiment against both Escherichia coli and Staphylococcus aureus in the dark and under the UV light (λ = 365 nm) irradiation respectively. The results indicated that under the UV light TNTs-Ag had higher antibacterial activities to the two bacteria than TNTs, though the later also showed antibacterial ability. While in the dark environment, the loading of Ag nanoparticles largely enhanced the antibacterial activities of the titanium nanotubes. In addition, the antibacterial efficiencies of all samples increased with increase of nanotube diameters both in the dark and under the UV light. Therefore, TNTs loaded with Ag nanoparticles are expected to be well suited for endo-prosthetic applications due to their excellent antibacterial activities in the dark. And their antibacterial efficiencies can be controlled by adjusting diameters of TNTs, distribution and size of Ag nanoparticles.

  9. Chemical composition and antibacterial activity of Opuntia ficus-indica f. inermis (cactus pear) flowers.

    Science.gov (United States)

    Ennouri, Monia; Ammar, Imene; Khemakhem, Bassem; Attia, Hamadi

    2014-08-01

    Opuntia ficus-indica f. inermis (cactus pear) flowers have wide application in folk medicine. However, there are few reports focusing on their biological activity and were no reports on their chemical composition. The nutrient composition and hexane extracts of Opuntia flowers at 4 flowering stages and their antibacterial and antifungal activities were investigated. The chemical composition showed considerable amounts of fiber, protein, and minerals. Potassium (K) was the predominant mineral followed by calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), and zinc (Zn). The main compounds in the various hexane extracts were 9.12-octadecadienoic acid (29-44%) and hexadecanoic acid (8.6-32%). The antibacterial activity tests showed that O. inermis hexane extracts have high effectiveness against Escherichia coli and Staphylococcus aureus, making this botanical source a potential contender as a food preservative or food control additive.

  10. Antibacterial and antioxidant activities of Mentha piperita L.

    Directory of Open Access Journals (Sweden)

    Rajinder Singh

    2015-05-01

    Full Text Available The antibacterial activity of peppermint oil and different extracts of Mentha piperita against some Gram-positive and Gram-negative bacterial strains was evaluated in the present research work by agar well diffusion method. It was found that the distilled concentrations of essential oil inhibited the growth of microorganisms and the results were comparable with those of antibiotic gentamycin. Essential oils showed a wider spectrum of activity but less strong inhibition as compared to the investigated commercial antibiotic. Minimum inhibitory concentrations (MICs for the bacterial species ranged from 0.4% to 0.7% v/v. The oil and extracts also exhibited significant antioxidant activity and the oil showed about half potency when compared to the standard BHT. These results indicated the strong antibacterial and antioxidant activities of peppermint oil but additional investigations need to be performed in order to confirm the safety of these concentrations (MIC for human consumption. Peppermint oil could be used as a good conservation agent by inhibiting some food borne pathogens.

  11. PHYTOCHEMICAL SCREENING AND ANTIBACTERIAL ACTIVITY OF STACHYTARPHETA INDICA

    Directory of Open Access Journals (Sweden)

    H.N. Krishna Kumar*, S.D.Preethi, E. Chandana and Jyoti Bala Chauhan

    2012-01-01

    Full Text Available Phytochemical screening and antibacterial activity of aqueous and methanolic root extracts of Stachytarpheta indica Vahl. was assessed. Phytochemical analysis revealed the presence of flavonoids, terpenoides, tannins and reducing sugars. The antibacterial properties of both the aqueous and methanolic extracts were studied against clinically important bacteria viz., Escherichia coli, Bacillus cereus, Pseudomonas aeruginosa and Enterobacter aerogens by disc diffusion method. The aqueous extract showed significant activity against all the presently investigated species of bacteria which is comparable with standard antibiotic streptomycin. At the concentrations of 50-100µg /disc, aqueous extract showed significant zone of inhibition against E. coli, (14 mm, B. cereus (13 mm, P. aeruginosa, (17 mm, and E. aerogens (7 mm. Minimum Inhibitory Concentration (MIC and Minimum Bactericidal Concentration (MBC have been determined. The MIC values observed was 20, 30, 5 and 25µg/ml (for aqueous extract and 40, 35, 20 and 30µg/ml (for methanolic extract against E. coli, B. cereus, P. aeruginosa, and E. aerogens respectively. Further isolation of active compound responsible for the activity could be the potential sources of new antimicrobial agents.

  12. A biotemplated nickel nanostructure: Synthesis, characterization and antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Ashtari, Khadijeh [Department of Nanobiotechnology, Faculty of Biological Science, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Fasihi, Javad [Department of Analytical Chemistry, Faculty of Science, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mollania, Nasrin [Department of Biochemistry, Faculty of Biological Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran (Iran, Islamic Republic of); Khajeh, Khosro, E-mail: khajeh@modares.ac.ir [Department of Nanobiotechnology, Faculty of Biological Science, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Department of Biochemistry, Faculty of Biological Science, Tarbiat Modares University, P.O. Box 14115-175, Tehran (Iran, Islamic Republic of)

    2014-02-01

    Highlights: • Nickel nanostructure-encapsulated bacteria were prepared using electroless deposition. • Bacterium surface was activated by red-ox reaction of its surface amino acids. • Interfacial changes at cell surfaces were investigated using fluorescence spectroscopy. • TEM and AFM depicted morphological changes. • Antibacterial activity of nanostructure was examined against different bacteria strains. - Abstract: Nickel nanostructure-encapsulated bacteria were prepared using the electroless deposition procedure and activation of bacterium cell surface by red-ox reaction of surface amino acids. The electroless deposition step occurred in the presence of Ni(II) and dimethyl amine boran (DMAB). Interfacial changes at bacteria cell surfaces during the coating process were investigated using fluorescence spectroscopy. Fluorescence of tryptophan residues was completely quenched after the deposition of nickel onto bacteria surfaces. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) depicted morphological changes on the surface of the bacterium. It was found that the Ni coated nanostructure was mechanically stable after ultrasonication for 20 min. Significant increase in surface roughness of bacteria was also observed after deposition of Ni clusters. The amount of coated Ni on the bacteria surface was calculated as 36% w/w. The antibacterial activity of fabricated nanostructure in culture media was examined against three different bacteria strains; Escherichia coli, Bacillus subtilis and Xantomonas campestris. The minimum inhibitory concentrations (MIC) were determined as 500 mg/L, 350 mg/L and 200 mg/L against bacteria, respectively.

  13. ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES OF SELECTED ARMENIAN MEDICINAL PLANTS

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    Vardapetyan H

    2014-07-01

    Full Text Available The antioxidant potentials of ethanolic and aqueous extracts of Hypericum perforatum, Ocimum basilicum, Laurus nobilis leaves were evaluated by 2, 2-diphenyl-l-picrylhydrazyl radical (DPPH assay. Simultaneously total flavonoids content and antibacterial potential of all the tested extract was also monitored. The highest radical scavenging capacity (RSC was reported in ethanolic extract of H. perforatum leaves while the lowest RSC was reported in the aqueous extract of L. nobilis. The ethanolic extracts of L. nobilis posses more DPPH radical scavenging action, than their aqueous extracts. Ethanolic and aqueous extracts of H. perforatum shows significant antioxidant activity, it is near to inhibition capacities while ethanolic extract of O. basilicum leaf has exhibited small activity as compared with its aqueous extract. RSC of ethanolic extracts can correlates with flavonoids content. The antiradical activity of ethanolic and aqueous extracts of L.nobilis leaf can also correlate with total flavonoids content, while such type of correlation was not reported in the case of H. perforatum and O. basilicum leaves extracts. RSC of tested extracts can be ranged in the following way: quercetin > rutin > eth. H. perforatum > aq. H. perforatum > aq. O. basilicum > eth L.nobilis > eth. O. basilicum > aq. L.nobilis. All the ethanolic extracts express more antibacterial activity than aqueous extracts.

  14. Screening for antibacterial and antibiofilm activities in Astragalus angulosus

    Science.gov (United States)

    Kanaan, Hussein; El-Mestrah, Majid; Sweidan, Alaa; As-Sadi, Falah; Bazzal, Ali Al; Chokr, Ali

    2017-01-01

    Aim: In a search for finding novel therapeutic agents, extracts from an endemic Lebanese plant, Astragalus angulosus, were evaluated for their potential in-vitro antibacterial and antibiofilm activities against three Gram-positive bacterial strains; Staphylococcus epidermidis (CIP444), Staphylococcus aureus (ATCC25923), and Enterococcus faecalis (ATCC29212); in addition to two Gram-negative strains, Escherichia coli (ATCC35218) and Pseudomonas aeruginosa (ATCC27853). Materials and Methods: The plant was collected in April of 2013 and divided into several different portions, then its extracts were obtained by maceration using two different solvents. Extract analysis followed directly where microtiter broth dilution method was employed to assess antibacterial activity, while antibiofilm potential was tested using colorimetric method. Results: Whole plant ethanolic extract showed the highest bacteriostatic effect at a concentration of 12.78 mg/ml and also was the most versatile exerting its effect against 3 different strains. Other extracts also exhibited an effect but at higher concentrations and each against a single strain. Regarding antibiofilm activity, the majority of the extracts were able to eradicate >50% of S. epidermidis preformed biofilm, where the highest activity was obtained with flower fraction extracted in water, achieving 67.7% biofilm eradication at 0.2 mg/ml. Conclusions: This plant possesses a promising potential in regard to eradicating bacteria and their biofilms and it is the first contributing step of establishing a library for the endemic Lebanese plants in this domain. PMID:28163960

  15. Rosmarinus officinalis essential oil: antiproliferative, antioxidant and antibacterial activities

    Directory of Open Access Journals (Sweden)

    Abdullah Ijaz Hussain

    2010-12-01

    Full Text Available The aim of this work was to investigate and compare the antiproliferative, antioxidant and antibacterial activities of Rosmarinus officinalis essential oil, native to Pakistan. The essential oil content from the leaves of R. officinalis was 0.93 g 100g-1. The GC and GC-MS analysis revealed that the major components determined in R. officinalis essential oil were 1,8-cineol (38.5%, camphor (17.1%, α-pinene (12.3%, limonene (6.23%, camphene (6.00% and linalool (5.70%. The antiproliferative activity was tested against two cancer (MCF-7 and LNCaP and one fibroblast cell line (NIH-3T3 using the MTT assay, while, the antioxidant activity was evaluated by the reduction of 2, 2-diphenyl-1-picryl hydrazyl (DPPH and measuring percent inhibition of peroxidation in linoleic acid system. The disc diffusion and modified resazurin microtitre-plate assays were used to evaluate the inhibition zones (IZ and minimum inhibitory concentration (MIC of R. officinalis essential oil, respectively. It is concluded from the results that Rosmarinus officinalis essential oil exhibited antiproliferative, antioxidant and antibacterial activities.

  16. Antibacterial activity and phytochemical analysis of Vochysia divergens (Vochysiaceae).

    Science.gov (United States)

    Hess, S C; Brum, R L; Honda, N K; Cruz, A B; Moretto, E; Cruz, R B; Messana, I; Ferrari, F; Cechinel Filho, V; Yunes, R A

    1995-07-07

    Vochysia divergens Pohl (Vochysiaceae) is a tree commonly found in wet soils of 'Pantanal' of Mato Grosso, Brazil, and used in folk medicine against infections and asthma. We have studied different extracts and some isolated compounds from this plant for antibacterial activity. From the extracts of the stem bark beta-sitosterol, betulinic acid and sericic acid were isolated. The minimal inhibitory concentration (MIC) for Staphylococcus aureus were: ethanolic extract (MIC = 1.5 mg/ml); ethyl acetate extract (MIC = 2.0 mg/ml); and sericic acid (MIC = 1.0 mg/ml). Escherichia coli was resistant until 5 mg/ml.

  17. Antibacterial activity of silver-killed bacteria: the "zombies" effect

    Science.gov (United States)

    Wakshlak, Racheli Ben-Knaz; Pedahzur, Rami; Avnir, David

    2015-04-01

    We report a previously unrecognized mechanism for the prolonged action of biocidal agents, which we denote as the zombies effect: biocidally-killed bacteria are capable of killing living bacteria. The concept is demonstrated by first killing Pseudomonas aeruginosa PAO1 with silver nitrate and then challenging, with the dead bacteria, a viable culture of the same bacterium: Efficient antibacterial activity of the killed bacteria is observed. A mechanism is suggested in terms of the action of the dead bacteria as a reservoir of silver, which, due to Le-Chatelier's principle, is re-targeted to the living bacteria. Langmuirian behavior, as well as deviations from it, support the proposed mechanism.

  18. EVALUATION OF ANTIBACTERIAL ACTIVITY OF CARALLUMA ADSCENDENS ROXB. STEM

    Directory of Open Access Journals (Sweden)

    Kulkarni Aditi S.

    2012-09-01

    Full Text Available Antibacterial activity of various extracts of stem of Caralluma adscendens var. fimbriata, Roxb., Family Asclepediaceae was studied against Bacillus pumilus, Escherichia coli, Staphylococcus aureus, Shigella sonnei. Among the various extracts petroleum ether extract is effective antimicrobial against S. aureus and E.coli while n- n-butanol extract is effective against Shigella sonnei and B. pumilus at a concentration of 5 mg/ml and 10 mg/ml. The inhibitory effect of various extracts was compared with standard antibiotic Gentamycin. MIC for both extracts was also determined.

  19. ANTIBACTERIAL ACTIVITY OF COMBINATION DRUGS FOR TREATING VAGINOSIS DIFFERENT ETIOLOGIES

    Directory of Open Access Journals (Sweden)

    Bobritskaya L. A.,

    2014-01-01

    Full Text Available Investigated the antimicrobial activity of the combination preparation in capsules "Meraflam" clinical of microbial strains isolated from patients with bacterial vaginosis . Experimentally proved the therapeutic dose of 0.3 g ornidazole in combination with Flamini 0.05 g, improve tolerability and expand the range of antibacterial action of the drug. In view of the antimicrobial capacity of diclofenac sodium from the combination of ofloxacin proposed for use in an integrated circuit - inflammatory treatment of infectious diseases , including bacterial vaginosis.

  20. Antibacterial activity in adhesive dentistry: a literature review.

    Science.gov (United States)

    Shafiei, Fereshteh; Memarpour, Mahtab

    2012-01-01

    This literature review summarizes the published research regarding the antibacterial agents used in adhesive dentistry. This article provides information about the clinical applications, beneficial effects, and possible disadvantages of antibacterials when used in various bonding situations.

  1. Antibacterial, antioxidant and cytotoxic activities of extracts from the ...

    African Journals Online (AJOL)

    HALA

    2012-10-11

    Oct 11, 2012 ... Full Length Research Paper. Antibacterial ... thermal energy production (as a source of heat) (Chaibi and Bourouni, 2005). ... this study was to evaluate a set of antibacterial and antioxidant ..... showed the highest free ABTS.

  2. Oxidative stress-mediated antibacterial activity of graphene oxide and reduced graphene oxide in Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Gurunathan S

    2012-11-01

    Full Text Available Sangiliyandi Gurunathan, Jae Woong Han, Ahmed Abdal Dayem, Vasuki Eppakayala, Jin-Hoi KimDepartment of Animal Biotechnology, Konkuk University, Seoul, South KoreaBackground: Graphene holds great promise for potential use in next-generation electronic and photonic devices due to its unique high carrier mobility, good optical transparency, large surface area, and biocompatibility. The aim of this study was to investigate the antibacterial effects of graphene oxide (GO and reduced graphene oxide (rGO in Pseudomonas aeruginosa. In this work, we used a novel reducing agent, betamercaptoethanol (BME, for synthesis of graphene to avoid the use of toxic materials. To uncover the impacts of GO and rGO on human health, the antibacterial activity of two types of graphene-based material toward a bacterial model P. aeruginosa was studied and compared.Methods: The synthesized GO and rGO was characterized by ultraviolet-visible absorption spectroscopy, particle-size analyzer, X-ray diffraction, scanning electron microscopy and Raman spectroscopy. Further, to explain the antimicrobial activity of graphene oxide and reduced graphene oxide, we employed various assays, such as cell growth, cell viability, reactive oxygen species generation, and DNA fragmentation.Results: Ultraviolet-visible spectra of the samples confirmed the transition of GO into graphene. Dynamic light-scattering analyses showed the average size among the two types of graphene materials. X-ray diffraction data validated the structure of graphene sheets, and high-resolution scanning electron microscopy was employed to investigate the morphologies of prepared graphene. Raman spectroscopy data indicated the removal of oxygen-containing functional groups from the surface of GO and the formation of graphene. The exposure of cells to GO and rGO induced the production of superoxide radical anion and loss of cell viability. Results suggest that the antibacterial activities are contributed to by loss of

  3. Synergistic Antibacterial Activity of the Essential Oil of Aguaribay (Schinus molle L.)

    OpenAIRE

    Lúcia A. Silva; Maria Silvia Guala; Heriberto Elder; David Díez; Jesus M. Rodilla; Pedro M. de Mendonça Rocha; Eunice Baltazar Pombo

    2012-01-01

    Schinus molle L. (aguaribay, aroeira-falsa, “molle”, family Anacardiaceae), a native of South America, produces an active antibacterial essential oil extracted from the leaves and fruits. This work reports a complete study of its chemical composition and determines the antibacterial activity of Schinus molle L. essential oil and its main components. The results showed that the crude extract essential oil has a potent antibacterial effect on Staphylococcus aureus ATCC 25923...

  4. Antibacterial activity of crude methanolic extract and fractions obtained from Larrea tridentata leaves

    OpenAIRE

    Martins, Silvia; Amorim,Elba L.C.; Sobrinho, Tadeu J. S. Peixoto; Saraiva, Antonio M.; Pisciottano, Maria N. C.; Aguilar, Cristóbal N.; Teixeira, J.A.; Mussatto, Solange I.

    2013-01-01

    The emergence of new infections and increase of bacteria drug-resistance rise up the urgent need for the development of new antibacterial agents from natural sources. This study was designed to evaluate the antibacterial activity of the crude methanolic extract (CME) and fractions [hexane (H), dichloromethane (DCM), ethyl acetate (EA) and ethanol (Et)] obtained from Larrea tridentata (Sessé & Moc. Ex DC.) Coville leaves. The antibacterial activity was determined by the agar diffusion method a...

  5. 基于人工神经网络的无机抗菌剂抗菌性能预测模型%Predictiong Model of Antibacterial Activities for Inorganic Antibacterial Agents Based on Artificial Neural Networks

    Institute of Scientific and Technical Information of China (English)

    刘雪峰; 张利; 涂铭旌

    2004-01-01

    Quantitatively evaluation of antibacterial activities of inorganic antibacterial agents is an urgent problem to be solved.Using experimental data by an orthogonal design, a prediction model of the relation between conditions of preparing inorganic antibacterial agents and their antibacterial activities has been developed.This is accomplished by introducing BP artificial neural networks in the study of inorganic antibacterial agents.It provides a theoretical support for the development and research on inorganic antibacterial agents.

  6. The Current Case of Quinolones: Synthetic Approaches and Antibacterial Activity

    Directory of Open Access Journals (Sweden)

    Abdul Naeem

    2016-03-01

    Full Text Available Quinolones are broad-spectrum synthetic antibacterial drugs first obtained during the synthesis of chloroquine. Nalidixic acid, the prototype of quinolones, first became available for clinical consumption in 1962 and was used mainly for urinary tract infections caused by Escherichia coli and other pathogenic Gram-negative bacteria. Recently, significant work has been carried out to synthesize novel quinolone analogues with enhanced activity and potential usage for the treatment of different bacterial diseases. These novel analogues are made by substitution at different sites—the variation at the C-6 and C-8 positions gives more effective drugs. Substitution of a fluorine atom at the C-6 position produces fluroquinolones, which account for a large proportion of the quinolones in clinical use. Among others, substitution of piperazine or methylpiperazine, pyrrolidinyl and piperidinyl rings also yields effective analogues. A total of twenty six analogues are reported in this review. The targets of quinolones are two bacterial enzymes of the class II topoisomerase family, namely gyrase and topoisomerase IV. Quinolones increase the concentration of drug-enzyme-DNA cleavage complexes and convert them into cellular toxins; as a result they are bactericidal. High bioavailability, relative low toxicity and favorable pharmacokinetics have resulted in the clinical success of fluoroquinolones and quinolones. Due to these superior properties, quinolones have been extensively utilized and this increased usage has resulted in some quinolone-resistant bacterial strains. Bacteria become resistant to quinolones by three mechanisms: (1 mutation in the target site (gyrase and/or topoisomerase IV of quinolones; (2 plasmid-mediated resistance; and (3 chromosome-mediated quinolone resistance. In plasmid-mediated resistance, the efflux of quinolones is increased along with a decrease in the interaction of the drug with gyrase (topoisomerase IV. In the case of

  7. The Current Case of Quinolones: Synthetic Approaches and Antibacterial Activity.

    Science.gov (United States)

    Naeem, Abdul; Badshah, Syed Lal; Muska, Mairman; Ahmad, Nasir; Khan, Khalid

    2016-03-28

    Quinolones are broad-spectrum synthetic antibacterial drugs first obtained during the synthesis of chloroquine. Nalidixic acid, the prototype of quinolones, first became available for clinical consumption in 1962 and was used mainly for urinary tract infections caused by Escherichia coli and other pathogenic Gram-negative bacteria. Recently, significant work has been carried out to synthesize novel quinolone analogues with enhanced activity and potential usage for the treatment of different bacterial diseases. These novel analogues are made by substitution at different sites--the variation at the C-6 and C-8 positions gives more effective drugs. Substitution of a fluorine atom at the C-6 position produces fluroquinolones, which account for a large proportion of the quinolones in clinical use. Among others, substitution of piperazine or methylpiperazine, pyrrolidinyl and piperidinyl rings also yields effective analogues. A total of twenty six analogues are reported in this review. The targets of quinolones are two bacterial enzymes of the class II topoisomerase family, namely gyrase and topoisomerase IV. Quinolones increase the concentration of drug-enzyme-DNA cleavage complexes and convert them into cellular toxins; as a result they are bactericidal. High bioavailability, relative low toxicity and favorable pharmacokinetics have resulted in the clinical success of fluoroquinolones and quinolones. Due to these superior properties, quinolones have been extensively utilized and this increased usage has resulted in some quinolone-resistant bacterial strains. Bacteria become resistant to quinolones by three mechanisms: (1) mutation in the target site (gyrase and/or topoisomerase IV) of quinolones; (2) plasmid-mediated resistance; and (3) chromosome-mediated quinolone resistance. In plasmid-mediated resistance, the efflux of quinolones is increased along with a decrease in the interaction of the drug with gyrase (topoisomerase IV). In the case of chromosome

  8. Synthesis and Antibacterial Activities of Some Schiff Bases

    Directory of Open Access Journals (Sweden)

    Mohamed N. Ibrahim

    2011-01-01

    Full Text Available Schiff bases p-hydroxybenzylidene-2-carboxyaniline, p-nitrobenz-ylidene-2-carboxyaniline, p-(N, N-dimethylaminobenzylidene-2-carboxyaniline, N-(4-hydroxybezylidene-benzene-1,2-diamine, N--(4-nitrobezylidenebenzene-1,2-diamine, N-(4-(N, N-dimethylaminobezylidenebenzene-1,2-diamine, N-(4-(N,N-dimethylaminobenzylidenenaphthalen-1-amine,N-(4-nitrobenzylidenenaphthalen-1-amine,N--(4-chlorobenzylidenenaphthalen-1-amine,sodium-4-(4-(N,N-dimethyl aminobenzylideneaminonaphthalene-1-sulfonate,sodium -4-(4-nitrobenzylidene-aminonaphthalene-1-sulfonate and sodium-4-(4-chlorobenzylideneamino naphthalene-1-sulfonate obtained by condensation of aniline and naphthyl-amine derivatives with some aromatic aldehydes were characterized by physical and spectral methods. The biological activity of these products were as antibacterial agents against three species of human pathogenic bacteria such as Escherichia coli, Staphylococcus aureus and Klebsiella sp. Nearly 50% of these compounds showed reasonable activity against the bacterial species investigated and we found that the antibacterial activity is dependent on the molecular structure of the compounds.

  9. Synergic antibacterial activity of some essential oils from Lamiaceae

    Directory of Open Access Journals (Sweden)

    Sh. Fahimi

    2015-05-01

    Full Text Available Background and objectives: Despite the vast production of new antibiotics in the last three decades, resistance to these drugs by microorganisms has increased and essential oils (EOs have been recognized to possess antimicrobial properties. Methods:  In the present study, EOs obtained from aerial parts of Thymus vulgaris L., Lavandula angustifolia Mill., Rosmarinus officinalis L. and Mentha piperita L., were evaluated for their single and binary combined antibacterial activities against four Gram-positive and Gram-negative pathogenic bacteria: Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Results: The results exhibited that some of the tested essential oils revealed antibacterial activities against the examined pathogens using broth microdilution method. Maximum activity of the testedessential oils was obtained from the combination of T. vulgaris and M. piperita essential oils against Staphylococcus aureus (MIC= 0.625 mg/mL. Conclusion: Combinations of the essential oils in this study showed synergic action against some pathogenic microorganisms which could be considered in medical and food industries as preservatives.

  10. Preparation and antibacterial activity of quaternized chitosan with iodine

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yang; Xie, Linlin; Sai, Mingze; Xu, Ningning; Ding, Derun, E-mail: dingderun@sues.edu.cn

    2015-03-01

    Chitosan (CTS) is a natural polymer with active groups such as –NH{sub 2} which can be functionalized to introduce new positively charged N-atoms and protonated amino group for better use. In this study, to improve the stability of iodine, a novel complex (CTS–CTA–I{sub 2}) was prepared by mixing N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride (CTS–CTA) with iodine in ethanol solution. The CTS–CTA–I{sub 2} was characterized by Fourier transform infrared spectra (FTIR), Ultraviolet and visible (UV–vis) spectra and thermal gravimetric analysis (TG). Besides, the interaction of iodine with CTS–CTA was also studied. The mole ratio of CTS–CTA with iodine was measured by iodometric titration method and the max mole ratio of CTS–CTA with iodine was 1:1.33. The antimicrobial activity of CTS, CTS–CTA and CTS–CTS–I{sub 2} complexes was investigated against Escherichia coli and Staphylococcus aureus and the antibacterial property of CTS–CTA–I{sub 2} was superior to CTS–CTA. - Highlights: • We prepared a novel iodine complex based on chitosan. • The CTS–CTA–I{sub 2} complex improved the stability of iodine. • The max mole ratio of CTS–CTA with iodine was 1:1.33. • The CTS–CTA–I{sub 2} complex showed significant antibacterial activity.

  11. Structure and antibacterial activity of Ce~(3+) exchanged montmorillonites

    Institute of Scientific and Technical Information of China (English)

    OUYANG Yousheng; XIE Yushan; TAN Shaozao; SHI Qingshan; CHEN Yiben

    2009-01-01

    Four kinds of Ce~(3+) exchanged montmorillonites(Ce/MMTs) were prepared by an ion-exchange reaction, and characterized with energy dispersive X-ray analysis (EDX), X-ray difference (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron micros-copy (SEM). The surface properties and antibacterial activity of Ce/MMTs were also investigated. The chemical compositions of Ce/MMTs were determined, and the cerium of Ce/MMTs was confirmed to be present as trivalent cerium state. The d001 basal spacings of Ce/MMTs were enlarged with the enhancement of the cerium contents, and the particles were formed with irregular shape. On increasing the Ce con-tents of Ce/MMTs, the special surface areas were decreased, but the total pore volumes and the average pore sizes were increased. The anti-bacterial activity of Ce/MMTs is increased with increasing the cerium contents, and 1.5g/L of Ce/MMT-3 containing 11.46wt.% of curium could remove all the Staphylococcus aureus and more than 99.9% of the Escherichia coli within 24.0 h of contact. Moreover, Ce/MMTs dis-played bactericidal activity.

  12. Antinociceptive, cytotoxic and antibacterial activities of Cleome viscosa leaves

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    Utpal Bose

    2011-02-01

    Full Text Available The methanol extract of the dried leaves of Cleome viscosa L., Cleomaceae, was investigated for its possible antinociceptive, cytotoxic and antibacterial activities in animal models. The extract produced significant writhing inhibition in acetic acid-induced writhing in mice at the oral doses of 250 and 500 mg/kg body weight (p<0.001 comparable to the standard drug diclofenac sodium at the dose of 25 mg/kg of body weight (p<0.001. The crude extract produced the most prominent cytotoxic activity against brine shrimp Artemia salina (LC50 28.18 μg/mL and LC90 112.20 μg/mL. The extract of C. viscosa L. exhibited significant in vitro antibacterial activity against Staphylococcus saprophyticus, Shigella sonnie, Salmonella typhi, Vibrio cholera, Streptococcus epidermidis, Shigella flexneri and Staphylococcus aureus with the zones of inhibition ranging from 10.76 to 16.34 mm. The obtained results provide a support for the use of this plant in traditional medicine and its further investigation.

  13. Both enhanced biocompatibility and antibacterial activity in Ag-decorated TiO2 nanotubes.

    Science.gov (United States)

    Lan, Ming-Ying; Liu, Chia-Pei; Huang, Her-Hsiung; Lee, Sheng-Wei

    2013-01-01

    In this study, Ag is electron-beam evaporated to modify the topography of anodic TiO2 nanotubes of different diameters to obtain an implant with enhanced antibacterial activity and biocompatibility. We found that highly hydrophilic as-grown TiO2 nanotubes became poorly hydrophilic with Ag incorporation; however they could effectively recover their wettability to some extent under ultraviolet light irradiation. The results obtained from antibacterial tests suggested that the Ag-decorated TiO2 nanotubes could greatly inhibit the growth of Staphylococcus aureus. In vitro biocompatibility evaluation indicated that fibroblast cells exhibited an obvious diameter-dependent behavior on both as-grown and Ag-decorated TiO2 nanotubes. Most importantly, of all samples, the smallest diameter (25-nm-diameter) Ag-decorated nanotubes exhibited the most obvious biological activity in promoting adhesion and proliferation of human fibroblasts, and this activity could be attributed to the highly irregular topography on a nanometric scale of the Ag-decorated nanotube surface. These experimental results demonstrate that by properly controlling the structural parameters of Ag-decorated TiO2 nanotubes, an implant surface can be produced that enhances biocompatibility and simultaneously boosts antibacterial activity.

  14. Synthesis of High Valence Silver-Loaded Mesoporous Silica with Strong Antibacterial Properties

    Science.gov (United States)

    Chen, Chun-Chi; Wu, Hsin-Hsien; Huang, Hsin-Yi; Liu, Chen-Wei; Chen, Yi-Ning

    2016-01-01

    A simple chemical method was developed for preparing high valence silver (Ag)-loaded mesoporous silica (Ag-ethylenediaminetetraacetic acid (EDTA)-SBA-15), which showed strong antibacterial activity. Ag-EDTA-SBA-15 exhibited stronger and more effective antibacterial activity than commercial Ag nanoparticles did, and it offered high stability of high valence silver in the porous matrix and long-lasting antibacterial activity. The synthesized materials were characterized using Fourier transform infrared spectroscopy, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) analysis, and transmission electron microscopy (TEM). Ag existed in both surface complexation and Ag particles. EDTA anchored within a porous structure chelated Ag ions in higher oxidation states and prevented their agglomeration and oxidation reduction. The XRD results showed that most Ag in the Ag-EDTA-SBA-15 existed in higher oxidation states such as Ag(II) and Ag(III). However, the XPS and TEM results showed that Ag easily reduced in lower oxidation states and agglomerated as Ag particles on the exterior layer of the SBA-15. PMID:26742050

  15. Synthesis of High Valence Silver-Loaded Mesoporous Silica with Strong Antibacterial Properties

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    Chun-Chi Chen

    2016-01-01

    Full Text Available A simple chemical method was developed for preparing high valence silver (Ag-loaded mesoporous silica (Ag-ethylenediaminetetraacetic acid (EDTA-SBA-15, which showed strong antibacterial activity. Ag-EDTA-SBA-15 exhibited stronger and more effective antibacterial activity than commercial Ag nanoparticles did, and it offered high stability of high valence silver in the porous matrix and long-lasting antibacterial activity. The synthesized materials were characterized using Fourier transform infrared spectroscopy, powder X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS analysis, and transmission electron microscopy (TEM. Ag existed in both surface complexation and Ag particles. EDTA anchored within a porous structure chelated Ag ions in higher oxidation states and prevented their agglomeration and oxidation reduction. The XRD results showed that most Ag in the Ag-EDTA-SBA-15 existed in higher oxidation states such as Ag(II and Ag(III. However, the XPS and TEM results showed that Ag easily reduced in lower oxidation states and agglomerated as Ag particles on the exterior layer of the SBA-15.

  16. Synthesis of High Valence Silver-Loaded Mesoporous Silica with Strong Antibacterial Properties.

    Science.gov (United States)

    Chen, Chun-Chi; Wu, Hsin-Hsien; Huang, Hsin-Yi; Liu, Chen-Wei; Chen, Yi-Ning

    2016-01-04

    A simple chemical method was developed for preparing high valence silver (Ag)-loaded mesoporous silica (Ag-ethylenediaminetetraacetic acid (EDTA)-SBA-15), which showed strong antibacterial activity. Ag-EDTA-SBA-15 exhibited stronger and more effective antibacterial activity than commercial Ag nanoparticles did, and it offered high stability of high valence silver in the porous matrix and long-lasting antibacterial activity. The synthesized materials were characterized using Fourier transform infrared spectroscopy, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) analysis, and transmission electron microscopy (TEM). Ag existed in both surface complexation and Ag particles. EDTA anchored within a porous structure chelated Ag ions in higher oxidation states and prevented their agglomeration and oxidation reduction. The XRD results showed that most Ag in the Ag-EDTA-SBA-15 existed in higher oxidation states such as Ag(II) and Ag(III). However, the XPS and TEM results showed that Ag easily reduced in lower oxidation states and agglomerated as Ag particles on the exterior layer of the SBA-15.

  17. Effect of an Antibacterial Monomer on the Antibacterial Activity of a Pit-and-Fissure Sealant

    Science.gov (United States)

    Dong, Yan; Zhang, Ling; Sun, Xiang; Liu, Zhengya; Guo, Huihui; Huang, Li; Chen, Jihua

    2016-01-01

    Resin-based pit-and-fissure sealants are often used to form a barrier on the occlusal surface of molars to treat caries lesions; however, bacteria can remain in the pit and fissures without detection, increasing the risk of secondary caries. Sealants with antimicrobial properties or microbial repellent actions might be advantageous. The aim of this study was to assess the inhibitory effect of a 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB)-incorporated sealant against Streptococcus mutans. MAE-DB (4% wt) was incorporated into a commercially available sealant, Eco-S resin-based pit-and-fissure sealant (Vericom Co., Ltd., Korea); a sealant without MAE-DB served as a negative control, and Clinpro™ Sealant (3M™ ESPE™), a fluoride-releasing resin, was used as a commercial control. The effects of the cured sealants and their eluents on the growth of S. mutans were determined according to colony-forming unit counts and metabolic tests. The effects of the cured sealants on the adherence and membrane integrity of S. mutans were investigated using confocal laser-scanning microscopy (CLSM) in conjunction with fluorescent indicators. Compared with the negative control and commercial control, the cured MAE-DB-incorporated pit-and-fissure sealant exhibited a significant inhibitory effect on the growth of S. mutans (P < 0.05), whereas the eluents did not show any detectable antibacterial activity. The commercial control also showed no detectable bactericidal activity. Moreover, the aged experimental material retained its property of contact inhibition of biofilm formation. The fluorescence analysis of CLSM images demonstrated that the cured MAE-DB-incorporated sealant could hamper the adherence of S. mutans and exert a detrimental effect on bacterial membrane integrity. The incorporation of MAE-DB can render a pit-and-fissure sealant with contact antibacterial activity after polymerization via influencing the growth, adherence, and membrane integrity of S

  18. Antibacterial activity of thyme and lavender essential oils.

    Science.gov (United States)

    Sienkiewicz, Monika; Łysakowska, Monika; Ciećwierz, Julita; Denys, Paweł; Kowalczyk, Edward

    2011-11-01

    Strong antiseptic activity of essential oils has been known for a long time. The antibacterial activity of oils was tested against clinical bacterial strains of Staphylococcus, Enterococcus, Escherichia and Pseudomonas genera. The agar diffusion method was used for microbial growth inhibition at various concentrations of the oils from T. vulgaris and L. angustifolia. Susceptibility testing to antibiotics and chemotherapeutics was carried out using disc-diffusion method. 120 strains of bacteria isolated from patients with infections of oral cavity, respiratory, genitourinary tracts and from hospital environment were investigated. The results of experiments showed that the oil from T. vulgaris exhibited extremely strong activity against all of the clinical strains. Thyme oil demonstrated a good efficacy against antibiotics resistant strains of the tested bacteria. Lavender oil has been less activity against clinical strains of Staphylococcus, Enterococcus and Escherichia genus. The worst results have been observed against all strains of Pseudomonas aeruginosa.

  19. Rational design of berberine-based FtsZ inhibitors with broad-spectrum antibacterial activity.

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    Ning Sun

    Full Text Available Inhibition of the functional activity of Filamenting temperature-sensitive mutant Z (FtsZ protein, an essential and highly conserved bacterial cytokinesis protein, is a promising approach for the development of a new class of antibacterial agents. Berberine, a benzylisoquinoline alkaloid widely used in traditional Chinese and native American medicines for its antimicrobial properties, has been recently reported to inhibit FtsZ. Using a combination of in silico structure-based design and in vitro biological assays, 9-phenoxyalkyl berberine derivatives were identified as potent FtsZ inhibitors. Compared to the parent compound berberine, the derivatives showed a significant enhancement of antibacterial activity against clinically relevant bacteria, and an improved potency against the GTPase activity and polymerization of FtsZ. The most potent compound 2 strongly inhibited the proliferation of Gram-positive bacteria, including methicillin-resistant S. aureus and vancomycin-resistant E. faecium, with MIC values between 2 and 4 µg/mL, and was active against the Gram-negative E. coli and K. pneumoniae, with MIC values of 32 and 64 µg/mL respectively. The compound perturbed the formation of cytokinetic Z-ring in E. coli. Also, the compound interfered with in vitro polymerization of S. aureus FtsZ. Taken together, the chemical modification of berberine with 9-phenoxyalkyl substituent groups greatly improved the antibacterial activity via targeting FtsZ.

  20. Antibacterial activity of Iranian medicinal plants against Streptococcus iniae isolated from rainbow trout (Oncorhynchus mykiss

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    Pirbalouti Ghasemi Abdollah

    2011-01-01

    Full Text Available Streptococcus iniae is among the major pathogens of a large number of fish species cultured in fresh and marine recirculating and net pen production systems. Ten Iranian medicinal plants were assessed for their antimicrobial activity against Streptococcus iniae isolates obtained from diseased Oncorhynchus mykiss (Salmonidae; Walbaum, 1972 collected from fish farms in Iran. The antibacterial activity of ethanol extracts of Punica granatum, Quercus branti, Glycyrrhiza glabra and essential oils of Heracleum lasiopetalum, Satureja bachtiarica, Thymus daenensis, Myrtus communis, Echinophora platyloba, Kelussia odoratissima and Stachys lavandulifolia against Steptococcus iniae was evaluated by disc diffusion and serial dilution assays. Most of the extracts and essential oils showed a relatively high antibacterial activity against Streptococcus iniae. Of the plants studied, the most active extracts were those obtained from the essential oils of Satureja bachtiarica, Echinophora platyloba, Thymus daenensis and the ethanol extract of Quercus branti. Some of the extracts were active against Streptococcus iniae. Two essential oils showed lower MIC values; Heracleum lasiopetalum (78 μg/ml and Satureja bachtiarica (39 μg/ml. The essential oil of Satureja bachtiarica could be an important source of antibacterial compounds against the Streptococcus iniae isolated from rainbow trout.

  1. Ultrathin hexagonal MgO nanoflakes coated medical textiles and their enhanced antibacterial activity

    Science.gov (United States)

    Veeran Ponnuvelu, Dinesh; Selvaraj, Aravind; Prema Suriyaraj, Shanmugam; Selvakumar, Rajendran; Pulithadathail, Biji

    2016-10-01

    A facile hydrothermal method for development of ultrathin MgO nanoplates from different precursors and their enhanced antibacterial activity after coating onto medical textiles is reported. Ultrathin MgO nanoplates having hexagonal structure were characterized using UV-visible spectroscopy, atomic force microscopy, field emission scanning electron microscopy, x-ray diffraction and high resolution transmission electron microscopy. The formation of MgO nanoplates was found to exhibit profound anionic effect leading to ultrathin, planar structures with exposed MgO [111] facets, which may be responsible for enhanced antimicrobial activity. Medical fabrics (bleached 100% cotton) were coated with MgO nanoplates using pad-dry-cure method. The antibacterial activity of these fabrics was tested against Bacillus subtilis and Escherichia coli. The MgO nanoplates coated onto the fabric were found to have good adherence properties owing to their two-dimensional structure and were durable even after repeated washings without substantial reduction in the antimicrobial activity. The enhanced antibacterial activity may be attributed to the presence of oxygen vacancies, surface oxygen anions and hydroxyl groups on the surface of MgO nanoplates. This cost-effective functional finish (anti-microbial) to cotton fabric using MgO nanoplates may be suitable for many prospective medical applications and can serve as an alternative to the costlier silver based antimicrobial textiles.

  2. Effect of coupling agent on nano-ZnO modification and antibacterial activity of ZnO/HDPE nanocomposite films

    Science.gov (United States)

    Li, Y. N.; Xu, W. M.; Zhang, G. Q.

    2015-07-01

    Commercial zinc oxide nanoparticles were modified by silane coupling agent of KH550 and KH560, respectively. The obtained nanocomposite was characterized by scanning electron microscopy (SEM), Thermogravimetric analyses (TGA) and apparent sedimentation stability (Sapp). Then, nano-ZnO/high-density polyethylene (HDPE) composite films were prepared via melt blending and a hot compression-molding process. The antibacterial testing of the films against E. coli and S. aureus was carried out via plate counting. SEM, TGA and Sapp suggest the modifier of silane changed the surface hydrophilicity and effectively broke the agglomerations of nanoparticles. Antibacterial testing results indicated the antibacterial rate of the films increased with increasing nano-ZnO content. At a low doped content of 0.2 wt%, the types of coupling agent influenced the antibacterial property with that of KH560-modified nano-ZnO/HDPE KH550-modified nano-ZnO/HDPE unmodified nano-ZnO/HDPE films. When the dosage nano-ZnO was over 0.2 wt%, the differences of antibacterial activity resulted by modification was concealed by the strong antibacterial activity with near 100% of the nano- ZnO/HDPE composite films.

  3. Chemical composition and antibacterial activity of the essential oil the leaf of Nepeta persica

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    Soraya AKHSHI

    2014-11-01

    Full Text Available The essential oil from the leaf of Nepeta persica Boiss, analyzed by gas chromatography (GC and gas chromatography (GC/mass spectrometry (MS, were shown to contain 4aα, 7α, 7aβ-nepetalactone (49.46% and 4aα, 7α, 7aα-nepetalactone (14.18%. The other main constituents were n-octane (13.10%, n-decane (3.67% and germacrene-D (2.04%. Antibacterial activities of the leaf oil were evaluated using the micro-dilution broth method. Inhibitory effects on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Salmonella typhi and Enterococcus faecalis were recorded. The leaf oil has difference activities against the test microorganisms. The antibacterial property of the essential oil might be ascribed to their high content of nepetalactone isomers.

  4. Cellulase-assisted extraction of polysaccharides from Cucurbita moschata and their antibacterial activity.

    Science.gov (United States)

    Qian, Zhi-Gang

    2014-01-30

    In this study, cellulase-assisted extraction of water soluble polysaccharides from pumpkin (Cucurbita moschata) and their antibacterial activity were investigated. The polysaccharides yield was monitored during the extraction process. The optimum extraction conditions were determined as follows: time, 40 min; temperature, 55°C; pH, 4.5; and cellulase amount, 4,000 U/g. The extracts were centrifuged, filtered, proteins removed by Sevag method, concentrated to approximately 15% (w/v), precipitated with 5 volumes of absolute ethanol, freeze-dried, and pulverized to yield a water soluble powder of pumpkin polysaccharides (PP). The sugar content of the product was 68.3%, and the yield was 17.34% (w/w), respectively. The PP had high antibacterial activity against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli at the concentration of 100 mg/mL.

  5. ANTIBACTERIAL ACTIVITY OF BENTHIC MARINE ALGAE EXTRACTS FROM THE MEDITERRANEAN COAST OF MOROCCO

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    Hanaâ Zbakh

    2012-08-01

    Full Text Available Marine organisms are potentially prolific sources of highly bioactive secondary metabolites that might represent useful leads in the development of new pharmaceutical agents. The Moroccan marine biodiversity including macroalgae remains partially unexplored in term of their potential bioactivities. Antibacterial activity of methanolic extracts from 20 species of macroalgae (9 Chlorophyta, 3 Phaeophyta and 8 Rhodophyta collected from Moroccan Mediterranean coasts was evaluated against Escherichia coli, Staphylococcus aureus and Enterococcus faecalis. The extracts of the studied Rhodophyceae inhibited considerably the growth of the three tested bacterial strains and gave inhibition zones between 20 and 24 mm. The results indicate that these species of seaweed present a significant capacity of antibacterial activities, which makes them interesting for screening for natural products.

  6. Cellulase-assisted extraction and antibacterial activity of polysaccharides from the dandelion Taraxacum officinale.

    Science.gov (United States)

    Wang, Hong-Bin

    2014-03-15

    In the present study, we investigated the cellulase-assisted extraction and antibacterial activity of water-soluble polysaccharides from the dandelion Taraxacum officinale. The extraction conditions, optimized for improving yield, were as follows: time, 46.11 min; temperature, 54.87 °C; pH, 4.51 and cellulase enzyme, 4000 U/g. Under these conditions, the yield of polysaccharides from dandelion (PD) reached 20.67% (w/w). The sugar content of PD was 95.6% (w/w), and it displayed high antibacterial activity at a concentration of 100mg/mL against Escherichia coli, Bacillus subtilis and Staphylococcus aureus. These results indicate that PD may be a viable option for use as a food preservative.

  7. Evaluation of the antibacterial activity of Ag/Fe3O4 nanocomposites synthesized using starch.

    Science.gov (United States)

    Ghaseminezhad, Seyedeh Masumeh; Shojaosadati, Seyed Abbas

    2016-06-25

    Ag/Fe3O4 nanocomposites were successfully synthesized by a facile and cost-effective method using starch. Starch acts as both a biocompatible capping agent for Fe3O4 nanoparticles and a reducing agent for the reduction of silver ions in an alkaline medium. Samples were characterized using several analytical techniques including field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic absorption spectroscopy (AAS), and Fourier-transform infrared (FT-IR) spectroscopy. The vibrating sample magnetometer revealed that the nanocomposites were superparamagnetic. The Ag/Fe3O4 nanocomposites demonstrated a high-antibacterial activity against Escherichia coli as evaluated by means of minimum inhibitory concentration. The characteristics and antibacterial activity of the nanocomposites were significantly influenced by the concentration of silver nitrate and pH.

  8. Antibacterial and cytotoxic activity of Brazilian plant extracts - Clusiaceae

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    Ivana B Suffredini

    2006-05-01

    Full Text Available Twelve extracts obtained from nine plants belonging to six different genera of Clusiaceae were analyzed against Gram-negative (Escherichia coli and Pseudomonas aeruginosa and Gram-positive (Staphylococcus aureus and Enterococcus faecalis bacteria using the microdilution broth assay. Tovomita aff. longifolia, T. brasiliensis, Clusia columnaris, Garcinia madruno, Haploclathra paniculata, and Caraipa grandifolia extracts showed significant results against the bacteria. The organic extract obtained from the leaves of T. aff. longifolia showed minimal inhibitory concentration (MIC = 70 µg/ml and minimal bactericidal concentration (MBC = 90 µg/ml against E. faecalis and the organic extract made with the stem of C. columnaris showed MIC = 180 µg/ml and MBC = 270 µg/ml against P. aeruginosa. None of the antibacterial extracts showed lethal activity against brine shrimp nauplii. On the other hand, both aqueous and organic extracts obtained from the aerial organs of Vismia guianensis that were cytotoxic to brine shrimp nauplii did not show a significant antibacterial activity in the assay.

  9. Antibacterial and cytotoxic activity of Brazilian plant extracts--Clusiaceae.

    Science.gov (United States)

    Suffredini, Ivana B; Paciencia, Mateus Lb; Nepomuceno, Daniela C; Younes, Riad N; Varella, Antonio D

    2006-05-01

    Twelve extracts obtained from nine plants belonging to six different genera of Clusiaceae were analyzed against Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus and Enterococcus faecalis) bacteria using the microdilution broth assay. Tovomita aff. longifolia, T. brasiliensis, Clusia columnaris, Garcinia madruno, Haploclathra paniculata, and Caraipa grandifolia extracts showed significant results against the bacteria. The organic extract obtained from the leaves of T. aff. longifolia showed minimal inhibitory concentration (MIC) = 70 microg/ml and minimal bactericidal concentration (MBC) = 90 microg/ml against E. faecalis and the organic extract made with the stem of C. columnaris showed MIC = 180 microg/ml and MBC = 270 microg/ml against P. aeruginosa. None of the antibacterial extracts showed lethal activity against brine shrimp nauplii. On the other hand, both aqueous and organic extracts obtained from the aerial organs of Vismia guianensis that were cytotoxic to brine shrimp nauplii did not show a significant antibacterial activity in the assay.

  10. Mode of antibacterial activity of Eclalbasaponin isolated from Eclipta alba.

    Science.gov (United States)

    Ray, A; Bharali, P; Konwar, B K

    2013-12-01

    The present study was undertaken to evaluate the mode of antibacterial activity of Eclalbasaponin isolated from Eclipta alba, against selected Gram-positive and Gram-negative bacteria. The probable chemical structure was determined by using various spectroscopic techniques such as Fourier transform infrared spectroscopy (FTIR) and mass spectroscopy. The antibacterial activity was evaluated by well diffusion technique, pH sensitivity, chemotaxis, and crystal violet assays. Eclalbasaponin showed clear zone of inhibition against both Bacillus subtilis and Pseudomonas aeruginosa and exhibited growth inhibition at the pH range of 5.5-9.0. The isolated saponin exhibited its positive chemoattractant property for both bacterial strains. Results of crystal violet assay and the presence of UV-sensitive materials in the cell-free supernatant confirmed the cellular damages caused by the treatment of Eclalbasaponin. The release of intracellular proteins due to the membrane damage was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Changes in the cell surface structure and membrane disruption were further revealed by FTIR and scanning electron microscopy analysis. The present study suggests that the isolated saponin from E. alba causes the disruption of the bacterial cell membrane which leads to the loss of bacterial cell viability.

  11. Improving antibacterial activity of Spathodea campanulata Beauv's water extract with copper nanoparticle on Staphylococcus aureus

    Science.gov (United States)

    Masruri, Masruri; Baihaqi, Muchammad Abdi; Riyanto, Slamet; Srihardyastutie, Arie

    2017-03-01

    This finding reports an antibacterial activity of water extract from the stem bark of Spathodea campanulata Beauv by combining it to the copper nanoparticle. The strategy involves extraction, characterization, and evaluation of water extract of Spathodea campanulata Beauv as an antibacterial agent. Includes, its pre-mixture with copper nanoparticle. In short, antibacterial activity of the mixture of water extract and copper nanoparticle inhibit the growth of Staphylococcus aureus three times higher than that using water extract. The result significantly paves the way for further application of Spathodea campanulata stem bark waste as antibacterial materials.

  12. Antibacterial activity of Beta vulgaris L. pomace extract

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    Velićanski Aleksandra S.

    2011-01-01

    Full Text Available Antibacterial activity of Beta vulgaris L. (beetroot pomace extract (concentration 100 mg/ml was tested against five Gram positive and seven Gram negative bacterial strains (reference cultures and natural isolates. Disc diffusion method with 15 µl of extract and agar-well diffusion method with 50 and 100 µl were used. Antibiotic (cefotaxime/clavulanic acid was used as a control sample. The tested extract showed the highest activity against Staphylococcus aureus and Bacillus cereus, where clear zones (without growth appeared. There was no any activity against other tested Gram-positive bacteria, except for Staphylococcus epidermidis, with a small zone of reduced growth. Growth of all tested Gram-negative bacteria was inhibited usually with 100 µl of extract. The most susceptible were Citrobacter freundii and Salmonella typhymurium. The tested antibiotic gave clear, usually large zones for all tested strains except for Staphylococcus cohni spp. cohni, where only a zone of reduced growth appeared.

  13. QSAR MODELING OF ANTIBACTERIAL ACTIVITY OF SOME BENZIMIDAZOLE DERIVATIVES

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    SANJA O. PODUNAVAC-KUZMANOVIĆ

    2011-03-01

    Full Text Available A quantitative structure-activity relationship (QSAR study has been carried out for a training set of 12 benzimidazole derivatives to correlate and predict the antibacterial activity of studied compounds against Gram-negative bacteria Pseudomonas aeruginosa. Multiple linear regression was used to select the descriptors and to generate the best prediction model that relates the structural features to inhibitory activity. The predictivity of the model was estimated by cross-validation with the leave-one-out method. Our results suggest a QSAR model based on the following descriptors: parameter of lipophilicity (logP and hydration energy (HE. Good agreement between experimental and predicted inhibitory values, obtained in the validation procedure, indicated the good quality of the generated QSAR model.

  14. Antibacterial activity of chemical constituents isolated from Asparagus racemosus

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    Muhammad Abdullah Shah

    2014-03-01

    Full Text Available Asparagus racemosus is a medical extensively used in traditional medicine for various disorders including its use in infectious. So far work has been done to identify its active constituents responsible for antiseptic folk use of this plant. In the current investigation, we have made an effort to identify its chemical constituents that might be partly responsible for antimicrobial properties. Extraction and isolation of plant extract lead to isolation of two nor-lignans and two steroidal triterpenes (compound 1 to 4. All compound showed considerable antibacterial activities against E. coli and S. aureus while no significant activity was observed against S. typhi. This study highlighted the potential of A. racemosus to be further explored as a source of bioactive natural products.

  15. Liposome containing cinnamon oil with antibacterial activity against methicillin-resistant Staphylococcus aureus biofilm.

    Science.gov (United States)

    Cui, Haiying; Li, Wei; Li, Changzhu; Vittayapadung, Saritporn; Lin, Lin

    2016-01-01

    The global burden of bacterial disease remains high and is set against a backdrop of increasing antimicrobial resistance. There is a pressing need for highly effective and natural antibacterial agents. In this work, the anti-biofilm effect of cinnamon oil on methicillin-resistant Staphylococcus aureus was evaluated. Then, cinnamon oil was encapsulated in liposomes to enhance its chemical stability. The anti-biofilm activities of the liposome-encapsulated cinnamon oil against MRSA biofilms on stainless steel, gauze, nylon membrane and non-woven fabrics were evaluated by colony forming unit determination. Scanning electron microscopy and laser scanning confocal microscopy analyses were employed to observe the morphological changes in MRSA biofilms treated with the encapsulated cinnamon oil. As a natural and safe spice, the cinnamon oil exhibited a satisfactory antibacterial performance on MRSA and its biofilms. The application of liposomes further improves the stability of antimicrobial agents and extends the action time.

  16. Particle-cell contact enhances antibacterial activity of silver nanoparticles.

    Directory of Open Access Journals (Sweden)

    Olesja Bondarenko

    Full Text Available BACKGROUND: It is generally accepted that antibacterial properties of Ag nanoparticles (AgNPs are dictated by their dissolved fraction. However, dissolution-based concept alone does not fully explain the toxic potency of nanoparticulate silver compared to silver ions. METHODOLOGY/PRINCIPAL FINDINGS: Herein, we demonstrated that the direct contact between bacterial cell and AgNPs' surface enhanced the toxicity of nanosilver. More specifically, cell-NP contact increased the cellular uptake of particle-associated Ag ions - the single and ultimate cause of toxicity. To prove that, we evaluated the toxicity of three different AgNPs (uncoated, PVP-coated and protein-coated to six bacterial strains: Gram-negative Escherichia coli, Pseudomonas fluorescens, P. putida and P. aeruginosa and Gram-positive Bacillus subtilis and Staphylococcus aureus. While the toxicity of AgNO3 to these bacteria varied only slightly (the 4-h EC50 ranged from 0.3 to 1.2 mg Ag/l, the 4-h EC50 values of protein-coated AgNPs for various bacterial strains differed remarkably, from 0.35 to 46 mg Ag/l. By systematically comparing the intracellular and extracellular free Ag(+ liberated from AgNPs, we demonstrated that not only extracellular dissolution in the bacterial test environment but also additional dissolution taking place at the particle-cell interface played an essential role in antibacterial action of AgNPs. The role of the NP-cell contact in dictating the antibacterial activity of Ag-NPs was additionally proven by the following observations: (i separation of bacterial cells from AgNPs by particle-impermeable membrane (cut-off 20 kDa, ∼4 nm significantly reduced the toxicity of AgNPs and (ii P. aeruginosa cells which tended to attach onto AgNPs, exhibited the highest sensitivity to all forms of nanoparticulate Ag. CONCLUSIONS/SIGNIFICANCE: Our findings provide new insights into the mode of antibacterial action of nanosilver and explain some discrepancies in this field

  17. Antibacterial and antifungal activities of the endemic species Glaucium vitellinum Boiss. and Buhse

    Directory of Open Access Journals (Sweden)

    Mina Mehrara

    2014-12-01

    Full Text Available Objectives: Belonging to Papaveraceae family, Glaucium vitellinum is one of the Persian endemic plants which has not been investigated biologically. The present paper focused on the assessment of the antibacterial and antifungal activities of the total methanol extract and alkaloid sub-fraction of the flowering aerial parts of G. vitellinum. Materials and Methods: The antibacterial and antifungal activities were investigated using cup plate method and disc diffusion assay, respectively. The MIC values of the active samples were determined using micro plate dilution method. Results: The crude extract and alkaloid sub-fraction of G. vitellinum had significant inhibition activity on the growth of S. aureus and S. typhi. From antifungal assay, it is concluded that only the yeast C. albicans, showed a high sensitivity to the extract and especially to the related alkaloid sub-fraction. Conclusions: Regarding the results, G. vitellinum could be employed as a natural antibacterial and antifungal agent against S. aureus, S. typhi, and C. albicans, respectively. Moreover, based on the results of this study, further in vivo and ex vivo confirmatory tests for total methanol extract and alkaloid sub-fraction are recommended.

  18. Enhancement of the Antibacterial Activity of Silver Nanoparticles against Phytopathogenic Bacterium Ralstonia solanacearum by Stabilization

    Directory of Open Access Journals (Sweden)

    Juanni Chen

    2016-01-01

    Full Text Available In this paper, the enhanced antibacterial activity of silver nanoparticles (AgNPs against the phytopathogenic bacterium Ralstonia solanacearum after stabilization using selected surfactants (SDS, SDBS, TX-100, and Tween 80 was examined, in comparison with silver ion. Tween 80 was found to be the most preferable stabilizer of AgNPs due to the beneficial synergistic effects of the AgNPs and surfactant. However, all the surfactants nearly had no effects on the antibacterial activity of Ag+. In vitro, Tween 80-stabilized AgNPs showed the highest bactericidal activity against R. solanacearum. Further measurements using TEM, fluorescence microscopy, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE revealed that though Ag+ and Tween 80-Ag+ induced high toxicity, Tween 80-stabilized AgNPs displayed most severe damage when in direct contact with cells, causing mechanistic injury to the cell membrane and strongly modifying and destructing the cellular proteins. Meanwhile, in vivo, the pot experiments data indicated that the control efficiency of Tween 80-stabilized AgNPs on tobacco bacterial wilt was 96.71%, 90.11%, and 84.21%, at 7 days, 14 days, and 21 days, respectively. Based on the results evidencing their advantageous low dosage requirements and strong antimicrobial activity, Tween 80-stabilized AgNPs are a promising antibacterial agent for use in alternative crop disease control approaches.

  19. Identification of the phenolic compounds contributing to antibacterial activity in ethanol extracts of Brazilian red propolis.

    Science.gov (United States)

    Inui, Saori; Hatano, Ai; Yoshino, Megumi; Hosoya, Takahiro; Shimamura, Yuko; Masuda, Shuichi; Ahn, Mok-Ryeon; Tazawa, Shigemi; Araki, Yoko; Kumazawa, Shigenori

    2014-01-01

    The purpose of this study is to identify the quantity and antibacterial activity of the individual phenolic compounds in Brazilian red propolis. Quantitative analysis of the 12 phenolic compounds in Brazilian red propolis was carried out using reversed-phase high-performance liquid chromatography. The main phenolic compounds in Brazilian red propolis were found to be (3S)-vestitol (1), (3S)-neovestitol (2) and (6aS,11aS)-medicarpin (4) with quantities of 72.9, 66.9 and 30.8 mg g of ethanol extracts(- 1), respectively. Moreover, the antibacterial activities of each compound against Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa were evaluated by measuring the minimum inhibitory concentrations. In particular, compound 4 exhibited the most potent antibacterial activity among all the assayed compounds against selected bacteria, indicating that 4 is the most active compound in Brazilian red propolis extracts. Thus, Brazilian red propolis may be used as food additives and pharmaceuticals to protect against bacteria.

  20. Deodorant effects of a sage extract stick: Antibacterial activity and sensory evaluation of axillary deodorancy

    OpenAIRE

    Mohammad Ali Shahtalebi; Mustafa Ghanadian; Ali Farzan; Niloufar Shiri; Dariush Shokri; Syed Ali Fatemi

    2013-01-01

    Background: Deodorant products prevent the growth and activity of the degrading apocrine gland bacteria living in the armpit. Common antibacterial agents in the market like triclosan and aluminum salts, in spite of their suitable antibacterial effects, increase the risk of Alzheimer′s disease, breast and prostate cancers or induce contact dermatitis. Therefore, plant extracts possessing antibacterial effects are of interest. The aim of the present study was to verify the in vitro antimicrobia...

  1. Chemical composition and antibacterial activity of essential oils from the Tunisian Allium nigrum L.

    OpenAIRE

    Rouis-Soussi, Lamia Sakka; Ayeb-Zakhama, El Asma; Mahjoub, Aouni; Flamini, Guido; Jannet, Hichem Ben; Harzallah-Skhiri, Fethia

    2014-01-01

    The chemical composition of the essential oils of different Allium nigrum L. organs and the antibacterial activity were evaluated. The study is particularly interesting because hitherto there are no reports on the antibacterial screening of this species with specific chemical composition. Therefore, essential oils from different organs (flowers, stems, leaves and bulbs) obtained separately by hydrodistillation were analyzed using gas chromatography–mass spectrometry (GC–MS). The antibacterial...

  2. Antibacterial and antioxidant activities of hydroalcoholic stem bark extract ofSchotia latifolia Jacq

    Institute of Scientific and Technical Information of China (English)

    Sunday Oyewole Oyedemi; Anthony Jide Afolayan

    2011-01-01

    Objective:To investigate the antibacterial and antioxidant activities of hydroalcoholic extract ofSchotia latifolia (S. latifolia) bark commonly used in South Africa traditional medicine for the treatment of various ailments.Methods: The antibacterial test andMIC was determined by using agar well diffusion and dilution methods respectively against eight strains of bacteria. The total phenol, proanthocyanidin and flavonoid contents ofS. latifolia were assessed using standard methods. The antioxidant activity of the extract was evaluated using ferric reducing power and the free radical scavenging activity against1,1-diphenyl-2-picrylhydrazyl(DPPH), 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic-acid(ABTS), nitric oxide(NO), hydrogen peroxide(H2O2)and lipid oxidation(LO).Results:The antibacterial activity demonstrated an appreciable effect against all the gram positive bacteria atMIC between0.016 and10 mg/mL while that of gram negative bacteria was above10 mg/mL. The plant extract exhibited high concentration of proanthocyanidin [(300.00±0.10) mgCE/g], followed by flavonoid [(12.46±0.04 mg) TE/g] and phenol [(11.06±0.03) mgQE/g] contents. Similarly, the extract at0.5 mg/mL scavenges DPPH, ABTS, H2O2, LO andNO by87.55%, 89.47%, 77.15%, 86.48% and77.75% of the radicals respectively. The reducing power was also found to be concentration dependent.Conclusions:Our data suggest thatS. latifolia extract has antibacterial and antioxidants activity and thus could be used as alternative therapy against antibiotic resistance bacteria and to prevent many radical related diseases.

  3. Anti-adhesion and antibacterial activity of silver nanoparticles supported on graphene oxide sheets.

    Science.gov (United States)

    de Faria, Andreia Fonseca; Martinez, Diego Stéfani Teodoro; Meira, Stela Maris Meister; de Moraes, Ana Carolina Mazarin; Brandelli, Adriano; Filho, Antonio Gomes Souza; Alves, Oswaldo Luiz

    2014-01-01

    This work reports on the preparation, characterization and antibacterial activity of a nanocomposite formed from graphene oxide (GO) sheets decorated with silver nanoparticles (GO-Ag). The GO-Ag nanocomposite was prepared in the presence of AgNO3 and sodium citrate. The physicochemical characterization was performed by UV-vis spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), Raman spectroscopy and transmission electron microscopy (TEM). The average size of the silver nanoparticles anchored on the GO surface was 7.5 nm. Oxidation debris fragments (a byproduct adsorbed on the GO surface) were found to be crucial for the nucleation and growth of the silver nanoparticles. The antibacterial activity of the GO and GO-Ag nanocomposite against the microorganism Pseudomonas aeruginosa was investigated using the standard counting plate methodology. The GO dispersion showed no antibacterial activity against P. aeruginosa over the concentration range investigated. On the other hand, the GO-Ag nanocomposite displayed high biocidal activity with a minimum inhibitory concentration ranging from 2.5 to 5.0 μg/mL. The anti-biofilm activity toward P. aeruginosa adhered on stainless steel surfaces was also investigated. The results showed a 100% inhibition rate of the adhered cells after exposure to the GO-Ag nanocomposite for one hour. To the best of our knowledge, this work provides the first direct evidence that GO-Ag nanocomposites can inhibit the growth of microbial adhered cells, thus preventing the process of biofilm formation. These promising results support the idea that GO-Ag nanocomposites may be applied as antibacterial coatings material to prevent the development of biofilms in food packaging and medical devices.

  4. Antibacterial activity and mechanism of berberine against Streptococcus agalactiae.

    Science.gov (United States)

    Peng, Lianci; Kang, Shuai; Yin, Zhongqiong; Jia, Renyong; Song, Xu; Li, Li; Li, Zhengwen; Zou, Yuanfeng; Liang, Xiaoxia; Li, Lixia; He, Changliang; Ye, Gang; Yin, Lizi; Shi, Fei; Lv, Cheng; Jing, Bo

    2015-01-01

    The antibacterial activity and mechanism of berberine against Streptococcus agalactiae were investigated in this study by analyzing the growth, morphology and protein of the S. agalactiae cells treated with berberine. The antibacterial susceptibility test result indicated minimum inhibition concentration (MIC) of berberine against Streptococcus agalactiae was 78 μg/mL and the time-kill curves showed the correlation of concentration-time. After the bacteria was exposed to 78 μg/mL berberine, the fragmentary cell membrane and cells unequal division were observed by the transmission electron microscopy (TEM), indicating the bacterial cells were severely damaged. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) study demonstrated that berberine could damage bacterial cells through destroying cellular proteins. Meanwhile, Fluorescence microscope revealed that berberine could affect the synthesis of DNA. In conclusion, these results strongly suggested that berberine may damage the structure of bacterial cell membrane and inhibit synthesis of protein and DNA, which cause Streptococcus agalactiae bacteria to die eventually.

  5. Antibacterial activity and biodegradability assessment of chemically grafted nanofibrillated cellulose.

    Science.gov (United States)

    Missoum, Karim; Sadocco, Patrizia; Causio, Jessica; Belgacem, Mohamed Naceur; Bras, Julien

    2014-12-01

    Nanofibrillated cellulose (NFC) and their derivatives were prepared using three chemical surface modification strategies. All grafting was characterized by FTIR and contact angle measurements in order to evaluate the efficiency of grafting. Antibacterial activities of neat and grafted samples were investigated against two kinds of bacteria (i.e. Gram+ (Staphylococcus aureus) and Gram- (Klebsiella pneumoniae)). All the grafted samples displayed promising results with at least bacteriostatic effect or bactericidal properties. They also strongly enhanced the photo-catalytic antimicrobial effect of TiO2. This study proves that it is better to use grafted NFC either alone or for functionalization with TiO2 if anti-bacterial properties are desired. The cellulose backbone is known to be easily biodegradable in different biodegradation conditions and environments. The chemical surface modifications applied on NFC in the present work did not negatively influence this valuable property of cellulose but help for monitoring this property, which could be very useful for paper, packaging and composites. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Antibacterial activity of caffeine against plant pathogenic bacteria.

    Science.gov (United States)

    Sledz, Wojciech; Los, Emilia; Paczek, Agnieszka; Rischka, Jacek; Motyka, Agata; Zoledowska, Sabina; Piosik, Jacek; Lojkowska, Ewa

    2015-01-01

    The objective of the present study was to evaluate the antibacterial properties of a plant secondary metabolite - caffeine. Caffeine is present in over 100 plant species. Antibacterial activity of caffeine was examined against the following plant-pathogenic bacteria: Ralstonia solanacearum (Rsol), Clavibacter michiganesis subsp. sepedonicus (Cms), Dickeya solani (Dsol), Pectobacterium atrosepticum (Pba), Pectobacterium carotovorum subsp. carotovorum (Pcc), Pseudomonas syringae pv. tomato (Pst), and Xanthomonas campestris subsp. campestris (Xcc). MIC and MBC values ranged from 5 to 20 mM and from 43 to 100 mM, respectively. Caffeine increased the bacterial generation time of all tested species and caused changes in cell morphology. The influence of caffeine on the synthesis of DNA, RNA and proteins was investigated in cultures of plant pathogenic bacteria with labelled precursors: [(3)H]thymidine, [(3)H]uridine or (14)C leucine, respectively. RNA biosynthesis was more affected than DNA or protein biosynthesis in bacterial cells treated with caffeine. Treatment of Pba with caffeine for 336 h did not induce resistance to this compound. Caffeine application reduced disease symptoms caused by Dsol on chicory leaves, potato slices, and whole potato tubers. The data presented indicate caffeine as a potential tool for the control of diseases caused by plant-pathogenic bacteria, especially under storage conditions.

  7. Cyclodextrin modified PLLA parietal reinforcement implant with prolonged antibacterial activity.

    Science.gov (United States)

    Vermet, G; Degoutin, S; Chai, F; Maton, M; Flores, C; Neut, C; Danjou, P E; Martel, B; Blanchemain, N

    2017-02-12

    The use of textile meshes in hernia repair is widespread in visceral surgery. Though, mesh infection is a complication that may prolong the patient recovery period and consequently presents an impact on public health economy. Such concern can be avoided thanks to a local and extended antibiotic release on the operative site. In recent developments, poly-l-lactic acid (PLLA) has been used in complement of polyethyleneterephthalate (Dacron®) (PET) or polypropylene (PP) yarns in the manufacture of semi-resorbable parietal implants. The goal of the present study consisted in assigning drug reservoir properties and prolonged antibacterial effect to a 100% PLLA knit through its functionalization with a cyclodextrin polymer (polyCD) and activation with ciprofloxacin. The study focused i) on the control of degree of polyCD functionalization of the PLLA support and on its physical and biological characterization by Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC) and cell viability, ii) on the understanding of drug/meshes interaction using mathematic model and iii) on the correlation between drug release studies in phosphate buffer saline (PBS) and microbiological evaluation of meshes and release medium against E. coli and S. aureus. All above mentioned tests highlighted the contribution of polyCD on the improved performances of the resulting antibacterial implantable material.

  8. Screening for antibacterial principle and activity of Aerva javanica (Burm .f) Juss. ex Schult.

    Institute of Scientific and Technical Information of China (English)

    P Srinivas; S Ram Reddy

    2012-01-01

    Objective: To investigate the antibacterial principle and activity of Aerva javanica, a medicinal plant. Methods: Crude extracts of different parts of Aerva javanica were made with hexane, chloroform and methanol. Phytochemical analysis of the crude extracts was done by following the standard methodology, and antibacterial activity was evaluated by inhibition zone and MIC values. Crude extracts were resolved through HPTLC and the antibacterial activity of the separated compounds was evaluated by bioautography. Results: The yields of crude extracts made from different plant parts varied both with plant part and solvent. Methanolic extracts of leaf and flower have shown a wide range of phytochemicals and more antibacterial activity. HPTLC separation of extracts coupled with bioautography studies revealed that apigenin followed by rutin and kaempferol has shown antibacterial activity against more number of bacteria. Conclusions:The present study supports the use of Aerva javanica in the traditional medicine, and it can be used against bacterial infections.

  9. Anti-bacterial activity of the methanolic extract of leucas hyssopifolia (Benth.

    Directory of Open Access Journals (Sweden)

    Devendra Mishra

    2013-01-01

    Full Text Available Context: Methanolic extract of Leucas hyssopifolia roots was investigated for its anti-bacterial property. Aim: Evaluation of anti-bacterial activity of Leucas hyssopifolia Benth. Settings and Design: Roots of the plant were collected, extracted and finally evaluated for their anti-bacterial activity. Materials and Methods: Paper disc diffusion method and microdilution technique were employed for the determination of zone of inhibition and minimal inhibitory concentration, respectively. Results: The extract showed anti-bacterial activity against all the tested bacterial strains except Escherichia coli. Conclusions: Anti-bacterial activity of extract of Leucas hyssopifolia roots may be due to the presence of secondary plant metabolites like terpenoids, steroids and flavonoids, which are present in the extract. The extract can be further studied for the isolation of chemical compounds and their biological activity.

  10. Anacardic acid derivatives from Brazilian propolis and their antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

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

  11. Influence of glucosamine on oligochitosan solubility and antibacterial activity.

    Science.gov (United States)

    Blagodatskikh, Inesa V; Kulikov, Sergey N; Vyshivannaya, Oxana V; Bezrodnykh, Evgeniya A; Yamskov, Igor A; Tikhonov, Vladimir E

    2013-11-15

    Light scattering studies indicate that oligochitosan (short-chain chitosan) solutions contain aggregates at pH values below the critical pH of phase separation, while at or above this point the gel phase coexists with the aggregate solution. This work demonstrates for the first time that the presence of D-glucosamine in an oligochitosan solution shifts the critical pH to a higher value and improves the oligochitosan antibacterial activity against Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermis in neutral and slightly alkaline aqueous media. By comparing the results of light scattering studies and antimicrobial assays one can conclude that the antimicrobial activity of oligochitosan is dependent on its unimolecular form, not its supramolecular structures. The widening of the homogeneity region of an oligochitosan solution could lead to promising biomedical applications.

  12. Antibacterial activity of fourGracilaria species of red seaweeds collected from Mandapam Coast, Gulf of Mannar Marine Biosphere Reserve, India

    Institute of Scientific and Technical Information of China (English)

    Sethu Rameshkumar; Kolidoss Radhakrishnan; Arasan Sreenivasan; Samraj Aanand

    2016-01-01

    Objective:To study the antibacterial activities of diethyl ether, toluene, ethanol and methanol extracts of red seaweeds such asGracilaria crassa(G. crassa),Gracilaria folifera(G. folifera), Gracilaria debilis (G. debilis) andGracilaria corticata. Methods:The crude extracts were tested against different types of Gram-positive and -negative bacterial strains and all the seaweed extracts were tested a broad spectrum of antibacterial activity. Antibacterial activity was made using paper disc diffusion method. Four organic solvents (diethyl ether, toluene, methanol and ethanol) were used separately in a Soxhlet apparatus for seven bacterial strains. Antibacterial activity of the known antibiotics such as chloramphenicol, streptomycin, kanamycin and ampicillin was determined by testing them against different test organisms. Results:The high antibacterial activity was noted in the extracts ofG. crassa,G. folifera andG. debilis. However,G. crassa andG. debilis have good antibacterial activity. Pathogens likeBacillus subtilis andEscherichia coli were less susceptible to the methanol and diethyl ether extracts ofG. folifera. The comparative study on the antibacterial activity was also made by using 200μg concentration of solvent extracts (diethyl ether, ethanol, toluene and methanol)and different five antibiotics such as chloramphenicol, streptomycin, kanamycin, amoxicillin and ampicillin. The bacterial strains tested were more sensitive to chloramphenicol, streptomycin, kanamycin, and ampicillin when compared to algal extracts. Conclusions: The present study proved that the extracts ofG. crassa,G. folifera andG. debilis have high antibacterial activity. AlthoughG. crassa andG. debilis showed good antibacterial activity, many known antibiotics are active against a few organisms individually. Hence, the extracts of seaweeds were active against all test organisms used and the activities were comparable to that of antibiotics and the seaweeds offer a feasible alternative for

  13. Antibacterial activity of two-dimensional MoS2 sheets

    Science.gov (United States)

    Yang, Xi; Li, Jie; Liang, Tao; Ma, Chunyan; Zhang, Yingying; Chen, Hongzheng; Hanagata, Nobutaka; Su, Huanxing; Xu, Mingsheng

    2014-08-01

    Graphene-like two-dimensional materials (2DMats) show application potential in optoelectronics and biomedicine due to their unique properties. However, environmental and biological influences of these 2DMats remain to be unveiled. Here we reported the antibacterial activity of two-dimensional (2D) chemically exfoliated MoS2 (ce-MoS2) sheets. We found that the antibacterial activity of ce-MoS2 sheets was much more potent than that of the raw MoS2 powders used for the synthesis of ce-MoS2 sheets possibly due to the 2D planar structure (high specific surface area) and higher conductivity of the ce-MoS2. We investigated the antibacterial mechanisms of the ce-MoS2 sheets and proposed their antibacterial pathways. We found that the ce-MoS2 sheets could produce reactive oxygen species (ROS), different from a previous report on graphene-based materials. Particularly, the oxidation capacity of the ce-MoS2 sheets toward glutathione oxidation showed a time and concentration dependent trend, which is fully consistent with the antibacterial behaviour of the ce-MoS2 sheets. The results suggest that antimicrobial behaviors were attributable to both membrane and oxidation stress. The antibacterial pathways include MoS2-bacteria contact induced membrane stress, superoxide anion (O2&z.rad;-) induced ROS production by the ce-MoS2, and the ensuing superoxide anion-independent oxidation. Our study thus indicates that the tailoring of the dimension of nanomaterials and their electronic properties would manipulate antibacterial activity.Graphene-like two-dimensional materials (2DMats) show application potential in optoelectronics and biomedicine due to their unique properties. However, environmental and biological influences of these 2DMats remain to be unveiled. Here we reported the antibacterial activity of two-dimensional (2D) chemically exfoliated MoS2 (ce-MoS2) sheets. We found that the antibacterial activity of ce-MoS2 sheets was much more potent than that of the raw MoS2 powders

  14. Determination of antibacterial, antifungal activity and chemical composition of essential oil portion of unani formulation kulzam

    Directory of Open Access Journals (Sweden)

    K Ashok Kumar

    2011-01-01

    Full Text Available Kulzam is a popular unani, liquid formulation; indicated for several minor ailments like cough, cold, running nose, sore throat, insect bites, earache, tooth ache, etc. by the manufacturer. However, this over the counter formulation has not been scientifically evaluated for its claimed uses. Hence in the present study an attempt has been to check the chemical composition, antibacterial and antifungal activity as most of the above-mentioned conditions are underpinned by microbial activity. The antibacterial and antifungal activity of the formulation was carried out on human pathogenic bacteria Pseudomonas aerogenousa, Escherichia coli, Staphylococcus aureus, Corynebacterium and fungi Candida albicans, Aspergillus fumigates and was compared with standards ciprofloxacin and clotrimazole. Kulzam exhibited strong in vitro inhibition of growth against all the test micro-organisms at both 100 and 150 μl levels of undiluted formulation (test sample and more than that of standard at 150 μl level. The chemical composition of essential oil of the formulation was determined by gas chromatography−mass spectroscopy (GC-MS analysis. Thirteen compounds constituting about 93.56% of the essential oil were identified. The main components were Camphor, menthol, thymol, 2-propenal 3-phenyl-, eugenol, trans-caryophyllene, p-allylanisole, linalool, eucalyptol, l-limonene, 1-methyl-2-isopropylbenzene, and 1S-alpha-pinene. The outcome of this study shows that kulzam contain terpenes and their oxygenated derivatives, which are believed to be highly effective antibacterial, antifungal, analgesic, anti-inflammatory, antioxidant, spasmolytic and immunomodulatory agents. The formulation has been found to possess strong antibacterial and antifungal properties, and it becomes very difficult to pin point the specific compound responsible for studied activities. However, the study positively motivates the use of kulzam for common ailments.

  15. The effect of Ultrafine process on the Dissolution, Antibacterial activity, and Cytotoxicity of Coptidis rhizoma

    Directory of Open Access Journals (Sweden)

    Zhen-Yu Jiang

    2016-01-01

    Full Text Available Background: The dosage of herb ultrafine particle (UFP depended on the increased level of its dissolution, toxicity, and efficacy. Objective: The dissolution, antibacterial activity, and cytotoxicity of Coptidis rhizoma (CR UFP were compared with those of traditional decoction (TD. Materials and Methods: The dissolution of berberine (BBR of CR TD and UFP was determined by high-performance liquid chromatography. The antibacterial activity of CR extract was assayed by plate-hole diffusion and broth dilution method; the inhibitory effect of rat serums against bacteria growth was evaluated after orally given CR UFP or TD extract. The cytotoxicity of CR extract was evaluated by 3-(4,5-dimethylthiazol-2-Yl-2,5-diphenyltetrazolium bromide assay. Results: The dissolution amount of BBR from CR UFP increased 6-8-folds in comparison to TD at 2 min, the accumulative amount of BBR in both UFP and TD group increased in a time-dependent manner. The minimal inhibitory concentrations and minimal bactericidal concentrations of CR UFP extract decreased to 1/2~1/4 of those of TD extract. The inhibitory effect of rat serums against bacteria growth decreased time-dependently, and no statistical difference was observed between two groups at each time point. The 50% cytotoxic concentrations of UFP extract increased 1.66~1.97 fold than those of TD. Conclusions: The antibacterial activity and cytotoxicity of CR UFP increased in a dissolution-effect manner in vitro, the increased level of cytotoxicity was lower than that of antibacterial activity, and the inhibitory effect of rat serums containing drugs of UFP group did not improve.

  16. Larvicidal activity of synthetic disinfectants and antibacterial soaps against mosquito, Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Xue, Rui-De; Qualls, Whitney A

    2013-01-01

    Seven commercial synthetic disinfectant and antibacterial soap products were evaluated as mosquito larvicides against Culex quinquefasciatus Say in the laboratory. Three aerosol disinfectant products, at 0.01% concentration resulted in 58-76% mortality of laboratory-reared fourth instar mosquito larvae at 24 h posttreatment. Four antibacterial soap products at 0.0001% concentration resulted in 88-100% larval mortality at 24 h posttreatment. The active ingredient of the antibacterial soap products, triclosan (0.1%) resulted in 74% larval mortality. One of the antibacterial soap products, Equate caused the highest mosquito larval mortality in the laboratory. Equate antibacterial soap at the application rate of 0.000053 ppm resulted in 90% mortality of the introduced fourth instar larvae of Cx. quinquesfasicatus in the outdoor pools. In laboratory and field bioassays, the antibacterial soap resulted in significant larval mosquito mortality.

  17. Antibacterial and antifungal activity of a soda-lime glass containing copper nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Esteban-Tejeda, L; Pecharroman, C; Moya, J S [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Ines de la Cruz 3, Cantoblanco, Madrid 28049 (Spain); Malpartida, F [Centro Nacional de Biotecnologia, CSIC, Darwin 3, Cantoblanco, Madrid 28049 (Spain); Esteban-Cubillo, A, E-mail: jsmoya@icmm.csic.es [Tolsa S A R and D Department, Camino de Vallecas-Mejorada del Campo Km 1.6, 28031 Madrid (Spain)

    2009-12-16

    A low melting point soda-lime glass powder containing copper nanoparticles with high antibacterial (against gram-positive and gram-negative bacteria) and antifungal activity has been obtained. Sepiolite fibres containing monodispersed copper nanoparticles (d{sub 50}{approx}30 {+-} 5 nm) were used as the source of the copper nanoparticles. The observed high activity of the obtained glass powder, particularly against yeast, has been explained by considering the inhibitory synergistic effect of the Ca{sup 2+} lixiviated from the glass on the growth of the colonies.

  18. Antibacterial Activity of Electrochemically Synthesized Colloidal Silver Nanoparticles Against Hospital-Acquired Infections

    Science.gov (United States)

    Thuc, Dao Tri; Huy, Tran Quang; Hoang, Luc Huy; Hoang, Tran Huy; Le, Anh-Tuan; Anh, Dang Duc

    2017-06-01

    This study evaluated the antibacterial activity of electrochemically synthesized colloidal silver nanoparticles (AgNPs) against hospital-acquired infections. Colloidal AgNPs were synthesized via a single process using bulk silver bars, bi-distilled water, trisodium citrate, and direct current voltage at room temperature. Colloidal AgNPs were characterized by transmission electron microscopy, field-emission scanning electron microscopy, and energy-dispersive x-ray analyses. The antibacterial activity of colloidal AgNPs against four bacterial strains isolated from clinical samples, including methicillin-resistant Staphylococcus aureus, Escherichia coli O157:H7, multidrug-resistant Pseudomonas aeruginosa, and carbapenem-resistant Klebsiella pneumonia, was evaluated by disc diffusion, minimum inhibitory concentration (MIC), and ultrathin sectioning electron microscopy. The results showed that the prepared AgNPs were 19.7 ± 4.3 nm in size, quasi-spherical, and of high purity. Zones of inhibition approximately 6-10 mm in diameter were found, corresponding to AgNPs concentrations of 50 μg/mL to 100 μg/mL. The MIC results revealed that the antibacterial activity of the prepared AgNPs was strongly dependent on the concentration and strain of the tested bacteria.

  19. The antibacterial activities of aditoprim and its efficacy in the treatment of swine streptococcosis

    Science.gov (United States)

    Cheng, Guyue; Xu, Yamei; Zhu, Xudong; Xie, Shuyu; Wang, Liye; Huang, Lingli; Hao, Haihong; Liu, Zhenli; Pan, Yuanhu; Chen, Dongmei; Wang, Yulian; Yuan, Zonghui

    2017-01-01

    Aditoprim (ADP) has potential use as an antimicrobial agent in animals. However, its pharmacodynamic properties have not been systematically studied yet. In this study, the in vitro antibacterial activities of ADP and its main metabolites were assayed, and the in vivo antibacterial efficacy of ADP for the treatment of swine streptococcosis was evaluated. It was shown that Salmonella and Streptococcus from swine, Escherichia coli and Salmonella from chickens, E. coli, Streptococcus, Mannheimia, Pasteurella from calves, Streptococcus and Mannheimia from sheep, and E. coli, Flavobacterium columnare, Acinetobacter baumannii and Yersinia ruckeri from fishes were highly susceptible to ADP. Haemophilus parasuis from swine, Staphylococcus aureus, Aeromonas punctate, Mycobacterium tuberculosis, Streptococcus agalactiae from fishes, and Klebsiella from calves and sheep showed moderate susceptibility to ADP, whereas E. coli, Actinobacillus pleuropneumonia, Pasteurella, S. aureus, Clostridium perfringens from swine, S. aureus, C. perfringens from chickens, and S. aureus from calves were resistant to ADP. The main metabolites of ADP showed equal activity to that of their parent compound, and the prevention and therapeutic dosages of ADP recommended for swine streptococcosis were 10 and 20~40 mg/kg b.w., respectively. This study firstly showed that ADP had strong antibacterial activity and had potential to be used as a single drug in the treatment of bacterial infectious diseases. PMID:28145487

  20. Antibacterial Activity of Electrochemically Synthesized Colloidal Silver Nanoparticles Against Hospital-Acquired Infections

    Science.gov (United States)

    Thuc, Dao Tri; Huy, Tran Quang; Hoang, Luc Huy; Hoang, Tran Huy; Le, Anh-Tuan; Anh, Dang Duc

    2017-02-01

    This study evaluated the antibacterial activity of electrochemically synthesized colloidal silver nanoparticles (AgNPs) against hospital-acquired infections. Colloidal AgNPs were synthesized via a single process using bulk silver bars, bi-distilled water, trisodium citrate, and direct current voltage at room temperature. Colloidal AgNPs were characterized by transmission electron microscopy, field-emission scanning electron microscopy, and energy-dispersive x-ray analyses. The antibacterial activity of colloidal AgNPs against four bacterial strains isolated from clinical samples, including methicillin-resistant Staphylococcus aureus, Escherichia coli O157:H7, multidrug-resistant Pseudomonas aeruginosa, and carbapenem-resistant Klebsiella pneumonia, was evaluated by disc diffusion, minimum inhibitory concentration (MIC), and ultrathin sectioning electron microscopy. The results showed that the prepared AgNPs were 19.7 ± 4.3 nm in size, quasi-spherical, and of high purity. Zones of inhibition approximately 6-10 mm in diameter were found, corresponding to AgNPs concentrations of 50 μg/mL to 100 μg/mL. The MIC results revealed that the antibacterial activity of the prepared AgNPs was strongly dependent on the concentration and strain of the tested bacteria.

  1. PREPARATION AND THEIR ANTIBACTERIAL ACTIVITY OF ACTIVATED CARBON FIBER CONTAINING SILVER

    Institute of Scientific and Technical Information of China (English)

    CHENShuixia; LUOYing; 等

    2000-01-01

    Several kinds of activated carbon fiber(ACF),Granule Activated carbon(AC) containing silver ion or fine silver particle(Ag-ACF/AC) have been prepared by soaking ACF or AC in the salt solution of silver.Ag,AgCl and AgI compounds have been loaded onto the fibers:The stucture of the fibers was measured by scanning electron microscopy(SEM) and power X-ray diffraction(XRD),THe Ag content in the fiber was obtained by an Atomic absorption spectroscopy(AAS),The Ag+ content in water after the antibacterial test was measured by an Inductively Coupled plasma(ICP) emission spectroscopy.Antibacterial test was carried out against Escherichia coli(E.coli) and Staphylococcus aureus(S.aureus).The results show that Ag-ACF/AC have strong antibacterial activity against E.Coli and S.aureus.After dealt with ACF/AC loading Ag,AgCl,AgI,no E.coli and S.aureus alive in solution can be detected.The analysis of Agcontent in water after antibacterial test showed that the content of Ag meet the quality requirement of the National Potable Water Standrd,It is indicated that ACF/AC-Ag in this experiment would be a safe antibacterial agent.

  2. Preparation and characterization of HMSPP/MMT/silver nanocomposite films with antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Oliani, Washington Luiz; Komatsu, Luiz Gustavo Hiroki; Berenguer, Isabelle; Lugao, Ademar Benevolo; Parra, Duclerc Fernandes, E-mail: washoliani@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Lincopan, Nilton [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Escola de Farmacia. Dept. de Analises Clinicas; Rangari, Vijaya Kumar [Center For Advanced Materials Science and Engineering Tuskegee University, AL (United States)

    2015-07-01

    The aim of study was to use nanocomposites for bactericide packing for food. The polypropylene modified by irradiation in acetylene at dose of 12.5 kGy, also known as high-melt-strength-polypropylene (HMSPP), with montmorillonite (MMT) and silver nanoparticles (AgNPs) composed a mix to process by melt intercalation in a twin-screw extruder. As compatibilizer agent it has been used a propylene graft maleic anhydride copolymer (PP-g-MA). The nanocomposites were evaluated by Fourier Transformed Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX) and determination of antibacterial activity. The results indicate the formation of microstructures predominantly intercalated and flocculated. Further, the antibacterial properties of the films were investigated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. (author)

  3. Six new physalins from Physalis alkekengi var. franchetii and their cytotoxicity and antibacterial activity.

    Science.gov (United States)

    Yang, Ye-Kun; Xie, Si-da; Xu, Wan-Xuan; Nian, Yin; Liu, Xiao-Ling; Peng, Xing-Rong; Ding, Zhong-Tao; Qiu, Ming-Hua

    2016-07-01

    Six new physalin steroids, 7β-methoxylisophysalin B (1), 7β-methoxylphysalin C (2), physalin V (3), physalin VI (4), physalin VII (5), isophysalin I (6), together with 20 known physalins (7-26) were isolated from calyces of Physalis alkekengi var. franchetii. Structures of the new compounds were revealed through 1D and 2D NMR and mass spectroscopic methods. Compounds 1-26 were evaluated for cytotoxicity against human HL-60, SMMC-7721, A-549, MCF-7 and SW-480, and the results indicated that compounds 8, 11, and 14 displayed potent cytotoxicities (IC50<5μM) in vitro. Further antibacterial assay indicated that compounds 8, 14, and 19 showed high antibacterial activities against Bacillus subtilis and Escherichia coli.

  4. Antibacterial activity of single crystalline silver-doped anatase TiO2 nanowire arrays

    Science.gov (United States)

    Zhang, Xiangyu; Li, Meng; He, Xiaojing; Hang, Ruiqiang; Huang, Xiaobo; Wang, Yueyue; Yao, Xiaohong; Tang, Bin

    2016-05-01

    Well-ordered, one-dimensional silver-doped anatase TiO2 nanowire (AgNW) arrays have been prepared through a hydrothermal growth process on the sputtering-deposited AgTi layers. Electron microscope analyses reveal that the as-synthesized AgNW arrays exhibit a single crystalline phase with highly uniform morphologies, diameters ranging from 85 to 95 nm, and lengths of about 11 μm. Silver is found to be doped into TiO2 nanowire evenly and mainly exists in the zerovalent state. The AgNW arrays show excellent efficient antibacterial activity against Escherichia coli (E. coli), and all of the bacteria can be killed within 1 h. Additionally, the AgNW arrays can still kill E. coli after immersion for 60 days, suggesting the long-term antibacterial property. The technique reported here is environmental friendly for formation of silver-containing nanostructure without using any toxic organic solvents.

  5. Coumarins and flavonoid from Murraya paniculata (L.) Jack: Antibacterial and anti-inflammation activity.

    Science.gov (United States)

    Rodanant, Pirasut; Khetkam, Pichit; Suksamrarn, Apichart; Kuvatanasuchati, Jintakorn

    2015-11-01

    The ethyl acetate extract of leaves of Murraya paniculata (L.) Jack was described in the previous in vitro study on the inhibition effect on the growth of periodontopathic bacteria and the reduction of cytokines from LPS-stimulated macrophages. In this study, four coumarins including murrangatin (1), murrangatin acetate (2), murranganonesenecionate (3), micropubescin (4) and one flavonoid, 3', 4', 5', 7-tetramethoxyflavone (5) were isolated from the leaves of ethyl acetate extract of M. paniculata. MTT assay was used to test cytotoxicity on human gingival fibroblast and monocytes. The isolated compounds were evaluated for their antibacterial effect against Porphyromonas gingivalis (ATCC33277) and anti-inflammation on lipopolysaccharide-stimulated inflammation using monocyte cells. All isolated compounds exhibited antibacterial activity against P. gingivalis (ATCC 33277). Murranganonesenecionate (3) was highly potent anti-inflammation properties. The coumarin constituents from M. paniculata leaves might be potential lead molecules for the development of antimicrobial drugs for treating periodontal disease.

  6. EFFECTS OF COPPER ION IMPLANTATION ON ANTIBACTERIAL ACTIVITY OF AISI420 STAINLESS STEEL

    Institute of Scientific and Technical Information of China (English)

    Z.G. Dan; H.W. Ni; B.F. Xu; J. Xiong; P. Y. Xiong

    2005-01-01

    Antibacterial activity of AISI420 stainless steel (SS) implanted by copper was investigated. Ions extracted from a metal vapor vacuum arc (MEVVA) are sourced with 100keV energy and a dose range from 0.2×1017 to 2.0×1017ions .cm-2. The saturation dose of Cu implantation in AISI420 SS and Cu surface concentration were calculated at the energy of 100keV. The effect of dose on the antibacterial activity was analyzed. Results of antibacterial test show that the saturation dose is the optimum implantation dose for best antibacterial activity, which is above 99% against both Escherichia coli and Staphylococcus aureus. Novel phases such as Fe4Cu3 and Cu9.9Fe0.1 were found in the implanted layer by glancing angle X-ray diffraction (GXRD). The antibacterial activity of AISI420 SS attributes to Cu-contained phase.

  7. A Study on Antibacterial Activity and Chemical Composition of the Petroleum Ether Extract from Aspergillusniger Mycelia

    Institute of Scientific and Technical Information of China (English)

    Yang; XIAO; Wujuan; LIU; Zhu; LI

    2014-01-01

    In order to develop natural antibacterial agents,the antibacterial activity of Aspergillusnigerxj was investigated.After being cultured in potato dextrose liquid medium liquid medium,mycelia was under heating reflux extraction with 90% ethanol.Removal of ethanol under reduced pressure gave a residue,to which water was added and then extracted with petroleum ether and ethyl acetate.In vacuo evaporation of the solvents yielded three crude extracts.Then the disc diffusion method was used to measure the antibacterial activity of these extracts.The petroleum ether extract with antibacterial activity was separated by silica gel column chromatography method,then separated and identified by GC-MS after been methyl esterified.At the concentration of 50 mg /mL,the petroleum ether extract of mycelia exhibited inhibitory effect against Staphylococcus aureus.The petroleum ether extract from Aspergillusnigerxj mycelia contained natural substances with antibacterial activity and fatty acids are the main constituents in it.

  8. Isolation and Identification of a Rare Actinomycete with Antibacterial Activity from Saline Region of Iran

    Directory of Open Access Journals (Sweden)

    Samaneh Mashhadi

    2016-07-01

    Full Text Available Background: The appearance of multi-drug resistant microorganisms is becoming a global problem. Already several strategies have been employed to overcome antibiotic resistance issue. Developing new antimicrobial compounds from microbial sources could be a beneficial solution. Hence screening programs in order to discover new antibiotics from microbial entities are interesting. Because of high capabilities of extremophiles for adaptation to harsh environmental conditions, the microbial communities of the extreme environments could be regarded as rich resources for new antibacterial metabolites. Materials and Methods: In this research different saline environments of Iran have been subjected to screening of antibiotic producing actinomycetes using overlaid method after the ingredient optimization of culture media. The strain which was shown pronounce inhibition zone in the screening step, has been phylogenetically analyzed followed by studying the effect of agar concentration and cultivation time on the production of antibacterial agent(s. Results: The strain RS1, a rare actinomycete, had antibacterial activity against Escherichia coli (PTCC 1330 and Bacillus subtilis (PTCC 1023 and taxonomically belongs to the genus Amycolatopsis with high similarity of 99.6% to Amycolatopsis coloradensis IMSNU 22096T based on sequencing of 16S rRNA gene nucleotide. The zone of growth inhibition of E.coli was the widest when the base layer had contained 1.2% agar, while no significant differences were observed on anti-gram-positive bacterial assay. This strain produced the antibacterial agent at the highest level after 5 days when B. subtilis was used as an indicator, but the production of antibacterial agent active against E.Coli was reached to its highest level on the 3rd days of cultivation and then was decreased significantly. Conclusion: Due to the results of agar concentration and time course study as well as possessing activity against both Gram

  9. Antibacterial Activity of Propolis Ethanol Extract against Antibiotic Resistance

    Directory of Open Access Journals (Sweden)

    Maryam Mohammadi-Sichani

    2014-03-01

    Full Text Available Background: Burn wound is a suitable site for incidence of resistant infections; thus, the research for finding effective drugs against this infection is necessary. The purpose of this study was to determine antibacterial activity of Isfahan bee propolis extracts against beta-lactamase producing bacteria isolated from burn wound infections. Materials and Methods: Ethanol extract of Isfahan bee propolis was prepared by 28 g of propolis in 100 ml of 70% ethanol. Antibacterial activity of ethanol extracts were evaluated against beta-lactamase producing bacteria (Staphylococcus aureus and Pseudomonas aeruginosa isolated of burn wound infection by well diffusion method. Broth serial dilution method was used to determine MBC of extract. Beta-lactamase production of isolates was detected by iodometric test, imipenem-EDTA combined disk test and imipenem-EDTA double-disk synergy test. Results: Ethanol extract of propolis was found to be the most effective against S. aureus strains (inhibition zone=17.66±0.47 mm than P. aeruginosa strains (inhibition zone=7 mm. The MIC and MBC values of the extracts against S. aureus strains were 0.0143 and 0.0286 mg/ml and these values against P. aeruginosa strains were 0.75 and 1.5 mg/ml, respectively. Among the S. aureus clinical isolates, all of strains produced beta-lactamase. Imipenem-EDTA double-disk synergy test showed that only one clinical isolate of P. aeruginosa was metallo-beta-lactamase positive. Conclusion: This study demonstrated that ethanol extract of Isfahan bee propolis is mainly active against S. aureus and it is effective on P. aeruginosa at higher concentration. Ethanol extract of propolis did not inhibit production of beta-lactamase enzyme in tested bacteria.

  10. PRELIMINARY PHYTOCHEMICAL, ANTI-BACTERIAL, ANALGESIC, ANTI-DIARRHOEAL AND CYTOTOXIC ACTIVITY OF METHANOLIC EXTRACT OF POLYALTHIA SUBEROSA LEAVES

    Directory of Open Access Journals (Sweden)

    S.M. Moazzem Hossen et al.

    2012-05-01

    Full Text Available The MeOH extract of leaves of Polyalthia suberosa Roxb. (Annonaceae was screened for its antibacterial, analgesic, Antidiarrhoeal and cytotoxic activities. The extract showed moderate anti-bacterial activity against Vibrio cholerae, Sheigella sonnei, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus saprophyticus. It also produced significant (P<0.01 writhing inhibition in acetic acid induced writhing in mice at dose of 250 and 500 mg/kg, which was comparable to the standard drug diclofenac sodium. Moreover, when tested for its antidiarrhoeal effects on castor oil induced diarrhea in mice, it decreased the frequency of defecation and increased mean latent period significantly (P<0.01 at the dose of 500 mg/kg comparable to the standard drug loperamide. The extract also exhibited high level of cytotoxicity in brine shrimp lethality bioassay (LC50: 30 µg/ml. The overall results tend to suggest the antibacterial, analgesic, antidiarrhoeal and cytotoxic activities of the extract.

  11. Metal ions, not metal-catalyzed oxidative stress, cause clay leachate antibacterial activity.

    Directory of Open Access Journals (Sweden)

    Caitlin C Otto

    Full Text Available Aqueous leachates prepared from natural antibacterial clays, arbitrarily designated CB-L, release metal ions into suspension, have a low pH (3.4-5, generate reactive oxygen species (ROS and H2O2, and have a high oxidation-reduction potential. To isolate the role of pH in the antibacterial activity of CB clay mixtures, we exposed three different strains of Escherichia coli O157:H7 to 10% clay suspensions. The clay suspension completely killed acid-sensitive and acid-tolerant E. coli O157:H7 strains, whereas incubation in a low-pH buffer resulted in a minimal decrease in viability, demonstrating that low pH alone does not mediate antibacterial activity. The prevailing hypothesis is that metal ions participate in redox cycling and produce ROS, leading to oxidative damage to macromolecules and resulting in cellular death. However, E. coli cells showed no increase in DNA or protein oxidative lesions and a slight increase in lipid peroxidation following exposure to the antibacterial leachate. Further, supplementation with numerous ROS scavengers eliminated lipid peroxidation, but did not rescue the cells from CB-L-mediated killing. In contrast, supplementing CB-L with EDTA, a broad-spectrum metal chelator, reduced killing. Finally, CB-L was equally lethal to cells in an anoxic environment as compared to the aerobic environment. Thus, ROS were not required for lethal activity and did not contribute to toxicity of CB-L. We conclude that clay-mediated killing was not due to oxidative damage, but rather, was due to toxicity associated directly with released metal ions.

  12. Antibacterial activity of Bixa orellana L. (achiote) against Streptococcus mutans and Streptococcus sanguinis

    Institute of Scientific and Technical Information of China (English)

    Dyanne Medina-Flores; Gabriela Ulloa-Urizar; Rosella Camere-Colarossi; Stefany Caballero-Garca; Frank Mayta-Tovalino; Juana del Valle-Mendoza

    2016-01-01

    Objective: To evaluate the cytotoxic and antibacterial effect of Bixa orellana L. (B. orellana) (achiote) methanol extract against Streptococcus mutans (ATCC 25175) (S. mutans) and Streptococcus sanguinis (ATCC 10556) (S. sanguinis). Methods: Two methanol extracts of B. orellana were prepared in vitro, from the seeds and leaves. The antibacterial activity of extracts against S. mutans and S. sanguinis was evaluated using the cup-plate agar diffusion method. The minimum inhibitory concen-tration (MIC) was determined using the microdilution method and the cytotoxic activity was determinated by using the cell line MDCK. Results: A stronger antibacterial effect was observed with the leaves methanolic extract with an inhibition zone of (19.97 ± 1.31) mm against S. mutans and (19.97 ± 1.26) mm against S. sanguinis. The methanolic extract of the seeds had an activity of (15.11 ± 1.03) mm and (16.15 ± 2.15) mm against S. mutans and S. sanguinis, respectively. The MIC of the leaf and the seed extracts against S. sanguinis was 62.5 and 125 mg/mL, respectively, and the MIC of the leaf extract against S. mutans was 62.5 mg/mL, and for the seed extract it was 31.25 mg/mL. The 50%cytotoxic concentration was 366.45 and 325.05 mg/mL for the leaves and seeds extracts, respectively. Conclusions: The experimental findings demonstrated the antibacterial effect of the methanolic extract of B. orellana (achiote) on S. mutans and S. sanguinis. The extract of this plant is cytotoxic at high concentrations.

  13. Antibacterial activity of Bixa orellana L.(achiote) against Streptococcus mutans and Streptococcus sanguinis

    Institute of Scientific and Technical Information of China (English)

    Dyanne Medina-Flores; Gabriela Ulloa-Urizar; Rosella Camere-Colarossi; Stefany Caballero-García; Frank Mayta-Tovalino; Juana del Valle-Mendoza

    2016-01-01

    Objective: To evaluate the cytotoxic and antibacterial effect of Bixa orellana L.(B. orellana)(achiote) methanol extract against Streptococcus mutans(ATCC 25175)(S. mutans) and Streptococcus sanguinis(ATCC 10556)(S. sanguinis).Methods: Two methanol extracts of B. orellana were prepared in vitro, from the seeds and leaves. The antibacterial activity of extracts against S. mutans and S. sanguinis was evaluated using the cup-plate agar diffusion method. The minimum inhibitory concentration(MIC) was determined using the microdilution method and the cytotoxic activity was determinated by using the cell line MDCK.Results: A stronger antibacterial effect was observed with the leaves methanolic extract with an inhibition zone of(19.97 ± 1.31) mm against S. mutans and(19.97 ± 1.26) mm against S. sanguinis. The methanolic extract of the seeds had an activity of(15.11 ± 1.03)mm and(16.15 ± 2.15) mm against S. mutans and S. sanguinis, respectively. The MIC of the leaf and the seed extracts against S. sanguinis was 62.5 and 125 mg/m L, respectively,and the MIC of the leaf extract against S. mutans was 62.5 mg/m L, and for the seed extract it was 31.25 mg/m L. The 50% cytotoxic concentration was 366.45 and 325.05 mg/m L for the leaves and seeds extracts, respectively.Conclusions: The experimental findings demonstrated the antibacterial effect of the methanolic extract of B. orellana(achiote) on S. mutans and S. sanguinis. The extract of this plant is cytotoxic at high concentrations.

  14. Regenerable Antibacterial Cotton Fabric by Plasma Treatment with Dimethylhydantoin: Antibacterial Activity against S. aureus

    Directory of Open Access Journals (Sweden)

    Chang-E. Zhou

    2017-01-01

    Full Text Available This study examined the influence of variables in a finishing process for making cotton fabric with regenerable antibacterial properties against Staphylococcus aureus (S. aureus. 5,5-dimethylhydantoin (DMH was coated onto cotton fabric by a pad-dry-plasma-cure method. Sodium hypochlorite was used for chlorinating the DMH coated fabric in order to introduce antibacterial properties. An orthogonal array testing strategy (OATS was used in the finishing process for finding the optimum treatment conditions. After finishing, UV-Visible spectroscopy, Scanning Electron Microscopy (SEM, and Fourier Transform Infrared Spectroscopy (FTIR were employed to characterise the properties of the treated cotton fabric, including the concentration of chlorine, morphological properties, and functional groups. The results show that cotton fabric coated with DMH followed by plasma treatment and chlorination can inhibit S. aureus and that the antibacterial property is regenerable.

  15. Active Radiation Level Measurement on New Laboratory Instrument for Evaluating the Antibacterial Activity of Radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Joh, Eunha; Park, Jang Guen [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A disc method has been widely used to measure the antibacterial effect of chemical agents. However, it is difficult to measure the antibacterial effect of radioisotopes using a disc method. A disc method is a method for diffusing a drug by placing the drug containing disc on the medium. In this method, radioisotopes are diffused on the medium and it is difficult to measure the exact effect by radiation. Thus, new laboratory equipment needs to evaluate the antibacterial activity by the radioisotopes. In this study, we measured the radiation level of radioisotopes on a new laboratory instrument using a MCNP. A disc method has been widely used to measure the antibacterial effect of chemical agents. This method uses a drug diffusion system for the measurement of anti-bacterial antibiotics. To measure the antimicrobial activity of a radioisotope, a new type of laboratory instrument is necessary to prevent the drug from spreading. The radioisotopes are used to diagnose and treat cancer. However, studies for anti-biotical use have not progressed. The radiation of radioisotopes has the effect of killing bacteria. Before this study proceeds further, it is necessary to be able to measure the antimicrobial activity of the radioisotope easily in the laboratory. However, in this study, it was possible to measure the antimicrobial activity of the radioisotope in the laboratory using a new laboratory instrument. We intend to start evaluation studies of the antibacterial activity of specific radioisotopes. In addition, it will be possible to develop research to overcome diseases caused by bacteria in the future.

  16. Synergistic antibacterial activity of Curcumin with antibiotics against Staphylococcus aureus.

    Science.gov (United States)

    Teow, Sin-Yeang; Ali, Syed Atif

    2015-11-01

    This study evaluated the synergistic antibacterial activity of Curcumin with 8 different antibiotic groups. Two reference, one clinical and ten environmental strains of Staphylococcus aureus (S. aureus) were tested. Disc diffusion assay with 25 μg/mL Curcumin demonstrated synergism in combination with a majority of tested antibiotics against S. aureus. However, checkerboard micro dilution assay only showed synergism, fractional inhibitory concentration index (FICI) indifferent interactions but no antagonism was observed. In time-kill curve, appreciable reduction of bacterial cells was also observed in combination therapy (Curcumin + antibiotics) compared to monotherapy (Curcumin or antibiotic(s) alone). The antibiotics with higher synergistic interaction with Curcumin are arranged in a decreasing order: Amikacin > Gentamicin > Ciprofloxacin.

  17. Antibacterial activity of Ocimum gratissimum L. essential oil

    Directory of Open Access Journals (Sweden)

    Celso Vataru Nakamura

    1999-09-01

    Full Text Available The essential oil (EO of Ocimum gratissimum inhibited Staphylococcus aureus at a concentration of 0.75 mg/ml. The minimal inhibitory concentrations (MICs for Shigella flexineri, Salmonella enteritidis, Escherichia coli, Klebsiella sp., and Proteus mirabilis were at concentrations ranging from 3 to 12 mg/ml. The endpoint was not reached for Pseudomonas aeruginosa (>=24 mg/ml. The MICs of the reference drugs used in this study were similar to those presented in other reports. The minimum bactericidal concentration of EO was within a twofold dilution of the MIC for this organism. The compound that showed antibacterial activity in the EO of O. gratissimum was identified as eugenol and structural findings were further supported by gas chromatography/mass spectra retention time data. The structure was supported by spectroscopic methods.

  18. Synthesis, Characterization, and Antibacterial Activity of Cross-Linked Chitosan-Glutaraldehyde

    Directory of Open Access Journals (Sweden)

    Long-Biao Guo

    2013-05-01

    Full Text Available This present study deals with synthesis, characterization and antibacterial activity of cross-linked chitosan-glutaraldehyde. Results from this study indicated that cross-linked chitosan-glutaraldehyde markedly inhibited the growth of antibiotic-resistant Burkholderia cepacia complex regardless of bacterial species and incubation time while bacterial growth was unaffected by solid chitosan. Furthermore, high temperature treated cross-linked chitosan-glutaraldehyde showed strong antibacterial activity against the selected strain 0901 although the inhibitory effects varied with different temperatures. In addition, physical-chemical and structural characterization revealed that the cross-linking of chitosan with glutaraldehyde resulted in a rougher surface morphology, a characteristic Fourier transform infrared (FTIR band at 1559 cm−1, a specific X-ray diffraction peak centered at 2θ = 15°, a lower contents of carbon, hydrogen and nitrogen, and a higher stability of glucose units compared to chitosan based on scanning electron microscopic observation, FTIR spectra, X-ray diffraction pattern, as well as elemental and thermo gravimetric analysis. Overall, this study indicated that cross-linked chitosan-glutaraldehyde is promising to be developed as a new antibacterial drug.

  19. Superior antibacterial activity of GlcN-AuNP-GO by ultraviolet irradiation.

    Science.gov (United States)

    Govindaraju, Saravanan; Samal, Monica; Yun, Kyusik

    2016-12-01

    A complete bacterialysis analysis of glucosamine-gold nanoparticle-graphene oxide (GlcN-AuNP-GO) and UV-irradiated GlcN-AuNP-GO was conducted. Analytical characterization of GlcN-AuNPs, GO and GlcN-AuNP-GO revealed UV-Vis absorbance peak at around 230 and 500nm. Microscopic characterization of prepared nanomaterials was performed by scanning electron microscope, atomic force microscopy, and high-resolution transmission microscopy. The results confirmed that the GlcN-AuNPs were uniformly decorated on the surface and edges of graphene sheets. In addition, potent antibacterial activity of GlcN-AuNP-GO that was UV irradiated for 10min and normal GlcN-AuNP-GO was detected, compared to the standard drug kanamycin, against both Gram-negative and positive bacteria. The minimum inhibitory concentration (MIC) and fluorescence intensity spectra results for Escherichia coli and Enterococcus faecalis showed that the UV-irradiated GlcN-AuNP-GO has better antibacterial activity than normal GlcN-AuNP-GO and kanamycin. Morphological changes were detected by AFM after treatment. These results confirmed that GlcN-AuNP-GO is a potent antibacterial agent with good potential for use in manufacturing medical instruments, pharmaceutical industries and in waste water treatment. Copyright © 2016. Published by Elsevier B.V.

  20. Electrodeposition, characterization, and antibacterial activity of zinc/silver particle composite coatings

    Energy Technology Data Exchange (ETDEWEB)

    Reyes-Vidal, Y.; Suarez-Rojas, R.; Ruiz, C.; Torres, J. [Center of Research and Technological Development in Electrochemistry (CIDETEQ), Parque Tecnológico Sanfandila, Pedro Escobedo, Querétaro, A.P.064, C.P.76703, Querétaro (Mexico); Ţălu, Ştefan [Technical University of Cluj-Napoca, Faculty of Mechanical Engineering, Department of AET, Discipline of Descriptive Geometry and Engineering Graphics, 103-105 B-dul Muncii St., Cluj-Napoca 400641 Cluj (Romania); Méndez, Alia [Centro de Química-ICUAP Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria Puebla, 72530 Puebla (Mexico); Trejo, G., E-mail: gtrejo@cideteq.mx [Center of Research and Technological Development in Electrochemistry (CIDETEQ), Parque Tecnológico Sanfandila, Pedro Escobedo, Querétaro, A.P.064, C.P.76703, Querétaro (Mexico)

    2015-07-01

    Highlights: • Zn/AgPs composites coatings were formed for electrodeposition. • CTAB promotes occlusion of silver particles in the coating. • Zn/AgPs coatings present very good antibacterial activity. - Abstract: Composite coatings consisting of zinc and silver particles (Zn/AgPs) with antibacterial activity were prepared using an electrodeposition technique. The morphology, composition, and structure of the Zn/AgPs composite coatings were analyzed using scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS), inductively coupled plasma (ICP) spectrometry, and X-ray diffraction (XRD). The antibacterial properties of the coatings against the microorganisms Escherichia coli as a model Gram-negative bacterium and Staphylococcus aureus as a model Gram-positive bacterium were studied quantitatively and qualitatively. The results revealed that the dispersant cetyltrimethylammonium bromide (CTAB) assisted in the formation of a stable suspension of Ag particles in the electrolytic bath for 24 h. Likewise, a high concentration of CTAB in the electrolytic bath promoted an increase in the number of Ag particles occluded in the Zn/AgPs coatings. The Zn/AgPs coatings that were obtained were compact, smooth, and shiny materials. Antimicrobial tests performed on the Zn/AgPs coatings revealed that the inhibition of bacterial growth after 30 min of contact time was between 91% and 98% when the AgPs content ranged from 4.3 to 14.0 mg cm{sup −3}.

  1. Strategy for introducing antibacterial activity under ambient illumination in titania nanoparticles

    Science.gov (United States)

    Hsu, Alexander; Liu, Fangzhou; Leung, Yu Hang; Ma, Angel P. Y.; Djurišić, Aleksandra B.; Leung, Frederick C. C.

    2014-03-01

    Titanium dioxide (TiO2) is a wide bandgap (~3.4 eV) semiconductor material which is commonly used as a photocatalyst and antibacterial material. UV illumination with energy similar to the bandgap is often needed to make the material active. It would be favorable for practical applications, if its action can also be activated under ambient. Recently, robust antibacterial action was demonstrated on ZnO nanoparticles under ambient illumination. In this study, we demonstrated robust antibacterial activity of TiO2 nanoparticles induced by annealing under ambient illumination. It was found that the antibacterial activity could be significantly changed by tuning the annealing temperatures and using different crucibles containing the nanoparticles. Bacterium Escherichia coli was used as the model organism in the test. It was observed that although no significant antibacterial activity was observed on the starting material (untreated commercial TiO2 nanoparticles), the activity increases significantly if the nanoparticles were annealed above 650 °C with crucible lined with copper foil. The survival rate of E. coli bacteria approaches to zero if the nanoparticles annealing temperature reaches 850 °C. Under optimized conditions, three different titania nanoparticle samples exhibited antibacterial activity under ambient illumination. This work sheds light on the development of ambient-active antibacterial coating and in particular, on the modification of any TiO2 material to become ambient-active with a suitable treatment.

  2. Enhanced antibacterial activity of lysozyme immobilized on chitin nanowhiskers.

    Science.gov (United States)

    Jiang, Suisui; Qin, Yang; Yang, Jie; Li, Man; Xiong, Liu; Sun, Qingjie

    2017-04-15

    In this paper, the contribution of chitin nanowhiskers (CHNW) to the enzymatic activity and antimicrobial activity of lysozyme adsorbed on CHNW was investigated. An activity assay showed that the lysozyme-CHNW system exhibited significant promotion potency on lysozyme activity, which was approximately 1.5-fold greater than that of free lysozyme. The molecular promotion mechanism of lysozyme immobilized by adsorption onto CHNW was investigated by ultraviolet-visible spectrophotometry, fluorescence spectroscopy, and circular dichroism spectroscopy. The results indicated that changes in the secondary structure of lysozyme adsorption onto CHNW resulted in superior enzymatic activity. Furthermore, the antimicrobial assays indicated that the antimicrobial activity of the lysozyme-CHNW system was greater than that of free lysozyme, whereas its antimicrobial effect on a gram-negative bacterium was better than that on gram-positive bacteria. This research provides a facile and promising approach for increasing the application of chitin-derived and enhancing the antibacterial efficiency on preservation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Antifungal and antibacterial activities of Petroselinum crispum essential oil.

    Science.gov (United States)

    Linde, G A; Gazim, Z C; Cardoso, B K; Jorge, L F; Tešević, V; Glamoćlija, J; Soković, M; Colauto, N B

    2016-07-29

    Parsley [Petroselinum crispum (Mill.) Fuss] is regarded as an aromatic, culinary, and medicinal plant and is used in the cosmetic, food, and pharmaceutical industries. However, few studies with conflicting results have been conducted on the antimicrobial activity of parsley essential oil. In addition, there have been no reports of essential oil obtained from parsley aerial parts, except seeds, as an alternative natural antimicrobial agent. Also, microorganism resistance is still a challenge for health and food production. Based on the demand for natural products to control microorganisms, and the re-evaluation of potential medicinal plants for controlling diseases, the objective of this study was to determine the chemical composition and antibacterial and antifungal activities of parsley essential oil against foodborne diseases and opportunistic pathogens. Seven bacteria and eight fungi were tested. The essential oil major compounds were apiol, myristicin, and b-phellandrene. Parsley essential oil had bacteriostatic activity against all tested bacteria, mainly Staphylococcus aureus, Listeria monocytogenes, and Salmonella enterica, at similar or lower concentrations than at least one of the controls, and bactericidal activity against all tested bacteria, mainly S. aureus, at similar or lower concentrations than at least one of the controls. This essential oil also had fungistatic activity against all tested fungi, mainly, Penicillium ochrochloron and Trichoderma viride, at lower concentrations than the ketoconazole control and fungicidal activity against all tested fungi at higher concentrations than the controls. Parsley is used in cooking and medicine, and its essential oil is an effective antimicrobial agent.

  4. Antibacterial and antifungal activities of some Mexican medicinal plants.

    Science.gov (United States)

    Ruiz-Bustos, E; Velazquez, C; Garibay-Escobar, A; García, Z; Plascencia-Jatomea, M; Cortez-Rocha, M O; Hernandez-Martínez, J; Robles-Zepeda, R E

    2009-12-01

    In Mexico about 4,000 plant species have some medicinal use. The aim of this work was to evaluate the antimicrobial activity of six Mexican medicinal plants against fungi and Gram-positive and Gram-negative bacteria. Methanolic extracts were prepared from the Mexican medicinal plants Amphypteringium adstrigens, Castella tortuosa, Coutarea latiflora, Ibervillea sonorae, Jatropha cuneata, and Selaginella lepidophylla. The antibacterial and antifungal activities of the plants were determined by the broth microdilution method and the radial growth inhibition assay, respectively. All Mexican plants tested showed antimicrobial activity. Among the six plant extracts analyzed, J. cuneata showed the highest growth-inhibitory activity against fungi, Gram-positive and Gram-negative bacteria (J. cuneata > A. adstrigens > C. latiflora > C. tortuosa > I. sonorae approximately S. lepidophylla). Shigella flexneri and Staphylococcus aureus were the most susceptible bacteria to plant extracts. Complete inhibition of S. flexneri growth was observed with J. cuneata methanolic extract at 90 microg/mL. This plant extract also showed the strongest antifungal activity against Fusarium verticillioides and Aspergillus niger. Our data suggest that the medicinal plants tested have important antimicrobial properties. This is the first report describing the antimicrobial activities of several of the Mexican medicinal plants used in this study.

  5. HIGH IMMOBILIZATION OF ANTIBACTERIAL MOIETIES ONTO MONODISPERSE MICROSPHERES BY DISPERSION POLYMERIZATION USING BICATIONIC VIOLOGEN SURFMER

    Institute of Scientific and Technical Information of China (English)

    Sheng-liu Wang; Xiao-fang Yang; Lian-ying Liu; Wan-tai Yang

    2012-01-01

    In order to achieve monodisperse particles with high content of antibacterial groups covalently bonded on surface,a bicationic viologen,N-hexyl-N'-(4-vinylbenzyl)-4,4'-bipyridinium bromide chloride (HVV) was devised as a surfmer in dispersion polymerization of styrene (St) using a mixture of methanol (or ethylene glycol) and water as media.Effects of content of HVV,its addition profile and composition of reaction media on particles size and incorporation of HVV moieties were mainly investigated.The attachment of silver and gold nanoparticles on particle surface under UV irradiation ascertained the surface-bonded HVV segments.SEM,TEM observations and XPS,zata potential measurements indicated that increase of initial HVV contents and addition of HVV (when polymerization had been performed for 3 h) led to grown particles and enhanced immobilization of HVV moieties.Using a mixture of ethylene glycol and water as reaction media,small particles (520-142 nm) with highly attached HVV moieties were prepared.Furthermore,antibacterial efficacy of the resultant particles against S.aureus was assayed,and particles with more HVV moieties anchored on surface demonstrated greater efficiency of antibacterial activity.

  6. Preparation and antibacterial activity of Ag–TiO2 composite film by liquid phase deposition (LPD) method

    Indian Academy of Sciences (India)

    S-Q Sun; B Sun; Wenqin Zhang; D Wang

    2008-02-01

    A liquid phase deposition (LPD) method has been devised for the deposition of Ag–TiO2 thin films on ceramic tiles with glazed surface at a low temperature. The Ag–TiO2 thin films obtained were welladhered, homogenous and coloured by interference of reflected light. The films were characterized by X-ray diffraction and scanning electron microscopy. From these analyses, it was found that silver ions were trapped in TiO2 matrix and their reduction could be achieved at 600°C annealing temperature. The antibacterial activity against S. aureus and . coli has been studied applying the so called antibacterial-drop test. The Ag–TiO2 thin films exhibited a high antibacterial activity. AAS was used for the quantitave determination of silver ion concentration releasing from the Ag–TiO2 thin film. The releasing rate of silver ions from the Ag–TiO2 film was 0.118 g/ml during 192 h. The antibacterial effect of Ag–TiO2 thin film before and after aging in a weathering chamber for 48 h was compared and the results show that the antibacterial activity is not compromised after weathering.

  7. Preparation and antibacterial activities of hollow silica-Ag spheres.

    Science.gov (United States)

    Lin, Lin; Zhang, Haifang; Cui, Haiying; Xu, Mingqiang; Cao, Shunsheng; Zheng, Guanghong; Dong, Mingdong

    2013-01-01

    Hollow silica spheres with round mesoporous shells were synthesized by core-shell template method, using monodispersed cationic polystyrene particles as core, and TEOS (tetraethoxysilane) as the silica source to form shell. After calcination at 550°C, uniform spheres with a thin shell of silica and hollow interior structures. Transmission electron microscopy results showed that the size of the spheres is about 700 nm in diameter with narrow distribution. In addition, the spheres have a high surface area of 183 m(2)/g. The spheres were subsequently used as silver-loading substrates and the silver loaded spheres were tested in antimicrobial study against gram negative bacteria Eschrichia coli in vitro. The hollow silica-Ag spheres proved significantly higher antibacterial efficacy against E. coli as compared to that of the common silica-Ag particles.

  8. Antioxidant and antibacterial activities of acetonitrile and hexane extracts of Lentinus tigrinus and Pleurotus djamour

    Science.gov (United States)

    This paper highlighted the antioxidant and antibacterial activities of Lentinus tigrinus and Pleurotus djamour. Extracts of mushroom fruiting bodies were obtained using hexane and acetonitrile solvents. Acetonitrile extracts of both mushrooms exhibited higher biological activities than hexane extrac...

  9. Antibacterial activities of PHU - AgNO{sub 3} nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Panzaru, Carmen; Danciu, M; Mihailovici, Maria-Sultana [' Gr.T.Popa' University of Medicine and Pharmacy, Iasi (Romania)], E-mail: carmenpanzaru@yahoo.com; Ciobanu, C [' Petru Poni' Institute of Macromolecular Chemistry, Iasi (Romania)

    2009-05-01

    Objective was to characterize the antibacterial action for six combination of PHU-AgNO{sub 3} synthesized in 'Petru Poni' Institute of Macromolecular Chemistry, Iasi, Romania. The advantages of Ag nanoparticles are durability, heat resistant, low toxicity. Silver is known for its antibacterial qualities for a long time and has been used in medicine in topical treatment.

  10. Preparation and Application of Active Composite Antibacterial Material Containing Ag + and Zn2+

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A kind of active composite antibacterial material was prepared with CaHPO4 as the container,Ag + and Zn2+ were adsorbed through ion-exchange, then it was doped with small scale of rare earth and photocatalyst, and was finally calcined at a certain temperature. The properties and application of the composite material antibacterial were investigated. Some tests show that the as-prepared antibacterial powders modified by opaque agents such as SnO2 and ZrO2 , possess beautiful white and excellent climate resistance at normal temperatures and are promising candidate materials for antibacterial plastics and dope. The result of the application in glaze indicates that Ag + can still exist stably, with no color change for the glaze, even being sintered at 1 200 ℃.SEM, EDS, antibacterial activity analyses and contrast tests reveal that the as-prepared antibacterial powders and the antibacterial glaze both have excellent antibacterial activities, without color change, in the case of dark or brightness.

  11. Antioxidant and antibacterial activity of different parts of Leucas aspera

    Institute of Scientific and Technical Information of China (English)

    Ai Lan Chew; Jeyanthi James Antony Jessica; Sreenivasan Sasidharan

    2012-01-01

    Objective: To evaluate antioxidant, antimicrobial and cytotoxic activity of different parts (root, flower, leaf and stem) of Leucas aspera (L. aspera) (Labiatae). Methods: Different parts of L. aspera were extracted with 80% (v/v) methanol. The methanol extracts were subjected to antioxidant, antimicrobial and brine shrimp lethality assay. Results: All the extracts showed moderate to potent antioxidant activity, among which the root extract demonstrated the strongest antioxidant activity with the IC50 value of 6.552 μg/mL. Methanol extract of root possessed antioxidant activity near the range of vitamin E and thus could be a potential rich source of natural antioxidant. In case of antimicrobial screening, crude extracts of root, flower, leaf and stem showed notable antibacterial activity against tested microorganisms. The root extract showed the highest mean zone of inhibition ranging from 9.0-11.0 mm against tested microorganisms, at a concentration of 100 mg/mL. In the brine shrimp lethality bioassay, it was evident that the methanol root extract did not show significant toxicity. The LC50 value for 12 h and 24 h observation was 2.890 mg/mL and 1.417 mg/mL, respectively. Conclusions: The present finding suggests that the methanol root extract of L. aspera could be developed as pharmaceutical products.

  12. Chemical profiling of Centella asiatica under different extraction solvents and its antibacterial activity, antioxidant activity

    Directory of Open Access Journals (Sweden)

    Supawan Rattanakom

    2015-12-01

    Full Text Available Centella asiatica (L urban, synonym Hydrocotyle asiatica, is found almost all over the world. This plant is famous in Ayurvedic medicine and used in the management of central nervous system, skin and gastrointestinal disorder. Thus this research had been done to evaluate the effect of solvent extraction (Ethanol, Chloroform and Hexane of C. asiatica on chemical profile, antioxidant activity and antibacterial activity against some foodborne pathogens. The result showed that all solvents (ethanol, chloroform and hexane used in extraction showed antibacterial activity against Salmonella enterica Typhimurium U302, S. enterica Enteritidis, S. enterica 4,5,12:I human (US clone, Bacillus cereus and B. subtilis at 50mg/ml concentration. In antioxidant part, ethanolic extract gave highest phenolic content and FRAP value. The results also showed that different extraction solvent gave different chemical profile. Hexane extract C. asiatica showed lowest in both antibacterial and antioxidant activity. Ethanolic and chloroform extract of C. asiatica showed promising potential in both antibacterial and antioxidant activity.

  13. Analysis of Phytochemicals, Antibacterial and Antioxidant activities of Moringa oleifera Lam. Leaf extract- an in vitro study

    Directory of Open Access Journals (Sweden)

    Malliga Elangovan

    2014-12-01

    Full Text Available The leading important things about utilizing plant-derived medication are relatively less dangerous than artificial drugs and provide deep restorative benefits. In this regard, Moringa oleifera plant was evaluated for its nutritional effects. The phytochemical study, antibacterial activity and the in vitro antioxidant activity of aqueous, chloroform and petroleum ether extracts of Moringa oleifera leaves were investigated. Phytochemical analysis revealed the presence of alkaloids, flavonoids, steroids, tannins, saponins and glycosides as major components. The Petroleum ether extracts of Moringa oleifera contains the high content of bioactive compounds such as phenol and flavonoids. The extracts were screened for in vitro antibacterial potential against enteric pathogenic bacteria such as Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, E. coli and Vibrio cholera by disc diffusion method. Moringa oleifera showed potent antibacterial activity against several gram negative and gram positive bacteria. Antioxidants are shown to play an important position in your body immune system next to Reactive oxygen species (ROS. The enzymatic and non-enzymatic activities of SOD, Catalase, Peroxidase, Vitamin C, Carotenoids, and reduced Glutathione were high in petroleum ether extracts of Moringa oleifera. It shows high scavenging activity against DPPH, Nitrous Oxide and Hydroxyl Radical scavenging assays. As a result, Moringa oleifera possesses a good antioxidant, it has a scavenging property against ROS and also it has good antibacterial properties. Thus, Moringa oleifera can be used to synthesize a new drug preparation against various diseases responsible for severe illness.

  14. Antibacterial performance of polypropylene nonwoven fabric wound dressing surfaces containing passive and active components

    Science.gov (United States)

    Xin, Zhirong; Du, Shanshan; Zhao, Chunyu; Chen, Hao; Sun, Miao; Yan, Shunjie; Luan, Shifang; Yin, Jinghua

    2016-03-01

    A growing number of wound dressing-related nosocomial infections necessitate the development of novel antibacterial strategies. Herein, polypropylene non-woven fabric (PPNWF) was facilely modified with passive and active antibacterial components, namely photografting polymerization both N-Vinyl-2-pyrrolidone (NVP) and glycidyl methacrylate (GMA) monomers, and the introduction of guanidine polymer through the reaction between active amino groups and epoxy groups. The modified samples were confirmed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), respectively. Water contact angle measurement, antibacterial test, platelet and red blood cell adhesion were used to evaluate the hydrophilicity, antibacterial properties and hemocompatibility of the samples. It was found that the antibacterial properties were obviously enhanced, meanwhile significantly suppressing platelet and red blood cell adhesion after the above modification. This PPNWF samples that possess antifouling and antimicrobial properties, have great potential in wound dressing applications.

  15. Evaluation of antibacterial activity of Coriandrum sativum (L. against gram and ndash; positive and gram and ndash; negative bacteria

    Directory of Open Access Journals (Sweden)

    D. Sambasivaraju

    2016-12-01

    Conclusions: Coriander oil demonstrated good anti-bacterial activity against commonly five occurring microorganisms but further extensive studies are required to isolate the active ingredient responsible for antibacterial action and develop coriander essential oil as a clinically proven antibacterial agent. [Int J Basic Clin Pharmacol 2016; 5(6.000: 2653-2656

  16. SCREENING OF SECONDARY METABOLITES AND ANTIBACTERIAL ACTIVITY OF ACACIA CONCINNA LEAVES

    Directory of Open Access Journals (Sweden)

    Xavier Vergeese raja

    2012-10-01

    Full Text Available The preliminary phytochemical study and in vitro antibacterial activity of the leaf extracts of Acacia concinna having ethno medicinal uses were investigated. The preliminary phytochemical analysis of the extracts revealed the presence of phenol, tannin, fat and fixed oil, flavanoids, saponin and quinone. The extracts were subjected for screening of in vitro antibacterial activity against various pathogens at the concentrations of 500 and 250 µg/ml by well diffusion assay method. The results of antibacterial activity revealed that all the extract showed good inhibitory activity against all the tested pathogens and the chloroform extract showed comparative by better activity than the other extracts against S.pyogens and s. aureus. The activities of the extract were compared with standard antibiotics. These results indicate that A. concinna leaves possesses potential broad spectrum antibacterial activity.

  17. Antibacterial Activity of Long-Chain Fatty Alcohols against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Yoshihiro Inoue

    2007-02-01

    Full Text Available The antibacterial activity against Staphylococcus aureus of long-chain fatty alcohols was investigated, with a focus on normal alcohols. The antibacterial activity varied with the length of the aliphatic carbon chain and not with the water/octanol partition coefficient. 1-Nonanol, 1-decanol and 1-undecanol had bactericidal activity and membrane-damaging activity. 1-Dodecanol and 1-tridecanol had the highest antibacterial activity among the long-chain fatty alcohols tested, but had no membrane-damaging activity. Consequently, it appears that not only the antibacterial activity but also the mode of action of long-chain fatty alcohols might be determined by the length of the aliphatic carbon chain.

  18. Antibacterial activity of silver nanoparticles stabilized on tannin-grafted collagen fiber

    Energy Technology Data Exchange (ETDEWEB)

    He Li [National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065 (China); Gao Siying; Wu Hao [Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu 610065 (China); Liao Xuepin, E-mail: xpliao@scu.edu.cn [Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu 610065 (China); He Qiang [National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065 (China); Shi Bi, E-mail: sibitannin@vip.163.com [National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065 (China) and Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu 610065 (China)

    2012-07-01

    Bayberry tannin (BT), a typical plant polyphenol, was grafted on collagen fiber (CF) in different mass ratios. Subsequently, the BT-grafted CF (BT-CF) was used as carrier and stabilizer to prepare BT-CF stabilized silver nanoparticles (BT-CF-AgNPs). Scanning Electron Microscopy image of BT-CF-AgNPs showed that the BT-CF-AgNPs was in ordered fibrous state. X-ray Diffraction patterns and Transmission Electron Microscopy images offered evidence that the Ag nanoparticles were well dispersed on BT-CF. Fourier Transform-Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) investigations revealed that the Ag NPs were stabilized by the phenolic hydroxyls and quinones of BT on CF through electron donation/acception interaction. Antibacterial experiments demonstrated that BT-CF-AgNPs exhibited high antibacterial activity. When cell suspensions of Escherichia coli and Staphylococcus aureus (10{sup 4}-10{sup 5} cfu/mL) were contacted with BT{sub 0.19}-CF-AgNPs (mass ratio of BT to CF = 0.19, conc. of Ag = 8 {mu}g/mL) at 310 K under constant shaking, the number of cells went down to zero within 2 h. In addition, the minimal inhibitory concentration of BT{sub 0.19}-CF-AgNPs against Escherichia coli, Staphylococcus aureus, Penicillium glaucum and Saccharomyces cerevisiae was 2 {mu}g/mL, 4 {mu}g/mL, 6 {mu}g/mL and 12 {mu}g/mL Ag, respectively. During recycling use, the antibacterial activity of BT{sub 0.19}-CF-AgNPs against Escherichia coli can last for 5 cycles. These facts suggest that BT-CF-AgNPs can be used as a new and effective antibacterial agent. - Highlights: Black-Right-Pointing-Pointer Bayberry tannin-grafted collagen fiber can be acted as carrier and stabilizer for the preparation of nano-silver (AgNPs) with different particle size. Black-Right-Pointing-Pointer Bayberry tannin-grafted collagen fiber stabilized silver nanoparticles (BT-CF-AgNPs) were characterized by SEM, XRD, TEM, FTIR and XPS. Black-Right-Pointing-Pointer BT-CF-AgNPs has the

  19. Assessment of Tamarindus indica extracts for antibacterial activity.

    Science.gov (United States)

    Nwodo, Uchechukwu U; Obiiyeke, Grace E; Chigor, Vincent N; Okoh, Anthony I

    2011-01-01

    Ethanolic and aqueous (hot and cold) extracts of the fruit pulp, stem bark and leaves of Tamarindus indica were evaluated for antibacterial activity, in vitro, against 13 Gram negative and 5 Gram positive bacterial strains using agar well diffusion and macro broth dilution techniques, simultaneously. The fruit pulp extracts exhibited a wide spectrum of activity; the cold water extract against 95.5% of the test bacterial strains; and the hot water and ethanolic extracts against 90.9% and 86.4%, respectively. In contrast the cold water extract of the leaves and stem bark, each was active against 16.7%; while the ethanolic extract of each was active against 75% of the test strains. The minimum inhibitory concentrations (MIC) ranged from 7.81 mg/mL against Bacillus subtilis ATCC 6051 to 31.25 mg/mL against Escherichia coli ATCC 11775; and the minimum bactericidal concentration (MBC) ranged from 125 mg/mL against Pseudomonas aeruginosa ATCC 10145 to 250 mg/mL against Bacillus subtilis ATCC 6051.

  20. Antibacterial activity of indole alkaloids from Aspidosperma ramiflorum

    Directory of Open Access Journals (Sweden)

    J.C.A. Tanaka

    2006-03-01

    Full Text Available We evaluated the antibacterial activities of the crude methanol extract, fractions (I-V obtained after acid-base extraction and pure compounds from the stem bark of Aspidosperma ramiflorum. The minimum inhibitory concentration (MIC was determined by the microdilution technique in Mueller-Hinton broth. Inoculates were prepared in this medium from 24-h broth cultures of bacteria (10(7 CFU/mL. Microtiter plates were incubated at 37ºC and the MICs were recorded after 24 h of incubation. Two susceptibility endpoints were recorded for each isolate. The crude methanol extract presented moderate activity against the Gram-positive bacteria B. subtilis (MIC = 250 µg/mL and S. aureus (MIC = 500 µg/mL, and was inactive against the Gram-negative bacteria E. coli and P. aeruginosa (MIC > 1000 µg/mL. Fractions I and II were inactive against standard strains at concentrations of 1000 µg/mL. Fractions III, IV and V were then submitted to bioassay-guided fractionation by silica gel column chromatography, yielding individual purified ramiflorines A and B. Both ramiflorines showed significant activity against S. aureus (MIC = 25 µg/mL and E. faecalis (MIC = 50 µg/mL, with EC50 of 8 and 2.5 µg/mL for ramiflorines A and B, respectively, against S. aureus. These results are promising, showing that these compounds are biologically active against Gram-positive bacteria.

  1. Chemical composition and antibacterial activity of Gongronema latifolium

    Institute of Scientific and Technical Information of China (English)

    ELEYINMI Afolabi F.

    2007-01-01

    Chemical composition of Gongronema latifolium leaves was determined using standard methods. Aqueous and methanol G. latifolium extracts were tested against thirteen pathogenic bacterial isolates. Crude protein, lipid extract, ash, crude fibre and nitrogen free extractives obtained are: 27.2%, 6.07%, 11.6%, 10.8% and 44.3% dry matter respectively. Potassium,sodium, calcium, phosphorus and cobalt contents are 332, 110, 115, 125 and 116 mg/kg respectively. Dominant essential amino acids are leucine, valine and phenylalanine. Aspartic acid, glutamic acid and glycine are 13.8%, 11.9% and 10.3% respectively of total amino acid. Saturated and unsaturated fatty acids are 50.2% and 39.4% of the oil respectively. Palmitic acid makes up 36% of the total fatty acid. Extracts show no activity against E. faecalis, Y. enterolytica, E. aerogenes, B. cereus and E. agglomerans.Methanol extracts were active against S. enteritidis, S. cholerasius ser typhimurium and P. aeruginosa (minimum inhibitory concentration (MIC) 1 mg; zone of growth inhibition 7, 6.5 and 7 mm respectively). Aqueous extracts show activity against E. coli (MIC 5 mg) and P. aeruginosa (MIC 1 mg) while methanol extracts are active against P. aeruginosa and L. monocytogenes. G.latifolium has potential food and antibacterial uses.

  2. Assessment of Tamarindus indica Extracts for Antibacterial Activity

    Directory of Open Access Journals (Sweden)

    Anthony I. Okoh

    2011-09-01

    Full Text Available Ethanolic and aqueous (hot and cold extracts of the fruit pulp, stem bark and leaves of Tamarindus indica were evaluated for antibacterial activity, in vitro, against 13 Gram negative and 5 Gram positive bacterial strains using agar well diffusion and macro broth dilution techniques, simultaneously. The fruit pulp extracts exhibited a wide spectrum of activity; the cold water extract against 95.5% of the test bacterial strains; and the hot water and ethanolic extracts against 90.9% and 86.4%, respectively. In contrast the cold water extract of the leaves and stem bark, each was active against 16.7%; while the ethanolic extract of each was active against 75% of the test strains. The minimum inhibitory concentrations (MIC ranged from 7.81 mg/mL against Bacillus subtilis ATCC 6051 to 31.25 mg/mL against Escherichia coli ATCC 11775; and the minimum bactericidal concentration (MBC ranged from 125 mg/mL against Pseudomonas aeruginosa ATCC 10145 to 250 mg/mL against Bacillus subtilis ATCC 6051.

  3. Antibacterial activity of flavonoids of Withania somnifera L.

    Directory of Open Access Journals (Sweden)

    Geeta Singh

    2014-01-01

    Full Text Available Context: Flavonoids from different parts (leaf, stem, root and fruits of Withania somnifera have been screened for antibacterial activity against Enterobacter aerogens, Bacillus subtilis, Klebsiella pneumoniae, Raoultella planticola and Agrobacterium tumefaciens. Materials and Methods: Disc diffusion assay (DDA was performed for antimicrobial screening. Minimum inhibitory concentration (MIC, minimum bactericidal (MBC and total activity (TA of extracts found sensitive against test pathogens have also been evaluated. Results and Conclusions: Most susceptible microorganisms in the present study were R. planticola and A. tumefaciens, which had shown susceptibility for almost all the extracts tested. Thereafter sensitive was shown by K. pneumoniae, B. subtilis, E. aerogens. However, highest inhibition zone was observed for E. aerogens (IZ 25.5 mm; AI 1.159 ± 0.023 followed by R. planticola (IZ 22 mm; AI 0.733 ± 0.133. Antimicrobial activity of flavonoids extracts of W. somnifera were carried out to validate the use of traditional medicinal herb and the results of this study tend to give credence to the common use of W. sominfera plant. The study provide platform for further studies in plant, so as to pinpoint specific alkaloids and/or flavonoids responsible for antimicrobial activity and might open new vistas in the therapeutic use of the plant in allopathy medicine too.

  4. Antibacterial and antioxidant activities of three endemic plants from Algerian Sahara

    Directory of Open Access Journals (Sweden)

    ELmouloud Bouchouka

    2012-03-01

    Full Text Available Background. Saharan plants are known by their high content of antioxidant products like phenolic compounds due to the extreme climatic conditions. They constitute the basis of treatments used by local population for various diseases. The purposes of this study were to measure the total phenolic compounds and total fl avonoid compounds, to determine antioxidant capacity, and to evaluate the antibacterial activity of three wild Saharan medicinal plants. Material and methods. Hexane and ethyl acetate fractions of ethanol:water extract and the residu of the extracted aqueous layer of Ferula vesceritensis fruits, Genista saharae aerial parts and Zilla macropterae fruits were assayed to determine their antibacterial activity using the disc diffusion method against: Escherichia coli (ATCC 25922, Staphylococcus aureus (ATCC 25923 and Pseudomonas aeruginosa (ATCC 27853. In addition, the total phenolic compounds and total fl avonoids and antioxydant activity using DPPH test of ethyl acetate fractions (EAF of plant parts studied were investigated. Gallic acid, quercetin and vitamin C were used for these parameters. Results. Among the extracts tested, ethyl acetate fractions of all plants and hexane fraction of F. vesceritensis showed activity against S. aureus. Good activity was shown by EAF of G. saharae. According to the results, it is observed that Z. macropterae fruits possess a good antioxidant activity. Conclusion. The results indicate that the ethyl acetate fraction of G. sahara Aerial parts possesses a good antibacterial activity against S. aureus, which justifi es its use in traditional medicine for treating respiratory diseases. Furthermore, evaluation of in vitro antioxidant capacity of Ethyl acetate fractions of these plants, particular Z. macroptera fruits, has also provided interesting results. Zilla macroptera fruits may therefore be a good source of antioxidants.

  5. Study of the antibacterial and antifungal activities of synthetic benzyl bromides, ketones, and corresponding chalcone derivatives

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    Shakhatreh MA

    2016-11-01

    Full Text Available Muhamad Ali K Shakhatreh,1 Mousa L Al-Smadi,2 Omar F Khabour,1,3 Fatima A Shuaibu,1 Emad I Hussein,4 Karem H Alzoubi51Department of Medical Laboratory Sciences, 2Department of Applied Chemical Sciences, Jordan University of Science and Technology, Irbid, Jordan; 3Faculty of Applied Medical Sciences, Taibah University, Madina, Saudi Arabia; 4Department of Biological Sciences, Yarmouk University, 5Department of Clinical Pharmacy, Jordan University of Science and Technology, Irbid, Jordan Abstract: Several applications of chalcones and their derivatives encouraged researchers to increase their synthesis as an alternative for the treatment of pathogenic bacterial and fungal infections. In the present study, chalcone derivatives were synthesized through cross aldol condensation reaction between 4-(N,N-dimethylaminobenzaldehyde and multiarm aromatic ketones. The multiarm aromatic ketones were synthesized through nucleophilic substitution reaction between 4-hydroxy acetophenone and benzyl bromides. The benzyl bromides, multiarm aromatic ketones, and corresponding chalcone derivatives were evaluated for their activities against eleven clinical pathogenic Gram-positive, Gram-negative bacteria, and three pathogenic fungi by the disk diffusion method. The minimum inhibitory concentration was determined by the microbroth dilution technique. The results of the present study demonstrated that benzyl bromide derivatives have strong antibacterial and antifungal properties as compared to synthetic chalcone derivatives and ketones. Benzyl bromides (1a and 1c showed high ester activity against Gram-positive bacteria and fungi but moderate activity against Gram-negative bacteria. Therefore, these compounds may be considered as good antibacterial and antifungal drug discovery. However, substituted ketones (2a–b as well as chalcone derivatives (3a–c showed no activity against all the tested strains except for ketone (2c, which showed moderate activity against

  6. ZnO/graphite composites and its antibacterial activity at different conditions.

    Science.gov (United States)

    Dědková, Kateřina; Janíková, Barbora; Matějová, Kateřina; Čabanová, Kristina; Váňa, Rostislav; Kalup, Aleš; Hundáková, Marianna; Kukutschová, Jana

    2015-10-01

    The paper reports laboratory preparation, characterization and in vitro evaluation of antibacterial activity of ZnO/graphite nanocomposites. Zinc chloride and sodium carbonate served as precursors for synthesis of zinc oxide, while micromilled and natural graphite were used as the matrix for ZnO nanoparticles anchoring. During the reaction of ZnCl2 with saturated aqueous solution of Na2CO3a new compound is created. During the calcination at the temperature of 500 °C this new precursors decomposes and ZnO nanoparticles are formed. Composites ZnO/graphite with 50 wt.% of ZnO particles were prepared. X-ray powder diffraction and Raman microspectroscopy served as phase-analytical methods. Scanning electron microscopy technique was used for morphology characterization of the prepared samples and EDS mapping for visualization of elemental distribution. A developed modification of the standard microdilution test was used for in vitro evaluation of daylight induced antibacterial activity and antibacterial activity at dark conditions. Common human pathogens served as microorganism for antibacterial assay. Antibacterial activity of ZnO/graphite composites could be based on photocatalytic reaction; however there is a role of Zn(2+) ions on the resulting antibacterial activity which proved the experiments in dark condition. There is synergistic effect between Zn(2+) caused and reactive oxygen species caused antibacterial activity. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Comparative study of hypoglycemic and antibacterial activity of organic extracts of four Bangladeshi plants

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    Mohammad Shah Hafez Kabir

    2016-03-01

    ]. Only methanol extract of A. bulbifer showed (8.50 ± 0.50 mm and (7.20 ± 0.76 mm zone of inhibition against Pseudomomas aeruginosa at 1 000 and 800 µg/disk dose respectively. Conclusions: Through our study, it was found that S. colocasiifolia could be considered as very promising and beneficial hypoglycemic agent. Although C. recurvata and S. colocasiifolia showed comparable high antibacterial activity, further studies should be needed to develop new antibacterial agent from them. S. colocasiifolia may be a potential source for the development of new oral hypoglycemic agent.

  8. Antibacterial activity of neem nanoemulsion and its toxicity assessment on human lymphocytes in vitro.

    Science.gov (United States)

    Jerobin, Jayakumar; Makwana, Pooja; Suresh Kumar, R S; Sundaramoorthy, Rajiv; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2015-01-01

    Neem (Azadirachta indica) is recognized as a medicinal plant well known for its antibacterial, antimalarial, antiviral, and antifungal properties. Neem nanoemulsion (NE) (O/W) is formulated using neem oil, Tween 20, and water by high-energy ultrasonication. The formulated neem NE showed antibacterial activity against the bacterial pathogen Vibrio vulnificus by disrupting the integrity of the bacterial cell membrane. Despite the use of neem NE in various biomedical applications, the toxicity studies on human cells are still lacking. The neem NE showed a decrease in cellular viability in human lymphocytes after 24 hours of exposure. The neem NE at lower concentration (0.7-1 mg/mL) is found to be nontoxic while it is toxic at higher concentrations (1.2-2 mg/mL). The oxidative stress induced by the neem NE is evidenced by the depletion of catalase, SOD, and GSH levels in human lymphocytes. Neem NE showed a significant increase in DNA damage when compared to control in human lymphocytes (P<0.05). The NE is an effective antibacterial agent against the bacterial pathogen V. vulnificus, and it was found to be nontoxic at lower concentrations to human lymphocytes.

  9. Terrestrial actinomycetes from diverse locations of Uttarakhnad, India: Isolation and screening for their antibacterial activity.

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    Vijay Kumar

    2013-09-01

    Full Text Available Uttarakhand region is less explored, but possess a great biodiversity. This diversity can be explored for isolation and characterization of new actinomycetes strains for seeking antimicrobial molecules. It can therefore be predicted that novel bioactive metabolite producing actinomycetes can be discovered to combat multidrug resistant bacterial pathogens.Variations in the viable count of actinomycetes were accessed in different altitudes. Actinomycetes were isolated, indentified and screened for their antibacterial activity.The highest viable counts of actinomycetes were recorded in valleys followed by mid hills and high hills. A total of 512 actinomycetes were isolated which were found to belong the 14 different genera of actinomycetes. Mainly the genus Streptomyces was dominant in all the soil samples. Out of 512 isolates recovered, 23.44% exhibited antibacterial activity against one or more tested bacterial pathogens. Of these 56.67% showed activity against Gram-positive bacteria, 26.67% against Gram-negative bacteria while 16.67% showed broad spectrum activity. Isolate DV1S and GR9a-5 showed highest antibacterial properties against several multi-drug resistant bacterial pathogens and were identified using polyphasic approach. DV1S and GR9a-5 were found to be most closely related with S. massasporeus NBRC 12796(T and Nocardia nova JCM 6044(T respectively.The results of this study strongly support the idea that the viable count of actinomycetes varied greatly with altitude. The actinomycetes species isolated from valleys, mid hills and high hills possess significant capacity to produce compounds which are active against several drug resistant bacterial pathogens.

  10. Synthesis, Structure and Antibacterial Activities of 4-BBTS Schiff Base and Its Complexes

    Institute of Scientific and Technical Information of China (English)

    LI Pei-Fan; LIU Bin; WANG Jin-Ling

    2007-01-01

    4-Bromobenzaldehyde thiosemicarbazone Schiff base (4-BBTS) and its Cu(Ⅱ),Zn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) complexes were synthesized and characterized by elemental analysis, UV,IR, MS, 1H NMR, and molar conductivity. Using disc diffusion method, the antibacterial activity tests were conducted. The results revealed that the ligand as well as all the complexes exhibits good antibacterial activities against E. Coli. and S. Aureus. Moreover, Cu(Ⅱ) complex shows the best antibacterial activity, which provides beneficial reference for studying the relationship between the structures and performances.

  11. Antibacterial Activity and Cytotoxicity of Gold (I) and (III) Ions and Gold Nanoparticles

    OpenAIRE

    Shareena Dasari, TP; Zhang, Y; Yu, H.

    2015-01-01

    Gold nanoparticles (AuNPs) and gold ion complexes have been investigated for their antibacterial activities. However, the majority of the reports failed to disclose the concentration of free Au(I) or Au(III) present in solutions of AuNPs or gold ion complexes. The inconsistency of antibacterial activity of AuNPs may be due to the effect of the presence of Au(III). Here we report the antibacterial activity of Au(I) and Au(III) to four different bacteria: one nonpathogenic bacterium: E. coli an...

  12. Antibacterial activity of Myrciaria dubia (Camu camu) against Streptococcus mutans and Streptococcus sanguinis

    Institute of Scientific and Technical Information of China (English)

    Rosella Camere-Colarossi; Gabriela Ulloa-Urizar; Dyanne Medina-Flores; Stefany Caballero-Garca; Frank Mayta-Tovalino; Juana del Valle-Mendoza

    2016-01-01

    Objective: To evaluate the antibacterial and cytotoxic effect of Myrciaria dubia (Camu camu) (M. dubia) methanol extract, against Streptococcus mutans (ATCC 25175) (S. mutans) and Streptococcus sanguinis (ATCC 10556) (S. sanguinis). Methods: Two methanol extracts of M. dubia were prepared in vitro, from the seeds and pulp. Ten independent tests were prepared for each type of extract, using 0.12% chlor-hexidine solution as positive control. Agar diffusion test was used by preparing wells with the experimental solutions cultivated in anaerobic conditions for 48 h at 37 ° C. Mean-while, the minimum inhibitory concentration and the cytotoxic effect over MDCK cell line was found. Results: A higher antibacterial effect was observed with the methanol seed extract with an inhibitory halo of (21.36 ± 6.35) mm and (19.21 ± 5.18) mm against S. mutans and S. sanguinis, respectively. The methanol extract of the pulp had an effect of (16.20 ± 2.08) mm and (19.34 ± 2.90) mm, respectively. The minimum inhibitory concentration of the pulp extract was 62.5μg/mL for both strains, whereas for the seed antibacterial activity was observed even at low concentrations. The CC50 of the seeds extract was at a higher con-centration than 800μg/mL and 524.37μg/mL for the pulp extract. Conclusions: The experimental findings demonstrated the antibacterial effect of the methanol extract of M. dubia against S. mutans and S. sanguinis. These extracts were not cytotoxic at high concentrations.

  13. Antibacterial and Antioxidant Activities of Ursolic Acid and Derivatives

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    Patrícia G.G. do Nascimento

    2014-01-01

    Full Text Available Ursolic acid, an important bioactive compound, was isolated from ethanol extract of aerial parts of Sambucus australis. In order to develop bioactive ursolic acid derivatives, two semi-synthetic compounds were obtained through modification at C-3. The antibacterial activity of the ursolic acid and its derivatives was investigated. The microdilution method was used for determination of the minimal inhibitory concentration (MIC, against twelve bacterial strains. The influence of ursolic acid and its derivatives on the susceptibility of some bacterial pathogens to the aminoglycosides antibiotics neomycin, amikacin, kanamycin and gentamicin was evaluated. The most representative synergistic effect was observed by 3β-formyloxy-urs-12-en-28-oic acid at the concentration of 64 μg/mL in combination with kanamycin against Escherichia coli (27, a multidrug-resistant clinical isolate from sputum, with reduction of MIC value from 128 μg/mL to 8 μg/mL. Ursolic acid and its derivatives were examined for their radical scavenger activity using the DPPH assay, and showed significant activity.

  14. Anticandidal, antibacterial, cytotoxic and antioxidant activities of Calendula arvensis flowers.

    Science.gov (United States)

    Abudunia, A-M; Marmouzi, I; Faouzi, M E A; Ramli, Y; Taoufik, J; El Madani, N; Essassi, E M; Salama, A; Khedid, K; Ansar, M; Ibrahimi, A

    2016-12-20

    Calendula arvensis (CA) is one of the important plants used in traditional medicine in Morocco, due to its interesting chemical composition. The present study aimed to determine the anticandidal, antioxidant and antibacterial activities, and the effects of extracts of CA flowers on the growth of myeloid cancer cells. Also, to characterize the chemical composition of the plant. Flowers of CA were collected based on ethnopharmacological information from the villages around the region Rabat-Khemisset, Moroccco. The hexane and methanol extracts were obtained by soxhlet extraction, while aqueous extracts was obtained by maceration in cold water. CA extracts were assessed for antioxidant activity using four different methods (DPPH, FRAP, TEAC, β-carotene bleaching test). Furthermore, the phenolic and flavonoid contents were measured, also the antimicrobial activity has been evaluated by the well diffusion method using several bacterial and fungal strains. Finally, extracts cytotoxicity was assessed using MTT test. Phytochemical quantification of the methanolic and aqueous extracts revealed that they were rich with flavonoid and phenolic content and were found to possess considerable antioxidant activities. MIC values of methanolic extracts were 12.5-25μg/mL. While MIC values of hexanolic extracts were between 6.25-12.5μg/mL and were bacteriostatic for all bacteria while methanolic and aqueous extracts were bactericidal. In addition, the extracts exhibited no activity on Candida species except the methanolic extract, which showed antifungal activity onCandida tropicalis 1 and Candida famata 1. The methanolic and aqueous extracts also exhibited antimyeloid cancer activity (IC50 of 31μg/mL). In our study, we conclude that the methanolic and aqueous extracts were a promising source of antioxidant, antimicrobial and cytotoxic agents.

  15. Brine shrimp lethality and antibacterial activity of extracts from the bark of Schleichera oleosa

    Institute of Scientific and Technical Information of China (English)

    Laxman Pokhrel; Bigyan Sharma; Gan B Bajracharya

    2015-01-01

    Objective: To determine the antibacterial efficacy and brine shrimp toxicity of extracts (hexane, dichloromethane, ethyl acetate, methanol and water) obtained from the bark of Schleichera oleosa. Methods: The powdered bark sample was Soxhlet extracted sequentially in hexanes, dichloromethane, ethyl acetate, methanol and water. Antibacterial evaluation was carried out by following the agar diffusion method and amoxicillin disc was used as a reference. Slightly modified Meyer’s method was used to determine the toxicity of the extracts in brine shrimps. Results: Among the nine bacterial strains tested, the methanolic and aqueous extracts showed promising antibacterial efficacy against Serratia marcescens, Escherarichia coli, Bacillus subtilis and Micrococcus luteus. None of the extracts were found significantly toxic to brine shrimps. Conclusions: Strong antibacterial activity and low brine shrimp toxicity of methanolic and aqueous extracts can provide new antibacterial compounds.

  16. Brine shrimp lethality and antibacterial activity of extracts from the bark of Schleichera oleosa

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    Laxman Pokhrel

    2015-08-01

    Full Text Available Objective: To determine the antibacterial efficacy and brine shrimp toxicity of extracts (hexane, dichloromethane, ethyl acetate, methanol and water obtained from the bark of Schleichera oleosa. Methods: The powdered bark sample was Soxhlet extracted sequentially in hexanes, dichloromethane, ethyl acetate, methanol and water. Antibacterial evaluation was carried out by following the agar diffusion method and amoxicillin disc was used as a reference. Slightly modified Meyer’s method was used to determine the toxicity of the extracts in brine shrimps. Results: Among the nine bacterial strains tested, the methanolic and aqueous extracts showed promising antibacterial efficacy against Serratia marcescens, Escherarichia coli, Bacillus subtilis and Micrococcus luteus. None of the extracts were found significantly toxic to brine shrimps. Conclusions: Strong antibacterial activity and low brine shrimp toxicity of methanolic and aqueous extracts can provide new antibacterial compounds.

  17. In vitro antibacterial activity of Sri Lankan orthodox black tea (Camellia sinensis L.) belonging to different agro-climatic elevations

    Institute of Scientific and Technical Information of China (English)

    Wanigasekara Daya Ratnasooriya; Sachitra Gayanthi Ratnasooriya; Ranga Dissanayake

    2016-01-01

    Objective:To investigate the antibacterial properties of three grades of orthodox Sri Lankan black tea belonging to the three agro-climatic elevations. Methods: Methanloic extracts of orange pekoe (OP), broken orange pekoe fannings (BOPF) and Dust No. 1 belonging to three agro-climatic elevations (low, mid and high grown) were made and testedin vitro (concentration: 300µg/disc) against Gram-positive pathogenic bacteria,Staphylococcus aureus(ATCC25923) (S. aureus) andBacillus cereus (ATCC11778) (B. cereus), and two Gram-negative bacteriaPseudomonas aeruginosa (ATCC9027) (P. aeruginosa) andEscherichia coli (ATCC35218) (E. coli), using agar disc diffusion assay. Gentamycin (10µg/disc) was used as the positive control and methanol as the negative control. Minimum inhibitory concentration (MIC) values were evaluated, using micro dilution method. Results: None of the tea extracts exerted an antibacterial action againstP. aeruginosa andE. coli. In contrast mild to moderate antibacterial activity was exerted againstS. aureus andB. cereus. Further gentamycin exhibited strong antibacterial activity against all the four bacterial species. Further lowMIC values were evident for tea samples against the two Gram-positive bacteria. The order of anti-bacterial activity for tea extracts was Dust No. 1 >BOPF >OP. Conclusions: It is concluded that Sri Lankan orthodox black tea belonging to Dust No. 1, BOPF, andOP pocessin vitro antibacterial activity againstS. aureus andB. cereus but not against Gram-positive bacteriaP. aeruginosa andE. coli.

  18. Evaluation of Saponin Extract from Vitex doniana and Pentaclethra macrophylla for Antibacterial Activity

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    Nneoma E. Akaniro-Ejim

    2016-06-01

    Full Text Available Saponins are pharmacologically active compounds that have been shown to ameliorate abnormal physiological processes and be aptly applied in folklore for the treatment of maladies occasioned by infectious agents. Consequently, saponins from Vitex doniana and Pentaclethra macrophylla were evaluated for antibacterial properties, as these herbs are used in folk medicine. Dried pulverized plant materials were defatted, and solvents with varying polarity were applied at varying ratios for the extraction of saponins. Phyto-chemistry was in accordance with standard methods, while an antibacterial assay was made through the agar well diffusion and micro broth dilution techniques. Phytochemical quantitation showed high concentrations of tannins, 231 ± 0.6 CE/g, and saponins, 58% from V. doniana. Similarly, P. macrophylla stem bark extract also showed high concentrations of tannins, 309 ± 2.42 CE/g, alkaloids, 71% ± 0.5%, and saponins, 87% ± 3.4%. The ethanol extracts of V. doniana inhibited the growth of Staphylococcus aureus (ATCC 11775 and a clinical strain with inhibition zone ranges of 15.5 ± 2.12 to 7.0 ± 0.0 (mm against leaf extracts and 20.0 ± 1.41 to 7.0 ± 0.0 (mm against stem bark extracts. Conversely, saponin extract from V. doniana showed a broad spectrum of activity, as it inhibited both Gram-negative and -positive test strains, E. coli clinical strain (20.0 ± 1.41 mm, P. aeruginosa clinical strain (18.5 ± 0.71 mm, E. coli ATCC 11775 (17.0 ± 0 mm, and S. aureus clinical strain (13.0 ± 1.41 mm. However, a broad spectrum was similarly achieved with P. macrophylla extracts, as all test bacteria genus was susceptible. Saponin fractions showed a high potency and broad spectrum antibacterial activity and thus a validation of the folklore applications and the potential for use as a drug or drug scaffold.

  19. Assessment of antibacterial activity of different treatment modalities in deciduous teeth: an in vitro study

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    Esra Yesiloz Gokcen

    2016-11-01

    Full Text Available In recent years, different biotechnological materials and modalities with antibacterial activity are being developed for oral cavity disinfection. However, the antimicrobial effects of all these materials have not been studied and understood in detail. Thus, the aim of this study was to compare the antibacterial activity of ozone therapy with dentine-bonding agents (containing antibacterial monomer 12-meth-acryloyloxydodecylpyridinium bromide (MDPB and 10-methacryloyloxydecyl dihydrogen phosphate (MDP and Ca(OH2 for deciduous teeth in vitro. The antibacterial effectiveness of the studied materials was determined by using a tooth cavity model on cylindrical cavities created in 90 deciduous second mandibular molars. Streptococcus mutans suspension was inoculated in the cavities. The teeth were distributed into six study groups (five different modalities and a negative control group. Dentine samples, which were collected from the cavities before and after the treatment sessions, were microbiologically evaluated and the materials’ antibacterial activities were compared. There were statistically significiant differences in the S. mutans counts before and after treatment (P < 0.05. In terms of antibacterial efficiency, 60-second O3 treatment was found to be the most successful method, followed by 30-second O3, Clearfil Protect Bond (containing MDPB, Clearfil SE Bond (containing MDP and Ca(OH2 treatment. The results from this study suggested that longer exposure to ozone might have more beneficial effects in terms of antibacterial activity for reducing the levels of S. mutans.

  20. Antibacterial activity of 2-alkynoic fatty acids against multidrug-resistant bacteria.

    Science.gov (United States)

    Sanabria-Ríos, David J; Rivera-Torres, Yaritza; Maldonado-Domínguez, Gamalier; Domínguez, Idializ; Ríos, Camille; Díaz, Damarith; Rodríguez, José W; Altieri-Rivera, Joanne S; Ríos-Olivares, Eddy; Cintrón, Gabriel; Montano, Nashbly; Carballeira, Néstor M

    2014-02-01

    The first study aimed at determining the structural characteristics needed to prepare antibacterial 2-alkynoic fatty acids (2-AFAs) was accomplished by synthesizing several 2-AFAs and other analogs in 18-76% overall yields. Among all the compounds tested, the 2-hexadecynoic acid (2-HDA) displayed the best overall antibacterial activity against Gram-positive Staphylococcus aureus (MIC=15.6 μg/mL), Staphylococcus saprophyticus (MIC=15.5 μg/mL), and Bacillus cereus (MIC=31.3 μg/mL), as well as against the Gram-negative Klebsiella pneumoniae (7.8 μg/mL) and Pseudomonas aeruginosa (MIC=125 μg/mL). In addition, 2-HDA displayed significant antibacterial activity against methicillin-resistant S. aureus (MRSA) ATCC 43300 (MIC=15.6 μg/mL) and clinical isolates of MRSA (MIC=3.9 μg/mL). No direct relationship was found between the antibacterial activity of 2-AFAs and their critical micelle concentration (CMC) suggesting that the antibacterial properties of these fatty acids are not mediated by micelle formation. It was demonstrated that the presence of a triple bond at C-2 and the carboxylic acid moiety in 2-AFAs are important for their antibacterial activity. 2-HDA has the potential to be further evaluated for use in antibacterial formulations.

  1. Antibacterial activity of Ulva reticulata from southwest coast of Kanyakumari, India

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    Sundaram Ravikumar

    2016-03-01

    Full Text Available Objective: To evaluate the antibacterial activity of Ulva reticulata species collected from the Kanyakumari coast of India to determine their potential for bioactivity. Methods: The algal extract was prepared using n-butanol for evaluating the antibacterial activity of Salmonella typhi, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Vibrio cholerae, Vibrio parahaemolyticus, Bacillus cereus and Listeria monocytogenes. Results: It was observed that the n-butanolic extract of the seaweed powder of Ulva reticulata (25–100 mg/mL exerted notable antibacterial activity against tested bacterial strains. The maximum antibacterial activity was exhibited against Escherichia coli and Bacillus cereus in all concentrations. Conclusions: The results obtained in the present investigation supported the traditional use of the seaweeds against various infections. However, further investigation has been carried out to elucidate the exact mechanism and isolation of active principle.

  2. Antibacterial activity ofUlva reticulata from southwest coast of Kanyakumari, India

    Institute of Scientific and Technical Information of China (English)

    Sundaram Ravikumar; Lawrance Anburajan; Balakrishnan Meena

    2016-01-01

    Objective:To evaluate the antibacterial activity ofUlva reticulata species collected from the Kanyakumari coast of India to determine their potential for bioactivity. Methods:The algal extract was prepared usingn-butanol for evaluating the antibacterial activity ofSalmonella typhi, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Vibrio cholerae, Vibrio parahaemolyticus, Bacillus cereus andListeria monocytogenes. Results:It was observed that then-butanolic extract of the seaweed powder ofUlva reticulata (25–100 mg/mL) exerted notable antibacterial activity against tested bacterial strains. The maximum antibacterial activity was exhibited againstEscherichia coli andBacillus cereus in all concentrations. Conclusions:The results obtained in the present investigation supported the traditional use of the seaweeds against various infections. However, further investigation has been carried out to elucidate the exact mechanism and isolation of active principle.

  3. EVALUATION OF PHYTOCHEMICAL AND ANTIBACTERIAL ACTIVITY OF BUTEA MONOSPERMA LEAF EXTRACTS

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    K. Rmanjaneyulu

    2011-05-01

    Full Text Available The antibacterial activity of ethanol and aqueous extracts of leaves of Butea monosperma was evaluated on one gram positive strain like Staphylococcus aureus and one gram negative strain like Escherichia coli. The invitro antibacterial activity was performed by disc diffusion method. The disc diffusion method for antibiotic susceptibility testing is the Kirby-Bauer method. The significant antibacterial activity of the active extracts was compared with standard antibiotic gentamicin (40μg/ml.From the experiment done the ethanolic extract of Butea monosperma leaves did produce considerable antibacterial activity than the aqueous extract was observed. In addition the preliminary phytochemical tests of ethanolic and aqueous extract of Butea monosperma leaves revealed the presence of the alkaloids, carbohydrates, tannins, flavanoids, phenolic compounds and starch. The results obtained in the present study suggest that Butea monosperma leaves can be used in treating diseases caused by test organisms.

  4. ANTIBACTERIAL AND CYTOTOXIC ACTIVITIES OF THYMUS VULGARIS LEAVES GROWN IN OMAN

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    Aisha Haroon Al-Balushi, Maryam Aljabri, Md. Sohail Akhtar*, Sadri Said, Afaf Weli, Qasim Al-Riyami and Ahlam A. AlAbri

    2013-11-01

    Full Text Available Thyme (Thymus vulgaris L. is a pleasant smelling perennial shrub, which grows in several regions in the world. The plant is reported to have high economic and medicinal values. The objectives of this research was to determine antimicrobial activity of petroleum ether, chloroform and hydroalcoholic extracts obtained from leaves of Thymus vulgaris collected from Oman. The other objective was to determine cytotoxic activity of the three extracts. Antimicrobial activity was measured using disc diffusion method against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumonia. Brine shrimp test was used to estimate cytotoxic activity. In antibacterial assay, Thymus vulgaris leaves extracts showed very strong results, inhibition zones ranged from 7 – 20 mm. So this plant can be used as a good source of potential antimicrobial agent.Petroleum ether showed the highest antibacterial activity. Furthermore, Petroleum ether and Chloroform extracts have almost killed all the shrimp larvae at higher concentration of 1000 mcg/ml. LC50 values for the two extracts were 85.2 and 95.8 mcg/ml, respectively. Polar fractions like hydro alcoholic extract have displayed very low cytotoxic activities.

  5. Biotransformation of fluoroquinolone antibiotics by ligninolytic fungi--Metabolites, enzymes and residual antibacterial activity.

    Science.gov (United States)

    Čvančarová, Monika; Moeder, Monika; Filipová, Alena; Cajthaml, Tomáš

    2015-10-01

    A group of white rot fungi (Irpex lacteus, Panus tigrinus, Dichomitus squalens, Trametes versicolor and Pleurotus ostreatus) was investigated for the biodegradation of norfloxacin (NOR), ofloxacin (OF) and ciprofloxacin (CIP). The selected fluoroquinolones were readily degraded almost completely by I. lacteus and T. versicolor within 10 and 14 d of incubation in liquid medium, respectively. The biodegradation products were identified by liquid chromatography-mass spectrometry. The analyses indicated that the fungi use similar mechanisms to degrade structurally related antibiotics. The piperazine ring of the molecules is preferably attacked via either substitution or/and decomposition. In addition to the degradation efficiency, attention was devoted to the residual antibiotic activities estimated using Gram-positive and Gram-negative bacteria. Only I. lacteus was able to remove the antibiotic activity during the course of the degradation of NOR and OF. The product-effect correlations evaluated by Principal Component Analysis (PCA) enabled elucidation of the participation of the individual metabolites in the residual antibacterial activity. Most of the metabolites correlated with the antibacterial activity, explaining the rather high residual activity remaining after the biodegradation. PCA of ligninolytic enzyme activities indicated that manganese peroxidase might participate in the degradation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Phenolic content, antioxidant activity, antibacterial activity and phytochemical composition of Garcinia lancifolia

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    R S Policegoudra

    2012-01-01

    Full Text Available Garcinia lancifolia (Clusiaceae is an unexplored medicinal plant used as stomachic, diuretic and its fruit is used to cure dysentery and diarrhoea. The acidic fruits are used to prepare juice, pickle and curries. The phytochemical analysis of different extracts of G. lancifolia leaf, stem and fruit revealed the presence of tannins, saponins, flavonoids, terpenoids, alkaloids and cardiac glycosides. The high phenolic content was observed in the methanol extract of leaf followed by methanol extract of stem and dichloromethane extract of leaf. The G. lancifolia fruit juice exhibited high antibacterial activity against Pseudomonas aeruginosa, Escherichia coli, Micrococcus luteus, Streptococcus mutans, Bacillus mycoides and Bacillus subtilis. The methanol extract of fruit pulp was also very effective against Gram-positive bacteria when compared with Gram-negative bacteria. The radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl was highest in fruit juice followed by methanol extract of leaf and stem. All extracts showed concentration-dependent increase in the antioxidant activity.

  7. Preparation and antibacterial activity of quaternized chitosan with iodine.

    Science.gov (United States)

    Tang, Yang; Xie, Linlin; Sai, Mingze; Xu, Ningning; Ding, Derun

    2015-03-01

    Chitosan (CTS) is a natural polymer with active groups such as -NH2 which can be functionalized to introduce new positively charged N-atoms and protonated amino group for better use. In this study, to improve the stability of iodine, a novel complex (CTS-CTA-I2) was prepared by mixing N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride (CTS-CTA) with iodine in ethanol solution. The CTS-CTA-I2 was characterized by Fourier transform infrared spectra (FTIR), Ultraviolet and visible (UV-vis) spectra and thermal gravimetric analysis (TG). Besides, the interaction of iodine with CTS-CTA was also studied. The mole ratio of CTS-CTA with iodine was measured by iodometric titration method and the max mole ratio of CTS-CTA with iodine was 1:1.33. The antimicrobial activity of CTS, CTS-CTA and CTS-CTS-I2 complexes was investigated against Escherichia coli and Staphylococcus aureus and the antibacterial property of CTS-CTA-I2 was superior to CTS-CTA.

  8. Synergistic antibacterial activity of the essential oil of aguaribay (Schinus molle L.).

    Science.gov (United States)

    de Mendonça Rocha, Pedro M; Rodilla, Jesus M; Díez, David; Elder, Heriberto; Guala, Maria Silvia; Silva, Lúcia A; Pombo, Eunice Baltazar

    2012-10-12

    Schinus molle L. (aguaribay, aroeira-falsa, "molle", family Anacardiaceae), a native of South America, produces an active antibacterial essential oil extracted from the leaves and fruits. This work reports a complete study of its chemical composition and determines the antibacterial activity of Schinus molle L. essential oil and its main components. The results showed that the crude extract essential oil has a potent antibacterial effect on Staphylococcus aureus ATCC 25923, a strong/moderate effect on Escherichia coli ATCC 25922 and moderate/weak one on Pseudomonas aeruginosa ATCC 27853.

  9. Synergistic Antibacterial Activity of the Essential Oil of Aguaribay (Schinus molle L.

    Directory of Open Access Journals (Sweden)

    Lúcia A. Silva

    2012-10-01

    Full Text Available Schinus molle L. (aguaribay, aroeira-falsa, “molle”, family Anacardiaceae, a native of South America, produces an active antibacterial essential oil extracted from the leaves and fruits. This work reports a complete study of its chemical composition and determines the antibacterial activity of Schinus molle L. essential oil and its main components. The results showed that the crude extract essential oil has a potent antibacterial effect on Staphylococcus aureus ATCC 25923, a strong/moderate effect on Escherichia coli ATCC 25922 and moderate/weak one on Pseudomonas aeruginosa ATCC 27853.

  10. Antibacterial activities of Emblica officinalis and Coriandrum sativum against Gram negative urinary pathogens.

    Science.gov (United States)

    Saeed, Sabahat; Tariq, Perween

    2007-01-01

    Present investigation is focused on antibacterial potential of aqueous infusions and aqueous decoctions of Emblica officinalis (amla) and Coriandrum sativum (coriander) against 345 bacterial isolates belonging to 6 different genera of Gram negative bacterial population isolated from urine specimens by employing well diffusion technique. Aqueous infusion and decoction of Emblica officinalis exhibited potent antibacterial activity against Escherichia coli (270), Klebsiella pneumoniae (51), K. ozaenae (3), Proteus mirabilis (5), Pseudomonas aeruginosa (10), Salmonella typhi (1), S. paratyphi A (2), S. paratyphi B (1) and Serratia marcescens (2) but did not show any antibacterial activity against Gram negative urinary pathogens.

  11. Synthesis and antibacterial activity screening of quaternary ammonium derivatives of triazolyl pyranochromenones

    Indian Academy of Sciences (India)

    PREETI YADAV; BIPUL KUMAR; HEMANT K GAUTAM; SUNIL K SHARMA

    2017-02-01

    A series of quaternary ammonium derivatives of triazolyl pyranochromen-2-ones have been synthesized and characterized; their antibacterial potential were investigated against two gram negative (Pseudomonas aeruginosa and Escherichia coli) and two gram positive bacterial strains (Bacillus cereus and Staphylococcus aureus). In order to develop structure-activity relationship (SAR), the effect of varying the substituent (R) at the C-10 position of pyranochromen-2-one as well as the length of the spacer (n) between the triazolyl pyranochromen-2-ones and quaternary ammonium group, on the antibacterial activity of compoundshas been evaluated. Some of the screened compounds exhibited antibacterial potential against the studied strains in the microgram range.

  12. A Study on the Antibacterial Activity Of Zno Nanoparticles Prepared By Combustion Method against E Coli

    OpenAIRE

    2014-01-01

    Crystalline Zinc Oxide (ZnO) nanoparticles were synthesized by low temperature solution combustion method using Oxalyl dihydrazide (ODH) as fuel, at much lower temperature (300oC). X-ray diffraction (XRD) confirmed the formation of wurtzite-structured pure ZnO No peaks from any else phases of ZnO and no impurity peaks were observed, indicating the high purity of the obtained hexagonal ZnO nanocrystals. The antibacterial activity of the formed nano ZnO were investigated against...

  13. Synthesis, characterization and in vitro antibacterial activity of novel phthalazine sulfonamide derivatives

    Indian Academy of Sciences (India)

    MARZIEH ABBASI; SEYED MOHAMAD REZA NAZIFI; ZAHRA SADAT NAZIFI; AHMAD REZA MASSAH

    2017-08-01

    Several phthalazine derivatives were synthesized by the one-pot three-component condensation in good to high yields in the presence of diatomite-SO3H as a solid acid catalyst. Then, a series (n=14) of phthalazine sulfonamides were synthesized by the reaction phthalazine sulfonyl chloride and various amines under solvent-free conditions. The prepared compounds were screened for antibacterial activity against Escherichia coli (E. coli ATCC 25922) and Staphylococcus aureus (S. aureus ATCC 5213) as gram negative and positive respectively. Also, in silico physicochemical parameters of synthesized compounds were studied to predict absorption and permeability using Molinspiration online property calculation server.

  14. Fatty acid composition, antioxidant and antibacterial activities of Adonis wolgensis L. extract.

    Science.gov (United States)

    Mohadjerani, Maryam; Tavakoli, Rahmatollah; Hosseinzadeh, Rahman

    2014-01-01

    The objective of this study was to analyze the fatty acid content, antioxidant, and antibacterial activities of hydro-methanolic extract of Adonis wolgensis L. (A. wolgensis L.) growing wild in north of Iran. Oils of A. wolgensis L. was obtained by means of Soxhlet apparatus from leaves and stems. Methyl esters were derived from the oily mixtures by trans-esterification process and were analyzed by GC/FID and GC/MS systems. Phenolic compounds extraction was done with aqueous methanol (90%). This extract was investigated for antioxidant activity using DPPH radical scavenging and reducing power methods and was also tested against a panel of microorganisms. Linolenic acid (45.83%) and oleic acid (47.54%) were the most abundant fatty acids in leaves and stems, respectively. Hydro-methanolic extract with the high amount of total phenolics (9.20 ±0.011 mg GAE per dry matter) was the potent antioxidant in the assays. RESULTS obtained from measurements of MIC for extract, indicated that E. coli, S. aureus, and S. enteritidis were the most sensitive microorganisms tested, but no activity was observed against Gram-positive microorganism (B. subtilis). The results obtained from the present study indicated that the oil of A. wolgensis leaves and stems contained a high source of poly-unsaturated fatty acids (PUFAs). These results also showed that hydro-methanolic extract of this plant contained significant antioxidant and antibacterial activities.

  15. Fatty acid composition, antioxidant and antibacterial activities of Adonis wolgensis L. extract

    Directory of Open Access Journals (Sweden)

    Maryam Mohadjerani

    2014-01-01

    Full Text Available Objectives: The objective of this study was to analyze the fatty acid content, antioxidant, and antibacterial activities of hydro-methanolic extract of Adonis wolgensis L. (A. wolgensis L. growing wild in north of Iran. Materials and Methods: Oils of A. wolgensis L. was obtained by means of Soxhlet apparatus from leaves and stems. Methyl esters were derived from the oily mixtures by trans-esterification process and were analyzed by GC/FID and GC/MS systems. Phenolic compounds extraction was done with aqueous methanol (90%. This extract was investigated for antioxidant activity using DPPH radical scavenging and reducing power methods and was also tested against a panel of microorganisms. Results: Linolenic acid (45.83% and oleic acid (47.54% were the most abundant fatty acids in leaves and stems, respectively. Hydro-methanolic extract with the high amount of total phenolics (9.20 ±0.011 mg GAE per dry matter was the potent antioxidant in the assays. Results obtained from measurements of MIC for extract, indicated that E. coli, S. aureus, and S. enteritidis were the most sensitive microorganisms tested, but no activity was observed against Gram-positive microorganism (B. subtilis. Conclusion: The results obtained from the present study indicated that the oil of A. wolgensis leaves and stems contained a high source of poly-unsaturated fatty acids (PUFAs. These results also showed that hydro-methanolic extract of this plant contained significant antioxidant and antibacterial activities.  

  16. Nanostructured composite material graphite/TiO2 and its antibacterial activity under visible light irradiation.

    Science.gov (United States)

    Dědková, Kateřina; Lang, Jaroslav; Matějová, Kateřina; Peikertová, Pavlína; Holešinský, Jan; Vodárek, Vlastimil; Kukutschová, Jana

    2015-08-01

    The paper addresses laboratory preparation, characterization and in vitro evaluation of antibacterial activity of graphite/TiO2 nanocomposites. Composites graphite/TiO2 with various ratio of TiO2 nanoparticles (30wt.%, and 50wt.%) to graphite were prepared using a thermal hydrolysis of titanylsulfate in the presence of graphite particles, and subsequently dried at 80°C. X-ray powder diffraction, transmission electron microscopy and Raman microspectroscopy served as phase-analytical methods distinguishing anatase and rutile phases in the prepared composites. Scanning and transmission electron microscopy techniques were used for characterization of morphology of the prepared samples. A developed modification of the standard microdilution test was used for in vitro evaluation of daylight induced antibacterial activity, using four common human pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis and Pseudomonas aeruginosa). Antibacterial activity of the graphite/TiO2 nanocomposites could be based mainly on photocatalytic reaction with subsequent potential interaction of reactive oxygen species with bacterial cells. During the antibacterial activity experiments, the graphite/TiO2 nanocomposites exhibited antibacterial activity, where differences in the onset of activity and activity against bacterial strains were observed. The highest antibacterial activity evaluated as minimum inhibitory concentration was observed against P. aeruginosa after 180min of irradiation. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. pH-Dependent metal ion toxicity influences the antibacterial activity of two natural mineral mixtures.

    Directory of Open Access Journals (Sweden)

    Tanya M Cunningham

    Full Text Available BACKGROUND: Recent studies have demonstrated that several mineral products sold for medicinal purposes demonstrate antimicrobial activity, but little is known about the physicochemical properties involved in antibacterial activity. METHODOLOGY/PRINCIPAL FINDINGS: Using in vitro mineral suspension testing, we have identified two natural mineral mixtures, arbitrarily designated BY07 and CB07, with antibacterial activity against a broad-spectrum of bacterial pathogens. Mineral-derived aqueous leachates also exhibited antibacterial activity, revealing that chemical, not physical, mineral characteristics were responsible for the observed activity. The chemical properties essential for bactericidal activity against Escherichia coli were probed by testing antibacterial activity in the presence of metal chelators, the hydroxyl radical scavenger, thiourea, and varying pH levels. Chelation of the BY07 minerals with EDTA or desferrioxamine eliminated or reduced BY07 toxicity, respectively, suggesting a role of an acid-soluble metal species, particularly Fe(3+ or other sequestered metal cations, in mineral toxicity. This conclusion was supported by NMR relaxation data, which indicated that BY07 and CB07 leachates contained higher concentrations of chemically accessible metal ions than leachates from non-bactericidal mineral samples. CONCLUSIONS/SIGNIFICANCE: We conclude that the acidic environment of the hydrated minerals significantly contributes to antibacterial activity by increasing the availability and toxicity of metal ions. These findings provide impetus for further investigation of the physiological effects of mineral products and their applications in complementary antibacterial therapies.

  18. Bacillus spp. produce antibacterial activities against lactic acid bacteria that contaminate fuel ethanol plants

    Science.gov (United States)

    Lactic acid bacteria (LAB) frequently contaminate commercial fuel ethanol fermentations, reducing yields and decreasing profitability of biofuel production. Microorganisms from environmental sources in different geographic regions of Thailand were tested for antibacterial activity against LAB. Fou...

  19. Antibacterial activity of lichen Usnea rubrotincta, Ramalina dumeticola, and Cladonia verticillata

    Science.gov (United States)

    Gunasekaran, Saranyapiriya; Rajan, Vinoshene Pillai; Samsudin, Mohd. Wahid; Din, Laily; Ramanathan, Surash; Murugaiyah, Vikneswaran

    2015-09-01

    The present study was carried out to evaluate the antibacterial activity of extract and chemical constituents of Usnea rubrotincta, Ramalina dumeticola and Cladonia verticillata. Extracts of U. rubrotincta and R. dumeticola showed promising antibacterial activity against gram positive bacteria Staphylococcus aureus and Bacillus subtilis. The lowest value of MIC (15.63 μg/mL) was observed for the acetone extract of U. rubrotincta against B. subtilis. While extract of C. verticillata was neither active against gram positive nor gram negative bacteria at the highest tested concentration of 500 μg/m. This is the first evaluation of antibacterial activity of lichens found in Malaysia and to our knowledge, this is the first report of antibacterial

  20. Antibacterial Activity of 2- (2',4'- Dibromophenoxy) -4, 6 - dibromophenol from Dysidea granulose

    Digital Repository Service at National Institute of Oceanography (India)

    DivyaShridhar, M.P.; Mahajan, G.B.; Kamat, V.P.; Naik, C.G.; Parab, R.R.; Thakur, N.R.; Mishra, P.D.

    2 - (2',4'- Dibromophenoxy) - 4, 6 - dibromophenol isolated from the marine sponge Dysidea granulosa (Bergquist) collected off the coast of Lakshadweep islands, Indian Ocean, exhibited potent and broad spectrum in-vitro antibacterial activity...

  1. Antibacterial activity of the sponge Ircinia ramosa: Importance of its surface-associated bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Thakur, N.L.; Anil, A.C.

    Variations in the antibacterial activity of the sponge Ircinia ramosa were evaluated during two collection periods (January and May) against vicinity fouling bacteria (VFB) and sponge surface-associated bacteria (SAB). The density of fouling...

  2. Chemical composition and antibacterial activity of essential oils against human pathogenic bacteria

    NARCIS (Netherlands)

    Sokovic, M.; Marin, P.D.; Brkic, D.; Griensven, van L.J.L.D.

    2008-01-01

    The chemical composition and antibacterial activity of essential oils from 10 aromatic plants Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angustifolia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium have been determined. Anti

  3. A New and Efficient Synthetic Method and Antibacterial Activities of Oxazolidinone Analogues

    Institute of Scientific and Technical Information of China (English)

    De Sheng YU; Liang HUANG; Hui LIANG; Ping GONG

    2005-01-01

    A series of novel oxazolidinone analogues were prepared by a new and efficient synthetic method and their antibacterial activities were determined. These compounds were characterized by LC-MS and 1H NMR.

  4. Chemical composition and antibacterial activity of essential oils from different parts of Leonurus japonicus Houtt.

    Science.gov (United States)

    Xiong, Liang; Peng, Cheng; Zhou, Qin-Mei; Wan, Feng; Xie, Xiao-Fang; Guo, Li; Li, Xiao-Hong; He, Cheng-Jun; Dai, Ou

    2013-01-14

    The herb and fruits of Leonurus japonicus Houtt., named "Yimucao" and "Chongweizi", respectively, in Chinese, have been widely used in China as gynecological medicines. The components of the essential oils obtained by hydrodistillation were investigated by GC-MS. The antibacterial activity of the essential oils was determined by micro-dilution assay. The results showed large variations in the chemical composition and antibacterial activity of the oils. The oil of "Yimucao" showed antibacterial activity against various Gram-positive bacteria and consisted mainly of sesquiterpenes and diterpenes, with phytone, phytol, caryophyllene oxide and β-caryophyllene being the most significant constituents, whereas the oil of "Chongweizi", mainly made up of bornyl acetate and aliphatic hydrocarbons, was inactive in the antibacterial assay. Further study of the main compounds in "Yimucao oil" showed that β-caryophyllene had wide-spectrum activity against Gram-positive bacteria.

  5. Evaluation of anti-bacterial and wound healing activity of the fruits of ...

    African Journals Online (AJOL)

    Evaluation of anti-bacterial and wound healing activity of the fruits of ... the functional roles of the fruits of Amorpha fruticosa L. during wound healing progress. ... fibroblasts proliferation and migration, leading to promotion of wound healing.

  6. Preparation and antibacterial activity of chitosan microshperes in a solid dispersing system

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this study,we investigated the interface contacting inhibition behaviors of chitosan against bacterial in the dispersing state.For that purpose,chitosan microspheres (CMs) in the dispersing state was prepared by the emulsification cross-linking method.The CMs had smooth surface and spherical shape with the diameter of about 124 μm.They were stable after sterilization at 121℃ and 150 kPa for 20 min.The CMs had similar antibacterial activity to that of chitosan in the solution form.Their antibacterial activities increased with the increase of the CM concentration,while decreased with the increase of pH of the system.It was found that the CMs with the degree of deacetylation (DD) of 63.6% exhibited the highest antibacterial activity,while the CMs with the DD of 83.7% exerted the lowest antibacterial activity among the three tested samples.

  7. Screening of antibacterial activity of raspberry (Rubus idaeus L. fruit and pomace extracts

    Directory of Open Access Journals (Sweden)

    Velićanski Aleksandra S.

    2012-01-01

    Full Text Available Antibacterial activity of fruit and pomace extracts (concentration 50 mg/ml of two raspberry (Rubus idaeus L. cultivars (Meeker and Willamette was tested against selected Gram-positive and Gram-negative bacteria (reference and wild strains. Disc diffusion method with 15 μl of extracts and agar-well diffusion method with 50 and 100 μl were used. Antibiotic (cefotaxime/clavulanic acid was used as a control. Both raspberry fruit extracts showed the strongest antibacterial activity against Pseudomonas aeruginosa (wild strain and Bacillus cereus, where the largest clear zones (without growth appeared. Escherichia coli was the most resistant strain, with only zone of reduced growth. The highest antibacterial activity of pomace extracts was against Staphylococcus aureus and Staphylococcus saprophyticus. There were no differences in the antibacterial activity between cultivars for both fruit and pomace extracts. [Projekat Ministarstva nauke Republike Srbije, br. TR 31044

  8. Chemical composition and antibacterial activity of essential oils against human pathogenic bacteria

    NARCIS (Netherlands)

    Sokovic, M.; Marin, P.D.; Brkic, D.; Griensven, van L.J.L.D.

    2008-01-01

    The chemical composition and antibacterial activity of essential oils from 10 aromatic plants Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angustifolia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium have been determined.

  9. Antibacterial, antifungal and insecticidal activities of some selected medicinal plants of polygonaceae

    National Research Council Canada - National Science Library

    Farrukh Hussain; Bashir Ahmad; Ishfaq Hameed; Ghulam Dastagir; Parveen Sanaullah; Sadiq Azam

    2010-01-01

      The antibacterial, antifungal and insecticidal activities of the crude extract ofPolygonum persicaria , Rumex hastatus , Rumex dentatus , Rumex nepalensis ,Polygonum plebejum and Rheum australe have been studied...

  10. EFFECT OF COPPER IMPLANTATION ON ANTIBACTERIAL ACTIVITY OF AUSTENITIC STAINLESS STEEL

    Institute of Scientific and Technical Information of China (English)

    J. Xiong; B.F. Xu; H.W. Ni; P.Y. Xiong; Z.G. Dan

    2004-01-01

    Antibacterial activity has been studied by copper ion implantation into 0Cr18Ni9 stainless steel.Ions extracted from a metal vapor vacuum arc (MEWA) are sourced with 60-100keV energy and a dose range (0.2-2.0)×1017 ions cm-2. Saturation doses, surface concentration were calculated and the relationships between energy, dose and antibacterial activity were analyzed.Novel phases such as Fe4Cu3 and Cu0.81Ni0-19 were found after copper implantation by X-ray diffraction. The novel phases effects on antibacterial activity have been investigated. The results show that saturation dose varies with the ions′energy. Antibacterial activity has close relation with copper's concentration in implanted layer and Cu-rich phase.

  11. Investigation of Anti-bacterial Activity against Food-borne Pathogens among Korean Domestic Algae

    Directory of Open Access Journals (Sweden)

    Ki-hyo Jang

    2015-03-01

    Full Text Available The aim of this study is to explore algal species with anti-bacterial activity against six food-borne pathogens. Among 51 marine algae, Laurencia okamurae Yamada and Dictyopteris undulata Holmes was elucidated to have a potent anti-bacterial activity against food-borne pathogens. Laurencia okamurae Yamada showed the clear zone around agar well on B. cereus, S. aureusand L. monocytogenes-spreading agar plate. Dictyopteris undulata Holmes had the anti-bacterial activity against S. chorelaesuis, B. cereus, S. aureus and L. monocytogenes on bacterial spreading agar plates. Antibacterial activity of L. okamurae Yamada and D. undulata Holmes had specifically susceptibility for B. cereus, S. aureus and L. monocytogenes and were superior to streptomycin, the authentic antibiotics. It is anticipated that new food preservatives can be explored and developed on the basis of this study.

  12. Study of the antibacterial and antifungal activities of synthetic benzyl bromides, ketones, and corresponding chalcone derivatives

    Science.gov (United States)

    Shakhatreh, Muhamad Ali K; Al-Smadi, Mousa L; Khabour, Omar F; Shuaibu, Fatima A; Hussein, Emad I; Alzoubi, Karem H

    2016-01-01

    Several applications of chalcones and their derivatives encouraged researchers to increase their synthesis as an alternative for the treatment of pathogenic bacterial and fungal infections. In the present study, chalcone derivatives were synthesized through cross aldol condensation reaction between 4-(N,N-dimethylamino)benzaldehyde and multiarm aromatic ketones. The multiarm aromatic ketones were synthesized through nucleophilic substitution reaction between 4-hydroxy acetophenone and benzyl bromides. The benzyl bromides, multiarm aromatic ketones, and corresponding chalcone derivatives were evaluated for their activities against eleven clinical pathogenic Gram-positive, Gram-negative bacteria, and three pathogenic fungi by the disk diffusion method. The minimum inhibitory concentration was determined by the microbroth dilution technique. The results of the present study demonstrated that benzyl bromide derivatives have strong antibacterial and antifungal properties as compared to synthetic chalcone derivatives and ketones. Benzyl bromides (1a and 1c) showed high ester activity against Gram-positive bacteria and fungi but moderate activity against Gram-negative bacteria. Therefore, these compounds may be considered as good antibacterial and antifungal drug discovery. However, substituted ketones (2a–b) as well as chalcone derivatives (3a–c) showed no activity against all the tested strains except for ketone (2c), which showed moderate activity against Candida albicans. PMID:27877017

  13. Antibacterial activity against Clostridium genus and antiradical activity of the essential oils from different origin.

    Science.gov (United States)

    Kačániová, Miroslava; Vukovič, Nenad; Horská, Elena; Salamon, Ivan; Bobková, Alica; Hleba, Lukáš; Fiskelová, Martina; Vatľák, Alexander; Petrová, Jana; Bobko, Marek

    2014-01-01

    In the present study, the antimicrobial and antiradical activities of 15 essential oils were investigated. The antimicrobial activities were determined by using agar disc diffusion and broth microdilution methods against Clostridium genus and antioxidant properties of essential oils by testing their scavenging effect on DPPH radicals activities. We determined the antibacterial activity of Clostridium butyricum, Clostridium hystoliticum, Clostridium intestinale, Clostridium perfringens and Clostridium ramosum. We obtained the original commercial essential oils samples of Lavandula angustifolia, Carum carvi, Pinus montana, Mentha piperita, Foeniculum vulgare Mill., Pinus sylvestris, Satureia montana, Origanum vulgare L. (2 samples), Pimpinella anisum, Rosmarinus officinalis L., Salvia officinalis L., Abies alba Mill., Chamomilla recutita L. Rausch and Thymus vulgaris L. produced in Slovakia (Calendula a.s., Nova Lubovna, Slovakia). The results of the disk diffusion method showed very high essential oils activity against all tested strains of microorganisms. The best antimicrobial activity against C. butyricum was found at Pimpinella anisum, against C. hystoliticum was found at Pinus sylvestris, against C. intestinale was found at Satureia hortensis L., against C. perfringens was found at Origanum vulgare L. and against C. ramosum was found at Pinus sylvestris. The results of broth microdilution assay showed that none of the essential oils was active against C. hystoliticum. The best antimicrobial activity against C. butyricum was found at Abies alba Mill., against C. intestinale was found at Abies alba Mill., against C. perfringens was found at Satureia montana and against C. ramosum was found at Abius alba and Carum carvi. Antioxidant DPPH radical scavenging activity was determined at several solutions of oil samples (50 μL.mL(-1)-0.39 μL.mL(-1)) and the best scavenging effect for the highest concentration (50 μL.mL(-1)) was observed. The antioxidant properties

  14. Antibacterial activity of starfish Stellaster equestris from Southeast Coast of India

    Institute of Scientific and Technical Information of China (English)

    Kolandhasamy Prabhu; Subramanian Bragadeeswaran

    2013-01-01

    Objective: To isolate and characterize the antibacterial compounds from starfish Stellaster equestris (S. equestris).Methods:The whole body was extracted with high polar and medium polar solvents such as methanol and ethanol. The antibacterial activity has been tested against human bacterial pathogens using standard disc diffusion method.Results:The starfish S. equestris was collected from Mudasalodai, southeast coast of India. the maximum zone inhibition [(9.7±0.3) mm] against Escherichia coli (E. coli) and Vibrioparahaemolyticus at 100% concentration and minimum was Staphylococcus aureus [(4.0±0.6) mm]. The crude ethanol extract showed maximum zone of inhibition in E. coli [(9.70±0.33) mm] and the lowest concentration exhibited the minimum inhibition activity against all bacterial pathogens. The fractions showed the maximum inhibition zone in Klebsiella oxytoca (5.00±0.82 mm), Salmonella typhi (S. typhi) (5.00±0.82) and Staphylococcus aureus [(3.0±2.3) mm]. One way ANOVA analysis of antibacterial activity showed no significant difference at 0.05% level (P>0.05). The crude ethanol extract showed the minimum inhibitory concentration against E. coli (100%),Klebsiella pneumoniae The present investigation exhibited that the crude methanol extract showed the minimum inhibitory concentration against Klebsiella pneumonia, Proteus mirabilis, S. typhi,Staphylococcus aureus and Vibrio cholerae at 100% whereas E. coli was at 75% concentration. No bacterial growth was observed against Klebsiella oxytoca at 100% concentration.Conclusions:(75%), S. typhi (100%) and Vibrio cholerae (100%). The fraction exhibited equestris have remarkable antimicrobial activities against human bacterial pathogens. Further fraction has been characterised by using GC-MS and 1H and 13NMR spectroscopy analysis. The result of the present study indicates that the crude and fractions of starfish S.

  15. Antioxidant and antibacterial activities of vegetables and fruits commonly consumed in Thailand.

    Science.gov (United States)

    Rattanasena, Paweena

    2012-09-15

    The vegetables and fruits commonly consumed in Thailand have been suggested as rich sources of beneficial phytochemicals. In this study, vegetables and fruits native to the Northeast region of Thailand were evaluated for antioxidant and antibacterial activities. For vegetables, the extracts of Limnophila aromatica (Lamk.) Merr. (extracted by 80% ethanol) and Sauropus androgynus (Linn.) Merr. (extracted by distilled water) were found to have significant levels of antioxidant activities measured by DPPH scavenging (IC5o at 4.92+/-0.01 and 4.71+/-0.01 mg mL-1, respectively) and FRAP antioxidant assays (74.38+/-0.25 and 74.00+/-0.04 mmol FeSO4 g-' of dry weight of vegetable, respectively) and also total phenolic compounds (10.96+/-0.02 and 10.34+/-0.01 mg gallic acid eq g-1 of dry weight of vegetable). For fruits, the extracts derived from Terminalia chebula Retz. when using distilled water and 80% ethanol as solvents were shown to have significantly high levels of DPPH scavenging (IC50 at 3.73+/-0.01 and 3.81+/-0.01 mg mL-1, respectively), FRAP antioxidant activities (80.85+/-0.10 and 65.93+/-0.11 mmol FeSO4 g-1of dry weight of fruit, respectively) and total phenolic compounds (13.10+/-0.06 and 10.66+/-0.02 mg gallic acid eq g-1 of dry weight of fruit, respectively). The antibacterial assays showed that Moringa oleifera Lam., Limnophila aromatica (Lamk.) Merr., Terminalia chebula Retz. and Phyllanthus emblica Linn. that were extracted using 80% ethanol as solvent were found to have antibacterial activities against Staphylococcus aureus, Straphylococcus epidermidis, Streptococcus pyogenes and Propionibacterium acnes. The results in this study may be useful for future application of edible plants that are native to Thailand to be used as cosmetic or therapqutic products.

  16. Comparison of Antioxidant and Antibacterial Activities of Free and Encapsulated Garlic Oil with Beta-cyclodextrin

    OpenAIRE

    2016-01-01

    Background and Objectives: Application of garlic oil in food industry can be improved by encapsulation. There is no study about the formation of inclusion complex of garlic oil by beta-cyclodextrin. The aim of the present study is comparison of the antioxidant and antibacterial activities of free and encapsulated garlic oil with beta-cyclodextrin.Materials and Methods: Antioxidant activity was determined by 1, 1- diphenyl-2- picryl-hydrazyl assay, and antibacterial properties by agar well dif...

  17. EVALUATION OF PHYTOCHEMICAL AND ANTIBACTERIAL ACTIVITY OF PEDALIUM MUREX LINN. ROOT

    Directory of Open Access Journals (Sweden)

    Muruganantham Sermakkani

    2011-03-01

    Full Text Available In the present study, the Petroleum ether, Chloroform, Acetone and Methanolic extract of Pedalium murex L. root was subjected to preliminary phytochemical compounds and antibacterial activity of certain human pathogenic microorganisms. The extracts indicated the presence of flavonoids, glycosides, steroids, phenols, alkaloids and tannins. Maximum antibacterial activity was observed in methanolic extract against gram positive bacteria, Streptococcus pyogenes and Enterococcus faecalis than the gram negative bacteria.

  18. Antibacterial activity of some medicinal mangroves against antibiotic resistant pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Abeysinghe P

    2010-01-01

    Full Text Available The antibacterial activity of the leaves and bark of mangrove plants, Avicennia marina, A. officinalis, Bruguiera sexangula, Exoecaria agallocha, Lumnitzera racemosa, and Rhizophora apiculata was evaluated against antibiotic resistant pathogenic bacteria, Staphylococcus aureus and Proteus sp. Soxhlet extracts of petroleum ether, ethyl acetate, ethanol and water were prepared and evaluated the antibacterial activity using agar diffusion method. Most of the plant extracts showed promising antibacterial activity against both bacterial species. However, higher antibacterial activity was observed for Staphylococcus aureus than Proteus sp. The highest antibacterial activity was shown by ethyl acetate of mature leaf extracts of E. agallocha for Staphylococcus aureus. All ethyl acetate extracts showed higher inhibition against S. aureus while some extracts of chloroform, ethyl acetate and ethanol gave inhibition against Proteus sp. None of the petroleum ether and aqueous extracts showed inhibition against Proteus sp. All fresh plant materials did also show more antibacterial activity against both bacterial strains than did dried plant extracts. Antibacterial activity of fresh and dried plant materials reduced for both bacterial strains with time after extraction. Since L. racemosa and A. marina gave the best inhibition for bacterial species, they were used for further investigations. Charcoal treated plant extracts of L. racemosa and A. marina were able to inhibit both bacterial strains more than those of untreated plant extracts. Phytochemical screening of mature leaf, bark of L. racemosa and leaf extracts of A. marina has been carried out and revealed that leaf and bark contained alkaloids, steroids, triterpenoids and flavonoids. None of the above extracts indicate the presence of saponins and cardiac glycosides. Separated bands of extracts by TLC analysis showed antibacterial activity against S. aureus.

  19. In vitro antibacterial activity of selected medicinal plants traditionally used in Vietnam against human pathogenic bacteria

    OpenAIRE

    Vu, Thuy Thu; Kim, Hyungrok; Tran, Vu Khac; Le Dang, Quang; Nguyen, Hoa Thi; Kim, Hun; Kim, In Seon; Choi, Gyung Ja; Kim, Jin-Cheol

    2016-01-01

    Background Medicinal plants are widely used for the treatment of different infectious diseases. Infectious diseases caused by bacteria have a large impact on public health. This study aimed to determine the in vitro antibacterial activity of the medicinal plants traditionally used in Vietnam against the bacterial strains associated with infectious diseases. Methods Methanol extracts of twelve Vietnamese medicinal plants were tested for their antibacterial activity against five bacterial speci...

  20. Antioxidant and antibacterial activities of various extracts of Inula cuspidata C.B. Clarke stem

    Directory of Open Access Journals (Sweden)

    Sarvesh Kumar Paliwal

    2017-06-01

    All the extracts showed significant antibacterial activities against Gram positive bacterial strains with minimum inhibitory concentration (MIC values ranging from 187.5 to 750 µg/mL and moderate to weak inhibition against Gram negative bacteria with MIC values ranging from 750 to 3000 µg/mL. The present study proves the in vitro anti-oxidant and antibacterial activities of different extracts of I. cuspidata stem.

  1. Comparison of Antioxidant and Antibacterial Activities of Free and Encapsulated Garlic Oil with Beta-cyclodextrin

    OpenAIRE

    Khadijeh Khoshtinat; Mohsen Barzegar; Mohammad Ali Sahari; Zohreh Hamidi

    2016-01-01

    Background and Objectives: Application of garlic oil in food industry can be improved by encapsulation. There is no study about the formation of inclusion complex of garlic oil by beta-cyclodextrin. The aim of the present study is comparison of the antioxidant and antibacterial activities of free and encapsulated garlic oil with beta-cyclodextrin.Materials and Methods: Antioxidant activity was determined by 1, 1- diphenyl-2- picryl-hydrazyl assay, and antibacterial properties by agar well dif...

  2. Antibacterial activity of rhizome of curcuma aromatica and partial purification of active compounds

    OpenAIRE

    S. Revathi; Malathy, N.S.

    2013-01-01

    The hexane extract of Curcuma aromatica, a plant belonging to the family Zingiberaceae was tested on 10 bacterial strains (clinical isolates and standard strains). Agar diffusion method was adopted for determining the antibacterial activity of the extract. The hexane extract was found to be active against all Gram-positive strains tested, but inactive against Gram-negative strains. The minimum inhibitory concentration and minimum bactericidal concentration were determined and found to be 539 ...

  3. Antibacterial and Anticandidal Activities of Common Essential Oil Constituents

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    Gökalp İşcan

    2017-07-01

    Full Text Available Essential oils and some of their oxygenated constituents are known to possess antimicrobial activity. In the last 30 years, there is a dramatic increase in the number of resistant microorganisms against available antimicrobials and a tendency towards natural products; consequently, scientists have been forced to discover new bioactive agents preferably from nature. As a result of this, so many antimicrobial screening works have been published on plant essential oils including miscellaneous screening methods and several microorganism strains. The aim of this study was to determine the MIC values of 65 monoterpenoids and 3 phenyl propanoids commonly found in essential oils, against 24 pathogenic bacteria and Candida strains, by using standard reference broth dilution methods (CLSI M7-A7 and M27-A2. According to broth microdilution test results, when compared with standard agents, monoterpene hydrocarbons generally showed weak antibacterial effects (>16 to 4 mg/mL where the oxygenated monoterpenes inhibited the microbial growth between the concentrations of 16 to 0,03 mg/mL. Generally, tested compounds demonstrated better inhibitory effects on Candida strains then the bacteria panel. The most effective microbial growth inhibitor constituents were determined as carvacrol, thymol, cumin alcohol, terpinen-4-ol, α-terpineol, lavandulol, estragol and thymoquinone.

  4. Ammonia sensor and antibacterial activities of green zinc oxide nanoparticles

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    S. Khaleel Basha

    2016-09-01

    Full Text Available Zinc oxide nanoparticles was synthesized by alginate (A through a rapid and a facile step in the aqueous solution condition at room temperature. Fabrication of zinc oxide nanoparticles was characterized by ATR-FTIR, TEM and XRD. ATR-FTIR analysis confirmed that the A/ZnO NPs were encapsulated by the polymerized alginate. Their shape, structure and composition were assessed by SEM. TEM and XRD analysis indicated that the A/ZnO NPs give evidence of the crystalline nature of ZnO and hybrid NPs structure, which is suitable for ammonia gas sensor development. The controlled size of the A/ZnO NPs obtained using this innovative synthesis strategy minimizes the response time of 2–3 s to sense the ammonia gas significantly with a detection limit of 1 ppm were found at room temperature. The antibacterial tests revealed that the A/ZnO NPs exhibits a potent activity against gram positive and gram negative bacteria.

  5. Phytochemical Composition and Antibacterial Activity of Hydroalcoholic Extracts of Pterospartum tridentatum and Mentha pulegium against Staphylococcus aureus Isolates

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    Alfredo Aires

    2016-01-01

    Full Text Available Pterospartum tridentatum and Mentha pulegium are largely used in Portuguese folk medicine to treat several human disorders and inflammatory processes but without any consistent evidence for those beneficial pointed properties. Thus, the aim of the current work is to evaluate its benefits and phytochemicals related to those beneficial properties. A distinct polyphenol profile between P. tridentatum and M. pulegium was found. Taxifolin, myricetin, ginestin, ginestein, and ginestein derivatives, biochanin A-glucoside, and biochanin A were identified in P. tridentatum, whilst in M. pulegium the luteolin-7-rutinoside, diosmin, and apigenin and respective derivatives were most representative polyphenols. These variations had implications in the antiradical and antibacterial activity and the P. tridentatum exhibited the highest antibacterial activity against methicillin-resistant and methicillin-sensitive Staphylococcus aureus MSSA, which was mainly dose-dependent. This antibacterial activity seems to be related to high content of flavonols, flavones, and isoflavones, which can act synergistically with each other against this type of bacteria. Our results showed consistent evidence that Pterospartum tridentatum and Mentha pulegium are an important reservoir of phytochemicals with antiradical activity and antibacterial capacity and thus they might be used in a preventive way or in a combined pharmaceutical and antibiotic therapy against pathogenic bacteria.

  6. Phytochemical Composition and Antibacterial Activity of Hydroalcoholic Extracts of Pterospartum tridentatum and Mentha pulegium against Staphylococcus aureus Isolates.

    Science.gov (United States)

    Aires, Alfredo; Marrinhas, Eduardo; Carvalho, Rosa; Dias, Carla; Saavedra, Maria José

    2016-01-01

    Pterospartum tridentatum and Mentha pulegium are largely used in Portuguese folk medicine to treat several human disorders and inflammatory processes but without any consistent evidence for those beneficial pointed properties. Thus, the aim of the current work is to evaluate its benefits and phytochemicals related to those beneficial properties. A distinct polyphenol profile between P. tridentatum and M. pulegium was found. Taxifolin, myricetin, ginestin, ginestein, and ginestein derivatives, biochanin A-glucoside, and biochanin A were identified in P. tridentatum, whilst in M. pulegium the luteolin-7-rutinoside, diosmin, and apigenin and respective derivatives were most representative polyphenols. These variations had implications in the antiradical and antibacterial activity and the P. tridentatum exhibited the highest antibacterial activity against methicillin-resistant and methicillin-sensitive Staphylococcus aureus MSSA, which was mainly dose-dependent. This antibacterial activity seems to be related to high content of flavonols, flavones, and isoflavones, which can act synergistically with each other against this type of bacteria. Our results showed consistent evidence that Pterospartum tridentatum and Mentha pulegium are an important reservoir of phytochemicals with antiradical activity and antibacterial capacity and thus they might be used in a preventive way or in a combined pharmaceutical and antibiotic therapy against pathogenic bacteria.

  7. Identification and antibacterial activity of methanol extract of Luffa acutangula Roxb.

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    Resmi Mustarichie

    2012-10-01

    Full Text Available Antibacterial activity of Luffa acutangula Roxb. (angled luffa has been assayed against some pathogenic bacterial. Fruit powder of angled luffa was macerated with methanol, and the methanol extract extracted sequentially with hexane, chloroform, ethyl acetate and buthanol. Antibacterial activity was evaluated by well diffusion method. Extract with the highest antibacterial activity was identified regarding their class of compounds using phytochemical screening and Thin Layer Chromatography (TLC method. The antibacterial activity of the extract was compared with that of the ampicillin used. The methanol extract inhibited the growth of the P. aeruginosa, E. Coli, B. Subtilis and S.aureus, but did not inhibit the growth of the E. Aerogenes, S. dysentriae and S. thypi. The ethyl acetate extract showed the highest antibacterial activity against P. aeruginosa, E. Coli, B. Subtilis and S. aureus, followed by chloroform, buthanol, and hexane extract, respectively. The ethyl acetate extract possed phenolic, condensed tannin, flavonoids, saponins and terpenoids. Based on the MIC and the equivalent value of ethyl acetate extract compared with that ampicillin used, the antibacterial activity of ethyl acetate extract was lower than with that of the ampicillin used.

  8. Antibacterial Activities and Mechanism of Action of Acetone Extracts from Rabdosia rubescens

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    Li Ping Cheng

    2014-12-01

    Full Text Available The antibacterial activities and mechanism of action of acetone extracts from R. rubescens were reported in this paper. The results showed that 80% acetone extracts had both the highest contents of total phenolics and flavonoids. Acetone extracts showed better antibacterial activities against Gram-positive bacterial strains and there were no inhibitory effects found on tested Gram-negative bacteria. In addition, 80% acetone extracts from R. rubescens had relatively higher antibacterial activities with the lowest values of MIC and MBC at 2.5 mg/mL and 5 mg/mL against B. subtilis. The antibacterial mechanism of 80% acetone extracts against Bacillus subtilis might be described as disrupting cell wall, increasing cell membrane permeability, and finally leading to the leakage of cell constituents

  9. Report: Studies on antibacterial activity of some traditional medicinal plants used in folk medicine.

    Science.gov (United States)

    Israr, Fozia; Hassan, Fouzia; Naqvi, Baqir Shyum; Azhar, Iqbal; Jabeen, Sabahat; Hasan, S M Farid

    2012-07-01

    Ethanolic extracts of eight medicinal plants commonly used in folk medicine were tested for their antibacterial activity against four Gram positive strains (Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis and, Streptococcus pneumoniae) and six Gram negative strains (Escherichia coli, Proteus vulgaris, Proteus mirabilis. Salmonella typhi para A, Salmonella typhi para B and Shigella dysenteriae) that were obtained from different pathological laboratories located in Karachi, Pakistan. Disc diffusion method was used to analyze antibacterial activity. Out of eight, five medicinal plants showed antibacterial activity against two or more than two microbial species. The most effective antimicrobial plant found to be Punica granatum followed by Curcuma zedoaria Rosc, Grewia asiatica L and Carissa carandas L, Curcuma caesia Roxb respectively. From these results, it is evident that medicinal plants could be used as a potential source of new antibacterial agents.

  10. In vitro antibacterial activity of theHertia cheirifolia L. essential oils

    Institute of Scientific and Technical Information of China (English)

    Kaouther Majouli; Malek Besbes Hlila; Guido Flamini; Hichem Ben Jannet; Abderraouf Kenani

    2016-01-01

    Objective:To investigate the antibacterial activity of essential oils fromHertia cheirifolia L. flowers, vegetative part (leaves + stems) and roots against a panel of bacterial strains. Methods:The essential oils fromHertia cheirifolia L. flowers, vegetative part (leaves + stems) and rootswere analyzed by gas chromatography and gas chromatography–mass spectrometry. The antibacterial activity of essential oils was evaluatedin vitro by the broth dilution method. Results:The results showed that the essential oil of flowers exhibited a strong antibacterial activity againstStaphylococcus aureus with minimal inhibitory concentration of 0.078 mg/mL. Conclusions:The essential oils ofHertia cheirifolia can be a good source of antibacterial compounds. They can be used for pharmaceutical treatments.

  11. Enhanced antibacterial activity of bimetallic gold-silver core-shell nanoparticles at low silver concentration

    Science.gov (United States)

    Banerjee, Madhuchanda; Sharma, Shilpa; Chattopadhyay, Arun; Ghosh, Siddhartha Sankar

    2011-12-01

    Herein we report the development of bimetallic Au@Ag core-shell nanoparticles (NPs) where gold nanoparticles (Au NPs) served as the seeds for continuous deposition of silver atoms on its surface. The core-shell structure and morphology were examined by UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD). The core-shell NPs showed antibacterial activity against both Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive (Enterococcus faecalis and Pediococcus acidilactici) bacteria at low concentration of silver present in the shell, with more efficacy against Gram negative bacteria. TEM and flow cytometric studies showed that the core-shell NPs attached to the bacterial surface and caused membrane damage leading to cell death. The enhanced antibacterial properties of Au@Ag core-shell NPs was possibly due to the more active silver atoms in the shell surrounding gold core due to high surface free energy of the surface Ag atoms owing to shell thinness in the bimetallic NP structure.Herein we report the development of bimetallic Au@Ag core-shell nanoparticles (NPs) where gold nanoparticles (Au NPs) served as the seeds for continuous deposition of silver atoms on its surface. The core-shell structure and morphology were examined by UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD). The core-shell NPs showed antibacterial activity against both Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive (Enterococcus faecalis and Pediococcus acidilactici) bacteria at low concentration of silver present in the shell, with more efficacy against Gram negative bacteria. TEM and flow cytometric studies showed that the core-shell NPs attached to the bacterial surface and caused membrane damage leading to cell death. The enhanced antibacterial properties of Au@Ag core-shell NPs was

  12. Antibacterial activity of rhizome of curcuma aromatica and partial purification of active compounds

    Directory of Open Access Journals (Sweden)

    S Revathi

    2013-01-01

    Full Text Available The hexane extract of Curcuma aromatica, a plant belonging to the family Zingiberaceae was tested on 10 bacterial strains (clinical isolates and standard strains. Agar diffusion method was adopted for determining the antibacterial activity of the extract. The hexane extract was found to be active against all Gram-positive strains tested, but inactive against Gram-negative strains. The minimum inhibitory concentration and minimum bactericidal concentration were determined and found to be 539 ΅g/ml. The phytochemical analysis of hexane extract by gas chromatography mass spectrometry revealed the presence of 13 compounds. The crude hexane extract was partially purified by thin layer chromatography. The zone showing good antibacterial activity was analysed further by gas chromatography mass spectrometry, UV/Vis spectrophotometry and Fourier transform infrared spectroscopy, which indicated the probable presence of germacrone.

  13. Evaluation of antibacterial activity of plant mediated CaO nanoparticles using Cissus quadrangularis extract.

    Science.gov (United States)

    Marquis, Gowdhami; Ramasamy, Balagurunathan; Banwarilal, Sarkar; Munusamy, Ayyasamy Pudukadu

    2016-02-01

    An assessment of antibacterial activity of greenly synthesized nanoparticles using aqueous stem extract of Cissus quadrangularis was carried out. The synthesized nanoparticles were characterized by UV-Vis spectroscopy, SEM, XRD, FTIR and further subjected for antibacterial activity against the pathogens Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella typhi, Shigella dysenteriae and Vibrio cholerae. The SEM photograph represents cubic and hexagonal shape of NPs about 58nm respectively whereas the XRD indicated the pure phase of the product and no impurity in peaks of well crystallized products. The FTIR spectrum of nanoparticles showed intensive peaks with blue shift indicating the crystalline and shorten the distance of crystal lattice. The plant mediated CaO nanoparticles showed maximum inhibition on E. coli followed by other strains. In MIC, the plant mediated CaO NPs possess high activity against all the test organisms whereas the CaCl2 and CaO compounds were moderately active. The approach to the synthesis of plant mediated CaO NPs has many advantages as scaled up, economic viability, etc. Application of such ecofriendly nanoparticles in bactericidal, wound healing and other medical applications makes this method potential existing for the large scale synthesis of the inorganic materials.

  14. Antibacterial activity and cytotoxicity of selected Egyptian medicinal plants.

    Science.gov (United States)

    Kuete, Victor; Wiench, Benjamin; Hegazy, Mohamed-Elamir F; Mohamed, Tarik A; Fankam, Aimé G; Shahat, Abdelaaty A; Efferth, Thomas

    2012-01-01

    Medicinal plants have been used as a source of remedies since ancient times in Egypt. The present study was designed to investigate the antibacterial activity and the cytotoxicity of the organic extracts from 16 selected medicinal plants of Egypt. The study was also extended to the isolation of the antiproliferative compound jaeschkeanadiol p-hydroxybenzoate (FH-25) from Ferula hermonis. The microbroth dilution was used to determine the minimal inhibitory concentration (MIC) of the samples against twelve bacterial strains belonging to four species, Providencia stuartii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli, while a resazurin assay was used to assess the cytotoxicity of the extracts on the human pancreatic cancer cell line MiaPaCa-2, breast cancer cell line MCF-7, CCRF-CEM leukemia cells, and their multidrug resistant subline, CEM/ADR5000. The results of the MIC determination indicated that all the studied crude extracts were able to inhibit the growth of at least one of the tested bacterial species, the best activity being recorded with the crude extracts from F. hermonis and Vitis vinifera, whichwere active against 91.7% and 83.3% of the studied bacteria, respectively. The lowest MIC value of 128 μg/mL was recorded against P. stuartii ATCC 29916 and E. coli ATCC 10536 with the extract from V. vinifera and Commiphora molmol, respectively. In the cytotoxicity study, IC50 values below 20 μg/mL were recorded for the crude extract of F. hermonis on all four studied cancer cell lines. FH-25 also showed good cytotoxicity against MCF-7 cells (IC50: 2.47 μg/mL). Finally, the results of the present investigation provided supportive data for the possible use of the plant extracts investigated herein, mostly F. hermonis and V. vinifera in the treatment of bacterial infections and jaeschkeanadiol p-hydroxybenzoate in the control of cancer diseases. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Biosynthesis of silver nanoparticles using Acacia leucophloea extract and their antibacterial activity.

    Science.gov (United States)

    Murugan, Kasi; Senthilkumar, Balakrishnan; Senbagam, Duraisamy; Al-Sohaibani, Saleh

    2014-01-01

    The immense potential of nanobiotechnology makes it an intensely researched field in modern medicine. Green nanomaterial synthesis techniques for medicinal applications are desired because of their biocompatibility and lack of toxic byproducts. We report the toxic byproducts free phytosynthesis of stable silver nanoparticles (AgNPs) using the bark extract of the traditional medicinal plant Acacia leucophloea (Fabaceae). Visual observation, ultraviolet-visible spectroscopy, and transmission electron microscopy (TEM) were used to characterize the synthesized AgNPs. The visible yellow-brown color formation and surface plasmon resonance at 440 nm indicates the biosynthesis of AgNP. The TEM images show polydisperse, mostly spherical AgNP particles of 17-29 nm. Fourier transform infrared spectroscopy revealed that primary amines, aldehyde/ketone, aromatic, azo, and nitro compounds of the A. leucophloea extract may participate in the bioreduction and capping of the formed AgNPs. X-ray diffraction confirmed the crystallinity of the AgNPs. The in vitro agar well diffusion method confirmed the potential antibacterial activity of the plant extract and synthesized AgNPs against the common bacterial pathogens Staphylococcus aureus (MTCC 737), Bacillus cereus (MTCC 1272), Listeria monocytogenes (MTCC 657), and Shigella flexneri (MTCC 1475). This research combines the inherent antimicrobial activity of silver metals with the A. leucophloea extract, yielding antibacterial activity-enhanced AgNPs. This new biomimetic approach using traditional medicinal plant (A. leucophloea) barks to synthesize biocompatible antibacterial AgNPs could easily be scaled up for additional biomedical applications. These polydisperse AgNPs green-synthesized via A. leucophloea bark extract can readily be used in many applications not requiring high uniformity in particle size or shape.

  16. Purity of graphene oxide determines its antibacterial activity

    Science.gov (United States)

    Barbolina, I.; Woods, C. R.; Lozano, N.; Kostarelos, K.; Novoselov, K. S.; Roberts, I. S.

    2016-06-01

    Nanomaterials based on two-dimensional (2D) atomic crystals are considered to be very promising for various life-science and medical applications, from drug delivery to tissue modification. One of the most suitable materials for these purposes is graphene oxide (GO), thanks to a well-developed methods of production and water solubility. At the same time, its biological effect is still debated. Here we demonstrate that highly purified and thoroughly washed GO neither inhibited nor stimulated the growth of E.coli, ATCC25922; E.coli NCIMB11943 and S.aureus ATCC25923 at concentrations of up to 1 mg ml-1. Moreover, transmission electron microscopy (TEM) of GO exposed bacteria did not reveal any differences between GO exposed and not exposed populations. In contrast, a suspension of insufficiently purified GO behaved as an antibacterial material due to the presence of soluble acidic impurities, that could be removed by extended purification or neutralisation by alkaline substrates. A standardised protocol is proposed for the generation of clean GO, so it becomes suitable for biological experiments. Our findings emphasise the importance of GO purification status when dealing with biological systems as the true effect of material can be masked by the impact of impurities.

  17. Y-doped zinc oxide (YZO) nanoflowers, microstructural analysis and test their antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Sanjeev Kumar, E-mail: sksharma@dongguk.edu [Semiconductor Materials and Device Laboratory, Department of Semiconductor Science, Dongguk University-Seoul, 30 Pildong-ro 1-gil, Jung-gu, Seoul 100715 (Korea, Republic of); Sudheer Pamidimarri, D.V.N. [Biomass and Waste Energy Laboratory, Korea Institute of Energy Research (KIER), 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Kim, Deuk Young, E-mail: dykim@dongguk.edu [Semiconductor Materials and Device Laboratory, Department of Semiconductor Science, Dongguk University-Seoul, 30 Pildong-ro 1-gil, Jung-gu, Seoul 100715 (Korea, Republic of); Na, Jeong-Geol [Biomass and Waste Energy Laboratory, Korea Institute of Energy Research (KIER), 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of)

    2015-08-01

    Self-assembled 3D flower-like yttrium-doped zinc oxide (YZO) microstructures composed of nanorods were prepared by hydrothermal-precipitation, and tested their antibacterial activity. The morphological, structural, and compositional properties of YZO nanoflowers were characterized by various techniques, which confirmed a well-crystallized wurtzite hexagonal phase. X-ray photoelectron spectroscopy (XPS) of YZO nanopowder showed the 3d core level spectra of yttrium (Y), which formed by two components at about 158.2 eV (3d{sub 5/2}) and 160.4 eV (3d{sub 3/2}). The antibacterial activity of YZO nanoflowers were investigated using both gram-positive and gram-negative microorganisms. Enhancement in antibacterial activity was observed by the incorporation of yttrium (Y: 2 at.%) of nanorod-based-flowers because of increased surface area. The prepared YZO nanocomposite showed potential as an antibacterial agent with applications in controlling the spread of infections and also the ability of fast antibacterial activity which can hinder the re-emergence of infection. - Highlights: • Synthesis of 3D flower-like YZO powder by hydrothermal, and antibacterial activity • XRD and XPS of YZO confirmed that Y replaced Zn interstitial sites. • 3d core level spectra of Y formed by two components at 158.2 eV (3d{sub 5/2}) & 160.4 eV (3d{sub 3/2}). • YZO-nanorod-based-flower (Y: 2 at.%) showed the best antibacterial activity. • YZO showed potential agent as the antibacterial material with applications in controlling the spread of infections.

  18. Antibacterial activity of Myrciaria dubia (Camu camu against Streptococcus mutans and Streptococcus sanguinis

    Directory of Open Access Journals (Sweden)

    Rosella Camere-Colarossi

    2016-09-01

    Conclusions: The experimental findings demonstrated the antibacterial effect of the methanol extract of M. dubia against S. mutans and S. sanguinis. These extracts were not cytotoxic at high concentrations.

  19. Antibacterial activity of kaolinite/nanoTiO2 composites in relation to irradiation time.

    Science.gov (United States)

    Dědková, Kateřina; Matějová, Kateřina; Lang, Jaroslav; Peikertová, Pavlína; Kutláková, Kateřina Mamulová; Neuwirthová, Lucie; Frydrýšek, Karel; Kukutschová, Jana

    2014-06-05

    The paper addresses laboratory preparation and antibacterial activity testing of kaolinite/nanoTiO2 composite in respect of the daylight irradiation time. Kaolinite/nanoTiO2 composites with 20 and 40 wt% of TiO2 were laboratory prepared, dried at 105 °C and calcined at 600 °C. The calcination caused transformation of kaolinite to metakaolinite and origination of the metakaolinite/nanoTiO2 composite. X-ray powder diffraction, Raman and FTIR spectroscopic methods revealed titanium dioxide only in the form of anatase in all evaluated samples (non-calcined and calcined) and also transformation of kaolinite to metakaolinite after the calcination treatment. Scanning electron microscopy was used as a method for characterization of morphology and elemental composition of the studied samples. A standard microdilution test was used to determine the antibacterial activity using four human pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa). A lamp with a wide spectrum bulb simulating daylight was used for induction of photocatalysis. The antibacterial assays found all the KATI samples to have antibacterial potency with different onset of the activity when calcined samples exhibited antibacterial activity earlier than the non-calcined. Significant difference in antibacterial activity of KATI samples for different bacterial strains was not observed. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Enhanced water-solubility and antibacterial activity of novel chitosan derivatives modified with quaternary phosphonium salt.

    Science.gov (United States)

    Zhu, Dan; Cheng, Honghao; Li, Jianna; Zhang, Wenwen; Shen, Yuanyuan; Chen, Shaojun; Ge, Zaochuan; Chen, Shiguo

    2016-04-01

    Chitosan (CS) has been widely recognized as an important biomaterial due to its good antimicrobial activity, biocompatibility and biodegradability. However, CS is insoluble in water in neutral and alkaline aqueous solution due to the linear aggregation of chain molecules and the formation of crystallinity. This is one of the key factors that limit its practical applications. Therefore, improving the solubility of CS in neutral and alkaline aqueous solution is a primary research direction for biomedical applications. In this paper, a reactive antibacterial compound (4-(2,5-Dioxo-pyrrolidin-1-yloxycarbonyl)-benzyl)-triphenyl-phosphonium bromide (NHS-QPS) was synthesized for chemical modification of CS, and a series of novel polymeric antimicrobial agents, N-quaternary phosphonium chitosan derivatives (N-QPCSxy, x=1-2,y=1-4) were obtained. The water solubilities and antibacterial activities of N-QPCSxy against Escherichia coli and Staphylococcus aureus were evaluated compare to CS. The water solubility of N-QPCSxy was all better than that of CS at neutral pH aqueous solution, particularly, N-QPCS14 can be soluble in water over the pH range of 3 to 12. The antibacterial activities of CS derivatives were improved by introducing quaternary phosphonium salt, and antibacterial activity of N-QPCSxy increases with degree of substitution. Overall, N-QPCS14 represents a novel antibacterial polymer material with good antibacterial activity, waters solubility and low cytotoxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. A Novel Surface Structure Consisting of Contact-active Antibacterial Upper-layer and Antifouling Sub-layer Derived from Gemini Quaternary Ammonium Salt Polyurethanes

    Science.gov (United States)

    He, Wei; Zhang, Yi; Li, Jiehua; Gao, Yunlong; Luo, Feng; Tan, Hong; Wang, Kunjie; Fu, Qiang

    2016-08-01

    Contact-active antibacterial surfaces play a vital role in preventing bacterial contamination of artificial surfaces. In the past, numerous researches have been focused on antibacterial surfaces comprising of antifouling upper-layer and antibacterial sub-layer. In this work, we demonstrate a reversed surface structure which integrate antibacterial upper-layer and antifouling sub-layer. These surfaces are prepared by simply casting gemini quaternary ammonium salt waterborne polyurethanes (GWPU) and their blends. Due to the high interfacial energy of gemini quaternary ammonium salt (GQAS), chain segments containing GQAS can accumulate at polymer/air interface to form an antibacterial upper-layer spontaneously during the film formation. Meanwhile, the soft segments composed of polyethylene glycol (PEG) formed the antifouling sub-layer. Our findings indicate that the combination of antibacterial upper-layer and antifouling sub-layer endow these surfaces strong, long-lasting antifouling and contact-active antibacterial properties, with a more than 99.99% killing efficiency against both gram-positive and gram-negative bacteria attached to them.

  2. Streptomyces luozhongensis sp. nov., a novel actinomycete with antifungal activity and antibacterial activity.

    Science.gov (United States)

    Zhang, Renwen; Han, Xiaoxue; Xia, Zhanfeng; Luo, Xiaoxia; Wan, Chuanxing; Zhang, Lili

    2017-02-01

    A novel actinomycete strain, designated TRM 49605(T), was isolated from a desert soil sample from Lop Nur, Xinjiang, north-west China, and characterised using a polyphasic taxonomic approach. The strain exhibited antifungal activity against the following strains: Saccharomyces cerevisiae, Curvularia lunata, Aspergillus flavus, Aspergillus niger, Fusarium oxysporum, Penicillium citrinum, Candida albicans and Candida tropicalis; Antibacterial activity against Bacillus subtilis, Staphylococcus epidermidis and Micrococcus luteus; and no antibacterial activity against Escherichia coli. Phylogenetic analysis based on 16S rRNA gene sequences affiliated strain TRM 49605(T) to the genus Streptomyces. Strain TRM 49605(T) shows high sequence similarities to Streptomyces roseolilacinus NBRC 12815(T) (98.62 %), Streptomyces flavovariabilis NRRL B-16367(T) (98.45 %) and Streptomyces variegatus NRRL B-16380(T) (98.45 %). Whole cell hydrolysates of strain TRM 49605(T) were found to contain LL-diaminopimelic acid as the diagnostic diamino acid and galactose, glucose, xylose and mannose as the major whole cell sugars. The major fatty acids in strain TRM 49605(T) were identified as iso C16:0, anteiso C15:0, C16:0 and Summed Feature 5 as defined by MIDI. The main menaquinones were identified as MK-9(H4), MK-9(H6), MK-9(H8) and MK-10(H6). The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol and phosphatidylinositol mannoside. The G+C content of the genomic DNA was determined to be 71.2 %. The DNA-DNA relatedness between strain TRM 49605(T) and the phylogenetically related strain S. roseolilacinus NBRC 12815(T) was 60.12 ± 0.06 %, which is lower than the 70 % threshold value for delineation of genomic prokaryotic species. Based on the phenotypic, chemotaxonomic and phylogenetic data, strain TRM 49605(T) (=CCTCC AA2015026(T) = KCTC 39666(T)) should be designated as the type strain of a novel species of the genus

  3. Antibacterial activity of dental composites containing zinc oxide nanoparticles.

    Science.gov (United States)

    Aydin Sevinç, Berdan; Hanley, Luke

    2010-07-01

    The resin-based dental composites commonly used in restorations result in more plaque accumulation than other materials. Bacterial biofilm growth contributes to secondary caries and failure of resin-based dental composites. Methods to inhibit biofilm growth on dental composites have been sought for several decades. It is demonstrated here that zinc oxide nanoparticles (ZnO-NPs) blended at 10% (w/w) fraction into dental composites display antimicrobial activity and reduce growth of bacterial biofilms by roughly 80% for a single-species model dental biofilm. Antibacterial effectiveness of ZnO-NPs was assessed against Streptococcus sobrinus ATCC 27352 grown both planktonically and as biofilms on composites. Direct contact inhibition was observed by scanning electron microscopy and confocal laser scanning microscopy while biofilm formation was quantified by viable counts. An 80% reduction in bacterial counts was observed with 10% ZnO-NP-containing composites compared with their unmodified counterpart, indicating a statistically significant suppression of biofilm growth. Although, 20% of the bacterial population survived and could form a biofilm layer again, 10% ZnO-NP-containing composites maintained at least some inhibitory activity even after the third generation of biofilm growth. Microscopy demonstrated continuous biofilm formation for unmodified composites after 1-day growth, but only sparsely distributed biofilms formed on 10% ZnO-NP-containing composites. The minimum inhibitory concentration of ZnO-NPs suspended in S. sobrinus planktonic culture was 50 microg mL(-1). ZnO-NP-containing composites (10%) qualitatively showed less biofilm after 1-day-anaerobic growth of a three-species initial colonizer biofilm after being compared with unmodified composites, but did not significantly reduce growth after 3 days. (c) 2010 Wiley Periodicals, Inc.

  4. Antioxidant, Antibacterial, and Cytoprotective Activity of Agathi Leaf Protein

    Directory of Open Access Journals (Sweden)

    A. S. Zarena

    2014-01-01

    Full Text Available In the present study a protein termed agathi leaf protein (ALP from Sesbania grandiflora Linn. (agathi leaves was isolated after successive precipitation with 65% ammonium sulphate followed by purification on Sephadex G 75. The column chromatography of the crude protein resulted in four peaks of which Peak I (P I showed maximum inhibition activity against hydroxyl radical. SDS-PAGE analysis of P I indicated that the molecular weight of the protein is ≈29 kDa. The purity of the protein was 98.4% as determined by RP-HPLC and showed a single peak with a retention time of 19.9 min. ALP was able to reduce oxidative damage by scavenging lipid peroxidation against erythrocyte ghost (85.50 ± 6.25%, linolenic acid (87.67 ± 3.14% at 4.33 μM, ABTS anion (88 ± 3.22%, and DNA damage (83 ± 4.20% at 3.44 μM in a dose-dependent manner. The purified protein offered significant protection to lymphocyte (72% at 30 min induced damage by t-BOOH. In addition, ALP showed strong antibacterial activity against Pseudomonas aeruginosa (20 ± 3.64 mm and Staphylococcus aureus (19 ± 1.53 mm at 200 μg/mL. The safety assessment showed that ALP does not induce cytotoxicity towards human lymphocyte at the tested concentration of 0.8 mg/mL.

  5. The synthesis and antibacterial activity of pyrazole-fused tricyclic diterpene derivatives.

    Science.gov (United States)

    Yu, Li-Gang; Ni, Teng-Feng; Gao, Wei; He, Yuan; Wang, Ying-Ying; Cui, Hai-Wei; Yang, Cai-Guang; Qiu, Wen-Wei

    2015-01-27

    The diterpenoid compound 5 was identified as an antibacterial lead in our screening of small synthetic natural product-like (NPL) library. A series of novel diterpene derivatives were synthesized and investigated for their activity against Staphylococcus aureus Newman strain and multidrug-resistant strains (NRS-1, NRS-70, NRS-100, NRS-108 and NRS-271). Among the compounds tested, 42 and 43 showed highest activity with a MIC of 1 μg/mL against strain Newman, 45 and 52 showed the most potent activity with MIC values of 0.71-3.12 μg/mL against five multidrug-resistant S. aureus. All high-antimicrobial active compounds showed no obvious toxicity to human fibroblast (HAF) cells at the MIC concentration.

  6. Antibacterial Activity and Action Mechanism of the Essential Oil from Enteromorpha linza L. against Foodborne Pathogenic Bacteria.

    Science.gov (United States)

    Patra, Jayanta Kumar; Baek, Kwang-Hyun

    2016-03-21

    Foodborne illness and disease caused by foodborne pathogenic bacteria is continuing to increase day by day and it has become an important topic of concern among various food industries. Many types of synthetic antibacterial agents have been used in food processing and food preservation; however, they are not safe and have resulted in various health-related issues. Therefore, in the present study, essential oil from an edible seaweed, Enteromorpha linza (AEO), was evaluated for its antibacterial activity against foodborne pathogens, along with the mechanism of its antibacterial action. AEO at 25 mg/disc was highly active against Bacillus cereus (12.3-12.7 mm inhibition zone) and Staphylococcus aureus (12.7-13.3 mm inhibition zone). The minimum inhibitory concentration and minimum bactericidal concentration values of AEO ranged from 12.5-25 mg/mL. Further investigation of the mechanism of action of AEO revealed its strong impairing effect on the viability of bacterial cells and membrane permeability, as indicated by a significant increase in leakage of 260 nm absorbing materials and K⁺ ions from the cell membrane and loss of high salt tolerance. Taken together, these data suggest that AEO has the potential for use as an effective antibacterial agent that functions by impairing cell membrane permeability via morphological alternations, resulting in cellular lysis and cell death.

  7. In-vitro antibacterial activity on human pathogens and total phenolic, flavonoid contents of Murraya paniculata Linn. leaves

    Institute of Scientific and Technical Information of China (English)

    Manish K Gautam; Mayank Gangwar; Gopal Nath; Chandana V Rao; Raj K Goel

    2012-01-01

    Objective: To deals with in-vitro antibacterial analysis of Murraya paniculata Linn. (Rutaceae) leaves extract on human pathogens in different solvent and determination of total phenolic and flavonoid contents in petroleum ether, methanol, ethanol and hydro-alcoholic extract of the plant.Methods:These extracts were tested against various human pathogens for antimicrobial activity which was evaluated by disc diffusion method and minimum inhibitory concentration (MIC) and minimum bactericidal concentration was calculated by micro dilution method. Phenolic content was estimated by using folin ciocalteau reagent and flavonoids by using aluminium chloride reagent against quercetin equivalent. Results: The methanolic extract of leaf showed marked antibacterial activities against gram-positive and gram-negative bacteria. Methanolic extract of Murraya paniculata leaf contain higher phenolic content (24.80±0.64) followed by ethanolic fraction (15.40±0.38), pet. Ether (13.50±0.96) and hydro-alcoholic (9.06±1.13). Flavonoid content was found to be maximum in pet. ether extracts (3.38±1.89). Conclusions: Murraya paniculata leaves posses antibacterial properties against human pathogens with high content of phenolic and flavonoids, which have supportive action of antibacterial activity. Studying plant based antimicrobial properties provides additional information in developing nature antibiotics and discovering the alternative of antimicrobial drugs for the treatment of infectious disease.

  8. Screening of Taiwanese crude drugs for antibacterial activity against Streptococcus mutans.

    Science.gov (United States)

    Chen, C P; Lin, C C; Namba, T

    1989-12-01

    Preliminary antibacterial screening of local crude drugs was carried out using the cariogenic bacterium, Streptococcus mutans. Of 79 aqueous extracts tested, 6 crude drugs were shown to have significant antibacterial activity with minimal inhibitory concentration equal to or lower than 7.8 mg/ml (expressed in terms of dry starting material). Of these effective crude drugs, Morus australis, Ludwigia octovalvis and Thuja orientalis were very effective in inhibiting the growth of serotypes c and d of S. mutans (MIC less than or equal to 2.0-7.8 mg/ml). Elephantopus scaber, Artemisia vulgaris, Mosla chinensis and Orthosiphon aristatus also exhibited considerable antibacterial activity (MIC = 7.8-23.4 mg/ml) against both serotypes. In the presence of 5% sucrose, the antibacterial potency of the majority of the extracts did not change for type c, while the potency decreased about one-half for type d.

  9. Biosynthesis of silver nanoparticles using Acacia leucophloea extract and their antibacterial activity

    Directory of Open Access Journals (Sweden)

    Murugan K

    2014-05-01

    traditional medicinal plant (A. leucophloea barks to synthesize biocompatible antibacterial AgNPs could easily be scaled up for additional biomedical applications. These polydisperse AgNPs green-synthesized via A. leucophloea bark extract can readily be used in many applications not requiring high uniformity in particle size or shape.Keywords: AgNPs, antibacterial activity, Acacia leucophloea, biogenic, FTIR, XRD, TEM

  10. Cytotoxic and antibacterial activity of the mixture of olive oil and lime cream in vitro conditions.

    Science.gov (United States)

    Sumer, Zeynep; Yildirim, Gulay; Sumer, Haldun; Yildirim, Sahin

    2013-01-01

    The mixture of olive oil and lime cream has been traditionally used to treat external burns in the region of Hatay/Antakya and middle Anatolia. Olive oil and lime cream have been employed by many physicians to treat many ailments in the past. A limited number of studies have shown the antibacterial effect of olive oil and that it does not have any toxic effect on the skin. But we did not find any reported studies on the mixture of olive oil and lime cream. The aim of this paper is to investigate the cytotoxic and antibacterial activity of olive oil and lime cream individually or/and in combination in vitro conditions, by using disk-diffusion method and in cell culture. The main purpose in using this mixture is usually to clear burns without a trace. Agar overlay, MTT (Cytotoxicity assay) and antibacterial susceptibility tests were used to investigate the cytotoxic and antibacterial activity of olive oil and lime cream. We found that lime cream has an antibacterial activity but also cytotoxic on the fibroblasts. On the other hand olive oil has limited or no antibacterial effect and it has little or no cytotoxic on the fibroblasts. When we combined lime cream and olive oil, olive oil reduced its cytotoxic impact. These results suggest that mixture of olive oil and lime cream is not cytotoxic and has antimicrobial activity.

  11. Phytochemical screening, cytotoxicity and antibacterial activities of two Bangladeshi medicinal plants.

    Science.gov (United States)

    Roy, Ajoy; Biswas, Subrata Kumar; Chowdhury, Anusua; Shill, Manik Chandra; Raihan, Sheikh Zahir; Muhit, Md Abdul

    2011-10-01

    The objectives of the present study were to investigate phytochemical screening and to assay cytotoxicity and antibacterial activities of ethanolic extracts of leaves of two medicinal plants, Aglaonema hookerianum Schott (Family: Araceae) and Lannea grandis Engl. (Family: Anacardiaceae) available in Bangladesh. The brine shrimp lethality bioassay showed that the ethanolic extracts of Aglaonema hookerianum and Lannea grandis possessed cytotoxic activities with LC50 5.25 (microg mL(-1)) and 5.75 (microg mL(-1)) and LC90 10.47 (microg mL(-1)) and 9.55 (microg mL(-1)), respectively. Two extracts obtained from leaves were examined for their antibacterial activities against some gram positive bacteria such as Bacillus subtilis, Bacillus megaterium and Staphylococcus aureus, also gram negative strains of Pseudomonas aeruginosa, Escherichia coli, Shigella dysenteriae, Salmonella typhi, Salmonella paratyphi and Vibrio cholerae. Agar disc diffusion method was applied to observe the antibacterial efficacy of the extracts. Results indicated that both plant extracts (500 microg disc(-1)) displayed antibacterial activity against all of the tested microorganisms. These results were also compared with the zones of inhibition produced by commercially available standard antibiotic, Amoxicillin at concentration of 10 microg disc(-1). Observed antibacterial properties of the ethanolic extract of Aglaonema hookerianum Schott and Lannea grandis Engl. showed that both plants might be useful sources for the development of new potent antibacterial agents.

  12. Degradation of streptomycin in aquatic environment: kinetics, pathway, and antibacterial activity analysis.

    Science.gov (United States)

    Shen, Yanru; Zhao, Wenyan; Zhang, Chunling; Shan, Yujie; Shi, Junxian

    2017-06-01

    Streptomycin used in human and veterinary medicine is released into the environment mainly through excretions. As such, its elimination in water should be investigated to control pollution. In this study, the degradation of streptomycin in water was studied, and the influence of variables, including light exposure, solution pH, temperature, ionic strength, dissolved organic matter (DOM), and coexisting surfactants, on degradation was investigated. Streptomycin degradation was consistent with the first-order model in aquatic environments. Its degradation rate under light exposure was 2.6-fold faster than that in the dark. Streptomycin was stable under neutral conditions, but it was easily decomposed in acidic and basic environments. Streptomycin degradation was enhanced by high temperature, and its half-life decreased from 103.4 days at 15 °C to 30.9 days at 40 °C. This process was also accelerated by the presence of Ca(2+) and slightly improved by the addition of HA. Streptomycin degradation was suppressed by high levels of the cationic surfactant cetyltri- methylammonium bromide (CTAB), but was promoted by the anionic surfactant sodium dodecyl benzene sulfonate (SDBS). The main degradation intermediates/products were identified through liquid chromatography-mass spectrometry, and the possible degradation pathway was proposed. The antibacterial activity of streptomycin solution was also determined during degradation. Results showed that STR degradation generated intermediates/products with weaker antibacterial activity than the parent compound.

  13. Green biosynthesis of gold nanoparticles using Galaxaura elongata and characterization of their antibacterial activity

    Directory of Open Access Journals (Sweden)

    Neveen Abdel-Raouf

    2017-05-01

    Full Text Available The synthesis of gold nanoparticles (Au using Galaxaura elongata (powder or extract is demonstrated here. The rapid formation of stable Au nanoparticles has been found using G. elongata extract in aqueous medium at normal atmospheric condition. Transmission electron microscopy (TEM analysis revealed that the particles are spherical in shape along with a few rod, triangular, truncated triangular and hexagonal shaped nanoparticles. Zeta potential measurements indicated that the Au nanoparticles were in the size range of 3.85–77.13 nm. Fourier transform infrared spectroscopy (FTIR showed that nanoparticles were capped with alga compounds. The chemical constituents, viz. Andrographolide, Alloaromadendrene oxide, glutamic acid, hexadecanoic acid, oleic acid, 11-eicosenoic acid, stearic acid, gallic acid, Epigallocatechin Catechin and Epicatechin gallate of the algal extract were identified which may act as a reducing, stabilizing and capping agent. The nanoparticles were also evaluated for their antibacterial activities which showed better antibacterial effects with maximum inhibition zones of 17–16 mm by AuNPs synthesized by ethanolic extract against Escherichia coli, Klebsiella pneumoniae and MRSA, respectively, followed by Staphylococcus aureus and Pseudomonas aeruginosa (13 mm. Furthermore, the nanoparticles synthesized by the powder of G. elongata were found to be highly effective against E. coli and K. pneumoniae (13.5 and 13 mm, respectively. On the other hand, the free ethanolic extract of G. elongata exhibits high activity only against MRSA (14 mm.

  14. Antibacterial activity of crude extract of Punica granatum pericarp on pathogenic Gram-negative bacilli.

    Directory of Open Access Journals (Sweden)

    Voravuthikunchai, S.

    2005-08-01

    Full Text Available The objective of this study was to investigate the effect of crude extracts of Punica granatum Linn. pericarp with 3 different solvents against pathogenic Gram-negative bacilli. Ethanolic extracts showed the antibacterial activity against all strains tested including enterohaemorrhagic Escherichia coli 4 strains (E. coli O157: H7, E. coli O26: H11, E. coli O111: NM, E. coli O22, Pseudomonas aeruginosa, Shigella boydii and Salmonella london. Inhibition zones ranged from 10.02 to 19.15 mm. Minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC ranged from 0.09 to 3.13 mg/ml and 3.13 to 25 mg/ml, respectively. Aqueous extract had low antibacterial activity while crude chloroform extracts had no effect on the growth of these strains. Ethyl acetate and n-butanol fractions of P. granatum pericarp demonstrated high activity with the best MIC and MBC values of 0.02 to 0.78 mg/ml and 0.19 to 6.25 mg/ml, respectively. As ethanolic extract of P. granatum was very effective against these pathogenic bacteria, further investigation on this plant species may provide alternative, but bioactive, medicines for the treatment of Gram-negative bacterial infection.

  15. A Study on the Antibacterial Activity Of Zno Nanoparticles Prepared By Combustion Method against E Coli

    Directory of Open Access Journals (Sweden)

    Durga Prasad

    2014-06-01

    Full Text Available Crystalline Zinc Oxide (ZnO nanoparticles were synthesized by low temperature solution combustion method using Oxalyl dihydrazide (ODH as fuel, at much lower temperature (300oC. X-ray diffraction (XRD confirmed the formation of wurtzite-structured pure ZnO No peaks from any else phases of ZnO and no impurity peaks were observed, indicating the high purity of the obtained hexagonal ZnO nanocrystals. The antibacterial activity of the formed nano ZnO were investigated against the pathogenic bacteria namely against E-coli. The bacteriological test is performed in Luria-Bertani and Nutrient agar media on solid agar plates and liquid broth system using different concentration of ZnO by standard microbial method. We have used both colony counting method and disk diffusion method. In both the methods ZnO nanoparticles with 100microg/L showed best antibacterial activity, and further studies on destruction of bacterial genomic DNA was done using PCR and gel electrophoresis revealed the DNA fragment bands, this activity might be due to surface charge interactions between the particles and cells. Free radical scavenging properties of the particles might have helped in cell wall disruption, and drastic antimicrobial action.

  16. Enhanced polarization, magnetic response and pronounced antibacterial activity of bismuth ferrite nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Kunal [Department of Biotechnology, Maulana Abul Kalam Azad University of Technology, West Bengal, Kolkata-64 (India); De, Debashis, E-mail: dr.debashis.de@ieee.org [Department of Computer Science and Engineering, Maulana Abul Kalam Azad University of Technology, West Bengal, Kolkata-64 (India); Bandyopadhyay, Jaya [Department of Biotechnology, Maulana Abul Kalam Azad University of Technology, West Bengal, Kolkata-64 (India); Dutta, Nabanita; Rana, Subhasis; Sen, Pintu [Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata, 700 064 (India); Bandyopadhyay, Sujit Kumar, E-mail: drsujitkumar@gmail.com [Meghnad Saha Institute of Technology, Nazirabad Rd, Uchhepota, Kolkata, West Bengal, 700150 (India); Chakraborty, P.K. [Department of Physics, Burdwan University, Burdwan, 713104 (India)

    2017-07-01

    The present work reports on the physical and biophysical characterization of bismuth ferrite (BFO) nanorods fabricated on porous anodized alumina (AAO) templates. The diameter of the nanorods was quite large, which vary in the range of 20–100 nm. The BFO nanorods exhibited enhanced polarization and significant magnetic susceptibility. Moreover, an enhanced magnetoelectric coupling was evident from magnetocapacitance measurements, which exhibited a power law. Upon analyzing through optical, petri-plate and electron microscopy imaging, we observed that, the asymmetric structure of the nanorods gave rise to augmented antibacterial response against the chosen bacteria (Staphylococcus aureus). The x-ray photoelectron spectra (XPS) data have exhibited significant peak shifts upon interaction with bacterial cells owing to a change of Bi oxidation state from one to another. Thus potential redox reaction, which might take place at the material-bio interface, is ascertained for bacterial death. Apart from physical insights, understanding the interaction between the bacteria and the nanorods of BFO could pave the way in exploring the antibacterial potentiality of such anisotropic nanoscale systems. - Highlights: • AAO supported BiFeO3 (BFO) nanorods have been investigated. • The polarization of BFO nanorods was observed to be remarkably high (∼0.04 μC/cm{sup 2}). • Strong antibacterial activity of nanorods was witnessed against Staphylococcus aureus. • The deskinned area on cytoskeletal parts as revealed through TEM imaging, suggest strong cidal activity of the nanorods. • XPS data justifies shifting of the peak due to biophysical interaction at the interface releasing reactive oxygen species.

  17. Antibacterial activity of single crystalline silver-doped anatase TiO{sub 2} nanowire arrays

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiangyu, E-mail: zhangxiangyu@tyut.edu.cn; Li, Meng; He, Xiaojing; Hang, Ruiqiang; Huang, Xiaobo; Wang, Yueyue; Yao, Xiaohong; Tang, Bin, E-mail: tangbin@tyut.edu.cn

    2016-05-30

    Graphical abstract: The silver-doped TiO{sub 2} nanowire arrays on titanium foil substrate were synthesized via a two-step process. It includes: deposition of AgTi films on titanium foil by magnetron sputtering; preparation of AgNW arrays on AgTi films via alkali (NaOH) hydrothermal treatment and ion-exchange with HCl, followed by calcinations. - Highlights: • Ag-doped TiO{sub 2} nanowire arrays have been prepared by a duplex-treatment. • The duplex-treatment consisted of magnetron sputtering and hydrothermal growth. • Ag-doped nanowire arrays show excellent antibacterial activity against E. coli. - Abstract: Well-ordered, one-dimensional silver-doped anatase TiO{sub 2} nanowire (AgNW) arrays have been prepared through a hydrothermal growth process on the sputtering-deposited AgTi layers. Electron microscope analyses reveal that the as-synthesized AgNW arrays exhibit a single crystalline phase with highly uniform morphologies, diameters ranging from 85 to 95 nm, and lengths of about 11 μm. Silver is found to be doped into TiO{sub 2} nanowire evenly and mainly exists in the zerovalent state. The AgNW arrays show excellent efficient antibacterial activity against Escherichia coli (E. coli), and all of the bacteria can be killed within 1 h. Additionally, the AgNW arrays can still kill E. coli after immersion for 60 days, suggesting the long-term antibacterial property. The technique reported here is environmental friendly for formation of silver-containing nanostructure without using any toxic organic solvents.

  18. Synthesis, antibacterial and antifungal activity of some derivatives of 2-phenyl-chromen-4-one

    Indian Academy of Sciences (India)

    Sayed Alam

    2004-11-01

    Some derivatives of 2-phenyl-chromen-4-one (flavone ring) have been synthesized and tested for antibacterial and antifungal activities along with their chalcone precursors against four human pathogenic bacteria and five plant mould fungi. The structures of the synthesized compounds were elucidated by UV, IR and 1H NMR spectroscopic techniques, and elemental analysis. The antibacterial and antifungal screens of the synthesized compounds were performed in vitro by the filter paper disc diffusion method and the poisoned food technique.

  19. Screening of antibacterial activity in marine green and brown macroalgae from the coast of Morocco

    OpenAIRE

    Ibtissam, Chiheb; Hassane, Riadi; Mart??nez L??pez, Jos??; Dom??nguez Seglar, Jos?? Francisco; G??mez Vidal, Jos?? Antonio; Hassan, Bouziane; Mohamed, Kadiri

    2009-01-01

    Antibacterial activity of methanolic extracts from 32 macroalgae (13 Chlorophyta and 19 Phaeophyta) from the Atlantic and Mediterranean coast of Morocco were evaluated for the production of antibacterial compounds against Escherichia coliATCC 25922, Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Klebsiella pnomeuniae ATCC 700603 and E. faecalis ATCC 29213. Our results indicate that these species of seaweed collected from the Atlantic and Mediterranean coast of Morocco pre...

  20. ANTIBACTERIAL ACTIVITY ESSENTIALS OILS PONTIANAK ORANGE PEELS AGAINST Staphylococcus aureus and Escherichia coli

    OpenAIRE

    Sari, Rafika; Mustari, F. Nour Aulia; Wahdaningsih, Sri

    2015-01-01

    The infectious diseases can be caused by the pathogenic bacteria among Staphylococcus aureus and Escherichia coli. One of the plants that can be used as antibacterial is essential oils from Pontianak orange peels (Citrus nobilis Lour. var. microcarpa). This research aims to determine the antibacterial activity essential oils Pontianak orange peels againts the pathogenic bacteria by disc diffusion method. This research carried out by using the experimental Completely Randomized Design (CRD) Fa...

  1. Antifungal and antibacterial activities of Mexican tarragon (Tagetes lucida).

    Science.gov (United States)

    Céspedes, Carlos L; Avila, J Guillermo; Martínez, Andrés; Serrato, Blanca; Calderón-Mugica, José C; Salgado-Garciglia, Rafael

    2006-05-17

    Mexican tarragon (Tagetes lucida Cv. Asteraceae: Campanulatae) is an important, nutritious plant and an effective herbal medicine. Seven coumarins, 7,8-dihydroxycoumarin (4), umbelliferone (7-hydroxycoumarin) (5), scoparone (6,7-dimethoxycoumarin) (7), esculetin (6,7-dihydroxycoumarin) (11), 6-hydroxy-7-methoxycoumarin (12), herniarin (7-methoxycoumarin) (13), and scopoletin (6-methoxy-7-hydroxycoumarin) (14), and three flavonoids, patuletin (18), quercetin (19), and quercetagetin (20), were isolated from CH2Cl2 and MeOH extracts from aerial parts of T. lucida. In addition, 6,7-diacetoxy coumarin (15), 6-methoxy-7-acetylcoumarin (16), and 6-acetoxy-7-methoxycoumarin (17) derivatives were synthesized. 8-Methoxypsoralen (1), 8-acetyl-7-hydroxycoumarin (2), 7,8-dihydroxy-6-meth-oxycoumarin (3), 6,7-dimethoxy-4-methylcoumarin (6), 5,7-dihydroxy-4-methylcoumarin (8), 4-hydroxycoumarin (9), 4-hydroxy-6,7-dimethylcoumarin (10), naringenin (21), glycoside-7-rhamnonaringin (22), and rutin (23) were commercially obtained (Sigma-Aldrich). All of these compounds and extracts (M1 and M2) were assayed against bacteria and fungi. The antibacterial activity was determined on Bacillus subtilis, Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Salmonella typhi, Salmonella sp., Shigella boydii, Shigella sp., Enterobacter aerogenes, Enterobacter agglomerans, Sarcina lutea, Staphylococcus epidermidis, Staphylococcus aureus, Yersinia enterolitica, Vibrio cholerae (three El Tor strains, CDC-V12, clinic case, and INDRE-206, were obtained from contaminated water), and V. cholerae (NO-O1). The evaluated fungi were Aspergillus niger, Penicillium notatum, Fusarium moniliforme, Fusarium sporotrichum, Rhizoctonia solani, and Trichophyton mentagrophytes. The most active compounds against Gram-positive and -negative bacteria were the dihydroxylated coumarins 3 and 4. In addition, 2-4, 6, 7, and 11 showed an interesting activity against V. cholerae, a key bacterium in the contaminated

  2. Antibacterial activity of Phyllantus emblica, Coriandrum sativum, Culinaris medic, Lawsonia alba and Cucumis sativus.

    Science.gov (United States)

    Khan, Dawood Ali; Hassan, Fouzia; Ullah, Hanif; Karim, Sabiha; Baseer, Abdul; Abid, Mobasher Ali; Ubaidi, Muhammad; Khan, Shujaat Ali; Murtaza, Ghulam

    2013-01-01

    Present study deals with the demonstration of the antibacterial activity of very common medicinal plants of Pakistani origin i.e., Phyllantus emblica, Coriandrum sativum, Culinaris medic, Lawsonia alba and Cucumis sativus. The extracts were prepared in crude form by the use of hydro-alcoholic solution and were screened for antibacterial activity against various bacterial species by disk diffusion method. Assay was performed using clinical isolates of B. cereus, S. aureus, P. aeruginosa and E. coli. Crude extract of Phyllantus emblica fruit exhibited strong activity against standard cultures of all studied bacteria. Lawsonia alba showed good activity against standard cultures of all the used microorganisms. Coriandrum sativum was effective only against Bacillus cereus, while Cucumis sativus and Culinaris medic showed poor activity against Pseudomonas aeruginosa only. Hence, Phyllantus emblica exhibited strong antibacterial activity against a wide range of bacteria it means that Phyllantus emblica extract contains some compounds which have broad spectrum of bactericidal activity.

  3. Synthesis and concentration dependent antibacterial activities of CuO nanoflakes

    Energy Technology Data Exchange (ETDEWEB)

    Pandiyarajan, T.; Udayabhaskar, R. [Department of Physics, National Institute of Technology, Tiruchirappalli 620 015 (India); Vignesh, S.; James, R. Arthur [Department of Marine Science, Bharathidasan University, Tiruchirappalli 620 024 (India); Karthikeyan, B., E-mail: balkarin@yahoo.com [Department of Physics, National Institute of Technology, Tiruchirappalli 620 015 (India)

    2013-05-01

    We report, synthesis and antibacterial activities of CuO nanoflakes. CuO nanoparticles are prepared at room temperature through sol–gel method. X-ray diffraction studies show the particles are monoclinic (crystalline) in nature. Scanning electron microscopy (SEM) images clearly show that the prepared particles are flake like in structure. Fourier transform infrared (FTIR) spectra exhibits three different bands that correspond to the A{sub u} and B{sub u} modes. Antibacterial studies were performed on Shigella flexneri, Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhimurium, Bacillus subtilis, Escherichia coli, Vibrio cholera, Pseudomonas aeruginosa and Aeromonas liquefaciens bacterial strains. Among these bacterial strains, S. flexneri and B. subtilis are most sensitive to copper oxide nanoparticles than the positive control (Penicillin G) and S. typhimurium strain shows the less sensitive. Results show that sensitivity is highly dependent on the concentrations of CuO nanoflakes. - Highlights: ► CuO nanoflakes are prepared through simple sol–gel method at room temperature. ► Bacterial strains are highly affected by CuO nanoflakes than the positive control. ► Zone of inhibition increases with an increase of CuO concentrations. ► Sensitivity is highly dependent on the concentrations of CuO nanoflakes.

  4. Is the effect of surface modifying molecules on antibacterial activity universal for a given material?

    Science.gov (United States)

    Hsu, Alexander; Liu, Fangzhou; Leung, Yu Hang; Ma, Angel P. Y.; Djurišić, Aleksandra B.; Leung, Frederick C. C.; Chan, Wai Kin; Lee, Hung Kay

    2014-08-01

    Antibacterial activity of nanomaterials is strongly dependent on their properties, and their stability and toxicity can be varied using surface coatings. We investigated the effect of different surface modifying molecules on the antibacterial properties of two ZnO nanoparticle samples. We found that the starting surface properties of the nanoparticles have significant effects on the attachment of the surface modifying molecules and consequent antibacterial activity. Two out of five investigated surface modifying molecules not only had a significant difference in the magnitude of their effect on different nanoparticles, but also resulted in the opposite effects on two ZnO nanoparticle samples (an enhancement of antibacterial activity for one and a reduction of antibacterial activity for the other ZnO sample). This indicates that no general rule on the effect of a specific molecule on the toxicity of a metal oxide nanoparticle can be derived without knowing the nanoparticle properties, due to the fact that surface modifier attachment onto the surface is affected by the initial surface properties.Antibacterial activity of nanomaterials is strongly dependent on their properties, and their stability and toxicity can be varied using surface coatings. We investigated the effect of different surface modifying molecules on the antibacterial properties of two ZnO nanoparticle samples. We found that the starting surface properties of the nanoparticles have significant effects on the attachment of the surface modifying molecules and consequent antibacterial activity. Two out of five investigated surface modifying molecules not only had a significant difference in the magnitude of their effect on different nanoparticles, but also resulted in the opposite effects on two ZnO nanoparticle samples (an enhancement of antibacterial activity for one and a reduction of antibacterial activity for the other ZnO sample). This indicates that no general rule on the effect of a specific

  5. Antibacterial spectrum and cytotoxic activities of serrulatane compounds from the Australian medicinal plant Eremophila neglecta.

    Science.gov (United States)

    Anakok, O F; Ndi, C P; Barton, M D; Griesser, H J; Semple, S J

    2012-01-01

    To determine the antibacterial spectrum and cytotoxic activities of serrulatane compounds from the Australian plant Eremophila neglecta. Antimicrobial activities of serrulatane compounds 8,19-dihydroxyserrulat-14-ene (1) and 8-hydroxyserrulat-14-en-19-oic acid (2) were tested against Gram-negative and Gram-positive bacteria including human and veterinary pathogens and some multidrug-resistant isolates. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of the compounds were determined by broth microdilution assay. Both compounds exhibited antibacterial activity against all Gram-positive test strains. They showed antimycobacterial activity against isolates of Mycobacterium fortuitum and Mycobacterium chelonae. Of the five Gram-negative bacteria tested, only Moraxella catarrhalis showed susceptibility to the compounds. Cytotoxic activities were tested in the Vero cell line. Compound 1 showed more activity than 2 in both antibacterial and cytotoxicity assays with cytotoxicity at concentrations similar to the MBC. Serrulatane compounds showed significant activity against medically important bacteria, with 1 exhibiting stronger antibacterial activity. However, they also displayed toxicity to mammalian cells. Serrulatanes are of interest as novel antibacterial compounds for use in biomedical applications; this study reports data obtained with a range of bacterial strains and mammalian cells, essential for assessing the capabilities and limitations of potential applicability of these compounds. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  6. Synthesis and structure-activity relationships of novel amino/nitro substituted 3-arylcoumarins as antibacterial agents.

    Science.gov (United States)

    Matos, Maria J; Vazquez-Rodriguez, Saleta; Santana, Lourdes; Uriarte, Eugenio; Fuentes-Edfuf, Cristina; Santos, Ysabel; Muñoz-Crego, Angeles

    2013-01-24

    A new series of amino/nitro-substituted 3-arylcoumarins were synthesized and their antibacterial activity against clinical isolates of Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) was evaluated. Some of these molecules exhibited antibacterial activity against S. aureus comparable to the standards used (oxolinic acid and ampicillin). The preliminary structure-