751
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Gade A, Ingle A, Whiteley C, Rai M. Mycogenic metal nanoparticles: progress and applications. Biotechnol Lett 2010; 32:593-600. [DOI: 10.1007/s10529-009-0197-9] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2009] [Revised: 12/14/2009] [Accepted: 12/16/2009] [Indexed: 11/30/2022]
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752
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Huang N, Lim H, Radiman S, Khiew P, Chiu W, Hashim R, Chia C. Sucrose ester micellar-mediated synthesis of Ag nanoparticles and the antibacterial properties. Colloids Surf A Physicochem Eng Asp 2010. [DOI: 10.1016/j.colsurfa.2009.10.023] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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753
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Verma VC, Kharwar RN, Gange AC. Biosynthesis of antimicrobial silver nanoparticles by the endophytic fungus Aspergillus clavatus. Nanomedicine (Lond) 2010; 5:33-40. [DOI: 10.2217/nnm.09.77] [Citation(s) in RCA: 263] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: To induce the biosynthesis of silver nanoparticles (AgNPs) using Aspergillus clavatus and evaluate their antimicrobial potential. Materials & methods: Aspergillus clavatus (AzS-275), an endophytic fungus isolated from sterilized stem tissues of Azadirachta indica A. Juss., was challenged with 1 mM AgNO3 solution. The characterization of the AgNPs was carried out by x-ray diffraction spectrometry, transmission-electron microscopy and atomic force microscopy. Results & discussion: The synthesized AgNPs were found to be extracellular, polydispersed spherical or hexagonal particles ranging from 10 to 25 nm in size. Antimicrobial activity was performed using a disc-diffusion method against Candida albicans, Pseudomonas fluorescens and Escherichia coli. The results showed an average minimum inhibitory concentration of 5.83 µg ml-1 and minimum fungicidal concentration of 9.7 µg ml-1 against C. albicans. Conclusions: AgNPs can be mycosynthesized extracellularly using A. clavatus as the fungal system, which is highly advantageous over chemical synthesis not only because it can be synthesized on a large scale, but because of the ease of downstream processing and its biomedical application in antimicrobial activity.
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Affiliation(s)
- Vijay C Verma
- Mycopathology & Microbial Technology Laboratory, Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi-221005, India
| | - Ravindra N Kharwar
- Mycopathology & Microbial Technology Laboratory, Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi-221005, India
| | - Alan C Gange
- School of Biological Sciences, Royal Holloway University of London, Egham Surrey, TW20 0EX, UK
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754
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Blue orange light emission from biogenic synthesized silver nanoparticles using Trichoderma viride. Colloids Surf B Biointerfaces 2010; 75:175-8. [DOI: 10.1016/j.colsurfb.2009.08.028] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 07/28/2009] [Accepted: 08/17/2009] [Indexed: 11/20/2022]
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755
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Tripathy A, Raichur AM, Chandrasekaran N, Prathna TC, Mukherjee A. Process variables in biomimetic synthesis of silver nanoparticles by aqueous extract of Azadirachta indica (Neem) leaves. JOURNAL OF NANOPARTICLE RESEARCH 2010; 12:237-246. [DOI: 10.1007/s11051-009-9602-5] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
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756
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Abstract
The presence of enteric viruses in drinking water is a potential health risk. Growing interest has arisen in nanometals for water disinfection, in particular the use of silver-based nanotechnology. In this study, Lactobacillus fermentum served as a reducing agent and bacterial carrier matrix for zerovalent silver nanoparticles, referred to as biogenic Ag(0). The antiviral action of biogenic Ag(0) was examined in water spiked with an Enterobacter aerogenes-infecting bacteriophage (UZ1). Addition of 5.4 mg liter(-1) biogenic Ag(0) caused a 4.0-log decrease of the phage after 1 h, whereas the use of chemically produced silver nanoparticles (nAg(0)) showed no inactivation within the same time frame. A control experiment with 5.4 mg liter(-1) ionic Ag+ resulted in a similar inactivation after 5 h only. The antiviral properties of biogenic Ag(0) were also demonstrated on the murine norovirus 1 (MNV-1), a model organism for human noroviruses. Biogenic Ag(0) was applied to an electropositive cartridge filter (NanoCeram) to evaluate its capacity for continuous disinfection. Addition of 31.25 mg biogenic Ag(0) m(-2) on the filter (135 mg biogenic Ag(0) kg(-1) filter medium) caused a 3.8-log decline of the virus. In contrast, only a 1.5-log decrease could be obtained with the original filter. This is the first report to demonstrate the antiviral efficacy of extracellular biogenic Ag(0) and its promising opportunities for continuous water disinfection.
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757
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Nanda A, Saravanan M. Biosynthesis of silver nanoparticles from Staphylococcus aureus and its antimicrobial activity against MRSA and MRSE. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2009; 5:452-6. [DOI: 10.1016/j.nano.2009.01.012] [Citation(s) in RCA: 415] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 10/25/2008] [Accepted: 01/23/2009] [Indexed: 11/29/2022]
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758
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Binupriya AR, Sathishkumar M, Yun SI. Myco-crystallization of Silver Ions to Nanosized Particles by Live and Dead Cell Filtrates of Aspergillus oryzae var. viridis and Its Bactericidal Activity toward Staphylococcus aureus KCCM 12256. Ind Eng Chem Res 2009. [DOI: 10.1021/ie9014183] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Arthur Raj Binupriya
- Department of Food Science and Technology, College of Agriculture and Life Science, Chonbuk National University, Jeonju 561-756, Korea, and Singapore−Delft Water Alliance, National University of Singapore, 2 Engineering Drive 2, Singapore 117577, Singapore
| | - Muthuswamy Sathishkumar
- Department of Food Science and Technology, College of Agriculture and Life Science, Chonbuk National University, Jeonju 561-756, Korea, and Singapore−Delft Water Alliance, National University of Singapore, 2 Engineering Drive 2, Singapore 117577, Singapore
| | - Soon-Il Yun
- Department of Food Science and Technology, College of Agriculture and Life Science, Chonbuk National University, Jeonju 561-756, Korea, and Singapore−Delft Water Alliance, National University of Singapore, 2 Engineering Drive 2, Singapore 117577, Singapore
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759
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Mohammed Fayaz A, Balaji K, Kalaichelvan P, Venkatesan R. Fungal based synthesis of silver nanoparticles—An effect of temperature on the size of particles. Colloids Surf B Biointerfaces 2009; 74:123-6. [DOI: 10.1016/j.colsurfb.2009.07.002] [Citation(s) in RCA: 199] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2009] [Revised: 06/22/2009] [Accepted: 07/06/2009] [Indexed: 11/24/2022]
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760
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Production and structural characterization of crystalline silver nanoparticles from Bacillus cereus isolate. Colloids Surf B Biointerfaces 2009; 74:191-5. [DOI: 10.1016/j.colsurfb.2009.07.016] [Citation(s) in RCA: 175] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Accepted: 07/10/2009] [Indexed: 11/19/2022]
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761
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Raghunandan D, Basavaraja S, Mahesh B, Balaji S, Manjunath SY, Venkataraman A. Biosynthesis of Stable Polyshaped Gold Nanoparticles from Microwave-Exposed Aqueous Extracellular Anti-malignant Guava (Psidium guajava) Leaf Extract. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s12030-009-9030-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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762
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Vijayakumar PS, Prasad BLV. Intracellular biogenic silver nanoparticles for the generation of carbon supported antiviral and sustained bactericidal agents. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:11741-11747. [PMID: 19746940 DOI: 10.1021/la901024p] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Intracellular silver nanoparticles produced by exposing silver ions to the fungus Aspergillus ochraceus were heat-treated in nitrogen environment to yield silver nanoparticles embedded in carbonaceous supports. This carbonaceous matrix embedded silver nanoparticles showed antimicrobial properties against both bacteria (Gram-positive and Gram-negative) and virus (M 13 phage virus). The bactericidal effects were noticed even after washing and repeated exposure of these carbon supported silver nanoparticles to fresh bacterial cultures, revealing their sustained activity.
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Affiliation(s)
- P S Vijayakumar
- Materials Chemistry Division, National Chemical Laboratory, Pune, 08, India
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763
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Korbekandi H, Iravani S, Abbasi S. Production of nanoparticles using organisms. Crit Rev Biotechnol 2009; 29:279-306. [DOI: 10.3109/07388550903062462] [Citation(s) in RCA: 200] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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764
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Barbated Skullcup herb extract-mediated biosynthesis of gold nanoparticles and its primary application in electrochemistry. Colloids Surf B Biointerfaces 2009; 73:75-9. [DOI: 10.1016/j.colsurfb.2009.04.027] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 04/29/2009] [Accepted: 04/29/2009] [Indexed: 11/20/2022]
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765
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Jia L, Zhang Q, Li Q, Song H. The biosynthesis of palladium nanoparticles by antioxidants in Gardenia jasminoides Ellis: long lifetime nanocatalysts for p-nitrotoluene hydrogenation. NANOTECHNOLOGY 2009; 20:385601. [PMID: 19713585 DOI: 10.1088/0957-4484/20/38/385601] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Gardenia jasminoides Ellis' water crude extract was used for the bioreduction of palladium chloride in this paper. The UV-vis spectrum, x-ray diffraction spectrum measurement, the Fourier transform infrared spectroscopy and TEM technique confirmed the formation of palladium nanoparticles and identified antioxidants including geniposide, chlorogenic acid, crocins and crocetin were reducing and stabilizing agents for synthesizing palladium nanoparticles in water crude extract. The particle size and dispersity were temperature-dependent. The particle sizes ranged from 3 to 5 nm and revealed the best dispersity at 70 degrees C. Catalytic performance of the biosynthetic Pd nanoparticles with good dispersity was investigated by hydrogenation of p-nitrotoluene. The catalysts showed a conversion of 100% under conditions of 5 MPa, 150 degrees C for 2 h. The selectivity of p-methyl-cyclohexylamine achieved 26.3%. The catalyst was recycled five times with no agglomeration and maintained activity, which was attributed to the appropriate protection of the antioxidants. On the basis of the study, it appears to be a new promising biosynthetic nanocatalyst for the development of an industrial process.
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Affiliation(s)
- Lishan Jia
- Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China.
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766
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Jha AK, Prasad K, Kumar V, Prasad K. Biosynthesis of silver nanoparticles using Eclipta leaf. Biotechnol Prog 2009; 25:1476-9. [DOI: 10.1002/btpr.233] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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767
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Shaligram NS, Bule M, Bhambure R, Singhal RS, Singh SK, Szakacs G, Pandey A. Biosynthesis of silver nanoparticles using aqueous extract from the compactin producing fungal strain. Process Biochem 2009. [DOI: 10.1016/j.procbio.2009.04.009] [Citation(s) in RCA: 247] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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768
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Mohammed Fayaz A, Balaji K, Girilal M, Kalaichelvan PT, Venkatesan R. Mycobased synthesis of silver nanoparticles and their incorporation into sodium alginate films for vegetable and fruit preservation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:6246-6252. [PMID: 19552418 DOI: 10.1021/jf900337h] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Biosynthesis of silver nanoparticles using Trichoderma viride and their incorporation into sodium alginate for vegetable and fruit preservation has been demonstrated in this study. Aqueous silver (Ag(+)) ions when exposed to the filtrate of T. viride are reduced in solution. These extremely stable silver nanoparticles were characterized by means of UV-vis spectrophotometer, FTIR, TEM, and EDS. The nanoparticles exhibit maximum absorbance at 421 nm in the UV spectrum. The presence of proteins was identified by FTIR. TEM micrograph revealed the formation of polydispersed nanoparticles, and the presence of elemental silver was confirmed by EDS analysis. The silver nanoparticle incorporated sodium alginate thin film shows good antibacterial activity against test strains. This film increases the shelf life of carrot and pear when compared to control with respect to weight loss and soluble protein content. These results show silver nanoparticle incorporated sodium alginate coated vegetables and fruits are suitable for preservation.
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Affiliation(s)
- A Mohammed Fayaz
- CAS in Botany, University of Madras, Guindy Campus, Chennai, India.
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769
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Gajbhiye M, Kesharwani J, Ingle A, Gade A, Rai M. Fungus-mediated synthesis of silver nanoparticles and their activity against pathogenic fungi in combination with fluconazole. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2009; 5:382-6. [PMID: 19616127 DOI: 10.1016/j.nano.2009.06.005] [Citation(s) in RCA: 319] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 05/14/2009] [Accepted: 06/15/2009] [Indexed: 10/20/2022]
Abstract
UNLABELLED Silver nanoparticles (Ag-NPs) are known to have inhibitory and bactericidal effects. Resistance of fungal infections has emerged in recent years and is a major health problem. Here, we report the extracellular biosynthesis of Ag-NPs using a common fungus, Alternaria alternata. Also in this study, these nanoparticles were evaluated for their part in increasing the antifungal activity of fluconazole against Phoma glomerata, Phoma herbarum, Fusarium semitectum, Trichoderma sp., and Candida albicans. The antifungal activity of fluconazole was enhanced against the test fungi in the presence of Ag-NPs. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, which was confirmed from the increase in fold area of inhibition, followed by P. glomerata and Trichoderma sp., which showed less increase in the fold area, whereas no significant enhancement of activity was found against P. herbarum and F. semitectum. FROM THE CLINICAL EDITOR The antifungal activity of fluconazole was enhanced in presence of silver nanoparticles against the test fungi. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, followed by P. glomerata and Trichoderma sp. No significant enhancement of activity was found against P. herbarum and F. semitectum.
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Affiliation(s)
- Monali Gajbhiye
- Department of Biotechnology, Sant Gadge Baba Amravati University, Amravati, Maharashtra, India
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770
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Wijnhoven SW, Peijnenburg WJ, Herberts CA, Hagens WI, Oomen AG, Heugens EH, Roszek B, Bisschops J, Gosens I, Van De Meent D, Dekkers S, De Jong WH, van Zijverden M, Sips AJ, Geertsma RE. Nano-silver – a review of available data and knowledge gaps in human and environmental risk assessment. Nanotoxicology 2009. [DOI: 10.1080/17435390902725914] [Citation(s) in RCA: 612] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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771
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Krumov N, Perner-Nochta I, Oder S, Gotcheva V, Angelov A, Posten C. Production of Inorganic Nanoparticles by Microorganisms. Chem Eng Technol 2009. [DOI: 10.1002/ceat.200900046] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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772
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Bhambure R, Bule M, Shaligram N, Kamat M, Singhal R. Extracellular Biosynthesis of Gold Nanoparticles using Aspergillus niger - its Characterization and Stability. Chem Eng Technol 2009. [DOI: 10.1002/ceat.200800647] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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773
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Lactic acid bacteria as reducing and capping agent for the fast and efficient production of silver nanoparticles. Appl Microbiol Biotechnol 2009; 84:741-9. [DOI: 10.1007/s00253-009-2032-6] [Citation(s) in RCA: 268] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 04/30/2009] [Accepted: 05/01/2009] [Indexed: 11/25/2022]
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774
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Perner-Nochta I, Krumov N, Oder S, Posten C, Angelov A. Biopartikel: Eine Alternative zur Produktion nanoskaliger anorganischer Partikel. CHEM-ING-TECH 2009. [DOI: 10.1002/cite.200900035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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775
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Kathiresan K, Manivannan S, Nabeel M, Dhivya B. Studies on silver nanoparticles synthesized by a marine fungus, Penicillium fellutanum isolated from coastal mangrove sediment. Colloids Surf B Biointerfaces 2009; 71:133-7. [DOI: 10.1016/j.colsurfb.2009.01.016] [Citation(s) in RCA: 433] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Accepted: 01/22/2009] [Indexed: 11/30/2022]
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776
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Begum NA, Mondal S, Basu S, Laskar RA, Mandal D. Biogenic synthesis of Au and Ag nanoparticles using aqueous solutions of Black Tea leaf extracts. Colloids Surf B Biointerfaces 2009; 71:113-8. [DOI: 10.1016/j.colsurfb.2009.01.012] [Citation(s) in RCA: 377] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Revised: 12/17/2008] [Accepted: 01/13/2009] [Indexed: 11/29/2022]
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777
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Fayaz AM, Balaji K, Girilal M, Yadav R, Kalaichelvan PT, Venketesan R. Biogenic synthesis of silver nanoparticles and their synergistic effect with antibiotics: a study against gram-positive and gram-negative bacteria. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2009; 6:103-9. [PMID: 19447203 DOI: 10.1016/j.nano.2009.04.006] [Citation(s) in RCA: 671] [Impact Index Per Article: 44.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2008] [Revised: 03/05/2009] [Accepted: 04/23/2009] [Indexed: 10/20/2022]
Abstract
UNLABELLED The development of a reliable green chemistry process for the biogenic synthesis of nanomaterials is an important aspect of current nanotechnology research. Silver nanoparticles (AgNPs) have been known for their inhibitory and bactericidal effect. Resistance to antimicrobial agents by pathogenic bacteria has emerged in recent years and is a major challenge for the health care industry. In the present investigation the use of the fungus Trichoderma viride for the extracellular biosynthesis of AgNPs from silver nitrate solution is reported. It was observed that the aqueous silver (Ag(+)) ions, when exposed to a filtrate of T. viride, were reduced in solution, thereby leading to formation of extremely stable AgNPs. These AgNPs were characterized by means of several techniques. The nanoparticles show maximum absorbance at 420 nm on ultraviolet-visible spectra. The presence of proteins was identified by Fourier transform-infrared spectroscopy. The reduction of Ag(+) ions to elemental silver was characterized by x-ray photoelectron spectrophotometry. Electrokinetic measurements (zeta potential) of AgNPs as a function of pH in 1 x 10(-3) mol dm(-3) aqueous solution were evaluated. The transmission electron micrograph revealed the formation of polydispersed nanoparticles of 5-40 nm, and the presence of elemental silver was confirmed by energy-dispersed spectroscopy analysis. The nanoparticles were also evaluated for their increased antimicrobial activities with various antibiotics against gram-positive and gram-negative bacteria. The antibacterial activities of ampicillin, kanamycin, erythromycin, and chloramphenicol were increased in the presence of AgNPs against test strains. The highest enhancing effect was observed for ampicillin against test strains. The result showed that the combination of antibiotics with AgNPs have better antimicrobial effects. A mechanism was also proposed to explain this phenomenon. FROM THE CLINICAL EDITOR Silver nanoparticles (Ag NP-s) represent an important nanomedicine-based advance in the fight against polyresistent bacteria. In this study, the fungus Trichoderma viride was utilized for extracellular biosynthesis of extremely stable Ag Nps. The antibacterial activities of kanamycin, erythromycin, chloramphenicol and especially of ampicillin were increased in the presence of Ag NPs against test strains.
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778
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Jia X, Qian W, Wu D, Wei D, Xu G, Liu X. Cuttlebone-derived organic matrix as a scaffold for assembly of silver nanoparticles and application of the composite films in surface-enhanced Raman scattering. Colloids Surf B Biointerfaces 2009; 68:231-7. [DOI: 10.1016/j.colsurfb.2008.10.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Revised: 10/14/2008] [Accepted: 10/15/2008] [Indexed: 10/21/2022]
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779
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Sharma VK, Yngard RA, Lin Y. Silver nanoparticles: green synthesis and their antimicrobial activities. Adv Colloid Interface Sci 2009; 145:83-96. [PMID: 18945421 DOI: 10.1016/j.cis.2008.09.002] [Citation(s) in RCA: 1730] [Impact Index Per Article: 115.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 08/23/2008] [Accepted: 09/01/2008] [Indexed: 11/28/2022]
Abstract
This review presents an overview of silver nanoparticles (Ag NPs) preparation by green synthesis approaches that have advantages over conventional methods involving chemical agents associated with environmental toxicity. Green synthetic methods include mixed-valence polyoxometallates, polysaccharide, Tollens, irradiation, and biological. The mixed-valence polyoxometallates method was carried out in water, an environmentally-friendly solvent. Solutions of AgNO(3) containing glucose and starch in water gave starch-protected Ag NPs, which could be integrated into medical applications. Tollens process involves the reduction of Ag(NH(3))(2)(+) by saccharides forming Ag NP films with particle sizes from 50-200 nm, Ag hydrosols with particles in the order of 20-50 nm, and Ag colloid particles of different shapes. The reduction of Ag(NH(3))(2)(+) by HTAB (n-hexadecyltrimethylammonium bromide) gave Ag NPs of different morphologies: cubes, triangles, wires, and aligned wires. Ag NPs synthesis by irradiation of Ag(+) ions does not involve a reducing agent and is an appealing procedure. Eco-friendly bio-organisms in plant extracts contain proteins, which act as both reducing and capping agents forming stable and shape-controlled Ag NPs. The synthetic procedures of polymer-Ag and TiO(2)-Ag NPs are also given. Both Ag NPs and Ag NPs modified by surfactants or polymers showed high antimicrobial activity against gram-positive and gram-negative bacteria. The mechanism of the Ag NP bactericidal activity is discussed in terms of Ag NP interaction with the cell membranes of bacteria. Silver-containing filters are shown to have antibacterial properties in water and air purification. Finally, human and environmental implications of Ag NPs to the ecology of aquatic environment are briefly discussed.
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Affiliation(s)
- Virender K Sharma
- Chemistry Department, Florida Institute of Technology, 150 West University Boulevard, Melbourne, Florida 32901, USA.
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780
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Extracellular biosynthesis of functionalized silver nanoparticles by strains of Cladosporium cladosporioides fungus. Colloids Surf B Biointerfaces 2009; 68:88-92. [DOI: 10.1016/j.colsurfb.2008.09.022] [Citation(s) in RCA: 428] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2008] [Revised: 08/30/2008] [Accepted: 09/16/2008] [Indexed: 11/21/2022]
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781
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Sanghi R, Verma P. Biomimetic synthesis and characterisation of protein capped silver nanoparticles. BIORESOURCE TECHNOLOGY 2009; 100:501-4. [PMID: 18625550 DOI: 10.1016/j.biortech.2008.05.048] [Citation(s) in RCA: 245] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 05/20/2008] [Accepted: 05/22/2008] [Indexed: 05/24/2023]
Abstract
A controlled and up-scalable route for the biosynthesis of silver nanopartilces (NPs) mediated by fungal proteins of Coriolus versicolor has been undertaken for the first time. The fungus when challenged with silver nitrate solution accumulated silver NPs on its surface in 72h which could be reduced to 1h by tailoring the reaction conditions. Under alkaline conditions, the reaction was much faster and could easily proceed at room temperature even without stirring. The resulting Ag NPs displayed controllable structural and optical properties depending on the experimental parameters such as pH and reaction temperatures. The average size, morphology, and structure of particles were determined by AFM, TEM, XRD and UV/Visible absorption spectrophotometry. Fourier transform infrared study disclosed that the amino groups were bound to the particles, which was accountable for the stability of NPs. It further confirmed the presence of protein as the stabilizing and capping agent surrounding the silver NPs. Experiments were conducted both with, media in which fungus was initially harvested and that of pristine fungal mycelium alone. Under normal conditions, in the case of media extracellular synthesis took place whereby other than the fungal proteins, glucose was also responsible for the reduction. In the case of fungal mycelium, the intracellular formation of Ag NPs, could be tailored to give both intracellular and extracellular Ag NPs under alkaline conditions whereby the surface S-H groups of the fungus played a major role.
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Affiliation(s)
- Rashmi Sanghi
- Facility for Ecological and Analytical Testing, Indian Institute of Technology Kanpur, Kanpur, India.
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782
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Patra CR, Cao S, Safgren S, Bhattacharya R, Ames MM, Shah V, Reid JM, Mukherjee P. Intracellular Fate of a Targeted Delivery System. J Biomed Nanotechnol 2008. [DOI: 10.1166/jbn.2008.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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783
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Direct formation of silver nanoparticles in cuttlebone-derived organic matrix for catalytic applications. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2008.08.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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784
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Abstract
There is a growing need to develop clean, nontoxic and environmentally friendly ("green chemistry") procedures for synthesis and assembly of nanoparticles. The use of biological organisms in this area is rapidly gaining importance due to its growing success and ease of formation of nanoparticles. Presently, the potential of bio-organisms ranges from simple prokaryotic bacterial cells to eukaryotic fungus and even live plants. In this article we have reviewed some of these biological systems, which have revolutionized the art of nano-material synthesis.
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785
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Navarro E, Baun A, Behra R, Hartmann NB, Filser J, Miao AJ, Quigg A, Santschi PH, Sigg L. Environmental behavior and ecotoxicity of engineered nanoparticles to algae, plants, and fungi. ECOTOXICOLOGY (LONDON, ENGLAND) 2008; 17:372-86. [PMID: 18461442 DOI: 10.1007/s10646-008-0214-0] [Citation(s) in RCA: 816] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Accepted: 04/14/2008] [Indexed: 05/20/2023]
Abstract
Developments in nanotechnology are leading to a rapid proliferation of new materials that are likely to become a source of engineered nanoparticles (ENPs) to the environment, where their possible ecotoxicological impacts remain unknown. The surface properties of ENPs are of essential importance for their aggregation behavior, and thus for their mobility in aquatic and terrestrial systems and for their interactions with algae, plants and, fungi. Interactions of ENPs with natural organic matter have to be considered as well, as those will alter the ENPs aggregation behavior in surface waters or in soils. Cells of plants, algae, and fungi possess cell walls that constitute a primary site for interaction and a barrier for the entrance of ENPs. Mechanisms allowing ENPs to pass through cell walls and membranes are as yet poorly understood. Inside cells, ENPs might directly provoke alterations of membranes and other cell structures and molecules, as well as protective mechanisms. Indirect effects of ENPs depend on their chemical and physical properties and may include physical restraints (clogging effects), solubilization of toxic ENP compounds, or production of reactive oxygen species. Many questions regarding the bioavailability of ENPs, their uptake by algae, plants, and fungi and the toxicity mechanisms remain to be elucidated.
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Affiliation(s)
- Enrique Navarro
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Ueberlandstrasse 133, Dubendorf 8600, Switzerland.
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786
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Kalimuthu K, Suresh Babu R, Venkataraman D, Bilal M, Gurunathan S. Biosynthesis of silver nanocrystals by Bacillus licheniformis. Colloids Surf B Biointerfaces 2008; 65:150-3. [PMID: 18406112 DOI: 10.1016/j.colsurfb.2008.02.018] [Citation(s) in RCA: 459] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Revised: 02/22/2008] [Accepted: 02/22/2008] [Indexed: 11/18/2022]
Abstract
The use of microorganisms for the synthesis of nanoparticles is in the limelight of modern nanotechnology. Using the bacterium Bacillus licheniformis, the biosynthesis of silver nanoparticles was investigated. These silver nanoparticles were characterized by means of UV-vis spectroscopy, scanning electron microscopy (SEM), electron diffraction spectroscopy (EDX) and X-ray diffraction (XRD). The nanoparticles exhibited maximum absorbance at 440 nm in UV-vis spectroscopy. The XRD spectrum of silver nanoparticles exhibited 2theta values corresponding to the silver nanocrystal. SEM micrographs revealed the formation of well-dispersed silver nanoparticles of 50 nm, and the presence of silver was confirmed by EDX analysis.
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Affiliation(s)
- Kalishwaralal Kalimuthu
- Department of Biotechnology, Kalasalingam University, Anand Nagar, Krishnankoil 626190, Tamilnadu, India
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787
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Mukherjee P, Roy M, Mandal BP, Dey GK, Mukherjee PK, Ghatak J, Tyagi AK, Kale SP. Green synthesis of highly stabilized nanocrystalline silver particles by a non-pathogenic and agriculturally important fungus T. asperellum. NANOTECHNOLOGY 2008; 19:075103. [PMID: 21817628 DOI: 10.1088/0957-4484/19/7/075103] [Citation(s) in RCA: 225] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A controlled and up-scalable biosynthetic route to nanocrystalline silver particles with well-defined morphology using cell-free aqueous filtrate of a non-pathogenic and commercially viable biocontrol agent Trichoderma asperellum is being reported for the first time. A transparent solution of the cell-free filtrate of Trichoderma asperellum containing 1 mM AgNO(3) turns progressively dark brown within 5 d of incubation at 25 °C. The kinetics of the reaction was studied using UV-vis spectroscopy. An intense surface plasmon resonance band at ∼410 nm in the UV-vis spectrum clearly reveals the formation of silver nanoparticles. The size of the silver particles using TEM and XRD studies is found to be in the range 13-18 nm. These nanoparticles are found to be highly stable and even after prolonged storage for over 6 months they do not show significant aggregation. A plausible mechanism behind the formation of silver nanoparticles and their stabilization via capping has been investigated using FTIR and surface-enhanced resonance Raman spectroscopy.
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Affiliation(s)
- P Mukherjee
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai 400085, India
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788
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Xie J, Lee JY, Wang DIC, Ting YP. Silver nanoplates: from biological to biomimetic synthesis. ACS NANO 2007; 1:429-39. [PMID: 19206664 DOI: 10.1021/nn7000883] [Citation(s) in RCA: 325] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
This paper describes the synthesis of single-crystalline Ag nanoplates using the extract of unicellular green alga Chlorella vulgaris at room temperature. Proteins in the extract were involved in the biological synthesis, providing the dual function of Ag ion reduction and shape-controlled synthesis of nanosilver. Hydroxyl groups in Tyr residues and carboxyl groups in Asp and/or Glu residues were further identified as the most active functional groups for Ag ion reduction and for directing the anisotropic growth of Ag nanoplates, respectively. The kinetics of Ag ion reduction in biological systems was discussed and probed by using custom-designed peptides. The results showed the Tyr content (the reduction source) and the content of Ag complexers (the reaction inhibitors, e.g., His and Cys) in the protein molecules as important factors affecting the reduction kinetics. The comprehensive system identification effort has led to the design of a simple bifunctional tripeptide (DDY-OMe) with one Tyr residue as the reduction source and two carboxyl groups in the Asp residues as shape-directors, which could produce small Ag nanoplates with low polydispersivity in good yield (>55%). The roles of the carboxyl groups in the formation of Ag nanoplates were also discussed.
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Affiliation(s)
- Jianping Xie
- Singapore-MIT Alliance, 4 Engineering Drive 3, National University of Singapore, Singapore 117576
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789
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Zhang H, Li Q, Wang H, Sun D, Lu Y, He N. Accumulation of Silver(I) Ion and Diamine Silver Complex by Aeromonas SH10 biomass. Appl Biochem Biotechnol 2007; 143:54-62. [DOI: 10.1007/s12010-007-8006-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Revised: 11/30/1999] [Accepted: 05/25/2007] [Indexed: 11/28/2022]
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790
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Vigneshwaran N, Kathe AA, Varadarajan PV, Nachane RP, Balasubramanya RH. Silver-protein (core-shell) nanoparticle production using spent mushroom substrate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:7113-7. [PMID: 17518485 DOI: 10.1021/la063627p] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
A simple route for the synthesis of silver-protein (core-shell) nanoparticles using spent mushroom substrate (SMS) has been demonstrated in this work. SMS exhibits an organic surface that reduces silver ions and stabilizes the silver nanoparticles by a secreted protein. The silver nitrate solution incubated with SMS changed to a yellow color from 24 h onward, indicating the formation of silver nanoparticles. The purified solution yielded the maximum absorbance at 436 nm due to surface plasmon resonance of the silver nanoparticles. X-ray analysis of the freeze-dried powder of silver nanoparticles confirmed the formation of metallic silver. Transmission electron microscopic analysis of the samples showed a uniform distribution of nanoparticles, having an average size of 30.5 +/- 4.0 nm, and its corresponding electron diffraction pattern confirmed the face-centered cubic (fcc) crystalline structure of metallic silver. The characteristic fluorescence of the protein shell at 435 nm was observed for the silver nanoparticles in solution, when excited at 280 nm, while Fourier transform infrared (FTIR) spectroscopy confirmed the presence of a protein shell. The silver nanoparticles were found to be stable in solution for more than 6 months. It is observed that the reducing agents from the safflower stalks caused the reduction of silver ions while protein secreted by the fungus stabilized the silver nanoparticles. These silver nanoparticles showed excellent antibacterial activity against two representative bacteria, Staphylococcus aureus (Gram positive) and Klebsiella pneumoniae (Gram negative), in spite of the presence of an organic layer as a shell. Apart from ecofriendliness and easy availability, "SMS" as a biomanufacturing unit will give us an added advantage in ease of handling when compared to other classes of microorganisms.
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Affiliation(s)
- Nadanathangam Vigneshwaran
- Nanotechnology Research Group, Central Institute for Research on Cotton Technology, Adenwala Road, Matunga, Mumbai 400 019, India.
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791
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Singaravelu G, Arockiamary JS, Kumar VG, Govindaraju K. A novel extracellular synthesis of monodisperse gold nanoparticles using marine alga, Sargassum wightii Greville. Colloids Surf B Biointerfaces 2007; 57:97-101. [PMID: 17350236 DOI: 10.1016/j.colsurfb.2007.01.010] [Citation(s) in RCA: 261] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2006] [Revised: 01/18/2007] [Accepted: 01/18/2007] [Indexed: 11/30/2022]
Abstract
The process of development of reliable and eco-friendly metallic nanoparticles is an important step in the field of nanotechnology. To achieve this use of natural sources like biological systems becomes essential. In the present, work we have investigated extracellular biosynthesis of gold nanoparticles using Sargassum wightii and have achieved rapid formation of gold nanoparticles in a short duration. The UV-vis spectrum of the aqueous medium containing gold ion showed peak at 527 nm corresponding to the plasmon absorbance of gold nanoparticles. Transmission electron microscopy (TEM) showed formation of well-dispersed gold nanoparticles in the range of 8-12 nm. X-ray diffraction (XRD) spectrum of the gold nanoparticles exhibited Bragg reflections corresponding to gold nanoparticles.
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Affiliation(s)
- G Singaravelu
- Department of Zoology, Thiruvalluvar University, Vellore 632004, India.
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792
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Shahverdi AR, Minaeian S, Shahverdi HR, Jamalifar H, Nohi AA. Rapid synthesis of silver nanoparticles using culture supernatants of Enterobacteria: A novel biological approach. Process Biochem 2007. [DOI: 10.1016/j.procbio.2007.02.005] [Citation(s) in RCA: 299] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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793
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Du L, Jiang H, Liu X, Wang E. Biosynthesis of gold nanoparticles assisted by Escherichia coli DH5α and its application on direct electrochemistry of hemoglobin. Electrochem commun 2007. [DOI: 10.1016/j.elecom.2007.01.007] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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794
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Synthesis and effect of silver nanoparticles on the antibacterial activity of different antibiotics against Staphylococcus aureus and Escherichia coli. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2007; 3:168-71. [PMID: 17468052 DOI: 10.1016/j.nano.2007.02.001] [Citation(s) in RCA: 655] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Revised: 12/26/2006] [Accepted: 02/08/2007] [Indexed: 11/29/2022]
Abstract
Silver nanoparticles (Ag-NPs) have been known to have inhibitory and bactericidal effects. Resistance to antimicrobial agents by pathogenic bacteria has emerged in recent years and is a major health problem. The combination effects of Ag-NPs with the antibacterial activity of antibiotics have not been studied. Here, we report on the synthesis of metallic nanoparticles of silver using a reduction of aqueous Ag(+) ion with the culture supernatants of Klebsiella pneumoniae. Also in this article these nanoparticles are evaluated for their part in increasing the antimicrobial activities of various antibiotics against Staphylococcus aureus and Escherichia coli. The antibacterial activities of penicillin G, amoxicillin, erythromycin, clindamycin, and vancomycin were increased in the presence of Ag-NPs against both test strains. The highest enhancing effects were observed for vancomycin, amoxicillin, and penicillin G against S. aureus.
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795
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Anil Kumar S, Abyaneh MK, Gosavi SW, Kulkarni SK, Pasricha R, Ahmad A, Khan MI. Nitrate reductase-mediated synthesis of silver nanoparticles from AgNO3. Biotechnol Lett 2007; 29:439-45. [PMID: 17237973 DOI: 10.1007/s10529-006-9256-7] [Citation(s) in RCA: 309] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Revised: 10/27/2006] [Accepted: 10/30/2006] [Indexed: 11/26/2022]
Abstract
Synthesis of silver nanoparticles using alpha-NADPH-dependent nitrate reductase and phytochelatin in vitro has been demonstrated for the first time. The silver ions were reduced in the presence of nitrate reductase, leading to the formation of a stable silver hydrosol 10-25 nm diam. and stabilized by the capping peptide. The nanoparticles were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and UV-Vis absorption. These studies will help in designing a rational enzymatic strategy for the synthesis of nanomaterials of different chemical composition, shapes and sizes as well as their separation.
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Affiliation(s)
- S Anil Kumar
- Biochemical Sciences Division, National Chemical Laboratory, Pune, India
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796
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Thilakaraj R, Raghunathan K, Anishetty S, Pennathur G. In silico identification of putative metal binding motifs. Bioinformatics 2006; 23:267-71. [PMID: 17148509 DOI: 10.1093/bioinformatics/btl617] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Metal ion binding domains are found in proteins that mediate transport, buffering or detoxification of metal ions. In this study, we have performed an in silico analysis of metal binding proteins and have identified putative metal binding motifs for the ions of cadmium, cobalt, zinc, arsenic, mercury, magnesium, manganese, molybdenum and nickel. A pattern search against the UniProtKB/Swiss-Prot and UniProtKB/TrEMBL databases yielded true positives in each case showing the high-specificity of the motifs. Motifs were also validated against PDB structures and site directed mutagenesis studies.
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797
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Yang L, Shen Y, Xie A, Liang J, Li S, Zhang Q. Size- and Shape-Controlled Synthesis and Assembly of a Silver Nanocomplex in UV-Irradiated TSA Solution. Eur J Inorg Chem 2006. [DOI: 10.1002/ejic.200600621] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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798
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Vigneshwaran N, Kathe AA, Varadarajan PV, Nachane RP, Balasubramanya RH. Biomimetics of silver nanoparticles by white rot fungus, Phaenerochaete chrysosporium. Colloids Surf B Biointerfaces 2006; 53:55-9. [PMID: 16962745 DOI: 10.1016/j.colsurfb.2006.07.014] [Citation(s) in RCA: 163] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 07/21/2006] [Accepted: 07/21/2006] [Indexed: 11/24/2022]
Abstract
Extracellular synthesis of silver nanoparticles by a white rot fungus, Phaenerochaete chrysosporium is reported in this paper. Incubation of P. chrysosporium mycelium with silver nitrate solution produced silver nanoparticles in 24h. These silver nanoparticles were characterized by means of UV-vis spectroscopy, X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The synthesized silver nanoparticles absorbed maximum at 470 nm in the visible region. XRD spectrum of the silver nanoparticles confirmed the formation of metallic silver. The SEM characterization of the fungus reacted on the Ag+ indicated that the protein might be responsible for the stabilization of silver nanoparticles. This result was further supported by the TEM examination. Though shape variation was noticed, majority of the nanoparticles were found to be of pyramidal shape as seen under TEM. Photoluminescence spectrum showed a broad emission peak of silver nanoparticles at 423 nm when excited at 350 nm. Apart from eco-friendliness, fungus as bio-manufacturing unit will give us an added advantage in ease of handling when compared to other classes of microorganisms.
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Affiliation(s)
- Nadanathangam Vigneshwaran
- Nanotechnology Research Group, Central Institute for Research on Cotton Technology, Adenwala Road, Matunga, Mumbai, Maharastra 400019, India.
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799
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800
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Dawn A, Nandi AK. Formation of Silver Nanoparticles in Deoxyribonucleic Acid−Poly(o-methoxyaniline) Hybrid: A Novel Nano-biocomposite. J Phys Chem B 2006; 110:18291-8. [PMID: 16970449 DOI: 10.1021/jp063269z] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel nano-biocomposite of silver and poly(o-methoxy aniline) (POMA)/DNA hybrid has been prepared by adding DNA solution to an aqueous solution of POMA (emeraldine base, EB) and AgNO(3) mixture. The mixture was aged for 10 days and was freeze-dried to form the hybrid nanocomposite (weight fraction of DNA = 0.75). FESEM pictures show a fibrillar network morphology of the biomolecular hybrid with silver nanoparticles on its surface. The TEM picture also corroborates silver nanoparticle formation in the biomolecular hybrid, and the denser population of nanoparticles in the TEM micrograph as compared to that in the SEM micrograph indicates that the nanoparticles are present inside the fibrils in greater proportion. The dc conductivity value of the hybrid indicates that POMA (EB) is doped by silver ion and the doped POMA form complexes with DNA through electrostatic interaction of the radical cation of POMA (emeraldine salt form, ES) and the DNA anion. During the doping process and Ag nanoparticle formation, a fluctuation of the pi band to polaron band transition peak occurs together with a complementary fluctuation of the polaron band to pi* band transition peak. After 53 h of aging, the former shows a slow but continuous red shift with aging time. This has been attributed to the slow uncoiling of POMA on the DNA surface. The conformation and crystal structure of DNA remain intact during the nano-biocomposite formation. The dc conductivity value of the nano-biocomposite is almost the same as that of the pure POMA-DNA hybrid at the same composition, but the I-V characteristic curve of the nano-biocomposite is somewhat different showing an insulating region on low applied voltage. At higher applied voltage, it shows a semiconducting property characterizing the large band gap semiconducting behavior of the nano-biocomposite.
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Affiliation(s)
- Arnab Dawn
- Polymer Science Unit, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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