Silver nanoparticles are considerecl as good antimicrobial agent. AgNPs were synthesized by mixing silver nitrate solution with citrus sinesb extract for 2 h at 37 and analyzed by UV-visible spectra, SEM, XRD, and FT...Silver nanoparticles are considerecl as good antimicrobial agent. AgNPs were synthesized by mixing silver nitrate solution with citrus sinesb extract for 2 h at 37 and analyzed by UV-visible spectra, SEM, XRD, and FTIR. AgNPs were tested against B. subtilis, Shigello, S. oureus, ond E. coli. Minimum inhibitory concentration of AgNPs was 20 I^g/mL for B. subtilis and Shigello and 30 I^g/mL for S. oureus and E. coll. Antibiofilm activity （80% to 90%） was observed at 25 IJg/mL. AgNPs were stable for five months with sustained an＇timicrobial activity. Biosynthesized AgNPs can bE： used to inhibit food poisoning microbial growth.展开更多
Biorecycling microbes, which have critical functionalities in natural cycles, are essential to sustain eco-system of the earth. Any alterations in these cycles caused by the mutations of microbes could be a potential ...Biorecycling microbes, which have critical functionalities in natural cycles, are essential to sustain eco-system of the earth. Any alterations in these cycles caused by the mutations of microbes could be a potential threat to life on earth. Antibiotics leached from pharmaceutical waste, animal food and agribusiness prod- ucts are accumulating in the environment. Metal nanoparticles are also accumulating in environment because of their extensive use as biocidal agent in domestic products. Interaction of antibiotics and metal nanoparticles with eco-ffiendly microorganisms has a potential to alter the ecosystem of the earth. In this article, we have studied the antibacterial activities of silver and copper nanoparticles and their for- mulations with antibiotics, tetracycline, and kanamycin against biorecycling microbes, Bacillus subtilis and Pseudomonas fluorescens. Strong synergistic effect of metal nanoparticles on the antimicrobial ac- tivities of commercial antibiotics has been observed. Antimicrobial activity of tetracycline improves by 286%-346% and 0%-28% when being tested in the presence of 250 ppm of silver and copper nanoparticles, respectively. For kanamycin, the improvement is 154%-289% for silver and 3%-20% for copper nanoparticles. Irrespective of the antibiotics and tested organisms, synergy is more prominent for silver nanoparticles even at their minimum active concentration （100 ppm）. This study demonstrates that the combination of metal nanoparticles with antibiotics could be more fatal to ecosystem than either the metal nanoparticles or the antibiotics alone.展开更多
文摘Silver nanoparticles are considerecl as good antimicrobial agent. AgNPs were synthesized by mixing silver nitrate solution with citrus sinesb extract for 2 h at 37 and analyzed by UV-visible spectra, SEM, XRD, and FTIR. AgNPs were tested against B. subtilis, Shigello, S. oureus, ond E. coli. Minimum inhibitory concentration of AgNPs was 20 I^g/mL for B. subtilis and Shigello and 30 I^g/mL for S. oureus and E. coll. Antibiofilm activity （80% to 90%） was observed at 25 IJg/mL. AgNPs were stable for five months with sustained an＇timicrobial activity. Biosynthesized AgNPs can bE： used to inhibit food poisoning microbial growth.
基金financially supported by the University Grants Commission,New Delhi(scheme No.F.No.42-850/2013(SR))
文摘Biorecycling microbes, which have critical functionalities in natural cycles, are essential to sustain eco-system of the earth. Any alterations in these cycles caused by the mutations of microbes could be a potential threat to life on earth. Antibiotics leached from pharmaceutical waste, animal food and agribusiness prod- ucts are accumulating in the environment. Metal nanoparticles are also accumulating in environment because of their extensive use as biocidal agent in domestic products. Interaction of antibiotics and metal nanoparticles with eco-ffiendly microorganisms has a potential to alter the ecosystem of the earth. In this article, we have studied the antibacterial activities of silver and copper nanoparticles and their for- mulations with antibiotics, tetracycline, and kanamycin against biorecycling microbes, Bacillus subtilis and Pseudomonas fluorescens. Strong synergistic effect of metal nanoparticles on the antimicrobial ac- tivities of commercial antibiotics has been observed. Antimicrobial activity of tetracycline improves by 286%-346% and 0%-28% when being tested in the presence of 250 ppm of silver and copper nanoparticles, respectively. For kanamycin, the improvement is 154%-289% for silver and 3%-20% for copper nanoparticles. Irrespective of the antibiotics and tested organisms, synergy is more prominent for silver nanoparticles even at their minimum active concentration （100 ppm）. This study demonstrates that the combination of metal nanoparticles with antibiotics could be more fatal to ecosystem than either the metal nanoparticles or the antibiotics alone.
