Silver nanoparticles are applied in nanomedicine from time immemorial and are still used as powerful antibiotic and anti-inflammatory agents. Antibiotics produced by actinomycetes are popular in almost all the therapeutic measures, and this study has proven that these microbes are also helpful in the biosynthesis of silver nanoparticles with good surface and size characteristics. Silver can be synthesized by various chemical methodologies, and most of them have turned to be toxic. This study has been successful in isolating the microbes from polluted environment, and subjecting them to the reduction of silver nanoparticles, characterizing the nanoparticles by UV spectrophotometry and transmission electron microscopy. The nanoparticles produced were tested for their antimicrobial property, and the zone of inhibition was greater than those produced by their chemically synthesized counterparts. Actinomycetes, helpful in bioremediating heavy metals, are useful for the production of metallic nanoparticles. The biosynthesized silver nanoparticles loaded with antibiotics prove to be better in killing the pathogens and have opened up new areas for developing nanobiotechnological research based on microbial applications. 1. Introduction Human activities are greatly altering ecosystems worldwide at unprecedented rates, leading to accelerated loss of biodiversity [1] and environmental pollution. Soil is perhaps the most endangered component of our environment being open to potential contamination by a variety of different pollutants arising from human activities such as nuclear, industrial, and activities agricultural, [2, 3]. There are hundreds of sources of heavy metal pollution, including the coal, natural gas, paper, and chloralkali industries [4]. “Heavy metals” is a general collective term, which applies to the group of metals and metalloids with atomic density greater than 4？g/cm3, or 5 times or more, greater than water [5–7]. Microorganisms in the soil are responsible for nitrogen fixation, assimilation, and degradation of organic residues to release nutrients. Field studies of metal contaminated soils have demonstrated that elevated metal loadings can result in decreased microbial community [8–11]. Actinomycetes populations are relatively lower than other soil microbes and contain a predominance of streptomyces that are tolerant to acid conditions [12]. Classically the nanoparticles are produced by physical and chemical methods [13]. But these methods are costly, toxic, and nonecofriendly. Currently, there is a growing need to use environmentally friendly
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