Garcinia morella (Gaertn) Desr. is an annual plant widely found in the states of North-East India and the Himalayan foothills. Garcinia morella (Gaertn) Desr. fruit is known for its high phenolic content. In the present research, we explained a novel green method for the synthesis of antimicrobial silver nanoparticles (AgNPs) using the fruit extract of G. morella (Gaertn) Desr., as an effective substitution for conventional trisodium citrate. G. morella (Gaertn) Desr. mediated AgNPs with average particle size of 120 nm was found to be more effective against Bacillus subtilis MTCC 121 with MIC and MBC values 60±20 and 100±20 μg/mL respectively and against Pseudomonas aeruginosa MTCC 4673 with MIC and MBC values 80±20 and 140±20 μg/mL respectively. Citrate mediated AgNPs with average particle size of 143 nm was found to be less effective against B. subtilis MTCC 121 with MIC and MBC values 80±20 and 160±20 μL/mL respectively and against P. aeruginosa MTCC 4673 with MIC and MBC values 120±20 and 200±20 μg/mL respectively as compared to the fruit mediated AgNPs. G. morella (Gaertn) Desr. mediated AgNPs were found to be smaller in size with larger surface area as compared to that of chemically synthesized AgNPs with bigger particle size and lesser surface area and hence were found to be more effective against both gram positive and negative bacterial models. The G. morella (Gaertn) Desr. mediated AgNPs were found stable even up to 168 hr when stored at room temperature. The green method shows its novelty in terms of stability with better antimicrobial activity and also acts as a suitable substitute for sodium citrate mediated method for the synthesis of AgNPs.
Keywords: Antimicrobial activities, Bacillus subtilis, green synthesis of AgNPs, Pseudomonas aeruginosa