Green synthesis of silver nanoparticles using Azadirachta indica leaf extract and its antimicrobial study

Abstract

In this study, green synthesis of silver nanoparticles was done using leaf extracts of Azadirachta indica. The flavonoids and terpenoids present in the extract act as both reducing and capping agent. Microbes (Escherichia coli and Gram-positive bacteria) were isolated from borewell water using selective media. The silver nanoparticles showed antimicrobial activities against Gram-positive bacteria and E. coli. However the silver nanoparticles were more effective against E. coli as compared to Gram-positive bacteria. Various techniques were used to characterize synthesized silver nanoparticles such as DLS and UVvisible spectrophotometer. The absorbance peak was in the range of 420-450 nm, that varied depending upon the variation in the concentration of neem extract. This is a very rapid and cost-effective method for generation of silver nanoparticle at room temperature, however, its exact dose in water purification has to be determined.

Synthesis of silver nanoparticles using flavonoids: hesperidin, naringin and diosmin, and their antibacterial effects and cytotoxicity

“…When Ag ? ions come in contact with -O-H groups, the white colloidal particles of AgOH are formed which turns to brown colored Ag nanoparticles after exposing the solution to bright sunlight due to surface plasmon resonance effect [21]. Transmission Electron Microscope was used for size determination of synthesized silver nanoparticles.…”

Coupled Oxides/LLDPE Composites for Textile Effluent Treatment: Effect of Neem and PVA Stabilization

“…(Figure 2b). Theoretically, azadirachtin is a major component of neem [16] that contain active ingredients of limonoids. The generalized structure of this component is shown in Figure 3, which indicate the presence of abundant hydroxyl (OH) and carbonyl (C=O) groups.…”

“…Recently, neem extracts were used in the green-synthesis of various nanoparticles like silver, ZnO, gold, etc. [14][15][16][17][18]. This is due to the phytochemicals that are present in the extract.…”

Green synthesis of silver nanoparticles using cauliflower waste and their multifaceted applications in photocatalytic degradation of methylene blue dye and Hg2+ biosensing

“…Colloidal silver particles have been reported to act as effective antimicrobial agents against bacteria and viruses [11,[13][14][15]. They also possess promising catalytic activity, which enable them to degrade harmful synthetic dyes such as methylene blue (MB), congo red, methyl orange and methyl red [2,3,11,[16][17][18][19].…”