Green synthesis of silver nanoparticles using aqueous extract of Combretum molle leaves, their antibacterial, antifungal and antioxidant activity

There are several reports on the use of the plant extracts from Combretum molle species but very limited to the extracts used effectively in the synthesis of metal nanoparticles. The present study reports on the green synthetic method in the preparation of silver nanoparticles. Combretum molle leave's extracts were used as capping as well as reducing agent. Phytochemical studies carried out on the plant leaves showed the presence of tannins, proteins, flavonoids and phenols. The effect of capping agent concentration on the size and shape of silver nanoparticles followed by the antimicrobial activity of the synthesised particles were studied. Silver nanoparticles were characterised by a combination of spectroscopic (UV-VIS, FTIR, PL), X-ray diffraction and microscopic techniques to confirm capping of the nanoparticles by the extracts. TEM results showed that the obtained particles were spherical in shape with the size ranging from 1 nm to 30 nm and they had face-centred cubic phase in their XRD patterns. The synthesised silver nanoparticle also showed slightly increased antifungal and antibacterial activity against Candida albicans, Cryptococcus neoformans, Staphylococcus aureus, Enterococcus faecalis, Klebsiella pneumonia and Pseudomonas aeruginosa as compared to the control. The MIC values obtained were between 0.20 mg/ml and 6.25 mg/ml. Copyright © 2019 Inderscience Enterprises Ltd.