Synthesis of Bio-Inspired Silver Nanoparticles by Ripe and Unripe Fruit Extract of Tinospora cordifolia and Its Antioxidant, Antibacterial and Catalytic Studies

Green synthesis of silver nanoparticles (Ag NPs) by both ripe and unripe fruit extract was carried out by an important medicinal plant Tinospora cordifolia. The ripe and unripe fruit extract mediated bio-inspired Ag NPs showed surface plasmon resonance (SPR) band at 431 and 421 nm respectively and confirmed the formation of Tc-Ag NPs. The functional groups of bioactive components of ripe and unripe fruits were identified which reduced silver nitrate to silver ions by Fourier-transform infrared spectroscopy (FTIR). The size distribution of biosynthesized Tc-Ag NPs of ripe and unripe was determined by particle size analyzer which revealed that the Z average of Tc-Ag NPs was around 30 - 35 nm  ± 1 nm and 30 - 35.8 nm ± 1 nm with an Z average of 25.9 and 28.5 nm respectively. Tc-Ag NPs exhibited stability due to its high negative zeta potential for both ripe and unripe fruit extract mediated Tc-Ag NPs as of -27.2 and -24.6 mV. Tc-Ag NPs were used to evaluate the antibacterial, antioxidant and catalytic activities. The Tc-Ag NPs revealed good antimicrobial activity. Antibiotic erythromycin was used as a standard in the present study. The Tc-Ag NPs of both ripe and unrippen fruits disclosed greater free radical scavenging efficacy which proved to be potent antioxidant agents and also exhibited potential catalytic activity by converting 4 nitro-phenol to 4 amino phenols at rapid pace. It was concluded that the Tc-Ag NPs synthesized by ripe and unripe fruits almost showed similar results, and so both of them proved to have excellent multifunctional biomedical properties.