Comparative analysis with biosynthesized nanoparticles by reducing and capping of identified Pterocarpus Santalinus bioactive compounds

Abstract

This research analyzed Pterocarpus santalinus leaf extract using LC-MS and identified 39 bioactive components, including isorhamnetin, kaempferol, quercetin, and trifolin. Silver and copper nanoparticles (PsAgNPs and PsCuONPs) were synthesized using reducing and capping of identified bioactive compounds and characterized using UV-Vis spectroscopy, XRD, FTIR, FESEM, TEM, Zeta potential, and DLS. PsAgNPs exhibited higher antibacterial activity against drug-resistant strains, with inhibition zones of 18 mm for Escherichia coli and 17 mm for Staphylococcus aureus at 100 µg/mL. In comparison, PsCuONPs showed inhibition zones of 16 and 14 mm at 175 µg/mL, respectively. PsAgNPs demonstrated antibacterial action at lower concentrations (MIC and MBC values at 50–75 µg/mL) compared to PsCuONPs (100 µg/mL). Both nanoparticles induced bacterial membrane perforation and cellular lysis, confirmed by FESEM. Additionally, PsAgNPs demonstrated superior anti-biofilm, antioxidant (DPPH: 6.97 µg/mL; ABTS: 3.92 µg/mL), and anti-inflammatory activities, inhibiting hemolysis (IC₅₀ = 4.17 µg/mL) and protein denaturation (IC₅₀ = 6.33 µg/mL) compared to PsCuONPs. Moreover, they displayed higher cytotoxicity against human breast cancer cell lines. This data suggests that PsAgNPs and PsCuONPs could be promising therapeutic molecules for antibacterial, anti-oxidative, anti-inflammatory, and anti-cancer applications.