Synthesis of Inonotus rickii metabolite-loaded chitosan nanoparticles and its biological activities

Inonotus rickii, a mushroom fungus classified as a Hyamenochetae, is commonly observed in the Western Ghats region of Maharashtra, India. The metabolites extracted from this mushroom exhibit various biological activities. On the other side, currently chitosan nanoparticles emerging as an effective nanocarrier for targeted treatments. Therefore in the present study nanoparticles from biopolymer chitosan loaded with I. rickii metabolites of different solvent extract were synthesized and their antioxidant, antibacterial and anticancer potential were evaluated. The synthesized NPs were spherical in shape, and the average size for pure chitosan nanoparticles (CHI-NPs) was 58.02 nm, I. rickii aqueous CHI-NPs (U2-Aq-CHI-NPs) 62.70 nm, I. rickii acetone CHI-NPs (U2-Ac-CHI-NPs) 17.11 nm, and I. rickii ethanol CHI-NPs (U2-Et-CHI-NPs) 27.05 nm. These I. rickii metabolite-loaded CHI-NPs exhibited antibacterial, antioxidant, and cytotoxic activities. The U2-Ac-CHI-NPs showed significant antibacterial actions against four bacterial strains such as E. coli, Bacillus cereus, Pseudomonas otitidis, and Chryseobacterium spp. It also showed significantly higher antioxidant activity (95.8±1.6 %). Moreover, a significant decrease in the cell viability of the HeLa cell line was noticed with a subsequent increase (1–1000 µg/mL) in the concentration of metabolite-loaded CHI-NPs. A U2-Aq-CHI-NPs lower concentration is also significant to decrease cell viability. The LC-MS analysis revealed the presence of different bioactive compounds like Hispolon, Inoscavins, Methyl inoscavins, and Phelligridins in all tested extracts of I. rickii supports the bioactivities. Therefore, the synergistic effect of I. rickii-derived metabolite-loaded CHI-NPs suggested a significant perspective for the targeted drug delivery-based treatment with diminished side effects.