Unlocking antimicrobial potentials of Sepiella inermis cuttlebone derived phosphorylated chitosan

Chitosan, a biopolymer made from chitin, has drawn attention from researchers because of its antimicrobial, biocompatible, and biodegradable properties. Sepiella inermis cuttlebone serves as the natural source of chitin, which can undergo phosphorylation to enhance its antimicrobial properties. When using phosphorylated chitosan, it appears that several infections, which are the underlying causes of a wide range of illnesses, can be treated. The aim of this study is to investigate the synthesis and characterization of phosphorylated chitosan derived from cuttlebone and evaluate the effects of varying doses on the inhibition of clinical pathogens that cause infections ( Streptococcus mutans , Pseudomonas aeruginosa , E. coli, and Candida tropicalis ). The cuttlebone of a specimen of Sepiella inermis was utilized to extract the chitin and chitosan. The next step involved phosphorylating the chitosan to produce phosphorylated chitosan. Then, we evaluated the antibacterial properties of phosphorylated chitosan using the well diffusion method. After that, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and Fourier transform infrared spectroscopy (FTIR) were used to analyze and assess it. The study's results suggest that Sepiella inermis cuttle bones could serve as a unique natural anti-microbial source for therapeutic applications. The well-diffusion method, which measures antimicrobial activity, demonstrated the effectiveness of phosphorylated chitosan as an antimicrobial agent. Phosphorylated chitosan inhibited Candida tropicalis at 100 % concentration and Pseudomonas aeruginosa at 50 % and 100 % concentrations. The inhibitory effects on Streptococcus mutans and E. coli were weak. The main aim of this work is to produce phosphorylated chitosan and subsequently demonstrate its antibacterial and antifungal action against clinical infections. We also found that the concentration of phosphorylated chitosan significantly influences its microbial growth, with higher concentrations demonstrating more potent inhibitory effects. Based on these findings, phosphorylated chitosan has the potential to be a component in pharmaceutical products that target clinical microorganisms. • Phosphorylated chitosan from Sepiella inermis cuttlebone showed strong antimicrobial effects. • XRD, FESEM, and FTIR confirmed successful synthesis and characterization. • Well-diffusion method demonstrated potent inhibition of clinical pathogens. • Higher concentrations of phosphorylated chitosan showed enhanced antimicrobial activity.