Oligochitosan recovered from shrimp shells through subcritical water hydrolysis: Molecular size reduction and biological activities

Oligochitosan (OC) from shrimp shells derived chitosan was prepared using subcritical water hydrolysis (SWH) and their physicochemical and bio-functional properties were observed in this study. Reaction time of SWH was varied from 15 min to 60 min and the temperature from 140 °C to 170 °C. Gel permeation chromatography (GPC) confirmed that the molecular weight of the chitosan hydrolysate (CH) at 170 °C/15 min was obtained at 3.06 kDa. Fourier transform infrared and X-ray diffraction spectroscopy confirmed the conversion of OC from CH. Bio-functionality of CH was tested on the basis of antioxidant, antimicrobial, and anticancer activities. The ability of OC to act against the pancreatic cancer cell line Panc 1 was analyzed by MTT assay and Syto 9/PI fluorescent techniques. The MTT assay indicated that the maximum cytotoxicity was revealed by OC (170 °C/15 min) at 500 µg/mL. This research revealed that SWH can be an efficient method for the production of OC.