A step to shell biorefinery-Extraction of astaxanthin-rich oil, protein, chitin, and chitosan from shrimp processing waste

Management of waste generated in fish processing industries is of great concern worldwide. Shrimp processing waste can be used for the generation of various biobased products along with its remediation. The present work was carried out to valorize shrimp processing waste using biorefinery approach. Ridgeback shrimp (Solenocera choprai) waste was used to produce commercially important biomolecules such as astaxanthin-rich oil, protein, chitin, and chitosan. Supercritical carbon dioxide extraction was performed for the extraction of astaxanthin and oil. Astaxanthin yield using super critical fluid extraction method was 30.26 +/- 0.06 mg/kg dry shell weight. Extracted oil was found to have high content of health promoting polyunsaturated fatty acids, in particular omega-3 fatty acids, viz, eicosapentaenoic acid and docosahexaenoic acid. The remaining waste after the supercritical fluid extraction was used for protein extraction and the recovery yield was found to be 22.25 +/- 0.15%. The residue left after extraction of astaxanthin and protein was used to extract chitin and the extracted chitin was used to produce chitosan. The yield of chitin and chitosan was 224.36 +/- 0.32 g/kg and 156.99 +/- 0.16 g/kg, respectively. The significant findings of the study suggest the potential of biorefinery in utilizing shrimp processing waste to produce commercially important products.