Characterization of haloalkalophilic organic solvent tolerant protease for chitin extraction from shrimp shell waste

- Paracoccus saliphilus APCMSTCS5 was isolated & identified from marine environment.
- This strain produced Halophilic Organic Solvent tolerant Protease (HOSP).
- Purified HOSP displayed better stain removal and antibiofilm activity.
- Biofermentation of shrimp shell waste by HOSP strain yielded chitin.
- Chitin purity was confirmed through FTIR and 13C CP/MAS NMR analysis.

Halophilic organic solvent tolerant protease (HOSP) producing Paracoccus saliphilus APCMST-CS5 was isolated from the marine sediment samples and identified through 16S rRNA sequence analysis. P. saliphilus APCMST-CS5 registered maximum HOSP production of 1,321.70 U/ml in the medium contained the most significant parameters such as shrimp shell powder (SSP), CaCl2, NaCl, and sardinella powder (SP), obtained through Placket-Burman and Response Surface Methods. HOSP was further purified to 22.68 fold purity with 29.71 U/mg specific activity and its molecular weight was 39 kDa. The HOSP was stable at 60 °C, 9.0 pH, 3.0 M NaCl concentration and it also showed maximum activity at other tested parameters. Interestingly the purified HOSP showed better antibiofilm ability against tested pathogens. Also, the HOSP effectively deproteinized (85.64%) shrimp shell chitin which in turn maximum and exhibited higher antioxidant activity. The commercial and experimental shrimp shell chitin showed similar peak pattern in FTIR and 13C CP/MAS NMR spectral analysis.