Preparation and use of media for protease-producing bacterial strains based on by-products from Cuttlefish (Sepia officinalis) and wastewaters from marine-products processing factories

SummaryCuttlefish powder (CFP) from Sepia officinalis by-products was prepared and tested as a fermentation substrate for microbial growth and protease production by several species of bacteria: Bacillus licheniformis, Bacillus subtilis, Pseudomonas aeruginosa, Bacillus cereus BG1, and Vibrio parahaemolyticus. All microorganisms studied grew well and produced protease activity when cultivated in medium containing only CFP indicating that the strains can obtain their carbon and nitrogen source requirements directly from whole by-product proteins. Moreover, it was found that the addition to the cuttlefish medium of diluted fishery wastewaters (FWW), generated by marine-products processing factories, enhanced the production of protease. Maximum activity was obtained when cells were grown in cuttlefish media containing 5-times or 10-times diluted FWW. Five-times diluted FWW enhanced protease production by B. cereus BG1 and B. subtilis by 467% and 75% more than control media, respectively. The enhancement could have been due to the high organic content or high salts in FWW.As a result, cuttlefish by-products powder enriched with diluted FWW was found to be a suitable growth media for protease-producing strains. This new process, which converts underutilized wastes (liquid and solid) into more marketable and acceptable forms, coupled with protease production, can be an alternative way to the biological treatment of solid and liquid wastes generated by the cuttlefish processing industry.