Trends in valorization of the invasive crab Portunus segnis for cleaner production of chitin, chitosan, and protein hydrolysate

Abstract

The diversity of marine biomasses is a set of exploitable and renewable resources with application in several sectors. In this context, a co-culture based on three protease-producing bacterial isolates namely; Aeribacillus pallidus VP3, Lysinibacillus fusiformis C250R , and Anoxybacillus kamchatkensis M1V strains, was carried out in a medium based on the invasive blue crab Portunus segnis bio-waste. Optimization of proteases production was performed using a central composite design (CCD). The highest level of proteases production obtained was 8,809 U/mL in a medium comprising 75 g/L of Portunus segnis by-product powder (Pspp ). The recovered protein hydrolysate (P Hyd ) was found to be active towards radical scavenging power, and against angiotensin I-converting enzyme (ACE). The extraction efficiency of the blue crab chitin (BC) was achieved with a yield of 32%. Afterward, chitosan was prepared through chitin N -deacetylation with a yield of 52%, leading to an acetylation degree (AD) of 19% and solubility of 90%. The spectrum of chitin and chitosan were depicted by Fourier-transform infrared spectroscopy (FTIR). The biological value of Pspp and its obtained derivates were evidenced via accredited protocols. These data constitute a roadmap towards a circular and sustainable bio-economic strategy for a clean transformation of a recalcitrant waste to bio-based products.

Development of the fishing and commercialization of the blue crabs in Bizerta and Ghar EL Melh lagoons: A case study of promotion opportunities of blue growth in Tunisia

“…Biochemical analyses, as made by bejaoui et al 14 of the blue crab meat will be conducted in order to prepare a file for the zoosanitary classification in relation to these species. This classification is essential for the sustainability of the activity of exploitation and marketing of this resource.…”

“…In Tunisia, non-native crabs represent 70.58% of total alien decapoda. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] The Lessepsian P. Segnis (Figure 1 B) is one of the first non-indigenous species (NIS) and is an active carnivorous predator 19,15 with large populations recorded in the Gulf of Gabes (Southern Tunisia). 4 Few months after its first entrance, the blue crab bloomed and became a threat to artisanal fishermen with serious socio-economic impacts.…”