Sustainable and Integral Valorization of Dosidicus gigas Pen Waste: Combined Production of Chitosan with Antibacterial Properties and Human and Marine Probiotics

Year: 2025

Type: article

Abstract: This study details a biorefinery approach to valorize Dosidicus gigas squid pen waste. The process starts with the enzymatic deproteinization of squid pens, which prove effective with both Alcalase and Novozym, with the latter exhibiting a slightly higher efficiency to yield a material with 73% chitin content. Subsequent alkaline hydrolysis produces highly deacetylated chitosan (>90% degree of deacetylation), followed by controlled depolymerization to obtain polymers with molecular weights ranging from 50 to 251 kDa. Both native and depolymerized chitosan exhibit antimicrobial activity against Escherichia coli and Bacillus cereus, with B. cereus demonstrating greater resistance to chitosan compared to E. coli. The research also explores the bioconversion of deproteinization and deacetylation effluents. Deproteinization effluents prove superior in sustaining microbial growth, supporting comparable growth and lactic acid production for human probiotic strains (Lactobacillus plantarum and Leuconostoc mesenteroides) when substituting commercial peptones. Marine bacteria (Pseudomonas fluorescens and Phaeobacter sp.) show lower productivity. Integrating these processes into a biorefinery framework enables the conversion of 1 kg of dry squid pens into 350 g of chitosan, and facilitates the production of 937–949 g of lactic acid using human lactic acid bacteria cultures in media formulated with squid pen-derived effluents, glucose, yeast extract, and mineral salts. This integrated approach highlights the potential for maximizing resource utilization from squid pen waste, reducing environmental impact and generating high-value bioproducts.

Source: Marine Drugs

DOI: 10.3390/md23100382

Authors: Marta Lima, Adrián Pedreira, Noelia Sanz, José Antonio Vázquez, Míriam R. García, Filipe Mergulhão, Jesus Valcarcel

Institutions: Universidade do Porto, Consejo Superior de Investigaciones Científicas, Instituto de Investigacións Mariñas

Language: English

Topic: Nanocomposite Films for Food Packaging

Subfield: Biomaterials

Field: Materials Science

Domain: Physical Sciences

SDG: Responsible consumption and production

Open Access status: gold

Estimated APC paid: $3,499

Funders: Ministerio de Ciencia, Innovación y Universidades, European Commission, Ministério da Ciência, Tecnologia e Ensino Superior, Universidade de Vigo, Xunta de Galicia, Fundação para a Ciência e a Tecnologia, European Regional Development Fund, Agencia Estatal de Investigación, Interreg

OpenAlex ID: W4414610281