JUMBO SQUID (Dosidicus gigas) SKIN PIGMENTS: CHEMICAL ANALYSIS AND EVALUATION OF ANTIMICROBIAL AND ANTIMUTAGENIC POTENTIAL

There is a great potential to use seafood by-products to create new beneficial products for customers. In a continued exploration of new chemical compounds from seafood by-products, jumbo squid (Dosidicus gigas) skin pigmented methanolic extracts (JSSE) were evaluated for their antimicrobial and antimutagenic activities. Pigments of JSSE were extracted with a yield of 635 mg/g and oxygen radical absorbance capacity-fluorescein (ORAC) with 178 qmol TE/g JSSE using optimal conditions: 25 °C and 5 min of sonication, established by factorial analysis. The antimicrobial activity of JSSE was evaluated using the agar diffusion method. The JSSE showed more than 50% inhibition against Haemophilys influenza, Listeria monocytogenes, Staphylococcus aureus, and Candida albicans. The high antimicrobial activity of JSSE (<90%) was detected in Salmonella enterica. The JSSE also inhibited mutation induced by aflatoxin B1 in the Salmonella tryphimurium strain TA98 (>50%), but not in the TA100 strain (<20%). Data on the solubility behaviour, the maximum absorbance (440 nm), protons observed in the ¹H NMR spectra, and the FT-IR spectra peak at 1742 cm^-1 of JSSE, suggest that the compound responsible for its antimicrobial and antimutagenic activities comes from the ommochrome family. The present study suggests that squid skin ommochromes are pigments of therapeutic value in near future applications in the food or health sector.