Abstract Significant opportunities exist in the use of seafood by-products to create new beneficial products. Moreover, cephalopod skin is a good source of bioactive compounds. The present study compares the chemical structure properties and antioxidant activity of pigments extracted from the skin of Octopus vulgaris (OVS) and Dosidicus gigas (DGS) with methanol-HCl (T1) and ethanol-HCl (T2). The solubility and spectroscopic analysis (UV-Vis and 1H NMR) indicated that extracted pigments belonged to the ommochrome family. Xanthommatin, dihydroxanthommatin, and kynurenine compounds were identified in the extracts using correlated homonuclear spectroscopy (COSY). The results showed that OVS yielded a higher recovery rate of pigments with antioxidant activity (DPPH, ABTS, and FRAP) than DGS in both solvents. T1 extracted the highest level of antioxidant pigments. The kynurenine proportion and proton peaks observed at 3.0-5.0 ppm (amino-aromatics) in the 1H NMR spectra may explain the differences in antioxidant activity of OVS and DGS.

Abstract In this work, an innovative strategy for raw chicken burger preservation, based on methanol–HCl extracts of octopus (Octopus vulgaris) (OVE) and squid (Dosidicus gigas) (DGE) skin pigments, was evaluated at 4 °C for 12 days. Burgers were prepared and divided into six groups: the control without any extract (CON), the control with 0.03% α-tocopherol (CET), and those containing 0.05% (OVE1, DGE1) and 0.1% (OVE2, DGE2) octopus and squid pigment extract, respectively. OVE yielded a higher rate of pigments with antioxidant activity (DPPH, ABTS, and ORAC) than DGE. The highest antimutagenic activity was detected in DGE according to the Ames’ Salmonella test. OVE1 and DGE1 burgers maintained lower pH values and were less sensitive to lipid oxidation (peroxide, anisidine, and total oxidation values). Evaluation of microbial growth by total bacterial count, lactic acid bacteria, Enterobacteriaceae spp., and fungi showed that OVE1 and DGE1 delayed bacterial contamination. The overall sensory quality was maintained for longer in the OVE- and DGE-supplemented chicken burgers than CON burgers. This study showed that OVE and DGE have potential as antioxidant and antimicrobial additives in chicken products.

Abstract Cancer represents the second leading cause of death worldwide, therefore, the search for chemoprotective agents is on the rise. The muscle of white shrimp (Litopenaeus vannamei) is one of the species analyzed as it has been reported as a source of compounds with antiproliferative activity. The aim of this study was to evaluate the effect of shrimp muscle-isolated compounds on cell proliferation and morphology of human cancer cell lines. The muscle underwent a process of extraction and fractionation of compounds; their effect on cell viability assays (MTT) on lung adenocarcinoma (A549), prostate carcinoma (22 Rv-1), invasive breast adenocarcinoma (MDA MB 231), colon carcinoma (HTC 116), cervix adenocarcinoma (HeLa) and non-cancerous retinal cells (ARPE-19) was measured. Morphological changes were observed using fluorescence microscopy and chemical structure data was obtained using nuclear magnetic resonance. Fraction named C5 showed the highest antiproliferative activity on HCT-116 and MDA-MB-231, without significantly affecting the control cells. Subfractions C5-3 and C5-4 presented significant antiproliferative potential in MDA-MB-231; this cell line showed morphological changes that could be related to apoptosis, and spectroscopic analysis revealed the presence of b-carotene and eicosapentaenoic acid in C5, nevertheless, further studies are needed to determine the effect of each compound.

Abstract Marine organisms have wonderful colors that make them very attractive. The unique characteristics of the compounds synthesized by species of marine origin go beyond their appearance. The pigments responsible for these colors are also capable of exerting biological activities, including the antioxidant capacity, which can be performed by different mechanisms. This has led to an increase in research attention due to their potential application in the pharmaceutical, cosmetics and food industries, and has expanded from in vitro studies to in vivo tests. The objective of this review is to compile and describe the studies aimed at establishing and elucidating the mechanisms of action of different biochemical compounds with antioxidant activities from marine species. In order to achieve that objective, the Scopus®, Web of Science™ and Microsoft Academic databases were used. Marine pigments represent a promising alternative to the antioxidants and synthetic additives used today. By establishing and understanding the mechanisms of action of the bioactive pigmented compounds isolated from marine organisms, it is possible to determine with greater precision their possible application in the industry.

Resumen Los organismos marinos poseen maravillosos colores que los hacen muy atractivos. Las características únicas de los compuestos sintetizados por especies de origen marino van más allá de su apariencia. Los pigmentos responsables de esos colores son capaces también de generar diversas actividades biológicas, como la capacidad antioxidante, la cual puede ocurrir a través de diversos mecanismos. Esto ha propiciado un aumento de su investigación, debido a su amplia aplicación en la biotecnología, farmacéutica, cosmética y alimentación de organismos vivos, expandiendo los estudios tanto in vitro como en ensayos in vivo. El objetivo de este trabajo fue compilar y describir diversos estudios recientes, enfocados en demostrar y elucidar los mecanismos de acción de los diferentes compuestos bioquímicos con actividad antioxidante, provenientes de algunos organismos marinos. Para ello, se utilizaron las bases de datos Scopus®, Web of Science™ y Microsoft Academic. Los pigmentos provenientes de organismos marinos representan una alternativa promisoria frente a los antioxidantes y aditivos sintéticos utilizados en la actualidad. El establecimiento y comprensión de los mecanismos de acción de los componentes pigmentados bioactivos, aislados de los organismos marinos, permitirá determinar con mayor precisión su posible aplicación en la industria.

AbstractHydrolysates from two different jumbo squid byproducts (fins and arms), produced by trypsin and protease type XIV were compared on the basis of their antioxidant (DPPH and ABTS radical scavenging assays), antimutagenic (Ames test) and antiproliferative (Transformation cell proliferation in M12.C3F6 murine cells) activities. Jumbo squid arms had higher content of collagen than fins, and their hydrolysates had the highest antioxidant activity. Also, jumbo squid arm-derived collagen hydrolyzed with protease XIV showed the highest antimutagenic activity. The four hydrolysates obtained showed low antiproliferative activity, however they are susceptible for further studies to be applied as food additives.

Fresh blue shrimp (Litopenaeus stylirostris) muscle was stored with antioxidants under different conditions: ANTIOX 2%, packed in bilayer film of polyamide-low density polyethylene film (PA-LDPE) with 2% α-tocopherol; ANTIOX 4%, packed in PA-LDPE film with 4% α-tocopherol; and ANTIOX-GLAZED, samples stored glazed with 2% α-tocopherol. Shrimps packed in PA-LDPE without α-tocopherol were used as CONTROL. All samples were stored at –20 °C for 120 days. As compared to the CONTROL, the shrimp stored with the antioxidant showed lower lipid oxidation (0.10-0.14 vs 1.58 mgMA/kg of muscle), lost less firmness and astaxanthin content. ANTIOX 2% and ANTIOX-GLAZED showed the lowest concentrations of formaldehyde (0.081-0.083 μM/g). There were no significant differences in color and sensory properties, but differences in the integrity of the muscle fibers were observed. The treatments with α-tocopherol maintained the shrimp muscle quality during frozen storage. However, no significant differences were found between these treatments.

Rancidity development during frozen storage (–20 °C) of sierra fish (Scomberomorus sierra) was studied. Fillets were packed in low-density polyethylene films with and without butylated hydroxytoluene added (BHT-LDPE and LDPE respectively). Fillets stored with no package were used as control. Special attention was given to the effect of previous ice storage (0, 3, 6, 9 and 15 days) on the quality of the frozen fish. Physical (pH and texture) and chemical (peroxide value, PV and thiobarbituric acid index, TBA-i) analyses were carried out. Lipid oxidation increased with ice storage time in fish muscle without film packing, being greater than the film packed muscle (with and without antioxidant). An effect of previous ice storage time was observed on the frozen product (in all treatments). However, fish muscle with film packing containing antioxidant showed less lipid deterioration. Under the conditions applied in this study, the plastic films with antioxidant prevented the lipids oxidation during the cold handling of the sierra muscle.

The marine bioprocessing industry offers great potential to utilize byproducts for fish meal replacement in aquafeeds. Jumbo squid is an important fishery commodity in Mexico, but only the mantle is marketed. Head, fins, guts and tentacles are discarded in spite of being protein-rich byproducts. This study evaluated the use of two jumbo squid byproduct hydrolysates obtained by acid-enzymatic hydrolysis (AEH) and by autohydrolysis (AH) as ingredients in practical diets for shrimp. The hydrolysates were included at levels of 2.5 and 5.0% of the diet dry weight in four practical diets, including a control diet without hydrolysate. Shrimp growth and survival were not significantly affected by the dietary treatments. Postharvest quality of abdominal muscle was evaluated in terms of proximate composition and sensory evaluation. Significantly higher crude protein was observed in the muscle of shrimp fed the highest hydrolysate levels, AH 5% (204.8 g kg- 1) or AEH 5% (201.3 g kg- 1). Sensory analysis of cooked muscle showed significant differences for all variables evaluated: color, odor, flavor, and firmness. It was concluded that Jumbo squid byproducts can be successfully processed by autohydrolysis or acid-enzymatic hydrolysis, and that up to 5.0% of the hydrolysates can be incorporated into shrimp diets without affecting growth or survival.

The effect of different feed processing methods on the physicochemical properties, and apparent digestibility of cowpea (Vigna unguiculata) meals as ingredients in diets for white shrimp (Litopenaeus vannamei) was investigated. Five experimental cowpea meals were prepared: whole raw (WRC), dehulled (DC), cooked (CC), germinated (GC) and extruded (EXC). The physicochemical properties of the meals were evaluated using differential scanning calorimetry. The meals were included at 15% in diets for L. vannamei (15.4 g) to determine firmness of pellets and in vivo digestibility of nutrients by using chromic oxide as inert marker. Six diets were evaluated: a control diet, and five diets containing the different cowpea meals. Transition enthalpy significantly decreased after thermal treatment, from 6.1 J/g in WRC to 1.4 J/g in CC, and disappeared in EXC. Firmness of pellets varied from 1.1 N in the EXC diet to 2.8 N in the WRC diet. A significant negative correlation between transition enthalpy and carbohydrate digestibility was found. Dry matter, protein, carbohydrate and lipid digestibility of cowpea meals significantly increased after germinating, cooking or extruding. It is concluded that germinated, cooked and extruded cowpea meals are highly digestible for shrimp and that enthalpy of transition is negatively correlated with the digestibility of carbohydrates.

Se evaluó el efecto de diferentes procesos sobre las propiedades fisicoquímicas y digestibilidad aparente de la harina de frijol yorimón (Vigna unguiculata) como ingrediente en alimentos para camarón blanco (Litopenaeus vannamei). Se elaboraron cinco harinas de frijol yorimón: entero crudo (WRC), decorticado (DC), cocido (CC), germinado (GC) y extruido (EXC). Las características térmicas de las harinas fueron evaluadas usando calorimetría diferencial de barrido. Se elaboraron seis alimentos experimentales: un alimento control y cinco alimentos conteniendo 15% de las diferentes harinas de frijol yorimón. A estos alimentos se le determinó firmeza y digestibilidad in vivo de nutrientes para L. vannamei (15.4 g) usando óxido de cromo como marcador inerte. La entalpía de transición decreció después del tratamiento térmico, de 6.1 J/g en la WRC a 1.4 J/g en la CC, y desapareció en la EXC. La firmeza de los alimentos varió de 1.1 N en el alimento con EXC a 2.8 N en el alimento con WRC. Se encontró una correlación significativa negativa entre la entalpía de transición y la digestibilidad de carbohidratos de la harina del frijol yorimón. La digestibilidad de materia seca, proteína, carbohidratos y lípidos de las harinas de frijol yorimón aumentó significativamente con el germinado, la cocción y la extrusión. En el presente estudio se concluye que las harinas de frijol yorimón germinado, cocido y extruido son altamente digeribles para camarón L. vannamei, y la entalpía de transición se correlaciona significativamente con la digestibilidad de los carbohidratos.