Decoding Octopus Skin Mucus: Impact of Aquarium-Maintenance and Senescence on the Proteome Profile of the Common Octopus (Octopus vulgaris).

The common octopus (Octopus vulgaris) is an excellent candidate for aquaculture diversification, due to its biological traits and high market demand. To ensure a high-quality product while maintaining welfare in captive environments, it is crucial to develop non-invasive methods for testing health biomarkers. Proteins found in skin mucus offer a non-invasive approach to monitoring octopus welfare. This study compares the protein profiles in the skin mucus of wild, aquarium-maintained, and senescent specimens to identify welfare biomarkers. A tandem mass tag (TMT) coupled with an Orbitrap Eclipse Tribrid mass spectrometer was used to create a reference dataset from octopus skin mucus, identifying 1496 non-redundant protein groups. Although similar profiles were observed, differences in relative abundances led to the identification of potential biomarkers, including caspase-3-like, protocadherin 4, deleted in malignant brain tumors, thioredoxin, papilin, annexin, cofilin and mucin-4 proteins. Some of these proteins also revealed potential as bioactive peptides. This investigation provides the most extensive analysis of the skin mucus proteome in the common octopus and is the first to explore how aquarium maintenance and senescence alter the mucus proteome. This research highlights the potential of skin mucus protein/peptides as non-invasive monitoring biomarkers in cultured animals.

The Effect of Salvia hispanica and Nigella sativa Seed on the Volatile Profile and Sensory Parameters Related to Volatile Compounds of Dry Fermented Sausage.

The aim of the study was to evaluate the effects of Salvia hispanica and Nigella sativa seed addition on the volatile compounds and sensory characteristics (with particular emphasis on odor and flavor) of traditionally produced dry fermented sausages with reduced nitrites. Five different sausage formulations were prepared: control sample; samples with 1% and 2% addition of chia seed; samples with 1% and 2% addition of black cumin seed. The sausages were subjected to analysis including proximate chemical composition, volatile compound determination, and sensory analysis. The sausages with chia seed in the amounts of 1% and 2% as well as the sample with 1% addition of black cumin seed were characterized by positive sensory features, and their overall quality was rated above 7 c.u. on a 10-point scale, similar to the control sausage. Sausage samples with the addition of cumin seed were characterized by the highest herbal odor and flavor. The addition of Salvia hispanica and Nigella sativa seed significantly affected the amount of volatile compounds in fermented sausages. Sausages with black cumin presented the greatest amount of total volatile compounds, mainly contributed by terpenes.

In Search of Antioxidant Peptides from Porcine Liver Hydrolysates Using Analytical and Peptidomic Approach.

The search for antioxidant peptides as health-promoting agents is of great scientific interest for their biotechnological applications. Thus, the main goal of this study was to identify antioxidant peptides from pork liver using alcalase, bromelain, flavourzyme, and papain enzymes. All liver hydrolysates proved to be of adequate quality regarding the ratio EAA/NEAA, particularly flavourzyme hydrolysates. The peptidomic profiles were significantly different for each enzyme and their characterizations were performed, resulting in forty-four differentially abundant peptides among the four treatments. Porcine liver hydrolysates from alcalase and bromelain are demonstrated to have the most antioxidant capacity. On the other hand, hydrophobic amino acid residues (serine, threonine, histidine and aspartic acid) might be reducing the hydrolysates antioxidant capacity. Seventeen peptides from collagen, albumin, globin domain-containing protein, cytochrome ß, fructose-bisphosphate aldolase, dihydropyrimidinase, argininosuccinate synthase, and ATP synthase seem to be antioxidant. Further studies are necessary to isolate these peptides and test them in in vivo experiments.

Peptidomic analysis of antioxidant peptides from porcine liver hydrolysates using SWATH-MS.

There is a growing interest in the production and identification of bioactive peptides as health-promoting agents. A relevant method to produce biopeptides is enzymatic hydrolysis from protein-rich meat by-products. Pork liver proved to be a good source of protein (18.54%) with a low-fat content (3.38%). After hydrolysis at different times (4,6,8 and 10 h) with Alcalase, relevant amino acids such as hydrophobic (leucine, valine and isoleucine) and aromatic (tyrosine and phenylalanine) involved in antioxidant capacity were strongly increased. For the peptidomic analysis, a novel technique called sequential window acquisition of all theoretical mass spectra (SWATH-MS) was used. Regarding the effect of hydrolysis time, PCA demonstrated a great differentiation among the peptidomic pattern. Fifty-one peptides were correlated with antioxidant activity measured by DPPH, ABTS, FRAP and ORAC assays. SWATH-MS allowed the identification and quantification of six peptides from trypsinogen, ferritin, keratin, carboxylic ester hydrolase and globin domain-containing protein as potential antioxidant compounds. SIGNIFICANCE: The pork liver tissue contains a substantial amount of proteins whose enzymatic hydrolysis might generate antioxidant peptides. The bioactive peptides from pork liver would contribute to harnessing by-products of the swine industry as well as added-value products will be produced. The antioxidant activity of the mixtures revealed potential antioxidant peptides which could be used in the development of nutraceutical and functional food products.

Antioxidant activity and peptidomic analysis of porcine liver hydrolysates using alcalase, bromelain, flavourzyme and papain enzymes.

Antioxidant peptides are increasingly being recognized as food additives due to their effects on body human, regulating in vivo oxidative stress against oxidation of lipids and proteins. Meat by-products are rich sources of protein that can be employed for this purpose. Specifically, porcine liver can be used to prepare hydrolysates with antioxidant activity employing proteolytic enzymes such as alcalase, bromelain, papain and flavourzyme. In this study, the antioxidant activity of these four porcine liver hydrolysates was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ((2,2-azinobis-(3-ethyl-benzothiazoline-6-sulphonate) (ABTS), Ferric reducing antioxidant power assay (FRAP) and Oxygen radical absorbance capacity assay (ORAC) assays and the identification of bioactive peptides was carried out by SWATH-MS technology. According to the SDS-PAGE pattern, the proteolysis index and the free amino acids amount, the protein degradation was clearly different among the studied enzymes. Indeed, alcalase enzyme produced the release of small peptides, meanwhile flavourzyme produced higher level of free amino acids. The heatmap analysis showed a peptidomic pattern more differentiated for alcalase than for the other enzymes. The peptides most abundant and correlated with antioxidant capacity were APAAIGPYSQAVLVDR from uncharacterized protein, GLNQALVDLHALGSAR, ALFQDVQKPSQDEWGK and LSGPQAGLGEYLFER from ferritin and LGEHNIDVLEGNEQFINAAK from trypsinogen. The production and characterization of biopeptides is a new merging challenge of meat industry.