Antioxidant defense of fish collagen peptides attenuates oxidative stress in gastric mucosa of experimentally ulcer-induced rats.

The aim of the present study was to investigate the ability of fish collagen peptides (FCP) from the skin of great hammerhead shark (Sphyrna mokarran) to avert the occurrence of gastric ulcer in experimental rats. FCP treatment prevented the formation of ulcerative lesions on gastric tissues with 86% of inhibition. The histopathology analysis of gastric tissue revealed that the FCP intake prevented the occurrence of hemorrhage and erosion in gastric tissue with formation of mild edema and necrosis, as well as normalized the pH and volume of gastric juice. It also downregulated the expression of pro-inflammatory marker interferon-ɤ (IFN-ɤ) and upregulated the anti-inflammatory marker interleukin-4 (IL-4) in gastric tissue. FCP is capable to modulate the oxidative stress by enhancing the activity of antioxidant defense enzymes superoxide dismutase (SOD) and catalase and by lowering the levels of membrane lipid peroxidation.

Microbiological and biochemical changes in pearl spot (Etroplus suratensis Bloch) stored under modified atmospheres.

AIMS: This study aimed to determine the effect of packaging [air, modified atmosphere (MA)] on microbial growth, sensory and chemical parameters and also on shelf life of fresh pearl spot (Etroplus suratensis Bloch) and on the selection of microbial association. METHODS AND RESULTS: Fresh pearl spot (whole, gutted) were packaged under both 100% air and MAs (40%CO(2)/60% O(2), 50%CO(2)/50%O(2), 60% CO(2)/40%O(2), 70% CO(2)/30% O(2) and 40% CO(2)/30% O(2)/30% N(2)) and stored at 0 degrees C. Microbial growth (counts of total aerobic bacteria, H(2)S-producing bacteria, Lactic acid bacteria, Brochothrix thermosphacta, yeast and mould), chemical spoilage indicators (pH, total volatile basic nitrogen) and sensory characteristics were monitored. Microbial changes in Pearl spot packed under 100% air and 40% CO(2)/30%O(2)/30% N(2) were similar. The total volatile basic nitrogen values increased, but the values never exceeded the acceptability limit of 25 mg 100 g(-1). CONCLUSIONS: MA 60% CO(2) : 40%O(2) was found to be better with a shelf life of 21 days whereas air stored samples had a shelf-life of 12-14 days only. SIGNIFICANCE AND IMPACT OF THE STUDY: Storage of pearl spot under MAs 60% CO(2) : 40%O(2) is a promising method to extend shelf-life. Longer shelf life expands the market potential of pearl spot and reduces waste during distribution and retail display.