Characteristics of bivalve mollusk <i>Serripes groenlandicus </i>in connection with its rational use

Greenland cockle Serripes groenlandicus is a burrow bivalve mollusk that forms dense aggregations on silty-sandy and muddy grounds at the depth 50-60 m. Its total stock in Peter the Great Bay is estimated as 8,700 t. The species is not used yet as a raw material for food industry that is a reason to investigate its safety, chemical composition and technological characteristics. There is noted that the aggregations of S. groenlandicus in Peter the Great Bay are formed mostly by large-sized individuals (> 80 %), so they have high commercial value. Its soft tissue (on average 25.8 % of total weigh) contents 11.9 % of protein, < 1.0 % of fat, and 5.4 % of carbohydrate, its energy value is 70 kcal, so it is a promising raw material for low-calorie dietary products. Technological losses in mass of the clam meat in the process of broth extraction under hydrothermal treatment are rather high: 45-47 %. To prevent the mass losses, the species is recommended to use as the raw material for canned products with its natural meat

Antiradical effect of low-molecular peptides in extracts and hydrolyzates from tissues of water organisms

Molecular-weight composition of peptides in extracts and hydrolyzates from soft tissues of the clams Corbicula japonica and Mercenaria mercenaria and liver of chum salmon is investigated. Antiradical activity is defined for low-molecular peptides, as well as for high-molecular proteins and free amino acids in the extracts. The maximum activity is detected for the extracts of salmon liver; all protein fractions in the water extract of the liver have antiradical activity. Low-molecular peptides and free amino acids have antiradical activity in all samples. The peptides with molecular weight 4.3 kDa have the highest activity in the water extract from C. japonica (43 units) and the peptides with molecular weight 4.7 kDa - in the water extract from M. mercenaria (5.6 units). After hydrolysis, the portion of low-molecular peptides increases for C. japonica , M. mercenaria , and salmon liver in 22.1, 14.5, and 11.1 %, respectively. Hence antiradical activity for hydrolyzates from C. japonica and M. mercen aria is in 1.9 times higher and for hydrolyzates from salmon liver - in 1.3 times higher than for water extracts from their tissues. Only the peptides with molecular weight 2.8-4.7 kDa have antiradical activity in the hydrolyzates; its value is 1-24 activity units for M. mercenaria ; 13-76 units for C. japonica and about 40 units for the chum salmon liver. Correlation is found between the content of peptides with molecular weight 3-4 kDa in hydrolyzates and their antiradical activity

Antibiotics in aquaculture and their ecological significance. A review

Retrospective data concerning effects of antibiotics used in aquaculture on disease incidence for cultivated animals and humans are analyzed. Danger of the antibiotics use is shown for those used for both therapeutic and prophylactic purposes. The antibiotics could be consumed by humans with the production of aquaculture or exuded to environments in quantities able to cause microbial imbalance or contribute to development of resistant bacteria forms. These consequences lead to significant economic losses