Zhao-hong Shi

Bio: Zhao-hong Shi is an academic researcher from Chinese Academy of Fishery Sciences. The author has contributed to research in topics: Polyunsaturated fatty acid & Docosahexaenoic acid. The author has an hindex of 1, co-authored 1 publications receiving 67 citations.

Chemical composition and nutritional quality of sea cucumbers

Abstract: BACKGROUND: The dried form of sea cucumbers has been a seafood and medicinal cure for Asians over many centuries. In this study the chemical composition and nutritional quality of eight common sea cucumbers (Stichopus herrmanni, Thelenota ananas, Thelenota anax, Holothuria fuscogilva, Holothuria fuscopunctata, Actinopyga mauritiana, Actinopyga caerulea and Bohadschia argus) were determined. RESULTS: All species except T. anax and A. caerulea had higher protein and lower fat levels. A. mauritiana and B. argus had less ash content. Glycine was the dominant amino acid found in all species, and content ranged from 126 to 216 mg g(-1) of crude protein. All species exhibited low lysine : arginine ratio and higher essential amino acid scores were obtained by threonine and phenylalanine + tyrosine. A. mauritiana had proportionally less saturated fatty acids (31.23%), and more monounsaturated fatty acids (45.64%) and polyunsaturated fatty acids (PUFA, 23.13%) than other species. Arachidonic acid (C20 : 4n-6) was the major PUFA in all species. T. ananas, A. mauritiana and A. caerulea contained more n-3 PUFA. The n-3/n-6 ratios of eight sea cucumbers species ranged from 0.25 to 0.61. CONCLUSION: Sea cucumbers are a seafood with high protein and low fat levels. The amino acid contents were similar but fatty acid profiles were different among species. The comparison showed that T. ananas, A. mauritiana and B. argus possessed higher nutritional values than other sea cucumber species. (c) 2010 Society of Chemical Industry

Amino Acid and Fatty Acid Composition of the Muscle Tissue of Yellowfin Tuna (Thunnus Albacares) and Bigeye Tuna (Thunnus Obesus)

Abstract: The nutritional compositions of yellowfin tuna (Thunnus albacares) and bigeye tuna (Thunnus obesus) were investigated. The two species had high protein (23.52 – 23.72%) and low fat content (1.93 – 2.06%). No significant differences were found in the moisture, protein, fat, and ash contents between the two tuna fish species. Eighteen amino acids were identified in both fish species, and glutamic acid was the most predominant (12.45% in yellowfin tuna and 11.28% in bigeye tuna). The total amino acid (TAA) content ranged between 82.66% and 84.49% (dry weight). The ratios of essential amino acids (EAA) to TAA in yellowfin tuna and bigeye tuna were 44.95% and 45.64%, respectively. With the exception of tryptophan, the other EAA scores were >100 %. The major fatty acids were C16:0, C18:1, C22:6 (DHA), and C18:0. Yellowfin tuna had a higher concentration of DHA (20.22%, % of total fatty acids), however, no significant differences in C20:4 (ARA) and C20:5 (EPA) were found between the two tuna fish. The n-3/n-6 ratios of yellowfin tuna and bigeye tuna were 3.29 and 4.56, respectively. This study shows that these tuna species have high nutritional qualities.

Chemical composition of the giant red sea cucumber, Parastichopus californicus, commercially harvested in Alaska.

Abstract: Giant red sea cucumbers, Parastichopus californicus, are commercially harvested in the U.S. Pacific Northwest; however, the nutritional and chemical properties of its edible muscle bands and body wall have not been fully elucidated. In particular are the fatty acid profiles of P. californicus tissues, which have not been documented. Sea cucumbers were delivered live and muscle bands and body wall freeze dried, vacuum packed, and stored at -30°C until analyzed. Proximate composition of freeze-dried tissues varied greatly with muscle bands being composed of 68% protein, 12% ash, 9% carbohydrate, and 5% lipids, while the body wall was composed of 47% protein, 26% ash, 15% carbohydrate, and 8% lipids. The hydroxyproline, proline, and glycine contents of the body wall were much higher than those in muscle bands, consistent with the larger amount of connective tissue. Calcium, magnesium, sodium, and iron contents were higher in the body wall than those in muscle bands, whereas the opposite was observed for zinc content. Total long-chain n-3 fatty acid contents were 19% and 32% of total fatty acids in body wall and muscle bands, respectively. Muscle bands had higher content of eicosapentaenoic acid (20:5n-3) than body wall at 22.6% and 12.3%, respectively. High content of arachidonic acid (20:4n-6) was recorded in both body wall (7.1%) and muscle bands (9.9%). Overall, the fatty acid profiles of body wall and muscle bands of P. californicus resemble those described for other species; however, the distribution and occurrence of certain fatty acids is unique to P. californicus, being representative of the fatty acid composition of temperate-polar marine organisms. The chemical characterization of freeze-dried edible tissues from P. californicus demonstrated that these products have valuable nutritional properties. The body wall, a food product of lower market value than muscle bands, could be better utilized for nutraceutical and pharmaceutical applications.

Nutritional Quality in Terms of Amino Acid and Fatty Acid of Five Coldwater Fish Species: Implications to Human Health

Abstract: Muscle samples of Tor putitora, Neolissochilus hexagonolepis, Oncorhynchus mykiss, Schizothorax richardsonii and Cyprinus carpio were analyzed for fatty acid and amino acid composition with a view to generate nutritional information of the five important coldwater fish species of Indian upland Himalayan region. In the present study, all the fish species recorded good amounts of n-3 fatty acids (8.69–21.48 %) and the n-3/n-6 ratio ranged from 0.7 to 4.98. The amino acid score calculated based on the World Health Organization (WHO) protein standard indicated good quality proteins in the species but with mostly marginally lower values for C. carpio. However, when the amino acid levels of the fish species were compared with the recommended amino acid levels, all the fish species were found to constitute a good source of essential amino acids. Limiting amino acids such as lysine, methionine and cysteine occurred at levels higher than or marginally lower than the recommended amino acid profile. It could be concluded that the five coldwater fish species from upland Himalayan region contained high quality lipids and proteins constituting a healthy addition to the human diet.