Sung-Ju Rha

Variation in the Chemical Composition of Saccharina Japonica with Harvest Area and Culture Period

Saccharina japonica is commercially important marine brown algae which grow as a single blade (reaching 10 meters in length) with a short stipe. In this study, the edible brown weed Sacchaina japonica was assessed for nutritional composition. Samples were collected monthly from seaweed farms at Kijang and Wando on the south coast of the Republic of Korea, during the 2011 culture season. S. japonica in Kijang and Wando showed the highest crude protein content in February and the highest carbohydrate content in July. Monthly changes in sugar, fatty acid, mineral, and total amino acid contents observed from February to July 2011. Fucose was the most abundant and galactose the second most abundant in the monosaccharide composition profiles, while mannose, glucose, xylose, ribose, and rhamnose were present in low quantities and lactose, mannitol, and arabinose were not detected. Significant increases of the major fatty acids in Kijang (C18:2 n-6 and C20:4 n-6) and Wando (C18:3 n-6) were observed as the culture period progressed. The highest mineral content of both Kijang and Wando samples is potassium and followed by sodium, calcium, magnesium, and so on. In the total amino acid contents, Kijang samples increased from February to April but decreased from May to July, while Wando samples increased on March but decreased from April to July.

Biochemical characteristics of four marine fish skins in Korea

In this study, we investigated the biochemical characteristics of the fish skins of four industrial species: olive flounder (Paralichthys olivaceus), black rockfish (Sebastes schlegeli), sea bass (Lateolabrax maculatus) and red sea bream (Pagrus major). There is high domestic demand in Korea for farming of these fish for human consumption. Crude protein contents in the skin of these fish ranged from 73% to 94% by dry weight; this was in part due to a high content of the structural protein, collagen. Among the four species, olive flounder had the thickest dermal and epidermal layers in the dorsal skin. This species was also associated with the highest extraction ratio of acid-soluble collagen. We also examined whether fish skin could be a cost-effective alternative to current fish meal sources. Our analysis indicates that, when supplemented with additional fish oils and essential amino acids, fish skin is a viable alternative for fish meal formulations.

Characterization of angiogenesis inhibitor effect of green tea seed extract

Abstract Green tea seed was extracted with absolute ethanol, and the green tea seed extract (GTSE) was subjected to assays for toxicity, antioxidant ability, angiogenesis inhibitory effects and cell adhesion, as well as western blotting, and an in vivo experiment against 4 high‐ranking adult cancers in Korea. Our series of experimental data demonstrated that GTSE has an antioxidant ability superior to that of EGCG in the green tea leaf, and also exhibits a profound high tumor growth inhibitory activity on a variety of cancer cell lines, as well as nude mice infected with cancer cells. GTSE was identified as a natural anticancer compound showing excellent angiogenesis inhibition and cancer cell suppression abilities. Our preliminary observations also indicate that GTSE may be another potential source of natural dietary antioxidants and also may be applicable as a novel natural anticancer agent.

Body Composition of Black Rockfish Sebastes schlegeli Fed on Diets Containing Different Levels of Turmeric Curcuma longa L.

This study investigated the effect of diets supplemented with different levels (0, 1, 3, and 5 %) of turmeric Curcuma longa L. powder (TP) on the body composition of black rockfish Sebastes schlegeli. Fish weighing g were fed to apparent satiation twice daily for 8 weeks. Adding TP decreased crude lipid levels and increased crude protein and ash levels. Abundant fatty acids in the TP-added group were C16:0, C18:1 n-9 (cis), and C22:6 n-3. The major amino acids in samples were glutamic acid, aspartic acid, glycine, leucine, alanine, lysine, and arginine.

Nutritional Characteristics of Juvenile Black Rockfish Sebastes schlegeli Fed a Diet of Fig Leaf Extract

The present study investigated the effect of diets supplemented with different levels (0, 1, 3, and 5 %) of fig leaf ethanol extract (FLEE) on the nutritional composition of black rockfish Sebastes schlegeli. Fish () were fed to apparent satiation twice daily for 8 weeks. Adding FLEE decreased crude lipid levels and increased crude protein and ash. Among the three organic acids in the whole body of black rockfish, lactic acid was predominant, followed by citric acid and oxalic acid. Five free sugars were found in all groups. Fucose and glucose were the dominant free sugars in the FLEE-added group. The abundant fatty acids in the FLEE-added group were C16:0, C18:1-cis (n9), and C22:6n-3. The major amino acids in the samples were glutamic acid, aspartic acid, glycine, leucine, alanine, lysine, and arginine. The abundant free amino acids in the FLEE-added group were taurine, glutamic acid, alanine, leucine, and arginine.

Nutritional Composition Changes in Skate (Raja kenojei) during Different Ripening Periods

In order to suggest fundamental data on the nutritional composition of the Korean traditional food, ripened skate, this study investigated the proximate composition, organic acid, free sugar, fatty acid, total amino acid, and macromolecule levels of skates at different ripening periods. Longer ripening periods resulted in decreased moisture levels and increased protein and ash levels. The total organic acid content increased until the 15th day of ripening, but decreased at 20 days. Phosphoric acid, oxalic acid, and lactic acid were the dominant organic acids. Eight free sugars were detected, ribose, glucose, and sucrose being the dominant forms, which significantly decreased with ripening. Palmitic and lignoceric acid were abundant in saturated fatty acids, oleic acid and palmitoleic acid were abundant in monounsaturated fatty acids, and linolenic acid, docosahexenoic acid, and arachidonic acid were abundant in polyunsaturated fatty acids. The major amino acids were glutamic acid, lysine, aspartic acid, and leucine and the total levels increased with ripening. The most abundant free amino acids were urea, sarcosine, taurine, and β-alanine, which decreased with ripening. Phosphoserine, phosphoethanolamine, α-aminobutyric acid, and cysteine levels increased.

Nutritional characteristics of black rockfish (Sebastes schlegeli) fed a diet of fish skin.

This study investigated the effects of diets substituted with different levels (0, 5, 10, and 20%) of flounder skin meal (FSM) on the nutritional composition of black rockfish Sebastes schlegeli. Fish (10.05 ± 0.44 g) were fed to apparent satiation twice daily for 8 weeks. Adding FSM decreased crude lipid levels and increased crude protein and ash. The abundant fatty acids in the FSM-added group were C16:0, C18:1-cis (n9), and C22:6n-3. The major amino acids in the samples were glutamic acid, aspartic acid, glycine, leucine, alanine, lysine, and arginine. The abundant free amino acids in the FSM-added group were taurine, glutamic acid, alanine, leucine, and arginine. Six free sugars were found in all groups. Glucose was predominant, followed by mannose, rhamnose, fucose, fructose, and ribose. Among the three organic acids in the whole body of black rockfish, lactic acid was predominant, followed by citric acid and oxalic acid. Total organic acid content in the control was significantly higher than those of FSM substitution groups.

Psoraleae semen Extract Inhibits Angiogenesis and Adipogenesis

Ethanol extracts of Psoraleae semen (PSE) are used in Korean folk medicine for tuberculostasis, nycturia, sarcoma, inflammation, and cancer. We investigated the utility of P. semen extract for the suppression of angiogenesis and adipogenesis. Eighteen natural products were screened using anti-angiogenesis experiments, and one candidate product was identified. Psoraleae semen provided dosedependent inhibition of angiogenesis, adipogenesis, and cell adhesion in vitro and weight loss in mice in vivo. The anti-angiogenenic efficacy of PSE was superior to that of epigallocatechin gallate (EGCG) obtained from green tea leaves. The expression of angiogenesis and adipogenesisrelated signal molecules was reduced by increasing the doses of PSE. A diet supplemented with PSE provided more effective weight loss in LB mice than did orlistat, a representative synthetic diet drug, which also caused hairloss in LB mice. P. semen may be a useful antiadipogenic compound if these in vitro results are replicated under in vivo conditions.