Doo-Seog Lee

Comparison on proximate composition and nutritional profile of red and black sea cucumbers (Apostichopus japonicus) from Ulleungdo(Island) and Dokdo(Island), Korea

The proximate composition, fatty acid, and amino acid profile of the body wall and viscera of each red and black sea cucumber (Apostichopus japonicus) from Ulleungdo(Island) and Dokdo(Island) in Korea were compared. Moisture, ash, crude protein, and crude lipid contents ranged between 80.26–91.49, 2.57–6.85, 1.13–3.99, and 0.14–2.12%, respectively. The fatty acid values varied depending on the species and the regions of collection. The anteiso C17:0, C16:1Δ9, C17:1Δ7, C18:1Δ11, and C16:2Δ7 were only observed in the body wall. Among the tested fatty acids, the C18:1Δ11 was specific in red sea cucumber, and C20:4Δ6 (17.7%) and C20:5Δ3 (17.6%) were the predominant polyunsaturated fatty acids (PUFA) in all samples. The contents of the C18:0 dimethyl acetal (C18:0 DMA), C16:1Δ7, C16:1Δ5, and C18:1Δ5 were compared in details. Total amino acids (TAA) of body wall were 1.3–1.9 times higher than those of viscera. Glutamic acid and aspartic acid constituted the major TAA of sea cucumbers. The ratio of essential amino acids (EAA): nonessential amino acids (NEAA) on TAA ranged from 1.15 to 0.67 of sea cucumbers. Viscera of red sea cucumber from Dokdo(Island) were rich in free amino acids (FAA) and showed a high content in leucine.

Dipeptide (Tyr-Ile) Acting as an Inhibitor of Angiotensin -I-Converting Enzyme (ACE) from the Hydrolysate of Jellyfish Nemopilema nomurai

The jellyfish Nemopilema nomurai was hydrolyzed with papain and a novel dipeptide purified via ultrafiltration, gel filtration chro matography with Sephadex LH-20, and reverse phase chromatography using C 18 and C 12 columns. The IR, 1H NMR, 13C NMR, and MS spectrometer analyses showed that the dipeptide comprised tyrosine-isoleucine (Tyr-Ile). The IC 50 and K i values were 6.56

Purification and characterization of angiotensin-1 converting enzyme (ACE)-inhibitory peptide from the jellyfish, Nemopilema nomurai

The Nemopilema nomurai hydrolysate was produced by the reaction of papain, and an angiotensin-Ι converting enzyme (ACE)-inhibitory peptide was purified by using the molecular cut-offs membrane filter, the gel filtration chromatography with Sephadex LH-20 and the reverse phase chromatographic method using C 18 and C 12 columns. Purification yield of the active peptide was estimated to be 0.2 ± 0.1%, starting from the lyophilized jellyfish. The infrared (IR), proton nuclear magnetic resonance spectroscopy (1H NMR), carbon nuclear magnetic resonance (13C NMR) and mass spectrometry (MS) spectrometer analyses elucidated that the structure of the purified peptide is tyrosine-isoleucine (Tyr-Ile). The inhibitory concentration at 50% (IC50) and Ki values were calculated to be 2.0 ± 0.3 μg/ml and 3.3 ± 0.3 μM, respectively, which acts as a competitive inhibitor to ACE. Keywords : Angiotensin-Ι converting enzyme, Jellyfish, Nemopilema nomurai , Papain hydrolysate, Tyrosine-Isoleucine African Journal of Biotechnology Vol. 12(15), pp. 1888-1893

ACE-Inhibitory Properties of Proteolytic Hydrolysates from Giant Jellyfish Nemopilema nomurai

This study aimed to determine the degree of hydrolysis and angiotensin-I-converting enzyme (ACE)-inhibitory activity of Giant Jellyfish Nemopilema nomurai (jellyfish) hydrolysates. The degree of hydrolysis using six proteolytic enzymes (Alcalase, Flavo zyme, Neutrase, papain, Protamex, and trypsin) ranged from 13.1-36.8% and the inhibitory activities from 20.46-79.58%. Using papain hydrolysate, we newly isolated and characterized ACE-inhibitory peptides with a molecular weight of 3,000-5,000 Da that originated from jellyfish collagen. The purified peptide (FII-b) was predicted to be produced from an alpha-2 fragment of the type IV collagen of jellyfish. The N-terminal sequence of FII-b was Asp-Pro-Gly-Leu-Glu-Gly-Ala-His-Gly- and showed 87% identity to the collagen type IV alpha-2 fragment of Rattus norvegicus and a predicted protein from Nematostella vectensis, indicating that the ACE-inhibitory peptide originated from the collagen hydrolysate and had an IC 50 value of 3.8 μg/mL. The primary structure of the fragment is now being studied; this peptide represents an interesting new type of ACE inhibitor and will provide knowledge of the potential applications of jellyfish components as therapies for hypertension.

Evaluation of Bacteriological Safety for the Shellfish growing Sea waters in Seocheon Area, Korea

【A Sanitary survey in an Important shellfish-growing area of Biin Bay in Seocheon-gun Korea, was conducted to evaluate bay conditions and compliance with the bacteriological criteria for areas designated for the production of shellfish for export. Seawater samples were collected monthly at 55 sampling stations established in the survey area from January 2006 to December 2008. Bacteriological water quality did not change in response to a small rainfall (10.0 mm), but it increased abruptly in response to rainfall to 62.5 mm The most probable number (MPN) value for total coliforms and fecal coliforms in 1, 980 seawater samples ranged from 1, 600 MPN/100mL and from

Proximate and Fatty Acid Compositions of 14 Species of Coastal and Offshore Fishes in Korea

90^{th}

Antioxidant and Cholinesterase Inhibitory Activities of Aqueous Extract from Rainbow Trout Oncorhynchus mykiss

percentile value for total coliforms ranged from 2.0 to 10.3 MPN/100mL and from 7.0 to 42.6 MPN/100mL respectively. The geometric mean and estimated percentile value for fecal coliforms ranged from 1.8 to 4.0 MPN/100mL and from 1.9 to 18.3 MPN/100mL, respectively. Accordingly, the bacteriological water quality of Biin Bay met the National Shellfish Sanitation Program (NSSP) and Korea Shel1fish Sanitation Program(KSSP) criteria for areas designated for shellfish production for export in Korea.】

Proximate and Fatty Acid Compositions of Three Species of Imported and Domestic Freshwater Fishes

Proximate and fatty acid compositions in muscle tissue were studied in 14 species of coastal and offshore fishes in Korea. Lipid content ranged from 0.57 to 10.5% and was higher in migratory and reef dwelling fishes than in de-mersal fishes. Protein content ranged from 14.4 to 20.3% and moisture content ranged from 72.4 to 81.8% in all fish samples. There was a negative correlation between lipid and moisture content in all fish samples (r= -0.90, P<0.001). The prominent fatty acids were 16:0, 22:6n-3 (docosahexaenoic acid, DHA), 18:1n-9, 20:5n-3 (eicosapentaenoic acid, EPA), 16:1n-7, 18:0 and 18:1n-7. Most demersal fishes contained considerably higher amounts of 20:4n-6 and/or 22:5n-3 compared with migratory and reef dwelling fishes. The proportion of total polyunsaturated fatty acid (PUFA), including DHA and EPA, was higher in demersal fishes (38.6-54.0%) than in migratory and reef dwelling fishes (23.5-35.2%).Key words: Docosahexaenoic acid, Eicosapentaenoic acid, Fish, Lipid, PUFA

Mineral Content and Nutritional Evaluation of Fishes from the Korean Coast

We investigated the antioxidant and cholinesterase inhibitory activities of the aqueous extract of rainbow trout Oncorhynchus mykiss. The antioxidant activity of O. mykiss aqueous extract was determined by in vitro peroxynitrite scavenging activity and reducing power assays. The aqueous extract of O. mykiss showed potent peroxynitrite radical scavenging activity (IC50=0.12 ± 0.001 mg/mL) and reducing power (absorbance=0.47 ± 0.001) at the concentration of 1 mg/mL. The in vitro cholinesterase inhibitory activity of O. mykiss aqueous extract was examined using spectrophotometric analyses of acetyl- and butyrylcholinesterase. The aqueous extract of O. mykiss showed acetylcholinesterase inhibitory activity (IC50=1.61 ± 0.13 mg/mL), but did not exhibit inhibitory activity against butyrylcholinesterase. These results suggest that O. mykiss possesses antioxidant and acetylcholinesterase inhibitory activities and provide scientific evidence for the health benefits of O. mykiss aqueous extract.

Proximate Composition and Nutritional Evaluation of Fisheries Products from the Korean Coast

The proximate and fatty acid compositions of the edible portion of three species of cultured freshwater fish (common eel Anguilla japonica, rainbow trout Onchorhynchus mykiss, and Israeli carp Cyprinus carpio) were compared between imports from China and domestically produced specimens. The lipid contents of cultured common eel and rainbow trout were rich in imported fishes (20.4 and 12.2%, respectively) compared with those in domestic ones (16.0 and 8.01%, respectively), while those of Israeli carp were rich only in the domestically produced specimens (8.06 and 3.07%, respectively). There was a negative correlation between the lipid and moisture contents in all fish samples (r