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【The proximate, fatty acid and dimethyl acetal (DMA) compositions of domestic and imported melania snails Semisulcospira sp. being sold commercially were studied. The protein content ranged from 8.09% (China) to 11.3% (North Korea). The lipid content ranged from 0.84 (China) to 2.36% (North Korea). Domestic melania snail had protein (10.5%) and lipid (1.02%) contents intermediate between those of the two imported melania snails. The prominent fatty acids were 16:0 and 18:0 saturated fatty acids, 16:1n-7, 20:1n-11, 18:1n-9, 18:1n-7 and 16:1n-9 monounsaturated fatty acids, and 20:4n-6, 20:5n-3 (eicosapentaenoic acid, EPA), 22:2 non-methylene-interrupted diene (NMID), 18:3n-3, 18:2n-6 and 22:5n-3 (docosapentaenoic acid, DPA) polyunsaturated fatty acids (PUFA). The percentage of n-3 PUFA was higher in domestic (19.6%) and North Korean (imported, 19.5%) snails than in that from China (imported, 16.8%), while the n-6 PUFA level was higher in snails from China (21.2%) and domestic snails (14.7%) than in that from North Korea (9.87%). The total DMA, i.e., 18:0 DMA, 16:0 DMA and 18:1 DMA was 7.30, 7.27, and 4.86% domestic snail and those from China and North Korea, respectively. These results suggest that melania snail is a source of n-3 PUFA, and DMA derived from plasmalogen.】

The aim of this study was to investigate changes in the biochemical characteristics of the Pacific oyster Crassostrea gigas in response to boiling water bath (, ) and autoclaving () heat treatments for 5, 10, 15, and 20 min. The weight loss (7.6-9.5%) of oysters exposed to a boiling water bath for 15 min was lower compared to those receiving no treatment. Oysters exposed to the boiling water bath for 20 min lost 27.8% of their total weight. The autoclaving treatment resulted in weight loss of 13.0-26.1%, with the highest weight loss occurring after 10 min of treatment (26.1%). Heat-treated oysters had significantly higher levels of crude lipid and crude protein relative to untreated oysters (P boiling water bath and autoclaving treatments. The fatty acid composition of oysters was not significantly affected by the water bath heat treatment, but oysters treated with autoclaving for 20 min had decreased polyunsaturated fatty acids. Oysters exposed to the water bath heat treatment had significantly increased vitamin A content, but autoclaving for 20 min was associated with reduced vitamin A content, as compared to all of the other heat treatments. Therefore, oysters were affected by heat treatment, undergoing metamorphosis and weight loss, but nutrient quality did not change significantly compared to controls, except with the 20-min boiling water bath and autoclaving treatments.

The antioxidant and cholinesterase inhibitory activities of the acetone and dichloromethane (CH2Cl2) extracts of the by-products (heads, shells, and tails) of Pandalus borealis, Pandalus hypsinotus, and Pandalopsis japonica belonging to the family Pandalidae were investigated and their bioactivities were compared. The antioxidant and cholinesterase inhibitory activities of the organic solvent extracts of three shrimp by-products were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2´-Azino-bis[3ethylbenzothiazoline-6-sulfonic acid] (ABTS + ) radical scavenging activities, reducing power and xanthine oxidase (XO) inhibitory activity assays and Ellman’s colorimetric method. The extracts of P. hypsinotus exhibited the highest antioxidant and cholinesterase inhibitory activities. The acetone extracts showed more potent activities toward antioxidant and cholinesterase inhibition compared with the CH2Cl2 extracts. Furthermore, the total carotenoid contents of the acetone extracts were higher than those of the CH2Cl2 extracts. Thus, the carotenoid contents may affect antioxidant and cholinesterase inhibition. Our results suggest that the shrimp by-products could act as a nutraceutical agent to prevent oxidative stress and Alzheimer’s disease.

We investigated the antioxidant and angiotensin I converting enzyme (ACE) inhibitory activities of red snow crab Chionoecetes japonicas shell (RSCS) hydrolysate by enzymatic hydrolysis and its molecular weight cut-off fractions. The RSCS hydrolysate was fractionated through two ultrafiltration membranes of 3 and 10 kDa cut-offs. Three fractions ( 10 kDa) were evaluated for total amino acid composition, antioxidant activities using 2′-azino-bis[3-ethylbenzthiazoline-6-sulfonic acid] (ABTS + ) radical scavenging and superoxide dismutase (SOD)-like activities and reducing power assays, and ACE inhibitory activity using Hou’s method. Although all fractions showed activity, the

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

The proximate compositions and fatty acid profiles of Antarctic toothfish Dissostichus mawsoni that was caught in the southern Ross Sea (J, L) of the Antarctic Ocean were studied. The lipid contents of samples from J and L were 18.2 and 21.1%, respectively. The protein and ash contents were similar for samples J and L. The prominent fatty acids in the total lipids of the fish muscle were 18:1n-9, 16:1n-7, 16:0, 14:0, 18:1n-7, 20:5n-3 (eicosapentaenoic acid, EPA), and 22:6n-3 (docosahexaenoic acid, DHA). In addition, the total fatty acids of bycatch products in the toothfish stomachs (Pleuragramma antarcticum, Gerlachea australis, Pasiphaea sp., Trematomus eulepidotus, Chionodraco hamatus, Chionodraco myersi, and Neopagetopsis ionah) were determined. The prominent fatty acids in those species were 18:1n-9, 16:0, 14:0, DHA, EPA, and 18:1n-7.

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.

The biochemical composition of muscle from three deep-sea animals, Tanaka’s eelpout Lycodes tanakae magistrate armhook squid Berryteuthis magister , and ocean sunfish Mola mola caught in the East sea in South Korea was determined. The moisture (81.4-93.8 g/100 g), crude protein (5.0-15.6 g/100 g), crude lipid (0.1-1.5 g/100 g), and ash (1.0-1.1 g/100 g) contents of the two fishes were analyzed. The proximate composition of magistrate armhook squid was: moisture 84.0 g/100 g, crude protein 12.4 g/100 g, crude lipid 0.7 g/100 g, and ash 1.5 g/100 g. There was little difference in the proximate compositions of the three animals. The total amino acid contents of Tanaka’s eelpout, magistrate armhook squid,and ocean sunfish were 14.64, 10.75, 3.10-9.95 g/100 g, respectively. High levels of glutamic acid, aspartic acid, lysine, leucine, and arginine were found, while low levels of histidine, glycine, and cysteine were detected in the animals. A survey of the free amino acid contents of the animals revealed large amounts of alanine and glycine. Significant differences were found in the fatty acid composition among the three species. Specially, differ-ent saturated fatty acids (17.14-40.49%) such as C16:0, and C18:0, monounsaturated fatty acids (19.19-46.88%) such as C16:1, and C18:1, and polyunsaturated fatty acids (35.41-57.08%) such as EPA, and DHA was identified. Our results suggest that each of these deep sea animals possesses nutritional value and should be considered as a foodstuff.

✽ Food Safety Research Division, National Fisheries Research & Development Institute, Busan 619-705, Korea This study reviewed the effect of the drying conditions on the production of biogenic amines and lipid oxidation in semi-dried Pacifi c saury Cololabis saira or Guamegi. The moisture content of the Guamegi ranged from 32.71±2.37 to 45.9±2.60 g/100 g. The respective ranges of the acid value (AV) and peroxide value (POV) were 1.39±0.40 to 15.79±0.47 mg KOH/g and 76.14±2.19 to 282.84±2.34 meq/kg on drying for 3 days. The AV and POV increased for up to 3 days of drying and the values differed according to the amount of sunlight and temperature. However, lipid oxidation was reduced in Guamegi manufactured using a cold-air drying method. The fatty acid composition and the biogenic amine content in Guamegi during drying did not differ signifi cantly with the drying method or drying date. The main saturated, monoene and polyene fatty acids were palmitic acid, eicosenoic & erucic acids, and eicosapen- taenoic & docosahexaenoic acids, respectively. At 16.67 to 71.89 mg/kg, the histamine content was higher than that of other biogenic amines and it increased signifi cantly during drying. In conclusion, this study showed that the pack- aging and drying conditions of Guamegi products need to be improved to inhibit lipid oxidation and biogenic amine formation. Key word: Guamegi, Semi-dried Pacifi c saury, Lipid oxidation, Biogenic amine, Histamine

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.

To identify the food characteristics of seven melania snail species in Korea, the detailed proximate, fatty/amino acid, mineral composition and chlorophyll contents were investigated. The content ranges of moisture, crude protein, crude lipid and ash were 70.1-81.0%, 11.6-16.9%, 0.4-1.6% and 1.9-3.4%, respectively. K. nadifila showed the significant mineral contents Fe, P, Ca than other species. Total Chlorophyll level was highest in K. globus ovalis (1.2±0.2 mg/g). The major fatty acids were 16:0, 22:1, 20:1, 18:1, 20:5 and 22:6 were identified as small amounts (1.0-3.3%) of total fatty acids. Citrulline was shown to be the major free amino acids (20.4-53.1%).

Crude saponin, extracted from the starfish Asterias amurensis, was assessed for its capacity as a biological pesticide. As part of this analysis, its insecticidal and repellent activities, in addition to its acute and chronic toxicities were tested. In comparison with the control group, insecticidal activity of saponin against tobacco cutworm, Spodoptera litura, in kale, Brassica loeracea was low at 36.4%. Repellent activities of the extracted saponin against green peach aphid, Myzus persicae, and S. litura, on soybean leaf, Glycine max and kale were 65.6% and 35.0% at day, and 54.5% and 30.0% at day, respectively. Acute and chronic toxicity analysis was carried out using acute immobilizatioin test and reproduction impairment test, respectively. The saponin had 48 h- of . Twenty-one day accumulative reproduction after treatment was lower in Daphnia magna at $7{\mu}g/mL$ saponin (78 youngs), compared with the control group (129 youngs). These results indicate that the extracted saponin exhibited some toxicity and has potential as a repellent against insects.