• Fisheries and Aquatic Sciences
• /
• v.8 no.2
• /
• pp.43-50
• /
• 2005

We evaluated the nutritional composition of the siphon of the surf clam Tresus keenae in regard to the presence of nitrogenous [amino acids, nucleotides and their related compounds, total creatinine, betaine, trimethylamine oxide (TMAO), and trimethylamine (TMA)] and non­nitrogenous compounds (sugars and organic acids), lipid fatty-acid composition, and occurrence of minerals. The content of total free amino acids was 660.27 $\pm$ 7.94 mg/100 g, and the predominant amino acids were arginine, alanine, sarcosine, glycine, and glutamic acid. These amino acids accounted for $71\;\%$ of the total free amino acids. Among the nucleotides and their related compounds, inosine was the major component and comprised 40.38 $\pm$ 0.02 mg/100 g. Free amino acids were the largest contributor to total extracted nitrogen, comprising $49.94\%$, followed by total creatinine, betaine, nucleotides, and ammonia; the contribution of TMAO and TMA was small. For the non-nitrogenous compounds, malic acid, propionic acid, and succinic acid comprised the major portion of the ten kinds of organic acids detected, and the sugars found were glucose, maltose, and arabinose, which were estimated to be $147.0\pm7.15,\;34.45\pm1.09,\;and\;1.21\pm0.02\;mg/100\;g,$ respectively. The predominant minerals were Na and K, which comprised $11.43\pm1.06\;and\;9.46\pm1.02\;mg/100\;g,$ respectively. The major fatty acids were C22:6, C20:5, C23:0, C18:3, and C16:0 in the lipid fractions. The 23:0 level of glycolipid (GL) was the highest of any other lipid fraction. The amount of total polyunsaturated fatty acids (PUFA) in the lipid fractions was higher, ranging from $58.22\%\;in\;GL\;to\;77.1\%$ in phospholipid (PL), compared to the saturated and monounsaturated fatty acids. Of the n-3 fatty acids, C20:5 and C22:6 contributed $35.30-64.44\%$ of PUFA in the lipid fractions. The ratios of n-3 to n-6 PUFA in total lipid (TL), neutral lipid (NL), PL, and GL were 4.35, 4.26, 6.69, and 2.04, respectively.

• Fisheries and Aquatic Sciences
• /
• v.9 no.2
• /
• pp.49-56
• /
• 2006

We evaluated changes in the nutritional composition of Mideodeok Styela clava harvested during the months of January, March, and May 2005. Glutamic acid, aspartic acid, arginine, leucine, and lysine were the most dominant amino acids present. Ratios of essential amino acids to nonessential amino acids were comparable to those of many fish species, with values ranging from 0.55 to 0.61 and 0.66 to 0.67 for muscle of Mideodeok from Geoje and Tongyeong, respectively. Mideodeok seems to be a suitable source of important fatty acids as it contains high levels of polyunsaturated fatty acids. Eicosapentanoic acid EPA; 20:5n-3 and docosahexanoic acid DHA; 22:6n-3 were the most dominant fatty acids, ranging from 20.0 to 22.3% and 16.5 to 17.9% in muscle, and 20.3 to 23.2% and 15.2 to 18.8% in tunic, respectively. The total mineral fraction of Mideodeok was 22.2-27.3% of dry matter. Sodium, calcium, magnesium, and potassium were the most dominant minerals in both muscle and tunic.

• Journal of the Korean Society of Food Culture
• /
• v.23 no.3
• /
• pp.397-402
• /
• 2008

This study was conducted to evaluate the quality characteristics of domestic as well as imported fermented skate. Three types of fermented skate products were analyzed for proximate composition, pH, VBN, ammonia-N, free amino acids, and fatty acids. The results indicated that the domestic fermented skate contained large amounts of TMAO. Also, the domestic and imported fermented skates each contained approximately 7.1 log CFU/g and $5.8{\sim}6.5$ log CFU/g of aerobic bacteria, respectively, and 585.9 mg and $384.1{\sim}398.5$ mg of total free amino acids, respectively; all samples contained high levels of taurine, anserine, lysine, alanine, glycine, proline, and ${\beta}-alanine$. For fatty acid composition, the domestic fermented skate contained 11 different types of saturated fatty acid and 16 types of unsaturated fatty acid, whereas the imported skate contained 8 types of saturated fatty acid and $10{\sim}15$ types of unsaturated fatty acid. Overall, the results suggest that domestic fermented skate is a better source of amino acids and essential fatty acids and contains more aerobic bacteria than imported fermented skate.

• Fisheries and Aquatic Sciences
• /
• v.4 no.4
• /
• pp.246-251
• /
• 2001

As a series of studies on improving quality of seasoned-dried Pacific saury, fatty acid compositions and taste compounds of the seasoned-dried saury treated with liquid smoke (T2 product) were examined during storage, comparing with control (C, seasoning only). In the both samples, the major fatty acids were 22:6n-3, 16:0, 22: In-11I, 20: In-11, 18: In-9, 14:0, 20:5 n-3 and 16:1n-7. The contents of saturated fatty acids in C and T2 increased with increasing storage period, while those of polyunsaturated fatty acids decreased. After drying, the contents of 7 non-volatile organic acids contents detected in this study decreased, and the others of non-volatile organic acids, except for malic and citric acids, in both C and T2 decreased with storage period. The contents of nucleotides and their related compounds in both C and T2 decreased with increasing storage period. The content of total free amino acids in raw sample was 556.96 mg/100g and increased up to 895.77 mg/l00 g and 958.40 mg/100g in C and T2, respectively, after drying, and total contents of free amino acids in both C and T2 somewhat decreased after 60 days of storage.

• Food Science of Animal Resources
• /
• v.42 no.1
• /
• pp.18-33
• /
• 2022

Beef contains functional fatty acids such as conjugated linoleic acid and longchain fatty acids. This review summarizes results from studies comparing the fatty acid composition of beef from cattle fed either grass or grain-based feed. Since functional lipid components are contributed through dietary consumption of beef, the fatty acid composition is reported on mg/100 g of meat basis rather than on a percentage of total fat basis. Beef from grass-fed contains lesser total fat than that from grain-fed in all breeds of cattle. Reduced total fat content also influences the fatty acid composition of beef. A 100 g beef meat from grass-fed cattle contained 2,773 mg less total saturated fatty acids (SFA) than that from the same amount of grain-fed. Grass-fed also showed a more favorable SFA lipid profile containing less cholesterol-raising fatty acids (C12:0 to C16:0) but contained a lesser amount of cholesterol-lowering C18:0 than grain-fed beef. In terms of essential fatty acids, grass-fed beef showed greater levels of trans-vaccenic acid and long-chain n-3 polyunsaturated fatty acids (PUFA; EPA, DPA, DHA) than grain-fed beef. Grass-fed beef also contains an increased level of total n-3 PUFA which reduced the n-6 to n-3 ratio thus can offer more health benefits than grain-fed. The findings signify that grass-fed beef could exert protective effects against a number of diseases ranging from cancer to cardiovascular disease (CVD) as evidenced by the increased functional omega-3 PUFA and decreased undesirable SFA. Although grain-fed beef showed lesser EPA, DPA, and DHA, consumers should be aware that greater portions of grain-fed beef could also achieve a similar dietary intake of long-chain omega-3 fatty acids. Noteworthy, grain-fed beef contained higher total monounsaturated fatty acid that have beneficial roles in the amelioration of CVD risks than grass-fed beef. In Hanwoo beef, grain-fed showed higher EPA and DHA than grass-fed beef.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.8
• /
• pp.1214-1219
• /
• 2008

This study was conducted to evaluate the effect of supplementing tuna oil to diets of growing-finishing pigs (barrows and gilts) on backfat characteristics when slaughtered at different weights. Four hundred and eighty crossbred (Large White$\times$Landrace$\times$Duroc) pigs averaging 30 kg were allotted to 12 treatment combinations (40 pigs/treatment combination) in a completely randomized design with a $2{\times}2{\times}3$ factorial arrangement of treatments. The treatments were: dietary tuna oil supplementation (0 and 2%); sex (barrows and gilts); and slaughter weight (90, 100 and 110 kg). As pigs reached their slaughter weight, they were randomly selected (8 pigs/treatment combination; 96 pigs in total) and slaughtered. Backfat colour, hardness and fatty acid profile were assessed. There were significant (p<0.05) differences in colour (L* and a* values) among treatments. Backfat of the control group was harder than on the tuna oil (p<0.001) and that of barrows was harder than of gilts (p<0.05). In addition, the thiobarbituric acid reactive substances (TBARS) values of fat from the tuna oil group stored for 3 days were higher (p<0.001) than the control group. The TBARS values of gilts tended to be higher than those of barrows and increased with increasing slaughter weight in the tuna oil group. The cholesterol and triglyceride levels were not affected by diet and sex but the triglyceride level increased with increasing slaughter weight (p<0.01). The tuna oil group had higher polyunsaturated fatty acid (PUFA) content, ratio of PUFA: saturated fatty acid (SFA) and total n-3 fatty acids but lower monounsaturated fatty acids content and n-6:n-3 fatty acids than the control group (p<0.01). Gilts had higher PUFA and n-6 fatty acids in backfat than barrows (p<0.05). The backfat from both 90 and 100 kg slaughter-weight groups had a lower ratio of n6:n3 fatty acid than the 110 kg slaughter-weight group (p<0.05). However, this was more pronounced in the tuna oil group. The PUFA: SFA was also increased while the n-6:n-3 ratio tended to reach the recommended levels for healthy eating in human beings of <5. However, due to oxidative susceptibility, barrows should not be slaughtered at more than 100 kg for the meat to be acceptable to consumers.

• Fisheries and Aquatic Sciences
• /
• v.18 no.4
• /
• pp.359-365
• /
• 2015

We investigated the effects of dietary lipid sources on growth and fatty acid composition of juvenile Chinese longsnout catfish. Triplicate groups of fish (initial average weight, 3.8 g) were fed four diets containing either fish oil (FO), soybean oil (SO), linseed oil (LO) and lauric acid (LA) for 10 weeks. There were no differences among the groups in body weight, feed intake, feed efficiency, protein efficiency ratio, and body proximate composition of fish fed the diets containing different lipid sources (P > 0.05) during the study. However, fatty acids compositions of the whole body were influenced by dietary lipid source. Fish fed the SO diet had high concentration of linoleic acid, whereas those of fish fed the LO diet were rich in linolenic acid and arachidonic acid. Fish fed the FO diet had significantly (P < 0.05) higher levels of monounsaturated fatty acids such as 18:1n-9 and 20:1n-9 than those of fish fed the SO and LO diets. Eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) composition of body were not influenced by dietary lipid source. The results suggest that each of FO, SO, LO or LA can be used as a lipid source in the diets of Chinese longsnout catfish without any negative effects on growth and feed utilization and these data demonstrate the potential impact which dietary fat composition can change the body fatty acid profile.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.10
• /
• pp.1098-1102
• /
• 2009

Gamma-linolenic acid (GLA, C18:3 ${\Delta}^{6,9,12}$) is synthesized by a delta-6 fatty acid desaturase using linoleic acid (LA, C18:2 ${\Delta}^{9,12}$) as a substrate. To enable the production of GLA in the conventional yeast Pichia pastoris, we have isolated a cDNA encoding the delta-6 fatty acid desaturase from Cunninghamella echinulata MIAN6 and confirmed its function by heterogeneous expression in P. pastoris. Sequence analysis indicated that this cDNA sequence has an open reading frame of 1,404 bp, which encodes a 52 kDa peptide of 468 amino acids. This sequence has 64% identity to the previously reported delta-6 fatty acid desaturase from Rhizopus oryzae. The polypeptide has a cytochrome b5 domain at the N-terminus including the HPGG motif in the heme-binding region, as reported for other delta-6 fatty acid desaturases. In addition, this enzyme differs from other desaturases by the presence of three possible N-linked glycosylation sites. Analysis of the fatty acid composition demonstrated the accumulation of GLA to the level of 3.1% of the total fatty acids. Notably, the amounts of ginkgolic acid (C17:1) and palmitic acid (C16:0) were increased from 1.3% to 29.6% and from 15% to 33%, respectively. These results reveal that the modification of the fatty acid biosynthetic pathway by genetic manipulation in order to produce specific polyunsaturated fatty acids in P. pastoris is a promising technique.

• Food Science of Animal Resources
• /
• v.35 no.1
• /
• pp.10-18
• /
• 2015

The changes in fatty acid composition of total intramuscular lipid and phospholipids were investigated in the longissimus dorsi, left-hind leg muscle, and abdominal muscle of male Ira rabbits. Changes were monitored at 35, 45, 60, 75, and 90 d. Analysis using gas chromatography identified 21 types of fatty acids. Results showed that the intramuscular lipid increased and the intramuscular phospholipids (total intramuscular lipid %) decreased in all muscles with increasing age (p<0.05). An abundant amount of unsaturated fatty acids, especially polyunsaturated fatty acids, was distributed in male Ira rabbits at different ages and muscles. Palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), and arachidonic acid (C20:4) were the major fatty acids, which account to the dynamic changes of the n-6/n-3 value in Ira rabbit meat.

• Journal of Nutrition and Health
• /
• v.24 no.3
• /
• pp.179-188
• /
• 1991

Twenty college women were led experimental diet which composed ot basal diet plus different kinds of dietary rats at 27% Cal. Equal amount of 13.5g of corn oil, perilla oil or fish oil was supplied for 2 weeks as a source of n6 linoleic acid(LA). n3 $\alpha$-linolenic acid (LL). or n3 EPA + DHA. respectively. Plasma total Chol level was reduced by perilla and fish oils, significantly only by fish oil. Plasma Chol level was rather increased by corn oil(P<0.05), but was decreased by double amount of corn oil supplement. Therefore, hypocholesterolemic effect of fatty acids was in the order of n3 EPA+DHA>n3 LL>n6 LA and influenced by the degree of fat unsaturation. Plasma TG level was also significantly decreased by n3 EPA+ DHA and increased by n6 LA. Hypotriglyceridemic effect of fatty acids was also in the order of n3 EPA + DHA> n3 LL>n6 LA and influenced by the unsaturation. However, the reduction of plasma TG was more influenced by the fatty acid structure rather than the fat unsaturation. There were no significant effects on lipoprotein pattern 3nd chemical compositions of lipoprotein by different dietary PUFAs. but fish oil diet significantly increased the relative proportion of HDL-Chol. In conclusion. cholesterol- lowering effect of dietary PUFAS seemed to be a function of total fat unsaturation but hypotriglyceridemic effect seemed to be more linked to the ratty acid structure rather than the degree of unsaturation. The hypolipidemic effect of n3 PUFAs was significant so that fish oil or perilla oil may have important nutritional applications in the prevention and treatment of atherosclerotic disease.