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

• Korean journal of food and cookery science
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• v.5 no.2
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• pp.27-34
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• 1989

In the present study, the oxidative stability of Korean evening primrose oil (EPO) stored in various conditions, i.e., dark, cool, fluorescent light and daylight irradiation were investigated. Furthermore difference between the compositional content of gamma-linolenic acid (GLA) of EPO and that of alpha-linolenic acid of soybean oil (SOY) undergoing various modes of oxidation was observed. The results of the present study were as follows: More rapid autoxidative reations of EPO than that of SOY in vairous conditions increased in order of daylight, fluorescent light, cool and dark. Espectially, autoxidative rates of EPO increased rapidly on exposure to daylight and fluorescent light. This probably was due to chlorophyll functioned as a photosensitizer resulting in rapid oxidation of the EPO during irrdadiation of light. However, there was no difference between compositional content of GLA in EPO and alpha-linolenic acid in SOY undergoing various modes of oxidation. Therefore, theripid oxidative rate of EPO could be due to the catalytic effect of the chlorophyll on the photoxidation and the free radical reaction of PUFA.

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.232-239
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• 2016

Recently, research has been focusing on high quality and safer animal production by utilizing natural functional materials. The aim of this study was to evaluate the effect of administration of natural Evening Primrose Oil (EPO) on gamma linolenic acid (GLA) levels in milk from Holstein dairy cows. Quality and quantity of milk as well as blood and fatty acids from Holstein cow fed diets supplemented with 2.7-4% calcium-salted EPO coated with palm stearin oil were analyzed. There was no significant difference in yield and composition of milk between control and EPO treatment. However, EPO treatment lowered blood aspartate aminotransferase (AST), somatic cell count (SCC), and cholesterol levels (p < 0.05) compared to untreated control. Blood urea nitrogen (BUN) level was decreased (p < 0.05) in GLA 1 and GLA 2 group when compared with control group. Non-esterified fatty acids (NEFA) concentration was lower (p < 0.05) in GLA 1 and GLA 2 groups than in control group. The level of GLA in milk was increased in EPO group when compared to control. Therefore, results from the present study demonstrate that supplementary EPO has beneficial effects on cow health, showing a decrease in somatic cell count and levels of blood cholesterol, alanine aminotransferase (ALT), and AST. Furthermore, supplementation of EPO improves milk quality with increased amounts of GLA.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.884-889
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• 1989

Weanling male Sprague-Dawley rats were divided into 4 groups according to the level of plasma cholesterol and then fed diets containing 15%(w/w) corn oil, lard or evening primrose oil (EPO) with 0.5% (w/w) of cholesterol. Corn oil without cholesterol was used as a dietary lipid source of control diet. After 4 weeks of feeding, the fatty acid compositions of the red blood cell membrane and aorta phospholipids were analyzed together with the plasma cholesterol level. The rats fed with EPO characterized by its content of gamma-linolenic acid (GLA) showed lower cholesterol concentration in plasma than the other groups . In the corn oil groups, plasma cholesterol level was not affected by the addition of dietary cholesterol. The concentrations of dihomogamma-linolenic acid and arachidonic acid, metabolites of GLA, in the tissue were increased in the EPO group compared with the other groups.

• Journal of Microbiology and Biotechnology
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• v.21 no.7
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• pp.697-702
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• 2011

A strain of the cyanobacterium Arthrospira was isolated from Lake Chahannaoer in northern China and was characterized according to microscopic morphology, photosynthetic oxygen-evolving activity, growth rate, and nutritional profile. Compared with thermophilic Arthrospira species occurring naturally in tropical and subtropical lakes, this isolate is mesophilic and grows optimally at ${\sim}20^{\circ}C$. The total protein, fatty acid, phycocyanin, carotenoid, and chlorophyll a contents were 67.6, 6.1, 4.32, 0.29, and 0.76 grams per 100 grams of dry weight, respectively. The strain is rich in polyunsaturated fatty acids (PUFAs). An essential omega-3 fatty acid, docosahexaenoic acid (DHA), was detected, and ${\gamma}$-linolenic acid (GLA) and DHA accounted for 28.3% of the total fatty acid content. These features of this newly isolated strain make it potentially useful in commercial mass culture in local areas or as a biofuel feedstock. It is also an alternative resource for studying the metabolic PUFA pathways and mechanisms of cold stress tolerance in cyanobacteria.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.745-752
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• 2007

This study examined the effects of different levels of evening primrose oil (EPO) on the accumulation of ${\gamma}$-fatty acids in broiler meat. Six hundred one-day-old male chicks (Ross strain) from commercial broilers were divided randomly into 6 groups${\times}$4 repeat pens. The broilers were fed experimental diets containing 4.0% tallow (control), 0.5% EPO, 0.7% mixed oil (EPO 70:soy bean oil 30), 1.5% EPO, 3.0% EPO or 4.0% EPO for two weeks of broiler finisher. There was a significant difference in body weight gain between the control and treatment groups except for the 0.5% EPO group (p<0.05). There was a significant difference in the percentage of thigh and breast weight against the carcass weight between control and treatment groups except for the 0.5% EPO group in the thigh and 0.5% EPO and 4.0% EPO groups in the breast weight (p<0.05). The saturated fatty acid levels of the skin and breast muscle lipid of the broilers fed diets containing EPO were significantly lower than that of the control group (p<0.05), while the level of unsaturated fatty acid was significantly higher than that of the control group (p<0.05). The ${\gamma}$-fatty acid (GLA, gamma.linolenic acid, 18:3n-6) level was particularly higher in the chicken meat lipids from the broilers fed EPO than in the control group (p<0.05). This shows that feeding EPO to chicks can produce novel functional broiler meat that is enriched in gamma-linolenic acid.

• Reproductive and Developmental Biology
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• v.38 no.3
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• pp.129-136
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• 2014

This study was carried out to elucidate the effect of antibiotic-free rearing system(ARS) on cortisol level, stress hormone, and fatty acid content in the edible muscle tissues, that were of M. longissimus in Hanwoo. These cattle were reared in two different systems including antibiotic-free (ARS) and conservative system (CRS). To increase the experimental reliability, the muscle samples were purchased 3 times from 3 Korean brands of beef produced with ARS or CRS. In the muscle tissue, cortisol level was significantly lower in ARS than CRS, (p=0.0176). But the levels of total saturated- and unsaturated-fatty acids were not significantly different between ARS and CRS (p>0.05). Of total fatty acids, the total saturated fatty acid tended to be greater in CRS and the total unsaturated fatty acid tended to be greater in ARS. However, of the total unsaturated fatty acids, the level of n-6 unsaturated fatty acids was significantly higher in ARS than CRS (p=0.0040). Especially, ${\alpha}$-linolenic acid (ALA) and ${\gamma}$-linolenic acid (GLA) levels were significantly higher in ARS (p<0.01). The n-6 fatty acid content and cortisol level in muscle tissue were negatively correlated at p=0.0140. In conclusion, ARS may produce beef with higher quality which contains lower cortisol and greater n-6 fatty acids, such as ALA and GLA.

• Journal of Animal Science and Technology
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• v.55 no.2
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• pp.147-153
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• 2013

Lipid metabolism in mature male mice may be different from immature male mice, but the relationship of lipid metabolism, especially n-6 fatty acid metabolism, and sexual maturation is not clearly established. This study was carried out to elucidate whether sexual maturation may affect the metabolism of functional n-6 fatty acids of lipid components by investigating the composition of fatty acids in the longissimus muscle tissues of mature and immature male mice with GC and analyzing the expression of genes and proteins for synthesis of n-6 fatty acids with real-time PCR and western blotting, respectively. Mature male mice showed significantly higher testosterone level in the sera. Similarly, n-6 fatty acids, levels of linoleic acid (LA 18:2n-6) and total n-6 PUFA (Polyunsaturated fatty acids) were increased, but the levels of ${\gamma}$-linolenic acid (GLA; 18:3n-6), dihomo-${\gamma}$-linolenic acid (DGLA; 20:3n-6) and arachidonic acid (AA; 20:4 n-6) were decreased in the mature male mice. mRNA levels of ${\Delta}5$-desaturase (FASD1) and elongase (ELOVL5) genes related to n-6 fatty acid metabolism increased. However, the level of FADS1 protein only increased in mature male mice. In conclusion, this study suggested that sexual maturation of male mice affected n-6 fatty acid metabolism by stimulating the expression of enzyme FADS1 of n-6 PUFA metabolism.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.628-632
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• 2013

Arthrospira platensis (A. platensis) is an economically important microalgae because it has carbohydrates, lipids, proteins and a number of phytochemicals. It is also a valuable source used in the production of biodiesel and functional foods. In this study, A. platensis was exposed to electron beam irradation (240 kGy) and induced random mutagenesis for strain improvement. Several mutants were obtained, and the resulting mutant was designated as EB29. The growth rate and chlorophyll content of EB29 was similar to those of wild type. However, the lipid content of EB29 was increased seven-fold compared to that of wild type when comparing the nile red fluorescent intensity. Semi-quantitative analysis of EB29 using the calibration plot of standard lipid, triolein, represented $78.6{\mu}g/mL$, which increased 2 times compared to wild type ($41.4{\mu}g/mL$). When analyzing the fatty acid profile of EB29, polyunsaturated fatty acids (PUFAs), such as gamma-linolenic acid (GLA) in EB29 increased about six-fold. Moreover, fatty acids affecting the quality of biodiesel increased compared to that of wild type. Thus, electron beam could be used for the strain improvement of microalgae in order to accumulate PUFAs and alteration of fatty acid profile for biodiesel.

• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.669-675
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• 2015

This study was carried out to elucidate the effect of different rearing system on cortisol level, stress hormone, and fatty acid composition in the edible muscle tissues. These steers were reared in two different systems including antibiotic-free (ARS) and conservative system (CRS). In the M-Longissimus tissue, cortisol level was significantly lower in ARS than CRS, (p=0.0176). But, the levels of total saturated and unsaturated-fatty acids does not differ in ARS as CRS (p >0.05). However, the total saturated fatty acid levels tended to be greater in CRS and the total unsaturated fatty acid levels tended to be greater in ARS. However, the level of n-6 unsaturated fatty acid was higher in ARS than CRS (p=0.004). Especially, levels of linoleic acid (LA) and ${\gamma}$-linolenic acid (GLA) were significantly higher in ARS (p <0.01). Cortisol level and the n-6 fatty acid content in muscle tissue were negatively correlated (at p=0.00140.) In conclusion, ARS may produce beef with higher quality which contains lower cortisol and greater n-6 fatty acids, such as ALA and GLA.