• Proceedings of the Korean Society of Crop Science Conference
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• 1991.05a
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• pp.102-103
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• 1991

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.2
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• pp.182-188
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• 1988

In order to find out the effects of the time and degree of defoliation on the seed yield, oil content and fatty acid composition of perilla seed, two cultivars, Namhae and Geumnung, were grown in two years, 1985 and 1987. Defoliation was initiated after 110 days from sowing with two-week interval. Defoliation degree was manipulated into four levels i.e. 0, 25, 50 and 75 per cent based on the total leaf area per plant. The results are summarized as follows: Flowering date, maturing date, culm length, culm diameter and branch numbers were not significantly influenced by the defoliation time and degrees, but by the cultivars. The higher levels of defoliation was made, the lower seed yield and 1000-seed were obtained, and either the earlier or the later time of defoliation, the less influence on seed yield were observed for both cultivars. Severe defoliation caused a significant decrease in oil content. The composition of unsaturated and saturated fatty acids was significantly decreased by severe defoliation (above 25 per cent). In conclusion, with a view to achieving higher seed yield and oil content with good quality, it is advisable to defoliate perilla leaf less than 25 per cent based on total leaf area at either or later growth stages.

• Journal of Nutrition and Health
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• v.15 no.4
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• pp.277-289
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• 1982

Because of a high degree of unsaturation of perilla seed oil vitamin E deficiency can be produced in chicks by using this particular oil diet. It is therefore convenient to use this oil for elucidating more detailed function (s) of vitamin E. The present study was undertaken to investigate the nutritional and pathological aspects both of high PUFA and of low vitamin E in the diet eventually to elucidate the function(s) of vitamin E. The present study examines the relationships between PUFA, vitamin E and Se in the experimental diets by measuring vitamin E levels both in serum and in liver and activities of SGPT and SGOT and by examining electron micrographs of the chick hepatocytes. Vitamin E concentrations in serum and liver responded to dietary treatments. Serum levels of vitamin E were more affected than those in liver, the values of groups IV(15% fat,- Vit.E) and V(15% fat,-Vit E,-Se) were significantly lower than those of groups I (5% fat) and 111 (15% fat) with P/S ratio of 1. The activities of SGOT and SGPT were found not to be different significantly among different diet groups. Electron microscopic observations of the chick hepatocyte revealed degeneration of mitochondria and appearance of vesicles in the cytoplasm of groups fed diets high in PUFA and deficient in vitamin E alone or deficient in both vitamin E and Se. In the same group pyknotic nuclei and deterioration of the sinusoidal border, showing diminution in microvilli were also observed. More detailed studies concerning biochemical aspects should be carried out by using radioisotopes both in the in vitro and in vivo systems and morphological study should have a focus on the changes in nucleus which seems already suggestive in the present observation.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.21-26
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• 2015

Seasoned laver Pyropia spp. is a traditional Korean seafood that has gained popularity worldwide because of its unique taste, texture, and health benefits. It is prepared by roasting a sheet of dried laver, to which vegetable oils have been applied, at an ultra-high temperature (UHT) of $300^{\circ}C$. Therefore, the oxidative stability of the oils is the most important factor in determining the shelf life of seasoned laver products. In this study, we investigated changes in the thermal oxidative stability of six major vegetable oils (sesame, perilla, sunflower, rice bran, canola, and olive) during the seasoned laver processing. The oxidation induction time of each oil from the seasoned laver products was decreased compared with the fresh oil. These results indicate that the UHT treatment ($300^{\circ}C$, 10 s) induced thermal oxidation of the oils. Among the six seasoned laver oils, the induction times of olive (OL, 8.02 h) and sesame (SE, 5.31 h) oils were significantly higher than the other oils. The acid values (AVs) of OL and SE oils from the seasoned laver were 0.49 and 0.79, respectively. On the other hand, perilla oil had the overall worst thermal oxidative properties (induction time: 0.35 h, AV: 2.82). Our results provide useful information about seasoned laver products for researchers or manufactures.

• New & Renewable Energy
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• v.8 no.4
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• pp.30-37
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• 2012

Biodiesel was produced by "transesterification" of vegetable oils and animal fats as an alternative to petroleum diesel. The research analysed the fuel characteristics of biodiesel, the yield of by-products and biodiesel, using several vegetable oils - rapeseed oil, camellia oil, peanut oil, sesame oil, perilla oil, palm oil, olive oil, soybean oil, sunflower oil and animal fats such as lard, tallow, and chicken fat. The results showed the yields of biodiesel made from the vegetable oils and animal fats were $90.8{\pm}1.4{\sim}96.4{\pm}0.9%$ and $84.9{\pm}1.1{\sim}89.6{\pm}1.5%$ respectively. Production rates and oxidation characteristics were different depending on the fats applied.

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.158-165
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• 2012

This study was designed to investigate whether the fatty acid composition could make a significant contribution to the oxidation stability of vegetable oils marketed in Korea. Ten kinds, 97 items of vegetable oils that were produced in either an industrialized or a traditional way were collected and analyzed for their fatty acid compositions and lipid oxidation products, in the absence or presence of oxidative stress. Peroxidability index (PI) calculations based on the fatty acid composition ranged from 7.10 to 111.87 with the lowest value found in olive oils and the highest in perilla oils. In the absence of induced oxidative stress, malondialdehyde (MDA), the secondary lipid oxidation product, was generated more in the oils with higher PI (r=0.890), while the tendency was not observed when the oils were subjected to an oxidation-accelerating system. In the presence of the oxidative stress, the perilla oils produced in an industrialized manner generated appreciably higher amounts of MDA than those produced in a traditional way, although both types of oils presented similar PIs. The results implicate that the fatty acid compositions could be a predictor for the oxidation stability of the vegetable oils at the early stage of oil oxidation, but not for those at a later stage of oxidation.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.9-14
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• 1993

The free, ester and insoluble bound phenolic acids in the extracts from defatted perilla seed flour were isolated and their antioxidative activities were evaluated in comparison with commercial synthetic antioxidants. Total phenolic content of the perilla seed was 0.75% as chlorogenic acid. Each percent ratio of the content of free, ester, and insoluble bound phenolic acid to total phenolic content was 87.5, 7.5 and 5.0% respectively. Chlorogenic acid was identified as a major phenolic acid and a small amount of caffeic acid was also identified in the free phenolic acid extract, but they were not found in soluble ester and insoluble bound phenolic extracts by two dimensional paper chromatography. Each type phenolic extract from 30g of deffated perilla flour showed antioxidant activity similar to that of BHT (0.02%, w/w) in 200g of soybean oil substrate inspite of the difference of each phenolic content.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1045-1050
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• 1998

This study was carried out to investigate the oxidative stability of oils from peril1a seeds roasted at $190^{\circ}C$ for $0{\sim}50$ min. The oxidative stability of perilla oils increased as the roasting time increased. Oxidative stability of perilla oils extracted methanol extracts significantly decreased. When 1.0%(w/w) methanol and hexane fractions prepared from methanol extracts added to the unroasted perilla oils, methanol fractions showed strong antioxidative effects, but hexane fractions showed weak effects. As the roasting time increased, the browning intensity, fluorescence and electron donating ability of methanol extracts, methanol and hexane fractions increased, and those were closely related with antioxidative effects.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.560-565
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• 1993

This study was conducted to obtain basic information for breeding materials on the oil quality improvement of perilla seeds. Oil contents and omega(${\omega}$)fatty acid compositions of seeds were investigated to 317 varieties of domestic perillas. Oil contents of 317 perilla varieties ranged from 35.6 to 55.3 with 44.5% of varietal mean. The major omega fatty acids contained in the oil were oleic acid(${\omega}$-9) 15.2%, linoleic acid(${\omega}$-36) 13.9% and linolenic acid(${\omega}$-3) 63.1% in the mean value. Varietal variation of $\omega$-9, 6 and 3 fatty acids ranged of 9.5～21.4%, 9.1～20.4% and 50.6～70.5% respectively. Unsaturated fatty acid were averaged 92.2% of seed oil in fatty acid composition. The ratios of ${\omega}$-6 to ${\omega}$-3 ranged of 0.13～0.34%(0.22% in mean value). The highest linolenic acid variety was Yecheonjong being 70.5%. The lowest variety in rations of ${\omega}$-6 to ${\omega}$-3 was Goseongjong being 0.13%. Oil content showed positive correlation with stearic acid and linolenic acid, while the negative correlation with oil content and linoleic acid. On the other hand, A significant negative correlation were showed between lionolenic acid and the ratios ${\omega}$-6 / ${\omega}$-3 fatty acid, saturated fatty acid. Saturated fatty acid was highly correlated with unsaturated fatty acid negatively being r=-0.723$^{**}$

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.373-378
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• 1993

A rapid gas chromatographic profiling method for the simultaneous analysis of free fatty and other acids was applied to vegetable oils. Oil samples were dissolved in dichloromethane and the free acids were extracted with saturated $NaHCO_3$ solution. The aqueous extract was acidified and then loaded onto the Chromosorb P column for the extraction. The acids were eluted with diethyl ether selectively from Chromosorb P column and were treated with triethylamine to prevent the losses of volatile acids. Several long chain fatty acids were detected from soybean oil, rice-bran oil, sesame oil and perilla oil. Various organic acids including odd number fatty acids were detected in crude oil, especially sesame oil. Arachidic acid from perilla oil and vanillic acid from sesame oil, which were not reported before were detected. The content ratio of free linoleic acid to oleic acid was $1.02{\sim}1.18$, which was similar to the reported data. When the GC profile of organic acids were simplified to their corresponding retention index spectra of bar graphical forms, they presented characteristic pattern of each vegetable oil that can be quickly recognized.