• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.593-597
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• 2010

This study investigated the properties and antioxidative activities of phenolic acid concentrates of rice bran. Rice bran contains bioactive substances such as phenolic compounds, which can provide health benefits as natural antioxidants. This study examined how levels of phenolic acids can be obtained efficiently through various extraction methods. The extractions of defatted rice bran were followed by using ethylacetate (RBE-I), ethylacetate after alkaline hydrolysis (RBE-II), and 80% methanol (RBE-III). For all extracts, yields (%), total polyphenol contents (TPC), various phenolic acids and antioxidative activities were estimated. RBE-II had the highest total polyphenol contents (526.72 mg/100 g rice bran) and showed high antioxidative activity (74.7%). To concentrate the phenolic acids, RBE-II was passed through Sep-pak $C_{18}$ Vac cartridge and F1-RBE-II was collected by the elution of 50% methanol. The total phenolic content of F1-RBE-II (736.8 mg/100 g rice bran) was higher than that of RBE-II (367.1 mg/100 g rice bran), and the ratios of ferulic acid (73%) and sinapic acid (14%) increased. As RBE-II was analysed by HPLC, 6 different phenolic acids were found via chromatography, whereas F1-RBE-II showed 5 different peaks and the major phenolic acid was identified as ferulic acid. The ABTS radical scavenging activity of F1-RBE-II was the highest among the rice bran extracts. In a ${\beta}$-carotene-linoleic acid model system, linoleic acid oxidation was reduced by F1-RBE-II (73%) and RBE-II (35%).

• Journal of Life Science
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• v.25 no.9
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• pp.1014-1020
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• 2015

This study suggests that fermented rice bran extract contains natural antioxidants. The contents of bioactive materials (e.g., polyphenolic compounds and flavonoids), antioxidative properties (DPPH (α,α'- diphenyl-β-picrylhydrazyl) free radical scavenging activity, Fe reducing, Cu reducing power, peroxidation of linoleic acid and rat hepatocyte microsome) were tested by in vitro experimental models using fermented rice bran (FRB) extract. The concentrations of phenolic compound and flavonoid were 19.92 mg/g and 11.56 mg/g, respectively. In oxidation in vitro models using DPPH free radical scavenging activity, (free radical scavenging activity 69.8%) Fe reducing power and Cu reducing power (effect of dose-dependent manner), Fe²⁺/ascorbate induced linolenic acid peroxidation by ferric thiocyanate and thiobarbituric acid (TBA) methods (inhibition activity 81%), and autooxidation of rat hepatic microsomes membrane (lipid peroxidation inhibition activity 38%), antioxidative activities were stronger in FRB extract than FRS (Fermented Rice and Soybean, positive control) extract and, these effects were dose-dependent manner. From these results, FRB extract was shown to have the most potent antioxidative properties and contain the highest amounts of antioxidative compounds such as phenolic compounds and flavonoids. Overall, these results may provide the basic data to understand the antioxidative properties of fermented rice bran for development of functional foods.

• The Korean Journal of Community Living Science
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• v.23 no.3
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• pp.245-254
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• 2012

This study was performed to determine the component analysis and measurements of antioxidant activities from natural seasoning containing Lentinus edodes powder (NSLP) in order to detect the biological activities and develop novel functional resources. It was extracted with 70% ethanol and then further fractionated to hexane, chloroform, ethyl acetate, butanol and water. Methods used in this experiment were measured to examine total polyphenol contents and total flavonoid contents, reducing power and Superoxide dismutase-like activity. Composition analysis were highly composed of carbohydrate as 44.1%. The minerals of different organics were highly composed of sodium as 5,073 mg/100g. There were seventeen total amino acids in NSLP. The glutamic acid content was high up to 16.9 mg/g and aspartic acid, lysine, leucine, alanine were followed. Predominant fatty acid was linoleic acid (62.7%) in NSLP. Contents of total polyphenols in butanol fraction from NSLP were 16.38 mg/100mL. While overall butanol fraction have higher reducing power than ethanol extract, after the addition of 400 ${\mu}g/mL$ butanol fraction, auto oxidation of pyrogallol decreased to 83.62% as a result of superoxide dismutase-like activity. A positive correlation was observed between total polyphenol, flavonoid and antioxidant activities.

• The Korean Journal of Food And Nutrition
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• v.15 no.4
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• pp.342-349
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• 2002

Rapeseed oil is easily oxidized due to the high contents of unsaturated fatty acid such as linoleic acid and linolenic acid. For stability of rapeseed oil oxidation, a special process is required. Two kind of simple and interesterifying mixed rapeseed oil were prepared according to add 30%, 50% and 70% of coconut oil and palm oil. Sample oils were heated at 180${\pm}$5$^{\circ}C$ for 5, 10, 15, 20, 25, 30 and 35 hours. Then the physicochemical properties such as the tendency of oxidation were investigated. The initial AV and POV of interesterifying mixed rapeseed oil were higher than those of simple mixed oil. But the tendency of oxidation were similar. While oxidation rate of similar and interesterifying mixed rapeseed oils with coconut oil and palm oil were lower about than those of rapeseed oil.

• Journal of Animal Science and Technology
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• v.48 no.6
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• pp.827-838
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• 2006

This experiment was carried out to investigate the effects of dietary vitamin E levels on carcass characteristics and vitamin E contents, fatty acid composition and lipid oxidation as indicated by thiobarbituric acid reactive substances(TBARS) of the longissimus muscle in Hanwoo steers. Forty Hanwoo steers were randomly assigned to one of four groups and fed the diet containing 200(control), 1000, 2000 or 2500 IU a(alpha)-tocopherol acetate/head/day for 3 months of last finishing period. Backfat thickness was thinner and beef fat color was whiter(P<0.05) in steers fed the vitamin E supplemented diets than those fed the control diet. But the longissimus muscle area and yield grade did not differ among treatments. Marbling score and quality grade were higher(P<0.05) in steers fed the diets containing 1000 and 2000 IU vitamin E than those fed the other diets. Vitamin E concentration in the longissimus muscle was higher(P<0.05) as the vitamin E content in diet was higher. The levels of oleic and linoleic acids in the longissimus muscle were not affected by dietary vitamin E levels. But linolenic and arachidonic acids were lower in steers fed the vitamin E supplemented diets than those fed the control diet. TBARS in the longissimus muscle was not affected by the vitamin E levels in diet until 5th day of storage but delayed muscle lipid oxidation in steers fed the vitamin E supplemented diets after 7th day of storage. Therefore according to this result, it may be concluded that steers have a higher quality grade and higher vitamin E concentration in muscle and lower in TBARS when diet contains 1000 or 2000 IU vitamin E per kg of diet.

• Journal of the Korean Home Economics Association
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• v.33 no.6
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• pp.245-253
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• 1995

The purpose of this study was to investigate the fatty acid composition and the rancidity of commercial deep-fat fried foods in Kangreung. the 7 kinds of samples were purchased form snack corners in 3 markets at AM 10 and PM 6 o'clock. The acid value, peroxide value and TBA value of the deep-fat fried foods were determined and the fatty acid composition were analyzed. The range of acid value was 0.45∼1.79, that of peroxide value was 1.24∼8.64meq/㎏,and that of TBA value was 12∼140 in all samples. There was significant difference in most of all samples by purchasing time and kinds of samples. But there was not specific tendency by purchasing times in each sample. Most of the acid value, peroxide value and TBA value of the samples fried with meats or sea foods showed higher value than the that of samples fried with vegetables or seaweeds. The fatty acid composition of the total lipids in the deep-fat fried foods were similar to one another. The major fatty acids were linoleic acid(C18 : 2) , oleic acid(C18 : 1) in order of content. Minor fatty acids were palmitic acid(C16 :0), linolenic acid(C18 : 3), stearic acid (C18 : 0) in order of content. the P/S ratio was the range of 2.12/1∼4.71/1 and the that of the samples fried with meats was the highest among samples. so there was the same tendency in this result between the chemical properties(acid value, peroxide value, TBA Value) and fatty acid composition. As a result of acid value and peroxide value in this study, the commercial deep-fat fried foods in Kangreung was safety.

• Journal of the Korean Professional Engineers Association
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• v.34 no.5
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• pp.82-88
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• 2001

Mackerel(Scomber japonicus), pacific saury (Cololabis saira) and sardine(Sardinops melanosticta) is widely distributed in coastal seawater of Korea, these fishes are not effective utilization as processing material cause by rapid lipid oxidation and off flavour. This study was attempted to lipid distribution in body section, whole body, meat, viscera, skin and head, and fatty acid composition of the oils obtained from these body section. The content of total lipid of mackerel, pacific saury and sardine were 12.48%, 12.79% and 13.81% respectively, and lipid contents in different body section of mackerel was muscle 2.31%, viscera 3.54%, skin 1.43% and head 5.20%, while in cause of sardine was muscle 4.17%, viscera 3.15%, skin 1.72%, and head4.77%. The major saturated fatty acids of mackerel, pacific saury and sardine oil were C$\_$16:0/(palmitic acid), C$\_$18:0/(stearic acid), C$\_$14:0/(myristic acid), and monoenoic acids was C$\_$18:0/(oleic acid), C$\_$16:1/ (palmitolic acid), C$\_$22:0/(erucic acid) and C$\_$20:1/(gadoleic acid), in cause of polyenoic acid was C$\_$22:6/(DHA, docosahexaenoic acid), C$\_$20:0/(EPA, eicosapentaenoic acid), C$\_$22:4/(behenic acid), C$\_$18:2/(linoleic acid) high quantity in order. When fresh oil extracted from mackerel, pacific saury and sardine was stored for 20 days at 5$\^{C}$, carbonyl and acid value of oil increased with storage day, but peroxide value decreased after 15 days.

• Journal of Life Science
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• v.28 no.5
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• pp.540-546
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• 2018

Annona muricata, generally known as soursop, graviola, or sirsak, is native to the warmest tropical areas of North and South America and is now widely distributed throughout tropical and subtropical parts of the world, including India and Nigeria. This study tested the contents of polyphenolic compounds, flavonoids, and minerals, as well as the antioxidative effects of DPPH radical-scavenging activity, Fe/Cu-reducing power, linoleic-acid peroxidation using thiobarbituric-acid (TBA) methods and peroxidation of rat-hepatocyte microsomes, and ${\beta}$-carotene bleaching assay. These were tested with in-vitro experimental models using water, ethanol, and methanol extracts of the Annona muricata leaf (AMl). Water extracts of AMl showed the highest extraction yield (1.76%). The total polyphenol-compound concentration was the highest in the methanol extract of AMl. However, the flavonoids concentration was the highest in the ethanol extracts of AMl. AMlMl major minerals were Ca, K, and Mg. In DPPH radical-scavenging activity, the contents exhibited a strong scavenging effect on the ethanol and methanol extracts of AMl. Additionally, the Fe/Cu-reducing power was strong in ethanol and methanol extracts of AMl. $Fe^{2+}$/ascorbate-induced linoleic-acid peroxidation using TBA methods and auto-oxidation of rat-hepatic microsomes showed strong antioxidative activities in ethanol extracts of AMl. ${\beta}$-Carotene bleaching was also highest in the ethanol extracts of AMl. These results may provide the basic data to understand the chemical characteristics and antioxidative effects of Annona muricata leaf extract for the development of functional foods.

• Clinical and Experimental Pediatrics
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• v.45 no.9
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• pp.1075-1082
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• 2002

Purpose : Obesity is known to be associated with hypertension, dyslipidemia, and fatty liver and is thought to be associated with increased levels of free fatty acids. One of the strategies for decreasing free fatty acid levels is stimulation of hepatic lipid oxidation with L-carnitine. Carnitine is an essential cofactor for transport of long-chain fatty acid into mitochondria for oxidation. This study was designed to evaluate the changes of serum fatty acids and carnitine levels after exogenous injection of L-carnitine. Methods : Sprague Dawley rats were divided into two groups. Group A was control. Group B was given intraperitoneal injection with L-carnitine(200 mg/kg) daily for two weeks. Serum lipid (total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol) and fatty acid levels were analyzed on the first day of the first and second weeks after injection of L-carnitine. Total, free, and acyl carnitine levels also were performed by a enzymatic cycling techniques at the same day intervals. Results : There was no significant difference between the two groups in total cholesterol, HDL-cholesterol, LDL-cholesterol levels before and after the administration of L-carnitine. But triglyceride levels were significantly decreased at the first week in group B compared with group A. Among free fatty acids, linoleic acid showed significant decrement(A group : $131.3{\pm}31.3mg/dL$ vs B group : $90.0{\pm}7.0mg/dL$) at the first week. Total, free, and acyl carnitine levels showed significant increments at all days intervals, but only free carnitine showed significant increments according to cumulative doses of carnitine. Conclusion : Plasma linoleic acid, a long-chain fatty acid, showed significant decrement after administration of L-carnitine in the first week. This may suggest that L-carnitine can be used as an antilipidemic agent for obese patients. A prospective study will investigate obese children in the future.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.67-76
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• 1990

To observe the propability as the frying oil and oxidative stability of red pepper seed oil, some physico-chemical tests of the oil were examined during 21 days storage period at 5$^{\circ}C$, 15$^{\circ}C$ and 30$^{\circ}C$, and AOM value determined and after heating the oil at 180${\pm}$5$^{\circ}C$ for 40 hours with or without antioxidants. The analysis storage stability of red pepper seed oil showed that the quality of storage group at 5$^{\circ}C$ was almost as good as fresh oil, and the storage group at 30$^{\circ}C$ showed certain degree of rancidity. Change of physico-chemical characteristic during storage were so small so that storage stability of red pepper seed oil was found to be good. AOM stability of red pepper seed oil was 7 hours which is lower than other vegetable oil, but the degree of stability grew greatly after adding phenolic antioxidants, such on TBHQ or PG. As for the chemical change after heating continuously for 40 hours, acid value, peroxide value and refractive index increased, but iodine value decreased as the heating processed. The fatty acid composition also showed the remarkable reduction of linoleic acid. The addition of antioxidants resulted in the delay of oxidation, the degree of which was greater in TBHQ than in PG.