• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1403-1408
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• 2000

The methanol soluble fraction of the hot water extracts from Hovenia dulcis Thunb showed antioxidative and antimicrobial activity. The methanol fraction was successively purified with solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, and octadecylsilane column chromatography. The purified active substances were isolated by high performance liquid chromatography. The isolated substances were identified as 3-methoxy-4-hydroxybenzoic acid (vanillic acid) and 3-methoxy- 4-hydroxycinnamic acid (ferulic acid) by LC-MS and GC-MS. Vanillic acid and ferulic acid showed antimicrobial activity against Gram-positive bacteria, Gram-negative bacteria and yeast. The DPPH-radical scavenging activity of ferulic acid appeared more active than that of vanillic acid. DPPH-radical scavenging concentration of ferulic acid and vanillic acid were $14\;{\mu}g/mL\;(SC_{50})$, $100\;{\mu}g/mL\;(SC_{10})$, respectively.

• BMB Reports
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• v.34 no.4
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• pp.299-304
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• 2001

The 3-Deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) synthase is the first enzyme of aromatic amino acid-, folic acid-, and phenazine-1-carboxylic acid biosynthetic pathways. DAHP synthase of Bacillus sp. B-6 that produces phenazine-1-carboxylic acid was feedback inhibited by two intermediary metabolites of aromatic amino acid biosynthetic pathways, prephenate and chorismate, but not by other metabolites, such as anthranilic acid, shikimic acid, p-aminobenzoic acid, and 3-hydroxyanthranilic acid. DAHP synthase of Bacillus sp. B-6 was not inhibited by end products, such as aromatic amino acids, folic acid, and phenazine-1-carboxylic acid. The inhibition of DAHP synthase by prephenate and chorismate was non-competitive with respect to erythrose 4-phosphate and phosphoenolpyruvate. Prephenate and chorismate inhibited 50% of the DAHP synthase activity at concentrations of $2{\times}10^{-5}\;M$ and $1.2{\times}10^{-4}\;M$, respectively The synthesis of DAHP synthase of Bacillus sp. B-6 was not repressed by exogenous aromatic amino acids, folic acid, and phenazine 1-carboxylic acid, single or in combinations.

• Journal of the Korean Applied Science and Technology
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• v.11 no.2
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• pp.129-138
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• 1994

In order to investigate of the Influence of $Mg^{2+}$, $Ca^{2+}$ on ${\alpha}$-linolenic acid converted into the eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA) forming in plasma lipid and in liver microsomes of rabbit, the animals were fed on the perila oil rich ${\alpha}$-linolenic acid or sardine oil rich EPA and DBA diet for 4 weeks were examined. In plasma, liver lipid, $Mg^{2+}$ was influenced on arachidonic acid(AA), EPA, DHA formative from ${\alpha}$-linolenic acid in perilla oil, but stearic acid was increased, $Ca^{2+}$ was Influenced on stearic acid increased and DHA was decreased. In phospholipid, $Mg^{2+}$, $Ca^{2+}$ was influenced on stearic acid increased and DHA was decreased in perilla oil.

• Journal of Korean Society of Forest Science
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• v.103 no.1
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• pp.113-121
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• 2014

From the bark of Euonymus japonica, ten compounds were isolated by column chromatography and identified as follows. The structures were determined as : (-)-epicatechin, (-)-epigallocatechin, vanillic acid, 2,4-dimethoxyphenol-1-glucoside, 2, 4, 6-trimethoxyphenol-glucoside, 5-caffeoylquinic acid, 4-caffeoyuinic acid, 3, 4-dicaffeoylquinic acid, 3, 5-dicaffeoylquinic acid, and 1, 5-dicaffeoylquinic acid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.3
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• pp.156-160
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• 2005

We studied the effect of SMP (solid matrix priming) treatment, seed pretreatment for germination enhancement, to tobacco seeds by measurement of germination rate and contents of fatty acid, energy source for tobacco germination. The results were as follows. In result of germination test, germinative ability was the highest in KF109 at nine day treatment and in KB108 at seven day treatment. The composition of fatty acid in tobacco seed confirmed by gas chromatography were palmitic acid, stearic acid, oleic acid+elaidic acid, linoleic acid+linole­laidic acid, and $\alpha-linolenic$ acid. Palmitic acid, stearic acid, oleic acid and elaidic acid, and linoleic acid and linole-laidic acid were highest in KF109 at eight or nine day treatment and in KB108 at six or seven day treatment. Especially, content of oleic acid + elaidic acid, and linoleic acid+linolelaidic acid were changed largely by treatment, so these might be used for index to examine treatment effect.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.721-726
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• 1996

Fatty acid composition and phenolic acid content of rice with different milling fractions were analyzed to provide basic data for nutrition, processing and storage of rice. Major fatty acids of rice were palmitic, oleic and linoleic acids and their respective contents were 20.0%, 33.3% and 43.0% of embryo, 17.3%, 45.1% and 34.5% of rice bran and 23.4%, 26.2% and 46.1% of milled rice. Outer fraction had a high content of oleic acid but a low content of linoleic acid in rice bran. As milling yields increased in milled rice, oleic acid content increased, but palmitic acid, linoleic acid, stearic acid and linolenic acid contents decreased. Contents of free, esterified and insoluble bound phenolic acid extracts from bran were 321.0mg%, 299.7mg% and 212.4mg%, respectively. Milled rice contained 118.0mg% of free phenolic acids, 56.0mg% of insoluble bound phenolic acids and no esterified phenolic acids. Rice bran contained 86.2% of ferulic acid as a principal phenolic acid. It also contained 35.7~36.6% of sinapic and syringic acids, 16.7% of p-coumaric acid and 0.13% of vanillic acid as minor component. Contents of total phenolic acid, expressed in terms of tannic acid, among rice with different milling fractions was highest in embryo. It was higher in outer fraction in bran, but rarely detected as fractionation of the component with milling in milled rice.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.8-15
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• 1986

This study was carried out to investigate changes of the lipid contents and the fatty acid composition in shank during heating time and frozen storage. 1. The total lipid contents of raw shank were about 3.57% and decreased stepwise during heating time 30, 60, 90 min and frozen storage(24hrs) The contents of neutral lipid, glycolipid and phospholipid were 70.71%, 6.36%, and 22.93% in raw shank, and neutral lipid contents were decreased, whereas Phospholipid contents were increased according to heating tide. In frozen storage, neutral lipid and glycolipid contents were increased, while phospholipid contents were decreased. 2. Lipids of shank possessed about 8 kinds of fatty acid as the constituent by gas-liquid chromatography analysis. The main fatty acids were oleic acid, palmitic acistearic acid and linoleic acid: the fatty acids of total lipids in raw shank were 43.48% of oleic acid, 23.13% of palmitic acid,12.00% of stearic acid and 6.75% of linoleic acid. Also the fatty acids were 43.32% of oleic acid, 23.26% of palmitic acid, 9.30% of stearic acid 2.15% of linoleic acid in neutral lipid, 22.63% of oleic acid, 8.44% of palmitic acid, 11.98% of stearic acid, 27.01% of linoleic acidin glycolipid, 39.38% of oleic acid, 15.89% of palmitic acid, 15.55% of stearic acid, 17.49% of linoleic acid in phospholipid. 3. The fatty acid pattern of total lipid, neutral lipid, glycolipid and phospholipid was not any changes, whereas there was a difference in the fatty acid contents: palmitic acid and stearic acid of total lipid were decreased in the 30 min and 60 min heating but increased in 90min heating, and linoleic acid of neutral lipid was increased stepwise during heating time and frozen storage. Also palmiict acid of glycolipid was increased gradually and linoleic acid in heating time 30, 60 min was higher than 90 min and frozen storage. Among fatty acids in phoapholipid, oleic acid was increased during heating time, while decreased in frozen storage, and linoleic acid was not any change but linolanic acid was increased. UFA/SFA of phospholipid was the highest when heating time was 60 min. From above results, it was found that when heating time was 60 min beneficial nutritionally, comparing with changes of fatty acid composition according to the heating time aid frozen storage.

• The Korean Journal of Zoology
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• v.8 no.2
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• pp.15-18
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• 1965

Fatty acid components of the Chestnut gall wasp (Dryocosmus kuriphilus YASUMATSU) were analyzed by the method of gas chromatogrphy at various developmental stages. 1. The fatty acids identified at each stage are as follows : Larva stage : acetic acid , benzoic acid and capric acid. Prepupa stage : acetic acid, benzoic acid and capric acid. Pupa stage : acetic acid, benzoic acid and capric acid. 2. Through the development of the wasp, there were large amount of acetic acid.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.120-125
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• 1981

Organic acids of Kochuzang (red pepper paste) prepared from glutinous rice, polished barley, wheat flour and sweet potato were analyzed by a gas chromatography. Lactic, pyruvic, succinic, fumaric, malic, pyroglutamic and citric acid were identified. And trace amount of oxalic acid was found in the Kochuzang prepared from sweet potato. The dominant organic acid of all samples was pyroglutamic acid, followed by pyruvic and citric acid. The organic acids were lower in Kochuzang from wheat flour than in other samples. The contents of succinic and fumaric acid were highest in Kochuzang prepared from sweet potato and were lowest in polished barley Kochuzang.

• Journal of the Korean institute of surface engineering
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• v.49 no.3
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• pp.231-237
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• 2016

This article reports a new chemical bath for preparing a mirror-like surface of AZ31 Mg alloy. In order to find an appropriate chemical polishing solution, four different acidic solutions of sulphuric acid, nitric acid, acetic acid and a specially designed mixture of nitric acid and acetic acid were investigated in view of the changes in surface appearance, roughness and dissolution rate of AZ31 Mg alloy. The surface scales on AZ31 Mg alloy were readily removed by all the acidic solutions, but a reflective surface was produced only by etching in the specially designed solution, and only after a specific etching time. The surface roughness increased with etching time in sulphuric acid, nitric acid, and acetic acid, but it lowered after a specific etching time in the specially designed mixture of nitric acid and acetic acid. Dissolution rate of the alloy in the specially designed mixture of nitric acid and acetic acid appeared to be more than twice than that in separate nitric acid or acetic acid. In this work, we recommend the mirror-like surface of AZ31 Mg alloy obtained by polishing for an optimum time in a mixture of nitric acid and acetic acid for following surface finishings, chemical conversion coating, electroplating, electrophoretic painting and anodizing treatment.