• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.930-936
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• 2004

Effects of rice cultivars and degree of milling (DM) on composition, pasting properties, total phenolic contents, and distribution of phenolic acids were investigated. Rice and bran fractions with 94.4, 92.0, and 90.4% milling yields from brown rice of four cultivars (Odae, Nampyung, Chucheong, and Ilmi) were used. Fat and ash contents of milled rices decreased with increasing DM, whereas protein contents were not affected. In rice bran, differences in fat and ash contents by cultivars were higher than those caused by DM. With increasing DM, gelatinization temperature of rice flour decreased, whereas peak viscosity and hold viscosity at $95^{\circ}C$ increased. While cold viscosity, final viscosity, and setback varied among cultivars, DM had little effect. Total polyphenolic contents in brown rice, milled rice, and rice bran were 93.9-88.8, 30.3-71.9, and 310.0-541.6 mg catechin eq/100g, respectively. Major phenolic compounds were identified as ferulic and p-coumaric acids. Total phenolic content of brown rice (65.9-27.9 mg%) decreased with increasing DM, whereas ratio of ferulic acid composition increased. Chucheong and Ilmi varieties showed biggest reduction of phenolic acid contents by milling. In rice bran, ferulic and p-coumaric acids were 157.8-240.2 and 31.8-90.4 mg%, respectively. Contents of sinapinic, benzoic, and m-hydroxybenzoic acids in rice bran were higher than those of brown and milled rices.

• 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 Ginseng Research
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• v.30 no.1
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• pp.22-30
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• 2006

Phenolic acids of white ginseng were extracted and fractionated into free, esterified, and insoluble-bound forms. The contents of individual phenolic acids in different forms were quantified by gas liquid chromatography. Nine different phenolic acids as free, esterified, and insoluble-bound forms were identified in white ginseng. Total phenolic compounds in different forms of extracts was 0.309% (free form), 0.230% (esterified form) and 0.138% (insoluble-bound form), respectively. Total phenolic acid contents in free, esterified and insoluble-bound form were 889.3, 356.8, 1,176.9 mg/100g fraction, respectively. Ferulic acid was the predominant phenolic acid, representing 63.7% and 50.9% of total phenolic acids in esterified fom and insoluble-bound form, respectively. While caffeic acid was only detected in esterified form. At 10 mg/ml insoluble-bound form quenched 95.9% ABTS free radicals generated from 2,2-azobis(2-amidinopropane) dihydrochloride (AAPH). Also, electron donating ability and lipid peroxidation inhibitory activity of insoluble-bound fom were higher than other fraction. All phenolic acid fractions scavenged over 80% of hydroxyl radical at 10 mg/ml.

• Journal of Digital Convergence
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• v.19 no.4
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• pp.365-371
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• 2021

In order to verify the effect of using functional cosmetic ingredients for skin beauty, the composition and content of some phenolic acid and flavonoids in the hot water and 80% methanol extract of Akebia quinata fruit pericarp and seeds were analyzed, and the skin care antioxidant activity was investigated. The results are as follows. Total polyphenol and flavonoid contents were found to be higher in pericarp extract than seed extract in both hot water and 80% methanol extract. In the analysis of the composition and content of phenolic acid and flavonoids, two kinds of phenolic acids were identified in the hot water extract of pericarp, 6 kinds of phenolic acids were identified in the 80% methanol extract, and one kind of flavonoid. Two types of phenolic acids were identified in the hot water and 80% methanol extract of seeds, respectively. DPPH and ABTS radical scavenging activities tended to increase in proportion to the treatment concentration in both hot water and 80% methanol extracts, and antioxidant activity was found to be high. Therefore, from the above results, it was found that the hot water and 80% methanol extract of Akebia quinata fruit pericarp and seeds contained various kinds of phenolic acid and flavonoids, and the antioxidant activity was also high. It is believed to be of value as a natural antioxidant in skin care cosmetic ingredients.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.38-43
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• 1997

Free phenolic acids (FPA), soluble phenolic acid esters (SPA) and insoluble-bound phenolic acids (IPA) were extracted from defatted Perillae semen flour and the antioxidative components in FPA extract was separated by column chromatography and HPLC. Total phenolic content of defatted Perillae semen flour was 0.38% as chlorogenic acid and each percent ratio of the content of FPA, SPA and IPA to total phenolic content was 71.1%, 15.8% and 13.1%, respectively. The antioxidative activity was compared by measuring of electron donating ability (EDA) and thiobarbituric acid value (linoleic acid substrates). The FPA extract was showed the highest antioxidative activity among the three kinds of phenolic extracts. The FPA extract showing the highest antioxidative activity was separated by silica gel column chromatography and then the separated fractions were compared in terms of antioxidative activity. The fractions of acetone : methanol (8 : 2) showing the highest antioxidative activity was further separated by HPLC. Five fractions (F-I, F-II, F-III, F-IV and F-V) were observed on the HPLC chromatogram and F-I fraction showed the highest antioxidative activity.

• Journal of the Korean Society of Food Culture
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• v.14 no.1
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• pp.43-48
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• 1999

The antioxidative effects of phenolic acids extracts from defatted sesame meal were investigated on the soybean oil. The free, ester and insoluble bound phenolic acids in the extracts from defatted sesame meal were isolated and their antioxidative activities were evaluated with commercial synthetic antioxidants such as BHA, AP and TBHQ. The patterns of these extracts were compared by using gas chromatography. Ether extracts from the defatted sesame meal showed a higher antioxidative effectiveness than BHA and AP. Among phenolic extracts, free phenolic acid and soluble phenolic acid ester were found most effective in the sesame meal. Each phenolic extract was confirmed to be composed of six or three individual compounds.

• Korean Journal of Medicinal Crop Science
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• v.20 no.6
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• pp.447-453
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• 2012

This study was conducted to determine the contents of phenolic compounds and astragalosides in Astragalus membranaceus. Between the phenolic compound groups, flavonoids compounds (51.13%) had higher average concentrations than the phenolic acids groups. Among the 30 phenolic compounds, quercetin ($353.11{\mu}g\;g^{-1}$) provided the highest concentrations. According to different cultivation year, 3-year-cultivated Astragalus ($2612.57{\mu}g\;g^{-1}$) showed the highest concentrations of phenolic compounds. According to different harvest days, 6/5 harvesting Astragalus ($2615.80{\mu}g\;g^{-1}$) showed the highest concentrations of phenolic acids. Comparison between the top and subterranean parts of harvested Astragalus plants cultivated for 2 years, 3 years, and 5 years showed big difference of total phenolic compounds in concentrations. Further, the top part had higher amounts of the total phenolic compounds than the subterranean part among all Astragalus. This tendency was similar to those of the top root and lateral root. The concentration of the phenolic compounds in the top root was higher than that of the lateral root.

• Preventive Nutrition and Food Science
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• v.8 no.2
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• pp.200-218
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• 2003

Phenolic compounds in food and plant materials belong to the simple phenols, phenolic acids, coumarins, flavonoids, stilbenes, tannins, lignans and lignins, all of which are considered as secondary plant metabolites. These compounds may be synthesized by plants during normal development or in response to stress conditions. Phenolics are not distributed uniformly in plants. Insoluble phenolics are components of cell walls while soluble ones are present in vacuoles. A cursory account of phenolics of cereals, beans, pulses, fruits, vegetables and oilseeds is provided in this overview. The information on the bioavailability and absorption of plant phenolics remains fragmentary and diverse. Pharmacological potentials of food phenolics ave extensively evaluated. However, there are many challenges that must be overcome in order to fully understand both the function of phenolics in plant as well as their health effects.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.270-270
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• 2017

Brown rice flour (BRF) was treated with different carbohydrases (Viscozyme, Termamyl, Celluclast, AMG, Ultraflo, and Pentopan), and then aqueous alcoholic extracts (70% ethanol) from the treated RBF were examined for their phenolic compositions and antioxidant activities (ABTS and DPPH radical scavenging activity). All the carbohydrases tested induced significant increases in ABTS radical scavenging activity (2.1-3.0 times). Moreover, These enzymes increased the amount of extractable free phenolic acids by 10-15 times, especially for ferulic and p-coumaric acid. Among the enzymes tested, Pentopan which was active in arabinoxylan hydrolysis appeared to be most effective in increasing the free phenolic acid content and ABTS radical scavenging activity than other enzymes. Enzymatic hydrolysis of cell wall polysaccharides in BRF could be used as an effective procedure for raising the amount of extractable phenolic acids and thus increasing the antioxidant activity of BRF extract.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.824-827
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• 1990

Phenolic acids are widely distributed in all plant meterial. Most of these acids were combined with plant or grain cell wall. On the other hand, it had been reported that p-coumaric acid exhibited hypocholesterolemic activity in rats. We have undertaken a study of these compounds with regard to their effect on the rat. In this study, the effects of phenolic acid on the serum cholesterol level in rats fed with cholesterol free and cholesterol enriched diets were examined. The commercially available phenolic acid were purchased in the experiment. These compounds were incoporated in the diet at a level of 0.2%. These diets were fed for 21 days to male wistar strain rats with a body weight of 80 to 90g. It was found no significant change in serum cholesterol level in the phenolic acid fed rats in both cholesterol-free and cholesterol-enriched diet.