• The Korean Journal of Ecology
• /
• v.24 no.3
• /
• pp.125-130
• /
• 2001

The allelopathic effects of aqueous extracts from Trifolium repens were studied. Aqueous extracts of leaves, stems, roots and flowers of T. repens strongly inhibited the seed germination and seedling growth of Zoysia japonica. In general, the higher concentration of the extracts showed the more great inhibition effect. The phenolic compounds extracted from T repens were analysed and identified using gas chromatography. 14 phenolic compounds were isolated from the leaves, stems, roots and flowers: caffeic acid, p-hydroxy benzoic acid, ferulic acid, gallic acid, p-coumaric acid, vanillic acid, trans-cinnamic acid, 2,5 dihydroxy benzoic acid, syringic acid, 2-hydroxy cinnamic acid, benzoic acid, salicylic acid, phloroglucinol and phanylacetic acid. The seed germination and relative growth ratio of Z. japonica by 14 phenolic compounds were inhibited in whole treatment. Stronger growth inhibitor were benzoic acid, salicylic acid and trans-cinnamic acid. From these results it is suggested that the phenolic compounds from T. repens seemed to be responsible for the allelopathic potential.

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

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

• Journal of Applied Biological Chemistry
• /
• v.57 no.1
• /
• pp.89-93
• /
• 2014

We aim to develop a simple method for simultaneous and quantitative determination of benzoic acid, caffeic acid and chlorogenic acid in seeds of Eriobotrya japonica. In addition, antibacterial effect of these three phenolic acids was examined. A basic method is performed on the high performance liquid chromatography system coupled to an UV-detector (230 nm) and reverse phase C-18 column ($4.6{\times}150mm$, $5{\mu}m$). Each phenolic acid was confirmed via liquid chromatography-mass spectrometry (MS)/MS system under the multiple-reaction monitoring with negative-ion electrospray ionization (ESI(-)) mode. It is demonstrated that the method was could be applied to samples for an analytical study of the phenolic acids. On the other hand, three phenolic acids in seeds of E. japonica exhibited antibacterial effect against several pathogenic bacteria. Of these, benzoic acid was found to have stronger antibacterial effect.

• Korean Journal of Microbiology
• /
• v.24 no.2
• /
• pp.168-174
• /
• 1986

The phenolic compounds contained in milled barley grains were seperated and identified by gas liquid chromatography and the effects of phenolic compounds extracted from milled barley grains and each authentic phenolic compound on the growth of Saccharomyces cerevisiae were studied. Severn phenolic acids, namely cinnamic, protocatechuic, ferulic, sinapid, vanillic, syringic, gallic acids, were identified in milled barley grains by gas liquid chromatography. The contents of sinapic, ferulic, cinnamic, protocatechuic acids were larger than those of vanillic and gallic acids. Phenolic compounds, extracted from milled barley grains and supplemented in culture broth, were inhibitory to the growth of Saccharomyces cerevisiae at levels above 100ppm to 24 hours but not inhibitory at all levels after 48 hours. Cinnamic, ferulic, vanillic acids at all levels were inhibitory to the growth of Saccharomyces cerevisiae, among them cinnamic acid was most inhibitory. Syringic acid was inhibitory to the growth of the yeast at the initial stage of culture. But sinapic and protocatechuic acids were slightly stimulatory to the growth of the yeast and gallic acid was ineffective to the growth of the yeast.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.3
• /
• pp.383-389
• /
• 1997

Doenjang(fermented soybean paste) was prepared by the series of processes including soaking, cooking, first fermentation(3 days at 30$\pm$2$^{\circ}C$) for the preparation of meju(soybean koji) after inoclulation of Aspergillus oryzae, and further fermentation (60 days at 30$\pm$2$^{\circ}C$) for the ripening after addition of salt 13% to meju. the crude phenolics extracted from defatted soybean and doenjang were fractionated onto the neutral phenolics(isofavonoids) and acidic phenolics(phenolic acids), respectively. Composition and antioxidative characteristics of phenolic fractions were determined. The neutral phenolic fractions contained genistin, genistein and daidzein; on the other hand, acidic phenolic fractions had syringic acid and seven other components. The content of genistin in doenjang dramatically decreased at the early stage of fermentation, whereas the content of genistein rather increased. In addition, the content of syringic acid of acidic phenolic fractions were increased during fermentation. These changes in individual phenolic components affected the antioxidative activity of neutral phenolics or acidic phenolics. antioxidative activity of phenolic compounds were evaluated during soybean fermentation. The antioxidative and free radical scavenging activity of neutral phenolic fractions and acidic phenolic fractions on linoleic acid autoxidation were also investigated.

• Journal of Ginseng Research
• /
• v.20 no.3
• /
• pp.284-290
• /
• 1996

To Identify phenolic components known to exist in Korean ginseng (Panax ginseng C.A. Meyer) by GC/MS, three derivatization methods were employed for their analyses. First, phenolic components in ether soluble acidic fraction prepared from Korean red ginseng powder were taimethylsilylated. Secondly, phenolic acids in the same fraction were esterified with diazomethane followed by trlmethylsilylation. Thirdly, acidic components in ginseng powder were extracted and esterified concurrently by methanolic sulfuric acid, followed by fractionation of phenolic components with Silica Sep-Paka and trimethylsilylatlon. All phenolic components found in ginseng except gen tisic acid were identified by retention times and mass spectrums of standards. Besides, 5 phenolic components including salicyl alcohol and 1-H-indole-2-carboxylic acid were first identified from Korea an red ginseng by GC/MS.

• The Korean Journal of Food And Nutrition
• /
• v.36 no.6
• /
• pp.506-514
• /
• 2023

Reported positive ion fragmentation of phenolic acid derivatives in rice (Oryza sativa L.) were summarized based on the literature. A total of eight phenolic acids (4 derivatives of ferulic acid, 3 derivatives of sinapic acid and p-coumaric acid) were isolated and identified from rice (raw and steamed) using UPLC-DAD-QToF/MS. Results revealed that 6-O-feruloylsurose was the major component with 3'-O-sinapoylsucorse being tentatively identified in Oryza sativa L. for the first time as a new hydroxycinnamoyl derivative in rice grains. In our study, raw brown rice had the highest phenolic acid contents with Samkwang showing higher phenolic acid content than Saeilmi and Sindongjin (12.41 vs. 7.89 and 3.10 mg/100 g dry weight, respectively). Of all varieties, brown rice had higher phenolic acid contents than white rice. These contents decreased considerably when rice was steamed whereas, p-coumaric acid and ferulic acid contents were increased. Additionally, contents of rice (raw and steamed) can be used as a fundamental report for new rice varieties.

• Journal of Ginseng Research
• /
• v.31 no.4
• /
• pp.230-236
• /
• 2007

This study was conducted to investigate the contents of the total phenolic compounds, and DPPH, ABTS radical scavenging activities of phenolic acid fractions of ginseng according to steaming times. Also the individual phenolic acid compositions and contents were analyzed by GC. The contents of the total phenolic compounds proportionally increased from 0.530 to 2.893% according to steaming times. Phenolic acid fractions were separated according to bound types, and the insoluble bound form fraction showed the highest contents followed by ester form fraction and free form fraction. The total contents of these three fractions (1.031-1.416%) were not significantly influenced by steaming times. Salicylic, cinamic, p-hydroxybenzoic, gentisic, vanillic, syringic, caffeic, ferolic acid were found in each fraction, and gentisic and ferolic acid were the major phenolic acid. Each phenolic acid fraction showed over 50% of DPPH and ABTS radical scavenging activities. There were no differences between the phenolic acid fractions according to binding types. Free radical scavenging activities were affected by a number of steaming times and augmented as steaming times increased.

• Journal of Food Hygiene and Safety
• /
• v.7 no.2
• /
• pp.107.1-112
• /
• 1992

Free-, soluble- and insoluble phenolic acids were extracted from defatted Galla Rhois. The extracts were then dissolved in equal amounts of an soybean oil, and POV (peroxide value) of the resulting substrates, portion of the soybean oil (control) and 0.02% BHT were measured by AOM (active oxygen method) test at 97.8$^{\circ}C$ for 40 hours through Rancimat method. Induction period of control, BHT, free phenolic acids, soluble phenolic acids and insoluble phenolic acids by the Rancimat method were 4.8, 10.5, 23.9 and 30.5hr. The phenolic acids separated and tentati-vely identified by gas chromatography were catechol, gallic acid, vanillin, protocatechuic acid, syri-ngic acid, ferulic acid.