• Preventive Nutrition and Food Science
• /
• v.11 no.4
• /
• pp.278-284
• /
• 2006

The beneficial effects of digested onion extracts have been assessed by antimutagenic and anticancer activities by Ames test and SRB test. The total phenolic acids and flavonoids in onion extracts were determined. Red and yellow onions contain more phenolic acids and flavonoids than those in the white onion. Digested, extracts showed antimutagenic activity and anticancer activity, and it appears that the antimutagenic activity of digested extracts of onion against mutagens and anticancer activities were related to their phenols and flavonoids contents. Moreover, the extracts inhibited the proliferation of four human tumorigenic cell lines such as HT-29 (colon), MCF-7 (breast), DU-145 (prostate) and HepG2 (liver), in a dose-dependent manner. Phenolic acids and flavonoids caused oxidative damage to the cancer cell lines and induced apoptosis. Generally, red onion extracts showed effective antimutagenic and anticancer activity, and the digested red onion extracts elicited stronger antimutagenic activity than those of the onion extracts without digestion.

• Composites Research
• /
• v.17 no.3
• /
• pp.52-61
• /
• 2004

"Phenolic composites", one of safety composites, was also chosen to build boats in England. One of the authors, Mr. Forsdyke and his researcher, Dr. Orpin describe how phenolic composites were chosen as construction material for marine application. The reader can get very good understandings from design point of view through this paper.his paper.

• Korean Journal of Pharmacognosy
• /
• v.43 no.3
• /
• pp.213-216
• /
• 2012

Six phenolic compounds were isolated from the aerial parts of Bromus japonicus (Gramineae) through repeated column chromatography. Their chemical structures were elucidated as luteolin (1), caffeic acid (2), luteolin-7-O-${\beta}$-D-glucopyranoside (3), quercetin-3-O-${\beta}$-D-galactopyranoside (4), quercetin-3-O-${\beta}$-D-glucopyranoside (5), and luteolin-4'-O-${\beta}$-D-glucopyranoside (6), respectively, by spectroscopic analysis. These compounds were isolated for the first time from this plant.

• Natural Product Sciences
• /
• v.19 no.1
• /
• pp.8-14
• /
• 2013

The inhibitory effect and the structure-activity relationships of luteolin and its related derivatives isolated from Taraxacum mongolicum against MAO activities were investigated. The activity-guided isolation of extract from Taraxacum mongolicum led to the isolation of three flavonoids, luteolin, diosmetin, and luteolin-7-glucoside, a polyphenol, chlorogenic acid, a tyrosine and a uridine. The inhibitory activities of luteolin and its related derivatives against MAOs activities are dependent on their molecular structures. The presence of the phenolic hydroxy group at para-position is the active site for MAO-A inhibition as well as of MAO-B. The methoxy group has no potential on MAO-A inhibition. An additional phenolic hydroxy group at the ortho-position alleviates about 4-fold MAO-A inhibitory activity of phenolic hydroxy group at para-position. A carboxylic group seems to be critical for DBH inhibition and has no effects on MAO.

• Natural Product Sciences
• /
• v.2 no.1
• /
• pp.14-18
• /
• 1996

A new phenolic glycoside named mussaendoside L (1), along with four known iridoidal glycosides $(2{\sim}5)$ were isolated from the aerial parts of Mussaenda pubescens Ait.f. Their structures were elucidated on the basis of chemical and spectroscopic evidence.

• Korean Journal of Pharmacognosy
• /
• v.46 no.4
• /
• pp.303-308
• /
• 2015

Ten phenolic compounds were isolated from the twigs of Stewartia pseudocamellia. The isolated compounds were identified as 5,7,3',5'-tetrahydroxyflavanone (1), 3,5,7,3',5'-pentahydroxyflavanone (2), quercetin (3), (+)-aromadendrin (4), (+)-ampelopsin (5), myricetin (6), (+)-catechin (7), (-)-epicatechin (8), kaempferol (9), and fraxin (10) by spectroscopic analysis. Compounds 1, 2, 4, 6, 8, and 9 were isolated from this plant for the first time. The antioxidant activities of compounds 1-10 were evaluated by the DPPH and/or ORAC (oxygen radical absorbance capacity) assay. Compounds 3, 5-9 showed significant antioxidative effects on DPPH assay. Among the active compounds, 6 exhibited higher activity compared to trolox on ORAC assay.

• Korean Journal of Pharmacognosy
• /
• v.39 no.1
• /
• pp.28-36
• /
• 2008

From the 70% EtOH extract of Paeonia lactiflora roots (Paeoniaceae), fourteen phenolic and related compounds were isolated. They were identified as ${\alpha}-tocopherol$ (1), dioctylphthalate (2), ${\alpha}-tocospiro$ B (3), paeonol (4), 3,3'-di-O-methylellagic acid(5), 3,4'-di-O-methylellagic acid (6), benzoic acid (7), aromadendrin (8), p-hydroxybenzoic acid (9), (+)-catechin (10), gallic acid (11), nicotinamide (12), methyl gallate (13) and $1,2,3,4,6-penta-O-galloyl-{\beta}-D-glucose$ (14) by spectroscopic methods. Among these compounds, 1-3, 5, 6, 8 and 12 were isolated for the first time from this plant.

• Tribology and Lubricants
• /
• v.15 no.4
• /
• pp.314-320
• /
• 1999

Friction and wear characteristics of phenolic resin-based friction materials reinforced with aramid pulp and potassium titanate were investigated using a pad-on-disk type friction tester. Friction characteristics such as friction stability, thermal stability, and wear rate varied according to the type of phenolic resins and the relative amount of aramid pulp and potassium titanate. The modified novolac resin-based friction materials showed better heat resistance and friction stability than those with the unmodified(straight) novolac resin. Compared with friction materials filled with potassium titanate or aramid pulp only, the friction materials reinforced with both aramid pulp and potassium titanate showed good friction stability and wear resistance. Increment of aramid pulp from 10 to 20 vol.% however, showed little difference in friction stability.

• Korean journal of food and cookery science
• /
• v.23 no.1 s.97
• /
• pp.19-24
• /
• 2007

This study investigated the antioxidant and synergistic effects and nitrite scavenging ability of some phenolic compounds(catechin, rutin, quercetin and naringin), The electron donating abilities of naringin, quercetin, rutin and catechin were 6.7%, 92.8%, 87.6% and 92.21%, respectively, The antioxidant activities in O/W emulsion substrates were in order of rutin > quercetin > catechin > naringin. The antioxidant effect of rutin was stranger than that of BHT or ${\alpha}$-tocopherol. ${\alpha}$-tocopherol showed synergistic effect with catechin and quercetin, but ascorbic acid not showed effect. The nitrite scavenging abilities of catechin, quercetin, rutin and naringin were 99.9%, 98.6%, 25.5% and 0.2%, respectively. The nitrite scavenging abilities of quercetin and actechin were very potent as compared with those of BHT and ascorbic acid.

• Preventive Nutrition and Food Science
• /
• v.21 no.3
• /
• pp.263-270
• /
• 2016

This study investigated the phenolic, flavonoid, and vitamin constituents in the main root, root hair, and leaf of ginseng. The total individual phenolic and flavonoid contents were the highest in the leaf, followed by the main root and root hair. Ferulic acid and m-coumaric acid were found to be the major phenolics in the main root and root hair, while p-coumaric acid and m-coumaric acid were the major phenolics in the leaf. Catechin was the major flavonoid component in the main root and root hair, while catechin and kaempferol were the major flavonoid components in the leaf. Pantothenic acid was detected in the highest quantity in the non-leaf parts of ginseng, followed by thiamine and cobalamin. Linolenic acid and menadione were the major components in all parts of ginseng.