• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.173-177
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• 1997

For the utilizing of tannins in the functional foods and natural inhibitor against browning reaction by tyrosinase in foods, inhibition effect against tyrosinase of tannins from Korean green tea was determined. Acetone extract from Korean green tea showed inhibition effect against tyrosinase. The gallocatechin compounds showed higher inhibition effect than the catechin compounds. In terms of stereo isomers, (-)-epicatechin compounds had higher inhibition effect than the (+)-catechin compounds. The monomer had higher inhibition effect than the dimer.

• Food Science and Preservation
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• v.9 no.4
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• pp.369-374
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• 2002

This study was performed to investigate the effects of tyrosinase inhibition, xanthine oxidase inhibition and nitrite-scavenging effects of gamma-irradiated Schizandrae Fructus extracts from different solvents. Schizandrae Fructus was extracted by hot water, ethanol, acetone and methanol, and the extracts were irradiated 10, 20 and 30 kGy with gamma rays. All extracts from Schizandrae Fructus showed inhibition effect against tyrosinase. Tyrosinase inhibition effect of Schizandrae Fructus were higher in solvent extracts than hot water extracts by irradiation. The Schizandrae Fructus extracts had a higher inhibitory effect against xanthine oxidase, and the effect was not changed by irradiation. Nitrite scavenging activity, which was measured at various pH conditions (1.2, 3.0, 6.0), was the highest in Schizandrae Fructus extracts at pH 1.2 and 3.0. Hot water extracts provided higher nitrite scavenging effect than those of the methanol, ethanol and acetone extracts. Gamma-Irradiation may not influence on biological activites of the extracts when irradiated up to 30 kGy.

• Korean Journal of Pharmacognosy
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• v.48 no.1
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• pp.46-50
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• 2017

This study was conducted to investigate the antioxidative activities and tyrosinase inhibition effects of fractions from the distilled water extract of Inonotus obliquus. Moreover, GC-MS based analysis with trimethylsilyl (TMS) derivatization was carried out for active compound in the extract of I. obliquus. In DPPH radical scavenging ability, $SC_{50}$ values of the ethyl acetate fraction was 0.393 mg/ml as a result of the most effective than other fractions. Meanwhile, aqueous fraction showed higher effect in tyrosinase inhibitoty activity. In GC-MS based analysis with TMS derivatization, 7 compounds including syringic acid, vanillic acid and protocatechuic acid were observed in ethyl acetate fraction, and oxalic acid is the main compound in aqueous fraction. As a result, it was confirmed that oxalic acid in aqueous fraction from the distilled water extract of I. obliquus was a compound showing tyrosinase inhibition effect.

• KSBB Journal
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• v.16 no.2
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• pp.220-223
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• 2001

To determine the inhibition of mushroom tyrosinase activity, fresh and dried mugwort, Artemisia princeps was extracted initially with water and ethyl alcohol, and subsequently with hexane, chloroform and ethyl acetate in that order. The highest yield was obtained from the ethyl acetate (15.2%) and hexane (15.5%) fraction of the ethanolic extract of fresh and dried mugwort, respectively. For all fractions tested, the inhibition of tyrosinase activity by fresh mugwort was higher than that of dried mugwort, and the inhibition ratio of tyrosinase activity was 98.9% in the chloroform fraction and 96.7% in the hexane fraction.

• YAKHAK HOEJI
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• v.41 no.4
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• pp.518-523
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• 1997

To isolate biologically active compounds which exhibit tyrosinase inhibition activity and ultimately express skin whitening effect, 14 oriental herbal drugs were screened in ter ms of tyrosinase inhibition. For this purpose, in vitro enzyme assay system for tyrosinase, so called Pomerantz method with some modifications has been established. Crude methanolic extracts from 14 herbal drugs were made and examined for their inhibitory activity against tyrosinase. Those extracts from Cnidii Rhizoma, Arecae Semen, Caryophylli Flos, and Ephedrae Herba showed strong inhibitory activities on mushroom tyrosinase. Therefore, crude methanolic extracts from those 4 herbal drugs were further fractionated using ether, butanol and water. respectively. The ether and n-butanol extracts from Arecae Semen and the n-butanol and water extracts from Caryophylli Flos, respectively, showed relatively strong tyrosinase inhibitory activity compared to arbutin.

• Journal of the Korean Applied Science and Technology
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• v.22 no.1
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• pp.71-76
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• 2005

We extracted pine-needles using ethanol as solvent, and we obtained the refined oil component from pine-needles extract. Also we tested the tyrosinase activated inhibition effect with melanin experiment and analysed with ICP/OES and UV/VIS. Accordingly we obtained the next conclusion from the result of this experiment. From the first result of this experiment, we could know that the degree of recovery of refined oil component from pine-needles extract appeared in about 8.0%. From the second result of this experiment, we could know that the tyrosinase activated inhibition rate increased more and more in case of increasing concentration of pine-needles, green-tea, vitamine-C. Also we could know that vitarnine-C influences to tyrosinase activated inhibition contained in pine-needles. From the third result of this experiment, we could know that inorganic materials of Ca, Mg, V, Mn, etc contained in pine-needles detected with ICP/OES analysis, and the absorbance of pine-needles extract appeared very high in UV/VIS analysis.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.20 no.3
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• pp.51-62
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• 2007

Objective : The aim of this study is to assess the effect of Schizandrae Fructus on melanin synthesis inhibition and whitening effect. Methods : We assessed inhibitory effects of Schizandrae Fructus on melanin-release from B16F10, on melanin production in B16F10, on mushroom tyrosinase activity in vitro, on tyrosinase activity in B16F10 and effect of Schizandrae Fructus on the expression tyrosinase, TRP-1, TRP-2, PKA, ERK-1 ERK-2, AKT-1, MITF in B16F10. Results and Conclusion : 1. Schizandrae Fructus inhibited melanin-release, melanin production in B16F10. 2. Schizandrae Fructus inhibited tyrosinase activity in vitro and in B16F10. 3. Schizandrae Fructus suppressed the expression of tyrosinase, TRP-1, TRP-2, PKA, ERK-2 in B16F10.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.1893-1898
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• 2013

Seaweeds, laver, sea mustard, kelp, and fusiformis, were prepared and investigated for its antioxidant and tyrosinase inhibition activities. The extracts yield, color, total phenolic contents, antioxidative activity, and tyrosinase inhibition activity of the extract samples were measured. Hunter Lightness values of laver, sea mustard, kelp, and fusiformis extracts were 82.88, 78.53, 83.04, and 78.11, respectively. The contents of total phenolic compounds of the seaweed extracts powder, laver, sea mustard, kelp, and fusiformis were 43.23, 11.59, 10.09, and 46.59 mg/g of sample, respectively. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of the fusiformis extract was shown to be the highest value compared with other seaweed extracts. 2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid (ABTS) radical scavenging activities of laver, sea mustard, kelp, and fusiformis extracts were 258.00, 219.26, 95.77, and $1186.62{\mu}mol$ trolox equivalence per gram, respectively, at the 1,000 ppm level. TBARS value of oil emulsion, samples without extracts was higher than those of the samples prepared with laver and sea mustard extracts. The inhibition rates (%) of the mushroom tyrosinase of laver, sea mustard, kelp, and fusiformis extracts powder were 25.93, 26.32, 24.76 and 20.24% at 1,000 ppm, respectively. The results indicated that laver, sea mustard, kelp and fusiformis extracts possess biological activities such as antioxidant activity and tyrosinase inhibition effect.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.891-896
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• 1995

In order to screen natural inhibitor of tyrosinase which catalyzes an enzymatic browning of some foods and in vivo synthesis of melanin, inhibitory effect of 129 edible plants and 15 chemical compounds on the in vivo melanin synthesis by mushroom tyrosinase was analyzed. Among leafy vegetables tested, radish bud, red chicory, Shepherd's purse and small green onion were found to have more than 50% tyrosinase inhibition effect in the descending order. Chinese radish and garlic in root vegetables, and nameko, shiitake and oyster mushroom in mushrooms, and teas showed also more than 50% inhibition effect. Among fruit vegetables tested, red pepper, Chinese quince and avocado were found to have more than 50% tyrosinase inhibition effect, while fruits generally showed low inhibitory effect. Medicinal plants which inhibit tyrosinase more than 50% were mume fructus>cinamomi ramulus>rubi fructus>mori cortex>biotae orientalis folium>puerariae radix, and herbs with more than 50% inhibitory effect were allspice>clove>mustard. In some chemical compounds tested, 4-hexylresorcinol, L-cysteine, glutathione, sodium bisulfite and kojic acid showed powerful inhibition effect on mushroom tyrosinase.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.760-763
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• 2001

To develop a functional beverage from Korean cherry (Prunus tomentosa Thunberg), inhibition effect of ethanol extract and juice of the korean cherry on melanin systhesis and tyrosinase activity in vitro was investigated. Inhibition ratio of tyrosinase activity increased as the concentration of solid of korean cherry juice increased, and inhibition affect was high in initiation step of enzyme reaction and then gradually decreased. Inhibition ratio of tyrosinase activity was high in the 70% (v/v) ethanol extract of the cherry and the highest in the ethyl acetate fraction of the 70% (v/v) ethanol extract. Ultimatly, the amounts of functional matter (melanin synthesis inhibitor) in the cherry was highest in ethyl acetate fraction of the ethanol extract.