• Preventive Nutrition and Food Science
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• v.5 no.3
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• pp.170-173
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• 2000

The inhibitory effect of extracts from 15 edible plants on the protease of human immunodeficiency virus (HIV) type 1 was investigated. Protease activity was determined by incubating the extracts in a reaction mixture containing protease and substrate His-Lys-Ala-Arg-Val-Leu-(p-NO$_2$-Phe)-Glu-Ala-Nle-Ser-NH$_2$ to inhibit proteolytic cleavage. Of various plants tested, the leaves of Cedrela sinensis inhibited the HIV-1 protease by 42% at a concentration of 100$\mu\textrm{g}$/ml. A major flavonoid isolated from the leaves of C. sinensis, quercetin 3-O-$\alpha$-L-rhamnoside showed inhibitory activity of 19% at a concentration of 100$\mu$M.

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.202-206
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• 1999

The MeOH extracts obtained from the leaves of Eucommia ulmoides were solvent-fractionated with EtOAc, n-BuOH, and $H_20$, successively. From the EtOAc extract showing Grab2-Shc inhibitory activity, a flavonol and a lignan compounds were isolated through repeated silica gel column chromatographies. By interpretation of several spectral data and adaptation of acetylation method, the chemical structures of the compounds were determined as 5,7,3',4'-tetrahydroxy-flavonol (quercetin), and 4,4',8',9-tetrahydroxy-3,3'-dimethoxy-7,9'-cyclolignan {(-)-olivil)}, respectively. The compounds exhibited $IC_{50}$ values in Grb2-Shc inhibitory activity to be 93 and $210\;{\mu}mole/l$, respectively.

• Korean Journal of Pharmacognosy
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• v.46 no.3
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• pp.250-259
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• 2015

Advanced glycation end products (AGEs) have been implicated in diabetic complications. In this study, the inhibitory effect on AGEs formation of 156 Korean herbal medicines has been evaluated. Among them, 15 Korean herbal medicines were showed to have significant effect (IC₅₀: <10 μg/ml) compared to positive reference, aminoguandine (IC₅₀: 76.47±4.81 μg/ml). Especially, four herbal medicines, Alnus firma (leaves, IC₅₀: 3.25±0.10 μg/ml), Juncus decipiens (whole plants, IC₅₀: 4.30±0.44 μg/ml), Smilax china (stems, IC₅₀: 3.55±0.21 μg/ml), and Vicia amoena (Aerial parts, IC₅₀: 4.25±0.06 μg/ml) showed more potent inhibitory activity approximately 8-24 fold) than the positive control aminoguanidine.

• Mycobiology
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• v.28 no.4
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• pp.185-189
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• 2000

The antifungal activity of methanolic extracts of Centella asiatica and Andrographis paniculata leaves was observed against fourteen fungi, viz., Alternaria alternata, A. brassicae, A. brassicicola, A. solani, A. tenuissima, Cercospora blumae, Curvularia lunata, C. penniseti, and Drechslera monoceras, D. oryzae, D. turitica, Fusarium albizziae and F. udum. Different concentrations of the methanolic extract (1000, 2000, 3000, 5000, 7000, 10000ppm) were used. The effect of mixed leaf extract (1500 ppm of C. asiatica + 1500 ppm of A. paniculata) and its 1:2 ad 1:4 dilutions were also studied. The individual extracts of both the plants showed significant inhibitory effect on spore germination of all the fungi tested. F. udum, F. albizzae, D. oryzae, D. turtica, and D. monoceras were particularly sensitive to these extracts. In general, the extract of C. asiatica showed a higher inhibitory effect in all concentrations against all the fungi as compared to A. paniculata, except for A. brassicae A. solani, D. oryzae, D. penniseti and Curvularia sp. The inhibitory effect of extracts increased when they were used in combination with or without dilutions against A. brassicicola, A. solani A. brassicae, A. alternata, A. tenussima, C. blumae, C. lunata, C. penniseti and Curvularia species. Higher efficacy of active ingredient of these extracts under field condition is envisaged against plant pathogens.

• Korean Journal of Pharmacognosy
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• v.34 no.1 s.132
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• pp.100-108
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• 2003

The regulation of plasma lipid level, particularly LDL cholesterol, represents the focus of current therapy for atherosclerosis. And $Lp-PLA_2$ is able to hydrolyse oxidized phosphatidylcholine within LDL into lyso-PC and oxidized fatty acids. $Lp-PLA_2$ is a potential biomarker of coronary heart disease and plays an important proinflammatory role in the progression of atherosclerosis. We investigated the inhibitory effects of methanol extracts of 224 natural plants on $Lp-PLA_2$ activity. Seven kinds of methanol extracts of tested plants showed above 50% inhibitory effect with the concentration of $100\;{\mu}g/ml$. The concentrated aqueous suspensions of each methanol extract were partitioned with n-hexane, $CHCl_3$, and EtOAc. Among them, EtOAc extracts of Astilbe chinensis var. davidii (root) and Pourthiaea villosa var. brunnea (leaf) significantly inhibited $Lp-PLA_2$ activity at the same concentration.

• Journal of the Korean Applied Science and Technology
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• v.26 no.2
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• pp.110-116
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• 2009

In an attempt to find natural sources of antioxidants and whitening agents, Comparisons of the antioxidative and tyrosinase inhibitory activities of various ethanol extracts of Astragali Radix, Atractylodis Rhizoma Alba and Acanthopanacis Cortex were carried out. Comparison of the four ethanol extracts revealed that, Astragali Radix had the highest electron-donating ability(72.5%) and the highest SOD-like ability(26.1%). The xanthine oxidase experiment exhibited a hindrance effect of 88.5% in Atractylodis Rhizoma Alba, 81.1% in Acanthopanacis Cortex, 75.8% in Astragali Radix. A tyrosinase inhibitory activity assay was conducted to evaluate the whitening effects of the extracts, The tyrosinase inhibitory activity was 42.1% in the Acanthopanacis Cortex, 37.2% in the Atractylodis Rhizoma Alba, 6.0% in the Astragali Radix. Based on these results, we suggest that the ethanol extracts of Astragali Radix, Atractylodis Rhizoma Alba and Acanthopanacis Cortex can be used as food and cosmetic ingredients.

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1806-1813
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• 2018

A new sesquiterpene lactone dimer [1], together with five known compounds (2-6), was isolated from the flowers of Inula britannica. The structures of these compounds were established by extensive spectroscopic studies and chemical evidence. The inhibitory activities of these isolated compounds (1-6) against human neutrophil elastase (HNE) were also evaluated in vitro; compounds 1 and 6 exhibited significant inhibitory effects against HNE activity, with $IC_{50}$ values of 8.2 and $10.4{\mu}m$, respectively, comparable to that of epigallocatechin gallate (EGCG; $IC_{50}=10.9{\mu}M$). In addition, compounds 3 and 5 exhibited moderate HNE inhibitory effects, with $IC_{50}$ values of 21.9 and $42.5{\mu}M$, respectively. In contrast, compounds 2 and 4 exhibited no such activity ($IC_{50}$ > $100{\mu}M$). The mechanism by which 1 and 3 inhibited HNE was noncompetitive inhibition, with inhibition constant ($K_i$) values of 8.0 and $22.8{\mu}M$, respectively.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.2
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• pp.63-70
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• 1997

It has been observed that local increase in melanin synthesis or uneven distribution can cause local hyperpigmintation or spot. Pigmentary disorders are caused by various factors, including inflammation, imbalance of hormones, and genetic disorder. Recently the harmfulness of Ultraviolet radiation is increasing due to destruction of ozone layer. Excessive exposure to UV radiation caused post-inflammatory pigmentation. Most women want to avoid uneven skin pigmentation. To satisfy this desire many cosmetic companies have been developing melanogenesis inhibitors and finding promising active agents for use in cosmetic preparations for skin whitening. In cosmetic preparations, many inhibitors such as kojic acid, arbutin, ascorbic acid, and licorice extracts6 have been used as whitening purpose. Plant extracts having an inhibitory effect on melanin formation may be a good choice for cosmetic purpose because of their relatively lower side effects. Therefore, we screened 285 plant extracts for their inhibitory activity in tyrosinase. Of the plant extracts, ramulus mori extracts showed potent tyrosinase inhibition activity. We also identified the active compound in the extract.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.111.2-112
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• 2003

A total of 20 extracts derived from different plant family commonly used in Indonesian traditional inflammation medicine were screened for their inhibitory effect on soybean lipoxygenase (SBL) and hyaluronidase (HAse) activity. Three methanol extracts, the bark of Cinnamomum burmanni (CB), the leaves of Piper betel (PB), and fruit of Barringtonia acutangula (BA) were found to have high inhibitory effects, whereas the methanol extract of the leaves of Mimusops elengi (ME) have medium inhibitory effect. The IC50 of CB, PB, BA and ME were found to be 21.7, 16.9, 39.1 and 62.8 g/$m\ell$, respectively. Among the tested extracts, only CB inhibited HAse (IC50 = 27g/$m\ell$). CB was successively fractionated with n-hexane, ethyl acetate, butanol and water. The EtOAc fraction having the strongest activity was fractionated and some compounds were isolated and purified by a preparative HPLC(Develosil ODS-HG-5 column). Coumarin and 2-hydroxy cinnamaldehyde. were identified through the analyses of UV-Vis absorption 1H-NMR, 13C-NMR and FAB+-MS spectra.

• Journal of East-West Nursing Research
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• v.14 no.2
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• pp.74-80
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• 2008

Purpose: To screen candidate oriental herb material for antimelanogenics. Methods: Oriental herbs (n=100) were screened for mushroom tyrosinase inhibitory activity in vitro using the HM3KO human melanin cell line cultured in DMEM supplemented with 10% fetal bovine serum. Cytotoxicity was assessed by a cell viability assay involving 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), Trypan Blue exclusion, and cell enumeration. Results: Tyrosinase inhibitory effects on 100 oriental herbs was evident. Of these, 11 herbs inhibited tyrosinase activity by 40% without being cytotoxic to HM3KO cells. Three herb varieties significantly decreased melanin synthesis in HM3KO cells. Conclusions: Oriental herb can have antimelanogenic effects indicating their potential for functional therapeutic use in dermatological whitening.