• Food Science and Preservation
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• v.7 no.4
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• pp.409-413
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• 2000

Previously, the methanolic extracts of thirty Korean medicinal plant seeds were screened for tyrosinase inhibitors using a rapid and simple TLC method, which was superior to a conventional spectrophotometrical in vitro assay. As a result, the methanolic extracts of Thuja orientalis seeds was found to have strong tyrosinase inhibitory activity. To isolate active tyrosinase inhibitors, the seeds were defatted with n-hexane under reflux, and then extracted twice with methanol under reflux at 90$^{\circ}C$. The methanolic extract was evaporated to a small volumn in vacuo, and then successively fractionated with ether, ethyl acetate and n-butanol. The ether extract showing significant tyrosinase inhibitory activity was solubilized with 5% NaHCO$_3$and then acidified with 6N HCI. The ether souble acidic fraction was successively ohromatographed on silica gel, Sephadex LH-20 and preparative TLC. Among four compounds isolated, two of them showed stronger tyrosinase inhibitory activity, comparable to that of L-ascorbic acid (IC$\sub$50/=28$\mu\textrm{g}$/$m\ell$). These results suggest that Thuja orientalis seeds may be useful as potential sources of antibrowning agents in fruits and vegetables, and anti-melanoma agents in cosmetics and phamaceuticals.

• Advances in Traditional Medicine
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• v.4 no.3
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• pp.187-195
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• 2004

A number of plants from different geographical origins have been shown to possess antioxidant activity. Some of them have been developed as natural antioxidant formulations for food, cosmetic and other applications. Bangladeshi flora is a rich source of a range of plant species, many of which are medicinal plants, and have been used in the preparations of the Unani and Ayurvedic traditional medicines. There are no, or just a few, reports on any systematic screening of the extracts of Bangladeshi plants for free radical scavenging activity using DPPH assay available to date. As part of our on-going search for biological activity in Bangladeshi plants, Kadam (Anthocephalus chinensis), Goran (Ceriaps decandra), Swarnalata (Cuscuta reflexa), Gab (Diospyros peregrina), Sundari (Heritiera fomes), Dhundul (Xylocarpus granatum) and Possur (Xylocarpus mekongensis) have been selected for the assessment of their free radical scavenging activity, and studies on the contents of alkaloids, anthraqunones, flavonoids and tannins in these extracts. Most of these species have been used in traditional medicine in Bangladesh and other countries for the treatment of various illnesses ranging from common cold to cancer. All extracts, except the methanol extract of Cuscuta reflexa, displayed significant free radical scavenging activity in the DPPH assay $(RC_{50}$ values within the range of $2.75\;{\times}\;10^{-2}\;to\;4.7\;{\times}\;10^{-3}\;mg/mL)$. Among these extracts, the methanol extract of Xylocarpus granatum exhibited the most potent activity $(4.7\;{\times}\;10^{-3}\;mg/mL)$ and that of Cuscuta reflexa had the least activity $(1.64\;{\times}\;10^{-1}\;mg/mL)$. While none of these plants showed positive tests with Dragendorff's reagent, presence of low to moderate amounts of phenolic compounds, e.g. anthraquinones, flavonoids and tannins was evident in all of these plants, except for the methanolic extracts of C. reflexa and the barks of D. peregrina, which did not display any evidence for the presence of flavonoids and anthraquinones, respectively.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.662-668
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• 2019

The purpose of this study was to investigate effect of methanolic extracts of 10 kinds of wild vegetables cultivated in Gangwon province on antioxidant activity, acetylcholinesterase, and β-secretase inhibitory activities. Results showed that among the wild vegetables, Aralia elata(Miq.) Seem shoot extract exhibited the highest total phenol content (84.65±1.08 mg GAE/g) and total flavonoids content (70.77±0.55 mg RE/g), respectively. The antioxidant activity of wild vegetables extracts was measured by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay. Aralia elata(Miq.) Seem shoot extracts had the highest DPPH and ABTS scavenging activity (90.16%, 40.18% at 2 mg/mL). As a result, Aralia elata(Miq.) Seem shoot extract was the most effective in terms of acetylcholinesterase inhibitory activity (35.94% at 1 mg/mL). In the β-secretase activity assay, all 10 kinds wild vegetables extracts showed low inhibitory activity, and Aralia elata(Miq.) Seem shoot extract had highest inhibitory activity among the 10 wild vegetables extracts was 14.99%. Taken together, these results showed that Aralia elata(Miq.) Seem shoot extract has potential cognition improvement impact, suggesting that it may provide an effective strategy for improving cognition.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.2 s.51
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• pp.207-212
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• 2005

Pomegranate (Punica granatum L.) which is very rich in Polyphenols and tannins was recently reported its anti-oxidant activities and phytoestrogenic activities in vivo test and many clinical studies, but the effects of them on the skin have not been reported. The experiments were tarried out in vitro to determine anti-oxidant activities of pomegranate extracts on DPPH radical scavenging assay, NBT/Xanthine Oxidase-superoxide scavenging assay, silica-induced intracellular $H_2O_2$, hydroperoxide and superoxide generation assay in RAW 264.7 cells. It showed that the methanolic extract of dried pomegranate peels have the most significant anti-oxidant activities on free radical scavenging assay and inhibitory activities on silica-induced intracellular free radical generation in RAW 264.7 cells. The concentrated juice of pomegranate showed only DPPH radical scavenging activities and inhibited hyaluronidase activity. Moreover, pomegranate seed oil inhibited specially silica-induced intracellular hydroperoxide generation in RAW 264.7 cells. These results suggest that the methanolic extract of dried pomegranate peels and pomegranate seed oil have more anti-oxidant activity than concentrated juice of pomegranate. Thus the extracts of pomegranate peels and seed oil could be developed cosmetic ingredients for anti-aging.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1681-1684
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• 2016

Oats (Avena sativa L.) are well known for having high contents of bioactive compounds and health benefits. The objective of this study was to evaluate the antioxidant compounds and antioxidant activities of methanolic extracts from milling fractions and whole grains of oat. The contents of total polyphenolics and flavonoids were analyzed by spectrophotometric methods. ABTS radical and DPPH radical scavenging activities and reducing power were used to compare relative antioxidant activities of milling fractions from oat. Total polyphenolics and flavonoids were much more abundant in oat bran extract than in extracts from whole grain and endosperm. In addition, high levels of ABTS radical (42.34 mg Trolox equivalent antioxidant capacity (TEAC)/100 g sample) and DPPH radical (24.18 mg TEAC/100 g sample) scavenging activities and reducing power ($A_{700}=0.76$) were detected in oat bran. The results of this study indicate that oat bran has significantly higher antioxidant activities and appears to have significant health benefits.

• Korean Journal of Plant Resources
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• v.31 no.4
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• pp.330-341
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• 2018

This study was performed to investigate and measure the antimicrobial activity of evergreen woody species extracts on Trichophyton mentagrophytes. To do this, leaves and stems were collected from Wando and Jeju islands, and were used for the extraction with different solvents (i.e., distilled water, 80% ethanol, and 100% methanol), and at different ultrasonic extracting times (i.e., 15, 30, and 45 minutes). The experiment was conducted by using the agar diffusion method. The clear zone was measured after incubating the paper disc containing the plant extract in a bacterial culture medium. The controls were synthetic antimicrobials, methylparaben and phenoxyethanol, at concentrations of 0.4, 1, 2, and 4 mg/disc. Altogether, extracts of 56 out of 64 species used in this study had inhibitory activity, which confirmed their antimicrobial activity against Athlete's foot. Among them, the crude ethanolic extract of Elaeocarpus sylvestris in 45 min showed a zone of inhibition < 20.2 mm, while the clear zone of Actinodaphne lancifolia ethanolic extraction for 30 min was 23.5 mm. Also, Quercus acuta, Dendropanax morbiferus and Daphne odora showed clear zones of 28.0 mm (45 minutes ethanolic extraction), 20.5 mm (45 minutes crude methanolic extraction) and 19.7 mm (45 minutes methanolic extraction), respectively. Thus, these results confirm that the extracts of evergreen woody species have therapeutic potential against Athlete's foot, and suggest that in order to extract adequate amounts of antimicrobial substance from the plant sources, ideal extraction condition has to be considered.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.1908-1914
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• 2013

In the present study, the levels of phenolic compounds and flavonoids, as well as activities of radical scavenging (DPPH and ABTS radical scavenging activity) and anti-obesity were assessed with cold water (CLC), hot water (CLH), and methanolic (CLM) extracts of Curcuma longa L. (turmeric). Our results showed that the phenolic compounds of CLC, CLH and CLM were $3.68{\pm}0.80%$, $3.94{\pm}0.74%$ and $9.01{\pm}0.73%$, respectively. The DPPH and ABTS radical scavenging activities of the CLM were significantly higher than that of the water extracts (CLC and CLH). During the adipocyte differentiation, the treatment of CLM more significantly inhibited lipid accumulation in 3T3-L1 cells than that of the water extracts. These results indicate that the stimulation of radical scavenging potential and the inhibition of adipogenesis were brought on by the lipophilic compounds of turmeric.

• Korean Journal of Pharmacognosy
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• v.39 no.4
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• pp.335-340
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• 2008

Diabetes mellitus is metabolic disorder characterized by hyperglycemia caused by insufficient insulin secretion or insulin receptor insensitivity to endogenous insulin. It is well-known that hyperglycemia is one of the main causes of oxidative stress in both type 1 and 2 diabetes. Oxidative stress is related by death of pancreatic ${\beta}$ cell and dysfunction of ${\beta}$ cell. Although ${\beta}$ cell death or dysfunction is induced by many substances or molecules, increased evidences that oxidative stress plays a crucial role in ${\beta}$ cell death or dysfunction. Considering the importance of oxidative stress in the pathogenesis of diabetes mellitus, we investigated the cytoprotective effects against hydrogen peroxide-induced oxidative stress in pancreatic ${\beta}$ cell line RIN-m5F cell. 110 Plant sources were collected in Mt. Baek-du, and extracted with methanol. These extracts had been screened the protective effects against hydrogen peroxide-induced oxidative damage in RIN-m5F cells at 50 and 200 ${\mu}g$/ml. Of these, ten methanolic extracts, aerial part of Erigenron cannadensis, aerial part of Lespedeza juncea, whole plant of Alopecurus aequalis, fruit of Lycium chinense, leaf of Morus alba, rhizome of Polygonatum odoratum, root of Ampelosis japonica, whole plant of Ranunculus japonicus, aerial part of Polygonum sieboldii, rhizome of Arisaema amurense var. violaceum showed significant protective effects against hydrogen peroxide-induced oxidative damage in pancreatic ${\beta}$ cell line RIN-m5F cell.

• The Korea Journal of Herbology
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• v.31 no.3
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• pp.43-48
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• 2016

Objectives : The objective of this research was to investigate the antioxidant activities of stem bark of Maackia amurensis extract.Methods : Stem bark of Maackia amurensis extract were prepared using 70% methanol. Methanol extracts were fractionated to hexane, chloroform, ethyl acetate, butyl alcohol, water fractions and investigated. The antioxidant activities of fractions was evaluated by four different assays as total polyphenol contents, total flavonoid contents, DPPH(1,1-diphenyl-2-picrylhydrazyl) free-radical scavenging activity and ABTS(2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging ability.Results : The yield of methanolic extracts from stem bark of Maackia amurensis was 10.16%, whereas those of its solvent fractions (hexane, chloroform, ethyl acetate, butyl alcohol, and water) were 5.45, 11.39, 13.88, 26.07, and 40.80%, respectively. The total polyphenol contents and electron donating ability of 70% methanol extracts from stem bark of Maackia amurensis were 15.44 mg/g and 194.15 μg/mL of its IC₅₀, respectively. The 70% methanol extracts showed the highest antioxidant activity. The total polyphenol content and total flavonoid content of chloroform fractions were higher in each of 201.98 mg/g and 13.55 mg/g. The chloroform fraction showed the lowest levels of DPPH(IC₅₀, 183.95 μg/mL) and ABTS scavenging activity(IC₅₀, 10.0 μg/mL). The antioxidant activity was detected in methanol extract, chloroform fractions.Conclusions : These results indicate that 70% methanol extract and its fractions of stem bark of Maackia amurensis, especially chloroform fraction, have the properties of anti-oxidant suggesting stem bark of Maackia amurensis may be a candidate for natural and functional materials.

• Korean Journal of Medicinal Crop Science
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• v.17 no.3
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• pp.173-178
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• 2009

A variety of herbs and plants have been traditionally used in oriental folk medicine for the treatment of inflammatory diseases. In our attempt to search for anti-inflammatory agents from natural products, we investigated 64 methanol extracts from 42 medicinal plants belonging to 10 families which were evaluated for inhibitory activities of NO production in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. Among them, 16 extracts exhibited inhibitory activities of NO production ($IC_{50}$ values ranging from 59.6 to 94.7 ${\mu}g/m{\ell}$). Only the extract from aerial parts of Hosta lancifolia (H. lancifolia) did not exert cytotoxic effects at the concentrations tested. The extract from H. lancifolia decreased the mRNA and protein levels of inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines in activated macrophage RAW 264.7 cells in dose-dependent manner. The results suggest that the extract may contain bioactive compounds that suppress expression of pro-inflammatory cytokines, which may prove beneficial with regard to the development of natural agents for prevention and treatment of inflammatory diseases.