• BMB Reports
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• v.37 no.5
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• pp.597-602
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• 2004

N-terminal His-tagged recombinant $\beta$-1,4-galactosyltransferase from Neisseria meningitidis was expressed and purified to homogeneity by column chromatography using Ni-NTA resin. Mutations were introduced to investigate the roles of, Ser68, His69, Glu88, Asp90, and Tyr156, which are components of a highly conserved region in recombinant $\beta$-1,4 galactosyltransferase. Also, the functions of three other cysteine residues, Cys65, Cys139, and Cys205, were investigated using site-directed mutagenesis to determine the location of the disulfide bond and the role of the sulfhydryl groups. Purified mutant galactosyltransferases, His69Phe, Glu88Gln and Asp90Asn completely shut down wild-type galactosyltransferase activity (1-3%). Also, Ser68Ala showed much lower activity than wild-type galactosyltransferase (19%). However, only the substitution of Tyr156Phe resulted in a slight reduction in galactosyltransferase activity (90%). The enzyme was found to remain active when the cysteine residues at positions 139 and 205 were replaced separately with serine. However, enzyme reactivity was found to be markedly reduced when Cys65 was replaced with serine (27%). These results indicate that conserved amino acids such as Cys65, Ser68, His69, Glu88, and Asp90 may be involved in the binding of substrates or in the catalysis of the galactosyltransferase reaction.

• Mycobiology
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• v.30 no.1
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• pp.55-56
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• 2002

The 4',7-dimethoxyisoflavone was isolated from the leaves of Albizzia lebbeck for the first time. This flavonoid showed antifungal activity against some plant pathogenic fungi tested in vitro, e.g., Alternaria melongenae, A. brassicicola, A. brassicae, Curvularia maculans, C. pallescens, C. lunata, Curvularia species, Colletotrichum species, Helminthosporium penniseti and H. speciferum. The sensitivity of different fungi to this chemical varied considerably. A. brassicae was most sensitive as complete inhibition of germination was observed in all the concentrations(100 to 1000 ppm) of the chemical. Similar effect on H. speciferum and Curvularia species was also recorded at 500 ppm, whereas H. penniseti did not germinate at 250 ppm. A. melongenae and A. brassicicola also did not germinate at 1000 ppm while 750 ppm was inhibitory to C. lunata and C. maculans. Germination in almost all fungi was significantly inhibited at each concentration in comparison to control except Curvularia sp. and H. speciferum. Use of 4',7-dimethoxyisoflavone to control some plant diseases under field conditions has been suggested.

• Preventive Nutrition and Food Science
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• v.7 no.1
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• pp.62-66
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• 2002

As inhibitors of carbohydrate-digesting enzymes can prevent hyperglycemia that is known to cause many macrovascular complications, they may prove a useful adjunct to hypocaloric diets in patients with type 2 diabetes and obesity. Inhibitory activities of two hundred and fifteen kinds of medicinal herb extracts against $\alpha$-glucosidase (EC 3.2.1.20) and $\alpha$-amylase (EC 3.2.1.1) have been investigated in vitro. Adenophora triphylla, Aneilema keisak, and Morus bombysis significantly suppressed rat intestinal $\alpha$-glucosidase activity iu vitro. Porcine pancreatic amylase was efficiently inhibited by methanol extracts of Epimedium koreanum, Campsis grandiflora and Salvia plebeia. Methanol extract of Epimedium koreanum among the medicinal herbs tested showed the strongest inhibitory activity against porcine pancreatic $\alpha$-amylase with 0.1 mg/ML of $IC_{50}$/. The herb extract also improved glucose tolerance in ICR mice when loaded with 0.9 g soluble starch per kg body weight. Taken together, Epimedium koreanum merits further evaluation as a therapeutic measure.

• Korean Journal of Medicinal Crop Science
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• v.16 no.3
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• pp.139-143
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• 2008

The antioxidant activities of Agrimony (Agrimonia pilosa L.) and Chinese lizardtail (Saururus chinensis Baill) according to extraction methods were measured. SOD-like activity showed greater antioxidant effects with ethanol solvent than those with water. Ethanol extracts of Agrimony leaves showed the highest SOD-like activity of 94.4%. SOD-like activity differed according to the extraction solvents. The contents of polyphenolic compounds were higher in water extracts than those in ethanol extracts. The contents were 161.4 mg for Agrimony roots, 100.2 mg for Agrimony leaves, and 79.1 mg for Agrimony stalks in order. EDA in Agrimony leaves that were highest among medicinal plants were 83.4% in the water extract and 81.7% in the ethanol extract. The anticancer effects of the extracts by water and ethanol from Agrimony and Chinese lizardtail were experimented. The growth of stomach cancer cells, SNU-719 was inhibited 94.5% by the hexane fractions of Agrimony and also the growth of liver cancer cells, Hep3B was inhibited 83.2% by the hexane fractions of Agrimony, while the growth of normal cell, DC2.4 was not affected.

• Journal of Marine Bioscience and Biotechnology
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• v.5 no.4
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• pp.8-14
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• 2011

Although marine living organism contains a numerious number of compounds, it is difficult to collect these compounds in a large scale for medicinal application. However, in recent years, several bioactive compounds isolated from marine macroalgae have been proved to be able to provide potential sources for development of medicinal products because they can be obtained in large amount from marine. A number of studies have reported a variety of effects of marine macroalgae but a few anti-inflammatory activity of marine macroalgae have recently been published. Herein, we reviewed novel anti-inflammatory compounds recently isolated from marine brown algae, green algae and red algae. From this survey, in particular, some compounds contained in edible macroalgae exert anti-inflammatory effects with inhibition on cyclooxygenase-2 (COX-2), inducible nitric oxide synthase(iNOS) and matrix metalloproteinases (MMPs) activity regulated by nuclear factor-kappa B transcription factor that play a key role in cancer as well as inflammation, demonstrating to be able to potentially apply to development of anti-inflammatory agent for chemoprevention of cancer. Furthermore, some macroalgae and their compounds with both excellent anti-inflammatory activity and very low toxicity can select a potential candidates capable of preventing or treating several chronic inflammation such as colitis, hepatitis and gastritis, leading to cancer.

• Korean Journal of Medicinal Crop Science
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• v.15 no.5
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• pp.329-334
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• 2007

The potential antioxidant and anticancer activities of Hexane, EtOAc (Ethyl acetate), BuOH (n-Buthanol) and water fractions from methanolic (MeOH) extract of Picrasma quassioides (D. Don) Benn. were evaluated in vitro. Tested fractions showed strong antioxidant activity, especially EtOAc fraction had the highest activity ($IC_{50}\;=\;114.01\;{\mu}g/mL$), containing high total phenolics and total flavonoids contents, showed $67.59\;Tan\;{\mu}g/mg$ and $64.95\;Que\;{\mu}g/mg$ respectively. Anticancer activity of these fractions was tested by MTT assay on HT-29 (the human colon carcinoma cells) cell line. BuOH fraction not only showed very high anticancer activity, but also had no cytotoxic effect on 293 (the human normal kidney cells) cell line. Considering these results, we used BuOH fraction of MeOH crude extract from P. quassioides (D.Don) Benn. to do assessment of apoptosis by flow cytometry and the mRNA expression levels of widely established apoptotic-related genes on HT-29 cell line. All the experiments showed that BuOH fraction can induce apoptosis on HT-29 cell line strongly. Taken together, methanolic extract of P. quassioides has potential for antioxidant and anticancer activities products.

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.94-101
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• 2000

On the purpose of development of antioxidative compounds from natural sources, 38 plants known to have antioxidant activity have been examined concerning DPPH radical scavenging activity. Among 13 plants exhibiting the activity, the seed of Carthamus tinctorius L, was selected as resources to search for active compounds due to rareness of study. The seed of the plant has been used as edible oil or preventive and remedial drugs for osteoporosis, arthritis. To reveal the principal component manifesting the antioxidant activity, the MeOH extracts was successively solvent-fractionated with EtOAc, n-BuOH and water. In order to isolate active component from the EtOAc fractions, application of silica gel column chromatographies and activity tests were repeated for a active component to be isolated. Its chmical structure was determined to be N-feruloylserotonin, a conjugated serotonin compound, by the interpretation of spectral data, NMR. MS and the adaptation of chemical reactions.

• The Korea Journal of Herbology
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• v.26 no.1
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• pp.111-117
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• 2011

Objectives : The present study was designed to investigate effects of mixed extract from korean medicinal herbs (MIX) on oxidation/reduction reaction-related and aging-related enzyme in vitro. Methods : We performed MTT assay, collagenase inhibition assay, elastase inhibition assay, tyrosinase inhibition assay, DPPH free radical scavenging assay, SOD-like activity and xanthine oxidase inhibition assay. Results : Recently, many studies have reported that elastin is also involved in inhibiting or repairing wrinkle formation, although collagen is a major factor in the skin wrinkle formation. The MIX showed 97% inhibition of collagenase activity, and 64% inhibition of elastase activity at 1 mg/ml concentration of MIX, next only to positive control, which indicate good efficacy for anti-wrinkle ingredient. Also it's treatment showed 34% inhibition of tyrosinase activity, to relate whitening effect, at the same dose of MIX. Antioxidant activities were determined by DPPH radical scavenging, xanthine oxidase (XO) inhibiting activity and SOD-like activity. Also these scavenging, XO-inhibiting and SOD-like activities were measured in 91%, 80%, and 63% inhibition, respectively, at a treated dose of 1 mg/ml, compare to control. Conclusions : These results suggest that possibility of mixed korean medicinal herbs as a functional ingredient for anti-wrinkle and whitening, anti-oxidation and anti-aging cosmetic formula.

• Korean Journal of Pharmacognosy
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• v.46 no.1
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• pp.84-92
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• 2015

Tyrosinase is a key enzyme to control the biosynthesis of melanin pigments and has two enzyme activities, namely of 1-tyrosine hydroxylase and of 1-dopa oxidase. Thus, tyrosinase is regarded as a target in skin-whitening and therapeutic intervention of local hyperpigmentation diseases. We have tested tyrosinase inhibitory activity on the water extracts of 50 species oriental medicinal plant. Among them, five medicinal plants, Linderae Radix, Clematidis Radix, Cinnamomi Cortex Spissus, Fritillariae Thunbergii Bulbus and Bulbus Fritillariae Cirrhosae were investigated strong inhibition effect. Five medicinal plants were fractionated using organic solvents (methylene chloride, ethyl acetate, n-butanol, water). Cinnamomi Cortex Spissus (ethyl acetate fraction) was investigated strong inhibition effect. Tyrosinase inhibitory activity below $IC_{50}\;40{\mu}g/ml$ is confirmed in five herbal plants that are Linderae Radix, Clematidis Radix, Cinnamomi Cortex Spissus, Fritillariae Thunbergii Bulbus and Bulbus Fritillariae Cirrhosae. Tyrosinase inhibitory levels ($IC_{50}\;{\mu}g/ml$) of each plants were 15.56, 35.02, 25.14, 15.20 and 39.77. We also investigate the effect of effective plant's fraction. in dose of $100{\mu}g/ml$, Cinnamomi Cortex Spissus (P-36) EtOAc fraction significant inhibitory effect over 50%. Clematidis Radix (P-35) and Cinnamomi Cortex Spissus (P-36) MC fraction inhibit tyrosinase each 36.60% and 43.21%. inhibitory rates of Fritillariae Thunbergii Bulbus (P-40) EtOAc and $H_2O$ fraction are 31.40% and 31.51%. Bulbus Fritillariae Cirrhosae (P-45) BuOH fraction regulate tyrosinase activity to 37.71%. We examined tyrosinase inhibitory activity of natural products and these results suggest that several herbs have potential as a new whitening material.

• Korean Journal of Medicinal Crop Science
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• v.24 no.3
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• pp.183-190
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• 2016

Background: This study determined the effects of mulching, an environment friendly organic cultivation method, on antioxidant compound contents and growth in Codonopsis lanceolata, commonly known as Deodeok. Methods and Results: C. lanceolata was treated by mulching with several different methods (a non-woven fabric, biodegradable film, or rice husks) and also treated with hand weeding. A non-treatment plot was used as a control. The growth and levels of weed control in C. lanceolata were better in plants cultivated under mulching treatments (non-woven fabric, biodegradable film, and rice husks) than in those under non-mulching treatments (hand weeding and non-treatment). The contents of antioxidant compounds, such as total flavonoids, phenolics, and anthocyanins, were highest under the biodegradable film treatment, followed by the non-woven fabric treatment, rice husks treatment hand weeding, and non-treatment. There were identifiable differences in DPPH and ABTS activity in comparison to antioxidant compound content by solvent fractions. Mulching treatments resulted in higher DPPH scavenging activity in water and ethyl ether fractions and ABTS scavenging activity in n-butanol fractions than in other fractions, as opposed to hand weeding and non-treatment groups, although total activity of DPPH and ABTS did not increase with mulching treatments. Conclusions: Mulching C. lanceolata with biodegradable film and non-woven fabric is an effective method for improving plant growth and inhibiting the occurrence of weeds as well as for increasing antioxidant compound content and altering antioxidant activity.