• 한국지역사회생활과학회지
• /
• 제15권4호
• /
• pp.11-16
• /
• 2004

This study was conducted to find the powerful free radical scavenging effect in methanol extracts from 35 kinds of Korean medicinal plants obtained from the Plant Extract Bank as natural plant products. Antioxidant activity of the plant extracts was determined by measuring the scavenging effect of 1,1-diphenyl-2-picryl hydrazyl radical (DPPH). In the screening of plant extracts tested, at 200 ppm level, almost all plantex tracts showed significantly high antionidant activity. In the reinvestigation of 15 kinds of Korean medicinal plants at 50 ppm level selected as good sources with good free radical scavenging effect at 200 ppm level, the DPPH scavenging effects were similar to those of L-ascorbic acid in whole plant extract of Fragaria yezoensis (90.4％), in the plant stems and roots extract of Gingko biloba, and the leaves extract of Rhododendron mucronulatum var. ciliatum (90％). The fruits extract of Cornus officinalis showed the strongest antioxidant activity (95％). These results suggest that the methanol extracts from Korean medicinal plants can be a potential source of antioxidants that can be used to control oxidative stress in the body, But further study is needed to measure their safety for consumption

• Natural Product Sciences
• /
• 제24권2호
• /
• pp.82-87
• /
• 2018

Silymarin is the standardized extract from Silybum marianum which consists mainly of flavonoids and polyphenols. It is highly regarded for its hepatoprotective ability. Silybin B is a flavonolignan and one of the active components of silymarin. The content of silybin B in various parts of S. marianum was analyzed by HPLC-UV. Results show that the extract of seeds contain the highest amount of silybin B (7.434 mg/g DW). The petioles of S. marianum showed a low content of silybin B. This study revealed that seeds of S. marianum contain high amount of silybin B and could be a good source of the compound.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
• /
• pp.186-186
• /
• 1998

Persicaria lapathifolia Gray (Polygonaceae) is a common weed in Korea. This plant and other Persicaria species including P. orientale and P. pubescens have been used as an analgesic and stomachic as well as for the treatment of rheumatoid arthritis and malaria. During the screening program of plant extracts, MeOH extract of P. scabrum showed anticomplement activity and the MeOH extract was partitioned with hexane, chloroform, ethyl acetate, and buthanol. EtOAc fraction showed strong activity and activity guided separation yielded eight flavonoids. Two known galloylated and a novel ferulloylated flavonoid glycosides showed strong anticomplement activity. Other flavonoid glycosides, kaempferol 3-O-${\alpha}$-$\sub$L/-arabinopyranoside, kaempferol 3-O-${\beta}$-$\sub$D/-glucopyranoside, kaempferol 3-O-${\beta}$-$\sub$D/-galactopyranoside, quercetin 3-O-${\alpha}$-$\sub$L/-arabinopyranoside, quercetin 3-O-${\beta}$-$\sub$D/-glucopyranoside, quercetin O-${\beta}$-$\sub$D/-galactopyranoside did not showed anicomplement activity.

• Food Science and Biotechnology
• /
• 제17권4호
• /
• pp.846-849
• /
• 2008

This study employed high performance liquid chromatography (HPLC) coupled to an on-line $ABTS^+$ radical scavenging detection (RSD) system along with HPLC-electro spin impact/mass spectrometry (ESI/MS), to rapidly determine and identify antioxidant compounds occurring in blueberry extract. The extract was separated by HPLC, and then the radical scavenging activities of the separated compounds were evaluated by the on-line coupled $ABTS^+$-RSD system. The negative peaks of the $ABTS^+$-RSD system, which indicates the presence of antioxidant activity, were monitored by measuring the decrease in absorbance at 734 nm. The active components in the blueberry extract were identified by HPLC-ESI/MS using their MS spectra and retention times. According to the data acquired from the on-line HPLC-$ABTS^+$-based assay and HPLC-ESI/MS systems, the antioxidant compounds detected in the blueberry extract were identified as chlorogenic acid and 11 anthocyanins.

• The Plant Pathology Journal
• /
• 제35권5호
• /
• pp.406-416
• /
• 2019

Strawberry, an important fruit crop, is susceptible to a large number of pathogens that reduce fruit quality and productivity. In this study, the effect of a biostimulant prepared from Ascophyllum nodosum extract (ANE) (0.1%, 0.2%, and 0.3%) was evaluated on powdery mildew progression under greenhouse and field conditions. In the greenhouse, application of 0.2% ANE showed maximum reduction in powdery mildew progression as compared to the control. Forty-eight hour post-inoculation, foliar spray of 0.2% ANE reduced spore germination by 75%. Strawberry leaves sprayed with ANE showed higher total phenolic and flavonoid content in response to powdery mildew infection. Furthermore, application of ANE elicited defense response in strawberry plants by induction of defense-related enzymes, such as phenylalanine ammonia lyase, polyphenol oxidase, and peroxidase activity. In field conditions, foliar spray of 0.2% ANE showed a reduction of 37.2% of natural incidence of powdery mildew infection as compared to the control. ANE sprayed plant also reduces the severity of powdery mildew infection under natural conditions. These results indicate that application of ANE induces the strawberry plant's active defense against powdery mildew infection by induction of secondary metabolism and regulating the activities of defense-related enzymes.

• Archives of Pharmacal Research
• /
• 제27권1호
• /
• pp.118-126
• /
• 2004

The aqueous extract of European mistletoe (Viscum album, L.) has been used in cancer therapy. The purified mistletoe lectins, main components of mistletoe, have demonstrated cytotoxic and immune-system-stimulating activities. Korean mistletoe (Viscum album L. coloratum), a subspecies of European mistletoe, has also been reported to possess anticancer and immunological activities. A galactose- and N-acetyl-D-galactosamine-specific lectin (Viscum album L. coloratum agglutinin, VCA) with Mr 60 kDa was isolated from Korean mistletoe. Mistletoe preparations have been given subcutaneously due to the low stability of lectin in the gastrointestinal (GI) tract. In the present study, we investigated the possibility of alginate/chitosan microcapsules as a tool for oral delivery of mistletoe lectin. In addition, our strategy has been to develop a system composed of stabilizing cores (granules), which contain mistletoe lectin, extract or powder, coated by a biodegradable polymer wall. Our results indicated that successful incorporation of VCA into alginate/chitosan microcapsules has been achieved and that the alginate/chitosan microcapsule protected the VCA from degradation at acidic pH values. And coating the VCA with polyacrylic polymers, Eudragit, produced outstanding results with ideal release profiles and only minimal losses of cytotoxicity after manufacturing step. The granules prepared with extract or whole plant produced the best results due to the stability in the extract or whole plant during manufacturing process.

• Journal of Pharmaceutical Investigation
• /
• 제40권5호
• /
• pp.269-275
• /
• 2010

P-gp plays a critical role in drug disposition and represents a mechanism for the development of multidrug resistance. Flavonoids, a major class of natural compounds widely present in foods and herbal products, have been shown to inhibit P-gp. Therefore, the aim of this study was to identify new candidate chemosensitizers by screening various plant extracts. The ability of natural plant extracts to inhibit P-gp activity was assessed by measuring cellular accumulation of calcein AM, daunorubicin and vincristine in P-gp overexpressing MDCKII-MDR1 cells. Among more than 800 plant extracts, eight were found to inhibit P-gp activity. Curcuma aromatica extract produced greatest inhibition, followed by Curcuma longa and Dalbergia odorifera extracts. Extracts of Aloe ferox, Curcuma zedoariae rhizome, Zanthoxylum planispinum, and Ageratum conyzoides showed moderate inhibitory effects. Curcumin and quercetin exhibited similar inhibition of P-gpmediated efflux of daunorubicin and vincristine, and flavones had a lesser effect. When chemosensitizing effect was evaluated by measuring daunorubicin sensitivity to MDCKII-MDR1 cells in the presence of natural plant extracts, Curcuma aromatica showed the most potent chemosensitizing effect based on daunorubicin cytotoxicity. In conclusion, natural plant extracts such as Curcuma aromatica can potently inhibit P-gp activity and may have potential as a novel chemosensitizers.

• The Plant Pathology Journal
• /
• 제17권5호
• /
• pp.264-270
• /
• 2001

The effects of leaf extracts of 14 different non-host plant species on in vitro conidial germination of Phaeoisariopsis personata, the causal organism of late leaf spot(LLS) of groundnut were evaluated. Aqueous and ethanol leaf extracts of Datura metel, Lawsonia inermis and aqueous leaf extracts of Sphaeranthus indicus at 25%(w/v) concentration completely inhibited the conidial germination of P. personata both at 24h and 48h after incubation. Aqueous leaf extracts of Blumea bifoliata, Eucalyptus globules, Ocimum sanctum and Pongamia pinnata, and ethanol leaf extracts of Azadirachta indica and S. indicus inhibited the conidial germination by >90%. Aqueous and ethanol leaf extract of L. inermis and S. indicus were highly inhibitory to conidial germination up to 1% concentration. Aqueous and ethanol leaf extracts of D. metel and ethanol leaf extract of A. indica were highly inhibitory to P. personata even at 0.01% (100 ppm) concentration. Ethanol leaf extract of A. indica up to $80^{\circ}$, aqueous leaf extracts of D. metel and S. indicus up to $100^{\circ}$, and L. inermis up to $60^{\circ}$, were highly stable and retained their fungitoxic effects. Extract of D. metel was antifungal even after 180 days when it was stored both at room temperature and $4^{\circ}$. Aqueous leaf extract of D. metel at 2% concentration effectively reduced the development of LLS by >60%, under greenhouse conditions both in prophylactic and simultaneous applications. Extracts of D. metel could be a potential economical and an eco-frendly alternative for control of late leaf spot, and its efficacy under field conditions is further being evaluated.

• 한국작물학회지
• /
• 제60권3호
• /
• pp.366-373
• /
• 2015

This study was conducted to clarify the antimicrobial effect, antioxidant and tyrosinase inhibitory activities of the biological composition having the Phytolacca americana, and to enhance the natural materials utilization of foods and cosmetics. The antimicrobial activities of the different parts of P. americana were evaluated using the agar diffusion test. The antimicrobial activity of P. americana was relatively high in Malassezia furfur known as a skin fungi and Vibrio parahaemolyticus compared to Escherichia coli and Staphy-lococcus epidermidis. However, the antimicrobial activity in Vibrio parahaemolyticus did not show at all parts of P. americana. Both the DPPH radical scavenging activity and ABTS radical scavenging activity have been increased with the higher concentration of methanol extract. In particular, leaf extract of P. americana exhibited the highest activity both ABTS radical scavenging activity and DPPH radical scavenging activity. The nitrite scavenging activity was decreased when the pH was changed from pH 1.2 to pH 6.0. The highest nitrite scavenging activity was exhibited from the methanol extract of fruit, followed by root, stem, and leaf at pH 1.2. However, the nitrite scavenging activity at pH of 6.0 was not almost detected. All plant parts of P. americana showed tyrosinase inhibitory activity. The highest activity was found in the stem, and followed by root, leaf, and fruit in order. These tyrosinase inhibitory activity was progressively increased in a concentration-dependent manner. In this experiment on the methanol extracts of different organ from P. americana, we confirmed that the extract of P. americana showed potent tyrosinase inhibitory activity. Taken together, we conjectured that the P. americana had the potent biological activities, therefore this plant having various functional components could be a good material for development into source of natural food additives and cosmetics.

• Plant Resources
• /
• 제8권2호
• /
• pp.96-102
• /
• 2005

As part of developing natural food preservatives, the antimicrobial effect of ethanol and water extracts from the Cruciferous vegetable was examined Korean traditional Brassica juncea Coss. was used widely as an ingredient of Kimchi, a natural flavoring and spice for a long time. Antimicrobial activities were examined against 15 microorganisms which were food-born pathogens and/or food poisioning microorganisms and food-related bacteria and yeasts. Ethanol extract from leaf mustard showed an antimicrobial effect in most of the strains used in the present study. The lowest minimum inhibitory concentration (MIC) were seen in Bacillus subtilis and Bacillus natto at 10 mg/ml. MIC of water extract was 40-60 mg/ml for bacteria and yeast. Antimicrobial activity of the ethanol extract was not disappeared by the heating at $121^{\circ}C$ for 15 min and not affected by pH.