• Korean Journal of Medicinal Crop Science
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• v.11 no.4
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• pp.264-267
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• 2003

Korean medicinal plants were screened for their inhibitory activity against HIV-1 protease. The inhibitory activity of protease was determined by incubating the extracts in reaction mixtures containing protease and substrate $His-Lys-Ala-Arg-Val-Leu-(p-NO_{2}-Phe)-Glu-Ala-Nle-Ser-NH_{2}$ to perform proteolytic cleavage reactions. In this study the twenty six extracts from medicinal plants were investigated. Of the extracts tested, the extracts from the stem of Morus alba. exhibited the strongest activity with inhibition of 81% at a concentration of $100{\mu}g/ml$. The extracts of the flower of Saxjfraga stolonifera, and stems of Euonymus japonica and Castanea crenata showed appreciable inhibitory activity (>50%) against HIV-1 protease at same concentration.

• Korean Journal of Medicinal Crop Science
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• v.12 no.2
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• pp.108-112
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• 2004

Four medicinal plants selected from preliminary screening study were evaluated in the aspects of their antioxidant activities in alcohol-intoxicated rats. Rats fed 1% ${\alpha}-tocopherol-supplemented$ diet as positive control and ones done ${\alpha}-tocopherol-deficient$ diet as negative control were compared with ones done the plant extract-supplemented diet (n=8). After the administration of the experimental diets for 4 weeks, typical increments in activities of manganese-superoxide dismutase (Mn-SOD) and glutathione peroxidase (GSH-px) indicated in alcohol-intoxicated rats, were not observed in ones fed Lagerstroemia and Ulmus extract-supplemented diet. The content of thiobarbituric acid reactive substance (TBARS), the product of lipid peroxidation, did not increased in rats fed plant extracts-supplemented diet except for Terminalia. From the results, it is concluded that Lagerstroemia and Ulmus have physiologically efficient antioxidant activities.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.671-676
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• 2012

This study was conducted investigate the effect of medicinal plant extracts on physiological and sensory characteristics. The medicinal plant extracts were added to chocolate at a weight percentage of 0, 3 and 6%. Color values(L-value, redness, and yellowness), total flavonoids, DPPH radical scavenging activity, and sensory characteristics made with varying various medicinal plants concentrations of the additives were measured. In sensory evaluation, significant differences(p<0.05 and p<0.01) were shown in taste, texture, and overall acceptability depending on the addition of plant extracts, but there were no significant differences in chocolate aroma and bitterness properties.

• Food Science and Preservation
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• v.19 no.5
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• pp.744-750
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• 2012

In this study, the optimal conditions for phenolic-compound extraction from medicinal plants were found to be 24 h and about 50% ethanol. The electron-donating scavenging activities (DPPH), ABTS radical-cation decolorization (ABTS), antioxidant protection factor (PF), and thiobarbituric acid reaction substance (TBAR) were measured to determine the antioxidant activities of the extracts of Sanguisorba officinalis Linn., Citrus unshiu Markovich, Melia azedarach L., Asparagus cochinchinensis Merr., Citrus unshiu S., Polygonum aviculare L., and Leonurus sibiricus L. The total phenolic contents of the extracts of medical plants were determined to be 0.45-3.00 mg/g in the water extracts and 0.33-3.15 mg/g in the 50% ethanol extracts. The electron-donating abilities (EDA) of the water and ethanol extracts were both above 85% at the $50{\mu}g/ml$ concentration. The ABTS radical-cation decolorization was above 80% at the $100{\mu}g/ml$ concentration in all the extracts of various medicinal plants. The antioxidant protection factor (PF) of the Melia azedarach L. extracts was found to be $1.65{\pm}0.40$ PF in the water extracts at the $100{\mu}g/ml$ concentration, and was higher than those of the other medicinal-plant extracts. The TBAR inhibition rates of all the medicinal-plant extracts, except Asparagus cochinchinensis Merr., were above 85% at the $100{\mu}g/ml$ concentration. These results confirmed that the various oriental medicinal plants (Sanguisorba officinalis Linn., Citrus unshiu Markovich, Melia azedarach L., Asparagus cochinchinensis Merr., Citrus unshiu S., Polygonum aviculare L., and Leonurus sibiricus L.) that were included in this study are useful functional-food sources.

• Korean Journal of Plant Resources
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• v.21 no.3
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• pp.196-203
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• 2008

Phytotoxicity, antioxidant activity, and cytotoxicity of the aqueous or methanol extracts from the young sprouts of the six Compositae medicinal plants were determined. Aqueous leachates at 40g dry tissue $L^{-1}$ (g $L^{-1}$) Cirsium japonicum and Aster yomena showed the highest inhibitory effect on alfalfa (Medicago sativa L.). Total phenolic content showed the highest amount in methanol extracts from Ixeris dentata, and followed by A. yomena, and Cephalonoplos segetum. Methanol extracts of C. segetum and I. dentata at 25${\mu}g$ m$L^{-1}$ exhibited the highest DPPH radical scavenging activity by 87.2, and 52.8%, respectively. By means of HPLC analysis, MeOH extracts of C. segetum had the highest amount of antioxidant chlorogenic acid. Based on MTT assay, the methanol extracts from Y. sonchifolia ($IC_{50}$ = 65.7${\mu}g$ $mL^{-1}$) showed the highest cytotoxicity against Calu-6. These results suggest that plant extracts had a dose-dependent biological potentials including phytotoxicity, antioxidant activity, and anticancer activity, and that their activities exhibited differently depending on plant species.

• The Korean Journal of Mycology
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• v.18 no.2
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• pp.102-108
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• 1990

In order to find out the effect of medicinal plant extracts on germination of zoosporan-gium and mycelium growth of Pythium ultimum, this study was carried out. Among 28 species in 16 families of plants tested, plant extracts from 9 species were strongly inhibitory to zoosporan-gium germination of P. ultimum. Plant extracts from 3 species were strongly inhibitory to mycellium growth of P. ultimum. Especially, Paeonia suffruticosa was strongly inhibitory. P. suffruticosa was shown a strong control effect on damping-off of sesame by P. ultimum sesame, but no effect on cucumber. Seed germination of sesame and cucumber was shown phyto-alexin by extract of Phytolacca esculenta.

• Korean Journal Plant Pathology
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• v.13 no.1
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• pp.57-62
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• 1997

This experiment was conducted to test the control effect of methanol extracts of 10 medicinal plants on apple storage diseases caused by Botryosphaeria berengeriana, Glomerella cingulata and Penicillium expansum. Out of the 10 medicinal plants, methanol extracts of Coptis japonica and Anemarrhena asphodeloides inhibited effectively the mycelial growth of B. berengeriana, G. cingulata and P. expansum in vitro, for which the inhibition ratios of the two plant extracts were 100.0% and 89.3%, 73.7% and 94.1%, and 100.0% and 51.6%, respectively. Spore germination of the three fungi was inhibited 100% only by C. japonica extract, but only P. expansum was inhibited 100% by A. asphodeloides extract. No lesion was formed y the fungi at 5$^{\circ}C$ up to 2 weeks after inoculation. Lesion sizes produced by the three fungi at the temperature ranges of 1$0^{\circ}C$ to $25^{\circ}C$ and infection of B. berengeriana and G. cingulata were inhibited by C. japonica extract, but not by A. asphodeloides extract, while no lesion was formed by the fungi at 5$^{\circ}C$. Infections of the fungi on apples were somewhat stimulated by A. asphodeloides extract.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.980-981
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• 2008

This study was carried out to research antimicrobial agents from medicinal plants, Lonicera japonica, Pinellia ternata, Dictamnus albus, Cryptotympana pustulata, Pinus densiflora, Bupleurum falcatum, Forsythia saxatilis, Castanea crenata, Hovenia dulcis, Prunus sargentii. The ethanol extracts of 10 medicinal plants were tested for the antimicrobial activity against Streptococcus mutans. The extracts of Pinus densiflora showed significant antimicrobial activity against Streptococcus mutans. These results suggested that the extract from Pinus densiflora could be a candidate for new antimicrobial agents against Streptococcus mutans.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.547-553
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• 2018

This study was conducted to investigate the effect of branch extracts of Vaccinium oldhamii (VOB) on melanin synthesis in B16F10 cells. VOB promoted melanin production in absence or presence of ${\alpha}$-melanocyte-stimulating hormone (${\alpha}-MSH$) in B16F10 cells. However, VOB did not affect the expression of tyrosinase and TRP-1 associated with melanin synthesis at the mRNA and protein levels in B16F10. But, VOB decreased TRP-2 protein level and induced tyrosinase activation in B16F10 cells. Inhibition of tyrosinase activity and tyrosinase knockdown attenuated VOB-mediated melanin synthesis. In conclusion, VOB may stimulate melanin synthesis through activating tyrosinase activity.

• Natural Product Sciences
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• v.29 no.2
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• pp.98-103
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• 2023

Sphaeranthus africanus is commonly used as a traditional remedy for sore throats and pain treatment in Vietnam. The aerial parts have been studied for its anti-inflammatory and anti-proliferative properties. However, the antioxidant and antidiabetic potential of the plant has not been explored. In this work, hydrophilic extracts of the plant's aerial parts were prepared in order to investigate its antioxidant and anti-diabetic properties. Also, the cytotoxicity of the root was evaluated and compared to that of the aerial parts. All of the extracts inhibited lipid peroxidation with IC₅₀ values ranging from 2.05 to 3.56 ㎍/mL, indicating substantial antioxidant activity. At an IC₅₀ value of 4.80 ㎍/mL, the 50% ethanol extract exhibited the most potent inhibition of α-glucosidase. The cytotoxic activity of root extracts is 2 to 5-fold less than that of the aerial parts. Nevertheless, dichloromethane and ethyl acetate extracts of the root demonstrated a selective effect on leukemia cells, with no harm towards the normal HEK-293 cell line. This work provides a scientific support for the antioxidant and antidiabetic activity of the plant. Hence, it may find a promising material for the development of novel antioxidant and antidiabetic agents. More research can be conducted on the phytochemistry and anticancer activities of the plant's root.