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

• Toxicological Research
• /
• v.7 no.2
• /
• pp.151-155
• /
• 1991

Thirty six crude drug samples have been prepared from different parts of twenty five plants belonging to different families, and antimutangenic activities were studied by using SOS chromotest (E. coli PQ 37). The following crude extracts of PNG medicinal plants which had a appreciable antimutagenic activity against mitomycin C were: Artocarpus communis (stem bark), Cycas circinalis (leaves), Merremia peltata (leaves), Intsia palembanica (leaves), Annona muricata (stem bark), and Artocarpus altilis (root bark).

• Advances in Traditional Medicine
• /
• v.3 no.4
• /
• pp.205-211
• /
• 2003

Stem bark of Cinchona sp. (Rubiaceae) is one of the well known drugs for its therapeutic values in traditional as well as modern medicine. Even though a lot of work has been carried out on quinoline alkaloids of Cinchona, its phenolic constituents received very little attention. In the present study, we evaluated antioxidant properties of C. officinalis stem bark methanolic extract and water extract containing phenolic compounds (total phenolics 21.37, 5.18% w/w respectively in the two extracts) in different in vitro and ex vivo models viz., antiradical activity by DPPH reduction, superoxide radical scavenging activity in riboflavin/light/NBT system, nitric oxide radical scavenging activity in sodium nitroprusside/Greiss reagent system and inhibition of lipid peroxidation induced by iron-ADP-ascorbate in liver homogenate and haemolysis of erythrocytes induced by phenylhydrazine in erythrocyte membrane stabilization study. Both the extracts exhibited very good antioxidant activity in all the models tested. The phenolic compounds including tannins present in the stem bark seem to offer protection from the oxidative damage.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.6
• /
• pp.126-134
• /
• 2007

This study reviewed the application of an extract from Kalopanax pictus stem bark and root bark as natural antioxidants. To investigate the effect on cell toxic level against transformed mouse fibroblast L929 in formula added with various extracts from Kalopanax pictus stem bark and root bark, this experiment was carried out by in vitro cytotoxicity method. Using DCFA-DA method, oxidative stress in cell was measured with other antioxidant activity methods including DPPH assay and NBT assay. Active oxygen inhibition rate for root bark insoluble hot water extracts showed the highest with 57.9% for 15 min treatment. In DPPH and NBT test, antioxidant activities of methanol extract from stem bark and insoluble hot water extract from stem bark were 96% (at 0.1%) and 95% (at 0.5%), respectively.

• 보존과학연구
• /
• s.28
• /
• pp.59-73
• /
• 2007

Wooden artifacts are biologically damaged by animals, insects, and micro-organisms. We focused on the evaluation of the antifungal and insecticidal activities of tree extracts to control deterioration of wooden cultural properties. 12 kinds of methanol extracts from 9 species of tree were investigated for their biocidal activities against two micro-organisms and two spices of insect. Most tree extracts showed fungicidal activities to Tyromyces palustris and Trametes versicolor. Among 12 different tree extracts, the strongest antifungal activity against T.palustris and T.versicolor was observed from the extracts of Pinus densiflora stem-bark extract and Pinus koraiensis leaf extracts. However, in the insecticidal activity test, Pinus densiflora stem-bark extracts against termite was relatively effective. Chemical compositions of methanol extracts were analyzed by gas chromatography/mass spectrometry. As a result, it was confirmed that development of biocide based on the natural extracts can be expected to conservate of wooden cultural properties.

• Applied Biological Chemistry
• /
• v.43 no.2
• /
• pp.148-152
• /
• 2000

The antioxidative activities of water-soluble extracts from leaves and stem bark of Morus alba and Cudrania tricuspidata were compared in vitro experimental models. Antioxidative activities were measured by inhibition activity against lipid peroxidation of mouse liver microsome, and they were showed in the following order; stem bark of C. tricuspidata(53%)>stem bark of M. alba(43%)>leaves of C. tricuspidata(38%)>leaves of M. alba(43%). In antioxidative activities determined by thiocyanate method and TBA method, the water-soluble extract of stem bark of C. tricuspidata showed the highest antioxidative activity. The water-soluble extracts of leaves were slightly stronger than other extracts in DPPH$({\alpha},{\alpha}'-diphenyl-{\beta}-picrylhydrazyl)$ method. The concentrations of total polyphenolic compound from water-soluble extracts of leaves and stem bark of M. alba and C. tricuspidata were 1.32%, 1.28%, 1.34% and 1.30% respectively. In these results, the water-soluble extract of stem bark from Cudrania tricuspidata showed the highest antioxidative activity.

• Advances in Traditional Medicine
• /
• v.3 no.1
• /
• pp.1-7
• /
• 2003

Some Korean plants were found to inhibit HIV-1 protease activity. The extracts of Acanthopanax koreanum (stem bark), Berchemia berchemiaefolia (stem), Berchemia berchemiaefolia (bark), Distylium racemosum (leaves), Distylium racemosum (stem), Lindera erythrocarpa (leaves), Physalis alkekengi var. francheti (root), Platycarya strobilacea (stem), Rodiola rosea (root), Rosa davurica (stem), Syringa dilatata (leaves), Viburnum awabuki (stem) and Viburnum awabuki (leaves) showed significant inhibitory effect against HIV-1 protease. Camelliatannin H from Camellia japonica and uvaol from Cratagus pinatrifida were potent active inhibitors of HIV-1 protease with $IC_{50}$ values of $0.9\;{\mu}M$ and $5.5\;{\mu}M$, respectively. The cure and prevention of AIDS have been a global challenge since it was discovered in the ealy 1980s. However, the development of anti-HIV agent that can effectively treat or prevent this disease are still demanded.

• BMB Reports
• /
• v.34 no.5
• /
• pp.463-471
• /
• 2001

The bark of Ulmus darvidiana var. japonica Nakai (UDN) has been used for a long time to cure inflammation in oriental medicine. In the present study, two types of extracts, Ulmus water-eluted fraction (UWF) and Ulmus ethanol-eluted fraction (UEF), were prepared from the UDN stem bark, and employed to test the extracts to see if they had anti-oxidative properties against hydroxyl radicals that could alter immune reactivity in mouse immune cells. Deoxyribose assay, DNA nicking assay, and glucose/glucose oxidase assay showed that both fractions had scavenging activity against oxygen free radicals at 50 mg/ml. In addition, hydroxyl radical-mediated apoptosis in mouse thymocytes was not protected by UEF treatment, but the apoptosis was protected by UWF at the same concentration. DNA synthesis and cytokine production that were induced in splenocytes by mitogens (Concanavalin A and lipopolysaccharide) were reduced by the addition of both fractions. These results indicate that both extracts that were prepared from the UDN stem bark have anti-oxidative activities, anti-apoptotic effects, and inhibitory effects on DNA synthesis and cytokine production in mouse immune cell cultures.

• Korean Journal of Pharmacognosy
• /
• v.29 no.3
• /
• pp.163-168
• /
• 1998

Seven antioxidative compounds were isolated from chloroform and ethyl acetate extracts of the stem bark of Eucalyptus globulus (Myrtaceae). They were identified as rhamnazin (1), rhamnetin (2), naringenin (3), eriodictyol (4), quercetin (5), taxifolin (6) and dihydrokaempferol-3-rhamnoside (7) on the basis of various spectroscopic analyses. These compounds inhibited lipid peroxidation with $IC_{50}$ values of 0.08-30 ${\mu}g/ml$.

• Natural Product Sciences
• /
• v.15 no.4
• /
• pp.208-212
• /
• 2009

The heartwood of Rhus verniciflua Stokes (Anacardiaceae) is widely used for a medicinal plant to treat diabetes mellitus and lingering intoxication in the folkloric society of Korea, while the stem bark has been traditionally used to treat menstrual disorder and helminthiasis. We previously reported that a flavonoid, fustin, isolated from the heartwood of R. verniciflua is effective in Alzheimer‘s disease and rheumatoid arthritis. To explore the possibility to produce more flavonoid-rich fraction from this plant, the MeOH extracts from the plant parts of stem bark, outer heartwood, and inner heartwood were quantitatively analyzed by HPLC. Phenolic or flavonoid compounds (chlorogenic acid, caffeic acid, p-coumaric acid, sulfuretin, fustin, fisetin, luteolin and astragalin) were detectable in the HPLC chromatogram. The orange-colored inner heartwood was found to contain the highest levels of fustin (16.96 mg/g) and sulfuretin (2.22 mg/g). Moreover, the inner heartwood accumulated fustin and sulfuretin at least 4-fold higher level as compared to the stem bark and outer heartwood. The levels of total phenolic compounds positively correlated with the extents of antioxidant properties. Therefore, the inner heartwood of R. verniciflua could be used to increase fustin concentration of the extract which is capable of treating Alzheimer‘s disease and rheumatoid arthritis.