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Antioxidant Activity and Irritation Test of Extracts Obtained from Angelica dahurica
Abstract
In this study, we assessed the free radical scavenging and xanthine oxidase inhibitory activities of extracts isolated from the dried roots and stems (including leaves) of Angelica dahurica. The irritation response from these extracts was also assessed to determine potential cosmetic use. Both sources of A. dahurica extracts exhibited radical scavenging properties to different extents. The free radical scavenging potency () of the stems (including leaves) of A. dahurica was 243.33 , which is significantly lower (p
... Angelica dahurica (A. dahurica) is a commonly used herb in traditional Chinese medicine with anti-bacterial [1] , anti-oxidant [2] , anti-inflammation [3][4] , neuroprotective [5] , and analgesic effects [6] . It's often used for the treatment of common cold, skin damage with inflammation, and migraine as well as applications in skin cosmetics. ...
Angelica dahurica (A. dahurica) is a traditional Chinese medicinal plant being used in clinical practice. The present study demonstrated that A. dahurica could reduce white-fat weight in high-fat-diet hyperlipidemic mice, decrease total cholesterol and triglyceride concentrations in the livers of both high-fat-diet and Triton WR1339 induced hyperlipidemic mice, and enhance the total hepatic lipase activities of them. These findings were further supported by the results derived from the experiments with HepG2 cells in vitro. In addition, the proteins related to lipids metabolism were investigated using LC-MS/MS, indicating that genes of lipid metabolism and lipid transport were regulated by A. dhurica. The results from LC-MS/MS were further conformed by Western blot and real time PCR assays. A. dahurica could down-regulate the expression of catalase (CAT) and sterol carrier protein2 (SCP2) and up-regulate the expression of lipid metabolism related genes-lipase member C (LIPC) and peroxisome proliferator-activated receptor gamma (PPAR?). In the Triton WR1339 mouse liver and HepG2 cells in vitro, A. dahurica was able to increase the expression of LIPC and PPAR?, confirming the results from in vivo experiments. Imperatorin showed the same activity as A. dahurica, suggesting it was one of the major active ingredients of the herb. In conclusion, our work represented a first investigation demonstrating that A. dahurica was able to regulate lipid metabolism and could be developed as a novel approach to fighting against fatty liver and obesity.
... Our results suggested that almost all herbal ingredients, i.e., AD, AP, LC, NJ, PK, SC, and TC, served as scavengers of specific ROS and RNS, which was further supported by previous evidence. [17][18][19][20][21][22][23][24] To the best of our knowledge, the scavenging properties of AP against O 2 •− and of SC against OH • have not been reported elsewhere. It can be observed that, with the exception of TC, when individually assayed for their antioxidant activities and cytotoxicity, both the hydroethanolic and the water extract of each herbal ingredient in PN appeared to be less active than the polyherbal combination of PN. ...
Background
Phikud Navakot (PN), a combination of nine herbs, has been used traditionally in Thai medicinal formulas to relieve circulatory disorder. The present study aimed to compare the synergistic antioxidant efficacy and toxicity of the hydroethanolic and water extracts of PN at cellular level.
Methods
PN and its nine herbs were extracted with either 50% ethanol or water. All extracts were tested for in vitro antioxidant potential using standard antioxidant assays. Evaluation of cytotoxicity, genotoxicity, and intracellular reactive oxygen species were performed using human endothelial ECV304 cells.
Results
Antioxidant assays in cell-free systems showed that the hydroethanolic extract of PN scavenged superoxide, hydroxyl, nitric oxide radicals, and hydrogen peroxide more effectively than its water extract. Combination indices were calculated to show that the ingredients of the hydroethanolic extract acted synergistically to exhibit antioxidant activities against all tested radicals, whereas, in the case of water extract, this effect was observed only against 2,2-diphenyl-1-picrylhydrazyl, superoxide, and hydroxyl radicals. A cell-based assay also revealed that the hydroethanolic extract concentration-dependently attenuated hydrogen peroxide-induced stress more effectively than the water extract. At the antioxidant and cytotoxic concentrations of both extracts, no genotoxicity was found.
Conclusion
Our findings demonstrate that the synergistic antioxidant action of PN ameliorates endothelial stress, which may provide some clues for understanding the traditional use of PN for the treatment of circulatory disorder. Additionally, the selection of a suitable solvent for the extraction of PN herbal combination is essential for maximal efficacy and safety.
Angelica dahurica (A. dahurica) root is a famous edible medicinal herb that has been used in China for thousands of years. To date, more than 300 chemical constituents have been discovered from A. dahurica. Among these ingredients, coumarins and volatile oils are the major active compounds. Moreover, a few other compounds have also been isolated from the root of A. dahurica, such as alkaloids, phenols, sterols, benzofurans, polyacetylenes and polysaccharides. Modern pharmacological studies demonstrated that the root of A. dahurica and its active components displayed various bioactivities such as anti-inflammation, anti-tumor, anti-oxidation, analgesic activity, antiviral and anti-microbial effects, effects on the cardiovascular system, neuroprotective function, hepatoprotective activity, effects on skin diseases and so on. Based on these studies, this review focused on the research publications of A. dahurica and aimed to summarize the advances in the traditional uses, phytochemistry and pharmacology which will provide reference for the further studies and applications of A. dahurica.
Ethnopharmacological relevance:
Anti-inflammatory effects of Angelica dahurica (AD) have been reported in previous studies. In this study, we investigated the anti-inflammatory effects of AD on periodontitis.
Materials and methods:
Male Sprague-Dawley rats aged 7 weeks (n = 7) were subjected to ligature around bilateral mandibular first molars. 1 and 100mg/mL of AD were topically applied to first molars for 14 days. Histological changes were observed in gingival epithelial layer, and the thickness of the gingival epithelial layer as well as the number of epithelial cells were quantified. To investigate the mRNA expression of pro-inflammatory cytokines in gingival tissues, reverse transcriptase polymerase chain reaction was performed. To confirm the anti-inflammatory effects of AD, pro-inflammatory mediators including cytokines and NF-kB, COX-2, and iNOS were analyzed in LPS-stimulated Raw 264.7 cells.
Results:
Topical application of AD attenuated not only the thickness of epithelial layer, also the number of epithelial cells in gingival tissue. The expressions of IL-1β, IL-6, IL-8, and IFN-γ in gingiva were significantly reduced by AD treatment. Additionally, the expressions of IL-1β, IL-6, IL-8 and IFN-γ mRNA were inhibited by AD in LPS-treated RAW264.7 macrophage cells. Furthermore, AD treatment decreased LPS-induced elevation of NF-κB, COX-2 and iNOS protein levels in RAW264.7 cells.
Conclusion:
Taken together, AD application ameliorated the hyperplasia of gingival epithelial layer by down-regulating pro-inflammatory mediators. AD might have therapeutic potentials for periodontal diseases.
MicroRNAs (miRNAs) are small, endogenous, single-stranded, noncoding RNAs. Circulating miRNAs are being considered as promising disease biomarkers. Indeed, single miRNAs have been associated with a wide variety of disease conditions and can target multiple mRNAs; therefore, several miRNAs may be simultaneously involved in disease progression and development. In this study, we developed a capillary electrophoresis with dual laser-induced fluorescence (CE with dual LIF) method using two color laser excitations for simultaneous determination of multiple miRNAs. Target miRNAs were hybridized with 6-FAM- or Cy5-labeled DNA probes for simultaneous determination of multiple miRNAs at excitation wavelengths of 488 and 635nm. The hybridized miRNAs were separated using CE with dual LIF and detected within 13min at excitation wavelengths of 488 and 635nm without any interference or crosstalk. Additionally, the proposed approach was used successfully to detect and evaluate levels of several endogenous miRNAs from lung cancer cell lines. These results showed the potential of CE with dual LIF for fast, specific, simultaneous analysis of multiple miRNAs in cell extracts, biofluids, and tissues.
Ipomoea aquatica Forsk, a green leafy vegetable that is a rich source of vitamins and amino acids with many health benefits, has been explored for the isolation and identification of its bioactive compounds. Activity-guided repeated fractionation of a methanol extract on a silica gel column followed by an XAD column yielded a compound that exhibited antioxidant activity with an EC50 value of 83 ± 1.02 µg ml−1 reaction mixture. It also showed very strong lipid peroxidation-inhibitory activity in a liposome model system with an EC50 value of 72.2 ± 0.9 µg ml−1. However, it showed negligible metal-chelating activity. Based on UV, 2D nuclear magnetic resonance and gas chromatography/mass spectrometry studies, the compound was tentatively identified to be 7-O-β-D-glucopyranosyl-dihydroquercetin-3-O-α-D-glucopyranoside. This is the first report on the antioxidant properties of I aquatica leaf extracts. Copyright © 2005 Society of Chemical Industry
Antioxidant activities of ethanolic extracts of whole almond seed, brown skin, and green shell cover were evaluated using
different free radical trapping assays. Trolox equivalent antioxidant capacity assay revealed that the total antioxidant capacities
of brown skin and green shell cover extracts were 13 and 10 times greater than that of the whole seed extract at the same
extract concentration. The free radical-scavenging activity of extracts of brown skin and green shell cover also exceeded
that of the whole seed. The scavenging activity of superoxide radical by different almond extracts ranged from 76 to 97% at
100 ppm and 85 to 99% at 200 ppm. The corresponding reduction of hydrogen peroxide concentration was 59–66% (100 ppm) and
86–91% (200 ppm). The hydroxyl radical-scavenging capacities at 100 and 200 ppm were 16 and 42% for whole seed, 57 and 100%
for brown skin, and 40 and 56% for green shell extracts, respectively. A 100% scavenging activity of the 2,2-diphenyl-1-picrylhydrazyl
(DPPH) radical was observed for brown skin and green shell extracts at 100 and 200 ppm concentrations, respectively, and whole
seed extracts scavenged 21 (at 100 ppm) and 73% (at 200 ppm) of the DPPH radical.
Bioassay-guided fractionation of a hexane extract prepared from the roots of the Chinese drug Angelica dahurica (Bai Zhi) led to the isolation of the polyacetylenic natural product falcarindiol (1). The absolute stereochemistry of this compound was confirmed by careful 1H NMR analysis of its (R)- and (S)-Mosher ester derivatives as the 3(R), 8(S) isomer. Activity was tracked using a Mycobacterium fortuitum screening assay and the purified product was evaluated against multidrug-resistant and methicillin-resistant strains of Staphylococcus aureus (MRSA). The minimum inhibitory concentrations (MIC) of this metabolite ranged from 8 to 32 microg/ml highlighting the potential of the acetylene natural product class as antibiotic-lead compounds. These MIC values compare favourably with some of the newest agents in development for the treatment of MRSA infection and indicate that further evaluation of the antibiotic activity of acetylenes is warranted.
Among 288 extracts, prepared from 96 medicinal plants used in Vietnamese traditional medicine to treat gout and related symptoms, 188 demonstrated xanthine oxidase (XO) inhibitory activity at 100 microg/ml, with 46 having greater than 50% inhibition. At 50 microg/ml, 168 of the extracts were active, with 21 possessing more than 50% inhibition. At 25 microg/ml, 146 extracts exhibited inhibitory activity, with 8 showing over 50% inhibition, while 126 extracts presented activity at 10 microg/ml, with 2 having greater than 50% inhibition. The MeOH extracts of Artemisia vulgaris, Caesalpinia sappan (collected at the Seven-Mountain area), Blumea balsamifera (collected in Lam Dong province), Chrysanthemum sinense and MeOH-H(2)O extract of Tetracera scandens (Khanh Hoa province) exhibited strong XO inhibitory activity with IC(50) values less than 20 microg/ml. The most active extract was the MeOH extract of the flower of C. sinense with an IC(50) value of 5.1 microg/ml. Activity-guided fractionation of the MeOH extract led to the isolation of caffeic acid (1), luteolin (2), eriodictyol (3), and 1,5-di-O-caffeoylquinic acid (4). All these compounds showed significant XO inhibitory activity in a concentration-dependent manner, and the activity of 2 was more potent (IC(50) 1.3 microM) than the clinically used drug, allopurinol (IC(50) 2.5 microM).
The objective of the present study was to investigate the postprandial metabolism of two starches with contrasting rates of hydrolysis in vitro. Characterized using the Englyst method of in vitro starch classification, C*Set 06 598 contained predominantly rapidly digestible starch and C*Gel 04 201 contained predominantly slowly digestible starch. Each test starch, naturally enriched with 13C, was fed to ten healthy female volunteers as part of a moderate fat test meal (containing 75 g test starch and 21 g fat), in a double-blind randomized crossover design. The metabolic response to each starch was measured after an overnight fast, in an acute 6 h study, before and after 14 d of daily consumption of 75 g test starch. During each acute study, blood samples were taken at 15 min intervals for the first 2 h and at 30 min intervals for the remaining 4 h. Breath 13CO2 enrichment was measured at the same time points and indirect calorimetry was performed for 20 min every 40 min immediately before and throughout the study. Significantly more rapid, greater changes in postprandial plasma glucose, NEFA and serum insulin concentrations were observed after consumption of the rapidly digestible starch. Breath 13CO2 output over the first 3-4 h rose rapidly then began to decline following consumption of the rapidly digestible starch, but plateaued for the slowly digestible starch. The 14 d adaptation period did not affect any of the glycaemic or lipaemic variables but there was a reduction in postprandial plasminogen activator inhibitor-1 concentrations. These data confirm that starches characterized as predominantly rapidly digestible versus slowly digestible by the Englyst procedure provoke distinctly different patterns of metabolism postprandially.
Fifty-one tannins and forty-one flavonoids isolated from Oriental medicinal herbs were evaluated for their antioxidant ability with a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-generating system. The results showed that tannins and certain flavonoids are potential free-radical scavengers, and that their activity against the DPPH radical is closely associated with their chemical structure. A comparison of the two classes of compounds showed that tannins have more potential than flavonoids because almost all the tannins demonstrated significant scavenging action within a low concentration range, whereas the activity of flavonoids varied distinctively among the different compounds. An increase of galloyl groups, molecular weight, and ortho-hydroxyl structure enhanced the activity of tannins, whereas the number and position of hydroxyl groups were important features for the scavenging of free radicals by flavonoids. Moreover, it appeared that when the free hydroxyl group was methoxylated or glycosylated, the inhibitory activity was obviously decreased or even abolished.
Five new spirobifuranocoumarins, dahuribirins A-E (1-5) and two new bifuranocoumarins, dahuribirins F and G (6 and 7) were isolated from Japanese Bai Zhi (the root of Angelica dahurica BENTH. et HOOK. var. dahurica BENTH. et HOOK.) and their structures were established by chemical and spectral means.
The relationship between antioxidant activity and antimutagenicity of various tea extracts (green tea, pouchong tea, oolong tea, and black tea) was investigated. All tea extracts exhibited markedly antioxidant activity and reducing power, especially oolong tea, which inhibited 73.6% peroxidation of linoleic acid. Tea extracts exhibited a 65-75% scavenging effect on superoxide at a dose of 1 mg and 30-50% scavenging effect on hydrogen peroxide at a dose of 400 mu g. They scavenged 100% hydroxyl radical at a dosage of 4 mg except the black tea. Tea extracts also showed 50-70% scavenging effect on alpha,alpha-diphenyl-beta-picrylhydrazyl radical. The antioxidant activity and the scavenging effects on active oxygen decreased in the order semifermented tea > nonfermented tea > fermented tea. Tea extracts showed strong antimutagenic action against five indirect mutagens, i.e., AFB(1), Trp-P-1, Glu-P-1, B[a]P, and IQ, especially oolong and pouchong teas. The antioxidant effect of tea extracts was well correlated to their antimutagenicity in some cases but varied with the mutagen and antioxidative properties.
Repeated p.o. administration of myristicin and dehydrodiisoeugenol, monomeric and dimeric phenylpropanoids from mace, resulted in suppression of the lipid peroxidation in the liver of mice, which was induced by repeated i.p. injection of FeCl2–ascorbic acid–ADP. In addition, a slight decrease of SOD activity by treatment with FeCl2–ascorbic acid–ADP was recovered by administration of these compounds.
Various constituents isolated from mace inhibited the lipid peroxidation in a rat liver homogenate, which was induced by FeCl2–ascorbic acid, CCl4–NADPH or ADP–NADPH. Of these compounds, 2,3-dihydro-7-methoxy-3-methyl-2- (3,4-methylenedioxyphenyl)-5-propenylbenzofuran, myristicanol-B and 7-hydroxymyristicin strongly inhibited the FeCl2–ascorbic acid-induced lipid peroxidation by 70%–100% at 0.1–0.2 mM, and most of the constituents also strongly inhibited the ADP–NADPH-induced lipid peroxidation at the same concentrations. On the other hand, these compounds weakly inhibited the CCl4–NADPH-induced lipid peroxidation.
On the basis of the above findings, myristicin and dehydrodiisoeugenol administered to mice may inhibit the lipid peroxidation in the liver possibly by scavenging free radicals or active oxygen species directly.
The antioxidant activity and free-radical and active oxygen-scavenging activity of burdock extracts were investigated. Of
the solvents used for extraction, water yielded the greatest amount of extract that exhibited the strongest antioxidant activity.
Water extracts of burdock (WEB) and hot water extracts of burdock (HWEB) exhibited comparable and marked activity on inhibition
of linoleic acid peroxidation, indicating that heat treatment did not alter the antioxidant activity of WEB. WEB and HWEB
produced significantly lower (P<0.05) malondialdehyde (MDA) in both linoleic acid and liposome model systems than did the control. Moreover, mixtures of
tocopherol (Toc), WEB, and HWEB exhibited a remarkable synergistic antioxidant effect in a liposome system; WEB and HWEB thus
potentiated the action of Toc. Furthermore, WEB and HWEB displayed a marked inhibitory effect on lipid peroxidation of rat
liver homogenate in vitro. WEB and HWEB exhibited an 80% scavenging effect on α,α-diphenyl-β-picrylhydrazyl radical and marked reducing power, indicating
that WEB and HWEB act as primary antioxidants. Both extracts at a dose of 1.0 mg exhibited a 60.4–65.0% scavenging effect
on superoxide and an 80.5% scavenging effect on hydrogen peroxide. They also showed a marked scavenging effect on the hydroxyl
radical. These results revealed that WEB and HWEB are also active as oxygen scavengers and as secondary antioxidants. Based
on these results, termination of free-radical reactions and quenching of reactive oxygen species in burdock extracts are suggested
to be, in part, responsible for the antioxidant activity of burdock extracts.
Antioxidant, antidiabetes, and anticancer activities of fractions (water, hexane, EtOAc, and BuOH) from methanolic (MeOH)
extract of Picrasma quassioides were evaluated in vitro. Among the four fractions, BuOH fraction showed cytotoxic activity on the human stomach carcinoma cells (NCI-N87) without
cytotoxic effect on the human normal kidney cells (293) by MTT assay. Considering these results, we adapted BuOH fraction
of MeOH extract to the assessment of apoptosis by flow cytometry and mRNA expression levels of established apoptotic-related
genes on NCI-N87 cells. The experiments showed that BuOH fraction could induce apoptosis on NCI-N87 cells significantly. Take
together these results, P. quassioides showed that it could be used for potential pharmaceutical products.
The chemical components of Japanese Baizhi (Byakushi), the root of Angelica dahurica BENTH. et HOOK. (Umbelliferae), were investigated. As coumarin components, xanthotoxin, marmesin, scopoletin, anhydrobyakangelicin (isobyakangelicol), and neobyakangelicol (I) were newly isolated, in addition to byakangelicol, byakangelicin, phellopterin, oxypeucedanin, and imperatorin reported previously. The structure of I was elucidated as 5-methoxy-8-(2'-hydroxy-3'-methyl-buten-3'-yl) oxypsoralen from the following reasons. 1) Its ultraviolet (UV) spectrum resembles one of byakangelicin. 2) The elementary analysis and the mass spectrum suggest the molecular formula of C17H16O6, corresponding to an isomer of byakangelicol and anhydrobyakangelicin. 3) Its nuclear magnetic resonance (NMR) (Fig. 1) and infrared (IR) spectra show that I possesses a methyl, a hydroxyl, and a vinyl methylene groups. 4) Treatment of I with formic acid produces 5-methoxy-8-hydroxy-psoralen (II). Furthermore, alloisoimperatorin and II were isolated from the distillattion residue of petroleum-ether extract of the root.
Diploptene(1), beta-sitosterol(2), a mixture of 6'-O-(E-P-coumaroyl)-alpha-glucopyranose and 6'-O-(E-P-coumaroyl)-beta-glucopyranose(3), a mixture of 6'-O-(E-P-caffeoyl)-alpha-glucopyranose and 6'-O-(E-P-caffeoyl)-beta-glucopyranose(4), caffeic acid(5) and astragalin(6) were isolated from an ethanolic extract of the leaves of Alsophila spinulosa Hook Tryon (Cyatheaceae). The plant has been used in folk medicine for hepatitis, gout, rheumatism, and tumor and these compounds were tested for their inhibitory effect on xanthine oxidase. Caffeic acid was the most potent constituent (IC50 = 39.21 microM; Ki = 28.2 microM) and was an uncompetitive inhibitor of the enzyme with respect to the substrate xanthine.
Aging is associated with a progressive decline in the immune system and a greater susceptibility to infection. This double-blind, placebo-controlled study, examined the effect of a vitamin and trace element supplement on immune responses of healthy, noninstitutionalized elderly subjects. Forty-seven subjects aged 61-79 years were randomly assigned to receive placebo or micronutrient supplementation for one year. Thirty-five individuals completed the one-year study. Immune function was assessed before and after the period of supplementation. Cell-mediated immune function assessed by the number of T cells and subsets remained constant in the supplemented group and there was a significant increase in CD57 natural killer cells. In contrast, a significant decrease in T cells, CD4 cells, and CD4: CD8 ratio was noted in the placebo group. Supplementation with micronutrients can play a crucial role in the maintenance of normal immune function in the elderly.
The stems of Bougainvillea spectabillis Wild (Nyctaginaceae) have been used in folk medicine against hepatitis. Spinasterol, 22, 23-dihydrospinasterol and caffeic acid were isolated from the plant stems and characterized. Caffeic acid has not been previously isolated from this plant but spinasterol has been isolated from the leaves. Caffeic acid was found to be the active principle exhibiting strong inhibition of xanthine oxidase in this study (IC50 = 39.21 microM). In order to study the structure-activity relationship of the phenolics as regards xanthine oxidase inhibition, twelve naturally occurring phenolics (esculetin, scopoletin, scoparone, barbaloin, berberine chloride, sinomenine, osthole, paeonol, honokiol, magnolol, methyleugenol and 6-gingerol) were tested for their inhibitory effects on xanthine oxidase. The results showed that esculetin displayed the strongest activity (IC50 = 28.4 microM), and induced competitive inhibition of the enzyme with respect to the substrate xanthine. The apparent inhibition constant (Ki) of esculetin was 2.369 x 10(-6) M. Since xanthine oxidase serum levels are increased in hepatic and brain tumors, caffeic acid and esculetin should be tested as anti-hepatitis or/and anticancer agents.
Free radicals and antioxidants are widely discussed in the clinical and nutritional literature. Antioxidants are needed to prevent the formation and oppose the actions of reactive oxygen and nitrogen species, which are generated in vivo and cause damage to DNA, lipids, proteins, and other biomolecules. Endogenous antioxidant defenses (superoxide dismutases, H2O2-removing enzymes, metal binding proteins) are inadequate to prevent damage completely, so diet-derived antioxidants are important in maintaining health. Many dietary compounds have been suggested to be important antioxidants: The evidence for a key role of vitamins E and C is strong, but that for carotenoids and related plant pigments is weaker. Interest is also growing in the role of plant phenolics, especially flavonoids. Some antioxidants can exert prooxidant effects in vitro, but their physiological relevance is uncertain. Experimental approaches to the optimization of antioxidant nutrient intake are proposed.
The structure-activity relationship of flavonoids as inhibitors of xanthine oxidase and as scavengers of the superoxide radical, produced by the action of the enzyme xanthine oxidase, was investigated. The hydroxyl groups at C-5 and C-7 and the double bond between C-2 and C-3 were essential for a high inhibitory activity on xanthine oxidase. Flavones showed slightly higher inhibitory activity than flavonols. All flavonoid derivatives except isorhamnetin (30) were less active than the original compounds. For a high superoxide scavenging activity on the other hand, a hydroxyl group at C-3' in ring B and at C-3 were essential. According to their effect on xanthine oxidase and as superoxide scavengers, the flavonoids could be classified into six groups: superoxide scavengers without inhibitory activity on xanthine oxidase (category A), xanthine oxidase inhibitors without any additional superoxide scavenging activity (category B), xanthine oxidase inhibitors with an additional superoxide scavenging activity (category C), xanthine oxidase inhibitors with an additional pro-oxidant effect on the production of superoxide (category D), flavonoids with a marginal effect on xanthine oxidase but with a prooxidant effect on the production of superoxide (category E), and finally, flavonoids with no effect on xanthine oxidase or superoxide (category F).
In order to evaluate the pharmacological activities of Chinese medicine, nine Umbelliferae plants were selected and their restoring activity against dexamethasone-induced disorders, liver protective activity, antimicrobial activity, anti-inflammatory activity and antimutagenic activity were tested and compared. Angelica dahurica. Angelica acutiloba and Ostericum koreanum showed various activities in these tests at the dose used in this study.
One new and three known coumarins were isolated from the CHCl3 soluble fraction of Angelica dahurica stem. On the basis of spectral data, the structures of the isolated compounds were determined to be scopoletin, angelol I, angelol H and 6-[(1S), 2(R)-2, 3-dihydroxy-1-methoxy-3-methylbutyl]-7-methoxycoumarin; the latter being isolated for the first time from a plant source.
The methylene chloride extract of the root of Angelicae dahuricae showed high protective activity against 2,2'-azobis (2-aminodinopropane) dihydrochloride (AAPH)-induced cellular damage. From this extract, 11 furanocoumarins were isolated, namely oxypeucedanin hydrate, 9-hydroxy-4-methoxypsoralen, byakangelicin, pabulenol, alloisoimperatorin, neobyakangelicol, byakangelicol, oxypeucedanin, imperatorin, phellotorin and isoimperatorin, respectively. Among these 11 furanocoumarins, 9-hydroxy-4-methoxypsoralen and alloisoimperatorin displayed potent antioxidant effects against the DPPH radical and against renal epithelial cell injury by using AAPH to generate peroxyl radicals in vitro.
The antioxidant activities of four synthetic dihydropyran-2,4-diones have been established through the determination of their abilities to inhibit free radicals using DPPH(*) as the stable radical. Whilst all of the compounds exhibited high inhibition percentages, the most active member of the group was 6-phenyl-dihydropyran-2,4-dione. The antioxidant activity of the dihydropyran-2,4-diones is reported here for the first time and extends our knowledge of the range of valuable biological activities associated with this group of compounds.
A large number of polysaccharides are present in the pericarp tissues of harvested litchi fruits. A DEAE Sepharose fast-flow anion-exchange column and a Sephadex G-50 gel-permeation column were used to isolate and purify the major polysaccharides from litchi fruit pericarp tissues. Antioxidant activities of these major polysaccharide components were also evaluated. An aqueous extract of the polysaccharides from litchi fruit pericarp tissues was chromatographed on a DEAE anion-exchange column to yield two fractions. The largest amount of the polysaccharide fraction was subjected to further purification by gel filtration on Sephadex G-50. The purified product was a neutral polysaccharide, with a molecular weight of 14 kDa, comprised mainly of 65.6% mannose, 33.0% galactose and 1.4% arabinose. Analysis by Smith degradation indicated that there were 8.7% of (1-->2)-glycosidic linkages, 83.3% of (1-->3)-glycosidic linkages and 8.0% of (1-->6)-glycosidic linkages in the polysaccharide. Furthermore, different polysaccharide fractions extracted and purified from litchi fruit pericarp tissues exhibited strong antioxidant activities. Among these fractions, the purified polysaccharide had the highest antioxidant activity and should be explored as a novel potential antioxidant.
Effect of the constituents of Angelica dahurica Radix on hepatic drug metabolizing enzyme activity
- K H Shin
- O N Kim
- W S Woo
Shin KH, Kim ON, Woo WS. 1988. Effect of the constituents of Angelica dahurica Radix on hepatic drug metabolizing enzyme activity. Kor J Pharmacogn 19: 19-27.
Seven new bifuranocoumarins, dahuribirin A-G, from Japanese Bai Zhi
- Nh Wang
- K Yoshiazaki
- K Baba