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1.
The n-hexane and ethyl acetate extracts of whole plants of Dysophylla stellata significantly inhibited edema when applied topically at doses of 0.5 and 1 mg/ear in TPA-induced ear edema assay in mice. Further, both the extracts were evaluated for COX-1 and COX-2 inhibitory activities and showed 85.42 and 57.38%; and 71.79 and 89.27% inhibition at 50 µg/ml, respectively. Chromones (1 and 2) present in these extracts could be responsible for their COX-1 and COX-2 inhibitory and anti-inflammatory activities. The ethyl acetate extract showed antioxidant activity in DPPH and ABTS radical scavenging assay where as n-hexane extract found to be inactive.  相似文献   

2.
Three new flavones named 5-carboxymethyl-4′,7-dihydroxyflavone (1), its ethyl ester (2) and butyl ester (3) were isolated from the herb Selaginella moellendorffii Hieron., together with ten known compounds. Their structures were elucidated on the basis of spectroscopic and chemical analysis. Selected compounds were evaluated for their anti-HBV and cytotoxic activity. Among them, compounds 2 and 3 displayed inhibitory activity in vitro on hepatitis B virus (HBV) surface antigen (HBsAg) secretion of the Hep G2.2.15 cell line with IC50 values of 0.17 mg/ml and 0.46 mg/ml, and on HBV e antigen (HBeAg) secretion with IC50 values of 0.42 mg/ml and 0.42 mg/ml, respectively. Compounds 7, 8, 10 and 12 exhibited selective cytotoxicity against the three human cancer cell lines tested.  相似文献   

3.
The standardized EtOAc, MeOH and 70% EtOH extracts of Tridax procumbens aerial parts showed significant inhibition of rat paw edema at a medium dose of 200 mg/kg and the EtOAC extract was the most active. These extracts were standardized by HPLC with the help of chemical markers. Further, the extracts were evaluated for COX-1 and COX-2 inhibitory activity and EtOAc extract exhibited the highest inhibition of COX-1 and COX-2 at 50 μg/mL. Cent aurein, centaureidin and bergenin were isolated as COX-1 and COX-2 inhibitory principles from the EtOAc extract. The extracts also exhibited antioxidant activity against DPPH and ABTS free radicals. The anti-inflammatory activity of T. procumbens aerial parts could be at least in part due to COX-1, COX-2 enzyme inhibition and free radical-scavenging activities which may be attributed to the presence of flavonoids and other polyphenols in the extracts.  相似文献   

4.
Antioxidants have been considered as a useful remedy in diabetes therapeutics, and thus, herbal medicines with antioxidant properties may play major role in treating diabetes. In this report, we performed a comparative study using American ginseng and Scutellaria baicalensis to test whether the anti-diabetic effect of American ginseng is associated with its antioxidant activity. We used a simple water extraction procedure to prepare American ginseng root extract (AGE) and S. baicalensis extract (SbE), and utilized these two antioxidant herbs to evaluate their anti-diabetic effect in obese diabetic ob/ob mice. HPLC analysis was used to identify major constituents in the AGE and SbE. After 12 days of daily intraperitoneal injection, AGE at 300 mg/kg showed significant effects on fasting blood glucose levels (P < 0.01) and glucose tolerance test (P < 0.01) compared to vehicle-treated mice. Animal body weights also reduced significantly after 12-day treatment (P < 0.01). However, SbE, a very strong antioxidant extract, administered at 5–50 mg/kg (based on our previous studies without adverse events) for 12 days did not show any significant effects on blood glucose and body weight changes. No effects were shown when baicalein, an effective antioxidant constituent in SbE, was administered at 1–5 mg/kg. It appears that the anti-diabetic effect of American ginseng may not be linked to its antioxidant actions. The mechanisms of American ginseng's effects on reducing high blood glucose levels and body weight remain to be investigated in future experiments.  相似文献   

5.
Tribulus terrestris L. (Zygophyllaceae) is one of the highly traded raw drugs and also used as a stimulative food additive in Europe and USA. While, Ayurvedic Pharmacopoeia of India recognizes T. terrestris as Goksura, Tribulus lanuginosus and T. subramanyamii are also traded by the same name raising issues of quality control. The nuclear ribosomal RNA genes and ITS (internal transcribed spacer) sequence were used to develop species-specific DNA markers. The species-specific markers efficiently amplified 295 bp for T. terrestris (TT1F and TT1R), 300 bp for T. lanuginosus (TL1F and TL1R) and 214 bp for T. subramanyamii (TS1F and TS1R). These DNA markers can be used to distinguish T. terrestris from its adulterants.  相似文献   

6.
The present study reports the potential antinociceptive, anti-inflammatory and hepatoprotective activities of lycorine from Sternbergia fischeriana (Herbert) Rupr. (Amaryllidaceae). Lycorine was evaluated on mice by using acetic-acid induced writhing and tail-flick tests. Lycorine exhibited stronger inhibition than aspirin in acetic-acid induced abdominal stretching at 1.0 mg/kg dose. Lycorine also showed antinociceptive activity at 1.0 mg/kg dose in tail-flick test. The anti-inflammatory activity of lycorine was not found to be significant at dose of 0.5 mg/kg. However, at doses of 1.0 mg/kg and 1.5 mg/kg, i.p. showed a significant reduction with 53.45% and 36.42%, respectively in rat paw oedema induced by carrageenan against the reference anti-inflammatory drug indomethacin (3 mg/kg, i.p.) (95.70%). The ED50 of lycorine was determined as 0.514 mg/kg. Hepatoprotective activity of lycorine on carbon tetrachloride (CCl4) induced acute liver toxicity following biochemical parameters were also evaluated. Rats were treated with lycorine at doses of 1.0 mg/kg and 2.0 mg/kg, i.p. Results of biochemical tests were confirmed by histopathological examination. Lycorine exhibited significant hepatoprotective effect at dose of 2.0 mg/kg i.p. dose.  相似文献   

7.
We tested the effects of species and spacing of nurse trees on the growth of Hopea odorata, a dipterocarp tree indigenous to Southeast Asia, in a two-storied forest management system in northeast Thailand. Eucalyptus camaldulensis, Acacia auriculiformis, and Senna siamea were planted as nurse trees in 1987 at spacings of 4 m × 8 m, 2 m × 8 m, 4 m × 4 m, and 2 m × 4 m in the Sakaerat Silvicultural Research Station of the Royal Forest Department, Thailand. Seedlings of H. odorata were planted in the nurse tree stands at a uniform spacing of 4 m × 4 m and in control plots (no nurse trees) in 1990. Stem numbers of some nurse trees were thinned by half in 1994. The stem diameter and height of all trees were measured annually until 1995 and again in 2007. The mean annual increment (MAI) in volume was estimated as 8.2–10.1 m3 ha−1 year−1 for E. camaldulensis and 0.9–1.2 m3 ha−1 year−1 for S. siamea, smaller than reported elsewhere. This suggests that the site properties were not suitable for them. The MAI of A. auriculiformis was 7.9–9.8 m3 ha−1 year−1, within the reported range. Survival rates of H. odorata in the S. siamea stands and the control plots decreased rapidly during the first 2 years but then stayed constant from 1992. In contrast, survival rates of H. odorata in the E. camaldulensis and A. auriculiformis stands were initially high (>70%), but then decreased after 1995. Stem diameter, tree height, and stand basal area of H. odorata were large in both the S. siamea stands and the control plots from then. The growth of H. odorata was largest in the 2 m × 8 m S. siamea stands. In contrast, it was restricted in the E. camaldulensis and A. auriculiformis stands owing to strong shading by their canopies. Thinning by 50% tended to facilitate the growth of H. odorata temporarily in the E. camaldulensis and A. auriculiformis stands. The stand basal areas of nurse trees and of H. odorata showed a trade-off. These results suggest that the growth of H. odorata was maximized in the S. siamea stands. We assume, however, that the growth of H. odorata could be improved even in the E. camaldulensis and A. auriculiformis stands by frequent or heavy thinning.  相似文献   

8.
Species richness and species composition of ectomycorrhizal (EM) fungi were compared among rehabilitated mine sites and unmined jarrah forest in southwest Western Australia. Species richness, measured in 50 m × 50 m plots, was high. In the wetter, western region, mean species richness per plot in 16-year-old rehabilitated mine sites (63.7 ± 2.5, n = 3) was similar to that of unmined jarrah forest (63.6 ± 9.6, n = 9). In the drier, eastern region, species richness in 12-year-old rehabilitated mine sites (40.3 ± 2.1, n = 3) approached that of nearby forest (52.4 ± 9.3, n = 9). Species composition was analysed by detrended correspondence analysis. Rehabilitated sites of similar age clustered together in the analysis and species composition was closer to the native jarrah forest in the older rehabilitated plots. In unmined forest, species composition of fungal communities in the wetter, western region was different from communities in the drier, eastern region.  相似文献   

9.
Oxidative damage is an established outcome of chronic stress. Thus, the present study was designed to investigate the modulatory role of ethanolic extract of Evolvulus alsinoides (EA) in terms of oxidative alterations at peripheral and central level in rats subjected to chronic unpredictable stress (CUS). CUS exposure for 7 days reduced Cu, Zn superoxide dismutase and catalase activity with increase in glutathione peroxidase activity and lipid peroxidation, while decrease in reduced glutathione level in blood plasma, frontal cortex and hippocampus regions of brain. Oral administration of EA extract at 200 mg/kg p.o. normalized these stress induced oxidative alterations with an efficacy similar to that of melatonin. Further, EA extract was taken up for detailed chemical investigation. Two new flavonol-4′-glycoside, kaempferol 4′-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (3) and kaempferol 4′-O-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside (5) were isolated, along with eight known compounds (1, 2, 4 and 610). The structures of new compounds were established by detailed spectroscopic studies, while known compounds were characterized by direct comparison of their reported NMR data. All these compounds were evaluated for their in vitro antioxidant activity. Compounds 3, 5, 9 and 10 at 100 and 200 μg/ml showed significant in vitro antioxidant activity. Therefore, EA may hold great potential in preventing clinical deterioration in stress induced oxidative load and related disorders.  相似文献   

10.
The anti-inflammatory and analgesic effects of theacrine (1, 3, 7, 9-tetramethyluric acid), a purine alkaloid which is abundantly present in Camellia kucha, were investigated. Xylene-induced ear edema, acetic acid-induced vascular permeability and λ-carrageenan-induced paw edema were used to investigate anti-inflammatory activity, and acetic acid-induced writhing and hot-plate tests were used to determine analgesic effect. Oral administration of theacrine (8–32 mg/kg) induced dose-related anti-inflammatory and analgesic effects. On the other hand, oral caffeine administration (8–32 mg/kg) did not show an inhibitory effect on the inhibition of inflammatory response or cause analgesia. Additionally, the result of the acute toxicity test showed that the LD50 of theacrine was 810.6 mg/kg (769.5–858.0 mg/kg). The data obtained suggest theacrine possessed analgesic and anti-inflammatory activities.  相似文献   

11.
Aster flaccidus bge has been used as traditional medicine in northwestern China. Two new phenylpropanoids (12) including one lignan: (7′R, 8S)-9′-lariciresinol-(α-methyl)-butanoate (1), 5,9-dimethoxyl-7-(α-methyl)-butanoxyl-phenyl-2E-propenol-(α-methyl)-butanoate (2) isolated from the chloroform extract of the root of Aster flaccidus bge were identified by means of extensive spectroscopic studies: 1D and 2D NMR spectra as well as HRMS analysis. They have not obvious anti-HIV-1 therapeutic activity (TI = 1.0–1.1) compared with AZT (TI = 55,556) as the result of the determination of their in vitro anti-HIV-1 activity while compound 2 displays strong antitumor activity against BEL 7402 (human liver carcinoma) with cisplatin as a positive control and the effect increases with the measuring-time going on (24 h, IC50: 106.67 ± 8.47 µM — 72 h, IC50: 50.51 ± 6.11 µM).  相似文献   

12.
The chloroform and ethyl acetate extract (100 mg/kg) of Caesalpinia volkensii H. exhibited significant (P ≤ 0.05) antinociceptive activities using hot plate and writhing tests in mice while the later showed antiplasmodial activity (IC50 0.23 ± 0.07 and 4.39 ± 2.49 μg/ml) against chloroquine sensitive (D6) and chloroquine-resistant (W2), respectively. Two new furanoditerpenes [rel. 1β,5α-dihydroxyvoucapane (1) and rel. 1β,6β-dihydroxyvoucapane; 19β-methyl ester (2)] together with seven known compounds [voucapane (3), voucapan-5-ol (4), deoxycaesaldekarin C (5), caesaldekarin C (6), 5-hydroxyvinhaticoic acid (7), triacontanyl-(E)-ferulate (8), triacontanyl-(E)-caffaete (9) and 30′-hydroxytriacontanyl-(E)-ferulate (10)] were isolated from the two extracts. The administration of 3, 4, 5 and 6 (100 mg/kg i.p) caused a significant (P ≤ 0.05) reduction in the number of writhing episodes induced by acetic acid and (P ≤ 0.01) increased pain latency threshold in hot-plate test compared to control. However, the pure compounds indicated relatively (P ≤ 0.05) low antiplasmodial activity. The phytochemical constituents from the root bark of C. volkensii had better analgesic properties than antimalarial properties, justifying the use of the plant root bark as a remedy for pain.  相似文献   

13.
This study examined the analgesic and anti-inflammatory actions of cis-mulberroside A isolated from Ramulus mori in several models of inflammatory pain in mice. Cis-mulberroside A (25 and 50 mg/kg) given by p.o. route 30 min before challenge produced a dose-dependent inhibition of the acetic acid-induced pain and Evans blue leakage in mice. In addition, this compound exhibited significant systemic anti-inflammatory activity in carrageenan-induced mouse paw edema in a concentration-related manner (33.1–68.5% inhibition), and similar results were achieved in formalin test. Suppressive effects of cis-mulberroside A on the production of NO and expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated macrophages were also assessed. Collectively, cis-mulberroside A showed high analgesic and anti-inflammatory activities. The above results will be the supporting evidence for the potential anti-rheumatoid activity of R.mori in Chinese traditional medicine.  相似文献   

14.
Three new diarylheptanoids, together with ten known ones, were isolated from the ethanol extract from the rhizomes of Alpinia officinarum Hance. The structural identification of these compounds was mainly achieved by spectroscopic methods. The new compounds were elucidated as 7-(4″, 5″-dihydroxy-3″-methoxyphenyl)-1-phenyl -4-heptene-3-one (1), 1, 7-diphenyl-5-heptene-3-one (2) and 4-phenethyl-1, 7-diphenyl -1-heptene-3, 5-dione (3), respectively. All of the compounds showed antibacterial activity against Helicobactor pylori. Especially, the three new compounds showed strong antibacterial activity against Hp-Sydney strain 1 with the MIC values of 9–12 μg/mL, and against Hp-F44 with the MIC values of 25–30 μg/mL.  相似文献   

15.
Tropical montane cloud forest has been undergoing a drastic reduction because of its widespread conversion to pastures. Once these forests have been cleared exotic grasses are deliberately introduced for forage production. Exotic grass species commonly form monodominant stands and produce more biomass than native grass species, resulting in the inhibition of secondary succession and tree regeneration. The purpose of this study was to assess the effect of native vs. exotic grass species on the early establishment of two native tree seedlings (Mexican alder, Alnus acuminata and Jalapa oak, Quercus xalapensis) on an abandoned farm in central Veracruz, Mexico. Seedling survival and growth were monitored (over 46 weeks) in relation to grass cover and height, and available photosynthetic active radiation (PAR). More seedlings survived in the presence of the native grass Panicum glutinosum than those growing with the exotic grass Cynodon plectostachyus (92% vs. 48%). The causes of seedling mortality varied between species; Q. xalapensis was affected by herbivory by voles but mainly in the exotic grass-dominated stands, whereas A. acuminata seedlings died due to competition with the exotic grass. A. acuminata seedlings increased more in height in the exotic grass-dominated stands (102 ± 7.8 cm) compared to native grass-dominated stands (51 ± 4.7 cm). Grass layer height, cover and available PAR were correlated (Pearson; p < 0.05). In the exotic grass dominated plots, grass layer height was correlated with the relative height growth rates of Q. xalapensis (Pearson; p < 0.05). These results indicate that the exotic grass may be affecting tree regeneration directly (grass competition) and indirectly (higher herbivory). Passive restoration may occur once P. glutinosum dominated pastures are abandoned. However, when C. plectostachyus dominates, introduction of early and mid successional tree seedlings protected against vole damage is needed.  相似文献   

16.
Two new benzofuran derivatives, 2-(4′-hydroxybenzyl)-5,6-methylenedioxy-benzofuran () and 2-(4′-hydroxybenzoyl)-5,6-methylenedioxy-benzofuran (), along with 8 known compounds were isolated from 60% EtOH extract of the fibrous roots of Liriope spicata var. prolifera. Their structures were elucidated on the basis of extensive spectroscopic analysis. In an in vitro bioactive assay, the two new benzofuran derivatives showed anti-inflammatory activity. Compounds 1 and 2 exhibited significant inhibitory activity against neutrophil respiratory burst stimulated by phorbol 12-myristate 13-acetate (PMA) with IC50 value of 4.15 ± 0.07 and 5.96 ± 0.37 μM, respectively.  相似文献   

17.
The Warner Mountains of northeastern California on the Modoc National Forest experienced a high incidence of tree mortality (2001–2007) that was associated with drought and bark beetle (Coleoptera: Curculionidae, Scolytinae) attack. Various silvicultural thinning treatments were implemented prior to this period of tree mortality to reduce stand density and increase residual tree growth and vigor. Our study: (1) compared bark beetle-caused conifer mortality in forested areas thinned from 1985 to 1998 to similar, non-thinned areas and (2) identified site, stand and individual tree characteristics associated with conifer mortality. We sampled ponderosa pine (Pinus ponderosa var ponderosa Dougl. ex Laws.) and Jeffrey pine (Pinus jeffreyi Grev. and Balf.) trees in pre-commercially thinned and non-thinned plantations and ponderosa pine and white fir (Abies concolor var lowiana Gordon) in mixed conifer forests that were commercially thinned, salvage-thinned, and non-thinned. Clusters of five plots (1/50th ha) and four transects (20.1 × 100.6 m) were sampled to estimate stand, site and tree mortality characteristics. A total of 20 pre-commercially thinned and 13 non-thinned plantation plot clusters as well as 20 commercially thinned, 20 salvage-thinned and 20 non-thinned mixed conifer plot clusters were established. Plantation and mixed conifer data were analyzed separately. In ponderosa pine plantations, mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB) caused greater density of mortality (trees ha−1 killed) in non-thinned (median 16.1 trees ha−1) compared to the pre-commercially thinned (1.2 trees ha−1) stands. Percent mortality (trees ha−1 killed/trees ha−1 host available) was less in the pre-commercially thinned (median 0.5%) compared to the non-thinned (5.0%) plantation stands. In mixed conifer areas, fir engraver beetles (Scolytus ventralis LeConte) (FEN) caused greater density of white fir mortality in non-thinned (least square mean 44.5 trees ha−1) compared to the commercially thinned (23.8 trees ha−1) and salvage-thinned stands (16.4 trees ha−1). Percent mortality did not differ between commercially thinned (least square mean 12.6%), salvage-thinned (11.0%), and non-thinned (13.1%) mixed conifer stands. Thus, FEN-caused mortality occurred in direct proportion to the density of available white fir. In plantations, density of MPB-caused mortality was associated with treatment and tree density of all species. In mixed conifer areas, density of FEN-caused mortality had a positive association with white fir density and a curvilinear association with elevation.  相似文献   

18.
The potential benefits of species mixture were investigated using pair-wise comparisons of four timber tree species in northern Viet Nam. Chukrasia tabularis, Canarium album, Michelia mediocris and Eucalyptus urophylla were grown in monocultures and in pair-wise mixtures. The trial was established as a randomized block design with each treatment replicated four times. Volume production gain or loss in mixtures was assessed by calculating a mixture index, which is defined as Relative Yield Total (RYT). At age 48 months, the trial indicated mixed performance with both positive and negative impacts of growing some species in mixtures compared to monocultures. The largest gain was shown in the mixture of a shade-intolerant species, Chukrasia with a more shade-tolerant species, Michelia (47% gain in relative yield), and Eucalyptus with Michelia (45% gain in relative yield) at the first 38 months. The other three mixtures tested, and which were not successful (i.e. had lower relative yields) at 38 months, was the mixture of all shade-intolerant species, including Chukrasia with Canarium, Canarium with Eucalyptus and Chukrasia with Eucalyptus. This suggests that species with different shade tolerances can form complementary pair-wise mixtures, but this changed significantly (P < 0.05) over the following 10 months. At age 48 months the RYT of Chukrasia with Michelia increased by 12%, those of Michelia with Eucalyptus decreased by 20% at 48 months compared to 38 months, suggesting that Eucalyptus should be thinned at around year 5 years. Likewise, the RYT of Michelia with Canarium declined significantly by 23% at 48 months. The RYT of other tested mixtures remained almost unchanged over time.  相似文献   

19.
Eupatorium aschenbornianum is considered useful in the treatment of gastric ulcer. In the current study the validity of this practice was tested by using the experimental model of an ethanol induced gastric ulcer in rats. The results show that E. aschenbornianum had gastroprotective activity, that the hexane extract had the highest protective activity (85.65 ± 4.76%), and that encecanescin isolated from this extract was the main active gastroprotective agent. The effect elicited by encecanescin was attenuated by NG-nitro-l-arginine methyl ester, N-ethylmaleimide and indomethacin, which suggests that NO, prostaglandins and sulfydryl groups are involved in the mechanisms of gastroprotective action.  相似文献   

20.
Zhang BB  Shi K  Liao ZX  Dai Y  Zou ZH 《Fitoterapia》2011,82(6):854-860
Phytochemical investigation of the ethanol extract of Pedicularis kansuensis Maxim. led to the isolation of one new triterpenoid and two new phenylpropanoid glycosides, along with ten known compounds. Their structures were established by extensive 1D and 2D NMR, as well as other spectrum analysis. Biological evaluation of the three new compounds against Hela cell and Hep-6 cell with MIC values ranging from 9 to 20 μg/ml.  相似文献   

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