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1.
3,5-O-dicaffeoyl-4-O-malonilquinic acid (1) (irbic acid) has been isolated for the first time from cell cultures of Centella asiatica and till now it has never been reported to be present in the intact plant. Evidence of its structure was obtained by spectroscopic analyses (MS/NMR). Besides 1, cell cultures produce also the known 3,5-O-dicaffeoylquinic acid, chlorogenic acid, and the triferulic acid 2 (4-O-8′/4′-O-8″-didehydrotriferulic acid). Biological activities were evaluated for compound 1, which showed to have a strong radical scavenging capacity, together with a high inhibitory activity on collagenase. This suggests a possible utilization of this substance as a topical agent to reduce the skin ageing process.  相似文献   

2.
A new antiplasmodial coumarin, 5,7-dimethoxy-8-(3'-hydroxy-3'methyl-1'-butene)-coumarin (1), has been isolated from the roots of Toddalia asiatica. This finding supports the traditional use of this plant for the treatment of malaria.  相似文献   

3.
The ethanolic extracts of the leaves and flowers of Cleome viscosa and roots of Gmelina asiatica were tested for antimicrobial activity. The two plants exhibited a broad spectrum of antimicrobial activity, particularly significative against Escherichia coli , Proteus vulgaris and Pseudomonas aeruginosa. The leaf extract of C. viscosa showed moderate activity against pathogenic fungi.  相似文献   

4.
Herath HM  deSilva S 《Fitoterapia》2000,71(6):171-724
The heart wood of Gliricidia sepium stem yielded stigmastanol glucoside (1) and 3',4'-dihydroxy-trans-cinnamic acid octacosylester 2, along with three other known constituents.  相似文献   

5.
A quantitative HPLC analysis of the major triterpenoids present in an aqueous extract of powdered neem kernels prepared in the traditional manner was undertaken. The study shows that water extracts contain all the principal triterpenoids in neem kernel though the quantities extracted are much less than in the subsequent extraction with methanol.  相似文献   

6.
Xie RJ  Yan FL  Hai GF  Hou RJ  Ding MM  Bai YX 《Fitoterapia》2011,82(4):726-730
Two new ent-kaurene diterpenoids, 15α-acetoxyl-6,11α-epoxy-6α-hydroxy-20-oxo-6,7-seco-ent-kaur-16-en-1,7-olide (1), 15α-hydroxy-20-oxo-6,7-seco-ent-kaur-16-en-1,7α(6,11α)-diolide (2), together with ten known compounds (5-14) were isolated from the leaves of Isodon rubescens. Their structures were elucidated mainly by various spectroscopic techniques and finally confirmed by single-crystal X-ray diffraction. Compounds 1, 2, 8 and 12 were evaluated for their cytotoxicities against EC-1, U87, A549, MCF-7 and Hela cell lines.  相似文献   

7.
Three new compounds, dalberpene (1), dalparvinene B (2) and dalparvone B (3), as well as 12 known compounds were isolated from the heartwood of Dalbergia parviflora. Isoflavanone 13 showed strong cytotoxicity against KB, MCF-7 and NCI-H187 cell lines with IC50 values ranging from 3.5 to 5.4 μg/mL and it was inactive against normal cells.  相似文献   

8.
Bioactive constituents from the stems of Dalbergia parviflora   总被引:1,自引:0,他引:1  
From the stems of Dalbergia parviflora, three known flavonoids, six known isoflavonoids, a new isoflavone, dalparvone (2) and a new cinnamyl derivative, dalparvinene (6) were isolated and characterized. Isoflavan 3 exhibited strong cytotoxicity against KB and NCI-H187 cell lines with IC50 values of 0.53 and 2.04 μg/ml, respectively. Compound 6 demonstrated strong cytotoxicity against NCI-H187 with an IC50 value of 1.46 μg/ml. Compounds 4 and 6 possessed moderate cytotoxicity against KB cells with IC50 values of 6.78 and 9.89 μg/ml, respectively. In addition, 2 exhibited moderate antiplasmodial activity with an IC50 value of 8.19 μg/ml.  相似文献   

9.
Extracts, fractions and constituents of Carthamus lanatus were tested for their mitogenic effect on bone marrow cells in mice. Most of the studied samples inhibited cell proliferation and only the flavonoid glycoside rutin caused increasing of mitotic activity.  相似文献   

10.
Four ligneous species from the tropical forest in the east of Madagascar, with a proven or potentially high economic value, were subject to ‘low-tech’ vegetative propagation tests from stem cuttings. The species concerned were Aphloia theiformis, Ilex mitis, Prunus africana and Ravensara aromatica. The cuttings were three-node segments of stems on which one leaf was retained. All the species proved amenable to rooting. The maximum percentage of rooting ranged from 33% for P. africana to 60% for I. mitis. Rooting success was dependant on the season of cutting (high in the hot season, from October to May, and null in cold season). This study is the first successful attempt at propagating cuttings from Malagasy forest species. This result is of particular importance to P. africana, threatened by destructive exploitation in Madagascar. It goes a step further in the domestication of this species by demonstrating the ability of cutting from 10 year old ortets collected in natural forest to root as it offers the possibility of a reliable and effective method of reintroduction for the species in overexploited zones.  相似文献   

11.
Softwood shoots were produced from 40 cm long stem segments placed horizontally in flat trays containing sterilized sand under natural light or shade conditions for subsequent rooting and micropropagation studies in teak (Tectona grandis L.). Higher number of shoots (6.17) per log was produced under natural light as compared to shade conditions. Forcing was also better in natural light as compared to shade in terms of shoot length, number of nodes or leaves. For rooting, 2–4 cm long softwood shoots were excised and treated with either indole-3-butyric acid (IBA) or α-naphthyl acetic acid (NAA) at 0, 1000, 2000 or 3000 μmol·L–1 each or with combinations (1000 + 1000, 2000 + 2000 or 3000 + 3000 μmol·L–1) and then placed in flat trays containing autoclaved sand at 25 ± 2ºC in 16 h photoperiod at 35 µmol·m–2·s–1. After 28 days, softwood cuttings treated with IBA + NAA (3000 + 3000 μmol·L–1) had highest rooting percentage (89.3%) with 5.5 mean roots. Shoot apex and nodal explants of softwood cuttings were pretreated with 0.1% (w/v) ascorbic acid, boric acid, activated charcoal, citric acid, glutamine or polyvinylpolypyrollidone (PVP) for 24 h to remove phenolic compounds before surface disinfestation. Glutamine (Gl) and PVP were equally effective resulting in 60% establishment of shoot apices on MS medium supplemented with 10 μmol·L–1 6-benzylaminopurine (BAP) + 5 μmol·L–1 NAA. Using shoot apices, highest (42.80) number of multiple shoots with 54.33 mm shoot length were obtained on MS + BAP (8.8 μmol·L–1) + IBA (2 μmol·L–1) after 45 days. Shoots were successfully rooted and acclimatized to greenhouse  相似文献   

12.
A high-performance liquid chromatography (HPLC) method was developed to determine the contents of miroestrol and deoxymiroestrol in the tubers of Pueraria candollei var. mirifica and P. candollei var. candollei. The linear detection ranges were 0.78-25.00 μg/mL for miroestrol and 1.56-25.00 μg/mL for deoxymiroestrol. The limit of detection (LOD) and limit of quantification (LOQ) were 0.2 and 0.78 μg/mL, respectively, for miroestrol and 0.78 and 1.56 μg/mL, respectively, for deoxymiroestrol. Our results suggest that both varieties of P. candollei can produce miroestrol and deoxymiroestrol and that the developed HPLC method can be applied for quality control of plants and their products.  相似文献   

13.
The insecticidal activity of crude essential oil extracted from Cymbopogon schoenanthus and of its main constituent, piperitone, was assessed on different developmental stages of Callosobruchus maculatus. Piperitone was more toxic to adults with a LC(50) value of 1.6 microl/l vs. 2.7 microl/l obtained with the crude extract. Piperitone inhibited the development of newly laid eggs and of neonate larvae, but was less toxic than the crude extract to individuals developing inside the seeds.  相似文献   

14.
Some conservation based agroforestry systems (AFS) were developed for possible adoption in place of high risk rainfed farming on land capability classes Ito IV of a typical topo-sequence of foothill north India. The agri-silvi-horticulture system integrating leucaena, lemon, papaya and turmeric on class I irrigated land provided sustainable mean net returns of Rs. 17066 against Rs. 7852 ha.–1 yr.–1 from double cropped agricultural system. The intercropping of cluster beans with leucaena gave the highest net returns of Rs. 3540 ha.–1 yr.–1 in the agri-silvicultural system adopted on class II land. Eucalyptus terettcornis (Smith) in top and Bhabbar grass (Eulaliopsis binata Retz) in the understorey on a sandy loam class III land gave four years (1985–1988) mean air dry grass yield of 4.2 (used for paper pulp) from October and 1.19 t. ha–1 yr.–1 (used for fodder) from June cut. The net returns from grass alone were Rs. 4672 against Rs. 1679 ha.–1 yr.–1 from rainfed field crops raised on an adjoining plot. The returns from trees would be additional. Bhabbar grass raised under Acacia species on a 25 to 30% sloping gravelly class IV land provided yield varying from 2.18 to 4.31 from October cut and 0.50 to 1.1 t. ha.–1 yr.–1 from June cut with 6 years mean of 3.9 t. ha.–1 yr.–1 which at 1988 prices provided net returns of Rs. 2402 ha–1. These AFS proved superior to traditional farming on each land capability class.  相似文献   

15.
Variation of traits that include height, diameter at breast height (DBH), stem volume, crown width, straightness, wood basic density, tracheid length and width of open-pollinated progenies from clonal seed orchard of Pinus massoniana was analyzed. Differences in traits such as growth, tree form and wood quality among families was significant, which indicated that the improvement potential was notable. Heritability of height and wood basic density reached 0.691 and 0.640, respectively. According to a correlation analysis between traits, stem straightness could be improved indirectly when growth traits are improved; growth traits were significantly correlated with wood basic density; and wood basic density was not significantly correlated with length and width of the tracheid. Under the selection ratio of 10%, genetic gains were 19.74% and 19.32% respectively, and selected families from the progeny test stands at the age of five years and eight years were the same. Genetic correlation of height, DBH and stem volume was also significant at the level of 0.01. These show that selection of the short rotation of P. massoniana for pulp and paper use would be efficient for five-year-old trees. According to the comparison of the heritability of all the traits and taking into account the result of canonical correlation analysis, height could be considered as the most important index for selection. Given wood quality of all the families, and flowering and fruit settings of the clones in a seed orchard, twelve fine families were selected at 10% selection ratio of height growth and stem volume. Translated from Scientia Silvae Sinicae, 2005, 41(6): 43–49 [译自: 林业科学]  相似文献   

16.
In forest and conservation nurseries in the Pacific Northwest USA, seedling production can be limited by root diseases caused by fungi in the genera Fusarium Link:Fr., Cylindrocarpon Wollenw., Phytophthora de Barry, and Pythium Pringsh. Fusarium, Cylindrocarpon, and Pythium are the most ubiquitous, whereas incidence of Phytophthora is mostly associated with coastal bareroot nurseries. All of these root pathogens are encouraged by water saturated soils or media. Seedlings infected with Fusarium, Phytophthora, or Pythium often appear chlorotic or necrotic with extensive root decay. Cylindrocarpon often causes serious root decay without shoot symptoms. The best approach to mitigate losses from these diseases is to use a holistic integrated pest management program. This program should combine chemical controls with cultural practices, particularly those that increase soil permeability and drainage and reduce potential sources of inoculum, especially by disinfesting seeds and containers reused for crops. In general, we found that seedlings meeting nursery specifications for outplanting on forest soil (proper height, root collar diameter, healthy shoot color, lack of disease symptoms) but having these disease organisms on their root systems perform as well as non-infected seedlings.  相似文献   

17.
The ethanol extract and fractions from Coccoloba acrostichoides aerial parts were assayed for in vitro antimicrobial activity. The extract was active against the assayed bacteria while most of the fractions also inhibited fungal growth, especially the n-hexane and EtOAc fractions. The isolated beta-sitosterol and betulin were tested, being the last one active against Fusarium oxysporum.  相似文献   

18.
Amarowicz R  Dykes GA  Pegg RB 《Fitoterapia》2008,79(3):217-219
Tannins were fractionated from acetonic extract preparations of phenolic compounds from Phaseolus vulgaris, Fagoypyrum esculentum, Corylus avellana and Juglans nigra. Wide variations in antibacterial activities ranging from MICs of 62.5 to 500 microg/ml were apparent. Of particular note was a relatively high level of activity (62.5 to 125 microg/ml) for all extracts against Listeria monocytogenes.  相似文献   

19.
Alkaloids comprise one of the largest groups of plant secondary metabolites including vinca alkaloids. The ability of six alkaloids from Veratrum lobelianum, one from Veratrum nigrum and three from Peganum nigellastrum to modify transport activity of MDR1 was studied. Flow-cytometry in a multidrug-resistant human MDR1-gene-transfected mouse lymphoma cells (L5178Y) was applied. The inhibition of multidrug resistance was investigated by measuring the accumulation of rhodamine-123 in cancer cells.Veralosinine and veranigrine were the most effective resistance modifiers. In a checkerboard method veralosinine and veranigrine enhanced the antiproliferative effects of doxorubicin on MDR cells in combination. The structure-activity relationships were discussed.  相似文献   

20.
Ethyl acetate and chloroform extracts from aerial parts of Portulaca werdermannii and P. hirsutissima were tested in lymphoproliferation assays and axenic cultures of Leishmania amazonensis and Trypanosoma cruzi. Both extracts of P. werdermannii and P. hirsutissima had a potent inhibitory activity on lymphocyte proliferation. On the contrary, only the chloroformic extract of both plants inhibited L. amazonensis growth, without effect on T. cruzi cultures. These results indicate these Portulaca species as potential sources of new active molecules for the treatment of leishmaniasis and immune-mediated pathologies.  相似文献   

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