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91.
Nisar M Kaleem WA Khan I Adhikari A Khan N Shah MR Khan IA Qayum M Samiullah Ismail M Aman A 《Fitoterapia》2011,82(7):1008-1011
Zizyphus oxyphylla Edgew is used in Pakistan as a folk medicinal remedy for inflammatory conditions, pains especially rheumatic pain, fevers, allergy and diabetes. The aim of the current study was to scientifically validate the folk use of Z. oxyphylla Edgew by using the isolated compound in vitro and in vivo levels. Kushecarpin A was isolated from ethyl acetate fraction of the plant crude extract. Molecular docking simulations predicted Kushecarpin A as a potential new lipoxygenase (LOX) inhibitor. Kushecarpin A showed significant lipoxygenase inhibition (IC50: 7.2 ± 0.02 μM) thus validated computational prediction. It also exhibited significant and highly significant inhibition (p < 0.05 and p < 0.01) of carrageenan-induced hind paw oedema at the doses of 5, 10 and 20 mg/kg. Kushecarpin A seems to be a potentially new anti-inflammatory compound responsible for anti-inflammatory activities of Z. oxyphylla Edgew. In vitro and in vivo anti-inflammatory inflammatory activities were found in good agreement with the folk medicinal use of Z. oxyphylla Edgew in inflammatory disorders. 相似文献
92.
Khan I Nisar M Ahmad M Shah H Iqbal Z Saeed M Halimi SM Kaleem WA Qayum M Aman A Abdullah SM 《Fitoterapia》2011,82(2):276-281
A new taxoid Taxawallin I (1) along with two known taxoids (2-3) were isolated from methanolic bark extract of Taxus wallichiana Zucc. Structural characterization was confirmed by mass and NMR spectral techniques. Taxawallin I exhibited significant in-vitro anticancer activity against HepG2, A498, NCI-H226 and MDR 2780AD cancer lines. Tubulin binding assay was performed to assess its tubulin binding activity. Molecular docking analysis was performed to study the potential binding mode inside the taxol binding site of β-tubulin. 相似文献
93.
The methanol extract of the Careya arborea Roxb. bark significantly reduced castor oil-induced diarrhoea in mice. This effect supports the local traditional use of the plant against diarrhoea. 相似文献
94.
Summary Four species of fast growing annual plant viz.Hibiscus sabdariffa, Crotalaria juncea, Tephrosia candida andHibiscus cannabinus and a variety of reed, Neyraudia reynaudiana were evaluated in the laboratory for their pulp and paper making properties. Data on proximate chemical analysis of raw materials, unbleached and bleached pulp properties, morphological properties of fibres and physical strength properties of paper sheets were evaluated. The unbleached pulp yields were 44.90–53.20% with all the five plant materials, while bleached pulp yields varied from 39.80–50.60%. The average fibre lengths and diameters of the unbleached pulp obtained from the five plant species were within the range of 0.75 mm–2.15 mm and 20–22 pun respectively. Paper hand sheets, made with bleached pulps (45° SR) obtained from the five plant species, gave burst indices 2.75–3.92 kPa m2/g, tear indices 3.73–9.61 m N m2/g and tensile indices 37.27–47.81 N mg–1, indicating adequate strength properties for writing and printing type of paper.The authors thank Director, Regional Research Laboratory (CSIR), Jorhat, India, for his kind permission to publish this paper. The authors also wish to thank B. N. Tosh, JPF for his assistance. 相似文献
95.
Green stem cuttings, obtained from 2-year old managed stockplants, with 30, 50 or 100% leaf area were rooted in a non-mist propagator following treatment with 0, 0.2, 0.4 or 0.8% IBA solution. The rooted cuttings were transferred to polythene pots and grown in a nursery for 12 weeks. Rooting percentages of IBA treated cuttings did not significantly differ from those of control cuttings. Likewise leaf area did not significantly influence the percentage of cuttings that rooted. The effects of leaf area and/or IBA treatment in the propagation unit were manifested on the growth of rooted cuttings in polythene pots. Number of roots increased with the increase in IBA concentration and this response was enhanced by increasing leaf area. Root biomass increased with the increase in leaf area even in the control cuttings. Root development was highly influenced by the leaf area and IBA, and hence the growth of rooted cuttings. Cuttings treated with 0.2 or 0.4% IBA at 100% leaf area yielded the best performing rooted cuttings. 相似文献
96.
Development of leaf rust (Melampsora ciliata) in different species, hybrids and cultivars of poplar (Populus spp.) was studied in nursery‐grown plants. Five different criteria were used to assess the disease development. The mean disease index on 10 August was 9.4% which increased to 70.0% on 10 October. The lowest disease index (5.5%) was recorded in P. yunnanensis whereas the maximum was recorded in P. × euramericana‘Rubra‐Poiret’ (59.5%). The apparent infection rate per unit per day was highest in P. nigra × P. trichocarpa (9.7 × 10–2) whereas the minimum occurred in P. maximowiczii × P. berolinensis‘Oxford’ (3.3 × 10–2). The area under the disease progress curve was a maximum in P. × euramericana‘Rubra‐Poiret’ (26.7) and a minimum in P. yunnanensis (1.6). Complete defoliation by the first half of October occurred in P. nigra × P. trichocarpa, which also had the maximum apparent infection rate and area under the disease progress curve. Inoculum production was highest in P. nigra × P. trichocarpa and lowest in P. maximowiczii × P. berolinensis‘Oxford’. 相似文献
97.
We studied the effects of hyperhydricity on subcellular ultrastructure and physiology of leaves during in vitro regeneration of apple plants. Morphological, anatomical and ultrastructural differences between healthy leaf tissues obtained from greenhouse-grown plants and healthy and hyperhydric leaves obtained from shoots raised from nodal shoot explants in a bioreactor were investigated by electron microscopy and confocal laser scanning microscopy. Compared with healthy leaves, hyperhydric leaves showed abnormal, often discontinuous development of the epidermis and cuticle. Stomata were malformed. The leaf lamina appeared thickened and was characterized by poor differentiation between the palisade and spongy mesophyll tissue. Hyperhydric leaves had a significantly lower chloroplast number per cell and chloroplasts showed reduced thylakoid stacking compared with healthy leaves. Hyperhydricity resulted in a general decrease in concentrations of reduced and oxidized pyridine nucleotides, reflecting a reduction in metabolic activity. The activities of antioxidant enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were higher in hyperhydric leaves than in healthy leaves, indicating that hyperhydricity was associated with oxidative stress. Chlorophyll fluorescence measurements provided evidence of oxidative damage to the photosynthetic machinery in hyperhydric leaves: photochemical efficiency of photosystem II, effective quantum efficiency and photochemical quenching were all lower in hyperhydric leaves compared with healthy leaves. 相似文献
98.
Wafo P Kamdem RS Ali Z Anjum S Begum A Oluyemisi OO Khan SN Ngadjui BT Etoa XF Choudhary MI 《Fitoterapia》2011,82(4):642-646
A new diterpenoid, 15-angeloyloxy-16,17-epoxy-19-kauronic acid (1), along with five known metabolites, 16-kauren-19-oic acid (2), 6′-hydroxy-2′,3′,4,4′-tetramethoxychalcone (3), isosakuranetin (4), acacetin (5), and kaempferide (6) was isolated from the organic extracts of the roots of Chromoleana odorata. Their structures were determined by spectroscopic evidences. The structures of 1 and 2 were further confirmed by single-crystal X-ray diffraction studies. Compound 2 exhibited significant α-glucosidase inhibitory and antibacterial activities against Escherichia coli and Bacillus subtilis. 相似文献
99.
Fluconazole resistance is becoming an important clinical concern. We studied the in vitro effects of cinnamaldehyde against 18 fluconazole-resistant Candida isolates. MIC90 of cinnamaldehyde against different Candida isolates ranged 100–500 μg/ml. Growth and sensitivity of the organisms were significantly affected by cinnamaldehyde at different concentrations. The rapid irreversible action of this compound on fungal cells suggested membrane-located targets for its action. Insight studies to mechanism suggested that cinnamaldehyde exerts its antifungal activity by targeting sterol biosynthesis and plasma membrane ATPase activity. Inhibition of H+-ATPase leads to intracellular acidification and cell death. Toxicity against H9c2 rat cardiac myoblasts was studied to exclude the possibility of further associated cytotoxicity. The observed selectively fungicidal characteristics against fluconazole-resistant Candida isolates signify a promising candidature of this essential oil as an antifungal agent in treatments for candidosis. 相似文献
100.
This paper explores the influence over time of past policies on people’s attitudes towards the use of forestland in Bangladesh.
The discourses of the attitudes of people were captured from the observed social tradition towards forest resources. Forests
were reserved systematically and solely through the Forest Department. The conservation processes were not participatory,
and rights and tenure were strictly controlled. People were socially excluded and alienated from the forest, and the socio-political
factors stimulated negative attitudes among people. Forests were considered to be government property, and therefore managing
forests was the responsibility of the government. People only used forest resources to meet their own requirements, either
with formal permission or illegally. This situation continued even after the independence of Bangladesh in 1971. As a result,
the forests of Bangladesh have been degraded heavily in recent decades. 相似文献