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Withania somnifera is one of the most important medicinal plants of Ayurveda and finds extensive uses in Indian traditional herbal preparations. In this investigation, selected accessions of the plant were examined for diversity through RAPDs, isoenzymes, polypeptide polymorphism and withanolide profiles. The accessions clustered together with respect to their characteristic profile of major withanolides and represented withaferin A, withanone, withanolide D or withanolide A rich groups. This level of phytochemical diversity as discrete chemotypes is widest and is being first ever documented to occur in Indian population of the plant.  相似文献   
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A 60 days study was conducted to evaluate the efficacy of water extract of Ocimum sanctum Linn. leaf on the immune response and disease resistance of Labeo rohita fingerlings against the Aeromonas hydrophila infection. Ocimum sanctum extract was incorporated in the diets (at 0.0%, 0.05%, 0.1%, 0.2%, 0.5% and 1%) of Labeo rohita, rohu fingerlings (6.6 ± 0.013 g). After 42 days blood, plasma and serum were sampled to determine super oxide anion production, lysozyme activity, total immunoglobulin in plasma, blood glucose, serum total protein, albumin, globulin, albumin:globulin ratio, WBC, RBC, haemoglobin content. Fish were challenged with A. hydrophila after 42 days and mortalities were recorded over 18 days post infection. The results demonstrate enhanced super oxide anion production, lysozyme activity, total immunoglobulin in plasma, serum total protein, globulin, total RBC counts, total WBC counts and haemoglobin content (P < 0.05) in treatments group compared with control group. Dietary O. sanctum extracts of 0.2% showed significantly (P < 0.05) higher protection relative percentage survival (RPS 40.00 ± 5.773%) against A. hydrophila infection than control. These results indicate that O. sanctum leaf extract stimulates the immunity and makes L. rohita more resistant to bacterial infection (A. hydrophila).  相似文献   
14.
Phytochemical investigation of Dodecadenia grandiflora leaves led to the isolation and identification of three phenolic glycosides, designated 1-[(4′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (1), 1-[(6′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (2) and 1-[O-β-d-glucopyranosyl(1→2)-β-d-glucopyranosyl]-oxy-2-phenol (3), along with nine known compounds. Compounds 1, 2, 5 and 9 exhibited significant glucose-6-phosphatase inhibitory activity (63.7, 66.9, 82.9 and 85.4%) with IC50 values of 88.5, 81.0, 51 and 50 μM respectively. On the basis of biological results, a structure–activity relationship has been discussed.  相似文献   
15.
Evidences have suggested that Tectona grandis (TG) attenuates gastric mucosal injury; however its mechanism has not yet been established. The aim of present study was to evaluate the gastroprotective mechanism of ethanolic extract of TG (E-EtOH), butanolic fraction (Fr-Bu) and to identify its active constituents. Anti-ulcer activities were evaluated against cold restraint (CRU) and pyloric ligation (PL) induced gastric ulcer models and further confirmed through H+ K+-ATPase inhibitory activity. Cytoprotective activity was evaluated in alcohol (AL) induced gastric ulcer model and further through PGE2 level. E-EtOH and Fr-Bu attenuated ulcer formation in CRU. Moreover E-EtOH and Fr-Bu displayed potent anti-secretory activity as evident through reduced free acidity and pepsin activity in PL, confirmed further by in vitro inhibition of H+ K+-ATPase activity. In addition cytoprotective potential of E-EtOH and Fr-Bu were apparent with protection in AL model, increased PGE2 content and enhanced mucin level in PL. Phytochemical investigations of Fr-Bu yielded terpenoides and a phenolic glycoside, verbascoside. The anti-secretory mechanism of verbascoside mediated apparently through inhibition of H+ K+-ATPase with corresponding decrease in plasma gastrin level, is novel to our finding. Gastroprotection elicited by TG might be through proton pump inhibition and consequent augmentation of the defensive mechanism.  相似文献   
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ABSTRACT

The interactions between salinity and different nitrogen (N) sources nitrate (NO3 ?), ammonium (NH4 +), and NO3 ? + NH4 + were investigated on Indian mustard (Brassica juncea cv. RH30). Treatments were added to observe the combined effect of two salinity levels (8 and 12 ds m? 1) and three nitrogen sources (NO3 ?, NH4 +, and NO3 ? + NH4 +) on different growth parameters and mineral composition in different plant parts, i.e., leaves, stem, and root. Salinity has been known to affect the uptake and assimilation of various essential nutrients required for normal growth and development. Different growth parameters, i.e., leaf area, dry weight of different plant parts, absolute growth rate (AGR), relative growth rate (RGR), and net assimilation rate (NAR) declined markedly by salinity at pre-flowering and flowering stages. All growth indices were less sensitive to salinity (12 d s m? 1) with the nitrate form of nitrogen. It is pertinent mention that a high dose (120 kg ha? 1) of nitrogen in ammonium form NH4 +, acted synergistically with salinity in inhibiting growth. Plants fed with combined nitrogen (NO3 ? + NH4 +) had an edge over individual forms in ameliorating the adverse effects of salinity on growth and yield. Under salt stress, different nutrient elements such as N, phosphorus (P), potassium (K+), and magnesium (Mg2 +) were decreased in different plant parts (leaves, stem, and root). The maximum and minimum reduction was observed with ammoniacal and combined form of nitrogen, respectively, while the reverse was true of calcium (Ca2 +), sodium (Na+), chloride (Cl?), and sulfate (SO4 2?) at harvest. Nitrogen application (120 Kg ha? 1) in combined form had been found to maintain highest concentrations of N, P, Mg2 +, and Ca2 + along with reduced concentrations of Na+, Cl?, and SO4 2 ?. However, reverse was true with ammoniacal form of nitrogen.  相似文献   
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Accurate early antemortem diagnosis of tuberculosis in dromedary camels is difficult due to the lack of reliable diagnostic test. The present study aimed to evaluate a lateral flow assay-based kit (rapid assay kit) in tuberculosis diagnosis that employs immuno-chromatographic detection of antibodies in serum, plasma, or whole blood. In a dromedary camel herd comprising 337 animals located at Bikaner, Rajasthan, India, 50 adult weak camels (11 males and 39 females) were tested by applying a single intradermal tuberculin test (SIDT) and rapid assay kit. A total of 14 animals (2 males, 12 females) were found positive in rapid assay. In SIDT, four animals revealed a positive reaction in the neck region and seven animals in the tail base. Another male animal was found SIDT positive but negative in rapid assay; it died after 12 months. Nine rapid assay positive animals died asymptomatically in 1- to 11-month period revealing postmortem tuberculosis lesions that were confirmed by Ziehl-Neelsen staining and histopathology. No tuberculous lesion was evident in the animal found positive in SIDT alone. Results of the present study indicated that serological tests like rapid assay kit can serve as a reliable test for antemortem diagnosis of tuberculosis in dromedary camel.

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20.
Limonoid glucosides (primarily limonin 17-beta-D-glucopyranoside, LG) were extracted from grapefruit molasses by supercritical fluid extraction using a supercritical carbon dioxide-ethanol (SC CO(2)-ethanol) system. Extraction conditions to maximize the yield of LG were determined by varying pressure, temperature, ethanol concentration, and extraction time. The highest yield of LG at 0.61 mg/g molasses was obtained at a pressure 48.3 MPa, a temperature of 50 degrees C, 10% ethanol (X(Eth) = 0.1), and 40 min of extraction time at a flow rate of 5.0 L/min. The results demonstrated that SC CO(2) extraction of limonoid glucosides from grapefruit molasses has practical significance for commercial production.  相似文献   
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