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371.
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Abstract Free living nematode Caenorhabditis elegans was used as a test system for screening anthelmintic phenolics. The most effective concentrations (100, 500 and 1000 μg ml−1) were used against root knot nematode Meloidogyne incognita. Effect of these phenolics was determined on growth and development of host plant Capsicum frutescens cv. California Wonder, Second stage juveniles of M. incognita were hatched from egg masses collected from roots of host plant and subjected to similar phenol concentrations for 48 h. Mortality of M. incognita was recorded on the basis of parameters used for test organism bioassay. Both healthy and inoculated plants of C. frutescens cv. California Wonder were treated withsolutions of salicylic acid (SA) and p-betahydroxy benzoic acid (BA) so that each pot received 100, 500 and 1000 mg phenol. Control plants were supplied with distilled water, Plants were uprooted 21 days after inoculation and roots were gall indexed. Some plants were left in the pots for further growth and development. Surface sterilised seedlings of host plant were raised and inoculated with second stage Juveniles of M. incognita. Thereafter observations were recorded on the vegetative and reproductive parameters of the plants. Drench application of SA and BA were found quite effective with no apparent phytotoxic effect.  相似文献   
373.
Summary Axenic shoot cultures ofCapsicum annuum cv.California Wonder were used as the source for isolation of protoplasts from mesophyll cells. Protoplasts underwent sustained mitotic activity and proliferated to form callus masses on NT or DPD medium enriched with 2,4-D, NAA and BAP each at 1 mg/l level. The callus could be differentiated into whole plants on the differentiation media and plants floweredin vitro under long day conditions.  相似文献   
374.
A new disaccharide, brevobiose (1), has been isolated from the dried twigs of Sarcostemma brevistigma. The structure of 1 has been established as 4-O-(6-deoxy-2-O-methyl-β-d-allopyranosyl)-d-boivinose on the basis of chemical and spectroscopic evidence, and identification of its hydrolysis products.  相似文献   
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Candida infections and related mortality have become a challenge to global health. Nontoxic and natural bioactive compounds from plants are regarded as promising candidates to inhibit these multidrug resistant strains. In the present study, in vitro assays and in silico molecular docking approach was combined to evaluate the inhibitory effect of crude extracts from Allium ampeloprasum and its variety A. porrum on Candida pathogens. Phytochemical screening revealed the presence of phenolic acids and flavonoids in higher quantity. Spectral studies of the extracts support the presence of phenols, flavonoids and organosulfur compounds. Aqueous extract of A. ampeloprasum showed a total antioxidant capacity of 68 ± 1.7 mg AAE/ g and an IC50 value of 0.88 ± 2.1 mg/ml was obtained for DPPH radicals scavenging assay. C. albicans were highly susceptible (19.9 ± 1.1 mm) when treated with aqueous A. ampeloprasum extract. Minimum inhibitory concentrations were within the range of 19–40 μg/ml and the results were significant (p ≤ 0.05). In silico molecular docking studies demonstrated that bioactive phytocompounds of A. ampeloprasum and A. porrum efficiently interacted with the active site of Secreted aspartyl proteinase 2 enzyme that is responsible for the virulence of pathogenic yeasts. Rosmarinic acid and Myricetin exhibited low binding energies and higher number of hydrogen bond interactions with the protein target. Thus the study concludes that A. ampeloprasum and A. porrum that remain as underutilized vegetables in the Allium genus are potential anti-candida agents and their pharmacologically active compounds must be considered as competent candidates for drug discovery.  相似文献   
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Opercular and surfacing activity were observed in the Indian catfish Clarias batrachus and Heteropneustes fossilis. In the series A experiments, the opercular activity was monitored under two experimental conditions, viz., (1) surfacing allowed and (2) surfacing prevented. A statistically significant elevation of the rate of opercular activity was observed when air breathing was prevented in both species. In addition, a significant prevention effect and a time of day dependence of that were noticed in both species. In the series B experiments, temporal patterns of surfacing and air-gulping activities were examined under an artificial LD 12:12 schedule at 2-h intervals over a period of 48 h. The inter air-gulping interval in minutes between two consecutive bouts was also recorded four times each day in both species. A significant 24-h rhythm was found for the rate of surfacing activity and length of the inter air-gulping interval in both species. However, the overall activity appears to be much higher in Heteropneustes fossilis as compared to Clarias batrachus.  相似文献   
380.
A mouse model to estimate the potency of the diphtheria toxoid components in vaccines using Vero cells to detect the neutralizing antibodies in the sera from immunized mice is described. The results obtained with this mouse model correlated significantly with those obtained in the lethal challenge test in guinea-pigs. For this reason it is suggested that the potency test in guinea-pigs be replaced by this mouse model because a considerable reduction in the number of animals used and costs can be achieved by the introduction of this mouse test for the routine control of the potency of the diphtheria component of vaccines.  相似文献   
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