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51.
52.
New withanolides from Mandragora officinarum: First report of withanolides from the Genus Mandragora
Two new withanolides named mandragorolide A (1) and mandragorolide B (2) were isolated from the MeOH extract of the whole plant of Mandragora officinarum of Jordanian origin, along with five known withanolides namely larnaxolide A (3), withanolide B (4), datura lactone 2 (5), withanicandrin (6) and salpichrolide C (7). Compound 3 has been reported only once before, from the leaves of Larnax glabra. This is the first report of withanolides of different biogenetic types from the genus Mandragora. Isolation of known fatty compounds, coumarins, sterols and tropane alkaloids was also achieved in this study. 相似文献
53.
The rural folk of North Andaman, India use the traditional medicine for their primary health care. Folklore medicinal uses of 72 interesting medicinal plant species along with botanical name, local name, family, habit, part used, disease for which the drug is administrated, mode of administration are presented. These 72 plant species which provide the crude drugs pertain to 67 genera and 43 families of Magnoliophyta from tropical rainforests. These plants used to cure 40 ailments. Most remedies were taken orally, accounting for 76% of medicinal use. Most of the remedies were reported to have been from trees (55.6%) and herb (22.2%) species. The most widely sought after plant parts in the preparation of remedies in the areas are the stem bark (33.8%) and root (23.9%). 相似文献
54.
Summary The dynamics of five inoculated strains of heterocystous blue-green algae (BGA) and indigenous algae were studied for 1 month in 1-m2 microplots of five soils previously air-dried or oven-dried. The same soils were then dried and resubmerged for another 2 months to study the effect of controlling algal grazers with neem (Azardirachta indica) seeds on the revival and dynamics of indigenous and inoculated algae. During the month following inoculation, inoculated BGA multiplied to some extend in all soils but never dominated the total algal flora. They rarely dominated the indigeneous heterocystous BGA, and did so only when the growth of N2-fixing BGA was poor or after the decline of blooms of indigenous strains. Once the soils were dried, two of the five inoculated strains did not reappear. During the 1st month following rewetting, the remaining inoculated strains again exhibited poor growth; however, after 2 months of submergence, inoculated Aulosira fertilissima developed an agronomically significant bloom in neem-treated plots of two soils. Correlations between acetylene-reducing activity and heterocystous BGA populations indicated a major contribution by indigenous BGA and a minor contribution by inoculated BGA to the N2-fixing activity of the soils during the first experiment and the 1st month of the second experiment. The establishment of inoculated BGA exhibited clear differences among strains but was less affected by the nature of the soil and heat treatment. Neem application might have had a delayed positive effect on the late establishment of inoculated A. fertilissima and favored BGA growth and N2 fixation by the total algal population.Visiting Scientist at IRRI 相似文献
55.
Activation of the c-myb locus by viral insertional mutagenesis in plasmacytoid lymphosarcomas 总被引:32,自引:0,他引:32
G L Shen-Ong M Potter J F Mushinski S Lavu E P Reddy 《Science (New York, N.Y.)》1984,226(4678):1077-1080
56.
ABSTRACT We evaluated combinations of two strains of plant growth-promoting rhizobacteria (PGPR) formulated with the carrier chitosan for the ability to induce growth promotion of tomato plants and resistance to infection by Cucumber mosaic virus (CMV). Each PGPR combination included GB03 (Bacillus subtilis) and one of the following PGPR strains: SE34 (B. pumilus), IN937a (B. amyloliquefaciens), IN937b (B. subtilis), INR7 (B. pumilus), or T4 (B. pumilus). The PGPR combinations formulated with chitosan are referred to as biopreparations. Tomato plants treated with each of the biopreparations appeared phenotypically and developmentally similar to nonbacterized control plants that were 10 days older (referred to as the older control). When plants were challenged with CMV, all plants in the biopreparation treatments and the older control treatment had significantly greater height, fresh weight, and flower and fruit numbers than that of plants in the CMV-inoculated same age control treatment. CMV disease severity ratings were significantly lower for biopreparation-treated and older control tomato plants than for that of same age control plants at 14 and 28 days postinoculation (dpi). CMV accumulation in young noninoculated leaves was significantly less for all biopreparation-treated plants and those in the older control than for the same age control plants at 14 dpi and for four of the five biopreparation treatments at 28 dpi. In those tomato plants shown to be infected, the amount of CMV in noninoculated leaves was significantly lower for three of the biopreparation treatments and the older control treatment at 14 dpi and biopreparation G/INR7 treatment at 28 dpi when compared with the control treatment. These data show that treatment of tomato plants with biopreparations results in significant enhancement of growth and protection against infection by CMV. 相似文献
57.
Evidence for two predominant viral lineages,recombination and subpopulation structure in begomoviruses associated with yellow vein mosaic disease of okra in India 下载免费PDF全文
V. Venkataravanappa H. C. Prasanna C. N. Lakshminarayana Reddy M. Krishna Reddy 《Plant pathology》2015,64(3):508-518
Yellow vein mosaic disease (YVMD) caused by whitefly‐transmitted begomoviruses is an economically significant viral disease of okra. In this study, a survey of begomoviruses associated with YVMD was carried out in eight states and two union territories of India. A total of 92 full‐length DNA‐A components were sequenced and characterized. Sequence comparisons and population structure analysis revealed the existence of four begomovirus species. Two novel species were detected with several recombinationally derived genome fragments that probably originated from begomoviruses known to infect malvaceous and non‐malvaceous hosts. Among the four species, Bhendi yellow vein Maharastra virus (BYVMaV) and Bhendi yellow vein Madurai virus (BYVMV) were found to be predominant in okra, with BYVMV having a pan‐India distribution. There was evidence for a high degree of genetic variability and subpopulation structure within these four species. Neutrality tests suggested the occurrence of purifying selection acting upon these populations. The results of the current study have uncovered the diversity and genetic structure of okra‐infecting begomoviruses in India and generated potentially useful information for developing management strategies for YVMD. 相似文献
58.
59.
Reddy IJ David CG Selvaraju S Mondal S Ravi Kiran G 《Tropical animal health and production》2012,44(6):1311-1317
The objective of this was to establish the effects of red spectrum of light (650 nm, treated n = 12) and normal spectrum of light (450 nm control = 12) on GnRH-I mRNA expression, amplitude and frequency of luteinizing hormone (LH), and egg production from 72-82 weeks of age in white leghorn hens. Birds exposed to red spectrum of wavelength significantly improved (P < 0.01) steroid hormone, and egg production improved over old laying 72 to 82 weeks. Weekly interval profiles followed the same pattern. At 77th weeks of age blood, samples from both the groups were collected at every 3 h for 36 h to study the pulsatile secretion of LH surges. Plasma LH concentration was higher (P < 0.01) in treated birds with more number of frequencies and amplitude LH surges in plasma of treated birds. LH frequencies were more pronounced and advanced during 36 h of sampling at 3 h interval in treated birds. Weekly interval of plasma LH, E2β, and P(4) concentrations increased (P < 0.01) in treated birds from 72 to 82 weeks of age. GnRH-I mRNA concentration was significantly (P < 0.01) higher in birds exposed to red spectrum of light compared to controls. It is hypothesized that exposure of birds to red spectrum of light-enhanced (P < 0.01) GnRH-I mRNA with more number of yellow yolky follicles was found in birds exposed to red spectrum of light during 77 days (72-82 weeks of age) of experimental period. It is concluded that higher levels of GnRH-I mRNA, LH, E2β, and P(4) concentration with lower incidence of pause days enabled the birds to lay more eggs even later in the productive period by modulating the wavelengths of light under normal husbandry conditions. 相似文献
60.
Reddy KK Ravinder T Prasad RB Kanjilal S 《Journal of agricultural and food chemistry》2011,59(2):564-569
Synthesis of 10 capsiate analogues was conducted by lipase-mediated (Novozyme 435) esterification of vanillyl alcohol with different fatty acids. The antioxidant activity of the synthesized capsiates was evaluated using three in vitro assays: DPPH radical scavenging assay (polar medium), Rancimat assay (nonpolar medium), and autoxidation of linoleic acid (micellar medium). The objective of this study is to find the influence of structural characteristics of the alkyl chain of capsiate analogues on their antioxidant activity. In these assays, BHT and α-tocopherol were used as reference compounds. Both DPPH and Rancimat assays did not show any specific trend of antioxidant activity with the increase in lipophilicity and also with the type of fatty acids grafted to the phenolic moiety. In the Tween 20 micellar system for the inhibition of autoxidation of linoleic acid, vanillyl ester attached to a C18 alkyl chain (vanillyl stearate, oleate, and ricinoleate) exhibited maximum inhibition of autoxidation of linoleic acid. 相似文献