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1.
A circadian feeding rhythm which may be entrained by photoperiod was found in fifth instar caterpillars of the lepidopteran, Achaea janata (L.). Allatectomy reduced the amount of food consumed; this consumption was significantly lower during the fifth instar in both allatectomized and sham-operated insects. An apparent circadian feeding pattern appeared on day 2 in the sham-operated caterpillars. Topical application of the anti-allatin, Precocene-II (50 micrograms/animal) also reduced leaf consumption significantly compared to the respective controls, although these controls maintained the same apparent circadian feeding rhythm on day 2. 相似文献
2.
Two eriophyid mites,Acaphylla theae andCalacarus carinatus, have been known for some time as important pests of tea. In recent years a third eriophyid,Acaphyllisa parindiae, has also become abundant. The vertical distribution of these three species on tea is examined. 相似文献
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The anthocyanins in native Cornus alternifolia, Cornus controversa, Cornus kousa and Cornus florida were quantified by HPLC and characterized by spectroscopic methods. The analyses of C. alternifolia and C. controversa revealed that both contained , and , respectively. Similarly, C. florida and C. kousa showed identical anthocyanin profiles with major anthocyanins as and cyanidin 3-O-glucoside (6), respectively. The amount of anthocyanins , and in C. alternifolia and C. controversa were 8.21, 8.44 and 0.02 mg; and 7.74, 5.92, and 0.02 mg/g of fresh fruits, respectively. The anthocyanins and in C. kousa and C. florida were 0.02 and 0.16 mg; and 0.62 and 0.03 mg/g fresh fruits, respectively. Anthocyanins and were not studied earlier for their inhibition of lipid peroxidation, cyclooxygenase enzymes (COX-1 and COX-2), and tumor cell proliferation. At 50 microg/mL, anthocyanins and inhibited lipid peroxidation by 71% and 68%, respectively. Similarly, they inhibited COX-1 enzymes by 39% and 49% and COX-2 enzyme by 54% and 48%, respectively, at 100 microg/mL. Anthocyanin displayed 50% growth inhibition (IC(50)) at 21, 25, 50, 60, and 75 microg/mL, against HCT-116 (colon), MCF-7 (breast), NCI-H460 (lung), SF-268 (central nervous system CNS), and AGS (stomach) human tumor cell lines, respectively. Similarly, IC(50) values for anthocyanin were 38, 30, 76, 100, and 100 microg/mL against HCT-116, MCF-7, NCI H460, SF-268, and AGS, respectively. This is the first report of the quantification and biological activities of anthocyanins in C. alternifolia, C. kousa and C. florida in addition to the anthocyanins not previously quantified in C. controversa. 相似文献
5.
Biofouling is one of the concerns in the use of titanium for seawater cooled condensers of power plants. Earlier studies have shown that anodized titanium and its alloys with a thin film of anatase (TiO(2)) on its surface can inhibit attachment of Pseudomonas sp. when illuminated with near-UV light (350 - 380 nm). In the present study, a comparison of the photocatalytic inhibition of microbial attachment on titanium surfaces anodized at different voltages was carried out. Thin films of anatase of varying thickness were produced on titanium grade-2 by anodizing in dilute orthophosphoric acid solution at 30 V, 50 V and 100 V. The photocatalytic efficiency of these anodized surfaces was measured by the methylene blue degradation method. The anodised surfaces were exposed to liquid cultures of Gram-negative Pseudomonas sp., Gram-positive Micrococcus sp. and to a mixed algal culture. Photocatalytic inhibition of microbial attachment was maximum on the titanium surface anodized at 30 V, followed by the surface anodized at 50 V and then at 100 V. The photocatalytic inhibition of microbial attachment was also found to be dependent on the cell wall characteristics of the organism. The Gram-negative Pseudomonas sp. with a lipoproteinaceous outer membrane was the most susceptible to the photocatalytic effect, while the Gram-positive Micrococcus sp. with peptidoglycan cell wall showed moderate susceptibility and the algae with siliceous cell wall showed no susceptibility at all. 相似文献
6.
Krishnan LK Varghese N Muraleedharan CV Bhuvaneshwar GS Derangère F Sampeur Y Suryanarayanan R 《Biomolecular engineering》2002,19(2-6):251-253
Measurement of platelet adhesion in vitro is a good indicator of its reactivity to implant devices in vivo. Platelets were labeled with I-125 without affecting its normal morphology and function and the labeled platelets were suspended in platelet poor plasma and exposed to Ti and diamond like carbon-coated (DLC) Ti discs, under dynamic conditions, using a parallel plate flow chamber. The test materials were washed, dried, exposed to a phosphor screen and scanned to get the images. The number of platelets that adhered to Ti was found to be higher than those that adhered to DLC coated Ti sample, irrespective of the shear stress which was varied between 2 and 16 dynes/cm(2). 相似文献
7.
R. K. Sharma M. S. Negi S. Sharma P. Bhardwaj R. Kumar E. Bhattachrya S. B. Tripathi D. Vijayan A. R. Baruah S. C. Das B. Bera R. Rajkumar J. Thomas R. K. Sud N. Muraleedharan M. Hazarika M. Lakshmikumaran S. N. Raina P. S. Ahuja 《Biochemical genetics》2010,48(7-8):549-564
India has a large repository of important tea accessions and, therefore, plays a major role in improving production and quality of tea across the world. Using seven AFLP primer combinations, we analyzed 123 commercially important tea accessions representing major populations in India. The overall genetic similarity recorded was 51%. No significant differences were recorded in average genetic similarity among tea populations cultivated in various geographic regions (northwest 0.60, northeast and south both 0.59). UPGMA cluster analysis grouped the tea accessions according to geographic locations, with a bias toward China or Assam/Cambod types. Cluster analysis results were congruent with principal component analysis. Further, analysis of molecular variance detected a high level of genetic variation (85%) within and limited genetic variation (15%) among the populations, suggesting their origin from a similar genetic pool. 相似文献
8.
R. Kanchana Usha Devi Muraleedharan Seshagiri Raghukumar 《World journal of microbiology & biotechnology》2011,27(9):2125-2131
Two thraustochytrid protists of the genus Thraustochytrium isolated from coastal and mangrove habitats of Goa, India were studied for extracellular alkaline lipase production. Maximum lipase production was supported by a combination of peptone and yeast extract in the growth medium while strong inhibition of enzyme production was observed in presence of glucose. The inducible nature of the enzyme production was evidenced by the requirement of olive oil in the medium. Lipase production was salt-dependent and optimum production required 3.4% (w/v) crude sea salt. Ideal conditions for maximum production of lipases were therefore adopted as incubation at 30 ± 2°C for 168 h at an initial pH of 6.0 in a medium consisting of 0.5% peptone, 0.01% yeast extract, 0.5% olive oil and 3.4% crude salt. Extracellular lipase production by the two thraustochytrid isolates [designated TZ (ATCC #PRA-295) and AH-2 (ATCC #PRA-296)] was increased threefold under these optimized culture conditions. This appears to be the first report on optimization of cultivation conditions for the production of alkaline lipases by thraustochytrids. 相似文献
9.
Daylilies (Hemerocallis) are used medicinally in eastern Asia and extracts of the plant had been shown to inhibit cell proliferation and induce cancer cells to undergo differentiation. In our studies of the constituents of Hemerocallis fulva var. 'Kwanzo' roots, we isolated a series of new [kwanzoquinones A (1), B (2), C (4), D (5), E (6), F (7), G (9)] and known [2-hydroxychrysophanol (3) and rhein (8)] anthraquinones. These compounds were tested in order to determine their potential roles as cancer cell growth inhibitors. Kwanzoquinones A-C and E, kwanzoquinone A and B monoacetates (1a and 2a), 2-hydroxychrysophanol, and rhein inhibited the proliferation of human breast, CNS, colon, and lung cancer cells with GI50 values between 1.8 to 21.1 microg/mL. However, upon exposure of the cancer cells to the GI50 concentrations of the bioactive anthraquinones, most of the cancer cell lines exhibited higher than anticipated levels of cell viability. Co-incubation of the anthraquinones with vitamins C and E increased the viability of breast cancer cells. In contrast, vitamins C and E potentiated the cytotoxic effects of the anthraquinones against the colon cancer cells. None of the anthraquinones inhibited the activity of topoisomerase. 相似文献
10.
Constituents in Easter lily flowers with medicinal activity 总被引:5,自引:0,他引:5
Easter lily (Lilium longiflorum) flowers have been used in traditional medicine for alleviating many ailments. However, the chemical basis of its bioactivity has not been investigated. We have determined bioactive components in Easter lily flowers using lipid peroxidation and cyclooxygenase enzyme inhibitory assays and found to be kaempferol (1), kaempferol glycosides (2, 3, 4, 8, 9 and 10), quercetin glycosides (5, 6 and 7), a regaloside (11), a chalcone (12) and a fatty acid fraction (13). The structures of compounds were determined by NMR, IR, UV/VIS and mass spectroscopic studies. Compound 1 showed the highest COX-1 inhibition (94.1%) followed by 3, 8 and 12 with 38.7, 30.8 and 32.4%, respectively. Only compound 1 inhibited COX-2 enzyme by 36.9% at 80 ppm. In lipid peroxidation inhibitory assay, kaempferol showed 37 and 100 % inhibitions at 1 and 10 ppm, respectively. At 10 ppm, more than 20% inhibition was observed for compounds 4, 7, 10, 11 and 12 and 53% for compound 3. The compounds reported in here are isolated for the first time from Easter lily flowers including novel compounds 10, 11 and 12. Our results suggest that kaempferol and quercetin flavonoids contributed to the anecdotal medicinal properties of Easter lily flowers. 相似文献