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1.
Nabin C. Barua Ram P. Sharma K.P. Madhusudanan Gopalakrishna Thyagarajan Werner Herzt 《Phytochemistry》1980,19(10):2217-2218
Isolation of daphnethin 7-methyl ether, daphnetin dimethyl ether, daphnetin methylene ether, daphnetin 7-methyl-8(3,3-dimethylallyl) ether and 3,4-dimethoxy-2-hydroxycinnamic acid from Artemisia caruifolia is reported. 相似文献
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Madhusudanan KP Chattopadhyay SK Tripathi V Sashidhara KV Kumar S 《Phytochemical analysis : PCA》2002,13(1):18-30
Ammonium cationisation has been used for taxoid profiling of partially purified methanolic extracts of needles of Taxus wallichiana growing in different regions of the Himalayas (Kashmir, Himachal Pradesh, UP Hills, Darjeeling, Sikkim and Arunachal Pradesh) by electrospray ionisation tandem mass spectrometry (MS/MS). The MS/MS spectra of the [M + NH4]+ or [M + H]+ ions gave structurally diagnostic fragment ions which revealed information about the taxane skeleton as well as the number and nature of the substituents. The rearranged 11(15-->1)-abeo-taxanes showed a characteristic elimination of the hydroxyisopropyl group with an acetoxy/benzoyloxy group from C-9. The identification of the taxoids was achieved by comparison of the MS/MS spectra with those of authentic taxoids or was based on biogenetic grounds. The results were corroborated by liquid chromatography-MS analysis. Out of the 50 taxoids identified, 21 belonged to the rearranged class. The presence of paclitaxel in the samples from four regions was confirmed: the study also revealed the occurrence of several basic taxoids in these samples. MS/MS profiling by electrospray ionisation was shown to be a fast and reliable technique for the analysis of taxoid samples. 相似文献
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R.N. Baruah R.P. Sharma K.P. Madhusudanan G. Thyagarajan Werner Herz Ramaswamy Murari 《Phytochemistry》1979,18(6):991-994
Isolation and structure determination of orientalide, a new melampolide closely related to the acanthospermals, from Sigesbeckia orientalis is reported. 相似文献
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Mallikarjun S Beelagi SR Santosh Kumar Uma Bharathi Indrabalan Sharanagouda S Patil Ashwini Prasad KP Suresh Shiva Prasad Kollur Veeresh Santhebennur Jayappa Siddappa B Kakkalameli Chandrashekar Srinivasa Prabhakarareddy Anapalli Venkataravana Chandan Shivamallu 《Bioinformation》2021,17(4):479
Crimean-Congo hemorrhagic fever (CCHF) virus is one among the major zoonosis viral diseases that use the Hyalomma ticks as their transmission vector to cause viral infection to the human and mammalian community. The fatality of infectious is high across the world especially in Africa, Asia, Middle East, and Europe. This study regarding codon usage bias of S, M, and L segments of the CCHF virus pertaining to the host Homo sapiens, reveals in-depth information about the evolutionary characteristics of CCHFV. Relative Synonymous Codon Usage (RSCU), Effective number of codons (ENC) were calculated, to determine the codon usage pattern in each segment. Correlation analysis between Codon adaptation index (CAI), GRAVY (Hydrophobicity), AROMO (Aromaticity), and nucleotide composition revealed bias in the codon usage pattern. There was no strong codon bias found among any segments of the CCHF virus, indicating both the factors i.e., natural selection and mutational pressure shapes the codon usage bias. 相似文献
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Paulo HG Mansur Lacordaire KP Cury José OB Leite Adriano A Pereira Nilson Penha-Silva Adriano O Andrade 《Biomedical engineering online》2010,9(1):29
Background
The main problem of tremor is the damage caused to the quality of the life of patients, especially those at more advanced ages. There is not a consensus yet about the origins of this disorder, but it can be examined in the correlations between the biological signs of aging and the tremor characteristics. 相似文献7.
A systematic investigation of trichloroacetic acid (TCA) and trifluoroacetic acid (TFA)-induced equilibrium unfolding of native horse cytochrome c has been carried out using a combination of optical spectroscopy and electrospray ionization mass spectroscopy (ESI MS). In the presence of an increasing concentration of TCA the native cytochrome c does not undergo significant unfolding but stabilization of a partially folded intermediate is observed. This TCA-induced partially folding intermediate of cytochrome c had an enhanced secondary structure and slightly disrupted tertiary structure compared to native protein and undergoes extensive unfolding in the presence of TFA. However, in the presence of an increasing concentration of TFA, cytochrome c was found to undergo extensive unfolding characterized by a significant breakdown of the secondary and tertiary structure of protein. The TFA-unfolded cytochrome c was found to undergo folding in the presence of TCA and low guanidine hydrochloride (GdmCl) resulting in the stabilization of the partially folded intermediate. The effectiveness of TCA as compared to TFA in the stabilization of intermediates was further supported by the observation that low concentrations of TCA were found to induce refolding of HCl-denatured cytochrome c whereas, under similar concentrations of acid, no significant effect on the unfolded structure of protein was observed in the presence of TFA. ESI MS studies indicated that the trichloroacetate anion has a greater affinity for cytochrome c compared to trifluoroacetate anion, which might be the reason for the stabilization of the native-like folded intermediate during TCA-induced denaturation of cytochrome c as compared to extensive unfolding observed in the presence of TFA. 相似文献
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On gamma irradiation of potato tubers at sprout-inhibiting dose (10 krad) the cresolase activity showed a 45% increase while catecholase was reduced by 25%. This reduced the ratio of catecholase to cresolase from 11–12 in unirradiated to 5–6 in irradiated potatoes. Chlorogenic acid oxidation was enhanced by about 25% on irradiation. The increase in the oxidation of p-cresol corresponded with the production of diphenolic compounds. The process of activation of cresolase was slow, reversible and oxygen dependent. A comparative study of the isoenzyme pattern suggested that this activation was due to conformational change, rather than synthesis of new protein. 相似文献
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γ-Irradiation of preclimacteric banana resulted in a gradual increase in fructose content, which reached a maximum in 6 days. Although the catabolism of glucose-U-14C was less in irradiated banana, incorporation of label into fructose was high. Initial fructose accumulation in irradiated banana may be due to a shift in glucose utilization from the glycolytic to the pentose phosphate pathway. The ratio of resporatory CO2 from glucose-6-14C and glucose-1-14C was halved in irradiated bananas indicating predominance of the pentose phosphate pathway. The radioactivity of fructose derived from glucose-6-14C was almost twice that from glucose-1-14C in irradiated bananas, whilst in control both fruit the labelled precursors yielded equal amounts. Studies on individual enzymes in these two pathways showed an increase in phosphorylase, phosphoglucomutase, glucose-6-phosphate dehydrogenase and fructose-6-phosphatase and a decrease in hexokinase in irradiated banana. 相似文献