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951.
H. Kobayashi N. Morisaki Y. Tago Y. Hashimoto S. Iwasaki E. Kawachi R. Nagata K. Shudo 《Cellular and molecular life sciences : CMLS》1995,51(11):1081-1084
A major cytokinin found in coconut milk was isolted by using the tobacco callus growth-promoting assay as a guide during purification. The structure of the factor was determined to be 14-O-{3-O-[-d-galactopyranosyl-(12)--d--galactopyranosyl-(13)--L-arabinofuranosyl]-4-O-(-L-arabinofuranosyl)--d-galactopyranosyl}-trans-zeatin riboside [G3A2-ZR] by various NMR techniques, including heteronuclear multiple bond connectivity by 2D multiple quantum NMR (HMBC), as well as mass spectroscopy and sugar analysis. The optimum concentration of G3A2-ZR for cytokinin activity in the tobacco callus assay was estimated to be 5×10–6 M, so that G3A2-ZR is one order of magnitude more potent than 1,3-diphenylurea and one order less potent than zeatin riboside. At least 20% of the cytokinin activity of coconut milk could be attributed to G3A2-ZR. 相似文献
952.
Kininase and anti-inflammatory activities of acid carboxypeptidase from Penicillium janthinellum. 总被引:2,自引:0,他引:2
The acid carboxypeptidase from Penicillium janthinellum catalyzed the rapid release of arginine, and the slow release of phenylalanine, proline, serine and glycine from the carboxy-terminal of bradykinin at pH 4.15 to 4.8. Anti-inflammatory activity of the acid carboxypeptidase seems to suggest that the enzyme hydrolyzed bradykinin in vivo. 相似文献
953.
954.
955.
Y. H. Nakanishi M. Kuwabara G. Yoshii Professor T. Nei 《Cellular and molecular life sciences : CMLS》1976,32(1):30-32
Summary The DNP fibres -irradiated under aerobic condition showed a reduction of their diameter, while no remarkable changes were observed in the DNP fibres irradiated under hypoxic condition by scanning electron microscopy. 相似文献
956.
A significant antitumor activity of oridonin (1) and lasiokaurin (2), the kaurene-type diterpenoids of Isodon species, was shown by their i.p. injection to the test mice inoculated by Ehrlich ascites carcinoma. Enmein (8), compounds 9 and 3 were also active under larger dose. Subsequently, the relationship between their chemical structure and antitumor activity was investigated, and the activity of oridonin (1) and lasiokaurin (2) was rationalized in terms of their structural feature. 相似文献
957.
Summary 3-Hydroxy-3-methylglutaric acid (HMG) significantly decreased cholesterol, triglyceride and phospholipid levels in whole serum, serum -lipoproteins and liver of Triton-induced hyperlipidemic rats. Therapeutically 50 mg HMG/kg is equivalent to 200 mg nicotinic acid/kg in lowering all these lipid parameters. HMG may exert its hypolipidemic effect through inhibition of lipoprotein synthesis.Acknowledgments. We are grateful to Dr.M. Saleemuddin for encouragement, Dr.P. E. Schurr, Upjohn Co. USA for generous gift of Triton W. R 1339 and Lady Tata Memorial Trust (India) for financial assistance to one of us (SYKY). 相似文献
958.
Summary In rats 3-hydroxy-3-methylglutaric acid effectively counteracts the lipemic and atherosclerotic response of massive doses of vitamin D2. It regressed the formation of atheromatous arterial lesions. Furthermore the significant decrease in serum -lipoprotein levels on HMG treatment could be due to decrease in VLDL triglyceride and cholesterol levels.Acknowledgments. The authors are indebted to Dr.W. Drell, President, Calbiochem, San Diego, California, USA, for generous gift of HMG and Lady Tata Memorial Trust, India, for providing financial assistance to one of us (S.Y.K.Y.). 相似文献
959.
960.
J. Kobayashi Y. Ohizumi H. Nakamura Y. Hirata K. Wakamatsu T. Miyazawa 《Cellular and molecular life sciences : CMLS》1986,42(9):1064-1065
Summary A novel bromine-containing alkaloid, hymenin, has been isolated from the Okinawan marine spongeHymeniacidon sp. as a potent -adrenoceptor blocking agent and its structure determined to be1 on the basis of the spectral data. 相似文献