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1.
2.
Shiro Tabata Takeshi Ide Yasuyoshi Umemura Kenzo Torri 《Biochimica et Biophysica Acta (BBA)/General Subjects》1984,797(2):231-238
α-Glucosidases or maltases (EC 3.2.1.20) were purified to electrophoretic homogeneity from a respective strain of Sacchromyces cerevisiae which carries a single MAL gene, either MALα, MALβ or MALγ, using gluconate-Sepharose affinity chromography and isoelectrofocusing. Of these maltases, two types of maltase were obtained from the MALγ strain, the pI values of which were 5.6 and 5.9. From the MALα and MALβ strain was obtained only one type of maltase with the pI at 5.6 which was identical to one of the maltases from the MALγ strain. These four maltases possessed the same properties, except for pI. They were monomers with molecular weights of between 66 000 and 67 000. With regard to the substrate specificity, they hydrolyzed maltose and sucrose exclusively but not α-methulglucoside nor maltooligosaccharide. They did not differ in immunological properties. 相似文献
3.
Production of berberine could be induced by adding 6-benzylaminopurine (BAP) to Thalictrum minus cells, cultured in suspension in a medium containing 2,4-dichlorophenoxyacetic acid (2,4-D), early in the growth cycle. In the presence of BAP, the precursor, L-tyrosine, was rapidly converted into berberine which was then released into the medium, whereas substantial amounts of the intermediates, tyramine and dopamine, accumulated in non-berberine-producing cells grown in the same 2,4-D-containing medium without BAP. These results suggest that BAP activated enzymatic reactions subsequent to the formation of the amines in the biosynthesis of berberine.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- BAP
6-benzylaminopurine
- NAA
1-naphthaleneacetic acid
- IAP
6-isopentenylaminopurine
- LS medium
Linsmaier-Skoog medium
- Growth medium
LS medium containing 10-6 M 2,4-D 相似文献
4.
D-manno-3-Heptulose (5) was synthesized by dimethyl sulfoxide-phosphorus pentaoxide oxidation of 1,2:3,4:6,7-tri-O-isopropylidene-D-glycero-D-manno-heptitol (3, prepared from volemitol), followed by hydrolysis. D-ido-3-Heptulose (8) was synthesized similarly by oxidation of 1,2:4,5:6,7-tri-O-isopropylidene-D-glycero-l-galacto-heptitol (7, prepared from D-glycero-l-galacto-heptitol, 6). Another tri-O-isopropylidene derivative (11), having a free primary hydroxyl group, was produced in larger amount than 7, and 11 yielded D-glycero-l-galacto-heptose (14). Compound 8 was also synthesized by way of 1,2:4,5.6,7-tri-O-isopropylidene-D-glycero-l-gulo-heptitol (15). The production of 15 from D-glycero-l-gulo-heptitol (13) was accompanied by a larger amount of 2,3:4,5:6,7-tri-O-isopropylidene-D-glycero-D-ido-heptitol (17) which, upon oxidation followed by hydrolysis, yielded D-glycero-D-ido-heptose (18). One of the two tri-O-isopropylidene derivatives obtained by acetonation of perseitol, 2,3:4,5:6,7-tri-O-isopropylidene-D-glycero-D-galacto-heptitol (19), yielded D-glycero-D-galacto-heptose (20). 相似文献
5.
Effects of auxin and cytokinin on cell growth and alkaloid production in cell suspension cultures of Thalictrum minus were examined in an attempt to increase the productivity of a medicinal compound, berberine. In Linsmaier and Skoog medium containing auxin such as 2,4-D (1 M), the cultured cells grew rapidly, producing little berberine. On the other hand, the berberine-producing activity was remarkably enhanced by simultaneous administration of auxin and cytokinin, although cell growth was inferior. In particular, for the combination of NAA (60 M) and 6-benzylaminopurine (10 M), the yield of berberine was as high as 20 mg/30 ml medium after 2 weeks of culture. Furthermore, most of the berberine produced by the cells was released into the liquid medium, in which an excess of berberine crystallized. The results of the present experiments are suggestive of an advantage in adopting a two-stage culture method for the production of berberine in fermentor systems.Abbreviations LS
Linsmaier and Skoog
- 2,4-D
2,4-dichlorophenoxyacetic acid
- NAA
1-naphthaleneacetic acid
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- BAP
6-benzylaminopurine 相似文献
6.
Cultured cells ofThalictrum flavum take up berberine exogenously added to medium against the concentration gradient. This uptake was temperature-dependent and sensitive to plasma membrane-bound ATPase inhibitors such as sodium orthovanadate and diethylstilbestrol, indicating that the process is mediated by an energy-requiring system. The time-course of pH-shift during berberine uptake suggests the participation of a berberine-proton antiport system in the berberine uptake by the cultured cells. In addition, the existence of a specific transport system was suggested by the competitive inhibition of berberine uptake by berberine analogues, coptisine and jatrorrhizine. 相似文献
7.
Toba T Murata K Futamura J Nakanishi K Takahashi B Takemoto N Tomino M Nakatsuka T Imajo S Goto M Yamamura T Miyake S Annoura H 《Bioorganic & medicinal chemistry》2012,20(9):2850-2859
A series of truncated analogs of α-galactosylceramide with altered ceramide moiety was prepared, and evaluated for Th2-biased response in the context of IL-4/IFN-γ ratio. Phytosphingosine-modified analogs including cyclic, aromatic and ethereal compounds as well as the C-glycoside analog of OCH (2) with their cytokine inducing profile are disclosed. 相似文献
8.
Shin-ichiro Kurimoto Kyoko Suzuki Mamoru Okasaka Yoshiki Kashiwada Olimjon K. Kodzhimatov Yoshihisa Takaishi 《Phytochemistry letters》2012,5(4):729-733
Five new eudesmane- (1–5), two new guaiane- (6 and 7) and one new germacrane-type (8) sesquiterpene lactone glucosides were isolated from the H2O-soluble fraction of the roots of Ferula varia. Their structures were elucidated by extensive spectroscopic analyses. The absolute configuration of 1 was determined by modified Mosher's method. 相似文献
9.
10.
Umezawa M Sakata C Tanaka N Kudo S Tabata M Takeda K Ihara T Sugamata M 《Cytokine》2008,43(2):105-109
The pathogenesis of endometriosis, a gynecologic disorder associated with infertility, appears to involve immune responses. However, the details involved have not been clarified. In this study, we analyzed expression levels of interleukin (IL)-6, IL-10, monocyte chemoattractant protein-1, eosinophil chemotactic protein, macrophage inflammatory protein-1α, and regulated on activation normal T cell expressed and secreted (RANTES) and CC chemokine receptor 1 in endometriotic lesions in a rat model in which endometrium is autotransplanted onto peritoneal tissue and found that they were remarkably increased, while those of IL-2, IL-4, and interferon-γ were not. These results were obtained in a rat model induced by autologous, not allogeneic, transplantation of endometrial epithelium to the peritoneum. Expression of these factors is consistent with that of endometriosis in humans. Therefore, this model may be useful in the investigation of the pathogenesis and treatment of endometriosis. 相似文献