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71.
From the polar portion of the methanolic extract of cumin (fruit of Cuminum cyminum L.), two sesquiterpenoid glucosides, cuminoside A and B, and two alkyl glycosides were isolated together with five known compounds. Their structures were established as (1S,5S,6S,10S)-10-hydroxyguaia-3,7(11)-dien-12,6-olide beta-D-glucopyranoside, (1R,5R,6S,7S,9S,10R,11R)-1,9-dihydroxyeudesm-3-en-12,6-olide 9-O-beta-D-glucopyranoside, methyl beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside and ethane-1,2-diol 1-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside, respectively. 相似文献
72.
Eight glycosides of 2-C-methyl-D-erythritol (1) were isolated from the fruit of anise, and their structures were clarified as 1-O-beta-D-glucopyranoside, 3-O-beta-D-glucopyranoside, 4-O-beta-D-glucopyranoside, 1-O-beta-D-fructofuranoside, 3-O-beta-D-fructofuranoside, 4-O-beta-D-fructofuranoside, 1-O-beta-D-(6-O-4-hydroxybenzoyl)-glucopyranoside and 1-O-beta-D-(6-O-4-methoxybenzoyl)-glucopyranoside of 2-C-methyl-D-erythritol (2-9), respectively. Furthermore, 2 and 4 were isolated from the fruit of coriander, and 2, 3 and 4 were isolated from the fruit of cumin. Though the phosphate of 1 was known to be one of the first precursors of isoprenoids in the non-mevalonate pathway, and 1 is considered to be a common constituent in Umbelliferous plants, the glycosides of 1 are found for the first time. 相似文献
73.
Improvement of phenylethanoid glycosides production by a fungal elicitor in cell suspension culture of Cistanche deserticola 总被引:4,自引:0,他引:4
When, on the 15th day of growth, an elicitor from Fusarium solani was added at 40 mg l–1 to Cistanche deserticola cell suspension cultures, the contents of echinacoside, acteoside and total phenylethanoid glycosides (PeGs) in cultured cells all increased over the next 27 d by over 100% to 15 mg g–1 dry wt, 9 mg g–1 dry wt and 57 mg g–1 dry wt, respectively. The final biomass (1.3 mg dry wt ml–1) was not affected. 相似文献
74.
Takashi Fujita Hitoshi Hatamoto Mari Miyamoto Taisuke Iwasaki Shin-ichi Takafuji 《Biotechnology letters》1998,20(11):1057-1061
Cell suspensions derived from Acer nikoense callus, not containing (S)-rhododendrol, converted 4-(p-hydroxyphenyl)-2- butanone into (R)-, (S)-rhododendrol and their glycosides. (R)- and (S)-rhododendrol formed was only detected in the culture medium and their glycosides only in the cells. The former compound disappeared within a short time and the latter one also tended to decrease during prolonged culture. Quantitative analysis of rhododendrol glycosides in the callus showed that most of them were (S)-rhododendrol 2-O--D-glucopyranoside and its content was much lower than that of the original plants. © Rapid Science Ltd. 1998 相似文献
75.
76.
Four new glycosides, including one anthraquinone glycoside (1), one naphthalene glycoside (2), and two naphthopyrone glycosides (3–4), with 10 known compounds (5–14) were isolated from the seeds of Cassia obtusifolia L. The new structures were determined by spectroscopic analysis and chemical transformations. 相似文献
77.
Three new compounds including one C21-steroidal glycoside, one methylglycoside, and one neolignan, named as Deoxyamplexicogenin A-3-O-yl-4-O-(4-O-α-l-cymaropyranosoyl-β-d-digitoxopyranosoyl)-β-d-canaropyranoside (1), Methyl-O-α-l-cymaropyranosoyl-(1 → 4)-β-D-digitoxopyranoside (2), and (+)-(7S, 8R, 7′E)-5-hydroxy-3, 5′-dimethoxy-4′, 7-epoxy-8, 3′-neolign-7′-ene-9, 9′-diol 9′-ethyl ether (3), respectively, were isolated from the roots of Cynanchum stauntonii. The structure elucidations were achieved by in-depth spectroscopic examination, mainly including the experiments and analyses of multiple 1D- and 2D-NMR and HRESIMS and CD analysis and qualitative chemical tests. Cytotoxicity activities of compounds 1–3 were evaluated against five tumor cell lines (HCT-8, Bel-7402, BGC-823, A549, and A2780) in cell based assays where they were found to be inactive. 相似文献
78.
Phytochemical investigation of the aerial parts of Lysimachia clethroides led to the isolation of a new acylated flavonol glycoside (1) and a new δ-truxinate derivative (2), together with three known acylated flavonol glycosides. The structures of the new compounds were determined by spectroscopic methods and chemical evidence as quercetin-3-O-β-d-(6-O-Z-p-coumaroyl)glucopyranoside (1) and monomethyl 3,3′,4,4′-tetrahydroxy-δ-truxinate (2), respectively. All of the isolates were evaluated for their in vitro inhibitory activity against aldose reductase. 相似文献
79.
Masatomo So Yuto Kimura Keiichi Yamaguchi Toshihiko Sugiki Toshimichi Fujiwara Cesar Aguirre Kensuke Ikenaka Hideki Mochizuki Yasushi Kawata Yuji Goto 《Protein science : a publication of the Protein Society》2021,30(8):1701
Amyloid fibril formation is associated with various amyloidoses, including neurodegenerative diseases such as Alzheimer''s and Parkinson''s diseases. Amyloid fibrils form above the solubility of amyloidogenic proteins or peptides upon breaking supersaturation, followed by a nucleation and elongation mechanism, which is similar to the crystallization of solutes. Many additives, including salts, detergents, and natural compounds, promote or inhibit amyloid formation. However, the underlying mechanisms of the opposing effects are unclear. We examined the effects of two polyphenols, that is, epigallocatechin gallate (EGCG) and kaempferol‐7─O─glycoside (KG), with high and low solubilities, respectively, on the amyloid formation of α‐synuclein (αSN). EGCG and KG inhibited and promoted amyloid formation of αSN, respectively, when monitored by thioflavin T (ThT) fluorescence or transmission electron microscopy (TEM). Nuclear magnetic resonance (NMR) analysis revealed that, although interactions of αSN with soluble EGCG increased the solubility of αSN, thus inhibiting amyloid formation, interactions of αSN with insoluble KG reduced the solubility of αSN, thereby promoting amyloid formation. Our study suggests that opposing effects of polyphenols on amyloid formation of proteins and peptides can be interpreted based on the solubility of polyphenols. 相似文献
80.
Two sterylglycosides have been isolated from rice plants and identified as β-d-glucopyranosyl (1 → 3)-sitosterol and β-d-glucopyranosyl(1 相似文献