• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.110-117
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• 2008

Three kinds of prenylated flavonols, icariside I, icariside II, and icaritin, were isolated from an icariin hydrolysate and their effects on melanogenesis evaluated based on mushroom tyrosinase inhibition and quantifying the melanin contents in melanocytes. Although none of the compounds had an effect on tyrosinase activity, icariside II and icaritin both effectively inhibited the melanin contents with an $IC_{50}$ of 10.53 and $11.13{\mu}M$, respectively. Whereas icariside II was obtained from a reaction with ${\beta}$-glucosidase and cellulase, the icariin was not completely converted into icariside II. Thus, for the high-purity production of icariside II, the reaction was optimized using the response surface methodology, where an enzyme concentration of 5.0mg/ml, pH 7, $37.5^{\circ}C$, and 8 h reaction time were selected as the central conditions for the central composite design (CCD) for the enzymatic hydrolysis of icariin into icariside II using cellulase. Empirical models were developed to describe the relationships between the operating factors and the response (icariside II yield). A statistical analysis indicated that all four factors had a significant effect (p<0.01) on the icariside II production. The coefficient of determination $(R^2)$ was good for the model (0.9853), and the optimum production conditions for icariside II was an enzyme concentration of 7.5mg/ml, pH 5, $50^{\circ}C$, and 12 h reaction time. A good agreement between the predicted and experimental data under the designed optimal conditions confirmed the usefulness of the model. A laboratory pilot scale was also successful.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.140-143
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• 1998

From the methanol extract of the whole part of Sagittaria trifolia ergosterol peroxide, icariside D2. Thalictoside and 4-nitrophenyl $\{beta}$-D-glucopyranoside wer e isolated and their structures were identified by the physico-chemical and spectral data. This is the first report of these compounds from S. trifolia.

• Natural Product Sciences
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• v.26 no.2
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• pp.151-157
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• 2020

Extensive column chromatography separation of the MeOH extract from the aerial parts of Phyllanthus urinaria afforded seventeen compounds (1 - 17). The structures of the compounds were elucidated by physicochemical and spectroscopic methods to be 5'-β-D-glucopyranosyloxyjasmonic butyl ester (1), (+)-cucurbic acid (2), dendranthemoside B (3), boscialin 4'-O-β-D-glucoside (4), 4,5-dihydroblumenol A (5), (6R,9R)-megastigman-4-ene-9,13-diol (6), (3S,5R,6S,9R)-3,6-dihydroxy-5,6-dihydro-β-ionol (7), (6S,9R)-roseoside (8), mallophenol B (9), icariside B₅ (10), corchoinoside B (11), canangaionoside (12), 5,6-epoxy-3-hydroxy-7-megastigmen-9-one (13), icariside B₂ (14), (7E)-2β,3β-dihydroxy-megastigm-7-en-9-one (15), betulalbuside A (16), and loliolide (17). The compounds 1, and 3 - 16 were isolated for the first time from this plant. The absolute stereochemistry of compound 1 was newly determined. The isolated compounds were tested for cytotoxic activity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay, but all the compounds showed weak cytotoxic activities.

• Natural Product Sciences
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• v.15 no.2
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• pp.90-95
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• 2009

Phytochemical investigation of the MeOH extract of the leaves of Nelumbo nucifera resulted in the isolation of five norsesquiterpenes, four flavonoids, two triterpenes and one alkaloid. Their chemical structures were characterized by spectroscopic methods to be (E)-3-hydroxymegastigm-7-en-9-one (1), (3S,5R,6S,7E)- megastigma-7-ene-3,5,6,9-tetrol (2), dendranthemoside B (3), icariside $B_2$ (4), sedumoside $F_1$ (5), luteolin (6), quercetin 3-0-${\beta}$-D-glucuronide (7), quercetin 3-0-${\beta}$-D-glucoside (8), isorhamnetin 3-0-rutinoside (9), alphitolic acid (10), maslinic acid (11), and N-methylasimilobine (12). Norsesquiterpenoids (1-5) and triterpenes (10-11) were isolated for the first time from this plant. Compounds 6 and 10-12 exhibited considerable cytotoxicity against four human cancer cell lines in vitro using a SRB bioassay.

• Korean Journal of Pharmacognosy
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• v.37 no.3
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• pp.125-129
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• 2006

The chromatographic separation of n-BuOH extract of the aerial parts of Prunus padus (Rosaceae) led to the isolation of two cerebrosides, and six phenolic compounds. Their structure were identified to be pinelloside (1), soyacebroside I (2), $quercetin-3-O-{\beta}-D-galactopyranoside$ (3), nudiposide (4), (+)-isolarisiresinol $9'-O-{\beta}-D-xylopyroanoside$ (5), khaephuoside A (6) and icariside F2(7) by physicochemical and spectroscopic methods. The compounds $1,5{\sim}7$ are first isolated from the genus Prunus.

• Natural Product Sciences
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• v.19 no.3
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• pp.221-226
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• 2013

Phytochemical investigation of the 80% MeOH extract from the leaves of Allium victorialis var. platyphyllum resulted in the isolation of seventeen compounds; two terpenes, three norsesquiterpenes, one furofuran lignan, and eleven phenolic derivatives. Their chemical structures were characterized by spectroscopic methods to be trans-phytol (1), phytene-1,2-diol (2), icariside B2 (3), (6S,9S)-roseoside (4), sedumoside G (5), pinoresinol-4-O-glucoside (6), 2-methoxy-2-(4'-hydroxyphenyl)ethanol (7), 2-hydroxy-2-(4'-hydroxyphenyl)ethanol (8), Benzyl ${\beta}$-D-glucopyranoside (9), methyl ferulate (10), trans-ferulic acid (11), methyl-p-hydroxycinnamate (12), glucosyl methyl ferulate (13), linocaffein (14), siringin (15), 2-(4-hydroxy-3-methoxyphenyl)-ethyl-O-${\beta}$-Dglucopyranoside (16), and pseudolaroside C (17). All compounds were isolated for the first time from this plant.

• Natural Product Sciences
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• v.20 no.2
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• pp.95-101
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• 2014

Five lignan glycosides, seven megastigmane glycosides, and seven phenolic compounds were isolated by repeated column chromatography from the MeOH extract of Salsola komarovii. Their structures were determined to be lariciresinol-9-O-${\beta}$-$\small{D}$-glucopyranoside (1), alangilignoside C (2), conicaoside (3), (+)-lyoniresinol 9'-O-${\beta}$-$\small{D}$-glucopyranoside (4), (8S,8'R,7'R)-9'-[(${\beta}$-glucopyranosyl)oxy]lyoniresinol (5), blumenyl B ${\beta}$-$\small{D}$-glucopyranoside (6), blumenyl A ${\beta}$-$\small{D}$-glucopyranoside (7), staphylionoside D (8), icariside $B_2$ (9), (6R,9S)-3-oxo-${\alpha}$-ionol ${\beta}$-$\small{D}$-glucopyranoside (10), 3-oxo-${\alpha}$-ionol 9-O-${\beta}$-$\small{D}$-apiofuranosyl-($1{\rightarrow}6$)-${\beta}$-$\small{D}$-glucopyranoside (11), blumenol B 9-O-${\beta}$-$\small{D}$-apiofuranosyl-($1{\rightarrow}6$)-${\beta}$-$\small{D}$-glucopyranoside (12), benzyl 6-O-${\beta}$-$\small{D}$-apiofuranosyl-${\beta}$-$\small{D}$-glucopyranoside (13), canthoside C (14), tachioside (15), isotachioside (16), biophenol 2 (17), 2-(3,4-dihydroxy)-phenyl-ethyl-${\beta}$-$\small{D}$-glucopyranoside (18), and cuneataside C (19) by spectroscopic methods. All the isolated compounds 1 - 19 were reported from this source for the first time. Compounds 2, 3 and 6 upregulated NGF secretion to $118.8{\pm}3.6%$, $128.2{\pm}9.3%$ and $111.1{\pm}7.1%$ without significant cell toxicity.

• Journal of Microbiology and Biotechnology
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• v.33 no.12
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• pp.1606-1614
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• 2023

Biochemical gut metabolism of dietary bioactive compounds is of great significance in elucidating health-related issues at the molecular level. In this study, a human gut bacterium cleaving C-C glycosidic bond was screened from puerarin conversion to daidzein, and a new, gram-positive C-glycoside-deglycosylating strain, Dorea sp. MRG-IFC3, was isolated from human fecal sample under anaerobic conditions. Though MRG-IFC3 biotransformed isoflavone C-glycoside, it could not metabolize other C-glycosides, such as vitexin, bergenin, and aloin. As evident from the production of the corresponding aglycons from various 7-O-glucosides, MRG-IFC3 strain also showed 7-O-glycoside cleavage activity; however, flavone 3-O-glucoside icariside II was not metabolized. In addition, for mechanism study, C-glycosyl bond cleavage of puerarin by MRG-IFC3 strain was performed in D₂O GAM medium. The complete deuterium enrichment on C-8 position of daidzein was confirmed by ¹H NMR spectroscopy, and the result clearly proved for the first time that daidzein is produced from puerarin. Two possible reaction intermediates, the quinoids and 8-dehydrodaidzein anion, were proposed for the production of daidzein-8d. These results will provide the basis for the mechanism study of stable C-glycosidic bond cleavage at the molecular level.