• Archives of Pharmacal Research
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• v.29 no.4
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• pp.287-292
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• 2006

In this study, we isolated two new isorhamnetin glycosides, designated as nelumboroside A (3) and nelumboroside B (4), as well as the previously-characterized isorhamnetin glucoside (1) and isorhamnetin rutinoside (2), from the n-BuOH fraction of Nelumbo nucifera stamens. The structures of the two new compounds were then determined, using chemical and spectroscopic techniques. All isolated isorhamnetin glycosides 1-4 showed marked antioxidant activities in the DPPH, and $ONOO^-$ assays.

• Journal of the Korean Chemical Society
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• v.41 no.7
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• pp.357-361
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• 1997

8-Azaxanthine (1), 3-${\beta}$-D-ribofuranosyl-8-azaxanthine (2), 3-${\beta}$-D-ribofuranosyl-8-azaxanthine-5'-monophosphate (3), and 3-${\beta}$-D-ribofuranosyl-8-azaxanthine-5'-(3-pyridinylcarbonyl)monophosphate (4) were synthesized. The in vitro antitumor activities of the synthesized compounds against P388 mouse leukemia, FM3A mammary carcinoma, and U937 human histiocytic lymphoma cells were determined by MTT assay. 2 with unnatural N-3 and C-1' glycoside bond had activity against three tumor cell lines and $IC_{50}$s of these compounds were 0.05, 0.06, and 0.06 ${\mu}mol/mL$ against three tumor cell lines, respectively. But these compounds had no antibacterial activity. $IC_{50}$s against U937 human histiocytic lymphoma cells were verified with the structural modification: $IC_{50}$s of 1, 2, 3, and 4 were 0.33, 0.06, 0.25, and 0.33 ${\mu}mol/mL$, respectively.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.233-236
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• 2015

The flowers of Magnolia obovata were extracted with aqueous MeOH and fractionated into EtOAc, n-BuOH, and $H_2O$ fractination. Three alkyl glycosides were isolated from the EtOAc fraction through repeated silica gel and ODS column chromatography. The structures were identified to be 2-methylbutan-1-ol-${\beta}$-$\small{D}$-galacto-pyranoside (1), 2-methylbutan-1-ol-${\beta}$-$\small{D}$-glucopyranoside (2), and 2-methylpropan-1-ol-${\beta}$-$\small{D}$-glucopyranoside (3) on the basis of spectroscopic analyses such as fast atom bombardment mass spectrometry, infrared spectroscopy, 1D nuclear magnetic resonance (NMR) ($^1H$ and $^{13}C-NMR$), and 2D NMR (gCOSY, gHSQC, and gHMBC). These compounds were isolated for the first time from the flower of M. obovata in this study.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.121-126
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• 1985

Phytotron and field experiments were conducted to determine the influence of morphological growth stage and environmental temperature on synthesis and accumulation pattern of cyanogenic glycosides in sorghum cv. Pioneer 931 and Sioux at Munich technical university from 1979 to 1980. Various growth stages of sorghum plants were grown in phytotron at 4 different temperature regimes of 30/25, 25/20, 28/18 and 18/8 degree C with 35,000 Lux over 13-h days. The results obtained are summarized as follows: 1. Cyanogenic glycosides in sorghum plants were shown to have a great synthetic rate at early growth stages. The highest concentrations of hydrocyanic acid (HCN) were found at 2-leaf stage with 2384 and 1800ppm (DM basis) for Pioneer 931 and Sioux respectively. The contents of HCN were, however, however decreased markedly as morphological development, which shows a value of 173ppm (Pioneer 931) and 70ppm (Sioux) at heading stages. 2. Changes of hydrocyanic acid in sorghum plants were positive correlated with leaf weight ratio and leaf area ratio ($P{\leqq}0.1%$), while plant height shows a negative correlation with HCN contents ($P{\leqq}0.1%$). 3. Cyanogenic glycosides were accumulated in young plants mainly in leaves. During the late maturities, the contents of HCN in leaves and stalks were shown, however, a similar distribution. 4. Synthesis rates of cyanogenic glycosides were increased under high temperature. Accumulated hydrocyanic acid in the plants was, however declined when temperature exceeded 30 degree C. 5. Synthesis rates of cyanogenic glycosides were affected by nitrogen reductase activity (NRA). The concentration of hydrocyanic acid in sorghum plants was associated with increasing of nitrate-N accumulation.

• Journal of the Korean Chemical Society
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• v.42 no.5
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• pp.549-558
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• 1998

O-Antigenic part of Campylobacter jejuni gram negative bacteria was reported to consist of a repeated trisaccharide unit. The disaccharides, GlcNAc-Gal derivatives, as key intermediates for the synthesis of trisaccharide repeating units were synthesized. At the $\beta(1{\to}3)$ glycoside bond formation step between 3,4,6-tri-O-acctyl-2-deoxy-2-N-phthalimido-${\beta}$-D-glucopyranosyl bromide and galactosyl acceptors, high regioselectivities between 2, 3, and 4-OH groups of galactosyl acceptors were found. As a result, no further selective protection steps for OH groups of galactosyl acceptors was necessary, and more effective and compact synthetic scheme was achieved.

• Applied Biological Chemistry
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• v.41 no.2
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• pp.197-200
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• 1998

The MeOH extracts obtained from the flower petals of Carthamus tinctorius were solvent-fractionated with EtOAc, n-BuOH, and $H_2O$, successively. From the n-BuOH extract 2 flavonoid compounds were isolated through the repeated silica gel column chromatographies. From not only the results of physico-chemical data including HMBC but also the adaptation of acid hydrolysis, the chemical structures of the compounds were determined as $3-O-[{\beta}-D-glucopyranosyl(1{\rightarrow}2)\;{\beta}-D-glucopyranosyl]\;kaempferol$ and $3-O-[{\alpha}-L-rhamnopyranosyl(1{\rightarrow}6)\;{\beta}-D-glucopyranosyl]\;kaempferol$. The compounds exhibited $IC_{50}$ values in Grab2-Shc activity to be 43 and $47{\mu}g/ml$, respectively.

• Journal of the Korean Wood Science and Technology
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• v.34 no.6
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• pp.51-60
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• 2006

Juglans mandshurica barks were collected, extracted with acetone-$H_2O$ (7:3, v/v), fractionated with n -hexane, $CH_2Cl_2$, and EtOAc, and freeze dried to give some dark brown powder. The EtOA cand $H_2O$ soluble fractions were chromatographe d on a Sephadex LH-20 column using $H_2O$-MeOH and EtOH-hexane mixture as eluents. Spectrometric analysis such as NMR and MS, including TLC,were performed to characterize the structures of the isolated compounds. From the EtOAc and $H_2O$ soluble fractions, three flavanols (1~3), three flavonols (4~6) and five flavonol glycosides (7~11) were isolated and elucidated.

• Journal of Nutrition and Health
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• v.38 no.1
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• pp.48-55
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• 2005

Chitosan, which is a biopolymer, composed of glucosamine units linked by $\beta$-1, 4 glycoside bonds, is rich in shells of crustacean such as crabs and shrimps. Consumption of chitosan has been rapidly increased as a functional food. We examined effects of chitosan on the damages caused by lead (Pb) exposure in rats. Male Sprague-Dawley rats were divided into 8 groups (n = 64), then fed diets containing 3% cellulose (control) or 3% chitosan, each with 4 different lead doses (0 mg/d, 20 mg/d, 50 mg/d, and 100 mg/d) for 4 wks. Lead doses were given 3 times per week by oral administration. Blood lead levels in rats increased depending on the administered doses of lead. Rats fed chitosan diets showed lower blood lead concentration than did their respective controls. Effect of chitosan on the blood lead was more beneficial in rats exposed to lower lead (20 mg/d) than in rats exposed to higher lead (50 mg/d and 100 mg/d). Histological changes in erythrocytes and liver were also examined. Chitosan tended to reduce numbers of basophilic stippling erythrocytes and improve the histological liver changes in rats given various lead doses. The preventive effects of chitosan on liver damages were stronger in rats with higher lead than those with lower lead. These results indicate that chitosan has beneficial effects on both blood toxicological responses and histological damages of erythrocytes and liver induced by the administration of various lead doses.

• Korean Journal of Pharmacognosy
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• v.33 no.3 s.130
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• pp.194-199
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• 2002

The radix and folium of Eucommia ulmoides(Eucommiaceae) has been used for backache, atrophy of the leg and knee, enuresis, hypertension. In order to evaluate to quality of folium, we have been isolated a main compound as a standard compound, which was elucidated $quercetin-3-O-{\beta}-D-xylopyranosyl(l{\rightarrow}2)-{\beta}-D-glucopyranoside$ through it's physicochemical data and IR, FAB-Mass, $^{13}C-NMR$ and $^{1}H-NMR$ analysis. It was analyzed by HPLC system using 17% $CH_3CN$ as a solvent system. The amount of $quercetin-3-O-{\beta}-D-xylopyranosyl(l{\rightarrow}2)-{\beta}-D-glucopyranoside$ from Eucommiae folium was in the range of $0.056{\pm}0.022$ mg(n=7) and also from the results of analysis through seasonal variation$(June{\sim}October)$ September and October have been evaluated to be very high in it's content.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.77-78
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• 2003

A novel -1, 4-endoglucanase (EGase, EC 3.2.1.4) cDNA belonging to glycoside hydrolase family (GHF) 45 was cloned from the mulberry longicorn beetle, Apriona germari. The cDNA encoding EGase of A. germari (Ag-EGase) is 711 base pairs long with an open reading frame of 237 amino acid residues. The deduced protein sequence of Ag-EGase showed 54% and 48% identity to phytophagous beetle Phaedon cochleariae and termite Reticulitermes speratus hindgut symbiont, respectively. (omitted)