• Archives of Pharmacal Research
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• 제28권2호
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• pp.195-202
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• 2005

Free radicals and reactive oxygen species (ROS) caused by UV exposure or other environmental factors are critical players in cellular damage and aging. In order to develop a new antiphotoaging agent, this work focused on the antioxidant effects of the extract of tinged autumnal leaves of Acer palmatum. One compound was isolated from an ethyl acetate soluble fraction of the A. palmatum extract using silica gel column chromatography. The chemical structure was identified as apigenin-8-C-beta-D-glucopyranoside, more commonly known as vitexin, by spectral analysis including LC-MS, FT-IR, UV, $^{1}H-$, and $^{13}C-NMR$. The biological activities of vitexin were investigated for the potential application of its anti-aging effects in the cosmetic field. Vitexin inhibited superoxide radicals by about $70\%$ at a concentration of $100\;{\mu}g/mL$ and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals by about $60\%$ at a concentration of $100\;{\mu}g/mL$. Intracellular ROS scavenging activity was indicated by increases in dichlorofluorescein (DCF) fluorescence upon exposure to UVB $20\;mJ/cm^2$ in cultured human dermal fibroblasts (HDFs) after the treatment of vitexin. The results show that oxidation of 5-(6-)chloromethyl-2',7'-dichlo-rodihydrofluorescein diacetate ($CM-H_{2}DCFDA$) is inhibited by vitexin effectively and that vitexin has a potent free radical scavenging activity in UVB-irradiated HDFs. In ROS imaging using a confocal microscope we visualized DCF fluorescence in HDFs directly. In conclusion, our findings suggest that vitexin can be effectively used for the prevention of UV-induced adverse skin reactions such as free radical production and skin cell damage.

• 한국식품영양과학회지
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• 제21권4호
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• pp.423-427
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• 1992

Penicillium verruculosum을 xylan을 함유한 액체배지에서 26일간 배양하면서 xylan 분해활성도를 비롯한 몇 가지 변화를 관찰하였다. Xylan과 PNPX 분해활성도는 단백질량의 증가와 함께 배양 8일까지 급격히 증가하였으나 배양액 중의 환원당의 변화와는 비례하지 않았다. 배양 12일째의 배양상징 액을 탄소원으로서 cell-obiose octaacetate를 가한 배양상징액과 함께 전기영동하였을때 서로 다른 단백질 분포양상을 보였으며 본 배양상징액에 있어 섬유소 성분들에 대한 분해활성도는 거의 나타나지 않은 반면 xylan에 대해서는 매우 높은 활성도를 나타냈다. 배양 상징 액에 xylan을 가했을 때 반응 생성물로서 xylose와 xylobiose를 비롯하여 소당류들이 생성됨으로서 endo-type의 분해활성도로 추정 되었으며 이 때 xylobiose가 가장 많은 비율을 차지했다. Xylan과 PNPX분해 활성도에 대한 배양 상징액의 최적온도는 각각 50~6$0^{\circ}C$와 60~7$0^{\circ}C$였으며 최적pH는 각각 3.0-4.0과 4.0-5.0이었다.

• Journal of Ginseng Research
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• 제36권4호
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• pp.418-424
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• 2012

This study focused on the enzymatic biotransformation of the major ginsenoside Rb1 into Rd for the mass production of minor ginsenosides using a novel recombinant ${\beta}$-glucosidase from Flavobacterium johnsoniae. The gene (bglF3) consisting of 2,235 bp (744 amino acid residues) was cloned and the recombinant enzyme overexpressed in Escherichia coli BL21(DE3) was characterized. This enzyme could transform ginsenoside Rb1 and gypenoside XVII to the ginsenosides Rd and F2, respectively. The glutathione S-transferase (GST) fused BglF3 was purified with GST-bind agarose resin and characterized. The kinetic parameters for ${\beta}$-glucosidase had apparent $K_m$ values of $0.91{\pm}0.02$ and $2.84{\pm}0.05$ mM and $V_{max}$ values of $5.75{\pm}0.12$ and $0.71{\pm}0.01{\mu}mol{\cdot}min^{-1}{\cdot}mg$ of $protein^{-1}$ against p-nitrophenyl-${\beta}$-D-glucopyranoside and Rb1, respectively. At optimal conditions of pH 6.0 and $37^{\circ}C$, BglF3 could only hydrolyze the outer glucose moiety of ginsenoside Rb1 and gypenoside XVII at the C-20 position of aglycon into ginsenosides Rd and F2, respectively. These results indicate that the recombinant BglF3 could be useful for the mass production of ginsenosides Rd and F2 in the pharmaceutical or cosmetic industry.

• 한국식품과학회지
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• 제47권2호
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• pp.170-175
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• 2015

본 연구에서는 국산배의 기능학적 우수성 증명을 위해 국산배로부터 생리활성 화합물을 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성획분을 대상으로 Sephadex LH-20 column chromatography와 ODS-HPLC를 이용하여 순차적으로 정제를 행하여 2종의 화합물을 단리하였다. 단리된 화합물 1과 2는 MS 및 NMR 분석을 통하여 각각 quercetin 3-O-${\beta}$-Dglucopyranoside(화합물 1)와 3,5,6,7,8,3',4'-heptahydroxyflavan [(-)-dulcisflavan, 화합물 2)]으로 동정되었다. 단리된 화합물 1은 동양배로부터, 그리고 화합물 2는 배로부터 처음 동정된 화합물이다. 본 연구결과가 국산배의 기능학적 우수성 증명을 위한 기초자료로 활용되길 기대한다.

• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1705-1713
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• 2012

A gene encoding ${\beta}$-glucosidase was cloned from Weissella cibaria 37, an isolate from human feces. Sequence analysis showed that the gene could encode a protein of 415 amino acids in length, and the translated amino acid sequence showed homology (34-31%) with glycosyl hydrolase family 1 ${\beta}$-glucosidases. The gene was overexpressed in E. coli BL21(DE3) using pET26b(+) and a 50 kDa protein was overproduced, which matched well with the calculated size of the enzyme, 49,950.87 Da. Recombinant ${\beta}$-glucosidase was purified by using a his-tag affinity column. The purified ${\beta}$-glucosidase had an optimum pH and a temperature of 5.5 and $45^{\circ}C$, respectively. Among the metal ions (5mM concentration), $Ca^{2+}$ slightly increased the activity (108.2%) whereas $Cu^{2+}$ (46.1%) and $Zn^{2+}$ (56.7%) reduced the activity. Among the enzyme inhibitors (1 mM concentration), SDS was the strongest inhibitor (16.9%), followed by pepstatin A (45.2%). The $K_m$ and $V_{max}$ values of purified enzyme were 4.04 mM and 0.92 ${\mu}mol/min$, respectively, when assayed using pNPG (p-nitrophenyl-${\beta}$-D-glucopyranoside) as the substrate. The enzyme liberated reducing sugars from carboxymethyl cellulose (CMC).

• Natural Product Sciences
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• 제22권2호
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• pp.111-116
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• 2016

Phytochemical investigation of the stems of Pueraria lobata (Wild) Ohwi (Leguminosae), led to the isolation of eighteen known compounds: ${\beta}$-amyrone (1), (+)-pinoresinol (2), (+)-syringaresinol (3) $(+)-syringaresinol-O-{\beta}-{\small{D}}-glucoside$ (4), (+)-lariciresinol (5), (-)-tuberosin (6), naringenin (7), liquiritigenin (8), isoliquiritigenin (9) genistein (10), daidzein (11) daidzin (12) daidzein 4',7-diglucoside (13) 2,4,4'-trihydroxy deoxybenzoin (14), S-(+)-1-hydroxy-3-(4-hydroxyphenyl)-1-(4-hydroxy-2-methoxy-phenyl)propan-2-one (15), methyl $2-O-{\beta}-{\small{D}}-glucopyranosylbenzoate$ (16), pyromeconic acid $3-O-{\beta}-{\small{D}}-glucopyranoside$ 6'- (O-4''-hydroxy-3-methoxybenzoate) (17), and allantion (18). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of those data with previously published results. The effects of isolated compounds on mushroom tyrosinase enzymatic activity were screened. The results indicated that, chloroform extract of P. lobata stems turned out to be having tyrosinase inhibitory effect, and only compounds 5, 8, 9, and 11 showed enzyme inhibitory activity, with $IC_{50}$ values of $21.49{\pm}4.44$, $25.24{\pm}6.79$, $4.85{\pm}2.29$, and $17.50{\pm}1.29{\mu}M$, respectively, in comparison with these of positive control, kojic acid ($IC_{50}\;12.28{\pm}2.72{\mu}M$). The results suggest that P. lobata stems extract as well as its chemical components may represent as potential candidates for tyrosinase inhibitors.

• 생약학회지
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• 제44권3호
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• pp.230-234
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• 2013

In the course of screening for antioxidant compounds by measuring the DPPH radical scavenging activity, a total extract of the aerial part of Trigonotis peduncularis (Boraginaceae) was found to show potent DPPH radical scavenging activity. Subsequent activity-guided fractionation of the methanolic extract of T. peduncularis led to the isolation of seven compounds, kaempferol (1), quercetin (2), trigonotin A (3), astragalin (4), trigonotin C (5), kaempferol-3-O-${\alpha}$-L-rhamnopyranosyl(1${\rightarrow}$6)-${\beta}$-D-glucopyranoside (6), and rutin (7) from the active ethyl acetate soluble fraction. Their structures were elucidated by spectroscopic studies. Among seven compounds, compounds 1, 2, 4, 6 and 7 were isolated for the first time from this plant, and compounds 2 and 7 showed the significant DPPH free radical scavenging activities.

• 생약학회지
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• 제36권3호통권142호
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• pp.245-251
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• 2005

Phytochemical examination of the barks of Actinidia arguta led to the isolation of five flavonoids. Structures of compounds were elucidated as catechin (1), (-)-epicatechin (2), quercetin (3), $quercetin-3-O-{\beta}-D-glucopyranoside$ (4), $quercetin-3-O-{\beta}-D-galactopyranoside$ (5) by comparison with previously reported spectral evidences. To investigate the anti-oxidative effect and nitric oxide (NO) production inhibitory activity of these compounds, DPPH radical scavenging activity and nitric oxide production inhibitory activity in $IFN-{\gamma}$, LPS stimulated RAW 264.7 cell were examined. The $IC_{50}s$ were determinied as follows : $1\;$IC_{50}=26.61\;{\mu}g/ml$, $2\;IC_{50}=25.30\;{\mu}g/ml$, $3\;IC_{50}=20.41\;{\mu}g/ml$, $4\;IC_{50}=18.23\;{\mu}g/ml$ , $5\;IC_{50}=30.46\;{\mu}g/ml$, $6\;IC_{50}=28.0;{\mu}g/ml$, $7\;IC_{50}=27.24\;{\mu}/ml$. These NO production inhibitory effects were significantly different compared with the positive control, L-NMMA $(IC_{50}=20.77\;{\mu}g/ml)$, respectively. Compound $1\;(IC_{50}=6.19\;{\mu}g/ml)$, $2\;(IC_{50}=8.98\;{\mu}g/ml)$, $3\;(IC_{50}=7.30\;{\mu}g/ml)$ and $4\;(IC_{50}=7.64\;{\mu}g/ml)$ also showed potent antioxidative activities similar level to ascorbic acid $(IC_{50}=9.22\;{\mu}g/ml)$. These results suggest that barks of A. arguta have a potent anti-oxidative and anti-inflammatory activity.

• Food Science and Biotechnology
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• 제17권6호
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• pp.1165-1170
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• 2008

The deposition of the amyloid $\beta}$ ($A{\beta}$)-peptide following proteolytic processing of amyloid precursor protein (APP) by $\beta$-secretase (BACE1) and $\gamma$-secretase is critical feature in the progress of Alzheimer's disease (AD). Consequently, BACE1, a key enzyme in the production of $A{\beta}$, is a prime target for therapeutic intervention in AD. In the course of searching for BACE1 inhibitors from natural sources, the ethyl acetate fraction of Petasites japonicus showed potent inhibitory activity. Two BACE1 inhibitors quercetin (QC) and kaempferol 3-O-(6"-acetyl)-$\beta$-glucopyranoside (KAG) were isolated from P. japonicus by activity-guided purification. QC, in particular, non-competitively attenuated BACE1 activity with $IC_{50}$ value of $2.1{\times}10^{-6}\;M$ and $K_i$ value of $3.7{\times}10^{-6}\;M$. Both compounds exhibited less inhibition of $\alpha$-secreatase (TACE) and other serine proteases including chymotrypsin, trypsin, and elastase, suggesting that they ere relatively specific and selective inhibitors to BACE1. Furthermore, both compounds significantly reduced the extracellular $A{\beta}$ secretion in $APP_{695}$-transfected B103 cells.

• Food Science and Biotechnology
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• 제15권4호
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• pp.617-624
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• 2006

Various plant phenolics were assessed for (${\beta}$-secretase (BACE1) inhibitory activity in order to screen for anti-dementia agents. Among 39 phenolics, eight compounds, 1,2,3-trigalloyl glucopyranoside, acetonyl geraniin, euphorscopin, furosine, helioscopinin A, helioscopinin B, jolkinin, and rugosin E exhibited strong inhibition of BACE1 with $IC_{50}$ values of $5.87{\times}10^{-8}-54.93{\times}10^{-6}\;M$. Among them, rugosin E was the most potent ($IC_{50}$ $5.87{\times}10^{-8}\;M$). The active compounds were shown to be non-competitive inhibitors by Dixon plot. All the phenolic BACE1 inhibitors except furosin also suppressed prolyl endopeptidase (PEP) activity. However, these phenolic compounds caused less inhibition of ${\alpha}$-secretase (tumor necrosis factor a converting enzyme; TACE) and no significant inhibition of other serine proteases such as trypsin, chymotrypsin, and elastase was seen, demonstrating that they are relatively specific to both BACE1 and PEP. No significant structure-activity relationships were found.