• 생명과학회지
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• 제28권1호
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• pp.43-49
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• 2018

Chrysoeriol은 alfalfa에서 주로 발견되는, 식물계에 많이 분포하고 있는 flavone으로 전통의학에서 소화불량, 천식, 비뇨기계 이상의 치료에 사용되어 왔다. 최근의 연구에서는 항염증 효과가 있는 것으로 밝혀졌으나 항산화 효과에 대한 분석은 없었다. 본 연구에서는 chrysoeriol의 항산화 효과와 그 분자적 기전을 RAW 264.7 cell에서 세포생존율, reactive oxygen species (ROS)와 Western blot분석을 통해 알아보고자 하였다. Chrysoeriol은 lipopolysaccharide(LPS)에 의해 발생한 ROS를 세포독성없이 농도의존적으로 제거하였다. 그리고 항산화효과를 보이는 2상 효소 중 하나인 heme oxygenase (HO)-1의 발현을 강하게 유도하였고, 그와 동시에 전사인자인 Nrf2의 핵내 이동도 촉진하는 것으로 밝혀졌다. 특히, 산화스트레스에 대한 세포내 산화환원항상성 유지에 중요한 역할을 하고 있는 것으로 알려진 mitogen activated protein kinase (MAPK)와 phosphoinositide 3-kinase (PI3K)의 분석결과, chrysoeriol은 extracellular signal regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK)와 p38의 인산화를 통해 HO-1의 발현을 유도하는 것으로 나타났다. HO-1에 의한 항산화 효과를 확인하기 위하여 chrysoeriol을 전처리한 후 t-BHP에 의한 산화 스트레스에 세포를 노출시킨 결과, chrysoeriol 처리에 의해 세포사멸이 줄어드는 것을 확인하였고, HO-1의 유도제와 억제제의 처리에 따라 세포생존율 또한 조절되는 것을 확인할 수 있었다. 따라서, chrysoeriol은 HO-1의 발현을 유도하여 항산화 효과를 높이고 이것은 Nrf2/MAPK 신호전달 체계에 의한다는 것을 알 수 있었다.

• BMB Reports
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• 제53권7호
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• pp.379-384
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• 2020

Exposure to Ultraviolet (UV) light induces photoaging of skin, leading to wrinkles and sunburn. The perennial herb Humulus japonicus, widely distributed in Asia, is known to have anti-inflammatory, antimicrobial, and antioxidant effects. However, the physiological activities of isolated compounds from H. japonicus have rarely been investigated. This study focused on the isolation of active compounds from H. japonicus and the evaluation of their effects on photoaging in UVB-irradiated human fibroblast (Hs68) cells. When the extract and four fractions of H. japonicus were treated respectively in UVB-irradiated Hs68 cells to investigate anti-photoaging effects, the ethyl acetate (EtOAc) fraction showed the strongest inhibitory effect on MMP1 secretion. From EtOAc fraction, we isolated luteolin-8-C-glucoside (1), apigenin-8-C-glucoside (2), and luteolin-7-O-glucoside (3). These compounds suppressed UVB-induced MMP-1 production by inhibiting the phosphorylation of the mitogen-activated protein kinases (MAPKs) and activator protein-1 (AP-1). When the antioxidant activity of the compounds were estimated by conducting western blot, calculating the bond dissociation energies of the O-H bond (BDE) at different grade, and measuring radical scavenging activity, we found luteolin-8-C-glucoside (1) showed the strongest activity on the suppression of UVB-induced photoaging. These results demonstrate the inhibitory effect of three flavone glycosides derived from H. japonicus on MMP-1 production, MAPK and AP-1 signaling, and oxidative stress; this could prove useful in suppressing UVB induced photoaging.

• 한국식품과학회지
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• 제38권2호
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• pp.279-283
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• 2006

홍화씨의 폴리페놀 성분들이 HMGR 활성, LDL-oxidation과 Hep3B 세포로부터의 Apo A1 분비능에 미치는 영향을 조사하였다. 홍화씨 성분은 matairesinol(lignan), acacetin(flavone) 및 N-feruloylserotonin과 matairesinol의 대사산물인 enterolactone을 사용하였다. 그 결과, HMCR 저해활성은 mevastatin이 53%로 가장 높은 활성을 나타내었고 다음은 홍화씨 serotronin 유도체인 N-feruloylserotonin이 45%의 저해활성을 보여 홍화씨 폴리페놀 중에서는 가장 높은 활성을 보였으며 genistein은 35%의 활성을 보인 반면 나머지는 활성이 거의 미미하였다. N-feruloylserotonin의 활성은 용량 의존적 반응을 나타내었다. LDL 산화 억제효과는 사용한 모든 홍화씨 폴리페놀성분에서 나타났는데, 특히 N-feruloylserotonin에서 가장 강한 활성을 보였고 역시 용량 의존적 반응을 보였다. Hep3B에서의 Apo A1 분비능은 mevastatin에서 가장 높았고 enterolactone, genistein 및 ${\beta}-estradiol$에서 분비 증강활성을 나타내었다. 이상의 결과들로 미루어 볼 때, 홍화씨 폴리페놀 성분들은 콜레스테를 생합성과 LDL의 산화를 억제시킴으로서 지질대사 및 동맥경화 개선에 기여할 수 있을 것으로 사료된다.

• Natural Product Sciences
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• 제6권4호
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• pp.170-178
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• 2000

Flavonoids are natural polyphenolic compounds widely distributed in plant kingdom. Although many flavonoids were found to show anti-inflammatory activity in vitro and in vivo, the potency of anti-inflammatory activity was not enough for a clinical trial. Thus, a search for finding potential flavonoid molecules is continuing. In this review, in vivo anti-inflammatory activity of various flavonoid derivatives is summarized mainly based on the results obtained in authors' laboratories. Among them, several biflavonoids such as amentoflavone and ginkgetin were found to possess anti-inflammatory activity on animal models of acute/chronic inflammation comparable to nonsteroidal and steroidal anti-inflammatory drugs currently used. In respect of their action mechanisms, the effects on arachidonic acid metabolism and nitric oxide production were described. Some flavonoids directly inhibit cyclooxygenase and/or lipoxygenase. Biflavones such as ochnaflavone and ginkgetin are inhibitors of phospholipase $A_2$. In recent studies, certain flavonoids were also found to suppress cyclooxygenase-2 and inducible nitric oxide synthase expression induced by inflammatory stimuli. Therefore, it is suggested that anti-inflammatory activity of the certain flavonoids (mainly flavones, flavonols and biflavonoids) may be mediated by direct inhibition of arachidonic acid metabolizing enzymes as well as suppression of the enzyme expression involved in inflammatory responses.

• Preventive Nutrition and Food Science
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• 제3권4호
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• pp.315-319
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• 1998

Previously, the methanolic extract of Paeonia moutan seeds was found to potently inhibit soybean lipoxy-genase (SLO). Hence to isolate SLO inhibitor, the defattd methaniolic extract of the seeds was consecutively partitioned wiht ether, ethyl acetate,n-butanol ,adn water. The ether souble fraction showing strong inhibitory activity against SLO was further fractionated into a strongly acidic, a weakly acidic, and a neutral fractions. The strongly acidic components of the ether extract were successively subjected to chromatography on a silica gel, Sephadex LH-20, and preparative HPLC. Four phenolic compounds were isolated , and twio of them showing a strong SLO inhibition activity were identified as luteolin (IC50=2.32$\mu\textrm{g}$/ml) and 5,6,4'-trihydroxy-7,3'- dimethoxylflavone (IC50=0.31$\mu\textrm{g}$/ml) by UV, IR, 1H-& 13C-NMR, and MS spectroscopy. In addition, two flavonoids showed significantly antioxidative activity as strong as that of of $\alpha$-tocopherol (p<0.05) in the autoxidation system of linoleic acid. These results suggest that luteolin and 5,6,4'-trihydroxy-7,3'-dimethoxy-flavone may be used as a potential source of anti-inflammatory agents with antioxidative activity.

• Journal of Microbiology and Biotechnology
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• 제19권4호
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• pp.387-390
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• 2009

Microbial UDP-glycosyltransferases can convert many small lipophilic compounds into glycons using uridine-diphosphate-activated sugars. The glycosylation of flavonoids affects solubility, stability, and bioavailability. The gene encoding the UDP-glycosyltransferase from Bacillus cereus, BcGT-3, was cloned by PCR and sequenced. BcGT-3 was expressed in Escherichia coli BL21(DE3) with a glutathione S-transferase tag and purified using a glutathione S-transferase affinity column. BcGT-3 was tested for activity on several substrates including genistein, kaempferol, luteolin, naringenin, and quercetin. Flavonols were the best substrates for BcGT-3. The enzyme dominantly glycosylated the 3-hydroxyl group, but the 7-hydroxyl group was glycosylated when the 3-hydroxyl group was not available. The kaempferol reaction products were identified as kaempferol-3-O-glucoside and kaempferol-3,7-O-diglucoside. Kaempferol was the most effective substrate tested. Based on HPLC, LC/MS, and NMR analyses of the reaction products, we conclude that BcGT-3 can be used for the synthesis of kaempferol 3,7-O-diglucose.

• 농업과학연구
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• 제38권2호
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• pp.213-217
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• 2011

Agrobacterium rhizogenes, a gram-negative soil bacterium, is one of the most widely studied among them. A, rhizogenes can transfer T-DNA, excised from Ri (root inducing)-plasmids from the bacterial to the plant cell. It is the causal agent of 'hairy root' diseases in plants, and has been used for the production of hairy root cultures from a multitude of species. Five different strains of Agrobacterium rhizogenes differed in their ability to induce Scutellaria baicalensis hairy roots and also showed varying effects on the growth in hairy root cultures. A. rhizogenes R 1000 is the most effective strain for the induction (57.3%) and growth (11.9 g $L^{-1}$) in hairy root of Scutellaria baicalensis. Our results demonstrate that use of suitable strains of A. rhizogenes may allow study of the regulation of flavone biosynthesis in hairy root cultures of Scutellaria baicalensis.

• 한국식품영양과학회지
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• 제24권5호
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• pp.702-706
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• 1995

A major component(compound A) in the ethylacetate fraction exhibited a strong antimicrobial activity was identified by UV, IR, FABMS and NMR. The compound A showed strong absorbance at 209, 259 and 359nm, indicating a flavonoid ring structure. IR spectrum possessed absorbance of OH at 3400∼3300cm-1, ketone at around 1650cm-1, and aromatic C=C at around 1660cm-1. Molecular weight of the compound A calculated as 478 from the information of m/z 479(M＋H)+ and m/z 477(M-H)+ in the FABMS spectrum. Molecular formula of this compound was found to be C22H22O12 from m/z 479.1220(＋3.1mmu for C22H23O12) of HRFABMS spectrum and from 13C-NMR spectrum. 1H-NMR and 13C-NMR spectra of the compound A revealed aromatic proton and benzene rings. Distortionless enhancement by polarization transfer(DEPT) exhibited that the compound A possessed 10 quaternary carbons and 3 substituted benzene rings including a methoxy group substitution. The compound A was identified as isorhamnetin 3-O-β-glucopyranoside by spectrophotometric methods in conjunction with 1H-1H COSY, 1H-13C COSY and HMBC, which revealed a flavone with OH group at 3, 5, 7, and 4' and methoxy group at 3' positions esterified to glucose.

• Biomolecules & Therapeutics
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• 제23권2호
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• pp.165-173
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• 2015

Most skin damage caused by ultraviolet B (UVB) radiation is owing to the generation of reactive oxygen species. Phytochemicals can act as antioxidants against UVB-induced oxidative stress. This study investigated the protective effects of the flavone galangin against UVB-induced oxidative damage in human keratinocytes. Galangin efficiently scavenged free radicals and reduced UVB-induced damage to cellular macromolecules, such as DNA, lipids, and proteins. Furthermore, galangin rescued cells undergoing apoptosis induced by UVB radiation via recovering mitochondrial polarization and down-regulating apoptotic proteins. These results showed that galangin protects human keratinocytes against UVB radiation-induced cellular damage and apoptosis via its antioxidant effects.

• Biomolecules & Therapeutics
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• 제24권4호
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• pp.446-452
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• 2016

Pharmacokinetic interaction of chrysin, a flavone present in honey, propolis and herbs, with caffeine was investigated in male Sprague-Dawley rats. Because chrysin inhibited CYP1A-selective ethoxyresorufin O-deethylase and methoxyresorufin O-demethylase activities in enriched rat liver microsomes, the pharmacokinetics of caffeine, a CYP 1A substrate, was studied following an intragastric administration with 100 mg/kg chrysin. In addition to the oral bioavailability of chrysin, its phase 2 metabolites, chrysin sulfate and chrysin glucuronide, were determined in rat plasma. As results, the pharmacokinetic parameters for caffeine and its three metabolites (i.e., paraxanthine, theobromine and theophylline) were not changed following chrysin treatment in vivo, despite of its inhibitory effect on CYP 1A in vitro. The bioavailability of chrysin was found to be almost zero, because chrysin was rapidly metabolized to its sulfate and glucuronide conjugates in rats. Taken together, it was concluded that the little interaction of chrysin with caffeine might be resulted from the rapid metabolism of chrysin to its phase 2 metabolites which would not have inhibitory effects on CYP enzymes responsible for caffeine metabolism.