청국장추출물과 청국장의 주요한 플라보노이드의 하나인 genistein의 HepG2 세포에서 Trp-P-1 유도 세포독성과 DNA손상에 대한 보호효과를 평가하였다. 청국장추출물과 주요 플라보노이드성분 genistein은 Trp-P-1 유도 세포독성에 대하여 세포독성보호효과를 나타내었다. 청국장추출물 은 Trp-P-1 유도 DNA single strand breaks를 억제하였다. 한편, 청국장추출물은 HepG2 세포에서 Trp-P-1 유도에 의한 CYP1A1와 CYP1A2 발현의 억제를 나타내었다. 청국 장추출물과 genistein은 Trp-P-1에 의한 유도 세포독성과 DNA손상에 대하여 CYP1A1, CYP1A2 발현억제에 의하 여 보호효과가 나타나는 것으로 판단된다. 한국의 전통 콩 발효식품인 청국장은 게놈 불안정성(genomic instability)을 일으키는 heterocyclic amines (HCAs)과 같은 식품의 가열 조리로부터 올 수 있는 발암물질에 대한 유전독성을 예방할 수 있는 유망한 기능성물질로서 활용가능성이 있을 것으로 판단된다.

본 연구의 목적은 NIH3T3와 HepG2 세포에서 에탄올유도 세포독성 및 유전독성에 대하여 녹차엑기스(GTE)와 epigallocatechin-3-gallate (EGCG)의 보호작용을 평가하는데 있다. 세포생존율은 MTT assay를 실시하였으며 DNA 손상도는 Comet assay로 실시한 결과 에탄올은 농도의존적인 세포독성과 유전독성을 나타내었다. 한편 GTE와 EGCG는 에탄올 유도 세포독성 및 DNA 손상에 대하여 유의성 있는 억제효과를 나타내었으며 DPPH시험과 LDL oxidation 및 8OH-2``dG 생성시험에서 항산화효과를 나타내었다. 한편 녹차성분 함유 시판 리큐르주도 순수 에탄올에 비하여 세포독성억제 및 DNA 손상억제효과를 나타내었다. 이상의 시험결과 GTE와 함유 EGCG는 항산화성 유전독성억제기전을 통한 에탄올독성저감 물질로 판단된다.

The antioxidative, radical scavenging and cyto-protective effects of Cassia torn L. seeds and it major component, nor-rubrofusarin-6-β-D-glucoside (nor-rubrofusarin), were studied to evaluate their inhibitory activity against hydrogen peroxide-induced oxidative stress. 70% ethanol extract of Cassia tora L. seeds and nor-rubrofusarin also were tested for the evaluation of anticlastogenicity against mitomycin C-induced micronucleated reticulocytes in mouse peripheral blood. The extract of Cassia tora seeds and nor-rubrofusarin showed an antioxidative effect on the lipid peroxidation of ethyl linoleate with Fenton's reagent and free radical scavenging effect to DPPH radical generation, respectively. They showed a protective effect against H₂O₂-induced cytotoxicity in CHL cells. The extract of Cassia tora L. seeds and nor-rubrofusarin showed a strong anticlastogenicity against mitomycin C-induced micronuclei formation. Results from our study indicate that the extract of Cassia tora L. seeds and nor-rubrofusarin are capable of protecting the lipid peroxidation, free radical generation and cytotoxicity induced by reactive oxygen species. They also have an anticlastogenicity toward DNA crosslinking agent like mitomycin C.

Panax ginseng C.A. Meyer has been extensively used in the traditional oriental medicine as a restorative, tonic and prophylatic agent. Petroleum ether extract of panax ginseng C.A. Meyer (GPE) and its several fractions (P1-P5) were tested for the evaluation of antigenotoxicity against N-methyl-N-nitrosourea (MNU) and benzo(a)pyrene [B(a)P]-induced micronucleated reticulocytes in mouse peripheral blood. GPE and P2 showed more significant anticlastogenicity than other fractions did. To elucidate the anticlastogenic action mechanism of GPE and P2 against B(a)P, the alteration of B(a)P metabolism was studied. GPE and P2 inhibited B(a)P metabolism in the presence of S-9 mix and decreased B(a)P-DNA binding in calf thymus DNA with S-9 mix. They also decreased [3H] MNU induced DNA binding and methylation to 7-methyl guanine and O^5-methyl guanine adducts in calf thymus DNA by HPLC analysis. These results suggest that the anticlastogenicity of GPE and P2 on the B(a)P or MNU-induced clastogenicity is due to decrease of DNA binding with B(a)P or MNU, the inhibition of metabolism with B(a)P and the inhibition of methylation in DNA. Therefore, GPE and P2 may be useful chemopreventive agents of alkylating agent like MNU and secondary carcinogen like B(a)P.

Panax ginseng C.A. Meyer has been extensively used in the traditional oriental medicine as a restorative, tonic and prophylatac agent. This study was devised to develop a chemopreventive agent from panax ginseng to be able to suppress the genotoxicity and oxidative damage by reactive oxygen species, which are involved with cancer or aging. Ginseng petroleum ether extract (GPE) and one of its fraction, P2, showed an antioxidative effect on the lipid peroxidation of ethyl linoleate with Fenton's reagents and free radical scavenging effect to 1,1-diphenyl-2-picryl hydrazil (DPPH) radical generation. They also showed the suppressive effect of H₂O₂ or KO₂ induced DNA damage by single cell gel electrophoresis (SCGE). Results from our study indicate that GPE and P2 are capable of protecting lipid peroxidation, and oxidative DNA damage. Therefore, GPE and P2 may be useful chemopreventive agents which are involved with cancer and aging.

In order to compare the suppressive effect of quercetin and several its glycosides, such as quercitrin (quercetin-3-rhamnoside), isoquercitrin (quercetin-3-gluooside), hyperin (quercetin-3-galactoside) and rutin (quercetin-3-rhamnosyl glucoside), on the genotoxicity by Nmethyl-N-nitrosourea(MNU), in vitro sister chromatid exchange(SCE) test using mouse spleen lymphocytes and in viuo micronucleus test using mouse peripheral blood were performed. MNU-indured SCEs in vitro were not decreased by the simultaneous treatment of teat compounds. Among them, quercetin and hyperin showed significant suppressive effects at high dose(10^(-5)M). On the other hand, MNU-induced micronucleated reticulocytes(MNRETs) in vivo were aignificantly decreased with good dose-dependent manner in all compounds tested. However, there were not significant differences between quercetin aglycone and its glycosides in the suppressive effects under experimental condition of this study. These results suggest that both of queroetin aglycone and its glycosides may act as an antigenotoxic agent in vivo and may be useful as a chemopreventive agent of alkylating agent.