The aim of study to investigate the phytochemicals and biological activities the bark of Betula schmidtii. The studies consisted of the solvent extraction, followed by the isolation of phenolic components 1~3 from ethyl acetate-soluble fraction of Betula schmidtii Bark. Their chemical structures were identified as arbutin (1), ρ-coumaric acid (2) and ferulic acid (3) using Ultraviolet-Visible (UV-Vis) Spectrophotometer, Electrospray Ionization Mass Spectrometry (ESI-MS) (negative ion mode), 1H-Nuclear Magnetic Resonance (NMR), 13C-NMR, 1H-1H Correlation Spectroscopy (COSY) and 1H-13C Hetero Nuclear Multiple Quantum Correlation (HMQC) spectral data. Compounds 1~3 shows the anti-oxidant effect with IC50 values of 29.74±1.52, 21.32±1.07 and 34.41±1.24 in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, respectively. Also, compounds 1~3 exhibited mushroom tyrosinase inhibitory activity with IC50 values of 31.14±1.07, 42.54±1.46 and 69.22±1.43 μM, respectively.

The lyophilization of the solution extracted from 60 percent of acetone applied to persimmon leaves, the compounding process in accordance with the solution's concentration, and the gel filteration through Sephadex G-50 of biologically activated substances obstructing enzyme activity, such as tyrosinase, xanthine oxidase, and angiotesin converting enzyme (ACE) led to the assumption that polyphenol was the compound serving as biologically activated substances obstructing enzyme activity. Xanthine oxidase involved in pruine metabolism oxidizes hypoxanthine to xanthine and xanthine to uric acid. In the continuous study for natural compound, nine flavan-3-ols have been isolated from the persimmon leaves. The structures of (+)-catechin, (+)-gallocatechin, procyanidin B-1, pyrocyanidin C-1, prodelphinidin B-3, gallocatechin-(4α→8)-catechin, procyanidin B-7-3-O-gallate, procyanidin C-1-3'-3'-3'-O-trigallate and (-)-epigallocatechin-(4α→8)-epigallocatechin-(4α→8)-catechin were established by NMR and their inhibitory effect on xanthine oxidase activity was investigated. Procyanidin B-7-3-O-gallate, (-)-epigallocatechin-(4α→8)-epigallocatechin-(4α→8)-catechin and procyanidin C-1-3'-3'-3'-O-trigallate showed 94%, 90.69%, 80.90% inhibition at 100 (μ)M and inhibited on the angiotensin converting enzyme respectively. Procyanidin B-7-3-O-gallate and procyanidin C-1-3'-3'-3'-O-trigallate showed 66%, 63% inhibition at 100 (μ)M and inhibited on the xanthine oxidase competitively. Procyanidin C-1-3'-3'-3'-O-trigallate showed 70% inhibition at 100 (μ)M and inhibited on the tyrosinase competitively.

본 연구에서는 섬오갈피 줄기 추출물 및 용매 분획물의 미백 활성을 검색하고 유효성분을 분리하여 화학구조를 규명하였다. 섬오갈피 줄기 에탄올 추출물 및 용매 분획물의 멜라닌 생성 억제활성을 측정한 결과, 헥산 및 에틸아세테이트 분획물에서 우수한 멜라닌 생성 억제 효과가 있음을 확인하였다. 비교적 세포독성이 적은 헥산 분획물에서 유효성분을 찾고자 크로마토크래피를 실시하여 3개의 화합물을 분리하였으며 1H 및 13C NMR 데이터 분석 및 문헌 비교를 통하여 화학구조를 동정하였다; kaurenoic acid (1), 16α-hydro-17- isovaleroyloxy-ent-kauran-19-oic acid (2), 16α-hydroxy-17-isovaleroyloxy-ent-kauran-19-oic acid (3). 분리된 화합물에 대한 미백 활성 실험 결과, 화합물 1-3 모두 농도의존적으로 멜라닌 생성을 억제하 였다. 또한 세포 내 티로시나제 효소의 활성을 감소시킴을 확인하였으며 이러한 연구 결과를 바탕으로 섬오갈피 줄기 추출물은 기능성 미백 화장품 소재로써 활용 가능할 것이라 사료된다.

Compounds of isolated from roots extract of Pueraria thunbergiana were tested their inhibitory effects on α-glucosidase and α-amylase. Inhibitory activity of methylene chloride (MC) fraction and ethyl acetate (EA) fraction against α-glucosidase showed more than 60% at a concentration of 500μg/ml. Among the nine compounds tested on α-glucosidase, biochanin A, (-)-tuberosin and calycosin from MC fraction and daidzein from EA fraction were stronger inhibitors than acarbose (IC50=530μg/ml), and their IC50 were 9, 144, 328 and 20μg/ml, respectively. Biochanin A and (-)-tuberosin also inhibited α-amylase activity as like as acarbose IC50=20.5μg/ml), and their IC50 were 22 and 348μg/ml, respectively. Although daidzein was already known α-glucosidase inhibitory effects, it was newly evaluated that biochanin A and (-)-tuberosin inhibited α-glucosidase as well as α-amylase, and that calycosin did α-glucosidase.