Commercial ${\gamma}$-Oryzanol Inhibits the Formation of C-7 Oxidized Cholesterol Derivatives (OCDs) in an Aqueous Model System during Cholesterol Autoxidation

수용성 모델시스템 내에서의 상업적 ${\gamma}$-Oryzanol의 C-7 산화 콜레스테롤 유도체 생성 저해효과

  • Published : 2008.03.31

Abstract

The inhibition of cholesterol autoxidation by commercial ${\gamma}$-Oryzanol (0, 50, 100, and 300 ppm) was studied in an aqueous model system for 20 h at pH 5.5 and $80^{\circ}C$. The inhibition effectiveness of the commercial ${\gamma}$-Oryzanol was followed by the retention of cholesterol and the formation of C-7 oxidized cholesterol derivatives (OCDs). Changes in the amount of ${\gamma}$-Oryzanol in the aqueous system were determined during cholesterol autoxidation. A method to detect the levels of 7-ketocholesterol, $7{\alpha}$-hydroxycholesterol and $7{\beta}$-hydroxycholesterol in an aqueous model system with ${\gamma}$-Oryzanol was developed by using the hexane-ethyl acetate extraction system and high-performance liquid chromatography. Results showed that the levels of C-7 OCDs in an aqueous dispersion containing 300 ppm of ${\gamma}$-Oryzanol were not significantly (p>0.05) increased, when compared to other treatments (0, 50, and 100 ppm), during the accelerated cholesterol oxidation.

미강 추출 상업용 유통 감마오리자놀의 콜레스테롤 자동산화에 의한 C-7 산화 콜레스테롤 유도체 생성 저해 효과가 수용성 모델 시스템을 이용하여 검토되었다. C-7 콜레스테롤 산화 유도체 (C-7 oxidized cholesterol derivatives: C-7 OCDs) 생성을 위해 콜레스테롤과 감마오리자놀이 분산된 수용성 모델시스템은 구리이온을 촉매로 pH 5.5와 $80^{\circ}C$의 가혹 조건에서 20시간 동안 반응되었다. 산화 유도 기간에 따른 C-7콜레스테롤 산화 유도체 (7-ketocholesterol, 7{\alpha}$-hydroxy-cholesterol과 7b-hydroxycholesterol)의 생성 정도와 감마오리자놀 및 콜레스테롤 변화 추이 정도가 핵산과 에틸아세테이트를 이용한 용매 추출법과 고속 액체크로마토그래프 (high-performance liquid chromatography) 테크닉을 이용 정량적으로 분석되었다. 분석 결과 콜레스테롤 산화 유도 기간에 따른 7-ketocholesterol 생성비율은 7-hydroxycholesterol 이성체 (${\alpha}$-형:${\beta}$-형) 대비 약 2:1의 비율로 생성되었으며, 7-hyoxycholesterol 이성체에 있어서는 ${\alpha}$-형 대비 ${\beta}$-형의 생성 정도가 약 1:2의 비율로 나타났고, 총 C-7 산화콜레스테롤의 생성은 상대적인 고농도(300 ppm) 감마오리자놀 처리 모델 시스템에서 효과적으로 저해되었다.

Keywords

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