The purpose of this study was to determine the optimum extraction method suitable for the availability of biological activities in unripe apples known to be rich in functional components. Unripe apples ‘Hongro’ picked on May 28th, 2019 were extracted by various extraction methods (hot water, ethanol, enzymatic pre-treatment, ultrasonic wave, and subcritical water) and their extracts were investigated yield, effective component contents, and antioxidant activities. Overall, the yields by the extraction solvent were higher in water than in organic solvent(ethanol) because water-soluble compounds were eluted from a polar solvent. Total phenol contents of the ultrasonic wave (ethanol) extracts were significantly higher in 6 times than hot water extract. Contents of flavonoid were highest in the ethanol extract at 29.14 mg QE/g. Contents of tannin and ursolic acid were also significantly higher in the ultrasonic wave (ethanol) extract. The DPPH radical and ABTS radical scavenging activities were the strongest in the ultrasonic wave (ethanol) extract. Correlation between effective components and antioxidant activities was high in the total phenol content with ABTS and the ursolic acid content with DPPH (p<0.01). The above results suggested that ultrasonic wave (ethanol) extract of unripe apples has the potential to act as a functional material.

Abstract
서 론
재료 및 방법
    1. 실험재료
    2. 추출물의 제조 및 수율 측정
    3. 총 phenol 및 총 flavonoid 함량
    4. 총 tannin 함량
    5. Ursolic acid 함량
    6. 항산화활성
    7. 통계처리
결과 및 고찰
    1. 수율
    2. 총 phenol 및 총 flavonoid 함량
    3. 총 tannin 및 ursolic acid 함량
    4. 항산화활성 및 상관관계
요약 및 결론
References

• 홍정진(경상남도농업기술원 사과이용연구소) | Jeong Jin Hong (Apple Utilization Research Institute, Gyeongsangnam-do Agricultural Research & Extension Services) Corresponding author
• 설희경(경상남도농업기술원 사과이용연구소) | Hui Gyeong Seol (Apple Utilization Research Institute, Gyeongsangnam-do Agricultural Research & Extension Services)
• 오주열(경상남도농업기술원 사과이용연구소) | Ju Youl Oh (Apple Utilization Research Institute, Gyeongsangnam-do Agricultural Research & Extension Services)
• 정은호(경상남도농업기술원 사과이용연구소) | Eun Ho Jeong (Apple Utilization Research Institute, Gyeongsangnam-do Agricultural Research & Extension Services)
• 장영호(경상남도농업기술원 연구개발국) | Young Ho Chang (Dept. of Research & Development, Gyengnam Agriculture Research and Extension Services)