To confirm the industrial applicability of crabapple (Malus prunifolia; MP), which shows greater potential than conventional apples (Malus domestica; MD) as a raw material for developing immunostimulants, we compared the macrophage-activating effects of hot-water extracts (MP-HW and MD-HW) and fractionated the active components to identify their characteristics. MP-HW significantly enhanced the secretion of macrophage-activating factors such as NO, TNF-α, MCP-1, IL-6, and IL-12, stimulating macrophages more effectively than MD-HW. Subsequently, when MP-HW was fractionated into a low-molecular-weight fraction (MP-L) and crude polysaccharides (MP-CP) through ethanol precipitation, MP-CP exhibited significantly higher activity than the other fractions. Furthermore, MP-CP, the macrophage-activating crude polysaccharides, was further fractionated into four sub-fractions (MP-CP-0, -I, -II, and -III) using DEAE-Sepharose CL-6B (Cl－ form), with MP-CP-III identified as the active fraction responsible for macrophage stimulation. In HPLC molecular analysis, the active fraction MP-CP-III displayed a nearly purified single peak around 115 kDa, and its main component sugars were identified as galacturonic acid, rhamnose, galactose, and arabinose, suggesting that they are pectic-like polysaccharides. In conclusion, polysaccharides derived from crabapple promote macrophage activation, confirming their industrial applicability as immunostimulants.

Abstract
서 론
재료 및 방법
    1. 꽃사과 열수추출물의 조제
    2. RAW 264.7 세포주의 대식세포 자극 활성
    3. 주정침전 및 이온교환 크로마토그래피에 의한 활성 다당 분획
    4. 분자량 분포
    5. 구성분 및 구성당 분포
    6. 통계처리
결과 및 고찰
    1. 꽃사과 및 사과의 대식세포 자극 활성 비교평가
    2. 꽃사과열수추출물로부터분획한획분의대식세포활성
    3. 조다당획분의 이온교환 크로마토그래피를 통한 분획
    4. 조다당획분의 이온교환 크로마토그래피로 분획된 획분의 대식세포 활성
    5. 이온교환 크로마토그래피에 의해 분리된 획분의 화학적 특성
요약 및 결론
감사의 글
References

• 김연숙(경기도경제과학진흥원 바이오센터 바이오연구개발팀 연구원) | Yeon Suk Kim (Researcher, Bio R&D Team, Bio Center, Gyeonggido Business & Science Accelerator, Suwon 16229, Korea)
• 신현영(국립한국교통대학교 바이오산업연구소 박사후연구원) | Hyun Young Shin (Postdoctoral Researcher, Institute of Biotechnology and Bioindustry, Korea National University of Transportation, Chungbuk 27909, Korea)
• 신광순(경기대학교 식품생물공학과 교수) | Kwang-Soon Shin (Professor, Dept. of Food Science and Biotechnology, Kyonggi University, Suwon 16227, Korea)
• 유광원(국립한국교통대학교 식품영양학전공 교수) | Kwang-Won Yu (Professor, Major in Food and Nutrition, Korea National University of Transportation, Chungbuk 27909, Korea) Corresponding author