Sun Shengwei, Huang Siqi, Shi Yaning, Shao Yuting, Qiu Jiarong, Sedjoah Rita-Cindy Aye-Ayire, Yan Zhenzhen, Ding Liping, Zou Dandan, Xin Zhihong
Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
Key Laboratory of Food Processing and Quality Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
Food Chem. 2021 Jul 30;351:129232. doi: 10.1016/j.foodchem.2021.129232. Epub 2021 Feb 9.
Non-extractable polyphenols (NEPPs) in pomegranate peel were released by acid hydrolysis followed by extraction using ethyl acetate (EtOAc). Ten NEPPs were identified in the hydrolysate using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Six compounds were then isolated from the EtOAc extracts whose structures were identified as β-sitosterol-3-O-glycoside (1), β-sitosterol (2), ursolic acid (3), corosolic acid (4), asiatic acid (5) and arjunolic acid (6) using a wide range of spectroscopic analyses. Compounds 4-6 were isolated for the first time from pomegranate peel. Antimicrobial experiments revealed that compound 3 and 5 showed significant antimicrobial activity against a range of pathogens, particularly compound 5 which exhibited selective inhibitive activity towards Staphylococcus aureus with a minimum inhibitory concentration (MIC) of 16 μg/ml. The present study has provided new insights into the composition of bound chemicals in pomegranate peel and laid a foundation for improving its further processing and utilization.
石榴皮中的非可提取多酚（NEPPs）通过酸水解释放，然后用乙酸乙酯（EtOAc）萃取。使用基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF MS）在水解产物中鉴定出10种NEPPs。然后从EtOAc提取物中分离出6种化合物，通过广泛的光谱分析确定其结构为β-谷甾醇-3-O-糖苷（1）、β-谷甾醇（2）、熊果酸（3）、科罗索酸（4）、积雪草苷（5）和阿江榄仁酸（6）。化合物4-6首次从石榴皮中分离得到。抗菌实验表明，化合物3和5对多种病原体具有显著的抗菌活性，特别是化合物5对金黄色葡萄球菌表现出选择性抑制活性，最低抑菌浓度（MIC）为16μg/ml。本研究为石榴皮中结合化学成分的组成提供了新的见解，为改善其进一步加工和利用奠定了基础。
