Osmanthus fragrans seeds (OFSs) abundant in protein are valuable resources of bioactive peptides. To elucidate the potential hypoglycemic peptides released during the digestion, OFSs protein was extracted and digested in vitro. The effects of the digestion step and molecular weight on the α-glucosidase inhibitory ability of the digested protein were evaluated, and the mechanism and structure of the main effective peptides in the digesta were studied. The results indicated that the digesta after the small intestine digestion displayed higher inhibition (58.5 %), from which the fraction below 3 kDa was more effective (67.34 %). Among the seven sub-fractions (F1∼F7) below 3 kDa, F1 obtained the highest α-glucosidase inhibitory ability (60.69 %). Three peptides (ERFQ, VHHK, and EKFMKE) were identified from F1, and their efficacy was verified by corresponding synthetic peptides, showing the α-glucosidase inhibitory rates of 79.1 % ± 2.24 %, 65.67 % ± 1.97 % and 61.94 % ± 1.97 %, respectively. According to the molecular docking, these peptides inhibited the α-glucosidase by forming secondary forces (e.g. hydrophobic interaction) with the key amino acids (e.g. D327, D443, Y299, and F575) of the enzyme, with docking scores ranging from −151.038 to −171.907. This study demonstrated OFSs could release α-glucosidase inhibitory peptides during digestion and may serve as functional ingredients to control diabetes.

桂花籽（OFSs）富含蛋白质，是生物活性肽的宝贵资源。为了阐明消化过程中释放的潜在降血糖肽，OFSs 蛋白被提取并在体外消化。评价消化步骤和分子量对消化蛋白α-葡萄糖苷酶抑制能力的影响，并研究消化物中主要有效肽的作用机制和结构。结果表明，小肠消化后的食糜表现出较高的抑制作用（58.5%），其中3 kDa以下的部分更有效（67.34%）。在3 kDa以下的7个亚组分（F1∼F7）中，F1获得了最高的α-葡萄糖苷酶抑制能力（60.69%）。从F1中鉴定出三种肽（ERFQ、VHHK和EKFMKE），并通过相应的合成肽验证其功效，显示α-葡萄糖苷酶抑制率分别为79.1%±2.24%、65.67%±1.97%和61.94%±1.97% ， 分别。根据分子对接，这些肽通过与酶的关键氨基酸（例如D327、D443、Y299和F575）形成二次力（例如疏水相互作用）来抑制α-葡萄糖苷酶，对接分数范围为-151.038至−171.907。这项研究证明 OFS 可以在消化过程中释放 α-葡萄糖苷酶抑制肽，并可能作为控制糖尿病的功能成分。