Mashiane Petunia, Manhivi Vimbainashe E, Shoko Tinotenda, Slabbert Retha M, Sultanbawa Yasmina, Sivakumar Dharini
Department of Horticulture, Tshwane University of Technology, Pretoria 0001, South Africa.
Phytochemical Food Network Research Group, Department of Crop Sciences, Tshwane University of Technology, Pretoria 0001, South Africa.
Foods. 2021 Nov 22;10(11):2890. doi: 10.3390/foods10112890.
The leaves of African pumpkins ( L.) are a commonly consumed traditional vegetable. They are a good source of polyphenolic antioxidants and carotenoids, which are, however, affected by cooking or digestion. We investigated the effect of household cooking methods (stir-frying or boiling) on the changes in bioactive metabolites, antioxidant capacity, release and accessibility of β-carotene and also inhibition of inhibitory activity against α-amylase and α-glucosidase enzymes during in vitro digestion of African pumpkin leaves compared to the raw leaves. Compared to boiled or raw leaves, stir-frying improved the availability of bioactive metabolites at the gastrointestinal phase. Quercetin 3-galactoside and rhamnetin 3-O-glucoside (marker compounds) discriminated the stir-fried leaves from raw leaves and boiled leaves after digestion. Stir-frying improved the release and accessibility of β-carotene and enhanced the antioxidant activities compared to boiling. Dialysable fractions of stir-fried leaves exhibited the greatest inhibitory activity against α-amylase and α-glucosidase enzymes compared to the raw and boiled leaves, as well as acarbose. Stir-frying, therefore, is recommended for use in household cooking to benefit consumers by increasing the intake of phenolics and β-carotene.
非洲南瓜（L.）的叶子是一种常见的传统食用蔬菜。它们是多酚类抗氧化剂和类胡萝卜素的良好来源，不过这些成分会受到烹饪或消化的影响。我们研究了家庭烹饪方法（炒或煮）对非洲南瓜叶体外消化过程中生物活性代谢物变化、抗氧化能力、β-胡萝卜素的释放与可及性以及对α-淀粉酶和α-葡萄糖苷酶抑制活性的影响，并与生叶进行了比较。与煮过的叶子或生叶相比，炒制提高了胃肠道阶段生物活性代谢物的可利用性。槲皮素3-半乳糖苷和鼠李素3-O-葡萄糖苷（标记化合物）在消化后能够区分炒制的叶子与生叶和煮过的叶子。与煮制相比，炒制提高了β-胡萝卜素的释放与可及性，并增强了抗氧化活性。与生叶、煮过的叶子以及阿卡波糖相比，炒制叶子的可透析部分对α-淀粉酶和α-葡萄糖苷酶表现出最大的抑制活性。因此，建议在家庭烹饪中采用炒制方法，通过增加酚类物质和β-胡萝卜素的摄入量，使消费者受益。
