Institute of Human Nutrition and Food Science, University of Kiel , Hermann-Rodewald-Straße 6, 24118 Kiel, Germany.
Institute of Food Chemistry, Technische Universität Braunschweig , Schleinitzstraße 20, 38106 Braunschweig, Germany.
J Agric Food Chem. 2016 Jul 27;64(29):5901-8. doi: 10.1021/acs.jafc.6b02292. Epub 2016 Jul 14.
Black and purple carrots have attracted interest as colored extracts for coloring food due to their high content of anthocyanins. This study aimed to investigate the polyphenol composition of black carrots. Particularly, the identification and quantification of phenolic compounds of the variety Deep Purple carrot (DPC), which presents a very dark color, was performed by HPLC-PDA and HPLC-ESI-MS(n) analyses. The separation of polyphenols from a DPC XAD-7 extract into an anthocyanin fraction (AF) and co-pigment fraction (CF; primarily phenolic acids) was carried out by membrane chromatography. Furthermore, possible anti-diabetic effects of the DPC XAD-7 extract and its AF and CF were determined. DPC samples (XAD-7, CF, and AF) inhibited α-amylase and α-glucosidase in a dose-dependent manner. Moreover, DPC XAD-7 and chlorogenic acid, but not DPC CF and DPC AF, caused a moderate inhibition of intestinal glucose uptake in Caco-2 cells. However, DPC samples did not affect glucagon-like peptide-1 (GLP-1) secretion and dipeptidyl peptidase IV (DPP-4) activity. Overall, DPC exhibits an inhibitory effect on α-amylase and α-glucosidase activity and on cellular glucose uptake indicating potential anti-diabetic properties.
黑紫色胡萝卜因富含花色苷而成为食品着色的有色提取物，引起了人们的关注。本研究旨在研究黑胡萝卜的多酚组成。特别是，通过 HPLC-PDA 和 HPLC-ESI-MS(n)分析对深紫色胡萝卜（DPC）品种的酚类化合物进行了鉴定和定量。通过膜色谱法将 DPC XAD-7 提取物中的多酚分离成花色苷（AF）和共色素（CF；主要是酚酸）。此外，还测定了 DPC XAD-7 提取物及其 AF 和 CF 的可能抗糖尿病作用。DPC 样品（XAD-7、CF 和 AF）以剂量依赖性方式抑制α-淀粉酶和α-葡萄糖苷酶。此外，DPC XAD-7 和绿原酸，但不是 DPC CF 和 DPC AF，可适度抑制 Caco-2 细胞中的肠内葡萄糖摄取。然而，DPC 样品对胰高血糖素样肽-1（GLP-1）的分泌和二肽基肽酶 IV（DPP-4）活性没有影响。总的来说，DPC 对α-淀粉酶和α-葡萄糖苷酶活性以及细胞内葡萄糖摄取具有抑制作用，表明具有潜在的抗糖尿病特性。
