Quercus fabri Hance, a promising Wild Edible Plant Seeds for Functional Foods

Yi Lin, Yuyun Lu, Zhixuan Song, Dejian Huang^*

The seeds of Quercus fabri Hance tree, or the Mandarin duck fruit, have been consumed by Southern Chinese in the form of noodle, yet there is little scientific study on the seeds. We found that, the flesh of the seeds have much lower digestibility compared with that of rice and potato flours. Solvent extraction and assay-guided fractionation of the seed extracts revealed that there are significant inhibitors for starch hydrolase, particularly alpha-amylase. LC-MS(n) data confirmed that the active compounds consist of mainly ellagitannins being the dominant species. In addition, we have characterized the pancreatic lipase inhibitors of the seeds in lipophilic fraction of the extracts. Our results indicate that Quercus fabri Hance seeds are promising for preparation of low glycemic index foods as well as foods for anti-obesity.