Identification and action of phenolic compounds of Jatobá-do-cerrado (Hymenaea stignocarpa Mart.) on α-amylase and α-glucosidase activities and flour effect on glycemic response and nutritional quality of breads

Abstract

This study investigated the phenolic profile of jatobá-do-cerrado (Hymenaea stignocarpa Mart.) extracts submitted to in vitro digestion, the inhibition of α-amylase and α-glucosidase activities; and the effect of jatobá-do-cerrado flour addition on the nutritional quality, glycemic index (GI) and acceptability of breads. The phenolic composition was determined by UPLC-MS. Bread formulations were developed adding the jatobá-do-cerrado flour at 10, 20 and 30% (w/w) to replace wheat flour. Phenolic compounds of biological relevance such as caffeic acid, kaempferol, quercetin-3-rutinoside and quercetin-3-rhamnoside were present in jatobá-do-cerrado. The phenolic extracts after in vitro digestion significantly inhibited the α-amylase and α-glucosidase activities. Breads with 20% jatobá-do-cerrado flour addition promoted significant reduction (22%) in GI from 70 (control) to 54.3, while 30% addition presented GI of 57.4 and 10% addition a GI of 62.5. The replacement of refined wheat flour by jatobá-do-cerrado flour reduced glycemic response of breads in a non-dose dependent manner. The dietary fibers and the phenolic compounds of jatobá-do-cerrado exerted a synergetic modulation of glucose metabolism by inhibiting sugar metabolic enzymes and glucose absorption. Thus, jatobá-do-cerrado can be included in the diet of healthy individuals and chronic diseases patients, such as diabetics, as an alternative to improve glycemic control.

Keywords: Glycemic response; In vitro digestion; Jatobá-do-cerrado; Mass spectrometry; Phenolic compounds; α-Amylase; α-Glucosidase.