Inhibitory Effects of Aqueous and Hydroalcoholic Extracts from Jatobá Coat (Hymenaea courbaril L.) on Pancreatic Amylase and Starch Absorption

TL;DR

Jatobá coat extracts can inhibit pancreatic amylase and reduce starch-induced hyperglycemia in mice.

Contribution

The study identifies jatobá coat extracts as potential agents for glycemic control through α-amylase inhibition.

Findings

Aqueous and hydroalcoholic extracts from jatobá coat inhibited α-amylase with IC50 values of 81.98 µg/mL and 51.06 µg/mL.

Both extracts reduced starch-induced hyperglycemia in mice, with the aqueous extract showing broader dose efficacy.

In silico analysis suggests procyanidin dimers and flavonoids may contribute to the inhibitory effects.

Abstract

Jatobá (Hymenaea courbaril) is a native tree abundant in Brazil. The fruit coat is an industrial by-product of jatobá flour processing, typically discarded. Presently, within the circular bioeconomy concept, there are efforts underway that aim at finding economically viable applications for the bio-residues of jatobá. Within this context, the present work attempts to find possible applications for the jatobá coat in glycemic control through inhibition of α-amylase activity. Aqueous and hydroethanolic extracts were used. In vitro experiments included detailed kinetic studies with an α-amylase catalyzed reaction. Starch absorption in vivo was assessed by means of a starch tolerance test in mice. Both extracts inhibited α-amylase. The IC50 values for the aqueous and hydroalcoholic extracts were 81.98 ± 3.53 µg/mL and 51.06 ± 0.42 µg/mL, respectively. The inhibition was of the non-competitive type. Both extracts reduced hyperglycemia caused by starch administration in mice, the aqueous extract being effective over a larger dose range. This action can be attributed to the α-amylase inhibition. In silico studies suggested that procyanidin dimers, taxifolin 7-O-rhamnoside, and quercetin 7-rhamnoside contribute, but several other not-yet-identified substances may be involved. The findings suggest that aqueous and hydroalcoholic extracts from jatobá coat warrant further investigations as potential modulators of glycemia following starch ingestion.

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