Inhibition of digestive enzymes by medicinal plant aqueous extracts used to aid the treatment of obesity

Abstract

The objective of this work was to perform digestive enzyme inhibition assays with aqueous extracts of the medicinal plants: Aloe vera (L.) Burm. (aloe), Simaba ferruginea St. Hil. (calunga), Baccharis trimera (Less.) DC (carqueja), Garcinia cambogia Desr., Tournefortia paniculata Cham. (marmelinho) and with the aqueous extract of the combination of those plants in the proportions 1:1, 5:0, 5:1, 5:0, 5, used as aids in the treatment of obesity. The α-amylase, α-glycosidase, lipase and trypsin enzyme inhibition analyses were conducted in the presence and absence of a simulated gastric fluid. In the absence of the simulated gastric fluid, the enzymes underwent variable inhibition by the plant extracts, except for lipase, that did not undergo any inhibition. In the presence of the simulated gastric fluid, only the α-amylase and α-glycosidase enzymes were inhibited by the plant extracts. The combination of the plants did not cause inhibition in any of the evaluated digestive enzymes. Those results reveal that the aqueous plant extracts aloe, carqueja and marmelinho present potential as adjuvant in the treatment of obesity and of other dyslipidemias, because they inhibit α-amylase (marmelinho) and α-glycosidase (aloe, carqueja and marmelinho) after the gastric digestion simulation; the same cannot be said of the plants in combination. Key words: α-amylase, α-glycosidase, lipase, trypsin, medicinal plants, obesity.