Bioactivity-guided isolation of antidiabetic principles from the methanolic leaf extract ofBryophyllum pinnatum

Abstract

The antidiabetic principles from methanolic leaf extract of Bryophyllum pinnatum were isolated. The leaf extract was fractionated on silica gel using column chromatography and identified using nuclear magnetic resonance (NMR) spectrometry. The ethylacetate fraction of the partitioned methanolic extract of B. pinnatum lowered blood glucose of alloxan‐induced diabetic rats and inhibited α‐amylase and α‐glucosidase with IC50 137.89 and 110.15 µg/mL, respectively. In addition to lowering blood glucose, fractions A and B inhibited α‐amylase with IC50 57.43 and 43.84 µg/mL and α‐glucosidase with IC50 11.15 and 25.79 µg/mL, respectively. 1H and 13C NMR showed that fractions A and B are quercetin and kaempeferol, respectively. Molecular docking revealed that kaempferol and quercetin interacted with amino acid residues that bind/hydrolyze substrate molecules These compounds reversed altered lipid profile and oxidative stress biomarkers. Our findings showed that kaempferol and quercetin are responsible for the antidiabetic activity of B. pinnatum. Practical application Bryophyllum pinnatum is an edible vegetable plant in some parts of Nigeria, and its consumption could improve diabetic condition and lower postprandial glucose. Furthermore, extract of the leaves could be developed into food supplements for managing diabetes and its associated complications including dyslipidaemia and oxidative stress.

Antidiabetic activity‐guided isolation of gallic and protocatechuic acids fromHibiscus sabdariffacalyxes

“…The isolated gallic and protocatechuic acids significantly lowered the TC, TAG, and LDLc with a parallel increase of HDLc in the serum of diabetic rats (Figure ). This activity, which is consistent with the findings of Harini and Pugalendi () and Punithavathi et al (), suggests that gallic acid and protocatechuic acid, in addition to reducing blood glucose, could prevent cardiovascular diseases including atherosclerosis and coronary artery disease (Adigun, Oladiji, & Ajiboye, ; Ajiboye, Akinpelu, et al, ; Ibitoye & Ajiboye, ; Ibitoye, Olofinsan, et al, ).…”

“…Consumption of plant‐based foods is on the increase (Ibitoye, Aliyu, & Ajiboye, ) because of awareness of their health benefits and bioactive constituents such as polyphenols and micro‐ and macronutrients (Ibitoye, Olofinsan, et al, ; Oloyede et al, ). In this study, we present gallic and protocatechuic acids as the α‐amylase and α‐glucosidase inhibitory principles in H. sabdariffa calyx.…”

“…Male albino Wistar rats (148.32 ± 4.06 g) obtained from the Animal House of Department of Biochemistry, University of Ilorin, Ilorin, Nigeria were used in this study after the ethical approval (NUN/BCH/ECULA/018/006). Diabetes was induced with 150 mg/kg body weight (BW) alloxan monohydrate and confirmed by estimating the glucose in the blood of animals as previously described (Ibitoye, Olofinsan, et al, ).…”

“…α-Amylase and α-glucosidase inhibitory activities of the aqueous extract of H. sabdariffa and its solvent, solvent-partitioned extract, or column chromatographic fractions were determined according to the procedure outlined by Ibitoye, Olofinsan, et al (2018).…”

“…WHO () projected that death resulting from diabetes is anticipated to double by the year 2030. Indeed, these devastating consequences of untreated diabetes result from secondary complications—e.g., inflammation, retinopathy, neuropathy, nephropathy, predisposition to cardiovascular diseases, and ulcerations (Barrett, ; Halim & Halim, ; Ibitoye, Olofinsan, Teralı, Ghali, & Ajiboye, ; Tesfaye, ; Thomas & Karalliedde, ; Zaman, Aleem, & Ahmed, ). Interestingly, these complications are positively correlated with postprandial hyperglycemia (Jaiswal et al, ).…”