Bioassay-guided Antidiabetic Study of Chromatographic Fractions of Boswellia Dalzielii Hutch. Leaf Extract

Background: Boswellia dalzielli Hutch. (Burseraceae) is a medicinal plant, which is used locally by the local dwellers for the management and treatment of microbial-related diseases, neurological conditions, stomach spasms, diabetes, etc.  Objectives: This study aimed at isolating a phytochemical of anti-diabetic potentials from the leaf of Boswellia dalzielii in alloxan-induced diabetic rats.  Methods: The n-butanol fraction of the leaf of B. dalzielii was fractionated using column chromatography. Fractions obtained were screened phytochemically and by antidiabetic study.  Results: Encoded column fraction B۴ (۱۵۰ mg/kg) produced a maximum reduction (۷۲.۴۵%) in fasting blood glucose (FBG) of animals after ۷ hours, which was significantly (P<۰.۰۵) different from the controls (alloxan-induced diabetic rats) and was better than glibenclamide (۵۲.۶۷%). The re-column fractions obtained from fraction B۴ were pooled based on similar Rf values and encoded B۴۱-B۴۸, and subjected to further antidiabetic evaluation on alloxan-induced mice. Eight sub-fraction with doses of ۵۰ mg/kg each were administered to all the groups. Fraction B۴۴ had the highest reduction of FBG by ۶۵.۶۳%, whose effect was significantly higher than the non-treated diabetic mice (negative control) and glibenclamide (۵۲.۶۸%) at ۲.۰ mg. Further purification of sub-fraction B۴۴ with Sephadex LH-۲۰ yielded encoded fractions A, B, and C. Isolate C showed the highest inhibition of glycemia (۲۲.۸۵%) when the dose of ۱۰ mg/kg was administered (p.o).  Conclusion: The antidiabetic effect of the plant in laboratory animals (rats and mice) may be due to the presence of the isolated phenolic compounds.

Keywords:

Boswellia dalzielii , Phytochemicals , Glibenclamide , Alloxan , Hyperglycaemia