Antidiabetic principles of Loranthus micranthus Linn. parasitic on Persea americana

Abstract

Objective To explore antidiabetic principles of the Eastern Nigeria mistletoe, Loranthus micranthus Linn. parasitic on Persea Americana.

Methods The weakly acidic fraction of the aqueous methanol extract of the leaves of Loranthus micranthus (Linn.) was isolated and tested for its antidiabetic activities. The isolation of the weakly acidic fraction was carried out following established physico-chemical based procedures. Furthermore, alloxan-induced diabetic rats were treated intraperitoneally (ip) with 250 mg/kg and 400 mg/kg of the weakly acidic fraction, glibenclamide 10 mg/kg (positive control) and 2 mg/kg of 3 % v/v tween 20 (negative control). The sugar levels of the treated and untreated animals were determined by withdrawing the blood at regular intervals and testing them with an automated glucometer. The phytochemical analysis of the acidic fraction was carried out using standard procedures. Chromatographic techniques were employed in the subsequent isolation and purification of the constituents of the weakly acidic fraction.

Results It was shown that the maximum effect of the weakly acidic fraction was obtained at 24 hours after administration and was found to be statistically comparable with that of the positive control. The phytochemical analysis revealed the presence of steroids, terpenoids, alkaloids, flavonoids, glycosides, carbohydrates, saponins, and acidic compounds in the crude extract and carbohydrates, flavonoids, terpenoids and oil in the weakly acidic fraction. Further purification of the weakly acidic fraction of the methanol extract using thin layer chromatography shows that toluene: methanol: diethyl amine (3:1:1) and chloroform: methanol: diethyl amine (9:1:1) are the best solvent system for the isolation of the various components of the weakly acidic fraction of the crude methanol extract of Loranthus micranthus.

Conclusions The present study has led to the conclusion that the weakly acidic fraction of the plant under study has the potent antidiabetic activity and that the various components can be isolated using basic chromatographic techniques.