Membrane stabilizing activity of extracts and non-polar fractions of Cola lepidota K. Schum. fruit. (Malvaceae): A comparative study

Cola lepidota (Malvaceae), is a wild, under-utilized edible indigenous fruit tree found in the humid West and Central African forest. The present study investigates the membrane stabilizing (MS) activity of the extracts and partitioned fractions obtained from the pulp and seed of C. lepidota. Dried pulp and seeds were identified by a Botanist, pulverized and stored. The phytochemical constituents of the crude extract were analysed using standard method. Each sample was extracted using absolute ethanol and fractionated using N-hexane and dichloromethane. The MS activity of the crude extracts and their partitioned fractons were determined using the heat induced and hypotonic solution induced human erythrocytes hemolysis model at doses of 250, 500, 1000 and 2000 μg/ml. Qualitative phytochemical screening indicated the presence of flavonoids, glycosides, alkaloids, tannins, phenols and terpenoids as the major phytochemical constituents.The pulp ethanol crude extract (PECE), at 250, 500, 1000 and 2000 μg/ml inhibited heat induced lysis of the human red cell membrane with values of (37.89 , 42.90, 53.27, 67.33) %, while the seed were 7.39 %, 16.04 %, 20.53 % and 35.64 % respectively. The percentage inhibitions of lysis induced by hypotonic solution at 250, 500, 1000 and 2000 μg/ml of the fruit pulp were 43.07 %, 47.19 %, 46.88 % and 63.42 % while the seed were 38.18 %, 39.08 %, 47.50 % and 42.32 % respectively. The results obtained were comparable to that of the reference standards aspirin and diclofenac. The DCM fraction of the pulp showed a better activity among the fractions. It can be inferred that the extracts and fractions of C. lepidota pulp and seed contains principles that are capable of stabilizing human red blood cell membranes against hypotonic solution and heat induced lysis.