Characterisation and Hypolipidaemic Activity of Phenylquinoline, and Narceine Isolated from Ficus polita Leaf

Aim: To evaluate hypolipidaemic potentials of column chromatography fractions (F1 to F6) of the chloroform leaf extract of Ficus polita and to detect the bioactive compounds present in the most active fraction using spectroscopic techniques.

Study Design: Fourty-five (45) wistar rats were grouped into nine groups of five rats each: normal control, hyperlipidaemic control, hyperlipidaemic administered with standard drug control/ atorvastatin (10 mg/kg body weight), and hyperlipidaemic administered groups administered with 50 mg/kg body weight of column chromatography fractions (F1, F2, F3, F4, F5, and F6) for a period of two weeks.

Place and Duration of Study: Department of Biochemistry Laboratory, Faculty of Basic Medical Sciences, Bayero University Kano, Nigeria, from May 2018 to April 2019.

Methodology: Chloroform leaf extract of F. polita was fractionated by using column chromatography, and the resulting fractions were pooled, based on their retention factor (Rf), into six (6) fractions by using analytical thin layer chromatography. The resulting six (6) fractions were screened for hypolipidaemic activity. Serum total cholesterol (TC), triglycerides (TG), high density lipoprotein-cholesterol (HDL), and low density lipoprotein cholesterol (LDL) were determined. The rats treated with the best fraction in terms hypolipidaemic activity (fraction 3) were screened for serum HMG Co A reductase, lactate dehydrogenase (LDH), creatine kinase (CK) activities, as well as troponin I level. Oxidative stress markers such as malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) were determined in the heart tissue homogenate of the rats treated with fraction 3.

Results: Fraction 3 treated hyperlipidaemic group showed significant (p<0.05) decrease in the levels of serum TC, TG, and LDL, but significant (p<0.05) increase in the level of serum HDL. Fraction 3 (F3) treated hyperlipidaemic groups showed significant (p<0.05) decrease in the activity of serum LDH and the level of troponin I, but significant (p<0.05) increase in the activity of serum HMG Co A reductase. After high fat diet administration, the level of heart tissue antioxidant markers such as GSH, SOD and catalase were decreased whereas the level of heart tissue MDA was elevated. The level of these antioxidant markers were brought to normalcy by fraction 3 (F3). Histological studies of the heart corroborated the biochemical findings, and treatment with fraction 3 (F3) was found to be effective in restoring dietary-induced myocardiac toxicity in rats. FTIR and GCMS analyses were carried out for the detection of bioactive compound(s) in fraction 3 (F3), and the result revealed the presence of "8-methoxy-4-phenylquinoline, and narceine.

Conclusion: The study concludes that; the hypolipidaemic property of the leaf of F. polita is mediated by the bioactive compounds "8-methoxy-4-phenylquinoline, and narceine." via their antioxidant properties.