Nutrient and Essential Oil Compositions of Heterotis rotundifolia Leaves

Abstract

This study evaluated the nutrient and essential oil compositions of Heterotis rotundifolia leaves. The leaves were carefully sorted and air-dried for 14 days at room temperature (20-25°C). The dried leaves were ground into powder using a grinding mill. Proximate composition, vitamins and physicochemical properties were analyzed using AOAC method while fatty acid and essential oil compositions were characterized using GC-MS. The proximate composition of the leaves showed higher carbohydrate content (80.97±0.03%) and moderate protein content (9.9±0.06%); while lipid (3.13±0.01%), fibre (1.30±0.01%), moisture (2.90±0.03%) and ash (1.89±0.02%) contents were low. Physicochemical properties of the oil revealed a high saponification value (238.43±0.84mg/KOH) and peroxide value (47.20±0.38mEq/kg). Fatty acid composition shows 83.69% saturated fatty acid with stearic acid (22.69±0.02%), myristic acid (18.54±0.01%) and palmitic acid (15.48±0.02%) as predominant fatty acids. Unsaturated fatty acid composition was 9.72% with oleic acid (9.49±0.04%) and linolenic acid (0.23±0.01%) as predominant fatty acids. Vitamin composition also revealed higher concentrations of vitamins C (695.57±0.20mg/kg), B6 (70.33±0.88mg/kg), A (61.67±0.02mg/kg) and D (26.08±0.06mg/kg). Essential oil composition revealed a total of 24 compounds which include; long chain fatty acid, fatty acid methyl esters, hydrocarbons and alcoholic compound amongst which Neophytadiene (14.427%), n-Hexadecanoic acid (14.148%) and squalene (11.258%) were present in substantial amount. The proximate and essential oil compositions, vitamin content and physicochemical characteristics suggest that H. rotundifolia leaves have potential nutritional and medicinal value to man and animals.