Leaf microscopy, high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) analyses of Croton zambesicus Mll.-Arg. leaf (Family: Euphorbiaceae) in Nigeria

This study was done to get information on the chemical composition and the internal structure of the plant which could aid in its further characterization. The study is aimed at determining the epidermal leaf anatomy, HPLC of the hot water extract, chemical constituents of the oil from the leaves by GC-MS and chemo-microscopic properties of Croton zambesicus for proper identification of the plant. The leaf epidermal microscopy of C. zambesicus showed abundant trichome on the abaxial surface arising from a multi-cellular base and radiating radially and paracytic stomata were observed on the lower surface of the leaf. Chemo-microscopic analysis of the leaves showed the presence of cellulose, lignin, starch, oxalate crystals, tannin, oils, proteins and absence of mucilage. The physicochemical parameters evaluated on the leaves had moisture content of 4.10% and total ash value of 11.91%. HPLC analysis of the hot water extract revealed 12 peaks with number 3 having the highest peak of 93 mAU at 3.5 min. The GC-MS analysis of the oil of the leaves had 57 components. Caryophyllene had the highest percentage composition (15.53%) followed by Copaene (11.38%), Phellandrene (8.65%), 1,6-Octadien-3ol, 3,7-dimethyl (4.67%), Humulene (3.94%), Pinene (3.85%) and Ar-tumerone (3.41%).