Assessment of physicochemical properties of Globimetula braunii (Loranthaceae) leaf extracts

Abstract

Purpose: This study is aimed at assessing the physicochemical properties of the leaves, ethanolic leaf extract (GBE), petroleum ether fraction (PEF) and n-butanol fraction (NBF) of Globimetula braunii leaves. Methods: Physicochemical tests such as moisture content, pH, total ash, acid insoluble ash, water/alcohol soluble extractives and heavy metal limit tests were conducted on the leaf powder. GBE was partitioned with petroleum ether, ethyl acetate and n-butanol to get PEF, EAF and NBF fractions respectively. GBE, PEF and NBF were assessed for solubility, maximum wave length of absorption, moisture and light stability tests. Quality control test such as microscopy, chromatographic fingerprints and infrared spectra of NBF and PEF were carried out. Results: GBE yield was 10.22 % w/w while PEF, EAF and NBF fractions yielded 3.8 %, 6.59 % and 14.21 % w/w respectively. The pH of the leaf powder, GBE, PEF and NBF were 6.24, 6.24, 6.20 and 6.25 respectively. GBE and NBF were sticky while PEF was oily in texture. The physicochemical tests results of the leaf powder indicated low levels of inorganic matter, silica and low levels of contamination by earth and heavy metals. The light absorption exhibited a maximum only at 227 nm. There was a visible colour change of GBE, PEF and NBF on exposure to UV light. The moisture uptake test values increased from 30 % RH to 90 % RH (GBE>NBF>PEF). Conclusion: The outcome of the physicochemical tests gives an insight into the possible formulation approach of GBE, PEF and NBF into dosage forms. Keywords: G. braunii, petroleum ether, n-butanol fractions, antihyperglyceamic property