Spectroscopic analysis and anti-inflammatory effects of Milicia excelsa (Moraceae) leaf and fractions

Abstract

This study evaluated the spectroscopic and anti-inflammatory properties of the ethanol leaf extract of Milicia excelsa and fractions. The anti-inflammatory activities of the extract and various organic fractions were investigated using bovine erythrocyte membrane stabilizing assay. Ultraviolet‐visible (UV-VIS) and Fourier transform-infrared (FT-IR) methods were used to detect the characteristic peak values and their functional groups. The results showed that the crude extract and ethyl acetate fraction showed minimum percentage inhibitions of 0.88 ± 0.30 and 72.05 ± 0.45% and maximum percentage inhibitions of 81.66 ± 0.23% and 99.07 ± 0.30% respectively compared to the standard anti-inflammatory drug (Indomethacin) which exhibited minimum and maximum percentage inhibitions of 52.64 ± 0.83 and 75.51 ± 1.52% respectively.  The UV-VIS profile showed the peaks ranging from 270 to 670 nm with the absorption values from 0.040 – 0.720 which could confirm the presence of aromatic compounds, alkaloids, flavonoids, unsaturated conjugated compounds in the plant.  In addition, the FT-IR revealed diagnostic peaks around 3570-3200, 3000-2800, 2865-2845, 2850-2815, 2820-2780,  2070-2000, 1630-1750, 1640-1450, 1340-1250, 1200-1000, 800-700 nm-1 which could confirm the presence of phenols/alcohol/carboxylic acids, alkanes, diazocompounds,  aldehyde /ketone/ amide/ester, alkenes/aromatic compounds, ethers/phosphate compounds, aliphatic/chloro compounds respectively in Milicia excelsa. This study therefore demonstrated that ethyl acetate fraction with the highest percentage inhibition contained bioactive principles that protected the erythrocyte membranes effectively from lyses and also exhibited both monophasic and biphasic modes. The study also produced the UV-VIS and FT-IR spectrum profile for Milicia excelsa leaf which could be used to identify the plant biomarkers and chemical markers.