Justification of the Study
Uapaca staudtii is employed traditionally in the treatment of disease conditions such as wound, inflammation and diarrhea. Furthermore, there is no literature report on anti-inflammatory, analgesic as well as chemistry of the plant. Hence it is necessary to carry out research study to ascertain the potency and safety of this medicinal plant in the management of pains and inflammation associated with wound. Chemical constituents responsible for the activities may lead to potent or even novel Compounds.
The aim and objectives of the study include:
To carry out chemical and anti-inflammatory studies of U. staudtii leaves in rodents.
To carry out the phytochemical analysis of the ethanolic extract of U. staudtii leaves.
To determine the median lethal dose (LD50) of the ethanolic extract in order to predict the dose and safety of the extract.
To study the dose-response anti-inflammatory and analgesic effect of the extract and fraction of U. staudtii leaves.
To investigate the possible mechanism of anti-inflammatory and analgesic effect.
Purification and isolation of bioactive compounds responsible for these pharmacologic actions.
Characterization of active constituents isolated using various spectroscopic techniques such as Ultraviolet (UV), Infrared (IR), Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS).
Preparation and Extraction of Plant Material
The leaves were destalked, washed, air dried and pulverized. The powdered plant material was weighed and about 2.8 kg was extracted cold with 22 L of 50% ethanol and shaken intermittently for 72 hours at room temperature. After 72 hours, the liquid extract concentrated in vacuo using rotary evaporator at 45oC. The extract was further concentrated to dryness in a water bath at 50oC and weighed. The dried extract (450 g) was stored in a refrigerator until use.
The phytochemical screening was carried out on the ethanol extract of U. staudtii leaves according to standard methods to preliminary identify the classes of bioactive compounds in the plant extract.
About 0.5 g of the extract was stirred with 5ml of 5% hydrochloric acid in a test tube placed on a steam bath at 100oC. The mixture was filtered and divided into three portions of 1ml each. The first portion of the filtrate was treated with few drops of Meyer’s reagent while the second portion was treated with Dragendorff’s reagent. Precipitation or turbidity with these reagents was taken as the preliminary evidence for the presence of alkaloids in the extract. The third portion of the filtrate was treated with few drops of picric acid; a yellow precipitation was taken as preliminary evidence for the presence of alkaloids (Harborne, 1998; Sofowora, 1993).
Free Anthraquinone:About 0.5 g of plant extract was treated with 2ml of benzene, filtered and 0.5 ml of 10% ammonia solution added and shaken. The presence of pink, red or violet colour in the ammonical layer indicated the presence of free hydroxy anthraquinones (Sofowora, 1993).
