Chem. Pharm. Bull. 52(6) 649—653 (2004)

southern part of Nigeria and other west African nations. Examinations of the liver, kidney and duodenum of rats fed a diet containing 10% w/w of dry powdered seed of the kola for 6 weeks has been reported as revealing some useful histological alterations in these organs. In some Nigerian houses it is served as a substitute for the true kola nuts (Cola nitida and Cola acuminata). It has a bitter astringent taste when chewed resembling that of raw coffee bean, followed by a slight sweetness. The bitter taste gained the seed its common name “bitter Kola”. It also enhances the flavour of some local beverages. It is an economic and highly valued tree used extensively in African traditional medicine for the treatment of various diseases. The extracts of the seeds are claimed to have some antimicrobial property and have been used in the preparation of cough mixture. The seed has been used in local medicine to relieve coughs, colic, headache, chest colds and hoarseness hence improving singing voice. The seed is also used in the treatment of bronchitis, throat troubles, post partum hemorrhage, urinary tract infections and emesis. Garcinia kola and other members of the genus are known to elaborate a complex mixture of phenolic compounds including biflavonoids, xanthones and benzophenones. Some of these constituents were reported to possess antihepatotoxic activity against a variety of experimental hepatotoxins. It is used in the treatment of liver cirrhosis. Formulation of Garcinia kola into a tablet dosage form might ensure dosage precision, since herbal medicines have been widely criticized due to lack of standardization. Also formulation of Garcinia kola into a modern pharmaceutical conventional tablet dosage form would confer into it many of the good properties of tablets. Some examples include ease of administration, greater acceptance due to presentation, prolonged shelf life, quality assurance, greater accuracy in dispensing and reduction in transportation cost arising perhaps from formulation into less bulky dosage form. This research is aimed at producing standardized conventional tablet dosage forms of powdered Garcinia kola seeds and extracts and evaluating the various tablet properties. Experimental The following materials were used without further purification; aluminum chloride and ethanol (Merck), starch, acacia, gelatin, and magnesium stearate (BDH, chemicals), lactose and sodium carboxymethyl cellulose (Aqualon). The following B. P. reagents were obtained from laboratory stocks: Fehlings solution A and B; Dragendorffs reagent, and picric acid solution. Methods. Collection of Material Garcinia kola seeds were purchased from Nsukka market. The seeds were peeled, cut into pieces and dried in an oven at 40 °C for 48 h. The dried seeds were ground to a fine powder. The powdered material was divided into two. The first portion was used for tabletting as such while the second portion was extracted and extract used for tabletting. Extraction of the Powdered Seeds The powder of Garcinia kola was transferred into a soxhlet apparatus (extractor). The fine powder (1.5 kg) was placed in a soxhlet extractor and extracted with ethanol for 18 h. The extract so obtained was concentrated to a semi-solid mass using a rotary evaporator. A dry mass was obtained by adsorbing the concentrate on maize starch (146.4 g) and drying the mixture at 50 °C for 24 h. The total yield of the extract was 73.2 g while the total mixture was 219.6 g. The adsorbent to the extract ratio was 2 : 1. Phytochemical Analysis The following tests were performed on the ethanolic and aqueous extracts of the dried, seeds. Test for starch was performed by means of iodine. Millon’s reagent was used to test for proteins while the test for alkaloids was performed using Wagner and Dragendorff’s reagents. Other tests included Fehlings solution for glycosides, ferric chloride test for tannins, Carrs-price test for sterols and triterpenoids and the blood haemolysis test for saponins. The presence of flavonoids was detected using NH4OH. The results of the tests are presented in Table 1. Assay of Garcinia kola Seed The assay procedure was carried out on both the dried, powdered seed and the crude ethanolic extract. These samples were used for the determination of rutin-like flavonoids present in the seed. A Beer’s calibration curve for rutin was employed as the standard. June 2004 Chem. Pharm. Bull. 52(6) 649—653 (2004) 649