PHYTOCHEMICAL AND INHIBITION STUDIES OF GARCINIA KOLA HECKEL (GUTTIFERAE) SEED EXTRACTS ON SOME KEY ENZYMES INVOLVED WITH DIABETES, A RESEARCH PROJECT TOPIC ON MICROBIOLOGY
ABSTRACT
Garcinia kola is an Angiosperm belonging to the family Guttiferae. It is known in commerce as bitter kola. The plant seeds have been used in the treatment of a wide range of diseases including diabetes, and its importance in folkloric medicine as a purgative, mastcatory, aphrodisiac etc. is eminent. Diabetes mellitus is a metabolic disorder of multiple etiologies characterized by chronic hyperglycemia leading to severe complications such as neuropathy, nephropathy, retinopathy and foot ulcer. n-Hexane, ethyl acetate and methanol extracts were prepared successively in a soxhlet apparatus at 50ºC. Qualitative phytochemical screening was carried out. Column chromatographic analysis was carried out on the ethyl acetate extract and the structure of the isolated compound was elucidated via Gas Chromatography-Mass Spectrophotometry and Fourier Transformed-Infra Red spectroscopy. Pancreatic α-amylase and intestinal α-glucosidase were extracted from porcine pancrease and rat small intestine under specified conditions. Steroids/triterpenes, phenolics, flavonoids, cardiac glycosides, alkaloids, coumarins and phlobatannins were detected. Methanol, ethyl acetate and n-hexane extracts inhibited α-amylase with IC50 = 0.78 ± 0.32 mg/ml, 3.44 ± 3.46 mg/ml, 4.89 ± 4.62 and α-glucosidase IC50 = 2.67 ± 0.74 mg/ml, 1.68 ± 1.27 mg/ml, 10.29 ± 4.08 mg/ml respectively. The compound ZAAK was isolated from ethyl acetate extract. Fourier Transformed-Infrared spectra revealed the presence of carboxylic acid and an ester in ZAAK. Total ion chromatogram of ZAAK revealed three major peaks corresponding to ZAAK1ZAAK2 and ZAAK3. The mass spectra identified ZAAK1 ZAAK2 and ZAAK3 as 1-pentadecanecarboxylic acid, (Z)-11-Octadecenoic acid and octadecanoic acid, 2-(2-hydroxyethoxy) ethyl ester respectively.
