Gas Chromatography – Mass Spectrometry Identification of Bioactive Compounds in Methanol and Aqueous Seed Extracts of <i>Azanza garckeana</i> Fruits

Abstract

Azanza garckeana is a tropical fruit plant found in Africa. Its edible fruit is used as food or herbal medicines, while the seeds are discarded. In an attempt to turn waste to wealth and obtain useful substances from it, this study was carried out to identify the bioactive compounds with nutritional and health-promoting benefits present in methanol and aqueous extracts of the seeds of this fruit. Freshly harvested few fruits of A. garckeana containing the seeds were obtained from Tula in Kaltungo LGA, Gombe State, Nigeria. They were identified and authenticated at the Forest Research Institute of Nigeria (FRIN), Ibadan, Nigeria. The pulverized seeds were used to obtain methanol and aqueous extracts and subjected to GC-MS analysis. The results of the study revealed the presence of thirtyeight bioactive compounds which have been reported to have anticancer, antioxidant, antimicrobial, anti-androgenic, anti-inflammatory and hepatoprotective properties. Among these compounds are the following with reported biological functions namely: Pentadecanoic acid, Octadecadienoic acid, Hexadecanoic acid, Tetradecanoic acid, Heneicosane, 2-Methyltetracosane and Methyl stearate. There concentrations range from 0.33% for 9-Octadecenoic acid-methyl ester (Methyl oleate) to 24.3% for 9,12– octadecadienoic acid-(z-z) (Linoleic acid) in methanol extract. In the aqueous extract, the bioactive components measured 0.18% (lowest) for Dodecane, 2,6,11-trimethyl- and 2-Methyltetracosane (Isopentacosone) to 7.34% (highest) for 9-Octadecenoic acid (Z)- (Oleic acid). Other compounds without known reported functions are 10,13-Octadecadienoic acid, 9-Octadecenoic acid 12-hydroxy-methyl ester [R-(Z)]- and 1,13-Tetradecadiene among others. The seeds of A. garckeana have useful constituents that can be exploited for health benefits.