Potential Application of the West African frankincense, Boswellia dalzielii Hutch, for Drug and Perfumery Products
Abstract
Taiwo E. Alemika, Olalekan S Ojerinde, Opeyemi Balogun and Yves S Kafuti
Boswellia dalzielii is the West African species of the frankincense producing genus (B. carterii, B. frereana and B. serrata are the more popular congeners). Its ethnobotanical uses include the treatment of rheumatism, venereal diseases and gastro-intestinal disorders, among others.Scientific investigations were carried out to evaluate the biological properties relevant to their ethnomedical uses and to better understand the chemistry of the plant. This is with a view to identifying possible applications for medicinal, cosmetic and industrial purposes. The stem bark was subjected to solvent extraction and activity-directed fractionation to isolate bioactive compounds. The isolated compounds were characterised using joint spectroscopic techniques, including 2-D NMR and Mass Spectrometry. The gum resin was steam-distilled to obtain volatile oil, which was analysed by GC-MS. Another portion of gum resin was also extracted by organic solvent and fractionated by column chromatography. From the results obtained; the antimicrobial/antioxidant activity of the stem bark was accounted for by isolated compounds – protocatechuic acid, gallic acid and ethyl gallate with minor contribution from a novel stilbene glycoside and a cembranediterpenoid (incensole). The extracts also demonstrated antifungal, anti-inflammatory, cytotoxic and hypoglycemic effects. The gum resin (frankincense) showed anti-inflammatory activity and yielded volatile oil consisting mainly of monoterpenes (fragrant essence). The gum resin extract yielded incensole and 3-O-acetyl-11-ketoboswellic acid (AKBA). The spectrum of biological activities observed justifies the ethnomedical uses and suggests great potential for further drug development. The essential oil can be employed in perfumery products and in related industry.