The effect of desiccation on lipid content, fatty acid composition and the antioxidative enzymic capacity was investigated in seeds of Telfairia occidentalis, harvested at physiological and agronomic maturity. Seeds were dried at 5 and 28 o C, environments that induced different drying and metabolic rates. Desiccation of seeds was associated with decreased antioxidative enzymic capacity (of peroxidase and polyphenoloxidase), and thus increased likelihood of free radical attack and decreased viability (germinability). Agronomically mature seeds contained predominantly saturated fatty acids (tridecanoic), with very low levels of the major fatty acids of edible oilseeds (palmitic, stearic or the unsaturated C18 fatty acids). There was increased accumulation of the mono-unsaturated (oleic) and polyunsaturated (linoleic) fatty acids when seeds were dried at 28 o C and moisture contents have reduced to about 42 % or lower. In contrast, seeds dried at 5 o C maintained high levels of saturated fatty acids and lower levels of monounsaturated or polyunsaturated fatty acids. Results suggest the need to develop different post-harvest protocols for seed storage, and for processing T. occidentalis to 'improve' the seed fatty acid profile as an oilseed for human and animal food.

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The loss of Africa's forests and bioresources is occurring at an alarming rate, a consequence of increasing population pressure, agricultural land degradation, urbanization and neglect. There is a growing recognition worldwide that conservation and sustainable management of bioresources are pressing priorities in the world today. The choice of conservation methods and techniques depend on the objectives of the particular conservation effort, the breeding system and behaviour of the species in question as well as the available resources including funds, trained personnel, infrastructure and technologies. The use of biotechnological tools and "bioprospecting" will open new vistas in medicine, agriculture, silviculture, horticulture, environment and other important issues. This paper reviews some biotechnological tools that could be harnessed in promoting conservation and sustainable use of bioresources.

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Seeds of S. tryonii require an after-ripening period for germination.