Cultivation practices and manufacturing processes to produce Hoodia gordonii extract for weight management products.

Hoodia gordonii (Masson) Sweet ex Decne., is a succulent shrub, indigenous to the arid regions of southern Africa. Indigenous people have historically utilised certain species of Hoodia, including H. gordonii, as a source of food and water. Studies by the Council for Scientific and Industrial Research (CSIR, South Africa) identified that extracts of H. gordonii had appetite suppressant activity associated with specific steroid glycosides. A programme to develop weight management products based around this discovery was implemented in 1998. An agronomy programme was established which demonstrated that it was possible to cultivate this novel crop on a commercial scale (in excess of 70 ha). In parallel, a food grade manufacturing process was developed consisting of four main steps: harvesting of H. gordonii plant stems, comminution, drying under controlled conditions and extraction using food grade solvents. Appropriate Quality Control (QC) procedures were developed. The extraction process is capable of delivering a consistent composition despite natural variations in the composition of the dried H. gordonii. Specifications were developed for the resulting extract. The intended use of the standardised H. gordonii extract was as a functional food ingredient for weight management products. Other development studies on characterisation, toxicology and pharmacology are reported separately.

Quantification of appetite suppressing steroid glycosides from Hoodia gordonii in dried plant material, purified extracts and food products using HPLC-UV and HPLC-MS methods.

High-performance liquid chromatography (HPLC)-UV and HPLC-Mass Spectrometry (MS) methods were developed for the quantitative analysis of the family of Hoodia gordonii steroid glycosides with appetite suppressing properties in dried plant material, in purified and enriched extracts and in various prototype food-products fortified with H. gordonii extracts. For solid materials, e.g. dried plants or for non-fatty foods, extraction of the steroid glycosides is performed using methanol. For products where the steroid glycosides are present in an oil matrix, direct injection of the oil after dilution in tetrahydrofuran is applied. The HPLC separation is performed on an octyl-modified reversed-phase column in the gradient mode with UV detection at lambda = 220 nm. Quantification is performed against an external calibration line prepared using either one of the pure steroid glycosides or geranyl-tiglate. Short- and long-term repeatabilities of the methods are better than 3 and 6%, respectively. Recoveries are better than 85%, even in the analysis of the least abundant steroid glycosides in a complex yoghurt drink. Linearity is better than 3-4 orders of magnitude and the detection limits are below approximately 2 microg g(-1) for the individual steroid glycosides in dried plant material and food products. HPLC-MS is used to confirm that the steroid glycosides contain the characteristic steroid core, the carbohydrate chain and the tigloyl group.