13 Assessment of the Antidiabetic Potential of an Aqueous Extract of Honeybush (Cyclopia intermedia) in Streptozotocin and Obese Insulin Resistant Wistar Rats Christo J.F. Muller 1 , Elizabeth Joubert 2,3 , Kwazi Gabuza 1 , Dalene de Beer 2 , Stephen J. Fey 4 and Johan Louw 1 1 Diabetes Discovery Platform, Medical Research Council (MRC), Cape Town, 2 Post-Harvest and Wine Technology Division, Agricultural Research Council (ARC), Infruitec-Nietvoorbij, Stellenbosch, 3 Department of Food Science, Stellenbosch University, Stellenbosch, 4 Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, 1,2,3 South Africa 4 Denmark 1. Introduction It has been estimated that diabetes will affect 439 million adults by 2030, with the major increase occurring in developing countries (Shaw et al., 2010). It is projected that it will rank as the 9th leading cause of death in low-income countries (Mathers & Loncar, 2006). There are two major types of diabetes, i.e. type 1 (T1D) or insulin dependent diabetes and type 2 (T2D) or non-insulin dependent diabetes. The incidence of T2D is reaching epidemic proportions and has been associated with an increase in obesity (Venables & Jeukendrup, 2009). According to the World Health Organisation (WHO, 2011) the main complications associated with diabetes are cardiovascular disease and renal failure. Although genetic factors may play a role, life-style factors, such as reduced exercise and poor diet, specifically a high carbohydrate, high fat diet devoid or low in fruit and vegetables, have been shown to increase the risk of diabetes (Astrup, 2001). Medicinal plants have been used in folk medicine and traditional healing systems such as Ayurveda and Traditional Chinese Medicine (TCM) for the treatment of diabetes (T.S.C. Li, 2003; Modak et al., 2007; Singh et al., 2009; Yen et al., 2003). On the African continent as many as 90% of the populations of some countries relies on plants as the principal source of medicine for the treatment of different diseases, including diabetes (Hostettman et al., 2000), as they provide an affordable alternative to drugs. In South Africa a large number of plants, belonging to plant families such as the Asteraceae and Lamiaceae, amongst others, have been traditionally used for the treatment of diabetes (Deutschländer et al., 2009; Erasto et al., 2005; Thring & Weitz, 2006). www.intechopen.com