Geography and distribution
South Africa and Namibia. Description
Hoodia gordonii is a cactus-like, clump-forming, spiny succulent to 75 cm tall, lacking conventional leaves. Flowers are up to 10 cm in diameter, more or less circular to clearly 5-lobed, flesh-coloured or a deeper reddish purple. The fruit is a V-shaped pair of cylindrical follicles, up to about 12 cm in length. Threats and conservation
This species is threatened by succulent-plant enthusiasts taking wild plants for their collections, and by people collecting it for its therapeutic value. It is also under pressure from browsing and grazing. Hoodia species are now the subject of intensive bioprospecting and harvesting from the wild. Efforts are underway to regulate wild harvesting. Uses
Several species of Hoodia (including H. gordonii , H. pilifera and H. currorii ) have been used as food by African tribespeople in Botswana, Namibia, Angola and South Africa. It is reported they ate the young peeled shoots as a food to quench their thirst on long hunting trips. Once Hoodia gordonii had been shown to have appetite-suppressant activity, researchers at the Council for Industrial Research (CSIR) in South Africa worked on the chemistry of the plants and identified the active principle as a pregnane glycoside (P57). In 1998 the CSIR protected the use of this compound as an appetite-suppressant by filing a patent and licensing its subsequent development of the patent through an intermediary, first to a pharmaceutical, and then a food company.
The San people demanded recognition of their traditional knowledge and a share of the benefits that would arise from the development of slimming products that contained P57. This agreement was signed in 2003. In 2008, the food company Unilever decided to drop its plans to develop Hoodia as part of its range of slimming products. Phytopharm, the UK company that had licensed the development of Hoodia to Unilever, is hoping to develop the product with another international company. Hoodia products are currently been sold via websites but care should be taken when purchasing these as laboratory studies have shown that some do not contain Hoodia .
H. gordonii has several uses as a traditional medicine, including the treatment of hypertension, diabetes, tuberculosis and abdominal pains. To date, patents have also been filed on the anti-diabetic activity of Hoodia and for its use in the treatment of gastric acid secretion damage. Despite the fact that research on Hoodia as a food resulted in commercial interest, the nutritive value of Hoodia still requires further investigation.
Hoodias also make attractive and unusual ornamental plants for tropical arid gardens, or as greenhouse subjects in temperate countries. Care should be taken to ensure plants are from cultivated sources, and not obtained directly from the wild. Millennium Seed Bank: Seed storage
Kew's Millennium Seed Bank Partnership aims to save plant life world wide, focusing on plants under threat and those of most use in the future. Seeds are dried, packaged and stored at a sub-zero temperature in our seed bank vault.
Number of seed collections stored in the Millennium Seed Bank: One
Germination testing: Successful Cultivation
This is a slightly challenging plant to cultivate as it can rot off at the base if overwatered, thus causing the plant to collapse. Therefore, careful watering, allowing compost to dry out fully between waterings, is important.
Potting compost needs to be gritty or sandy and well drained. It also needs good, bright light. At Kew, Hoodia gordonii is grown under glass in pots plunged in a heated sand bench all year round, but it could be grown in a warm conservatory or greenhouse.
Hoodia gordonii is easiest grown from seed. At Kew the sealed bag method is used for germinating many succulents. Seeds are sown on top of moist sterilised compost and covered lightly with fine grit to anchor them. The pot is then placed in a transparent plastic bag and sealed with a rubber band. They can be left inside sealed bag for months until pricking out size.
Alternatively try rooting Hoodia cuttings by slashing the cut base of a cutting and soaking in rooting hormone. Allow the cut surface to callus well and place on slightly damp medium to root (Kew uses Seramis). It can still be difficult to get them to root.
Another alternative is to try grafting cuttings onto Ceropegia tubers.