**3.8** *Pittosporum viridiflorum Sims*

*P. viridiflorum*, a *Pittosporaceae* family member, is found throughout the eastern half of South Africa (Eastern, P. viridiflorum, a Pittosporaceae family member, is found throughout the eastern half of South Africa (Eastern), from the Western Cape up into tropical Africa and beyond to Arabia and India [51]. *P. viridiflorum* can grow from a small shrub to a large forest tree up to 30 m tall. The bark is pale brown to grayish, with distinct white dots (lenticels). It has glossy, dark green leaves that are typically wider above the center. In early summer (November to December), small, greenish white, sweetly scented flowers bloom [51]. Following them are small yellowbrown seed capsules. When the capsules are broken open, a slew of small, shiny, orange-red seeds emerge, each encased in a sticky, resinous exudate (**Figure 10**). This cheese wood is frequently confused with white milkwood [51].

The vernacular plant among South African ethnic groups are Southern Sotho (Sesotho) (Mosetlela), Afrikaans (Witboekenhout, Kaarsuur, Bosbeukenhout,

**Figure 10.** *Pittosporum viridiflorum Sims - http://pza.sanbi.org/pittosporum-viridiflorum.*

#### *South African Herbs Used for Cancer Therapy in Rural Areas DOI: http://dx.doi.org/10.5772/intechopen.108734*

Bosboekenhout Kersuurboom, Kasuur), English (cheesewood, Umkwenkwe, White Cape Beech), Northern Sotho (Kgalagangwe), Tswana (Mpustinyapoqo, Nkasur), Venda (Mulondwane, Mutanzwakhamelo), Zulu (umfusamvu, Umkhwenkwe, Umphushamvu Umphushane, Umvusamvu), Xhoza (Umgqwengqwe, Umkhwenkwe [52].

Traditionally the root or bark decoctions are administered orally in the Eastern Cape province [5]. Another scientific study has reported that the bitter taste and strong resinous or liquorice smell bark is used medicinally, and it possess positive anticancer activity against human prostate cancer [53]. Dried, powdered root or bark is sometimes added to beer as an aphrodisiac [5]. Traditional healers should practice great caution when using this plant, *P. viridiflorum* has been scientifically found to have moderate to significant toxicity against cancer cells in the laboratory [54–56]. A similar kind of toxicity was observed scientifically when tested Swiss mice study which ranged from low toxicity on bark to killing of the mices in 24 hours by leaf extract [56, 57].

#### **3.9** *Knowltonia capensis (L.) Huth*

*Knowltonia capensis (L.) Huth* is a slow-growing, stemless perennial herb that grows between 300 and 500 mm tall and belongs to the *Ranunculaceae* family. Flowers are made up of colored sepals rather than petals (this distinguishes it from Ranunculus). In winter and spring, it has a 450 mm long flowering stem with a compound umbel of creamy-green flowers (from June to September). These are followed by fruits, which are small, fleshy berries in dense clusters that are green when ripe and turn black when fully ripe. There is a short rhizome with fleshy roots (**Figure 11**). The tooth-edged, basal leaves are distinctive, being tough, coarse, and leathery in texture. They are usually trifoliately compound, that is, divided into three distinct leaflets, with the middle leaflet being slightly larger than the two on the side. *Anemone knowltonia* is found in coastal bush and forested kloofs and grows along forest margins. This plant is most common in East London, from which it spreads eastward to the KwaZulu-Natal midlands and westward to the Cape Peninsula. Because it has a rhizome, it will most likely be able to withstand frost, and due to its wide distribution range, it can withstand both high and low rainfall [58].

Traditionally healers collect and dry the corms, this normally followed by crushing the corms which will be taken orally with water to treat cancer or in the form of

**Figure 11.** *Knowltonia capensis (L.) Huth-http://pza.sanbi.org/knowltonia-capensis-0.*

decoction until the patient is cured [5]. There is no scientific study reported toxicity related to cancer cells on this plant thus far.
