**2.14.** *Solenostemon* **genus**

*Solenostemon* genus is from *S. rotundifolius*; oleanolic acid was isolated as a major component [96].

**2.16.** *Teucrium* **genus**

**2.17.** *Vitex* **genus**

**3. Conclusion**

for human benefits.

(grant No. 106055).

**Author details**

Ahmed A. Hussein

Western Cape, South Africa

**Conflict of interest**

The author declares no conflict of interest to disclose.

Address all correspondence to: mohammedam@cput.ac.za

**Acknowledgements**

most active IC50: 2.39 ± 0.64 μg/mL [106].

Three species were recorded in SA. From *T. africanum*tafricanins A (**218**) and B(**219**), teutrifi-

Chemistry of South African Lamiaceae: Structures and Biological Activity of Terpenoids

http://dx.doi.org/10.5772/intechopen.77399

29

*Vitex* genus is represented by 12 species in SA. The fraction responsible for antimicrobial activity of *V. rehmannii* was purified to give a labdane diterpene as an inseparable epimeric mixture of 12*S*,16*S*/*R*-dihydroxy-*ent*-labda-7,13-dien-15,16-olide (**222**). The extract and the labdane diterpene exhibited good antimalarial activity, with the labdane diterpene being the

South African flora characterized by high endemism and unique floral kingdom is only located in the great cape region. Lamiaceae is represented by ~308 species widely distributed all over the country. In general, the bioprospecting of SA flora including Lamiaceae is not reached; yet the required level and more attention are required to explore the potential of their chemical constituents. The present work shades the light on the isolated terpenoids of all listed species in updated SA flora checklist. It is interesting to indicate that *Plectranthus* genus contains mostly abietane diterpenes and shows potent activity as demonstrated by coleon U and parviflorons F and D. On the other hand, leoleorin C from *L. Leonurus* showed moderate binding affinity (*Ki* = 2.9 μM) to the Sigma 1 receptor. These compounds and others may be considered as a model for drug discovery

Cape Peninsula University of Technology and National Research Foundation, South Africa,

Chemistry Department, Cape peninsula University of Technology, Bellville Campus,

din (**220**) and 4*α*,18-epoxytafricanin A (**221**) were isolated [105].

### **2.15.** *Tetradenia* **genus**

Seven species were recorded in SA, one of them *T. riparia* is widely distributed in Africa and showed interesting chemical profile. Several compounds have been isolated from the leaves of this plant, including 8(14),15-sandaracopimaradiene-7*α*,18-diol (**214**) [97], 8(14), 15-sandaracopimaradiene-2*α*,18-diol (**215**) [98], 9*β*,13*β*-epoxy-7-abietene (**216**), 6,7-dehydroroyleanone (**136**) [99], and ibozol (**217**) [100].

Compound (**214**) exhibited antimicrobial activity (**213**). Compound (**215**) showed papaverinelike antispasmodic activity on guinea pig ileum contracted by methacholine, histamine, or BaCl2 and on the noradrenaline-induced contractions of rabbit aorta [101]. It also showed activities against *Trichomonasvulgaris* with MIC of 20–40 μg/mL [102], wheat rootlets inhibition activity (MIC7.81 μg/mL) [103], and *M. tuberculosis*[104].
