**6. Triterpenes**

A major class of secondary metabolites are known as triterpenes and it usually contains 30 carbon atoms consisting of 6 isoprene units (**Figure 6**). It is derived from the squalene biosynthetic pathway. Triterpenes have many methyl groups and it can be oxidized into alcohols, aldehydes, and carboxylic acids, which make it complex and differentiate it biologically. Triterpenes have many active sites for the glycosylation which converts it into another big class of compounds, namely, saponins (triterpene glycoside). Herein, we are discussing some recently published bioactive triterpenes (**Table 5**).

**7. Meroterpenes**

**Figure 7.** Structures of meroterpenes.

Xuedanencins G

Cyclocariols A, B,

and H

and H

Polyporenic acid B Fruiting bodies of

*Fomitopsis palustris*

Tubers of *Hemsleya penxianensis*

Leaves of *Cyclocarya* 

*paliurus*

**Table 5.** Source and biological activities of some triterpenes.

Meroterpenes are the secondary metabolites with partial terpenoid skeleton. Meroterpenoids were partially derived from mevalonic acid pathways and widely derived from animals, plants,

**Names Plant source Activity Ref.**

Pardinol B *Tricholoma pardinum* Compound showed strong cytotoxicity against HL-60

Pardinol E *T.* pardinum E exhibited strong cytotoxicity against HL-60 SMMC-

respectively

respectively.

Pardinol F *T. pardinum* F showed strong cytotoxicity against HL-60 SMMC-7721

12.2 μM, respectively.

15.0 μM, respectively.

2.45 μM, respectively.

It showed strong cytotoxicity against the HCT116, A549, and HepG2 cell lines with IC50 values of 8.4, 12.1, and

Introductory Chapter: Terpenes and Terpenoids http://dx.doi.org/10.5772/intechopen.79683

SMMC-7721 A-549 MCF-7 SW480, 8.3, 15.0, 14.4, 12.7,

7721 A-549 MCF-7 SW480, 9.8, 11.7, 9.8 11.9, 15.6, μM,

A-549 MCF-7 SW480, 11.2, 15.6, 12.6, 10.5, 14.1 μM,

G and H were evaluated for cytotoxic activity against the Hela human cancer cell line and compounds showed significant cytotoxicity with IC50 value at 1.82 and

A, B, and H were tested against human colon tumor (HCT-116) cell lines, exhibited good activities with IC50 values of 6.53, 4.94, and 6.48 μM, respectively.

[17]

9

[18]

[18]

[18]

[19]

[20]

**Figure 6.** Structure of triterpenes.


**Table 5.** Source and biological activities of some triterpenes.
