The Role of Plant-Based Natural Compounds in Inflammation
Namrita Lall in Medicinal Plants for Cosmetics, Health and Diseases, 2022
Triterpenes (Figure 22.6) are composed of three terpene units and include steroids, bile acids and saponins (triterpene glycosides). Among anti-inflammatory triterpenes, boswellic acids (BAs) have long been known as non-competitive and non-redox 5-LOX inhibitors (Safayhi et al., 1992). BAs are the main components of an anti-inflammatory remedy, frankincense, a resin obtained from the bark of Boswellia species, such as Boswellia serrata Roxb.ex Colebr., B. sacra Fluck (Figure 22.7A–B), B. carterii Birdw, B. papyrifera Hochst. or B. frereana Birdw. (Verhoff et al., 2014). The main structural features of BAs, important for their 5-LOX activity, include a pentacyclic triterpene ring structure, hydrophilic groups at the C4 position of the A-ring and an 11-keto group (Sharma and Jana, 2020). Especially, 3-O-acetyl-11-keto-β-boswellic acid (AKBA) has been extensively studied over the years and its reported IC50 values for 5-LOX inhibition range between 8 µM and 50 µM in cell-free assays and between 1.5 µM and 15 µM in cell-based assays (Werz, 2007).
Ursolic Acid: A Pentacyclic Triterpene from Plants in Nanomedicine
Mahfoozur Rahman, Sarwar Beg, Mazin A. Zamzami, Hani Choudhry, Aftab Ahmad, Khalid S. Alharbi in Biomarkers as Targeted Herbal Drug Discovery, 2022
Ursolic acid (UA) is a naturally derived pentacyclic triterpenoid, an important bioactive phytochemical. Ursolic acid is the most promising member of the triternenoid groups. Depending upon the quantities of different structural isoprene units, families of triterpenoids are classified. By squalene cyclization, these triterpenoids are synthesized which generally found in natural sources like many plants and fruits (Jager et al., 2009). Roots of Catharanthus trichophyllus, leaves of Plumeria obtuse, Eriobotrya japonica, and Rosmarinus officinalis, etc., are some source of UA (Shanmugam et al., 2013). Pentacyclic triterpenes, exhibit numerous biological functions due to the presence of different functional groups. It also possesses activity like cytotoxicity on different cancer cell lines. Having many potential benefits, some physical limitations restrict the oral and systemic delivery of UA (Jeong et al., 2007; Jager et al., 2008; Yin et al., 2012). To increase the solubility and to improve the bioactivity of UA, formulations like liposomes, nanoemulsions, nanoparticles (polymeric, solid, and metallic, among others) and cyclodextrin drug complexes, among other systems try to develop successfully (Jager et al., 2015; Xie et al., 2016; Li et al., 2015). The main focus of this chapter will be different evaluation techniques (in-vitro and in-vivo) regarding the antitumor effects of pentacyclic triternene, i.e., UA. Not only that, but the contribution of nanotechnology to facilitate the effective delivery of UA will be also concerned.
Ethnomedicinal and Pharmacological Importance of Glycyrrhiza glabra L
Mahendra Rai, Shandesh Bhattarai, Chistiane M. Feitosa in Wild Plants, 2020
Other triterpenes present are liquiritic acid, glycyrretol, glabrolide, isoglaborlide, and liquorice acid (Isbrucker and Burdock 2006). The root also contains an isoflavane known as Glabridin. EMA (2013) was the first to isolate 18β-glycyrrhizic acid from the roots of Glycyrrhiza glabra and he called 18β-glycyrrhizic acid as glycyrrhizin (EMA 2013). Glycyrrhizin is the major bioactive compound in the underground parts of Glycyrrhiza plants, which possess a wide range of pharmacological properties, and are used worldwide as a natural sweetener. Due to its economic value, the biosynthesis of glycyrrhizin has received substantial importance in many parts of the world. The percentage of Glycyrrhizin present in the root as potassium and calcium salts depends on plant species, geographic, and climatic conditions (Sabbioni et al. 2005). It is the flavonoids and chalcones which impart the yellow color to liquorice (Damle 2014). Examples of such flavonoids and chalcones include liquiritin, liquiritigenin, rhamnoliquiritin, neoliquiritin, isoliquiritin, isoliquiritigenin, neoisoliquiritin, licuraside, glabrolide, and licoflavonol (Damle 2014). Structures of important constituents of Glycyrrhiza have been given in Figure 18.1 (Pandey et al. 2017).
Boswellic acids: privileged structures to develop lead compounds for anticancer drug discovery
Published in Expert Opinion on Drug Discovery, 2021
Hidayat Hussain, Iftikhar Ali, Daijie Wang, Faruck L. Hakkim, Bernhard Westermann, Luay Rashan, Ishtiaq Ahmed, Ivan R. Green
Triterpenes having six isoprene units are quite widespread and are found in many natural sources dating from ancient times. It was later determined that these compounds are synthesized via a cascade cyclization of squalene in many plants. Furthermore, over 20,000 triterpenes have been reported from various natural sources and interestingly, most of them are found in their free form while others occur as triterpene glycosides (saponins) [1–4]. Additionally, triterpenes are widespread in various medicinal plants and in particular, in their resin, fruits, leaves, seeds, and bark of the specific herbs. Furthermore, on the basis of the number of isoprene units, triterpenoids can be classified as acyclic, mono-, bi-, tri-, tetra- and pentacyclic. On the other hand, among the triterpenoids, tetracyclic triterpenes (viz., dammaranes, protostanes, euphanes, and cycloartanes) and pentacyclic triterpenes (viz., ursanes, oleananes, gammaceranes, hopanes, and lupanes) are the most studied of the triterpenes [1–4].
The beneficial effects of Ganoderma lucidum on cardiovascular and metabolic disease risk
Published in Pharmaceutical Biology, 2021
Sze Wa Chan, Brian Tomlinson, Paul Chan, Christopher Wai Kei Lam
Terpenes are a large and diverse group of naturally occurring compounds derived from the branched C5 carbon skeleton of isoprene. Triterpenes are a subclass of terpenes and are derived from squalene, a C30 hydrocarbon (Abdullah et al. 2012). They can be classified based on the number of cyclic structures making up the compounds. Up to now, more than 150 triterpenes have been identified from the spores, fruiting bodies, and mycelia of G. lucidum (Xia et al. 2014; Baby et al. 2015). The methods of extraction of triterpenes usually involve methanol, ethanol, chloroform, ether, acetone, or a mixture of these solvents. The extracts can be further purified by various separation methods such as normal and reverse-phase high-performance liquid chromatography (HPLC) (Chen et al. 1999). The majority of triterpenes identified are ganoderic acids and lucidenic acids; other important triterpenes include ganodermic acids, ganoderals, and ganoderiols (Wachtel-Galor et al. 2011). The strong bitterness of G. lucidum originates from the triterpenoid compounds and the bitterness depends on the strain, cultivation conditions and manufacturing processes (Seo et al. 2009). Triterpenoids have been reported to exhibit various biological activities including anti-hypertensive, lipid-lowering, anti-acetylcholinesterase, antioxidant, and anticancer activities, etc. (Abdullah et al. 2012; Chen et al. 2017).
Ursolic acid derivative UA232 evokes apoptosis of lung cancer cells induced by endoplasmic reticulum stress
Published in Pharmaceutical Biology, 2020
Wenfeng Gou, Na Luo, Huiqiang Wei, Hongying Wu, Xiaojun Yu, Yuqing Duan, Changfen Bi, Hongxin Ning, Wenbin Hou, Yiliang Li
About 60% of approved anticancer drugs come from natural resources, so natural products play a leading role in drug discovery (Gupta et al. 2005). Triterpenes have been the focus of drug development because of their good transformation function, biological activity, and ubiquitous characteristics. UA, a pentacyclic triterpenoid acid, is found abundantly in plants, especially in fruit and vegetable (Chang et al. 2017). Although UA plays a variety of biological activities, its poor bioavailability seriously limits its clinical application (Biswas et al. 2019). Structural modification of bioactive natural products has become an important means of developing potential bioactive molecules and leading drugs (Grabley and Sattler 2003). We synthesized a series of compounds by modifying the structure of ursolic acid and found that UA232 has stronger antitumor activity.