Betulin, a Pentacyclic Tri-Terpenoid: An Hour to Rethink the Compound

Abstract

Betulin, a pentacyclic triterpenoid member of lupane family occurs widely in numerous plants. Betulin, unlike most other constituents is easily isolated that it can be utilized for various pharmacological actions. It is interesting to know that betulin can be easily extracted from bark, stem, leaves, flower, roots etc. of the plant. This review summarizes plethora of reliable pharmacological activities like antiinflammatory, anti-ulcer, anti-diabetic, anti-bacterial, anti-microbial, anti-malarial, anti-viral, anti hyperlipidaemic, anti-cancer and anti HIV exhibited by betulin and its derivatives. For this it can be utilized in herbal as well as synthetic pharmaceutical industries because of its promising efficacy and low levels of toxicity. Although betulin possess a wide range of pharmacological activities, there is still lack of awareness of its proper utilization in the field of medicine. So, need of the hour is to refocus on naturally occurring betulin and its derivatives to avoid side effects caused by synthetic compounds utilized in treating various ailments. Therefore, the aim of the present review is to re-explore the potential of betulin, as an alternative to the compounds possessing higher side effects. Keywords: Table1:Represents the physical properties of betulin [1,30,31] Occurrence of Betulin in NatureBetulin has long been explored by research scientist because of the fact that it has anticancer properties [35,36] and its derivative Betulinic acid is favored due to its anti-HIV activity [12,6,37]. As mentioned in Figure 1: betulin has three most prominent positions where chemical modifications can be easily accomplished, namely primary hydroxyl group at position C-28, secondary hydroxyl group at position C-3, and alkene moiety at position C-20.The bio-chemical modifications at positions C-28 of the parent structure of betulin produces betulinic acid [12,27,[38][39][40][41]. The chief source of Betulin is bark of Birch trees, belonging to family Betulaceae the family of flowering plants. Mostly placed in order Fagales, it can also be placed in order Betulales. The subfamilies include Betuloideae genera Betula (birch), Alnus (alder) and Coryloideaegenera Carpinus (hornbeam), Corylus (hazel), Ostrya and Ostryopsis [42][43][44]. Betulin, a pentacyclictriterpenoid is derived from linear hydrocarbon squalene [31]. Triterpenes have three main classes oleane, ursane and lupane triterpenes. Lupane class comprises betulin, betulinic acid, lupeol [6,45]. Triterpenes are used as traditional herbal medicine and the esters of betulin and fatty acids are used in the production of cosmetics and as plasticizers for PVC [31,46] (Table 2). Pharmacological StudiesBetulin, as we all known till now possess vast pharmacological properties including choleritic, antihelmintic, powerful prophylactic, anti-HIV, antimutagene agent, antiviral, antifungal, anti-leukemia, anti-leishmanial, anti-inflammatory, immunomodulator activities. The latest research suggests some of the major pharmacological properties as discu...