Recent studies on betulinic acid and its biological and pharmacological activity

Betulinic acid (3β-hydroxy-lup-20(29)-en-28-oic acid, BA), a pentacyclic lupane-type triterpene, is widely distributed in the plant kingdom (Mukherjee et al., 2006; Fulda, 2008). Johann Tobias Lowitz isolated the reduced form of BA from plants in 1788 and found that it was a prominent outer-bark constituent in white-barked birch trees (Bag and Dash, 2011). BA has a wide range of biological and medicinal properties, including anti-human immunodefi-ciency virus (HIV), antibacterial, antimalarial, anti-inflammatory, anthelmintic, antinocicep-tive, anti-herpes simplex viruses-1 (HSV-1), immune-modulatory, antiangiogenic, and anti-cancer activity (Yogeeswari and Sriram, 2005; Gheorgheosu et al, 2014). Furthermore, the an-ti-tumor activity of BA can help overcome resistance by inducing apoptosis in a variety of human cancers. Semi-synthetic derivatives of natural plant products continue to play an important role in drug discovery and development (Pan et al., 2010). To improve the potency of BA, many derivatives have been synthesized and evaluated for biological/medicinal applications (Jonnala-gadda et al., 2013; Csuk, 2014). Because of its range of biological properties, BA has attracted much attention in recent years in the pharmaceutical industry. Here, we summarize key recent studies performed to evaluate the biological and pharmacological activities of BA and its derivatives (Table 1).