Publications

Publications serve as the concrete art form for the scientist. It is his modus operandi. Authorship is akin to success and achievement. It cannot and should not deteriorate into a bargaining tool or commodity. Dardik
Badoni Semwal, R., Semwal, D.K., Vermaak, I., Viljoen, A. 2015. A comprehensive scientific overview of Garcina cambogia. Fitoterapia 102: 134-148.
The fruit rind of Garcinia gummi-gutta, commonly known as Garcinia cambogia (syn.), is extensively used traditionally as a flavourant in fish curries due to its sharp sour taste. Additional ethnobotanical uses include its use as a digestive and a traditional remedy to treat bowel complaints, intestinal parasites and rheumatism. This small fruit, reminiscent of a pumpkin in appearance, is currently most popularly used and widely advertised as a weight-loss supplement. Studies have shown that the extracts as well as (–)-hydroxycitric acid (HCA), a main organic acid component of the fruit rind, exhibited anti-obesity activity including reduced food intake and body fat gain by regulating the serotonin levels related to satiety, increased fat oxidation and decreased de novo lipogenesis. HCA is a potent inhibitor of adenosine triphosphate-citrate lyase, a catalyst for the conversion process of citrate to acetyl-coenzyme A, which plays a key role in fatty acid, cholesterol and triglycerides syntheses. The crude extract or constituents from the plant also exerted hypolipidaemic, antidiabetic, anti-inflammatory, anticancer, anthelmintic, anticholinesterase and hepatoprotective activities in in vitro and in vivo models. Phytochemical studies of various plant parts revealed the presence of mainly xanthones (e.g. carbogiol) and benzophenones (e.g. garcinol) together with organic acids (e.g. HCA) and amino acids (e.g. gamma aminobutyric acid). Currently, a large number of G. cambogia/HCA dietary supplements for weight management are being sold although the possible toxicity associated with the regular use of these supplements has raised concerns. In most cases, complaints have been related to multicomponent formulations and at this stage G. cambogia has not been confirmed as the potentially toxic culprit. This review presents a scientific overview of G. cambogia with reference to relevant botanical aspects, ethnobotanical uses, phytochemistry and biological activity as well as toxicity. Butein (2′,3,4,4′-tetrahydroxychalcone), a simple chalcone derivative, occurs in many unrelated genera including Butea, Dahlia, Coreopsis and Searsia.It is a reputed food additive and a common ingredient of botanicals used in herbal medicine formulations, particularly in Asian countries. Although a simple polyphenol, this molecule exhibits a range of pharmacological properties, most notably acting as a potent protein tyrosine kinase inhibitor and as an antineoplastic agent. Researchers have convincingly demonstrated that butein inhibits the epidermal growth factor receptor in HepG2 cells and the tyrosine-specific protein kinase activities of the epidermal growth factor receptor. In addition, it also exhibits promising anti-inflammatory, antidiabetic, antinephritic, antithrombin, anti-angiogenic and hepatoprotective activities in various animal models. Although this molecule is endowed with an impressive list of biological properties, which have acted as scientific support for its commercialization, there are no review articles that coherently discuss various aspects of this chalcanoid. This review aims to explore the pharmacological relevance of butein, together with its structure-activity relationships and mechanisms of action. In addition, the occurrence, chemical synthesis and biosynthesis of butein are discussed.