Potential sources of anti-obesity compound – hydroxycitric acid among some of the underutilized fruits in the Philippines

Abstract

Hydroxycitric acid (HCA), a derivative of citric acid, is one of the promising food components with reported anti-obesity properties. HCA is currently extracted only from its principal source, Garcinia cambogia, which is not readily available in the country. Herewith, the study aims to identify potential sources of HCA among local underutilized fruits to increase their current commercial use. A total of twenty underutilized fruits generally rich in citric acid were screened via histochemical staining to detect the presence of HCA. Those samples that produced the characteristic reddish orange colour complexes indicative of HCA have undergone further experiments including extraction (via water extraction method), quantification (via spectrophotometry), and identity validation (via thin layer chromatography) to determine the actual HCA sources. Out of the 20 local fruits tested, HCA was found only from Tamarindus indica L. (tamarind) flesh at 3.731±0.046 g HCA/100 g fresh weight and from Garcinia binucao (batuan) flesh and seeds at 3.447±0.059 g HCA/100 g fresh weight and 1.241±0.009 g HCA/100 g fresh weight, respectively. Meanwhile, most of the other fruits tested were found to contain merely citric acid. This study could bring new ways in utilizing batuan and tamarind fruits as functional ingredients in nutraceuticals and value-added products, thereby increasing its current health and economic significance.