Abstract:
Phenolics content of two roselle varieties, H. sabdariffa var. UKMR-2 and H. sabdariffa var. UMKL-1 was determined based on High Performance Liquid Chromatographic method using a photodiode array detector (HPLC-PDA) with gradient elution. Roselle calyces were extracted with water via sonication (50 °C, 30 min). The chromatographic separation was carried out on Purospher STAR RP-18e LichroCART column (250 mm × 4.6 mm × 5 µm) and detection was carried out at three different wavelengths (265, 320 and 520 nm). The developed HPLC method provided high percentage of recovery (95 - 102%), good linearity at R2 > 0.99, low limit of detection (LOD) and low limit of quantitation (LOQ). Two predominant anthocyanins were detected by HPLC-PDA in both H. sabdariffa varieties and were identified as delphinidin-3-O-sambubioside and cyanidin-3-O-sambubioside. In addition, chlorogenic acid, caffeic acid and ascorbic acid were also detected.
