Optimization of Roselle (Hibiscus sabdariffa) Anthocyanin Extraction Parameter by Response Surface Modelling and Potential of Stems, Leaves and Calyces Residue as an Alternative Sources of Anthocyanin for Different Industrial Sectors. Nurul Nadiah Abu Bakar (1), Rozida Mohd Khalid (1*), Jalifah Latip (1), Syaifuzah Sapian (2)
1) Department of Chemical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia- nadiahabubakar[at]hotmail.com- jalifah[at]ukm.edu.my
2)Centre for Diagnostic, Therapeutic and Investigative Studies, Faculty of Health Sciences,
Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia- syaifuzahsapian17[at]gmail.com
*Correspondence: rozidakhalid[at]ukm.edu.my
Abstract
Roselle (Hibiscus sabdariffa) is perennial plants found in Malaysia that are rich in anthocyanin content mainly in calyces. However, the different extraction parameters can affect the amount of anthocyanin yielded from roselle. Hence, this study was aimed to optimize the anthocyanin extraction conditions to achieve highest anthocyanin concentration in calyces and apply the optimized conditions in stems, leaves, and calyces residue. For this purpose, optimization was implemented by using Response Surface Methodology (RSM) and Central Composite experimental design. Two variables of ethanol percentage and extraction time were used for optimization and proceeded with a pH differential method to determine the anthocyanin content and quantify the major anthocyanin (delphinidin-3-sambubioside and cyanidin-3-sambubioside) with high performance liquid chromatography (HPLC). Then, optimized conditions were applied to stems, leaves, and calyces residue to compare the anthocyanin content with calyces. The optimization model showed that 70% of ethanol (v/v) with the extraction time 30 minutes yielded highest anthocyanin content of 3.420 mg Cya3G/g DW from calyces. The anthocyanin content in stem, leaves, and calyces residue yielded by using the optimized conditions were about 0.073 mg Cya3G/g DW, 0.072 mg Cya3G/g DW, 2.227 mgCya3G/g DW respectively. Thus, this study suggests that anthocyanin from stem, leaves, and calyces residue can be further isolated for future studies to unveil their potential to be used as alternative sources of anthocyanin.
