Optimization of Total Anthocyanin Content, Stability and Antioxidant Evaluation of the Anthocyanin Extract from Vietnamese <i>Carissa Carandas</i> L. Fruits

• Main Authors: Xuan Tien Le, Minh Thuan Huynh, Tri Nhut Pham, Van Thai Than, Tran Quoc Toan, Long Giang Bach, Nguyen Quang Trung
• Format: Article
• Language: English
• Published: MDPI AG 2019-07-01
• Series: Processes
• Subjects: anthocyanin; <i>Carissa carandas</i> L.; extract conditions; stability; antioxidant properties
• Online Access: https://www.mdpi.com/2227-9717/7/7/468

In this study, the extraction of anthocyanin colorant from karanda fruit (<i>Carissa</i> <i>carandas</i> L.) was carried out and optimized with multiple single factor assays. Selected conditions for yield maximization consisted of ripen fruits with black-purple color, material size of thin slices (1.0&#8722;1.5 mm), solvent of EtOH 50%, material/ solvent ratio of 1:3, temperature of 50 &#176;C, extraction time of 45 min, and two extraction cycles. The anthocyanin content in the extract was 277.2 mg/L, which is equivalent to 9.33 mg anthocyanin per gram of dry material. Aqueous solutions of the extract and dried extracts from <i>Carissa</i> <i>carandas</i> fruit were evaluated for stability at two temperature conditions, namely room temperature (30 &#177; 2 &#176;C) and 45 &#176;C. The temperature exerted great impact on color change, anthocyanin content and the degree of polymerization of anthocyanin. Aqueous solutions of extract with citric acid (3.0&#8722;5.0 g/L) were generally more color stable and less anthocyanin degradable than those without citric acid. In the DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging assay, The half maximal inhibitory concentration (IC₅₀) of the dried extract was 87.56 &#956;g/mL, which was approximately 29 times higher than that of vitamin C. After 3-month storage at &#8722;18 &#176;C, IC₅₀ of the dried extract was 173.67 &#956;g/mL.