Optimization by response surface method the extraction and microencapsulation of bioactive compounds from rosehip fruit, seed and waste with natural deep eutectic solvents

In this study, ultrasound assisted extraction with natural deep eutectic solvents and microencapsulation of the extracts obtained by ionic gelation method was optimized by the central composite design of the response surface method. After analyzing dry matter, ash, water activity, pH, color and sugar composition in rosehip samples, for the determination of the best natural deep eutectic solvent total phenolic content, free radical scavenging capacity, vitamin C and phenolic composition analyzes were performed in the extracts obtained with various natural deep eutectic solvents. According to the results of the analysis, after determining the most suitable natural deep eutectic solvent for rosehip samples, the optimization of extraction was carried out using the central composite design method. Temperature, duration and ultrasound power were chosen as independent variables, while total phenolic substance, free radical removal capacity, vitamin C and yield % were chosen as dependent variables. According to the desirability function, optimum values for rosehip fruit, kernel and waste were obtained as 43 °C, 50 °C and 45 °C for temperature, 14 min for all samples and 60%, 53% and 50% for extraction power, respectively. Extracts of each rosehip sample were obtained with the most suitable natural deep eutectic solvent under the optimum conditions. The microencapsulation process was carried out by the ionic gelation method, which has a very high yield and is very suitable for laboratory conditions. Microencapsulation of extracts by ionic gelation method was also optimized by the central composite design of the response surface method. In the microencapsulation process, independent variables were selected as alginate ratio, calcium chloride rate and sample amount, while total phenolic content, free radical scavenging capacity, vitamin C and yield % were chosen as dependent variables. According to the desirability function, optimum points for rosehip fruit, kernel and waste were obtained as 2.45%, 2.5% and 2.5% for the alginate ratio, 2.5% for calcium chloride ratio for all samples, 13, 11.75 and 13 g for sample amount, respectively. In this study, it has been determined that the bioactive compounds of rosehip samples can be extracted efficiently using natural deep eutectic solvent and the negativities that may occur during microencapsulation can be eliminated with natural deep eutectic solvent. Key Words: Rosehip, waste, ionic gelation, natural deep eutectic solvents, optimization, vitamin C, phenolic material, microencapsulation