Optimization of ultrasound extraction of functional compound from makiang seed by response surface methodology and antimicrobial activity of optimized extract with its application in orange juice

An ultrasound-assisted extraction (UAE) was optimized for the extraction of bioactive compound (total phenolic compound and total flavonoid content) with antioxidant activity (DPPH and FRAP assays) using response surface methodology based on Box-Behnken design (BBD). The effect of extraction temperature (X-1: 30-70 ?), extraction time (X-2: 25-45 min) and amplitude (X-3: 30-50%) were determined. In addition, antimicrobial activity and application of optimized makiang seed extract (MSE) were also evaluated. Results showed that the optimum condition of UAE were X1: 51.82 ?, X-2: 31.87 min and X3: 40.51%. It was also found that gallic acid was the major phenolic compound of optimized MSE and its minimum inhibitiory concentration (MIC) and minimum bactericidal concentration (MBC) was between 1.56 -6.25 and 25-100 mg/mL respectively. The addition of MSE could enhance the stability of orange juice and shelf life extension was also obtained. This research finding suggests the beneficial opportunities for ultrasound-assisted extraction for the production of bioactive compound from makiang seed with antioxidant activity leading to an application in medicinal and functional food industry.

Automated summary

This study optimized the conditions for ultrasound-assisted extraction of bioactive compounds with antioxidant activity from makiang seeds using response surface methodology. The antimicrobial activity and application potential of the optimized extract were also evaluated. The results showed that the optimized extraction conditions were a temperature of 51.82℃, an extraction time of 31.87 minutes, and an amplitude of 40.51%. Gallic acid was identified as the major phenolic compound in the optimized extract, which exhibited low minimum inhibitory and bactericidal concentrations. Additionally, the addition of the optimized extract improved the stability and extended the shelf life of orange juice.