Optimum conditions of microwave-assisted extraction for phenolic compounds and antioxidant capacity of the brown alga Sargassum vestitum

ABSTRACT

This study aimed to optimise microwave-assisted extraction (MAE) conditions for total phenolic compounds (TPCs) and antioxidant activities of the alga Sargassum vestitum by using response surface methodology with Box–Behnken design. The results showed that solvent concentration had the greatest impact on TPC and antioxidant activities of the extracts, followed by radiation time and power. The optimal MAE conditions were ethanol concentration of 70%, radiation time of 75 s and power of 80%. The optimal MAE method showed much better extraction efficacy of phenolics and antioxidant capacities of the extract than conventional and ultrasonic methods.

KEYWORDS:

• Sargassum vestitum
• brown algae
• microwave-assisted extraction (MAE)
• optimisation
• RSM

Acknowledgments

The authors kindly thank the University of Newcastle, the Vietnamese Government through the Vietnam International Education Development – Ministry of Education and Training and the Ministry of Agriculture and Rural Development for awarding a VIED-TUIT scholarship to ThanhTrung DANG.

Declaration of interest

The authors declare no conflict of interest.

Additional information

Funding

The authors would like to acknowledge the following funding support: Ramaciotti Foundation [ES2012/0104].