optimization of microwave-assisted extraction of betalains from red beet (beta vulgaris) and evaluating the antioxidant activity of obtained extract

abstractbackground and objective: microwave assisted extraction (mae) is one of the novel fast and efficient methods for extraction of bioactive compounds. the aim of this study was optimization of mae of betalains from red beet (beta vulgaris) and evaluating antioxidant activity of its methanolic extract.materials and methods: the effects of independent variables namely microwave power level (100 300 w) extraction time (1 15 min) and liquid to solid ratio (10 30 ml/g) were investigated on total extraction yield free radical scavenging activity phenolics flavonoids and betalains (betaxanthin and betacyanin) contents using central composite design.results: according to obtained results the total phenolic flavonoid and betalains contents were significantly decreased by increasing extraction time. simultaneous increase of microwave power level and liquid to solid ratio resulted in significant increase of total phenolic flavonoid and betalains contents (p0.05). the optimized condition of mae of phenolics flavonoids and betalains was microwave power level of 300 w liquid to solid ratio of 30 ml/g and extraction time of 1 min. in contrast simultaneous increase of microwave power level and liquid to solid ratio resulted in significant decrease of total extraction yield (p0.05). the optimized condition of the highest total extraction yield was microwave power level of 100 w liquid to solid ratio of 10 ml/g and extraction time of 15 min.conclusion: we can apply mae method for extraction of bioactive compounds at shorter extraction time and energy saving. abstractbackground and objective: microwave assisted extraction (mae) is one of the novel fast and efficient methods for extraction of bioactive compounds. the aim of this study was optimization of mae of betalains from red beet (beta vulgaris) and evaluating antioxidant activity of its methanolic extract.materials and methods: the effects of independent variables namely microwave power level (100 300 w) extraction time (1 15 min) and liquid to solid ratio (10 30 ml/g) were investigated on total extraction yield free radical scavenging activity phenolics flavonoids and betalains (betaxanthin and betacyanin) contents using central composite design.results: according to obtained results the total phenolic flavonoid and betalains contents were significantly decreased by increasing extraction time. simultaneous increase of microwave power level and liquid to solid ratio resulted in significant increase of total phenolic flavonoid and betalains contents (p0.05). the optimized condition of mae of phenolics flavonoids and betalains was microwave power level of 300 w liquid to solid ratio of 30 ml/g and extraction time of 1 min. in contrast simultaneous increase of microwave power level and liquid to solid ratio resulted in significant decrease of total extraction yield (p0.05). the optimized condition of the highest total extraction yield was microwave power level of 100 w liquid to solid ratio of 10 ml/g and extraction time of 15 min.conclusion: we can apply mae method for extraction of bioactive compounds at shorter extraction time and energy saving.