Valorisation of black carrot pomace: microwave assisted extraction of bioactive phytoceuticals and antioxidant activity using Box-Behnken design.

The present study compares three methods viz. microwave assisted extraction (MAE), ultrasonic-assisted extraction (UAE) and conventional solvent extraction (CSE) for extraction of phenolic compounds from black carrot pomace (BCP). BCP is the major by-product generated during processing and poses big disposal problem. Box-Behnken design using response surface methodology was employed to investigate and optimize the MAE of phenolics, antioxidant activity and colour density from BCP. The conditions for maximum recovery of polyphenolics were: microwave power (348.07 W), extraction time (9.8 min), solvent-solid ratio (19.3 mL/g) and ethanol concentration (19.8%). Under these conditions, the extract contained total phenolic content of 264.9 ± 10.02 mg gallic acid equivalents (GAE)/100 mL, antioxidant capacity (AOC) of 13.14 ± 1.05 µmol Trolox equivalents (TE)/mL and colour density of 68.63 ± 5.40 units. The total anthocyanin content at optimized condition was 753.40 ± 31.6 mg/L with low % polymeric colour of 7.40 ± 0.42. At optimized conditions, MAE yielded higher colour density (68.63 ± 5.40), polyphenolic content (264.9 ± 10.025 mg GAE/100 mL) and AOC (13.14 ± 1.05 µmol TE/mL) in a short time as compared to UAE and CSE. Overall results clearly indicate that MAE is the best suited method for extraction in comparison to UAE and CSE. The phenolic rich extract can be used as an effective functional ingredient in foods.

Evaluation of enzyme and microwave-assisted conditions on extraction of anthocyanins and total phenolics from black soybean (Glycine max L.) seed coat.

The present study compares three methods viz. microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE) and conventional solvent extraction (CSE) for extraction of polyphenolic compounds from Black Soybean Seed coat (BSSC). Box-Behnken design using response surface methodology (RSM) was employed to investigate and optimize the MAE and EAE for maximum bioactive content, antioxidant activity, colour density and minimum degradation parameters from BSSC. Optimized MAE conditions for BSSC were: microwave power of 569.46 W, extraction time of 262.54 s, solvent to solid ratio of 40:1 and ethanol concentration (59.99). The predicted anthocyanin content was 5021.47 mg/l, close to experimental optimized value of 5094.9 mg/l with minimum values of degradation parameters viz., Polymeric Colour (PC) (0.131 ±â€¯0.01), Browning Index (BI) (0.202 ±â€¯0.02) and Degradation Index (DI) (0.140 ±â€¯0.02). Overall results clearly indicate that MAE is the best suited method for extraction in comparison to EAE and CSE. The phenolic rich extract can be used as an effective functional ingredient in foods.