Synergized enzyme-ultrasound-assisted aqueous two-phase extraction and antioxidant activity validation of polysaccharides from tobacco waste

A powerful and innovative technique was developed to efficiently extract and refine polysaccharides from tobacco waste. This was achieved through a combination of enzyme and ultrasound-assisted extraction assisted aqueous two-phase extraction (EUAATPE). The formation of an aqueous two-phase system (ATPS) using various salts and ethanol was investigated. ATPS of 18.0 % (NH4)2SO4 (w/w) and 25.0 % ethanol (w/w) was chosen due to its favorable selection extraction ability and high recovery of 93.68 +/- 0.40 %. By utilizing both single-factor experiments and response surface method (RSM), the key factors involved in the EUAATPE process were optimized. The optimal conditions were as follows: ultrasonic power 180 W, ultrasonic time 9 min, cellulase concentration 2.0 %, pectinase concentration 1.0 %, extraction temperature 50 degrees C, extraction time 1.5 h, and liquidto-solid ratio 30:1 (g/g). Under the optimal conditions, the extraction yield of polysaccharides was 6.72 +/- 0.11 (mg/g), and the purity of the polysaccharides from the bottom phase was 78.73 +/- 3.17 %. EUAATPE resulted in a significant enhancement in the extraction yield and purity of polysaccharides from tobacco waste compared to traditional methods such as hot water extraction (HWE), ultrasound-assisted extraction (UAE) and enzymeassisted extraction (EAE). Polysaccharides of tobacco waste obtained from various methods had analogous monosaccharide compositions, different molar ratio compositions and surface structure characteristics. Moreover, all polysaccharides exhibited a certain extent antioxidant activities and polysaccharides from the bottom phase (PBP) extracted by EUAATPE showed superior antioxidant activity. Hence, EUAATPE, being an innovative and eco-friendly extraction technique, presents a productive substitute for extracting and refining polysaccharides from discarded tobacco resources.