CO2-responsive ionic liquid for the sustainable extraction and separation of Rosa roxburghii polysaccharides.

The extraction of Rosa roxburghii polysaccharides using conventional methods suffers from low extraction efficiency and poor selectivity. Recently, green and efficient methods of polysaccharide extraction have received increasing attention. In this study, a CO2-responsive ionic liquid (IL) was developed for the extraction of Rosa roxburghii polysaccharides. This IL can achieve efficient extraction, and can be recycled, and reused in the extraction process. The maximum polysaccharide extraction yield of the IL was 253 mg/g under optimal single-factor experiment conditions. Three fractionated polysaccharides, RTFP-1, RTFP-2, and RTFP-3, were obtained by further purification, and their preliminary structures were characterized. RTFP-2 and RTFP-3 showed higher antioxidant and hypoglycemic activities than RTFP-1. This IL maintains high extraction efficiency after 5 cycles and reuse. This extraction method based on a CO2-responsive IL provides an efficient and sustainable method for polysaccharide extraction.