Separation And Purification Of Flavonoids From The Mixed Juice Scum From Sugarcane Mill

The mixed juice scum is. a product of the floatation of mixed juice insugarcane mill, which accounts for 1%～2% of the production quantities andcontains rich organic non-sugar such as protein, lipid, polysaccharides and so on.And its treatment is a problem that must be solved in the industrial applicationof sugar industry. In order to make and choose a better technique route of themulti-purpose utilization of the mixed juice scum, the elementary components ofthe mixed juice scum are determined according to the national standards in thispaper. It contains ash 7.30%, protein 17.02%, crude fat 7.00%, crude fiber11.23% and carbohydrate 68.67%. As the results showed, the mixed juice scumhas high nutritive value and is suitable for utilization, which can alleviate thenegative effect of organic non-sugar in sugar industrial process and reduce theexcretion of filtrated mud coming from sugar industrial process and theenvironmental pollution.The comprehensive utilization level of by-products from sugarcane mill in china is lower than in other countries. Extraction and separation of flavonids inthe mixed juice scum and its anti-oxidative capability were discussed in thisthesis, which to develop a new way for the utilization of cane-sugar by-productand to provide raw materials of additives for functional food and medical &pharmaceutical industries. The main research contents and results of this thesisare as follows:1. The separation of the alcohol soluble substance in the mixed juice scumand its scavenging ability to DPPH·were discussed. The alcohol solublesubstance was separated by soxhlet extraction and its anti-oxidative capabilitywas determined rapidly by DPPH·method in this paper. Based on quadraticregression orthogonal design, the relational expression between extractiontime, liquid/solid ratio and the antioxidant value of extract was obtained.Influencing factors of extraction were optimized by response surface analysis.2. The extraction conditions of total flavonoids from the mixed juice scumwere studied. The flavonids in the mixed juice scum were extracted by differentextraction conditions based on the orthogonal experiments design. Rutin wasused as a standard compound and flavonoids content of the mixed juice scumwas quantified by measuring the absorbance at 510 nm by spectrometric method.The results indicated the optimum extracting condition of ultrasonic intensifiedethanol extraction method being A₂B₂C₃D₂, i.e., 60% ethanol as solvent, ratioof liquid/solid as 1: 50, temperature of extraction at 80℃and extracting time of60min.3. Semlpreparation high-speed countercurret chromatography(HSCCC) was used for the systematic optimization and preparation of the two-phase solventsystem to separate flavonoids in the mixed juice scum. The two-phase solventsystem composed of n-hexane/ethyl acetate/methanol/water (1: 0.6: 0.6: 1 involume ratio). The mobile phase is the lower phase and operated at flow-rate of2.0 mL/min, while the apparatus rotated at 800r/min. High performance liquidchromatographic analysis of flavonoids revealed that its purity was 90.6%.