ABSTRACT
OBJECTIVE：To compare the methods for the con tent determination of polysaccharide and reducing sugar in Polygonatum cyrtonema， and to optimize the wine-steaming technology of P. cyrtonema . METHODS ： The contents of polysaccharide in P. cyrtonema were determined by anthrone-sulfuric acid method and phenol-sulfuric acid method. The contents of reducing sugar in P. cyrtonema were determined by anthrone-sulfuric acid method ， phenol-sulfuric acid method and 3， 5-dinitrosalicylic acid （DNS）method，respectively. Taking appearance and property scores of processed products ，the contents of polysaccharide，reducing sugar and total sugar as indicators ，the amount of alcohol added ，steaming time and moistening time as factors，the wine-steaming technology of P. cyrtonema was optimized by Latin square design. The contents of polysaccharide ， reducing sugar and total sugar were compared before and after steaming. RESULTS ：The linear ranges of polysaccharide and reducing sugar obtained by anthrone-sulfuric acid method were both 0.006 6-0.033 mg/mL（R2＝0.999 9）. RSDs of precision ， stability（90 min）and reproducibility tests were all lower than 3％ and 2％，respectively. Average recoveries were 99.75％（RSD＝ 0.48％，n＝6）and 103.40％（RSD＝1.25％，n＝6），respectively. The linear ranges of polysaccharide and reducing sugar obtained by phenol-sulfuric acid method were both 0.002 5-0.025 mg/mL（R2＝0.999 2）. RSDs of precision ，stability （90 min） and reproducibility tests were all lower than 5％ and 6％，respectively. Average recoveries were 112.80％（RSD＝2.36％，n＝6）and 99.20％（RSD＝3.47％，n＝6）. The linear range of reducing sugar obtained by DNS method was 0.01-0.18 mg/mL（R2＝0.999 9）. RSDs of precision ，stability（90 min）and reproducibility tests were all lower than 2％. Average recoveries was 96.95％（RSD＝ 1.19％，n＝6）. The optimal wine-steaming technology of P. cyrtonema included the amount of alcohol added of 20％，moistening time of 2 h and steaming time of 7 h. RSDs of average contents of polysaccharide ，reducing sugar and total sugar in wine-steamed products were all lower than 3％ in 3 times of validation tests （n＝3）. The average contents of polysaccharide ，reducing sugar and total sugar in 4 batches of P. cyrtonema were 16.3％，11.2％ and 27.4％；those of 4 batches of wine-steamed products were 3.4％， 61.0％ and 64.4％，respectively. CONCLUSIONS ：The anthrone- ） sulfuric acid method is the best for the determination of poly- saccharide in P. cyrtonema ；DNS method is the best for the pandongmei1228@126.com determination of reducing sugar in P. cyrtonema. The content ofpolysaccharide in wine-steamed products is decreased signifi- cantly，while the contents of reducing sugar and total sugar are increased significantly.