东北地区栽培大豆品种籽粒异黄酮含量分析及不同测定方法优化比较

Analysis of Isoflavone Content in Cultivated Soybeans[Glycine max(L.)Merr.] in Northeast China and Comparison of Different Determination Methods

利用超声波技术,以大豆异黄酮主要组分染料木素为对照,根据单因素试验和正交试验结果建立三波长比色法和紫外分光光度法,确定大豆异黄酮最佳提取工艺:乙醇浓度70%,料液比1∶25,提取温度50℃,提取时间5 h,提取2次。比较新建立方法与之前建立HPLC法的精密度和准确度,结果依次为:高效液相色谱法>三波长比色法>紫外分光光度法,其中HPLC法灵敏度高,适于大豆及其制品中异黄酮含量的精确测定,三波长比色法和紫外分光光度法适于异黄酮含量批量、快速测定。采用HPLC法测得东北地区品种异黄酮含量分布范围为1.0404～4.4344μg.mg-1,平均值2.9174μg.mg-1,不同地区大豆品种异黄酮总量分布规律为:黑龙江>吉林>其它地区(主要是辽宁省和内蒙古东部地区),筛选得到大于4.0μg.mg-1高异黄酮品种12份,小于1.0μg.mg-1的低异黄酮品种3份。

Two different soybean isoflavone determination methods including three-wave length UV spectrohometry（TL-UV）and ultraviolet spectrophotometry（UV）were established.The two methods and high-performance liquid chromatographic method（HPLC）established before were optimized and used to measure 128 soybean varieties from northeast China.Single factor experiment and orthogonal experiment were designed to optimize extracted method of soybean isoflavone as determination by TL-UV and UV using ultrasonic wave.The most suitable condition was extracting soybeans with 70% edible ethanol under the 1∶25 ratio of defatted soybean meal to solvent at 50℃ for 5 h,extracting 2 times.Accuracy and precision of the three methods in a descending order was HPLC,TL-UV,UV.HPLC had high analytic sensitivity and accuracy,and was suitable for determination of isoflavone in soybean and other cereal products.The other two methods were suitable for rapid determination and accurate analysis of isoflavones.The isoflavone content of 128 soybean varieties ranged from 1.0404 to 4.4344 μg·mg-1,and the average content was 2.9174 μg·mg-1.The order of soybean isoflavone content among regions was HeilongjiangJilinother region.Twelve varieties with high-soybean isoflavone exceeded 4.0 μg·mg-1 and 3 varieties with low-soybean isoflavone being inferior to 1.0 μg·mg-1were screened.