不同溶剂浸提下核桃果实不同部位多酚物质响应及其组成

Polyphenols Response and Composition of Walnut Fruit at Different Parts Under Different Solvents Immersion

研究不同溶剂浸提核桃分心木及核桃壳多酚物质含量变化及组成,为核桃副产物利用提供技术支撑.基于超声效应辅以不同溶剂浸提解析核桃分心木和核桃壳中多酚含量变化规律;其次通过HPLC(high performance liquid chromatography)鉴定分心木及壳中多酚物质组成,而后通过SEM(scanning electron microscope)观察分心木及壳的微观结构.通过多元二次回归方程模型优化出分心木和核桃壳多酚提取较佳条件为:料液比1∶59(g·mL^(-1))、处理时间31 min、甲醇浓度67%(V/V)、处理温度61℃、超声功率250 W,甲醇浸提分心木多酚得率为(72.7±1.57)mg·g^(-1),建立的多元二次回归方程为Y=71.12-0.079X_(1)+0.36X_(2)-0.13X_(3)+0.40X_(4)-0.91X_(1)X_(2)-0.17X_(1)X_(3)-0.31X_(1)X_(4)-0.45X_(2)X_(3)+0.23X_(2)X_(4)-0.60X_(3)X_(4)-2.10X_(1)^(2)-1.42X_(2)^(2)-0.68X_(3)^(2)-1.35X_(4)^(2);料液比1∶85(g·mL^(-1))、处理时间29 min、处理温度61℃、超声功率250 W,水浸提分心木多酚得率(58.06±1.62)mg·g^(-1),得到的回归方程为Y=53.96+2.19X_(1)-2.31X_(2)+1.25X_(4)-1.08X_(1)X_(2)+0.66X_(1)X_(4)-0.62X_(2)X_(4)-2.68X_(1)^(2)-5.76X_(2)^(2)-2.91X_(4)^(2);料液比1∶60(g·mL)、处理时间31 min、甲醇浓度67%(V/V)、处理温度61℃、超声功率300 W,甲醇浸提核桃壳多酚得率为(20.04±1.32)mg·g^(-1),得到的回归方程为Y=19.58+0.047X_(1)+0.35X_(2)-0.096X_(3)+0.55X_(4)-0.42X_(1)X_(2)-0.39X_(1)X_(3)+0.038X_(1)X_(4)-0.52X_(2)X_(3)+0.27X_(2)X_(4)-0.35X_(3)X_(4)-1.74X_(1)^(2)-1.28X_(2)^(2)-0.59X_(3)^(2)-1.21X_(4)^(2);料液比1∶90(g·mL^(-1))、处理时间37 min、处理温度55℃、超声功率250 W,水浸提核桃壳多酚得率达(15.43±1.18)mg·g^(-1),建立的回归方程为Y=13.77+0.45X_(1)-2.18X_(2)+0.36X_(4)-1.08X_(1)X_(2)-0.42X_(1)X_(4)+0.13X_(2)X_(4)-0.29X_(1)^(2)-3.20X_(2)^(2)+0.22X_(4)^(2).HPLC从分心木中鉴定出2种共有单体酚:没食子酸和儿茶素,没食子酸在水浸提下含量较高,儿茶素在甲醇浸提下含量较高;核桃壳中也鉴定出2种共有单体酚:没食子酸和香草酸,水浸提下没食子酸含量高于甲醇浸提,而香草酸含量在甲醇和水浸提下相差不大;分心木中多酚得率明显高于核桃壳,甲醇水溶液提取效果明显优于纯水浸提;超声效应能够显著破坏分心木和核桃壳表面组织结构,促使多酚更多、更快地释放出来,进入浸提溶剂.

Studying the change polyphenols content of walnut diaphragma juglandis fructus and walnut shell to provide technical support for the utilization of walnut by-products.Analyzing the change and composition of polyphenols different parts of walnut fruit based on ultrasound effect by different solvent extraction.Secondly,the composition of polyphenols was identified by HPLC,and then the microstructure was observed by SEM.Walnut diaphragma juglandis fructus and shell polyphenols extraction conditions were optimized by Multivariate Quadratic Regression Equation Model.The better extraction conditions were as follows:solid to liquid ratio 1∶59(g·mL^(-1)),treatment time 31 min,methanol concentration67%,treatment temperature 61℃,ultrasound power 250 W.At this time,under methanol extraction the polyphenol yield of diaphragma juglandis fructus was(72.7±1.57)mg·g^(-1).The regression equation was established:Y=71.12-0.079X_(1)+0.36X_(2)-0.13X_(3)+0.40X_(4)-0.91X_(1)X_(2)-0.17X_(1)X_(3)-0.31X_(1)X_(4)-0.45X_(2)X_(3)+0.23X_(2)X_(4)-0.60X_(3)X_(4)-2.10X_(1)^(2)-1.42X_(2)^(2)-0.68X_(3)^(2)-1.35X_(4)^(2);solid to liquid ratio 1∶85(g·mL^(-1)),treatment time 29 min,treatment temperature 61℃,ultrasound power 250 W.At this time,under water extraction polyphenol yield of diaphragma juglandis fructus was(58.06±1.62)mg·g^(-1).The regression equation was established:Y=53.96+2.19X_(1)-2.31X_(2)+1.25X_(4)-1.08X_(1)X_(2)+0.66X_(1)X_(4)-0.62X_(2)X_(4)-2.68X_(1)^(2)-5.76X_(2)^(2)-2.91X_(4)^(2).Solid to liquid ratio 1∶60(g·mL^(-1)),treatment time 31 min,methanol concentration 67%,treatment temperature 61℃,ultrasound power 300 W.At this time,under methanol extraction polyphenol yield of walnut shell was(20.04±1.32)mg·g^(-1).The regression equation was established:Y=19.58+0.047X_(1)+0.35X_(2)-0.096X_(3)+0.55X_(4)-0.42X_(1)X_(2)-0.39X_(1)X_(3)+0.038X_(1)X_(4)-0.52X_(2)X_(3)+0.27X_(2)X_(4)-0.35X_(3)X_(4)-1.74X_(1)^(2)-1.28X_(2)^(2)-0.59X_(3)^(2)-1.21X_(4)^(2);solid to liquid ratio 1∶90(g·mL^(-1)),treatment time 37min,treatment temperature 55℃,ultrasound power 250 W.At this time,under water extraction polyphenol yield of walnut shell was(15.43±1.18)mg·g^(-1).The regression equation was established:Y=13.77+0.45X_(1)-2.18X_(2)+0.36X_(4)-1.08X_(1)X_(2)-0.42X_(1)X_(4)+0.13X_(2)X_(4)-0.29X_(1)^(2)-3.20X_(2)^(2)+0.22X_(4)^(2).Through the HPLC analysis,under methanol and water extraction,two common kinds of monophenol identified in diaphragma juglandis fructus were gallic acid and catechin,gallic acid content was higher in water extraction and catechin content was higher in methanol extraction.Two common kinds of monophenol identified in the walnut shell were gallic acid and vanillic acid,gallic acid content was higher than methanol extraction,while the vanillic acid content is not much different between methanol and water extraction.The polyphenol yield was significantly higher in diaphragma juglandis fructus than walnut shell,the extraction effect of methanol solution is significantly better than that of pure water extraction.Scanning electron microscope of the surface of diaphragma juglandis fructus and walnut shell proved that ultrasound effect can significantly damage the surface tissue structures of diaphragma juglandis fructus and walnut shell,to promote the polyphenols to release more and faster,and dissolve into the extraction solution.