Objective:To develop and validate an image analysis method for quantitative analysis ofγ-oryzanol in cold pressed rice bran oil.Methods:TLC-densitometric and TLC-image analysis methods were developed,validated,and us...Objective:To develop and validate an image analysis method for quantitative analysis ofγ-oryzanol in cold pressed rice bran oil.Methods:TLC-densitometric and TLC-image analysis methods were developed,validated,and used for quantitative analysis of γ-oryzanol in cold pressed rice bran oil.The results obtained by these two different quantification methods were compared by paired t-test.Results:Both assays provided good linearity,accuracy,reproducibility and selectivity for determination of γ-oryzanol.Conclusions:The TLC-densitomelric and TLC-image analysis methods providett a similar reproducibility,accuracy and selectivity for the quantitative determination of γ-oryzanol in cold pressed rice bran oil.A statistical comparison of the quantitative determinations of γ-oryzanol in samples did not show any statistically significant difference between TLC-densitometric and TLC-image analysis methods.As both methods were found to be equal,they therefore can be used for the determination of γ-oryzanol in cold pressed rice bran oil.展开更多
为了揭示亚临界流体萃取米糠油及其微量活性组分的动力学规律,该文以亚临界丙烷为萃取介质,研究了米糠油、γ-谷维素及α-生育酚等活性组分在不同萃取温度和时间的萃取率,并基于Baümler模型对目标物的萃取率进行模型拟合,建立相应...为了揭示亚临界流体萃取米糠油及其微量活性组分的动力学规律,该文以亚临界丙烷为萃取介质,研究了米糠油、γ-谷维素及α-生育酚等活性组分在不同萃取温度和时间的萃取率,并基于Baümler模型对目标物的萃取率进行模型拟合,建立相应的动力学模型并验证。结果表明,亚临界萃取过程中目标物的相对萃取率随时间增长递增,且在初始阶段(洗涤过程)的增长速率快于第二阶段(扩散过程)的增长速率;同时,升高萃取温度可同时提高目标产物的扩散系数和相对萃取率;基于Baümler模型可较好拟合亚临界丙烷萃取米糠油、γ-谷维素和α-生育酚的动力学过程(R2>0.95),所得动力学模型具有较好的预测准确性。由Arrhenius方程可计算出米糠油、α-生育酚和γ-谷维素的亚临界萃取反应活化能,其中米糠油的活化能最低(5.23 k J/mol),α-生育酚次之(7.05 k J/mol),γ-谷维素最高(9.11 k J/mol),表明γ-谷维素最难萃取且对温度依赖程度最高;根据拟合所得动力学模型,对米糠油提取率进行预测,结果表明,该模型对米糠油萃取率的预测准确率达95.8%,而对γ-谷维素和α-生育酚萃取率的预测准确度稍低,分别达94.7%和94.4%,对三者均具有很好的预测准确性。总之,基于Baümler模型可以较好地建立米糠油及其有益伴随物的亚临界萃取动力学模型,从而较为准确的预测米糠油及其微量活性组分的萃取率,对米糠油的亚临界萃取工艺具有一定的理论指导意义。展开更多
基金Supported by the Research Institute of Rangsit University,Pathum Thani,Thailand(Grant No.73/55)
文摘Objective:To develop and validate an image analysis method for quantitative analysis ofγ-oryzanol in cold pressed rice bran oil.Methods:TLC-densitometric and TLC-image analysis methods were developed,validated,and used for quantitative analysis of γ-oryzanol in cold pressed rice bran oil.The results obtained by these two different quantification methods were compared by paired t-test.Results:Both assays provided good linearity,accuracy,reproducibility and selectivity for determination of γ-oryzanol.Conclusions:The TLC-densitomelric and TLC-image analysis methods providett a similar reproducibility,accuracy and selectivity for the quantitative determination of γ-oryzanol in cold pressed rice bran oil.A statistical comparison of the quantitative determinations of γ-oryzanol in samples did not show any statistically significant difference between TLC-densitometric and TLC-image analysis methods.As both methods were found to be equal,they therefore can be used for the determination of γ-oryzanol in cold pressed rice bran oil.
文摘为了揭示亚临界流体萃取米糠油及其微量活性组分的动力学规律,该文以亚临界丙烷为萃取介质,研究了米糠油、γ-谷维素及α-生育酚等活性组分在不同萃取温度和时间的萃取率,并基于Baümler模型对目标物的萃取率进行模型拟合,建立相应的动力学模型并验证。结果表明,亚临界萃取过程中目标物的相对萃取率随时间增长递增,且在初始阶段(洗涤过程)的增长速率快于第二阶段(扩散过程)的增长速率;同时,升高萃取温度可同时提高目标产物的扩散系数和相对萃取率;基于Baümler模型可较好拟合亚临界丙烷萃取米糠油、γ-谷维素和α-生育酚的动力学过程(R2>0.95),所得动力学模型具有较好的预测准确性。由Arrhenius方程可计算出米糠油、α-生育酚和γ-谷维素的亚临界萃取反应活化能,其中米糠油的活化能最低(5.23 k J/mol),α-生育酚次之(7.05 k J/mol),γ-谷维素最高(9.11 k J/mol),表明γ-谷维素最难萃取且对温度依赖程度最高;根据拟合所得动力学模型,对米糠油提取率进行预测,结果表明,该模型对米糠油萃取率的预测准确率达95.8%,而对γ-谷维素和α-生育酚萃取率的预测准确度稍低,分别达94.7%和94.4%,对三者均具有很好的预测准确性。总之,基于Baümler模型可以较好地建立米糠油及其有益伴随物的亚临界萃取动力学模型,从而较为准确的预测米糠油及其微量活性组分的萃取率,对米糠油的亚临界萃取工艺具有一定的理论指导意义。
