A new method for the determination of antithrombotic activity of egg white protein hydrolysate （EWPH） was developed using a microplate reader. Reaction was carried out at 37℃and pH 7.2 with fibrinogen concentration...A new method for the determination of antithrombotic activity of egg white protein hydrolysate （EWPH） was developed using a microplate reader. Reaction was carried out at 37℃and pH 7.2 with fibrinogen concentration 0.1%. Microplate reading was conducted at 405 nm. Inhibition rate of EWPH on thrombin activity showed linearity （R2 = 0.9971）, when the inhibition rate was in the range of 10-90%. The lower limit of detection （LLD, at 99.7% probability） and the biological limit of detection （BLD, at 99.7% probability） of the method were 10.643 and 40 mg/mL, respectively. The repeatability standard deviation （R.S.D.） was 1.08%. The standard deviation of the method was ±0.027 AT-U.展开更多
Viral diseases are an important threat to crop yield,as they are responsible for losses greater than US$30 billion annually.Thus,understanding the dynamics of virus propagation within plant cells is essential for devi...Viral diseases are an important threat to crop yield,as they are responsible for losses greater than US$30 billion annually.Thus,understanding the dynamics of virus propagation within plant cells is essential for devising effective control strategies.However,viruses are complex to propagate and quantify.Existing methodologies for viral quantification tend to be expensive and time-consuming.Here,we present a rapid cost-effective approach to quantify viral propagation using an engineered virus expressing a fluorescent reporter.Using a microplate reader,we measured viral protein levels and we validated our findings through comparison by western blot analysis of viral coat protein,the most common approach to quantify viral titer.Our proposed methodology provides a practical and accessible approach to studying virus-host interactions and could contribute to enhancing our understanding of plant virology.展开更多
As the use of Cannabis products as natural medicines burgeons,it is also appearing as a food ingredient.It is important to screen Cannabis samples as ingredients by profiling their chemical compositions,which is refer...As the use of Cannabis products as natural medicines burgeons,it is also appearing as a food ingredient.It is important to screen Cannabis samples as ingredients by profiling their chemical compositions,which is referred to as chemotyping.Two sets of botanical extracts were studied.The first set is referred to as Cannabis contained plant materials from 15 samples of the sativa,indica,and hybrids of the two species.The second set contained 20 extracts from the variety of Cannabis sativa with low tetrahydrocannabinol(THC)concentrations,i.e.,below 0.3%,and,henceforth,will be referred to as hemp.An ultraviolet(UV)microplate reader provides a cost-effective and high-throughput method for identifying chemotypes of plant extracts by their spectra.The microplate reader affords rapid measurements of small volumes,e.g.,50μL,which demonstrates a potential to significantly reduce the analysis time and cost for Cannabis and hemp chemotyping or chemi-cal profiling.Replicate samples were measured on different days to demonstrate the robustness of the method.Projected difference resolution(PDR)maps were used to visualize the separations among the classes.Five multivariate classifiers,fuzzy rule-building expert system(FuRES),super partial least squares-discriminant analysis(sPLS-DA),support vector machine(SVM),and two tree-based support vector machines(SVMtreeG and SVMtreeH)were evaluated.The classifiers were validated with ten bootstrapped Latin partitions(BLPs).For the Cannabis extracts,the SVMtreeG yielded the best performance and the classification accuracy was 99.1±0.4%for spectra collected in the nonlinear absorbance range.For the hemp extracts,the SVM classifier performed the best with a 97.4±0.6%classification accuracy.These results demonstrate that the UV microplate reader coupled with multivariate classifiers can be used as a high-throughput and cost-effective approach for chemotyping Cannabis.展开更多
为了提高植物中γ-氨基丁酸的检测效率和准确性,对用酶标仪测定麦苗中γ-氨基丁酸含量的方法进行了提取方式、反应试剂用量、波长选取和测定时间等参数的优化研究,并对检测结果进行了分析。结果表明,酶标仪测量γ-氨基丁酸的最佳条件为...为了提高植物中γ-氨基丁酸的检测效率和准确性,对用酶标仪测定麦苗中γ-氨基丁酸含量的方法进行了提取方式、反应试剂用量、波长选取和测定时间等参数的优化研究,并对检测结果进行了分析。结果表明,酶标仪测量γ-氨基丁酸的最佳条件为：55℃超声波提取30 min,当待测液为1 m L时,需2 mol·L-1氯化铝0.4 m L,1 mol·L-1氢氧化钾1.0 m L,0.2 mol·L-1p H值10.0的缓冲液1.0 m L,6%重蒸酚1.5 m L,5%次氯酸钠1 m L,最适测量波长为635μm,测定时间为反应后100~160 min。该检测方法稳定性高,重现性好。展开更多
本实验利用3,5-二硝基水杨酸(DNS)比色法对番茄果实总糖含量进行了测定,并初步建立了微型化DNS比色法测定总糖含量的实验方法和DNS比色法测定番茄总糖含量的最佳条件,对影响测定结果的因素:测定波长、显色剂用量、显色时间进行了单因素...本实验利用3,5-二硝基水杨酸(DNS)比色法对番茄果实总糖含量进行了测定,并初步建立了微型化DNS比色法测定总糖含量的实验方法和DNS比色法测定番茄总糖含量的最佳条件,对影响测定结果的因素:测定波长、显色剂用量、显色时间进行了单因素试验。结果表明,540 nm波长、0.2 m L DNS、沸水浴4 min为最佳测定条件。该最佳测定条件下,葡萄糖含量在20~200μg与吸光值呈良好的线性关系。利用得到优化方法对4个番茄品种的总糖含量进行了测定,结果表明测定样品在1.5 h内的吸光值较为稳定,RSD为2.19%~2.88%。本研究得到番茄果实总糖含量测定的优化方法,是一种稳定、高效可行的测定方法,为番茄高糖品种的鉴定和筛选提供了依据。展开更多
文摘A new method for the determination of antithrombotic activity of egg white protein hydrolysate （EWPH） was developed using a microplate reader. Reaction was carried out at 37℃and pH 7.2 with fibrinogen concentration 0.1%. Microplate reading was conducted at 405 nm. Inhibition rate of EWPH on thrombin activity showed linearity （R2 = 0.9971）, when the inhibition rate was in the range of 10-90%. The lower limit of detection （LLD, at 99.7% probability） and the biological limit of detection （BLD, at 99.7% probability） of the method were 10.643 and 40 mg/mL, respectively. The repeatability standard deviation （R.S.D.） was 1.08%. The standard deviation of the method was ±0.027 AT-U.
基金Funding from Natural Sciences and Engineering Research Council of Canada award number RGPIN/4002-2020.
文摘Viral diseases are an important threat to crop yield,as they are responsible for losses greater than US$30 billion annually.Thus,understanding the dynamics of virus propagation within plant cells is essential for devising effective control strategies.However,viruses are complex to propagate and quantify.Existing methodologies for viral quantification tend to be expensive and time-consuming.Here,we present a rapid cost-effective approach to quantify viral propagation using an engineered virus expressing a fluorescent reporter.Using a microplate reader,we measured viral protein levels and we validated our findings through comparison by western blot analysis of viral coat protein,the most common approach to quantify viral titer.Our proposed methodology provides a practical and accessible approach to studying virus-host interactions and could contribute to enhancing our understanding of plant virology.
文摘As the use of Cannabis products as natural medicines burgeons,it is also appearing as a food ingredient.It is important to screen Cannabis samples as ingredients by profiling their chemical compositions,which is referred to as chemotyping.Two sets of botanical extracts were studied.The first set is referred to as Cannabis contained plant materials from 15 samples of the sativa,indica,and hybrids of the two species.The second set contained 20 extracts from the variety of Cannabis sativa with low tetrahydrocannabinol(THC)concentrations,i.e.,below 0.3%,and,henceforth,will be referred to as hemp.An ultraviolet(UV)microplate reader provides a cost-effective and high-throughput method for identifying chemotypes of plant extracts by their spectra.The microplate reader affords rapid measurements of small volumes,e.g.,50μL,which demonstrates a potential to significantly reduce the analysis time and cost for Cannabis and hemp chemotyping or chemi-cal profiling.Replicate samples were measured on different days to demonstrate the robustness of the method.Projected difference resolution(PDR)maps were used to visualize the separations among the classes.Five multivariate classifiers,fuzzy rule-building expert system(FuRES),super partial least squares-discriminant analysis(sPLS-DA),support vector machine(SVM),and two tree-based support vector machines(SVMtreeG and SVMtreeH)were evaluated.The classifiers were validated with ten bootstrapped Latin partitions(BLPs).For the Cannabis extracts,the SVMtreeG yielded the best performance and the classification accuracy was 99.1±0.4%for spectra collected in the nonlinear absorbance range.For the hemp extracts,the SVM classifier performed the best with a 97.4±0.6%classification accuracy.These results demonstrate that the UV microplate reader coupled with multivariate classifiers can be used as a high-throughput and cost-effective approach for chemotyping Cannabis.
文摘为了提高植物中γ-氨基丁酸的检测效率和准确性,对用酶标仪测定麦苗中γ-氨基丁酸含量的方法进行了提取方式、反应试剂用量、波长选取和测定时间等参数的优化研究,并对检测结果进行了分析。结果表明,酶标仪测量γ-氨基丁酸的最佳条件为：55℃超声波提取30 min,当待测液为1 m L时,需2 mol·L-1氯化铝0.4 m L,1 mol·L-1氢氧化钾1.0 m L,0.2 mol·L-1p H值10.0的缓冲液1.0 m L,6%重蒸酚1.5 m L,5%次氯酸钠1 m L,最适测量波长为635μm,测定时间为反应后100~160 min。该检测方法稳定性高,重现性好。
文摘本实验利用3,5-二硝基水杨酸(DNS)比色法对番茄果实总糖含量进行了测定,并初步建立了微型化DNS比色法测定总糖含量的实验方法和DNS比色法测定番茄总糖含量的最佳条件,对影响测定结果的因素:测定波长、显色剂用量、显色时间进行了单因素试验。结果表明,540 nm波长、0.2 m L DNS、沸水浴4 min为最佳测定条件。该最佳测定条件下,葡萄糖含量在20~200μg与吸光值呈良好的线性关系。利用得到优化方法对4个番茄品种的总糖含量进行了测定,结果表明测定样品在1.5 h内的吸光值较为稳定,RSD为2.19%~2.88%。本研究得到番茄果实总糖含量测定的优化方法,是一种稳定、高效可行的测定方法,为番茄高糖品种的鉴定和筛选提供了依据。
