Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information...Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information of free amino acids in food, we have carried out the experiments to quantitate the free amino acids by derivatized with NBD-F (4-fluoro-7-nitrobenzofurazan) and analyzed on reversed-phase UHPLC (ultra-high pressure liquid chromatography) equipped with ultraviolet visible detector. Almost all of food extracts contained free amino acids including GABA (T-amino butyrate). Contents of free amino acids vary considerably depending upon vegetables and fruits. Principal free amino acids found in vegetables and fruits were asparagine, glutamine, arginine and GABA, which are involved in important metabolic pathways in human. About 140 species of vegetables and fruits were subjected for the data base. All of the plants and fruits we examined exhibit significant amount of free amino acids, those are clearly distinct from data bases obtained after acid hydrolysis treated food samples. Since glutamate and GABA act as excitatory and inhibitory neurotransmitters in CNS, respectively; free amino acids in vegetables and fruits that we eat daily, should be an important source for the cellular metabolic activities.展开更多
Time dependent carbon transfer coefficients are estimated using ecosystem exchange databy minimizing over variable observational intervals,Kalman filter,and variational minimization techniques.Transfer coefficients ar...Time dependent carbon transfer coefficients are estimated using ecosystem exchange databy minimizing over variable observational intervals,Kalman filter,and variational minimization techniques.Transfer coefficients are determined by application of estimation procedures to subintervalsfrom a partition of the observational time period,minimizing the variance of analyzed errors withoutthe imposition of a priori transfer coefficient models in Kalman filters,and minimization with respectto transfer coefficients in variational fit-to-data functionals.Results are compared between methodsand seasonal variability is observed in the transfer coefficients.展开更多
文摘Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information of free amino acids in food, we have carried out the experiments to quantitate the free amino acids by derivatized with NBD-F (4-fluoro-7-nitrobenzofurazan) and analyzed on reversed-phase UHPLC (ultra-high pressure liquid chromatography) equipped with ultraviolet visible detector. Almost all of food extracts contained free amino acids including GABA (T-amino butyrate). Contents of free amino acids vary considerably depending upon vegetables and fruits. Principal free amino acids found in vegetables and fruits were asparagine, glutamine, arginine and GABA, which are involved in important metabolic pathways in human. About 140 species of vegetables and fruits were subjected for the data base. All of the plants and fruits we examined exhibit significant amount of free amino acids, those are clearly distinct from data bases obtained after acid hydrolysis treated food samples. Since glutamate and GABA act as excitatory and inhibitory neurotransmitters in CNS, respectively; free amino acids in vegetables and fruits that we eat daily, should be an important source for the cellular metabolic activities.
文摘Time dependent carbon transfer coefficients are estimated using ecosystem exchange databy minimizing over variable observational intervals,Kalman filter,and variational minimization techniques.Transfer coefficients are determined by application of estimation procedures to subintervalsfrom a partition of the observational time period,minimizing the variance of analyzed errors withoutthe imposition of a priori transfer coefficient models in Kalman filters,and minimization with respectto transfer coefficients in variational fit-to-data functionals.Results are compared between methodsand seasonal variability is observed in the transfer coefficients.