Rapid and sensitive method for determining free amino acids in plant tissue by high-performance liquid chromatography with fluorescence detection
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摘要
This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linked fluorescence detector using a 150×4.6 mm Zorbax Eclipse AAA column. Plant tissue free amino acids(FAA)were extracted by ultrasonication with 5%(v/v) aqueous trifluoroacetic acid followed by ultrafiltration of extracts.The following analysis of amino acids was performed through programmed precolumn derivatization with orthophthalaldehyde and 9-fluorenylmethyl chloroformate reagents and efficient elution of derivatives within 26 min using binary gradient scheme. The method was validated over a concentration range of 4.5–450 μmol L~(-1)(μM).Separation analysis showed good selectivity(resolution>1.5) for most amino acids. The average repeatability(RSD%, relative standard deviation) of the analysis at seven calibration concentrations was below 4% and ranged from 1.13% to 12.04%. The intra-day mean coefficient of variation at two concentrations(22.5 and 90 μM) was within 2%, and the intermediate precision was less than 4%. The limits of detection were between 0.012 and 6.68 μM. The coefficients of determination(R2) of the linear calibration curves were from 0.9989 to 0.9999.When the method was applied to plant samples, the FAA recoveries at two spiked levels(25 and 100 μM) ranged from 67.0% to 108.9% with an average of 94.4%, and the precision was 0.26%–12.31% RSD. A specific application combining this method with optimized extraction and interference removal procedures was successfully used to determine the FAA pools in different plant tissues. Finally,a PLS-DA multivariate statistics model was validated for the classification of three plant species according to their FAA profiles.
This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linked fluorescence detector using a 150×4.6 mm Zorbax Eclipse AAA column. Plant tissue free amino acids(FAA)were extracted by ultrasonication with 5%(v/v) aqueous trifluoroacetic acid followed by ultrafiltration of extracts.The following analysis of amino acids was performed through programmed precolumn derivatization with orthophthalaldehyde and 9-fluorenylmethyl chloroformate reagents and efficient elution of derivatives within 26 min using binary gradient scheme. The method was validated over a concentration range of 4.5–450 μmol L~(-1)(μM).Separation analysis showed good selectivity(resolution>1.5) for most amino acids. The average repeatability(RSD%, relative standard deviation) of the analysis at seven calibration concentrations was below 4% and ranged from 1.13% to 12.04%. The intra-day mean coefficient of variation at two concentrations(22.5 and 90 μM) was within 2%, and the intermediate precision was less than 4%. The limits of detection were between 0.012 and 6.68 μM. The coefficients of determination(R2) of the linear calibration curves were from 0.9989 to 0.9999.When the method was applied to plant samples, the FAA recoveries at two spiked levels(25 and 100 μM) ranged from 67.0% to 108.9% with an average of 94.4%, and the precision was 0.26%–12.31% RSD. A specific application combining this method with optimized extraction and interference removal procedures was successfully used to determine the FAA pools in different plant tissues. Finally,a PLS-DA multivariate statistics model was validated for the classification of three plant species according to their FAA profiles.
This paper describes a reliable and rapid method for the complete separation and quantitation of twenty-five amino acids typically found in plants, based on reversed phase high-performance liquid chromatography–linked fluorescence detector using a 150×4.6 mm Zorbax Eclipse AAA column. Plant tissue free amino acids(FAA)were extracted by ultrasonication with 5%(v/v) aqueous trifluoroacetic acid followed by ultrafiltration of extracts.The following analysis of amino acids was performed through programmed precolumn derivatization with orthophthalaldehyde and 9-fluorenylmethyl chloroformate reagents and efficient elution of derivatives within 26 min using binary gradient scheme. The method was validated over a concentration range of 4.5–450 μmol L~(-1)(μM).Separation analysis showed good selectivity(resolution>1.5) for most amino acids. The average repeatability(RSD%, relative standard deviation) of the analysis at seven calibration concentrations was below 4% and ranged from 1.13% to 12.04%. The intra-day mean coefficient of variation at two concentrations(22.5 and 90 μM) was within 2%, and the intermediate precision was less than 4%. The limits of detection were between 0.012 and 6.68 μM. The coefficients of determination(R2) of the linear calibration curves were from 0.9989 to 0.9999.When the method was applied to plant samples, the FAA recoveries at two spiked levels(25 and 100 μM) ranged from 67.0% to 108.9% with an average of 94.4%, and the precision was 0.26%–12.31% RSD. A specific application combining this method with optimized extraction and interference removal procedures was successfully used to determine the FAA pools in different plant tissues. Finally,a PLS-DA multivariate statistics model was validated for the classification of three plant species according to their FAA profiles.
引文
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Amelung W,Zhang X(2001)Determination of amino acid enantiomers in soils.Soil Biol Biochem 33:553-562
Analytical Methods Committee(1994)Is my calibration linear?Analyst 119:2363-2366
Barker M,Rayens W(2003)Partial least squares for discrimination.J Chemom 17:166-173
Beckonert O,Keun HC,Ebbels TM,Bundy J,Holmes E,Lindon JC,Nicholson JK(2007)Metabolic profiling,metabolomic and metabonomic procedures for NMR spectroscopy of urine,plasma,serum and tissue extracts.Nat Protoc 2:2692-2703
Berg RA,Hoefsloot HC,Westerhuis JA,Smilde AK,Werf MJ(2006)Centering,scaling,and transformations:improving the biological information content of metabolomics data.BMC Genomics7:1
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Bhatty R,Finlayson A(1973)Extraction of nonprotein nitrogen from oilseed meals with different solvents.Cereal Chem 50:329-336
Bidlingmeyer BA,Cohen SA,Tarvin TL(1984)Rapid analysis of amino acids using pre-column derivatization.J Chromatogr BBiomed Sci Appl 336:93-104
Blanchard J(1981)Evaluation of the relative efficacy of various techniques for deproteinizing plasma samples prior to highperformance liquid chromatographic analysis.J Chromatogr BBiomed Sci Appl 226:455-460
BoucheN,Fromm H(2004)GABA in plants:just a metabolite?Trends Plant Sci 3:110-115
Brereton RG(2009)Chemometrics for pattern recognition,chapter 8.Wiley,New York,pp 117-118
Brereton RG,Lloyd GR(2014)Partial least squares discriminant analysis:taking the magic away.J Chemom 28:213-225
Calanni J,Berg E,Wood M,Mangis D,Boyce R,Weathers W,Sievering H(1999)Atmospheric nitrogen deposition at a conifer forest:response of free amino acids in Engelmann spruce needles.Environ Pollut 105:79-89
Chaimbault P,Petritis K,Elfakir C,Dreux M(1999)Determination of20 underivatized proteinic amino acids by ion-pairing chromatography and pneumatically assisted electrospray mass spectrometry.J Chromatogr A 855:191-202
Choi BK,Hercules DM,Gusev AI(2001)Effect of liquid chromatography separation of complex matrices on liquid chromatography-tandem mass spectrometry signal suppression.J Chromatogr A 907:337-342
Cohen SA,Michaud DP(1993)Synthesis of a fluorescent derivatizing reagent,6-aminoquinolyl-N-hydroxysuccinimidyl carbamate,and its application for the analysis of hydrolysate amino acids via high-performance liquid chromatography.Anal Biochem211:279-287
Cooper C,Packer N,Williams K(2001)Amino acid analysis protocol,chapters 1,2 and 10,vol 159.Springer,Berlin
Craig A,Cloarec O,Holmes E,Nicholson JK,Lindon JC(2006)Scaling and normalization effects in NMR spectroscopic metabonomic data sets.Anal Chem 78:2262-2267
Cuadros Rodr?guez L,Garc?a Campan?a A,Bosque Sendra J(1996)Statistical estimation of linear calibration range.Anal Lett29:1231-1239
De Jong C,Hughes GJ,Van Wieringen E,Wilson KJ(1982)Amino acid analyses by high-performance liquid chromatography:an evaluation of the usefulness of pre-column Dns derivatization.J Chromatogr A 241:345-359
Dettmer K,Aronov PA,Hammock BD(2007)Mass spectrometrybased metabolomics.Mass Spectrom Rev 26:51-78
Divino Filho J,Barany P,Stehle P,Furst P,Bergstrom J(1997)Free amino-acid levels simultaneously collected in plasma,muscle,and erythrocytes of uraemic patients.Nephrol Dial Transplant12:2339-2348
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Einarsson S,Josefsson B,Lagerkvist S(1983)Determination of amino acids with 9-fluorenylmethyl chloroformate and reversedphase high-performance liquid chromatography.J Chromatogr A282:609-618
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Ferri C,Hernandez-Orallo J,Modroiu R(2009)An experimental comparison of performance measures for classification.Pattern Recogn Lett 30:27-38
Filzmoser P,Liebmann B,Varmuza K(2009)Repeated double cross validation.J Chemom 23:160-171
Fritz C,Mueller C,Matt P,Feil R,Stitt M(2006)Impact of the C-Nstatus on the amino acid profile in tobacco source leaves.Plant Cell Environ 29:2055-2076
Furst P,Pollack L,Graser T,Godel H,Stehle P(1990)Appraisal of four pre-column derivatization methods for the high-performance liquid chromatographic determination of free amino acids in biological materials.J Chromatogr A 499:557-569
Gidman EA et al(2005)Metabolic fingerprinting for bio-indication of nitrogen responses in Calluna vulgaris heath communities.Metabolomics 1:279-285
Gromski PS,Xu Y,Hollywood KA,Turner ML,Goodacre R(2015)The influence of scaling metabolomics data on model classification accuracy.Metabolomics 11:684-695
Heems D,Luck G,Fraudeau C,Verette E(1998)Fully automated precolumn derivatization,on-line dialysis and high-performance liquid chromatographic analysis of amino acids in food,beverages and feedstuff.J Chromatogr A 798:9-17
Henderson J,Ricker R,Bidlingmeyer B,Woodward C(2000)Rapid,accurate,sensitive,and reproducible HPLC analysis of amino acids.Agilent Technologies.Technical Note 5980-1193E.J RSoc
Hermos?n I,Chicon RM,Cabezudo MD(2003)Free amino acid composition and botanical origin of honey.Food Chem83:263-268
Hesterberg T,Moore DS,Monaghan S,Clipson A,Epstein R(2005)Bootstrap methods and permutation tests.Introduc Pract Stat5:1-70
Hibbert DB,Gooding JJ(2005)Data analysis for chemistry,chapter 5.Oxford University Press,Oxford
Hill DW,Walters FH,Wilson TD,Stuart JD(1979)High performance liquid chromatographic determination of amino acids in the picomole range.Anal Chem 51:1338-1341
Huhn G,Schulz H(1996)Contents of free amino acids in Scots pine needles from field sites with different levels of nitrogen deposition.New Phytol 134:95-101
Huie CW(2002)A review of modern sample-preparation techniques for the extraction and analysis of medicinal plants.Anal Bioanal Chem 373:23-30
Hyotylainen T(2009)Critical evaluation of sample pretreatment techniques.Anal Bioanal Chem 394:743-758
Jones BN,Gilligan JP(1983)o-Phthaldialdehyde precolumn derivatization and reversed-phase high-performance liquid chromatography of polypeptide hydrolysates and physiological fluids.J Chromatogr A 266:471-482
Jones BN,Paabo S,Stein S(1981)Amino acid analysis and enzymatic sequence determination of peptides by an improved o-phthaldialdehyde precolumn labeling procedure.J Liq Chromatogr 4:565-586
Jones OA,Spurgeon DJ,Svendsen C,Griffin JL(2008)Ametabolomics based approach to assessing the toxicity of the polyaromatic hydrocarbon pyrene to the earthworm Lumbricus rubellus.Chemosphere 71:601-609
Kim HK,Verpoorte R(2010)Sample preparation for plant metabolomics.Phytochem Anal 21:4-13
Kuhn M,Johnson K(2013)Applied predictive modeling,vol 26.Springer,Berlin,p 236
Labadarios D,Moodie I,Shephard G(1984)Gas chromatographic analysis of amino acids in physiological fluids:a critique.J Chromatogr B Biomed Sci Appl 310:223-231
Lin CY,Wu H,Tjeerdema RS,Viant MR(2007)Evaluation of metabolite extraction strategies from tissue samples using NMRmetabolomics.Metabolomics 3:55-67
Liu X-Y,Xiao H-Y,Liu C-Q,Li Y-Y,Xiao H-W(2008)Stable carbon and nitrogen isotopes of the moss Haplocladium microphyllum in an urban and a background area(SW China):the role of environmental conditions and atmospheric nitrogen deposition.Atmos Environ 42:5413-5423
Liu X-Y,Koba K,Liu C-Q,Li X-D,Yoh M(2012)Pitfalls and new mechanisms in moss isotope biomonitoring of atmospheric nitrogen deposition.Environ Sci Technol 46:12557-12566
Lloyd GR,Ahmad S,Wasim M,Brereton RG(2009)Pattern recognition of inductively coupled plasma atomic emission spectroscopy of human scalp hair for discriminating between healthy and hepatitis C patients.Anal Chim Acta 649:33-42
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Mandrioli R,Mercolini L,Raggi MA(2013)Recent trends in the analysis of amino acids in fruits and derived foodstuffs.Anal Bioanal Chem 405:7941-7956
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Mohabbat T,Drew B(2008)Simultaneous determination of 33 amino acids and dipeptides in spent cell culture media by gas chromatography-flame ionization detection following liquid and solid phase extraction.J Chromatogr B 862:86-92
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Analytical Methods Committee(1994)Is my calibration linear?Analyst 119:2363-2366
Barker M,Rayens W(2003)Partial least squares for discrimination.J Chemom 17:166-173
Beckonert O,Keun HC,Ebbels TM,Bundy J,Holmes E,Lindon JC,Nicholson JK(2007)Metabolic profiling,metabolomic and metabonomic procedures for NMR spectroscopy of urine,plasma,serum and tissue extracts.Nat Protoc 2:2692-2703
Berg RA,Hoefsloot HC,Westerhuis JA,Smilde AK,Werf MJ(2006)Centering,scaling,and transformations:improving the biological information content of metabolomics data.BMC Genomics7:1
Bhatty R(1972)A note on trichloroacetic acid precipitation of oilseed proteins.Cereal Chem 49:I0
Bhatty R,Finlayson A(1973)Extraction of nonprotein nitrogen from oilseed meals with different solvents.Cereal Chem 50:329-336
Bidlingmeyer BA,Cohen SA,Tarvin TL(1984)Rapid analysis of amino acids using pre-column derivatization.J Chromatogr BBiomed Sci Appl 336:93-104
Blanchard J(1981)Evaluation of the relative efficacy of various techniques for deproteinizing plasma samples prior to highperformance liquid chromatographic analysis.J Chromatogr BBiomed Sci Appl 226:455-460
BoucheN,Fromm H(2004)GABA in plants:just a metabolite?Trends Plant Sci 3:110-115
Brereton RG(2009)Chemometrics for pattern recognition,chapter 8.Wiley,New York,pp 117-118
Brereton RG,Lloyd GR(2014)Partial least squares discriminant analysis:taking the magic away.J Chemom 28:213-225
Calanni J,Berg E,Wood M,Mangis D,Boyce R,Weathers W,Sievering H(1999)Atmospheric nitrogen deposition at a conifer forest:response of free amino acids in Engelmann spruce needles.Environ Pollut 105:79-89
Chaimbault P,Petritis K,Elfakir C,Dreux M(1999)Determination of20 underivatized proteinic amino acids by ion-pairing chromatography and pneumatically assisted electrospray mass spectrometry.J Chromatogr A 855:191-202
Choi BK,Hercules DM,Gusev AI(2001)Effect of liquid chromatography separation of complex matrices on liquid chromatography-tandem mass spectrometry signal suppression.J Chromatogr A 907:337-342
Cohen SA,Michaud DP(1993)Synthesis of a fluorescent derivatizing reagent,6-aminoquinolyl-N-hydroxysuccinimidyl carbamate,and its application for the analysis of hydrolysate amino acids via high-performance liquid chromatography.Anal Biochem211:279-287
Cooper C,Packer N,Williams K(2001)Amino acid analysis protocol,chapters 1,2 and 10,vol 159.Springer,Berlin
Craig A,Cloarec O,Holmes E,Nicholson JK,Lindon JC(2006)Scaling and normalization effects in NMR spectroscopic metabonomic data sets.Anal Chem 78:2262-2267
Cuadros Rodr?guez L,Garc?a Campan?a A,Bosque Sendra J(1996)Statistical estimation of linear calibration range.Anal Lett29:1231-1239
De Jong C,Hughes GJ,Van Wieringen E,Wilson KJ(1982)Amino acid analyses by high-performance liquid chromatography:an evaluation of the usefulness of pre-column Dns derivatization.J Chromatogr A 241:345-359
Dettmer K,Aronov PA,Hammock BD(2007)Mass spectrometrybased metabolomics.Mass Spectrom Rev 26:51-78
Divino Filho J,Barany P,Stehle P,Furst P,Bergstrom J(1997)Free amino-acid levels simultaneously collected in plasma,muscle,and erythrocytes of uraemic patients.Nephrol Dial Transplant12:2339-2348
Dupont DR,Keim PS,Chui AH,Bello R,Bozzini M,Wilson KJ(1989)A comprehensive approach to amino acid analysis.In:Hugli TE(ed)Techniques in protein chemistry.Academic Press,pp 284-294
Einarsson S,Josefsson B,Lagerkvist S(1983)Determination of amino acids with 9-fluorenylmethyl chloroformate and reversedphase high-performance liquid chromatography.J Chromatogr A282:609-618
Fabian V,Morvai M,Pinter-Szakacs M,Molnar-Perl I(1991)Standardization of cation-exchange clean-up prior to gas chromatography of amino acids.J Chromatogr A 553:87-92
Ferri C,Hernandez-Orallo J,Modroiu R(2009)An experimental comparison of performance measures for classification.Pattern Recogn Lett 30:27-38
Filzmoser P,Liebmann B,Varmuza K(2009)Repeated double cross validation.J Chemom 23:160-171
Fritz C,Mueller C,Matt P,Feil R,Stitt M(2006)Impact of the C-Nstatus on the amino acid profile in tobacco source leaves.Plant Cell Environ 29:2055-2076
Furst P,Pollack L,Graser T,Godel H,Stehle P(1990)Appraisal of four pre-column derivatization methods for the high-performance liquid chromatographic determination of free amino acids in biological materials.J Chromatogr A 499:557-569
Gidman EA et al(2005)Metabolic fingerprinting for bio-indication of nitrogen responses in Calluna vulgaris heath communities.Metabolomics 1:279-285
Gromski PS,Xu Y,Hollywood KA,Turner ML,Goodacre R(2015)The influence of scaling metabolomics data on model classification accuracy.Metabolomics 11:684-695
Heems D,Luck G,Fraudeau C,Verette E(1998)Fully automated precolumn derivatization,on-line dialysis and high-performance liquid chromatographic analysis of amino acids in food,beverages and feedstuff.J Chromatogr A 798:9-17
Henderson J,Ricker R,Bidlingmeyer B,Woodward C(2000)Rapid,accurate,sensitive,and reproducible HPLC analysis of amino acids.Agilent Technologies.Technical Note 5980-1193E.J RSoc
Hermos?n I,Chicon RM,Cabezudo MD(2003)Free amino acid composition and botanical origin of honey.Food Chem83:263-268
Hesterberg T,Moore DS,Monaghan S,Clipson A,Epstein R(2005)Bootstrap methods and permutation tests.Introduc Pract Stat5:1-70
Hibbert DB,Gooding JJ(2005)Data analysis for chemistry,chapter 5.Oxford University Press,Oxford
Hill DW,Walters FH,Wilson TD,Stuart JD(1979)High performance liquid chromatographic determination of amino acids in the picomole range.Anal Chem 51:1338-1341
Huhn G,Schulz H(1996)Contents of free amino acids in Scots pine needles from field sites with different levels of nitrogen deposition.New Phytol 134:95-101
Huie CW(2002)A review of modern sample-preparation techniques for the extraction and analysis of medicinal plants.Anal Bioanal Chem 373:23-30
Hyotylainen T(2009)Critical evaluation of sample pretreatment techniques.Anal Bioanal Chem 394:743-758
Jones BN,Gilligan JP(1983)o-Phthaldialdehyde precolumn derivatization and reversed-phase high-performance liquid chromatography of polypeptide hydrolysates and physiological fluids.J Chromatogr A 266:471-482
Jones BN,Paabo S,Stein S(1981)Amino acid analysis and enzymatic sequence determination of peptides by an improved o-phthaldialdehyde precolumn labeling procedure.J Liq Chromatogr 4:565-586
Jones OA,Spurgeon DJ,Svendsen C,Griffin JL(2008)Ametabolomics based approach to assessing the toxicity of the polyaromatic hydrocarbon pyrene to the earthworm Lumbricus rubellus.Chemosphere 71:601-609
Kim HK,Verpoorte R(2010)Sample preparation for plant metabolomics.Phytochem Anal 21:4-13
Kuhn M,Johnson K(2013)Applied predictive modeling,vol 26.Springer,Berlin,p 236
Labadarios D,Moodie I,Shephard G(1984)Gas chromatographic analysis of amino acids in physiological fluids:a critique.J Chromatogr B Biomed Sci Appl 310:223-231
Lin CY,Wu H,Tjeerdema RS,Viant MR(2007)Evaluation of metabolite extraction strategies from tissue samples using NMRmetabolomics.Metabolomics 3:55-67
Liu X-Y,Xiao H-Y,Liu C-Q,Li Y-Y,Xiao H-W(2008)Stable carbon and nitrogen isotopes of the moss Haplocladium microphyllum in an urban and a background area(SW China):the role of environmental conditions and atmospheric nitrogen deposition.Atmos Environ 42:5413-5423
Liu X-Y,Koba K,Liu C-Q,Li X-D,Yoh M(2012)Pitfalls and new mechanisms in moss isotope biomonitoring of atmospheric nitrogen deposition.Environ Sci Technol 46:12557-12566
Lloyd GR,Ahmad S,Wasim M,Brereton RG(2009)Pattern recognition of inductively coupled plasma atomic emission spectroscopy of human scalp hair for discriminating between healthy and hepatitis C patients.Anal Chim Acta 649:33-42
Magnusson B(2014)The fitness for purpose of analytical methods:a laboratory guide to method validation and related topics(2014),2nd edn.Eurachem,London,pp 30-33
Mandrioli R,Mercolini L,Raggi MA(2013)Recent trends in the analysis of amino acids in fruits and derived foodstuffs.Anal Bioanal Chem 405:7941-7956
Meyer H(1957)The ninhydrin reaction and its analytical applications.Biochem J 67:333
Mohabbat T,Drew B(2008)Simultaneous determination of 33 amino acids and dipeptides in spent cell culture media by gas chromatography-flame ionization detection following liquid and solid phase extraction.J Chromatogr B 862:86-92
Molero G,Aranjuelo I,Teixidor P,Araus JL,Nogues S(2011)Measurement of13C and15N isotope labeling by gas chromatography/combustion/isotope ratio mass spectrometry to study amino acid fluxes in a plant-microbe symbiotic association.Rapid Commun Mass Spectrom 25:599-607
Molero G,Tcherkez G,Araus JL,Nogues S,Aranjuelo I(2014)On the relationship between C and N fixation and amino acid synthesis in nodulated alfalfa(Medicago sativa).Funct Plant Biol 41:331-341
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