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Rapid and sensitive method for determining free amino acids in plant tissue by high-performance liquid chromatography with fluorescence detection

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Acta Geochimica 2017年第4期36卷 680-696页

作者： Nengjian Zheng Huayun Xiao Zhongyi Zhang Xiaofei Gao Jingjing Zhao State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China Aquatic Ecohealth Group Key Laboratory of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

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.

关键词： HPLC OPA FMOC free amino acids Plant PLS-DA

Rapid Determination of free amino acids in Milk by Microchip Electrophoresis Coupled with Laser-induced Fluorescence Detection

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Chinese Journal of Chemistry 2012年第10期30卷 2517-2521页

作者：吴敏成双李刚汪志芳王清江何品刚方禹之 Department of Chemistry East China Normal University Shanghai 200062 China

A simple and sensitive method for determination of free amino acids in milk by microchip electrophoresis （MCE） coupled with laser-induced fluorescence （LIF） detection was developed. Seven kinds of standard amino ac- ids were derivated with sulfoindocyanine succinimidyl ester （Cy5） and then perfectly measured by MCE-LIF within 150 s. The parameters of MCE separation were carefully investigated to obtain the optimal conditions： 100 mmolo L^-1 sodium borate solution （pH 10.0） as running buffer solution, 0.8 kV as injection voltage, 2.2 kV as separation voltage etc. The linear range of the detection of amino acids was from 0.01 μmol·L^-1 to 1.0 μmol·L^-1 and the detection limit was as low as about 1.0 μmol·L^-1. This MCE-LIF method was applied to the measurements of free amino acids in actual milk samples and satisfactory experimental results were achieved.

关键词： free amino acids microchip electrophoresis laser-induced fluorescence detection milk

Dynamic changes in physicochemical property,biogenic amines content and microbial diversity during the fermentation of Sanchuan ham

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Food Science and Human Wellness 2024年第1期13卷 506-516页

作者： Zhongai Chen Hong Chen Huan Du Cong Chen Kaixiang Lu Qiaoli Xue Yongjin Hu College of Food Science and Technology Yunnan Agricultural UniversityKunming 650000China Institute of Food Processing Guizhou Academy of Agricultural SciencesGuiyang 550006China Editorial Department of Journal of Yunnan Agricultural University Yunnan Agricultural UniversityKunming 650000China

Sanchuan ham is appreciated in Yunnan Province,China,for its characteristic flavor and taste,while the microbial community structure and biogenic amines content remain unclear during fermentation processes.In this study,we explored the physicochemical property,biogenic amines concentration and microbial diversity of external and internal Sanchuan ham by high-throughput sequencing during the processing of Sanchuan ham.Results showed that the nitrite remained at a stable level of 0.15 mg/kg which was significantly lower than the national health standard safety level of 20 mg/kg.In addition,compared with fresh hams,the content of total free amino acids in ripe Sanchuan ham has grown 14 folds;sour and bitter were the main tastes of Sanchuan ham.Notably,the concentration of cadaverine was the highest of all biogenic amines during the entire fermentation period.At the bacterial phyla level,Firmicutes and Actinobacteria were the two main phyla,while at the genus level,Staphylococcus was a significant strain throughout the whole fermentation.Moreover,the dry stage has a great impact on the succession change of microbial community structure.Simultaneously,the change trends and composition of bacteria in the interior have slight discrepancies with those of the exterior of Sanchuan ham.

关键词： Sanchuan ham Nitrite cont ent free amino acids Cadaverine Staphylococcus

EFFECT OF INTRADUODENALLY INFUSED SOYBEAN SMALL PEPTIDE ON ABSORPTION OF free amino acids AND SMALL PEPTIDE IN LACTATING GOATS

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EFFECT OF INTRADUODENALLY INFUSED SOYBEAN SMALL PEPTIDE ON A...

Comparison of Flavor Substances in Dried Shrimp Products Processed by Litopenaeus Vannamei from Two Aquaculture Patterns

中国畜牧兽医学会动物营养学分会第八届全国会员代表大会暨...

作者： L.Wang~(1,2) H.Liu~1 Z.J.Cao~1 S.L.Li~(1*) S.J.Zhao~3 L.B.Wang~1 Z.J.Yang~1 1.National Key Laboratory of Animal Nutrition,College of Animal Science Agricultural University,Beijing,100193 2.College of Agriculture,Ningxia University,Ningxia,750021 3.Department of Feed Science,Wuhan Polytechnic University,Wuhan 430023,China

＜正＞The objective of the experiment was to study the effect of intraduodenally infused soybean small peptide （SSP）on absorption of free amino acids and small peptide in lactating goat.Four late lactating dairy goats （38.24±2.73kg BW,milk production 0.5～1.0kg/d）were used in a 4×4 Latin square design.Goats were fit- ted with duodenal cannulas and implanted with indwelling catheters in carotid artery, proximal and distal mesen-

关键词： small peptide free amino acids absorption lactating dairy goat

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Journal of Ocean University of China 2022年第6期21卷 1682-1690页

作者： HU Mengyue XUE Yong ZHAO Ling LIU Qi CAO Rong College of Food Science and Technology Ocean University of ChinaQingdao 266237China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdao 266071China Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology Qingdao 266237China

Dried shrimp is a popular aquatic food worldwide due to its unique flavor.However,its flavor qualities on the market remain uneven.This study aimed to compare flavor substances in dried shrimp processed by Litopenaeus vannamei from two aquaculture patterns(earthen pond and greenhouse)using amino acid automatic analyzer,high-performance liquid chromatography(HPLC),gas chromatography(GC)-ion mobility spectrometry(IMS),and GC-mass spectrometry(GC-MS).The results revealed that dried shrimp from earthen pond had significantly higher free amino acids and 5’-nucleotides than those from greenhouse(P<0.05),and their corresponding equivalent umami concentrations(EUCs)were 23.45 g MSG(100 g)^(−1)and 14.86 g MSG(100 g)^(−1),respectively.For volatile compounds,GC-IMS analysis indicated significant differences in volatile compounds between dried shrimp from different aquaculture patterns.According to the quantitative analysis of GC-MS,11 volatile compounds were identified as aroma-active compounds(AACs),of which six AACs(1-octen-3-ol,3-methylbutanal,nonanal,trimethylamine,2,5-dimethylpyrazine,and 2,3,5-trimethylpyrazine)were found in all dried shrimp samples.Although dried shrimp from greenhouse possesses higher OAVs,OAVs of(E,E)-2,4-nonadienal(fishy smell),and 3,5-diethyl-2-methylpyrazine(burnt smell)reached 171.2 and 333 respectively,imparting negative effects on flavor.In general,dried shrimp from earthen pond had a better flavor profile than those from greenhouse.

关键词： dried shrimp earthen pond greenhouse free amino acids flavor substances 5’-nucleotides GC-IMS GC-MS

Determination of 18 Kinds of amino acids in Fresh Tea Leaves by HPLC Coupled with Pre-column Derivatization

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Asian Agricultural Research 2018年第2期10卷 55-58,63页

作者： Shangwen DONG Tengfei LIU Minghui DONG Suzhou No. 10 High School of Jiangsu Province Suzhou 215000 China Suzhou Academy of Agricultural Sciences Suzhou 215155 China

A rapid and accurate quantitative method of high performance liquid chromatography( HPLC) with fluorescence detector has been developed for the analysis of 18 kinds of amino acids in fresh tea leaves. The samples were minced and mixed,and extracted with ultra pure water at 90℃ for 20 min. The 6-aminoquinolyl N-hydroxy-succinimidyl carbamate( AQC) was used as pre-column derivatization reagent. Gradient HPLC separation was performed on a C_(18) column( Symmetry C_(18),3. 9 mm × 15 cm,4 μm). Good linearity between concentrations and peak areas was achieved in the concentration range of 5. 0-250 μmol/L for 18 kinds of amino acids. The method was validated by the analysis of five replicates. The 18 kinds of amino acid standards were spiked in fresh tea leaf samples and the average recovery rate was 86. 25%-109. 05% with relative standard deviations( n = 5) ranging from 6. 03% to 10. 56%. The limit of detection( LOD) for the analytes was0. 05-1. 27 μmol/L. The method was successfully applied to the analysis of the 18 kinds of amino acids in fresh tea leaves from east Dongting and west Dongting mountains in Suzhou. The results indicate that the method is simple,rapid,precise and reliable.

关键词： Fresh tea leaves free amino acids Pre-column derivatization High performance liquid chromatography(HPLC)

Impact of potato psyllid （Hemiptera： Triozidae） feeding on free amino acid composition in potato

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Insect Science 2011年第6期18卷 663-670页

作者： Xiang-Bing Yang Nasir S. A. Malik Jose L. Perez Tong-Xian Liu Key laboratory of Applied Entomology Northwest A＆F University Yangling Shaanxi China Vegetable IPM Laboratory Texas AgriLife Research Texas A＆M System Kika de la Garza Subtropical Agricultural Research Center USDA-ARS Weslaco Texas USA

The impacts of potato psyllid （Bactericera cockerelli） feeding on potato foliage on the free amino acids （FAAs） composition in potato leaf and tubers were determined under greenhouse conditions. The free amino acids in plant extracts were separated by high-performance liquid chromatography, and in both leaf and tuber samples, at least 17 FAAs were detected. Psyllid feeding significantly changed the levels of several FAAs in both leaf and tuber samples. The concentration of leucine increased 1.5-fold, whereas that of serine and proline increased 2- and 3-fold, respectively. In contrast, the concentrations ofglutamic acid, aspartic acid and lyscine were significantly reduced by 42.0%, 52.1% and 27.5%, respectively. There were also significant changes in the levels of FAAs in the Zebra chip （ZC） infected tubers compared with the healthy tubers, and the levels of six of the FAAs increased, and the levels of nine of the FAAs decreased. The results from this study indicate that potato psyllid causes major changes in free amino acid composition of plant tissues, and this change in plant metabolism may contribute to the plant stress as indicated by increased levels of proline in the leaves and hence promoting the development of plant diseases such as ZC disease.

关键词： Bactericera cockerelli free amino acids HPLC potato stress Zebra chip

free amino acid content in trunk,branches and branchlets of Araucaria angustifolia(Araucariaceae)

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Journal of Forestry Research 2018年第6期29卷 1489-1496页

作者： Crizane Hackbarth Patricia Soffiatti Fla′vio Zanette Eny Iochevet Segal Floh Amanda Ferreira Macedo Henrique Aparecido Laureano Departamento de Fitotecnia e Fitossanitarismo Federal University of Parana(UFPR)Rua dos Funcionarios1540JuveveCuritibaPR 81531-990Brazil Departamento de Botanica Federal University of Parana(UFPR)Av.Cel.Francisco H.dos Santos100Jardim das AmericasCuritibaPR 81531-980Brazil Instituto de Biociencias University of Sao PauloRua do Matao277Sao PauloSP 05508-090Brazil Departamento de Estatstica Federal University of Parana(UFPR)Av.Cel.Francisco H.dos Santos100Jardim das AmericasCuritibaPR 81531-980Brazil

Araucaria angustifolia(Bertol.) O. Kuntze exhibits dimorphism in its stem structure, where the trunk is orthotropic and branches and branchlets(primary and secondary branches) are plagiotropic. These stems exhibit different behavior when used for vegetative propagation,and only segments of trunk can form a complete plant. The physiological and biochemical mechanisms that characterize these stems are still little known. The aim of this study was to describe the free amino acid profiles in trunks,branches, and branchlets of A. angustifolia. Segments of 5 cm in length were excised from young individuals below the stem apex. The needles were removed and samples were frozen and lyophilized. The determinations were made by high-performance liquid chromatography, and the results were expressed as lg/g fresh weight(FW). The trunks and branches had the highest content of total amino acids, which were 112.23 ± 20.57 lg/g FW and 111.97 ± 27.78 lg/g FW, respectively. The amino acids—glutamine, aspartate and c-aminobutyric acid and tyrosine—were noticeably higher in the three types of stems.In the trunk, a higher amount of asparagine and tryptophan,was also detected. Glutamic acid and glutamine were found in higher quantities in the branches. The branchlets had very low total amino acid content (30.79 ± 4.19 lg/g FW), wherein asparagine is the only amino acid not detected. Thus, it was observed that the profile of the free amino acid differs among trunks, branches, and branchlets in A. angustifolia, indicating that they perform different functions.

关键词： Brazilian pine Physiological mechanisms Stem’s dimorphism free amino acids

Survival,food consumption and growth of Norway lobster(Nephrops norvegicus)kept in laboratory conditions

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Integrative Zoology 2010年第3期5卷 256-263页

作者： Elena MENTE School of Agricultural Sciences Department of Ichthyology and Aquatic EnvironmentFytoko StreetGR-38446 N.Ionia MagnisiasGreece and 2School of Biological Sciences(Zoology)University of AberdeenTillydrone AvenueAB242TZ AberdeenUK

Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals.The results of the present study provide valuable information for feeding habits and growth of Nephrops norvegicus L.,1758)under laboratory conditions.The aim of the present study was to examine food consumption,growth and physiology of the Norway lobster N.norvegicus under laboratory conditions.N.norvegicus(15 g wet weight)were distributed into 100l tanks consisting of five numbered compartments each.They were fed the experimental diets(frozen mussels and pellets)for a period of 6 months.A group of starved Nephrops was stocked and fasted for 8 months.Although Nephrops grew well when fed the frozen mussels diet,feeding on a dry pellet feed was unsatisfactory.The starvation group,despite the fact that showed the highest mortality(50%),exhibited a remarkable tolerance to the lack of food supply.The study offers further insight by correlating the amino acid profiles of Nephrops tail muscle with the two diets.The deviations from the mussel’s diet for asparagine,alanine and glutamic acid suggest a deficiency of these amino acids in this diet.The results of the present study showed that the concentrations of free amino acids are lower in relative amount than those of protein-bound amino acids,except for arginine,proline and glycine.The present study contributes to the improvement of our knowledge on nutritional requirements of the above species.

关键词： food consumption free amino acids growth Nephrops norvegicus