title: Evaluation of extraction solutions for biochemical analyses of the proteins in rice grains.
abstract: The influence of different extraction solutions on the proteins extracted from rice grains was investigated. The largest amounts of salt-soluble proteins were extracted with solutions supplemented with Tris-HCl at pH 8.0. Rice allergens were analyzed by multiplex immunodetection. Except for α-globulin extracted with the solutions at pH 8.0, which showed a low-molecular-weight band besides the main band, no significant solution-dependent difference among the allergens was found. Total proteins were extracted with four kinds of solution. The extraction of the basic subunit of glutelin was found to be SDS-dependent, and more protein was obtained with extraction solutions supplemented with SDS. The contents of α-globulin and α-amylase/trypsin inhibitors were higher in the extracts without SDS than with SDS. We conclude from the present data that, in order to obtain comparable data from rice grain salt-soluble and total protein analyses, differences in the protein extraction efficiency of solutions used should be taken into consideration.
authors.affiliation: National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan.
authors.forename: Gang-hua
authors.initials: GH
authors.lastname: Lang
authors.forename: Yukari
authors.initials: Y
authors.lastname: Kagiya
authors.forename: Mayumi
authors.initials: M
authors.lastname: Ohnishi-Kameyama
authors.forename: Kazumi
authors.initials: K
authors.lastname: Kitta
mesh_terms: D000485:Allergens / Q000302:isolation & purification*; D000510:Alpha-Globulins / Q000302:isolation & purification*; D002021:Buffers; D002523:Edible Grain / Q000737:chemistry*; D004591:Electrophoresis, Polyacrylamide Gel; D005983:Glutens / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D059625:Liquid-Liquid Extraction / Q000592:standards; D008970:Molecular Weight; D012275:Oryza / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012996:Solutions; D014361:Trypsin Inhibitors / Q000302:isolation & purification*; D000516:alpha-Amylases / Q000302:isolation & purification*
chemical_list: D000485:Allergens; D000510:Alpha-Globulins; D002021:Buffers; D012996:Solutions; D014361:Trypsin Inhibitors; D012967:Sodium Dodecyl Sulfate; D005983:Glutens; D000516:alpha-Amylases