title: Effect of enzymatic treatment on sedimentation and flocculation abilities of solid particles in rice washing drainage and its relationship with protein profiles.
abstract: In this research, the protein participation that occurs with the flocculation and sedimentation phenomena caused by adding enzymes to solid particles derived from rice washing drainage and the electrostatic properties of the solid particle surfaces was examined. As seen in the results, adding protease to rice washing drainage decreased the protein content, strengthened the negative surface electron charge, and decreased the isoelectric point (IEP) value of the solid particles. In addition, about 25% of the proteins in the rice washing drainage still remained after enzyme treatment. Moreover, due to the enzyme treatment, specific and gradual degradations of 10, 13, and 16kDa of prolamin and 20-22kDa of gluterin basic subunit, both categorized in the basic protein group, were observed in an SDS-PAGE analysis. These results suggest that the flocculation and sedimentation of solid particles in rice washing drainage occur as a result of the formation of the IEP-dependent strengthening of the negative surface electron charge on the solid particle surface.
authors.affiliation: Hiroshima Kokusai Gakuin University, Aki-Ku, Hiroshima 739-0821, Japan. watanabe@hkg.ac.jp
authors.forename: Masanori
authors.initials: M
authors.lastname: Watanabe
authors.forename: Kazunori
authors.initials: K
authors.lastname: Ichinose
authors.forename: Kazuo
authors.initials: K
authors.lastname: Sasano
authors.forename: Yuich
authors.initials: Y
authors.lastname: Ozaki
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Tsuiki
authors.forename: Harutaro
authors.initials: H
authors.lastname: Hidaka
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Kanemoto
mesh_terms: D004591:Electrophoresis, Polyacrylamide Gel; D004798:Enzymes / Q000737:chemistry*; D005427:Flocculation; D005511:Food Handling / Q000379:methods*; D007526:Isoelectric Point; D012275:Oryza / Q000737:chemistry*; D010316:Particle Size; D010940:Plant Proteins / Q000032:analysis* / Q000737:chemistry; D055315:Prolamins / Q000737:chemistry; D013499:Surface Properties
chemical_list: D004798:Enzymes; D010940:Plant Proteins; D055315:Prolamins