title: Structure and Activity Changes of Phytohemagglutinin from Red Kidney Bean (Phaseolus vulgaris) Affected by Ultrahigh-Pressure Treatments.
abstract: Phytohemagglutin (PHA), purified from red kidney beans (Phaseolus vulgaris) by Affi-Gel blue affinity chromatography, was subjected to ultrahigh-pressure (UHP) treatment (150, 250, 350, and 450 MPa). The purified PHA lost its hemagglutination activity after 450 MPa treatment and showed less pressure tolerance than crude PHA. However, the saccharide specificity and α-glucosidase inhibition activity of the purified PHA did not change much after UHP treatment. Electrophoresis staining by periodic acid-Schiff (PAS) manifested that the glycone structure of purified PHA remained stable even after 450 MPa pressure treatment. However, electrophoresis staining by Coomassie Blue as well as circular dichroism (CD) and differential scanning calorimetry (DSC) assay proved that the protein unit structure of purified PHA unfolded when treated at 0-250 MPa but reaggregates at 250-450 MPa. Therefore, the hemagglutination activity tends to be affected by the protein unit structure, while the stability of the glycone structure contributed to the remaining α-glucosidase inhibition activity.
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Yunjun
authors.initials: Y
authors.lastname: Lu
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Cencen
authors.initials: C
authors.lastname: Liu
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Mouming
authors.initials: M
authors.lastname: Zhao
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Chun
authors.initials: C
authors.lastname: Cui
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
authors.forename: Jiaoyan
authors.initials: J
authors.lastname: Ren
mesh_terms: D003296:Cooking / Q000295:instrumentation / Q000379:methods*; D006358:Hot Temperature; D027805:Phaseolus / Q000737:chemistry* / Q000201:enzymology; D010835:Phytohemagglutinins / Q000737:chemistry*; D010940:Plant Proteins / Q000032:analysis; D011312:Pressure; D012639:Seeds / Q000737:chemistry*; D000520:alpha-Glucosidases / Q000032:analysis
chemical_list: D010835:Phytohemagglutinins; D010940:Plant Proteins; D000520:alpha-Glucosidases
keywords: hemagglutination; phytohemagglutinin; red kidney bean; ultrahigh-pressure treatment; α-glucosidase inhibition