title: Imbibition of soybean seeds in warm water results in the release of copious amounts of Bowman-Birk protease inhibitor, a putative anticarcinogenic agent.
abstract: Protease inhibitors play a protective role against pathogenic microorganisms and herbivorous insects. The two predominant protease inhibitors of soybean seeds are the Kunitz trypsin inhibitor (KTI) and Bowman-Birk protease inhibitor (BBI). In this study, we report that soybean seeds incubated in warm water release large amounts of proteins into the surrounding media. Two-dimensional gel electrophoresis analysis of the seed exudates resulted in the separation of 93 distinct protein spots out of which 90 spots were identified by LC-MS/MS. The basic 7S globulin and the BBI are the two predominant proteins found in the soybean seed exudates. In addition to 7S and 11S seed storage proteins, others known to protect the seeds against pathogens and pests including KTI, peroxidase, α-galactosidase, and endo-1.3-β-glucanase were also identified in the seed exudates. Soybean seed exudate obtained by incubating the seeds in warm water was also able to inhibit the growth of human breast cancer cell line MCF-7. Since soybean seeds release large amounts of enzymatically active BBI when immersed in warm water, our procedure could be exploited as a simplified alternative method for the preparation of BBI concentrate which is being used as a cancer chemoprotective agent.
authors.affiliation: Plant Science Division, University of Missouri, 1-41 Agriculture Building, Columbia, Missouri 65211, USA.
authors.forename: Manoj H
authors.initials: MH
authors.lastname: Palavalli
authors.forename: Savithiry S
authors.initials: SS
authors.lastname: Natarajan
authors.forename: Thomas T Y
authors.initials: TT
authors.lastname: Wang
authors.forename: Hari B
authors.initials: HB
authors.lastname: Krishnan
mesh_terms: D016588:Anticarcinogenic Agents; D001943:Breast Neoplasms; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D006358:Hot Temperature; D006801:Humans; D010940:Plant Proteins / Q000032:analysis / Q000378:metabolism; D012639:Seeds / Q000378:metabolism*; D013025:Glycine max / Q000378:metabolism*; D014358:Trypsin Inhibitor, Bowman-Birk Soybean / Q000378:metabolism* / Q000494:pharmacology; D014361:Trypsin Inhibitors / Q000378:metabolism; D014867:Water
chemical_list: D016588:Anticarcinogenic Agents; D010940:Plant Proteins; D014358:Trypsin Inhibitor, Bowman-Birk Soybean; D014361:Trypsin Inhibitors; D014867:Water; D002918:Chymotrypsin