title: Sorgoleone from root exudate inhibits mitochondrial functions.
abstract: The aim of this investigation was to determine if sorgoleone (SGL), a hydrophobic compound inSorghum bicolor (L.) Moench root exudate, interferes with mitochondrial functions. Tests were conducted on mitochondria isolated from etiolated soybean [Glycine max (L.) Merr.] and corn (Zea mays L.) seedlings. The data show SGL is a potent inhibitor of state 3 and state 4 respiration rates in both soybean and corn. Using either NADH, succinate, or malate as substrate, the I50 was about 0.5μM SGL for state 3 and 5.0μM for state 4 based on 0.3-0.5 mg mitochondrial protein. Absorption spectra indicate SGL blocks electron transport at theb-c 1 complex. These data show that disruption of mitochondrial function may be a mechanism of SGL-mediated growth inhibition previously reported and demonstrate a probable role of SGL inSorghum allelopathy.
authors.affiliation: Department of Biology, Southern Arkansas University, 71753, Magnolia, Arkansas.
authors.forename: J A
authors.initials: JA
authors.lastname: Rasmussen
authors.forename: A M
authors.initials: AM
authors.lastname: Hejl
authors.forename: F A
authors.initials: FA
authors.lastname: Einhellig
authors.forename: J A
authors.initials: JA
authors.lastname: Thomas