Screening of chemiluminescence constituents of cereals and DPPH radical scavenging activity of gamma-oryzanol.
The chemiluminescence (CL) constituents of cereals were detected by CL using the H(2)O(2)-acetaldehyde system. The cereals tested, such as rice, millet and sorghum, exhibited various levels of CL activity. The gamma-oryzanol fraction was extracted from brown rice and separated into four constituents by HPLC. The four constituents were identified as cycloartenyl ferulate, 24-methylenecycroartanyl ferulate, campesteryl ferulate and beta-sitosteryl ferulate. Free radical scavenging activities with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and CL intensities of four constituents (gamma-oryzanol components) were measured and compared with that of gallic acid, which is a typical free radical scavenger. Four constituents scavenged DPPH radicals and scavenging activities were proportional to CL intensities. Concentrations of four CL constituents required to quench 50% (IC(50)) of the free radicals ranged from 0.9 to 1.1 mmol/L. We demonstrated that measurement of CL intensities was a rapid and convenient method for screening DPPH radical scavenging activities of rice.
Akiyama
Y
Y
Department of Environmental Bioremediation, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori Amemiyamachi, Aoba-ku, Sendai, Miyagi 981-8555, Japan. akiyama@arif.pref.akita.jp
Hori
K
K
Hata
K
K
Kawane
M
M
Kawamura
Y
Y
Yoshiki
Y
Y
Okubo
K
K
D015764:Bepridil / Q000031:analogs & derivatives* / Q000737:chemistry*; D001713:Biphenyl Compounds; D002851:Chromatography, High Pressure Liquid; D002523:Edible Grain / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry; D006801:Humans; D000960:Hypolipidemic Agents / Q000737:chemistry / Q000302:isolation & purification; D007202:Indicators and Reagents / Q000737:chemistry; D008163:Luminescent Measurements; D010666:Phenylpropionates / Q000737:chemistry* / Q000302:isolation & purification; D010851:Picrates
D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D005609:Free Radicals; D000960:Hypolipidemic Agents; D007202:Indicators and Reagents; D010666:Phenylpropionates; D010851:Picrates; D015764:Bepridil; C004931:1,1-diphenyl-2-picrylhydrazyl; C013172:gamma-oryzanol