Partial chemical/structural elucidation of anti-mutagenic compounds from corn.
In this study, corn fractions obtained from an isolation process of anti-mutagenic factors in our previous research work (Burgos-Hernández et al., 2001), were subjected to several analyses for chemical/structural elucidation. The anti-mutagenic activity of these fractions was tested against aflatoxin B(1) (AFB(1)) and 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), a mutagen that does not require bioactivation. Two concentrations of this agent in the corn fractions were tested for anti-mutagenicity in the Salmonella/microsomal mutagenicity assay, using tester strain TA100 with no metabolic activation. Corn fractions tested showed evidence of anti-mutagenic activity by producing a dose-response type of relationship between a constant amount of MNNG and several concentrations of tested corn fraction. Five different varieties of yellow corn were tested in order to determine if the anti-mutagenic factors were intrinsic to corn. Variety of the corn did not show an effect on the reduction of the mutagenic potential of AFB(1) suggesting that anti-mutagenic compounds are intrinsic to corn. Four corn fractions, previously obtained after the isolation process were analyzed by MALDI-MS and GC-MS. MALDI-MS showed the presence of two groups of molecules or molecular fragments. The molecular mass of one group ranged from 250 to 370 m/z, the other ranged from 540 to 640 m/z. GC-MS identified linoleic acid as one of the compounds responsible for the anti-mutagenic activity present in corn.
Burgos-Hernández
A
A
Department of Food Science, Louisiana State University Agricultural Center, Baton Rouge, LA 70803-4200, USA. aburgos@guayacan.uson.mx
López-García
R
R
Njapau
H
H
Park
D L
DL
D016604:Aflatoxin B1 / Q000633:toxicity; D016587:Antimutagenic Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity; D005591:Chemical Fractionation / Q000379:methods; D002855:Chromatography, Thin Layer; D004305:Dose-Response Relationship, Drug; D008401:Gas Chromatography-Mass Spectrometry; D008769:Methylnitronitrosoguanidine / Q000633:toxicity; D009152:Mutagenicity Tests; D009153:Mutagens / Q000633:toxicity; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics; D013045:Species Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013329:Structure-Activity Relationship; D003313:Zea mays / Q000737:chemistry*
D016587:Antimutagenic Agents; D009153:Mutagens; D008769:Methylnitronitrosoguanidine; D016604:Aflatoxin B1