Partial chemical/structural elucidation of anti-mutagenic compounds from corn

• Published in: Toxicology (Amsterdam) 2001-09, Vol.166 (3), p.161-170
• Main Authors: Burgos-Hernández, A, López-Garcı́a, R, Njapau, H, Park, D.L
• Format: Article
• Language: English
• Subjects: 1-methyl-3-nitrosoguanidine; Aflatoxin B1 - toxicity; Anti-mutagenic compounds; Antimutagenic Agents - chemistry; Antimutagenic Agents - isolation & purification; Antimutagenic Agents - toxicity; Biological and medical sciences; Characterization; Chemical Fractionation - methods; Chemical mutagenesis; Chromatography, Thin Layer; Corn; Dose-Response Relationship, Drug; Gas Chromatography-Mass Spectrometry; Linoleic acid; Medical sciences; Methylnitronitrosoguanidine - toxicity; Mutagenicity Tests; Mutagens - toxicity; Salmonella TA 100 and TA 98; Salmonella typhimurium - drug effects; Salmonella typhimurium - genetics; Species Specificity; Spectrometry; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Structure-Activity Relationship; Toxicology; Zea mays; Zea mays - chemistry
• ISSN: 0300-483X; 1879-3185
• DOI: 10.1016/S0300-483X(01)00466-8

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.