Anti-mutagenic compounds from corn

Antimutagenicity and antiproliferative studies of lipidic extracts from white shrimp (Litopenaeus vannamei)

An organic extract from fresh shrimp (Litopenaeus vannamei) was studied for antimutagenic and antiproliferative properties using Salmonella typhimurium tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. Shrimp extract was sequentially fractionated by thin layer chromatography (TLC) and each fraction was tested for antimutagenic and antiproliferative activities. Crude organic extracts obtained from shrimp reduced the number of revertants caused by aflatoxina B₁, showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/or antiproliferative fractions. These results suggested that the lipid fraction of the tested species contained compounds with chemoprotective properties that reduce the mutagenicity of AFB₁ and proliferation of a cancer cell line.

Insecticide residues in stored grains in Sonora, Mexico: quantification and toxicity testing

Food safety has acquired great attention by food importer and exporters. Food rejection or acceptance across international borders is based on the compliance with international food regulations. Due to the lack of recent data on pesticide residues in Mexican grains, this study focused on detecting and quantifying insecticide residues in stored wheat, corn, chickpeas, and beans, as well as to determine their mutagenic potential. Grains were sampled from primary storage sites in Sonora, Mexico. Malathion, chlorpyrifos, deltamethrin, cypermethrin, 4,4-DDE, 4,4-DDD and 4,4-DDT were analyzed in 135 samples. Grain samples were not mutagenic and most pesticide levels were within regulation limits.

Mutagencity and antimutagencity studies of lipidic extracts from yellowtail fish (Seriola lalandi), lisa fish (Mugil cephalus) and cazón fish (Mustelus lunulatus)

Organic extracts from fresh and smoked yellowtail fish (Seriola lalandi), lisa fish (Mugil cephalus) and cazon fish (Mustelus lunulatus) were tested for mutagenicity using Ames Salmonella tester strains TA98 and TA100 with metabolic activation (S9). Also, the antimutagenicity of the organic extract from yellowtail fish was tested against aflatoxin B1 (AFB1). Yellowtail fish extract was sequentially fractionated by thin-layer chromatography (TLC) and each fraction was also tested for antimutagenicity. None of the fresh species showed mutagenicity. Extract from smoked yellowtail showed the highest mutagenic potential among the smoked species tested. Organic extract from fresh yellowtail reduced the number of revertants caused by AFB1 showing a dose response type of relationship. Sequential TLC fractionation of the antimutagenic extract produced four antimutagenic fractions from fresh yellowtail fish. These results that the lipidic fraction of the species tested contains at least four compounds with chemoprotective properties that reduce the mutagenicity of AFB1.

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.