Biological Activity of Conventional and Organic Pomegranate Juices: Antioxidant and Antimutagenic Potential.

None of the health claims about pomegranate juices has been approved yet by European Food Safety Authority (EFSA). There is a general perception among consumers that organic foods are healthier, tastier, and more nutritive than the conventional products. The aim of this research was to study the differences in the biological activity between ready-for-consumption juices obtained from pomegranates fruits grown under conventional and organic agricultural practices. Antioxidant activity has been evaluated by three methods (DPPH•, ABTS+, and FRAP), together with the total contents of phenolics and punicalagin (HPLC-DAD); besides, the Ames test was used to evaluate the antimutagenic potential of the juices. Pomegranate juice, either from conventionally or organically grown fruits, was antimutagenic (mean of 51 and 90 % for Salmonella typhimurium TA100 and TA98, respectively) and it was capable of protecting DNA from both, base-pair or frame-shift type of mutations. In fact, the antimutagenicity of conventional pomegranate juice was higher than that achieved by the organic sample; this finding was linked to a higher punicalagin content (201 and 104 mg L-1 for conventional and organic juices, respectively).

Inorganic and Total Arsenic Contents in Rice and Rice-Based Foods Consumed by a Potential Risk Subpopulation: Sportspeople.

One of the main routes of exposure to inorganic arsenic (i-As) in humans is food, especially rice and rice-based products. There are certain groups of consumers that could be highly exposed to i-As. Maximum levels of i-As have been issued for infants and young children by the European Union, but perhaps other groups are also at risk. Sportspeople could be one of those groups, due to their specific nutritional requirements, especially its high consumption of cereals, such as rice. Because of the well-known relationship between rice and i-As, the intake of i-As by sportspeople deserved especial attention and was estimated in Spain. This study demonstrated that rice-based products reached a maximum i-As content of 178 µg/kg, with a mean for all studied products of 56 µg/kg; the maximum contents were found in rice cakes (149 µg/kg) and brown rice (111 µg/kg). The estimated daily intake of i-As were 0.16 and 0.18 µg/kg bw (body weight)/d, in sportsmen and sportswomen, respectively. These values were below the BMDL01 , 0.3 to 8.0 µg/kg bw/d; thus, it can be concluded that the sportspeople group is not at a significant risk regarding the intake of i-As. However, further studies are needed to evaluate their whole diet and not only rice-based products. Finally, it is important to claim that companies producing rice products include as much information as possible about the rice used in their products, including rice percentage and geographical origin.

Screening antimutagenic and antiproliferative properties of extracts isolated from Jackfruit pulp (Artocarpus heterophyllus Lam).

The present focused on the study of the antimutagenic and antiproliferative potential of pulp Jackfruit (Artocarpus heterophyllus Lam) extract, using Salmonella typhimurium tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line M12.C3.F6 (murine B-cell lymphoma), respectively. Jackfruit pulp extract was sequentially fractionated by chromatography (RP-HPLC) and each fraction was tested for antimutagenic and antiproliferative activities. The organic extracts obtained from Jackfruit pulp reduced the number of revertants caused by aflatoxin B1 (AFB1) and proliferation of cells M12.C3.F6; a dose-response relationship was showed. Sequential RP-HPLC fractionation of the active extracts produced both antimutagenic and/or antiproliferative fractions. These results suggested that the Jackfruit contained compounds with chemoprotective properties to reduce the mutagenicity of AFB1, also proliferation of a cancer cell line.

Extruded films of blended chitosan, low density polyethylene and ethylene acrylic acid.

The obtaining of chitosan extruded films was possible by using low density polyethylene (LDPE) as a matrix polymer and ethylene-acrylic acid copolymer as an adhesive, in order to ensure adhesion in the interphase of the immiscible polymers. The obtained blend films were resistant; however, a reduction in the mechanical resistance was observed as chitosan concentration increased. The thermal stability of the films showed a certain grade of interaction between polymers as seen in FTIR spectra. The antifungal activity of the extruded films was assessed against Aspergillus niger and high inhibition percentages were observed, which may be mainly attributed to barrier properties of the extruded films and the limited oxygen availability, resulting in the inability of the fungi to grow. A low adherence of fungal spores to the material surface was observed, mainly in areas with chitosan clumps, which can serve as starting points for material degradation.

Seasonal variations in the concentrations of metals in Crassostrea corteziensis from Sonora, México.

This study examines seasonal variations in the concentrations of Cd, Cu, Pb, and Hg in experimentally cultured Crassostrea corteziensis, an oyster species known to have high resistance to physical and chemical stressors. The highest levels of Cd (4.92 mg/kg), Cu (3.45 mg/kg), and Pb (0.67 mg/kg) were detected in oyster samples collected during the summer, while Hg concentrations were similar (0.03 to 0.04 mg/kg) throughout all seasons. Results indicate that except for Cd, Crassostrea corteziensis accumulates metals to levels below those recommended by the US. FDA and the Mexican government. For Cd, its concentration correlates more strongly with the temperature of the oyster's environment rather than to the oyster growth cycle.

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.

Anti-mutagenic compounds from corn.

In previous studies with aflatoxin-contaminated corn an uncharacteristic response for AFB1 in the Salmonella/microsomal mutagenicity assay (Ames test) was observed and the presence of anti-aflatoxin factors in the corn was suggested. In the current study, corn was extracted and fractionated using thin layer chromatography (TLC) using different developing solvent systems and the Ames test was used to monitor for anti-mutagenic activity in the corn fractions. Both Salmonella tester strains TA98 and TA100 with metabolic activation (S9) were used. Several corn fractions, at different stages in the isolation and purification process, showed anti-mutagenic dose-responses when exposed to pure AFB1. Corti extracts were non-toxic to the tester strains and TLC fractions that showed the best anti-mutagenic dose-responses were selected for further partial characterization analyses.