A Combination of Apple Vinegar Drink with Bacillus coagulans Ameliorates High Fat Diet-Induced Body Weight Gain, Insulin Resistance and Hepatic Steatosis

Obesity is a worldwide epidemic characterized by excessive fat accumulation, associated with multiple comorbidities and complications. Emerging evidence points to gut microbiome as a driving force in the pathogenesis of obesity. Vinegar intake, a traditional remedy source of exogenous acetate, has been shown to improve glycemic control and to have anti-obesity effects. New functional foods may be developed by supplementing traditional food with probiotics. B. coagulans is a suitable choice because of its resistance to high temperatures. To analyze the possible synergic effect of Vinegar and B. coagulans against the metabolic alterations induced by a high fat diet (HFD), we fed twelve-week-old C57BL/6 mice with HFD for 5 weeks after 2 weeks of acclimation on a normal diet. Then, food intake, body weight, blood biochemical parameters, histology and liver inflammatory markers were analyzed. Although vinegar drink, either alone or supplemented with B. coagulans, reduced food intake, attenuated body weight gain and enhanced glucose tolerance, only the supplemented drink improved the lipid serum profile and prevented hepatic HFD-induced overexpression of CD36, IL-1β, IL-6, LXR and SREBP, thus reducing lipid deposition in the liver. The beneficial properties of the B. coagulans-supplemented vinegar appear to be mediated by a reduction in insulin and leptin circulating levels.

Influence of Cooking Conditions on Carotenoid Content and Stability in Porridges Prepared from High-Carotenoid Maize

Maize is a staple food crop in many developing countries, hence becoming an attractive target for biofortification programs toward populations at risk of micronutrient deficiencies. A South African white endosperm maize inbred line was engineered with a carotenogenic mini-pathway to generate high-carotenoid maize, which accumulates β-carotene, lutein and zeaxanthin. As maize porridge is a traditional meal for poor populations in sub-Saharan African countries, high-carotenoid maize was used as raw material to prepare different maize meals. The objective of this work was to assess the impact of popular home-cooking techniques and different cooking parameters (temperature, time and pH) on the final carotenoid content in the cooked product, using a spectrophotometric technique based on the mean absorption of carotenoids at 450 nm. Carotenoid levels were not only preserved, but also enhanced in high-carotenoid maize porridges. The carotenoid content was increased when temperatures ≤95 °C were combined with short cooking times (10-60 min). The most optimum thermal treatment was 75 °C/10 min. When treated under those conditions at pH 5, high-carotenoid maize porridges doubled the initial carotenoid content up to 88 μg/g dry weight. Regarding to cooking techniques, the highest carotenoid content was found when unfermented thin porridges were prepared (51 μg/g dry weight of high-carotenoid maize porridge). We conclude that high-carotenoid maize may contribute to enhance the dietary status of rural populations who depend on maize as a staple food.

The impact of Bacillus thuringiensis technology on the occurrence of fumonisins and other mycotoxins in maize

In many developing countries, maize is both a staple food crop and a widely-used animal feed. However, adventitious colonisation or damage caused by insect pests allows fungi to penetrate the vegetative parts of the plant and the kernels, the latter resulting in mycotoxin contamination. Maize seeds contaminated with fumonisins and other mycotoxins pose a serious threat to both humans and livestock. However, numerous studies have reported a significant reduction in pest damage, disease symptoms and fumonisin levels in maize hybrids expressing the Bacillus thuringiensis (Bt) gene cry1Ab, particularly in areas where the European corn borer is prevalent. When other pests are also present, the cry1Ab gene alone offers insufficient protection, and combinations of insecticidal genes are required to reduce damage to plants caused by insects. The combination of Cry1Ab protein with other Cry proteins (such as Cry1F) or Vip proteins has reduced the incidence of pests and, indirectly, mycotoxin levels. Maize hybrids expressing multiple Bt genes, such as SmartStax®, are less susceptible to damage by insects, but mycotoxin levels are not routinely and consistently compared in these crops. Bt maize has a greater economic impact on Fusarium toxins than aflatoxins. The main factors that determine the effectiveness of Bt hybrids are the type of pest and the environmental conditions, but the different fungal infection pathways must also be considered. An alternative strategy to reduce mycotoxin levels in crops is the development of transgenic plants expressing genes that protect against fungal infection or reduce mycotoxin levels by in situ detoxification. In this review article, we summarise what is known about the relationship between the cultivation of Bt maize hybrids and contamination levels with different types of mycotoxins.