Dietary Supplementation with Popped Amaranth Modulates the Gut Microbiota in Low Height-for-Age Children: A Nonrandomized Pilot Trial.

Amaranth has been recognized as a nutraceutical food because it contains high-quality proteins due to its adequate amino acid composition that covers the recommended requirements for children and adults. Since pre-Hispanic times, amaranth has been consumed as popped grain; the popping process improves its nutritive quality and improves its digestibility. Popped amaranth consumption has been associated with the recovery of malnourished children. However, there is no information on the impact that popped amaranth consumption has on gut microbiota composition. A non-randomized pilot trial was conducted to evaluate the changes in composition, structure, and function of the gut microbiota of stunted children who received four grams of popped amaranth daily for three months. Stool and serum were collected at the beginning and at the end of the trial. Short-chain fatty acids (SCFA) were quantified, and gut bacterial composition was analyzed by 16S rRNA gene sequencing. Biometry and hematology results showed that children had no pathology other than low height-for-age. A decrease in the relative abundance of Alistipes putredinis, Bacteroides coprocola, and Bacteroides stercoris bacteria related to inflammation and colitis, and an increase in the relative abundance of Akkermansia muciniphila and Streptococcus thermophiles bacteria associated with health and longevity, was observed. The results demonstrate that popped amaranth is a nutritious food that helps to combat childhood malnutrition through gut microbiota modulation.

Valorization of Parmentiera aculeata juice in growth of probiotics in submerged culture and their postbiotic production: a first approach to healthy foods.

Nowadays, functional foods are greatly accepted by consumers because they improve health and are new sources for substrates to be explored. In this sense, Parmentiera aculeata, a plant distributed in Mexico with beneficial effects on health, has not been chemically explored. In this work, P. aculeata juice was used as carbon source to promote the growth of two probiotic Lactobacillus strains during submerged fermentation. Taguchi's methodology with orthogonal array L9 was applied for culture conditions optimization. pH, agitation, and inoculum concentration variables, each with three levels, were evaluated and the best treatment was validated through a kinetic culture monitoring some postbiotics traits. We observed an increase in 1.76-times in cellular concentration of L. plantarum 14917, and the main produced postbiotics were short-chain fatty acids such as succinic, formic, acetic, propionic, and lactic acids, which are associated with the probiotic metabolism and are important for human health. In the best of our knowledge, this study is the first to describe the valorization of P. aculeata juice as substrate for growth of probiotic strains and future studies are required to gain further applications in functional food production.

Characterization of a Biofilm Bioreactor Designed for the Single-Step Production of Aerial Conidia and Oosporein by Beauveria bassiana PQ2.

Beauveria bassiana is an entomopathogenic fungus that is used for the biological control of different agricultural pest insects. B. bassiana is traditionally cultivated in submerged fermentation and solid-state fermentation systems to obtain secondary metabolites with antifungal activity and infective spores. This work presents the design and characterization of a new laboratory-scale biofilm bioreactor for the simultaneous production of oosporein and aerial conidia by B. bassiana PQ2. The reactor was built with materials available in a conventional laboratory. KLa was determined at different air flows (1.5-2.5 L/min) by two different methods in the liquid phase and in the exhaust gases. The obtained values showed that an air flow of 2.5 L/min is sufficient to ensure adequate aeration to produce aerial conidia and secondary metabolites by B. bassiana. Under the conditions studied, a concentration of 183 mg oosporein per liter and 1.24 × 109 spores per gram of support was obtained at 168 h of culture. These results indicate that the biofilm bioreactor represents a viable alternative for the production of products for biological control from B. bassiana.

Microbial diversity and biochemical profile of aguamiel collected from Agave salmiana and A. atrovirens during different seasons of year.

Aguamiel is a beverage produced by some Agave species that is consumed in its fresh or fermented form. Despite its uses and popularity, seasonal effects on its microbial and chemical profiles are unknown. In this study, using aguamiel collected from A. salmiana and A. atrovirens during different seasons, we identified microorganisms by sequencing the 16S and 18S rDNA genes and determined their chemical profiles. In total, 49 microbial strains were identified (38 bacteria and 11 yeasts). The highest richness and biodiversity were observed during winter and summer. Different lactic acid bacteria and yeast genera with potential industrial applications were identified, such as Acetobacter, Lactobacillus, Leuconostoc, and Clavispora. The analysis of the chemical profiles indicated the presence of maltooligosaccharides and fructooligosaccharides, which are associated with human health improvements, during spring in Agave aguamiel. Aguamiel can be used in the food industry due to its microbiological and chemical profiles.

Gene encoding a novel invertase from a xerophilic Aspergillus niger strain and production of the enzyme in Pichia pastoris.

ß-Fructofuranosidases or invertases (EC 3.2.1.26) are enzymes that are widely used in the food industry, where fructose is preferred over sucrose, because it is sweeter and does not crystallize easily. Since Aspergillus niger GH1, an xerophilic fungus from the Mexican semi-desert, has been reported to be an invertase producer, and because of the need for new enzymes with biotechnological applications, in this work, we describe the gene and amino acid sequence of the invertase from A. niger GH1, and the use of a synthetic gene to produce the enzyme in the methylotrophic yeast Pichia pastoris. In addition, the produced invertase was characterized biochemically. The sequence of the invertase gene had a length of 1770 bp without introns, encodes a protein of 589 amino acids, and presented an identity of 93% and 97% with invertases from Aspergillus kawachi IFO 4308 and A. niger B60, respectively. A 4.2 L culture with the constructed recombinant P. pastoris strain showed an extracellular and periplasmic invertase production at 72 h induction of 498 and 3776 invertase units (U), respectively, which corresponds to 1018 U/L of culture medium. The invertase produced had an optimum pH of 5.0, optimum temperature of 60 °C, and specific activity of 3389 U/mg protein, and after storage for 96 h at 4 °C showed 93.7% of its activity. This invertase could be suitable for producing inverted sugar used in the food industry.