Bioprospecting of endophytic fungi from semidesert candelilla (Euphorbia antisyphilitica Zucc): Potential for extracellular enzyme production.

Endophytic microbial communities colonize plants growing under various abiotic stress conditions. Candelilla (Euphorbia antisyphilitica Zucc.) is a shrub that develops functionally in arid and semi-arid zones of Mexico; these conditions generate an association between the plant and the microorganisms, contributing to the production of enzymes as a defense mechanism for resistance to abiotic stress. The objective of this research was to isolate and identify endophyte fungi of candelilla and bioprospection of these endophytic fungi for enzyme production using candelilla by-products. Fungi were isolated and identified using ITS1/ITS4 sequencing. Their potency index (PI) was evaluated in producing endoglucanase, xylanase, amylase, and laccase. Fermentation was carried out at 30°C for 8 days at 200 rpm, with measurements every 2 days, using candelilla by-products as substrate. All fungi exhibited higher cellulase, amylase, and laccase activities on the 2nd, 6th, and 8th day of fermentation, respectively, of fermentation. The fungus Aspergillus niger ITD-IN4.1 showed the highest amylase activity (246.84 U/mg), the genus Neurospora showed the highest cellulase activity, reaching up to 13.45 FPU/mg, and the strain Neurospora sp. ITD-IN5.2 showed the highest laccase activity (3.46 U/mg). This work provides the first report on the endophytic diversity of E. antisyphilitica and its potential role in enzyme production.

Effect of different treatments on the preference of apple cubes dehydrated by a combined process.

The aim of this work was to determine the effect on consumer preference of dehydrated apple cubes caused by different modifications of a combined drying method. The combined process of convective-osmotic drying with pretreatment in solutions of CaCl(2) and citric acid was taken as the basic process, and was then modified to obtain six different treatments. The factors varied were the osmotic agent, the order of drying processes, and the addition of CaCl(2) to the osmotic solution. The drying kinetics of convective-osmotic treatment and the osmotic-convective process were studied. A sensory evaluation was conducted to determine the effect of these alterations in the drying process on the consumer preference for the product. The convective-osmotic treatment significantly reduced the time of processing. Water loss and solids gain were higher when fructose was used as the osmotic agent in the convective-osmotic process. According to the results of the preference test, only one of the modified processes showed significant preference compared with the basic process.

Effect of agave fructans on the production of short chain fatty acid in mice.

The aim of this study was to evaluate the effect of agave fructans on short chain fatty acid (SCFA) production in mice (C57BL/6). Animals were randomly divided into three groups (n = 8): control group (CG), fructans from Agave tequilana group (FG) (55 g per day/kg of body weight), and oligrofructose group (OG) (55 g per day/kg of body weight). Treatments were administered oral via for 6 weeks. After 24 days of treatment (phase 1), both treated groups exhibited elevated levels of acetic (12%) and propionic (FG 66% and OG 38%) acids in comparison with the CG. After 42 days of treatment (phase 2), FG had higher concentrations of acetic (33%) and propionic (73%) acids than the CG; while OG exhibited higher levels of butyric (12%) and propionic (35%) acids compared with the CG. Fructans from Agave tequilana improve the production of SCFA in mice, suggesting a prebiotic activity.

Effect of sourdough on quality and acceptability of wheat flour tortillas.

As an alternative on the search for functional food products, this study evaluated the use of sourdough in the preparation of wheat flour tortillas. The sourdough was elaborated with Lactobacillus sanfranciscensis and the wheat flour tortillas were prepared with different concentrations of mother sponge (5%, 15%, and 25%) and fermentation times (1 and 3 h) at room temperature (25 ± 2 °C). Quality (diameter, height, color, pH, stretchability scores, and Kramer shear cell results) of wheat tortillas was evaluated after 24 h of preparation. The mother sponge concentration and fermentation time affected some quality parameters and acceptability properties (taste, aroma, color, opacity, and rollability). In addition, the sourdough tortillas had higher stretchability values than control tortillas. Since most of the prepared sourdough tortillas had acceptability values similar to those of tortilla controls, the introduction of sourdough is a viable means to incorporate additional nutritional and nutraceutical value into wheat tortillas.