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Summary: Tamarillo is an exotic fruit consumed regionally in Mexico, that contains a considerable amount of bioactive compounds, like antioxidants and fibre. Since its prebiotic potential was recently established, the aim of this work was to encapsulate two probiotic LAB strains with tamarillo extract and maltodextrin (15% and 20%) as encapsulant agents. Two strains at different maltodextrin concentrations (L. casei with 20% maltodextrin and L. plantarum with 15% maltodextrin) demonstrated higher encapsulation efficiency (90.64% and 92.03%, respectively) and viability after in vitro gastrointestinal digestion. Both microcapsules presented satisfactory flow properties and low moisture (4.19% and 3.91%) and water activity (0.32 and 0.33). During in vitro digestion, the total polyphenols content and the antioxidant activity decreased, but the encapsulating material in both treatments maintained an acceptable concentration of these bioactive compounds. The microcapsules were reconstituted to prepare a synbiotic non‐dairy beverage, and both treatments presented good acceptability (7.66 and 7.86 overall acceptance scores, respectively). These results indicate that, first, L. casei and L. plantarum recovered from heat shock during spray drying, enhancing their ability to survive to acidic stress during in vitro digestion; second, tamarillo extract is a good source of antioxidants and prebiotics and can be reconstituted to formulate, in this case, a synbiotic beverage to improve nutritional concern of consumers. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the growth, respiratory activity, and biodegradation of chlorpyrifos in cultures of Azotobacter vinelandii ATCC 12837. A strategy based on the modification of culture media and aeration conditions was carried out to increase the cell concentration of A. vinelandii, in order to favor and determine its tolerance to chlorpyrifos and its degradation ability. The culture in shaken flasks, using sucrose as a carbon source, significantly improved the growth compared to media with mannitol. When the strain was cultivated under oxygen-limited (5.5, 11.25 mmol L−1 h−1) and no-oxygen-limited conditions (22 mmol L−1 h−1), the growth parameters were not affected. In cultures in a liquid medium with chlorpyrifos, the bacteria tolerated a high pesticide concentration (500 ppm) and the growth parameters were improved even under conditions with a reduced carbon source (sucrose 2 g L−1). The strain degraded 99.6% of chlorpyrifos at 60 h of cultivation, in co-metabolism with sucrose; notably, A. vinelandii ATCC 12837 reduced by 50% the initial pesticide concentration in only 6 h (DT50). [ABSTRACT FROM AUTHOR]

Rhamnolipids are glycolipid biosurfactants that are primarily produced by Pseudomonas aeruginosa that have gained a great deal of interest for their numerous industrial applications and environmentally friendly properties. In this study, we explored the potential of waste canola oil as a low-cost and environmentally friendly substrate for the production of rhamnolipids by P. aeruginosa. Four different 23 full factorial designs were used to assess the effect of three independent factors on rhamnolipid production, including carbon source (canola oil and waste canola oil), nitrogen source [(NH4)2SO4 and NaNO3] and production time (7 and 14 days). The highest observed yield was 3585.31 ± 66.24 mg/L when P. aeruginosa was cultured for 14 days with 3% v/v waste canola oil and 4 g/L of NaNO3. The nitrogen source proved to be a crucial factor, as the use of NaNO3 rather than (NH4)2SO4 led to a 30-fold increase in production yield. The observed yield when waste canola oil was used was similar to, and even slightly higher than, that obtained using canola oil. Our results showed that waste canola oil has great potential for use as a carbon source for rhamnolipid production by P. aeruginosa, thus paving the way for the development of a low-cost, efficient, and environmentally friendly bioprocess for the production of rhamnolipids. [ABSTRACT FROM AUTHOR]

Species of the Cactaceae family inhabit areas with high temperatures, water scarcity, and nutrient-deficient soils. This is a result of complex processes such as physiological and physical adaptations, in addition to coevolution with endophytic microorganisms, which are inhabit plant tissues and can have relevant importance for the plant such as their establishment in rocky strata, the atmospheric nitrogen and phosphorus fixation by bacteria, or the antimicrobial action by fungi. Bioprospecting studies on endophytes of cacti are still scarce, so this work compiles the scientific literature on endophytic bacteria and fungi of cacti available in the databases Dialnet, DOAJ, EBSCO, Google académico, iSEEK, Redalyc, REDIB, Science Direct, SciFinder, SciELO, Springer, Web of Science and Wiley Online Library. The review yielded 22 papers published in 33 years; only 36% of them analyzed their bioactivity. The use of endophytes for biotechnological transfer is highlighted, mainly for social benefit (agricultural and medical purposes), as well as conservation. [ABSTRACT FROM AUTHOR]

Introduction: Introduction: obesity is a worldwide problem that predisposes to other health conditions. A direct relationship has been shown between obesity and genetic damage; the late is considered as an early marker of cancer in some cases. Objective: to evaluate the genetic damage and eating habits of children with obesity and normal weight. Methods: cross-sectional study conducted in school-age children. Genetic damage was assessed from buccal epithelial mucosal cells, through the quantification of nuclear abnormalities such as micronuclei, karyorrhexis, caryolysis, pyknosis and the presence of two nuclei. The nutritional evaluation was carried out through the analysis of weight, height and the evaluation of their diet through nutritional clinical records. Results: no significant differences were found in the number of nuclear abnormalities between the groups studied. However, some children with obesity showed higher number of nuclear abnormalities compared with children with normal weight. Regarding their eating habits, a positive correlation was found between weight and the consumption of free sugars and proteins in the diet. Conclusions: the lack of evidence that correlates micronuclei with nutritional status suggests that the presence of these abnormalities can be attributed to environmental or epigenetic factors. Special attention requires the study of diets similar to those habitually consumed by this population, in order to avoid their potential consequences. This study represents an important contribution in the evaluation of the possible health risks associated with childhood obesity. [ABSTRACT FROM AUTHOR]

Background: Millenary fermented beverages are a source of industrially important microorganisms. Aguamiel and pulque are traditional Mexican beverages of pre-Hispanic origin, with a microbial diversity that contributes to the different fermentations (lactic, alcoholic and acetic). The aim of this research was to characterize the Bacillus mojavensis (BF2A1) strain isolated from aguamiel and determine its probiotic potential. The strain was identified through Mass Spectrometry (MS), molecular techniques, as well as morphological and biochemical profiling. The probiotic activity of the BF2A1 strain and its response during the gastric simulation was determined. Results: The strain BF2A1 is a Gram-positive, spore-forming bacillus, positive for catalase, gammahemolysis, citrate, ornithine, grows at 7.5% NaCl, and acetoin, but negative for motility, indole, and methyl red. Its taxonomic identity was determined as B. mojavensis both by MALDI-TOF MS and sequencing of 16S rDNA. Its probiotic potential was demonstrated as BF2A1 was tolerant to pH 2 (OD620nm 0.2 89 ± 0.012), 0.3% bile salts (OD620nm 0.103 ± 0.089), 8% NaCl (OD620nm 0.254 ± 0.096), and 1% lysozyme (OD620nm 1.342 ± 0.078) compared to the probiotic strain Lactobacillus leichmannii ATCC 7830TM (Laclei). The antagonistic effect of BF2A1 against Escherichia coli (ATCC25922), Staphylococcus aureus (ATCC25923), and Candida albicans (ATCC60193) showed 25.5%, 8% and, 65% inhibitory growing effect, respectively. BF2A1 in the gastric simulation showed only a reduction of 1-2 log CFU/mL and showed after the intestinal phase a survival rate of 84.4% as compared to the control strains. Conclusions: This study shows that BF2A1 isolated from aguamiel is a bacterium with probiotic properties that can be used in different areas of Biotechnology. [ABSTRACT FROM AUTHOR]

Background: Palmitoleic acid is a fatty acid that possesses nutritional, health, and industrial applications. However, it accumulates in the seed oil of few plant species that often lack agronomic value. A bioinformatics approach was developed as a complementary tool to effort- and time-consuming traditional methods to identify palmitoleic acid-accumulating plant species. The approach involved identifying acyl-ACP desaturases with a sequence variation linked to a switch in the substrate preference from stearic to palmitic acid. Results: A PHI-BLAST analysis identified Handroanthus impetiginosus as a candidate species with two acyl- ACP desaturases with the desired sequence variation. A substrate docking analysis showed that the presence of phenylalanine at the bottom of the active site plays a similar structural role to that of tryptophan present in the same position in the divergent desaturase of the palmitoleic acid accumulator Dolichandra unguis-cati. The analysis of the genome of H. impetiginosus allowed the identification of four putative ferredoxins, three of which are heterotrophic type and have been linked to an increase in the activity of unusual acyl-ACP desaturases. RT-PCR results showed that both studied H. impetiginosus desaturases are expressed in the pod but not in the seeds, while all 4 ferredoxins are expressed in both tissues. GC–MS analysis confirmed the presence of palmitoleic acid in seed oil. Conclusions: These results suggest that the proposed bioinformatic approach can be a valuable compliment to traditional methods for the identification of plant species that accumulate palmitoleic acid. However, further improvements are needed, such as predicting seed expression of desaturases. [ABSTRACT FROM AUTHOR]

Encapsulation is an immobilization method characterized by restricting microbial cells to a delimited area while preserving their metabolic viability. This technique represents an alternative to improve the adaptive capacity of bacteria in the face of interactions with native microorganisms and environmental factors that limit their inoculation. This study aimed to evaluate the effect of Azotobacter vinelandii ATCC 12837 encapsulated in alginate-Na beads as an inoculant of tomato (Solanum Lycopersicum L) seedlings. Two inoculation treatments were carried out: liquid and encapsulated, and the control without microorganisms. Physiological variables, microbial viability, and the presence of A. vinelandii were determined by qPCR. Inoculation with A. vinelandii in liquid and encapsulated form favored seedling growth. Plants with the encapsulated inoculum significantly increased germination percentage (20%), stem diameter (38%), seedling height (34%), root length (69%), NO3 concentration (41%), and Na (30%); compared to the control. Encapsulation of A. vinelandii in alginate-Na macrocapsules allowed its establishment in the rhizosphere and was corroborated by viable count and molecular methods. The viability of the bacteria was maintained for 28 days using both inoculation methods, and not detected in the control treatment. [ABSTRACT FROM AUTHOR]