Antimicrobial efficiency of chlorine dioxide and its potential use as anti-SARS-CoV-2 agent: mechanisms of action and interactions with gut microbiota.

Chlorine dioxide (ClO2) is a disinfectant gas with strong antifungal, antibacterial, and antiviral activities. Applied on hard, non-porous surfaces as an aqueous solution or gas, the ClO2 exerts antimicrobial activity through its interaction and destabilization of cell membrane proteins, as well as through DNA/RNA oxidation, triggering cell death. As for viruses, the ClO2 promotes protein denaturalization mechanisms, preventing the union between the human cells and the viral envelope. Currently, ClO2 has been pointed out as a potential anti-SARS-CoV-2 clinical treatment for use in humans with the ability to oxidize the cysteine residues in the spike protein of SARS-CoV-2, inhibiting the subsequent binding with the Angiotensin-converting enzyme type 2 receptor, located in the alveolar cells. Orally administered ClO2 reaches the gut tract and exacerbates the symptoms of COVID-19, generating a dysbiosis with gut inflammation and diarrhea as side effects, and once absorbed, produces toxic effects including methemoglobinemia and hemoglobinuria, which can trigger respiratory diseases. These effects are dose-dependent and may not be entirely consistent between individuals since the gut microbiota composition is highly heterogeneous. However, to support the use of ClO2 as an anti-SARS-CoV-2 agent, further studies focused on its effectiveness and safety both in healthy and immunocompromised individuals, are needed.

Active Compounds in Zingiber officinale as Possible Redox Inhibitors of 5-Lipoxygenase Using an In Silico Approach.

5-Lipoxygenase (5-LOX) converts arachidonic acid to lipidic inflammatory mediators such as leukotrienes (LTs). In diseases such as asthma, LTs contribute to a physiopathology that could be reverted by blocking 5-LOX. Natural products with anti-inflammatory potential such as ginger have been used as nutraceuticals since ancient times. 6-Gingerol and 6-shogaol are the most abundant compounds in the ginger rhizome; they possess anti-inflammatory, antioxidant, and chemopreventive properties. In the present study, 6-gingerol and 6-shogaol structures were analyzed and compared with two commercial 5-LOX inhibitors (zileuton and atreleuton) and with other inhibitor candidates (3f, NDGA, CP 209, caffeic acid, and caffeic acid phenethyl ester (CAPE)). The pharmacokinetics and toxicological properties of 6-gingerol, 6-shogaol, and the other compounds were evaluated. Targeted molecular coupling was performed to identify the optimal catalytic pocket for 5-LOX inhibition. The results showed that 6-gingerol and 6-shogaol follow all of the recommended pharmacokinetic parameters. These compounds could be inhibitors of 5-LOX because they present specific interactions with the residues involved in molecular inhibition. The current study demonstrated the potential of 6-gingerol and 6-shogaol as anti-inflammatory agents that inhibit 5-LOX, as they present a high level of performance in the toxicological analysis and could be catabolized by the cytochrome p450 enzymatic complex; however, 6-gingerol was superior in safety compared to 6-shogaol.

Effective microencapsulation of Enterococcus faecium in biopolymeric matrices using spray drying.

The objective of this work was to evaluate the potential of whey protein concentrate (WPC), native agave fructans (NAF), and their mixture (WPC-NAF, 1:1 w/w) as wall materials and evaluate the physicochemical properties and stability of encapsulated Enterococcus faecium during the spray drying, storage, and passage through the simulated gastrointestinal tests. The encapsulated microorganisms with WPC-NAF by spray drying showed greater viability (9.26 log CFU/g) and a higher microencapsulation yield (88.43%). They also had a smaller reduction in the cell count (0.61 log cycles), while the microcapsules produced with NAF had the greatest reduction in viability during the simulated gastrointestinal tests. Similarly, probiotics encapsulated with WPC-NAF revealed a higher survival rate (> 8 log CFU/g) when stored at a water activity of 0.328. The thermal analysis showed that the addition of NAF to the WPC produced a slight shift in the Tg towards temperatures higher than that shown by NAF. Therefore, this study provides evidence that the spray drying process was appropriate to encapsulate the probiotic strain Enterococcus faecium and that the mixture WPC-NAF protected it from adverse drying conditions and improved the viability of Enterococcus faecium during storage and simulated gastrointestinal tests, demonstrating that the combination of NAF and WPC as encapsulating material is adequate in the production of more stable microcapsules with potential application in various foods.Key Points• E. faecium was successfully encapsulated in WPC and NAF.• WPC-NAF offered protection to E. faecium in the gastrointestinal tests and during storage.• Aw around 0.328 positively influenced the viability of the microorganism during storage. Graphical abstract.

Microencapsulation of cocoa liquor nanoemulsion with whey protein using spray drying to protection of volatile compounds and antioxidant capacity.

The aim of this study was microencapsulated a nanoemulsion of cocoa liquor with whey protein by spray drying, and evaluate the effect of different inlet drying temperatures on the properties of microcapsules. The nanoemulsion showed a particle size of 202.13 nm, PdI of 0.424, and ζ-potential of -25.20 mV. The inlet drying temperature showed differences in physicochemical properties of microcapsules. Microcapsules presented good thermal stability and protection against the melting of cocoa liquor. Microcapsules obtained showed excellent yields of polyphenolic compounds (78-93%), and high retention of volatile compounds, especially of pyrazines. Greater microencapsulation yield of bioactive compounds and retention of volatile compounds was obtained at higher drying temperature (180 °C). Excellent stability of polyphenols content, antioxidant capacity, and volatile compounds of cocoa liquor were observed during storage of the microcapsules at different temperature conditions, indicating the feasibility of this powder for its incorporation into functional foods.

[Growth and photochemical efficiency of photosystem ii in seedlings of two varieties of Capsicum annuum L. inoculated with rhizobacteria and arbuscular mycorrhizal fungi]. / Crecimiento y eficiencia fotoquímica del fotosistema ii en plántulas de 2 variedades de Capsicum annuum L. inoculadas con rizobacterias u hongos micorrícicos arbusculares.

Plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) are a biological alternative for the sustainable management of Capsicum annuum L. This research work evaluated the effects of both PGPR and AMF on bell pepper and jalapeno pepper plants. Five bacterial strains isolated from several locations in Estado de Mexico were used: [P61 (Pseudomonas tolaasii), A46 (P. tolaasii), R44 (Bacillus pumilus), BSP1.1 (Paenibacillus sp.), and OLs-Sf5 (Pseudomonas sp.)], and three treatments with AMF [H1 (consortium isolated from pepper crops in the State of Puebla), H2 (Rhizophagus intraradices), and H3 (consortium isolated from the rhizosphere of lemon trees, State of Tabasco)]. In addition, a fertilized treatment (Steiner nutrient solution at 25%) and an unfertilized control were included. Seedlings of "Caloro" jalapeno pepper and "California Wonder" bell pepper were inoculated with AMF at seed sowing, and PGPR were inoculated after 15 days of seedling emergence; seedlings were grown under plant growth chamber conditions. P61 bacterium and H1 AMF consortia were the most effective microorganisms for jalapeno pepper whereas R44 bacterium and AMF H3 and H1 were the most effective for bell peppers, when compared to the unfertilized control. Furthermore, P61 and R44 bacteria showed beneficial effects on PSII efficiency.

Nutraceutical potential, and antioxidant and antibacterial properties of Quararibea funebris flowers.

The flowers of Quararibea funebris tree are an important component of tejate, a traditional Mexican beverage. The flowers exhibited a high concentration of total polyphenolic compounds, total carotenoids, and vitamin C. UPLC analysis revealed the presence of salicylic acid, kaemferol-3-O-glucoside, trans-cinnamic acid, rutin, scopoletin, l-phenylalanine, 4-coumaric acid and quercetin-3-glucoside, among others metabolites. The flowers exhibited volatile compounds as isolongifolene, α-cedrene, 2,5,5-trimethyl-2,3,4,5,6,7-hexahydro-1H-2,4a-ethanonaphthalene, while that linoleic acid, palmitic acid, and linolenic acid were the major fatty acids present in the oil extract. Magnesium, potassium, and calcium were the minerals most abundant in the flowers. In addition the methanolic extract of the flowers exhibited antimicrobial properties against the tested pathogenic microbial strains. In conclusion, these results showed that the Q. funebris flowers not only have an aromatic and flavoring power for the Tejate beverage, but also contains compounds with antioxidant, antimicrobial, and nutraceutical potential, which helps to explain its therapeutic uses.

Lauroylated, Acetylated, and Succinylated Agave tequilana Fructans Fractions: Structural Characterization, Prebiotic, Antibacterial Activity and Their Effect on Lactobacillus paracasei under Gastrointestinal Conditions.

The effect of chemical modification of fractions of native agave fructans (NAF), high performance (HPAF), and a high degree of polymerization (HDPAF) by lauroylation, acetylation, and succinylation reactions on their prebiotic activity, antibacterial properties were evaluated and survival of L. paracasei in a simulated gastrointestinal system. The characterization of the reactions was confirmed by NMR and FTIR. The lauroylated and succinylated fructan fractions showed higher antibacterial activity against pathogenic bacteria such as Escherichia coli, Enterococcus faecalis and Staphylococcus aureus than the unmodified ones. Analyses with L. paracasei showed that the acetylated fructan fractions had a greater prebiotic effect, and simulated gastrointestinal tests demonstrated that the acetylated and succinylated fractions favored the survival of L. paracasei during the gastrointestinal phase. The effect of modifying the agave fructans fractions on the evaluated properties depended on the structure, size, and polarity of each incorporated functional group, as well as the degree of polymerization and substitution of each fraction. These results show that the chemical modification of the fructan fractions analyzed improves their functional properties, offering an alternative in the food and pharmaceutical industry.

Dietary encapsulated Bifidobacterium animalis and Agave fructans improve growth performance, health parameters, and immune response in broiler chickens.

OBJECTIVE: The present study was conducted to evaluate the effects of dietary supplementation with Bifidobacterium animalis, Agave fructans, and symbiotic of both encapsulated on growth performance, feed efficiency, blood parameters, and immune status in broiler chickens, and to compare these with diets including antibiotic growth promoters and without additives. METHODS: A comparative experimental study was carried out with 135 male Ross 308 broiler chickens. Each trial was divided into 5 equal groups. Control group (CON) received a standard diet without growth promoter; GPA, a standard diet with colistin sulfate and zinc bacitracin (0.25 g/kg of feed); PRE, a standard diet with 1% Agave fructans; PRO, a standard diet with Bifidobacterium animalis (11.14±0.70 log CFU/g); SYM, a standard diet with B. animalis and Agave fructans. RESULTS: A significant decrease in food consumption was found for the GPA, PRE, and SYM, compared to the CON group. The results show a better feed conversion index in PRE and GPA with respect to the CON group with the highest conversion index. Interestingly, the weight of the gastrointestinal tract shows a statistically significant difference between GPA and PRE groups. Moreover, the length of the gastrointestinal tract of the GPA group was less than the PRE group. In the total leukocyte count, there was a statistically significant increase in the GPA group compared to the CON, PRE, and PRO groups, and the heterophiles-lymphocytes index was lower in PRO. Regarding the cytokines, interleukin 10 (IL-10) decreased in PRO compared to CON and PRE, while IL-1ß increased in the SYM group. CONCLUSION: Alternative treatments were shown to achieve similar productive results as growth-promoting antibiotics and showed improvement over diet without additives; however, they have immunomodulatory properties and improved the development of the gastrointestinal tract compared to the treatment of growth-promoting antibiotics.

Cocoa Nanoparticles to Improve the Physicochemical and Functional Properties of Whey Protein-Based Films to Extend the Shelf Life of Muffins.

A novel nanocomposite whey protein-based film with nanoemulsified cocoa liquor (CL) was prepared using one-stage microfluidization to evaluate the emulsion properties and the effect of CL on the film properties by response surface methodology (RSM). The results indicated that the number of cycles by microfluidization had a significant effect (p < 0.05) on the particle size and polydispersity of the nanoemulsion, with a polyphenol retention of approximately 83%. CL decreased the solubility (<21.87%) and water vapor permeability (WVP) (<1.57 g mm h-1 m-2 kPa-1) of the film. FTIR analysis indicated that CL modified the secondary protein structure of the whey protein and decreased the mechanical properties of the film. These results demonstrate that applying the film as a coating is feasible and effective to improve the shelf life of bakery products with a high moisture content. This nanocomposite film is easy to produce and has potential applications in the food industry.

The potential use of modified quinoa protein isolates in cupcakes: physicochemical properties, structure and stability of cupcakes.

The objective of this study was to evaluate the physicochemical, textural, sensory and microbiological stability of cupcakes during storage after the addition of different proportions of quinoa protein isolate modified by heat denaturation (QPI-HD) and freezing-lyophilization (QPI-FL). The cupcakes containing modified quinoa protein exhibited greater firmness and water activity than the control cupcake. The texture profile analysis (TPA) revealed that the cupcakes with modified quinoa protein were statistically different from those with unmodified protein isolate and the control cupcake. Moreover, cupcakes with quinoa protein modified by either heat or freezing had greater acceptance and preference on the part of consumers. In addition to this, these cupcakes showed lesser growth of molds after 10 days of storage; this indicated that the abovementioned additive could extend the shelf life of cupcakes. These results showed that the addition of modified quinoa protein led to cupcakes with better sensory and textural properties and greater stability during storage.

Chemical Lipophilization of Bovine α-Lactalbumin with Saturated Fatty Acyl Residues: Effect on Structure and Functional Properties.

Bovine α-lactalbumin (α-LA) was chemically modified by the covalent attachment of fatty acid residues of different length (lauroyl, palmitoyl, and stearoyl) to modify its functional and antioxidant properties. Structural changes, functional properties, and antioxidant capacity in the pH interval between 3 and 10 were analyzed. Surface properties were improved. The esterification increased the hydrophobic interactions leading to a reduction in the solubility dependent on the incorporation ratio of the fatty acid residues. Improvement in emulsifying, foaming, and antioxidant properties were observed when the length of the fatty acid chains was short and mostly at a basic pH. With these results in mind, experiments could be conducted for the technological applications of these derivatives in the food, pharmaceutical, and cosmetic industries.

Transforming the canonical piecewise-linear model into a smooth-piecewise representation.

A smoothed representation (based on natural exponential and logarithmic functions) for the canonical piecewise-linear model, is presented. The result is a completely differentiable formulation that exhibits interesting properties, like preserving the parameters of the original piecewise-linear model in such a way that they can be directly inherited to the smooth model in order to determine their parameters, the capability of controlling not only the smoothness grade, but also the approximation accuracy at specific breakpoint locations, a lower or equal overshooting for high order derivatives in comparison with other approaches, and the additional advantage of being expressed in a reduced mathematical form with only two types of inverse functions (logarithmic and exponential). By numerical simulation examples, this proposal is verified and well-illustrated.

Bioleaching of gold, copper and nickel from waste cellular phone PCBs and computer goldfinger motherboards by two Aspergillus nigerstrains.

In an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE), this research evaluated the bioleaching efficiency of gold (Au), copper (Cu) and nickel (Ni) by two strains of Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFICMs) and cellular phone printed circuit boards (PCBs). These three metals were analyzed for their commercial value and their diverse applications in the industry. Au-bioleaching ranged from 42 to 1% for Aspergillus niger strain MXPE6; with the combination of Aspergillus niger MXPE6 + Aspergillus niger MX7, the Au-bioleaching was 87 and 28% for PCBs and GFICMs, respectively. In contrast, the bioleaching of Cu by Aspergillus niger MXPE6 was 24 and 5%; using the combination of both strains, the values were 0.2 and 29% for PCBs and GFICMs, respectively. Fungal Ni-leaching was only found for PCBs, but with no significant differences among treatments. Improvement of the metal recovery efficiency by means of fungal metabolism is also discussed.

Crecimiento y eficiencia fotoquímica del fotosistema II en plántulas de 2 variedades de Capsicum annuum L. inoculadas con rizobacterias u hongos micorrícicos arbusculares / Growth and photochemical efficiency of photosystem II in seedlings of two varieties of Capsicum annuum L. inoculated with rhizobacteria and arbuscular mycorrhizal fungi

Una alternativa para el manejo sustentable en el cultivo de Capsicum annuum L. se ha enfocado en el uso de bacterias promotoras del crecimiento vegetal (BPCV) y hongos micorrícicos arbusculares (HMA). Esta investigación seleccionó BPCV y HMA sobre la base de su efecto en plantas de chile Bell Pepper y jalapeño. Se utilizaron 5 cepas bacterianas aisladas de diferentes localidades del estado de México (P61 [Pseudomonas tolaasii], A46 [P. tolaasii], R44 [Bacillus pumilus], BSP1.1 [Paenibacillus sp.] y OLs-Sf5 [Pseudomonas sp.]) y 3 tratamientos con HMA (H1 [consorcio aislado de la rizosfera de chile en el estado de Puebla], H2 [Rhizophagus intraradices]y H3 [consorcio aislado de la rizosfera de limón del estado de Tabasco]). Además, se incluyó un tratamiento fertilizado (solución Steiner 25%) y un testigo absoluto. Plántulas de chile jalapeño «Caloro¼ y pimiento Bell Pepper «California Wonder¼ fueron inoculadas con HMA en el momento de la siembra y con BPCV 15 días después de emerger, y crecidas bajo condiciones de cámara de ambiente controlado. En chile jalapenño, la mejor cepa bacteriana fue P61 y el mejor tratamiento de HMA fue el H1; en Bell Pepper la mejor cepa fue R44 y los mejores HMA fueron el H3 y el H1. Estos microorganismos incrementaron el crecimiento de plántulas de chile jalapenño y Bell Pepper en comparación con el testigo sin fertilizar. Asimismo, P61 y R44 beneficiaron positivamente la capacidad fotosintética del PSII.

Plant growth promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF) are a biological alternative for the sustainable management of Capsicum annuum L. This research work evaluated the effects of both PGPR and AMF on bell pepper and jalapeno pepper plants. Five bacterial strains isolated from several locations in Estado de Mexico were used: [P61 (Pseudomonas tolaasii), A46 (P. tolaasii), R44 (Bacillus pumilus), BSP1.1 (Paenibacillus sp.), and OLs-Sf5 (Pseudomonas sp.)], and three treatments with AMF [H1 (consortium isolated from pepper crops in the State of Puebla), H2 (Rhizophagus intraradices), and H3 (consortium isolated from the rhizosphere of lemon trees, State of Tabasco)]. In addition, a fertilized treatment (Steiner nutrient solution at 25%) and an unfertilized control were included. Seedlings of "Caloro" jalapeno pepper and "California Wonder" bell pepper were inoculated with AMF at seed sowing, and PGPR were inoculated after 15 days of seedling emergence; seedlings were grown under plant growth chamber conditions. P61 bacterium and H1 AMF consortia were the most effective microorganisms for jalapeno pepper whereas R44 bacterium and AMF H3 and H1 were the most effective for bell peppers, when compared to the unfertilized control. Furthermore, P61 and R44 bacteria showed beneficial effects on PSII efficiency.

Bioleaching of gold, copper and nickel from waste cellular phone PCBs and computer goldfinger motherboards by two Aspergillus nigerstrains

In an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE), this research evaluated the bioleaching efficiency of gold (Au), copper (Cu) and nickel (Ni) by two strains of Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFICMs) and cellular phone printed circuit boards (PCBs). These three metals were analyzed for their commercial value and their diverse applications in the industry. Au-bioleaching ranged from 42 to 1% for Aspergillus niger strain MXPE6; with the combination of Aspergillus niger MXPE6 + Aspergillus niger MX7, the Au-bioleaching was 87 and 28% for PCBs and GFICMs, respectively. In contrast, the bioleaching of Cu by Aspergillus niger MXPE6 was 24 and 5%; using the combination of both strains, the values were 0.2 and 29% for PCBs and GFICMs, respectively. Fungal Ni-leaching was only found for PCBs, but with no significant differences among treatments. Improvement of the metal recovery efficiency by means of fungal metabolism is also discussed.