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Human Embryonic Kidney cells (HEK293) are a popular host for recombinant protein expression and production in the biotechnological industry. This has driven within both, the scientific and the engineering communities, the search for strategies to increase their protein productivity. The present work is inserted into this search exploring the impact of adding sodium acetate (NaAc) into a batch culture of HEK293 cells. We monitored, as a function of time, the cell density, many external metabolites, and the supernatant concentration of the heterologous extra-cellular domain ECD-Her1 protein, a protein used to produce a candidate prostate cancer vaccine. We observed that by adding different concentrations of NaAc (0, 4, 6 and 8 mM), the production of ECD-Her1 protein increases consistently with increasing concentration, whereas the carrying capacity of the medium decreases. To understand these results we exploited a combination of experimental and computational techniques. Metabolic Flux Analysis (MFA) was used to infer intracellular metabolic fluxes from the concentration of external metabolites. Moreover, we measured independently the extracellular acidification rate and oxygen consumption rate of the cells. Both approaches support the idea that the addition of NaAc to the culture has a significant impact on the metabolism of the HEK293 cells and that, if properly tuned, enhances the productivity of the heterologous ECD-Her1 protein.

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Increased prevalence of diabetes prompts the development of foods with reduced starch digestibility. This study analyzed the impact of adding soluble dietary fiber (inulin-IN; polydextrose-PD) to baked gluten-starch matrices (7.5-13%) on microstructure formation and in vitro starch digestibility. IN and PD enhanced water-holding capacity, the hardness of baked matrices, and lowered water activity in the formulated matrices, potentially explaining the reduced starch gelatinization degree as IN or PD concentration increased. A maximum gelatinization decrease (26%) occurred in formulations with 13% IN. Micro-CT analysis showed a reduction in total and open porosity, which, along with the lower gelatinization degree, may account for the reduced in vitro starch digestibility. Samples with 13% IN exhibited a significantly lower rapidly available glucose fraction (8.56 g/100 g) and higher unavailable glucose fraction (87.76 g/100 g) compared to the control (34.85 g/100 g and 47.59 g/100 g, respectively). These findings suggest the potential for developing healthier, starch-rich baked foods with a reduced glycemic impact.

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C. vulgaris is a unicellular microalgae, whose growth depends on the conditions in which it is found, synthesizing primary and secondary metabolites in different proportions. Therefore, we analyzed and established conditions in which it was possible to increase the yields of metabolites obtained at the flask level, which could then be scaled to the photobioreactor level. As a methodology, a screening design was applied, which evaluated three factors: type of substrate (sodium acetate or glycerol); substrate concentration; and exposure-time to red light (photoperiod: 16:8 and 8:16 light/darkness). The response variables were: cell division; biomass; substrate consumption; and antioxidant activity in intracellular metabolites (ABTS•+ and DPPH•). As a result, the sodium acetate condition of 0.001 g/L, in a photoperiod of 16 h of light, presented a doubling time (Td = 4.84 h) and a higher rate of division (σ = 0.20 h-1), having a final biomass concentration of 2.075 g/L. In addition, a higher concentration of metabolites with antioxidant activity was found in the sodium acetate (0.629 Trolox equivalents mg/L ABTS•+ and 0.630 Trolox equivalents mg/L DPPH•). For the glycerol, after the same photoperiod (16 h of light and 8 h of darkness), the doubling time (Td) was 4.63 h, with a maximum division rate of σ = 0.18 h-1 and with a biomass concentration at the end of the kinetics of 1.4 g/L. Sodium acetate under long photoperiods, therefore, is ideal for the growth of C. vulgaris, which can then be scaled to the photobioreactor level.

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Abstract The aqueous solubility of cefixime trihydrate (a water insoluble drug) using different hydrotropic agents was determined and solid dispersions of cefixime trihydrate were prepared by hydrotropic solubilization technique. The drugs content were determined. The aqueous solubility of v was increased many fold in presence of sodium acetate trihydrate as hydrotropic agent. This hydrotropic agent was used to prepare solid dispersion of cefixime trihydrate. Cefixime trihydrate and sodium acetate trihydrate were accurately weighed and taken in a 200 mL beaker. Distilled water 10-15 mL was taken to dissolve hydrotropic agent using heat (48-50 °C). The drug was then added to it and magnetically stirred till whole mass get viscous. The solid dispersions of cefixime trihydrate were characterized by XRD, DSC and IR studies. DSC thermogram, XRD and Infra-Red spectra were studied. Solid dispersions, thus prepared, showed faster release of the drug as compared to pure drug and physical mixture.

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Resumen Introducción. Haematococcus pluvialis es una microalga que produce astaxantina, un beta-caroteno y antioxidante muy usado en la industria. Para obtener una mayor producción de astaxantina se planteó como objetivo utilizar diferentes factores de estrés, en un biorreactor a escala de laboratorio de 5 litros. Metodología. Se cultivó la microalga en el medio RM, pH 6,8, temperatura 20±2°C, aire filtrado, iluminación con lámparas blancas 20h luz/4h oscuridad, irradianza 70 μE m-2s-1, diferentes concentraciones de acetato de sodio y cloruro de sodio. Se determinó crecimiento celular, cambios morfológicos y cuantificación de astaxantina y clorofila por espectrofotometría. Se realizó un análisis estadístico utilizando ANOVA (95%). Resultados. Utilizando 0,299 mg/L de acetato de sodio se obtuvo un crecimiento celular de 2,0 x 104 Cel/mL y una concentración de astaxantina de 2,530 μg/mL, mientras que con 1,6 mg/L de acetato de sodio el crecimiento celular fue de 3,5 x 104 Cel/mL y una concentración de astaxantina de 1,9 μg/ml. El tratamiento al cual se le adicionó 1,6 g/L de acetato de sodio y 6,4 g/L de cloruro de sodio presentó la mayor producción astaxantina 7,3 μg/ml. El tratamiento con acetato de sodio 0,320 g/L + cloruro de sodio 1,28 g/L presentó el mayor crecimiento celular con 1,64x105 células/ml. Conclusión. Esta investigación destaca la importancia de cultivar inicialmente la microalga utilizando el biorreactor Tecferm de 5 litros y después de su fase exponencial someterla a factores de estrés con acetato de sodio y cloruro de sodio lográndose así la mayor producción de astaxantina 7,325 μg/ml.

Abstract Introduction. Haematococcuspluvialis is a microalgae that produces astaxanthin, a beta-carotene and antioxidant widely used in industry. In order to obtain a higher production of astaxanthin, the objective was to use different stress factors, in a 5-liter laboratory-scale bioreactor. Methodology. The microalgae was cultivated in the RM medium, pH 6.8, temperature 20 ± 2°C, filtered air, illumination with white lamps 20h light/4h darkness, irradiance 70 μE m-2s-1, different concentrations of sodium acetate and chloride of sodium. Cell growth, morphological changes and quantification of astaxanthin and chlorophyll were determined by spectrophotometry. Statistical analysis was performed using ANOVA (95%). Results. Using 0.299 mg/L of sodium acetate a cell growth of 2.0 x 104 Cel/mL and an astaxanthin concentration of 2.530 μg/mL were obtained, while with 1.6 mg/L of sodium acetate the cell growth It was 3.5 x 104 Cel/mL and an astaxanthin concentration of 1.9 μg/mL. The treatment to which 1.6 g L of sodium acetate and 6.4 g/L of sodium chloride were added showed the highest astaxanthin production, 7.3 μg/ml. Treatment with 0.320 g/L sodium acetate + 1.28 g/L sodium chloride showed the highest cell growth with 1.64x105 cells/ml. Conclusion. This research highlights the importance of initially cultivating the microalgae using the 5-liter Tecferm bioreactor and, after its exponential phase, subjecting it to stress factors with sodium acetate and sodium chloride, thus achieving the highest production of 7.325 μg/ml astaxanthin.

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In this work, the influence of Sodium Acetate Trihydrate (SAT) on the gelling stage of a chitin hydrogel was studied. Characterization techniques, such as FTIR, Raman, solid-state NMR, Dielectric Spectroscopy, Small-angle X-ray scattering (SAXS), Wide-angle X-ray scattering (WAXS), and X-ray diffraction (XRD) were used to study the effect of SAT on the micro and nanostructure of the material in the wet, dry and freeze-dried states. It was demonstrated that the amount of SAT in the gelling solution can induce a variation in the supramolecular interaction among the polysaccharide chains, which leads to a change in the structural characteristics. In addition, it was observed that the polymer-water interactions are also altered by this structural ordering. Also, the affinity interaction with lysozyme was evaluated and an influence on the adsorption capacity was evidenced with the use of SAT. This could be an advance for biotechnological, biomedical, and food applications.

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Generally, the selection of fructans prebiotics and probiotics for the formulation of a symbiotic has been based on arbitrary considerations and in vitro tests that fail to take into account competitiveness and other interactions with autochthonous members of the intestinal microbiota. However, such analyzes may be a valuable step in the development of the symbiotic. The present study, therefore, aims to investigate the effect of lactobacilli strains and fructans (prebiotic compounds) on the growth of the intestinal competitor Klebsiella oxytoca, and to assess the correlation with short-chain fatty acids production. The short-chain fatty acids formed in the fermentation of the probiotic/prebiotic combination were investigated using NMR spectroscopy, and the inhibitory activities were assessed by agar diffusion and co-culture methods. The results showed that Lactobacillus strains can inhibit K. oxytoca, and that this antagonism is influenced by the fructans source and probably associated with organic acid production.

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Bacteria have the ability to produce biopolymers with different chemical properties, for different purposes and vary according to the bacterial strains and their physiological status, and these can be used as vaccine antigens. Haemophilus influenzae type b is a microorganism pathogenic to humans, which causes several types of infections. It is classified into six serotypes, the biopolymer of serotype b (Hib) being the most virulent, known as Poly Ribosylribitolphosphate (PRP). The aim of this work was to evaluate different candidate surfactants to be used in the PRP purification step, as well as the effects of ethanol in combination with sodium acetate. From all the surfactants used, 0.5% SDS proved to be potent in eliminating protein impurities and nucleic acids and in accordance with criteria of regulatory agencies. Regarding the combination of ethanol and sodium acetate to precipitate impurities, in the first fractionation step and polysaccharide, in the second fractionation step; the best conditions were: 40% ethanol without sodium acetate in the first stage and 60% ethanol containing 7% sodium acetate in the second stage. This improved condition resulted in nearly 100% polysaccharide recovery with relative purities higher than 100 for both protein and nucleic acid. In the traditional PRP purification process the final polysaccharide recovery was around 20% at the end of the process, while the new condition will result in at least 80% and within the purity criteria established by WHO for this polysaccharide.

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La inyección con monoiodo acetato de sodio (MIA) es ampliamente utilizada para producir osteoartritis en diversas articulaciones. El objetivo fue describir los daños histológicos provocados por MIA en la articulación humeral de rata. Se inyectó 0,1 mL de mezcla de 0,5 mg de MIA disuelto en 10 mL de solución fisiológica en la articulación humeral izquierda de 21 ratas SpragueDawley. Como control se utilizó la articulación derecha de cada rata. Se realizó la eutanasia a las 4, 8 y 12 semanas post inyección en grupos de 7 ratas. Los miembros mantenidos en formalina tamponada al 10% fueron descalcificados con EDTA por tres meses. Para la evaluación histológica se realizó la inclusión en parafina y se realizaron cortes coronales de 5 µm de espesor, para posterior tinción con azul de toluidina. En el cartílago sano, se observó una superficie lisa sin fisuras, todas las células de las zonas del cartílago se observaron normales. Se observaron cambios en el cartílago articular a partir de las 4 semanas post inyección, los condrocitos de la zona radial hipertróficos con gran producción de proteoglicanos. A las 12 semanas post inyección, se observa un gran deterioro, el espacio articular se ve disminuido, La superficie del cartílago se observa con fisuras y grietas que llegan hasta la zona radial. Las células alrededor de estas fisuras han desaparecido. Se observa una pérdida prominente de proteoglicanos debido a la débil tinción con azul de toluidina. La inyección articular con MIA produce lesiones similares a la OA. La gran ventaja de la OA inducida por MIA, es la facilidad de su aplicación y la rapidez en la progresión de OA.

Injection with monoiode sodium acetate (MIA) is widely used to produce osteoarthritis in various joints. The aim of this work was to describe the histological damage caused by MIA in the rat humeral joint; 0.1 mL of 0.5 mg mixture of MIA dissolved in 10 mL of physiological solution was injected into the left humeral joint of 21 Sprague-Dawley rats. As a control, the right joint of each rat was used. Euthanasia was performed at 4, 8 and 12 weeks post injection in groups of 7 rats. The samples maintained in 10 % buffered formalin were descaled with EDTA for three months. For histological evaluation, paraffin inclusion was performed and 5 µm thick coronal cuts were made for subsequent staining with toluidine blue. In the healthy cartilage, a smooth surface was observed, all cells in the cartilage areas were normal. Changes in articular cartilage were observed after 4 weeks post injection, hypertrophic radial chondrocytes with high proteoglycan production. At 12 weeks post injection, a great deterioration was observed, the articular space was diminished. The surface of the cartilage was observed with fissures and cracks that reach the radial zone. The cells around these fissures have disappeared. A prominent loss of proteoglycans was observed due to weak toluidine blue staining. Joint injection with MIA produced lesions similar to OA. The great advantage of the OA induced by MIA, is the ease of its application and the rapidity in the progression of OA.

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In this work, we propose a method that employed a smartphone to capture images obtained from a colorimetric spot test to determine ascorbic acid (AA) in Brazilian Amazon native and exotic fruits. The spot test reaction was based on reduction of Fe(III) by AA and further complexation with 1,10-phenanthroline. After optimization, the limit of detection was 8.5 × 10-7 mol L-1. Brazilian Amazon native fruits such as bacuri, cupuaçu, muruci, yellow mombin, as well as others as cashew, mango, orange and passion fruit, were analyzed. In order to determine the accuracy of this method, iodometric titration was used; results were in close agreement with a confidence level of 95% (paired t-test). Moreover, recoveries ranged from 87.1 to 116%. The method is economic, environmentally friendly, and portable, and might useful for small producers and family agriculture businesses unable to afford specialized laboratory analysis in the north region of Brazilian Amazon.

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The genus Paracoccidioides comprises known fungal pathogens of humans and can be isolated from different infection sites. Metabolic peculiarities in different members of the Paracoccidioides led us to perform proteomic studies in the presence of the two-carbon molecule acetate, which predominates in the nutrient-poor environment of the phagosome. To investigate the expression rates of proteins of different members of Paracoccidioides, including one isolate of P. lutzii (Pb01) and three isolates of P. brasiliensis (Pb03, Pb339, and PbEPM83), using sodium acetate as a carbon source, proteins were quantified using label-free and data-independent liquid chromatography-mass spectrometry. Protein profiles of the isolates were statistically analyzed, revealing proteins that were differentially expressed when the fungus was cultivated in a non-preferential carbon source rather than glucose. A total of 1,160, 1,211, 1,280, and 1,462 proteins were reproducibly identified and relatively quantified in P. lutzii and the P. brasiliensis isolates Pb03, Pb339, and PbEPM83, respectively. Notably, 526, 435, 744, and 747 proteins were differentially expressed among P. lutzii and the P. brasiliensis isolates Pb03, Pb339, and PbEPM83, respectively, with a fold-change equal to or higher than 1.5. This analysis revealed that reorganization of metabolism occurred through the induction of proteins related to gluconeogenesis, glyoxylic/glyoxylate cycle, response to stress, and degradation of amino acids in the four isolates. The following differences were observed among the isolates: higher increases in the expression levels of proteins belonging to the TCA and respiratory chain in PbEPM83 and Pb01; increase in ethanol production in Pb01; utilization of cell wall components for gluconeogenesis in Pb03 and PbEPM83; and increased ß-oxidation and methylcitrate cycle proteins in Pb01and PbEPM83. Proteomic profiles indicated that the four isolates reorganized their metabolism in different manners to use acetate as a carbon source.

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Agave fructans are increasingly important in food industry and nutrition sciences as a potential ingredient of functional food, thus practical analysis tools to characterize them are needed. In view of the importance of the molecular weight on the functional properties of agave fructans, this study has the purpose to optimize a method to determine their molecular weight distribution by HPLC-SEC for industrial application. The optimization was carried out using a simplex method. The optimum conditions obtained were at column temperature of 61.7°C using tri-distilled water without salt, adjusted pH of 5.4 and a flow rate of 0.36mL/min. The exclusion range is from 1 to 49 of polymerization degree (180-7966Da). This proposed method represents an accurate and fast alternative to standard methods involving multiple-detection or hydrolysis of fructans. The industrial applications of this technique might be for quality control, study of fractionation processes and determination of purity.

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Polysaccharides are substances that modify the biological response to several stressors. The present study investigated the antitumor activity of the soluble fraction of polysaccharides (SFP), extracted from cabernet franc red wine, in Walker-256 tumor-bearing rats. The monosaccharide composition had a complex mixture, suggesting the presence of arabinoglactans, mannans, and pectins. Treatment with SFP (30 and 60mg/kg, oral) for 14days significantly reduced the tumor weight and volume compared with controls. Treatment with 60mg/kg SFP reduced blood monocytes and neutrophils, reduced the tumor activity of N-acetylglucosaminidase, myeloperoxidase, and nitric oxide, increased blood lymphocytes, and increased the levels of tumor necrosis factor α (TNF-α) in tumor tissue. Treatment with SFP also induced the expression of the cell necroptosis-related genes Rip1 and Rip3. The antineoplastic effect of SFP appears to be attributable to its action on the immune system by controlling the tumor microenvironment and stimulating TNF-α production, which may trigger the necroptosis pathway.

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ABSTRACT The inhibition of Listeria monocytogenes ATCC 7644 on fresh-cut tomato was investigated using nisin alone, and in combinations with organic salts. Nisin at a concentration of 5000 UI/mL was introduced alone or in combination with an organic salt (sodium citrate or sodium acetate each at 3 and 5 g/100 mL each) on fresh-cut tomato previously inoculated with 108 CFU/mL of L. monocytogenes ATCC 7644. Chlorine at 200 ppm was used as a control. The inoculated samples were incubated at different temperatures (4, 10 and 25 °C) and examined at 0, 24, 48 and 72 h. The effects of the antimicrobial treatments on quality parameters of tomato (pH, soluble solids, titratable acidity and vitamin C) were also evaluated, and colour parameters were observed at the lowest storage temperature for 10 days. Both nisin and the organic salts inhibited growth of L. monocytogenes, but the combinations of two compounds were more effective. The nisin-sodium citrate (5%) combination was significantly (p ≤ 0.05) effective, while chlorine was least effective against L. monocytogenes. The quality parameters were substantially retained, especially at 4 °C, suggesting good shelf stability at a low temperature. These results substantiate the use of the cheap and eco-friendly approach to reducing this pathogen of health concern in common fresh produce.

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The inhibition of Listeria monocytogenes ATCC 7644 on fresh-cut tomato was investigated using nisin alone, and in combinations with organic salts. Nisin at a concentration of 5000 UI/mL was introduced alone or in combination with an organic salt (sodium citrate or sodium acetate each at 3 and 5 g/100 mL each) on fresh-cut tomato previously inoculated with 108 CFU/mL of L. monocytogenes ATCC 7644. Chlorine at 200 ppm was used as a control. The inoculated samples were incubated at different temperatures (4, 10 and 25 °C) and examined at 0, 24, 48 and 72 h. The effects of the antimicrobial treatments on quality parameters of tomato (pH, soluble solids, titratable acidity and vitamin C) were also evaluated, and colour parameters were observed at the lowest storage temperature for 10 days. Both nisin and the organic salts inhibited growth of L. monocytogenes, but the combinations of two compounds were more effective. The nisin-sodium citrate (5%) combination was significantly (p 0.05) effective, while chlorine was least effective against L. monocytogenes. The quality parameters were substantially retained, especially at 4 °C, suggesting good shelf stability at a low temperature. These results substantiate the use of the cheap and eco-friendly approach to reducing this pathogen of health concern in common fresh produce.(AU)

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The inhibition of Listeria monocytogenes ATCC 7644 on fresh-cut tomato was investigated using nisin alone, and in combinations with organic salts. Nisin at a concentration of 5000UI/mL was introduced alone or in combination with an organic salt (sodium citrate or sodium acetate each at 3 and 5g/100mL each) on fresh-cut tomato previously inoculated with 10(8)CFU/mL of L. monocytogenes ATCC 7644. Chlorine at 200ppm was used as a control. The inoculated samples were incubated at different temperatures (4, 10 and 25°C) and examined at 0, 24, 48 and 72h. The effects of the antimicrobial treatments on quality parameters of tomato (pH, soluble solids, titratable acidity and vitamin C) were also evaluated, and colour parameters were observed at the lowest storage temperature for 10 days. Both nisin and the organic salts inhibited growth of L. monocytogenes, but the combinations of two compounds were more effective. The nisin-sodium citrate (5%) combination was significantly (p≤0.05) effective, while chlorine was least effective against L. monocytogenes. The quality parameters were substantially retained, especially at 4°C, suggesting good shelf stability at a low temperature. These results substantiate the use of the cheap and eco-friendly approach to reducing this pathogen of health concern in common fresh produce.

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