Cryptococcus laurentii: a wild yeast for xylanase production from agricultural by-products.

The development of technologies that allow the production of enzymes at a competitive cost is of great importance for several biotechnological applications, and the use of agro-industrial by-products is an excellent alternative to minimize costs and reduce environmental impacts. This study aimed to produce endo-xylanases using agro-industrial substrates rich in hemicellulose as sources of xylan in culture media. For this purpose, the yeast Cryptococcus laurentti and five lignocellulosic materials (defatted rice bran, rice husk, corn cob, oat husks, and soybean tegument), with and without pretreatment, were used as a source of xylan for enzyme production.

Hydrolysates containing xylooligosaccharides produced by different strategies: Structural characterization, antioxidant and prebiotic activities.

This study explores the structural characterization, antioxidant and prebiotic activities of hydrolysates containing xylooligosaccharides (XOS) produced by different strategies: direct fermentation of beechwood xylan (FermBX) and enzymatic treatment of beechwood (EnzBX) and rice husk (EnzRH) xylans. EnzBX and EnzRH showed XOS with a backbone of (1 → 4)-linked-xylopyranosyl residues and branches of arabinose, galactose, and uronic acids. FermBX presented the highest content of total phenolic compounds (14 mg GAE/g) and flavonoids (0.

C-phycocyanin decreases proliferation and migration of melanoma cells: In silico and in vitro evidences.

The incidence and number of deaths caused by melanoma have been increasing in recent years, and the pigment C-phycocyanin (C-PC) appears as a possible alternative to treat this disease. So, the objective of this study was to combine in silico and in vitro analysis to understand the main anti-melanoma pathways exerted by C-PC. We evaluated the ability of C-PC to bind to the main cellular targets related in the progression of melanoma through molecular docking, and the reflection of this bind in the biological effects in the B16F10 cell line through in vitro analysis.

Purification of xylanases from Aureobasidium pullulans CCT 1261 and its application in the production of xylooligosaccharides.

Xylanolytic enzymes are involved in xylan hydrolysis, the main ones being endo-β-1,4-xylanases (xylanases). This can be applied in the bioconversion of lignocellulosic materials into value-added products such as xylooligosaccharides (XOS). This study aimed to establish a protocol for the purification of xylanases, as well as to characterize and apply the purified enzyme extract in the production of XOS.

Xylooligosaccharide Production with Low Xylose Release Using Crude Xylanase from Aureobasidium pullulans: Effect of the Enzymatic Hydrolysis Parameters.

Xylooligosaccharides (XOS) are non-digestible and fermentable oligomers that stand out for their efficient production by enzymatic hydrolysis and beneficial effects on human health. This study aimed to investigate the influence of the main reaction parameters of the beechwood xylan hydrolysis using crude xylanase from Aureobasidium pullulans CCT 1261, thus achieving the maximum XOS production. The effects of temperature (40 to 50 °C), reaction time (12 to 48 h), type of agitation, substrate concentration (1 to 6%, w/v), xylanase loading (100 to 300 U/g xylan), and pH (4.

Colour stability and antioxidant activity of C-phycocyanin-added ice creams after in vitro digestion.

C-phycocyanin (C-PC) is a protein with bioactive properties, which is found mainly in cyanobacteria and that is used as a natural food dye. Even though it is extensively studied, few authors have reported C-PC's colour stability and antioxidant activity when applied to food matrices. Therefore, the aim of this research was to evaluate the colour stability over time and the antioxidant capacity of a food grade C-PC extract applied to milk-based ice creams.

Xylooligosaccharides production from wheat middlings bioprocessed with Bacillus subtilis.

Prebiotic compounds are substrates selectively metabolized by beneficial gut microbiota causing a health-promoting effect. Despite some prebiotic carbohydrates have been largely studied, xylooligosaccharides (XOS) are important prebiotics derived from arabinoxylans, which are polysaccharides found in cereals. This study aimed to investigate the production of xylanolytic enzymes and XOS during bioprocessing of wheat middlings, a product derived from wheat flour production, using a probiotic Bacillus subtilis.

Cell pretreatment with ethylenediaminetetraacetic acid for selective extraction of C-phycocyanin with food grade purity.

C-phycocyanin (C-PC) is a natural blue dye, and depending on its purity, which is measured by the ratio between the absorbance of the chromophore (A ) and the absorbance of the proteins (A ), it can be used in food (purity > 0.7), cosmetics (purity > 1.5), and therapeutic treatments (purity > 4.

Raw Glycerol and Parboiled Rice Effluent for Carotenoid Production: Effect of the Composition of Culture Medium and Initial pH.

Search for naturally grown food has stimulated the biotechnological production of carotenoids. Therefore, the use of the yeast has been researched due to its abilities to assimilate different sources as substrates and to produce high amounts of carotenoids. Furthermore, alternative sources have been used as the culture medium to reduce costs and environmental impact.

Simultaneous production of proteases and antioxidant compounds from agro-industrial by-products.

The use of processes for simultaneous production of bioproducts as enzymes and bioactive compounds is an interesting alternative to reduce environmental impacts. Thus, the aim of this study was to produce simultaneously, using the biorefinery concept, both proteases and bioactive compounds with antioxidant activity from Bacillus sp. P45 cultivation by using different by-products.

Co-production of carbonic anhydrase and phycobiliproteins by Spirulina sp. and Synechococcus nidulans.

The aim of this work was to study the co-production of the carbonic anhydrase, C-phycocyanin and allophycocyanin during cyanobacteria growth. Spirulina sp. LEB 18 demonstrated a high potential for simultaneously obtaining the three products, achieving a carbonic anhydrase (CA) productivity of 0.

Production of Nanofibers Containing the Bioactive Compound C-Phycocyanin.

C-phycocyanin (C-PC) is a water-soluble phycobiliprotein present in light-harvesting antenna system of cyanobacteria. The nanostructures have not been widely evaluated, precluding improvements in stability and application of the C-PC. Electrospun nanofibers have an extremely high specific surface area due to their small diameter, they can be produced from a wide variety of polymers, and they are successfully evaluated to increase the efficacy of antitumor drugs.

Interference of salts used on aqueous two-phase systems on the quantification of total proteins.

In this study the interference of potassium phosphate, sodium citrate, sodium chloride and sodium nitrate salts on protein quantification by Bradford's method was assessed. Potassium phosphate and sodium citrate salts are commonly used in aqueous two-phase systems for enzyme purification. Results showed that the presence of potassium phosphate and sodium citrate salts increase the absorbance of the samples, when compared with the samples without any salt.

Modeling of ion exchange expanded-bed chromatography for the purification of C-phycocyanin.

This work is focused on the experimental evaluation and mathematical modeling of ion exchange expanded-bed chromatography for the purification of C-phycocyanin from crude fermentative broth containing Spirulina platensis cells. Experiments were carried out in different expansion degree to evaluate the process performance. The experimental breakthrough curves were used to estimate the mass transfer and kinetics parameters of the proposed model, using the Particle Swarm Optimization algorithm (PSO).

Effect of compressed fluids treatment on β-galactosidase activity and stability.

This study aimed at assessing the influence of different pressurized fluids treatment on the enzymatic activity and stability of a lyophilized β-galactosidase. The effects of system pressure, exposure time and depressurization rate, using propane, n-butane, carbon dioxide and liquefied petroleum gas on the enzymatic activity were evaluated. The β-galactosidase activity changed significantly depending on the experimental conditions investigated, allowing the selection of the proper compressed fluid for advantageous application of this biocatalyst in enzymatic reactions.

Purification of carbonic anhydrase from bovine erythrocytes and its application in the enzymic capture of carbon dioxide.

This work presents a study of industrially applicable techniques to obtain a biologically supported carbon dioxide capture system, based on the extraction of carbonic anhydrase from bovine blood. Carbonic anhydrase is a metalloenzyme which catalyzes the reversible hydration of carbon dioxide. The objective of this study was to establish conditions to obtain carbonic anhydrase from bovine erythrocytes and apply it in the capture of carbon dioxide.

Evaluation of the composition of culture medium for yeast biomass production using raw glycerol from biodiesel synthesis.

The work herewith investigated the production of yeast biomass as a source of protein, using Yarrowia lipolytica NRRL YB-423 and raw glycerol from biodiesel synthesis as the main carbon source. A significant influence of glycerol concentration, initial pH and yeast extract concentration on biomass and protein content was observed according to the 2v (5-1) fractional design. These factors were further evaluated using a central composite design and response surface methodology, and an empirical model for protein content was established and validated.

Strategy for a protein purification design using C-phycocyanin extract.

A variety of techniques have been developed for the separation and recovery of proteins. The cost of purifying the product is frequently determined by the desired quality of the final product, which is evaluated by measuring the purity. In this work the design of a protein purification process for C-phycocyanin, a phycobiliprotein that can be used in the food and medical industries, was established.

Maximization of beta-galactosidase production: a simultaneous investigation of agitation and aeration effects.

In this work, the agitation and aeration effects in the maximization of the beta-galactosidase production from Kluyveromyces marxianus CCT 7082 were investigated simultaneously, in relation to the volumetric enzyme activity and the productivity, as well as the analysis of the lactose consumption and production of glucose, and galactose of this process. Agitation and aeration effects were studied in a 2 L batch stirred reactor. A central composite design (2(2) trials plus three central points) was carried out.

Mathematical modeling and simulation of inulinase adsorption in expanded bed column.

A mathematical model for an expanded bed column was developed to predict breakthrough curves for inulinase adsorption on Streamline SP ion-exchange adsorbent, using a crude fermentative broth with cells as the feedstock. The kinetics and mass transfer parameters were estimated using the PSO (particle swarm optimization) heuristic algorithm. The parameters were estimated for each expansion degree (ED) using three breakthrough curves at initial inulinase concentrations of 65.

Separation of phycocyanin from Spirulina platensis using ion exchange chromatography.

This paper presents the evaluation of some important parameters for the purification of phycocyanin using ion exchange chromatography. The influences of pH and temperature on the equilibrium partition coefficient were investigated to establish the best conditions for phycocyanin adsorption. The equilibrium isotherm for the phycocyanin-resin system was also determined.

Solid state biosurfactant production in a fixed-bed column bioreactor.

Biosurfactants are surface active substances which reduce interfacial tension and are produced or excreted at the microbial cell surface. We evaluated the biosurfactant production by Aspergillus fumigatus and Phialemonium sp. in solid state processes using fixed-bed column reactors.