Bored Coffee Beans for Production of Hyaluronic Acid by Streptococcus zooepidemicus

Bored coffee beans (BCBs) are the residues left from the pest Hypothenemus hampei that attacks coffee crops, resulting in enormous economic losses. The bioconversion of monosaccharides from BCBs into hyaluronic acid (HA) is appealing both for using the residues and given the high commercial value of HA. This study dealt with the production of HA using Streptococcus zooepidemicus by employing either acid (AcH) or enzymatic (EnH) hydrolyzates from BCBs. The highest release of monosaccharides (evaluated using surface response methodology) was obtained with EnH (36.4 g/L); however, S. zooepidemicus produced more HA (1.5 g/L) using AcH compared to EnH. Hydrolyzates from acetone-extracted BCBs yielded 2.7 g/L of HA, which is similar to the amount obtained using a synthetic medium (2.8 g/L). This report demonstrates the potential of hydrolyzates from bored coffee beans to produce HA by S. zooepidemicus.

A multivariate study of the rGO/g-C3N4 composite for the photocatalytic degradation of bisphenol A: Characterization, degradation kinetics, products identification, and ecotoxicity

Bisphenol A (BPA), a common polymer plasticizer, is a contaminant of emerging concern with endocrine disrupting activity. Among existing abatement methods, photodegradation demands easily fabricated, inexpensive, high photoactive catalysts, leading to non-toxic byproducts after degradation. It is proposed an optimized (surface response methodology) catalyst for those goals: graphitic carbon nitride impregnated with reduced graphene oxide. The method was based on the sonication of preformed particles followed by reduction with hydrazine in reflux, a methodology that allows for better reproducibility and larger specific surface areas. The catalyst removed 90% of BPA (100 mL, 100 µg L− 1) in 90 min under UV irradiation (365 nm, 26 W) compared to 50% with pure g-C3N4 (pseudo-first-order kinetics). Tests with radicals scavengers revealed that superoxide radical was the main oxidation agent in the system. By mass spectrometry, two major degradation products were identified, which were less ecotoxic than BPA towards a series of organisms, according to in silico estimations performed with the ECOSAR 2.0 software.

The effect of composition, microfluidization and process parameters on formation of oleogels for ice cream applications

The use of oleogels is an innovative and economical option for the technological development of some food products, among them ice creams. The aim of this study was to establish the best processing conditions to obtain an emulsion which form oleogels with the lowest ζ-potential and average droplet size (ADS) for use as ice cream base. Using surface response methodology (SRM), the effects of three numerical factors (microfluidization pressure, oil and whey protein concentration, WP) and four categorical factors (oil type, temperature, surfactant, and type of WP) on formation of emulsions were assessed. The response variables were ζ, ADS, polydispersity index (PDI), viscosity (η), hardness, cohesiveness and springiness. Additionally, a numerical optimization was performed. Two ice creams containing milk cream and oleogel, respectively were compared under the optimization conditions. Results suggest oleogels obtained from the microfluidization of whey and high oleic palm oil are viable for the replacement of cream in the production of ice cream.

Optimization of conditions for the production of laccase by Trametes villosa (Sw.) Kreisel and its application in the bio-treatment of sugar cane vinasse

Se optimizaron condiciones para la producción de lacasa por Trametes villosa mediante la metodología de superficie de respuesta: relación C:N, nivel de Cu+2 (mM) y tiempo de fermentación. El extracto crudo se inoculó en vinaza diluida al 25% y se evaluó el cambio en algunos parámetros de calidad de agua residual. La optimización produjo un aumento en la actividad de lacasa de 2,86 veces con respecto al medio no optimizado. Se observó reducción en los valores de DQO, fenoles y color en la vinaza tratada de 46,33%, 73,98% y 52,87% respectivamente. El pH aumentó de 6,50 a 6,57 y la actividad enzimática mostró un marcado aumento en medio con vinaza. Se confirma la utilidad de la metodología de superficie de respuesta en la optimización de condiciones en procesos de fermentación. Selected conditions for laccase production by Trametes villosa were optimized by surface response methodology: C:N ratio, Cu+2 level (mM), and fermentation time. The crude extract was inoculated on 25% (v/v) diluted sugarcane vinasse and some residual water quality parameters were evaluated. A 2.86-fold increase in the enzymatic activity was obtained upon optimization. Reduction of COD, phenol and color values on the treated vinasse were 46.33%, 73.98% and 52.87% respectively. pH increased from 6.50 to 6.57 and laccase enzymatic activity in vinasse media increased considerably. The advantage of surface respond methodologies for optimization of fermentation conditions is confirmed.