Utilization of seawater and wastewater from shrimp production in the fermentation of papaya residues to ethanol.

Seawater (SW) and wastewater from shrimp production (WSP) were used as a solvent for the fermentation of papaya residues (Carica papaya) by Wickerhamomyces sp. UFFS-CE-3.1.2 and Saccharomyces cerevisiae CAT-1. For comparative purposes and evaluation of the effect of salinity, ultrapure water (UW) was used as control. Fermentative parameters were evaluated in Plackett-Burman planning to assess ethanol production's significant variables. Urea supplementation was the only variable not significant for the proposed process, suggesting that papaya residues contain all the nutrients needed for fermentation. The experiments conducted with the different water sources resulted in similar concentrations of ethanol. Maximum ethanol concentration was obtained after nine h of fermentation usingWickerhamomycessp. UFFS-CE-3.1.2 (27.31 ± 1.40 g L-1) and 12 h using S. cerevisiaeCAT-1 (24.53 ± 0.68 g L-1). This study demonstrated that SW and WSP could replace freshwater without affecting ethanol production. Papaya residues from the fruit and vegetable sectors can be considered a promising substrate source for ethanol production.

Fusarium oxysporum and Aspergillus sp. as Keratinase Producers Using Swine Hair From Agroindustrial Residues.

Technological processes mediated by microorganisms and enzymes are promising alternatives for treatment of recalcitrant residues. Keratinases hydrolyze keratin, the primary component of some wastes generated in many industrial activities. The present study was designed to evaluate strategies for obtaining keratinases produced by fungi using submerged fermentation and two residues as substrates, chicken feathers and swine hair. Two fungi isolated from feather residues showed potential for keratinase production, Fusarium oxysporum and Aspergillus sp. These were subjected to submerged fermentation using chicken feathers and swine hair prepared in three conditions (microbial concentration reduction, sterilization and hydrogen peroxide). The residual mass was quantified and tested for keratinase production. The most potent enzymatic extract was used in the precipitation technique with salts and organic solvents. The best results of enzymatic activity were obtained using F. oxysporum, on the 6thday of fermentation, obtaining 243.25 U mL-1 using sterilized swine hair as the substrate. Aspergillus sp. showed the highest keratinolytic activity on the 9thday, 113.50 U mL-1 using feathers as the substrate. The highest degradation percentage was 59.20% (w/w) in swine hair and the precipitation technique, with relative activities close to 50%. The results are promising for the application of residues and microorganisms in biotechnological processes of economic and environmental interest.

Advanced oxidation processes applied for color removal of textile effluent using a home-made peroxidase from rice bran.

Enzymes are becoming tools in industrial processes because of several advantages, including activity in mild environmental conditions, and high specificity. Peroxidase, for one, stably oxidizes several substrates. The present study aimed to develop advanced oxidation processes (AOP), using non-commercial rice bran peroxidase to remove color and toxicity of synthetic textile wastewater. Using a microwave and shaker system, we obtained 38.9% and 100% of effluent color removal after peroxidase treatment, respectively. In addition, the shaker system decants residual dye particles through filtration, providing the textile industry with an economical and environmentally viable alternative to effluent treatment. In toxicity tests results, both treatment systems damaged the used genetic material. This damage occurs because of industrial discharge of wastewater into water bodies; effluent dilution reduced this damage. The data suggest that peroxidase as a textile effluent treatment has potential uses in industrial processes, because rice bran peroxidase has demonstrated affinity with dyes.