Impact of microaeration bioreactor on dissolved sulfide and methane removal from real UASB effluent for sewage treatment.

Two bioreactors were investigated as an alternative for the post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor treating domestic sewage, aiming at dissolved sulfide and methane removal. The bioreactors (R-control and R-air) were operated at different hydraulic retention times (HRT; 6 and 3 h) with or without aeration. Large sulfide and methane removal efficiencies were achieved by the microaerated reactor at HRT of 6 h. At this HRT, sulfide removal efficiencies were equal to 61% and 79%, and methane removal efficiencies were 31% and 55% for R-control and R-air, respectively. At an HRT of 3 h, sulfide removal efficiencies were 22% (R-control) and 33% (R-air) and methane removal did not occur. The complete oxidation of sulfide, with sulfate formation, prevailed in both phases and bioreactors. However, elemental sulfur formation was more predominant at an HRT of 6 h than at an HRT of 3 h. Taken together, the results show that post-treatment improved the anaerobic effluent quality in terms of chemical oxygen demand and solids removal. However, ammoniacal nitrogen was not removed due to either the low concentration of air provided or the absence of microorganisms involved in the nitrogen cycle.

Quality improvement and geographical indication of cachaça (Brazilian spirit) by using locally selected yeast strains.

AIMS: In order to improve the quality and to create a biological basis for obtainment of the protected denomination of origin (PDO), indigenous yeast were isolated and characterized for use in Salinas city (the Brazilian region of quality cachaça production). MATERIAL AND METHODS: Seven thousand and two hundred yeast colonies from 15 Salinas city distilleries were screened based on their fermentative behaviour and the physicochemical composition of cachaça. Molecular polymorphic analyses were performed to characterize these isolates. RESULTS: Two Saccharomyces cerevisiae strains (nos. 678 and 680) showed appropriate characteristics to use in the cachaça production: low levels of acetaldehyde and methanol, and high ethyl lactate/ethyl acetate ratio respectively. They also presented polymorphic characteristics more closely related between themselves even when compared to other strains from Salinas. CONCLUSIONS: The application of selected yeast to cachaça production can contribute for the improvement of the quality product as well as be used as a natural marker for PDO. SIGNIFICANCE AND IMPACT OF THE STUDY: This study suggests that the use of selected yeast strains could contribute to obtain a cachaça similar to those produced traditionally, while getting wide acceptation in the market, yet presenting more homogeneous organoleptic characteristics, and thus contributing to the PDO implementation.

Occurrence of pharmaceuticals and endocrine disruptors in raw sewage and their behavior in UASB reactors operated at different hydraulic retention times.

This work investigated the occurrence of pharmaceuticals and endocrine disrupting compounds (EDCs) in raw sewage (from Belo Horizonte city, Minas Gerais state, Brazil) and assessed their behavior in demo-scale upflow anaerobic sludge blanket reactors (UASB reactors) operated at different hydraulic retention times (HRT). The dissolved concentration of the studied micropollutants in the raw and treated sewage was obtained using solid phase extraction (SPE) followed by analysis in a liquid chromatography system coupled to a hybrid high resolution mass spectrometer consisting of an ion-trap and time of flight (LC-MS-IT-TOF). The natural (estradiol) and synthetic (ethinylestradiol) estrogens were hardly detected; when present, however, their concentrations were lower than the method quantification limits. The concentrations of bisphenol A and miconazole in raw sewage were similar to that reported in the literature (around 200 ng L⁻¹ and hardly detected, respectively). The antibiotics sulfamethoxazole (median 13.0 ng L⁻¹) and trimethoprim (median 61.5 ng L⁻¹), and the other pharmaceutical compounds (diclofenac and bezafibrate, with median 99.9 and 94.4 ng L⁻¹, respectively) were found in lower concentrations when compared with reports in the literature, which might indicate a lower consumption of such drugs in Brazil. The UASB reactors were inefficient in the removal of bisphenol A, and led to an increased concentration of nonylphenol in the effluent. The anaerobic reactors were also inefficient in the removal of diclofenac, and led to a partial removal of bezafibrate; whereas, for sulfamethoxazole there seemed to be a direct relationship between the HRT and removal efficiencies. For trimethoprim the sludge retention time (SRT) seemed to play an important role, although it was only partially removed in the UASB reactors.

Efeito do tipo de óleo de soja na composiçäo em ácidos graxos da carcaça de frangos de corte / Effect of different soybean oils on fatty acids composition of broiler carcass

Para avaliar o efeito de diferentes tipos de óleo de soja na composiçäo em ácidos graxos da carcaça, foram utilizados 128 frangos (64 machos e 64 fêmeas) da linhagem Hubbard. O delineamento experimental foi inteiramente ao acaso, com quatro repetiçöes, e os tratamentos foram constituídos de um fatorial 4 I 2 (quatro dietas e dois sexos). As quatro dietas foram formuladas da seguinte forma: A- sem adiçäo de óleo (controle); B -com óleo de soja refinado; C- com óleo de soja degomado e D- com borra acidulada. As dietas foram isocalóricas e isonutritivas. Aos 45 dias de idade os frangos foram abatidos, eviscerados, congelados e moídos para posterior análise de extrato etéreo e composiçäo em ácidos graxos. Os machos que receberam dietas sem adiçäo de óleo depositaram (P<0,05) mais ácido mirístico do que as fêmeas. As aves que receberam dieta com óleo refinado depositaram (P<0,05) mais ácido esteárico na carcaça do que as submetidas às demais dietas. As carcaças das aves que receberam dietas com adiçäo de óleo apresentaram menor teor (P<0,05) de ácido graxo palmitoléico do que as que näo receberam suplementaçäo com óleo. As carcaças das aves que receberam dietas controle e com adiçäo de borra acidulada apresentaram maior teor de ácido oléico quando comparadas com as que receberam os óleos refinado e degomado. Os resultados demonstraram que o óleo de soja refinado e o óleo de soja degomado aumentaram o teor de ácido graxo linoléico na gordura da carcaça de frango, tornando-a mais insaturada. Os resultados foram semelhantes quanto ao sexo