In this work an unmanned aerial vehicle (UAV) was adapted to be used as an environmental tool to collect water samples of sea, estuary, and mangrove for further analysis by gas chromatography with a mass detector (GC-MS). The sampling automated system was based on a microcontroller, a solenoid valve, and a peristaltic mini-pump that was coupled to a quadcopter UAV. The apparatus was properly calibrated to acquire 100 mL of environmental water at 4.6 min. After, the concentration of BTEX (benzene, toluene, ethylbenzene, and o, m, p-xylenes) was analyzed in laboratory using GC-MS and the BTEX concentration ranged from 0.3 to 5.0 µg L-1 with a recovery from 83.9 to 118% with a relative standard deviation lower than 7.0%. Tests of cross-contamination were performed by simultaneous sampling and laboratory blank was carried out and no contamination was found for BTEX analysis. Based on the results, the adapted UAV presented a very useful ability to collect samples in difficult access areas such as mangroves, points between rocks, corals reefs, without health risk and without impacting the fragile ecosystem being an interesting tool for environmental purposes.

Background Streptomyces sp. DPUA 1576 from Amazon lichens was studied to protease and fibrinolytic production. A 2² factorial experimental design was applied to optimize its protease enzyme production using two independent variables, namely soybean flour and glucose concentrations. Results The optimal conditions to obtain high protease production (83.42 U/mL) were 1.26% soybean flour and 1.23% glucose concentration. A polynomial model was fitted to correlate the relationship between the two variables and protease activity. In relation to fibrinolytic activity, the highest activity of 706.5 mm² was obtained at 1.7% soybean flour and 1.0% glucose concentration, which was 33% higher than plasmin. Fibrinolytic production was not optimized in the studied conditions. Conclusions These results show that the optimization of the culture medium can enhance protease production, thus becoming a good process for further research. In addition, Streptomyces sp. DPUA 1576, isolated from Amazon lichens, might be a potential strain for fibrinolytic protease production.

The selection of new microorganisms able to produce antimicrobial compounds is hoped for to reduce their production costs and the side effects caused by synthetic drugs. Clavulanic acid is a β-lactam antibiotic produced by submerged culture, which is widely used in medicine as a powerful inhibitor of β-lactamases, enzymes produced by bacteria resistant to antibiotics such penicillin and cephalosporin. The purpose of this work was to select the best clavulanic acid producer among strains of Streptomyces belonging to the Microorganism Collection of the Department of Antibiotics of the Federal University of Pernambuco (DAUFPE). Initially, the strains were studied for their capacity to inhibit the action of β-lactamases produced by Klebsiella aerogenes ATCC 15380. From these results, five strains were selected to investigate the batch kinetics of growth and clavulanic acid production in submerged culture carried out in flasks. The results were compared with the ones obtained by Streptomyces clavuligerus ATCC 27064 selected as a control strain. The best clavulanic acid producer was Streptomyces DAUFPE 3060, molecularly identified as Streptomyces variabilis, which increased the clavulanic acid production by 28% compared to the control strain. This work contributes to the enlargement of knowledge on new Streptomyces wild strains able to produce clavulanic acid by submerged culture.

Clavulanic acid is a β-lactam antibiotic which has a potent β-lactamase inhibiting activity. In order to optimize its production by the new isolate Streptomyces DAUFPE 3060, the influence of two independent variables, temperature and soybean flour concentration, on clavulanic acid and biomass concentrations was investigated in 250 mL-Erlenmeyers according to a 2² central composite design. To this purpose, temperature and soybean flour (SF) concentration were varied in the ranges 26-34°C and 10-50 g/L, respectively, and the results evaluated utilizing the Response Surface Methodology. The experimental maximum production of clavulanic acid (629 mg/L) was obtained at 32°C and 40 g/L SF after 48 h, while the maximum biomass concentration (3.9 g/L) at 30°C and 50 g/L soybean flour, respectively. These values are satisfactorily close to those (640 mg/L and 3.75 g/L, respectively) predicted by the model, thereby demonstrating the validity of the mathematical approach adopted in this study.

Um novo composto fluorescente de microcistina-LR marcado com criptato de térbio foi obtido pela conjugação inicial da microcistina-LR com aminoetanotiol, seguido pela reação com o grupo éster do criptato de térbio. A formação do produto foi acompanhada por cromatografia líquida de alta eficiência (CLAE) em 238 nm e 310 nm. A presença de microcistina-LR na molécula marcada foi confirmada através de ensaio com enzima ligada a imunoabsorvente (ELISA) e por reação protéica com ácido bicincônico. O espectro de luminescência do criptato e da molécula conjugada também foram confirmados.

A new fluorescent labeled compound of microcystin-LR with terbium cryptate was obtained by initial conjugation of microcystins-LR with aminoethanethiol followed by the reaction with the ester group of terbium cryptate. The product formation was followed by high performance liquid chromatography (HPLC) at 238 nm and 310 nm. The presence of microcystin-LR in the labeled molecule was confirmed by enzyme linked immunosorbent assay ELISA and by protein reaction with bicinhonic acid. Luminescence spectra of cryptate and the conjugated molecule were carried through as well.

Foi avaliado o efeito de diferentes fontes de carbono na atividade de pectinesterease, endo - e exo-polygalacturonase de Aspergillus japonicus 586, em meio líquido (soluções de Manachini) suplementado com diferentes concentrações de substratos. O meio de cultura foi inoculado com 5 x 10(6) esporos/ml e mantido sob agitação (140 rpm), a 30°C, durante 120 h. A avaliação das enzimas foi realizada a cada 24 h após filtração. O extrato cru de A. japonicus 586 mostrou que as melhores atividades enzimáticas foram obtidas na presença de 0,5% pectina (pectinestarease), 0,2% pectina e 0,2% glicerol (endopoligalacturonase) e 0,5% pectina associada a 0,5% glicose (exopoligalacturonase). Diferentes concentrações de fontes de carbono, isoladas ou associadas afetaram significativamente as atividades de polinesterase, endo- e exopoligalacturonase. Quando adicionado pectina, glicose e sacarose em altas concentrações, ao meio de cultura, observou-se um efeito de repressão de todas as enzimas analisadas.

The effect of different carbon sources on the pectinesterases, endo- and exo-polygalacturonase activities from Aspergillus japonicus 586 was evaluated in liquid media (Manachini solutions) supplemented with different substrate concentrations. The culture medium was inoculated with 5.10(6) spores/ml and mantained under agitation (140 rpm), at 30°C, during 122 h. The enzyme evaluation was carried out 24 h after filtration. The crude extract from A. japonicus 586 indicated that the best enzymatic activities were afforded in the presence of 0.5% pectin (pectinesterease), 0.2% pectin and 0.2% glycerol (endopolygalacturonase), and 0.5% pectin associated to 0.5% glucose (exopolygalacturonase). Carbon sources concentration, isolated or associated, significantly affects the pectinesterase, and endo- and exopolygalacturonase activities. Pectin, glucose and saccharose, when added to the culture medium in high concentrations, exhibited a repression effect on all the analyzed enzymes.