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In this work were studied the pH, thermal, and storage stability of free and immobilized laccases. Enzymes were produced by Pleurotus ostreatus on potato dextrose (PD) broth and potato dextrose modified (PDM) broth, and immobilized using Luffa cylindrica fibers as support. Both free and immobilized enzymes were assessed on their respective enzymatic activities and for 17α-ethinylestradiol (EE2) degradation. The optimum pH conditions concerning laccase activity ranged from 3.6 to 4.6, while temperature ranged between 30 °C and 50 °C for both free and immobilized enzyme. Laccase produced using PD broth presented greater storage stability and thermal stability than that of PDM. Best EE2 removals were of 79.22% and 75.00% for the free and immobilized enzymes, respectively. Removal rates were assessed during 8 h at pH 5. The removal of 17α-ethinylestradiol was stabilized in the fourth cycle of use. Results imply that immobilization promoted stability towards pH and temperature variations, although media played a decisive role in the enzymatic activity. Both free and immobilized laccases of P. ostreatus were able to degrade EE2, whereas immobilized laccase in PDM medium presented possible reuse applicability, albeit removal was not optimal when compared to other reports.

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Currently, the quality of the water consumed by the population, and also the water used for both leisure and therapeutic bathing, are known. In the city of Poços de Caldas, Minas Gerais, Brazil, the population has two sources of sulfurous thermal water, with free access for various purposes, including drinking. Since 1882, the system has retained the same structural characteristics, and at this time, there appears to be a risk of anthropogenic contamination due to population increase near the springs. The aim of this study was to evaluate the water quality of the sulfurous hot springs distributed in Pedro Botelho fountain, located in Thermas Antônio Carlos, and Monkey fountain, located in Mario Mourao bathhouse, for microbiological and bacteriological components, physical and chemical composition, and radionuclides for a period of 12 months and to compare their quality with Brazilian water quality laws. The results showed that all the values are within the prescribed water quality parameters, except fluoride and sodium, whose levels are above those permitted by law. Excess fluoride in consumed water can cause dental fluorosis and skeletal fluorosis. As for sodium, which exceeded the permissible limits by 20 to 25 %, it can be detrimental to hypertensive individuals. An important fact to consider is that water from sulfurous hot springs cannot be consumed without medical supervision because its chemical characteristics may cause damage to health, and it should only be used as medicinal mineral water.

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Este trabalho teve como objetivo fazer um levantamento sucinto da presença de resíduos de medicamentos no ambiente aquático e em estações de tratamento de esgotos, bem como discutir a necessidade iminente de ações que possam auxiliar nesse tipo de contaminação ao reduzir as emissões, orientar o gerenciamento adequado de resíduos de farmácia e de descarte em domicílios. Além disso, foram apresentados resultados de ensaios ecotoxicológicos empregados na avaliação de efeitos da fluoxetina em Vibrio fischeri e em H. azteca, organismos aquáticos frequentemente expostos a contaminantes ambientais. Dos resultados obtidos, observou-se que a partir de 0,3 mg.l-1 de cloridrato de fluoxetina ocorreu mortalidade em H. azteca, enquanto que a inibição de fotoluminescência em Vibrio fischeri foi obtida a partir de 30 mg.l-1. Nesse último caso, os menores valores de CE50 demonstraram toxicidade mais elevada nos ensaios com o produto genérico.

The objective of this paper was to review data on residues of medical products in aquatic environments and at waste water treatment plants. Secondarily the paper presents a discussion about the need for a good management of drugs residues and effluents generated by this sector. Bringing the evidences of environmental possible damages reported by ecotoxicity data on the effects of fluoxetine to Vibrio fischeri and H. azteca, aquatic organisms daily exposed to environmental contaminants. From the results we observed that 0.3 mg.l-1 of fluoxetine hidrochloride induced lethality to H. azteca and 30 mg.l-1 reduced the luminescence of Vibrio fischeri. This assay evidenced higher toxicity when we used the “generic” product.

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The production of manganese peroxidase (MnP) from Bacillus pumilus and Paenibacillus sp. was studied under absence and presence of the inducers indulin AT, guayacol, veratryl alcohol, lignosulfonic acid and lignosulfonic acid desulfonated. Indulin AT increased the activity of B. pumilus MnP up to 31.66 U/L after 8 h, but no improve was observed for Paenibacillus sp., which reached maximum activity (12.22 U/L) after 20 h. Both MnPs produced by these microorganisms were purified in phenyl sepharose resin and the proteins from crude extracts were eluted in two fractions. However, only the first fraction of each extract exhibited MnP activities. Tests in different pH and temperature values, from pH 5.0 to pH 10.0 and 30 ºC to 60 ºC, respectively, were carried out with the purified MnP. The maximum activity reached for B. pumilus and Paenibacillus sp. MnPs were 4.3 U/L at pH 8.0 and 25 ºC and 11.74 U/L at pH 9.0 and 35 ºC, respectively. The molar masses determined by SDS-PAGE gel eletrophoresis were 25 kDa and 40 kDa, respectively, for the purified enzyme from B. pumilus and Paenibacillus sp.

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Bacillus pumilus and Paenibacillus sp. were applied on the paper mill effluent to investigate the colour remotion. Inocula were individually applied in effluent at pH 7.0, 9.0 and 11.0. The real colour and COD remotion after 48h at pH 9.0 were, respectively, 41.87% and 22.08% for B. pumilus treatment and 42.30% and 22.89% for Paenibacillus sp. Gel permeation chromatography was used to verify the molar masses of compounds in the non-treated and treated effluent, showing a decrease in the compounds responsible for the paper mill effluent colour.

Bacillus pumilus e Paenibacillus sp. foram aplicados separadamente no efluente da indústria papeleira a pH 7,0, 9,0 e 11,0, para verificação da remoção da cor e da DQO. As remoções da cor real e DQO após 48h a pH 9,0 foram, respectivamente, de 41,87% e 22,08% após o tratamento com B. pumilus e 42,30% e 22,89% após tratamento com Paenibacillus sp. As massas molares dos compostos presentes no efluente não tratado e tratado foram determinadas por cromatografia de permeação em gel. O emprego dos microrganismos reduziu os compostos responsáveis pela cor do efluente da indústria papeleira.

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Bacillus pumilus and Paenibacillus sp. were applied on the paper mill effluent to investigate the colour remotion. Inocula were individually applied in effluent at pH 7.0, 9.0 and 11.0. The real colour and COD remotion after 48h at pH 9.0 were, respectively, 41.87% and 22.08% for B. pumilus treatment and 42.30% and 22.89% for Paenibacillus sp. Gel permeation chromatography was used to verify the molar masses of compounds in the non-treated and treated effluent, showing a decrease in the compounds responsible for the paper mill effluent colour.

RESUMO

The production of manganese peroxidase (MnP) from Bacillus pumilus and Paenibacillus sp. was studied under absence and presence of the inducers indulin AT, guayacol, veratryl alcohol, lignosulfonic acid and lignosulfonic acid desulfonated. Indulin AT increased the activity of B. pumilus MnP up to 31.66 U/L after 8 h, but no improve was observed for Paenibacillus sp., which reached maximum activity (12.22 U/L) after 20 h. Both MnPs produced by these microorganisms were purified in phenyl sepharose resin and the proteins from crude extracts were eluted in two fractions. However, only the first fraction of each extract exhibited MnP activities. Tests in different pH and temperature values, from pH 5.0 to pH 10.0 and 30 °C to 60 °C, respectively, were carried out with the purified MnP. The maximum activity reached for B. pumilus and Paenibacillus sp. MnPs were 4.3 U/L at pH 8.0 and 25 °C and 11.74 U/L at pH 9.0 and 35 °C, respectively. The molar masses determined by SDS-PAGE gel eletrophoresis were 25 kDa and 40 kDa, respectively, for the purified enzyme from B. pumilus and Paenibacillus sp.

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The main characteristic of biosurfactants is their property of reducing the superficial and interfacial tension between two immiscible liquids of different polarities. The main obstacle to the application of biosurfactants is the high production costs, the use of alternative substrates being indicated to solve this problem. This work report the production of biosurfactant by Bacillus subtilis LB5a on a pilot scale using cassava wastewater as the substrate, and the study of the parameters related to its production. The cassava wastewater was heated, centrifuged and poured into a 40-liter batch pilot bioreactor adapted for simultaneous foam collection during the fermentative process. The temperature was maintained at 35 degrees C, agitation at 150 rpm and aeration 0.38 vvm during the first 12 h, and 0.63 vvm for the rest of the process. Samples of liquid fermentate were collected at regular intervals for the analysis of total carbohydrates, reducing sugars, pH, CFU/mL count and superficial tension. The foam was centrifuged and the biosurfactant purified. The kinetic data of the process showed that both the microbial population, which reached a maximum after about 24 h, and the foam production of 10.6 L, peaked between 24 and 36 h, coinciding with the greatest production of biosurfactant. The yield of semi-purified surfactant in the foam was 2.4 g/L. The superficial tension of the medium was reduced from 51 to 27 mN/m and the critical micellar concentration was 11 mg/L, which, in principle, characterizes it as a good tensoactive agent. As a function of its composition and productivity, cassava wastewater was identified as a good substrate for the production of the biosurfactant.

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Agua residuária da indústria cítrica foi utilizada como objeto de estudo de biodegradação através de um sistema de lodo ativado por batelada. As análises realizadas por CG/EM mostraram que os compostos provenientes do óleo de laranja como o limoneno, foram resistentes a biodegradação. A avaliação microbiológica realizada no decorrer do período mostrou que o número e tipo de colônias bacterianas variaram de acordo com o tempo, e pode ser observada uma sucessão de microrganismos durante a biodegradação do efluente cítrico. O microrganismo identificado como LAB-9 (Pseudomonas struzieri) e LAB-7 (não identificado) prevaleceram durante todo o processo, sugerindo que estes são organismos importantes para remoção da matéria orgânica no processo ou são melhores adaptados ao tipo de água residuária. O sistema de lodo ativado foi eficiente na redução de DBO e DQO, alcançando valores de 79 e 78 por cento respectivamente, num período de 15 h de reação, com uma relação F/M 4:2.

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The extracellular productions of beta-xylanase, beta-xylosidase, beta-glucosidase, beta-mannanase, arabinosidase, alpha-glucuronidase, alpha-galactosidase and Fpase from Bacillus pumilus CBMAI 0008 were investigated with three different xylan sources as substrate. The enzymatic profiles on birchwood, Eucalyptus grandis and oat were studied at alkaline and acidic pH conditions. B. pumilus CBMAI 0008 grown on the three carbon sources produced mainly beta-xylanase. At pH 10, the levels of xylanase were 328, 160 and 136 U/ml, for birch, oat and E. grandis, respectively. beta-Mannanase production was induced on E. grandis (5 U/ml) and arabinofuranosidase on oat (5 U/ml). Although small quantities of alpha-glucuronidase had been produced at pH 10, activity at pH 4.8 was 1.5 U/ml, higher than observed for Aspergillus sp. in literature reports. Preliminary assays carried out on E. grandis kraft pulp from an industrial paper mill (RIPASA S.A. Celulose e Papel, Limeira, SP, Brazil) showed a reduction of 0.3% of chlorine use in the pulp treated with the enzymes, resulting in increased brightness, compared to conventional bleaching. The enzymes were more efficient if applied before the initial bleaching sequence, in a non-pre-oxygenated pulp.

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