Tratamento de compostos orgânicos odoríferos tóxicos por biorreatores / Treatment of odorous toxic organic compounds by bioreactor

Introdução É importante o desenvolvimento de sistemas de controle de poluição do ar que sejam eficientes, além de aplicáveis à condição nacional e pra proteção da saúde humana, uma vez que os compostos do grupo BTEX são tóxicos. Objetivo - Avaliar o desempenho de sistema de tratamento biológico para vapores de BTEX e investigar as melhores condições de operação para os critérios de projeto adotados. Métodos. Trata-se de trabalho experimental com utilização de unidade piloto constituída de coluna de vidro (diâmetro interno de 80 mm e altura total de 1,2 m) tendo no seu interior um meio filtrante composto vegetal e anéis de Pall - que serviram de suporte para os microrganismos e onde se realizou a biodegradação. Foram monitorados parâmetros como temperatura, perda de carga, vazão, concentração dos gases na entrada e na saída, que constituíram a base para desenvolver intervenções e melhorar seu desempenho. A análise dos gases foi feita por fotoionização (PID) em aparelho portátil. Conclusões - Conclui-se que é viável o tratamento biológico para remoção do BTEX de efluentes gasosos, nas condições operacionais adotadas, com eficiência máxima de remoção em torno de 90 por cento . A máxima eficiência foi obtida para tempo de retenção de 2,4 min., carga superficial do gás de 11,9 m3/m2xh, carga mássica no leito de 67 g/m3xh e capacidade de eliminação de 4 g/m3xh. O uso de anéis de Pall misturados ao composto evitou que valores elevados de perda de carga. Foi relevante a participação da adsorção. A utilização de composto mostrou-se viável como alternativa para a biodegradação do BTEX, fortalecendo seu uso com essa prática ambiental.

Investigation of fatty acid esters to replace isopropyl myristate in the sterility test for ophthalmic ointments.

Several pharmacopoeias recommend the membrane filtration method for the sterility test of ophthalmic ointments. Isopropyl myristate, a fatty acid ester that exhibits high toxicity mainly against Gram-negative microorganisms, is indicated as a solvent for ointments. In this study, six fatty acid esters (diethyl adipate, diisopropyl adipate, ethyl laurate, ethyl myristate, methyl caprylate and isopropyl palmitate) were evaluated as solvents to replace isopropyl myristate in the sterility test for ophthalmic ointments. The logarithm of the partition coefficient (logP) of the fatty acid esters was calculated from the sum of the substituent hydrophobicity constants (pi) of the functional groups present in their molecules. The ability of the solvents to dissolve an ophthalmic ointment base was investigated. The D-value method was used to assess the antimicrobial activity of isopropyl palmitate, ethyl myristate, ethyl laurate and isopropyl myristate against Pseudomonas aeruginosa. Isopropyl palmitate was the least toxic solvent to this microorganism, since it had the highest D-value (171.1 min). No significant difference was observed between the D-values of ethyl myristate (89.4 min) and isopropyl myristate (92.5 min). Ethyl laurate exhibited the lowest D-value (27.2 min). Using gas chromatography coupled to mass spectrometry, other fatty acid esters were detected as the predominant impurities in the solvents, as well as acid contaminants in low or insignificant amounts.

Identification of bacteria in water for pharmaceutical use.

Different systems for the obtention of water used in Biopharmaceutical Industry were characterized from the bacteriological point of view. Determination of aerobic mesophilic microorganisms was performed; as well as the isolation of contaminant microorganisms for what the techniques of membrane filtration was used. For the identification of the more representative species there were made conventional biochemical tests and quick systems: API. The results show that water serving as tap water for purification systems fulfill with the microbiological requirements to this kind of water. All the isolated microorganisms were gram-negative bacteria characteristics of this environment: Pseudomonas putida, Xanthomonas maltophilia, Aeromonas salmonicida ssp. salmonicida, Flavimonas coryzihabitans and Acinetobacter iwoffi. The ultrafiltration and distillation tested systems fulfill with the established microbiological limits, except for deionization and distilled water storing systems. The isolation showed that approximately the 76.9% were of Gram-negative bacteria, the 14.6% of Gram-positive cocci and the 8.5% Gram-positive sporulated bacilli. The most representative genus of purified water were: Pseudomonas, with the higher percent of incidence, Staphylococcus, Bacillus, Flavobacterium, Sphingomonas, Aeromonas and Agrobacterium.