Panorama da pesquisa sobre tratamento e reúso de efluentes da indústria de antibióticos / Overview of research on the treatment and reuse of effluents from the antibiotics industry

RESUMO Este trabalho realizou uma revisão integrativa de artigos científicos indexados entre 2007 e 2017 em diferentes bases de dados sobre o tratamento e o reúso de efluentes provenientes da indústria de antibióticos. Foram encontrados 31 artigos, sendo que somente 4 abordaram o reúso de efluente, e 1 utilizou um sistema de tratamento em escala real. A maior parte desses estudos foi realizado na Ásia, com destaque para a China. Observa-se que, no Brasil, que é um dos grandes produtores e consumidores de fármacos do mundo, esse tipo de pesquisa ainda é incipiente. Os processos mais encontrados foram os oxidativos avançados que mostraram maior eficiência na remoção de antibióticos, mas podem gerar subprodutos, o que pode representar um risco ainda maior dependendo da substância formada. Os processos biológicos devem ser primeiramente aclimatados aos antibióticos para não serem impactados, entretanto, a liberação desses micro-organismos resistentes no corpo receptor também apresenta um risco ambiental. Os sistemas integrados de membranas ao biológico também foram bem eficientes, mas atenta-se ao risco na destinação final dessas membranas que foram capazes de reter esses compostos. No geral, são necessários mais estudos sobre essa abordagem para reduzir os riscos no desenvolvimento de micro-organismos multirresistentes no meio ambiente.

ABSTRACT This work carried out an integrative review of scientific articles indexed between 2007 and 2017 in different databases on treatment and reuse of effluents from the antibiotic industry. Thirty-one articles were found and only four addressed effluent reuse, and one used a full-scale treatment system. Most of these studies were conducted in Asia, with emphasis on China. In Brazil, which is one of the largest producers and consumers of drugs in the world, this type of research is still incipient. The most commonly found processes were oxidative advanced processes that showed greater efficiency in removing antibiotics, but may generate by-products, which might pose an even greater risk depending on the substance formed. Biological processes must first be acclimated to antibiotics in order not to be impacted, however, the release of these resistant microorganisms into the water bodies also presents an environmental risk. Biological integrated membrane systems were also very efficient, but attention should be given to the risk in the final destination of these membranes that were able to retain those compounds. Overall, further studies on this approach are needed to reduce the risks of developing multi-resistant microorganisms in the environment.

Bioremediation of Industrial Effluent using Cyanobacterial Species: Phormidium mucicola and Anabaena aequalis

Different Industries discharge effluent in different water bodies, which is the only reason of pollution. The main objective of the present study was to investigate the biodegradation and biosorption capacity of some potential cyanobacterial species; Phormidium mucicola and Anabaena aequalis in Textile and Pharmaceutical industries, Mandideep, Bhopal Madhya Pradesh, India. Industrial effluents are contaminated with heavy metal. The effluents were subjected to biological treatment using axenic cyanobacterial strains as batch system for 7 days. Removal efficiencies of the different contaminants were evaluated and compared. Results confirmed the high efficiencies of the investigated species for the removal of the target contaminants which were species and contaminant-dependent. BOD and COD recorded 91.18 and 82.54% as maximum removal efficiencies achieved by Anabaena aequalis. The highest removal efficiencies of the total suspended solids recorded 53.23% achieved by Phormidium mucicola, while 41.61% was recorded as the highest TDS. Concerning the contaminant metals, Phormidium mucicola showed the highest biosorption capacity where 86.12 and 94.63% removal efficiencies were achieved for Zn and Cu, respectively. In conclusion, results of the study confirmed the advantageous potential of using the tested cyanobacterial species for the bioremediation of industrial effluent and clearly showed the quality improvement of the discharged effluent which in turn will eliminate or at least minimize the expected deterioration of the receiving environment.

Biosorption of Lead by Bacillus cereus Isolated from Industrial Effluents.

Aims: To study the biosorption of lead ions from solution using Bacillus cereus isolated from industrial effluents collected from Peenya industrial area, Bangalore, India and to determine the optimum conditions for biosorption. Study design: Experimental study. Place and Duration of Study: Department of Microbiology and Biotechnology, Bangalore University, Bangalore, Karnataka, India, between October 2008 and December 2009. Methodology: Sixty bacterial strains were isolated from industrial effluents collected from Peenya industrial area. Among the sixty isolates only six were selected for further investigation due to their high minimum inhibition concentration for lead. Lead biosorption studies were carried out for all the six isolates using atomic absorption spectrometry. The optimum conditions (temperature, pH and culture age) for biosorption were determined for the isolate showing highest lead biosorption. Results: The lead biosorption capability of all six isolates was studied at different concentrations of lead (100, 200, 300, 400 and 500 mg/l). The isolate 6 showed highest lead biosorption capability and was identified as Bacillus cereus. Studies on the control of environmental factors revealed that an optimum temperature of 30°C and pH 5, facilitates maximum biosorption of lead by 24hrs old culture of Bacillus cereus. Conclusion: Biosorption is an alternative to traditional physicochemical methods for removing toxic metals from wastewaters. The results of this study are discussed in the light of the biosorption capacity of Bacillus cereus that could be exploited in the bioremediation of lead.

Uptake and accumulation of potentially toxic metals (Zn, Cu and Pb) in soils and plants of Durgapur industrial belt.

Uptake and accumulation of metals in crops may cause possible health risks through food chain. A field survey was conducted to investigate the accumulation of potentially toxic metals contamination in soil and plants irrigated with complexed industrial effluents. Concentration of Zn, Cu and Pb was 205-255, 101-130, 118-177 μg g-1 in rhizosphere soils and 116-223, 57-102 and 63-95 μg g-1 d. wt. in root and 95-186, 44-75 and 27-58 μg g-1 d. wt. in shoot, respectively. The trend in Cu and Pb was in the order: soil> root> shoot>seed while in Zn it was soil>root>seed>shoot. Roots accumulated a larger fraction of soil Cu (70%)> Zn (67%)> Pb (54%). Bioaccumulation coefficient of soil to root ranged from 51-98 for Zn, 54-85 for Cu and 43-63 for Pb. Analysis of variance showed marginal change in bioaccumulation coefficient, noticed between plants (p>0.05) while it varied significantly (p<0.01) between tissues and metals. It increased from root to seed/fruit (root > shoot > seed/fruit) while decreased between metals from Zn to Pb (Zn> Cu>Pb). Out of the three, two Cu and Pb accumulated to phyotoxic levels while Zn was within threshold limit of phytotoxicity.

Uso de extrato de levedura como fonte de carbono e de mediadores redox, para a degradação anaeróbia de corante azo / Use of yeast extract as source of carbon and redox mediators for the anaerobic degradation of azo dyes

O trabalho investigou a influência do uso do extrato de levedura, fonte dos mediadores redox riboflavina e nicotinamida, na remoção de cor de solução de corante azo Drimaren Azul HF-RL em condições anaeróbias. O trabalho envolveu a execução de ensaios em batelada, em frascos-reatores mantidos a 25 ºC, incubados com o azo-corante e lodo anaeróbio na presença e ausência de fontes de carbono (extrato de levedura ou glicose) e de mediadores redox (riboflavina ou extrato de levedura). O monitoramento da variação temporal de cor, a demanda química de oxigênio (DQO) e ácidos graxos voláteis (AGV) mostraram que a adição de extrato de levedura (0,5 g/L) resultou em eficiências de remoção de cor de 80 a 85 por cento nas primeiras 24 horas de incubação, e que os produtos da degradação do azo-corante foram tóxicos para todo o consórcio anaeróbio, o que resultou em baixas eficiências de remoção de DQO na presença e ausência do extrato de levedura. Os resultados indicaram, ainda, que as eficiências de remoção de cor foram inferiores a 30 por cento na presença de apenas glicose (fonte de carbono) ou riboflavina (mediador redox), indicando que o extrato de levedura atuou simultaneamente como fonte de carbono e de mediadores redox.

This paper investigated the influence of using yeast extract, which is the source of redox mediators riboflavin and nicotinamide, in the decolorization of solutions containing the azo dye Drimaren Blue HF-RL in anaerobic conditions. It involved the incubation of serum bottles kept at 25 ºC and inoculated with the azo-dye, and anaerobic sludge in the presence and absence of carbon source (glucose or yeast extract) and redox mediators (riboflavin and yeast extract). The monitoring of color, chemical oxygen demand (COD) and volatile fatty acids (VFA) showed that the addition of yeast extract (0.5 g/L) resulted in 80 to 85 percent color removal in the first 24 hours of incubation; and that the metabolites of dye degradation were toxic to the anaerobic microorganisms, which led to low COD removal efficiencies either in the presence or absence of yeast extract. The results also showed that the efficiencies of color removal were below 30 percent in the presence of only glucose or riboflavin, indicating that the yeast extract acted simultaneously as source of carbon and redox mediators.