ABSTRACT
Laccases are oxidoreductase enzymes that have the ability to oxidize phenolic substrates. Its biotechnological potential has been greatly explored in many areas as biotechnology industry, bioremediation of dyes, food industry and environmental microbiology. The aim of this study was maximize the laccase production by Pleurotus pulmonarius (Fr.) Quélet in solid-state fermentation (SSF) using orange waste as substrate. After optimization the capability of the crude laccase to decolorize dyes was analyzed. The fermentation medium in the solid-state was optimized by applying a factorial design. After statistics optimization, laccase activity increased two times. The laccase activity appears to be correlated with the ability of crude extract to decolorize some industrial dyes. The optimized laccase was characterized with respect to optimum pH, influence of temperature and salts. Our results demonstrate that P. pulmonarius was an efficient producer of an important industrial enzyme, laccase, in a cheap solid-state system using orange waste as substrate.
Subject(s)
Citrus sinensis/microbiology , Citrus sinensis/chemistry , Laccase , PleurotusABSTRACT
RESUMOO processo de oxidação avançada do tipo reação Fenton (Fe2+/H2O2) foi estudado neste trabalho para descoloração de dois efluentes sintéticos, contendo os corantes Azul de Metileno (AM) e Rodamina B (RB). Experimentalmente, soluções em concentração de 10 mg L-1 dos corantes foram submetidas a diferentes dosagens de agente oxidante (H2O2) e catalisador (Fe2+) em uma temperatura de 27 °C e pH 3. Os resultados obtidos apresentaram altos níveis de remoção de cor, com eficiência da ordem de 96% para o AM e 86% no RB. Os dados mostraram bom ajuste ao modelo cinético. O monitoramento do espectro de absorção dos corantes mostrou uma diminuição da amplitude dos picos relacionados aos grupos cromóforos em ambos compostos, corroborando com os níveis de eficiência alcançados. A análise de remoção de matéria orgânica em termos de Demanda Química de Oxigênio (DQO) não acompanhou a mesma taxa de decréscimo de descoloração, obtendo-se reduções de 40,9% para o AM e 25,5% para o RB.
ABSTRACTThe process of advanced oxidation by Fenton reaction (Fe2+/H2O2) was studied in this work for decolorization of two synthetic effluents, containing the dyes Methylene Blue (MB) and Rhodamine B (RB). Experimentally, solutions at concentrations of 10 mg L-1 of the dyes were exposed to different concentrations of the oxidizing agent (H2O2) and catalyst (Fe2+) at a temperature of 27 °C and pH 3. The results showed high levels of color removal, with efficiency of 96% for MB and 86% RB. The data showed good adjustment to the kinetic model. The monitoring of the absorption spectrum of the dyes showed a reduction in amplitude of the peaks related to the chromophoric groups in both compounds, confirming the levels of efficiency achieved. The analysis of removal of organic matter in terms of Chemical Oxygen Demand (COD) did not follow the same rate of decrease of decoloration, resulting in reductions of 40.9% for MB and 25.5% for the RB.
ABSTRACT
Objective To study the optimum decoloration technological conditions of crude polysaccharides from Cordyceps militaris Link. (PCM) by macroporous resin. Methods With the decolorization rate and retention rate of PCM as indexes, static adsorption factor experiment was used for the optimization of seven kinds of macroporous resin. And then the optimum conditions of decolorization of PCM were investigated by the static/dynamaic adsorption single-factor experiments. Results D941 macroporous resin is the best. The optimum decoloration technological conditions were as follows:initial concentration of the sample was 50 mg/mL, pH value was 5.5, operating temperature was 45℃, the flow rate of dynamaic adsorption was 2.5 BV/h, and the sample solution volume was 5 bed volume per hour. Under the optimal conditions, decolorization rate and retention rate of PCM were ( 93.9 ± 3.4) % and (91.7 ± 2.2) %, respectively. Conclusion The resin D941 is suitable for the decoloration of PCM. The optimized method is feasible and reliable, having the prospects for popularizing.
ABSTRACT
Objective To study the effect of macroporous adsorptive resins on the decoloration technology ofLonicera japonica Thunb. polysaccharides(FLP).Methods The effects of 6 kinds of macroporous adsorptive resins i.e. HPD-400A, AB-8, HPD-750, HPD-100, D3520, D301T, S8 on the decolorization technology ofLonicera japonica Thunb. polysaccharides were compared with single factor test in terms of temperature, polysaccharide concentration, pH, adsorption flow, and eluant.Results The decolorization rate and polysaccharide retention rate of S8 were optimal. The best decoloration conditions were as follows: temperature of 40℃, polysaccharide concentration of 5 mg/ml, pH value of 6, flow rate of 1 ml/min, distilled water with pH=6 as eluant. The adsorption rate was 83.2%,and polysaccharide retention rate was 72.1%.Conclusion High decolorization ratio and the high retention rate ofLonicera japonica Thunb. could be obtained by means of decoloration with S8 macroporous adsorptive resins..
ABSTRACT
O uso de fungos na descoloração de corantes com métodos economicamente viáveis de produção de água bacteriologicamente segura há muito vem sendo descrito por diversos autores. Este trabalho teve por objetivo investigar a eficiência da remoção de corante artificial FD&C azul no 2 Indigotina, com uso do fungo de degradação branca Trametes versicolor em combinação com a filtração lenta. Para a realização dos trabalhos, foram instalados dois protótipos de filtros lentos denominados FL-A e FL-B - no sobrenadante do filtro FL-A foi inoculado o referido fungo, e o filtro FL-B foi utilizado como controle (sem inoculação do microrganismo). O melhor percentual de remoção do corante pelo fungo Trametes versicolor em combinação com a filtração lenta foi de 44,74% 24 horas após a atividade máxima registrada de lacase. Os resultados mostraram que a filtração lenta combinada com o tratamento com o fungo T. versicolor não apresenta grande potencial para remoção de cor em 21 dias de tratamento, visto que os produtos microbianos gerados interferem no processo de filtração, diminuindo a eficiência do processo físico. Entretanto, restringindo o tempo de tratamento a 24 horas após a atividade enzimática máxima, o tratamento combinado apresentou boa eficiência.
The use of fungi in the decolorization of dyes with economically viable methods of producing bacteriologically safe water has long been described by several authors. This study aimed to investigate the removal efficiency of artificial coloring FD&C Blue no 2 Indigo, using the degradation white fungus Trametes versicolor in combination with slow sand filtration. Two prototype filters slowly termed FL-A and FL-B were installed - the supernatant water of filter FL-A was inoculated with the fungus, while filter FL-B was used as control. The best percentage of dye removal by the fungus Trametes versicolor in combination with the slow sand filtration was 44.74% achieved 24 hours after the maximum laccase activity. The results show that the combination of the fungus T. versicolor with slow sand filtration treatment presents no great potential for color removal at 21 days of treatment, whereas microbial products generated interfere with the filtration process, lowering the efficiency of the physical process. However, with the restriction of the handling time into 24 hours after the maximum enzymatic activity, combined treatment showed good efficiency.