Enzymes are powerful tools that help sustain a clean environment in several ways. They are utilized for environmental purposes in a number of industries including agro-food, oil, animal feed, detergent, pulp and paper, textile, leather, petroleum, and specialty chemical and biochemical industry. Enzymes also help to maintain an unpolluted environment through their use in waste management. Recombinant DNA technology, protein engineering, and rational enzyme design are the emerging areas of research pertaining to environmental applications of enzymes. The future will also see the employment of various technologies including gene shuffling, high throughput screening, and nanotechnology. This article presents an overview of the enzymatic applications in pollution control and the promising research avenues in this area.

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Here we report the successful implementation of the Plackett-Burman multifactorial design to screen the limiting components for growth and subsequent use of the response surface methodology (RSM) to design a medium that supported exponential growth of the aggregated morphology of the shipworm bacterium, Teredinobacter turnirae. The results obtained with the help of Plackett-Burman design indicated limitations of three components in the growth medium, MnCl2.4H2O, Na2CO3, and K2HPO4. The concentrations of these three components were further optimized using RSM. By increasing the concentrations of the above-mentioned components by 4-fold, 12-fold, and 12-fold, respectively, it became possible to achieve exponential growth of the culture.

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O presente trabalho foi conduzido no laboratório de sementes e casa de vegetação da UNIOESTE -- Câmpus de Marechal Cândido Rondon -- PR, com o objetivo de avaliar o efeito de diferentes concentrações de ácido giberélico (GA3) na germinação de sementes e na emergência de plântulas de fruta-do-conde (Annona squamosa L.), em diferentes recipientes, visando à produção de mudas. O experimento foi instalado em delineamento experimental inteiramente casualizado. Os tratamentos foram compostos pela embebição das sementes em sete concentrações de ácido giberélico (0; 50; 100; 250; 500; 750 e 1000 mg.L-1), por 5 horas, com 4 repetições de 25 sementes. No campo, os tratamentos foram constituídos das sete concentrações de GA3 e dois tipos de embalagens (bandejas de isopor e sacolas de polietileno), com 4 repetições de 25 sementes. As avaliações do laboratório constaram de porcentagem total de sementes germinadas, dormentes e mortas; porcentagem total de plântulas normais e anormais, e índice de velocidade de germinação (IVG) e do campo, pela porcentagem total de plântulas emergidas; índice de velocidade de emergência de plântulas (IVE); altura de plântulas e número de folhas. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey, a 5% de probabilidade. Verificou-se que o GA3 promoveu o incremento na germinação de sementes de Annona squamosa e que as sacolas de polietileno foram mais adequadas do que as bandejas no desenvolvimento das plântulas na fase inicial.

Single and multicomponent batch adsorption kinetics were obtained for deamidated mAb variants on two commercial cation exchangers, one with an open macroporous structure--UNOsphere S--and the other with charged dextran grafts--Capto S. The adsorption kinetics for the macroporous matrix was found to be controlled largely by pore diffusion. The effective diffusivity estimated from single component data was a fraction of the mAb free solution diffusivity, and its value could be used to accurately predict the adsorption kinetics for two- and three-component systems. In this case, when two or more variants were adsorbed simultaneously, both experimental and predicted results showed a temporary overshoot of the amount adsorbed above the equilibrium value for the more deamidated variant followed by a gradual approach to equilibrium. Adsorption rates on the dextran grafted material were much faster than those observed for the macroporous matrix for both single component and simultaneous adsorption cases. In this case, no significant overshoot was observed for the more deamidated forms. The Capto S adsorption kinetics could be described well by a diffusion model with an adsorbed phase driving force for single component adsorption and for the simultaneous adsorption of multiple variants. However, this model failed to predict the adsorption kinetics when more deamidated forms pre-adsorbed on the resin were displaced by less deamidated ones. In this case, the kinetics of the displacement process was much slower indicating that the pre-adsorbed components severely hindered transport of the more strongly bound variants. Overall, the results indicate that despite the lower capacity, the macroporous resin may be more efficient in process applications where displacement of one variant by another takes place as a result of the faster and more predictable kinetics.