Decolorization of practical textile industry effluents by white rot fungus Coriolus versicolor IBL-04

Textile industry discharges a vast amount of unused synthetic dyes in effluents. The discharge of these effluents into rivers and lakes leads to a reduction in sunlight penetration in natural water bodies, which, in turn, decreases both photosynthetic activity and dissolved oxygen concentration rendering it toxic to living beings. This paper describes the decolorization potential of a local white rot fungus, Coriolus versicolor IBL-04 for practical industrial effluents collected from five different textile industries of Faisalabad, Pakistan. Screening of C. versicolor IBL-04 on five effluents showed best decolorization results (36.3%) for Arzoo Textile Industry (ART) effluent in 6 days followed by Crescent Textile Industry (CRT), Itmad Textile Industry (ITT), Megna Textile Industry (MGT) and Ayesha Textile Industry (AST) effluents. Optimization of different process parameters for ART effluent decolorization by C. versicolor IBL-04 showed that manganese peroxidase (MnP) (486 U/mL) was the lignolytic enzyme present in the culture filtrates with undetectable lignin peroxidase (LiP) and laccase. The MnP synthesis and effluent decolorization could be enhanced to 725 U/mL and 84.4%, respectively, with a significant time reduction to 3 days by optimizing pH and temperature and using 1% starch as a supplementary carbon source.     

From natural products discovery to commercialization: a success story

In order for a natural product to become a commercial reality, laboratory improvement of its production process is a necessity since titers produced by wild strains could never compete with the power of synthetic chemistry. Strain improvement by mutagenesis has been a major success. It has mainly been carried out by “brute force” screening or selection, but modern genetic technologies have entered the scene in recent years. For every new strain developed genetically, there is further opportunity to raise titers by medium modifications. Of major interest has been the nutritional control by induction, as well as inhibition and repression by sources of carbon, nitrogen, phosphate and end products. Both strain improvement and nutritional modification contribute to the new process, which is then scaled up by biochemical engineers into pilot scale and later into factory size fermentors.     

Meningitis,pathogenicity near criticality: the epidemiology of meningococcal disease as a model for accidental pathogens

We formulate and analyse a model for infectious diseases transmitted by asymptomatic carriers finding, that if harmless and pathogenic strains of the infected agent compete, frequent outbreaks of the pathogenic strains can occur. A counterintuitively high number of clustered outbreaks at low pathogenicity in our model compares well with observations in diseases with severe and often fatal results for the host, as for example in meningitis. These clustered outbreaks can be described by the typical scaling behaviour around criticality. The epidemic model is a susceptible-infected-recovered system (SIR) for the harmless infective agent, acting as a background to a mutant strain Y which occasionally creates severely affected hosts X. The full system of SIRYX is described in the master equation framework, confirming limiting assumptions about a reduced YX-system with the SIR-system in stationarity. In this limiting case we can analytically show convergence to power law scaling typical for critical states, as well as the divergence of the variance of outbreaks near criticality. These large fluctuations of outbreaks of accidental pathogens as mutants of otherwise harmless commensal organisms is the challenging new feature of our model for future epidemiology of diseases like meningococcal disease.     

Evaluation of individual protein errors in silver-stained two-dimensional gels

The relationship between spot volume and variation for all protein spots observed on large format 2D gels when utilising silver stain technology and a model system based on mammalian NSO cell extracts is reported. By running multiple gels we have shown that the reproducibility of data generated in this way is dependent on individual protein spot volumes, which in turn are directly correlated with the coefficient of variation. The coefficients of variation across all observed protein spots were highest for low abundant proteins which are the primary contributors to process error, and lowest for more abundant proteins. Using the relationship between spot volume and coefficient of variation we show it is necessary to calculate variation for individual protein spot volumes. The inherent limitations of silver staining therefore mean that errors in individual protein spot volumes must be considered when assessing significant changes in protein spot volume and not global error.     

A multicriteria approach to reserve selection: addressing long-term biodiversity maintenance

Existing complementarity-based reserve selection techniquesconcerned with maximal biodiversity representation within minimum landarea do not necessarily ensure the long-term maintenance ofbiodiversity. These approaches often ignore the maintenance of naturalprocesses, turnover of feature diversity and the need to minimisethreats within conservation areas. We address these three emergentissues in the identification of potential avian conservation areas inthe Northern Province of South Africa, by combining ordination andspatial autocorrelation analyses, as well as land transformation datainto complementarity-based reserve selection techniques. Existingconservation areas are biased and inefficient and complementarity-basedmethods do little to correct this skew. The inclusion of speciesassemblage structure as well as the underlying environmental gradientsensures a conservation area network that strives to maintain bothbiodiversity pattern and process. Spatial autocorrelation analysisallows for the identification of areas with high diversity,important areas for the long-term maintenance of biodiversity. Theinclusion of land transformation data leads to viable conservation areanetworks and highlights areas of potential conflict between biodiversityconservation interests and human land-use issues. These combinedimprovements on complementarity-based reserve selection techniques bringus a step closer to ensuring the long-term maintenance of biodiversitywithin conservation areas in the northern province.     

Design of a microfluidic mixer channel: First steps into creating a fluorescent dye-based biosensor for mAb aggregate detection

A major challenge in the transition to continuous biomanufacturing is the lack of process analytical technology (PAT) tools which are able to collect real-time information on the process and elicit a response to facilitate control. One of the critical quality attributes (CQAs) of interest during monoclonal antibodies production is aggregate formation. The development of a real-time PAT tool to monitor aggregate formation is then crucial to have immediate feedback and process control. Miniaturized sensors placed after each unit operation can be a powerful solution to speed up an analytical measurement due to their characteristic short reaction time. In this work, a micromixer structure capable of mixing two streams is presented, to be employed in the detection of mAb aggregates using fluorescent dyes. Computational fluid dynamics (CFD) simulations were used to compare the mixing performance of a series of the proposed designs. A final design of a zigzag microchannel with 45° angle was reached and this structure was subsequently fabricated and experimentally validated with colour dyes and, later, with a FITC-IgG molecule. The designed zigzag micromixer presents a mixing index of around 90%, obtained in less than 30 seconds. Therefore, a micromixer channel capable of a fast and efficient mixing is hereby demonstrated, to be used as a real-time PAT tool for a fluorescence based detection of protein aggregation.