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This work introduces a novel modification to the in vitro experimental vesiculardevelopment of the parasite. Our findings showed that protoscoleces exposed toinsulin developed into microcysts in shorter times. Moreover, a tenfold incrementin the yield of microcysts per tube was observed. An improvement of the in vitroculture of E. granulosus metacestodes was achieved. On the basis of this axenicin vitro system, biochemical, molecular and chemotherapeutical studies of E.granulosus will be greatly facilitated. Fil: Elissondo, María Celina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología. Laboratorio de Zoonosis Parasitarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina Fil: Pensel, Patricia Eugenia. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología. Laboratorio de Zoonosis Parasitarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina Fil: Denegri, Guillermo Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología. Laboratorio de Zoonosis Parasitarias; Argentina

Scale-up of bioprocesses is hampered by open questions, mostly related to poor mixing and mass transfer limitations. Concentration gradients of substrate, carbon dioxide, and oxygen in time and space, especially in large-scale high-cell density fed-batch processes, are likely induced as the mixing time of the fermentor is usually longer than the relevant cellular reaction time. Cells in the fermentor are therefore repeatedly exposed to dynamic environments or perturbations. As a consequence, the heterogeneity in industrial practices often decreases either yield, titer, or productivity, or combinations thereof and increases by-product formation as compared to well-mixed small-scale bioreactors, which is summarized as scale-up effects. Identification of response mechanisms of the microorganism to various external perturbations is of great importance for pinpointing metabolic bottlenecks and targets for metabolic engineering. In this review, pulse response experimentation is proposed as an ideal way of obtaining kinetic information in combination with scale-down approaches for in-depth understanding of dynamic response mechanisms. As an emerging tool, computational fluid dynamics is able to draw a holistic picture of the fluid flow and concentration fields in the fermentor and finds its use in the optimization of fermentor design and process strategy. In the future, directed strain improvement and fermentor redesign are expected to largely depend on models, in which both microbial kinetics and fluid dynamics are thoroughly integrated.

To evaluate a change of chemical species of groundwater composition by the metabolism of microbes, which will be introduced to deep underground from the surface and be in a deep underground, is important for the discussion of the microbial effects on the performance assessment of the high-level radioactive waste repository. The purpose of this study is to develop of a microbial kinetics database to evaluate their activities in the deep underground environment.Some microbial metabolism data were collected and constructed their kinetics database for aerobic, denitrifying, manganese reducing, iron reducing, sulfate reducing, methanogenic and acetogenic bacteria to evaluate above groundwater chemistry. About 1260 data were selected by literature survey for some journals and books published from 1960s and summarized in this microbial kinetics database. Some sensitivity analyses were performed for some parameter of metabolism of microbes.

Process models play an important role in the bioreactor design, optimisation and control. In previous work, the bioreactor models have mainly been developed by considering the microbial kinetics and the reactor environmental conditions with the assumption that the ideal mixing occurs inside the reactor. This assumption is relatively difficult to meet in the practical applications. In this paper, we propose a new approach to the bioreactor modelling by expanding the so-called Herbert's microbial kinetics (HMK) model so that the developed models are able to incorporate the mixing effects via the inclusion of the aeration rate and stirrer speed into the microbial kinetics. The expanded models of Herbert's microbial kinetics allow us to optimize the bioreactor's performances with respects to the aeration rate and stirrer speed as the decision variables, where this optimisation is not possible using the original HMK model of microbial kinetics. Simulation and experimental studies on a batch ethanolic fermentation demonstrates the use of the expanded HMK models for the optimisation of bioreactor's performances. It is shown that the integration of the expanded HMK model with the computational fluid dynamics (CFD) model of mixing, which we call it as a kinetics multi-scale (KMS) model, is able to predict the experimental values of yield and productivity of the batch fermentation process accurately (with less than 5% errors).

A pesquisa por novas fontes de pigmentos naturais tem crescido, principalmente devido aos efeitos tóxicos causados por corantes sintéticos usados em alimentos, produtos farmacêuticos, têxteis e cosméticos. Nesse contexto, os pigmentos microbianos apresentam-se como alternativa para suprir essa demanda. Vários são os micro-organismos capazes de produzir pigmentos e, dentre eles, destaca-se o fungo filamentoso, Monascus. Este é capaz de produzir pigmentos amarelo, laranja e vermelho, e sua produção depende das condições em que é cultivado. Assim, os resíduos agroindustriais têm surgido como opção barata e rentável para a produção de biopigmentos. O presente estudo teve como objetivo avaliar o aproveitamento do soro de queijo como substrato para a produção de pigmentos por Monascus ruber CCT 3802. Para isso, primeiramente, buscou-se avaliar o crescimento radial do fungo em meio sólido sob concentrações de soro de queijo em pó e diferentes valores de pH. Os resultados demonstraram a potencialidade do soro de queijo como substrato para o crescimento do fungo, visto que houve diferença significativa entre as velocidades de crescimento obtidas para cada meio quando comparadas ao meio controle (sem soro de queijo). Quanto ao pH, as velocidades de crescimento do fungo foram maiores em pH 6,0. Em valores de pH extremos, como pH 2,0 e 8,0, o crescimento do fungo apresentou inibição e o aspecto visual diferiu-se, apresentando coloração amarela e vermelha, respectivamente. Isso demonstra a clara influência do pH na produção de pigmentos produzidos por M. ruber. Em estudos preliminares, buscou-se avaliar a produção de pigmentos alimentares por Monascus ruber em cultivo submerso, usando o soro de queijo como substrato. Meios de cultivo contendo glicose e soro de queijo em diferentes concentrações foram estudados e os resultados demonstraram maior produção de pigmentos foi obtida nos meios contendo apenas glicose. Por esse motivo, buscou-se utilizar a lactose, após o processo de hidrólise enzimática, como fonte de carbono para a produção de pigmentos por Monascus ruber. Meios de cultivo contendo glicose, lactose e lactose hidrolisada foram incubados a 30ºC em shaker, durante 7 dias. Apesar de conter menos de 43% de glicose, o meio contendo lactose hidrolisada apresentou produção máxima de pigmentos de 7,58 UA510, superando o cultivo contendo glicose. O pigmento produzido em lactose hidrolisada apresentou-se mais claro, porém mais vermelho e mais amarelo que em glicose. O consumo de açúcares redutores e produção de biomassa para o cultivo contendo apenas lactose foram inibidos, havendo declínio na produção de pigmentos após 72h de cultivo. Os resultados apresentados nesta pesquisa contribuem para que estudos futuros otimizem a hidrólise da lactose e, consequentemente, do soro de queijo, aproveitando-o como substrato para produção de biopigmentos por Monascus ruber. Research into new sources of natural pigments has grown, mainly due to the toxic effects caused by synthetic dyes used in food, pharmaceuticals, textiles and cosmetics. In this context, the microbial pigments are presented as an alternative to supply this demand. There are several microorganisms capable of producing pigments, among them the filamentous fungus, Monascus. This is capable of producing yellow, orange and red pigments, and its production depends on the conditions under which it is grown. Thus, agroindustrial wastes have emerged as a cheap and profitable option for the production of biopigments. The aim of the present study was to evaluate the use of cheese whey as a substrate for the production of pigments by Monascus ruber CCT 3802. For this purpose, we first sought to evaluate the radial growth of the fungus in solid medium under serum concentrations of cheese powder and different pH values. The results demonstrated the potential of whey as a substrate for fungus growth, since there was a significant difference between the growth rates obtained for each medium when compared to the control medium (without cheese whey). As for pH, growth rates of the fungus were higher at pH 6.0. At extreme pH values, such as pH 2.0 and 8.0, the growth of the fungus presented inhibition and the visual aspect differed, showing yellow and red coloration, respectively. This demonstrates the clear influence of pH on the production of pigments produced by M. ruber. Culture media containing glucose and cheese whey at different concentrations were studied and the results showed higher pigment production was obtained in the media containing only glucose. For this reason, the third part of the study sought to use lactose, after the enzymatic hydrolysis process, as a carbon source for the production of pigments by Monascus ruber. Culture media containing glucose, lactose and hydrolyzed lactose were incubated at 30°C in shaker for 7 days. Although it contained less than 43% of glucose, the medium containing hydrolyzed lactose presented maximum pigment production of 7.58 UA510, surpassing the culture containing glucose. The pigment produced in hydrolyzed lactose appeared lighter, but redder and more yellow than in glucose. The consumption of reducing sugars and biomass production for the culture containing lactose only were inhibited, with a decline in pigment production after 72 hours of cultivation. The results presented in this research contribute to the fact that future studies optimize the hydrolysis of lactose and, consequently, cheese whey, using it as a substrate for the production of biopigments by Monascus ruber. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

Study on Knowledge Attitude Practice about Rabies Pet Animals among School Children in Bangladesh

A mathematical model of microbial kinetics was introduced to predict the overall volumetric gas–liquid mass transfer coefficient (kLa) of carbon monoxide (CO) in a batch cultivation system. The cell concentration (X), acetate concentration (Cace), headspace gas (Nco and N co 2 ), dissolved CO concentration in the fermentation medium (Cco), and mass transfer rate (R) were simulated using a variety of kLa values. The simulated results showed excellent agreement with the experimental data for a kLa of 13/hr. The Cco values decreased with increase in cultivation times, whereas the maximum mass transfer rate was achieved at the mid-log phase due to vigorous microbial CO consumption rate higher than R. The model suggested in this study may be applied to a variety of microbial systems involving gaseous substrates.

Geological carbon sequestration captures CO2 from industrial sources and stores the CO2 in subsurface reservoirs, a viable strategy for mitigating global climate change. In assessing the environmental impact of the strategy, a key question is how microbial reactions respond to the elevated CO2 concentration. This study uses biogeochemical modeling to explore the influence of CO2 on the thermodynamics and kinetics of common microbial reactions in subsurface environments, including syntrophic oxidation, iron reduction, sulfate reduction, and methanogenesis. The results show that increasing CO2 levels decreases groundwater pH and modulates chemical speciation of weak acids in groundwater, which in turn affect microbial reactions in different ways and to different extents. Specifically, a thermodynamic analysis shows that increasing CO2 partial pressure lowers the energy available from syntrophic oxidation and acetoclastic methanogenesis, but raises the available energy of microbial iron reduction, hydrogenotrophic sulfate reduction and methanogenesis. Kinetic modeling suggests that high CO2 has the potential of inhibiting microbial sulfate reduction while promoting iron reduction. These results are consistent with the observations of previous laboratory and field studies, and highlight the complexity in microbiological responses to elevated CO2 abundance, and the potential power of biogeochemical modeling in evaluating and quantifying these responses.

Microbial fuel cells (MFCs) are novel bio-electrochemical device for spontaneous or single step conversion of biomass into electricity, based on the use of metabolic activity of bacteria. The design and use of MFCs has attracted considerable interests because of the potential new opportunities they offer for sustainable production of energy from biodegradable and reused waste materials. However, the associated slow microbial kinetics and costly construction materials has limited a much wider commercial use of the technology. In the past ten years, there has been significant new developments in MFCs which has resulted in several-fold increase in achievable power density. Yet, there is still considerable possibility for further improvement in performance and development of new cost effective materials. This paper comprehensively reviews recent advances in the construction and utilization of novel anodes for MFCs. In particular, it highlights some of the critical roles and functions of anodes in MFCs, strategies available for improving surface areas of anodes, dominant performance of stainless-steel based anode materials, and the emerging benefits of inclusion of nanomaterials. The review also demonstrates that some of the materials are very promising for large scale MFC applications and are likely to replace conventional anodes for the development of next generation MFC systems. The hurdles to the development of commercial MFC technology are also discussed. Furthermore, the future directions in the design and selection of materials for construction and utilization of MFC anodes are highlighted.

Our study designed to assess the stability of D-dimer levels and storage conditions, using two different techniques. This is the frst study to investigate the short-term storage stability of D-dimers in clinical citrated plasma samples containing a range of D-dimer concentrations. This study was performed with 60 samples that were collected randomly patients with suspected thromboembolism.Plasma samples were incubated for eight different time intervals (0 (i.e., fresh samples), 4, 24, 48, 72, 120, 168, and 240h) and at three different temperatures (25+2 °C,4+2 °C, and -20+2 °C) to evaluate the effect of storage conditions on D-dimer stability.Plasma D-dimer concentrations were determined using two different techniques, a fluorescence-based sandwich immunodetection assay (i-CHROMA, Boditech Med Inc., Korea) and an enzyme-linked immunosorbent assay (ELISA) (VIDAS, bioMerieux, France). In accordance with our study, we suggest D-dimer analysis be performed on plasma samples stored for

Geological carbon sequestration captures CO2 from industrial sources and stores the CO2 in subsurface reservoirs, a viable strategy for mitigating global climate change. In assessing the environmental impact of the strategy, a key question is how microbial reactions respond to the elevated CO2 concentration. This study uses biogeochemical modeling to explore the influence of CO2 on the thermodynamics and kinetics of common microbial reactions in subsurface environments, including syntrophic oxidation, iron reduction, sulfate reduction, and methanogenesis. The results show that increasing CO2 levels decreases groundwater pH and modulates chemical speciation of weak acids in groundwater, which in turn affect microbial reactions in different ways and to different extents. Specifically, a thermodynamic analysis shows that increasing CO2 partial pressure lowers the energy available from syntrophic oxidation and acetoclastic methanogenesis, but raises the available energy of microbial iron reduction, hydrogenotrophic sulfate reduction and methanogenesis. Kinetic modeling suggests that high CO2 has the potential of inhibiting microbial sulfate reduction while promoting iron reduction. These results are consistent with the observations of previous laboratory and field studies, and highlight the complexity in microbiological responses to elevated CO2 abundance, and the potential power of biogeochemical modeling in evaluating and quantifying these responses.

A previous implementation of optimal dynamic experiments for the identification of the Cardinal Temperature Model with Inflection, which describes the temperature effect on the microbial growth rate, revealed that the maximum growth temperature T max can only be estimated accurately when temperatures close to the true T max are included. Here, alternative approaches are considered. First, it is evaluated if the informative character of the optimal experiments can be improved by changing the temperature input structure. Simulations show that a simple profile, i.e., a constant phase followed by a linear temperature change and a second constant phase, is the most informative taking into account computational requirements and practical implementations. Second, experiments in which the temperature crosses the growth/inactivation interface are evaluated. The simulation study illustrates that the accuracy of T max largely depends on the selected temperature profile. A reliable T max is obtained when the initial temperature is slightly lower than the true T max . Starting above T max result in larger uncertainties. Generally, information at temperatures close to T max is required for an accurate T max estimate.

This research investigated the efficacy of gaseous ozone for the inactivation of Escherichia coli ATCC 25922 and NCTC 12900 strains in orange juice. Orange juice inoculated with E. coli (106 CFU mL-1) as a challenge microorganism was treated with ozone at 75-78µg mL-1 for different time periods (0-18 min). The efficacy of ozone for inactivation of both strains of E. coli was evaluated as a function of different juice types: model orange juice, fresh unfiltered juice, juice without pulp, and juice filtered through 500mm or 1mm sieves. Fast inactivation rates for total reduction of E. coli were achieved in model orange juice (60 seconds) and in juice with low pulp content (6 min). However, in unfiltered juice inactivation was achieved after 15-18 min. This indicated that juice organic matter interferes with antibacterial activity of gaseous ozone. The effect of prior acid (pH 5.0) exposure of E. coli strains on the inactivation efficacy of ozone treatment was also investigated. There was a strain effect observed, where prior acid exposure resulted in higher inactivation times in some cases by comparison with the control cells. However, the overarching influence on inactivation efficacy of ozone was related to the pulp content. Generally, the applied gaseous ozone treatment of orange juice resulted in a population reduction of 5 log cycles.

A previous implementation of dynamic experiments for the estimation of the parameters of the Cardinal Temperature Model with Inflection (CTMI), which describes the temperature effect on the microbial growth rate, revealed that the maximum growth temperature ( T max ) can only be estimated accurately when temperatures close to the true T max are included. As such, a reliable T max estimate is required at the beginning of the OED/PE implementation. Here, alternative experiments in which the temperature exceeds the growth/inactivation interface are evaluated. Results from the simulation study show that the accuracy and reliability of the T max estimate depends on the selected temperature profile. A very accurate and realistic T max value is obtained from experiments with an initial temperature slightly lower than the true T max . When the dynamic temperature starts at temperatures above T max , a larger uncertainty and variability is observed. From this, it can be concluded that information with respect to growth at temperatures close to T max is required for an accurate and reliable T max estimate. In a second step, two dynamic temperature profiles are implemented in a computer controlled bioreactor. The experimental data do not result in an accurate and reliable estimation of T max . Additional dynamic experiments are required to evaluate the proposed experimental set-up.

Using the logistic model as a starting point, a set of reparameterised equations were established which permit the easy calculation of the relevant parameters of microbial kinetics, together with their confidence limits, with the aim of establishing rigorous comparison between cultures under differing conditions. When the resource was used to evaluate the aptitude of peptones from diverse sources for the culture of lactic acid bacteria (LAB), a great variability was found, even among the results of commercial formulations with the same denomination. None of the peptones was able to maximise the growth – very active in fish peptones – and the production of the characteristic metabolites at the same time. Under these conditions, the application of the cluster analysis to kinetic parameters of proven descriptive capability becomes a useful exploratory method, which allows to decide combinations of protein sources apt to make compatible different potential purposes of LAB cultures. This way, it is possible to design factorial experiments to search optimum values for these purposes on the basis of hypothesis which avoid the selection of superfluous variables and inadequate domains.

The drivers for the establishment and composition of the sourdough microbiota, with particular emphasis on lactic acid bacteria, are reviewed and discussed. More than 60 different species of lactobacilli were identified from sourdoughs, showing the main overlapping between sourdough and human intestine ecosystems. The microbial kinetics during sourdough preparation was described by several studies using various methodological approaches, including culture-dependent and -independent (e.g., high throughput sequencing), and metabolite and meta-transcriptome analyses. Although the abundant microbial diversity harbored by flours, a succession of dominating and sub-dominating populations of lactic acid bacteria suddenly occurred during sourdough propagation, leading to the progressive assembly of the bacterial community. The contribution of all the potential sources (house microbiota, flour, types of flours and additional ingredients) for contaminating lactic acid bacteria was compared with the aim to find overlapping or specific routes that affect the sourdough microbiota. Once established and mature, pros and cons regarding the stability of the sourdough lactic acid bacteria biota were also reviewed, showing contradictory results, which were mainly dependent on the species/strains. Probably, the future research efforts should be dedicated to decrease the sources/drivers of noticeable variation rather than to full standardization of the process for sourdough preparation and use.

Traditional Italian pork products can be consumed after variable drying periods, where the temporal decrease of water activity spans from optimal to inactivating values. This makes it necessary to A) consider the bias factor when applying culture-medium-based predictive models to sausage; B) apply the dynamic version (described by differential equations) of those models; C) combine growth and death models in a continuous way, including the highly uncertain growth/no growth range separating the two regions. This paper tests the applicability of published predictive models on the responses of Listeria monocytogenes and Yersinia enterocolitica to dynamic conditions in traditional Italian pork sausage, where the environment changes from growth-supporting to inhibitory conditions, so the growth and death models need to be combined. The effect of indigenous lactic acid bacteria was also taken into account in the predictions. Challenge tests were carried out using such sausages, inoculated separately with L. monocytogenes and Y. enterocolitica , stored for 480 h at 8, 12, 18 and 20 °C. The pH was fairly constant, while the water activity changed dynamically. The effects of the environment on the specific growth and death rate of the studied organisms were predicted using previously published predictive models and parameters. Microbial kinetics in many products with a long shelf-life and dynamic internal environment, could result in both growth and inactivation, making it difficult to estimate the bacterial concentration at the time of consumption by means of commonly available predictive software tools. Our prediction of the effect of the storage environment, where the water activity gradually decreases during a drying period, is designed to overcome these difficulties. The methodology can be used generally to predict and visualise bacterial kinetics under temporal variation of environments, which is vital when assessing the safety of many similar products.

Aims: In previous studies the microbial kinetics of Escherichia coli K12 have been evaluated under static and dynamic conditions (Valdramidis et al. 2005, 2006). An acquired microbial thermotolerance following heating rates lower than 0·82°C min−1 for the studied micro-organism was observed. Quantification of this induced physiological phenomenon and incorporation, as a model building block, in a general microbial inactivation model is the main outcome of this work. Methods and Results: The microbial inactivation rate observed (kobs) under time-varying temperature conditions is studied and expressed as a function of the heating rate (dT/ dt). Hereto, a model building block related to the microbial physiology (kphys) under stress conditions is developed. Evaluation of the performance of the developed mathematical approach depicts that physiological adaptation is an essential issue to be considered when modelling microbial inactivation. Conclusions: Consideration, at a mathematical level, of microbial responses resulting in physiological adaptations contribute to the reliable quantification of the safety risks during food processing. Significance and Impact of the Study: By taking into account the physiological adaptation, the microbiological evolution during heat processing can be accurately assessed, and overly conservative or fail dangerous food processing designs can be avoided.

Bei der Berechnung mikrobieller Abbauprozesse in Grundwasserleitern, deren Abschatzung insbesondere zur Bewertung naturlicher Schadstoffminderung relevant ist, werden heutzutage viele unterschiedliche Modellansatze hinsichtlich der Abbaukinetik verwendet. In naturlichen Aquiferen ist durch Messungen kaum zu ermitteln, welche Kinetik dem mikrobiellen Abbau zugrunde liegt. Daher wird anhand eines einfachen im Computer generierten „virtuellen Aquifers“ demonstriert, welche Konsequenzen die Wahl eines Ansatzes zur Berechnung der mikrobiellen Kinetik auf die Simulationsergebnisse hat. Durch geeignete Wahl der erforderlichen Abbauparameter konnen alle untersuchten Ansatze ahnliche Schadstoffverteilungen fur eine noch instationare Abstromfahne berechnen. In der Prognose resultieren daraus jedoch unterschiedliche stationare Schadstoffverteilungen, und auch eine geringere Stromungsgeschwindigkeit fuhrt zu unterschiedlichen Prognosen der Abstromfahne. Ansatze zur Berechnung der mikrobiellen Kinetik, die einen Abbau unabhangig von Konzentrationen des Oxidationsmittels berechnen (z. B. Abbau erster Ordnung) erweisen sich als nicht prognosefahig.

Mycotoxin Testing with Aran Gas Aflatoxin B Mycotoxin Destruction using Allotropic Oxygen O O and O

Pokkah boengof sugarcane caused by Fusariumverticillioidesis is a destructive fungal disease in sugarcane growing regions In China the notable losses from pokkah boeng have occurred annually The main objectives of this study were to a nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp Field disease survey of natural disease incidenceof Pokkah boengin cultivars and cross combinations of sugarcane insugarcaneseedling nurserieslocated in Fuzhou China thedisease incidence ranged from b nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp Morphology characterization of F verticillioides was observed and identified by macroconidia microconidia conidiophoresand culture pigment characteristics c nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp nbsp Representing F verticillioidescausing pokkah boeng in sugarcane wasphylogenetic analyzed using translation elongation factor TEF ATP ATPase gene and internal transcribed spacer ITS gene regions Most of the isolates of the present study showed a similar grouping pattern in case of the three gene sequences however ITS and TEF more conservative than ATP ATPase gene in isolates of F verticillioides