Christopher Cannizzaro

Chattez avec Graph Search

Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.

AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.

Optimal control of fed-batch fermenters S. Valentinotti† C. Cannizzaro‡ M.Rhiel‡ U. Holmberg† U. von Stockar‡ D. Bonvin† †Institut d’Automatique, EPFL, 1015 Lausanne, Switzerland ‡Institut de Genie Chimique, EPFL, 1015 Lausanne, Switzerland Fermentors are often run in a fed-batch manner to avoid the formation of overﬂow metabolites. At a high growth rate, the most eﬃcient metabolic pathway(s) of certain microorganisms become saturated resulting in overﬂow metabolite production. These byproducts are undesira

Comprehensive in-situ bioreactor monitoring and control based on a midinfrared spectroscopic sensor system M. Rhiel1, C. Cannizzaro1, S. Valentinotti2, I. Marison1, U. von Stockar1 1 Institute of Chemical Engineering, 2Institute of Automatic Control Swiss Federal Institute of Technology (EPFL), CH- 1015 Lausanne, Switzerland Abstract A mid-infrared spectroscopic sensor system consisting of a spectrometer, a single attenuated total reflectance (ATR) probe immersed in the bioreactor, and a software package fo

A review, with refs. This contribution analyzes the position of biochem. engineering in general and bioprocess engineering particularly in the force fields between fundamental science and applications, and between academia and industry. By using culture technol. as an example, it can be shown that bioprocess engineering has moved slowly but steadily from an empirical art concerned with mainly know-how to a science elucidating the know-why of culture behavior. Highly powerful monitoring tools enable biochem.

Carotenoid prodn. by microorganisms, as opposed to chem. synthesis, could fulfill an ever-increasing demand for 'all natural' products. The yeast Phaffia rhodozyma has received considerable attention because it produces the red pigment astaxanthin, commonly used as an animal feed supplement. In order to have a better understanding of its metab., labeling expts. with [1-13C]glucose were conducted with the wildtype strain (CBS5905 T) and a hyper-producing carotenoid strain (J4-3) in order to det. their metabo

In this work, dielec. spectroscopy was used to monitor two CHO perfusion culture expts. (B14 and B16). The capacitance of the cell suspension was recorded every 20 min over an excitation frequency range of 0.2 MHz to 10.0 MHz. A phase plot of the capacitance at a low excitation frequency vs. the value at a higher frequency proved to be an accurate indicator of the major transition points of the culture, i.e., max. cell viability, end of lactate consumption, point of zero viability. For both expts., the capa

An in-situ, mid-IR sensor was used to monitor the major analyte concns. involved in the cultivation of Gluconacetobacter xylinus and the prodn. of gluconacetan, a food-grade exopolysaccharide. To predict the analyte concns., three different sets of std. spectra were used to develop calibration models, applying partial least-squares regression. It was possible to build a valid calibration model to predict the 700 spectra collected during the complete time course of the cultivation, using only 12 spectra coll

At high growth rates, the biomass yield of baker's yeast (Saccharomyces cerevisiae) decreases due to the prodn. of ethanol. For this reason, it is std. industrial practice to use a fed-batch process whereby the specific growth rate, m, is fixed at a level below the point of ethanol prodn., i.e., mcrit. Optimally, growth should be maintained at mcrit, but in practice, this is difficult because mcrit is dependent upon strain and culture conditions. In this work, growth was maintained at a point just above mcr

Since the yeast Phaffia rhodozyma was first described some 35 yr ago, there has been significant interest in the development of com. processes to exploit its ability to produce carotenoids (.apprx.80% astaxanthin). However, the optimal conditions for carotenoid prodn. are not well understood. A key limitation has been the lack of an appropriate sensor for online carotenoid quantification. In this study, an in situ Raman spectroscopy probe was used to monitor intracellular carotenoid prodn. for three consecu

Comprehensive and cGMP suitable bioprocess monitoring is still a challenge in microbial fermn. and cell culture process development. This paper discusses the exploitation of in-situ mid-IR spectroscopy in combination with partial least-squares anal. to monitor carbohydrate, amino acid, org. acid, pH, temp., and biomass content of Saccharomyces Cerevisiae, Phaffia rhodozyma, and CHO cell cultures. Reliability of the monitored values will be discussed for potential application in cGMP environments along with

Spectroscopic monitoring techniques have many advantages for bioprocess monitoring and control, including simultaneous multi-analyte detns., in-situ sterilizability, and low maintenance during operation. This study discusses the combined application of fluorescence, mid-IR, and Raman spectroscopic techniques for a comprehensive monitoring of Phaffia rhodozyma yeast cultures during batch and fed-batch operation for the prodn. of astaxanthin, a carotenoid of industrial importance. Reliability of the different

Christopher Cannizzaro

Chattez avec Graph Search

Optimal Control of Fed-Batch Fermenters

Comprehensive in-situ Bioreactor Monitoring and Control Based on a Mid-Infrared Spectroscopic Sensor System

Know-how and know-why in biochemical engineering

Metabolic network analysis on Phaffia rhodozyma yeast using 13C-labeled glucose and gas chromatography-mass spectrometry

On-line biomass monitoring of CHO perfusion culture with scanning dielectric spectroscopy

Methodology for real-time, multianalyte monitoring of fermentations using an in-situ mid-infrared sensor

Control of yeast fed-batch process through regulation of extracellular ethanol concentration

On-line monitoring of Phaffia rhodozyma fed-batch process with in situ dispersive raman spectroscopy

All-in-one bioprocess monitoring with a mid-IR spectroscopic sensor

Bioprocess monitoring and control using the combination of fluorescence, mid-IR, and Raman spectroscopy

Modeling for Control of Fed-Batch Fermenters

Spectroscopic monitoring of bioprocesses : a study of carotenoid production by "Phaffia Rhodozyma" yeast

An Optimal Operating Strategy for Fed-Batch Fermentations by Feeding the Overflow Metabolite

In-situ Monitoring and Control of Yeast Fermentations with MID-infrared Spectroscopy

Optimal Operation of Fed-Batch Fermentations via Adaptive Control of Overflow Metabolite

Fed-Batch Control of S. Cerevisiae and E. Coli at Critical Point Using Mid-FTIR Spectroscopy

In-Situ Bioreactor Monitoring and Control Based on Mid-Infrared Spectroscopic Measurements