Advanced near‐infrared monitor for stable real‐time measurement and control of Pichia pastoris bioprocesses

Abstract

Near‐infrared spectroscopy is considered to be one of the most promising spectroscopic techniques for upstream bioprocess monitoring and control. Traditionally the nature of near‐infrared spectroscopy has demanded multivariate calibration models to relate spectral variance to analyte concentrations. The resulting analytical measurements have proven unreliable for the measurement of metabolic substrates for bioprocess batches performed outside the calibration process. This paper presents results of an innovative near‐infrared spectroscopic monitor designed to follow the concentrations of glycerol and methanol, as well as biomass, in real time and continuously during the production of a monoclonal antibody by a Pichia pastoris high cell density process. A solid state instrumental design overcomes the ruggedness limitations of conventional interferometer‐based spectrometers. Accurate monitoring of glycerol, methanol, and biomass is demonstrated over 274 days postcalibration. In addition, the first example of feedback control to maintain constant methanol concentrations, as low as 1 g/L, is presented. Postcalibration measurements over a 9‐month period illustrate a level of reliability and robustness that promises its adoption for online bioprocess monitoring throughout product development, from early laboratory research and development to pilot and manufacturing scale operation. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:749–759, 2014

Near-infrared spectroscopy in upstream bioprocesses

“…Goldfeld et al [26] have recently evaluated the use of an NIR device for real-time monitoring and control of a Pichia pastoris bioprocess. Six fermentations took place in 1.6-and 3-l reactors.…”

Advances in process monitoring tools for cell culture bioprocesses

“…Using an instrumentation system that employs a proprietary signal processing algorithm, it was shown that NIR can be used to monitor glycerol, methanol, and biomass concentration in the fermentation of Pichia pastoris . The accuracy of the on‐line measurement allowed its use in the controlled methanol feeding to maintain its concentration at a low level . A challenge of using NIR for nutrient concentration measurement is the extensive experimentation and data analysis development effort needed to make the system work.…”

Real‐time monitoring of ethanol production during Pichia stipitis NRRL Y‐7124 alcoholic fermentation using transflection near infrared spectroscopy

“…Saccharomyces cerevisiae is the most widely used yeast in alcoholic fermentation because Correspondance: Dr. María Guadalupe Aguilar-Uscanga (gaguilar@itver.edu.mx), Bioengineering Laboratory, Food Research and Development Unit, Veracruz Institute of Technology, Av. Development and bioprocess optimization are highly dependent on accurate real-time monitoring of chemical and physical process variables [11][12][13]. Some investigators have published studies using xylose-fermenting recombinant S. cerevisiae strains to solve this problem [3][4][5][6].…”