Gluconic acid production

The first example employed an immobilization of GOx and a pH-sensitive dye (l-hydroxypyrene-3,6,8-trisulfonate, HPTS) on the tip of an optical fiber.44 As the local pH was reduced by gluconic acid production, measurable changes in fluorescence were observed. Using flow-through measurements with buffer solutions of various strengths, the optrode response time was determined to be 8-12 min, with a detection limit of 1.8-36 mg/dL glucose and response saturation at 36-54 mg/dL. 

Roukas, T. 2000. Citric and Gluconic Acid Production from Fig by Aspergillus niger Using Solid-State Fermentation. J. Ind. Microbiol. Biotechnol., 25, 298-304. 

Singh, O.V., Jain, R.K. and Singh, R.P. 2003. Gluconic Acid Production Under Varying Fermentation Conditions by Aspergillus Niger. J. Chem. Technol. Biotechnol., 78, 208-212. 

Operating conditions of gluconic acid production Maximization of overall production rate and the final concentration of the gluconic acid while minimizing the final substrate concentration at the end of fermentation process. Net Flow Method (NFM) Pareto-domain was first found by a procedure which includes an evolutionary algorithm. Halsall-Whitney etd. (2003)... 

Halsall-Whitney, H., Taylor, D. and Thibault, J. (2003). Multicriteria optimization of gluconic acid production using net flow. Bioprocess Biosyst. Eng., 25, pp. 299-307. 

Keywords Net flow method, rough set method, thresholds, concordance index, discordance index, preference and non-preference rules, ranking, gluconic acid production. 

NFM and RSM are used in this case study to optimize the gluconic acid production. The primary objectives of this process are to maximize simultaneously the overall production rate and the final concentration of gluconic acid. The simulation of the fermentation of glucose to gluconic acid by the micro-organism Pseudomonas ovalis in a batch stirred tank reactor is performed. The overall biochemical reaction can be expressed as ... 

Table 7.9 Values of parameters for the simulation of gluconic acid production.

Using the final substrate concentration is undoubtedly excessive in this case study because, by forcing the highest gluconic acid productivity and concentration as in the two-objective optimization problem, a small final substrate concentration was also obtained. It was added in this case study to explore the influence of this objective function on the performance of NFM to find a judicious compromise for a three-objective optimization problem. The location of the best 5% of the... 

Table 7.13 Summary of the MOO of gluconic acid production - best solutions.

Ghose, T.K. and P. Gosh (1976). Kinetic analysis of gluconic acid production by Pseudomonas ovaUs. J. App. Chem. Biotechnol., 26, 768-777. 

The absolute activity for gluconic acid production is obtained if the specific activity of the different preparations is multiplied with the cell concentration. The non-dotted curve in Figure 10 Is the result of this calculation, which gives a good... 

Figure 10. Catalytic effectiveness (activity in % ) and absolute catalytic activity as a function of cell concentration for gluconic acid production from glucose with calcium alginate immobilized Acetobacter simplex cells. Reprinted, with permission, from Ref. 13. Copyright 1982, Plenum Publishing Corp.

New Gluconic Acid Process The biomass based gluconic acid production... 

Figure 4 Comparative analysis of glucose and gluconic acid production from cellulose demonstrating inhibition of cellulolytic enzymes by cellulose hydrolysis products...

Anastassiadis S, Aivasidis A, Wandrey C Continuous gluconic acid production by isolated yeast-like mould strains of Aureobasidium pullulans. Appl Microbiol Biotechnol. 2003, 61, 110-7 and references there in. Valjamae P, Petterson G, and Johansson G, Eur. J. Biochem. 2001, 268, 4520-4526. 

Attwood, M. M., van Dijken, J. P., Pronk, J. T. (1991). Glucose metabolism and gluconic acid production by Acetobacter diazotrophicus. Journal of Fermentation and Bioengineering, 72(2), 101-105. 

Reuss et al. [1986] modeled this process on the basis of a careful experimental program. The kinetics of gluconic acid production were described by means of the Michaelis-Menten equation (Section 1.5.1 of Chapter 1). At a pH of 5.6 the constant Km in that equation amounted to 0.36 mmol/h and the specific oxygen uptake rate (half of the specific production rate, yp) 65 mol oxygen per kg dry weight and per hour. 

Scale-down design based on regime analysis was introduced by Oosterhuis in 1984 [11] in a study of the process for gluconic acid production. Oosterhuis proposed four steps for scaling down ... 

As the second example, the scale-down study performed by Oosterhuis [11] is summarized. Table 2.2 lists characteristic times based on estimations for a 25 m STR equipped with two standard Rushton impellers used for gluconic acid production. In this example, the time constant for oxygen transfer (Iqt) longer than that for oxygen consumption (loc)> therefore oxygen limitation is... 

Table 2.2 Some characteristic times for gluconic acid production in a 25 m stirred-tank reactor.

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