The generalized distance function approach is employed to obtain a suitable near optimal conditions of variables. The optimal values of variables (medium constituents, microbiological parameters, and process parameters) have been evaluated separately using single responses (either specific esterase activity or cell mass) as per central-composite-design and multi-responses following generalized distance function approach. The optimal conditions (medium composition (g l-1): dextrose, 13.43; peptone, 7.285; yeast extract, 2.55; and malt extract, 1.695; microbiological parameters: slant age, 39.9 h; inoculum age, 9.6 h; and number of cells, 1.49 × 108 numbers ml-1; process conditions: temperature, 29.9 °C; and pH, 6.2) obtained by generalized distance approach can be considered as a 'near optimal' solution of interactive multi-response systems of intracellular esterase synthesis by Saccharomyces cerevisiae. © 2007 Elsevier Ltd. All rights reserved.

T Panda

Department Of Chemical Engineering

Microbiology

Optimization

Synthesis (chemical)

yeast

ESTERASE

GENEARLIZED DISTANCE FUNCTION APPROACH

Enzymes

glucose

PEPTONE

CEREAL

Critical analysis

enzyme

Inoculation

ketone

sugar

article

cell count

enzyme activity

enzyme synthesis

MALT

nonhuman

priority journal

Saccharomyces cerevisiae

separation technique

Temperature

Culture Media

ESTERASES

Kinetics

Saccharomyces cerevisiae Proteins

Substrate Specificity

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Bioresource Technology

A common problem generally encountered during manufacturing process improvement involves simultaneous optimization of multiple 'quality characteristics' or so-called 'responses' and determining the best process operating conditions. Such a problem is also referred to as 'multiple response optimization (MRO) problem'. The presence of interaction between the responses calls for trade-off solution. The term 'trade-off' is an explicit compromised solution considering the bias and variability of the responses around the specified targets. The global exact solution in such types of nonlinear optimization problems is usually unknown, and various trade-off solution approaches (based on process response surface (RS) models or without using process RS models) had been proposed by researchers over the years. Considering the prevalent and preferred solution approaches, the scope of this paper is limited to RS-based solution approaches and similar closely related solution framework for MRO problems. This paper contributes by providing a detailed step-by-step RS-based MRO solution framework. The applicability and steps of the solution framework are also illustrated using a real life in-house pin-on-disc design of experiment study. A critical review on solution approaches with details on inherent characteristic features, assumptions, limitations, application potential in manufacturing and selection norms (indicative of the application potential) of suggested techniques/methods to be adopted for implementation of framework is also provided. To instigate research in this field, scopes for future work are also highlighted at the end. © 2018 World Scientific Publishing Company.

International Journal of Reliability, Quality and Safety Engineering

A solution framework for response surface-based multiple quality characteristics optimization

Esterase plays a major role in the degradation of natural materials and industrial pollutants, viz., cereal wastes, plastics, and other toxic chemicals. It is useful in the synthesis of optically pure compounds, perfumes, and antioxidants. The potential applications of esterase with reference to agriculture, food, and pharmaceutical industries, are discussed in this review. Promising applications in this avenue can be supported by appropriate production strategies. © Springer-Verlag 2005.

Applied Microbiology and Biotechnology

Production and applications of esterases

Taguchi's method was applied to evaluate the significant parameters for griseofulvin production by Penicillium griseofulvum MTCC 1898 in a batch bioreactor. Physical parameter, viz., controlled pH, agitation and aeration had a significant influence on griseofulvin production when compared with chemical parameters and were considered as significant ones. © 2002 Published by Elsevier Science Ltd.

Process Biochemistry

Determination of significant parameters for improved griseofulvin production in a batch bioreactor by Taguchi's method

The chitinase fermentation process utilizing chitin as the sole carbon source was investigated in a stirred tank bioreactor. Agitator speed of 224 rpm was found to be most suitable for cell growth as well as for chitinase production. Chitinase yield decreased rapidly at higher agitator speed, while decrease in cell yield at higher agitator speed was not rapid. Probably, mass transfer limitation was predominant in the fermentation process at lower agitator speed. Higher agitator speed appears to reduce chitinase production.

Biochemical Engineering Journal

Submerged culture production of chitinase by Trichoderma harzianum in stirred tank bioreactors - The influence of agitator speed

Statistical design was used to determine the optimal levels of medium components, the optimal initial pH of the enzyme production medium, the temperature of fermentation, age of the organism in the slant growth and the age of the inoculum for the production of chitinase in shake flask fermentations. The use of high concentrations of chitin and ammonium sulphate and exclusion of peptone and urea from the medium resulted in the production of higher level of the enzyme. The optimal concentrations of the medium components were 12.5 kg/m3 and 4.2 kg/m3 for the chitin and ammonium sulphate respectively. The effect of the addition of peptone and urea to the optimized medium was studied. The optimal values of initial pH and temperature were 5.6 and 28 °C respectively. The optimal age of the slant and the inoculum were found to be 105 h and 43 h respectively. The highest level of chitinase before optimization of the above variables was 0.054 U which was maximized to the level of 0.197 U.

Bioprocess Engineering

Optimization of carbon and nitrogen sources in the medium and environmental factors for enhanced production of chitinase by trichoderma harzianum

Response surface methodology was employed to study the effect of temperature and initial pH on the production of β-1,3-glucanase and carboxymethylcellulase from Trichoderma harzianum in both surface culture and submerged culture experiments. The efficiency of the enzymes in generating protoplasts from Trichoderma reesei mycelium was also studied. Regression analysis was performed on the data obtained. A temperature of 30°C and an initial pH of 4.7 were found to be optimal for β-1,3-glucanase production from T. harzianum in both surface culture and submerged culture processes. © 1995.

Enzyme and Microbial Technology

Application of response surface methodology to evaluate the influence of temperature and initial pH on the production of β-1,3-glucanase and carboxymethylcellulase from Trichoderma harzianum

Critical analysis of application of generalized distance function for optimization of important variables for esterase synthesis by Saccharomyces cerevisiae

Journal	Bioresource Technology
ISSN	09608524
Open Access	No