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.

T Panda

Department Of Chemical Engineering

Kalaimahan Théodore

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

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

Enzyme and Microbial Technology

Azadirachtin, a well-known biopesticide, is a secondary metabolite extracted from the seeds of Azadirachta indica. In the present study, azadirachtin was produced in hairy roots of A. indica, generated by Agrobacterium rhizogenes-mediated transformation of leaf explants. Liquid cultures of A. indica hairy roots were developed with a liquid-to-flask volume ratio of 0.15. The kinetics of growth and azadirachtin production were established in a basal plant growth medium containing MS medium major and minor salts, Gamborg's medium vitamins, and 30 g l -1 sucrose. The highest azadirachtin accumulation in the hairy roots (up to 3.3 mg g -1) and azadirachtin production (~44 mg l -1) was obtained on Day 25 of the growth cycle, with a biomass production of 13.3 g l -1 dry weight. To enhance the production of azadirachtin, a Plackett-Burman experimental design protocol was used to identify key medium nutrients and concentrations to support high root biomass production and azadirachtin accumulation in hairy roots. The optimal nutrients and concentrations were as follows: 40 g l -1 sucrose, 0.19 g l -1 potassium dihydrogen phosphate, 3.1 g l -1 potassium nitrate, and 0.41 g l -1 magnesium sulfate. Concentrations were determined by a central composite design protocol and verified in shake-flask cultivation. The optimized medium composition yielded a root biomass production of 14.2 g l -1 and azadirachtin accumulation of 5.2 mg g -1, which was equivalent to an overall azadirachtin production of 73.84 mg l -1, 68% more than that obtained under non-optimized conditions. © 2011 The Society for In Vitro Biology.

In Vitro Cellular and Developmental Biology - Plant

Statistical medium optimization for enhanced azadirachtin production in hairy root culture of Azadirachta indica

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.

Bioresource Technology

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

The reaction conditions were optimized for enzymatic hydrolysis of pectic substances using pectolytic enzymes produced by Aspergillus niger NCIM 548. Response surface methodology was used to optimize the reaction parameters and the central composite design was employed for this purpose. Pectin was used as the substrate for polymethylgalacturonase and pectinlyase, whereas polygalacturonic acid was the substrate for polygalacturonase. The volume ratio of reactants for maximum hydrolysis was determined under the assay conditions. The optimum amount of substrate and enzyme were found to be 0.2 cm3 and 0.074 cm3 for polymethylgalacturonase, 0.4 cm3 and 0.086 cm3 for polygalacturonase, and 0.63 cm3 and 0.7 cm3 for pectinlyase. The pH and temperature optima were found to be 5.3 and 30°C for polymethylgalacturonase, 6.6 and 26°C for polygalacturonase, and 4.8 and 35°C for pectinlyase. Under optimized conditions the enzyme activities were higher when compared to unoptimized conditions. Copyright (C) 1999 Elsevier Science Inc.The reaction conditions were optimized for enzymatic hydrolysis of pectic substances using pectolytic enzymes produced by Aspergillus niger NCIM 548. Response surface methodology was used to optimize the reaction parameters and the central composite design was employed for this purpose. Pectin was used as the substrate for polymethylgalacturonase and pectinlyase, whereas polygalacturonic acid was the substrate for polygalacturonase. The volume ratio of reactants for maximum hydrolysis was determined under the assay conditions. The optimum amount of substrate and enzyme were found to be 0.2 cm3 and 0.074 cm3 for polymethylgalacturonase, 0.4 cm3 and 0.086 cm3 for polygalacturonase, and 0.63 cm3 and 0.7 cm3 for pectinlyase. The pH and temperature optima were found to be 5.3 and 30°C for polymethylgalacturonase, 6.6 and 26°C for polygalacturonase, and 4.8 and 35°C for pectinlyase. Under optimized conditions the enzyme activities were higher when compared to unoptimized conditions.

Performance of pectolytic enzymes during hydrolysis of pectic substances under assay conditions: A statistical approach

Surface and submerged culture studies were carried out for the production of extracellular β-1,3-glucanase and carboxymethylcellulase from Trichoderma harzianum, NCIM 1185. The different parameters which influence the enzyme production, viz., spore age in the slant growth, seed age, and pH (initial) of the production medium have been optimized. The ranges of these parameters studied were: Spore age of T. harzianum between 2 and 10 days, seed age between 12 h and 48 h, and pH (initial) between 3 and 7. The other conditions of fermentation were: Temperature 30°C, gyratory shaker speed 160 rev. min-1. It was observed that the activities of β-1,3-glucanase and carboxymethylcellulase varied during the entire fermentation cycle which had a distinct effect on protoplast generation from T. reesei mycelium. The optimum values of the above-mentioned parameters for lytic enzymes production were: Spore age of T. harzianum in the slant growth 5 days, seed age 36 h, and pH (initial) 5.0 for both surface and submerged culture processes. © 1994 Springer-Verlag.

Bioprocess Engineering

Production of β-1,3-glucanase from Trichoderma harzianum in surface and submerged culture processes and its role on protoplast generation from Trichoderma reesei mycelium

Efficient synthesis of a large number of viable protoplasts from Trichoderma longibrachiatum (Trichoderma reesei) mycelium has been found to be influenced by a number of factors. In this case, Trichoderma harzianum NCIM 1185 culture filtrate has been used to prepare protoplasts from Trichoderma longibrachiatum QM 9414. A method has been devised to isolate a large number of viable protoplasts from the mycelium. Detailed analysis of different factors affecting the synthesis of protoplasts from T. longibrachiatum has not yet been reported. The most suitable conditions for protoplasting were as follows: age of the organism in slant, 3 days; mycelium age, 20 h; volume of lytic enzymes, 190 ml; mycelial weight (dry equivalent), 1.66 g; time of contact with lytic enzymes, 2 h; temperature of protoplasting, 30°C; phosphate buffer, 25 mm, pH 6.5; KCl as osmotic stabilizer, 0.7 m. Proper spreading of the mycelium in contact with the lytic enzymes was also found to be necessary. © 1992.

Journal	Enzyme and Microbial Technology
ISSN	01410229
Open Access	No