Conidiation ofTrichoderma atroviride isolate during submerged cultivation in a laboratory stirred-tank fermenter

Abstract

Conditions for conidiation of a natural isolate of Trichoderma atroviride during submerged cultivation in Erlenmeyer flasks and in a laboratory stirred-tank fermenter were optimized. From the simple sugars tested, cellobiose was the best substrate for conidia production while cellulose fines from paper mill waste proved to be a suitable cheap complex carbon source. Optimum temperature for conidiation was 24-26 degrees C, and the required dissolved oxygen level was > 40% saturation. After initial slight decrease during the 1st d after inoculation, the pH of the culture medium constantly increased throughout the sporulation period. Attempts to regulate the pH during fermentation did not improve the spore yields. The most intense formation of conidia took place between 2nd and 3rd d of growth and the overall volumetric productivity of conidia was 4.1-8.2 x 10(9) conidia per L/h.

Effects of temperature, light and incubation period on production, germination and bioactivity ofTrichoderma atroviride

“…This study examined the effects of several abiotic factors on conidium production, germination and bioactivity of T. atroviride LU132. Optimum conidium production at 25°C was similar to that reported by Jakubikova et al (2006) for large-scale conidium production of T. atroviride during submerged cultivation. Furthermore, Longa et al (2008) studying ecophysiological requirements of T. atroviride strain SC1, demonstrated that the strain grew best at 25°C.…”

“…The low (20°C) and high (30°C) temperatures examined in this study resulted in less conidium production than occurred at the optimum temperature (25°C). This is similar to conidium production for other biological control fungi, including Zoophthora radicans (Milner and Lutton 1983), Trichoderma harzianum (Knudsen et al 1991), Metarhizium flavoviride (Thomas and Jenkins 1997) and T. atroviride (Jakubikova et al 2006). Study of the bioherbicide pathogen, Rhynchosporium alismatis, has similarly shown that while conidium production and germination were decreased at low temperature, high temperature (35°C) inhibited growth and conidium production but not germination (Jahromi et al 1998).…”

“…Optimum conidium production at 25°C was similar to that reported by Jakubikova et al . () for large‐scale conidium production of T. atroviride during submerged cultivation. Furthermore, Longa et al .…”

Effect of Moisture on Trichoderma Conidia Production on Corn and Wheat Bran by Solid State Fermentation

“…have been published. However, few studies were found regarding spore production, all of them considering submerged fermentation (Verma et al 2005(Verma et al , 2006(Verma et al , 2007Jakubikova et al 2006;Jin et al 1996). The results for conidia production in submerged fermentation were expressed as colony-forming unit per milliliter (CFU/ml) after incubation on agar; thus, the results cannot be directly compared.…”

Metabolic engineering and thermodynamic characterization of an extracellular -glucosidase produced by Aspergillus niger

“…β-Glucosidase can be produced both by solid-state and submerged fermentation techniques (Christakopoulos et al, 1995;Iembo et al, 2002;Fawzi, 2003;Garcia-Kirchner et al, 2005;Daroit et al, 2007;Leite et al, 2007). Sub-merged fermentation offers several advantages, among them a possibility to automate many operations, the ease with which various parameters can be monitored (by periodic sampling of broth) and controlled if necessary by the addition of further nutrients or reagents and easier removal of heat generated during the microbial growth in a large scale reactor (Jakubikova et al, 2006). Extracellular production of β-glucosidase using submerged fermentation technique had been investigated by different researchers.…”