cultures when incubated at 28
C kept under 175 rpm agitation rate (Vega et al.
2012). The cellulolytic fungal culture designated as PSSI-3 isolated from the paper
industry soil sample was noticed to show maximum CMCase activity when the
cultivation was carried out at 120 rpm for 3 days (Lekh Ram et al. 2014). As regards
agitation speed, 150 rpm resulted in maximum CMCase (2.40 IU/ml) and FPase
(0.278 IU/ml) production. Agitation rates fewer than 150 rpm resulted in declined
cellulase yields. The obstructing factor may be the insufficient dissolved oxygen
level for cell growth. Higher agitation rates resulted in a negligible decline in enzyme
levels, which could be due to mycelia destruction (Sarkar and Aikat 2014).
11.14 Effect of Carbon Source
The detrimental factor in any fermentation process is the carbon supplements which
show its impact critically on growth and production of the desired product. Carbon
sources may have either hindrance or stimulation on enzyme production. In another
study on T. reesei C5, peak cellulase enzyme production and growth was accomplished exercising lactose as solitary carbon additive (Muthuvelayudham et al.
2004). Hartree et al. (1988) and Hanif et al. (2004) proved that growth of
Trichoderma harzianum and A. niger on cellulosic residues resulted in increased
cellulase production. Triggering of cellulase production by trehalose was
demonstrated in Clostridium. (Thirumade et al. 2001). Cellulose induced cellulase
synthesis by tenfold while glucose acted as inhibitor (Jahangeer et al. 2005). In the
course of the growth Trichothecium roseum, an investigated fungus showed maximum total cellulolytic activity (1.87 FPU/ml) and extracellular protein content
(234 μg/ml) on potato dextrose yeast extract broth medium amended with 1%
(w/v) CMC (Shanmugam et al. 2008). Szakacs et al. (2006) and Baig (2005) opened
up that fructose and glucose repress the performance of enzyme activity, whereas
CMC, Avicel and lactose provoked Trichoderma spp. to release cellulase. Rashid
et al. (2009) revealed T. reesei when grown on effluent from palm oil mill produced
optimum cellulase at 0.5–1.5% cellulose as substrate.
The results which were drawn by Gautam et al. (2010) show that exoglucanases
of 2.68 U/ml, endoglucanase of 2.17 U/ml and β-glycosidases of 2.06 U/ml were
derived from filtrates comprising 1.0% sucrose succeeded by glucose, cellulose,
maltose and CMC. The inclusion of glucose in medium affected pronounced
repression of cellulose synthesis by Streptomyces albaduncus and Aspergillus
niger (Jyostna et al. 2015; Narasimha et al. 2006). Xylose at 3% amended with
1% cellulose as substrate exhibited raised FPase and CMCase while it was
repressed when cellulose was used as the one and only carbon supplement
(Srilakshmi et al. 2017).
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S. Akula and N. Golla
C kept under 175 rpm agitation rate (Vega et al.
2012). The cellulolytic fungal culture designated as PSSI-3 isolated from the paper
industry soil sample was noticed to show maximum CMCase activity when the
cultivation was carried out at 120 rpm for 3 days (Lekh Ram et al. 2014). As regards
agitation speed, 150 rpm resulted in maximum CMCase (2.40 IU/ml) and FPase
(0.278 IU/ml) production. Agitation rates fewer than 150 rpm resulted in declined
cellulase yields. The obstructing factor may be the insufficient dissolved oxygen
level for cell growth. Higher agitation rates resulted in a negligible decline in enzyme
levels, which could be due to mycelia destruction (Sarkar and Aikat 2014).
11.14 Effect of Carbon Source
The detrimental factor in any fermentation process is the carbon supplements which
show its impact critically on growth and production of the desired product. Carbon
sources may have either hindrance or stimulation on enzyme production. In another
study on T. reesei C5, peak cellulase enzyme production and growth was accomplished exercising lactose as solitary carbon additive (Muthuvelayudham et al.
2004). Hartree et al. (1988) and Hanif et al. (2004) proved that growth of
Trichoderma harzianum and A. niger on cellulosic residues resulted in increased
cellulase production. Triggering of cellulase production by trehalose was
demonstrated in Clostridium. (Thirumade et al. 2001). Cellulose induced cellulase
synthesis by tenfold while glucose acted as inhibitor (Jahangeer et al. 2005). In the
course of the growth Trichothecium roseum, an investigated fungus showed maximum total cellulolytic activity (1.87 FPU/ml) and extracellular protein content
(234 μg/ml) on potato dextrose yeast extract broth medium amended with 1%
(w/v) CMC (Shanmugam et al. 2008). Szakacs et al. (2006) and Baig (2005) opened
up that fructose and glucose repress the performance of enzyme activity, whereas
CMC, Avicel and lactose provoked Trichoderma spp. to release cellulase. Rashid
et al. (2009) revealed T. reesei when grown on effluent from palm oil mill produced
optimum cellulase at 0.5–1.5% cellulose as substrate.
The results which were drawn by Gautam et al. (2010) show that exoglucanases
of 2.68 U/ml, endoglucanase of 2.17 U/ml and β-glycosidases of 2.06 U/ml were
derived from filtrates comprising 1.0% sucrose succeeded by glucose, cellulose,
maltose and CMC. The inclusion of glucose in medium affected pronounced
repression of cellulose synthesis by Streptomyces albaduncus and Aspergillus
niger (Jyostna et al. 2015; Narasimha et al. 2006). Xylose at 3% amended with
1% cellulose as substrate exhibited raised FPase and CMCase while it was
repressed when cellulose was used as the one and only carbon supplement
(Srilakshmi et al. 2017).
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S. Akula and N. Golla