325
Orange peel could be an attractive and promising substrate used in pectinase
production by submerged fermentation using Aspergillus niger. Results indicate
that at pH 2.2, a pectin yield of 15.5% was obtained from orange peels at 70 °C, and
of the three pectinolytic fungi isolated from natural environment and induced with
pectin from orange peels as a sole carbon source for pectinase production;
Aspergillus niger produced more pectinase than others. Upon partial purification, a
twofold increase in pectinase activity whose pH and temperature optima were 5.0
and 40 °C was obtained (Ezike et al. 2014). Furthermore, Patil and Dayanand (2006)
reported pectinase production using deseeded sunflower head under Submerged
Fermentation by Aspergillus niger DMF 27 and Aspergillus niger DMF 45 in
SSF. In both fermentations processes the pH of 5.0 and temperature of 34 °C were
ideal. Under optimum conditions, maximum production of exo-pectinase was
34.2 U g
−1
SSF (65% initial moisture) and endo-pectinase was 12.6 U mL
−1
in
Submerged Fermentation.
Pectinases production by Thermoascus aurantiacus in SSF was reported by
Martins et al. (2002) using wheat bran. The authors reached 43 U g
−1
of polygalacturonase at the 4th day of fermentation while pectin lyase (11,600 U g
−1
) was produced in the 14th day. The same authors reported the production using orange
bagasse (composed in dry material 11.8% fibre, 6.4% protein, 63% nitrogen, 6.7%
ash, 19% total sugar (9% reducing sugar) and 0.1% pectin), reaching 43 U g
−1
of
polygalacturonase after 6 days and 19,320 U g
−1
of pectin lyase. Solid State
Fermentation was conducted with initial moisture of 67%.
Mannanases
Mannanses are enzymes produced mainly from microorganisms but mannanases
produced from plants and animals have also been reported. Bacterial mannanases
are mostly extracellular and can act in a wide range of pH and temperature, though
acidic and neutral mannanases are more common (Dhawan and Kaur 2007).
Galactomannan-rich substrate locust bean gum (LBG) has been used widely as an
inducer of β-mannanase (Kote et al. 2009; Kim et al. 2011). Other substrates like
konjac powder, copra meal and wheat bran have also been practiced for the same
purpose, since they offer significant benefit due to their cheaper cost and abundant
availability (Zhang et al. 2009; Meenakshi et al. 2010; Chauhan et al. 2012).
Various microbes require different incubation times for maximum β-mannanase
production. In case of bacteria, it ranges from 24 h in Acinetobacter sp. ST 1-1
(Titapoka et al. 2008) to 96 h in Bacillus sp. MG-33 (Meenakshi et al. 2010). In
contrast to bacteria, fungi require 3 days in case of Streptomyces sp. PG-08-03
(Bhoria et al. 2009) to 11 days in Aspergillus ATCC 20114 (Mohamad et al. 2011).
The optimum temperature for mannanase production has been reported in the mesophilic range in most of the cases, and it corresponds with the growth temperature of
the respective microorganism. In general, bacteria prefer neutral to alkaline pH and
Exogenous Enzymes
Orange peel could be an attractive and promising substrate used in pectinase
production by submerged fermentation using Aspergillus niger. Results indicate
that at pH 2.2, a pectin yield of 15.5% was obtained from orange peels at 70 °C, and
of the three pectinolytic fungi isolated from natural environment and induced with
pectin from orange peels as a sole carbon source for pectinase production;
Aspergillus niger produced more pectinase than others. Upon partial purification, a
twofold increase in pectinase activity whose pH and temperature optima were 5.0
and 40 °C was obtained (Ezike et al. 2014). Furthermore, Patil and Dayanand (2006)
reported pectinase production using deseeded sunflower head under Submerged
Fermentation by Aspergillus niger DMF 27 and Aspergillus niger DMF 45 in
SSF. In both fermentations processes the pH of 5.0 and temperature of 34 °C were
ideal. Under optimum conditions, maximum production of exo-pectinase was
34.2 U g
−1
SSF (65% initial moisture) and endo-pectinase was 12.6 U mL
−1
in
Submerged Fermentation.
Pectinases production by Thermoascus aurantiacus in SSF was reported by
Martins et al. (2002) using wheat bran. The authors reached 43 U g
−1
of polygalacturonase at the 4th day of fermentation while pectin lyase (11,600 U g
−1
) was produced in the 14th day. The same authors reported the production using orange
bagasse (composed in dry material 11.8% fibre, 6.4% protein, 63% nitrogen, 6.7%
ash, 19% total sugar (9% reducing sugar) and 0.1% pectin), reaching 43 U g
−1
of
polygalacturonase after 6 days and 19,320 U g
−1
of pectin lyase. Solid State
Fermentation was conducted with initial moisture of 67%.
Mannanases
Mannanses are enzymes produced mainly from microorganisms but mannanases
produced from plants and animals have also been reported. Bacterial mannanases
are mostly extracellular and can act in a wide range of pH and temperature, though
acidic and neutral mannanases are more common (Dhawan and Kaur 2007).
Galactomannan-rich substrate locust bean gum (LBG) has been used widely as an
inducer of β-mannanase (Kote et al. 2009; Kim et al. 2011). Other substrates like
konjac powder, copra meal and wheat bran have also been practiced for the same
purpose, since they offer significant benefit due to their cheaper cost and abundant
availability (Zhang et al. 2009; Meenakshi et al. 2010; Chauhan et al. 2012).
Various microbes require different incubation times for maximum β-mannanase
production. In case of bacteria, it ranges from 24 h in Acinetobacter sp. ST 1-1
(Titapoka et al. 2008) to 96 h in Bacillus sp. MG-33 (Meenakshi et al. 2010). In
contrast to bacteria, fungi require 3 days in case of Streptomyces sp. PG-08-03
(Bhoria et al. 2009) to 11 days in Aspergillus ATCC 20114 (Mohamad et al. 2011).
The optimum temperature for mannanase production has been reported in the mesophilic range in most of the cases, and it corresponds with the growth temperature of
the respective microorganism. In general, bacteria prefer neutral to alkaline pH and
Exogenous Enzymes