Biomedical Engineering Reference
In-Depth Information
Table 5.2
Common strains for pectin enzyme production [
69
]
Microbes
Genus
Mycetes
Aspergillus
spp.
, Penicillium
spp.,
Rhizopus
spp.,
Fusarium
spp.,
Geotrichum
spp.
Bacteria
Erwinia
spp.,
Pseudomonas
spp.,
Bacillus
spp.,
Clostridium
spp.,
Xanthomonas
spp.
Yeast
Trichosporm
spp.,
Kluyveromyces
spp.,
Saccharomyces
spp.,
Aureobasidium
spp.
of pectinase by treatment of
Aspergillus niger
cp-831with 0.03 % nitrosoguanidine;
the strain cultivation was scaled up by the Wuxi Enzyme Factory. Chen and Zhao
[
71
,
72
] reported on studies about pectinase production by liquid and solid-state
fermentation of
Aspergillus oryzae
C491.
5.3.3.2
Pectinase Production by Microbial Fermentation
Pectinase is prepared by microbial fermentation mainly by three methods: liquid
fermentation, solid-state fermentation, and immobilized cell cultivation. Solid-state
fermentation is widely used for pectinase production in China because it requires
less investment, has a fast start, and has other advantages. Most of the pectin
substrates for liquid fermentation are from different sources of pectin products,
and for solid-state fermentation, lignocellulosic agricultural waste or agroprocess-
ing by-products are used as carbon sources and pectinase inducer [
73
]. Sharma
and Satyanarayana [
74
] used liquid fermentation of
Bacillus pumilus
to produce
pectinase that was stable in high alkaline and thermal conditions. Botella et al.
[
75
] used grape pomace as a substrate and
Aspergillus awamori
as the inoculum to
produce circumscribed polygalacturonase by solid-state fermentation. Studies from
Almeida et al. [
76
] showed that a bioreactor with a circular flow packed bed favored
immobilization of
Kluyveromyces marxianus
CCT 3172 cells to produce pectinase.
Different culture methods have different effects on the pectinase production.
Maldonado and Strasser de Saad [
77
] compared the characteristics of pectinase
synthesized by two culture methods of
A. niger
. They claimed that the regulation
of pectinase synthesis is different under different culture conditions. The yields of
pectinesterase and polygalacturonase in solid-state fermentation using pectin as the
sole carbon source were four and six times greater compared with that of submerged
fermentation, respectively. The extra glucose added under solid-state fermentation
conditions was conducive for improving the production of pectinesterase and
polygalacturonase, but the glucose added under submerged fermentation conditions
significantly affected the synthesis of pectinesterase and polygalacturonase. Viviana
[
78
] also pointed out that, for
A. niger
, there were distinct physiological responses to
different culture methods. The fermentation conditions have a great influence on the
composition of fungal pectinase and the kinetic and chemical characteristics of the
enzyme. The production of pectinesterase under submerged fermentation conditions
was five times greater compared with that under solid-state fermentation conditions;
the yield of pectinesterase increased 30 %. However, the production of pectinolytic
