323
both strains the maximum cellulasic activity occurred between 72 h and 96 h of
incubation at 30 °C.
Waseem et al. (2014) reported that CB-2 and CB-3 strains of Bacillus subtilis
were used for the flask-scale production of cellulase through submerged fermentation. Results revealed the highest cellulolytic activity (CMCase) with 120.321 U/ml
and filter paper activity (FPase) with 1.076 U/ml by CB-2 strain followed by CB-3.
Optimum temperature and pH of the medium for cellulase production was 37.5 °C,
pH and 9 respectively, with 2% untreated cotton stalk as carbon source, yeast as
organic nitrogen source and ammonium sulphate as inorganic nitrogen source with
3% inoculum size.
Ariffin et al. (2006) conducted a study to produce cellulase by local isolate
Bacillus pumilus EB3, using carboxymethyl cellulose (CMC)as substrate. Following
that, cellulase produced from Bacillus pumilus EB3 was purified using ion exchange
chromatography with anion exchanger (HiTrap QXL) for characterization of the
cellulase. Cellulase was successfully produced in 2 L stirred tank reactor (STR)
with the productivity of 0.53, 3.08 and 1.78 U/L h and the maximum enzyme activity of 0.011, 0.079 and 0.038 U/mL for FPase, CMCase and β-glucosidase, respectively. Purification of cellulase from Bacillus pumilus EB3 using ion exchange
chromatography showed that 98.7% of total CMCase was recovered.
Xylanases
Xylanase production has been documented in a wide spectrum of microorganisms,
including bacteria, actinomycetes, yeasts and filamentous fungi (Nascimento et al.
2003; Bakri et al. 2008). Studying the effect of orange pomace, orange peel, lemon
pomace, lemon peel, apple pomace, pear peel, banana peel, melon peel and hazelnut
shell on the production of xylanase, using Trichoderma harzianum 1073-D3, Seyis
and Aksoz (2005) discovered that molasses are able to reduce the time of production
in 50% when used as an additional carbon source. The maximum activity has been
observed on 2.5% melon peel medium (26.5 U mg
−1
of protein)incubated at 30 °C
for 7 days on a rotary shaker (150 rpm).
Rose and Van Zyl (2008) optimized xylanase production using a recombinant
strain of Aspergillus niger D15[xyn2]pyrG
−
. The highest xylanase activities of 226
and 209 U mL
−1
were produced with 20 and 30% molasses, respectively, at 30 °C,
pH 6.5, agitation of 100 rpm and a spore inoculum of 1.106 spores mL
−1
. In another
study Maciel et al. (2009) also produced xylanase with sugarcane bagasse under
SSF by Aspergillus niger LPB 326. The highest xylanase activity was 2327 U gdm
−1
using 65% of sugarcane bagasse and 35% of soybean meal supplemented with a
mineral salt solution, 85% initial moisture, 106 spores gdm
−1
,at 30 °C for 4 days.
Dobrev et al. (2007) also used corn cobs in medium composition for increasing
xylanase production by Aspergillus niger B03. The optimization process was performed. The fermentation was carrying out in flasks inoculated with 10% inoculums, cultivated at 28 °C for 64 h at 180 rpm shaking. The xylanase activity obtained
Exogenous Enzymes
both strains the maximum cellulasic activity occurred between 72 h and 96 h of
incubation at 30 °C.
Waseem et al. (2014) reported that CB-2 and CB-3 strains of Bacillus subtilis
were used for the flask-scale production of cellulase through submerged fermentation. Results revealed the highest cellulolytic activity (CMCase) with 120.321 U/ml
and filter paper activity (FPase) with 1.076 U/ml by CB-2 strain followed by CB-3.
Optimum temperature and pH of the medium for cellulase production was 37.5 °C,
pH and 9 respectively, with 2% untreated cotton stalk as carbon source, yeast as
organic nitrogen source and ammonium sulphate as inorganic nitrogen source with
3% inoculum size.
Ariffin et al. (2006) conducted a study to produce cellulase by local isolate
Bacillus pumilus EB3, using carboxymethyl cellulose (CMC)as substrate. Following
that, cellulase produced from Bacillus pumilus EB3 was purified using ion exchange
chromatography with anion exchanger (HiTrap QXL) for characterization of the
cellulase. Cellulase was successfully produced in 2 L stirred tank reactor (STR)
with the productivity of 0.53, 3.08 and 1.78 U/L h and the maximum enzyme activity of 0.011, 0.079 and 0.038 U/mL for FPase, CMCase and β-glucosidase, respectively. Purification of cellulase from Bacillus pumilus EB3 using ion exchange
chromatography showed that 98.7% of total CMCase was recovered.
Xylanases
Xylanase production has been documented in a wide spectrum of microorganisms,
including bacteria, actinomycetes, yeasts and filamentous fungi (Nascimento et al.
2003; Bakri et al. 2008). Studying the effect of orange pomace, orange peel, lemon
pomace, lemon peel, apple pomace, pear peel, banana peel, melon peel and hazelnut
shell on the production of xylanase, using Trichoderma harzianum 1073-D3, Seyis
and Aksoz (2005) discovered that molasses are able to reduce the time of production
in 50% when used as an additional carbon source. The maximum activity has been
observed on 2.5% melon peel medium (26.5 U mg
−1
of protein)incubated at 30 °C
for 7 days on a rotary shaker (150 rpm).
Rose and Van Zyl (2008) optimized xylanase production using a recombinant
strain of Aspergillus niger D15[xyn2]pyrG
−
. The highest xylanase activities of 226
and 209 U mL
−1
were produced with 20 and 30% molasses, respectively, at 30 °C,
pH 6.5, agitation of 100 rpm and a spore inoculum of 1.106 spores mL
−1
. In another
study Maciel et al. (2009) also produced xylanase with sugarcane bagasse under
SSF by Aspergillus niger LPB 326. The highest xylanase activity was 2327 U gdm
−1
using 65% of sugarcane bagasse and 35% of soybean meal supplemented with a
mineral salt solution, 85% initial moisture, 106 spores gdm
−1
,at 30 °C for 4 days.
Dobrev et al. (2007) also used corn cobs in medium composition for increasing
xylanase production by Aspergillus niger B03. The optimization process was performed. The fermentation was carrying out in flasks inoculated with 10% inoculums, cultivated at 28 °C for 64 h at 180 rpm shaking. The xylanase activity obtained
Exogenous Enzymes