322
The microbial production of protease by Bacillus Cereus using cassava waste
water was studied by (Santhi 2014) and it was reported that maximum protease
production was observed at 48 h with pH 7; increase in production was observed
when glucose and peptone were used as carbon and nitrogen sources in the production medium respectively. Further, cassava waste water was also used as an alternative carbon source for enzyme production, showing a maximum of protease
production when supplemented with 6% in the production medium.
An alkaline protease produced by a thermophilic bacteria Bacillus subtilisDM-04
was studied by Mukherjee et al. (2008) in SSF using potato peel (51.7% of carbon;
2.6% of nitrogen and 19.9% of C/N ratio) achieving 400 U gds
−1
. The higher alkaline protease (2382 U gds
−1
) was obtained with a mixture of potato peel and Imperata
cylindrica grass in the proportion 1:1 in tray-type bioreactor recovered with aluminum foil, incubated at 50 °C during 24 h. Low levels of acid and alkaline proteases
were produced during fermentation using residues (cassava peel, corn cob, corn
husk, oat husk and sugar cane bagasse) by Penicillium janthinellum CRC87M-115
(Oliveira et al. 2006). In another study alkaline protease production under SSF was
investigated using isolated alkalophilic Bacillus sp. and green gram husk as substrate. Maltose and yeast extract supplementation increased protease production.
The fermentation was conducted at 33 °C, pH 9.0, and moisture content (140%)
during 60 h. Protease activity reached more than 35,000 U g
−1
(Prakasham et al.
2006). Futhermore, SSF was conducted with rice bran and Rhizopus oligosporus
ACM 145F, incubated at 37 °C for 72 h, achieved a maximal production of an acid
protease (1.6 U mL
−1
) at pH 2.0, decreasing its activity in pH values above 5.0
(Ikasari and Mitchell 1996). In addition to this Pseudomonas aeruginosa was a
strain isolated from the tannery wastewater for its ability to produce alkaline protease (1160–1175 U mL
−1
) (Kumar et al. 2008).
Cellulases
Cellulases are inducible enzymes synthesized by a large diversity of microorganisms including both fungi andbacteria during their growth on cellulosic materials
(Kubicek 1993; Lee and Koo 2001). These microorganisms can be aerobic, anaerobic, mesophilic or thermophilic. Among them, the genera of Clostridium,
Cellulomonas, Thermomonospora, Trichoderma, and Aspergillus are the most
extensively studied cellulose producers (Sun and Cheng 2002; Kuhad et al. 1999).
Cellulolytic microbes are primarily carbohydrate degraders and are generally unable
to use proteins or lipids as energy sources for growth (Sukumaran et al. 2005).
Rodrigues (2011) reported that different concentrations of cellulose, ranging
from 20 g·L
−1
to 60 g·L
−1
, were assayed as the sole carbon source of the growth
medium of Aspergillus terreus A-1 and N-Y strains. The activity of cellulases produced by Aspergillus terreus A-1 strain had a maximum (13.2 U/mL) at the concentration of 30 g × L
−1
of cellulose. On the other hand, the maximum production of
cellulases by N-Y strain (10.2 U/mL) was obtained on 20 g × L
−1
of cellulose. For
S. Farooq et al.
The microbial production of protease by Bacillus Cereus using cassava waste
water was studied by (Santhi 2014) and it was reported that maximum protease
production was observed at 48 h with pH 7; increase in production was observed
when glucose and peptone were used as carbon and nitrogen sources in the production medium respectively. Further, cassava waste water was also used as an alternative carbon source for enzyme production, showing a maximum of protease
production when supplemented with 6% in the production medium.
An alkaline protease produced by a thermophilic bacteria Bacillus subtilisDM-04
was studied by Mukherjee et al. (2008) in SSF using potato peel (51.7% of carbon;
2.6% of nitrogen and 19.9% of C/N ratio) achieving 400 U gds
−1
. The higher alkaline protease (2382 U gds
−1
) was obtained with a mixture of potato peel and Imperata
cylindrica grass in the proportion 1:1 in tray-type bioreactor recovered with aluminum foil, incubated at 50 °C during 24 h. Low levels of acid and alkaline proteases
were produced during fermentation using residues (cassava peel, corn cob, corn
husk, oat husk and sugar cane bagasse) by Penicillium janthinellum CRC87M-115
(Oliveira et al. 2006). In another study alkaline protease production under SSF was
investigated using isolated alkalophilic Bacillus sp. and green gram husk as substrate. Maltose and yeast extract supplementation increased protease production.
The fermentation was conducted at 33 °C, pH 9.0, and moisture content (140%)
during 60 h. Protease activity reached more than 35,000 U g
−1
(Prakasham et al.
2006). Futhermore, SSF was conducted with rice bran and Rhizopus oligosporus
ACM 145F, incubated at 37 °C for 72 h, achieved a maximal production of an acid
protease (1.6 U mL
−1
) at pH 2.0, decreasing its activity in pH values above 5.0
(Ikasari and Mitchell 1996). In addition to this Pseudomonas aeruginosa was a
strain isolated from the tannery wastewater for its ability to produce alkaline protease (1160–1175 U mL
−1
) (Kumar et al. 2008).
Cellulases
Cellulases are inducible enzymes synthesized by a large diversity of microorganisms including both fungi andbacteria during their growth on cellulosic materials
(Kubicek 1993; Lee and Koo 2001). These microorganisms can be aerobic, anaerobic, mesophilic or thermophilic. Among them, the genera of Clostridium,
Cellulomonas, Thermomonospora, Trichoderma, and Aspergillus are the most
extensively studied cellulose producers (Sun and Cheng 2002; Kuhad et al. 1999).
Cellulolytic microbes are primarily carbohydrate degraders and are generally unable
to use proteins or lipids as energy sources for growth (Sukumaran et al. 2005).
Rodrigues (2011) reported that different concentrations of cellulose, ranging
from 20 g·L
−1
to 60 g·L
−1
, were assayed as the sole carbon source of the growth
medium of Aspergillus terreus A-1 and N-Y strains. The activity of cellulases produced by Aspergillus terreus A-1 strain had a maximum (13.2 U/mL) at the concentration of 30 g × L
−1
of cellulose. On the other hand, the maximum production of
cellulases by N-Y strain (10.2 U/mL) was obtained on 20 g × L
−1
of cellulose. For
S. Farooq et al.