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S. Majumdar and J. Bhowal
approach to decrease the production cost as well as to offer safe and better environment could be through the utilization of cheap, abundant and renewable lignocellulosic biomass, especially agricultural waste residues as nutrient source for the
polysaccharide-degrading enzyme-producing microbes. Although a variety of lignocellulosic substrates were tried for production of enzymes relevant to degradation of
lignocellulosic biomass (Sridevi et al. 2015), there is only a scanty published literature available on the use of cauliflower wastes (Dhillon et al. 2011). India is the
second-largest producer of cauliflower (Khedkar et al. 2017). Cauliflower has the
highest waste index (Stojceska et al. 2008) among the other vegetables belonging to
Brassicaceae family. Cauliflower wastes consist of good protein (16.1%), cellulose
(16%) and hemicelluloses (8%) (Wadhwa et al. 2015). Thus, besides the low cost
and higher biomass availability, cauliflower waste could serve as a very promising
substrate for microbial production of industrially important enzymes. The use of this
cheap agro-waste in the production of these enzymes will bring down their production
cost and at the same time reduce environmental pollution due to the wastes accumulation. Filamentous fungi produce appreciable levels of polysaccharide-degrading
enzymes (Ferreira et al. 2018). Aspergillus genus, namely, Aspergillus niger and
Aspergillus oryzae, are the two most important fungi frequently used in the release
of enzymes for degradation of recalcitrant biomass (Hu et al. 2011). Most literature
cited Candida albicans, Candida utilis, Candida lipolytica and other novel strains
capable of generating hydrolytic enzymes (Kuhad et al. 2011; Bansal et al. 2012). We
have not yet come across any published literature reporting commercial production of
cellulase and xylanase from Candida intermedia. This study is the first direct comparison of C. intermedia with two important enzyme-producing fungi A. niger and A.
oryzae. There has been an increasing interest in co-cultivation or synergistic action
of microbial strains for efficient metabolism of feedstock and release of enzymes in
substantial amount (Cavka and Jönsson 2014). In the present study, an attempt has
been made to utilize inexpensive and easily available agrowastes such as cauliflower
waste as substrate for enzymes production. Searching for new fungal strain suitable
for efficient production of industrially important enzymes is another objective of the
present study.
2 Materials and Methods
2.1 Microorganisms
Lyophilized three filamentous fungal strains Aspergillius oryzae MTCC 3782,
Aspergillus niger MTCC 9687 and Candida intermedia MTCC 1404 were purchased
from Microbial Type Culture Collection (MTCC, Chandigarh, India). A small amount
of pellet of each fungal strain was dissolved in 100 ml Erlenmeyer flasks containing
30 ml of sterilized growth medium (Czapek yeast extract agar, malt extract agar and
malt yeast extract agar for A. oryzae, A. niger and C. intermedia, respectively). All the
S. Majumdar and J. Bhowal
approach to decrease the production cost as well as to offer safe and better environment could be through the utilization of cheap, abundant and renewable lignocellulosic biomass, especially agricultural waste residues as nutrient source for the
polysaccharide-degrading enzyme-producing microbes. Although a variety of lignocellulosic substrates were tried for production of enzymes relevant to degradation of
lignocellulosic biomass (Sridevi et al. 2015), there is only a scanty published literature available on the use of cauliflower wastes (Dhillon et al. 2011). India is the
second-largest producer of cauliflower (Khedkar et al. 2017). Cauliflower has the
highest waste index (Stojceska et al. 2008) among the other vegetables belonging to
Brassicaceae family. Cauliflower wastes consist of good protein (16.1%), cellulose
(16%) and hemicelluloses (8%) (Wadhwa et al. 2015). Thus, besides the low cost
and higher biomass availability, cauliflower waste could serve as a very promising
substrate for microbial production of industrially important enzymes. The use of this
cheap agro-waste in the production of these enzymes will bring down their production
cost and at the same time reduce environmental pollution due to the wastes accumulation. Filamentous fungi produce appreciable levels of polysaccharide-degrading
enzymes (Ferreira et al. 2018). Aspergillus genus, namely, Aspergillus niger and
Aspergillus oryzae, are the two most important fungi frequently used in the release
of enzymes for degradation of recalcitrant biomass (Hu et al. 2011). Most literature
cited Candida albicans, Candida utilis, Candida lipolytica and other novel strains
capable of generating hydrolytic enzymes (Kuhad et al. 2011; Bansal et al. 2012). We
have not yet come across any published literature reporting commercial production of
cellulase and xylanase from Candida intermedia. This study is the first direct comparison of C. intermedia with two important enzyme-producing fungi A. niger and A.
oryzae. There has been an increasing interest in co-cultivation or synergistic action
of microbial strains for efficient metabolism of feedstock and release of enzymes in
substantial amount (Cavka and Jönsson 2014). In the present study, an attempt has
been made to utilize inexpensive and easily available agrowastes such as cauliflower
waste as substrate for enzymes production. Searching for new fungal strain suitable
for efficient production of industrially important enzymes is another objective of the
present study.
2 Materials and Methods
2.1 Microorganisms
Lyophilized three filamentous fungal strains Aspergillius oryzae MTCC 3782,
Aspergillus niger MTCC 9687 and Candida intermedia MTCC 1404 were purchased
from Microbial Type Culture Collection (MTCC, Chandigarh, India). A small amount
of pellet of each fungal strain was dissolved in 100 ml Erlenmeyer flasks containing
30 ml of sterilized growth medium (Czapek yeast extract agar, malt extract agar and
malt yeast extract agar for A. oryzae, A. niger and C. intermedia, respectively). All the