because of the associated reductions in energy consumption and costs as well as to
protect texture and colors of the fabrics (Davail et al. 1994; Mohammed et al. 2012).
Therefore, subtilisins currently incorporated in cold-active detergents are engineered
enzymes that combine storage stability, alkaline stability and activity, and cold
activity. Although psychrophilic subtilisins are not components of cold-active
detergents, they can largely contribute to the advancement of this economically
attractive concept. Besides this cold-active microbial α-amylases indicates the
potential of this enzymes as a detergent additive for cold washing that may be useful
for domestic processes (Mohammed et al. 2012). Therefore, lowering the wash
temperature by using cold-active enzymes can reduce energy consumption and
may be used to protect environment because these are biodegradable.
6.14.1.2 Food and Pharmaceutical Industry
The cold-active xylanase from the Antarctic bacterium Pseudoalteromonas
haloplanktis is a nice example of the successful biotechnological transfer from
academic research to industry. Xylanases are glycoside hydrolases that degrade the
polysaccharide beta-1, 4-xylan, thus breaking down hemicellulose, one of the major
components of plant cell walls. Xylanases are also a key ingredient of industrial
dough conditioners used to improve bread quality (De-Vos et al. 2006). Furthermore, baking trials have revealed that the psychrophilic xylanase was very effective
in improving the dough properties and final bread quality with, for instance, a
positive effect on loaf volume (Collins et al. 2006). This efficiency appears to be
related to the high activity of the psychrophilic xylanase at cool temperatures
required for dough resting and to its specific mode of xylan hydrolysis. Following
careful production optimization of this peculiar xylanase, the product is now sold by
Puratos (Belgium). This is apparently the psychrophilic enzyme produced at the
highest amounts at present time (Margesin and Feller 2010).
Beta-galactosidase, or lactase, is also a glycoside hydrolase that specifically
hydrolyzes the milk sugar lactose into galactose and glucose. It should be stressed
that 75% of the world population suffers from lactose intolerance arising from
deficient synthesis of intestinal lactase in adults and resulting in digestive disorders
due to fermentation of lactose by enteric bacteria. In this context, a cold-active
lactase from an Antarctic bacterium has been patented (WO 01/04276A1) for its
capacity to hydrolyze lactose during milk storage at low temperatures (Hoyoux et al.
2001). It is worth mentioning that commercially available lactases require milk
heating to become active. This heating step has, however, detrimental effects on
milk quality as it alters the aspect, the taste, and texture (Maillard reactions, activation of proteases, coagulation, and so on). Although the psychrophilic lactase is
apparently not used for this specific application, it is expected that many industries
will be produced soon in large quantities to hydrolyze lactose (a by-product of the
dairy industry) in the process of the high value sweetener D-tagatose, a natural
monosaccharide with low caloric value and glycemic index (Margesin and Feller
2010).
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P. K. Mishra et al.
protect texture and colors of the fabrics (Davail et al. 1994; Mohammed et al. 2012).
Therefore, subtilisins currently incorporated in cold-active detergents are engineered
enzymes that combine storage stability, alkaline stability and activity, and cold
activity. Although psychrophilic subtilisins are not components of cold-active
detergents, they can largely contribute to the advancement of this economically
attractive concept. Besides this cold-active microbial α-amylases indicates the
potential of this enzymes as a detergent additive for cold washing that may be useful
for domestic processes (Mohammed et al. 2012). Therefore, lowering the wash
temperature by using cold-active enzymes can reduce energy consumption and
may be used to protect environment because these are biodegradable.
6.14.1.2 Food and Pharmaceutical Industry
The cold-active xylanase from the Antarctic bacterium Pseudoalteromonas
haloplanktis is a nice example of the successful biotechnological transfer from
academic research to industry. Xylanases are glycoside hydrolases that degrade the
polysaccharide beta-1, 4-xylan, thus breaking down hemicellulose, one of the major
components of plant cell walls. Xylanases are also a key ingredient of industrial
dough conditioners used to improve bread quality (De-Vos et al. 2006). Furthermore, baking trials have revealed that the psychrophilic xylanase was very effective
in improving the dough properties and final bread quality with, for instance, a
positive effect on loaf volume (Collins et al. 2006). This efficiency appears to be
related to the high activity of the psychrophilic xylanase at cool temperatures
required for dough resting and to its specific mode of xylan hydrolysis. Following
careful production optimization of this peculiar xylanase, the product is now sold by
Puratos (Belgium). This is apparently the psychrophilic enzyme produced at the
highest amounts at present time (Margesin and Feller 2010).
Beta-galactosidase, or lactase, is also a glycoside hydrolase that specifically
hydrolyzes the milk sugar lactose into galactose and glucose. It should be stressed
that 75% of the world population suffers from lactose intolerance arising from
deficient synthesis of intestinal lactase in adults and resulting in digestive disorders
due to fermentation of lactose by enteric bacteria. In this context, a cold-active
lactase from an Antarctic bacterium has been patented (WO 01/04276A1) for its
capacity to hydrolyze lactose during milk storage at low temperatures (Hoyoux et al.
2001). It is worth mentioning that commercially available lactases require milk
heating to become active. This heating step has, however, detrimental effects on
milk quality as it alters the aspect, the taste, and texture (Maillard reactions, activation of proteases, coagulation, and so on). Although the psychrophilic lactase is
apparently not used for this specific application, it is expected that many industries
will be produced soon in large quantities to hydrolyze lactose (a by-product of the
dairy industry) in the process of the high value sweetener D-tagatose, a natural
monosaccharide with low caloric value and glycemic index (Margesin and Feller
2010).
210
P. K. Mishra et al.