compounds [49]. Protein hydrolysate produced by enzymatic hydrolysis of CTLS
wastes reacted with polyvinyl alcohol for producing biodegradable plastics [49].
9 Value-Added Product from Tannery Waste
Tannery wastes can be an important source of proteins and lipids, and there are
reports on efforts made to recover these biomolecules [50]. The decaying of proteins
and lipids is one of the major sources of offensive odours associated with tannery
waste due to oxidation of disulphide bridges in proteins and unsaturated fatty acids
present in these lipids. The protein-based components that can be recovered from
tannery waste include protein hydrolysates, peptides and amino acids, collagen and
gelatin and fish meal. The lipid-based compounds that can be recovered are oils,
omega-3 fatty acids, phospholipids, squalene, vitamins, cholesterol, etc. that are
required by many industries including food, agriculture, aquaculture and pharmaceuticals [51]. Proteinaceous fish meal is the main ingredient in fish feed formulation, because of its high protein content and an adequate profile of indispensable
amino acids which is a requirement for the growth of fish, especially the carnivorous
fish [52].
Tannery waste can also be utilized in the production of organic fertilizers and
composts which have significant benefits over chemical-based products. Potential
for biofuel recovery from such waste has been reported [53]. The recovery of
components with potential biological activities and functionalities provides a
means for value addition to the tannery processing waste and also adds to plant
economy. Currently, by-products from tannery processing if not dumped are used to
make low-valued products. Hides and skin from mature animals is tanned into
leather at a small percent for making different products. Fish frames and heads are
used for human consumption in the local community or used to make animal feeds
(at small scale). Oil obtained from the by-products can be utilized for value-added
products such as soap, biofuel and cosmetics.
10 Novel Biotechnological Approaches for Transforming
Tannery Waste into Bioproducts Using Biocatalysts
Today tannery biowaste poses environmental risks while being an important potential
feedstock resource for producing a wide range of bioproducts. The potential to exploit
tannery biowastes as a raw material for bioproducts/energy requires the application of
new technologies to arrive at novel and economically viable solutions. Enzymes are
becoming a key element in the toolbox for the chemist. In particular, biocatalytic
transformation of tannery waste is promising in production of bioproducts for use in
areas such as pharmaceutical and food chemicals where target molecules are selective
214
W. C. Wanyonyi and F. J. Mulaa
wastes reacted with polyvinyl alcohol for producing biodegradable plastics [49].
9 Value-Added Product from Tannery Waste
Tannery wastes can be an important source of proteins and lipids, and there are
reports on efforts made to recover these biomolecules [50]. The decaying of proteins
and lipids is one of the major sources of offensive odours associated with tannery
waste due to oxidation of disulphide bridges in proteins and unsaturated fatty acids
present in these lipids. The protein-based components that can be recovered from
tannery waste include protein hydrolysates, peptides and amino acids, collagen and
gelatin and fish meal. The lipid-based compounds that can be recovered are oils,
omega-3 fatty acids, phospholipids, squalene, vitamins, cholesterol, etc. that are
required by many industries including food, agriculture, aquaculture and pharmaceuticals [51]. Proteinaceous fish meal is the main ingredient in fish feed formulation, because of its high protein content and an adequate profile of indispensable
amino acids which is a requirement for the growth of fish, especially the carnivorous
fish [52].
Tannery waste can also be utilized in the production of organic fertilizers and
composts which have significant benefits over chemical-based products. Potential
for biofuel recovery from such waste has been reported [53]. The recovery of
components with potential biological activities and functionalities provides a
means for value addition to the tannery processing waste and also adds to plant
economy. Currently, by-products from tannery processing if not dumped are used to
make low-valued products. Hides and skin from mature animals is tanned into
leather at a small percent for making different products. Fish frames and heads are
used for human consumption in the local community or used to make animal feeds
(at small scale). Oil obtained from the by-products can be utilized for value-added
products such as soap, biofuel and cosmetics.
10 Novel Biotechnological Approaches for Transforming
Tannery Waste into Bioproducts Using Biocatalysts
Today tannery biowaste poses environmental risks while being an important potential
feedstock resource for producing a wide range of bioproducts. The potential to exploit
tannery biowastes as a raw material for bioproducts/energy requires the application of
new technologies to arrive at novel and economically viable solutions. Enzymes are
becoming a key element in the toolbox for the chemist. In particular, biocatalytic
transformation of tannery waste is promising in production of bioproducts for use in
areas such as pharmaceutical and food chemicals where target molecules are selective
214
W. C. Wanyonyi and F. J. Mulaa