Immobilization of Mushroom Tyrosinase by Different Methods in Order to Transform L-Tyrosine to L-3, 4 Dihydroxyphenylalanine (L-dopa)

Waste Management in the Agri-Food Industry: The Conversion of Eggshells, Spent Coffee Grounds, and Brown Onion Skins into Carriers for Lipase Immobilization

“…Cleaning of eggshells and removal of microorganisms is achieved by using dilute acid solutions such as acetic and hydrochloric acids. These procedures are most commonly used in the preparation of eggshells as a carrier for the immobilization of enzymes [65,[70][71][72][73]75,76]. However, the available literature does not provide data on the effect of different eggshell pretreatment methods (i.e., cooking in 0.1% sodium dodecyl sulphate solution or washing in acidic solutions) on enzyme immobilization efficiency.…”

“…However, the available literature does not provide data on the effect of different eggshell pretreatment methods (i.e., cooking in 0.1% sodium dodecyl sulphate solution or washing in acidic solutions) on enzyme immobilization efficiency. Research by Ribeiro et al [78], Salleh et al [75], Chattopadhyay and Sen [79], Norouizan et al [76], Vemuri et al [71], Venkaiah and Kumar [80], and Makkar and Sharma [70] indicates the potential of eggshells as carriers for enzyme immobilization after some degree of pretreatment. Immobilization of enzymes (urease, lipase, and tyrosinase) on eggshells was performed by adsorption [75], adsorption by sequential entrapment of the enzyme in a glutaraldehyde matrix [70,71], and adsorption on a polyethyleneimine-coated shell followed by entrapment of the enzyme with glutaraldehyde [76].…”

“…Research by Ribeiro et al [78], Salleh et al [75], Chattopadhyay and Sen [79], Norouizan et al [76], Vemuri et al [71], Venkaiah and Kumar [80], and Makkar and Sharma [70] indicates the potential of eggshells as carriers for enzyme immobilization after some degree of pretreatment. Immobilization of enzymes (urease, lipase, and tyrosinase) on eggshells was performed by adsorption [75], adsorption by sequential entrapment of the enzyme in a glutaraldehyde matrix [70,71], and adsorption on a polyethyleneimine-coated shell followed by entrapment of the enzyme with glutaraldehyde [76]. However, it is unlikely that they will find their way into commercial production as carriers in their intact form.…”

Biological sources of L-DOPA: An alternative approach

“…It lowers the production cost due to the reusability of the enzymes. The various techniques used for enzyme immobilization include entrapment in polymeric gels, adsorption onto insoluble materials, encapsulation in membranes, cross-linking with bifunctional or multifunctional reagents and linking to an insoluble carrier [16][17][18][19][20][21][22][23]. The substrate used for the synthesis of L-DOPA were catechol, sodium pyruvate and ammonium acetate.…”