Layer-by-Layer coated tyrosinase: An efficient and selective synthesis of catechols

Abstract

a b s t r a c tAgaricus bisporous tyrosinase was immobilized on commercial available epoxy-resin Eupergit Ò C250L and then coated by the Layer-by-Layer method (LbL). The two novel heterogeneous biocatalysts were characterized for their morphology, pH and storage stability, kinetic properties (K m , V max , V max /K m ) and reusability. These biocatalysts were used for the efficient and selective synthesis of bioactive catechols under mild and environmental friendly experimental conditions. Ascorbic acid was added in the reaction medium to inhibit the formation of ortho-quinones, thus avoiding the known enzyme suicide inactivation process. Catechols were obtained mostly in quantitative yields and conversion of substrate. Tyrosinase immobilized on Eupergit Ò C250L and coated by the LbL method showed better catalytic activities, higher pH and storage stability, and reusability with respect to immobilized uncoated tyrosinase. Since chemical procedures to synthesize catechols are often expensive and with high environmental impact, the use of immobilized tyrosinase represents an efficient alternative for the preparation of this family of bioactive compounds.

Microbial Tyrosinases: Promising Enzymes for Pharmaceutical, Food Bioprocessing, and Environmental Industry

“…The two novel heterogeneous biocatalysts have been characterized for their morphology and reusability. These biocatalysts were used for the efficient and selective synthesis of bioactive catechols under mild and environmentally friendly experimental conditions [168]. Tyrosinase and layer-by-layer supported tyrosinases are also used in the synthesis of lipophilic catechols.…”

Naturally Occurring Hydroxytyrosol: Synthesis and Anticancer Potential

“…Once the desired concentration of HTyr was obtained, it was filtered; the enzyme was retained in the filter and reused again. Using a similar strategy, HTyr was synthesized from tyrosol using Agaricus bisporous tyrosinase immobilized on commercial available epoxy-resin Eupergit ® C250L and coated by the Layerby-Layer method (LbL) [28].…”

Kinetic characterization of tyrosinase containing mushroom (Agaricus bisporus) cells immobilized in silica alginate

“…Kinetic studies were carried out in glass vials by incubating 0.2 g matrix capsules (5-60 mg cdw/(ml polymer solution), N ≈ 200, r = 0.6 mm unless otherwise stated) with 3.8 ml BPA solution (2.1-438 mol/l) with a certain pH value (3)(4)(5)(6)(7)(8)(9)(10)(11) adjusted to with HCl or NaOH. Due to the high water content of the matrix capsules it was assumed that the BPA was diluted rapidly to a 4% lower concentration (2-420 mol/l, see Section 3.1 for details), which is considered as the initial BPA concentration reported in Section 3.2.…”

“…This reaction pattern has been examined for tyrosinase catalyzed production of various o-diphenols [3,4], among these the antioxidant hydroxytyrosol [5], 3,4-dihydroxyphenylacetic acid [4], a substance with antiproliferative activity against cancer cells [6], and 3,4-dihydroxy-l-phenylalanine (l-DOPA) [7][8][9] which is a prescribed drug for treatment of Parkinson's disease. The formation of the o-quinones in these reaction systems can be reduced by addition of ascorbic acid as a reducing agent [3][4][5][7][8][9].…”

“…The formation of the o-quinones in these reaction systems can be reduced by addition of ascorbic acid as a reducing agent [3][4][5][7][8][9].…”