Polyphenol oxidase from Black mulberrys was extracted and partially purified through (NH4)2SO4 precipitation, dialysis and ion exchange chromatography. P-cresol was the better substrate for cresolase activity with a Km (11.5 mM) and catechol for catecholase activity with Km (6.4 mM) at pH 5. Km for cresolase and catecholase activity of IsoPPOII at pH 6.5 were 12 and 8.5 and for IsoPPOIII at pH ...

Raw-starch-digesting enzyme (RSDA) was immobilized on Amberlite beads by conjugation of glutaraldehyde/ polyglutaraldehyde (PG)-activated beads or by crosslinking. The effect of immobilization on enzyme stability and catalytic efficiency was evaluated. Immobilization conditions greatly influenced the immobilization efficiency. Optimum pH values shifted from pH 5 to 6 for spontaneous crosslinkin...

A composite cathode based on redox-stable La0.2Sr0.8TiO(3+δ) (LSTO) can perform direct carbon dioxide electrolysis; however, the insufficient electro-catalytic activity limits the electrode performances and current efficiencies. In this work, catalytically active scandium is doped into LSTO to enhance the electro-catalytic activity for CO2 electrolysis. The structures, electronic conductivities...

Extracellular laccase was produced by Trametes versicolor IBL-04 using corn cobs as a substrate under pre-optimized culture conditions. A 64kDa laccase enzyme was purified and immobilized on calcium alginate beads using glutaraldehyde as a cross-linking reagent. Maximum enzyme immobilization efficiency (89%) was observed with 2-mm calcium-alginate beads that were developed using 4% (w/v) sodium...

Sites for Cys substitutions to form a disulfide bond were chosen in subtilisin E from Bacillus subtilis, a cysteine-free bacterial serine protease, based on the structure of aqualysin I of Thermus aquaticus YT-1 (a thermophilic subtilisin-type protease containing two disulfide bonds). Cys residues were introduced at positions 61 (wild-type, Gly) and 98 (Ser) in subtilisin E by site-directed mut...

An alcohol dehydrogenase (ADH) from hyperthermophilic archaeon Thermococcus guaymasensis was purified to homogeneity and was found to be a homotetramer with a subunit size of 40 ± 1 kDa. The gene encoding the enzyme was cloned and sequenced; this gene had 1,095 bp, corresponding to 365 amino acids, and showed high sequence homology to zinc-containing ADHs and l-threonine dehydrogenases with bin...

Keratinases are a group of proteolytic enzymes that display the capability of degrading insoluble keratin substrates such as feather resulting as poultry waste. Entrapment of crude/purified enzyme within a matrix is a common method for immobilization. An immobilized enzyme provides increased resistance to changes in conditions such as pH or temperature. It also allows enzymes to be held in plac...

Attempts have been made to optimize immobilization parameters, catalytic property, and stability of immobilized α-amylase in agar. The work compares natural entrapment efficiency of agar with the ionotropically cross-linked agar hydrogel, with the advantage of easy scale-up and cost and time effectiveness. Beads prepared with 3% (w/v) agar and 75 mM calcium chloride and hardened for 20 minutes ...

The aim of the present study was to evaluate the impacts of diets supplemented with different lipid sources on growth performance, body composition, fatty acid profile, and hepatic antioxidant enzyme activity of juvenile black sea bream, Acanthopagrus schlegeli (initial mean weight, 1.1±0.02g). Four isonitrogenous and isolipidic diets were formulated with either fish oil (FO), soybean oil (SO),...

The aim of the present study was to evaluate the impacts of diets supplemented with different lipid sources on growth performance, body composition, fatty acid profile, and hepatic antioxidant enzyme activity of juvenile black sea bream, Acanthopagrus schlegeli (initial mean weight, 1.1±0.02g). Four isonitrogenous and isolipidic diets were formulated with either fish oil (FO), soybean oil (SO),...