title: Impact of microbial growth inhibition and proteolytic activity on the stability of a new formulation containing a phytate-degrading enzyme obtained from mushroom.
abstract: The development of stable enzymes is a key issue in both the food and feed industries. Consequently, the aim of the current study is to evaluate the impact of various additives (sodium chloride, sodium citrate, mannitol, methylparaben, polyethylene glycol 3350, ethylenediaminetetraacetic acid disodium salt, and a serine protease inhibitor) on the stability of a mushroom phytase produced by solid-state cultivation and recovery. Also observed was the effect of the additives on microbial growth inhibition by monitoring both the change in optical density over 30 days of storage and proteolytic activity. Initially, eight experimental formulations were prepared along with a control. After screening, a 3(2) factorial design was applied to define suitable concentrations of the selected additives. Among the eight formulations tested, the formulation containing NaCl, PEG 3350, and methylparaben retained all of the initial phytase activity after 50 days of storage, with no detected interference from protease activity. Sodium citrate, a metal chelation agent, presented the unusual effect of reducing protease activity in the formulations. Although all formulations presented better phytase stability when compared to the control, NaCl and PEG were both able to prolong the stability of the enzyme activity and also to inhibit microbial growth during storage, making them favorable for application as food and feed additives.
authors.affiliation: a Chemical Engineering Department, Food Engineering Post Graduate Program , Federal University of Paraná , Curitiba , Paraná State , Brazil.
authors.forename: Michele R
authors.initials: MR
authors.lastname: Spier
authors.affiliation: a Chemical Engineering Department, Food Engineering Post Graduate Program , Federal University of Paraná , Curitiba , Paraná State , Brazil.
authors.forename: Francieli B
authors.initials: FB
authors.lastname: Siepmann
authors.affiliation: b Bioprocess Engineering and Biotechnology Department , Federal University of Paraná , Curitiba , Paraná State , Brazil.
authors.forename: Larissa
authors.initials: L
authors.lastname: Staack
authors.affiliation: b Bioprocess Engineering and Biotechnology Department , Federal University of Paraná , Curitiba , Paraná State , Brazil.
authors.forename: Priscila Z
authors.initials: PZ
authors.lastname: Souza
authors.affiliation: c Division of Aquaculture, College of Agriculture, Food Science and Sustainable Systems , Kentucky State University , Frankfort , Kentucky , USA.
authors.forename: Vikas
authors.initials: V
authors.lastname: Kumar
authors.affiliation: b Bioprocess Engineering and Biotechnology Department , Federal University of Paraná , Curitiba , Paraná State , Brazil.
authors.forename: Adriane B P
authors.initials: AB
authors.lastname: Medeiros
authors.affiliation: b Bioprocess Engineering and Biotechnology Department , Federal University of Paraná , Curitiba , Paraná State , Brazil.
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Soccol
mesh_terms: D010832:6-Phytase / Q000378:metabolism*; D000363:Agaricales / Q000201:enzymology*; D004339:Drug Compounding; D010833:Phytic Acid / Q000378:metabolism*; D059748:Proteolysis
chemical_list: D010833:Phytic Acid; D010832:6-Phytase
keywords: Additives; Ganoderma sp.; enzyme stability; formulations; mushroom; phytate-degrading enzyme