title: Increase of the phytase production by Aspergillus japonicus and its biocatalyst potential on chicken feed treatment.
abstract: Phytase hydrolyzes phytic acid from the plant components of animal feed, releasing inorganic phosphorus. The phytase production by Aspergillus japonicus was optimized using Plackett-Burman designs (PBD), composite central rotational designs (CCRD), and response surface methodology from standard Czapek medium. The enzyme was applied in broiler chicken and laying hen foods. Analysis from PBD showed that KH2 PO2, MgSO4  · 7H2O, and yeast extract had significant influences on phytase secretion (p < 0.05). The best results from the CCRD experiments were obtained using (A) 0.040% KH2 PO4, (B) 0.050% MgSO4  · 7H2O, and (C) 0.040% yeast extract, enhancing in 49-53 U mg(-1) protein. The determination coefficient (R(2)) was 0.92 and Fcalc was 7.48 times greater than Flisted . Thus, the reduced coded model: Y (U mg-1) = 50.29 + 4.30A - 3.35(A)2 - 4.80(B)2 + 5.62C - 4.26(C)2 was considered predictive and statistically significant (p < 0.05). The optimized culture medium increased the phytase yield in 250%. A. japonicus phytase released high levels of Pi from broiler chicken and laying hen food. A. japonicus is an excellent phytase producer in a culture medium using inexpensive components and agricultural wastes. Therefore, these results provide sound arguments for the formulation of a low cost culture medium for phytase production.
authors.affiliation: Department of Biochemistry and Immunology, São Paulo University, Ribeirão Preto, SP, Brazil.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Maller
authors.forename: Ana Claudia
authors.initials: AC
authors.lastname: Vici
authors.forename: Fernanda Del Antonio
authors.initials: Fdel A
authors.lastname: Facchini
authors.forename: Tony Marcio
authors.initials: TM
authors.lastname: da Silva
authors.forename: Eliana Setsuko
authors.initials: ES
authors.lastname: Kamimura
authors.forename: Maria Isabel
authors.initials: MI
authors.lastname: Rodrigues
authors.forename: João Atílio
authors.initials: JA
authors.lastname: Jorge
authors.forename: Hector Francisco
authors.initials: HF
authors.lastname: Terenzi
authors.forename: Maria
authors.initials: M
authors.lastname: de Lourdes Teixeira de Moraes Polizeli
mesh_terms: D010832:6-Phytase / Q000378:metabolism*; D000821:Animal Feed; D000818:Animals; D001230:Aspergillus / Q000201:enzymology* / Q000254:growth & development; D002645:Chickens; D003470:Culture Media / Q000737:chemistry; D004798:Enzymes / Q000378:metabolism; D005511:Food Handling / Q000379:methods
chemical_list: D003470:Culture Media; D004798:Enzymes; D010832:6-Phytase
keywords: Aspergillus japonicus; Biocatalyst potential; Chicken feed; Formulation of a culture medium; Phytase