Thus the objective of this study was to investigate the effect of microbial 6-phytase on growth performance, apparent nutrient digestibility, chemical traits of tibia, plasma parameters and apparent ileal AA digestibility in Youxian Sheldrakes fed a low-phosphorus corn-soybean diet.
In this study, phytase (Escherichia coli 6-phytase) was added at a concentration of 5,000 U/kg.
Two independent experiments were conducted in the Biochemistry Laboratory of the Chemistry Department of the Federal University of Lavras with two powdered enzymes: a) 6-phytase
EC 18.104.22.168 (synthesized by Aspergillus oryzae genetically modified by addition of the gene from the Peniophora lycii) and b) 3-phytase EC 22.214.171.124 (produced by A.
The phytase used in the present study is a novel bacterial-derived 6-phytase
expressed in Psedomonas fluorescens and to the best of our knowledge, no data is available demonstrating its efficacy in improving P digestibility in feed ingredients commonly fed to pigs.
The efficacy of graded levels of a new 6-phytase
from Buttiauxella spp.
utilized in this study (EC 126.96.36.199 synthesized by Aspergillus oryzae) was a powder commercial product marketed by DSM Company, with determined activity of 9,980 FTU/g of product, according to the protocol of Engelen et al.
These HAP enzymes are specific in the way they attack phytic acid: they are either 3-phytases which remove the phosphate from position 3 first, or are 6-phytases
which first remove that in the 6-position.
Plant phytases act at the C6 position, and are called 6-phytases
. Some bacteria such as Escherichia-coli also act to break down phytate, but do not fit within these two categories.
A study conducted by Wodzinski and Ullah (1996) also reported that 6-phytases
such as ECP would completely dephosphorylate the phytate molecule, whereas 3-phytases such as ANP do not due to their respective initiation sites.