Under the condition of equal nutritional level, a study was conducted to investigate the effects of different dietary wheat bran levels (0%,3%,6%,9%) and 9% wheat bran plus 500IU/Kg microbial phytase on productive performance, utilization of main nutrients and tibia parameters in broilers.
In order to investigate the effects of microbial phytase(MP)or wheat bran(WB)on the phytate phosphorus availability48(Landrace × Meishan)×(Hampshire × Meishan)piglets were used in a feeding trial from 11.0(±0.24kg)to 90kg BW,with 11 to 50kg,50 to 90 as phase 1 and phase 2,respectively.
While in groups 2, 3, 4 and 5, broilers were fed on low-P basal diets, in which microbial phytase was added at the concentrations of 0, 350, 500 and 650 phytase units per kilogram of the diets respectively.
To investigate the effects of supplemental microbial phytase (Natuphos 5 000) in diets on performance and mineral excretion, fifty-threemonth old healthy rex-rabbits with similar weight was assigned randomly into 5 groups for a 6-week trial.
Studies on the partial enzyme characters of recombinant phytase showed that the recombinant phytase had two pH optima (2.5-3.0 and 5.0-5.5) and a temperature optimum 55℃, and with higher activity under the pH ranged from 4.5 to 6.0. The result of SDS-PAGE indicated that the molecular weight of the recombinant phytase is between 70kDa-97kDa.
crassa phy was also cloned as an EcoR I fragment into the corresponding site of the expression vector pPIC9K downstream of the AOX1 promoter. The resulting plasmid pPIC9K-phy was linearized with Nco I endoenzyme and subsequently electrotransformed into P. pastoris KM71. The recombinant phytase was purified as follows.
Four hundred seven-day old Avian broiler chickens were used to evaluate the effect of 0,300,600 and 900 IU/kg recombinant phytase on the performance and phosphorus utilization in comparison with dicalcium phosphate supplemented diet.
Phytase genephyA2, whose signal peptide encoding sequence and intron sequence had been removed, was modified.
The result of SDS-PAGE of the phytase expressed by P.pastoris showed that the modifiedphyA2 had been overexpressed and secreted.
The concentration of the phytase expressed by P.pastoris with modifiedphyA2 exceeded 15 000 U/mL, which had a 3 000-fold increase over that of originAspergillus niger 963 and was 37 times higher than that of recombinantP.
In this paper, progresses in researches on physiology of Zn deficiency in animals, phytate effect on bioavailability of Zn, and role of phytase in healing Zn deficiency of animals were reviewed.
Enhancement of zinc utilization from phytate-rich soy protein isolate by microbial phytase
A study with three groups, each with 11 male, individually housed albino rats (initial average weight=50 g) was undertaken to examine the effect of microbial phytase (added to a diet containing phytate) on the availability of zinc.
In groups II (pair-fed to group I) and III, 1 000 U of microbial phytase (Aspergillus niger var.
Dietary effect of phytogenic phytase and an addition of microbial phytase to a diet based on field beans, wheat, peas and barley
In group II, 350 U, in group III, 700 U of microbial phytase per kg diet were added.
The recombinant phytase had one optimum pH (pH?4.5) and an optimum temperature of 50°C.
Phytase expression in transgenic plant was enhanced with a synthetic phytase gene according to the Brassica codon usage and an endoplasmic reticulum (ER) retention signal KDEL that confers an ER accumulation of the recombinant phytase.
These results suggest a commercial feasibility of producing a stable recombinant phytase in canola at a high level for animal feed supplement and for reducing phosphorus eutrophication problems.
Detailed analysis of immature seeds by immunofluorescence and electron microscopy showed that recombinant phytase carrying a signal peptide for entry into the endoplasmic reticulum was efficiently secreted from storage cotyledon cells.
The medium for recombinant phytase production by E.