Stein and his team at the U of I have recently published results indicating that a new microbial phytase derived from the bacterium Aspergillus oryzae is highly effective at releasing phosphorus from the phytate molecule.
"There are many microbial phytases on the market, and companies are constantly developing new ones to try to release more phosphorus from the phytate molecule," Stein said. "Some are E. coli based, and some are based on other microbes. This particular enzyme is based on Aspergillus oryzae, and this is the first time we have worked with it."
In the study, pigs were fed diets based on corn and soybean meal. The positive control diet had dicalcium phosphate and limestone added. The negative control diet contained no microbial phytase and no dicalcium phosphate, and experimental diets were formulated by adding 500, 1,000, 2,000, or 4,000 phytase units, respectively, to the negative control diet. Two experiments were conducted: one using weanling pigs (average initial body weight: 13.5 kg) and one using growing pigs (average initial body weight: 36.2 kg).
Stein explained that when the negative control diet was fed to weanling pigs, the apparent total-tract digestibility (ATTD) of phosphorus was 40.5 percent. The ATTD of phosphorus increased as phytase was added to the diet, to a maximum of 68.7 percent. A broken line analysis was then performed to determine the optimal phytase level. The breakpoint was at 1,016 phytase untis, with an ATTD of 68.4 percent. This compared favorably to the ATTD of phosphorus in the positive control diet, which was 60.5 percent. For growing pigs, the ATTD of phytase was 39.8 percent for the negative control diet, 59.4 percent for the positive control diet, 72.8 percent at 4,000 phytase units, and 69.1 percent at the breakpoint level of 801 phytase units.
Calcium digestibility was also improved by adding microbial phytase to the negative control diet, he said. In weanling pigs, the ATTD of calcium increased from 63.9 percent in the negative control to 84.7 percent at the optimal phytase level of 1,155 phytase units. In growing pigs, the ATTD of calcium increased from 67.3 percent in the negative control to 83.5 percent at the optimal phytase level of 574 phytase units.
"Because we did not compare this phytase to other microbial phytases, we cannot say whether or not this is as good as or better than some of the other commercial phytases, but this is a very effective phytase," Stein added.
The new Aspergillus oryzae-based phytase, Ronozyme HiPhos, is produced in Denmark, and has been approved for use in Europe and the United States, where it is marketed by DSM Nutritional Products.
The study, "Effects of a novel bacterial phytase expressed in Aspergillus oryzae on digestibility of calcium and phosphorus in diets fed to weanling or growing pigs," was published in the Journal of Animal Science and Biotechnology and is available online at http://www.jasbsci.com/content/4/1/8. Ferdinando Almeida, a Ph. D. candidate in the Stein Monogastric Nutrition Laboratory at Illinois, and Rommel Sulabo of the National University of the Philippines were co-authors of the study.
Stephanie Henry | EurekAlert!
Plasma-zapping process could yield trans fat-free soybean oil product
02.12.2016 | Purdue University
New findings about the deformed wing virus, a major factor in honey bee colony mortality
11.11.2016 | Veterinärmedizinische Universität Wien
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy