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Query: EC:3.1.3.8 (
phytase
)
1,997
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The effects of microbial
3-phytase
and glycosidase enzymes, and their interactions, on energy values and nutrient digestibility in diets rich in nonstarch polysaccharides (NSP) were studied in diets based on corn, wheat, or barley. Four diets were prepared with each cereal grain. One had no enzymes, a second had 500 units of
phytase
, a third had glycosidase enzyme, and a fourth had
phytase
and glycosidase. The glycosidases used were alpha-galactosidase (corn diet), xylanase (wheat), and beta-glucanase (barley). Glycosidase decreased intestinal viscosity, whereas
phytase
increased this parameter in corn diets. Phytase increased AME in corn diets, whereas beta-glucanase in barley diets improved AME and AMEn, and digestibility of dry matter, starch, beta-glucans, and lipid. Xylanase in wheat diets improved dry matter and starch digestibility. Phytase increased total phosphorus retention in all diets, and significant interactions between glycosidase enzymes and
phytase
were detected in wheat and barley diets. Phytase decreased phosphorus excretion in corn and barley diets, whereas alpha-galactosidase increased phosphorus excretion in corn diets. Phytase in corn diets and beta-glucanase in barley diets increased
calcium
retention, whereas inclusion of xylanase decreased
calcium
retention in wheat diets. Phytase and beta-glucanase decreased
calcium
excretion in corn- and barley-based diets, respectively. An interaction was detected between
phytase
and beta-glucanase in barley diets, in which
calcium
excretion was reduced. In general, no negative interactions between
phytase
and glycosidase enzymes were found, indicating that both types of enzymes may be used together in feeds based on corn, wheat, or barley.
...
PMID:Assessment of potential interactions between phytase and glycosidase enzyme supplementation on nutrient digestibility in broilers. 1584 13
A 24-week performance trial was conducted to evaluate the efficacy of an experimental
phytase
on performance, egg quality, tibia ash content and phosphorus excretion in laying hens fed on either a maize- or a barley-based diet. At the end of the trial, an ileal absorption assay was conducted in order to determine the influence of
phytase
supplementation on the apparent absorption of
calcium
and total phosphorus (P). Each experimental diet was formulated either as a positive control containing 3.2 g/kg non-phytate phosphorus (NPP), with the addition of dicalcium phosphate (DCP), or as a low P one, without DCP addition. Both low P diets (containing 1.3 or 1.1 g/kg NPP) were supplemented with microbial
phytase
at 0, 150, 300 and 450 U/kg. The birds were housed in cages, allocating two hens per cage as the experimental unit. Each of 10 dietary treatments was assigned to 16 replicates. Low dietary NPP (below 1.3 g/kg) was not able to support optimum performance of hens during the laying cycle (from 22 to 46 weeks of age), either in maize or barley diets. Rate of lay, daily egg mass output, feed consumption, tibia ash percentage and weight gain were reduced in hens fed low NPP diets. The adverse effects of a low P diet were more severe in hens on a maize diet than in those on a barley diet. Low dietary NPP reduced egg production, weight gain, feed consumption and tibia ash content and microbial
phytase
supplementation improved these parameters. Hens given low NPP diets supplemented with
phytase
performed as well as the hens on positive control diets containing 3.2 g/kg of NPP. A 49% reduction of excreta P content was achieved by feeding hens on low NPP diets supplemented with
phytase
, without compromising performance. Phytase addition to low NPP diets increased total phosphorus absorption at the ileal level, from 0.25 to 0.51 in the maize diet and from 0.34 to 0.58 in the barley diet. Phosphorus absorption increased linearly with increasing levels of dietary
phytase
. Mean phosphorus absorption was higher in barley diets than in maize diets (0.49 vs 0.39).
...
PMID:Effects of an experimental phytase on performance, egg quality, tibia ash content and phosphorus bioavailability in laying hens fed on maize- or barley-based diets. 1605 Jan 88
The waste tea fungal biomass produced during black tea fermentation was investigated as a dietary ingredient in poultry feeds. A small portion of fungal mat was used as starter culture for the next cycle while the major portion is discarded as waste. Hence a trial study was carried out to utilize the waste fungal biomass as a supplementary diet for broiler chicks. The fungal biomass contained 179.38 g of crude protein, 120 g crude fibre, 4.82 g phosphorus, 6.56 g of
calcium
and 8.92 MJ metabolizable energy per kilogram of biomass. The dried tea fungus showed
phytase
activity of 23 IU/mg protein. The supplementation of tea fungal inclusion (TFI) at 150 g/kg concentration in poultry feed increased the feed consumption, body weight, performance efficiency factor (PEF) and the carcass characters of test broilers significantly (P=0.01) over the control. The histopathological examination of liver showed no abnormalities and the mortality rate was zero.
...
PMID:Supplementation of waste tea fungal biomass as a dietary ingredient for broiler chicks. 1605 Oct 80
Phytases catalyze the hydrolysis of phytic acid (InsP6, myo-inositol hexakisphosphate), the most abundant inositol phosphate in cells. In cereal grains and legumes, it constitutes 3-5% of the dry weight of seeds. The inability of humans and monogastric animals such as swine and poultry to absorb complexed InsP6 has led to nutritional and environmental problems. The efficacy of supplemental phytases to address these issues is well established; thus, there is a need for phytases with a range of biochemical and biophysical properties for numerous applications. An alkaline
phytase
that shows unique catalytic properties was isolated from plant tissues. In this paper, we report on the biochemical properties of an alkaline
phytase
from pollen grains of Lilium longiflorum. The enzyme exhibits narrow substrate specificity, it hydrolyzed InsP6 and para-nitrophenyl phosphate (pNPP). Alkaline
phytase
followed Michaelis-Menten kinetics with a K(m) of 81 microM and V(max) of 217 nmol Pi/min/mg with InsP6 and a K(m) of 372 microM and V(max) of 1272 nmol Pi/min/mg with pNPP. The pH optimum was 8.0 with InsP6 as the substrate and 7.0 with pNPP. Alkaline
phytase
was activated by
calcium
and inactivated by ethylenediaminetetraacetic acid; however, the enzyme retained a low level of activity even in
Ca2+
-free medium. Fluoride as well as myo-inositol hexasulfate did not have any inhibitory affect, whereas vanadate inhibited the enzyme. The enzyme was activated by sodium chloride and potassium chloride and inactivated by magnesium chloride; the activation by salts followed the Hofmeister series. The temperature optimum for hydrolysis is 55 degrees C; the enzyme was stable at 55 degrees C for about 30 min. The enzyme has unique properties that suggest the potential to be useful as a feed supplement.
...
PMID:Alkaline phytase from lily pollen: Investigation of biochemical properties. 1605 Nov 82
Phytase (myo-inositol-1,2,3,4,5,6-hexakisphosphate phosphohydrolase, EC 3.1.3.26) catalyses the stepwise hydrolysis of phytic acid (myo-inositol hexakisphosphate). Phytases are of great commercial importance due to their usage as supplement of food and animal feed, which can cater to nutrition demands and alleviate environmental problems, has been approved by many countries. Although acid phytases have been extensively studied, information regarding the phytases from Citrobacter is limited. In the work presented, a
phytase
was separated from Citrobacter freundii. After steps of electrophoretic homogeneity by successive ammonium sulfate between 60% and 80% saturation precipitation, DEAE-Sepharose ion-exchange chromatography and gel filtration through Superdex HR 10/30, final gel elution resulted in a 41.3-fold purification and yield of 9.3%. Gel elution is an effective method to purify the protein which contaminated with a few other proteins. The purified preparations were used in subsequent characterization studies. Based on SDS-PAGE analysis, the molecular weight of the purified
phytase
was calculated to be approximately 45.0kDa in monomeric form. The pure enzyme has an optimum pH of 4.0 to approximately 4.5. It was found stable between pH5.0 to approximately 7.0, about 90% of the enzyme activity was retained at 37 degrees C for 60min. The
phytase
has an optimum temperature of 40 degrees C which was lower than that of other phytases from Aspergillus or E. coli (average 50 to approximately 60 degrees C) and was close to the temperature of gastrointestinal tract in animals (37 to approximately 40 degrees C). Thus the enzyme is a promising candidate for animal feed applications. Activity of the purified
phytase
was influenced by changing the reaction temperature. Data showed that the enzyme retained its activity over a long period when stored at 4 degrees C, whereas thermal inactivation studies indicated that the enzyme lost 100% activity after treatment at 60 degrees C for 4min. The Km values of the
phytase
for dodecasodium phytate at 37 degrees C was 0.85nmol/L with a Vmax 0.53IU/(mg x min). Phytase activity was strongly inhibited by SDS, Zn2+ and moderately inhibited by Cu2+, Cr3+, Fe2+ and Fe3+. Activity was not significantly affected by EDTA, K+, Mg2+ and
Ca2+
. The
phytase
has excellent resistance to trypsin, but not pepsin. The N-terminal amino acids sequence of the
phytase
protein was determined as QCAPEGYQLQQVLMM which exhibited about 80% homology to Glucose-1-phosphatases from E. coli, Shigella flexneri and Salmonella, whereas it did not show apparent sequence similarity with any other
phytase
listed in the databases. Initial characterization of the purified enzyme suggested that it is a potential candidate for use as an animal feed supplement.
...
PMID:[Purification and properties of Citrobacter freundii phytase]. 1657 82
Alkaline
phytase
activity, with a pH optimum of 8, was recovered from detergent extracts of dormant seeds of nine varieties of Phaseolus vulgaris L., Pisum sativum L. var. Early Alaska, and Medicago sativa L. This alkaline
phytase
of legume seeds was activated by
calcium
and differed from most seed phytases in its relative insensitivity to inhibition by fluoride.
...
PMID:Alkaline phytase activity in nonionic detergent extracts of legume seeds. 1666 29
1. The objective was to study the effects of a supplementation of a 6-
phytase
derived from the Peniophora lycii gene in the White Pekin duck. 2. In two balance studies, low-phosphorus (P) diets consisting mainly of maize, solvent extracted soybean meal and solvent extracted sunflower meal were supplemented with
phytase
up to concentrations of 1500 U/kg (Study 1) or 2000 U/kg (Study 2). Each diet (
phytase
level) was fed to 8 to 10 individually penned ducks. The intake and excretion of each animal was measured for 5 consecutive days when ducks were in their third week of life. Responses were described by nonlinear regression. 3. Although the basal diets from the two studies were similar in ingredient composition, efficiencies of P utilisation (P accretion/P intake x 100) for the unsupplemented basal diets were 39% in Study 1 and 30% in Study 2. Phytase supplementation significantly improved P utilisation up to levels of about 55% in both studies. A plateau in P utilisation with an increase in
phytase
supplementation was achieved in Study 2, but not in Study 1. The enzyme was more efficient in Study 2 than in Study 1 at low rates of supplementation. Utilisation of
calcium
(Ca) was significantly improved by
phytase
supplementation. Accretions of P and Ca increased at a constant ratio. 4. In a 5-week growth study, diets with an intentionally marginal P level were used. Diets were fed either unsupplemented or supplemented with 1000 or 10,000 U/kg of
phytase
. Eight pens of 10 sex-separated ducks each (4 pens per sex) were allocated to each dietary treatment. 5. Phytase significantly improved the growth of ducks of both sexes between d 1 and 21, but not between d 22 and 35. Feed conversion rate was not affected by treatment. Blood serum phosphate concentrations, but not
calcium
, were significantly increased by
phytase
supplementation. Blood concentrations of creatinine, aspartate aminotransferase and lactate dehydrogenase remained unaffected while alanine aminotransferase was significantly reduced by
phytase
supplementation. 6. It was concluded that the efficacy of a microbial
phytase
varies even under similar experimental conditions. Differences in intrinsic
phytase
activity of maize/soybean meal-based diets may be responsible for this. The 6-
phytase
used has the potential to improve the utilisation of plant P in duck feeding. A plateau in response was reached above 1500 U/kg.
...
PMID:Phytase effects on the efficiency of utilisation and blood concentrations of phosphorus and calcium in Pekin ducks. 1678 55
1. A total of 2208 broiler chicks were used in two growth experiments (8 treatments and 12 replicate pens in each experiment) to assess the effects of xylanase, amylase, protease and
phytase
in maize-based diets. 2. A positive control diet was formulated containing adequate nutrient concentrations. A negative control diet was formulated to contain approximately 628 kJ/kg, 0.13%, 0.12% and 1 to 2% less metabolisable energy (ME), phosphorus (P),
calcium
(Ca) and amino acids, respectively, than the positive control. In addition, two further negative control diets that contained 167 or 334 kJ/kg more ME, respectively, than negative control 1 were formulated. 3. A further 4 dietary treatments were made by supplementing each of the 4 negative control diets with a combination of xylanase, amylase, protease and
phytase
, resulting in 8 dietary treatments in a 4 by 2 factorial arrangement. 4. The scale of the removal of energy, P, Ca and amino acids from the positive control diet was determined using least square models based on in vivo data for both the xylanase/amylase/protease cocktail and for
phytase
and it was predicted that performance of birds fed on negative control 1 would be returned by supplemental enzymes to that of those fed on the positive control. 5. In both experiments there was a significantly poorer performance in birds fed on the negative control 1 than in those fed on the positive control. The poorer weight gain and feed conversion ratio could be attributed in part to a reduced intake of digestible energy, P, nitrogen (N) and amino acids associated with birds fed on the negative control diet. 6. Supplementation of the negative control diets with the enzyme combination returned performance to that of the positive control in both experiments. 7. These data indicate that exogenous xylanase, amylase, protease and
phytase
can be used successfully in a strategically formulated low nutrient density diet to maintain performance to that of birds fed on a nutritionally adequate diet.
...
PMID:Prediction of ingredient quality and the effect of a combination of xylanase, amylase, protease and phytase in the diets of broiler chicks. 1. Growth performance and digestible nutrient intake. 1690 75
1. In order to investigate the effects of xylanase, amylase, protease and
phytase
in the diets of broiler chickens containing graded concentrations of metabolisable energy (ME), two 42-d experiments were conducted using a total of 2208 broiler chicks (8 treatments with 12 replicate pens in each experiment). 2. Four diets including one positive and three negative control diets were used. Three maize/soybean meal-based negative control (NC) diets were formulated to be identical in available phosphorus (P),
calcium
(Ca) and amino acids but NC1 contained approximately 0.17 MJ/kg less ME than NC2 and approximately 0.34 MJ/kg less ME than NC3. A positive control (PC) was fed for comparison and was formulated to be adequate in all nutrients, providing approximately 0.63 MJ/kg ME, 0.13% available P, 0.12% Ca and 1 to 2% amino acids more than NC1. 3. The reduction in nutrient density between NC1 and PC was determined using ingredient quality models Avichecktrade mark Corn and Phychecktrade mark that can predict the response to exogenous enzymes in maize/soybean meal-based broiler diets. Supplementation of each diet with or without a cocktail of xylanase, amylase, protease and
phytase
gave a total of 8 dietary treatments in a 4 x 2 factorial arrangement. The same treatments and diet designs were used in both experiments but conducted in different locations using different batches of maize, soybean meal and minor ingredients. 4. In both experiments, digestibility was improved by the addition of exogenous enzymes, particularly those for P, Ca and certain amino acids. In addition, the supplementation of the PC with enzymes elicited a positive response indicating that over-the-top addition of xylanase, amylase, protease and
phytase
may offer a nutritionally and economically viable alternative to feed cost reduction. 5. It can be concluded that the digestibility of nutrients by broilers fed on maize/soybean meal-based diets can be improved by the use of a combination of xylanase, amylase, protease and
phytase
.
...
PMID:Prediction of ingredient quality and the effect of a combination of xylanase, amylase, protease and phytase in the diets of broiler chicks. 2. Energy and nutrient utilisation. 1690 76
1. The role of cholecalciferol and phosphorus in the regulation of intestinal mucosa
phytase
was investigated in broiler chicks. 2. A total of 144 7-d-old male broiler chicks were grouped by weight into 6 blocks of 4 cages with 6 broiler chicks per cage. Four maize-soybean meal-based mash diets were randomly assigned to cages within each block. The 4 diets consisted of cholecalciferol at 0 or 75 microg/kg and total phosphorus at 3.6 or 7.0 g/kg in a 2 x 2 factorial arrangement. The birds were given the experimental diets for 12 d under conditions which excluded ultraviolet light. 3. Broiler chicks fed on diets with the higher concentration of cholecalciferol had higher Vmax and Km of the mucosa
phytase
, weight gain, feed intake, feed efficiency and percentage tibia ash, higher ileal digestibility of dry matter, energy, phosphorus (P) and
calcium
(Ca), and increased retention of dry matter, nitrogen, P, Ca and energy. 4. Broiler chicks receiving diets with the higher P concentration showed lower Vmax and Km of the intestinal mucosa
phytase
but greater weight gain, feed intake, feed efficiency and percentage tibia ash, higher ileal digestibility of dry matter, energy, P and nitrogen, and increased retention of dry matter, energy, nitrogen and Ca. 5. In conclusion, both dietary P and cholecalciferol influenced the activity of intestinal mucosa
phytase
.
...
PMID:Dietary cholecalciferol and phosphorus influence intestinal mucosa phytase activity in broiler chicks. 1705 Jan 9
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