Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
1,795 result(s) for "phytases"
Sort by:
Effect of Germination on the Nutritional Properties, Phytic Acid Content, and Phytase Activity of Quinoa (Chenopodium quinoa Willd)
The aim of this study is to evaluate the effect of desaponification, soaking, germination, and refrigerated storage on the phytase activity, phytic acid content, and nutritional properties of three varieties of quinoa: white, red, and black. Desaponification and soaking reduced the number of minerals and the nutritional content. Germination of the seeds was carried out in the desaponified samples. The nutritional values, phytase activity, and phytic acid content of quinoa were measured after 6 h of soaking and then at 4 and 7 days during germination plus 7 days of refrigerated storage (4 °C). Germination increased the fibre and protein content as well as the iron, zinc, and calcium content. Germination significantly increased the phytase activity in all varieties and decreased the phytic acid content. The phytic acid content decreased during germination from 32 to 74%. Refrigerated storage had no significant effect on most of the factors studied. Germination boosts nutritional content and phytase activity while decreasing phytic acid content. Germination can be a simple method to reduce phytic acid in quinoa and may also improve the nutritional quality of this pseudocereal with the potential for use in functional foods and vegetarian diets.
Ultrasound-assisted Modification of Enzymatic and Antioxidant Activities, Functional and Rheological Properties of Oat and Barley Bran
Cereal bran possesses enzymes and antinutrients which should be reduced for their usability as a food ingredient high in dietary fiber, minerals, and antioxidants. This study investigated the influence of high-intensity ultrasound on enzymatic and antioxidant activities, phytic acid content (PA), and functional and rheological properties of oat and barley bran. Ultrasonication was performed at three specific energies (87 kJ/kg, 217.5 kJ/kg, and 348 kJ/kg), without or with pulsation (5 s emission, 10 s pause). Bran was assessed for β-glucanase, phytase and antioxidant activities, PA and total phenolic content, hydration, and rheological properties. β-glucanase from oat bran was inactivated up to 82% and from barley bran up to 55%, depending on the ultrasound-specific energy and pulsation. PA and antioxidant activities were higher in native oat bran (PA 17.35 mg/g d.w., FRAP 6.96 µmol TE/g d.w., 3.30 µmol FAE/g d.w.) compared to barley bran (PA 11.53 mg/g d.w., FRAP 2.27 µmol TE/g d.w., 5.30 µmol FAE/g d.w.). In both bran types, phytase activity increased (40–44%) after treatments at 87 kJ/kg, and on average, PA was reduced by 17% in oat bran and by 39% in barley bran. Depending on the energy and pulsation, bran ultrasonication reduced total phenolic content (27–55%), antioxidant activity (by 28–48%), complex viscosity (62–71%), and maximum stress tolerance (46–68%) while increased water swelling (42–48%) and retention capacity (44–59%). Hence, high-intensity ultrasound is a useful technique in reducing antinutrients while altering the enzymatic activity and functional properties of the bran. These results could help the wider application of bran in food production.
Cross-linked phytase aggregates for improved phytate degradation at low pH in animal feed
Phytases are widely used food and feed enzymes to improve phosphate availability and reduce anti-nutritional factors. Despite the benefits, enzyme usage is restricted by the harsh conditions in a gastrointestinal tract (pH 2–6) and feed pelleting conditions at high temperatures (60–90 °C). The commercially available phytase Quantum® Blue has been immobilized as CLEAs using glutardialdehyde and soy protein resulting in a residual activity of 33%. The influence of the precipitating agent, precipitant concentration, cross-linker concentration and cross-linking time, sodium borohydride as well as the proteic feeders gluten, soy protein and bovine serum albumin (BSA) has been optimized. The best conditions were 90% (v/v) ethyl lactate as precipitating reagent, 100 mM glutardialdehyde and a soy protein concentration of 227 mg/L with a cross-linking time of 1 h. The intrinsically stable phytase remained its high thermal stability and temperature optimum. The phytase-CLEA achieved a 425% increase of residual activity under harsh acidic conditions between pH 2.2 and 3.5 compared to the free enzyme. The free and immobilized phytase were deployed in an in vitro assay simulating the acidic conditions in the gizzard of poultry at pH 2. The hydrolysis of phytate was monitored using a novel high-performance thin-layer chromatography (HPTLC) analysis and DAD scanner to study the InsPx fingerprint. All lower inositol phosphate pools (InsP1–InsP6) and free phosphate were separated and analyzed. The phytase-CLEA efficiently released 80% of the total phosphate within 180 min, whereas the free enzyme only released 6% in the same time under the same conditions.
Comparison of Phosphorus and Phytase Activity Distribution in Wheat, Rye, Barley and Oats and Their Impact on a Potential Phytate Separation
When facing today’s scarcity of mineral phosphorus (P) resources and the environmental issues following enhanced P losses especially from agriculture, new solutions need to be implemented. In this framework, the potential for a mechanical separation of a P rich grain fraction from wheat, rye, barley and oats is investigated in order to provide animal feed with reduced organic P content. Thus, P accumulation in manure and soils should be prevented. Also, the subsequent utilization of the separated organic P, which occurs in the form of inositol P, for a sustainable P management via activation of intrinsic enzymes is evaluated. It was shown that in grain layers at 7.0, 5.5, 6.4 and 2.5% cross section of wheat, rye, barley and oats, respectively, maximum inositol P occurs with 1.6, 0.8, 1.4 and 1.2 g/100 g. Phytase activity is also highest in the outer layers of the grains with maxima of 9300, 12,000, 8400 and 2400 U/kg, respectively. A removal of the specific layers where inositol P is accumulated could possibly achieve a 24, 31, 60 and 27% organic P reduction for wheat, rye, barley and oats with 7, 14, 25 or 7% grain elimination. A debranning, eliminating all the outer grain layers to a certain extent, in contrast, leads to significantly higher mass losses. Within the P enriched layer determined from inositol P distribution, phytase activity is calculated to be around 285, 831, 777 and 42 U/kg for wheat, rye, barley and oats, respectively.
Genome-Scale Characterization of Fungal Phytases and a Comparative Study Between Beta-Propeller Phytases and Histidine Acid Phosphatases
This work intended to prospect new phytase-producing organisms. In silico genomic analyses allowed the selection of twelve potential phytase-producing fungi. Based on gene sequence, it was possible to identify four well-defined groups of phytate-degrading enzymes: esterase-like, β-propeller phytases (βPP), phosphoglycerate mutase-like, and phytases of the histidine acid phosphatases (HAP) family. Analysis of the predicted genes encoding phytases belonging to the HAP family and βPP phytases and in silico characterization of these enzymes indicated divergence among the catalytic activities. Predicted fungal βPP phytases exhibited higher molecular mass (around 77 kDa) probably due to the epidermal growth factor-like domain. Twelve sequences of phytases contained signal peptides, of which seven were classified as HAP and five as βPP phytases, while ten sequences were predicted as phytases secreted by non-classical pathways. These fungi were grown in liquid or semi-solid medium, and the fungal enzymatic extracts were evaluated for their ability to hydrolyze sodium phytate at 50 °C and pH ranging from 2.0 to 9.0. Seven fungi were identified as phytase producers based on phosphate release under enzyme assay conditions. Results obtained from in silico analyses combining experimental enzymatic activities suggest that some selected fungi could secrete βPP phytases and HAP phytases.
Interactions between cover crops and soil microorganisms increase phosphorus availability in conservation agriculture
Aims An essential task of agricultural systems is to improve internal phosphorus (P) recycling. Cover crops and tillage reduction can increase sustainability, but it is not known whether stimulation of the soil microbial community can increase the availability of soil organic P pools. Methods In a field experiment in southwest Germany, the effects of a winter cover crop mixture (vs. bare fallow) and no-till (vs. non-inversion tillage) on microbial P-cycling were assessed with soybean as the main crop. Microbial biomass, phospholipid fatty acids (PLFAs), P cycling enzymes, and carbon-substrate use capacity were linked for the first time with the lability of organic P pools measured by enzyme addition assays (using phosphodiesterase, non-phytase-phosphomonoesterase and fungal phytase). Results Microbial phosphorus, phosphatase, and fatty acids increased under cover crops, indicating an enhanced potential for organic P cycling. Enzyme-stable organic P shifted towards enzyme-labile organic P pools. Effects of no-till were weaker, and a synergy with cover crops was not evident. Conclusions In this experiment, cover crops were able to increase the microbially mediated internal P cycling in a non-P-limited, temperate agroecosystems.
Phytases and the Prospects for Their Application (Review)
Phytases from plants and microorganisms release phospates from poorly soluble phytates, making the phospates more accessible. In this review, some features and biochemical properties of phytases, as well as the areas and prospects for their use, are under discussion. The introduction of phytases into the fodder for food-producing animals increases the product yield without any additional expenses for mineral phosphates. The presense of phytases in the soils reduces the risk of water eutrophication.
Low digestibility of phytate phosphorus, their impacts on the environment, and phytase opportunity in the poultry industry
Phosphorus is an essential macro-mineral nutrient for poultry, needed for the body growth, development of bones, genomic function, good quality flesh, and eggs production. The imbalance of organic phosphorus sources in the diet mostly affect the phosphorus digestibility, reduces the poultry performance and health, and increases the environmental pollution burden. A study was reviewed to estimate the low phytate phosphorus digestibility of ingredients in poultry diet and their impacts on environmental ecosystem and opportunity of phytase supplementation. Plant ingredients mostly used in poultry diets are rich in phytate phosphorus. The phytate phosphorus digestibility and utilization is low in the gut of birds which leads to decrease other nutrients digestibility and increase excessive excretion of phosphorus with additional nutrients in the manure. When that manure applied to the lands containing excessive residual phosphorus and additional nutrients which pollute soil, groundwater disturbed the entire ecosystem. This issue is developed by poultry due to lack of digestive enzyme phytase which promotes the phytate phosphorus during digestion and reduces the excessive losses of phosphorus in excreta. To overcome this matter, the addition of mostly exogenous phospho-hydrolytic phytase enzymes in the diet, i.e. Escherichia coli, Peniophora lycii , Aspergillus niger, and Ficum , are the possible ways to increase the digestibility and utilization of phytate phosphorus and promote the stepwise release of phosphorus from phytate and significantly decrease phosphorus excretion. The aim of this review is to highlight the role of phytase supplementation in the poultry feeding, improvement of phytate phosphorus digestibility with performance, and reduction of phosphorus pollution from the environment.
Plant Growth Promotion at Low Temperature by Phosphate-Solubilizing Pseudomonas Spp. Isolated from High-Altitude Himalayan Soil
Scarcity of arable land, limited soil nutrient availability, and low-temperature conditions in the Himalayan regions need to be smartly managed using sustainable approaches for better crop yields. Microorganisms, able to efficiently solubilize phosphate at low temperatures, provide an opportunity to promote plant growth in an ecofriendly way. In this study, we have investigated the ability of psychrotolerant Pseudomonas spp., isolated from high altitudes of Indian Himalaya to solubilize P at low temperature. Quantitative estimation of phosphate solubilization and production of relevant enzymes at two different temperatures (15 and 25 °C) was performed for 4 out of 11 selected isolates, namely, GBPI_506 (Pseudomonas sp.), GBPI_508 (Pseudomonas palleroniana), GBPI_Hb61 (Pseudomonas proteolytica), and GBPI_CDB143 (Pseudomonas azotoformans). Among all, isolate GBPI_CDB143 showed highest efficiency to solubilize tri-calcium phosphate (110.50 ± 3.44 μg/mL) at 25 °C after 6 days while the culture supernatants of isolate GBPI_506 displayed the highest phytase activity (15.91 ± 0.35 U/mL) at 15 °C and alkaline phosphatase (3.09 ± 0.07 U/mL) at 25 °C in 6 and 9 days, respectively. Out of five different organic acids quantified, oxalic acid and malic acid were produced in maximum quantity by all four isolates. With the exception of GBPI_508, inoculation of bacteria promoted overall growth (rosette diameter, leaf area, and biomass) of Arabidopsis thaliana plants as compared to uninoculated control plants in growth chamber conditions. The plant growth promotion by each bacterial isolate was further validated by monitoring root colonization in the inoculated plants. These bacterial isolates with low-temperature phosphate solubilization potential along with phosphatases and phytase activity at low temperature could be harnessed for sustainable crop production in P-deficient agricultural soils under mountain ecosystems.
Bioprocess for Hyperactive Thermotolerant Aspergillus fumigatus Phytase and its Application in Dephytinization of Wheat Flour
In the present study, statistically optimized production of thermotolerant Aspergillus fumigatus phytase was carried out in batch fermentation (1-L). An enhancement in phytase production was noted up to 3.3-folds as compared to unoptimized and using One Variable at a Time strategy. Phytase was purified up to 26-folds with a single band of ~ 62 kDa. The optimum activity of purified phytase was recorded at pH 5.5 and 65 °C. The kinetic parameters, Km and Vmax, were observed to be, 0.75 mM, and 345 µmol/min/mg-protein,respectively. The activity was constrained by silver and mercuric ions and slightly increased by calcium ions. The phytase showed high dephytinization up to 78.7% of wheat flour (10 g) at a small reaction volume (30 mL). On up-scaling to 3-L reaction, a slight decrease in dephytinization to 72.5% was recorded. This is the first report where hyperactive purified phytase from thermotolerant A. fumigatus has been demonstrated to degrade wheat flour-based phytic acid up to a 3-L scale at the bioreactor level. This finding can be explored at a commercial scale for multi-dimensional future biotechnological applications.