Phytate is the primary phosphorus storage molecule of plants and plays a major role in animal nutrition. To enhance phosphate availability and absorption in livestock, and to reduce eutrophication by liquid manure, bacterial phytases are often added to animal feed. The dephosphorylated form of phytate, the polyol myo-inositol (myo-Ins) with multiple functions in eukaryotes, is metabolized by approximately 30% of all bacterial species. Here, we employed a culturomics approach to identify possible metabolic interactions between phytase-producing and myo-Ins degrading bacteria in intestinal samples from pigs. Selective cultivation revealed an unexpectedly high abundance of myo-Ins degrading bacteria, suggesting substantial phytate dephosphorylation in the pig gut. Phytase activity assays performed on gut isolates showed a high degree of variability, suggesting the presence of a diverse set of phytases yet to be characterized. Furthermore, using supernatants of phytase-positive gut strains cultivated in the presence of phytate, we observed cross-feeding of myo-Ins from phytase producers to phytase-negative strains, including the pathogen Salmonella enterica serovar Typhimurium. The data demonstrate that a wide range of commensal bacteria can potentially benefit from phytase activity by utilizing myo-Ins, released through phytate hydrolysis, as a growth substrate. Video Abstract.

Phytic acid in grains chelates essential minerals, thereby reducing the bioavailability of phosphorus and micronutrients in maize-based food and feed. Understanding the temporal expression pattern of the phytase1 gene, which regulates phytase activity, holds immense potential for maize biofortification efforts. The expression of the phytase1 gene and its impact on phytase activity were explored at different grain developmental stages using maize inbreds with contrasting activity. The phytase1 expression pattern was analyzed using quantitative RT-PCR with adh1 as a reference gene. Combined ANOVA revealed significant variation (p < 0.01) due to inbreds (G) and developmental stages (DAP). High phytase genotypes, PMI-Q1 (1302.0 U kg- 1), PMI-PV7 (1345.0 U kg- 1), and PMI-PV8 (1413.3 U kg- 1) showed higher expression of the phytase1 gene transcript levels of 0.114, 0.109, and 0.104, respectively. PMI-PV2 (586.4 U kg- 1), PMI-PV4 (688.3 U kg- 1), and PMI-PV5 (650.8 U kg- 1) with the lower phytase activity had lower expression of phytase1 transcript levels of 0.040, 0.031, and 0.036, respectively. Furthermore, the correlation between phytase activity and relative expression pattern at different developmental stages was positive (p < 0.01; r = 0.79, 0.86, and 0.89 at 15, 30, and 45 DAP, respectively). Notably highest phytase activity was found at 15 DAP (1127.7 U kg- 1) and declined progressively towards 45 DAP (895.4 U kg- 1) across genotypes, with a corresponding reduction in phytase1 gene expression. Validating the high phytase genotypes through gene expression profiling offers promising donors for maize molecular breeding to transfer high phytase activity into elite genotypes.

The present study investigates the techno-functional and biosafety potential of Meyerozyma guilliermondii YB1 (OQ832654) as a novel starter culture for functional foods. M. guilliermondii YB1 exhibited xylanase and phytase activity, with an activity index (AI) of 0.66 and 0.21, respectively. Antimicrobial assays demonstrated inhibition against Escherichia coli MTCC 3222, Salmonella typhimurium MTCC 3224, and Aspergillus sp. CTS1, confirming its potential in food preservation. Furthermore, the yeast efficiently fermented a broad range of carbohydrates required for food fermentations. Auto-aggregation increased from 25% at 2h to 96.04% at 72h, while hydrophobicity ranged from 38.54% to 66.16%, indicating strong gut adhesion properties. Growth at 37°C followed a normal sigmoidal curve, with optimal proliferation up to 48h. Bile salt tolerance (0.3%) and acid resistance (pH 2.5-3.5) further confirmed its survival under gastrointestinal conditions. The non-pathogenicity of M. guilliermondii YB1 was confirmed through antifungal susceptibility testing, absence of gelatinase, DNase activity, and a negative Congo red binding test, thereby supporting its use as a reliable functional food starter. Collectively, these attributes establish M. guilliermondii YB1 as a promising candidate for functional food applications, offering improved digestibility, food safety, and health benefits.

Pulses are recognized as sustainable foods due to their high nutritional density, low environmental footprint, and versatility as plant-based ingredients. Fermentation has emerged as a powerful bioprocessing tool to further enhance nutritional, sensory, techno-functional, and health-promoting properties of pulses. This review summarizes recent advances in the fermentation of commonly consumed pulses using lactic acid bacteria, yeasts, molds, and co-fermentation microorganism consortia, focusing on the biochemical mechanisms underlying changes in their nutritional and bioactive potential. Microbial metabolism (i.e., α-galactosidase and phytase activity) reduces antinutritional factors, such as raffinose family oligosaccharides and phytic acid, while promoting the release of bound nutrients and bioactive compounds as phenolics, increasing their bioaccessibility and bioactivity. Microbial amylases change the carbohydrate profile by decreasing simple sugars, modifying starch digestibility, and favoring resistant starch production. Microbial lipases remodel lipids, improving the fatty-acid distribution and nutritional value. Protein hydrolysis by microbial proteases enhances digestibility and generates bioactive peptides with antioxidant and antihypertensive properties, among others. Co-fermentation systems offer additional opportunities to tailor metabolic outcomes, facilitating positive symbiotic interactions between microorganisms. Overall, fermentation represents a key technology to unlock the full potential of pulses as next-generation ingredients, supporting the development of nutritious, functional, and sustainable foods for future food systems.

Abstract Intensified human‐derived nitrogen (N) loading may induce extensive phosphorus (P) uptake limitations in temperate forests. It remains unclear how plants will acclimate to such progressively deprived P environments under N input, especially in terms of adjustments in root P‐acquisition strategies. Here, we show, conducting N input experiments in two temperate forests (natural and secondary forest), that low, medium and high N inputs reduced plant‐available soil P concentrations by 9.3%, 15.7% and 16.3% in natural forests, and by 29.0%, 31.0% and 28.2% in secondary forests, respectively. This suggested that the natural forest had a stronger buffering capacity for N inputs, consequently resulting in a relatively lower impact on soil P availability. Importantly, continuous N input stepwise altered the P‐acquisition strategy of temperate forest plant roots. This transition moved from an initial dependence on mycorrhizal symbiosis for soil P acquisition to the mobilization of soil inorganic P by root‐released carboxylates, and ultimately to the inorganic P acquisition through the facilitation of the mineralization of organic P by rhizosheath phosphatases and by the enhancement of the ability of roots to scavenge the soil matrix. Simultaneously, plant rhizosheath phosphomonoesterase, phosphodiesterase and phytase activities responded divergently to declined soil P availability, suggesting that increased N inputs altered plant mineralization preference and strategy for soil organic P with different chemical forms. Synthesis . These shifts in root P‐acquisition strategy reveal the adaptive strategies adopted by plants when soil P becomes increasingly limiting, also reflecting the profound effects of N inputs on plant allocation of below‐ground carbon (C) resources. Together, this study elucidated that N inputs remodelled C‐P coupling in temperate forests by altering root plasticity and C‐investment strategies.

This study focused on phytase overproduction in recombinant E. coli BL21(DE3)/pET-appA expressing E. coli phytase(APPA). A modified mineral salt medium was investigated for the strain growth and phytase production in shake-flask, which included 30mM NH4OH and 17g L-1 KH2PO4 as sole nitrogen(N) and phosphorous(P) sources, respectively. After that, fed-batch cultivation process, especially induction strategy feeding lactose intermittently was optimized in 30L bioreactor by Taguchi orthogonal experiments (L18(21 × 36)) at an induction cell density of OD600 25, followed by research on effect of induction cell densities. The optimized fed-batch cultivation process parameters included glucose starvation time of 15min just before induction, induction cell density of OD600 45, induction temperature of 25°C, predetermined specific growth rate of 0.04h-1, DO level of 15%, lactose concentration of 60mM, lactose feed times of 6 times, and pH of 7.2-7.6. In the optimized condition, the highest soluble phytase activity of 2 152UmL-1 ever reported was obtained at 33.0h, indicating the enhancements of 31.6-fold and 3.7-fold compared to batch cultivation process in shake flask and pre-optimized fed-batch cultivation process in the bioreactor, respectively. We propose that the defined medium, the induction strategy and fed-batch process parameters could be applied to overproduce soluble proteins in E. coli.

Evaluating phytase activity and amino acid density as suitable on-farm nutrient segregation markers: Effects on broiler performance, processing yields, and bone mineralization

The mechanism of microbial-mediated mineralization of organic phosphorus (P) under nitrogen (N) addition in farmland soil is still unclear. To determine the effects of N addition on the composition, structure, and P transformation function of microbial community and soil P fractions in croplands, we conducted a field experiment on the Central Gansu Loess Plateau in 2017. The current study analyzed a subset of 12 plots from the 48-plot factorial experiment, comprising four levels of N addition in the absence of P fertilization. The treatment included control (0 kg N ha−1 year−1, N0), low N (75 kg N ha−1 year−1, N75), medium N (115 kg N ha−1 year−1, N115), and high N (190 kg N ha−1 year−1, N190). We determined soil P fractions and microbial properties in the 0–20 cm depth from 2019 to 2023. We found that N fertilization significantly enhanced the mineralization of soil organic P, primarily by altering microbial community structure and increasing the abundance of key taxa (e.g., RB41 and Filobasidium), which in turn boosted the activities of alkaline phosphatase (ALP) and phytase (PHY). The most pronounced stimulations in microbial biomass carbon (MBC) and ALP activity were observed under the N115 treatment. Concurrently, N addition led to substantial reductions in labile inorganic and organic P pools; for instance, the content of Ca2-P decreased most markedly under N190, by 42.82% in 2023, while labile organic P forms (LOP, MLOP, MROP) also declined significantly. Structural Equation Modeling (SEM) confirmed that N addition influenced P availability through direct pathways and indirect pathways mediated by shifts in microbial community structure, ALP, and PHY. In conclusion, our study has identified the N115 treatment (115 kg N ha−1 year−1) as the optimal level for promoting microbial-mediated organic P mineralization. To maintain soil productivity in the rain-fed agricultural systems of the Loess Plateau, we recommend applying a moderate amount of N fertilizer at this optimal rate, along with strategic P supplementation. This approach can effectively mitigate soil P deficiency and enhance the availability of P.

Phosphorus unavailability is a major constraint limiting crop productivity, necessitating sustainable alternatives to chemical fertilizers. In the present study, phosphate-solubilizing bacteria (PSB) were isolated from the rhizosphere soils of legume crops collected across Nalgonda, Mahabubnagar, and Rangareddy districts, Telangana, India. Among the ten efficient PSB isolates selected based on halo zone formation on Pikovskaya’s agar (7.1–11.4 mm), isolate PSBP-2 exhibited the highest phosphate solubilization efficiency with a halo zone diameter of 11.4 mm. Quantitative estimation further confirmed its superior performance, releasing 58.7 ± 0.20 µg/mL of soluble phosphate in Pikovskaya’s broth. PSBP-2 also demonstrated strong plant growth–promoting traits, including the highest indole-3-acetic acid (IAA) production (48.0 ± 2.0 µg/mL), notable phytase activity with a hydrolysis zone of 12 mm, maximum biofilm formation (OD₆₀₀ = 0.78 ± 0.05), and the highest ammonia production (0.48 ± 0.03 OD₄₅₀). Morphological and biochemical characterization revealed that PSBP-2 is a Gram-positive, rod-shaped, capsulated, spore-forming bacterium with positive methyl red, citrate utilization, starch hydrolysis, and carbohydrate fermentation reactions. Molecular identification based on 16S rRNA gene sequencing confirmed the isolate as Bacillus altitudinis strain PUPB PSBP-2 (GenBank accession number: PX239710), which clustered within the Bacillus altitudinis clade in phylogenetic analysis. The integration of high phosphate solubilization, auxin production, organic phosphorus mineralization, and rhizosphere colonization traits establishes Bacillus altitudinis PUPB PSBP-2 as a promising multifunctional plant growth–promoting rhizobacterium with potential application as a biofertilizer for sustainable legume cultivation.

Introduction: Phytase enzyme catalyzes the hydrolysis of phytate, an anti-nutrient compound present in cereals and grains, to release orthophosphate and myo-inositol hexakisphosphate with lower degrees of phosphorylation, with metal ions, proteins, and starch chelated to phytate naturally. The study aimed to screen potential phytase-producing bacterial isolates and characterize the extracellular phytase of the bacterial isolate with the best phytase activity. Methods: A promising isolate (R5-C2-C4) out of thirty tested bacterial strains, which showed the best hydrolysis efficiency on Phytase Selective Medium (PSM) plates, was selected to investigate phytase production in Liquid Phytase Selective Medium (LPSM) under constant conditions of 37°C and pH 7.0 during a 72-hour incubation period, with measurements taken at 24-hour intervals using phytase production activity assay. Results: The local isolate Bacillus subtilis (C4) was found to produce significantly the highest phytase activity of 0.818 Unit/ml out of the tested isolates during 72 h of incubation at 37°C with the pH of 7.0 as a characterization of crude phytase. Discussion: Enzyme activity and stability under varying pH and temperature conditions are always a significant challenge during food and feed processing. Most studies indicate that bacterial phytase and especially Bacillus sp. phytase had a pH optimum of (6.5-7.5), and optimum temperature of (35-60)°C, where the phytase parameters of this study isolate, Bacillus subtilis found to be in the same range. Conclusion: The local isolated Bacillus subtilis produces its significant amount of phytase with ideal production parameters, which would considerably make it useful for applications in feed and food.

The study on antagonist effects of cocktail enzyme activity on antagonist effects of cocktail enzyme activity analysis of mixed enzyme revealed stable protease activity across time, while cellulase, xylanase, and phytase activities significantly declined after prolonged mixing with protease (p&lt;0.05). Nutritional composition of R-DDGS improved with enzymatic treatment, exhibiting higher crude protein (up to 56.6%) and enhanced protein digestibility, alongside reduced fiber and phytic acid levels. The study in shrimp involved juvenile white shrimp (Litopenaeus vannamei) cultured under control condition over a 42-day period. The results showed that shrimp fed enzyme-treated R-DDGS diets (T3-protease, T4-Protease+NSP, T5-Protease+NSP+phytase) demonstrated significant improvements in growth performance compared to shrimp fed untreated R-DDGS (T2) and in the same range as Control-soybean meal diet (T1). Enzyme treated diets also modulated immune responses, with a reduction in total hemocyte count (THC) and stable levels of other immune markers. Additionally, R-DDGS diets enhanced protein digestibility, reflected in higher reducing sugar levels and carbohydrate breakdown (p&lt;0.05). The shrimp coloration (a and b values) did not differ significantly, enzyme-treated diets supported slight improvements in pigmentation, enhancing market value (p&lt;0.05). These findings underscore the potential of enzyme-treated R-DDGS as a sustainable alternative feed ingredient for aquaculture, offering improved nutrient utilization, growth performance, and immune modulation.

Isolation and functional characterization of phytase extracted from Klebsiella pneumoniae for enhanced growth of plants: A study of gene expression and in silico prediction.

ABSTRACT Phytic acid is the main storage of phosphate in grains of staple crops. As phytic acid is hardly digestible for non-ruminants microbial phytases are used to supplement animal feed to enhance phosphate digestibility. A fungal phytase gene was introduced into barley with the aim of enhancing phosphate digestibility. Transgenic homozygous barley over-expressing fungal phytase phyA showed a 3.3fold increase in mature grain phytase activity. Field trials at two locations in the Czech Republic were conducted in a five-year experiment to test transgene stability and activity under field conditions. Increased phytase activity gradually decreased over the generations showing the most significant drop in the initial years of field trials. Molecular analysis revealed methylation in the coding sequence of the phyA transgene, suggesting transcription gene silencing. On the other hand, herbicide resistance used for selection of transgenic plants was functional over all generations. The feasibility of crossing the transgene into the feeding cultivar Azit was demonstrated with subsequent stabilization of hybrid progeny through androgenesis. Our results indicate that the Azit genetic background tended to reduce phytase activity in mature grains of hybrids. Grain-specific over-expression of fungal phytase driven by an amylase promoter improved phosphate levels during germination. Unfortunately, a malting experiment revealed that phytase over-expression did not significantly improve malting parameters. In fact, the higher nitrogen content in unmalted grain negatively affected the quality of the malt produced from them.

Phytate is an anti-nutrient factor that chelates micronutrients, thereby reducing their bioavailability and impairing nutrient absorption in humans and animals. This study aimed to isolate and assess potential probiotic yeast strains with phytase capability from Thai traditional fermentation starters. Three yeast isolates revealed antagonistic activity against pathogenic bacteria in preliminary probiotic screening and demonstrated phytate-degrading capabilities through phytase activity. Among the selected yeast strains, isolate NS104-STR showed the highest extracellular phytase activities (0.142 ± 0.001 U/mL and 0.126 ± 0.001 U/mg protein). Phylogenetic analysis based on 18s rDNA and/or TSI gene regions identified this strain as closely related to Pichia kudriavzevii. Pichia kudriavzevii NS104-STR displayed several desirable probiotic attributes. This strain exhibited broad-spectrum bacteriostatic activity and tolerance to acidic conditions (≥ 106CFU/mL at pH 2.0 and ≥ 108CFU/mL at pH 3.0 for 3h of exposure) as well as survival in 0.3-0.6% bile salts after 24h of exposure (> 100% survival rate) (p ≤ 0.05). Furthermore, it also displayed high cell surface hydrophobicity (65.65 ± 0.35%), auto-aggregation capacity (61.08 ± 0.25%), and strong adhesion to Caco-2 epithelial cells (66.39 ± 0.69%). Pichia kudriavzevii NS104-STR was capable of co-aggregating with pathogens and significantly inhibited their adhesion to Caco-2 cells in competition exclusion assays (> 50% of inhibition rate), especially E. coli ATCC 25922 (67.68 ± 0.18% of inhibition rate) (p ≤ 0.05). Importantly, P. kudriavzevii NS104-STR was non-hemolytic and susceptible to various antibiotics and antimycotics. These results suggest that Pichia kudriavzevii NS104-STR may serve as a promising potential phytase-producing probiotic yeast, with valuable applications in enhancing the nutritional quality of food and feed products.

BackgroundRecombinant phytase production has recently gained increased recognition in phosphate recycling from phytate contained in plant-based side and waste streams. Until now, new phytase variants are evaluated at the end of the expression by standard offline screening procedures, where promising candidates with high activities and protein titers are identified. However, for large mutant libraries, this implies extensive laboratory work for a first screening of hundreds of clones. In this study, for the first time, two synergistic concepts for the primary screening of phytases were investigated.ResultsThe aim was to predict high recombinant protein producer strains as well as high volumetric activity phytase variants, based on the development of the respiratory activity over time of the host cell, in this case, Komagataella phaffii (Pichia pastoris). In a first step, the metabolic burden was investigated by cultivating a clone library in YPD medium in a µTOM device. It was found that strains expressing medium or high protein concentrations show clear characteristics of an elevated level of metabolic burden during constitutive expression. However, a high protein concentration does not imply a high enzymatic activity. Therefore, in a second approach, the screening was adapted to screen for phytase variants with high volumetric activity. To do so, a modified Syn6 MES medium was developed, where phytic acid was used as the only phosphate source. Thereby, only clones secreting active phytase and generating free phosphate were able to grow, which was monitored via the oxygen transfer rate. A correlation between the offline measured volumetric phytase activity and µmax was found. The clones were then ranked according to their online and offline performance and the results matched in 83% of the cases.ConclusionOnline monitoring of the oxygen transfer rates in 96-well plates allowed for the evaluation of the total protein concentration and the volumetric phytase activity already during the expression. Using these results, also the specific activity can be calculated. In the future, primary screening experiments of large enzyme mutant libraries can be conducted without offline activity assays, to identify promising candidates.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12934-025-02806-w.

Phytate (salts of myo-inositol-1,2,3,4,5,6-hexakisphosphate) constitutes a large portion of the organic phosphorus in most soils, but its strong interactions with soil minerals and organic matter limit its availability to plants. Phytate can be used by plants only after it is desorbed from the soil matrix, with the inorganic P being released by phytases via cleavage of its phosphomonoester bonds. While plant phytases function primarily in its internal phytate remobilization, the role of microbial phytases in facilitating phytate-P utilization by plants remains poorly understood. This review focuses on phytase-producing plants and microbes and their uses in improving crop P acquisition from soil phytate. We discuss the behaviors of phytate and phytase in soils, especially their complex interactions with metal oxides, silicate minerals, and organic matter. Strategies to optimize soil phytase activity, including enzyme immobilization, site-directed mutagenesis, and rational protein design are also explored. Besides, we examine the mechanisms and hydrolysis pathways involved in phytase-mediated phytate hydrolysis, identifying situations where phytate utilization is limited by phytate solubility or phytase activity from an evolutionary perspective based on cultivation conditions and plant characteristics. Finally, we summarize strategies to increase plant utilization of soil phytate, including (1) amending soil with phytase-producing microbes, (2) expressing phytase gene in plant roots, (3) coupling phytase and organic acid exudation from plant roots, (4) intercropping phytase-producing plants with organic acid-secreting plants, and (5) incorporating phytase into plants with great organic acid production as cover crops. As these strategies are effective only in specific environments, future studies should focus on: (1) developing novel phytases with high activity and resistance to soil deactivation, (2) cultivating plants that effectively secrete phytase and mobilize soil phytate, and (3) engineering microbial consortia with stable and efficient phytate hydrolysis capabilities. Besides, integrated catalyst systems combining biological and chemical approaches also offer promising solutions for soil phytate hydrolysis. These strategies will exploit stable soil organic P by crop plants while simultaneously decreasing agricultural dependence on P fertilizer and reducing P loss to the environment.

Application of phytase (myo-inositol hexakisphosphate phosphohydrolase) to catalyze the release of phosphate from phytates contained on grain-based feed has been used widely. This study was carried out to isolate, identify, screen and produce yeast phytase from cereals using submerged fermentation. Two hundred and twenty seven (227) yeast isolates were obtained from maize, sorghum and millet and identified based on various characteristics such as colony morphology, microscopy, biochemical tests, sugar fermentation tests and molecular analysis. The isolates were then screened for phytase production by growing them on Phytase Screening Medium (PSM) and observing the formation of a clear zone around their colonies, indicating their ability to degrade phytate. It was found that yeast species such as Pichia membranefaciens, Meyerozyma guilliermondii SWS81, Candida krusei, M. guilliermondii M122, Pichia fermentans, M. guilliermondii WM226 and Schwanniomyces occidentalis, were capable of phytate degradation. M. guilliermondii M122, M. guilliermondii SWS81, and M. guilliermondii WM226 with higher solubilizing indices (4.52 mm, 3.64 mm and 5.14 mm respectively) were selected for production and assay. The results showed that crude enzymes from these yeast strains had phytase activity ranging from 44.70 U/mL to 97.70 U/mL, making them potential supplements for animal feeds to improve nutritional status and combat environmental phosphorus pollution.

Wheat bran (WB), but also hulls from rice, oat, sunflower and soybean, wood chips, and industrial fiber byproducts are among the main sources of insoluble fiber in poultry nutrition. Insoluble fiber (IF) in poultry is more than a diet-diluent because of it improves performance, digestive tract ecology, and health in poultry. Feeding of 2.5-3.5% of IF could improve feed efficiency and nutrient digestibility, whereas soluble dietary fiber (SDF) causes increased viscosity, intestinal transit time, and decreased feed intake, digestibility, and growth rate. The nutritional advantages of WB include the high fiber (48-53%), protein (9.6-18.6%), vitamin B, betaine, and minerals, as well as the improvement of health status and production. Microbial fermentation is utilized to enhance the nutritional properties of wheat bran fiber by incorporating fungi, bacteria, and yeast. Wheat bran, rich in dietary fiber microorganisms like Aspergillus, Saccharomyces, Lactobacillus, and Bacillus. Used in fermentation process under controlled conditions (temperature, pH, oxygen, and moisture levels) promote microbial growth, improves nutrient content, digestibility, and gastrointestinal health, making wheat bran a valuable feed ingredient for poultry nutrition. The main challenge of WB feeding is due to its high fiber content, anti-nutritional factors affecting the digestion and absorption of nutrients, intestinal viscosity, and microbiota. Diets diluted with WB affect the amount of endogenous and exogenous enzymes, intestinal length and relative weight of the gizzard. Intrinsic phytase is one of the less discussed advantages of WB in monogastric nutrition; it increases the bioavailability of phosphorus and several other nutrients and reduces the need to add exogenous phytase and phosphate sources. Endogenous WB phytase was completely released at pH 3-5 by microbial phytase from the aleurone layer. Phytase activity depends on the type of wheat and phytase matrix. The addition of appropriate levels of exogenous enzymes is effective in regulating the gene expression of digestive enzymes and improves the release of trace elements and bone matrix. In this review, based on the available literature, we concluded that the benefits of using WB were much greater than other fiber sources, but more research is needed to compare this valuable fiber source in terms of gut ecology, gene expression, digestibility, behavior, and its interactions with different fat sources.

Abstract Calcium (Ca) and phosphorus (P), two main elements, have vital physiological and metabolic roles in animal bodies. Accurate comprehension of the interaction of these two elements and their value in various resources helps to obtain their optimal formulation in poultry diets. Hence, in previous studies, the hormonal axes controlling Ca and P homeostasis have been primarily investigated. However, to estimate Ca and P requirements in modern broiler chickens, in addition to growth performance, other parameters such as Ca and P digestibility, bone strength, and excretion into the environment should also be considered. Since a large amount of P in poultry feed ingredients is bound to phytate, phytases are added to poultry diets to release the P from phytate. However, many nutritionists need clarification on what dose of dietary phytase is required to release the maximum phytate P and how phytase activity will be optimized. Therefore, the present review study has attempted to explore the factors that affect the digestibility of different sources of Ca and P. In addition, the effect of excess dietary Ca on phytase activity and studies related to superdosing of phytase in broilers are provided. Finally, the values of phytate P in standard poultry feed ingredients and the latest update of the studies on determining Ca and P requirements are summarized.

Unveiling the functionality of phytase activity in maize for enhanced bioavailability of minerals: a new avenue for nutritional security