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.

Phytate and Arsenic Enhance Each Other's Uptake in As-hyperaccumulator Pteris vittata: Root Exudation of Phytate and Phytase, and Plant Uptake of Phytate-P.

Phytate as a root exudate is rare in plants as it mainly serves as a P storage in the seeds; however, As-hyperaccumulator Pteris vittata effectively secretes phytate and utilizes phytate-P, especially under As exposure. This study investigated the effects of As on its phytate and phytase exudation and the impacts of As and/or phytate on each other's uptake in P. vittata through two hydroponic experiments. Under 10-100 µM arsenate (AsV), the exudation of phytate and phytase by P. vittata was increased by 50-72% to 20.4-23.4 µmol h-1 g-1 and by 28-104% to 18.6-29.5 nmol h-1 plant-1, but they were undetected in non-hyperaccumulator Pteris ensiformis at 10 µM AsV. Furthermore, compared to 500 µM phytate, the phytate concentration in the growth media was reduced by 69% to 155 µM, whereas the P and As contents in P. vittata fronds and roots were enhanced by 68-134% and 44-81% to 2423-2954 and 82-407 mg kg-1 under 500 µM phytate plus 50 µM AsV. The increased P/As uptake in P. vittata was probably attributed to 3.0-4.5-fold increase in expressions of P transporters PvPht1;3-1;4. Besides, under As exposure, plant P may be converted to phytate in P. vittata roots, thereby increasing phytate's contents by 84% to 840 mg kg-1. Overall, our results suggest that As-induced phytate/phytase exudation and phytate-P uptake stimulate its growth and As hyperaccumulation by P. vittata.

Phytase-Producing Rahnella aquatilis JZ-GX1 Promotes Seed Germination and Growth in Corn (Zea mays L.).

Phytase plays an important role in crop seed germination and plant growth. In order to fully understand the plant growth-promoting mechanism by Rahnella aquatilis JZ-GX1, the effect of this strain on germination of maize seeds was determined in vitro, and the colonization of maize root by R. aquatilis JZ-GX1 was observed by scanning electron microscope. Different inoculum concentrations and Phytate-related soil properties were applied to investigate the effect of R. aquatilis JZ-GX1 on the growth of maize seedlings. The results showed that R. aquatilis JZ-GX1 could effectively secrete indole acetic acid and had significantly promoted seed germination and root length of maize. A large number of R. aquatilis JZ-GX1 cells colonized on the root surface, root hair and the root interior of maize. When the inoculation concentration was 107 cfu/mL and the insoluble organophosphorus compound phytate existed in the soil, the net photosynthetic rate, chlorophyll content, phytase activity secreted by roots, total phosphorus concentration and biomass accumulation of maize seedlings were the highest. In contrast, no significant effect of inoculation was found when the total P content was low or when inorganic P was sufficient in the soil. R. aquatilis JZ-GX1 promotes the growth of maize directly by secreting IAA and indirectly by secreting phytase. This work provides beneficial information for the development and application of R. aquatilis JZ-GX1 as a microbial fertilizer in the future.

Assessing the Involvement of Selected Phenotypes of Pseudomonas simiae PICF7 in Olive Root Colonization and Biological Control of Verticillium dahliae.

Pseudomonas simiae PICF7 is an indigenous inhabitant of the olive (Olea europaea L.) rhizosphere/root endosphere and an effective biocontrol agent against Verticillium wilt of olive (VWO), caused by the soil-borne fungus Verticillium dahliae. This study aimed to evaluate the potential involvement of selected phenotypes of strain PICF7 in root colonization ability and VWO biocontrol. Therefore, a random transposon-insertion mutant bank of P. simiae PICF7 was screened for the loss of phenotypes likely involved in rhizosphere/soil persistence (copper resistance), root colonization (biofilm formation) and plant growth promotion (phytase activity). Transposon insertions in genes putatively coding for the transcriptional regulator CusR or the chemotaxis protein CheV were found to affect copper resistance, whereas an insertion in fleQ gene putatively encoding a flagellar regulatory protein hampered the ability to form a biofilm. However, these mutants displayed the same antagonistic effect against V. dahliae as the parental strain. Remarkably, two mutants impaired in biofilm formation were never found inside olive roots, whereas their ability to colonize the root exterior and to control VWO remained unaffected. Endophytic colonization of olive roots was unaltered in mutants impaired in copper resistance and phytase production. Results demonstrated that the phenotypes studied were irrelevant for VWO biocontrol.

Research Note: Jejunum phosphatases and systemic myo-inositol in broiler chickens fed without or with supplemented phytase.

As a constituent of animal cells, myo-inositol (MI) has been hypothesized to be crucial in several metabolic and regulatory pathways. Recently, it was shown that dietary phytase contributes to release of MI from phytate in the poultry digestive tract, increasing its systemic concentrations. This study investigated the activities of phosphatases in the jejunum and systemic plasma MI concentration in broilers not supplemented or supplemented with phytase through analyses based on modifications from commercial enzyme activity kits. Three hundred sixty male Ross 308 broilers were randomly allocated to 24 pens (15 birds per pen) in 4 dietary groups. The positive control group was fed with an adequate basal diet. The negative control group (NC) was fed with a reduced level of P and Ca. Groups Phy1500 and Phy3000 were fed with the NC diet plus 1,500 or 3,000 FTU of phytase per kilogram of feed, respectively. One bird per pen was selected for the measurement of jejunal phosphatase activity; MI concentration in plasma, the liver, and the kidney; and key MI enzyme concentrations (liver inositol monophosphatase 1 [IMPase 1] and kidney myo-inositol oxygenase [MIOX]). Endogenous phytase and alkaline phosphatase activity as well as IMPase 1 and MIOX expression were not statistically different among the dietary groups. The supplementation of 1500 FTU of phytase per kilogram of feed resulted in increase of plasma (P < 0.001) and kidney (P < 0.05) but not liver MI concentrations. The results indicated that systemic MI might reflect MI released from dietary sources; however, it did not appear to change expression of enzymes related to endogenous MI synthesis in the liver and catabolism in the kidney. New and larger studies are necessary to reach stronger evidence on the effects of dietary phytase on intestinal and systemic MI concentrations in broilers.

Horizontal Stacking of PAPhy_a Cisgenes in Barley Is a Potent Strategy for Increasing Mature Grain Phytase Activity.

Mature grain phytase activity (MGPA) in the Triticea tribe cereals has evolved through gene duplications and neo-functionalization of the purple acid phosphatase phytase gene (PAPhy) in a common ancestor. Increased gene copy number of the PAPhy_a gene expressed during seed development has augmented the MGPA in cereals like rye and wheat. PAPhy_a phytase is highly stable and a potent enzyme in feed. However, barley only contains one HvPAPhy_a gene and the MGPA levels needs to be increased to substitute for the addition of microbial phytases to the feed. A substantial increase in MGPA for cisgenic barley was achieved with one extra homozygous HvPAPhy_a insert when the plants were grown in the greenhouse. In the current study, the stability of increased MGPA was confirmed in open field grown cisgenic barley. Furthermore, the gene dose response of phytase cisgenes from three different cisgenic barley plants were horizontally stacked. Cisgenic barley with 0, 1, 2, 3, 4, and 6 extra HvPAPhy_a inserts demonstrated a perfect positive linear correlation with the level of MGPA. The current study provides new insight into the potential of stacking of cisgenes in crops and suggests cisgene stacking as a versatile strategy for crop improvement.

Biodiversity and techno-functional properties of lactic acid bacteria in fermented hull-less barley sourdough.

The aim of this study was to characterize the biodiversity of lactic acid bacteria (LAB) isolated from spontaneously-fermented hull-less barley sourdough and to determine its technological properties. Biodiversity was investigated by analysis of colonies isolated from sourdough on four different agar media. Of the 80 isolates, 67 were rapidly pre-identified as LAB using Fourier transforms infrared spectroscopy (FTIR). As a result of cluster analysis, 32 lactic acid bacteria chosen from different branches were identified. According to the polymerase chain reaction (PCR) results, 9 different species were identified: Pediococcus (dominant species), Lactobacillus curvatus, Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus musae, Lactobacillus paralimentarius, Leuconostoc mesenteroides and Lactobacillus equigenerosi. The most species and strain diversity among the media was determined in ModMRS environment. Unlike other studies about hull-less barley, Lactobacillus equigenerosi was identified in this study. LABs were identified with salt and acid tolerance. Generally, different levels of antibacterial activity in these species were shown against (rope spoilage) food borne pathogens. The greatest antimicrobial effect was observed for Pediococcus acidilactici SAB26, Lactobacillus plantarum SAB15 and Pediococcus acidilactici SAB13 compared to the other strains. Pediococcus species were found to have the highest antifungal effect against Penicillium carneum, Aspergillus flavus and A. niger. The phytase activity of LAB, which increases mineral bioavailability, was observed to be highest in Lactobacillus plantarum, Pediococcus pentosaceus, and Leuconostoc mesenteroides.

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, ß-propeller phytases (ßPP), 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 ßPP phytases and in silico characterization of these enzymes indicated divergence among the catalytic activities. Predicted fungal ßPP 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 ßPP 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 ßPP phytases and HAP phytases.

Isolation and identification of lactic acid bacteria with phytase activity from sourdough.

Wholemeal bread is strongly recommended due to its nutritional value. However, whole-grain foods contain a high level of phytic acid, an antinutritional factor that decreases the mineral bioavailability. The objective of this study was isolation and identification of lactic acid bacteria with phytase activity to find a suitable starter for bread-making. Wheat-legume sourdoughs were prepared by the back-slopping procedure. Lactic acid bacteria were isolated from the sourdough of wheat flour-mung bean, and their phytase activity was tested in the solid and liquid media. Out of the nine phytase-active isolates in the solid medium, only three isolates produced extracellular phytase in the liquid medium with activity ranging from 16.3 to 53.2 (U/ml). These isolates belonged to species Weissella confusa mk.zh95 and Pediococcus pentosaceus. The highest phytase activity was found for Weissella confusa mk.zh95. Weissella confusa mk.zh95 is considered an interesting source of phytase during cereals and legumes fermentation which improves the bioavailability of minerals.

Molecular Advances on Phytases in Barley and Wheat.

Phytases are pro-nutritional enzymes that hydrolyze phytate and make associated nutrients, such as phosphorous, iron, and zinc, bioavailable. Single-stomached animals and humans depend on phytase supplied through the diet or the action of phytase on the food before ingestion. As a result, phytases-or lack thereof-have a profound impact on agricultural ecosystems, resource management, animal health, and public health. Wheat, barley and their Triticeae relatives make exceptionally good natural sources of phytase. This review highlights advances in the understanding of the molecular basis of the phytase activity in wheat and barley, which has taken place over the past decade. It is shown how the phytase activity in the mature grains of wheat and barley can be ascribed to the PAPhy_a gene, which exists as a single gene in barley and in two or three homeologous copies in tetra- and hexaploid wheat, respectively. It is discussed how understanding the function and regulation of PAPhy_a may support the development of improved wheat and barley with even higher phytase activity.

Exploitation of autochthonous Tuscan sourdough yeasts as potential starters.

The increasing demand for healthy baked goods boosted studies on sourdough microbiota with beneficial metabolic traits, to be used as potential functional starters. Here, yeast populations of traditional sourdoughs collected from four Tuscan bakeries were investigated. Among 200 isolated strains, 78 were randomly selected and molecularly characterized. Saccharomyces cerevisiae was dominant, representing the only species detected in three out of the four sourdoughs. The fourth one harbored also Kazachstania humilis. Inter-delta regions analysis revealed a high intraspecific polymorphism discriminating 16 biotypes of S. cerevisiae isolates, which clustered based on their origin. Representative isolates from each biotype group were individually used to ferment soft and durum wheat flour, aiming at evaluating their pro-technological, nutritional and functional features. During fermentation under standardized conditions, all strains were able to grow of ca. 2 log cycles, but only S. cerevisiae L10Y, D18Y and D20Y had a significantly shorter latency phase in both flours. Overall, the highest volumes were reached after 16 h of fermentation in both soft and durum fermented dough. S. cerevisiae D2Y produced the highest dough volume increase. K. humilis G23Y was the only strain able to increase the total free amino acids concentration of the doughs. Overall, values of phytase activity were significantly higher in durum compared to the corresponding soft fermented dough. K. humilis G23Y and S. cerevisiae D20Y, D24Y showed a threefold higher phytase activity than spontaneously fermented control, and the highest concentration of total phenols. Almost all the strains led to increases of antioxidant activity, without significant differences among them. Investigations on the resistance of the strains to simulated gastric and intestinal conditions, that is considered a pre-requisite for the selection of probiotics, revealed the ability to survive in vitro by many of the strains considered. This study proposed the best performing yeast strains selected among autochthonous sourdough yeasts based on their pro-technological, nutritional and functional traits to be used as starters for making sourdough baked goods or functional cereal-based beverages. Although some yeast strains combined several technological and nutritional traits, the association of more selected strains seemed to be a requisite to get optimal sourdough characteristics.

Phytase Activity in the Digesta from Different Parts of the Digestive Tract and Ileal Digestibility of Nutrients in Broilers Fed with Buckwheat Diets.

In the present study, the effects of dietary buckwheat on phytase activity in the digesta from different parts of the digestive tract, and ileal digestibility of nutrients were determined in broilers fed with buckwheat diets. Eighty male broilers (29-d-old) were divided into four groups (20 birds each), and were fed one of the following diets until they were 36-d-old: positive control (PC) diet formulated based on the NRC recommendations, negative control (NC) diet containing 0.15% lower non-phytate phosphorus (P) than that in the PC diet, and two other diets formulated by replacing corn in NC diet with either 20% non-germinated (BU) or germinated (GBU) buckwheat. At the age of 36 d, broilers were sacrificed to collect digesta from the crop, gizzard, duodenum, jejunum, ileum, and cecum. The activity of phytase was low in the PC and NC diets, which increased in the BU diet and increased further in the GBU diet. A similar trend was observed in the crop digesta; however, the phytase activity in the crop digesta of BU and GBU diets was marginally lower when compared with that in each diet. These values decreased sharply when the digesta moved to the gizzard, and then decreased gradually. The ileal digesta exhibited significantly low activity with negligible effect of dietary treatment. The result of two-way analysis of variance with germination and digestive tract parts as main factors showed that the effect of digestive tract parts and interaction between factors was significant on the phytase activity in digesta. The dietary BU and GBU did not affect the ileal crude protein digestibility; however, it increased the ileal phytate P digestibility. These results suggest that in broilers, the crop might be the primary site of phytate degradation by buckwheat phytase, and the buckwheat might have negligible adverse effect on ileal digestibility of nutrients.

Evaluation of the mature grain phytase candidate HvPAPhy_a gene in barley (Hordeum vulgare L.) using CRISPR/Cas9 and TALENs.

In the present study, we utilized TALEN- and CRISPR/Cas9-induced mutations to analyze the promoter of the barley phytase gene HvPAPhy_a. The purpose of the study was dual, validation of the PAPhy_a enzyme as the main contributor of the mature grain phytase activity (MGPA), as well as validating the importance of a specific promoter region of the PAPhy_a gene which contains three overlapping cis-acting regulatory elements (GCN4, Skn1 and the RY-element) known to be involved in gene expression during grain filling. The results confirm that the barley PAPhy_a enzyme is the main contributor to the MGPA as grains of knock-out lines show very low MGPA. Additionally, the analysis of the HvPAPhy_a promoter region containing the GCN4/Skn1/RY motif highlights its importance for HvPAPhy_a expression as the MGPA in grains of plant lines with mutations within this motif is significantly reduced. Interestingly, lines with deletions located downstream of the motif show even lower MGPA levels, indicating that the GCN4/SKn1/RY motif is not the only element responsible for the level of PAPhy_a expression during grain maturation. Mutant grains with very low MPGA showed delayed germination as compared to grains of wild type barley. As grains with high levels of preformed phytases would provide more readily available phosphorous needed for a fast germination, this indicates that faster germination may be implicated in the positive selection of the ancient PAPhy gene duplication that lead to the creation of the PAPhy_a gene.

The consequences of introducing stochasticity in nutrient utilisation models: the case of phosphorus utilisation by pigs.

Simulation models of nutrient utilisation ignore that variation in pig system components can influence the predicted mean and variance of the performance of a group of pigs. The objective of this study was to develop a methodology to investigate how variation in feed composition would (a) affect the outputs of a nutrient utilisation model and (b) interact with variation that arises from the traits of individual pigs. We used a P intake and utilisation model to address these characteristics. Introduction of stochasticity gave rise to a number of methodological challenges--for example, how to generate variation in both feed composition and pigs and account for correlations between ingredients when modelling variation associated with feed mixing efficiency. Introducing variation in feed composition and pig phenotype resulted in moderate decreases in mean digested, retained and excreted P predicted for a population of pigs and an increase in their associated CV. A lower percentage of pigs in the population were predicted to meet their requirements during the feeding period considered, by comparison with the no-variation scenario. Variation in feed ingredient composition contributed more to performance variation than variation due to mixing efficiency. When variations in both feed composition and pig traits were considered, it was the former rather than the latter that had the dominant influence on variability in pig performance. The developed framework emphasises the consequences of random variability on the predictions of nutrient utilisation models. Such consequences will have a significant impact on decisions about management strategies such as feeding that are subject to variation.

Impact of Enzymatic and Microbial Bioprocessing on Protein Modification and Nutritional Properties of Wheat Bran.

Besides providing dietary fiber, wheat bran is a recognized source of protein and is considered a very valuable substitute for other protein-rich sources in the food and feed industry. Nonetheless, several factors affect protein bioavailability, including bran's layered structure. This study showed the influence on the release and protein modification of wheat bran of different bioprocessing methods involving the activation of endogenous enzymes of bran, the addition of an enzyme mixture having carbohydrase activity, and microbial fermentation. Bioprocessing in acidic conditions significantly enhanced the solubilization of protein from wheat bran, reaching the highest value in the treatment where the sole endogenous protease activity was activated. Bioprocessing through controlled fermentation allowed a more intense proteolysis and strongly impacted the in vitro digestibility of proteins. The combined use of starter cultures and cell-wall-degrading enzymes was characterized by the highest increase of phytase activity and total phenols.

Phytase activity of lactic acid bacteria and their impact on the solubility of minerals from wholemeal wheat bread.

The objective of this study was to determinate phytase activity of bacteriocins producing lactic acid bacteria previously isolated from spontaneous rye sourdough. The results show that the highest extracellular phytase activity produces Pediococcus pentosaceus KTU05-8 and KTU05-9 strains with a volumetric phytase activity of 32 and 54 U/ml, respectively, under conditions similar to leavening of bread dough (pH 5.5 and 30 °C). In vitro studies in simulated gastrointestinal tract media pH provide that bioproducts prepared with P. pentosaceus strains used in wholemeal wheat bread preparation increase solubility of iron, zinc, manganese, calcium and phosphorus average 30%. Therefore, P. pentosaceus KTU05-9 and KTU05-8 strains could be recommended to use as a starter for sourdough preparation for increasing of mineral bioavailability from wholemeal wheat bread.

Phytase in non-ruminant animal nutrition: a critical review on phytase activities in the gastrointestinal tract and influencing factors.

This review focuses on phytase functionality in the digestive tract of farmed non-ruminant animals and the factors influencing in vivo phytase enzyme activity. In pigs, feed phytase is mainly active in the stomach and upper part of the small intestine, and added phytase activity is not recovered in the ileum. In poultry, feed phytase activities are mainly found in the upper part of the digestive tract, including the crop, proventriculus and gizzard. For fish with a stomach, phytase activities are mainly in the stomach. Many factors can influence the efficiency of feed phytase in the gastrointestinal tract, and they can be divided into three main groups: (i) phytase related; (ii) dietary related and (iii) animal related. Phytase-related factors include type of phytase (e.g. 3- or 6-phytase; bacterial or fungal phytase origin), the pH optimum and the resistance of phytase to endogenous protease. Dietary-related factors are mainly associated with dietary phytate content, feed ingredient composition and feed processing, and total P, Ca and Na content. Animal-related factors include species, gender and age of animals. To eliminate the antinutritional effects of phytate (IP6), it needs to be hydrolyzed as quickly as possible by phytase in the upper part of the digestive tract. A phytase that works over a wide range of pH values and is active in the stomach and upper intestine (along with several other characteristics and in addition to being refractory to endogenous enzymes) would be ideal.

Stable current outputs and phytate degradation by yeast-based biofuel cell.

In this paper, we report for the first time that Candida melibiosica 2491 yeast strain expresses enhanced phytase activity when used as a biocatalyst in biofuel cells. The polarization also results in an increase of the yeast biomass. Higher steady-state electrical outputs, assigned to earlier production of an endogenous mediator, were achieved at continuous polarization under constant load. The obtained results prove that the C. melibiosica yeast-based biofuel cell could be used for simultaneous electricity generation and phytate bioremediation. In addition, the higher phytase activity obtained by interruptive polarization suggests a new method for increasing the phytase yield from microorganisms.

Phytase activity in brown rice during steeping and sprouting.

Phytase in brown rice will be activated and accumulated during seed germination. Changes of phytase activity in brown rice during two stages of germination (steeping and sprouting) affected by process conditions were studied. It was shown that steeping led to significant decrease of phytase activity (p < 0.01), varying with steeping temperature and steeping medium composition. Steeping respectively in demineralized water, 0.5 mM CaCl2 and 0.1 M H2O2 at 20 °C for 24 h led to the lowest phytase activity in brown rice, which was only 25% of that in raw rice. At steeping stage, steeping media had no significant effect. During the sprouting stage, phytase activity increased with prolonged time and gradually reached stable levels, and with higher temperature in the range of 15-25 °C. Phytase activity in brown rice reached 320-340 U kg-(1) after 5 d sprouting. The evolution pattern of phytase activity during sprouting differed with the solutes previously used during steeping. Steeping either with CaCl2 or H2O2 caused a delay followed by a rapid activation of phytase, while for control, a gradual accumulation of phytase activity was observed. Compared with acidic and alkaline steeping solutions, demineralized water at neutral (6.8) pH provided the best pre-treatment prior to sprouting at 25 °C, to activate maximum levels of phytase. Extreme conditions, either strong acidic or alkaline inhibited activation of phytase, and changed appearance of brown rice kernel as well.

Effect of germination on the phytase activity, phytate and total phosphorus contents of rice (Oryza sativa), maize (Zea mays), millet (Panicum miliaceum), sorghum (Sorghum bicolor) and wheat (Triticum aestivum).

The effect of germination on the level of phytase activity and the contents of phytates and phosphorus of five Nigeria grown cereal grains was studied. The cereals screened were rice (Oryza sativa), maize (Zea mays), millet (Panicum miliaceum), sorghum (Sorghum bicolor) and wheat (Triticum aestivum). Phytase activity was high (0.21-0.67 U g(-1)) in all samples. Phytate content ranged between 5.6 and 6.2 mg g(-1) while total phosphorus content ranged between 3.3 and 4.3 mg g(-1). During germination, the level of phytase activity increased and reached its maximal value after seven (16-fold), six (5-fold), five (7-fold), seven (3-fold) and eight (6-fold) days of germination for rice, maize, millet, sorghum and wheat respectively. After this initial increase, phytase activity declined slightly (P < 0.05). The increase in phytase activity during germination was accompanied by a significant reduction in phytate (P < 0.05) and a small but significant increase in total phosphorus.