High Phytase Activity Research Articles

Purification and Biochemical Characterization of Phytase Enzyme from Lactobacillus brevis Isolated from Fresh Kashar Cheese

In the last 20 years, phytase enzyme has attracted the attention of scientists in the fields of environmental protection, nutrition and biotechnology. Myo-inositol hexaphosphate phosphohydrolase (phytase), which is a type of phosphatase enzyme, catalyzes the hydrolysis of phytate into less phosphorylated inorganic phosphates and phytate. Phytases of microbial origin are widely used in biotechnological applications (paper industry, feed industry, food industry and soil improvement).
 In the present study, phytase enzyme was partially purified from Lactobacillus brevis NM-34 strain isolated from fresh kashar cheese and the pH and temperature values at which the enzyme showed optimum activity were determined. L. brevis NM-34 showed a phytase activity of 243.80 U/mL as a result of ammonium sulfate precipitation. In the ammonium sulfate range (40-60%), where the highest phytase activity was observed, the protein concentration was measured as 0.989 mg/mL. Km and Vmax values of phytase enzyme were determined as 0.0146 mM and 1.6 µmol/min, respectively. The pH and temperature values at which the partially purified phytase showed optimum activity were found to be pH 5 and 50 °C, respectively. Based on the findings from our research, the enzyme purified from this bacterium was found to have unique properties that make it suitable for use in industrial applications.

Research Note: Evaluation of phytic acid disappearance, ileal P digestibility, and total tract P retention in canola meal supplemented with increasing levels of exogenous phytase using conventional and cecectomized precision-fed roosters and growing chicks

Apparent ileal digestibility (AID) of P, apparent total tract retention (ATTR) of P, and phytic acid disappearance in canola meal were evaluated in the presence of increasing levels of exogenous phytase. In Experiment 1, a precision-fed rooster assay was used to determine phytic acid (myo-inositol 1,2,3,4,5,6-hexakis; InsP6) and inositol phosphate (InsP6-3; InsP-P) disappearance in conventional and cecectomized Leghorn roosters. Roosters were crop intubated with 25 g of canola meal mixed with 0, 500, 1,000, or 2,000 FTU/kg of exogenous phytase. In Experiment 2, InsP6 and InsP-P disappearance and AID and ATTR of P were determined using ad libitum-fed broiler chickens. Treatments consisted of semi-purified diets containing 45% canola meal as the sole source of P. Phytase was added to increase phytase activity by 0, 500, 1,000, or 2,000 FTU/kg. Experiments contained 6 replicates per treatment. Canola meal contained a high phytase activity (1,630 FTU/kg as-fed) due to contamination with a commercially available phytase at the feed mill from which the canola meal was sourced. In Experiment 1 with precision-fed roosters, there was no effect (P > 0.05) of phytase or bird type on InsP6 and InsP-P disappearance; however, phytase linearly reduced (P < 0.05) InsP3 concentrations in excreta. In Experiment 2 with ad libitum-fed chickens, phytase linearly increased (P < 0.05) ileal InsP6 and InsP-P disappearance, and phytase had a quadratic effect (P < 0.05) on excreta InsP6 and InsP-P disappearance. Increasing dietary phytase activity resulted in a linear increase (P < 0.05) in AID of P and phytase had a quadratic effect (P < 0.05) on ATTR of P. In conclusion, titration of high levels of phytase (1,600 to 3,600 FTU/kg as-fed) reduced InsP3 concentrations in precision-fed roosters but did not affect overall phytic acid hydrolysis, which was 78% or greater for all treatments; however, increasing the total phytase activity from 700 to 2,700 FTU in ad libitum-fed broiler chickens increased phytic acid disappearance and P digestibility.

Phytase Production by Lactobacillus plantarum A1-E in Submerged and Solid-State Fermentation

Enzyme activity is influenced by several important factors, including the amount and type of substrate, solvent type, pH, temperature, presence of inhibitory and activating ions, and concentration of enzymes. Therefore, this research aimed to evaluate phytase production from Lactobacillus plantarum A1-E using submerged (SmF) and solid-state fermentation (SSF). Phytase production was determined using SmF with fructose and sucrose as the primary carbon sources at concentrations of 4.5%, 6%, and 7.5%. Additionally, SSF was conducted using three distinct substrates, including soybean Meal, rice Bran, and pollard. The results indicated that the highest phytase activity was achieved through SSF when rice bran was used as a substrate (88.48 U/mL or 4.65 U/mg). The use of 4.5% sucrose as a carbon source in the SmF technique showed the highest specific phytase activity (4.38 U/mg) compared to other carbon sources at various concentrations. The addition of metal ions showed that Fe 2+ , Mn 2+ , and Co 2+ at concentrations of 1-5 mM, Mg 2+ and Zn 2+ at concentrations of 3-5 mM, and Ca 2+ at a concentration of 3 mM acted as activators that increased phytase activity compared to control. Meanwhile, Mg 2+ and Zn 2+ at concentrations 1-2 mM were inhibitors.

Effect of Bacillus cereus mutant strain S458-M on active phosphorus and crucian carp in culture systems

Certain bacterial strains could efficiently improve the conversion of insoluble phosphorus to active phosphorus due to their phosphate-solubilizing ability, but there is little research on its specific effects on aquaculture. In this study, a mutant strain Bacillus cereus S458-M was obtained via compound mutagenesis of UV and LiCl. We found it exhibited higher phosphate-solubilizing ability and phytase activity than the original strain S458-1 reported in our previous report. The sequence analysis of phytase gene (phyC) in S458-M revealed mutations in amino acids 81, 89 and 148. Its predicted protein contained an additional Ca2+ binding site that might be associated with higher phytase activity. To verify phosphate-solubilizing and probiotic properties of S458-M, no bacteria (CG: control group), S458-1 (LS: 1 × 105 CFU/mL; HS: 1 × 107 CFU/mL) and S458-M (LM: 1 × 105 CFU/mL; HM: 1 × 107 CFU/mL) were supplemented into aquaculture water separately. The results showed that S458-M could improve the concentration of active phosphorus in aquaculture water and enhance the antioxidant ability of crucian carp. Overall, S458-M obtained by UV-LiCl mutagenesis could support the application of phosphate-solubilizing bacteria in aquaculture water.

Phytase production by white-rot fungi cultivated in liquid medium with particulate agro-industrial byproducts

This study aimed to screen phytase-producing basidiomycetes by submerged cultivation (SmC) with particulate agro-industrial byproducts and evaluate the enzyme's thermal and pH stability. Five among eight fungal species produced high phytase activity (&gt; 300 U mL-1) after seven days in SmC. Ganoderma sp., the best phytase producer (1130 U mL-1), was grown in a liquid medium with particulate agro-industrial byproducts (coffee husks, citric pulp, sugarcane bagasse, and soybean hulls). Soybean hulls increased phytase activity (16%) and productivity (2.3-fold). The residual phytase activity was determined after 120 min incubation in different pH (pH 3, 5, 7, and 9) and temperatures (30, 50, and 70 oC). Phytase activity remained stable at pH ranging from 3 to 9, with 100% activity retention after 120 min at pH 7. Furthermore, Phytase retained more than 60% activity when incubated for 120 min from 30 oC to 70 oC. Our findings support future studies using Ganoderma sp. and particulate soybean hulls for phytase production for potential use in the animal feed industry.

Genomic and metabolomic profiling of endolithic Rhodococcus fascians strain S11 isolated from an arid serpentine environment.

Genomic and metabolomic studies of endolithic bacteria are essential for understanding their adaptations to extreme conditions of the rock environment and their contributions to mineralization and weathering processes. The endoliths of arid serpentine rocks are exposed to different environmental stresses, including desiccation and re-hydration, temperature fluctuations, oligotrophy, and high concentrations of heavy metals. Bacteria of the genus Rhodococcus commonly inhabit endolithic environments. Here, we describe genomic and metabolomic analyses of the non-pathogenic wild-type Rhodococcus fascians strain S11, isolated from weathered serpentine rock at the arid Khalilovsky massif, Russia. We found that strain S11 lacks the virulence plasmid that functions in the phytopathogenecity of some R. fascians strains. Phenotypic profiling revealed a high pH tolerance, phytase activity and siderophore production. A widely untargeted metabolome analysis performed using an Orbitrap LC-MS/MS method demonstrated the presence of chrysobactin-type siderophores in the culture medium of strain S11. The natural variation of secondary metabolites produced by strain S11 might provide a practical basis for revealing antibacterial, fungicide or insecticidal activities. Finally, plant infection and plant growth stimulation studies showed no observable effect of exposure strain S11 bacteria on the aerial and root parts of Arabidopsis thaliana plants. Based on our findings, R. fascians strain S11 might be promising tool for investigations of organo-mineral interactions, heavy metal bioremediation, and mechanisms of bacterial mediated weathering of plant-free serpentine rock to soil.

The effect of different compositions of starter cultures developed from phytic acid-degrading lactic acid bacteria on the sensory quality of bread

Sourdough is an initial product used in cereal fermentation, usually prepared by adding lactic acid bacteria (LAB) strains to a mixture of wheat and water. Phytic acid present in wheat flours negatively affects the bioavailability of bread. LAB is found to have phytase activity. The present work thus aimed to determine the effect of starter culture combinations developed from phytic acid-degrading LAB (PAD-LAB) strains isolated from sourdough samples on bread sensory quality. De Man, Rogosa, and Sharpe (MRS) agar, MRS Broth, M17 agar, M17 broth, sodium phytate, and mass spectrometry were used to isolate and identify PAD-LAB from sourdough samples. The extracellular phytase activity of PAD-LAB strains was determined by spectrophotometry. Sourdough samples were prepared using different strains having high phytase activity, and breads produced from these samples were evaluated using sensory attributes. Extracellular phytase activities of 30 strains were determined by the spectrophotometric method, showing the highest value at 1109.7 U/mL, and lowest at 386.9 U/mL, with a mean of 685.1 U/mL. Sourdough samples were prepared using five different strains with high phytase activity as starting cultures; and of the four sourdough samples selected, the count of LAB increased (7.80 - 9.87 log CFU/g), pH decreased (3.53 - 4.57), and TTA (total titratable acidity) values increased (10.17 - 14.29 mL) during the fermentation period. In the sensory evaluation, bread produced with starter culture combination CS30 was preferred. In conclusion, it was determined that the bread produced with PAD-LAB strains has an advantage in terms of sensory quality as compared to the control samples.

Evaluation of select biochars and clays as supports for phytase to increase the fertilizer potential of animal wastes

Manures may contain considerable amounts of organophosphates (org-P) that must be enzymatically converted to inorganic phosphate (i.e., PO4-P) to be plant available. Although adding enzymes into manures can facilitate mineralization of org-P to PO4-P, enzymes that are not immobilized are easily lost through leaching, degradation, or denaturation. In this study, the immobilization of enzymes onto nine different biochar surfaces was explored. Phytase, which mineralizes a main class of org-P, was used as the model enzyme. Immobilization methods included covalent grafting accomplished by the carbodiimide crosslinker method and physical sorption. The results showed that physisorption was as effective as grafting for loading phytase to the biochars. Phytase loading after mixing 0.1 g biochar and 2 mg phytase correlated positively with biochar C:H ratio (an indicator of aromatic content) suggesting the importance of the hydrophobic effect. An increase in pH led to a decrease in phytase loading consistent with repulsion between negatively charged sites on phytase and the increasing negative charge on biochar. Less than 4% of the immobilized phytase leached after sequential extractions over seven days using manure dissolve organic matter solutions. However, the activity of immobilized phytase decreased markedly compared to the free state phytase. The specific activity of immobilized phytase was two orders of magnitude lower than that of free phytase at pH 5 and 7. Nevertheless, results showed that deactivation of phytase by biochars were reversible once the phytase was detached from the surfaces. Compared to the biochars, clay minerals (montmorillonite, kaolinite and hematite) tended to have greater loading rates and higher phytase activity. Composting manures with coamendments of biochar and minerals may enhance both short- and long-term P mineralization potential.

Valorization of Lignocellulosic Wastes to Produce Phytase and Cellulolytic Enzymes from a Thermophilic Fungus, Thermoascus aurantiacus SL16W, under Semi-Solid State Fermentation.

Agricultural wastes are lignocellulosic biomasses that contain high mineral and nutrient contents. This waste can be used as a raw material in industrial enzyme production by microbial fermentation. Phytase is an important enzyme used in animal feed to enhance the amount of phosphorus available for the growth and overall health improvement of monogastric animals. Fungi offer high potential as an effective source in the production of various extracellular enzymes. In this study, the production of lignocellulolytic enzymes (endoglucanase and xylanase) and phytase by a thermophilic fungus, namely Thermoascus aurantiacus strain SL16W, was evaluated using sixteen different Thai agricultural forms of waste under conditions of high temperature (45 °C). Semi-solid state fermentation was used in the production experiments. The results of this study reveal that the highest phytase activity (58.6 U/g substrate) was found in rice bran, whereas the highest degrees of activity of endoglucanase and xylanase were observed in wheat bran and red tea leaves at 19 and 162 U/g substrate, respectively. Consequently, the optimal conditions for phytase production of this fungus using rice bran were investigated. The results indicate that the highest phytase yield (58.6 to 84.1 U/g substrate) was observed in rice bran containing 0.5% ammonium sulfate as a nitrogen source with 10 discs of inoculum size at a cultivation period of 9 days at 45 °C and moisture content of 95%. Notably, the phytase yield increased by 1.71-fold, while endoglucanase and xylanase were also increased by 1.69- and 1.12-fold, respectively. Furthermore, the crude enzyme obtained from the optimal condition was extracted. The crude enzyme extract was then separately added to red tea leaves, rice straw, corncobs, palm residue, and peanut husks. Subsequently, total reducing sugar and phosphorus contents were determined. The results indicate that the highest level of reducing sugar (122.6 mg/L) and phosphorus content (452.6 mg/L) (p < 0.05) were obtained in palm residue at 36 and 48 h, respectively, after the addition of the crude enzyme extract. This study has provided valuable information on a potentially eco-friendly way to valorize agricultural waste into value-added products as industrial enzymes.

Production of a ruminal bacterial phytase in the green microalga Chlamydomonas reinhardtii with potential applications in monogastric animal feed

Phytases are phosphatases employed in monogastric animal feed to improve animal growth rates and protect the environment by reducing phosphorous in manure. In this study, the highly active phytase PhyAsr of the protein tyrosine phosphatase class, which was derived from the ruminal bacterium Selenomonas ruminantium, was successfully produced for the first time in the chloroplast of the green microalga Chlamydomonas reinhardtii. Two homoplasmic lines (C1 and C3) exhibited the highest level of PhyAsr expression, while the highest phytase activity was detected in the C1 line at 34 U/g dry weight. The results of this study indicate that C. reinhardtii is a suitable host for producing the phytase PhyAsr, which may be utilized as a supplement in the monogastric animal diet.

Isolation and identification of phytate-degrading yeast from traditional fermented food

Abstract. Suryani AE, Anggraeni AS, Istiqomah L, Damayanti E, Karimy MF. 2021. Isolation and identification of phytate-degrading yeast from traditional fermented food. Biodiversitas 22: 866-873. Application of phytase (myo-inositol hexakisphosphate phosphohydrolase) to catalyze the release of phosphate from phytates contained on grain-based feed has been used widely in poultry feed industry. In this study, yeast as phytase producer from traditional fermented food was isolated, screened and identified their morphological, biochemical, and molecular characteristics. Production of extracellular phytase from yeast was quantified using spectrophotometer. The results showed that among 8 yeast isolates that had phytase activity, there were two isolates with the highest phytase activity and specific activity which were TKd3 isolate (6.57 U/mL and 54.230 U/mg) and GF1 (6.07 U/mL and 53.68 U/mg). Morphological identification using Scanning Electron Microscope revealed that TKd3 cells isolated from soybean tempeh had an elongated oval cell structure, whereas the GF1 isolated from fresh gatot had a rounder cell structure. TKd3 isolate with accession number MW131530 had homology with Candida tropicalis ATCC 750 28S rRNA with 99.83% similarity and GF1 isolate with accession number MW131531 had homology with Candida tropicalis ATCC 750 28S rRNA with 100% similarity. It could be concluded that C. tropicalis yeast from traditional fermented food produced the extracellular phytase for further use of phytase in poultry feed additive.

Effect of pH on Different Strains of Phytase Producing Bacteria from Malaysia’s Hot Spring

In the recent research, the optimisation of culture condition for phytase production rarely done for Acetinobacter baumanii. The optimisation of the phytase production from the bacterial strains largely contributed by Bacillus sp. The study on the phytase originated from hot spring are limited and the species that identified from the hot spring samples are not in the same species from the previous study and mainly the species isolated from Bacillus sp. In this study, four potential strains of bacteria producing phytase isolated from hot spring in several regions in Malaysia. For enrichment of the bacterial, Nutrient Agar was used, meanwhile for batch culture optimisation, the bacteria producing phytase grown in modified liquid Phytase Screening Media with soy extract as agro residual substrate as a replacement for sodium phytate, the chemical substrate. The bacteria were screened for their ability to produce clear zone in solid PSM with sodium phytate as substrate. Optimisation of media through its physical factor that is pH of the media carried out using shake flask scale in laboratory. The growth of the bacterial strains and phytase activity measured quantitatively through the two different pH of media at pH 5.5 and pH 7. The analysis of colony-forming unit and pH determination after fermentation was carried out in this study. From the study, bacterial strain L3 from Labis, Johor has the highest phytase activity in the two parameters studied where the inorganic phosphate released at pH 5.5 (0.21953 U/mL) and pH 7 (0.2047 U/mL). Optimisation carried out through manipulating the culture condition that is pH of the media to determine at which condition has the highest phytase production. Several effects on enzyme activity caused by culture conditions identified. The optimisation of the fermentation medium able to contribute to the less cost production of the industrial enzyme as phytase has potential production for feed additives for poultry feeding. In the future research, molecular identification of the bacterial strains from the better-quality bacteria producing phytase grown in optimised culture media to investigate the molecular identity of the bacterial.

Thermophilic lactic acid bacteria affect the characteristics of sourdough and whole-grain wheat bread

Application of selected starter cultures for sourdough propagation may ensure stable lactic acid bacteria (LAB) diversity and defined properties of sourdough that affect quality. The impact of Lactobacillus delbrueckii ssp. bulgaricus MI, L. rossiae GL14 and L. acidophilus DSM 20079 as starter cultures were investigated for spoilage prevention and whole-grain wheat and sourdough bread properties. Whole-grain wheat sourdough propagated with these strains showed high phytase, amylase and xylanases activities. The highest phytase activity was obtained in sourdough prepared with L. bulgaricus MI. The results of gas chromatography–mass spectrometry using solid-phase microextraction showed that the compositions of volatile compounds in sourdough and whole-grain wheat bread depended on the LAB starter. In bread with L. acidophilus, 3-octen-2-ol and n-hexadecane were found, whereas those compounds were not found in other bread samples or in sourdough. Tetrahydrofurfuryl acetate was found only in bread prepared with L. bulgaricus MI sourdough. N-Pentadecane was found only in bread prepared with L. rossiae sourdough and bread prepared with spontaneous sourdough. The application of thermophilic sourdough increased bread porosity, elasticity, crumbliness and moisture content, but did not influence crumb hardness. Moreover, the fungal spoilage on the bread crust surface was suppressed using sourdough prepared with thermophilic LAB. The strain of LAB used for sourdough preparation influenced the shelf-life of bread.

Selection of cereal-sourced lactic acid bacteria as candidate starters for the baking industry.

The quality of sourdough bread mainly depends on metabolic activities of lactic acid bacteria (LAB). The exopolysaccharides (EPS) produced by LAB affect positively the technological and nutritional properties of the bread, while phytases improve the bioavailability of the minerals by reducing its phytate content. In the present study, a pool of 152 cereal-sourced LAB were screened for production of phytases and EPS for potential use as sourdough starter cultures for the baking industry. There was large heterogeneity in the phytase activity observed among the screened isolates, with 95% showing the ability to degrade sodium phytate on plates containing Sourdough Simulation Medium (SSM). The isolates Lactobacillus brevis LD65 and Lactobacillus plantarum PB241 showed the highest enzymatic activity, while the isolates ascribed to Weissella confusa were characterized by low or no phytase activity. Only 18% of the screened LAB produced EPS, which were distinguished as ropy or mucoid phenotypes on SSM supplemented with sucrose. Almost all the EPS producers carried one or more genes (epsD/E and/or epsA) involved in the production of heteropolysaccharides (HePS), whereas the isolates ascribed to Leuconostoc citreum and W. confusa carried genes involved in the production of both HePS and homopolysaccharides (HoPS). Monosaccharide composition analysis of the EPS produced by a selected subset of isolates revealed that all the HePS included glucose, mannose, and galactose, though at different ratios. Furthermore, a few isolates ascribed to L. citreum and W. confusa and carrying the gtf gene produced β-glucans after fermentation in an ad hoc formulated barley flour medium. Based on the overall results collected, a subset of candidate sourdough starter cultures for the baking industry was selected, including Lb. brevis LD66 and L. citreum PB220, which showed high phytase activity and positive EPS production.

The molecular and technological characterization of lactic acid bacteria in einkorn sourdough: effect on bread quality

This study aimed to investigate the characterization of lactic acid bacteria strains (LABs) in spontaneous sourdough produced from einkorn flour as a new sourdough source and to determine some quality characteristics of sourdough bread. Thirty-two different LABs were isolated from spontaneously fermented einkorn sourdough under laboratory conditions. Seven different lactic acid bacteria strain (LAB) species, Lb. crustorum (dominant species 10), Pediococcus (4), Lb. brevis (6), Lb. paraplantarum (1), Lb. plantarum (5), Lb. fermentum (4), and Lb. curvatus (2) were identified by PCR (16S). Lb. paraplantarum and P. acidilactici showed high antibacterial activity against B. subtilis ATCC6633, B. cereus ATCC11778, and E. coli ATCC25922, and Lb. crustorum MN047 and L. brevis R-1 showed an antifungal effect on P. carneum, A. flavus, and A. niger. At the same time, all strains showed an acid-tolerant effect, because they showed a survival ratio higher than 70% at pH 2.5. The highest phytase activity was observed from L. paraplantarum 2815 and L. plantarum AAS3. The study aimed to investigate Lb. brevis R-1 and Lb. paraplantarum 7285 starter culture effects and bread quality parameters on dough made solely with einkorn or with a mixture of 25%, 50%, or 75% einkorn flour, compared to a solely wheat flour sourdough. The sourdough bread containing 25% and 50% einkorn flour had better volume, specific volume, and textural properties than bread containing 75% and 100% einkorn flour; they were scored as good as 100% wheat dough bread in terms of sensory properties. This study recommends that einkorn sourdough could be utilized as a beneficial source, having a diverse range of LABs and strong technological properties.

Characterization of Arabidopsis thaliana Plants Expressing Bacterial Phytase

Transgenic plants containing genes of bacterial phytases represent one of the promising ways to solve the problem of phosphorus deficiency in the nutrition of plants and monogastric animals. Histidine acid phytase PaPhyC from Pantoea agglomerans has a high activity and represents a promising basis for the biotechnology of plants. In this study, the analysis of morphological characteristics, phytase activity, and phosphorus content in tissues of the earlier obtained, genetically modified Arabidopsis thaliana (L.) Heynh. plants producing extracellular phytase (PaPhyC) has been carried out. According to the obtained results, modified plants are able to grow on a medium supplemented with phytate as the sole source of phosphorus. Exterior characteristics (rosette diameter and area) of phytase-expressing plants grown on media containing phytate or inorganic phosphorus do not differ, which confirms that the plants use phytate as the phosphorus source. In the case of plant cultivation on a phytate-containing medium, a high phytase activity is observed in the cell walls of modified plants. The content of inorganic phosphorus in tissues of modified plants does not change in the case of their cultivation on the medium containing phytate as the sole source of phosphorus.

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.

The Soybean Purple Acid Phosphatase GmPAP14 Predominantly Enhances External Phytate Utilization in Plants.

Induction and secretion of acid phosphatases (APases) is considered to be an important strategy for improving plant growth under conditions of low inorganic phosphate (Pi). Purple acid phosphatases (PAPs), are an important class of plant APases that could be secreted into the rhizosphere to utilize organic phosphorus (Po) for plant growth and development. To date, only a few members of the PAP family have been identified in soybean. In this paper, we identified a secreted PAP in soybean, GmPAP14, and investigated its role in utilizing external phytate, the main form of organic phosphorus in the soil. An analysis of its expression and promoter showed that GmPAP14 was mainly expressed in the root and was strongly induced following Po treatment, during which its expression expanded from meristematic to maturation zones and root hairs. In vitro enzyme assays indicated that GmPAP14 had a relatively high phytase activity. Furthermore, GmPAP14 overexpression increased secreted APase activities and phytase activities, leading to the improved use of external plant phytate, higher phosphorus content, and increased shoot weight. Thus, these results confirmed that GmPAP14 is an important gene induced in response to Po, and that it predominantly participates in utilizing external Po to enhance plant growth and development.

Biodegradative Potentials of Phytase-producing Bacterial Isolates Recovered from Spent Engine Oils Polluted-Soils

Microbial remediation of environmental contaminants such as spilled and used petroleum products is an increasing auspicious technique, owing to its associated low-cost and eco-friendly outcomes compared to other methods. For this purpose, recovered bacteria isolates from contaminated soils in automobile workshops were screened for phytase activity and hydrocarbon biodegradative ability. Presumptive bacterium with inherently high phytase activity and biodegradative potential was further characterized using 16S rRNA gene sequence analysis. Soil total petroleum hydrocarbon (TPH) was determined using gas chromatographic technique (GC-FID). The identities of the isolates recovered from the samples include; <i>Bacillus subtilis, B. licheniformis, Pseudomonas aeruginosa, Escherichia coli, Corynebacterium variabilis, Micrococcus luteus and Proteus vulgaris</i>. Of all the isolates, <i>P. aeruginosa</i> had the highest phytase activity after 48 h of incubation whereas, <i>P. vulgaris</i> recorded the least phytase activity. <i>E. coli</i> and <i>B. subtilis</i> showed active phytase activity at pH 5.0 and 40°C. While <i>P. aeruginosa</i> exhibited proficient degrading ability on crude oil and spent engine oil at all days of incubation, <i>E. coli</i> and <i>C. variabilis</i> showed the most inaptitude. The 16S rRNA gene analysis shows that the isolate obtained from the automobile workshop is of the genus <i>P. aeruginosa</i> with reference to ATCC 27853. The TPH of the contaminated soils ranged from 545,168 to 856,328 Mg/kg. This study reveals the degradative potential of <i>P. aeruginosa</i> as suitable candidate in bioremediation of crude oil contaminated sites.