Supplementation of alkaline phytase (Ds11) in whole-wheat bread reduces phytate content and improves mineral solubility

Abstract: In this study, alkaline phytase was added to whole‐wheat bread and the phytate content and mineral profiles were compared to commercially available acidic phytase. At neutral pH, some phytate (approximately 20%) was degraded by endogenous phytase in wheat flour, while 40% of phytate was hydrolyzed by alkaline phytase DS11 and a 35% reduction was observed with acidic phytase. Most of the enzymatic activity occurred during the proofing stage, and the rate of reaction depended on pH. DS11 phytase effectively degraded the phytate level within a 30 min treatment at pH 7; however, at least 60 min was needed with acidic phytase to achieve the same hydrolysis level. Mineral profiles were also dramatically affected by the phytate reduction. The biggest increase was observed in Fe²⁺ by the phytase treatment. The Fe²⁺ content increased 10‐fold at pH 7 and 8‐fold at pH 5 with alkaline phytase DS11. Alkaline phytase DS11 was shown to be effective at phytate reduction in whole‐wheat bread preparation. Additionally, phytate degradation enhanced the mineral availability of bread.     

Phytase Activity from Lactobacillus spp. in Calcium-Fortified Soymilk

Abstract: The presence of phytate in calcium-fortified soymilk may interfere with mineral absorption. Certain lactic acid bacteria (LAB) produce the enzyme phytase that degrades phytates and therefore may potentially improve mineral bioavailability and absorption. This study investigates the phytase activity and phytate degradation potential of 7 strains of LAB including: Lactobacillus acidophilus ATCC4962, ATCC33200, ATCC4356, ATCC4161, L. casei ASCC290, L. plantarum ASCC276, and L. fermentum VRI-003. Activity of these bacteria was examined both in screening media and in calcium-fortified soymilk supplemented with potassium phytate. Most strains produced phytase under both conditions with L. acidophilus ATCC4161 showing the highest activity. Phytase activity in fortified soymilk fermented with L. acidophilus ATCC4962 and L. acidophilus ATCC4161 increased by 85% and 91%, respectively, between 12 h and 24 h of fermentation. All strains expressed peak phytase activity at approximately pH 5. However, no phytate degradation could be observed.     

Peniophora lycii phytase is stabile and degrades phytate and solubilises minerals in vitro during simulation of gastrointestinal digestion in the pig

BACKGROUND: Microbial phytases (EC 3.1.3) are widely used in diets for monogastric animals to hydrolyse phytate present in the feed and thereby increase phosphorus and mineral availability. Previous work has shown that phytate solubility is strongly affected by calcium in the feed and by pH in the gastrointestinal (GI) tract, which may have an effect on phytase efficacy. An in vitro model simulating the GI tract of pigs was used to study the survival of Peniophora lycii phytase and the effect of the phytase on phytate degradation, inositol phosphate formation and mineral solubilisation during in vitro digestion of a 30:70 soybean meal/maize meal blend with different calcium levels. RESULTS: The phytase retained 76 and 80% of its initial activity throughout the gastric in vitro digestion. Total phytate hydrolysis by P. lycii phytase was in the same range at total calcium levels of 1.2 and 6.2 mg g^?1 dry matter (DM), despite very large differences in phytate solubility at these calcium levels. However, at 11.2 and 21.2 mg Ca g^?1 DM, phytate hydrolysis was significantly lower. The amount of soluble mineral was generally increased by P. lycii phytase. CONCLUSION: Stability of P. lycii phytase during gastric digestion was not found to be critical for phytate hydrolysis. Furthermore, original phytate solubility was not an absolute requirement for phytate degradation; phytate solubility seemed to be in a steady state, allowing insoluble phytate to solubilise as soluble phytate was degraded. This is new and interesting knowledge that adds to the current understanding of phytate–phytase interaction. Copyright © 2007 Society of Chemical Industry     

Determination of phytic acid in rapeseed meal

A new method has been developed for the determination of phytic acid in rapeseed meal based on extraction of the phytate with 15% trichloroacetic acid. After enzymatic hydrolysis with phytase from wheat, the phosphate is determined spectrophotometrically. The method has been applied to a number of varieties of rapeseed. The variation within a variety was nearly as high as within a population of varieties of the same species. The results imply that the phytic acid content of rapeseed is mostly influenced by environmental factors such as the availability of phosphorus in the soil.     

植酸酶在食品和医药方面的应用展望

从植酸及其盐类的抗营养作用出发，简单介绍了植酸酶的分类，来源，着重阐述了植酸酶在食品和医药方面应用及所面临的困难和应用前景。     

Purification and characterization of a novel thermostable phytase from the thermophilic Geobacillus sp. TF16

A novel phytase from thermophilic Geobacillus sp. TF16 was puri?ed approximately 5-fold using ammonium sulfate precipitation and ion exchange chromatography, and determined as a single band 106.04 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Optimum temperature and optimum pH were found to be 85°C and 4.0, respectively. The enzyme is highly thermostable and V_max and K_m values were calculated as 526.28 U/mg and 1.31 mM, respectively. It was also found that the enzyme exhibited a broad substrate selectivity and resistance toward proteases and effectively hydrolyzed soymilk phytate. These results suggest that this study provides an alternative phytase enzyme with enhanced properties.     

Bioavailability of Calcium Citrate Malate Added to Microbial Phytase-Treated, Hydrothermally Cooked Soymilk

Effects of microbial phytase on bioavailability of calcium added to corn/soy diets were investigated in chickens. No effect (P > 0.17) of phytase was found for weight gain, feed intake, tibia/body weight, ash%, and ash Ca% when calcium citrate malate (CCM) was added to corn/soybean meal and corn/hydrothermally cooked (HTC) soymilk diets. Using calcium carbonate in corn/HTC soymilk diets, means for weight gain, feed intake, tibia/body weight, and ash% were less (P < 0.05) without phytase. We hypothesize that CCM is less amenable to the formation of calcium phytate complexes than are other calcium salts and, therefore, should be more effective for fortification of soymilk products.     

目前国内外植酸酶研究进展

详细地介绍了植酸(盐)生化生理特性，综述了国内外植酸酶研究的概况及植酸酶添加到饲料中的主要功能，也指出了当前研究植酸酶的攻关方向。     

Phytic acid level in infant flours

This study determined the phytic acid content in the infant flour commonly consumed in the Canary Islands. A total of 400 samples from different cereals was analyzed. The method proposed by Garcı́a-Villanova et al. (1982) [Garcı́a-Villanova, R., Garcı́a-Villanova, R. J., Ruiz de Lope, C. (1982). Determination of phytic acid by complexometric titration of excess of iron (III). Analyst 107, 1503–1506] was the one used for determination of the phytic acid content in cereal flours. Phytic acid concentrations are within the range <1–⩾36 mg/g. The arithmetic mean obtained from all the samples studied is 24.6 mg/g. Most of the samples studied show a phytic acid content higher than 20 mg/g, and much lower values are observed in gluten-free flours (< 5 mg/g). Significant differences are observed for the different flour types. Gluten-free flour has a content lower than the rest; 9-cereal flour has a phytate concentration lower than the other flours tested but higher than gluten-free flour. Among wheat samples, phytate values are lower than in the varieties muesli-chocolate, 7-cereal, 8-cereal, multicereal and cereal-biscuit. Multicereal flour has a lower content than muesli-chocolate.     

Biochemical changes in phosphorus compounds and in the activity of phytase and α-amylase in the rice (Oryza sativa) grain during germination

Changes in the phytic acid, inorganic phosphorus and ATP contents, and in the activity of phytase and α-amylase in rice (Oryza sativa L) grains were determined during 18 days of germination in a dark room. The effect of phytic acid on α-amylase activity was studied in vitro. Rice grains immersed in sterilised deionised water at 14^°C germinated on the fifth day. Phytase activity, detected in the ripening rice grains, increased linearly until the eighth day and reached a maximum on the tenth day. There was a marked decrease in phytate and an increase in inorganic phosphorus accompanying germination. There was a good inverse correlation between the levels of both phytase activity and inorganic phosphorus, and phytate breakdown. α-Amylase activity was detected on the fourth day and increased markedly from the 12th to the 16th day of germination. ATP level increased from the second to the fourth day and slightly decreased from the fourth to the eighth day; it increased rapidly again from the eighth to the 18th day of germination. α-Amylase activity was influenced by both pH and phytic acid concentration in the assay system. At 75 mM phytic acid, α-amylase activity was lowered by 23%, 93% and 52% at pH 4–0, 5–0 and 6–0 respectively. When the enzyme, phytate and Ca²⁺ were incubated together at pH 5–0, the inhibition of α-amylase by phytic acid was markedly decreased by addition of Ca²⁺. The chemical affinity of Ca²⁺ for phytic acid was higher in the reaction at pH 5–0 than in those at pH 4–0 and pH 6–0, and over 98% of Ca²⁺ in the reaction system was precipitated as Ca-phytate.     

Selection of lactic acid bacteria with high phytate degrading activity for application in whole wheat breadmaking

Whole wheat products although highly recommended from the nutritional point of view, contain high levels of phytic acid, an antinutrient that decrease the mineral bioavailability. The objective of this study was to select strains with high phytate-degrading activity from different parts of the gastrointestinal tract of chickens following a phytate-rich diet and to test their suitability for the breadmaking process of whole wheat bread. Different lactobacilli and bifidobacteria strains were isolated and individually assayed for phosphatase and phytase activities, since both enzymes could contribute to the degradation of phytate. The isolates showing the highest phytate degrading activity belonged to the species Bifidobacterium dentium, Lactobacillus reuteri (L-M15) and Lactobacillus salivarius (L-ID15). The two lactobacilli L-M15 and L-ID15 were selected and tested their fermentative ability in whole wheat breadmaking. Whole wheat breads in the presence of the selected lactobacilli had similar technological quality than the control (in absence of lactobacilli) and extended freshness; moreover, their presence resulted in bread crumbs with lower levels of inositol phosphates. Overall, the two intestinal lactobacilli strains showing high phytate degrading activity were proven to have good properties for being used as starters in whole wheat breadmaking process.     

Determination of phytic acid in cereals – a brief review

Phytic acid is the major storage form for phosphorus in the cereal grains. It exists in the form of mixed salts of Ca–Mg–K (i.e. phytate), and occurs in many locations within the kernel. This form of phosphorus is not available to monogastric animals, including humans, because they lack the enzyme phytase in their digestive tract. In order to permit a better understanding of the functions and heritability of phytic acid, a literature search was conducted to review the development of procedures for the determination of phytic acid. Starting from a basic method of precipitation as insoluble ferric phytate in acid solution, the techniques for the determination of phytic acid have progressed through many kinds of instrumental methods such as colorimetric, synchronous fluorescence, isotachophoresis, high-performance ionic chromatography, and high-performance liquid chromatography.     

Mineral and Phytic Acid Partitioning Among Air-Classified Bean Flour Fractions

Hull flours and air-classified intermediate starch, high starch, and high protein navy, pinto, and black bean flours were analyzed for mineral content and phytic acid. Phytic acid content ranged from 4.29-8.72 mg/g in the high starch flours to 23.74-30.22 mg/g in the protein flours. Total phosphorus content proved to be a good indicator of phytic acid content. Zinc, iron, potassium, and magnesium partitioned into the protein flours of each bean type. Strong and significant correlation coefficients obtained between phytic acid content and the content of these minerals, and between the content of these minerals and protein content suggest that metallic phytate complexes were present.     

Phytic acid concentration in selected raw materials and analysis of its hydrolysis rate with the use of microbial phytases during the mashing process

Phytic acid present in the raw materials can complex with many compounds and therefore limit their availability to the yeast during the alcoholic fermentation process. An effective utilization of biogenic compounds bound in phytates requires a detailed analysis of the raw materials for their phytic acid content. The aim of this study was to characterize the major technological parameters for selected raw materials used in the distilling industry (maize, rye, wheat and triticale grain) and to determine the phytic acid content and the IP6/total phosphorus ratio. The phytic acid hydrolysis rate during the mashing process, with the use of microbial phytases, was analysed. The highest phytic acid concentrations (2.30 ± 0.20 mg/g dry matter) and the highest IP6/total P (80.42 ± 6.99%) were observed in the maize grain samples. Therefore, further studies on the phytic acid hydrolysis rate with the use of various phytases were conducted for the maize grain. The highest hydrolytic activity was observed for the Phytase 10000L preparation. This was the preparation that hydrolysed the phytic acid completely in up to 90 min. The application of a highly effective phytase, in ethanol production from maize grain, could lead to a more effective utilization of the biogenic compounds during the fermentation process. Copyright © 2015 The Institute of Brewing & Distilling     

Phytic acid interactions in food systems

Phytic acid is present in many plant systems, constituting about 1 to 5% by weight of many cereals and legumes. Concern about its presence in food arises from evidence that it decreases the bioavailability of many essential minerals by interacting with multivalent cations and/or proteins to form complexes that may be insoluble or otherwise unavailable under physiologic conditions. The precise structure of phytic acid and its salts is still a matter of controversy and lack of a good method of analysis is also a problem. It forms fairly stable chelates with almost all multivalent cations which are insoluble above pH 6 to 7, although pH, type, and concentration of cation have a tremendous influence on their solubility characteristics. In addition, at low pH and low cation concentration, phytate‐protein complexes are formed due to direct electrostatic interaction, while at pH >6 to 7, a ternary phytic acid‐mineral‐protein complex is formed which dissociates at high Na concentrations. These complexes appear to be responsible for the decreased bioavailability of the complexed minerals and are also more resistant to proteolytic digestion at low pH. Development of methods for producing low‐phytate food products must take into account the nature and extent of the interactions between phytic acid and other food components. Simple mechanical treatment, such as milling, is useful for those seeds in which phytic acid tends to be localized in specific regions. Enzyme treatment, either directly with phytase or indirectly through the action of microorganisms, such as yeast during bread‐making, is quite effective, provided pH and other environmental conditions are favorable. It is also possible to produce low‐phytate products by taking advantage of some specific interactions. For example, adjustment of pH and/or ionic strength so as to dissociate phytate‐protein complexes and then using centrifugation or ultrafiltration (UF) has been shown to be useful. Phytic acid can also influence certain functional properties, such as pH‐solubility profiles of the proteins and the cookability of the seeds.     

Effect of Phytic Acid on the In-Vitro Rate of Digestibility of Rapeseed Protein and Amino Acids

Phytic acid in rapeseed flour was reduced by pH adjustment to 5.15 with subsequent dialysis or by phytase treatment at pH 5.15 with subsequent dialysis. The effect of phytate reduction on the rate and extent of protein and amino acid digestibilities was then determined using an in vitro pepsin-pancreatin proteolysis method with simultaneous dialysis of reaction products. A 51% reduction in phytic acid increased the rate of release of many essential amino acids but a further 89% reduction in phytic acid did not enhance that effect. Phytate removal did not improve the protein digestibility.     

The Influence of Soaking and Germination on the Phytase Activity and Phytic Acid Content of Grains and Seeds Potentially Useful for Complementary Feedin

ABSTRACT: Phytic acid, a potent inhibitor of mineral and trace element absorption, occurs in all cereal grains and legume seeds. The possibility to increase phytase activity and/or reduce the phytic acid content by soaking and germination was investigated in a wide range of grains and seeds, but not found to be effective. Germination, but not soaking, increased phytase activity 3 to 5-fold in some cereal grains and legume seeds, while the influence on phytic acid content was insignificant in most materials tested. High apparent phytase activity was found in untreated whole grain rye, wheat, triticale, buckwheat, and barley. Their usefulness as sources of phytase in complementary food production should be further investigated.     

植酸/植酸钠在食品工业上的应用研究进展

植酸/植酸钠广泛存在于谷类、豆类和油料作物等中,应用非常广泛,在食品工业上可用作食品抗氧化剂、抑菌剂、护色剂、螯合剂和保鲜剂等。本文简述了植酸/植酸钠的结构、组成和理化特性,并且综述其在食品工业中的应用与研究进展。重点介绍了植酸/植酸钠在果蔬制品、饮料、发酵食品、酿造酒、油脂和脂肪制品、水产品、肉制品、焙烤制品和面制品等加工中的应用及研究进展。同时探讨了目前植酸/植酸钠在食品工业应用中存在的问题及解决对策,并对其发展趋势进行展望。指出目前高纯度植酸和固体植酸的生产成本较高,将来可以在植酸的色谱层析分离材料上进行改进。同时,为了增加植酸在油溶性食品中的应用范围,可以通过植酸的改性或借助于乳化、微乳化技术制备植酸/植酸钠的乳液和微乳液产品,是将来的发展方向。     

Potential for improvement in yeast nutrition in raw whole grain sorghum and maize lager brewing and bioethanol production through grain genetic modification and phytase treatment

Brewing and bioethanol production with raw grain and exogenous enzymes produces wort with satisfactory hot water extract (HWE). However, the free amino nitrogen (FAN) and mineral content can be too low, owing to low protein digestibility (PD) and phytate–mineral chelation, respectively. This study evaluated the potential for improvement in yeast nutrition in raw whole sorghum and maize brewing and bioethanol production by genetic modification (GM) of sorghum to improve PD and reduce phytate content, and by treatment with exogenous phytase. While phytase addition decreased sorghum spent grain phytate content (88%) and content of minerals (17 to 59%; i.e. increased wort mineral content), it did not affect maize phytate spent grain mineral content or HWE significantly. However, phytase addition did increase maize wort FAN (20%), sorghum HWE (2.8 percentage points) and wort FAN (23%). GM sorghum gave reduced spent grain mineral contents (11–38%), increased HWE (5.5 percentage points) and wort FAN (71%). Hence, genetic modification of sorghum to improve PD and reduce phytate content has considerable potential in raw grain brewing and bioethanol production to improve yeast nutrition. Copyright © 2012 The Institute of Brewing & Distilling     

Phytins?ure in Getreide und Getreideerzeugnissen

Zusammenfassung Phytinsäure in Lebensmitteln wird für eine verringerte Bioverfügbarkeit von essentiellen Mineralstoffen verantwortlich gemacht; sie kann während der Verarbeitung durch Phytase teilweise abgebaut werden. Der durchschnittliche Phytinsäuregehalt betrug in Roggen 8,18 mg/g und im Mehl der Type 997 3,44 mg/g; im Ganzkornmaterial wurden durchschnittlich Phytaseaktivitäten von 3,7 U/g und im Mehl 2,6. U/g gefunden. In den beiden Kornhälften (quergeteilt) waren Phytat und Phytase etwa gleichmäßig verteilt. Während der dreitägigen Keimung blieb die Phytaseaktivität konstant, der Phytinsäuregehalt nahm um ein Drittel ab. Bei der Vermahlung und dem Schälen von Roggen wurden die größten Mengen an Phytinsäure und Phytase mit Schrot- und Grießkleien bzw. Schälfraktionen entfernt. Es wird daraus geschlossen, daß Substrat und Enzym in den gleichen morphologischen Strukturen, wenn auch intrazellulär getrennt, vorkommen. Küchentechnische Zubereitungsformen von Vollkornprodukten waren für eine Phytatreduzierung um so wirkungsvoller, 1.) je feiner das Getreide vermahlen war, 2.) je mehr Wasser zugegeben wurde und 3.) je länger Phytase im optimalen Temperaturbereich einwirken konnte. Extrusion von Vollkornschrot bewirkte erst bei einer hohen Temperatur ( 170 °C) eine 23%ige Reduktion, während Phytase schon bei 80 °C um etwa 80% geschädigt wurde.

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Phytic acid in cerealsI. Phytic acid and Phytase in rye and rye products

Summary Phytic acid in food is considered to be responsible for a reduced bioavailability of essential dietary minerals; its detrimental effects can be diminished by hydrolysis with phytase during processing. The average phytic acid content was 8.18 mg/g and 3.44 mg/g and average phytase activity was 3.7 U/g and 2.6 U/g in rye kernels and in flour (Type 997, 1.09 ash content), respectively. Phytate and Phytase were about equally distributed between the two kernel halves (cross sections). During the early stages of germination (3 days) phytase activity did not change, and phytic acid content was reduced to 67%. After milling most of the phytic acid and phytase activity were found in the bran fractions. It is concluded that substrate and enzyme are present in the same kernel structures but separate within the cells. Cooking of ground rye caused a phytate hydrolysis which was the more effective 1.) the smaller the particle sizes were, 2.) the more water was added, and 3.) the longer phytase worked at optimum temperature. Extrusion cooking of the rye whole flour at up to 100 °C did not influence the phytic acid level but caused a 23% reduction at 170 °C. Phytase activity was reduced by 80% by extrusion cooking at 80 °C.

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Veröffentl.-Nr. 5342 der Bundesforschungsanstalt für Getreide-und Kartoffelverarbeitung, Detmold