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Ultrasonics Sonochemistry Jun 2024This study aimed to elucidate the impact of ultrasound-assisted cellulase (UC) pretreatment on nutrients, phytic acid, and the bioavailability of phenolics during brown...
This study aimed to elucidate the impact of ultrasound-assisted cellulase (UC) pretreatment on nutrients, phytic acid, and the bioavailability of phenolics during brown rice sprouting. It sought to unveil the underlying mechanisms by quantifying the activity of key enzymes implicated in these processes. The sprouted brown rice (SBR) surface structure was harmed by the UC pretreatment, which also increased the amount of γ-oryzanol and antioxidant activity in the SBR. Concurrently, the UC pretreatment boosted the activity of phytase, glutamate decarboxylase, succinate semialdehyde dehydrogenase, Gamma-aminobutyric acid (GABA) transaminase, chalcone isomerase, and phenylalanine ammonia lyase, thereby decreasing the phytic acid content and increasing the GABA, flavonoid, and phenolic content in SBR. In addition, UC-pretreated SBR showed increased phenolic release and bioaccessibility during in vitro digestion when compared to the treated group. These findings might offer theoretical direction for using SBR to maximize value.
Topics: Oryza; Phenols; Phytic Acid; Cellulase; Ultrasonic Waves; Antioxidants; Nutrients; Biological Availability
PubMed: 38669797
DOI: 10.1016/j.ultsonch.2024.106878 -
Nutrients Sep 2022Transition towards plant-based diets is advocated to reduce the climate footprint. Health implications of a diet composed of meat substitutes are currently unknown, and...
Transition towards plant-based diets is advocated to reduce the climate footprint. Health implications of a diet composed of meat substitutes are currently unknown, and there are knowledge gaps in their nutritional composition and quality. Samples of available meat substitutes were bought in two convenience stores in the city of Gothenburg, Sweden, and were included in the study. Meat substitutes (n = 44) were analyzed for their contents of dietary fiber, fat, iron, zinc, phytate, salt, total phenolics and protein, as well as for their amino acid and fatty acid composition. Bioavailability of iron and zinc was estimated based on the phytate:mineral molar ratio. We found large variations in the nutritional composition of the analyzed meat substitutes. Amino acid profiles seemed to be affected by processing methods. Mycoprotein products were rich in zinc, with a median content of 6.7 mg/100 g, and had very low content of phytate, which suggests mycoprotein as a good source of zinc. Degradability of fungal cell walls might, however, pose as a potential aggravating factor. None of the products could be regarded as a good source of iron due to very high content of phytate (9 to 1151 mg/100 g) and/or low content of iron (0.4 to 4.7 mg/100 g). Phytate:iron molar ratios in products with iron contents >2.1 mg/100 g ranged from 2.5 to 45. Tempeh stood out as a protein source with large potential due to low phytate content (24 mg/100 g) and an iron content (2 mg/100 g) close to the level of a nutrition claim. Producers of the products analyzed in this study appear to use nutritional claims regarding iron that appear not in line with European regulations, since the iron is in a form not available by the body. Meat substitutes analyzed in this study do not contribute to absorbed iron in a relevant manner. Individuals following mainly plant-based diets have to meet their iron needs through other sources. Salt and saturated fat were high in certain products, while other products were more in line with nutritional recommendations. Further investigation of the nutritional and health effects of protein extraction and extrusion is needed. We conclude that nutritional knowledge needs to be implemented in product development of meat substitutes.
Topics: Amino Acids; Biological Availability; Diet; Dietary Fiber; Fatty Acids; Humans; Iron; Meat; Phytic Acid; Sweden; Zinc
PubMed: 36235566
DOI: 10.3390/nu14193903 -
Scientific Reports Apr 2017Dicalcium phosphate cement preparation requires the addition of setting retarders to meet clinical requirements regarding handling time and processability. Previous...
Dicalcium phosphate cement preparation requires the addition of setting retarders to meet clinical requirements regarding handling time and processability. Previous studies have focused on the influence of different setting modifiers on material properties such as mechanical performance or injectability, while ignoring their influence on biological cement properties as they are used in low concentrations in the cement pastes and the occurrence of most compounds in human tissues. Here, analyses of both material and biological behavior were carried out on samples with common setting retardants (citric acid, sodium pyrophosphate, sulfuric acid) and novel (phytic acid). Cytocompatibility was evaluated by in vitro tests with osteoblastic (hFOB 1.19) and osteoclastic (RAW 264.7) cells. We found cytocompatibility was better for sodium pyrophosphate and phytic acid with a three-fold cell metabolic activity by WST-1 test, whereas samples set with citric acid showed reduced cell number as well as cell activity. The compressive strength (CS) of cements formed with phytic acid (CS = 13 MPa) were nearly equal to those formed with citric acid (CS = 15 MPa) and approximately threefold higher than for other setting retardants. Due to a proven cytocompatibility and high mechanical strength, phytic acid seems to be a candidate replacement setting retardant for dicalcium phosphate cements.
Topics: Animals; Biocompatible Materials; Bone Cements; Calcium Phosphates; Cell Culture Techniques; Cell Line; Cell Survival; Cells, Cultured; Dental Cements; Materials Testing; Mechanical Phenomena; Mice; Osteoblasts; Osteoclasts; Phytic Acid; RAW 264.7 Cells; Temperature; X-Ray Diffraction
PubMed: 28373697
DOI: 10.1038/s41598-017-00731-6 -
International Journal of Molecular... Jun 2022AppA, the periplasmic phytase of clade 2 of the histidine phosphatase (HP2) family, has been well-characterized and successfully engineered for use as an animal feed...
AppA, the periplasmic phytase of clade 2 of the histidine phosphatase (HP2) family, has been well-characterized and successfully engineered for use as an animal feed supplement. AppA is a 1D-6-phytase and highly stereospecific but transiently accumulates 1D--Ins(2,3,4,5)P and other lower phosphorylated intermediates. If this bottleneck in liberation of orthophosphate is to be obviated through protein engineering, an explanation of its rather rigid preference for the initial site and subsequent cleavage of phytic acid is required. To help explain this behaviour, the role of the catalytic proton donor residue in determining AppA stereospecificity was investigated. Four variants were generated by site-directed mutagenesis of the active site HDT amino acid sequence motif containing the catalytic proton donor, D304. The identity and position of the prospective proton donor residue was found to strongly influence stereospecificity. While the wild-type enzyme has a strong preference for 1D-6-phytase activity, a marked reduction in stereospecificity was observed for a D304E variant, while a proton donor-less mutant (D304A) displayed exclusive 1D-1/3-phytase activity. High-resolution X-ray crystal structures of complexes of the mutants with a non-hydrolysable substrate analogue inhibitor point to a crucial role played by D304 in stereospecificity by influencing the size and polarity of specificity pockets A and B. Taken together, these results provide the first evidence for the involvement of the proton donor residue in determining the stereospecificity of HP2 phytases and prepares the ground for structure-informed engineering studies targeting the production of animal feed enzymes capable of the efficient and complete dephosphorylation of dietary phytic acid.
Topics: 6-Phytase; Acid Phosphatase; Animals; Dinucleoside Phosphates; Escherichia coli; Escherichia coli Proteins; Phytic Acid; Prospective Studies; Protons
PubMed: 35683026
DOI: 10.3390/ijms23116346 -
International Journal of Food... Jan 2020Aiming at meeting the recommendations of the World Health Organization regarding the total fiber daily intake, an integrate biotechnological approach, combining xylanase...
Aiming at meeting the recommendations of the World Health Organization regarding the total fiber daily intake, an integrate biotechnological approach, combining xylanase treatment and lactic acid bacteria fermentation of milling by-products from pigmented wheat varieties, hull-less barley and emmer was proposed. The effects on the biochemical and nutritional features were investigated. Enhanced radical scavenging activity, increased concentrations of free amino acids (up to three times) and peptides and optimal in vitro protein digestibility (up to ca. 87%) value as well as relevant phytic acid degradation were achieved during bran fermentation. The main nutritional features of each matrix were enhanced and distinguished. Fortified breads were characterized by a concentration in total dietary fibers and protein of ca. 7 and 13% of dry matter, respectively. Compared to wheat bread the addition of pre-fermented brans caused a significant increase in protein digestibility (up to 79%), and a relevant decrease of the predicted glycemic index (ca. 8%) of the fortified bread. According to the results, this study demonstrates the potential of xylanase treatment and lactic acid bacteria fermentation to be used as suitable strategy to include bran in breadmaking, meeting both nutritional and sensory requests of modern consumers.
Topics: Biocatalysis; Bread; Dietary Fiber; Endo-1,4-beta Xylanases; Fermentation; Flour; Food Additives; Hordeum; Humans; Lactobacillaceae; Lactobacillales; Nutritive Value; Phytic Acid; Triticum; Waste Products
PubMed: 31670259
DOI: 10.1016/j.ijfoodmicro.2019.108384 -
Nutrition Reviews May 2014The most widely used method for estimating dietary zinc requirements is the factorial approach, in which it is assumed, in adults, that the physiological zinc... (Review)
Review
The most widely used method for estimating dietary zinc requirements is the factorial approach, in which it is assumed, in adults, that the physiological zinc requirement is the lowest intake that replaces endogenous zinc losses. Presented here are the results of two reviews: a narrative review of zinc losses from the human body and a systematic review of factors affecting zinc bioavailability in adult and elderly populations. The narrative review presents data on losses from integumental and excretory routes, obtained from 29 papers published up to April 2013. The systematic review includes a total of 87 publications describing dietary factors that impact zinc bioavailability, 30 of which examined phytate. A meta-analysis revealed an overall lowering of fractional zinc absorption by 0.14 (45% of control values) when the phytate : zinc molar ratio of the test meal or diet was greater than 15. These reviews provide a comprehensive resource for use in the setting of human dietary zinc requirements and emphasize the need for more high-quality data to improve estimates of zinc losses and gains.
Topics: Aging; Biological Availability; Diet; Humans; Intestinal Absorption; Nutritional Requirements; Phytic Acid; Zinc
PubMed: 24739133
DOI: 10.1111/nure.12105 -
The Journal of Nutrition Oct 2020Iron deficiency is a major public health concern in Ethiopia, where the traditional diet is based on tef injera. Iron absorption from injera is low due to its high...
BACKGROUND
Iron deficiency is a major public health concern in Ethiopia, where the traditional diet is based on tef injera. Iron absorption from injera is low due to its high phytic acid (PA) content.
OBJECTIVES
We investigated ways to increase iron absorption from FeSO4-fortified tef injera in normal-weight healthy women (aged 21-29 y).
METHODS
Study A (n = 22) investigated the influence on fractional iron absorption (FIA) from FeSO4-fortified injera of 1) replacing 10% tef flour with whole wheat flour (a source of wheat phytase), or 2) adding an isolated phytase from Aspergillus niger. Study B (n = 18) investigated the influence on FIA of replacing FeSO4 in tef injera with different amounts of NaFeEDTA. In both studies, the iron fortificants were labeled with stable isotopes and FIA was calculated from erythrocyte incorporation of stable iron isotopes 14 d after administration.
RESULTS
In study A, the median (IQR) FIA from the 100% tef injera meal was 1.5% (0.7-2.8%). This increased significantly (P < 0.05) to 5.3% (2.4-7.1%) on addition of 10% whole wheat flour, and to 3.6% (1.6-6.2%) on addition of A. niger phytase. PA content of the 3 meals was 0.62, 0.20, and 0.02 g/meal, respectively. In study B, the median (IQR) FIA from the 100% tef injera meal was 3.3% (1.1-4.4%) and did not change significantly (P > 0.05) on replacing 50% or 75% of FeSO4 with NaFeEDTA.
CONCLUSIONS
FIA from tef injera by young women was very low. NaFeEDTA was ineffective at increasing iron absorption, presumably due to the relatively low EDTA:Fe molar ratios. Phytate degradation, however, greatly increased during tef fermentation on addition of native or isolated phytases. Replacing 10% tef with whole wheat flour during injera fermentation tripled FIA in young women and should be considered as a potential strategy to improve iron status in Ethiopia.
Topics: Adult; Biofortification; Biological Transport; Cooking; Cross-Over Studies; Eragrostis; Female; Fermentation; Ferrous Compounds; Flour; Food, Fortified; Humans; Iron; Iron Isotopes; Phytic Acid; Triticum; Whole Grains; Young Adult
PubMed: 32805002
DOI: 10.1093/jn/nxaa211 -
Nature Structural & Molecular Biology Mar 2023HIV-1 Gag metamorphoses inside each virion, from an immature lattice that forms during viral production to a mature capsid that drives infection. Here we show that the...
HIV-1 Gag metamorphoses inside each virion, from an immature lattice that forms during viral production to a mature capsid that drives infection. Here we show that the immature lattice is required to concentrate the cellular metabolite inositol hexakisphosphate (IP6) into virions to catalyze mature capsid assembly. Disabling the ability of HIV-1 to enrich IP6 does not prevent immature lattice formation or production of the virus. However, without sufficient IP6 molecules inside each virion, HIV-1 can no longer build a stable capsid and fails to become infectious. IP6 cannot be replaced by other inositol phosphate (IP) molecules, as substitution with other IPs profoundly slows mature assembly kinetics and results in virions with gross morphological defects. Our results demonstrate that while HIV-1 can become independent of IP6 for immature assembly, it remains dependent upon the metabolite for mature capsid formation.
Topics: HIV-1; Capsid; Virus Assembly; Capsid Proteins; Phytic Acid; Virion
PubMed: 36624347
DOI: 10.1038/s41594-022-00887-4 -
STAR Protocols Mar 2021This protocol describes an affinity enrichment approach from mammalian cell extracts to identify protein binding partners of inositol hexakisphosphate (InsP) and...
This protocol describes an affinity enrichment approach from mammalian cell extracts to identify protein binding partners of inositol hexakisphosphate (InsP) and 5-diphosphoinositol pentakisphosphate (5PP-InsP), two important eukaryotic metabolites. The interactomes are annotated using mass spectrometry-based proteomics, and comparison against a control resin can uncover hundreds of protein targets. Quantitative analysis of InsP- versus 5PP-InsP-binding proteins highlights specific protein-ligand interactions. The approach is applicable to different cells and organisms and will contribute to a mechanistic understanding of inositol poly- and pyrophosphate signaling. For complete details on the use and execution of this protocol, please refer to Furkert et al. (2020).
Topics: HCT116 Cells; HEK293 Cells; Humans; Inositol Phosphates; Mass Spectrometry; Phytic Acid; Second Messenger Systems
PubMed: 33490990
DOI: 10.1016/j.xpro.2020.100277 -
PLoS Pathogens Jul 2010Large bacterial protein toxins autotranslocate functional effector domains to the eukaryotic cell cytosol, resulting in alterations to cellular functions that ultimately... (Review)
Review
Large bacterial protein toxins autotranslocate functional effector domains to the eukaryotic cell cytosol, resulting in alterations to cellular functions that ultimately benefit the infecting pathogen. Among these toxins, the clostridial glucosylating toxins (CGTs) produced by Gram-positive bacteria and the multifunctional-autoprocessing RTX (MARTX) toxins of Gram-negative bacteria have distinct mechanisms for effector translocation, but a shared mechanism of post-translocation autoprocessing that releases these functional domains from the large holotoxins. These toxins carry an embedded cysteine protease domain (CPD) that is activated for autoprocessing by binding inositol hexakisphosphate (InsP(6)), a molecule found exclusively in eukaryotic cells. Thus, InsP(6)-induced autoprocessing represents a unique mechanism for toxin effector delivery specifically within the target cell. This review summarizes recent studies of the structural and molecular events for activation of autoprocessing for both CGT and MARTX toxins, demonstrating both similar and potentially distinct aspects of autoprocessing among the toxins that utilize this method of activation and effector delivery.
Topics: ATP-Binding Cassette Transporters; Animals; Bacterial Toxins; Eukaryota; Humans; Phytic Acid
PubMed: 20628577
DOI: 10.1371/journal.ppat.1000942