Fraction Of Ca2 Research Articles

Lithology controlled soil organic carbon stabilization in an alpine grassland of the Peruvian Andes

Alpine grasslands of the Neotropical Andes have high soil organic carbon (SOC) stocks and provide crucial ecosystem services. However, stability of the SOC in these grasslands is not well-studied. Having insights into SOC stability contributes to a better understanding of ecosystem vulnerability and maintaining of ecosystem services. The objectives were to get a first insight into organic matter (OM) stabilization in soils from different bedrocks of Andean alpine grasslands near Cajamarca, Peru (7° 11″ S, 78° 35″ W) and how this controls SOC stocks. Samples were collected from soils formed on limestone and acid igneous rocks. Stabilization mechanisms of OM were investigated using selective extraction methods separating active Fe, Al and Ca fractions and determined SOC stocks. In both soil types, the results showed important contributions of complexation with and/or adsorption on Fe and Al (oxides) to OM stabilization. Exclusively in the limestone soils, Ca induced OM stabilization by promoting the formation of Ca2+ bridges between OM and mineral surfaces. Furthermore, no evidence showed that OM stabilization was controlled by crystalline Fe oxides, clay contents, allophones, Al toxicity or aggregate stability. Limestone soils had significantly higher SOC stocks (405 ± 42 Mg ha−1) compared to the acid igneous rock soils (226 ± 6 Mg ha−1), which is likely explained by OM stabilization related to Ca2+ bridges in addition to the stabilization related to Fe and Al (oxides) in the limestone soils. Our results suggest a shift from OM stabilization dominated by Fe and Al (oxides) to that with the presence of Ca-related cation bridges, with increasing pH values driven by lithology.

Phosphorus and zinc are less bioaccessible in soy-based beverages in comparison to bovine milk

Abstract Total contents and bioaccessible fractions of Ca, K, Mg, Na, P and Zn in bovine milk and soy-based were determined to investigate if this plant-based beverage could be an adequate substitute of bovine milk with relation to the ingestion of these essential elements. The quantification of the elements was made by inductively coupled plasma optical emission spectrometry (ICP OES) and their bioaccessibilities were evaluated by in vitro simulation of the human gastrointestinal digestion. Total contents of minerals were similar among the milk samples, whereas the concentrations determined in soy-based beverages exhibited more variability, mainly for Ca, P and Zn. All the evaluated elements presented bioaccessible fractions higher than 60% in bovine milk, whereas in the soy-based beverages bioaccessibilities lower than 30% were obtained for P and Zn. Special attention should be given for P and Zn intake in cases of substitution of bovine milk by soy-based beverages.

Adsorption Thermodynamics of Cu- Ca Ion Exchange on Nano-montmorillonite Clay System

ABSTRACT The ion exchange reaction between Ca-montmorillonite in a Nano form and copper ions is studied by the potentiometric methods using a glass electrode specific for copper ion determination at three different temperatures (20, 30 and 40°C). Ca-Clay + Cu2+ ⇌ Cu- Clay + Ca2+ Enhancement of the copper on the nano-montmorillonite was recorded with increasing the Cu ion fraction in the solution. Increasing the reaction temperature had a negative effect on the concentration of Cu fraction on the solid phase.The isotherms results pointed out that adsorption of Cu2+ ions are preferred as indicated by the negatively charged free energy (ΔGo). The preference for the Cu2+ ions and their influence on the nano-montmorillonite as well as the high binding strength are elucidated by the negativity of the entropy (∆S◦) and ∆Sclay as well as the enthalpy (∆H◦) values. The adsorption reactions of Cu2+ onto the clay surfaces were exothermic in nature as indicated by the negative value of ∆H◦. The activity coefficient of the exchanged ions at different ionic fractions Ca:Cu in the solution are affected mainly by two factors included the distribution of the ions in the Gouy and Stern layers and the differences in the interlayer spacing according the solution composition.

Combustion of Titanium Oxide Based Thermite Systems with a Complex Reducing Agent and an Energy Additive under the Influence of Overload

The laws and mechanism of combustion of TiO2 based thermite systems with a complex reducing agent (Al and Ca) under the influence of overload are revealed. The thermite system includes a basic composition whose combustion products are target elements (Ti, Al, Nb, and Cr) and a high-energy additive (CaO2, Al, and Ca) for ensuring high-temperature combustion. With the introduction of an energy additive, the system acquires the ability to burn. With a sufficient content of this additive, the combustion products (TixAly and Al2O3 and CaO oxide solutions) can melt. As the fraction of Ca in the base mixture composition increases, the burning rate drops and the reduction completeness of the target oxides increases. With an optimal ratio of Ca and Al in the mixture, the yield of the target elements in the ingot is close to the calculated value.

A unified 23Na NMR chemical shift correlation with structural parameters in multicomponent silicate‐based glasses

AbstractFrom a large ensemble of 34 silicate‐based glasses from the borosilicate, phosphosilicate, and borophosphosilicate systems that comprise either Na as a sole glass‐network modifier or when mixed with Ca, we established a good correlation between the 23Na average isotropic chemical shift () and the average coordination number of Na and the mean Na–O distance. The latter parameters were obtained by atomistic molecular dynamics simulations. We also demonstrated that is essentially independent on the precise network forming (Si, B, P) species but depends primarily on the net molar fraction of Na and Ca, thereby offering a straightforward 23Na chemical shift prediction from the glass composition alone.

Air pollution and particulate matter composition in relation to epigenetic age

OPS 48: Air pollution and epigenetics, Room 417, Floor 4, August 26, 2019, 4:30 PM - 5:30 PM Background. Air pollution is associated with numerous adverse health outcomes. Advanced epigenetic age, estimated using DNA methylation, may be a marker of biological consequences of prolonged air pollution exposure. Methods. In a sample of non-Hispanic white women ages 35-74 living in the contiguous U.S. (n=2,764), we estimated annual average ambient residential levels of PM2.5, PM10 and NO2 using a model combining land-use regression and kriging fit to regulatory monitoring data. Predictive k-means was used to assign participants to one of 7 clusters that corresponded to different relative combinations of PM2.5 components. We measured DNA methylation (DNAm) in blood samples using the Illumina’s Infinium HumanMethylation450 BeadChip and calculated DNAm age using the Levine/PhenoAge clock. Age acceleration was derived by regressing DNAm age on chronological age and calculating the residuals. Using linear regression models accounting for blood cell composition, we estimated adjusted associations between an interquartile range (IQR) increase in pollutants and age acceleration. We stratified the associations for PM2.5 by component cluster membership. Results. Higher age acceleration was observed for PM10 (β=0.24, 95% CI: 0.03, 0.46) but not for NO2. For PM2.5, we observed heterogeneity by component cluster membership (p for interaction=0.001). PM2.5 was associated with an almost 4-year higher age acceleration in a cluster characterized by higher relative fractions of crustal elements Si, Ca, K and Al (β=3.96, 95% CI: 0.72, 7.20), and an almost 2-year higher age acceleration in a cluster characterized by low sulfur fractions relative to overall PM2.5 (β=1.94, 95% CI: 0.41, 3.46). In contrast, PM2.5 was inversely associated with age acceleration in a cluster distinguished by low relative nitrite concentrations (β=-1.84, 95% CI: -3.19, -0.48). Conclusions. Air pollution was associated with epigenetic age, a marker of mortality and disease risk, with heterogeneity in the association between PM2.5 and epigenetic age acceleration by particulate matter composition.

Left atrium wall deformation properties

Mitral regurgitation is the second most frequent indication for valve surgery. The problem of a therapeutic decision during mitral valve insufficiency is quite timely. The unfavorable prognosis for disease depends largely on left ventricular dysfunction and levels of ventricular dysfunction are thoroughly studied. High level of ventricular dilation during mitral valve insufficiency is one surgical indication. Due to the fact that it is impossible to separate the contribution of coronary insufficiency and volume overload components to the process of left ventricular remodeling such parameters as ventricular size and left ventricular ejection fraction can't be used as parameters of hemodynamically relevant regurgitation. The role of the left atrium in global dilation of the heart against the backdrop of the mitral insufficiency is poorly studied. Left atrial dilation is powerful mortality prediction. It is well known that the atria contribution is essential to a ventricular ejection in the course of the left ventricular dysfunction. The strain and the strain rate of the left atrium are the prior markers of volume overload versus the dimensional changes. The computer tomography experiment of the left atrium property investigation was set up in the Federal Center of Cardiovascular Surgery Named after S.G. Sukhanov in Perm. The experiment data technique was developed. Quantitative characteristics of displacement and strain of the left atrium wall were obtained as a result of data conditioning. The properties of the left atrium wall were analyzed and stress–strain curves were plotted along and across muscle fibers for different parts of the wall. The shear strain was found in the tangent plane of the left atrium.

Behavior of calcium isotopes during continental subduction recorded in meta-basaltic rocks

In order to investigate the behavior of Ca isotopes during subduction, we report high precision Ca isotopic data of a suit of well-characterized meta-basaltic rocks from the Dabie-Sulu orogen, including six greenschists, six amphibolites and seven eclogites. Except two samples that may have been affected by carbonation alteration, greenschists, amphibolites and eclogites yield comparable δ44/42Ca values ranging from 0.36 to 0.41‰, 0.32 to 0.39‰ and 0.32 to 0.42‰, respectively. Overall, Dabie-Sulu meta-basaltic rocks have an average δ44/42Ca of 0.37 ± 0.06‰ (2SD, N = 17/19), comparable to terrestrial basalts previously reported (0.36 ± 0.05‰, 2SD; N = 34). Combined with no correlation of δ44/42Ca with H2O and Rb/TiO2, this study suggests that prograde metamorphism dehydration cannot significantly fractionate Ca isotopic compositions of meta-basaltic rocks. Given the comparable CaO contents in meta-basaltic rocks with increasing metamorphism grade, isotope fractionation may be limited by insignificant Ca loss during dehydration. Two heavy greenschists with δ44/42Ca of 0.46‰ and 0.49‰ also have high CO2 concentrations, indicating carbonation alteration that is evidenced by 0.04M HCl leaching experiments. The limited δ44/42Ca variation observed in the other metamorphic samples is most likely inherited from their igneous protoliths. Considering that terrestrial basalts have δ44/42Ca systematically lower than the upper mantle, subduction of mafic lithologies (e.g., oceanic slabs) thus could reflux light Ca isotopes back into the mantle and may create mantle heterogeneity.

Metabolic Calcium Balance in Rats with Chronic Renal Failure Assessed Using 42Ca Tracer

Objective: This study's objective is to explore the effect of venous calcium (Ca) load on Ca metabolism using an isotope tracer in both healthy rats and rats with chronic renal failure (CRF). Materials and Methods: The methods included inducing CRF by feeding rats with food that containing 0.75% adenine. Both the rats in the control and CRF group received an intravenous injection of 100 mg/kg CaCl2 mixed with 0.5 mg/kg 42Ca for over 2 minutes in order to induce hypercalcemia. Blood samples, urine, and feces were collected for Ca kinetics and metabolism testing before and 24 hours after the injection. Results: Peak blood Ca levels were presented at 5 minutes in both groups but returned to baseline levels differently: within 3 hours in the CRF group and 1 hour in the control group. 24-hour hypercalciuria and a higher weight-corrected fecal Ca loss were consistently detected in the CRF rats before and after the injection, along with a decrease in the percent fractional Ca absorption and true fractional calcium absorption compared to the control group. The increased fecal Ca in the CRF rats primarily resulted from changes in decreased absorption rate, which indirectly lead to an increase in endogenous fecal Ca (EFC). Body weightcorrected EFC levels in the CRF group were significantly higher than those in the control group (207.58 ± 107.18 mg/kg/day vs. 62.44 ± 20.49 mg/kg/day). In addition, EFC was 22.6% and 26.02% of the total fecal Ca in the CRF group and the control group. Conclusion: These results may be useful in the evaluation of calcium metabolism and may have important implications for stable isotopes that are widely used in exploring calcification studies in the CRF.

Biochar-induced changes in metal mobility and uptake by perennial plants in a ferralsol of Brazil’s Atlantic forest

Despite an abundance of short-term studies focusing on biochar’s effects on annual plants, the long-term effects of biochar on perennial plants and the effects of the biochar on the mobility and speciation changes of metals/metalloids not limited to main plant nutrients in soils are poorly constrained. This study reports on the amelioration a sloped orthic ferralsol by biochar from Tibouchina wood and the resulting effects on perennial crops and microbiota, including a comprehensive analysis of metals/metalloids speciation changes. Fields were amended with biochar and urine-amended biochar (2 kg/m2) and were planted with papaya, banana, and manioc. Soil and plant materials were analyzed using acid digestions, sequential extractions, and 16S rRNA gene sequencing. Biochar applications led to decreased soil acidity, shifted the cation exchange capacity from being Al-influenced to being Mg/K/Ca-dominated, and elevated the concentrations of Mg, K, Ca, Zn, and Ba in soils. The exchangeable/acid-soluble fraction of Ca, P, and S notably increased. The soil microbial biome became more species rich and diverse in the biochar-amended fields. Manioc benefited from biochar applications, demonstrating increased growth, which resulted in generally decreased concentrations of trace elements in most plant parts, however, with an increased total elemental uptake. Urine amendment contributed to higher concentrations of P, S, and K in soils, but did not further increase plant growth. Biochar was shown to be a promising soil amendment for agricultural use of orthic ferralsols of the Brazil’s Atlantic forest region, but the accumulation of potentially harmful metals needs to be considered.

Geochemical and sedimentological characteristics of surface sediments from Ashtamudi Estuary, Southern India: implications for provenance and modern sedimentary dynamics

Geochemical and end-member mixing analyses (EMMA) of the grain-size distribution were conducted on recent surface sediments from Ashtamudi Estuary, Southern India to investigate the hydrodynamic factors that influence the depositional processes in the region. The complex interplay between the natural (fluvial and marine) and anthropogenic influences on the Ashtamudi Estuary have been delineated based on the inter-relationships between geochemical elements and the end members (EM) derived from the grain-size parameters. Si, Al and Fe are the major elements in the sediment of Ashtamudi Estuary constituting 26–47%, 9–21%, and 8–14%, respectively. Four grain-size end members were identified with dominant modes of 7ϕ (EM1), 6ϕ (EM2), 4.5ϕ (EM3), and 3.3ϕ (EM4) corresponding to fine silt, medium silt, coarse silt, and fine sand, respectively. The high contributions of Al, Fe, Cr and Ni combined with the EM1 and EM2 in the upstream of the estuary indicated that the fine-grained sediments were derived from the fluvial inputs into the basin. The marine/tidal influenced lower estuary is characterised by high concentrations of Si, Ti, Ca, Sr and coarse fraction end member (EM3). The elemental concentration of Cu, Zn and Co along with EM4 shows higher values along the shore region suggesting human interventions in the basin. This integrated geochemical analysis and EMMA provide advancement in the knowledge of the transportation mechanisms and regional sediment dynamics from the estuarine system in Southern India.

Paddy Cultivation Significantly Alters Phosphorus Sorption Characteristics and Loss Risk in a Calcareous Paddy Soil Chronosequence

Core Ideas Phosphorus absorbents in calcareous paddy soils increased with rice cultivation age. Calcium primarily determined P availability in calcareous paddy soils without P inputs. Added P was preferentially retained by Fe or Al oxides. The first few years were the main high‐risk periods for P loss. To reveal the dynamics of phosphate behavior in a calcareous paddy soil chronosequence (after 0, 3, 8, 30, and 70 yr of rice [Oryza sativa L.] cropping), P adsorption–desorption isotherms, chemical fractions, and loss risks were investigated. The contents of P adsorbents (i.e., Fe and Al oxides and Ca salts) in the paddy soils increased with cultivation age, mainly through accelerated primary mineral destruction and weathering in an Alfisol, along with a small portion from irrigation waters. The Langmuir equation gave increasing P adsorption capacities (Qmad) of 520.67, 545.67, 662.78, 860.79, and 834.45 mg kg‐1 for 0, 3, 8, 30, and 70 yr. The Qmad was closely correlated with free Fe and Al oxides, amorphous Al oxides, and HCl‐replaceable Ca contents. The fraction of Ca–P was 52.04 to 63.64% without P inputs, indicating that Ca salts primarily determined P availability. The preferential forms of P retained by paddy soils were in the following order: Ca–P > Al–P > Fe–P > loosely sorbed P. The contents of Olsen‐P in 3‐ and 8‐yr paddy soils were 42.1 and 28.1 mg kg‐1, respectively, much higher than for the two older paddy soils and the upland soil (11.6–24.8 mg kg‐1). The highest degree of P saturation and equilibrium P concentration were in the two younger paddy soils, indicating the increasing potential environmental risk of P loss in paddy soils in the first few years. Hence, more attention should be given to P loss in newly reclaimed paddy soils.

Air Pollution, Clustering of Particulate Matter Components and Breast Cancer

Abstract To evaluate the relationship between air pollution, particulate matter (PM) components and breast cancer risk in a U.S.-wide prospective cohort. Methods. We estimated annual average ambient outdoor residential levels of PM2.5, PM10 and NO2 using a land- use regression model for 49,533 Sister Study participants (breast cancer-free women with a sister with breast cancer) living in the contiguous U.S. Predictive k-means was used to assign participants to clusters defined by PM2.5 components profile to evaluate the impact of heterogeneity in the air pollution mixture. Participants were also separately clustered by geographic region, without regard to air pollution mixture. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for invasive breast cancer risk associated with an interquartile range (IQR) increase in pollutants (PM2.5: 3.6 μg/m3, PM10: 5.8 μg/m3, NO2: 5.8 parts per billion (ppb)). For PM2.5, the association was stratified by component cluster membership. Results. During follow-up (mean = 8.4 years), 2,349 invasive cases were identified. There was little to no increase in risk for invasive breast cancer overall in relation to these air pollutants. However, we observed a higher risk of invasive breast cancer associated with an IQR increase in PM2.5 (HR IQR = 1.15, 95% CI 1.03–1.28), PM10 (HRIQR = 1.05, 95% CI 0.99–1.11) and NO2 (HRIQR = 1.10, 95% CI 1.10–1.21) for women in the Western U.S. Associations also varied by clusters derived from PM2.5 component profiles. PM2.5 was associated with a 28% higher risk of invasive breast cancer (95% CI: 1.00–1.64) in a California-based cluster characterized by low sulfur fractions and high fractions of sodium and nitrate. An elevated, although less precise, risk was observed for another Western U.S. cluster (HR = 1.63, 95% CI: 0.92–2.88), characterized by high fractions of Si, Ca, K and Al. Conclusions. Air pollution measures were related to invasive breast cancer for certain subgroups of women, defined by geographic region and PM component profiles. Particulate matter (PM) is a complex mixture and consideration of geographic variability and mixture components may impact observed associations with breast cancer.

Determination of total concentration and bioaccessible fraction of metals in infant cereals by MIP OES

The present study provides information about the total concentration and bioaccessible fraction of metals Al, Ba, Bi, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Pb, Ti and Zn in nine different infant cereal samples. An in vitro digestion method was employed to evaluate the bioaccessibility. The determinations were performed by microwave induced plasma optical emission spectrometry (MIP OES). The bioaccessibility varied according to the type of infant cereal sample. The values of bioaccessible fraction (minimum and maximum) for Cu, Fe, Mn, Pb and Zn were 24–68, 1–10, 7–58, 24–100 and 1–7% of the total concentration, respectively. Al and Ti presented bioaccessibility in only two samples: 6% in the multicereal A and 14% in the rice and oat cereal B, respectively. The concentration of Ba, Bi, Cd, and Cr was below the limit of detection for the bioaccessibility method. The obtained concentrations were lower than the daily recommended intake for essential and toxic elements, with exception of Pb in the rice and oat A sample.

Seasonal dynamics of N:P ratio stoichiometry and Ca fraction for four dominant plants in the Alxa Desert

Seasonal dynamics of N:P ratio stoichiometry and Ca fraction for four dominant plants in the Alxa Desert

Calcium signals between the ryanodine receptor- and mitochondria critically regulate the effects of arsenite on mitochondrial superoxide formation and on the ensuing survival vs apoptotic signaling

A low concentration of arsenite (6 h), selectively stimulating the intraluminal crosstalk between the inositol-1, 4, 5-triphosphate receptor and the ryanodine receptor (RyR), increased the mitochondrial transport of RyR-derived Ca2+ through the mitochondrial Ca2+ uniporter. This event was characterized in intact and permeabilized cells, and was shown to be critical for mitochondrial superoxide (mitoO2.-) formation. Inhibition of mitochondrial Ca2+ accumulation therefore prevented the effects of arsenite, in both the mitochondrial (e.g., cardiolipin oxidation) and extramitochondrial (e.g., DNA single- strand breakage) compartments, and suppressed the Nrf2/GSH survival signaling. The effects of arsenite on Ca2+ homeostasis and mitoO2.- formation were reversible, as determined after an additional 10 h incubation in fresh culture medium and by measuring long-term viability. A 16 h continuous exposure to arsenite instead produced a sustained increase in the cytosolic and mitochondrial Ca2+ concentrations, a further increased mitoO2.- formation and mitochondrial permeability transition. These events, followed by delayed apoptosis (48 h), were sensitive to treatments/manipulations preventing mitochondrial Ca2+ accumulation. Interestingly, cells remained viable under conditions in which the deregulated Ca2+ homeostasis was not accompanied by mitoO2.-formation.In conclusion, we report that the fraction of Ca2+ taken up by the mitochondria in response to arsenite derives from the RyR. Mitochondrial Ca2+ appears critical for mitoO2.- formation and for the triggering of both the cytoprotective and apoptotic signaling. The effects of arsenite were reversible, whereas its prolonged exposure caused a sustained increase in mitochondrial Ca2+ and mitoO2.- formation, and the prevalence of the apoptotic vs survival signaling.

Innovative reference material for improving the quality control in the sucroenergetic sector

Analytical techniques in the sucroenergetic sector can now for the first time be supported by an innovative matrix-matching reference material produced from sugarcane leaves. This will further enhance the validity of the measurement results and contribute significantly to the quality assurance of plant nutrition analysis. The candidate reference material obtained had a low residual moisture and appropriate particle size. Neutron activation analysis was used to determine the mass fraction of Al, Br, Ca, Cl, Ce, Co, Cs, Cu, Fe, Hf, K, La, Mg, Mn, Mo, Na, P, Rb, Sb, Sc, Sm, Sr, Th, V and Zn, and the Kjeldahl method for N. Statistical techniques were applied to evaluate minimum sample mass and within-bottle homogeneity (ANOVA, Tukey test and PCA) and between-bottles homogeneity (ANOVA). It is demonstrated in this paper that the material is homogeneous using 50 mg mass sample for most chemical elements. However, sample masses of 200 mg or greater are required for Co, Na, Sb and V.

Variations in cropland soil organic carbon fractions in the black soil region of China

The use of three discrete soil organic carbon (SOC) pools proposed by the CENTURY model to study the SOC dynamics helps to understand the changes in cropland SOC pool and its stability. This study focuses on a typical black soil (mollisol) region in Northeast China. Based on historical soil data from samples that were collected in the 1980s, we selected 44 sampling points and collected 88 soil samples from the surface (0–20 cm) and subsurface (20–40 cm) layers in 2010. A 100-day laboratory incubation for each sample was conducted to measure the decomposition rates of SOC at different times, and data from the incubation experiment were fitted to a three-pool first-order model that divided the total SOC into active (Ca), slow (Cs) and resistant (Cr) SOC fractions. A method for predicting the concentrations of the three SOC fractions was developed and used to obtain the concentrations of SOC fractions in the 1980s at each sampling point. The results showed that a power function model (Dsoct = a × tb) could be used as the universal SOC decomposition curve model. Using the universal model, the predictive method accurately estimated the concentrations of Ca, Cs and Cr of upland soils in this black soil region, which effectively solved the problem of a lack of soil samples and SOC fractions data in previous studies of the spatial-temporal variations of SOC fractions in regional soils. From 1980 to 2010, the estimated variations of the Ca, Cs and Cr in the surface upland soil were +0.37, −5.53 and −6.32 g kg−1, and the corresponding contributions to the loss of the total SOC were -3.2%, +48.2% and +55.1%, respectively, while the variations of the Ca, Cs and Cr in the subsurface soil were +0.19, −0.43 and −2.45 g kg−1, and the corresponding contributions to the loss of the total SOC were −7.1%, +16.0% and +91.1%, respectively. The decrease in the total SOC is primarily attributed to the decrease of the Cs and Cr fractions in the region, although the Ca fraction has significantly increased. The overall variations in the SOC fractions suggest a declining stability of the SOC pool in the black soil region of Northeast China.

In vitro α-amylase and pancreatic lipase inhibitory activity of Cornus mas L. and Cornus alba L. fruit extracts

Less-common fruits from Cornus spp. (Cornaceae), also named dogwoods, have shown antidiabetic, antibacterial and anti-allergic properties and are thus considered a source of phytochemicals that are beneficial to human health. The study aimed to compare the chemical compositions of the aqueous and ethanolic extracts of lyophilized fresh-picked and commercially available dried fruits of Cornus mas (Cm, cornelian cherry) and Cornus alba (Ca) fruits using HPLC-DAD-MS/MS method. Simultaneously, the α-amylase and pancreatic lipase (PL) inhibitory activities of the prepared extracts were compared by in vitro fluorescence assay based on the kinetic hydrolysis of starch or oleate ester of 4-methylumbelliferone (MUO), respectively. Additionally, a bio-assay guided identification of compounds potentially responsible for the inhibition of pancreatic enzymes was performed. Iridoids (loganic acid, cornuside) and anthocyanins (pelargonidin 3-O-galactoside) were identified in the Cm fruit extracts. Flavonoids, such as quercetin and kaempferol derivatives, were detected in the Ca fruit extracts. The chromatographic separation of the constituents of Ca fruit provided a fraction containing phenolic acids derivatives, which inhibited PL activity by 69.9 ± 4.5% at a concentration of 7.5 μg·mL−1. The IC50 of hydroxytyrosol glucoside, isolated from the most active Ca fraction, was 0.99 ± 0.10 mg·mL−1 indicating other constituents responsible for the fraction activity. The most active subfraction from Cm fruit (7.5 μg·mL−1), which inhibited PL activity by 28.3 ± 1.5%, contained pelargonidin 3-O-galactoside. Loganic acid and cornuside in highly pure form did not inhibit lipase activity. The phytochemical constituents of Cm, and particularly of Ca fruit extracts, can inhibit pancreatic enzymes and thus might be considered effective preparations in the prevention and control of hyperlipidemia related diseases.

Experimental investigation on the carbonation properties of dune sand ceramic waste mortar

PurposeThis paper aims to analyse the behaviour of dune sand mortars with the addition of ceramic waste. The objective of improving the performance of these modified mortars was evaluated in terms of accelerated carbonation performance.Design/methodology/approachThe effect of these recycled materials was studied in an experimental programme through several tests. The carbonation depth was determined using a classical phenolphthalein test. The mass fractions of Ca(OH)2 and CaCO3 were calculated using thermogravimetric analysis, water absorption occurring through capillary action and open porosity, and the mechanical characteristics were measured after subjecting the materials to wetting–drying cycles.FindingsThe results show that using ceramic waste provides better performance in terms of water absorption by capillary action, open porosity and carbonation penetration.Originality/valueThis research is a study of the incorporation of ceramic waste up to 10 per cent in dune sand mortar. The choice of using ceramic waste to produce dune sand mortars has benefits from economic, environmental and technical points of view and offers a possibility for improving the durability of mortars.