Increase In Acid Phosphatase Activity Research Articles

Plant growth promoting endophyte modulates soil ecological characteristics during the enhancement process of cadmium phytoremediation

Endophyte assisted phytoremediation of cadmium (Cd) contaminated soil represents a promising strategy. However, the precise soil ecological regulatory mechanisms by which endophyte enhance the Cd phytoextraction remain unclear. Here, we employed the plant growth promoting endophyte (PGPE) Pseudomonas sp. E3, which has been validated to effectively enhance Cd extraction in Solanum nigrum L., to investigate its regulatory mechanism on soil ecology. The results demonstrated that while PGPE inoculation resulted in minimal alterations to the physicochemical properties of the bulk soil, it led to a notable increase in acid phosphatase activity by 17.86% and urease activity by 24.85% in the rhizosphere soil. This, in turn, significantly raised the available nitrogen and phosphorus contents by 16.93% and 21.27%, respectively, in the rhizosphere soil. Additionally, PGPE inoculation effectively replenished the bioavailable fractions of Fe and Cd, which had been depleted due to root uptake. Importantly, the inoculation specifically augmented the abundance of biomarkers p_Patescibacteria, f_Saccharimonadales, and g_Saccharimonadales in the rhizosphere soil. These biomarkers exhibited a significant positive correlation with the available nutrient and metal element contents. Moreover, the co-occurrence network analysis demonstrated that the inoculation resulted in a simplified bacterial community network, which may have facilitated community synergism by displacing bacteria with a negative association. This regulation appears to occur independently of PGPE colonization. Overall, our findings suggested that PGPE also exerts a regulatory influence on soil ecological features, significantly aiding hyperaccumulators in nutrient acquisition and heavy metal accumulation.

Partitioning the effects of coffee-Urochloa intercropping on soil microbial properties at a centimeter-scale

Conservation farming and crop diversity increase soil health, organic matter content, and soil microbial activity. However, the design and implementation of sustainable practices often lack a detailed understanding of their impacts on microbial communities in soil. Here, we studied the effects of an Arabica coffee (Coffea arabica) – Brachiaria (Urochloa spp.) intercropping system on soil microbial properties by partitioning at the centimeter-scale the topsoil layers. In particular, we collected and analyzed four soil layers in a vertical stratification gradient of 0–2.5 cm (layer 1), 2.5–5.0 cm (layer 2), 5–10 cm (layer 3), and 10–15 cm (layer 4). Soil samples were subjected to chemical analysis, bacterial community profiling, and quantification of microbial enzymatic activity for β-glucosidase and acid-phosphatase, in addition to the quantification of N-fixation and P-solubilization gene abundances. We found that intercropping increased acid-phosphatase activity at layer 1, β-glucosidase activity at layers 2 and 3, and the amount of soil organic matter and total magnesium at layers 2 and 3. Intercropping increased the relative abundance of the N-fixation gene at layer 3 and bacterial diversity at layers 1 and 3. Overall, intercropping significantly changed the soil bacterial community structure and resulted in a more interconnected co-occurrence network (i.e., greater node connectivity, network density, and lower edges average path length). Taken together, this study provides evidence for the positive impact of intercropping in the soil at a centimeter-scale vertical stratification. It corroborates the notion that plant diversity stimulates microbial activity and species interactions in soil.

The physiological effect of polystyrene nanoplastic particles on fish and human fibroblasts

Numerous studies have identified the detrimental effects for the biosphere of large plastic debris, the effect of microplastics (MPs) and nanoplastics (NPs) is less clear. The skin is the first point of contact with NPs, and skin fibroblasts have a vital role in maintaining skin structure and function. Here, a comparative approach is taken using three fibroblast cell lines from the zebrafish (SJD.1), human male newborn (BJ-5ta) and female adult (HDF/TERT164) and their response to polystyrene NP (PS-NPs) exposure is characterized. Cells were exposed to environmentally relevant PS-NP sizes (50, 500 and 1000 nm) and concentrations (0.001 to 10 μg/ml) and their uptake (1000 nm), and effect on cell viability, proliferation, migration, reactive oxygen species (ROS) production, apoptosis, alkaline phosphatase (ALP) and acid phosphatase (AP) determined. All fibroblasts took up PS-NPs, and a relationship between PS-NP particle size and concentration and the inhibition of proliferation and cell migration was identified. The inhibitory effect of PS-NPs on proliferation was more pronounced for human skin fibroblasts. The presence of PS-NPs negatively affected fibroblast migration in a time-, size- and concentration-dependent manner with larger PS-NPs at higher concentrations causing a more significant inhibition of cell migration, with human fibroblasts being the most affected. No major changes were detected in ROS production or apoptosis in NP challenged fibroblasts. While the ALP activity was increased in all fibroblast cell lines, only fish fibroblasts showed a significant increase in AP activity. The heterogeneous response of fibroblasts induced by PS-NPs was clearly revealed by the segregation of HDF, BJ.5ta and SJD.1 fibroblasts in principal component analysis. Our results demonstrate that PS-NP exposure adversely affected cellular processes in a cell-type and dose-specific manner in distinct fibroblast cell lines, emphasizing the need for further exploration of NP interactions with different cell types to better understand potential implications for human health.

Phosphorus deficiency alters root length, acid phosphatase activity, organic acids, and metabolites in root exudates of soybean cultivars.

Phosphorus (P) deficiency alters the root morphological and physiological traits of plants. This study investigates how soybean cultivars with varying low-P tolerance values respond to different P levels in hydroponic culture by assessing alterations in root length, acid phosphatase activity, organic acid exudation, and metabolites in root exudates. Three low-P-tolerant cultivars ('Maetsue,' 'Kurotome,' and 'Fukuyutaka') and three low-P-sensitive cultivars ('Ihhon,' 'Chizuka,' and 'Komuta') were grown under 0 (P0) and 258 μM P (P8) for 7 and 14 days after transplantation (DAT). Low-P-tolerant cultivars increased root length by 31% and 119%, which was lower than the 62% and 144% increases in sensitive cultivars under P0 compared to P8 at 7 and 14 DAT, respectively. Acid phosphatase activity in low-P-tolerant cultivars exceeded that in sensitive cultivars by 5.2-fold and 2.0-fold at 7 and 14 DAT. Root exudates from each cultivar revealed 177 metabolites, with higher organic acid exudation in low-P-tolerant than sensitive cultivars under P0. Low-P-tolerant cultivars increased concentrations of specific metabolites (oxalate, GABA, quinate, citrate, AMP, 4-pyridoxate, and CMP), distinguishing them from low-P-sensitive cultivars under P0. The top five metabolomic pathways (purine metabolism, arginine and proline metabolism, TCA cycle, glyoxylate and dicarboxylate metabolism, alanine, aspartate, and glutamate metabolism) were more pronounced in low-P-tolerant cultivars at 14 DAT. These findings indicate that increasing root length was not an adaptation strategy under P deficiency; instead, tolerant cultivars exhibit enhanced root physiological traits, including increased acid phosphatase activity, organic acid exudation, specific metabolite release, and accelerated metabolic pathways under P deficiency.

Effects of winter grazing and N addition on soil phosphorus fractions in an alpine grassland on the Qinghai-Tibet Plateau

Nutrient cycling in alpine grasslands is susceptible to climate change and anthropogenic activities, which can affect soil phosphorus (P) availability. Despite the crucial role of soil P availability in maintaining stability and productivity of grassland ecosystems, limited research has been conducted on the effects of nitrogen (N) addition and winter grazing on P transformation on the Qinghai-Tibet Plateau. In an 8-year experiment, we applied four different N addition rates (0, 25, 50, and 100 kg urea ha−1 year−1) in combination with winter grazing to investigate the effects of N addition and winter grazing on the soil P fractions. The results reveal that increasing the N addition gradually reduced the resin-Pi and NaOH-Pi contents in the soil by increasing the plant P uptake and promoting the release of carboxylates in the rhizosheath, regardless of grazing. Winter grazing decreased the NaHCO3-Pi and NaOH-Pi contents compared with the no-grazing treatment by increasing the P uptake of the plants. In contrast, neither grazing nor N addition affected the HClconc.-P or residual-P content. In the no-grazing plots, the soil NaHCO3-Po content exhibited a gradual increase in response to N addition, whereas N addition had no discernible effect on the NaOH-Po content. In the grazing plots, the NaHCO3- and NaOH-Po contents gradually decreased with N addition, which was associated with the increased acid phosphatase activity in the rhizosheath and the export of forage. Thus, we conclude that N addition promotes the dissolution of NaOH-Pi to more available inorganic P forms. Under winter grazing conditions only, the transformation of P from inorganic to organic forms gradually decreased with increasing N additions.

Global patterns of soil phosphatase responses to nitrogen and phosphorus fertilization

Hydrolysis of organic phosphorus (P) by soil phosphatases is an important process of P cycling in terrestrial ecosystems, significantly affected by nitrogen (N) and/or P fertilization. However, how soil acid phosphatase (ACP) and alkaline phosphatase (ALP) activities respond to N and/or P fertilization and how these responses vary with climatic regions, ecosystem types, and fertilization management remain unclear. This knowledge gap hinders our ability to assess P cycling and availability from a global perspective. We performed a meta-analysis to evaluate the global patterns of soil ACP and ALP activities in response to N and/or P addition. We also examined how climatic regions (arctic to tropical), ecosystem types (cropland, grassland, and forest), and fertilization management (experiment duration and fertilizer type and application rate) affected changes in soil phosphatases after fertilization. It was shown that N fertilizer resulted in 10.1% ± 2.9% increase in soil ACP activity but a minimal effect on soil ALP activity. In contrast, P fertilizer resulted in 7.7% ± 2.6% decrease in soil ACP activity but a small increase in soil ALP activity. The responses of soil ACP and ALP activities to N and/or P fertilization were largely consistent across climatic regions but varied with ecosystem types and fertilization management, and the effects of ecosystem types and fertilization management were enzyme-dependent. Random forest analysis identified climate (mean annual precipitation and temperature) and change in soil pH as the key factors explaining variations in soil ACP and ALP activities. Therefore, N input and ecosystem types should be explicitly disentangled when assessing terrestrial P cycling.

Nitrogen addition influences fine root growth and mycorrhizal symbiosis formation in trees with contrasting root morphology

Nitrogen (N) addition influences fine root growth and mycorrhizal symbiosis formation, the two dominant strategies for tree nutrient acquisition. Arbuscular mycorrhizae (AM) and ectomycorrhizae (ECM) are the two dominant types of mycorrhizal fungi that form symbioses with the roots of most trees. To reveal the divergent adaptive mechanisms and nutrient acquisition strategies of AM and ECM trees under N addition, we investigated the growth and nutrient acquisition of three dominant tree species in a subtropical forest with contrasting fine roots and mycorrhizal fungi symbioses. Castanopsis hystrix with thin fine roots forms associations with ECM. Michelia macclurei and Phoebe bournei with relatively thick fine roots form associations with AM. N addition facilitates the growth of AM trees more obvious than that of the EMC tree. Acid phosphatase activity was increased to overcome N addition-induced P deficiency. The increase in acid phosphatase activity in the rhizosphere of the ECM tree was greater than in AM trees. N addition decreased fine root length and mycorrhizal fungi colonization in all three tree species. The responses of fine roots and mycorrhizal fungi to N addition were species-specific: fine roots were more sensitive than mycorrhizal fungi for C. hystrix and P. bournei, while the opposite pattern (sensitivity of mycorrhiza > roots) was observed for M. macclurei. The divergent sensitivity of the two dominant nutrient acquisition strategies among tree species may facilitate ecological niche partitioning and inter-specific coexistence under limited nutrient availability.

Microbial inoculants improve nutrients uptake and yield of durum wheat in calcareous soils under drought stress in the Mediterranean region

ABSTRACT Despite some evidence in greenhouse experiments, the benefits of Bacillus subtilis and Trichoderma asperellum on nutrients uptake by plants under field conditions are unknown. This work aims to study the effect of these microbial inoculants on durum wheat nutrition and yield under Mediterranean conditions where soils may lead to micronutrients and phosphorus deficiencies and where drought may promote low use efficiencies of applied fertilizers. To this end, three experiments were performed in two growing seasons. B. subtilis increased the uptake of nitrogen, phosphorus, and manganese relative to other treatments in the experiment carried out in the first growing season involving two experimental sites. The increased phosphorus uptake was attributed to the increased activity of alkaline phosphatase. In this first season, T. asperellum increased acid phosphatase activity without effect on P uptake and decreased the P to Zn molar ratio in grains, thus improving grain quality for human consumption. In the second season, the effects of microbial inoculants were less evident possibly due to favourable environmental conditions for crops (higher water availability) or phosphate fertilization. Results evidenced that B. subtilis can be effective improving the development and nutrient uptake of durum wheat under more stressful conditions, such as drought stress.

Influence of chronic hyperhomocysteinemia on the features of bone metabolism in the case of lipopolysaccharide-induced periodontitis.

Periodontal disease is the second most common oral health problem after dental caries. This increasing prevalence makes it not only a health problem, but also a social issue. The pathogenesis of periodontal disease is associated with a number of adverse exogenous and endogenous factors, including hyperhomocysteinemia (HHcy). This study aimed to determine the features of bone metabolism in rats with lipopolysaccharide (LPS)-induced periodontitis combined with chronic thiolactone HHcy. Forty-eight white, non-linear, mature rats were divided into 4 groups: control (n = 12); LPS‑induced periodontitis (n = 12); chronic thiolactone HHcy (n = 12); and periodontitis combined with HHcy (n = 12). The rats were sacrificed the day after the last LPS injection or the day after the last homocysteine (Hcy) thiolactone administration. Bone metabolism was determined based on the activity of alkaline phosphatase (ALP) and acid phosphatase (AP) in blood serum and periodontal homogenate. A decrease in ALP activity (by 40.1%; р = 0.001) and the mineralization index (MI) (3.5 times; р < 0.001) with an increase in AP activity (2.0 times; р < 0.001) was observed in the periodontal homogenate of rats with LPS‑induced periodontitis. In the case of LPS‑induced periodontitis combined with chronic thiolactone HHcy, more pronounced changes in the activity of phosphatases and in MI were established as compared to rats with LPS‑induced periodontitis only. Chronic thiolactone HHcy enhances disturbances in bone metabolism in LPS‑induced periodontitis. The osteotoxic effect of HHcy is associated with the activation of osteoclastogenesis and enhanced bone resorption. However, further research is required on the subject.

Розвиток запалення в травному тракті щурів після тривалого введення алкоголю

The purpose of the work was to experimentally study the chronic alcohol intoxication on the indicators of inflammation and lipid peroxidation in the gastrointestinal system. Materials and methods. Ethyl alcohol was added to the water for 2-month-old male rats, ranging from 5% to 15% for 108 days. In homogenates of mucous membranes of the gastrointestinal tract and liver, the activity of elastase enzymes, acid phosphatase and the concentration of malonic dialdehyde were determined, in serum – elastase activity and malonic dialdehyde content. Results and discussion. Biochemical research of one of the markers of inflammation (elastase activity) in rats found a probable increase of elastase activity in different parts of the digestive tract after prolonged alcohol consumption, regardless of the sex of the animals. Thus, in the serum of rats after the introduction of ethanol, the activity of elastase increased by 71.7%, in the oral mucosa – by 29.2%, in the gastric mucosa – by 55.5%, in the liver – by 29.0%. In the small and large intestine, the level of this marker of inflammation has changed slightly. The level of elastase activity shows the degree of accumulation of leukocytes in the tissues as a result of the development of the inflammatory process. Acid phosphatase activity in the oral mucosa of rats treated with ethanol increased by 47.4%, in the gastric mucosa – by 30.3%, in the mucous membrane of the small intestine – by 37.4%, in the mucous membrane of the colon – by 40.4%, in the liver – by 112.6%. Activation of acid phosphatase, along with other lysosomal enzymes, is the primary inflammatory response that triggers the production of mediators, which in turn cause secondary tissue alteration in subsequent stages of the inflammatory process. Therefore, the results obtained on the activation of acid phosphatase along with elastase indicate the presence of inflammation in the mucous membranes of the digestive tract, and especially in the liver of rats chronically treated with ethanol. The introduction of alcohol also led to an increase in the concentration of malonic dialdehyde in the mucous membranes: the oral cavity – by 20.3%, the stomach – by 32.3%, the small intestine – by 96.6%, the colon – by 50.2%, in the liver – by 39.4%, in serum – by 33.3%. A significant increase in the level of malonic dialdehyde in the tissues of the digestive tract of rats after long-term intake of ethanol is a sign of activation of lipid peroxidation and intensification of oxidative stress reactions. Conclusion. The results of the study of elastase activity indicate the development of inflammation in the mucous membranes of the gastrointestinal tract, liver and serum of rats under the influence of chronic administration of ethanol. Increased acid phosphatase activity in the tissues of the gastrointestinal tract after prolonged use of ethanol indicates damage to cell membranes, which is a consequence of inflammation. A significant increase in the level of malonic dialdehyde in the mucous membranes of the gastrointestinal tract, liver and serum of rats after chronic ethanol intake is a sign of intensification of oxidative stress reactions

Pathomorphological and histochemical parameters in the internal organs of carp infested Cariophyllaeus brachycollis

Pathomorphological and morphohistochemical changes were performed in the intestine of carp at the location of cysts of Cariophyllaeus brachycollis and other organs that do not have direct contact, primarily such as liver, kidneys, spleen, heart. A pathological autopsy of intensively infected carp with C. brachicollis cystism showed a slightly enlarged clay-yellowish liver; the gallbladder is often overflowing with bile. The kidneys are in most cases flabby and surrounded by a jelly-like mass, the spleen is also partially enlarged, and its edges are rounded, indicating dystrophic changes in these organs. The results of morphohistochemical studies have shown that granular dystrophy is observed in carp cells during cariophilic invasion in liver parenchyma cells. The content of α-amino acids and acid phosphatase activity in dystrophically altered hepatocytes increases significantly. The content of CHIC-positive substances increases in and around the veins and sinusoidal capillaries. These processes coincide with the destruction of individual liver beams. At a karyophilosis in kidneys of carp expansion of distal departments of tortuous tubules and a granular dystrophy is observed. In addition, a decrease in the content of neutral glycoproteins, alkaline phosphatase activity with a simultaneous increase in protein and acid phosphatase activity is observed in the brush border of nephrocytes. The appearance of pyroninophilic cells, decrease in the content of CHIC-positive substances, decrease in alkaline activity and increase in acid phosphatase activity were detected in the renal corpuscle. In the endothelium of blood vessels and capillaries, an increase in protein content, a decrease in alkaline phosphatase activity and an increase in acid phosphatase activity were found. Morphohistochemical studies in the capsule of the carp spleen indicate an increase in such indicators as pyroninophilia, CHIC-positive reaction, the presence of α-amino acids, acid phosphatase activity and decreased alkaline phosphatase activity. At the same time in the walls of blood vessels, there is an increase in the CHIC reaction and α-amino acids, a decrease in alkaline phosphatase, and an increase in acid phosphatase activity. Around the vessels in the reticular tissue of the spleen and between the cells of the pancreas significantly increases the accumulation of reticulocytes with increased acid phosphatase, bright pyroninophilic lymphocytes, and hemosiderocytes with an enhanced CHIC response. Morphohistochemical studies of the heart of fish are accompanied by dilation and overflow of blood cavities and vessels of the heart, small hemorrhages, and locally – pyknosis of muscle cell nuclei and granular dystrophy in the myocardium. At the same time in the endocardium – an increase in the number of lymphocytes and plasma cells with high content of DNA and RNA, as well as a marked increase in α-amino acids in connective tissue elastic fibers and squamous epithelial cells of the atrial and ventricular epicardium, alkaline and acid phosphatase. The amount of CHIC-positive substances is reduced in the striated muscle cells of the myocardium and the walls of the blood vessels of the epicardium. Thus, morphological and histochemical studies indicate profound and local changes in karyophilosis in the intestines of carp. In organs that are not directly related to the invasive onset, moderate histopathological and histochemical changes are observed, indicating a moderate severity of functional impairment.

Rat skin inflammation markers change in response to calcium hydroxyapatite and hyaluronic acid administration

In the research, the level of some markers of skin inflammation in Wistar rats was examined after injection of calcium hydroxyapatite and hyaluronic acid drugs of various concentrations, where the nature, degree, extent of tissue damage and the general condition of the animals in general were close to humans’. Each drug was evaluated according to several indicators (MDA content, activity of neutrophil elastase, acid phosphatase, and catalase) to understand the measure of the adequacy of the body's response to the intensity of the stimulus.&#x0D; A biochemical analysis of the skin of laboratory rats after the injection of the studied drugs showed that the safest drugs contain nonstabilized 4% hyaluronic acid. Either in pure form or in a 1: 1 mixture with calcium hydroxyapatite at a concentration of 55.7%, since in 2 months after their injection in the skin of experimental animals, markers of inflammation (elastase, acid phosphatase and MDA levels), catalase and API activity were found at the normal level.&#x0D; The injection of drugs containing stabilized 2% hyaluronic acid and calcium hydroxyapatite 55.7%, as well as stabilized 2.6% hyaluronic acid and calcium hydroxyapatite at a concentration of 1% caused prolonged LPO activation, increased level of inflammation markers and decreased API.&#x0D; The injection of calcium hydroxyapatite drugs without hyaluronic acid, even at a 1: 1 dilution with saline, also caused prolonged LPO activation, an increased level of inflammation markers and a decreased API, and, in addition, revealed a significant increase in acid phosphatase activity, which is an indicator of the integrity of cell membranes.&#x0D; The obtained results made it possible to analyze the features of the molecular response and regulation of inflammation upon injection of calcium hydroxyapatite and hyaluronic acid drugs of different concentrations, which will help in prescribing of treatment.

The features of metabolism and structural organization of dental system under conditions of experimental insulin resistance

Peculiarities of calcium homeostasis, the activity of energy synthesis enzymes and structural organization of the dental system in rats under conditions of insulin resistance were analyzed. It was found that impaired glucose tolerance is manifested by a decreased mineralizing ability of hard tissues of alveolar processes and teeth, accompanied by a decrease in calcium content in erythrocyte mass and alveolar processes and an increase in acid phosphatase activity in blood serum. In rats with insulin resistance a decrease in the activity of lactate- and succinate dehydrogenase was detected. Degenerative changes were observed in the bone thickness of the dental area of insulin resistant rats, which were accompanied by the development of hypercellularity of the osteogenic layer of periosteum. Reactive changes in the tooth pulp were manifested by a decrease in the area of its loose connective tissue. Hyperplastic changes with the formation of unexpressed acanthotic bands developed in the oral mucosa of experimental animals, the thickness of the basal and granular layers increased against the background of a decrease in the prickle layer of epitheliocytes. In experimental group we observed a decrease in the nuclear cytoplasmic index and an increase in keratin formation in the epithelium. A narrowing of the lumen of capillaries and arterioles of the dental area, hyperplasia of endothelial cells and an increased accumulation of glycoproteins, especially in small arteries, were also detected in experimental group. Thus, altered carbohydrate metabolism leads to the metabolic changes of teeth supporting apparatus and oral mucosa, aggravating the course of insulin resistance with the development of dental system pathology.

Colorimetric determination of acid phosphatase activity and inhibitor screening based on in situ polymerization of aniline catalyzed by gold nanoparticles.

A colorimetric assay for acid phosphatase (ACP) was constructed that isbased on in situ polymerization of aniline catalyzed by gold nanoparticles (AuNPs). Aniline can be polymerized by ammonium persulfate (APS) in acidic condition and form gold-polyaniline core-shell nanoparticles (Au@PANI NPs) in the presence of AuNPs with the assistance of sodium dodecyl sulfate (SDS). AuNPs were also found to accelerate the polymerization process of aniline and thus shorten the reaction time. Upon the introduction of ascorbic acid (AA), the oxidant APS was consumed via the redox reaction. That led to the suppression of the formation of PANI. Consequently, ACP activity can be supervised on the basis of hydrolysis of 2-phospho-L-ascorbic acid trisodium salt (AAP) catalyzed by ACP to release AA. With the increase of ACP activity, the intensity ratio of the absorbance at λ705 nm (A705) and the absorbance at λ530 nm (A530) gradually decreased and the color gradually changed from dark-green to light-green to blue-gray to purple and eventually to pink. This method for ACP determination worked in the range 0.40 to 2.00U·L-1. The detection limit is 0.043U·L-1. The assay was applied to determine ACP in human serum. The recovery ranged from 81.0 to 104.6%. Relative standard deviation was less than 5%. This suits the request forbiological sample analysis. Graphical abstract Schematic presentation of the colorimetric determination of acid phosphatase activity and inhibitor screening based on in situ polymerization of aniline catalyzed by gold nanoparticles. : acid phosphatase (ACP); : gold nanoparticles (AuNPs); : gold-polyaniline core-shell nanoparticles (Au@PANI NPs); ascorbic acid (AA); 2-phospho-L-ascorbic acid trisodium salt (AAP).

Immobilization of cadmium by Burkholderia sp. QY14 through modified microbially induced phosphate precipitation

Microbially induced phosphate precipitation (MIPP) is an advanced bioremediation technology to immobilize heavy metals. An indigenous bacterium QY14 with the function of mineralization isolated from Cd contaminated farmland soil was identified as Burkholderia ambifaria. The minimum inhibitory concentration value for QY14 was 550 mg/L for soluble Cd concentration. This study found that the addition of 10 mM Ca2+ during MIPP process could significantly increase the removal ratio of Cd, and the maximum removal ratio of Cd with 10 mM Ca2+ and without Ca2+ in solution was 99.97% and 76.14%, respectively. The increase of acid phosphatase activity and the formation of precipitate containing calcium caused by 10 mM Ca2+ addition contributed the increase of Cd removal efficiency. The results of SEM-EDS, FTIR and XRD showed that Cd was removed by forming Cd containing hydroxyapatite (Cd-HAP). In addition, the dissolution experiment showed the Cd release ratio of Cd-HAP (0.01‰ at initial pH 3.0 of solution) was lower than Cd-absorbed HAP, indicating that Cd was more likely removed by the formation of Ca10−xCdx(PO4)6(OH)2 solid solution. Our findings revealed MIPP-based bioremediation supplied with 10 mM Ca2+ could increase the Cd removal and could potentially be applied for Cd remediation.

Effect of nitrogen additions on soil pH, phosphorus contents and phosphatase activities in grassland

Phosphorus is a key nutrient for all plant species and a limiting factor for grassland ecosystem function. In recent years, in response to the rapid increase of global nitrogen deposition, soil phosphorus contents and phosphatase activities changed to varying degrees in grassland ecosystems. We conducted a meta-analysis to examine the responses of soil pH, total phosphorus (TP), available phosphorus (AP), as well as activities of alkaline phosphatase (AlP) and acid phosphatase (AcP) in soils to nitrogen addition amount, nitrogen type, experimental duration, and sampling depth. The correlation between soil pH and phosphatase response ratio was investigated. The results showed that nitrogen addition significantly reduced soil pH, TP and AlP activity, while significantly increased AcP activity, but had no significant effect on AP. Soil pH and AlP activity significantly decreased under nitrogen addition >5 g·m-2·a-1, and AcP activity significantly increased under high nitrogen addition (>10 g·m-2·a-1). The contents of TP and AP significantly decreased when nitrogen addition was 5-10 g·m-2·a-1. NH4NO3 treatment significantly reduced soil TP and increased AcP activity, while urea treatment significantly reduced soil pH and AlP activity. Across all nitrogen addition amounts, when the experiment duration was 3 to 10 years, soil TP content and AlP activity were significantly reduced. Soil pH was significantly reduced after three years nitrogen addition, and AcP activitiy was significantly increased after 10 years nitrogen addition. In the 0-10 cm soil layer, the TP content and AlP activity significantly decreased, while the AP content significantly increased. In >10 cm soil layer, the AP content was significantly decreased. The significant negative correlation between soil pH and AcP activity indicated that change in soil pH caused by nitrogen addition may be an important factor for the variation of soil phosphatase activity.

Effects of Dietary Xanthophyll Supplementation on Growth Performance, Body Color, Carotenoids, and Blood Chemistry Indices of Chinese Soft‐Shelled Turtle Pelodiscus sinensis

AbstractA 12‐week experiment was conducted to investigate the effects of diets containing 0 (CD), 40 (X1), 80 (X2), and 120 mg/kg (X3) xanthophyll on the growth, body color, and blood chemistry of the Chinese soft‐shelled turtle Pelodiscus sinensis. Four hundred and eighty turtles with initial weight of 37.90 ± 0.26 g were randomly stocked equally in 12 cement ponds (4.0 × 5.0 × 0.8 m) to form four groups in triplicate. The turtles were fed one of the four diets (crude protein 48%, crude lipid 6%) twice daily, with the feed amount set at 3% of their total body weight. The results indicated that the supplement of 80 mg/kg xanthophyll in the diet had the most significant effect on growth, feed conversion ratio, and amino acid content in muscle tissue. The yellowness of the carapace and the plastron skin increased with higher xanthophyll levels. Moreover, the final yellowness in the plastron skin was higher than the initial yellowness. The carotenoid content in the liver and carapace was significantly enhanced with increasing xanthophyll levels and showed a significant linear correlation with the dietary xanthophyll supplement levels. The liver carotenoid content in the X2 and X3 groups and carapace skin carotenoid content in the X3 group were markedly higher than were those in turtles that were fed the control diet (P &lt; 0.05). Compared with the control diet, adding xanthophyll significantly increased acid phosphatase activity in serum while obviously lowering the alanine aminotransferase activity. The triglyceride and total cholesterol content decreased with increases in xanthophyll. There were no significant differences in the serum superoxide dismutase and glutathione peroxidase activity in animals that received the xanthophyll‐supplemented and control diets. The current study results suggest that the growth performance and skin coloration of Chinese soft‐shelled turtle can be improved by including 80–120 mg/kg xanthophyll in the diet.

The Ca2+ -regulated protein kinase CIPK1 integrates plant responses to phosphate deficiency in Arabidopsis thaliana.

Phosphate (Pi) deficiency severely restricts plant growth and development, as Pi is an essential macronutrient. Calcium (Ca2+ ) is a ubiquitous second messenger in plants; calcineurin B-like proteins (CBL) and CBL-interacting protein kinases (CIPK) are signalling pathways that act as an important Ca2+ signalling network which integrates plants to fine tune the response to stress; however, whether CIPK are involved in Pi deficiency stress remains largely unknown. In this study, we carried out a reverse genetic strategy to screen T-DNA insertion mutants of CIPK isoforms under Pi deficiency in Arabidopsis thaliana. Then Pi content, transcription of phosphate starvation-induced (PSI) genes, acid phosphatase activity and hydrogen peroxide were determined in the wild-type (WT) and cipk1 mutant, respectively. The phenotype of CIPK1 complementation lines was analysed. The cipk1 mutant had a more sensitive phenotype, with lower root elongation and root length, and decreased Pi content compared with the WT under Pi deficiency. Moreover, CIPK1 mutation caused phosphate starvation-induced (PSI) genes to be significantly induced under Pi deficiency. Histological staining demonstrated that the cipk1 mutant had increased acid phosphatase activity and hydrogen peroxide concentration under Pi deficiency. By using the yeast two-hybrid system, we further demonstrated the interaction between CIPK1 and the WRKY transcription factors, WRKY6 and WRKY42. Overall, we demonstrate that CIPK1 is involved in the Pi deficiency signalling pathway in A. thaliana, revealing the important role of Ca2+ in the Pi nutrition signalling pathway, and potentially providing a theoretical foundation for molecular breeding of crops with better Pi utilization efficiency.

Monitoring Soil Enzymes Activity before and after Animal Manure Application

Soil enzymes (urease, invertase, acid and alkaline phosphatase) activity in the rhizosphere of field-grown tomato plants were used to monitor the impact of soil amendments (SA) and SA mixed with biochar on soil microbial activity four months after addition of amendments. The soil treatments were sewage sludge (SS); horse manure (HM); chicken manure (CM); vermicompost (worm castings); commercial inorganic fertilizer; commercial organic fertilizer; and no-mulch (NM) native soil used for comparison purposes. Soil treatments also were mixed with 10% (w/w) biochar to investigate the impact of biochar on soil enzymes activity. The results showed a significant increase in soil urease and invertase activities after incorporation of SA to native soil. Vermicompost and HM were superior in increasing urease and invertase activity four months after their addition to native soil. Alkaline phosphatase activity fluctuated among the soil treatments, revealing some obstruction of its activity. SS amended with biochar increased acid phosphatase activity by 115% four months after SS addition. Other than alkaline phosphatase, organic manure enhanced soil biological activity (microbial biomass and release of enzymes), indicating that the use of manures, rather than inorganic fertilizers, in crop production is an affordable and sustainable agricultural production system.

Functions of Lysosomes in Mammalian Female Reproductive System

The lysosome is the most acidic membrane-bound intracellular organelle. Lysosomal acidity is primarily maintained by vacuolar H+-ATPase (V-ATPase) and counter ion channels. There are >60 hydrolytic enzymes in the lysosome for its fundamental digestive role. Lysosomes also play important roles in endocytosis, exocytosis, autophagy, and cell death. Studies that have implicated roles of lysosomes in the female reproductive system are reviewed here. In the ovary, lysosomes are implicated in the preparation of free cholesterol for steroidogenesis and degradation of regulators of steroidogenesis, regulation of follicular atresia, follicle rupture during ovulation, luteal cell survival, and luteal regression. In the oviduct, lysosomes are involved in endocytosis of both serum and oviductal luminal components. In the uterus during the menstrual/estrous cycle, lysosomes are associated with endometrial secretion, apoptosis, and menstruation. In the uterus during early pregnancy, lysosomes are involved in the temporal and directional changes of endocytosis, uterine epithelial acidification upon embryo implantation initiation, and embryo-maternal mutual communications via extracellular vesicles. In the placenta, lysosomes are implicated in nutrient transport and placental separation from the uterus for parturition. In the mammary gland, lysosomes are important for mammary gland development and involution. These findings suggest/demonstrate functions of lysosomes in multiple processes of female reproduction, from ovulation to ovarian steroidogenesis for pregnancy maintenance, and from essential in utero nurturing of developing embryos/fetuses via embryo/fetal-maternal communications, to optional postpartum nurturing of newborns via lactation. Future studies using genetically or modified animal models and pharmacological approaches will provide novel insights into the functions and mechanisms of lysosomes in the mammalian female reproductive system.