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Interactive effects of pH and aluminum on the secretion of organic acid anions by roots and related metabolic factors in Citrus sinensis roots and leaves
2020
Yang, Tao-Yu | Qi, Yi-Ping | Huang, Hui-Yu | Wu, Fenglin | Huang, Wei-Tao | Deng, Chong-Ling | Yang, Lin-Tong | Chen, Li-Song
Low pH and aluminum (Al)-toxicity often coexist in acidic soils. Citrus sinensis seedlings were treated with nutrient solution at a pH of 2.5, 3.0, 3.5 or 4.0 and an Al concentration of 0 or 1 mM for 18 weeks. Thereafter, malate, citrate, isocitrate, acid-metabolizing enzymes, and nonstructural carbohydrates in roots and leaves, and release of malate and citrate from roots were measured. Al concentration in roots and leaves increased under Al-toxicity, but it declined with elevating nutrient solution pH. Al-toxicity increased the levels of glucose, fructose, sucrose and total soluble sugars in leaves and roots at each given pH except for a similar sucrose level at pH 2.5–3.0, but it reduced or did not alter the levels of starch and total nonstructural carbohydrates (TNC) in leaves and roots with the exception that Al improved TNC level in roots at pH 4.0. Levels of nonstructural carbohydrates in roots and leaves rose with reducing pH with a few exceptions with or without Al-toxicity. A potential model for the possible role of root organic acid (OA) metabolism (anions) in C. sinensis Al-tolerance was proposed. With Al-toxicity, the elevated pH upregulated the OA metabolism, and increased the flow of carbon to OA metabolism, and the accumulation of malate and citrate in roots and subsequent release of them, thus reducing root and leaf Al and hence eliminating Al-toxicity. Without Al-toxicity, low pH stimulated the exudation of malate and citrate, an adaptive response of Citrus to low pH. The interactive effects of pH and pH on OA metabolism were different between roots and leaves.
Mostrar más [+] Menos [-]Alleviation of the effect of salinity on growth and yield of strawberry by foliar spray of selenium-nanoparticles
2019
Zahedi, Seyed Morteza | Abdelrahman, Mostafa | Hosseini, Marjan Sadat | Hoveizeh, Narjes Fahadi | Tran, Lam-son Phan
The present study investigated the beneficial role of selenium-nanoparticles (Se-NPs) in mitigating the adverse effects of soil-salinity on growth and yield of strawberry (Fragaria × ananassa Duch.) plants by maneuvering physiological and biochemical mechanisms. The foliar spray of Se-NPs (10 and 20 mg L⁻¹) improved the growth and yield parameters of strawberry plants grown on non-saline and different saline soils (0, 25, 50 and 75 mM NaCl), which was attributed to their ability to protect photosynthetic pigments. Se-NPs-treated strawberry plants exhibited higher levels of key osmolytes, including total soluble carbohydrates and free proline, compared with untreated plants under saline conditions. Foliar application of Se-NPs improved salinity tolerance in strawberry by reducing stress-induced lipid peroxidation and H₂O₂ content through enhancing activities of antioxidant enzymes like superoxide dismutase and peroxidase. Additionally, Se-NPs-treated strawberry plants showed accumulation of indole-3-acetic acid and abscisic acid, the vital stress signaling molecules, which are involved in regulating different morphological, physiological and molecular responses of plants to salinity. Moreover, the enhanced levels of organic acids (e.g., malic, citric and succinic acids) and sugars (e.g., glucose, fructose and sucrose) in the fruits of Se-NPs-treated strawberry plants under saline conditions indicated the positive impacts of Se-NPs on the improvement of fruit quality and nutritional values. Our results collectively demonstrate the definite roles of Se-NPs in management of soil salinity-induced adverse effects on not only strawberry plants but also other crops.
Mostrar más [+] Menos [-]Co-metabolic degradation of refractory dye: A metagenomic and metaproteomic study
2020
Zhang, Qingyun | Xie, Xuehui | Liu, Yanbiao | Zheng, Xiulin | Wang, Yiqin | Cong, Junhao | Yu, Chengzhi | Liu, Na | Sand, Wolfgang | Liu, Jianshe
Fructose was utilized as an additional co-substrate to systematically investigate the molecular mechanism of its boosting effect for the degradation of refractory dye reactive black 5 (RB5) by a natural bacterial flora DDMZ1. A decolorizing rate of 98% was measured for sample YE + FRU(200) (with 3 g/L fructose additionally to yeast extract medium, 10% (v/v) inoculation size of flora DDMZ1, 200 mg/L RB5) after 48 h. This result was 21% and 77%, respectively, higher than those of samples with only yeast extract or only fructose. Fructose was found to significantly stimulated both intracellular and extracellular azoreductase secretion causing enhanced activity. Metagenomic sequencing technology was used to analyze the functional potential of genes. A label-free quantitative proteomic approach further confirmed the encoding of functional proteins by the candidate genes. Subsequently, the molecular mechanism of RB5 degradation by candidate genes and functional proteins of the dominant species were proposed. This study provides important perspectives to the molecular mechanism of co-metabolic degradation of refractory pollutants by a natural bacterial flora.
Mostrar más [+] Menos [-]Effect of ammonia stress on carbon metabolism in tolerant aquatic plant—Myriophyllum aquaticum
2020
Gao, Jingqing | Liu, Lina | Ma, Na | Yang, Jiao | Dong, Zekun | Zhang, Jingshen | Zhang, Jinliang | Cai, Ming
In this study, the tips of Myriophyllum aquaticum (M. aquaticum) plants were planted in open-top plastic bins and treated by simulated wastewater with various ammonium-N concentrations for three weeks. The contents of related carbohydrates and key enzyme activities of carbon metabolism were measured, and the mechanisms of carbon metabolism regulation of the ammonia tolerant plant M. aquaticum under different ammonium-N levels were investigated. The decrease in total nonstructural carbohydrates, soluble sugars, sucrose, fructose, reducing sugar and starch content of M. aquaticum were induced after treatment with ammonium-N during the entire stress process. This finding showed that M. aquaticum consumed a lot of carbohydrates to provide energy during the detoxification process of ammonia nitrogen. Moreover, ammonia-N treatment led to the increase in the activitives of invertase (INV) and sucrose synthase (SS), which contributed to breaking down more sucrose to provide substance and energy for plant cells. Meanwhile, the sucrose phosphate synthase (SPS) activity was also enhanced under stress of high concentrations of ammonium-N, especially on day 21. The result indicated that under high-concentration ammonium-N stress, SPS activity can be significantly stimulated by regulating carbon metabolism of M. aquaticum, thereby accumulating sucrose in the plant body. Taken together, M. aquaticum can regulate the transformation of related carbohydrates in vivo by highly efficient expression of INV, SPS and SS, and effectively regulate the osmotic potential, thereby delaying the toxicity of ammonia nitrogen and improving the resistance to stress. It is very important to study carbon metabolism under ammonia stress to understand the ammonia nitrogen tolerance mechanism of M. aquaticum.
Mostrar más [+] Menos [-]The effect of simulated acid rain on the biochemical composition of Scots pine (Pinus sylvestris L.) needles
1996
Shumejko, P. | Ossipov, V. | Neuvonen, S. (Institute of Forest, Krasnoyarsk, 660036 Akademgorodok (Russian Federation))
Short-time irrigation on young olive tree (Olea europaea L. cv. Chemlali) with untreated industrial poultry wastewater: investigation of growth parameters and leaves chemical composition
2021
The purpose of this study was to evaluate the short-term irrigation effect with industrial poultry wastewater on young olive trees (Olea europaea L. cv. Chemlali). Industrial poultry wastewater can be considered as a bio-fertilizer due to its richness in nutritive elements (SO₄²⁻, HCO₃⁻, total nitrogen, and K⁺). The physicochemical analysis of wastewater showed a high concentration of TSS, COD, BOD, COT, NO₃⁻, and conductivity. Measurements indicated that poultry wastewater enhanced plant growth, leaves dry matter, and ashes in comparison with tap water, as well as poultry wastewater diluted with tap water; however, a decrease in total soluble sugars (glucose and fructose) was detected in leaves. The determination of fatty acid profile of young olive trees leaves irrigated with poultry wastewater showed richness on saturated fatty acids in comparison with mono- and poly-unsaturated ones. In addition, oleic acid (C₁₈:₁) presented the lowest content in leaves of trees irrigated with poultry wastewater irrigation. According to those results, poultry wastewater lends itself to being a hydric alternative and at the same time a source of nutrients that can help fill the water deficit in semi-arid countries and avoid costly waste disposal for slaughterhouses.
Mostrar más [+] Menos [-]Acceleration of Anthraquinone-Type Dye Removal by White-Rot Fungus Under Optimized Environmental Conditions
2012
Hadibarata, Tony | Yusoff, Abdull Rahim Mohd | Kristanti, Risky Ayu
The decolorization of the recalcitrant dye Remazol Brilliant Blue R (RBBR) by the culture filtrate of Polyporus sp. S133 and the effect of various environmental factors were investigated. Both biodegradation and biosorption were playing an important role in bioremoval mechanisms. The highest biosorption of RBBR in Polyporus sp. S133 was shown by all carbon sources such as sucrose, glucose, fructose, and starch. No biosorption was shown by the addition of aromatic compounds and metal ions; 97.1 % RBBR decolorization was achieved in 120-rpm culture for 96 h, as compared to 49.5 % decolorization in stationary culture. Increasing the shaking rotation of the culture to more than 120 rpm was proven to give a negative effect on decolorization. The highest production of laccase was shown at pH 4 and constantly decreases when the pH level increases. The addition of glucose, ammonium tartrate, Cu²⁺, and protocatechuic acid was the suitable environmental condition for RBBR decolorization. There was a positive relationship between all environmental conditions and laccase production in the decolorization of RBBR.
Mostrar más [+] Menos [-]Separation of Cr(VI), acetonitrile, and tetrahydrofuran from water using reducing sugars and HCl
2022
Telepanich, Alicia | Marshall, Tatianna | Marangoni, Alejandro G. | Pensini, Erica
Acetonitrile (AN), tetrahydrofuran (THF), and Cr(VI) are toxic pollutants found in industrial wastewater and groundwater. The reducing sugar fructose separates AN and THF from water, at either neutral or acidic pH (pH = 4), either with or without Cr(VI) (as observed in bottle tests). This is because it preferentially hydrogen bonds water, inhibiting its interactions with AN and THF. When HCl is added to solutions of Cr(VI) and fructose in AN-water or THF-water, it induces Cr(VI) migration from the water to the separated THF- or AN-rich layers. Cr(VI) partitioning in the AN- and THF-rich phases is evident from their discoloration (from transparent to orange). Therefore, when fructose and HCl are used together, they enable the simultaneous removal of Cr(VI) and organic solvents from water. Other acids (e.g., H₂SO₄) enable Cr(VI) migration to AN or THF only in the presence of chloride salts, demonstrating that pH and chloride ions are both responsible for Cr(VI) migration in AN or THF.
Mostrar más [+] Menos [-]Icariin ameliorates metabolic syndrome-induced benign prostatic hyperplasia in rats
2022
Aljehani, Abeer A. | Albadr, Nawal A. | Nasrullah, Mohammed Z. | Neamatallah, Thikryat | Eid, Basma G. | Abdel-Naim, Ashraf B.
Metabolic syndrome (MetS) is an immense health issue that causes serious complications in aging males including BPH. Icariin (ICA) is a flavonol glycoside that exerts a plethora of pharmacological effects. The present investigation tested the potential of ICA to ameliorate benign prostatic hyperplasia (BPH) induced by MetS in rats. Animals were allocated to 5 groups in which the first and second groups were kept on water and regular food pellets. MetS was induced in the third, fourth, and fifth groups by keeping the animals on high fructose and salt diets for twelve consecutive weeks. These groups were given vehicle, ICA (25 mg/kg), and ICA (50 mg/kg), respectively. MetS was confirmed by an increase in rats’ weight, accumulation of visceral fat, insulin resistance, and dyslipidemia. This was accompanied by manifestation of BPH including increased prostate weight, prostate index, and histopathological alterations. Treating the animals with both doses of ICA significantly ameliorated the increase in weight and index of the prostate as well as altered prostate histopathology. In addition, ICA significantly decreased cyclin D1 expression, upregulated Bax, and downregulated Bcl2 mRNA expression. ICA prevented lipid peroxidation, reduced glutathione depletion, and catalase exhaustion, which further lowered markers of prostate inflammation such as interleukin-6 and tumor necrosis factor-α. Moreover, ICA prevented the decrease in prostate content of phosphorylated 5′-adenosine monophosphate (AMP)-activated protein kinase (pAMPK). In conclusion, ICA protects against MetS-induced BPH. This is due to its antiproliferative, proapoptotic, antioxidant, and anti-inflammatory activities as well as the activation of AMPK.
Mostrar más [+] Menos [-]Phosphorus-based metabolic pathway tracers in surface waters
2021
Packa, Vlastimil | Howell, Todd | Bostan, Vadim | Furdui, Vasile I.
Trophic status in surface waters has been mostly monitored by measuring soluble reactive phosphorus (SRP) and total phosphorus (TP). Additional to these common parameters, a two-dimensional ion chromatography mass spectrometry (2D-IC-MS) method was used to simultaneously measure soluble phosphate (Pi), pyrophosphate (PPi), and eleven phosphate-containing metabolites (P-metabolites) in Lake Ontario and its tributaries. From the additional P species, PPi, adenosine 5′-monophosphate (AMP), glucose 6-phosphate (G-P), D-fructose 6-phosphate (F-P), D-fructose 1,6-biphosphate (F-2P), D-ribulose 5-phosphate (R-P), D-ribulose 1,5-bisphosphate (R-2P), and D-(-)-3-phosphoglyceric acid (PGA) were detected and quantified in the lake and river samples. The additional multivariate statistical analysis identified similarities between samples collected at different locations. The presence of R-P, R-2P, and F-2P in Lake Ontario tributaries seems to be mainly related to the Calvin cycle, while the lack of all these three P-metabolites and higher PGA levels than G-P in Toronto Harbour samples seems to be the result of depleted Calvin cycle, pentose phosphate, and glycolysis metabolic pathways.
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