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Genes Aug 2019We reported changes in the co-regulated mRNA expression in iron walnut () in response to soil pH treatments and identified mRNAs specific to acidic soil conditions....
We reported changes in the co-regulated mRNA expression in iron walnut () in response to soil pH treatments and identified mRNAs specific to acidic soil conditions. Phenotypic and physiological analyses revealed that iron walnut growth was greater for the pH 4-5 and pH 5-6 treatments than for the pH 3-4 and pH 6-7 treatments. A total of 2768 differentially expressed genes were detected and categorized into 12 clusters by Short Time-series Expression Miner (STEM). The 994 low-expression genes in cluster III and 255 high-expression genes in cluster X were classified as acid-responsive genes on the basis of the relationships between phenotype, physiology, and STEM clustering, and the two gene clusters were analyzed by a maximum likelihood (ML) evolutionary tree with the greatest log likelihood values. No prominent sub-clusters occurred in cluster III, but three occurred in cluster X. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that acid-responsive genes were related primarily to arginine biosynthesis and the arginine/proline metabolism pathway, implying that polyamine accumulation may enhance iron walnut acid stress tolerance. Overall, our results revealed 1249 potentially acid-responsive genes in iron walnut, indicating that its response to acid stress involves different pathways and activated genes.
Topics: Acids; Gene Expression Regulation, Plant; Genes, Plant; Juglans; Polyamines; Soil; Stress, Physiological; Transcriptome
PubMed: 31405132
DOI: 10.3390/genes10080605 -
Molecules (Basel, Switzerland) Oct 2020Chinese herbs are a useful resource bank for natural drug development, and have attracted considerable attention to exploit quorum sensing inhibitors (QSIs). This study...
Chinese herbs are a useful resource bank for natural drug development, and have attracted considerable attention to exploit quorum sensing inhibitors (QSIs). This study was designed to screen QSIs from raw Chinese herb materials. Of the 38 common herbs examined, the ethanol extract of flower had the strongest QSI activity. The flower ethanol extract (CFEE) was purified by HPD600, and the QSI activities were examined in further detail. CFEE inhibited violacein production of 026 in a dose-dependent manner, and inhibit the swarming abilities of K-12 and PAO1. Furthermore, CFEE could inhibited biofilm formation and destroyed mature biofilms of K-12 and PAO1. The composition of CFEE was determined by UPLC-MS/MS to distinguish active QSI compounds, and 21 compounds were identified. In addition to gallic acid and caffeic acid, two organic acids, malic acid and succinic acid, were confirmed for the first time to have autoinducer type 1 QSI activities. Therefore, CFEE is a potential QSI that could be used as a novel antimicrobial agent and should be considered for medicinal development.
Topics: Acids; Bignoniaceae; Biofilms; China; Drugs, Chinese Herbal; Ethanol; Flowers; Humans; Plant Extracts; Quorum Sensing
PubMed: 33076321
DOI: 10.3390/molecules25204727 -
Nutrients Jun 2023Chronic low-grade metabolic acidosis is now a common phenomenon in the Western world. The high dietary intake of sulfur-containing amino acids in the form of processed...
Chronic low-grade metabolic acidosis is now a common phenomenon in the Western world. The high dietary intake of sulfur-containing amino acids in the form of processed meats results in an excessive release of acid in the form of protons and non-metabolizable acidic anions. The kidneys produce increasing amounts of ammonia to excrete this acid. This process requires the breakdown of the nitrogenous amino acid glutamine, which the body provides by breaking down muscle tissue. Hitherto not examined, we hypothesized that a high dietary acid load (DAL) could alter the serum concentrations of selected amino acids. Using secondary data from a 4-week dietary intervention study conducted in 2017, we examined the associations between various amino acids and DAL in = 42 individuals who either consumed a meat-rich or vegan diet. Results from this secondary data analysis suggested that DAL (as measured by the potential renal acid load and net endogenous acid production) is positively correlated with higher serum concentrations of lysine and 1-methyl-histidine (r = 0.50 and 0.43, respectively) and negatively correlated with glutamine and glycine (r = -0.43 and -0.47, respectively). The inverse association with glycine and glutamine warrants special attention, as both play an important role in many metabolic disorders and the immune system.
Topics: Humans; Diet, Vegan; Vegans; Secondary Data Analysis; Glutamine; Diet; Meat; Acids; Acidosis; Glycine
PubMed: 37447267
DOI: 10.3390/nu15132942 -
Nature Communications Jul 2019Nitroaromatics and nitroheteroaromatics serve as key building blocks and intermediates in synthesis, and form the core scaffold of a vast number of materials, dyes,...
Nitroaromatics and nitroheteroaromatics serve as key building blocks and intermediates in synthesis, and form the core scaffold of a vast number of materials, dyes, explosives, agrochemicals and pharmaceuticals. However, their synthesis relies on harsh methodologies involving excess mineral acids, which present a number of critical drawbacks in terms of functional group compatibility and environmental impact. Modern, alternative strategies still suffer from significant limitations in terms of practicality, and a general protocol amenable to the direct C-H functionalization of a broad range of aromatics has remained elusive. Herein we introduce a bench-stable, inexpensive, easy to synthesize and recyclable nitrating reagent based on saccharin. This reagent acts as a controllable source of the nitronium ion, allowing mild and practical nitration of both arenes and heteroarenes displaying an exceptional functional group tolerance.
Topics: Acids; Catalysis; Molecular Structure; Nitro Compounds
PubMed: 31363083
DOI: 10.1038/s41467-019-11419-y -
Proceedings of the National Academy of... Aug 2021Recent research [Wang , 581, 184-189 (2020)] indicates nitric acid (NA) can participate in sulfuric acid (SA)-ammonia (NH) nucleation in the clean and cold upper free...
Recent research [Wang , 581, 184-189 (2020)] indicates nitric acid (NA) can participate in sulfuric acid (SA)-ammonia (NH) nucleation in the clean and cold upper free troposphere, whereas NA exhibits no obvious effects at the boundary layer with relatively high temperatures. Herein, considering that an SA-dimethylamine (DMA) nucleation mechanism was detected in megacities [Yao , 361, 278-281 (2018)], the roles of NA in SA-DMA nucleation are investigated. Different from SA-NH nucleation, we found that NA can enhance SA-DMA-based particle formation rates in the polluted atmospheric boundary layer, such as Beijing in winter, with the enhancement up to 80-fold. Moreover, we found that NA can promote the number concentrations of nucleation clusters (up to 27-fold) and contribute 76% of cluster formation pathways at 280 K. The enhancements on particle formation by NA are critical for particulate pollution in the polluted boundary layer with relatively high NA and DMA concentrations.
Topics: Ammonia; Atmosphere; Dimethylamines; Environmental Pollutants; Environmental Pollution; Models, Chemical; Nitric Acid; Sulfuric Acids; Thermodynamics
PubMed: 34453007
DOI: 10.1073/pnas.2108384118 -
The Journal of Neuroscience : the... Aug 1991Lactic acidosis has been proposed to be one factor promoting cell death following cerebral ischemia. We have previously demonstrated that cultured neurons and glial are... (Comparative Study)
Comparative Study
Lactic acidosis has been proposed to be one factor promoting cell death following cerebral ischemia. We have previously demonstrated that cultured neurons and glial are killed by relatively brief (10 min) exposure to acidic solutions of pH less than 5 (Goldman et al., 1989). In the present series of experiments, we investigated the relationship between changes in intracellular pH (pHi) and cellular viability. pHi was measured using fluorescent pH probes and was manipulated by changing extracellular pH (pHe). Homeostatic mechanisms regulating pHi in neurons and glia were quickly overwhelmed: neither neurons nor glial cells were able to maintain baseline pHi when incubated at pHe below 6.8. Neuronal and glial death was a function of both the degree and the duration of intracellular acidification, such that the LD50 following timed exposure to HCl increased from pH, 3.5 for 10-min acid incubations to pHi 5.9 for 2-hr exposures and pHi 6.5 for 6-hr exposures. Replacement of HCl with lactic acid raised the LD50 to pHi 4.5 for 10-min acid exposures, but did not change the LD50 for longer exposures: pHi measurements concurrent with extracellular acidification suggested that the greater cytotoxicity of lactic acid relative to that of HCl was caused by the more rapid intracellular acidification associated with lactic acid. The onset of death after exposure to moderately acidic solutions was delayed in some cells, such that death of the entire cell population became evident only 48 hr after acid exposure. During this latency period, cellular viability indices and ATP levels fell in parallel.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Acids; Adenosine Triphosphate; Animals; Cell Survival; Cells, Cultured; Coloring Agents; Culture Media; Hydrochloric Acid; Hydrogen-Ion Concentration; Lactates; Lactic Acid; Neuroglia; Neurons; Temperature; Time Factors
PubMed: 1869926
DOI: 10.1523/JNEUROSCI.11-08-02489.1991 -
Chembiochem : a European Journal of... Dec 2016Recent work on triazabutadienes has shown that they have the ability to release aryl diazonium ions under exceptionally mild acidic conditions. There are instances that...
Recent work on triazabutadienes has shown that they have the ability to release aryl diazonium ions under exceptionally mild acidic conditions. There are instances that require that this release be prevented or minimized. Accordingly, a base-labile protection strategy for the triazabutadiene is presented. It affords enhanced synthetic and practical utility of the triazabutadiene. The effects of steric and electronic factors in the rate of removal are discussed, and the triazabutadiene protection is shown to be compatible with the traditional acid-labile protection strategy used in solid phase peptide synthesis.
Topics: Acids; Butadienes; Molecular Structure; Peptides
PubMed: 27662242
DOI: 10.1002/cbic.201600517 -
Journal of Environmental Management Oct 2022Volatile fatty acids, intermediate products of anaerobic digestion, are one of the most promising biobased products. In this study, the effects of acidic (pH 5), neutral...
Volatile fatty acids, intermediate products of anaerobic digestion, are one of the most promising biobased products. In this study, the effects of acidic (pH 5), neutral (without pH adjustment) and alkali (pH 10) pH on production efficiency and composition of volatile fatty acids (VFAs) and bacterial community profile were analyzed. The anaerobic sequencing batch reactors were fed cheese production wastewater as substrate and inoculated by anaerobic granular seed sludge. The results showed that acidic pH improved VFA production yield (0.92 at pH 5; 0.42 at pH 10 and 0.21 gCOD/gVS at neutral pH). Furthermore, propionic acid was dominant under both pH 10 (64 ± 20%) and neutral pH (72 ± 8%), whereas, acetic acid (23 ± 20%4), propionic acid (22 ± 3%), butyric acid (21 ± 4%) and valeric acid (15 ± 8%) were almost equally distributed under pH 5. Adaptation of bacterial community to different pH conditions might steer the acid profile: Bacteroidetes (50.07 ± 2%) under pH 10, Proteobacteria (40.74 ± 7%) under neutral pH and Firmicutes (47.64 ± 9%) under pH 5 were the most dominant phylum, respectively. Results indicated pH plays a significant role in VFA production, acid composition, and bacterial community structure. However, in order to gain a concrete understanding effects of pH, characterization of intracellular and extracellular metabolites with dynamics of the microbial community is required.
Topics: Acids; Anaerobiosis; Bacteria; Bioreactors; Fatty Acids, Volatile; Fermentation; Hydrogen-Ion Concentration; Propionates; Sewage
PubMed: 35982552
DOI: 10.1016/j.jenvman.2022.115700 -
Molecules (Basel, Switzerland) Feb 2022Sixteen organic acids were quantified in peel and pulp of Amber, Laird's Large and Mulligan cultivars of tamarillo using GC-MS. Fourteen of these compounds had not...
Sixteen organic acids were quantified in peel and pulp of Amber, Laird's Large and Mulligan cultivars of tamarillo using GC-MS. Fourteen of these compounds had not previously been quantified in tamarillo. An untargeted metabolomics approach was used in parallel to identify and quantify 64 more metabolites relative to the internal standard, indicating abundances of glutamic acid, pro-line, aspartic acid and γ-aminobutyric acid as well as lower concentrations of several other essential fatty acids and amino acids. The main findings were that total organic acid concentration was significantly higher ( < 0.05) in pulp than in peel, with the highest concentration seen in Mulligan pulp (219.7 mg/g DW). Remarkably, after citric acid, the potent bactericide itaconic acid was the second most abundant organic acid. At least 95% of organic acids in tamarillo were one of these two acids, as well as cis-aconitic, malic and 4-toluic acids. Differences between cultivar chemotypes were as substantial as differences between tissues. These results suggest that the bitter flavour of the peel does not result from organic acids. The combination of targeted and untargeted metabolomics techniques for simultaneous qualitative and quantitative investigation of nutrients and flavours is efficient and informative.
Topics: Acids; Formates; Gas Chromatography-Mass Spectrometry; Metabolome; Metabolomics; Organic Chemicals; Reproducibility of Results; Solanum
PubMed: 35209098
DOI: 10.3390/molecules27041314 -
ChemSusChem Apr 2014Mild fractionation/pretreatment processes are becoming the most preferred choices for biomass processing within the biorefinery framework. To further explore their... (Review)
Review
Mild fractionation/pretreatment processes are becoming the most preferred choices for biomass processing within the biorefinery framework. To further explore their advantages, new developments are needed, especially to increase the extent of the hydrolysis of poly- and oligosaccharides. A possible way forward is the use of solid acid catalysts that may overcome many current drawbacks of other common methods. In this Review, the advantages and limitations of the use of heterogeneous catalysis for the main groups of solid acid catalysts (zeolites, resins, carbon materials, clays, silicas, and other oxides) and their relation to the hydrolysis of model soluble disaccharides and soluble poly- and oligosaccharides are presented and discussed. Special attention is given to the hydrolysis of hemicelluloses and hemicellulose-derived saccharides into monosaccharides, the impact on process performance of potential catalyst poisons originating from biomass and biomass hydrolysates (e.g., proteins, mineral ions, etc.). The data clearly point out the need for studying hemicelluloses in natura rather than in model compound solutions that do not retain the relevant factors influencing process performance. Furthermore, the desirable traits that solid acid catalysts must possess for the efficient hemicellulose hydrolysis are also presented and discussed with regard to the design of new catalysts.
Topics: Acids; Catalysis; Disaccharides; Hydrolysis; Oligosaccharides; Polysaccharides
PubMed: 24616436
DOI: 10.1002/cssc.201300720