One-pot fabrication of magnetic fluorinated carbon nanotubes adsorbent for efficient extraction of perfluoroalkyl carboxylic acids and perfluoroalkyl sulfonic acids in environmental water samples

Abstract(#br)Efficient extraction of perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs) is challenging due to their highly fluorinated property. Based on the particular characters of PFCAs and PFSAs, a new type of magnetic fluorinated carbon nanotubes adsorbent (MFCA) for magnetic solid phase extraction (MSPE) was fabricated facilely using one-pot hydrothermal approach. The morphology, structure and magnetic properties of the prepared MFCA were investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometry. It was observed that the resultant adsorbent possessed satisfactory superparamagnetism and saturation magnetism. Furthermore, the MFCA exhibited excellent enrichment performance for target PFCAs and PFSAs by means of fluorous-fluorous, hydrophobic and hydrogen bonding interactions. Under the most favorable preparation and extraction conditions, the proposed MFCA/MSPE was combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to quantify ultra trace target analytes in environmental water samples. The limits of detection (S/N = 3) of PFCAs and PFSAs were 0.010–0.036 ng/L and 0.024–0.50 ng/L, respectively. In addition, the introduced approach also displayed other features such as quick extraction procedure, wide linear dynamic ranges, excellent method precision and eco-friendliness. Finally, the concentrations of PFCAs and PFSAs in tap, river, lake and waste water samples were successfully measured by isotope internal standard calibration curve method

Establishment and Application of Real-time PCR Detection Method for Lactobacillus kefiranofaciens subsp. kefiranofaciens

This study developed a real-time polymerase chain reaction (real-time PCR) method for the detection of Lactobacillus kefiranofaciens subsp. kefiranofaciens. Based on the 16S rDNA gene sequence and whole genome sequence of the type strain of L. kefiranofaciens subsp. kefiranofaciens ZW3, specific primers were designed and screened. The fluorescent dye SYBR Green I was used in the real-time PCR method. Its specificity, sensitivity and repeatability were evaluated, and this method was applied to detect several strains of this species and its mixtures with other lactic acid bacteria. The results showed that the proposed method was highly specific, sensitive and repeatable. The standard curve was linear with a determination coefficient (R2) of 0.965. Moreover, this method could specifically detect L. kefiranofaciens subsp. kefiranofaciens from its mixture with other lactic acid bacteria. In summary, the real-time PCR method could quickly and accurately detect L. kefiranofaciens subsp. kefiranofaciens, providing a new method for the specific qualitative and quantitative detection of L. kefiranofaciens subsp. kefiranofaciens

基于多相互作用的整体纤维固相微萃取技术用于水和植物样品中全氟烷基膦酸的灵敏测定。

Due to highly fluorinated and di-anionic characters, it is great challenging to enrich perfluoroalkyl phosphonic acids (PFPAs). According to the unique chemical properties and molecular structure of PFPAs, a monolithic adsorbent using dodecafluoroheptyl acrylate and 4-vinylbenzyltrimethylammonium chloride as mixed functional monomers was synthesized and utilized as the extraction medium of multiple monolithic fibers solid-phase microextraction (MMF-SPME). Results well evidenced that the obtained adsorbent could enrich PFPAs effectively by means of multiple interactions including fluorophilic and anion-exchange interactions. Under the optimized synthesized and extraction conditions, a sensitive approach for the monitoring of trace levels of PFPAs in water and vegetable samples was developed by the combination of MMF-SPME and high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Limits of detection (LODs, S/N = 3) for water and vegetable samples were in the ranges of 0.00011-0.00086 μg/L and 0.0022-0.055 μg/kg, respectively. The introduced method was successfully applied to monitor target PFPAs in lake water, wastewater, pumpkin and cucumber samples. Recoveries at different spiking levels and the relative standard deviations for precision were in the ranges of 80.6-120% and 0.9-12%, respectively. Compared to previously reported approaches, the current method displays some merits such as simple operation, satisfactory sensitivity, low cost and eco-friendliness

Inhibitory effects of pine nodule extract and its component, SJ-2, on acetylcholine-induced catecholamine secretion and synthesis in bovine adrenal medullary cells

Extract of pine nodules (matsufushi) formed by bark proliferation on the surface of trees of Pinus tabulaeformis or Pinus massoniana has been used as an analgesic for joint pain, rheumatism, neuralgia, dysmenorrhea and other complaints in Chinese traditional medicine. Here we report the effects of matsufushi extract and its components on catecholamine secretion and synthesis in cultured bovine adrenal medullary cells. We found that matsufushi extract (0.0003–0.005%) and its component, SJ-2 (5-hydroxy-3-methoxy-trans-stilbene) (0.3–100 μM), but not the other three, concentration-dependently inhibited catecholamine secretion induced by acetylcholine, a physiological secretagogue. Matsufushi extract (0.0003–0.005%) and SJ-2 (0.3–100 μM) also inhibited ^Ca^ influx induced by acetylcholine in a concentration-dependent manner, similar to its effect on catecholamine secretion. They also suppressed 14C-catecholamine synthesis and tyrosine hydroxylase activity induced by acetylcholine. In Xenopus oocytes expressing α3β4 nicotinic acetylcholine receptors, matsufushi extract (0.00003–0.001%) and SJ-2 (1–100 μM) directly inhibited the current evoked by acetylcholine. The present findings suggest that SJ-2, as well as matsufushi extract, inhibits acetylcholine-induced catecholamine secretion and synthesis by suppression of nicotinic acetylcholine receptor-ion channels in bovine adrenal medullary cells

Recent progress and ongoing challenges in Rhizoma atractylodis research: biogeography, biosynthesis, quality formation and control

Rhizoma atractylodis, including Atractylodes lancea and Atractylodes chinensis, is widely utilized worldwide as a Chinese meteria medica (CMM) due to its rich content of various sesquiterpenoids and other medicinal components. Benefiting from the rapid and ongoing advancements in analytical technologies, significant strides have been achieved in advancing the analysis of Rhizoma atractylodis towards a more systematic, comprehensive, personalized, and intelligent approach. In this review, we highlight the progress made in the biogeography, biosynthesis, quality formation, and control of Rhizoma atractylodis over the past decade. Special attention is given to the incorporation of advanced genetics tools, modern omics technology, and chemometric methods that facilitate the accurate utilization of Rhizoma atractylodis. The elucidation of biosynthetic pathways, the formation of quality, and the control of active components continue to pose challenges in the study of Rhizoma atractylodis. Additionally, this review presents novel directions and opportunities aimed at enhancing ongoing research efforts

Types and characteristics of carbonate reservoirs and their implication on hydrocarbon exploration: A case study from the eastern Tarim Basin, NW China

Carbonate rocks are deposited in the Ordovician, Cambrian, and Sinian of eastern Tarim Basin with a cumulative maximum thickness exceeding 2000 m. They are the main carriers of oil and gas, and a great deal of natural gas has been found there in the past five years. Based on lithofacies and reservoir differences, natural gas exploration domains of eastern Tarim Basin can be classified into five types: Ordovician platform limestone; Ordovician platform dolomite; Cambrian platform margin mound shoal; Cambrian slope gravity flow deposits, and; Sinian dolomite. Carbonate reservoir characteristics of all the types were synthetically analyzed through observation on drilling core and thin sections, porosity and permeability measurement, and logging data of over 10 drilling wells. We find distribution of part of good fracture and cave reservoir in carbonate platform limestone of Ordovician. In the Ordovician, platform facies dolomite is better than limestone, and in the Cambrian, platform margin mound shoal dolomite has large stacking thickness. Good quality and significantly thick carbonate gravity deposit flow can be found in the Cambrian slope, and effective reservoir has also been found in Sinian dolomite. Commercial gas has been found in the limestone and dolomite of Ordovician in Shunnan and Gucheng areas. Exploration experiences from these two areas are instructive, enabling a deeper understanding of this scene

The Effect of Fulvic Acids Derived from Different Materials on Changing Properties of Albic Black Soil in the Northeast Plain of China

Despite low fertility and content of organic carbon in albic black soil, grains are grown in this type of soil in the northeast plain of China in order to find ways to improve the soil’s fertility and crop production. We carried out pot experiments of maize applied with one of three different treatments of fulvic acids (FA) derived from different parent materials: Plant-derived solid (PDSF), mineral-derived liquid (MDLF), and plant-derived liquid (PDLF) applied at respective rates of 2.5, 5, and 5 g kg−1 as well as a control applied at 0 g kg−1. The results showed that soil organic carbon and light fraction C was greater by 29% to 21% and 38% to 21%, respectively, among the treatments compared to that of the control. Similarly, available N content was significantly greater in the PDLF treatment, and P content was also significantly greater in the PDSF treatment. In contrast, available K and extractable Mg contents were lower, as well as organic–inorganic degree complexes and organic–inorganic composites in the PDSF, MDLF, and PDLF treatments compared with those of the control. Further results showed that MDLF and PDLF Fulvic acids (FA) accelerated plant growth, while PDSF limited plant growth. Our study provides empirical evidence that addition of fulvic acid from MDLF and PDLF had more positive effects on soil properties and plant growth than fulvic acid from PDSF. This investigation suggests that application of fulvic acid in liquid form can improve nutrient availability and affect other important chemical, biological, and physical properties of soils

Relationship between Soybean Protein Isolate and Textural Properties of Texturized Vegetable Protein

To identify the ideal soybean protein isolate for texturized vegetable protein processing, the effect of different soybean protein isolates on texturized vegetable protein composition was studied. Three different types of soybean protein isolates were selected and analyzed for functional properties (water holding capacity (WHC), emulsifying properties, foaming properties), amino acid content, and protein secondary structure. Then, using the same formulation, the soybean protein isolates were extruded to produce texturized vegetable protein, and its textural properties, degree of texturization, microstructure, free sulfhydryl (free SH), and disulfide (S-S) content were determined. Lastly, a correlation analysis was performed to examine the connection between soybean protein isolates and texturized vegetable proteins. After correlation analysis, the soybean protein isolate functional properties that affect the textural properties of the texturized vegetable protein were as follows: the emulsifying property affected the hardness, adhesiveness, springiness, gumminess, and chewiness of the texturized vegetable proteins; and the foaming property affected the gumminess, chewiness, and the degree of texturization of the texturized vegetable proteins. In addition, 16 amino acids including threonine (Thr), methionine (Met), and arginine (Arg) affect texturized vegetable proteins, mainly with respect to adhesiveness, springiness, and free SH. The effects of secondary structure (α-helix, random coil) on texturized vegetable proteins were degree of texturization, resilience, and cohesion, respectively. Therefore, choosing the soybean protein isolate with better emulsifying and foaming properties provides a more suitable approach for processing texturized vegetable protein