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The specific source of ancient sedimentary manganese (Mn) deposits is commonly complex. Here we use systematic major and trace element data with strontium (Sr) and neodymium (Nd) isotopic analyses of the Ortokarnash Mn(II) carbonate ores and associated carbonate rocks from the Upper Carboniferous Kalaatehe Formation (ca. 320 Ma) in order to constrain the Mn source. This formation consists of three members: the first member is a volcanic breccia limestone, the second member is a sandy limestone, and the third member is a black marlstone with the Mn(II) carbonate interlayers. Petrographic observations in combination with low Al2O3 (2O3 and 87Sr/86Sr ratios as well as εNd(t) values demonstrate a negligible influence of terrigenous detrital contamination on both Sr and Nd isotopic compositions of the Mn(II) carbonate ores. The Sr isotopes of Mn(II) carbonate ores are most likely affected by post-depositional alteration, while Nd isotopes remain unaltered. The initial 87Sr/86Sr ratios in the associated carbonate rocks are likely the result of a mixture of the chemical components (i.e., seawater) and the Al-rich components (e.g., volcanoclastic material), while the detrital effects on Nd isotopes are negligible. In addition, both Sr and Nd isotopes in these non-mineralized wall rocks remained unchanged during post-depositional processes. The relatively low Th/Sc ratios and positive εNd(t) values suggest that the aluminosilicate fraction in the calcarenite and sandy limestone was mainly derived from the weathering of a depleted mafic source, representing the riverine input into the seawater. Given that the Mn(II) carbonate ores are characterized by negative εNd(t) values, these suggest that seafloor-vented hydrothermal fluids derived from interaction with the underlying old continental crust mainly contribute to the source of the Mn(II) carbonates.

Matrix solid phase dispersion (MSPD) is a rapid and flexible sample pretreatment method that accomplishes sample disruption, extraction, filtering and purification in one step and is especially suitable for solid, semisolid and viscous samples. More than 30 years have elapsed since it was first proposed, and there are many published reviews. However, there is no review on the use of MSPD to extract active compounds from natural products. In this review, the latest developments from 2015–2021 in MSPD microextraction techniques, including sorbents, elution solvents and assisted MSPD extraction, along with their applications in natural products, are systematically discussed and classified according to the structure of the active constituents, which mainly refer to phenolic acids, flavonoids, alkaloids, anthraquinones and terpenes. [ABSTRACT FROM AUTHOR]

A novel, green and efficient in-situ cloud point-reinforced ionic liquid-assisted mechanochemical extraction (IS-CPR-IL-MCE) technique coupled with ultrahigh performance liquid chromatography was established to simultaneously extract, concentrate and separate five alkaloids (including liensinine, isoliensinine, neferine, O-demethyl nuciferine and nuciferine) from lotus leaf. The parameters affecting the extraction efficiency of target analytes, such as the amount of IL, surfactant and salt, grinding time, pH, enrichment temperature and time were systematically studied and optimized by single-factor and multifactor experiments. The highest extraction yield of alkaloids was obtained by IS-CPR-IL-MCE under the following conditions: 0.23 g of 1-dodecyl-3-methylimidazolium bromide, 0.37 g of Triton X-100, 7.73 of pH, 5 min of milling time, 2.5 g of (NH 4) 2 SO 4 , 60 ℃ and 20 min of enrichment temperature and time. The developed method exhibited a good linearity in the range of 0.5–100.0 μg/mL with the coefficients of correction more than 0.9992, low limit of detection of 8.0–11.2 ng/mL, acceptable reproducibility below 4.45%, and satisfactory recovery in the range of 80.4–93.7% The results demonstrated that the proposed method was successfully applied to the extraction of alkaloids from lotus leaf. • An ionic liquid assisted mechanochemical extraction was developed. • This method was reinforced by in-situ cloud point extraction. • This method was suitable for simultaneous extraction and enrichment of alkaloids. • Environmental protection, efficient extraction and good repeatability were achieved. [ABSTRACT FROM AUTHOR]

• An in situ effervescence reaction-assisted MCAE method is proposed. • Ganoderma lucidum samples are mechanically ground with solid acid-base reagents. • Ganoderic acids are extracted by water instead of an organic solvent. • The approach has the advantages of simple operation and high efficiency. The aim of this work was to develop a simple, green and low-consumption method for the extraction of ganoderic acids. An in situ effervescence reaction-assisted mechanochemical extraction method was proposed, and the effects of independent variations in terms of sodium bicarbonate concentration, milling time, and liquid/solid ratio (mL/g) were investigated by means of a response surface methodology (RSM) Box-Behnken design (BBD). The highest yields of ganoderic acids were achieved by grinding a Ganoderma lucidum sample with sodium bicarbonate (372.60 mg/g) and citric acid for 0.87 min with a water to material ratio of 10.58 mL. The linear calibration ranges were from 0.01–5 μg/mL for the six analytes and had good linearity with a correlation coefficient of determination higher than 0.9991. In addition, the obtained LODs of the six target analytes were 1.46 − 2.97 ng/mL, and the LOQs calculated as ten times the signal-to-noise ratio were 4.88 − 9.90 ng/mL. The proposed method was successfully applied to the Ganoderma lucidum samples. [ABSTRACT FROM AUTHOR]