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Scientific development provides opportunities to replace many traditional manual methods to achieve more accurate results and higher efficiency. To scientifically ascertain the geographical origin of coffee, this study develops a method for the rapid determination of 16 inorganic elements in coffee using microwave digestion combined with the ICP-MS internal standard method. Principal component analysis (PCA), Fisher discriminant analysis (FDA), and Partial least squares discriminant analysis (PLS-DA) are employed to analyze 40 coffee samples from three production areas of Pu'er, Baoshan, and Wanning. The results show that the linear correlation coefficients of the 16 elements in this method are above 0.999, the detection limits are in the range of 0.0004–0.63 mg/kg, the RSD of the precision experiments are 4.5 %–13.5 %, the recovery rate of the peak experiment is 86.0 %–96.3 % with the RSD of 1.1 %–8.8 %, and the results of the standard substances are within the range of standard values. Using the discriminant analysis of inorganic elements in coffee (FDA and PLS-DA), coffee origin discrimination was realized, and six key elements (Al, Mn, Fe, Cu, Na, and Ba) are identified as effective discriminatory indexes. Accordingly, a coffee origin discrimination model is established, and the overall accuracy discrimination rate of the discrimination model are all more than 90.0 %, and FDA > PLS-DA. The findings indicated that the method has good accuracy and reliability, is suitable for analyzing and determining multiple elements in sample components as targets, and may have a positive impact on the development of related industries.

Wastewater from processing crustacean shell features ultrahigh chloride content. Bioremediation of the wastewater is challenging due to the high chloride ion content, making it inhospitable for most microorganisms to survive and growth. In this study, mangrove wetland-derived fungi were first tested for their salt tolerance, and the highly tolerant isolates were cultured in shrimp processing wastewater and the chloride concentration was monitored. Notably, the filamentous fungal species Aspergillus piperis could remove over 70% of the chloride in the wastewater within 3 days, with the fastest biomass increase (2.01 times heavier) and chloride removal occurring between day one and two. The chloride ions were sequestered into the fungal cells. The genome of this fungal species contained Cl− conversion enzymes, which may have contributed to the ion removal. The fungal strain was found to be of low virulence in larval models and could serve as a starting point for further considerations in bioremediation of shell processing wastewater, promoting the development of green technology in the shell processing industry.

Herein, ZIF-67-derived Co and N-doped carbon (Co/NC) particle-modified multilayer MXene (MXene@Co/NC) was developed as remarkable electrode material for carbendazim (CBZ) detection. MXene as a substrate provides an excellent conductive framework and plentiful accessibility sites. Co/NC particles embedding in MXene can not only prevent the interlayer stacking of MXene but also contribute a great deal of metal catalytic active sites and finally improve the adsorption and catalytic properties of the composite. Accordingly, the MXene@Co/NC electrode displays excellent electrocatalytic activity toward CBZ oxidation. Experimental parameters such as pH value, accumulation time, MXene@Co/NC modification volume and constituent materials’ mass ratios were optimized. Under optimal conditions, the as-prepared sensor based on MXene@Co/NC holds a broad linearity range from 0.01 μM to 45.0 μM with a low limit of detection (LOD) of 3.3 nM (S/N = 3, S means the detection signal, while N represents the noise of the instrument). Moreover, the proposed sensor displays excellent anti-interference ability, superior reproducibility, excellent stability, and successfully achieves actual applications for CBZ detection in a lettuce sample.

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