Latest ArticlesWith the increasing attention to food safety and environmental quality, efficient and accurate pollutant detection technology is crucial. Supramolecular solvent microextraction technology, as an emerging sample pretreatment method, has demonstrated unique advantages in the field of food and environmental pollutant detection due to its high efficiency, good selectivity and environmental friendliness. This technology is based on the selective recognition and enrichment ability of specific pollutants by supramolecular solvents (such as nano/micro scale solvents formed by host molecules such as cyclodextrin and crown ether), and achieves rapid separation and concentration of target substances in samples through microextraction operations. As a new type of green solvent, supramolecular solvents have high extraction efficiency, wide polarity range, customizable structure, and both extraction and purification effects, making them widely used in the field of extraction and separation. This review introduced the properties of supramolecular solvents and types of supramolecular solvent microextraction, with a focus on the detailed application of this technology in the detection of food and environmental pollutants, and provided prospects for the work in this field, in order to provide reference for the promotion and application of supramolecular solvent-microextraction technology.
Objective To understand the residue status and exposure levels of 6 kinds of quinolone antibiotics in common freshwater fish and shrimp sold in Beijing. Methods The 90 freshwater fish and shrimp products from 40 supermarkets and farmers’ markets in 9 districts and counties of Beijing were randomly sampled for the determination of 6 kinds of quinolone antibiotics in fish and shrimp meat by liquid chromatography-tandem mass spectrometry. The exposure risk of quinolone antibiotic residues in fish and shrimp to residents of 10 gender/age groups was assessed by the index of food safety (IFS). Results The 4 kinds of quinolone antibiotics were detected in 90 fish and shrimp samples. The detection rate for pefloxacin, ofloxacin, enrofloxacin and ciprofloxacin were 1.11% (1/90), 1.11% (1/90), 26.67% (24/90) and 6.67% (6/90). There were excessive samples of pefloxacin, ofloxacin and enrofloxacin detected, with an exceedance rate of 1.11% (1/90), 1.11% (1/90) and 5.56% (5/90) respectively. Norfloxacin and lomefloxacin were not detected in all samples. The IFS of quinolone antibiotics ranged from 0.040-0.067 in the general-case scenario and from 0.170-0.283 in the worst-case scenario, which was much less than 1. Conclusion The detection of quinolone in freshwater fish and shrimp sold in Beijing is dominated by enrofloxacin and ciprofloxacin, and the health risk of 6 kinds of quinolone antibiotics to human beings is at a safe level in this study, which provides regional data support for the assessment of the quality of aquatic products and the revision of food safety standards.
Objective To evaluate the safety of a composite beverage made from Ganoderma leucocontextum fermented Pu-erh tea compound beverage. Methods Using the Ganoderma leucocontextum fermented Pu-erh tea compound beverage as the study subject, based on preliminary experiments and related research, the dose was set at 10000 mg/(kg·bw). The classical limit method was employed, with healthy ICR mice selected as the experimental model, and the test substance was administered via oral gavage. The experiment strictly adhered to animal ethics and welfare principles, with precise control of environmental conditions including temperature, humidity and light cycles to ensure the accuracy and reliability of the data. Results After administration of the test substance, no signs of toxicity were observed in any of the ICR mice throughout the observation period. Their behavioral activity remained normal, with glossy fur and vigorous spirits. Regular precise measurements of mouse body weight showed no significant abnormalities in growth trends, and no deaths occurred. Statistical analysis revealed that the acute oral toxicity median lethal dose (LD50) values for both male and female ICR mice were greater than 10000 mg/(kg·bw), with 95% confidence intervals also exceeding 10000 mg/(kg·bw). Conclusion Based on international acute toxicity dose classification standards, the Ganoderma leucocontextum fermented Pu-erh tea compound beverage is classified as practically non-toxic. This indicates that under the experimental conditions of this study, the acute oral intake safety of this composite beverage is high, providing critical safety data support for subsequent product development and market promotion.
Objective To compare the resistance differences of 18 kinds of bacterial strains and 2 kinds of biological indicators to chlorine-containing disinfectants, hydrogen peroxide and quaternary ammonium compounds. Methods Strains were selected from food, environment and human sources, including gram-negative bacteria, gram-positive bacteria and spore-forming bacteria (6 kinds of strains per category). Species identification was performed using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) and biochemical assays. The 2 kinds of biological indicators, namely Staphylococcus aureus ATCC6538 and Escherichia coli 8099 were used as reference strains. Bacterial suspensions (2.0×108-10.0×108 CFU/mL) were prepared to test their tolerance to sodium hypochlorite (available chlorine 0.00400%-0.00499%), hydrogen peroxide (7.5%), and benzalkonium bromide (3.996 mg/mL). All bacterial strains were treated with disinfectants for 3 minutes. By calculating the killing log value (KL) of disinfectants against different bacterial strains, the differences in resistance of different species of bacterial strains to 3 kinds of disinfectants were compared. Results The bactericidal efficacy ranked as sodium hypochlorite, hydrogen peroxide, benzalkonium bromide. Different species showed significant variations in resistance to disinfectants. Among 3 categories of bacterial strains (gram-negative bacteria, gram-positive bacteria and spore-forming bacteria), there were strains within each category that exhibit higher resistance to disinfectants than 2 kinds of biological indicators. Conclusion Sodium hypochlorite and hydrogen peroxide exhibit superior bactericidal effects compared to benzalkonium bromide. The resistance to disinfectant of bacteria is species-specific and cannot be predicted solely by gram classification. The screening scope for biological indicators should be expanded based on actual needs.
Objective To assess the dietary exposure risk of mycotoxins for Beijing consumers, based on the mycotoxins contamination data during the cold storage period of Castanea mollissima which harvested in Huairou District, Beijing. Methods Castanea mollissima samples were collected from the 4 highest yielding townships in Huairou District. Samples were stored in a cold storage for 1 year and sampled once a month to determine the content of 21 kinds of fungal toxins. Based on the 2002 Beijing residents’ dietary consumption survey data, point estimation method, probability method and cumulative risk assessment modeling method of multiple fungal toxins were used to evaluate the acute and chronic dietary exposure risks of different genders of consumers. Results The estimated daily intake levels of alternariol and alternariol monomethyl ether in some Castanea mollissima samples were higher than 2.5 ng·kg-1·bw·d-1. The estimated daily intake levels of tentoxin and tenuzonic acid in all samples during the entire storage period did not exceed 1500 ng·kg-1·bw·d-1. The estimated daily intake/tolerable daily intak of nivalenol, fumonisin B1, total fumonisin and zearalenone were all less than 100. The margin of exposure (MOE) was used to analyze the sterigmatocystin, and the result was greater than 10000. The 2 kinds of different chronic effects were analyzed for ochratoxin A. The cumulative risk assessment of mycotoxins in Castanea mollissima samples showed that some samples had MOE below 100 after storage for about 10 months. Conclusion All varieties of Castanea mollissima samples are no significant risk of mycotoxins to consumers after stored for 9 months in cold storage, and consumers can safely eat them. But multiple mycotoxins are detected simultaneously during the late stage of storage, which may pose health risks to humans. In order to clarify these health risks further, more toxicological data is needed.
Objective To establish and evaluate the application of direct mercury analysis for the determination of total mercury in food. Methods A direct mercury analysis method was developed based on catalytic pyrolysis-gold amalgamation atomic absorption spectroscopy. By stepwise optimization of pyrolysis temperatures (150 °C/550 °C for low-concentration ranges and 200 °C/650 °C for high-concentration ranges) and carrier gas flow rates (150-200 mL/min), plant-derived samples (e.g., rice, jujube), animal-derived samples (e.g., snakehead, fish meal), and 14 kinds of food samples were analyzed. The method’s detection limit, accuracy, stability and spike recovery were evaluated to assess its performance and matrix applicability. Results The method established dual linear calibration curves of 0-10 ng and 25-200 ng, with correlation coefficients of 0.9993 and 0.9998, respectively. The limit of detection and limit of quantitation were 0.0002 mg/kg and 0.0005 mg/kg, respectively. Spike recoveries ranged from 90% to 116%, the intra-day and inter-day repeatability relative standard deviation was less than or equal to 6.5% and less than or equal to 7.7%, respectively. The method was systematically validated for complex matrices, including plant-derived, animal-derived, and processed foods, with all results complying with the GB 2762-2022 National food safety standard-Limits of contaminants in foods. Conclusion The proposed method eliminates the need for chemical digestion in sample pretreatment, significantly shortens the analytical time, and prevents mercury volatilization losses. It overcomes the limitations of single-matrix analysis and achieves rapid total mercury detection in diverse complex food matrices, thereby providing an efficient and reliable technical solution for food safety risk monitoring and regulatory compliance.
Objective To explore the pollution characteristics of Pseudomonas aeruginosa in packaged drinking water. Methods The detection of Pseudomonas aeruginosa in packaged drinking water sold in the province and produced by local enterprises during the supervision and sampling of Hunan Province from 2022 to 2024 was analyzed. Results The detection rate of Pseudomonas aeruginosa in 3 years was 8.15%, which significantly decreased to 5.74% in 2024 due to strengthened supervision. Other drinking water (9.44%) and sealed packaging (8.65%) had the highest risk. Summer and autumn (11.34% in the third quarter) and areas such as Changde and Xiangxi (over 15%) were high-risk areas for pollution. Conclusion Focusing on strengthening the prevention and control of bacterial protective films in water sources, optimizing seasonal processes and regulating high-risk areas can effectively reduce the pollution of Pseudomonas aeruginosa, thereby improving the sampling pass rate of packaged drinking water products. The research results provide key data support for the quality and safety of packaged drinking water in Hunan Province. The multiple risk superposition mechanism of “climate process management” revealed has practical guidance significance for the prevention and control of food microorganisms in humid and hot regions of Southern China.
Objective To investigate the effects of high-voltage electric field (HVEF), acidic electrolyzed water (AEW) and their combined treatment on γ-aminobutyric acid (GABA) enrichment in germinating Fagopyrum esculentum. Methods Fagopyrum esculentum seeds were respectively treated with HVEF, AEW, and the combined AEW+HVEF treatment. Morphological indices (100-seed weight, germination rate, shoot length), GABA content, and activities of glutamate decarboxylase (GAD), γ-aminobutyric acid transaminase (GABA-T) and succinic semialdehyde dehydrogenase (SSADH) were measured at different time points during germination (0, 8, 12, 32 and 40 h) to analyze the effects of different treatments on GABA enrichment. Results All treatments increased GABA content in Fagopyrum esculentum, with the combined treatment showing a more significant effect. Under the combined treatment, GABA content in germinating Fagopyrum esculentum reached 198.72 mg/100 g at 24 h of germination, which was 35.6% higher than the control group, and 8.3% and 6.1% higher than the AEW and HVEF single-treatment groups, respectively, demonstrating a significant synergistic effect. The dual regulation of the combined treatment promoted GABA accumulation by activating GAD activity and inhibiting GABA-T and SSADH activities. Conclusion This study analyzes the changes in enzyme activities of the GABA metabolic pathway during Fagopyrum esculentum germination, revealing that the combined treatment of HVEF and AEW achieves efficient GABA enrichment through a dual mechanism of “activating synthesis enzymes and inhibiting decomposition enzymes”. The findings provide a new method for developing functional germinated Fagopyrum esculentum foods.
Objective To establish a method for the determination of malachite green, crystal violet, leucomalachite green and leuco crystal violet in fish by solid-phase extraction (SPE) combine with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods The sample was subjected to protein precipitation and extraction with acetonitrile, followed by pass-through purification using an HMR-Lipid SPE column. The analytes were then separated by the BEH shield C18 chromatographic column using a mobile phase gradient with acetonitrile and ammonium acetate. The positive ion mode of the electrospray ionization source was used for multiple reaction monitoring (MRM) scanning, and the internal standard method was used for quantification. Results The linear ranges of the 4 kinds of target analytes were 0.20-10.00 ng/mL, with correlation coefficient (r) more than 0.999. The limit of detection was 0.05 μg/kg. The recoveries at 3 spiking levels (2, 5, 10 μg/kg) were 80.1%-105.2%, and the relative standard deviations were 1.2%-14.3%. Conclusion The method is rapid, sensitive and accurate, and is suitable for the determination of malachite green, crystal violet and their leuco metabolites in fish. It can provide support for quality control and market supervision.
Objective To systematically analyze the main chemical components and evaluate the quality of Siraitia grosvenorii fruits. Methods High performance liquid chromatography (HPLC) was employed to determine mogroside V, total sugar, vitamin C, moisture and water-soluble extracts in samples of different cultivars (Yongqing 1, Bolin 3, Nongyuan B6 and Qingpi 3), supplemented with additional tests for mogroside V content to enhance data integrity. After the data were standardized, multidimensional analysis including correlation analysis, principal component analysis, and hierarchical cluster analysis was conducted to assess fruit quality. Results Certain variations were observed in different indicators of Siraitia grosvenorii fruits, with coefficients of variation ranging between 5.28% and 35.38%. Several parameter groups exhibited statistically significant correlations at P<0.05 (significant) or P<0.01 (highly significant) levels. The 3 principal components were proposed in principal component analysis, and the contribution rate of cumulative variance was 91.13%. Through hierarchical cluster analysis (squared euclidean distance 11.5), the samples were categorized into 4 distinct groups. The Siraitia grosvenorii in groups Ⅰ and Ⅱ exhibited superior comprehensive performance, while those in group Ⅳ demonstrated relatively poorer overall quality. Conclusion The classification of Siraitia grosvenorii provides a data-driven reference for its cultivation, processing and application, thereby facilitating the enhancement of its quality and practical value.