Objective To investigate the pollution of organophosphorus flame retardants (OPFRs) in soil and nuts in the primary Carya illinoensis production areas of Anhui Province, and evaluate the ecological risk and human health risk. Methods A total of 15 soil and nut samples were collected from the main production areas of Carya illinoensis in Anhui Province, and the pollution characteristics of 14 kinds of OPFRs were analyzed. The ecological risk of soil was evaluated using the risk quotient (RQ) method, and the human health risk of consuming nuts was assessed using a health risk assessment model. Results The concentration range of OPFRs in soil samples from Carya illinoensis production areas in Anhui Province was 162.33-394.48 μg/kg, with an average of 305.83 μg/kg. Tris(2-ethylhexyl)phosphate (TEHP) had the highest detection concentration, at 52.62 μg/kg. The concentration range of OPFRs in nut samples was 127.57-310.81 μg/kg, with an average of 223.93 μg/kg. Tris(2-ethylhexyl) phosphate (TEHP) had the highest detection concentration, averaging 46.82 μg/kg. The RQ values of 11 kinds of OPFRs ranged from 3.50×10^-5 to 0.47, with tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), triphenyl phosphate (TPhP), and 2-ethylhexyl diphenyl phosphate (EHDPP) having RQ values between 0.1 and 1.0. The remaining RQ values were all less than 0.1. The health risk assessment of human intake of pecan showed that the hazard quotient (HQ) values of children and adults were both less than 0.1, and the risk of intake of TBEP was higher in children and adults, with the HQ value of adults slightly higher than that of children. Conclusion There is a particular ecological risk of OPFRs in the soil of some production areas of Carya illinoensis in Anhui Province, and the residues of OPFRs in nuts can be ignored in terms of human health risk. This study provides a basis for the safety assessment of novel pollutants in the soil and nuts of Carya illinoensis production areas.

Objective To understand the contamination level of glycidyl esters (GE) in edible vegetable oils and to evaluate the dietary exposure risk of GE in Shanghai residents. Methods Based on the monitoring data of GE in edible vegetable oil sold in Shanghai in 2024, combined with the vegetable oil consumption data of Shanghai residents in 2024, the GE exposure of Shanghai residents via vegetable oil was calculated by simple distribution assessment method, and the margin of exposure (MOE) method was used to assess the health risk. Results The detection rate of GE in 178 edible vegetable oils was 94.4%, with an average content of 360.8 μg/kg and a maximum value of 5470.0 μg/kg. According to the EU regulations on the limit values of GE in vegetable oils, it was found that the exceeding standard rate of GE in vegetable oil was 5.6%. The mean content of GE in rice oil (1169.3 μg/kg) was the highest, followed by camellia seed oil (657.8 μg/kg) and corn oil (499.0 μg/kg). The mean daily exposure and 95th percentile exposure of GE from edible vegetable oils in Shanghai residents aged ≥3 years old were 0.208 and 0.497 μg/kg bw, the MOE values were 11538 and 4829, respectively, and P₉₅ MOE was less than 10000. The mean MOE value of GE exposure through vegetable oil in residents aged 3 to 17 years old was less than 10000. The P₉₅ MOE values of GE exposure through vegetable oil in 4 different age groups were all less than 10000. Conclusion The health risk of GE intake via edible vegetable oil in Shanghai residents is generally at an acceptable level. However, the health risks of GE exposure for individuals aged 3 to 17 year old and those with high consumption of vegetable oil still need to be focused.

Objective To compare the taste characteristics, physical and chemical indicators of preserved mustards samples in market, and statistically analyze the correlation between taste quality and physical and chemical indicators. Methods The 22 samples of preserved mustards from Zhejiang, Sichuan and Hunan were collected, and the taste characteristics of preserved mustards were analyzed by artificial sensory evaluation and electronic tongue, the physical and chemical indicators such as moisture content, total acid, amino acid nitrogen, trichloroacetic acid (TCA) soluble peptides, nitrite, and reducing sugar content were analyzed. Results The saltiness and umami of preserved mustards were prominent, and the acidity intensity of different preserved mustards varied greatly. Umami was significantly negatively correlated with sourness and saltiness (P<0.01), and significantly negatively correlated with bitter aftertaste (P<0.05). Water content had a great influence on the taste quality of preserved mustards, and was significantly positively correlated with the taste (P<0.05). The salt content was significantly negatively correlated with the total acid content (P<0.01). Conclusion The taste characteristics and physical and chemical indexes of different preserved mustards samples are very different, and some preserved mustards have high salt content, so it is necessary to establish quality standards; the taste quality and physical and chemical indexes of preserved mustards from different origins does not show obvious regional characteristics; there is a negative correlation between the indexes of carbohydrate fermentation products and protein fermentation products in preserved mustards.

Objective To understand the residual levels of chlorpyrifos in vegetables and fruits in Shanghai in 2014—2023, and evaluate the dietary exposure risk of chlorpyrifos in vegetables and fruits. Methods A number of different varieties of vegetables and fruits in Shanghai were inspected and monitored for the detection of chlorpyrifos from 2014 to 2023. Combined with the food consumption data of residents in Shanghai in 2013, dietary exposure risk assessment of chlorpyrifos were conducted by point assessment method. The assessment results were compared with the acute reference dose (ARfD) and acceptable daily intake (ADI) to assess the acute and chronic exposure risk of chlorpyrifos in vegetables and fruits in residents in Shanghai. Results The quantity of vegetables samples was 33796, the detection rate was 0.97%, the average value was 0.00131 mg/kg, and the exceedance rate was 0.46%. The quantity of fruits samples was 9228, the detection rate was 5.26%, the average value was 0.00320 mg/kg, and the exceedance rate was 0.00%. The acute exposure of chlorpyrifos residues ingested through vegetables and fruits were 0.0432 mg/kg bw and 0.0141 mg/kg bw, the ratio of acute exposure to ARfD respectively were 43.19% and 14.15% among the population aged 3 and above. The chronic exposure of chlorpyrifos residues ingested through vegetables and fruits were 5.34×10^-6 mg/kg bw and 8.43×10^-6 mg/kg bw, the ratio of chronic exposure to ADI respectively were 0.053% and 0.084%. Conclusion Both the acute and chronic exposure risks of chlorpyrifos ingested through vegetables and fruits in residents are low in Shanghai.

Objective To investigate the prevalence, virulence phenotypes, and drug resistance phenotype of Vibrio parahaemolyticus in freshwater food, seafood, and ready-to-eat food in Yangzhou. Methods Freshwater food, seafood and ready-to-eat food samples were collected from 9 sampling points in Yangzhou markets for isolation and identification of Vibrio parahaemolyticus. The motility, hemolytic activity, and drug resistance phenotype of the isolates were analyzed. Results In 2023, a total of 289 samples were collected in the Yangzhou market, from which 63 strains of Vibrio parahaemolyticus were isolated, with an isolation rate of 21.80%. Among them, the isolation rate of freshwater food was 45.35% (39/86), seafood 28.75% (23/80), and ready-to-eat samples 0.81% (1/123), indicating a higher isolation rate in freshwater food compared to seafood in the markets of Yangzhou. The proportion of highly motility strains in freshwater food isolates was 30.77%, higher than that of the seafood isolates (17.39%). However, the proportion of strains with high hemolytic activity was 53.85% in freshwater food isolates, slightly lower than the 60.87% in seafood isolates. Antibiotic resistance profiling showed that all Vibrio parahaemolyticus isolates were resistant to ampicillin and cefazolin, while they were resistant to ceftazidime, tetracycline, ciprofloxacin, chloramphenicol, amikacin, meropenem and gentamicin. Conclusion This study highlights a high detection rate of Vibrio parahaemolyticus in Yangzhou markets and reveals differences in virulence and antibiotic resistance among isolates from different sources, offering valuable insights for monitoring and controlling the pathogen.

Objective To investigate the contamination status and conduct a risk assessment of foodborne pathogens in food samples from Baotou City, Inner Mongolia, from 2016 to 2023. Methods According to the requirements of the Inner mongolia autonomous region food safety risk monitoring plan—Microbiological monitoring, food samples were collected from 10 counties and districts in Baotou City between 2016 and 2023. Detection of foodborne pathogens was performed following standard operating procedures. Results Over the 8-year period, a total of 1358 food samples from 17 major categories were collected, and 485 strains of pathogenic microorganisms belonging to 14 species were detected, with an overall detection rate of 26.58% (361/1358). Among the 11 categories of food samples with detected pathogens, meat and meat products, as well as aquatic products and their products, showed higher detection rates of 42.35% (227/536) and 47.78% (43/90), respectively. Food samples from sampling points such as farmers' markets and farming sites were heavily contaminated, with detection rates of 42.13% (75/178) and 61.22% (30/49), respectively. Among the pathogens, Vibrio alginolyticus and Campylobacter had higher detection rates of 40.00% (8/20) and 50.22% (113/225), respectively. The positive detection rate of monitored samples increased annually, rising from 1.05% (2/190) in 2016 to 50.00% (100/200) in 2023. Conclusion The contamination level of foodborne pathogens in meat and meat products, as well as aquatic products and their products, is relatively high in Baotou City. Sampling points such as farmers' markets pose a risk of causing foodborne diseases.

Objective To establish an analytical method for the determination of 146 kinds of pesticide residues in animal derived foods by enhanced matrix removal-lipid dispersion solid phase extraction (dSPE EMR-Lipid) and purification technology coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS). Methods The 5 g sample were added to 2 mL ultrapure water, extracted with acetonitrile, freezed for 10 min, separated with QuEChERS EN-extraction package, cleaned-up with dSPE EMR-Lipid, then was detected by GC-MS/MS in dynamic multi-reaction monitoring (DMRM) mode. The analytes were quantified by matrix-matched standard curve method. Results The results showed that 146 kinds of pesticides had good linearities in the concentration of 5-320 μg/L, the linear correlation coefficient of the compounds were greater than 0.9939, and the limits of detection of the method were 0.04-10.91 μg/kg, the limits of quantification were 0.11-32.72 μg/kg. The average recoveries of 146 kinds of pesticides at the spiked level of 0.01, 0.02 and 0.10 mg/kg ranged from 61.3% to 119.3%, relative standard deviations were 0.15%-16.02%. Conclusion The method is simple in pre-treatment, convenient in operation, rapid, sensitive and accurate in detection, can meet the simultaneous detection requirements for multiple pesticide residues. It is suitable for preliminary screening and quantitative detection of multiple pesticide residues in animal derived food.

Objective To optimize the process of preparing low methoxy pectin-lentinan gel beads by combining low methoxy pectin and lentinan with calcium lactate, and characterize the structure of gel beads prepared under the optimal process conditions. Methods The effects of calcium lactate concentration, curing time, and curing temperature on the hardness of gel beads were investigated through single factor experiment and response surface methodology, and the structure of gel beads was characterized by Fourier transform infrared spectroscopy, texture analysis, rheological analysis and scanning electron microscopy. Results The optimum preparation process of low methoxy pectin-lentinan gel beads was determined by response surface methodology as calcium lactate concentration of 6.2%, curing time of 44 min, and curing temperature of 48 ℃. Under these conditions, the hardness of the gel beads was 35.60 gf. Compared with low methoxy pectin gel beads, low methoxy pectin-lentinan gel beads produced stronger hydrogen bond interaction, and their elasticity, cohesion, and dynamic modulus were improved. Conclusion Lentinan can effectively improve the mechanical properties and texture properties of low methoxy pectin gel beads, and this study will provide a reference for the improvement of pectin gel bead systems.

Objective To investigate the induced expression level and enzymatic properties of recombinant bacterial laccase and to improve the degradation efficiency of sulfadiazine antibiotics by bacterial laccase. Methods In this study, the effects of induction temperature, induction time, and concentration of isopropyl β-D-thiogalactopyranoside (IPTG) on enzyme expression were investigated by one-way experiments. The enzymatic properties of recombinant bacterial laccase were also investigated by both pH and temperature. Results The degradation of sulfadiazine by recombinant bacterial laccase at 24 h was 50%. The optimal conditions for the expression of recombinant bacterial laccase in Escherichia coli BL21 (DE3) were as follows: Induction temperature of 16 ℃, induction time of 16 h, and IPTG concentration of 0.2 mmol/L. The optimal pH was 3, and the stability was best at pH 7, with the enzyme activity reaching 150% in 6 h. The optimal temperature was 80 ℃, and the thermal stability was best at 70 ℃, with the enzyme activity increasing to 120% in 1 h. The half-life was about 6 h. Conclusion This study provides an experimental basis for the application of bacterial laccase in the degradation of sulfadiazine antibiotics and lays down a theoretical basis for the future study of its potential application in the industry.

Objective To establish a method for the simultaneous determination of 24 kinds of β-blockers in eggs by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Methods The 80% acetonitrile aqueous solution was used as extraction solvent, QuEChERS was used as purification method, acetonitrile-saturated n-hexane was used for degreasing, Waters ACQUITY UPLC BEH C₁₈ (2.1 mm×100 mm, 1.7 μm) column was used for gradient elution with acetonitrile-0.1% formic acid solution as mobile phase. The ionization mode was spray positive ion mode, and quantitative analysis was performed using multiple reaction monitoring mode. The quantitative method was external standard. Results The 24 kinds of β-blockers in eggs showed a good linear relationship (r≥0.9963) in the concentration range. When the sample weight was 1 g (accurate to 0.001 g) and the final volume was 2 mL, the limit of detection was 3 μg/kg, and the limit of quantitation was 10 μg/kg. The average recoveries were 63.6%-108.0%, and the relative standard deviations (n=6) were 0.9%-7.4%. Conclusion This method has the advantages of simple operation, high accuracy, high sensitivity and good reproducibility, and can provide technical reference for the analysis of β-blocker in fresh eggs in daily life and sports events.