Objective To explore the molds contamination of oyster sauce after open-cap and deterioration, and isolate and identify the contaminating molds. Methods In this study, the 6 kinds of oyster sauce in 9 different home kitchen environments were used as research objects, and the molds in the deteriorated oyster sauce were separated by the three-point separation method, combined with morphological characteristics and ITS sequence analysis for identification. Results The molds contamination in oyster sauce in the home kitchen environment mainly were due to the dominant growth of microorganisms in the environment in the oyster sauce. A total of 35 strains of molds 16 genera, were isolated from the deteriorated oyster sauce, of which 9 strains of Penicillium, 4 strains of Talaromyces and 4 strains of Aspergillus were isolated, which accounted for 25.71%, 11.42% and 11.42% of the total number of strains isolated, respectively. Conclusion Penicillium, Talaromyces and Aspergillus are the main moulds responsible for the deterioration of open-cap oyster sauce in the home kitchen environment, which can provide a research basis for the quality and safety control of oyster sauce products in the process of use.

Cancer is one of the major diseases with the highest mortality rate in the world, and its prevention and treatment have been the focus of academic research. Tea pigments are a class of polyphenol oxidative polymers from tea leaves, which are mainly classified into theaflavins, thearubigins and theabrownins. They are rich in active phenolic hydroxyl groups and other active groups, and also have antioxidant, anti-inflammatory, antibacterial, anticancer and other bioactive functions. In recent years, tea pigments have received more and more attention in the field of anticancer research due to their naturalness, safety and high efficiency. This paper reviewed the formation of different tea pigments and their biological activities, systematically elaborated the potential mechanisms of action on cancer cells, mainly including inhibition of cellular value-addition, induction of apoptosis, regulation of cell cycle, control of cellular signal pathways, and regulation of intestinal flora. This provides a theoretical basis for expanding the application of tea pigments in ameliorating diseases, developing functional foods and expanding industrial fields.

Objective To prepare a high-titer monoclonal antibody detection kit for aflatoxin B₁ (AFB₁) and rapidly and accurately detect AFB₁ in food. Methods By carbodiimide method, AFB₁ was conjugated with bovine albumin (BSA) to form immune antigen, and with chicken ovalbumin (OVA) to prepare detection antigen. AFB₁ monoclonal antibody was prepared by immunizing mice, cell fusion, screening of hybridoma cells, inducing ascites in vivo, isolation and purification, and a kit for rapid detection of AFB₁ was developed. Results The prepared monoclonal antibody had a titer of up to 1:27 w and showed weak cross-reactivity to Shentuqumycin, with a reaction rate of 13%. No cross-reactivity was observed with the other 2 compounds. The relative standard deviation of the intra- and inter-batch tests for the spiked samples was 2.6%-3.6% and 5.0%-8.0%, respectively. The recoveries were 89.82%-103.64%. The detection sensitivity (median inhibitory concentration value) was 650 pg/mL, with a detection range of 156-5000 pg/mL with the limit of detection of 100 pg/mL. When AFB₁ content was detected in corn flour from different origins, the detection results were 9.756, 2.483, 3.995, 39.080 and 7.831 μg/kg. Conclusion This research has prepared high-titer monoclonal antibodies against AFB₁. These antibodies can not only be utilized for the development of test kit detection experimental methods but also lay the foundation for the development of rapid test strips based on AFB₁ monoclonal antibodies and the colloidal gold method.

Objective To establish an analytical method for the determination of gamithromycin residues in raw milk based on matrix external standard method combined with through type purification column (EMR-Lipid) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods The samples were extracted with acid acetonitrile, purified by the EMR-Lipid through type purification column, gradient eluted through a BEH C₁₈ chromatographic column. Detection was carried out in the electrospray positive ion multiple reaction mode, and quantification was performed using the matrix external standard method. Results Calibration curves were linear in the range of 0.5-20.0 ng/mL with correlation coefficients more than 0.99. The limit of detection (LOD) was 0.5 μg/kg, limit of quantification (LOQ) was 1.0 μg/kg. Gamithromycin showed a matrix enhancement effects in raw milk. After matrix blank curve correction, the average recoveries of gamithromycin at different spiked concentrations ranged from 74.0% to 77.0%, and the relative standard deviations (RSD) of the determination results were from 3.92% to 4.57%. Conclusion This method is accurate, sensitive, stable, simple, and easy to operate, it can be used for the rapid determination and quantitative analysis of gamithromycin residues in raw milk, providing technical support for monitoring the residual amount of gamithromycin in raw milk.

In recent years, the safety concerns arising from the illegal use of drugs in bean sprouts have become increasingly prominent. Therefore, the effective detection of various illicitly used drugs in bean sprouts is crucial to ensuring consumer health. This review introduced the categories, functions, and hazards of common prohibited additives in bean sprouts, including plant growth regulators, antibiotics, and fungicides. It provided an overview of the current situation of supervision, standard detection methods, and risk assessment. At the same time, the review analyzed the application, advantages, and disadvantages of different pretreatment and purification methods applied in the determination of various prohibited additives. Furthermore, in view of several potential hazardous substances with high detection rates in bean sprouts, the existing detection methods were expounded and evaluated with the advantages and disadvantages. Finally, this article summarized the research progress on simultaneous multi-drug residue detection in bean sprouts, and proposed future directions. The aim is to provide a reference for high-throughput screening of various additives in bean sprouts, establish relevant standards, and offer technical support for the scientific and rational quality control of bean sprouts.

Objective To investigate the effects of aging time on the volatile flavor components of soy sauce. Methods Differences in volatile aroma components between black bean soy sauce and soybean meal soy sauce aged at different times were analyzed using electronic nose combined with headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and key aroma components were identified using odor activity value (OAV) method. Results A total of 1227 kinds of volatile substances were detected in 6 kinds of soy sauce samples with different aging times, mainly including 265 kinds of esters, 155 kinds of terpenes, 153 kinds of ketones, 137 kinds of heterocyclic compounds, 104 kinds of alcohols, 77 kinds of acids, 72 kinds of aldehydes, 59 kinds of phenols, 54 kinds of hydrocarbons, 50 kinds of amines, 30 kinds of aromatic hydrocarbons, 27 kinds of ethers, 26 kinds of nitrogen-containing compounds, 9 kinds of sulfur-containing compounds, and 9 kinds of halogenated hydrocarbons. With the increase of aging time, the types and relative content of volatile compounds in black bean soy sauce and soybean bean soy sauce showed significant differences (P<0.05), and the key aroma components contribute significantly to the overall flavor characteristics. Electronic nose technology could effectively distinguish the volatile aroma characteristics of soy sauce with different aging times, and was consistent with the trend of changes in volatile flavor compounds. A total of 132 kinds of key aroma components (OAV>1) were identified through OAV, among which aldehydes, phenols, and terpenes contributed the most to the overall aroma of soy sauce. Conclusion This study reveals the influence of different aging times on the volatile components and aroma quality of black bean soy sauce and soybean meal soy sauce, providing theoretical and experimental references for the improvement of soy sauce and flavor quality.

Objective To explore a method that can monitor the immunoaffinity column capacity of zearalenone (ZEN) in real time during detection. Methods The 2 kinds of artificial structural analogues of ZEN (α-ZEL-G and β-ZEL-G) were synthesized by esterification of α-zearalanol (α-ZEL) and β-zearalanol (β-ZEL) with glutaric anhydride in this study. The products were purified and identified by fluorescence, ultraviolet and high-resolution mass spectrometry. A competitive enzyme-linked immunosorbent assay (ELISA) curve was established using the same antibody with immunoaffinity columns, and their affinity with the antibody was compared by half maximal inhibitory concentration (IC₅₀). α-ZEL-G and β-ZEL-G were used as column capacity tracers and added to the immunoaffinity column together with different concentrations of ZEN to explore a method for real-time monitoring of immunoaffinity column capacity. Results The IC₅₀ of the competitive ELISA curves of ZEN, α-ZEL-G and β-ZEL-G were 2.0, 1.3 and 10.0 ng/mL, respectively, indicating that the affinity of α-ZEL-G with antibody was slightly higher than that of ZEN, while the affinity of β-ZEL-G with antibody was significantly lower than that of ZEN with antibody. The experimental results showed that: α-ZEL-G in immunoaffinity columns with different column sizes would affect the recovery rates of ZEN. Whereas the recovery rates of ZEN with different concentration were more than 80% while the adding concentrations of β-ZEL-G was 50% of the column capacity. Conclusion β-ZEL-G with lower antibody affinity is more suitable for real-time monitoring of column volume. It shows good application results in the test of actual samples.

Objective To explore the protective effects of Panax notoginseng fibrous root extract on alcoholic liver disease in mice. Methods A total of 50 male C57BL/6J mice were randomly divided into 5 groups of 10 mice each: The control group, the model group, the low dose group (67.5 mg/kg), the medium dose group (135.0 mg/kg) and the high dose group (270.0 mg/kg). The control group and the model group were gavaged with pure water, while the Panax notoginseng fibrous root extract groups were given with the corresponding concentrations of the test substance at 20 mL/kg. The Panax notoginseng fibrous root extract groups and model group were gavaged with 40% ethanol (10 mL/kg) 5 hours late for 14 days. The Panax notoginseng fibrous root extract groups and model group were fasted for 16 hours after the last gavage, then each was given 40% ethanol at 20 mL/kg. After weighing the fasting body weight of each group of mice, blood was collected from the abdominal aorta and the liver was removed and weighed. Finally, determined the biochemical indices of serum and liver, and the levels of interleukin-1β (IL-1β) and interleukin-6 (IL-6) in liver. Results Compared with the model group, the medium and high dose groups of the serum triglyceride (TG), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were significantly decreased (P<0.05 or P<0.01). But the superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GSH-Px) in liver was significantly increased (P<0.05 or P<0.01), while the content of malondialdehyde (MDA) was extremely significantly decreased (P<0.01). The content of TG in liver of high dose group was lower than the model group (P<0.01), the difference was statistical significance. Besides, the levels of IL-1β of the low and high dose groups were significantly decreased compared with the model group (P<0.05 or P<0.01). Conclusion The Panax notoginseng fibrous root extract has a good protective effect on hepatic injury induced by alcohol in mice.

Objective To explore the effects of common food preservatives on the abundance and flora structure of antimicrobial-resistant bacteria in Crassostrea gigas. Methods The control group was refrigerated at 4 ℃, and the experimental group was refrigerated at 4 ℃ after soaking with potassium sorbate, chitosan, Nisin and ɛ-polylysine, respectively. The change of antimicrobial-resistant bacteria content in Crassostrea gigas treated with different food preservatives was analyzed by antimicrobial-resistant plate counting method. The structural changes of antimicrobial-resistant bacteria were analyzed by high-throughput sequencing of 16S rRNA amplicon. Results Potassium sorbate and chitosan could significantly reduce the number of resistant bacteria of single and multiple antimicrobials; Nisin significantly reduced the number of resistant bacteria to co-trimoxazole, chloramphenicol, gentamicin, and bacteria resistant to 2, 3, or 4 antimicrobials simultaneously; ε-polylysine significantly decreased the number of ciprofloxacin resistant bacteria, co-trimoxazole resistant bacteria, chloramphenicol resistant bacteria, gentamicin resistant bacteria and resistant bacteria resistant to 3 or 4 kinds of antimicrobials at the same time. Potassium sorbate and chitosan had a significant effect on the composition of tetracycline and ciprofloxacin resistant bacteria, and Nisin and ε-polysine had a significant effect on the composition of co-trimoxazole resistant bacteria. Conclusion The research results show that the content of antimicrobial-resistant bacteria in Crassostrea gigas can be controlled by applying appropriate food preservatives, food preservatives can affect the composition of culturable antimicrobial-resistant bacteria in Crassostrea gigas and different preservatives can inhibit specific antimicrobial-resistant bacteria, which provides a new idea for the establishment of antimicrobial-resistant bacteria control techniques in Crassostrea gigas.

Objective To evaluate the edible safety of marine aquaculture Monostromanitdum along the coast of Naozhou Island. Methods Using 4 kinds of different collection times of Monostromanitdum as research objects, microwave digestion, inductively coupled plasma mass spectrometry, and atomic fluorescence spectroscopy were used to analyze the content of 5 kinds of heavy metals, Cr, As, Pb, Hg, and Cd, in Monostromanitdum samples, and microbial indicators were determined. Using acute oral toxicity experiments on mice, the food safety of Monostromanitdum was evaluated by analyzing indicators such as drinking water, diet, body weight, organ coefficient, mortality rate, and appearance of mice. Results The content of Cr, As, Pb, and Hg in the sample far exceeded the food safety content specified by the national standard, with the maximum being 29.20, 12.12, 3.59 and 3.70 times the limit values, respectively. The total number of bacterial colonies in the samples exceeded 50 CFU/g. The mice in the group administered with Monostromanitdum by gavage showed signs of death, with organ coefficients increasing in all organs except for the liver, and the appearance changes consistent with heavy metal poisoning. Conclusion There are safety risks associated with consuming unprocessed Monostromanitdum, and the safety of direct consumption is relatively low.