At present, the demand for acaricides in agricultural production in China ranks second only to insecticides. As an important chemical pollutant affecting the safety of agricultural products, acaricides, represented by heterocyclic compounds, have relatively stable structures, long half lives, are not easily degraded, and are more likely to remain on the surface or inside of food, causing serious food safety problems. The development of economically effective detection methods for heterocyclic acaricides has become a current research trend, which is of great significance for ensuring the safety of public vegetable baskets, promoting green ecological agriculture, and advancing high-quality agricultural development. Immunoassay methods are widely used in the field of pesticide residue detection due to their fast, simple, efficient, and sensitive characteristics. This paper reviewed the research progress of immunological analysis methods for heterocyclic acaricides pesticides from the aspects of synthesis of haptens, preparation of antibodies, and their detection applications in agricultural product matrices, analyzed the challenges and future development prospects of immunoassay methods, which have certain reference value for the detection of heterocyclic acaricides residues.

Objective To establish a method for simultaneous determination the content of 4 kinds of human milk oligosaccharides [2'--fucosyllactose (2'-FL), 3'-sialic acid (3'-SL), 6'-sialic acid (6'-SL) and lactose-N-neotetraose (LNnT)] in milk powder by liquid chromatography-fluorescence method. Methods The samples were dissolved in water, enzymolized with amyloglucosidase or β-galactosidase, derived with 2-aminobenzamide (2-AB) and 2-methylpyridine borane (2-PB), and separated by amide bonding column, detected by fluorescence detector, and quantitated by internal standard methods. Results The 4 kinds of milk oligosaccharides had a good linear relationship in the concentration range of 10-600 μg/mL, and the correlation coefficients (r²) were more than 0.999. The limits of detection and quantification of 4 kinds of milk oligosaccharides were 0.94-2.31 mg/100 g and 3.12-7.69 mg/100 g, respectively; the recovery rates of 4 kinds of milk oligosaccharides were 97.7%-101.5%, and the relative standard deviations (RSD) (n=7) were 0.53%-3.09%. Conclusion This method does not have high requirements for people, equipments and environment for determining the content of 4 kinds of milk oligosaccharides in milk powder. The pre-treatment operation is simple, and it has good accuracy and precision. It can provide a reference for the quality control method of human milk oligosaccharides in milk powder.

Objective To establish a method for the determination of 25 kinds of illegal additives in candy by dispersive solid phase microextraction extraction coupled with ultra performance liquid chromatography-tandem mass spectrometry. Methods The samples were extracted with 50% methanol water, purified by dispersive solid phase microextraction extraction and separated by ACQUITY UPLC TSS T3 column. The samples were then eluted with ammonium formate aqueous solution and ammonium acetonitrile as mobile phase by gradient elution. The samples were determined by ultra performance liquid chromatography-tandem mass spectrometry and quantified by external standard method. Results The results showed that the 25 kinds of illegal additives had good linearity in the range of 2.00 to 50.00 µg/L with a correlation coefficient (r²) greater than 0.99, recoveries were between 65.1% and 99.3%, relative standard deviations were 1.1% to 5.0%, and limit of detection was 0.05 mg/kg and limit of quantification was 0.10 mg/kg. The method was applied to the detection of 105 batches of samples, in which one batch of compressed candy was found to contain xinlisita, and two batches of candy were found to contain dipropylphenidate. Conclusion The method is purified by dispersive solid phase microextraction extraction and detected by ultra performance liquid chromatography-tandem mass spectrometry. The method has good accuracy and high sensitivity, and can meet the detection requirements of 25 kinds of illegal additives in candy.

Objective To optimize the decolorization process of Cistanche deserticola polysaccharides and explore their antioxidant activity. Methods Using activated carbon as a decolorizing agent, the effects of 4 factors including activated carbon dosage, decolorization temperature, decolorization time, and pH on decolorization rate and polysaccharide recovery rate were investigated. Based on single factor experiments, the decolorization process of Cistanche deserticola polysaccharide extract was optimized using response surface methodology. Using an in vitro antioxidant activity evaluation method, the free radical scavenging ability of 1,1-diphenyl-2-picrylhydrazine (DPPH), total reducing ability, hydroxyl radical scavenging ability, and 2,2'-azino bis(3-ethylbenzothiazole- 6-sulfonic acid) diammonium salt (ABTS) cation free radical scavenging ability of the polysaccharides from Cistanche deserticola were determined. Results The optimal decolorization process conditions for the extract of polysaccharides from Cistanche deserticola were as follows: Active carbon dosage 20%, decolorization temperature 37 ℃, decolorization time 49 min, pH 5.03. Under these optimal conditions, the decoloizration rate and polysaccharide recovery rate were 62.66% and 96.16%, respectively. After decolorization, the capabilities of scavenging DPPH radical and hydroxyl free radical was significantly increased, while the capabilities of scavenging ABTS anion radical was significantly decreased. Conclusion The decolorization process is easy to operate, with good decolorization effects and polysaccharide recovery rate. It has important application value and provides basis for the later research and development of Cistanche deserticola polysaccharide.

Objective To establish a method for the simultaneous determination of functional components in extracts from 7 kinds of medicinal and food homologous substances: Pueraria lobata, Sophora japonica, Lonicera japonica, Cistanche deserticola, Siraitia grosvenorii, Panax ginseng and Hovenia dulcis by high performance liquid chromatography (HPLC). Methods The analysis was conducted using an Agilent Eclipse XDB-C₁₈ column (4.6 mm× 250 mm, 5 μm) with a mobile phase gradient elution of acetonitrile-0.1% phosphoric acid at a flow rate of 0.6 mL/min, a column temperature of 30 ℃, a detection wavelength of 210 nm, and an injection volume of 5 μL. This method was employed to quantify the content of puerarin, rutin, chlorogenic acid, echinacoside, verbascoside, mogroside V, ginsenoside Re and dihydromyricetin. Results The results demonstrated that 8 kinds of functional components exhibited excellent linear relationships within their respective concentration ranges, with correlation coefficients (r²) exceeding 0.999. The limits of detection ranged from 0.02 to 1.88 mg/L, and the limits of quantification ranged from 0.08 to 3.62 mg/L. The precision experiment results showed that the relative standard deviation (RSD) was less than 3%, the average recoveries of spiked samples ranged from 95.49% to 109.87%. Conclusion This method is simple, rapid and highly accurate, making it suitable for the qualitative and quantitative analysis of the functional components in the aforementioned 7 kinds of medicinal and food homologous substances.

Objective To explore the dose effects and molecular mechanism of B-type proanthocyanidins trimer, the main active component of Litchi chinensis Sonn pulp phenolics, on hepatocyte triglyceride (TG) deposition. Methods HepG2 cell steatosis model induced by oleic acid (OA) was treated with different mass concentrations (0.5-10.0 μg/mL) of B-type proanthocyanidins trimer. The content of TG and the expressions of genes related to lipid absorption, transport and oxidation, together with apoptosis of hepatocytes, were detected in oleic acid loaded hepatocytes. Results B-type proanthocyanidins trimer (0.5-10.0 μg/mL) all significantly inhibited TG accumulation in oleic acid-loaded hepatocytes, while no dose dependence was observed. Low-dose (1.0 μg/mL) B-type proanthocyanidins trimer inhibited hepatocyte apoptosis by increasing the relative expression ratio of Bcl-2 to Bax, thereby reducing TG accumulation in hepatocytes. In addition to the above-mentioned pathway, medium/high-dose (5.0 μg/mL, 10.0 μg/mL) B-type proanthocyanidins trimer also inhibited lipid absorption in hepatocytes by down-regulating CD36 and FATP2 expression, and promoted hepatocytes lipolysis by up-regulating ACSL1 and CPT1α expression, hence reducing TG accumulation in hepatocytes. Conclusion B-type proanthocyanidins trimer of Litchi chinensis Sonn pulp can inhibit lipid absorption, promote β-oxidation of fatty acids and inhibit excessive apoptosis of liver tissue cells, thereby improving lipid metabolism and preventing fatty liver.

Objective To optimize the preparation process of Brassica rapa L. polysaccharide oral liquid and test its quality. Methods Graded alcohol precipitation was used to study the yield of crude polysaccharides of Brassica rapa L. at different ethanol concentrations. The optimal formulation of oral solution of Brassica rapa L. polysaccharide was screened by one-way and orthogonal tests, and the quality was tested according to the pharmacopoeia. Results The extraction rates of crude polysaccharide from Brassica rapa L. were 12.8%, 9.2%, 23.2% and 24.8% for the alcohol precipitation group with ethanol concentration of 20%, 40%, 60% and 80%, respectively. The optimal preparation process conditions of oral solution of Brassica rapa L. refined polysaccharide were: 2% addition of Brassica rapa L. crude polysaccharide, 15% addition of honey, 0.6% addition of citric acid and 0.6% addition of sodium citrate. The best preparation process conditions for oral liquid of Brassica rapa L. crude polysaccharide were: 2% addition of Brassica rapa L. crude polysaccharide, 15% addition of honey, 0.6% addition of citric acid, 0.6% addition of sodium citrate. The pH of the oral solution of refined polysaccharide of Brassica rapa L. and the oral solution of crude polysaccharide of Brassica rapa L. were 4-5. The relative density of the oral solution of refined polysaccharide of Brassica rapa L. was 1.106 g/mL. The relative density of the oral solution of crude polysaccharide of Brassica rapa L. was 1.100 g/mL. Conclusion The optimal preparation process conditions for refined polysaccharides from Brassica rapa L. and crude polysaccharides from Brassica rapa L. are the same, but the taste, odor, and appearance of the former are superior to those of crude polysaccharides from Brassica rapa L.. However, the extraction process for refined polysaccharides from Brassica rapa L. is slightly more complex and not suitable for mass production in factories.

Objective To develop and comprehensively evaluate the composite liquid beverage (CLB) based on the same source for Lonicera caerulea and other medicinal and edible materials. Methods Based on the binding rate of cholate, Lonicera caerulea, Auricularia and Crataegus pinnatifida were selected as the main raw materials and the ratio was optimized. Single-factor experiment, response surface experiment and more objective electronic tongue experiment were used to determine the amount of additives in the formulation, and the changes of physical properties, composition content and functional characteristics of CLB before and after sterilization were measured to evaluate the feasibility of pasteurization. Results The optimal ratio of extracts of Lonicera caerulea, Auricularia and Crataegus pinnatifida was 20:8:5 (V:V:V). The supplemental amounts of excipients were: Erythrolitol 13.00%, carboxymethyl cellulose (CMC) 0.40%, potassium sorbate 0.03%, soybean polysaccharide 0.50%. Before and after CLB sterilization, the polymer dispersity index (PDI) was less than 1, the centrifugal stability coefficient was more than 90%, and the chroma ΔE was less than 2, which showed good stability. The differences in soluble solids, pH, turbidity, centrifugal stability coefficient, hydroxyl radical scavenging rate, and active ingredients before and after CLB pasteurization were not significant, and it had good shear characteristics, indicating the feasibility of the sterilization method. Its viscosity value approached that of milk (0.01 Pa•s), and it had a good drinking taste. Conclusion This study provides a theoretical basis for expanding the development of Lonicera caerulea with poor palatability and the application of plant-derived health beverage.

Objective To explore the effects of dried Dendrobium officinale and fresh Dendrobium officinale on the gut microbiota of normal mice and to provide a reference for its rational development and application. Methods The normal mice were administrated with dried Dendrobium officinale and fresh Dendrobium officinale for 7 days, respectively. The growth of mice was observed, and the mucosa-associated microbiota in the small intestine and colon was detected using the full-length 16S rRNA gene sequencing. Results The results showed that both dried Dendrobium officinale and fresh Dendrobium officinale could control the weight gain of mice, but the weight-control effect of fresh Dendrobium officinale was more significant than that of dried Dendrobium officinale. Both dried Dendrobium officinale and fresh Dendrobium officinale decreased α diversity of mucosa-associated microbiota in the colon. However, fresh Dendrobium officinale increased α diversity of mucosa-associated microbiota in the small intestine, while the effect of dried Dendrobium officinale was the opposite. Moreover, fresh Dendrobium officinale significantly promoted the proliferation of short-chain fatty acid-producing bacteria (Lactobacillus, Faecalibacterium prausnitzii, Butyricicoccus pullicaecorum and Roseburia inulinivorans) in the small intestine and up-regulated metabolic pathways such as lipid metabolism, metabolism of terpenoids and polyketides, carbohydrate metabolism, and xenobiotics biodegradation and metabolism. In colonic mucosa-associated microbiota, dried Dendrobium officinale showed a stronger inhibitory effect on Escherichia coli and Ruminococcus gnavus than fresh Dendrobium officinale. Conclusion The results show that fresh Dendrobium officinale can control body weight and maintain health by promoting the proliferation of beneficial bacteria and up-regulating lipid and carbohydrate metabolism, while dried Dendrobium officinale can inhibit the growth of harmful bacteria, and may help reduce the potential risk of disease.

Objective To establish a specific identification method for Ganoderma lucidum extract, and achieve the synchronous determination of a variety of monosaccharides. Methods The analysis of monosaccharide composition in Ganoderma lucidum extracts was conducted using a pre-column derivatization reversed-phase liquid chromatography method. A quantitative analysis of multi-components by single-marker method was established to determine the monosaccharide content in Ganoderma lucidum extracts. Results Ganoderma lucidum extract from 3 manufacturers contained mannose, glucose and galactose, but the proportion of monosaccharides in 4 batches was significantly different. The content of mannose, glucose and galactose could be determined by one test and multiple evaluation method at the same time. The relative deviation from external standard method was less than 5%, and there was no significant difference, which was feasible. Conclusion This study analyzes the monosaccharide composition and monosaccharide ratio in Ganoderma lucidum extract, which can serve as an auxiliary means for identifying the quality of Ganoderma lucidum polysaccharides in Ganoderma lucidum extract. It provides a reference for enterprises to monitor the quality of extracts.