To establish an accurate, sensitive and anti-interferential method for the determination of low-content total anthraquinones in health wine with complex matrix.

Based on the spectrophotometry method specified in 2020 Edition of the technical guiding principles for inspection and evaluation of physicochemical and hygienic indicators of health food, the sample pretreatment was optimized by adjusting sample weight, performing full-volume extraction, reducing the constant volume and adopting centrifugal purification to minimize matrix interference and enhance detection sensitivity. The optimized method was verified using the high performance liquid chromatography method under the item of Polygoni multiflori Radix in the 2025 edition of the Chinese pharmacopoeia as the reference method, and the consistency of the results was evaluated by Bland-Altman analysis.

The optimized method exhibited good linearity in the range of 0–0.0162 mg/mL with a determination coefficient of 0.99998.The limit of detection was 0.009 mg/100 g, and the limit of quantitation was 0.026 mg/100 g. The average spiked recovery at 3 concentration levels was 98.94%, with a relative standard deviation of 1.58%. The 10 batches of samples were determined by the optimized spectrophotometry and the high performance liquid chromatography reference method. The Bland-Altman consistency analysis indicated that the detection results of the 2 methods exhibited consistent trends.

The method is simple, sensitive, robust against matrix interference and accurate. It is suitable for the rapid determination and quality control of low-content total anthraquinones in health wine with complex matrix.

To explore the effective extraction of internal and external morphological features of Citrullus lanatus seeds and the identification of their varieties by applying terahertz (THz) mapping technology.

A total of 120 seeds from 3 common Citrullus lanatus varieties, “Ruixin”, “Langchao 1” and “Xiangxiu”, were selected as experimental samples, and THz transmission spectral images were collected. First, a method based on Sym6 wavelet transform was used for spectral denoising and image correction. Subsequently, correlation coefficient imaging was employed to reconstruct THz pseudo-color images of the seed coat and kernel, and the DeepLab V3+semantic segmentation model was applied to achieve precise segmentation of tissue regions. From the segmented images, 9 morphological parameters were extracted from each of the seed coat and kernel, resulting in a total of 18 phenotypic features, which were used to construct a seed coat feature set, a kernel feature set and an integrated feature set. Variety identification was performed using 3 kinds of machine learning models: extreme learning machine (ELM), random forest (RF), and support vector machine (SVM).

The coefficients of determination between THz imaging measurements and manual measurements for the seed major axis and minor axis reached 0.830 and 0.916, respectively, verifying the high accuracy and reliability of THz technology. In terms of variety identification, the integrated feature set combined with the RF model achieved the best identification performance on the test set, with an average accuracy of 88.0%, showed significant improvement compared to models based on single-tissue features.

This study demonstrates that the THz spectral-based method enables non-destructive and accurate measurement of phenotypic traits in Citrullus lanatusv seeds and effective variety identification, providing a new technical approach for the evaluation of Citrullus lanatus germplasm resources and breeding research.

To establish a rapid and high-throughput qualitative method for analysis of triterpenoids from Ganoderma lucidum by ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS).

Based on the advantages of UPLC-Q-TOF-MS with high separation efficiency and high resolution, the mass spectrometer detection conditions (including the ion detection mode, ion source temperature and collision energy) were optimized. The mass spectral fragmentation patterns and characteristic fragment ions of triterpenoids were summarized, and a standard spectral library of triterpenoids from Ganoderma lucidum was constructed. Meanwhile, sample spiking verification experiments were introduced. Combined with the retention time and accurate mass-to-charge ratio information of spiked samples, actual samples and reference standards, the rapid identification of triterpenoids was realized.

After optimization, the mass spectrometry detection was employed electrospray ionization in negative-ion mode, with an ion source temperature of 450 ℃, a voltage of –4500 V and a collision energy of 45 V. Combined with standard substance comparison and triterpenoid cleavage rules, a total of 32 kinds of triterpenoid components and 5 kinds of unknown triterpenoid components were identified.

This analytical method has excellent separation performance, high sensitivity and strong specificity. It enables rapid qualitative identification and preliminary structural elucidation of triterpenoids from Ganoderma lucidum. It is applicable to the chemical composition characterization and quality control of Ganoderma lucidum and also provides a methodological reference for further research of triterpenoid active substances.

To establish a method for the determination of vitamin B₁ in fresh fruit matrix by ultra performance liquid chromatography and optimize the derivatization and extraction conditions.

Vitamin B₁ in fruit samples was derivatized with alkaline potassium ferricyanide and then extracted using n-butanol. Chromatographic separation was performed on an ACQUITY UPLC BEH C₁₈ column (2.1 mm×100 mm, 1.7 µm). The mobile phase consisted of 50 mmol/L sodium acetate solution and acetonitrile with gradient elution. The flow rate was set at 0.25 mL/min, and the column temperature was maintained at 40 ℃. The excitation and emission wavelengths were 375 nm and 435 nm, respectively, and the injection volume was 1 μL. Qualitative analysis was conducted based on chromatographic retention time, and quantitative detection was carried out via external standard method with standard curve.

Under the best conditions, vitamin B₁ showed a good linear relationship with peak area within the mass concentration range of 0.05–1.00 μg/mL, the correlation coefficient was greater than 0.9998, and the limit of quantitation and limit of detection were 0.80 mg/kg and 0.30 mg/kg, respectively. The accuracy and precision of the method were investigated by using different kinds of fruits as the substrate with low, medium and high concentration levels. The average recovery of vitamin B₁ was 79.6%–112.0%, and the relative standard deviation was less than 4.7%.

The established method is applied to the determination of vitamin B₁ in various fruit samples. This method features simple and rapid sample pretreatment, high accuracy and favorable precision, and is suitable for the rapid determination of vitamin B₁ in large batches of fruit samples.

To investigate a detection method based on near-infrared hyperspectral imaging combined with decision tree algorithm and minimum noise fraction transform (MNF).

Hyperspectral images of seaweed samples containing impurities were acquired using a GaiaSorter-N17E system (spectral range: 900–1700 nm).Following radiometric calibration, MNF was applied for dimensionality reduction and noise removal to extract feature bands. Subsequently, a decision tree classification model was constructed for impurity identification.

Significant spectral differences were observed among different impurities in the near-infrared region. The first several MNF bands contained the main information and effectively highlighted impurity characteristics. The decision tree model clearly distinguished seaweed from sand, wood, charcoal and plastic rope, demonstrating excellent performance in identifying fine plastic rope. The method achieved a high overall classification accuracy of 92.8% and a fast processing speed of approximately 1.6 s per image without requiring extensive training samples.

This method provides effective technical support for automated impurity detection in seaweed and holds significant potential for application in food industry quality monitoring.

To conduct non-targeted screening and risk assessment of non-volatile migrants from food contact paper-based composite materials.

Liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was adopted to comprehensively screen the migration behaviors of non-volatile substances from 2 typical food contact paper-based composites (paper/aluminum/plastic and paper/plastic) under different migration conditions. Risk assessment was performed to assess the safety risks of the detected migrants. Principal component analysis (PCA) was further applied to compare the differences in migration substances between the 2 types of materials.

A total of 38 kinds of non-volatile migrants, including sizing agents, antioxidants and lubricants, were identified from the 2 types of materials in acidic food simulants and high alcohol-containing food simulants. Risk assessment results indicated that 5 kinds of alkyl ketene dimer (AKD) sizing agents migrating from paper/plastic composite films in 95% ethanol posed potential health risks, suggesting that further refined risk evaluation was required. PCA revealed distinguishable differences in the composition of migrants between the 2 kinds of paper-based composites under 95% ethanol migration conditions. The number and migration levels of migrants released from paper/plastic composite films were overall higher than those from paper/aluminum/plastic composites.

The comprehensive migration data demonstrated that the barrier performance of paper/plastic composites against hazardous substances in paper substrates is inferior to that of paper/aluminum/plastic composites. Special attention should be paid to the migration risk of AKD sizing agents when packaging high-fat or alcoholic foodstuffs. It is proposed that relevant risks can be reduced by optimizing the sizing process, strengthening the quality screening of raw paper materials, adjusting or increasing the thickness of the barrier layer and defining the application scope.

To investigate the distribution characteristics and migration rules of pesticide residues in different parts of Citrus reticulata ‘Chachi’, and establish a rapid pesticide residue detection method suitable for the matrix of Citrus reticulata ‘Chachi’.

A pesticide residue detection method combining QuEChERS pretreatment with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established and verified. This method was applied to analyze the differences in residual content of 10 kinds of common pesticides in the peel and pulp of Citrus reticulata ‘Chachi’ from 4 research bases, and detect the pesticide residue status in the whole fruit, peel and pulp from 40 actual production bases. Meanwhile, the migration capacity of the 10 kinds of pesticides was classified via K-means cluster analysis.

The established method showed a good linear relationship in the mass concentration range of 0.01–0.50 mg/L (r²≥0.99215), with the spiked recovery rate of 80.0%–110.0% and the relative standard deviation of 0.6%–6.3%. Pesticide residues in Citrus reticulata‘Chachi’ presented significant differences in different parts, and both the detected types and concentrations followed the gradient rule of “peel>whole fruit>pulp”, with the average residual concentration in peel being 2.7 times that in pulp. In addition, the migration capacity of pesticides with different chemical properties could be divided into 3 levels(high, medium and low). The pesticide residue content in the whole fruit, peel and pulp of samples from 40 actual production bases did not exceed the the limit requirements of GB 2763—2026 National food safety standard-Maximum residue limits for pesticides in food.

The QuEChERS-HPLC-MS/MS detection method established in this study is accurate and reliable, which can serve as an exclusive technical means for the detection of pesticide residues in Citrus reticulata ‘Chachi’. The clarified distribution and migration rules of pesticide residues in Citrus reticulata ‘Chachi’ provide direct scientific basis for the scientific selection and rational application of pesticides in the planting process of Citrus reticulata ‘Chachi’, and have important practical significance for the quality and safety control of the Citrus reticulata ‘Chachi’ industry.

To extract and prepare highly active hypoglycemic polysaccharides from Auricularia heimuer and evaluate their activity.

The enzymatic hydrolysis process was optimized through single-factor and orthogonal experiments to obtain the optimal α-glucosidase inhibitory activity. After deproteinization of the crude polysaccharides used the trichloromethane-n-butanol method, the polysaccharides were purified successively through a diethylaminoethyl cellulose 52 anion exchange packing column and a high-resolution sephacryl S-200 gel column. The refined Auricularia heimuer polysaccharide component (AAPS4s) was obtained.

Under the optimal conditions, the inhibition rate of crude polysaccharides on α-glucosidase was 76.38%±0.94%. The content of AAPS4s polysaccharide was 95.63%±1.46%, and the inhibitory rates against α-glucosidase and α-amylase were 72.56%±2.12% and 41.90%±0.87, respectively. The inhibitory type was mixed; the scavenging rates of 1, 1-diphenyl-2-picrylhydrazyl free radicals, hydroxyl radicals and superoxide anions were 57.39%±0.73%, 64.99%±2.65% and 38.41%±2.80%, respectively.

This study successfully obtains the highly active Auricularia heimuer polysaccharide component AAPS4s with clear activity. This component regulates digestive enzyme activity in a mixed inhibitory mode to exert in vitro hypoglycemic effects and possesses good antioxidant activity, laying a foundation for the development and industrial application of Auricularia heimuer hypoglycemic functional products.