Objective To study investigates the feasibility of accurately tracing the origin of Fragariaananassa Duch. using stable isotopes and regional characteristics of multiple elements. Methods Using stable isotope ratio mass spectrometry technology and inductively coupled plasma mass spectrometry, the stable isotope ratios of carbon (¹³C/¹²C), nitrogen (¹⁵N/¹⁴N), hydrogen (²H/¹H), and oxygen (¹⁸O/¹⁶O) and the content of 18 kinds of elements in Fragariaananassa Duch. samples was tested. The characteristic indicators of Fragariaananassa Duch. from different origins were analyzed, and stepwise discriminant analysis was used to establish 3 kinds of origin discrimination models for stable isotopes, mineral elements, and stable isotopes and mineral elements. The traceability of Fragariaananassa Duch. origins in Changping, Shuangliu, and Dandong was carried out. Results The correct discrimination rates of cross testing of 3 kinds of models were 88.4%, 90.7%, and 100.0%, respectively. Conclusion Research has shown that using a single technology for facility Fragariaananassa Duch. origin tracing and identification is not ideal, while simultaneously using stable isotope and elemental technologies for tracing can accurately distinguish the origin and provide a methodological basis for the feasibility of facility grown product origin tracing.

Objective To establish a method for the determination of advanced glycation end products (AGEs) and 5-hydroxymethylfurfural (5-HMF) in loquat fruit paste by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Methods AGEs solution was obtained by extracting loquat fruit paste with pure water and treating with ultrasonic, centrifugation, solid-phase extraction and ammonia methanol solution elution, then separated by using gradient elution with 0.1% formic acid in water and methanol as the mobile phase. The detection method employed multi-reaction monitoring with positive ion. The 5-HMF solution was obtained by extracting the fruit paste in pure water, followed a liquid-liquid extraction with ethyl acetate, solid-phase extraction and 10% methanol elution. The extracts were analyzed at 30 ℃ with 10% methanol in water as mobile phase. Results It was found that the linearity of all the targets was good in the concentration range. The limits of detection and limits of quantification of each target substance were lower than 1 [AGEs/(ng/mL); 5-HMF/(µg/mL)], which could fulfill the requirements of detecting trace substances. The relative standard deviations (RSDs) of all the substances were less than 10%, and lower than 0.6% in the range of 16 hours of sample waiting time. The recoveries of all the substances were higher than 85%. Conclusion Results indicate that the method meet the basic requirement for quantitative analysis and has good accuracy and stability, which offers a detection means of studying on quality and safety of heat-processed fruit and vegetables.

Objective To clarify the impact of gastrointestinal fluid digestion on the biological activity of Flammulina velutipes, to investigate the effect of in vitro digestion on the antioxidant activity and α-glucosidase and α-amylase inhibitory activity of Flammulina velutifolia powder. Methods In this study, Flammulina velutipes powder was simulated in vitro digestion of intestine and stomach and analyzed. With 1,1-diphenyl-2-picylhydrazyl (DPPH) free radical, OH free radical, O₂^- free radical and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS⁺) free radical, α-glucosidase and α-amylase inhibition were used as indexes to study the antioxidant activity of Flammulina velutipes powder at different digestion stages. Results After in vitro digestion, the antioxidant activity of Flammulina velutipes powder was enhanced and the free radical scavenging ability of DPPH, OH, O₂⁻ and ABTS⁺ free radical increased. The antioxidant capacity of the digested group was higher than that of the non-digested group. Its inhibitory activity against α-glucosidase and α-amylase was also enhanced and positively correlated with the concentration, and the strongest inhibitory effect on 2 kinds of enzymes was observed after intestinal digestion. Conclusion The antioxidant activity and enzyme inhibitory activity of Flammulina velutipes powder are enhanced after in vitro digestion, which indicate that the digestion process can release and enhance the bioactivity of Flammulina velutipes. However, in vitro antioxidant activity is not directly related to the actual antioxidant activity of the material. This study provides a basis for the processing and utilization of Flammulina velutipes and its activity research.

Objective To construct a reasonable pork quality evaluation system for pork grading and high quality and high price. Methods In this study, the common Dugong three-dimensional hybrid pigs were used as the control, and the longest back muscles of 7 kinds of pigs from Shanghai were collected for the determination of various indexes such as meat appearance, texture, nutrition and flavor substances, and 13 main evaluation indexes of pork quality in the real estate were determined. In order to further construct the grading standard of Shanghai real estate pork quality, factor analysis, cluster analysis and hierarchical analysis were applied to establish a comprehensive evaluation system. Results Through factor analysis, 7 indicators (moisture content, electrical conductivity, shear force, iron, fat, inosinic acid and aspartic acid) were identified as the main factors among the selected 13 indicators, and their variance contribution rate was as high as 83.829%. Using cluster analysis and chromatographic analysis, 3 different grades of scoring criteria were established according to 7 quality indicators obtained. Conclusion This study establishes a complete pork quality evaluation model and grading criteria in Shanghai, realizes the accurate control of pork quality in Shanghai, and also provides a reference for local pork quality evaluation.

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 detect mercury content in grain by direct injection method for mercury measurement.. Methods Direct injection method for mercury measurement was used to detect grain samples such as wheat, corn, and rice, and the limit of detection, accuracy, stability, and spiked recovery rate of the method were analyzed. Results When the sample size was 0.1 g, the limits of detection mercury in wheat, corn, and rice were 0.070, 0.075, 0.085 μg/kg, all of which were less than 0.2 μg/kg. The detection results of the quality control sample was 39.42 μg/kg, which was within the specified value range. The repeatability of mercury detection, with a relative standard deviation within 5%, met the stability requirements for mercury detection. The recovery rate of mercury spiked samples were 92.2%~101.4%. Conclusion Compared with traditional mercury analysis methods, direct injection method for mercury measurement has the advantages of simple operation steps, good repeatability, fast and accurate results, and is a recommended method for rapid detection of mercury content in grain.

Objective To evaluate the effect of Phyllanthus emblica L. and Lyciumbarbarum L. compound on sleep improvement in mice. Methods Balb-c mice were used as the research subjects and randomly divided into 5 groups: Control group, positive drug group, low-dose group of Phyllanthus emblica L. and Lyciumbarbarum L. compound (3.75 g/kg), medium-dose group (7.50 g/kg), and high-dose group (15.00 g/kg). Each mice received a single dose daily for 30 consecutive days. The efficacy in improving sleep in mice was assessed through direct sleep experiments, pentobarbital sodium subthreshold dose hypnosis experiments, pentobarbital sodium sleep time extension experiments, and barbiturate sodium sleep latency experiments. Additionally, the levels of 5-hydroxytryptamine (5-HT), dopamine (DA), tryptophan hydroxylase (TPH), and γ-aminobutyric acid (GABA) in the brain tissue of mice were measured using enzyme-linked immunosorbent assay colorimetric kits. Results The results showed that compared with the control group, the 3 dose groups of the combination of Phyllanthus emblica L. and Lyciumbarbarum L. compound increased the sleep rate of mice by 50%, 70%, and 90%, respectively. Additionally, all 3 dose groups significantly prolonged the pentobarbital sodium-induced sleep time in mice (P<0.01), and the high-dose group had a significantly longer sleep time than the positive drug group (P<0.01). Furthermore, the medium and high-dose groups of Phyllanthus emblica L. and Lyciumbarbarum L. compound significantly shortened the sleep latency of mice (P<0.05 or P<0.01). The measurement of neurotransmitter indicators showed that compared with the control group, the Phyllanthus emblica L. and Lyciumbarbarum L. compound, significantly increased the levels of 5-HT and GABA in the brain tissue of mice (P<0.01 or P<0.05) and significantly reduced the content of DA (P<0.01). However, it had no significant effect on the TPH content in the brain tissue of mice (P>0.05). Conclusion The Phyllanthus emblica L. and Lyciumbarbarum L. compound has a significant effect on improving sleep in mice.

Objective To prepare of Lycium barbarum and Hordeum vulgare lozenges and study of its safety quality. Methods The wolfberry and barley were ground into powder and sifted, mixed 1:1 into Lycium barbarum and Hordeum vulgare powder, kneaded into a dough with butter, and put into a grinding tool for tablet drying. The determination of toxic and harmful microorganisms and basic nutritional indexes including moisture, ash, protein, fat and starch was carried out on Lycium barbarum and Hordeum vulgare lozenges. The sensory evaluation team will score the product for sensory evaluation. Results No toxic and harmful components were detected in the lozenges of Lycium barbarum and Hordeum vulgare, and the moisture content was about 5.84%. The ash content was about 3.34%. The protein content was about 12.34%. The fat content was about 17.01%. The starch content was about 47.35%. The finished lozenge had uniform color and no special spots, complete shape without breakage, smooth taste with slight graininess, and moderate sweetness and sourness. Conclusion In this study, the utilization rate of wolfberry was improved by combining wolfberry and highland barley into lozenges, which promote the development of highland barley industry and provide a new way for wolfberry-related products.

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.

With the continuous improvement of people's consumption capacity and consumption level, baking foods are deeply loved by consumers for their rich nutrition, great taste, fashion, easy to carry and other characteristics. Baking foods often need to dehydrate the dough through high temperature and dry hot baking to dry and harden, and then chemical changes such as starch gelatinization and protein denaturation occur, and the result is delicious bread, cakes, etc. However, this kind of food would form large amounts of 5-hydroxymethylfurfural (HMF) and other pollutants during the baking process. When the content of HMF exceeded a certain limit, it would cause harm to the human body. High concentration of HMF is cytotoxic, mutagenic, genotoxic, etc., and has potential health risk to humans. How to control the formation of contaminants such as HMF in baking foods has become the focus of the food industry. This article reviewed the sources of HMF in baking foods and the toxicity of HMF, summarized the inhibition measures of HMF in baking foods in recent years from 3 aspects of improving the types of precursors in raw materials, optimizing the baking process, and adding inhibitors, to provide theoretical reference for the control of HMF in the industrial production of baking foods.