The chemical insecticide flonicamid is widely used to control aphids on crops. Differences among crops make the universality of detection methods a particularly important consideration. The aim of this study was to establish a universal, sensitive, accurate and efficient method for the determination of flonicamid residues in peach, cucumber, cabbage and cotton. QuEChERS pretreatment was combined with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). A satisfactory recovery rate of 84.3–99.3% was achieved at three spiking levels, and the relative standard deviation (RSD) was 0.41–5.95%. The limit of quantification (LOQ) of flonicamid in the four matrices was 0.01 mg/kg. The residue and dissipation kinetics of flonicamid in four types of crops in various locations were determined by using the optimized method. The results showed that flonicamid had a high dissipation rate in the four different types of crops and a half-life in the different matrices and locations of 2.28–9.74 days. The terminal residue of flonicamid was lower than the maximum residue limit (MRL). The risk quotient (RQ) of flonicamid was 4.4%, which is significantly lower than 100%. This result shows that the dietary risk presented by using flonicamid at the maximum recommended dose is low and acceptable. The comprehensive long-term dietary risk assessment of flonicamid performed in this study provides a reference for the protection of consumer health and safe insecticide use.

Wolfberry (Lycium barbarum L.) is a small Solanaceae shrub with medicinal and edible homology, and widely used as ethnobotanical medicine and nutraceutical food. The wolfberry fruits mainly have red, purple, and yellow phenotypes. Wolfberries are rich in flavonoids, which are natural water-soluble pigments that endow a variety of colors in plants There are very few investigations on mechanism of flavonoids biosynthesis and fruit coloring reported about wolfberry. The widely targeted metabolome and transcriptome analysis were performed to obtain metabolite and gene expression profiles of red, yellow, and purple wolfberries and to explain the underlying molecular mechanism of the color differences in wolfberry. As result, metabolomics analysis revealed that the bluish anthocyanins Malvidin and petunidin trended to accumulate in purple wolf-berry, while red and yellow wolfberries trended to accumulate more yellowish flavonoids. And transcriptome analysis showed that flavonoid synthesis-related genes, such as CHS, F3H, ANS and DFR, and several MYB and bHLH genes were differentially expressed among wolfberries in different colors: most of them were more highly expressed in purple wolfberries than in red and yellow ones. In conclusion, the different flavonoids’ accumulation patterns may result in the different fruit colors of wolfberry, and the MYB or bHLH transcription factors could regulate the expression of flavonoids biosynthesis related genes to change the composition of flavonoids or anthocyanins in wolfberry fruits and result in varied fruit colors. These findings provide new insights into the underlying molecular mechanism of the fruit color differences in wolfberry and provide new ideas for molecular breeding of wolfberry.

Lycium barbarum L. (goji berry), a traditional Chinese medicinal plant, depends heavily on nitrogen input to maintain productivity. Nitrogen application also profoundly influences rhizosphere microbial dynamics, which are critical for soil health and plant performance. This study aimed to investigate how the rhizosphere fungal community responds to nitrogen input and explore the potential role of beneficial fungi (e.g., Chaetomium) in goji berry rhizosphere enrichment. A field experiment with four nitrogen levels (0, 53.82, 67.62, and 80.73 g·N m⁻²·year⁻¹, designated as N0, N1, N2, and N3) was conducted to analyze the fungal community structure in the rhizosphere of goji berry using ITS rRNA gene amplicon sequencing. The results showed that nitrogen input significantly altered the rhizosphere fungal community composition and diversity. Redundancy analysis (RDA) and Mantel tests indicated that soil electrical conductivity, total phosphorus, available phosphorus, and nitrate nitrogen were key environmental factors driving the fungal communities’ shifts. Notably, specific fungal genera, including Chaetomium, Cladosporium, Gibberella, Fusarium, Pyxidiophora, Acaulium, and Lophotrichus, exhibited differential enrichment across nitrogen levels. In particular, Chaetomium was significantly enriched under the conventional nitrogen treatment (N2), a strain of Chaetomium sp. LC101 was successfully isolated from the goji berry rhizosphere, and its functional roles were verified via pot experiments. Inoculation with Chaetomium sp. LC101 significantly promoted goji berry growth, with the most pronounced effects observed under N0 treatments, root fresh weight, root vitality, and leaf chlorophyll content increased by up to 55.10%, 15.69%, and 43.27%, respectively, compared to non-inoculated controls. Additionally, Chaetomium sp. LC101 regulated rhizosphere nitrogen transformation by enhancing urease, nitrite reductase, and polyphenol oxidase activities while inhibiting nitrate reductase activity. These findings demonstrate that Chaetomium responds sensitively to nitrogen input, with enrichment under moderate nitrogen levels, and acts as a beneficial rhizosphere fungus by promoting plant growth and regulating nitrogen cycling. This study provides novel insights for nitrogen management in the goji berry industry, where synergistic regulation via “nitrogen reduction combined with microbial inoculation” can reduce nitrogen loss, improve yield and quality through functional fungi, and contribute to ecological sustainability.

Polysaccharides have attracted extensive attention due to their pharmacological activities, such as regulating depression, antitumor, hypoglycemic and lipid-lowering effects, and regulating intestinal flora. In this study, four crude polysaccharide fractions were separated and prepared from Lycium barbarum L., named LICP007, LICP008, LICP009 and LICP010. With hypoglycemic activity in vitro, LICP007 with a better hypoglycemic effect was selected for further separation and purification, and one neutral polysaccharide (LICP007-N1) and two acidic polysaccharides (LICP007-S2 and LICP007-S5) were obtained by DEAE-52 and Sephadex G-200 gel electrophoresis. Among them, LICP007-S5 showed the best inhibitory activity against α-amylase and α-glucosidase. Studies on physical and chemical properties show that LICP007-S5 was indeed very different from LICP007-N1 and LICP007-S2 in molecular weight distribution, monosaccharide composition, morphology and so on. These findings provide comparative information on the structure and biological activity of different Lycium barbarum polysaccharides and highlight their potential as hypoglycemic agents in functional foods.

Polysaccharides have attracted extensive attention due to their pharmacological activities, such as regulating depression, antitumor, hypoglycemic and lipid-lowering effects, and regulating intestinal flora. In this study, four crude polysaccharide fractions, designated LICP007, LICP008, LICP009 and LICP010, were prepared from Lycium barbarum L. Based on the in vitro α-amylase and α-glucosidase inhibitory assays, LICP007, which showed the strongest activity among the four crude polysaccharides (inhibition rates of 61.42 ± 0.29% against α-amylase and 40.69 ± 0.35% against α-glucosidase at 50 mg/mL), was selected for further separation and purification, and one neutral polysaccharide (LICP007-N1) and two acidic polysaccharides (LICP007-S2 and LICP007-S5) were obtained by DEAE-52 cellulose anion-exchange and Sephadex G-200 gel permeation chromatography. Among them, LICP007-S5 showed the best inhibitory activity against α-amylase and α-glucosidase, with inhibition rates of 98.38% and 43.45% at 20 mg/mL, respectively. Physicochemical characterization showed that LICP007-S5 differed markedly from LICP007-N1 and LICP007-S2 in molecular weight distribution, monosaccharide composition and morphology. Structural analysis indicated that LICP007-S5 is an acidic heteropolysaccharide rich in galacturonic acid (27.5 mol%); atomic force microscopy (AFM) and Congo red test results suggest that it may adopt an ordered, possibly triple-helical conformation, although this requires further verification. These findings provide comparative information on the structure and biological activity of different Lycium barbarum polysaccharides and highlight their potential as natural α-amylase and α-glucosidase inhibitors for the dietary management of type 2 diabetes in functional foods.