Variety, geographical origin, and harvest season are important factors affecting the accumulation of polyphenols in Lycium barbarum. In this study, the effects of these factors on the polyphenolic components of this species were analyzed using ultra-performance liquid chromatography ion mobility quadrupole time-of-flight mass spectrometry. Moreover, the in vitro antioxidant activities of fruit extracts from this species were evaluated. The total polyphenolic contents of L. barbarum fruits from Jinghe County in Xinjiang and Zhongning County in Ningxia were 5.52–11.72 and 7.06–9.37 mg (gallic acid equivalent)/g dry weight, while the total flavonoid contents of L. barbarum fruits from these regions were 12.52–30.29 and 12.67–20.77 mg (rutin equivalent)/g dry weight, respectively. Overall, 39 types of polyphenols were identified in the fruit extracts, including 26 flavonoids, 10 phenolic acids, and three tannins. Of these, 11 polyphenols were quantitatively analyzed, which revealed rutin to be the most dominant polyphenolic component in fruits from Jinghe and Zhongning. There were significant differences (p < 0.05) in the polyphenolic contents and antioxidant activities of L. barbarum fruit extracts, depending on the geographical origin, variety, and harvest season. The antioxidant activity of this species was found to be significantly positively correlated with the polyphenolic contents. This study provided scientific guidance for comprehensive applications of polyphenols from different varieties of L. barbarum from separate geographical origins.

Walnuts (Juglans regia L.), renowned for their nutritional potency, are a rich source of unsaturated fatty acids. Their regular intake plays a pivotal role in health maintenance and recuperation from a myriad of ailments. Fatty acyl-acyl carrier protein thioesterases, which orchestrate the hydrolysis of acyl-ACP thioester bonds, thereby yielding fatty acids of varying chain lengths, are instrumental in augmenting plant fatty acid content and modulating the balance between saturated and unsaturated fatty acids. Despite some investigative efforts into the synthesis and metabolic pathways of fatty acids in walnuts, our comprehension of Fat in walnuts remains rudimentary. This research undertook a comprehensive characterization of the JrFat family, predicated on the complete genome sequence of walnuts, leading to the identification of 8 JrFat genes and an exploration of their protein physicochemical properties. Utilizing Arabidopsis and soybean Fat genes as outgroups, JrFat genes can be categorized into 5 distinct subgroups, three of which encompass a pair of homologous gene pairs. These genes have demonstrated remarkable conservation throughout the evolutionary process, with highly analogous conserved base sequences. The promoter region of JrFats genes predominantly harbors light response and plant hormone response regulatory elements, with no discernible disparity in promoter elements among different JrFats. Predictive analyses indicate that JrFats proteins engage extensively with walnut fatty acid synthesis and metabolism-associated proteins. qRT-PCR analysis reveals an initial surge in the expression of JrFats during the development of walnut kernels, which either stabilizes or diminishes following the hard core period. Homologous gene pairs exhibit analogous expression patterns, and the expression trajectory of JrFats aligns with the dynamic accumulation of fatty acids in kernels. The expression of JrFatA2 exhibits a strong correlation with the content of Alpha-linolenic acid, while the expression of JrFatB2 is inversely correlated with the content of two saturated fatty acids. Collectively, these findings enrich our understanding of fatty acid synthesis and metabolism in walnuts and furnish gene resources for enhancing the content and ratio of fatty acids in walnuts.

Molecularly imprinted polymers (MIPs) that had high selectivity for five pyrethroid pesticides with high detection and exceedance rates were synthesized through precipitation polymerization using ethyl chrysanthemate and phenyl ether-biphenyl eutectic mixture as double template molecules, acrylamide as a functional monomer, ethylene glycol dimethacrylate as a crosslinking agent, and acetonitrile as a porogen. The imprinted polymers prepared were then characterized and evaluated through scanning electron microscopy (SEM) and an equilibrium adsorption experiment. The results showed that the MIPs had specific adsorption capacities for five pyrethroid pesticides. A solidphase extraction column was prepared using the synthesized polymers as the adsorption material, and a molecularly imprinted solid-phase extraction-gas chromatography equipped with an electron capture detector (MI-SPE-GC-ECD) method was confirmed for the determination of five pyrethroid pesticide residues in agricultural products. A good linear relationship was present between the peak area and the concentration of pyrethroid insecticides within the range of 2-100 μg/kg. The correlation coefficient (R2) was greater than 0.9930, and the minimum limits of detection and quantification were 15.5-25.8 and 54.3-88.1 ng/L, respectively. Under different levels of additives, the standard recovery of pyrethroid pesticides in the samples varied from 72.8% to 110.2%, and the relative standard deviation (RSD) was less than 5.5%. In conclusion, this method enables the rapid separation and efficient enrichment of multiple pyrethroid pesticides in agricultural products in a single step.