Construction of a magnetic solid-phase extraction method for the analysis of azole pesticides residue in medicinal plants.

In this work, a sensitive and cost-effective method for the quantitative analysis of azole pesticides residues in six medicinal plants was established based on magnetic cyclodextrin crosslinked with tetrafluoroterephthalonitrile (Fe3O4@TFN-CDPs) coupled with high-performance liquid chromatography (HPLC). Through characterization analysis, the outer shell of Fe3O4@TFN-CDPs has observed coating with a network of the polymer and forming a core-shell structure. Under the optimum conditions, the limits of detection (LODs) and limits of qualification (LOQs) of target pesticides were ranged from 0.011 to 0.106 µg Kg-1 and from 0.036 to 0.354 µg Kg-1, respectively. Finally, the achieved recoveries of pesticides in six medicinal samples fluctuated from 60.1% to 102.3%. Altogether, this method based on Fe3O4@TFN-CDPs composites provided a new idea for the analysis of trace pesticides in complicated matrices.

Untargeted liquid chromatography coupled with mass spectrometry reveals metabolic changes in nitrogen-deficient Isatis indigotica Fortune.

Isatis indigotica Fortune is a popular herb in traditional Chinese medicine, and various types of metabolites are the basis for its pharmacological efficacy. The biosynthesis and accumulation of these metabolites are closely linked to nitrogen availability; the benefits of low nitrogen application on the environment and herb quality are increasingly prominent. To analyze metabolic changes in the leaves and roots of I.indigotica in nitrogen deficiency conditions, and to identify the pathways and metabolites induced by low nitrogen availability, we used untargeted liquid chromatography coupled with mass spectrometry (UHPLC-TripleTOF) to obtain metabolomics profiling of I.indigotica under two N-deficiency treatments (0 kg/hm2; 337.5 kg/hm2) and normal nitrogen treatment (675 kg/hm2). A total of 447 metabolites were annotated. Principal component analysis separated the three nitrogen treatments. A greater diversity of metabolites was observed in roots than in leaves under N-deficiency treatments, suggesting that roots have a more important function in low N tolerance. Differential metabolites were mainly enriched in purine metabolism, phenylpropanoid biosynthesis, the shikimate pathway, tryptophan metabolism, and flavonoid biosynthesis that notably induced only in leaves in low nitrogen stress. Moderate N-deficiency benefits carbohydrate accumulation, whereas accumulation of most amino acids decreases. Uniquely, L-tryptophan was maintained at a high concentration in N-deficiency conditions. Low nitrogen stress induced the accumulation of some specialized metabolites (matairesinol, dictamnine, 5-hydroxyindoleacetate (serotonin) in roots and vitexin, xanthohumol, sinapyl alcohol in leaves). N-deficiency also increased the accumulation of adenosine and quality indicators of I.indigotica (indirubin-indigo, epigoitrin and anthranilic acid) in a certain degree. Our findings showed that nitrogen deficiency modified roots and leaves conditions of I.indigotica, affecting both the primary and secondary metabolism. Moderate nitrogen reduction was beneficial to the accumulation of active ingredients. Our methods and analysis are expected to provide an insight regarding the diversity of metabolites and regulation of their synthesis in low nitrogen application, and better investigate the nitrogen deficiency effect on I.indigotica.

[Effects of compound planting on growth and quality of Salvia miltiorrhiza].

The effects of four kinds of different plant populations on the morphology, the dry matter accumulation, active ingredient content and antioxidant activty in vitro of Salvia miltiorrhiza were analyzed by setting up four kinds of mixed planting groups, such as S. miltiorrhiza and Cassia obtusifolia, Capsicum annuum, Perilla frutescens and Zea mays. And through the root isolation treatment, we preliminarily explored the formation mechanism of the four kinds of matching plants of the yield and quality of S. miltiorrhiza, and chose the matching plants suitable for the establishment of the compound population with S. miltiorrhiza,and provided the basis for constructing high efficiency compound planting pattern of S. miltiorrhiza. The results showed that there were significant differences in plant morphology, dry matter accumulation of root, active ingredient content and antioxidant activty in vitro of S. miltiorrhiza in different compound population mixed. The growth and yield of S. miltiorrhiza were unfavorable to the combination planting of Cassia obtusifolia, Z. mays and Salvia miltiorrhiza.The compound planting of P. frutescens and S. miltiorrhiza significantly promoted the growth of S. miltiorrhiza, but significantly reduced the quality of S. miltiorrhiza.The yield and quality of S. miltiorrhiza were significantly improved by the combination of C. annuum and S. miltiorrhiza. Therefore, among the four plants of C. obtusifolia, C. annuum, P. frutescens, and Z. mays, the P. frutescens of Solanaceae is the best matching species for the construction of compound planting group with S. miltiorrhiza.