Synthesis and fungicidal activity of phenazine-1-carboxylic triazole derivatives.

A total of 15 novel-substituted 3-(benzylsulfanyl)-1H-1,2,4-triazol-5-ylamine and 10 novel-substituted 3-benzylmercapto-1,2,4-triazol derivatives were synthesized based on the natural product phenazine-1-carboxylic acid (PCA). Their structures were confirmed by 1H-NMR, 13C-NMR, HRMS, and X-ray. Most substituted 3-benzylmercapto-1,2,4-triazol derivatives displayed very strong fungicidal activity against one or multiple plant pathogens in vitro and in vivo. Compounds 8b, 8h, and 8i showed a broad spectrum of fungicidal activity. Further field experiments indicated that compounds 8b, 8c, and 8h displayed better efficacy against rice blast (Pyricularia oryzae) than PCA. These data demonstrate that compounds 8b, 8c, and 8h are promising fungicidal candidates, deserving further studies.[Formula: see text].

Synthesis and antifungal evaluation of PCA amide analogues.

To improve the physical and chemical properties of phenazine-1-carboxylic acid (PCA) and find higher antifungal compounds, a series of PCA amide analogues were designed and synthesized and their structures were confirmed by 1H NMR, HRMS, and X-ray. Most compounds showed some antifungal activities in vitro. Particularly, compound 3d exhibited inhibition effect against Pyriculariaoryzac Cavgra with EC50 value of 28.7 µM and compound 3q exhibited effect against Rhizoctonia solani with EC50 value of 24.5 µM, more potently active than that of the positive control PCA with its EC50 values of 37.3 µM (Pyriculariaoryzac Cavgra) and 33.2 µM (Rhizoctonia solani), respectively.

[Inhibitory effect of Panax notoginseng saponins on alveolar epithelial to mesenchymal transition].

In the study, the effects of Panax notoginseng saponins (PNS) on alveolar epithelial to mesenchymal transition (EMT) and extracellular matrix degradation were observed in a type of human alveolar epithelial cell, A549 cells, stimulated by TGF-beta1. Firstly, MTT method was applied to evaluation of cellular proliferation and found that PNS from 12.5 mg x L(-1) to 200 mg x L(-1) dosage could not inhibit significantly cellular proliferation. Then, cells were divided into five groups, normal group, TGF-beta1 group, TGF-beta1 + 50 mg x L(-1) PNS group, TGF-beta1 + 100 mg x L(-1) PNS group and TGF-beta1 + 200 mg x L(-1) PNS group. Normal cells were not stimulatec by TGF-beta1; TGF-beta1 cells were only stimulated by TGF-beta1 and the other cells were stimulated by TGF-beta1 with different doses of PNS, respectively. After stimulation, cells and supernatants were collected for assays. Cellular roundness was applied to quantitative evaluation of morphological change. Immunocytochemistry was applied to examine E-cadherion, a-SMA and FN proteins expression in the cells. Enzyme linked-immunosorbent assay was applied to MMP-9 and TIMP-1 levels. The results showed that EMT of A549 cells was induced by TGF-beta1, showing significant change of roundness, E-cadherion, alpha-SMA and FN (P < 0.05, P < 0.01). Compared to TGF-beta1, PNS significantly inhibited the changes of roundness (P < 0.05), FN and alpha-SMA (P < 0.05, P < 0.01) and not significantly inhibited the change of E-cadherion. Furthermore, MMP-9 levels were significantly increased by TGFbeta1 stimulation (P < 0.05), without significant change of TIMP-1. Compared with TGF-beta1, PNS could significantly increase MMP-9 level (P < 0.05) and decrease TIMP-1 levels (P < 0.05, P < 0.01). In conclusion, PNS could inhibit alveolar epithelial cell EMT induced by TGF-beta1, with increase of extracellular matrix degradation ability, which showed anti-fibrosis of lung ability.

Genetic evidence for a causal link between gut microbiota and arterial embolism and thrombosis: a two-sample Mendelian randomization study.

Background: Previous research has hinted at a crucial link between gut microbiota and arterial embolism and thrombosis, yet the causal relationship remains enigmatic. To gain a deeper understanding, we aimed to comprehensively explore the causal relationship and elucidate the impact of the gut microbiota on the risk through a two-sample Mendelian randomization (MR) study. Methods: Genetic instrumental variables for gut microbiota were identified from a genome-wide association study (GWAS) of 18,340 participants. Summary statistics for IBS were drawn from a GWAS including 1,076 cases and 381,997 controls. We used the inverse-variance weighted (IVW) method as the primary analysis. To test the robustness of our results, we further performed the weighted median method, MR-Egger regression, and MR pleiotropy residual sum and outlier test. Results: We identified three bacterial traits that were associated with the risk of arterial embolism and thrombosis: odds ratio (OR): 1.58, 95% confidence interval (CI): 1.08-2.31, p = 0.017 for genus Catenibacterium; OR: 0.64, 95% CI: 0.42-0.96, p = 0.031 for genus Dialister; and OR: 2.08, 95% CI: 1.25-3.47, p = 0.005 for genus Odoribacter. The results of sensitivity analyses for these bacterial traits were consistent (P<0.05). Conclusion: Our systematic analyses provided evidence to support a potential causal relationship between several gut microbiota taxa and the risk of arterial embolism and thrombosis. More studies are required to show how the gut microbiota affects the development of arterial embolism and thrombosis.

Chemical Constituents from Fraxinus hupehensis and Their Antifungal and Herbicidal Activities.

The phytochemical investigation of Fraxinus hupehensis led to the isolation and characterization of ten compounds which were identified as fraxin (1), fraxetin (2), esculetin (3), cichoriin (4), euphorbetin (5), kaempferol-3-O-ß-rutinoside (6), oleuropein (7), linoleic acid (8), methyl linoleate (9), and ß-sitosterol (10). Structures of the isolated constituents were characterized by 1H NMR, 13C NMR and HRMS. All the compounds, except compounds 3 and 4, were isolated for the first time from this plant. Further, this was the first report for the occurrence of compound 5 in the Fraxinus species. Antifungal activity evaluation showed that compound 2 exhibited significant inhibitory effects against Bipolaris maydis, Sclerotium rolfsii, and Alternaria solani with EC50 values of 0.31 ± 0.01 mmol/L, 10.50 ± 0.02 mmol/L, and 0.40 ± 0.02 mmol/L respectively, compared to the positive control, Carbendazim, with its EC50 values of 0.74 ± 0.01 mmol/L, 1.78 ± 0.01 mmol/L and 1.41 ± 0.00 mmol/L. Herbicidal activity tests showed that compounds 8-10 had strong inhibitory effects against the roots of Echinochloa crus-galli with EC50 values of 1.16 ± 0.23 mmol/L, 1.28 ± 0.58 mmol/L and 1.33 ± 0.35 mmol/L respectively, more potently active than that of the positive control, Cyanazine, with its EC50 values of 1.56 ± 0.44 mmol/L. However, none of the compounds proved to be active against the tested bacteria (Erwinia carotovora, Pseudomonas syringae, and Ralstonia solanacearum).

[Assessment of Heavy Metal Pollution in Soil and Its Bioaccumulation by Dominant Plants in a Lead-Zinc Mining Area, Nanjing].

To identify plants with potential application in phytoremediation, the concentration of cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), lead (Pb), and zinc (Zn) in soil and 14 dominant plants sampled from a lead-zinc mining area in Nanjing City was measured. Furthermore, the heavy metal contamination of soil, and bioaccumulation and translocation of the 6 heavy metals by the 14 plants were evaluated. The results showed that the principal contaminants were Cd, Mn, Zn, and Pb, and their single factor pollution index was 45.71, 11.68, 10.40, and 4.46, respectively. Furthermore, the Nemerow index of this area was 33.45, which indicated that the mining area was severely polluted. All the 14 dominant plant species were metal-tolerant, although the concentration of metal varied between different spices. Among them, Pteris multifida and Trachelospermum jasminoides significantly accumulated the heavy metals. The concentration of Zn in all the dominant plants was beyond the normal range; however, the bio-concentration factor (BCF) of only Digitaria sanguinalis for Zn was>1, while the BCF of the remaining species for the 6 heavy metals was<1. Furthermore, the heavy metal bio-transfer factor (BTF) of the 14 species was generally high. The BTF of Helianthus tuberosus and Dendranthema indicum for the 6 heavy metals was>1. According to the mechanism of heavy metal accumulation, the 14 plant species were classified into 3 types:accumulators (H. tuberosus, D. indicum, Phytolacca americana, Justicia procumbens, D. sanguinalis, Sonchus brachyotus, Solanum nigrum, and Setaria viridis), root compartment (P. multifida and T. jasminoides), and excluders (Solidago decurrens, Duchesnea indica, Carex breviculmis, and Cyrtomium fortunei).

Volatiles released by Chinese liquorice roots mediate host location behaviour by neonate Porphyrophora sophorae (Hemiptera: Margarodidae).

BACKGROUND: The cochineal scale, Porphyrophora sophorae (Hemiptera: Coccoidea, Margarodidae), is one of the most serious arthropod pests of Chinese liquorice, Glycyrrhiza uralensis (Fabaceae), an important medicinal herb. The adult females tend to deposit the ovisacs in soil relatively far away from liquorice plants. After hatching, neonates move out of the soil and may use chemical cues to search for new hosts. RESULTS: We collected and analysed the volatiles from soils with and without liquorice roots, and chromatographic profiles revealed hexanal, ß-pinene and hexanol as potential host-finding cues for P. sphorae. The attractiveness of these compounds to neonates was studied in the laboratory using four-arm olfactometer bioassays. The larvae showed a clear preference for ß-pinene over hexanal and hexanol, as well as all possible combinations of the three compounds. In addition, a field experiment confirmed that ß-pinene was significantly more attractive than hexanal and hexanol. CONCLUSION: Newly eclosed larvae of P. sphorae exploit root volatiles as chemical cues to locate their host plant. ß-Pinene proved to be the major chemical cue used by P. sphorae neonates searching for roots of their host plant. © 2016 Society of Chemical Industry.

Novel polymer monolith microextraction using a poly-(methyl methacrylate-co-ethylene dimethacrylate) monolith and its application to the determination of polychlorinated biphenyls in water samples.

A novel and simple method based on polymer monolith microextraction (PMME) coupled to gas chromatography with electron-capture detection (GC-ECD) was developed for the determination of six polychlorinated biphenyls (PCBs) residues in water samples. The proposed method used poly-(methyl methacrylate-co-ethylene dimethacrylate) (MMA-co-EDMA) monolith as extraction media. Several factors affecting experiments such as sample flow rate, sample volume, the type of eluent, eluent volume, eluent flow rate, effect of salt addition and carry over effect were investigated and optimized systematically. The limits of detection (LODs) for six PCBs were 0.028-0.043 ng mL(-1) in water samples. The intra-day and inter-day precisions (R.S.D.) were less than 9.2% and 9.6%, respectively. The proposed method was successfully applied to the determination of six PCBs in tap water, lake water and industrial waste water and the trueness has been evaluated by recovery experiments. The obtained relative recoveries were in the range of 63.3-105.6%.

Dispersive liquid-liquid microextraction based on the solidification of floating organic droplet for the determination of polychlorinated biphenyls in aqueous samples.

In the proposed method, an extraction solvent with a lower toxicity and density than the solvents typically used in dispersive liquid-liquid microextraction was used to extract seven polychlorinated biphenyls (PCBs) from aqueous samples. Due to the density and melting point of the extraction solvent, the extract which forms a layer on top of aqueous sample can be collected by solidifying it at low temperatures, which form a layer on top of the aqueous sample. Furthermore, the solidified phase can be easily removed from the aqueous phase. Based on preliminary studies, 1-undecanol was selected as the extraction solvent, and a series of parameters that affect the extraction efficiency were systematically investigated. Under the optimized conditions, enrichment factors for PCBs ranged between 494 and 606. Based on a signal-to-noise ratio of 3, the limit of detection for the method ranged between 3.3 and 5.4 ng L(-1). Good linearity, reproducibility and recovery were also obtained.