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The present study aimed to investigate bio-function, focusing the on antioxidant, bactericidal, and matrix metalloproteinase (MMP) regulatory activity, of food-related plants. Bioassay-coupled chromatography and bioassay guiding, the rapid and simple screening method, was used to identify potential antioxidant and bactericidal components from fifty-five food-related plants. Lonicera japonica exhibited moderate xanthine oxidase (XO) inhibition and antioxidant activity. Rhodiola rosea, provoked strongly inhibition for tyrosinase, lipoxygenase (LOX), XO and MMP-2 activity. The organic fractions of Ligusticum sinense had a significant antimicrobial effect against two Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa) and two Gram-positive species (Staphylococcus aureus, and Bacillus subtilis). The chemical structures of MMP-2-inhibiting and antimicrobial components was further identified as 1,2,3,4,6-penta-O-galloyl-β- d -glucopyranoside and ferulic acid, respectively, which were determined by 1H and 13C nuclear magnetic resonance (NMR) and mass spectrometry (MS). The results suggest that R. rosea and L. sinense could be a useful natural food preservatives and potential nutraceutical ingredients.

Dicrotophos (Dic), an insecticide and acaricide, is used against a variety of sucking, boring and chewing pests. It was proven that Dic induced oxidative DNA damage in HepG2 cells. However, the molecular mechanisms of this compound were still unclear. First of all, the cytotoxicity and oxidative DNA damage were confirmed. Next, using RNA-seq for detecting differential expressed genes (DEGs) in cells treated with 50 μM Dic for 24 h, we showed that the dysregulation of these genes, irrespective of up (1298 genes) or down (2125 genes) regulation, could be attributed to some diverse pathways/metabolisms using KEGG analysis, particularly in DNA damage responses (DDRs) such as oxidative phosphorylation, nucleotide excision repair and cell cycle arrest. Validation of some randomly selected DDR genes confirmed RNA-seq results. We further demonstrated that Dic induced ROS overproduction, the loss of mitochondrial depolarization and cell cycle arrest in the G0/G1 phase. In addition, we also definitely clarified the role of CSA, a nucleotide excision repair enzymes in Dic-treated cells. Collectively, our results showed that various mechanisms of Dic-induced toxicity in HepG2 cells including downregulation of some genes related to nucleotide excision repair including CSA and increased oxidative stress.

This study investigates the nonlinear optical properties of azo-dye-doped nematic and polymer-dispersed liquid crystal (ADDPDLC) films with nano-sized LC droplets using the Z-scan technique, which is a simple but powerful technique for measuring the optical Kerr constants of materials. The results indicate that the optical Kerr constant ( n 2 ) of the azo-dye-doped nematic LC (ADDLC) film is large because of the photoisomerization effect and the thermal effect. Therefore, the optical Kerr constant of this material can be modulated by varying the temperature of the sample and the direction of polarization of incident laser. The range of n 2 modulated is from −5.26 × 10 −3 to 1.62 × 10 −3 cm 2 /W. The optical Kerr constants of ADDPDLC films at various temperatures are also measured. The experimental results reveal that liquid crystals in the ADDPDLC film strengthen the nonlinearity. The n 2 of the ADDPDLC film is maximal at ∼35 °C, because of the decrease in the clearing temperature of the ADDPDLC films. The clearing temperatures of the liquid crystals (E7), and the ADDPDLC film used in this work were found to be 61 °C and 43 °C, respectively.