Developmental effects and lipid disturbances of zebrafish embryos exposed to three newly recognized bisphenol A analogues.

Bisphenol G (BPG), bisphenol M (BPM) and bisphenol TMC (BPTMC), are newly recognized analogues of bisphenol A (BPA), which have been detected in multiple environmental media. However, the understanding of their negative impacts on environmental health is limited. In this study, zebrafish embryos were exposed to BPA and the three analogues (0.1, 10, and 1000 µg/L) to identify their developmental toxic effects. According to our results, all of the three analogues induced significant developmental disorders on zebrafish embryos including inhibited yolk sac absorption, altered heart rate, and teratogenic effects. Oil Red O staining indicated lipid accumulation in the yolk sac region of zebrafish after bisphenol analogues exposure, which was consistent with the delayed yolk uptake. Untargeted lipidomic analysis indicated the abundance of triacylglycerols, ceramides and fatty acids was significantly altered by the three analogues. The combined analysis of lipidomics and transcriptomics results indicated BPG and BPM affected lipid metabolism by disrupting peroxisome proliferator-activated receptor pathway and interfering with lipid homeostasis and transport. This partly explained the morphological changes of embryos after bisphenol exposure. In conclusion, our study reveals that BPG, BPM and BPTMC possess acute and developmental toxicity toward zebrafish, and the developmental abnormalities are associated with the disturbances in lipid metabolism.

Synthesis of MoO3- x nanosheets and its application in ascorbic acid detection of fruit and vegetables.

A new method combining ultraviolet (UV) spectrophotometry and MoO3- x nanosheets was developed for the rapid and accurate determination of ascorbic acid (AA) content in fruit and vegetables in this study. MoO3- x nanosheets were prepared by the liquid exfoliation method using AA as the reducing agent, and the content of AA can be determined by a UV spectrophotometer. Experimental conditions for the MoO3- x nanosheet method, including grinding time, ethanol concentration, sonication time, and water bath temperature were also optimized. The morphology of MoO3- x nanosheets was characterized by atomic force microscope. The results showed that the average thickness of MoO3- x nanosheets was 2.1-5.8 nm. The MoO3- x nanosheets method had a good linearity in the AA concentration range of 0.01-0.05 mg/ml (R2  = 0.9996). The limit of detection was 0.031 µg/ml, and the limit of quantitation was 0.095 µg/ml. The spiked recoveries were in the range of 88.79%-116.76%. The MoO3- x nanosheets method was validated for the determination of AA content in five different fruit and vegetables samples with relative standard deviations less than 2%.

Analysis of Nutrients and Volatile Compounds in Cherry Tomatoes Stored at Different Temperatures.

Monitoring of the quality change of cherry tomatoes during storage is very important for the quality control of cherry tomatoes. In this study, the soluble solids content (SSC), reducing sugars (RSs), titratable acids (TAs), ascorbic acid (AA) and lycopene of cherry tomatoes during storage at 0, 4, 10 or 25 °C were measured, and the kinetic models were established. The results showed that the zero-order reaction combined with the Arrhenius kinetic model could be used for the prediction of changes in SS, RS and AA content. The first-order reaction combined with the Arrhenius kinetic model could be used for the prediction of changes in the TA and lycopene content. The volatile compounds of cherry tomatoes were simultaneously determined by the gas chromatography-mass spectrometry (GC-MS) and electronic nose (E-nose). A total of 104 volatile compounds were identified by GC-MS. Orthogonal partial least squares discriminant analysis (OPLS-DA) showed that there were 13 different metabolites among cherry tomatoes with different freshness. The accuracies of Fisher's models based on E-nose for discriminating freshness of cherry tomatoes stored at 0, 4, 10 and 25 °C were 96%, 100%, 92% and 90%, respectively. This study provides a theoretical basis for the quality control of cherry tomatoes during storage.