Persulfate promoted visible photocatalytic elimination of bisphenol A by g-C3N4-CeO2 S-scheme heterojunction: The dominant role of photo-induced holes.

In the last few years, coupling heterogeneous photocatalysis with persulfate (PDS) activation process is an efficient approach to generate abundant reactive oxidative species towards organic contaminant removal in water, however, the key role of PDS in photocatalytic process remains ambiguous. Herein, a novel g-C3N4-CeO2 (CN-CeO2) step-scheme (S-scheme) composite was constructed to photo-degrade bisphenol A (BPA) with the presence of PDS under visible irradiation. At 2.0 mM PDS, 0.7 g/L CN-CeO2 and natural pH 6.2, 94.2% of BPA could be eliminated in 60 min under visible light (Vis) illumination. Aside from the previous view of free radical generation, it tends to assume that most of PDS molecules acted as electron sacrificial agents for capturing photo-induced e- to form sulfate ions, greatly improving the charge carrier separation and thus enhancing the oxidation capacity of nonradical hole (h+) for the removal of BPA. Good correlations are further found between the rate constant and descriptor variables (i.e., Hammett constant σ-/σ+ and half-wave potential E1/2), exhibiting selective oxidation for organic pollutants in the Vis/CN-CeO2/PDS system. The study brings more insights into mechanistic understanding of persulfate-enhanced photocatalytic process for addressing water decontamination.

Systems Pharmacology Uncovers Multiple Mechanisms of Erxian Decoction () for Treatment of Premature Ovarian Failure.

OBJECTIVE: To predict the chemical compositions and drug targets and to systematically dissect the pharmacological mechanism of Erxian Decoction (, EXD) as a treatment for premature ovarian failure (POF) using a systems pharmacology approach. METHODS: The compounds present in EXD were obtained from three databases. The active ingredient was identified by analyzing the values of oral bioavailability (OB), drug-likeness (DL), and Lipinski's rule (LR). The active ingredients were further searched in research articles, drug targets in the DrugBank database, and the C-T and T-P networks, as well as by pathway analysis using the Cytoscape platform. RESULTS: A total of 728 compounds were identified in EXD. Of these, 59 were identified as active compounds that conformed to the criteria with OB ⩾30% and DL ⩾0.18. By further searches in the literature, 126 related targets were identified that could interact with the active compounds. Additionally, it was found that the beneficial effects of EXD in POF are probably exerted via regulation of the immune system, modulation of estrogen levels, and anti-oxidative activities, and that it may act in a synergistic or cooperative manner with other therapeutic agents. CONCLUSIONS: The systems pharmacology approach is a comprehensive system that was used to elucidate the pharmacological mechanism of EXD as a treatment for POF. The results of this study will also facilitate the application of traditional medicine in modern treatment strategies.