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Background: As a traditional Chinese herbal medicine, Paeonia lactiflora Pall is rich in various active ingredients such as polysaccharides and total flavonoids while having ornamental value. It has potential application value in the development of food and cosmetics. Objective: To study the in vitro efficacy of Paeonia lactiflora Pall seeds oil. Methods: Firstly, the levels of linolenic acid and linoleic acid in Paeonia lactiflora Pall seeds oil were quantified using gas chromatography. The impact of Paeonia lactiflora Pall seeds oil on the proliferation rate of B16F10 cells was assessed through the CCK‐8 method, while the melanin content of B16F10 cells was determined using the sodium hydroxide lysis method. The inhibitory effects of Paeonia lactiflora Pall seeds oil on elastase, collagenase and hyaluronidase were evaluated by biochemical techniques in vitro. Lastly, the hen's egg chorioallantoic membrane test (HET‐CAM) was conducted to confirm the absence of eye irritation caused by Paeonia lactiflora Pall seeds oil. Results: Paeonia lactiflora Pall seeds oil within a certain volume concentration range (0.5%–4%) had no effect on the proliferation of B16F10 cells. Paeonia lactiflora Pall seeds oil showed significant inhibition of elastase, collagenase and hyaluronidase. Notably, the highest concentration tested, 4% Paeonia lactiflora Pall seed oil, yielded the most pronounced outcomes without causing any irritation. Conclusion: A certain concentration of Paeonia lactiflora Pall seeds oil has a significant effect on decreasing the melanin content in B16F10 cells and inhibiting the activities of elastase, collagenase, and hyaluronidase, which can provide a reference for the development of pure natural cosmetics raw materials. [ABSTRACT FROM AUTHOR]

Background: Increasing amounts of ultraviolet radiation occur as ozone depletion causes the earth's ozone layer to be destroyed, making antioxidant efficacy a research hotspot. Previous studies on plum blossom have mostly focused on Volatile Oils, Flavonoids, Phenylpropanoids, and other compounds, whereas few studies have focused on low molecular weight polypeptide (LMWP) of plum blossom. This research provides a reference for the deep processing and utilization of plum blossom. Objectives: (a) Plum blossom low molecular weight polypeptides protect HaCaT cells against UVB‐induced oxidative damage in vitro and the underlying mechanism. (b) Improve the theoretical basis for the intense processing and utilization of plum blossom. Methods: The safe concentration of LMWP and the survival rate of HaCaT cells were determined using the CCK‐8 experiment. The fluorescence intensity of reactive oxygen species (ROS) was identified using the dichlorofluorescin diacetate (DCFH‐DA) method; Superoxide dismutase (SOD) and malondialdehyde (MDA) concentrations were measured in ruptured cells; Western blot analysis was used to examine the expression levels of three proteins: nuclear factor E2‐related factor 2 (Nrf2), heme oxygenase 1 (HO‐1), and benzoquinone oxidoreductase 1 (NQO‐1). Results: It was noted that a certain concentration of LMWP could promote cell proliferation. In oxidatively damaged HaCaT cells, SOD levels and survival rates were markedly reduced, but ROS and MDA levels were elevated. However, after treatment with LMWP, the survival rate of the cells and SOD levels were markedly increased, and the levels of ROS and MDA were markedly decreased. As shown by Western blotting, the model group exhibited lower levels of Nrf2, HO‐1, and NQO‐1 expression than the control group, whereas LMWP‐treated cells had significantly higher levels of Nrf2, HO‐1, and NQO‐1 expression than their model‐treated counterparts. Conclusions: LMMP can effectively protect HaCaT cells against oxidative damage in vitro induced by UVB, and the underlying mechanism is linked to the activation of the transcription factor Nrf2. [ABSTRACT FROM AUTHOR]

C4F7N/CO2 mixture has been widely studied as an environmental-friendly insulating gas expected to replace sulfur hexafluoride (SF6) in high-voltage equipment. In high-voltage power systems, the medium dielectric characteristics under switching impulse (SI) voltage are an important factor in insulation coordination. Nevertheless, few studies on this aspect of C4F7N/CO2 mixture have been reported. This article investigates the surface flashover of a cylindrical insulator in a C4F7N/CO2 mixture under switching voltage. The effects of molar fraction, gas pressure, creepage distance, and insulator materials on surface flashover voltage are studied in a uniform field. The result shows that the increase of flashover voltage indicates a saturation trend with the increase of C4F7N molar fraction and pressure, respectively. The dielectric strength of 13% C4F7N/87% CO2 relative to SF6 can reach at least 84%. The limiting factors of the flashover voltage increase under high pressure are preliminarily discussed. Additionally, the empirical formula on the critical flashover electrical field has been obtained, which can provide a reference for insulation design for environment-friendly gas insulation equipment. [ABSTRACT FROM AUTHOR]