In this study, a novel nanofiber material possessing antibacterial and antioxidant properties was fabricated through coaxial electrospinning, utilizing polylactic acid (PLA), thymol (THY), and nano zinc oxide (ZnO) as the raw materials. THY and ZnO was used to endows the membranes with good antibacterial and antioxidant properties. The surface morphology of the PLA/Z@T nanofiber membrane was characterized using scanning electron microscopy (SEM). Additionally, the successful formation of the core-shell structure was verified through transmission electron microscopy (TEM), fluorescence microscopy, and Fourier transform infrared spectroscopy (FTIR). Additionally, both ZnO and THY exhibit strong antibacterial properties, and their synergistic effect significantly enhances the antibacterial activity of the composite nanofiber membranes against Staphylococcus aureus . The drug sustained release percentages within 24 h for PLA@T and PLA/Z@T were 15.91 % and 14.82 %, respectively. The addition of zinc oxide does not significantly affect the release efficiency of thymol. After continuous release for 288 h, these percentages increased to 73.35 % and 72.94 %, respectively. By assessing antioxidant activity through DPPH and ABTS assays, it was found that PLA/Z@T exhibited higher activity compared to the control group. Subsequently, the in vitro antibacterial performance was investigated, revealing an antibacterial rate higher than that of the control group, the antibacterial rates against Staphylococcus and Escherichia coli reached 99.75 % and 98.49 % respectively. In conclusion, the results demonstrate that PLA/Z@T nanofiber membranes possess excellent antibacterial efficiency, sustained antibacterial performance, and antioxidant properties, offering a novel strategy for antibacterial materials.
Mei Yang,Minzhen Yin,Shanshan Chu,Yujiao Zhao,Qingying Fang,Ming'en Cheng,Huasheng Peng,Luqi Huang
Introduction Astragali Radix has been used for over 2000 years in traditional Chinese medicine. Its secondary xylem “Jinjing” and secondary phloem “Yulan” are important for evaluating the quality of the Daodi medicinal material in China. However, its systematic characterisation has not been conducted. Objective This study aims to investigate the colour, chemical compounds, and antioxidant capacity of the secondary xylem and phloem of Astragali Radix on the basis of untargeted metabolomics, broadening the application scope of Astragali Radix in food and pharmaceutical industries. Methods The L* , a* , and b* of the secondary xylem and phloem were measured by colorimetry, and the chemical compounds were identified and quantified by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and high-performance liquid chromatography-diode array detector-evaporative light scattering detection. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays were conducted to evaluate their antioxidant capacity. Results Thirty-one compounds were identified by UPLC-Q-TOF-MS. The secondary xylem exhibited high parameter b* , flavonoid content, and antioxidant capacity, while the secondary phloem was rich in astragalosides. The colour parameters of well-defined type A significantly varied from those of the other types. Well-defined type A also exhibited the highest antioxidant activity and flavonoid content, followed by middle type A-like, middle type B-like, and yellow shading type B. Conclusion The colour parameters, chemical compounds, and antioxidant capacity among the different transverse sections of secondary xylem and phloem varied. The yellow colour of secondary xylem was correlated to high flavonoid content and antioxidant activity, and well-defined type A of Astragali Radix had better quality than other types.
危险品化学品经营许可证（带存储）