Journal of Functional Foods
·
2020
·
IF 3.701
Gang Li,Jing Zhou,Mengyu Sun,Juren Cen,Jing Xu
Luteolin derived from Clerodendrum cyrtophyllum Turcz leaves exhibited antioxidant activity. The IC 50 values of luteolin for ABTS· + and DPPH· free radical scavenging was 17.3 ± 0.82 μM and 13.2 ± 0.18 μM, respectively, and the compound showed better antioxidant activities than BHT (Butylated hydroxytoluene) and VC (Vitamin C). Luteolin exhibited neither cytotoxic nor promotional activities and no genotoxic effect toward HepG2 cells. The cell viability was significantly increased in a dose-dependent manner after preincubation of the cells with 1–40 μM luteolin followed by direct exposure to TBHP ( tert -Butyl hydroperoxide). At the concentration of 30 μM, luteolin can reduce intercellular reactive oxygen species accumulation by 43.7 ± 3.98%, lactate dehydrogenase release by 38.7 ± 3.07% malondialdehyde levels by 24.5 ± 1.14% and increased 73.7 ± 6.04% superoxide dismutase activity and 72.3 ± 1.75% glutathione activity. A western blot assay showed that luteolin upregulated procaspase-3 and downregulated cleaved caspase-3 to counteract TBHP-triggered oxidative stress. Our study lays a theoretical foundation for the utilization and further development of luteolin as a promising natural antioxidant.
研究领域:
药理学
·
细胞生物学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Microbiology
·
2026
·
IF 5.8
Yue Hu,Wenwen Luo,Chengjian Tan,Guoshun Pei
IntroductionClerodendrum cyrtophyllum Turcz., a traditional Chinese medicinal plant, exhibits broad bioactivity. Nevertheless, the flavonoid constituents conferring anti-Staphylococcus aureus (S. aureus) activity and their mechanistic basis remain to be elucidated.MethodsTotal flavonoid extraction from Clerodendrum cyrtophyllum Turcz. (TFC) was first evaluated by single-factor experiments to screen key variables and subsequently optimized by a Box–Behnken design (BBD) within response surface methodology (RSM). followed by purification with D101 macroporous resin. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) characterized the chemical profile. Antibacterial activity against S. aureus was assessed via inhibition zones, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and growth curves. Mechanisms were explored by evaluating cell surface hydrophobicity (CSH), extracellular alkaline phosphatase (AKP), leakage of nucleic acids/proteins, membrane potential, ATP levels, reactive oxygen species (ROS) content, and morphological alterations.ResultsThe optimal extraction conditions for TFC were determined as 70% ethanol as the solvent, an extraction time of 102 min, a temperature of 64 °C, and a solid–liquid ratio of 1:25 (g: mL), resulting in a yield of 6.48% ± 0.58. After purification, the purity of TFC was increased to 76%, and preliminary analysis identified 85 flavonoid constituents. TFC exhibited inhibition zone diameters of 13 ± 0.45 mm, 16 ± 0.38 mm, and 20 ± 0.45 mm at concentrations of 50, 100, and 150 mg/mL, respectively, with MIC and MBC values of 0.781 mg/mL and 1.562 mg/mL. Notably, TFC effectively inhibited the growth of S. aureus within 24 h. Mechanistic investigations revealed that TFC treatment increased S. aureus CSH and decreased the membrane potential, leading to the leakage of intracellular nucleic acids and proteins, indicating damage to S. aureus cells, which was further confirmed by SEM. Furthermore, TFC induced significant intracellular ATP depletion, decreased intracellular nucleic acids and protein contents, and triggered excessive ROS production.ConclusionThis study optimized the extraction conditions of TFC and successfully obtained TFC rich in multiple flavonoid constituents. TFC exerts potent inhibitory effects on S. aureus by disrupting the integrity of cell walls and membranes, depleting intracellular energy reserves, decreasing the contents of intracellular nucleic acids and proteins, and inducing intracellular oxidative stress.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）