Flavonoids extract from Portulaca oleracea L. induce Staphylococcus aureus death by apoptosis-like pathway

Figures & data

Table 1. Antibacterial activity of POFE from P. oleracea.

Bacterial strains	Source	MIC (mg/mL)	MBC (mg/mL)
S. aureus	ATCC25923	10.0 ± 0.12	10.0 ± 0.12
M. luteus	ATCC 10240	15.0 ± 0.08	20.0 ± 0.08
E. coli	ATCC25922	15.0 ± 0.06	20.0 ± 0.06
K. pneumoniae	ATCC 10031	20.0 ± 0.02	20.0 ± 0.02
S. enterica	ATCC 14028	25.0 ± 0.01	–
E. cloacae	ATCC 13047	25.0 ± 0.06	–

(–): >20 mg/mL was not detected. Data are expressed as mean values of three independent experiments.

Figure 1. POFE-induce S. aureus intracellular ROS accumulation. S. aureus cells untreated with POFCE were as the control.

Figure 2. POFE-induce S. aureus cells apoptosis-like response. (A) and (B) Results of Annexin V/PI staining. Cells were sorted into living, necrotic, early apoptotic, and late apoptotic cells. (C) and (D). Hoechst 33342/PI double staining, Cells were sorted into living, apoptotic and dead cells. (E) Results of TUNEL assays. TUNEL positive cells (green channel). Hoechst 33342 (blue channel) is used to locate the nuclei of the cells. (F) Flow cytometric analysis of caspase-like response using FITC-VAS-FMK. S. aureus cells untreated with POFE were as the control.

Figure 3. Membrane depolarisation analysis in POFE-treated S. aureus cells. (A) and (B) Mitochondrial Membrane Potential/Annexin V Apoptosis Kit analysed apoptosis based on PS translocation and changes in mitochondrial membrane potential. (C) Membrane potential (??m) was determined by using Rhodamine 123 staining and analysed by using flow cytometry. S. aureus cells untreated with POFE were as the control.