Killing effect of the combined treatment of ultrasound and hypocrellin B on Candidaalbicans

OBJECTIVE To investigate the killing effect of the combined treatment of ultrasound and hypocrellin B,an active component isolated from a natural product Hypocrella bambuase,on Candida albicans.METHODS At first,Candida albicans are incubated with hypcrellin B and the uptake of hypocrellin B in Candida albicans was determined using fluorescence intensity analysis.And then the sensitized Candida albicans were exposed to low-intensity of ultrasound.After the combined treatment of ultrasound and hypocellin B,the growth of Candida albicans was evaluated using the colony counting method,and membrane integrity of Candida albicans was also analyzed by a flow cytometry with propidium iodide staining.RESULTS Hypocrellin B was fast absorbed by candida albicans.The growth of candida albicans was more significantly inhibited by the combined treatment of ultrasound and hypocrellin B than the controls(P<0.05).The more marked damages to membrane integrity were found in the combined treatment than the controls(P<0.05).CONCLUSION The combined treatment of ultrasound and hypocrellin B had significant killing effect on Candida albicans,indicating sonodynamic therapy with hypocrellin B from natural product might be a potential approach for combating fungal infections.

Effect of sonodynamic action of hypocrellin B on biofilm-producing Enterococcus faecalis

OBJECTIVE To investigate the effect of sonodynamic action on biofilm-producing Enterococcus faecalis using hypocrellin B from a natural product Hypocrella bambuase as a sensitizer.METHODS The uptake of hypocrellin B in biofilm-producing Enterococcus faecalis was measured using the fluorescent analysis method.After the combined treatment of hypocrellin B and ultrasound,the growth of biofilm-producing Enterococcus faecalis was measured using the colony counting method,the membrane integrity was detected using a flow cytometric analysis with propidium iodide staining.Chromosomal DNA of bacteria was analysed using apulsed-field gel electrophoresis(PFGE).RESULTS The uptake of hypocrellin B in biofilm-producing Enterocuccus faecalis reached a high peak at the 20 min incubation.After the combined treatment of hypocrellin B,the growth of biofilm-producing Enterocuccus faecalis significantly descreased and membrane integrity was remarkably damaged.However,no remarkable change in bacterial DNA was found.CONCLUSION Sonodynamic action of hypocrellin B had significant killing activity on Enterocuccus faecalis.