Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/32331
Title: Hypericin-mediated photodynamic antimicrobial effect on clinically isolated pathogens
Authors: Yow, CMN
Tang, HM
Chu, ESM
Huang, Z
Issue Date: 2012
Publisher: Wiley-Blackwell
Source: Photochemistry and photobiology, 2012, v. 88, no. 3, p. 626-632 How to cite?
Journal: Photochemistry and photobiology 
Abstract: The aim of this study was to determine the photodynamic antimicrobial effect of hypericin on clinically isolated Staphylococcus aureus and Escherichia coli cells. Bacterial cells (10 8 cells per mL) were incubated with hypericin (0-40 μm) for 30 min and followed by light irradiation of 600-800 nm at 5-30 J cm -2. Cell survival was determined by colony counting, cellular hypericin uptake examined by flow cytometer, and cell membrane damage examined by scanning electron microscopy and leakage assay. The effectiveness of hypericin-mediated photodynamic killing was strongly affected by cellular structure and photosensitizer uptake. The combination of hypericin and light irradiation could induce significant killing of Gram positive methicillin-sensitive and -resistant S. aureus cells (>6 log reduction), but was not effective on Gram negative E. coli cells (<0.2 log reduction). The difference was caused by different cell wall/membrane structures that directly affected cellular uptake of hypericin. Increasing prevalence of antibiotic-resistant bacteria is one of the most pressing global health issues. It is imperative to develop nonantibiotic approaches for combating antibiotic-resistant bacterial infections. Photodynamic antimicrobial chemotherapy (PACT) is a promising alternative. This study examined the effect of hypericin-mediated PACT on clinically isolated S. aureus and E. coli. Hypericin-mediated PACT could induce significant killing of Gram positive methicillin-sensitive and methicillin-resistant S. aureus cells (illustrated), but was ineffective on Gram negative E. coli cells. This phenomenon is due to the differences in bacterial wall/membrane structures that directly affect cellular uptake of hypericin.
URI: http://hdl.handle.net/10397/32331
ISSN: 0031-8655
EISSN: 1751-1097
DOI: 10.1111/j.1751-1097.2012.01085.x
Appears in Collections:Journal/Magazine Article

Access
View full-text via PolyU eLinks SFX Query
Show full item record

SCOPUSTM   
Citations

29
Last Week
1
Last month
0
Citations as of Aug 20, 2017

WEB OF SCIENCETM
Citations

22
Last Week
0
Last month
0
Citations as of Aug 20, 2017

Page view(s)

41
Last Week
4
Last month
Checked on Aug 20, 2017

Google ScholarTM

Check

Altmetric



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.