Potent Antifungal Activity of Pure Compounds from Traditional Chinese Medicine Extracts against Six OralCandidaSpecies and the Synergy with Fluconazole against Azole-ResistantCandida albicans

Zhimin Yan,Hong Hua,Yanying Xu,Lakshman P Samaranayake

doi:10.1155/2012/106583

Abstract

This study was designed to evaluate the in vitro antifungal activities of four traditional Chinese medicine (TCM) extracts. The inhibitory effects of pseudolaric acid B, gentiopicrin, rhein, and alion were assessed using standard disk diffusion and broth microdilution assays. They were tested against six oral Candida species, Candida albicans, Candida glabrata, Candida tropicalis, Candida krusei, Candida dubliniensis, and Candida guilliermondii, including clinical isolates from HIV-negative, HIV-positive, and Sjögren's syndrome patients. It was found that pseudolaric acid B had the most potent antifungal effect and showed similar antifungal activity to all six Candida spp, and to isolates from HIV-negative, HIV-positive, and Sjögren's syndrome patients. The MIC values ranged from 16 to 128 μg/mL. More interestingly, a synergistic effect of pseudolaric acid B in combination with fluconazole was observed. We suggest that pseudolaric acid B might be a potential therapeutic fungicidal agent in treating oral candidiasis.

Highlights

Candida species are commensal fungi that are found in 30– 50% of human oral cavities
An important trend that can be detected with the incidence of oral candidiasis is an increase in the number of infections related to the non-albicans Candida species such as Candida glabrata, Candida krusei, and Candida tropicalis
This situation poses a clinical challenge because some non-albicans Candida species are inherently resistant to first-line antifungals such as fluconazole, especially in medically complex groups of patients [4, 5]

Summary

Introduction

Candida species are commensal fungi that are found in 30– 50% of human oral cavities. An important trend that can be detected with the incidence of oral candidiasis is an increase in the number of infections related to the non-albicans Candida species such as Candida glabrata, Candida krusei, and Candida tropicalis. This situation poses a clinical challenge because some non-albicans Candida species are inherently resistant to first-line antifungals such as fluconazole, especially in medically complex groups of patients [4, 5]. Novel fungal therapies for effective management of Candida infections are urgently required

Objectives

Methods

Conclusion