Academic journal article Iranian Journal of Public Health

Candida Parapsilosis as a Potent Biocontrol Agent against Growth and Aflatoxin Production by Aspergillus Species

Academic journal article Iranian Journal of Public Health

Candida Parapsilosis as a Potent Biocontrol Agent against Growth and Aflatoxin Production by Aspergillus Species

Article excerpt

Abstract

Background: Aflatoxin contamination of food and feed stuffis a serious health problem and significant economic concerns. In the present study, the inhibitory effect of Candida parapsilosis IP1698 on mycelial growth and aflatoxin production in aflatoxigenic strains of Aspergillus species was investigated.

Methods: Mycelial growth inhibitions of nine strains of aflatoxigenic and non-aflatoxigenic Aspergillus species in the presence of C. parapsilosis investigated by pour plate technique at different pH, temperature and time of incubation. Reduction of aflatoxin was evaluated in co-cultured fungi in yeast extract sucrose broth after seven days of incubation using HPLC method. The data were analyzed by SPSS 11.5.

Results: The presence of the C. parapsilosis at different pH did not affect significantly the growth rate of Aspergillus isolates. On the other hand, temperature and time of incubation showed to be significantly effective when compared to controls without C. parapsilosis (Pā‰¤0.05). In aflatoxigenic strains, minimum percentage of reductions in total aflatoxin and B1, B2, G1, G2 fractions were 92.98, 92.54, 77.48, 54.54 and 72.22 and maximum percentage of reductions were 99.59, not detectable, 94.42, and not detectable in both G1 and G2, respectively.

Conclusion: C. parapsilosis might employ as a good biocontrol agent against growth and aflatoxin production by aflatoxigenic Aspergillus species

Keywords: Biocontrol, Candida parapsilosis, Detoxification, Aflatoxin B1, HPLC

Introduction

Aflatoxins (AFTs) are difuranocoumarin derivatives produced via polyketide pathway by many strains of Aspergillus flavus, A. parasiticus, A. bombycis, A. ochraceus, A. nomius and A. pseudotamari. Among them A. flavus is not only a medically important agent, but also a common contaminant of many important agricultural products (1, 2). AFTs are potential threats to human and animal health through consumption of AFTs contaminated food and feed stuff. They are considered as potent hepatotoxic and hepatocarcinogenic agent and can adversely affect on cell mediated immune response, causing reduction of phagocytosis and depression of complement and interferon production (3).

The International Agency for Research on Cancer (IARC), classifies naturally occurring aflatoxins and aflatoxin B1 (AFB1) as group 1 carcinogens for human (4). The aflatoxins are food-borne mycotoxins likely to be of greatest impact in Africa and other tropical developing countries. Aflatoxins attract worldwide attention because of the significant economic losses related to their effect on human and animal health (5, 6). Several studies were carried out to diminish the contamination of human and animal foods through chemical, physical, and biological methods that convert the toxins into less harmful materials with less mutagenic effects (7). It is well - known that many microbial agents have antifungal activity against Aspergillus section flavi (8, 9). It is reported that a number of Bacillus, Pseudomonas, Ralstonia and Burkholderia strains could completely inhibit the growth of A. flavus (10). Some species of saprophytic yeast such as Candida krusei, Pichia anomala (11), P. guilliermondii (12), Kluyveromyce spp. (13) and moulds such as A. oryzae, A. niger, and Rhizopus oryzae (14,15) have been shown inhibitory effects on the growth of Aspergillus flavus and/ or its aflatoxin production in vitro (11,16). Strains of lactic acid bacteria, Rhodococcus erythropolis and Mycobacterium fluorantheniorans sp. Nov DSM44556T and some strains of Saccharomyces cerevisiae showed to have probiotic activity (17-19).

The objective of this study was to evaluate the inhibitory effect of C. parapsilosis on mycelial growth and AFTs production of aflatoxigenic Aspergillus strains.

Materials and Methods

Chemicals and instrumental analyses

The mixture standard solutions of AFB1, AFB2, AFG1, AFG2, purchased from Sigma (St. Louis, MO, USA). ā€¦

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.