Title |
Mycobiota of ground red pepper and their aflatoxigenic potential |
Author |
Hyeonheui Ham, Sosoo Kim, Min-Hee Kim, Soohyung Lee, Sung Kee Hong, Jae-Gee Ryu, and Theresa Lee* |
Address |
Microbial Safety Team, National Institute of Agricultural Sciences, Rural Development Administration, Wanju 55365, Republic of Korea |
Bibliography |
Journal of Microbiology, 54(12),832-837, 2016,
|
DOI |
10.1007/s12275-016-6480-2
|
Key Words |
ground red pepper, fungi, Aspergillus, aflatoxin |
Abstract |
To investigate contamination of ground red pepper with fungi
and mycotoxin, we obtained 30 ground red pepper samples
from 15 manufacturers in the main chili-pepper-producing
areas in Korea. Fungal contamination was evaluated by spreading
diluted samples on potato dextrose agar plates. The total
fungi counts ranged from 0 to 7.3 × 103 CFU/g. In the samples,
the genus Aspergillus had the highest incidence, while
Paecilomyces was isolated most frequently. The next most
frequent genera were Rhizopus, Penicillium, Cladosporium,
and Alternaria. Within Aspergillus, A. ruber was predominant,
followed by A. niger, A. amstelodami, A. ochraceus, A. terreus,
A. versicolor, A. flavus, and A. fumigatus. The samples were
analyzed for aflatoxins, ochratoxin A, and citrinin by ultraperfomance
liquid chromatography (UPLC) with a fluorescence
detector. Ochratoxin A was detected from three samples
at 1.03‒2.08 μg/kg, whereas no aflatoxins or citrinin were
detected. To test the potential of fungal isolates to produce
aflatoxin, we performed a PCR assay that screened for the
norB-cypA gene for 64 Aspergillus isolates. As a result, a single
800-bp band was amplified from 10 A. flavus isolates, and
one Aspergillus sp. isolate. UPLC analyses confirmed aflatoxin
production by nine A. flavus isolates and one Aspergillus
sp. isolate, which produced total aflatoxins at 146.88‒909.53
μg/kg. This indicates that continuous monitoring of ground
red pepper for toxigenic fungi is necessary to minimize mycotoxin
contamination. |