Vol. 9(21), pp. 1394-1401, 27 May, 2015
DOI: 10.5897/AJMR2015.7408
Article Number: 099ACD753272
ISSN 1996-0808
Copyright © 2015
Author(s) retain the copyright of this article
http://www.academicjournals.org/AJMR
African Journal of Microbiology Research
Full Length Research Paper
Logistic regression applied to the incidence of
Aspergillus producer of mycotoxin in cocoa beans
cultivated in the state of Rondônia, Brazil
Danieli Cristina Schabo
1
*, Luísa Freire
2
, Camila Alvarenga Freire
2
, Fabiana Reinis Franca
Passamani
2
, Marcelo Angelo Cirillo
3
and Luís Roberto Batista
2
1
Department of Education, Federal Institute of Education, Science and Technology of Rondônia, Colorado do Oeste,
RO, Brazil.
2
Department of Food Science, Federal University of Lavras, Lavras, MG, Brazil.
3
Department of Exact Sciences, Federal University of Lavras, Lavras, MG, Brazil.
Received 3 February, 2015; Accepted 7 May, 2015
The presence of fungi of the genus Aspergillus must be investigated because it is related to the
diminishment of quality and consequently to the risk to health of consumers due to the possible
production of mycotoxins. In this context, this study was performed with the aim to evaluate the
presence of Aspergillus species in cocoa beans produced in the state of Rondônia, Brazil, as well as
verify the toxigenic potential of these species and the effect of the geographical origin on the incidence
of toxigenic and non-toxigenic species of fungi. The technique of logistic regression was used to
estimate the probability of occurrence of the genus Aspergillus. A total of 185 Aspergillus were
identified. Among the tested Aspergillus carbonarius, 79.41% produced ochratoxin on levels from 0.08
to 44.09 μg/g in the culture medium. For the other Aspergillus species, the production potential was only
assessed, and 3.13% of the A. niger presented potential to produce OTA and 83.33% of A. flavus which
was able to produce aflatoxins. The presence of these toxigenic species indicates a potential risk of
mycotoxin in cocoa beans and in their derived products in the studied region. Besides, the occurrence
of Aspergillus species differed in function of geographical coordinates and temperature, presenting
higher probability of occurrence on cocoa beans of municipalities located in Southern Rondônia, Brazil.
Key words: Cocoa beans, Aspergillus, mycotoxins, ochratoxin A, aflatoxins, logistic regression, thin layer
chromatography, high performance liquid chromatography.
INTRODUCTION
The importance of cocoa to the industry is attributed to its
beans, from which the chocolate and other by products
are obtained. Brazil is the sixth largest cocoa producer of
the world (International Cocoa Organization, 2013),
*Corresponding author. E-mail: danieli.schabo@ifro.edu.br. Tel/Fax: +55 69 3341-2644.
Author(s) agree that this article remains permanently open access under the terms of the Creative Commons Attribution License 4.0
International License