Aspergillus and Ochratoxin A in Latin America

Abstract

Species within Aspergillus section Nigri and section Circundati are important sources of ochratoxin A (OTA) contamination in several foods and beverages such as cereals, grapes, spices, peanut, cocoa, wine, beer, and coffee worldwide. Few surveys showed the epidemiology, ecology, and distribution of black aspergilli occurring in crops from different Latin American regions. Within section Nigri, Aspergillus niger aggregate species are commonly the most prevalent, followed by A. carbonarius and Aspergillus uniseriate. Aspergillus ochraceus is the most important ochratoxigenic species included in the section Circundati. These species differ in their OTA-producing ability, since the percentage OTA-producer strains and the levels produced are variable. The OTA levels detected in grains and fruits also were variable, and it was shown that their damage affected the incidence of ochratoxigenic species and OTA contamination. Temperature and water activity were also key factors determining the Aspergillus section Nigri colonization and OTA accumulation in different commodities. The knowledge of the factors affecting preharvest and post-harvest contamination of foods by black aspergilla and OTA production is essential to improve the quality and safety of foods. Different strategies can be used to reduce the impact of Aspergillus and OTA accumulation. Alternative strategies to the chemical control can be biocontrol or the use of natural substances such as antioxidants and essential oils. The data presented in this review provide relevant information for using appropriate management strategies to reduce or prevent the development of ochratoxigenic species and OTA accumulation on different commodities relevant for Latin America.

Logistic regression applied to the incidence of Aspergillus producer of mycotoxin in cocoa beans cultivated in the state of Rondnia, Brazil

“…In relation to the geographical position of the cultivation areas, several studies with grapes had already demonstrated that the geographic area and meteorological con-ditions may contribute to the incidence of fungi and production of OTA (Battilani et al, 2006a, b;Bellí et al, 2006;Chiotta et al, 2009;Serra et al, 2006), however no study was done with cocoa regarding this aspect until the present one. In this context, when considering latitude, longitude and temperature, a higher probability of occurrence of total fungi of the genus Aspergillus was estimated for municipalities of the state of Rondônia, Brazil, located between the parallels of 11° and 13° of South latitude and meridians of 60° and 62° of West longitude, which correspond to Vilhena, Colorado do Oeste, Cacoal, São Felipe d'Oeste and Urupá.…”

“…A positive correlation of A. carbonarius on grapes with temperature was already related, and the higher occurrence of this species occurred on hot areas (Battilani et al, 2006a;Chiotta et al, 2009). A. carbonarius grows on temperatures between 10 and 40°C (Pitt, 2000), with optimum between 25-35°C (Bellí et al, 2004b;Mitchell et al, 2004).…”