Secondly, random amplification of polymorphic DNA (RAPD) amplifications or SmaI digestion selleck kinase inhibitor allowed us to differentiate (1) A. flavus, A. oryzae and A. minisclerotigenes; (2) A. parasiticus, A. sojae and A. arachidicola; (3) A. tamarii, A. bombycis and A. pseudotamarii. Among the 11 species, only A. parvisclerotigenus cannot be differentiated from A. flavus. Using the results of real-time PCR, RAPD and SmaI digestion, a decision-making tree was drawn up to identify nine of the 11 species of section Flavi. In contrast to
conventional morphological methods, which are often time-consuming, the molecular strategy proposed here is based mainly on real-time PCR, which is rapid and requires minimal handling. Aspergillus section Flavi includes six economically important species that are very closely related morphologically and phylogenetically, and which are often separated into two groups Ruxolitinib in vivo on the basis of their impact on food or human health. The first group includes Aspergillus flavus, Aspergillus parasiticus and Aspergillus nomius, which can cause serious damage to stored food products such as wheat and rye grain, nuts, spices and peanuts (Kurtzman et al.,
1987; Moody & Tyler, 1990a; Samson et al., 2000; Rigo et al., 2002; Hedayati et al., 2007). Furthermore, these species can produce carcinogenic secondary metabolites, the aflatoxins (Klich & Mullaney, 1987; Kurtzman et al., 1987; Yuan et al., 1995; Samson et al., 2000; Hedayati et al., 2007). After Aspergillus fumigatus, A. flavus is known as the second cause of human invasive aspergillosis (Denning, 1998; Latgé, 1999; Hedayati et al., 2007). Often, the name A. flavus is mistakenly used to describe the different species of Aspergillus section Flavi. Other recently described species are included in this group but these species are less important economically or rarely isolated. Indeed,
Aspergillus bombycis was described by Peterson et al. (2001) from nine isolates collected in silkworm-rearing houses. A variety of A. flavus, A. flavus var. parvisclerotigenus, has been raised to species level by Frisvad et al. (2005) as Aspergillus parvisclerotigenus. Aspergillus arachidicola Casein kinase 1 and Aspergillus minisclerotigenes were described by Pildain et al. (2008). Seven strains of A. arachidicola were isolated in Argentina from Arachis. Some of the 15 strains of A. minisclerotigenes were been described for a long time as A. flavus group II by Geiser et al. (1998a, b, 2000), before being raised to the species rank by Pildain et al. (2008). Hence, many authors have shown evidence that A. flavus sensu lato may consist of several species (Geiser et al., 1998a, b, 2000; Pildain et al, 2008). The second group of the section Flavi comprises the nonproducing aflatoxin species Aspergillus tamarii, Aspergillus oryzae and Aspergillus sojae. The last two have lost the ability to produce aflatoxins (Samson et al., 2000) and are widely used as a koji mold for the production of fermented foods in some Asian countries.