Figure 5. Three day-old growth of the isolate of Aspergillus flavus on yeast extract sucrose agar (supplemented with methyl β-cyclodextrin and sodium desoxycholate), incubated at 30 °C. A: Three day-old growth of a clinical isolate of Aspergillus flavus on yeast extract sucrose agar (supplemented with methyl β-cyclodextrin and sodium desoxycholate), incubated at 30 °C. A beige ring (arrow) has formed around the colony. Formation of a beige ring was noted significantly more frequently in aflatoxin-producing strains than in aflatoxin-nonproducing strains. B: Three day-old growth of an environmental isolate of Aspergillus flavus on yeast extract sucrose agar supplemented with methyl β-cyclodextrin and sodium desoxycholate), incubated at 30 °C. There is no beige ring around the colony growth.