Investigating the Inhibitory Effect of Turmeric Extract in Reducing Aflatoxin Production by Aspergillus flavus and Aspergillus parasiticus

The consumption of pistachios (<em>Pistacia vera</em> L.) has been increasing due to their significant contribution to human health. Apart from being a valuable nutritional resource, they have been linked to potential chemical risks, including mycotoxins, which can lead to fungal contamination and secondary metabolism. In this study, after optimizing the extraction of turmeric extract based on the amount of total phenol and flavonoid compounds, treatments were applied using different concentrations of turmeric extract to assess its impact on the growth of <em>Aspergillus flavus</em> and <em>Aspergillus parasiticus</em>, and aflatoxin production. The treatments included various concentrations of turmeric extract and were implemented in a completely randomized design with three replications for each treatment. Results showed that the ultrasonic extraction method at 50 &ordm;C for 60 minutes yielded the highest efficiency of turmeric extract. Specifically, the application of 300 &mu;L turmeric extract significantly inhibited the mycelial growth of <em>Aspergillus flavus</em>, while 350 &mu;L extract was more effective in inhibiting the growth of <em>Aspergillus parasiticus</em>. Furthermore, incubating both fungi with turmeric extract at 25&deg;C for 3 days demonstrated a notable inhibitory effect on aflatoxin production. Additionally, the addition of turmeric extract to pistachios contaminated with both fungi effectively prevented aflatoxin production. Therefore, turmeric extract, particularly at concentrations of 300 &mu;L and 350 &mu;L, shows potential as a natural compound for preventing aflatoxin production in pistachios.