RT Journal Article T1 Toxigenic Aspergillus Diversity and Mycotoxins in Organic Spanish Grape Berries A1 Melguizo Ávila, Clara Del Carmen A1 Tarazona, Andrea A1 Gil Serna, Jessica A1 Mateo, Fernando A1 Patiño Álvarez, Aurora Belén A1 Mateo, Eva María AB Grapes are frequently contaminated by Aspergillus section Nigri fungi and ochratoxin A (OTA), with A. niger also capable of producing substantial fumonisin B2 (FB2) levels. Emerging evidence suggests that aflatoxigenic fungi may eventually replace ochratoxigenic fungi in certain regions due to better adaptation to changes in climatic conditions. However, research on the toxigenic fungal community and mycotoxins in grapes from organic vineyards remains limited. Research on Spanish conventional grapes is also deficient, with most of the available literature being outdated. The present study investigates the diversity of toxigenic fungi and the presence of mycotoxins in organically cultivated grape berries in Spain, which are renowned for their significant oenological tradition. This study employed species-specific PCR protocols for fungal characterization and optimized methods for the analysis of OTA, FB2, and aflatoxin B1 (AFB1) by UPLC–ESI–MS/MS. The most prevalent species present were Aspergillus flavus, A. niger, A. parasiticus, A. steynii, A. carbonarius, and A. westerdijkiae (67.1%, 43.5%, 20.0%, 14.1%, 14.1%, and 11.8% of the samples, respectively). OTA was detected only in 16 samples (19%), averaging 0.48 ng/g and peaking at 0.7 ng/g, which were lower than previously reported for conventional grapes. There was no FB2 or AFB1 detected. This study is pioneering in its exploration of the occurrence of toxigenic mycobiota, beyond Nigri fungi, and subsequent potential for other serious mycotoxins to contaminate Spain’s organic grapes. PB MDPI SN 2072-6651 YR 2025 FD 2025-09-30 LK https://hdl.handle.net/20.500.14352/130280 UL https://hdl.handle.net/20.500.14352/130280 LA eng NO Melguizo, C., Tarazona, A., Gil-Serna, J., Mateo, F., Patiño, B., & Mateo, E. M. (2025). Toxigenic Aspergillus Diversity and Mycotoxins in Organic Spanish Grape Berries. Toxins , 17(10). https://doi.org/10.3390/TOXINS17100487 NO The authors acknowledge financial support from the Ministry of Science, Innovation and Universities (Spanish Government) through the projects with references PID2023-149211OB-C33 and PID2022-136803OB-I00. NO Ministerio de Ciencia, Innovación y Universidades (España) DS Docta Complutense RD 25 feb 2026