Background: Taxol is a diterpenoid compound that was first isolated from yew tree (Taxus brevifolia) and later from other plants such as Corylus avellana. Studies have shown that some of the endophytic fungi isolated from these plants are also capable of producing taxol. DBAT gene is one of the key genes in taxol biosynthesis pathway that catalyzes the synthesis of Baccatin III, one of the main precursors in taxol biosynthesis. The aim of this study was to investigate taxol production by endophytic fungi isolated from Corylus avellana.

Materials and Methods: In this case-control study, endophytic fungi were isolated from hazelnut trees in the Fandoghlo area, Ardabil province, and purified through hyphal tip method. Genomic DNA was extracted using CTAB method. The presence of DBAT gene was examined by polymerase chain reaction (PCR). Taxol production in fungal media was investigated via TLC (Thin Layer Chromatography) method.

Results: After purification, 60 fungi were isolated from different organs of hazelnut trees and the presence of DBAT genes in 12 isolates was proved by PCR with specific primers. Investigation of taxol production in culture of these isolates showed that 7 isolates were capable of producing taxol in laboratory conditions.

Conclusion: A group of endophytic fungi isolated from hazelnut, grown in the North West of Iran, had DBAT gene, encoding a key enzyme in the taxol biosynthesis pathway, and some were able to produce taxol in vitro.