Fungal endophytes from Acer ginnala Maxim: isolation, identification and their yield of gallic acid

The aim of the study was to isolate the endophytic fungi from Acer ginnala and screen isolates rich in gallic acid. After epiphytic sterilization, 145 fungal endophytes were isolated from the stem, annual twig and seed of Acer ginnala. The endophytes were grouped into ten different taxa, Phomopsis sp., Neurospora sp., Phoma sp., Epicoccum sp., Penicillium sp., Alternaria sp., Fusarium sp., Trichoderma sp., Cladosporium sp. and a species of Pleosporales Incertae Sedis, by their morphological traits and ITS-rDNA sequence analysis. The content and yield of gallic acid of 141 isolates were determined by HPLC. On average, the species of Pleosporales Incertae Sedis had the highest content and yield of gallic acid (13·28 mg g⁻¹ DW; 119·62 mg l⁻¹), while Alternaria sp. had the lowest. Of 141 fungal endophytes from A. ginnala, Phomopsis sp. isolate SX10 showed both the highest content and the highest yield of gallic acid (29·25 mg g⁻¹ DW; 200·47 mg l⁻¹). Endophytic fungi isolated from A. ginnala may be used as potential producers of gallic acid and other compounds with biological activities, or functioned as elicitors to produce natural compounds.