A novel oxime polyketide, maydisone (1), along with two known compounds, 7-hydroxy-2,5-dimethylchromone (2) and 2,5-dimethylbenzoic acid (3) were isolated from the cultures of Bipolaris maydis. Their structures were identified by the application of NMR and MS data analyses and comparison with previous reports. Compound 1 showed the most powerful inhibition of α-glucosidase, with an IC50 value of 68.30 ± 0.83 µM.
Keywords: Bipolaris maydis; maydisone; oxime polyketide; α-glucosidase inhibition.