Microbial transformations of flavanone by Aspergillus niger and Penicillium chermesinum cultures

As a result of biotransformation of flavanone (1) by the strain Aspergillus niger MB (being the UV mutant) and by the wild strain Penicillium chermesinum 113 the products of hydroxylation at C-6 (2) and C-4′ (5) were obtained. Additionally, three dihydrochalcones with hydroxyl groups at C-2′ (4), C-2′ and C-5′ (3) and C-2′ and C-4 (6) were formed.