The CC double bond of non-substituted and substituted maleimides were hydrogenated to the corresponding succinimides by fungal strains. 2-and 2, 3-methylated-phenyl-maleimides were enantioselectively reduced to (R)-N-phenyl-3-methylsuccinimide and to trans-(R, R)-N- phenyl-2, 3-dimethylsuccinimide respectively by Aspergillus niger, A. flavus and A. fumigatus (conversion 96 to 99%), Fusarium graminearum and Penicillium sp (conversion: ...