Incubation of Spheroplats of Anabaena variabilis (Cyanobacteria) with 22 the 2,6-O-dimetyl-ß-cycoldextrin complex of 2,3-dimethyl-5-phytylhydroquinone (11), revealed the presence of a hitherto unknown enzyme which catalyzes the cyclization of th substrate 11 to give enantiomerically pure γ-tocopherol (3) in ⩾ 93% yield.