Catalyzes the conversion of 1-deoxypentalenic acid to 11-beta-hydroxy-1-deoxypentalenic acid in the biosynthesis of neopentalenolactone antibiotic. 1-deoxypentalenate + 2-oxoglutarate + O2 = 1-deoxy-11beta-hydroxypentalenate + CO2 + succinate kcat is 4.2 sec(-1) with 1-deoxypentalenic acid. Optimum pH is 6.0. Antibiotic biosynthesis; neopentalenolactone biosynthesis. S.avermitilis does not produce pentalenolactone itself in vivo but instead a group of new metabolites that are neopentalenolactone derivatives. Belongs to the PhyH family.