“… L-cysteine was attenuated or completely abolished by co-… mM), a potent free radical scavenger, piperonyl butoxide (1 mM), an inhibitor of mixed function oxidase, or cobalt chloride (0.01, 0.02 or … inhibitor of mixed function oxidase, but not allopurinol (0.1 mM), an inhibitor of xanthine oxidase.”