Biochem/physiol Actions Antioxidant and mucolytic agent. Increases cellular pools of free radical scavengers. Reported to prevent apoptosis in neuronal cells but induce apoptosis in smooth muscle cells. Inhibits HIV replication. May serve as a substrate for microsomal glutathione transferase. General description This certified reference material (CRM) is produced and certified in accordance with ISO/IEC 17025 and ISO Guide 34.