The activity of each purified fraction was determined by a significant increase (p < 0:05) in the production of nitric oxide (NO) production by LPS-stimulated RAW 264.7 macrophages. All purification steps were performed out at 4 C. Fresh fruiting bodies of A. polytricha (1 kg) were homogenized with 3 l of cold 5% (v/v) acetic acid with 0.1% (v/v) 2-mercaptoethanol.