Anti-tumour and immuno-stimulating activities of the fruiting bodies of Paecilomyces japonica, a new type of Cordyceps spp.

The anti-tumor and immuno-stimulating activities of the fruiting bodies of Paecilomyces japonica (PJ), grown on silk-worm larvae and of Cordyceps sinensis (CS), a wild form of Cordyceps Fungi, were investigated. Ethanol extracts of both fungi, when administered for 9 consecutive days, at 50 and 100 mg/kg i.p., caused a significant increase in life span and a significant decrease in tumor weights and volumes, in mice inoculated with Sarcoma-180 tumor cells. Both fungal extracts were demonstrated to exhibit phagocytosis enhancing activity as measured by carbon clearance in mice. PJ extracts, when administered i.p. at 50 mg/kg/day for 3 consecutive days, exhibited a significant enhancement of phagocytosis, its potency as expressed by the regression coefficient ratio, RCtr/RCc, being 1.64 (the phagocytosis index = 2). This was approximately the same for that of zymosan (RCtr/RCc = 1.55, PI = 2), a typical phagocytosis enhancer, whereas CS extracts exhibited a moderate phagocytosis enhancing activity at the same dose level (RCtr/RCc = 1.30, PI = 1). Both fungal extracts caused a significant increase in an acid phosphatase activity, representing lysosomal enzymes, in macrophages at 20 and 100 micro g/ml in vitro, in compliance with in vivo results. These results suggest that the anti-tumor activity of both fungi might be related to an immuno-stimulating function. Copyright 2003 John Wiley & Sons, Ltd.