Ganoderma lucidum and Cordyceps sinensis are medicinal fungi commonly used in Chinese medicine. The allied species of G. lucidum, G. sinense and G. tsugae as well as the allied species of C. sinensis, C. militaris are also commercially available as health supplements. The present study aimed at evaluating and comparing the biological activities of the different parts of fruiting bodies of Ganoderma species (whole fruiting body, pileus, stipe, spores and spore oil) and Cordyceps species (whole fruiting body, stroma and larva/pupa). / The extracts of C. sinensis and C. mililaris could stimulate secretion in human airway epithelial cell Calu-3, implying the potentials of these extracts to modulate the mucociliary clearance. The potencies of the stimulatory effects of the stroma of fruiting bodies showed stronger effects than the larva/pupa. All parts of C. sinensis and the stroma of C. mililaris could modulate the proliferation of human peripheral blood mononuclear cells and the different potencies of immunomodulatory effects were also observed. / The results demonstrated that the hot water extracts of G. lucidum, G. sinense and G. tsugae possessed antiproliferative effects on human breast cancer cell lines MCF-7 and MDA-MB-231. The extracts from the stipes showed stronger inhibitory activities on cancer cell proliferation than those from pilei. Furthermore, the extracts from the whole fruiting body and stipe of G. lucidum possessed strong antitumor effects on the nude mice bearing MCF-7 xenografts and the BALB/c mice bearing sarcoma S-180 allografts as well as strong immunomodulatory effects in terms of stimulating splenic lymphocyte proliferative responses. The oral administrations of spores and spore oil did not show significant inhibition on MCF-7 xenografts growth but they inhibited sarcoma allografts growth effectively. / The strong biological effects of the stipe of Ganoderma and the stroma of Cordyceps were showed for the first-time. This study sheds light on how the fruiting bodies of Ganoderma or Cordyceps should be used to achieve the most out of their pharmacological properties. This study also demonstrated the novel application of Cordyceps in promoting secretion in human airway submucosal glands, which reinforces the rationale of using this fungus for treating respiratory diseases. / Yue Gar Lee Grace. / "August 2006." / Advisers: Leung Ping Chung; Kwok Pui Fung; Bik San Clara Lau. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1584. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 318-340). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.