Optimal conditions for cordycepin production in surface liquid-cultured Cordyceps militaris treated with porcine liver extracts for suppression of oral cancer

Liang-Tzung Lin ^a,b,1, Ying-Jang Lai ^c,1, She-Ching Wu ^d, Wei-Hsuan Hsu ^e,*, Chen-Jei Tai ^f,g,h,*

^a Department of Microbiology and Immunology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan

^b Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, Taiwan

^c Department of Food Science, National Quemoy University, Jinning, Kinmen, Fujan, Taiwan

^d Department of Food Science, National Chiayi University, Chiayi City, Taiwan

^e Biochemical Process Technology Department, Center of Excellence for Drug Development, Biomedical Technology and Device Research Laboratories, Industrial Technology Research Institute, Chutung, Hsinchu, Taiwan

^f Department of Traditional Chinese Medicine, Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan

^g Department of Obstetrics and Gynecology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan

^h Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei, Taiwan

Cordycepin is one of the most crucial bioactive compounds produced by Cordyceps militaris and has exhibited antitumor activity in various cancers. However, industrial production of large amounts of cordycepin is difficult. The porcine liver is abundant in proteins, vitamins, and adenosine, and these ingredients may increase cordycepin production and bioconversion during C. militaris fermentation. We observed that porcine liver extracts increased cordycepin production. In addition, air supply (2 h/d) significantly increased the cordycepin level in surface liquid-cultured C. militaris after 14 days. Moreover, blue light light-emitting diode irradiation (16 h/d) increased cordycepin production. These findings indicated that these conditions are suitable for increasing cordycepin production. We used these conditions to obtain water extract from the mycelia of surface liquid-cultured C. militaris (WECM) and evaluated the anti-oral cancer activity of this extract in vitro and in vivo. The results revealed that WECM inhibited the cell viability of SCC-4 oral cancer cells and arrested the cell cycle in the G2/M phase. Oxidative stress and mitochondrial dysfunction (mitochondrial fission) were observed in SCC-4 cells treated with WECM for 12 hours. Furthermore, WECM reduced tumor formation in 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis through the downregulation of proliferating cell nuclear antigen, vascular endothelial growth factor, and c-fos expression. The results indicated that porcine liver extracts irradiated with blue light light-emitting diode and supplied with air can be used as a suitable medium for the growth of mycelia and production of cordycepin, which can be used in the treatment of oral cancer.