利用蛹蟲草發酵黃耆來開發抗腫瘤活性製品

Abstract

黃耆是常見的中藥，具有促進淋巴細胞增生、免疫調節、抗癌活性和抗肝損傷等功能。本研究即利用黃耆當作培養基以蛹蟲草當作菌種進行發酵，期望得到具有抗癌活性之發酵產品。結果顯示相較於化學合成培養基，以黃耆當作培養基之發酵濾液擁有較高之抗癌活性，其抑制癌細胞生長能力（IC50）對人類胃癌細胞AGS、人類乳癌細胞MCF-7、人類肝癌細胞Hep G2和老鼠大腸癌細胞CT26分別為465、37、25 和20 μg/mL。進一步以CT26接種於BALB/c小鼠之動物模式來評估抗癌活性，實驗結果指出相較於控制組，當每天以管餵方式餵食100 mg/kg BW/day和200 mg/kg BW/day劑量時，可以有效抑制腫瘤的體積達43.81 %和48.89 %，而腫瘤重量的抑制率方面分別為31.21 %和39.48 %，皆能有效的抑制腫瘤生成。此外，發酵濾液在動物實驗過程中並無發現對於小鼠臟器有任何明顯的副作用。在成分分析方面，結果顯示，黃耆皂苷、黃耆異黃酮皆非主要抗癌活性來源，接著以HPLC進行分離純化後，發現波鋒2與蟲草素組合時具有最好的抗癌活性表現。

Radix astragalus is widely used in China. Radix astragalus was demonstrated to have various bioactivities such as lymphocyte proliferation, immune-regulation, anti-tumor activity, and anti-liver injury. This study used Radix astragali (RA) as the medium for culturing Cordyceps militaris to investigate the anti-tumor activity of the fermentation broth. It was found that the product from culturing C. militaris in RA medium had a better anti-tumor activity than that culturing in synthetic medium. The fermentation broth inhibited the growth of four tumor cells including human gastric cancer AGS cells, human breast cancer MCF-7 cells, human hepatocellular carcinoma Hep G2 cells and murine colorectal adenocarcinoma CT26 cells with IC50 465μg/mL, 37μg/mL, 25μg/mL, and 20μg/mL, respectively. To validate the anti-tumor activity, the BALC/c mice were implanted with CT26 cells and then fed with various dosages of the fermentation product. It was found that 20 mg/kg body weight (BW)/day group had no significant anti-tumor activity as compared to the control group. The dosage of 100 mg/kg BW/day and 200 mg/kg BW/day group inhibited the tumor volume by 43.81% and 48.89%. Tumor weight was also reduced by 31.21% and 39.48% compared to the control group. Besides, the fermentation broth didn’t impose serious side effect on the vital organs of the mice as compared to the chemotherapeutic drug 5-FU. After constituent analyses, the results showed that saponins and isoflavonoids of Astragalus were not the major anti-tumor components. Through HPLC isolation, when cordycepin combined with peak 2 had the strongest anti-tumor activity.