靈芝菌為食藥用菇中的一種，食藥用菇最吸引人的地方在其抗癌、抗腫瘤的效果，而靈芝含有特殊三萜類（特稱為「靈芝酸」），為其他植物所沒有，靈芝中所含三萜類的主要功能為：抑制癌細胞生長、抑制組織胺釋放，防止過敏、促進肝功能、促進血小板凝集、以及降血脂，防中老年人發生心血管方面的疾病，因此具有相當潛力被開發為未來醫療用品，或作為近年來國內相當熱門的保健食品。 靈芝主要生長在腐樹或樹木的根部，屬於非褶菌目，靈芝科。由於其子實體生長緩慢，野生靈芝很少見到且質量不容易控制，導致在市面上的價格相當昂貴，難以廣泛應用於醫療用藥品。因此當今以人工培養的方式來進行學術上研究以及提供市場上需求，其中以液態培養具有相當潛力，其優點為：菌絲體生長速度較快、所需空間較小、汙染的機率較低，基於上述幾點描述，此研究將利用液態培養的方式來增加總三萜的含量。 過去增加總三萜的方法，大部分著重於培養基的改變，以及環境因子的操控，近年有學者探討兩階段式發酵，由於三萜的生產是因為靈芝菌受到環境限制而產生的二次代謝物，因此第一階段讓菌體快速生長，第二階段在菌體生長到最高峰時改變環境因子增加總三萜產量。 本計畫嘗試開發兩階段發酵製程系統，在第二階段加入酵母菌進行共培養來提升總三萜的產量，並探討共培養機制。實驗結果顯示，第二階段以靜置操作及酵母菌接菌量5%(v/v)能產出最高三萜量171.5 mg/g DW，由實驗結果可發現，酵母菌所產生的酒精為三萜產量增加之主因。 ;Ganoderma lucidum is one of the medicinal mushrooms. The most attractive characteristic of the medicinal mushrooms is its anti-tumor effect. Ganoderma lucidum has gained wide popularity as a health food and became the most valuable mushroom in Taiwan. However, because of its host specificity, slow growth rate and rarity in nature, the fruiting bodies of Ganoderma lucidum have become expensive mushrooms in recent years. Thus, investigators have exerted their efforts to prepare this mushroom from submerged culture. The main objectives of this proposal are to develop two-stage fermentation system. In first stage, we make the Ganoderma lucidum grow in high speed for 8 days, and Saccharomyces cerevisiae was added to the fermentation broth in second stage with aerated or static process to enhance ganoderic acids production. The amount of ganoderic acids reached 171.5 mg/g DW by using static operation with 5%(v/v) of inoculation level of the Saccharomyces cerevisiae in 250 ml shake flask. A novel two stage operation to optimize triterpenoids production of a co-culture was proposed and successfully demonstrated, reaching highest ganoderic acids content obtained in this study.
