三價鉻 (Cr3+) 已應用於降低糖尿病患血糖值及改善葡萄糖耐受能力，而有機鉻具有較佳的利用率。故本研究探討富鉻靈芝發酵製程之氧氣供給條件，以提高有機鉻的轉化率。靈芝的液態發酵其三價鉻添加量以100mg/L為佳，可得菌絲產量1.78 g/L。使用5%穀粉培養液發酵後，於第七天時可得最高菌絲量3.01 g/L及有機鉻產量40.1 mg/L，其中有機鉻主要分布於細胞外，佔92%，屬於初級代謝產物。分析5%穀粉液在五升之攪拌式與氣舉式發酵槽內之氧氣傳遞係數 (KLa) 分別在11.3-111.1 hr-1和47.8-55.8 hr-1之間，將5%穀液在攪拌式發酵槽操作條件在1 vvm通氣量及300 rpm攪拌速率下之KLa為88.2 (hr-1)，進行七天液態靈芝發酵後菌絲量最高可達19.8 g/L，是搖瓶發酵的六點五倍。在此條件下以添加100 mg/L三價鉻之5%穀液進行七天進行液態富鉻靈芝發酵，菌絲生長達10.69 g/L，有機鉻產量為64.1 mg/L。

Trivalent chromium (Cr3+) has been applied in type II diabetes patients to decrease blood glucose level and improve glucose tolerance. The objectives of this study were to modulate oxygen supply to improve
organic chromium conversion in submerged fermentation of chromium enriched Ganoderma lucidum. The results showed that addition of 100 mg/L Cr3+ in liquid medium enhanced higher biomass growth (1.78 g/L).
Fermentation of G. lucidum with 150 mL of 5% cereal medium and 100 mg/L Cr3+ in a 500 mL flask reached the highest biomass of 3.01 g/L and organic chromium of 40.1 mg/L production after 7-day cultivation. The
organic chromium of G. lucidum was a primary metabolite and 92% of organic chromium was distributed in the extracellular products. The oxygen transfer coefficients (KLa) in 5-L air-lift and stirred fermentors with 5% cereal medium were analyzed. The KLa values in an air-lift fermentor increased with higher aeration rate and the KLa values were clearly improved from 11.3 to 111.1 hr-1 with the same aeration rate when agitation rate increased in a stirred fermentor. Operation at 300 rpm with KLa = 88.3 (hr-1) proride the highest biomass (19.8 g/L) than the other agitation rate. The G. lucidum fermented in a medium containing 5% cereal and 100 mg/L Cr3+ agitation at 300 rpm and 1 vvm aeration had the highest biomass (10.69 g/L) and organic chromium production (64.1 mg/L) after 7-days cultivation.