大量飼養禽畜會產生龐大的廢棄物並造成環境污染，尤其家禽屠宰後，產生大量不易被分解的雞毛，更成為處理上的問題。雞毛因富含角蛋白 ( keratin ) 使結構穩定，一般微生物與物理化學作用，只能有限的分解，故雞毛多當成廢棄物丟棄而無法利用。 由曝氣雞糞堆肥中發現摻雜其中的雞毛被分解，故以之作為菌種來源，並以選擇性培養基來篩選出可能具有角蛋白分解能力的26株菌，再選取具有最大雞毛分解能力的菌株進行實驗。經食品工業研究所菌種中心鑑定此菌株為Bacillus licheniformis THSC-1，其特徵為棒狀的革蘭氏陽性菌、產胞子且有產生觸? (catalase) 的能力、可在有氧與厭氧下生長等特性。並由不同範圍的溫度與pH值的條件培養此菌，發現其在50℃與培養基調整到pH 8.5時，具有最大雞毛分解能力。THSC-1為兼性菌，故以含1 ％ 、 2.5 ％ 與5 ％ 雞毛濃度的液體培養基，在有氧和厭氧條件下培養，試圖找出最佳分解雞毛的培養條件，結果THSC-1菌株在有氧條件下，總胺基酸濃度在30天發酵期中均呈現上升的趨勢，並比厭氧條件下分解能力較好，且有氧條件之下5％雞毛粉組的總胺基酸濃度在試驗進行30天後達16.06 g/l 為最高，且個別胺基酸濃度在試驗期中均有上升之趨勢。雖然於試驗開始時有調整pH值，但THSC-1菌株試驗期間的pH值在培養第6日即達到穩定的7.0左右，且不同組別差異不大。 B. licheniformis THSC-1菌數在有氧下以含1 ％ 雞毛粉組為最高，在試驗進行30日之後，菌數仍有2.40 × 106 CFU/ml，且此組殘存雞毛乾重的百分率只有13.84 ％ ，為8個實驗組中分解雞毛比例最多的一組。試驗並製作引子 (primer) 以進行角蛋白分解?基因的純化，由電泳過程後證實此菌有1.4 kb長度的角蛋白分解?基因。 篩選出具角蛋白分解?的菌株THSC-1，並找出最適生長與最有利於分解雞毛條件後，希望能利用在家禽屠宰後雞毛的分解上，以使營養再生並解決廢棄物問題，因而達到永續經營的目的。 Waste disposal has become a problem as animals were intensively produced. Over three hundred million chickens were slaughtered in Taiwan at 1997, and their feathers were mostly underutilized because the Keratin made it poorly digestible. Currently, feathers were treated as waste or used as protein supplement for animal feedstuffs. Usually it required significant amount of energy to hydrolyse the peptide bonds linking the amino acid. Semi-degraded feather were taken from aerobic chicken manure and incubated in solid and liquid-phase hammer-milled-feather medium at 50 ℃ . Sixteen strains of bacteria were isolated after three generations, and no mold and yeast were found. The isolated bacteria named Bacillus licheniformis THSC-1 and the best incubated conditions were at pH 8.5 and 50℃ for decaying chicken feather. The total amino acid concentration of culture liquid inoculated with B. licheniformis THSC-1 under aerobic condition. It produced highest total amino acid concentration 16055 mg/l, when 5 ％ feather powder was added to culture liquid. We have found the best way for B. licheniformis THSC-1 to degrade chicken feather. we also used the PCR protocal to clone the keratinase gene.
