本文研究了菌龄、酶浓度、酶解时间、酶解pH、温度、渗透压稳定剂及青霉素对枯草芽孢杆菌DC-12原生质体形成和再生的影响。确定了DC-12原生质体最佳的形成和再生条件是以改良HM高渗溶液作稳渗系统，在pH 7.5、酶浓度为0.2 mg/ml（活力单位为50000 U/g）和35 ℃的条件下酶解60 min；此条件下所得原生质体形成率为96.1%；以0.6 mol/L NaCl为渗透压稳定剂的DM3再生培养基中再生率为21.6%。

The effects of different factors, such as age, lysozyme dosage, enzymatic time, the pH value, temperature, osmotic stabilizer, and penicillin, on protoplast formation and regeneration of Bacillus strains DC-12 were studied. The most suitable hypertonic buffer, culture time, pH value, lysozyme dosage, reaction temperature and time were HM hypertonic buffer, 7.5, 2.0 mg/mL, 37 ℃ and 60 min, respectively, with which the rate of protoplast formation and regeneration were 95.8%. If 0.6 mol/L NaCl was used as the regeneration hypertonic buffer, the rate of protoplast formation and regeneration was 21.6%.