地锦草有效部位对真菌琥珀酸脱氢酶活性的影响

目的初步研究维吾尔药材地锦草有效部位体外抗真菌作用，研究地锦草有效部位对红色毛癣菌琥珀酸脱氢酶活性的影响，探讨其抗真菌作用机制。方法地锦草醇提物经大孔吸附树脂分离得6个洗脱部位，分别为部位一、部位二、部位三、部位四、部位五及部位六；采用微量液基稀释法测定各部位体外最低抑菌浓度（MIC）值，确定其最有效部位和敏感菌株；药物干预毛癣菌后分离菌体，按试剂盒要求处理样品，利用硫酸甲酯吩嗪（PMS）反应法，测定地锦草有效部位对红色毛癣菌琥珀酸脱氢酶活性的作用。结果地锦草各洗脱部位中，部位六的抗真菌活性最为显著，其对红色毛癣菌（T．rubrum）的平均MIC为149μg／mL，对石膏样毛癣菌（T．mentagrophytes）的平均MIC为149μg／mL，对其他皮肤癣菌平均MIC为192μg／mL，对4种念珠菌的平均MIC均为416μg／mL。不同浓度的地锦草有效部位均可降低红色毛癣菌琥珀酸脱氢酶活性（P〈0．01）。结论地锦草不同提取部位对试验菌株的生长均具有抑制作用，其中部位六尤为显著，对浅部致病真菌有较强的抑制作用，定为有效部位。地锦草有效部位抗真菌机制可能与抑制琥珀酸脱氢酶的活性有关。

Effect of Active Component of Euphorbia Humifusa on SDH of Trichophyton rubrum

Objective： To study the antifungai activity of different extraction fractions from Euphorbia humifusa in vitro, and study the effect of active component of Euphorbia humifusa on SDH of T. rubrum. Methods Six extraction fractions of Euphorbia humifusa were obtained by eluting the original extraction with macroporous resin column using gradient elution separation method and were assayed with micro-broth dilution technique in order to determine their minimum inhibitory concentrations against 24 sensitive strains. T. rubrum was treated with active component of Euphorbia humifusa, and the effects on SDH activity in T. rubrum was studied by PMS test. Results All of the six extraction fractions from Euphorbia humifusa showed antifungal activity in vitro. MIC of fraction VI was 149 μg/mL. On T. rubrum, 149 μg/mL on T. mentagrophytes, 192 μg/mL on other dermatophytes, and 416 μg/mL on 4 kinds of candida. The PMS test results showed that squaiene epoxidase activity decreased significantly （P 〈0.01） in T. rubrum when the concentration of active component of Euphorbia humifusa was in a does dependent manner. Conclusion Active component of Euphorbia humifusa has significant antifungal activity, and the fraction VI of Euphorbia humifusa was seem as the active component of Euphorbia humifusa. The antifungal mechanism may be related to its inhibition on SDH activity.