Development and characterization of a transdermal patch and an emulgel containing kanamycin intended to be used in the treatment of mycetoma caused by Actinomadura madurae

Background: Mycetoma is a chronic, degenerative, and incapacitating infection of the skin and subcutaneous tissue. Aim: This study focuses on developing a kanamycin-based auxiliary system intended to be used in the treatment of mycetoma caused by Actinomadura madurae. Methods: Transdermal patches (with two different formulations: one with free kanamycin [K] and the other one with kanamycin adsorbed in silica [K-SG]) and an emulgel were developed. Both patches were prepared by the casting-evaporation technique. To characterize them, differential scanning calorimetry, bioadhesion, post-moisture detachment, strength and rupture distance, gas exchange, water uptake, and dissolution studies were carried out. The emulgel (containing 0.57% of kanamycin) was prepared from an oil-in-water emulsion, which was then incorporated to a gel. Results: the patches with the best characteristics contained 22.9% of silica and 14.6% of kanamycin. Dissolution studies indicated that 8.8% of kanamycin released from K and 3.2% from K-SG at 24h. The emulgel containing 0.57% of kanamycin showed good technological characteristics for its application to the skin (viscosity, 44.9 ± 1.4 poises; pH, 6.9 ± 0.4; and penetrability, 52.7 ± 5.1). Conclusions: The optimal patches were those containing 15.9% of freely dispersed kanamycin (K) and 14.6% of kanamycin adsorbed in silica (K-SG), which corresponds to the batch 2-0.8. The assessments performed to both pharmaceutical forms (patches and emulgel) show that they have the adequate technological characteristics for being used as an auxiliary in the treatment of actinomycetoma caused by A. madurae.     

马杜拉放线菌（Actinomadura sp.）FXJ1.344发酵产物的分离鉴定与活性分析

分离鉴定来源于江西酸性红壤中的马杜拉放线菌（Actinomadura）FXJ1.344所产生的次级代谢产物,并对其中生物活性物质进行分析。采用无水乙醇提取放线菌FXJ1.344发酵菌丝体,粗提物依次用硅胶柱层析法和凝胶柱层析法分离纯化,高效液相色谱法进行制备,并采用超高效液相色谱串联质谱法和核磁共振分析鉴定化合物结构。最终得到2个纯化物,分别为6-hydroxytetrangulol和tetrangulol。用滤纸片扩散法和对倍稀释法检测其抑菌活性,结果表明这2个纯化物均有较好的抗藤黄微球菌（Micrococcus luteus）活性,其最小抑菌浓度分别为3.90 μg/mL和15.6 μg/mL。