利用大孔吸附树脂提取吸水链霉菌BS-112菌株的抗真菌活性物质

吸水链霉菌(Streptomyces hygroscopicus)BS-112菌株产生的活性物质对白僵菌、绿僵菌、黄曲霉菌等家蚕病原真菌具有抑制作用。研究了7种大孔吸附树脂对BS-112菌株产生的抗真菌活性物质的吸附和解吸性能,筛选出对抗真菌活性物质具有良好吸附及解吸性能的X-5树脂,这种树脂对抗真菌活性物质的饱和吸附量为73.37 mg/g,最适吸附温度为25℃,饱和吸附时间为150 min,以75%乙醇进行动态解吸,解吸率可达93.68%。BS-112菌株产生的抗真菌活性物质在低浓度下即能够较好地抑制家蚕病原白僵菌的生长,96孔板法测定的最小抑菌浓度(MIC)和杀菌浓度(MFC)分别为1.56、3.13μg/mL,并且活性物质的毒性小,以2 000 mg/kg剂量的活性物质灌胃小鼠,小鼠无急性中毒表现。

Extraction of Antifungal Active Substance from Streptomyces hygroscopicus BS-112 by Macroporous Adsorbent Resin

Active substance from Streptomyces hygroscopicus BS-112 has significant inhibitory effect on the pathogenic fungi of silkworm,such as Beaureria bassiana,Nomuraea rileyi,Aspergillus flavus etc.This paper studied the adsorption and desorption properties of 7 types of macroporous adsorbent resins to antifungal active substance from S.hygroscopicus BS-112.X-5 resin offered the best adsorption and desorption capacity for antifungal active substance.Its saturated absorption capacity was 73.37 mg/g.The optimal temperature for absorption was 25 ℃ and it took 150 min to achieve saturation adsorption.The opti-mal elution solution was 75% ethanol and the desorption rate could reach 93.68%.The antifungal active substance from BS-112 strain could well inhibit the growth of silkworm pathogen B.bassiana at low concentration.Assay using a 96-well plate illustrated that the minimum inhibitor concentration(MIC) and minimum antifungal concentration(MFC) of active substance against B.bassiana were 1.56 and 3.13 μg/mL,respectively.Nevertheless,the active substance had low toxicity.The administration of this substance to mouse at the dose of 2 000 mg/kg body weight for 14 days did not cause any apparent acute toxicity.