Antimicrobial activities of isoalantolactone, a major sesquiterpene lactone ofInula racemosa

Isoalantolactone, a major constituent of Inula racemosa (Compositae) was tested for its antimicrobial action against five bacteria, six human and six plant pathogenic fungi. The lactone showed absolute toxicities at 500 m g/mL against 3 soil borne phytopathogenic fungi (Gaeumannomyces graminis var. tritici, Rhizoctonia cerealis and Phytophthora capsici) with the MICs determined to be 100, 100 and 300 m g/mL, respectively. At the MICs, isoalantolactone exhibited its fungistatic nature of toxicity. The lowest fungicidal concentrations of the lactone to G. graminis var. tritici, R. cerealis and >. capsici were shown to be 150, 150 and 350 m g/mL, respectively. Moreover, isoalantolactone displayed weaker antibacterial activities against Bacillus subtilis, Escherichia coli, Pseudomonas fluorecense, Sarcina lentus and Staphylococcus aureus with MICs of 125, 425, 150, 150 and 100 m g/mL, respectively. The investigation disclosed the strong inhibition of isoalantolactone to the phytopathogenic fungi, raising a possibility that the lactone could be considered as a starting point for the project aiming at the development of new fungicide(s).     

栽培土木香酯类成分的对比测定

在本文中分析了栽培土木香中土木香内酯和异土木香内酯的含量,为栽培土木香药材质量控制提供依据.研究表明:该方法适合栽培土木香药材中土木香内酯和异土木香内酯含量的分析,可以作为栽培土木香药材质量控制的定量方法.