title: A high-performance molluscicidal ingredient against Oncomelania hupensis produced by a rhizospheric strain from Phytolacca acinosa Roxb.
abstract: BACKGROUND
  Snail (Oncomelania hupensis) control is an important and effective preventive strategy in schistosomiasis control programs, and screening microbial molluscicidal agents is one of the most promising categories in biomolluscicides.
  
  
  OBJECTIVE
  To purify and identify the molluscicidal ingredient (MI) obtained from strain SL-30's exocellular broth.
  
  
  METHODS
  The active extracts extracted from SL-30's exocellular broth was purified on a silica gel column guided by molluscicidal activity assay against Oncomelania hupensis, then the MI was obtained. NMR spectroscopy and LC-MS/MS analysis was used to identify the molecular structure of the MI.
  
  
  RESULTS
  Molluscicidal activity bioassay showed that the MI exhibited significant molluscicidal activity with the LC(50) values of 0.101, 0.062, and 0.022 mg/L, respectively, in the case of exposure period of 24 h. From (1)H NMR, (13)C NMR, (1)H-(1)H COSY, and (1)H-(13)C HSQC spectra, partial important structure fragment was obtained, and the relative molecular weight of the MI showed 326 according to LC-MS analysis. Then, on these grounds, it was indicated that the molecular structure of the MI had a higher similarity to Gliotoxin with the molecular formula of C(13) H(14)N(2)O(4)S(2). The quasi-molecular ion of m/z 325.45 was further analyzed by MS(2) as the parent ion, and two daughter ions obtained at m/z 295.11 [M-CH(2)OH]- and m/z 261.08 [M-CH(2)OH -2S]-
  
  
  CONCLUSIONS
  The MI was finally confirmed as Gliotoxin.
authors.affiliation: School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China.
authors.forename: Danzhao
authors.initials: D
authors.lastname: Guo
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Yidan
authors.initials: Y
authors.lastname: Liu
authors.forename: Hu
authors.initials: H
authors.lastname: Yao
authors.forename: Fang-An
authors.initials: FA
authors.lastname: Han
authors.forename: Jing
authors.initials: J
authors.lastname: Pan