Albocycline, the main bioactive compound from Propionicimonas sp. ENT-18 against Sclerotinia sclerotiorum

•We elucidate the active compound of Propionicimonas sp. ENT-18.•Increasing information will enhance its biological control effectiveness.•We report the albocycline-production by a non-streptomycete.

The main aim of this study was to identify the active compound produced by the ant ectosymbiont Propionicimonas sp. ENT-18 against Sclerotinia sclerotiorum. An ethyl acetate whole extract from ENT-18 fermented broth was fractionated on Sephadex and Fluorisil columns prior to Q-TOF mass spectrometry analysis. The active fraction was found to contain the macrolide albocycline, which was deduced by interpreting the magnetic resonance data. Low concentration (1.6 μg/sclerotium) of the purified albocycline was sufficed to inhibit the sclerotia germination. Albocycline was considered as the main active molecule produced by ENT-18 against S. sclerotiorum. This is the first report of albocycline produced by a non-streptomycete and of its potential as an antimold molecule.