Endophytic Nocardiopsis sp. from Zingiber officinale with both antiphytopathogenic mechanisms and antibiofilm activity against clinical isolates

Novel and potential antimicrobial compounds are essential to tackle the frequently emerging multidrug-resistant pathogens and also to develop environment friendly agricultural practices. In the current study, endophytic actinomycetes from rhizome of Zingiber officinale were explored in terms of its diversity and bioactive properties. Fourteen different organisms were isolated, identified and screened for activity against Pythium myriotylum and human clinical pathogens. Among these, Nocardiopsis sp. ZoA1 was found to have highest inhibition with excellent antibacterial effects compared to standard antibiotics. Remarkable antibiofilm property was also shown by the extract of ZoA1. Its antifungal activity against Pythium and other common phytopathogens was also found to be promising as confirmed by scanning electron microscopic analysis. By PCR-based sequence analysis of phz E gene, the organism was confirmed for the genetic basis of phenazine biosynthesis. Further GC-MS analysis of Nocardiopsis sp. revealed the presence of various compounds including Phenol, 2,4-bis (1,1-dimethylethyl) and trans cinnamic acid which can have significant role in the observed result. The current study is the first report on endophytic Nocardiopsis sp. from ginger with promising applications. In vivo treatment of Nocardiopsis sp. on ginger rhizome has revealed its inhibition towards the colonization of P. myriotylum which makes the study to have promises to manage the severe diseases in ginger like rhizome rot.