“Nejayote” valorization as a culture medium for Pseudomonas fluorescens and production of antifungal extracts

Abstract

Background / Objetive. Nejayote is an alkaline agroindustrial waste that is generated from the nixtamalization process of corn. The purpose of this work was to demonstrate that nejayote can be used as a culture medium for the growth of Pseudomonas fluorescens NR113647 and to produce metabolites with antifungal activity for the sustainable management of Aspergillus niger, Botrytis cinerea and Fusarium solani. Materials and Methods. Culture media were formulated with nejayote and nejayote with glycerol, with pH 6 and 12. The bacterial biomass was separated by centrifugation and filtration and the antifungal capacity of the extracts against A. niger, B. cinerea and F. solani was determined. The determination of the metabolites present in the extracts was carried out. P. fluorescens NR113647 was able to grow on all media. Results. The extracts from nejayote at pH 12 showed inhibition of the growth of all the fungi evaluated; at least five metabolites produced by P. fluorescens NR113647 and involved in the biocontrol of phytopathogens were identified. Conclusion. Nejayote can be used as a culture medium for P. fluorescens NR113647, to produce biomass and secondary metabolites with antifungal capacity; in addition, nejayote could be used for the cultivation of other microorganisms.