Winery wastewater arising from different wine production phases poses a
significant environmental threat and economic burden for wine producers
considering the legislative requirements regarding the obligatory wastewater
treatment. Taking into account the high amount of organic and inorganic
nutrients suitable for microbial growth being present in the winery
wastewater, the aim of this study was to investigate a possible valorisation
route for barrel washing winery wastewater through production of microbial
biocontrol agents based on Bacillus sp. The produced biocontrol agents were
tested against bacterial and fungal plant pathogens, including Xanthomonas
campestris, Xanthomonas euvesicatoria and Aspergillus flavus. The results of
in vitro antimicrobial activity testing have shown the high potential of
barrel washing winery wastewater to be used as substrate for Bacillus sp.
growth, considering that inhibition zone diameters of biocontrol agents
based on waste substrate were even higher compared to commercial synthetic
medium in case of Aspergillus flavus suppression. This study opens a
possibility to further optimize bioprocess conditions including valorisation
of barrel washing winery wastewater to maximize antimicrobial activity of
the produced biocontrol agents and contribute to the increase of
cost-effectiveness of both wine and biocontrol agent?s production.