https://doi.org/10.17113/ftb.57.02.19.6139        


Survival of Spray-Dried Rhodotorula mucilaginosa Isolated from Natural Microbiota of Murta Berries and Antagonistic Effect on Botrytis cinerea  


Alexandra González-Esparza^1,2*, Juan Carlos Gentina¹, Kong S. Ah-Hen², Roxana Alvarado³, Joaquín Stevenson², Erika Briceño⁴ and Osvaldo Montenegro<sup>4  


1</sup>School of Biochemical Engineering, Faculty of Engineering, Pontifical Catholic University of Valparaíso, Avenue Brasil 2085, 2340000 Valparaíso, Chile 
²Institute of Food Science and Technology, Faculty of Agricultural Sciences, Austral University of Chile, Avenue Julio Sarrazín sn, Campus Isla Teja, 5090000 Valdivia, Chile 
³Institute of Biochemistry and Microbiology, Faculty of Sciences, Austral University of Chile, Avenue Julio Sarrazín sn, Campus Isla Teja, 5090000 Valdivia, Chile 
⁴Institute of Plant Production and Health, Faculty of Sciences, Austral University of Chile, Avenue Eduardo Tallman sn, Campus Isla Teja, 5090000 Valdivia, Chile  



Article history:  
Received: 20 November 2018 
Accepted: 26 March 2019
 



Key words:  
dehydration, yeast, grey mould, phytopathogenic fungus, antagonistic activity, biocontrol  



Summary: 
The aim of this study is to evaluate the survival rate and effective antagonistic activity against Botrytis cinerea, responsible for grey mould on harvested fruits and vegetables, of yeast Rhodotorula mucilaginosa, isolated and identified from the natural microbiota of murta (Chilean guava) berries, after spray drying at different inlet air temperatures, mass per volume ratio of encapsulating agent (maltodextrin) and feed flow rates. The 100 % survival of the yeast was obtained after spray drying with 18 % maltodextrin at 130 °C inlet temperature and a feed flow rate of 9.25 mL/min. The dried yeast obtained under such conditions had the highest antagonistic activity in vitro and in vivo on apples, which showed that spray drying is a valid method to produce active dried cells of R. mucilaginosa that can be used for biocontrol of grey mould spoilage. It was also found that the encapsulating agent maltodextrin improved the in vitro antagonistic activity of R. mucilaginosa.   




*Corresponding author:    +56989312256
                                              alexandra.gonzalez@gmail.com