Efecto antagonista in vitro de bacillus spp sobre hongos filamentosos asociados a la fermentación del cacao (theobroma cacao l.)

The objective of this research was to control, in vitro conditions, the growth of filamentous fungi associated with the fermentation of cocoa through the application of Bacillus spp. The fungal isolates were obtained from samples of cocoa beans from four collection centers in the Calceta parish of Bolívar canton. They were isolated, purified and morphologically identified by means of a wet chamber technique and preparation of sheets with lactophenol blue. The strains of Bacillus spp. Were taken from the molecular Biology Laboratory of ESPAM MFL, five strains of B. subtilis (21BMC, 20BP, E-54, 50BP and 31BMC) and a strain of B. licheniformis (E-44) were used that were applied in doses of 100 and 200 μL in each variant. The experiment was conducted with a Completely Random Design and five replicas. The in vitro antagonism assays were performed in 90 x 16 mm Petri dishes with PDA medium adjusted to a pH of 7 and autoclaved at 15 psi/15 min. Four strains of fungi were identified, three of Aspergillus and one of Penicillium spp. The strains that showed the highest % inhibition were B. subtilis 31BMC on the strains of Aspergillus spp (74.43%), and B. licheniformis E-44 on the strain of Penicillium spp (76.96%), regardless of the dose of application. It is concluded that the strains of B. subtilis 31BMC and B. licheniformis E-44 are promising microorganisms for the control of filamentous fungi associated with the fermentation of cocoa.

• Main Author: Cedeño Alcívar, Diana Carolina (author)
• Other Authors: Vera Macías, Lenin Antonio (author)
• Format: masterThesis
• Language: spa
• Published: 2019
• Subjects: OTA; Poscosecha de Cacao; Aislamiento; Enfrentamiento Dual
• Online Access: http://repositorio.espam.edu.ec/handle/42000/1057