Addition of a mixed Bacillus assemblage to commercial banana weaning tanks results in latex remediation, extended tank water viability and a reduction in post-harvest disease

Post-harvest banana hands are cut into segments of three to eight fingers for export, a process which causes the release of latex from laticiferous ducts in the crown. This issue has traditionally been addressed through weaning, a process requiring large volumes of fresh water. Addition of a Bacillus assemblage (Bacillus subtilis, B. licheniformis and B. pumilus serotypes) to weaning tanks during field trials at a commercial banana processing facility in Costa Rica (CORBANA) resulted in remediation of banana latex, improved water quality in weaning tanks, improved control of fecal coliforms in tank water and a reduction in post-harvest diseases among bananas. In vitro assays were conducted with each of the bacterial isolates, screening them for enzymatic activity relevant to latex remediation, as well as for antibacterial and antifungal activity. Results showed that these isolates were capable of degrading a number of the components known to makeup banana latex. Soft-agar overlays (bacterial inhibition) and plate screenings (fungal inhibition) revealed inhibitory properties among the Bacillus isolates. Use of this Bacillus assemblage in banana weaning tanks has the potential to decrease water usage in banana processing facilities, as well as reducing the incidence and severity of post-harvest diseases in bananas.