INVESTIGADORES
DELGADO osvaldo Daniel
congresos y reuniones científicas
Título:
Isolation and identification of bacteria with potential phenoloxidase activity from olive wastes (alperujo) in the province of Catamarca.
Autor/es:
COLOMBETTI P; VERGARA R; DELGADO OD; FARIÑA JI
Lugar:
Mar del Plata
Reunión:
Congreso; VIII Congreso de Microbiologia General; 2012
Institución organizadora:
Sociedad Argentina de Microbiologia General
Resumen:
Alperujo is a solid-liquid olive waste with an
enormous organic load generated from the production of olive oil by the
two-phase method of olive oil extraction. This waste is rich in phenolic
compounds (98% of fruit phenolics have become part of the waste), most of which
are considered extremely toxic for plants and microorganisms. This justifies
the high polluting effect of waste and its incompatibility to be used as
compost. The aim of this work was to isolate and identify bacterial strains
with potential phenol oxidase activity (FOX) at different alperujo maturation
stages and also to evaluate the possibility of inactivating toxic polyphenols
remaining in this waste. Bacterial colonies isolated by direct streaking on LB solid medium were
incubated at 35°C for 72 h and maintained by successive streaks.
Micro-morphological characterization was performed by Gram-Nicolle differential
coloration, and Gram positive bacteria were heated in a water bath at 70°C
during 30 min in order to select sporulating bacteria. Isolaes were identified
by 16S rDNA sequence analysis. In situ FOX activity was revealed on R2A solid
minimal medium supplemented with 0.2% (w/v) tannic acid. After 96 h of
incubation, the dark brown coloration of the colony was considered positive. Phylogenetic
analysis showed that FOX activity-carrying bacteria are close related to
rod-shaped Gram positive bacteria (98-99% similarities) like Lysinibacillus fusiformis, Bacilllus cereus,
Bacillus pumilus and also with the rod-shaped Gram negative Pseudomonas aeruginosa and they could be
good candidates to degrade polyphenols from alperujo, and so detoxifying waste
generated by olive industry. Additionally, it was observed that Pseudomonas aeruginosa and Lysinibacillus fusiformis exhibited the
greatest persistence to colonizing alperujo at different maturation stages (or
edges), while Pseudomonas aeruginosa
showed the highest FOX activity.