Los polihidroxialcanoatos (PHAs) son poliésteres bacterianos acumulados como material de almacenamiento de carbono y energía en ambientes con desbalance Carbono/Nitrógeno ó Carbono/Fosforo, que han ido adquiriendo mayor importancia debido a su diversidad estructural y similitud con los plásticos. Su desventaja radica en sus elevados costos de producción que en gran parte se deben a la fuente de carbono utilizada, hecho que ha implicado la búsqueda de alternativas que minimicen su valor; razón por la cual en esta investigación se evaluó inicialmente la capacidad productora de PHAs de 160 bacterias silvestres presentes en el cepario del grupo de investigación ASUBAGROIN por medio de la técnica de tinción de Nilo Azul suplementado con glucosa,de las cuales 31 bacterias mostraron fluorescencia como indicativo de producción de PHAs y se continuo con la evaluación en sacarosa, lactosa y almidón; de este grupo solo 4 bacterias mostraron fluoresencia en los tres sustratos, posteriormente con el fin de corroborar que las bacterias seleccionadas son capaces de producir PHAs se realizó la prueba de Negro Sudan técnica que a través de la tinción de la pared lipídica de los granulos del biopolímero permitió elegir 3 bacterias que fueron identificadas molecularmente mediante el gen ribosómico ARNr 16s como Bacillus thuringiensis, Bacillus amyloliquefaciens y Serratia sp. microorganismos que fueron sometidos a una fermentación tipo batch donde la mayor producción de PHAs se obtuvo en glucosa (61,83%) seguido de lactosa (61,36%); sacarosa (58,77%) y almidón (30,30%). Finalmente, el polímero recuperado se caracterizó por cromatografía líquida de ultra alta precisión acoplado a espectrometría de masas (UHPLC-MS) y espectroscopia infrarroja (FTIR) donde los resultados determinaron que los compuestos resultantes de la fermentación realizada son Polihidroxibutirato-Polihidroxivalerato.
Polyhydroxyalkanoates (PHAs) are bacterial polyesters accumulated as carbon and energy storage material in environments with Carbon / Nitrogen, Carbon / Phosphorus imbalances that have become more important because of their structural diversity and similarity with plastics. Its main drawback lies in its high production costs, which are largely due to the carbon source used, a fact that has involved the search for alternatives that minimize its value; That is the reason why in this investigation the PHA production capacity of 160 wild bacteria was evaluated, these bacteria are present in the strain owned by the “Utilization of by-products and agroindustrial residues” group from the University of Cauca, this evaluation was made by means of the technique of Blue Nile staining supplemented with glucose, Of which 31 bacteria showed fluorescence, these were evaluated in sucrose, lactose and starch; From this group only 4 bacteria showed fluorescence in all three substrates, subsequently in order to corroborate that the selected bacteria were able to produce PHAs, these were tested by Black Sudan technique that through the staining of the lipid wall of the granules of the biopolymer which allowed to choose 3 bacteria that were identified molecularly by the ribosomal rRNA gene Bacillus thuringiensis, Bacillus amyloliquefaciens and Serratia sp, microorganisms that were submitted to a batch fermentation, where the highest production of PHAs was obtained in glucose (61.83%) followed by lactose (61.36%), sucrose (58, 77%) and starch (30.30%). Finally, the recovered polymer was characterized by Ultra High Precision Liquid Chromatography coupled to mass spectrometry (UHPLC-MS) and Infrared Spectroscopy (FTIR). The results of the characterization analyzes determined that the compounds resulting from the fermentation were Polyhydroxybutyrate-Polyhydroxyvalerate.
