6533b855fe1ef96bd12b0aa0
RESEARCH PRODUCT
Plasma modified PLA electrospun membranes for actinorhodin production intensification in Streptomyces coelicolor immobilized-cell cultivations
Alberto SuteraGiuseppe GalloRoberto ScaffaroLuigi BottaFrancesco LoprestiRm Fontanasubject
0301 basic medicinePolyestersSegmented filamentous bacteriaS. coelicolor immobilizationAnthraquinonesStreptomyces coelicolor02 engineering and technologySecondary metaboliteSettore BIO/19 - Microbiologia GeneraleActinorhodinMicrobiology03 medical and health scienceschemistry.chemical_compoundColloid and Surface Chemistrystomatognathic systemPolylactic acidmedicinePlasma treatmentPhysical and Theoretical ChemistryIncubationMyceliumbiologyElectrospinningPhotoelectron SpectroscopyProdigiosinStreptomyces coelicolorActinorhodin productiontechnology industry and agricultureSettore ING-IND/34 - Bioingegneria IndustrialePLA membraneSurfaces and InterfacesGeneral Medicine021001 nanoscience & nanotechnologybiology.organism_classificationAnti-Bacterial Agents030104 developmental biologyMembraneSettore ING-IND/22 - Scienza E Tecnologia Dei MaterialichemistryBiochemistryMicroscopy Electron Scanning0210 nano-technologyBiotechnologymedicine.drugdescription
Most of industrially relevant bioproducts are produced by submerged cultivations of actinomycetes. The immobilization of these Gram-positive filamentous bacteria on suitable porous supports may prevent mycelial cell-cell aggregation and pellet formation which usually negatively affect actinomycete submerged cultivations, thus, resulting in an improved biosynthetic capability. In this work, electrospun polylactic acid (PLA) membranes, subjected or not to O2-plasma treatment (PLA-plasma), were used as support for immobilized-cell submerged cultivations of Streptomyces coelicolor M145. This strain produces different bioactive compounds, including the blue-pigmented actinorhodin (ACT) and red-pigmented undecylprodigiosin (RED), and constitutes a model for the study of antibiotic-producing actinomycetes. Wet contact angles and X-ray photoelectron spectroscopy analysis confirmed the increased wettability of PLA-plasma due to the formation of polar functional groups such as carboxyl and hydroxyl moieties. Scanning electron microscope observations, carried out at different incubation times, revealed that S. coelicolor immobilized-cells created a dense âbiofilm-likeâ mycelial network on both kinds of PLA membranes. Cultures of S. coelicolor immobilized-cells on PLA or PLA-plasma membranes produced higher biomass (between 1.5 and 2 fold) as well as higher levels of RED and ACT than planktonic cultures. In particular, cultures of immobilized-cells on PLA and PLA-plasma produced comparable levels of RED that were approximatively 4 and 5 fold higher than those produced by planktonic cultures, respectively. In contrast, levels of ACT produced by immobilized-cell cultures on PLA and PLA-plasma were different, being 5 and 10 fold higher than those of planktonic cultures, respectively. Therefore, this is study demonstrated the positive influence of PLA membrane on growth and secondary metabolite production in S. coelicolor and also revealed that O2-plasma treated PLA membranes specifically promoted higher ACT production than not treated membranes.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2017-09-01 |