RESUMEN
Purpose: Pulmonary tuberculosis (TB) is a worldwide life-threatening infection. Therecommended anti-TB regimen contains oral administration of classical first-line drugs suchas rifampin for 6-24 months which often leads to low patient compliance due to high adverseeffects; therefore, lung localized pulmonary delivery of anti-TB agents may be a suitablealternative. Proliposomes free-flowing powders are well-known carriers for lung delivery sincethey can form liposomes by hydration. Liposomes are safe and useful carriers for lung deliverydue to their phospholipid structure. Methods: Porous lactose and mannitol as proliposome carriers were prepared by spray dryingtechnique using sucrose and citric acid as templating agents. Design Expert® software wasused to develop forty formulations based on the porous and non-porous carriers, which werecharacterized with respect to their weight yield, density, and flowability. Rifampin-loadedhydrated liposomes were produced and evaluated for size, morphology, loading capacityand encapsulation efficiency. The optimized proliposomes in vitro release and aerosolizationproperties were evaluated. Solid-state analysis was confirmed by differential scanningcalorimetry (DSC). Results: Porous lactose surface area was 80 folds higher than non-porous one, respectively.Optimized porous-based proliposome indicated the acceptable aerosolization properties,including mass median aerodynamic diameter (MMAD) of 6.21 ± 0.36 µm and fine particlefraction (FPF) of 9.17 ± 0.18% with a fast rifampin release (80%) within one hour. DSC resultsproved that there was no change in the solid-state of rifampin during the production process. Conclusion: Hence, it seems; rifampin loaded inhalable proliposomes may be a suitable systemfor delivering liposomal rifampin into the lungs.
RESUMEN
Background: Yarrowia lipolytica is a nonconventional, dimorphic yeast with multiple biotechnological applications. Considering the size of Y. lipolytica cells and a plethora of its morphological forms (spherical cells or hyphae and pseudohyphae), it is highly difficult to select a suitable carrier for this useful microorganism. Bacterial cellulose (BC) is currently considered one of the most promising immobilization carriers. In the current study, the usefulness of oil- and emulsion-modified BCs as a carrier for Y. lipolytica immobilization was investigated. Static and agitated cultures were conducted in media supplemented with oil or emulsion to improve carrier porosity. Results: It was found that the application of oil- and emulsion-modified BCs correlated with significantly higher efficiency of Y. lipolytica immobilization and hence higher yield than the yield achieved with an unmodified carrier. Increased efficiency of immobilization correlated with BC porosity-related parameters, which, in turn, depended on the size of oil droplets introduced into the culture medium. Moreover, changes in porosity-related parameters caused by the addition of oil or emulsion to the medium were observed when the cultures were conducted only under static conditions and not under agitated conditions. Conclusion: The application of oil- and emulsion-modified BCs as carriers significantly increased the efficiency of Y. lipolytica immobilization as compared to unmodified BC. The addition of oil or emulsion to the culture medium can be a simple but effective method to modify the porosity of BC-based carriers.