RESUMO
In this work, the effectiveness of different enzymatic techniques for cell wall disruption of Haematococcus pluvialis for the extraction of carotenoids and subsequent encapsulation of extracts in the co-polymer poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) using the Solution Enhanced Dispersion by Supercritical fluids (SEDS) technique was investigated. Glucanex(®) performed best compared with Lyticase(®) and Driselase(®). The conditions for enzymatic lysis using this enzyme preparation were established as a pH of 4.5, a temperature of 55 °C, an initial activity of ß-1,3-glucanase of 0.6 U mL(-1) and a reaction time of 30 min. Enzymatic lysis assisted by ultrasound without biomass freezing was shown to be a promising and simple one-step technique for cell wall disruption, reaching 83.90% extractability. In the co-precipitation experiments, the highest encapsulation efficiency (51.21%) was obtained when using a higher biomass to dichloromethane ratio (10 mg mL(-1)) at the carotenoid extraction step and a lower pressure of precipitation (80 bar). In these conditions, spherical particles in the micrometer range (0.228 µm) were obtained.
Assuntos
Células Imobilizadas , Clorófitas/química , Antioxidantes/metabolismo , Biomassa , Biotecnologia/métodos , Cromatografia Líquida de Alta Pressão , Temperatura Alta , Xantofilas/química , Xantofilas/isolamento & purificaçãoRESUMO
Las enfermedades prion son un grupo se desordenes degenerativos del sistema nervioso central que comparten características patológicas crónicas y progresivas. Los agentes causales son un grupo de proteínas infectantes sin presencia de ácidos nucleicos. El objetivo de realizar esta revisión es dar a conocer: qué son las enfermedades priónicas, además de aportar datos sobre su fisiopatología, clasificación, modos de transmisión a si como cuadro clínico, diagnóstico y posible tratamiento para lograr una mayor comprensión de estas patologías. Normalmente en nuestro organismo existen proteínas llamadas proteínas priónicas (PrP) las mismas que poseen un nivel de estructuración de tipo hélice alfa que es susceptible a la lisis por proteasas; la patogénesis de estas proteínas se producen cuando aparece una mutación o un cambio conformacional inducido por PrP patógena de otro individuo lo cual altera su estructura tridimensional haciendo imposible su lisis enzimática y su consecuente acumulación en los tejidos afectados, originando así las enfermedades priónicas.
The prion diseases are a group of degenerative disorders of the central nervous system that have chronic and progressive pathological characteristics in common. These diseases are caused by infectious agents called prion. A prion is a small proteinaceous infectious particle which resists inactivation by procedures that modify nucleic acids. The objective of this article is to understand the different aspects of these diseases and to contribute data about its physiopathology, classification, clinical signs and symptoms, diagnosis and treatment to. There exists a cellular protein known as cellular prion protein PrP that have alpha helix structure susceptible to lysis by protease. The pathogenesis of these proteins are produced when the mutation causes a change in the folding pattern of these protein which makes it resistant to the action of proteases and causes it to precipitate as insoluble amyloid. It accumulates in the affected tissue and causes the disease.