PhD in Chemical and biochemical processes for the extraction and characterization of wood hemicelluloses - LGP2

Descrizione

PhD in Chemical and biochemical processes for the extraction and characterization of wood hemicelluloses - LGP2 Sintesi in italiano (traduzione automatica): Il progetto di dottorato si concentra sulla valorizzazione delle emicellulose legnose, costituendo una risorsa potenziale per la produzione di zuccheri rari. Le emicellulose rappresentano una parte significativa della biomassa vegetale e il progetto mira a sviluppare processi chimici e biochimici sostenibili per estrarre e caratterizzare oligomeri e monomeri di emicellulose. La sede del progetto è presso LGP2 e richiede una laurea in Chimica o un campo correlato. Le mansioni principali includono lo studio dei processi di estrazione e la caratterizzazione avanzata degli oligosaccaridi e polisaccaridi estratti. Il candidato ideale avrà competenze in chimica organica e biochimica, con un forte interesse per le applicazioni industriali delle emicellulose. The main objective of the project is to valorize wood hemicelluloses. Hemicelluloses constitute the second most important component in vegetal biomass, as they represent from 20 to 30% in mass of wood and annual plants. Hemicelluloses are complex polysaccharides, composed of two or three monomers (e.g. arabinoxylans; galactoglucomannans), that can partly be acetylated and that can contain lateral groups like methylglucuronic acid groups. They represent a potential resource for the production of some rare oligomeric or monomeric sugars. For example, hardwood hemicelluloses are mainly composed of arabinoxylans, which then give access to xylose. This latter is currently looked for as a precursor of furfural or xylitol for the chemical or the food industries. Softwood hemicelluloses are mainly of the galactoglucomannan type, that represent an interesting source of mannose or of oligomers of galactoglucomannans. Furthermore, it has been shown that oligosaccharides from hemicelluloses have interesting prebiotic properties for nutrition or medical applications, that could replace or improve current commercial prebiotics like fructo-oligosaccharides (FOS). Contrary to cellulose which is widely exploited in the paper and board, textile, material or chemistry industries, hemicelluloses are burned for the production of energy. Indeed, during the extraction process of cellulose, hemicelluloses are degraded and solubilized in the effluent of the process, called, the black, liquor. This liquor is concentrated and burnt to produce energy, which makes the paper pulp industry net producers of energy. This industry could thus afford to valorize hemicelluloses in higher added value product instead of using them to produce energy, without affecting the energy need of the industry. The potential quantities are huge when one knows that the pulp industry is currently using 300 million tons of wood globally. Our project aims at developing sustainable and combined chemical and biochemical processes that would be compatible with biorefineries integrated in the pulp industry, for the production of hemicelluloses oligomers or monomers, with specific properties and purity suitable for the different applications foreseen. The first part of the PhD thesis will study different processes to extract hemicelluloses from wood, combining chemical and biochemical processes. The second part will be devoted to advanced characterization of oligosaccharides and polysaccharides extracted Annuncio in inglese. Fonte: Euraxess (Commissione europea).