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Organosolv treatment for prebiotic oligosaccharide production from agro-food waste için kapak resmi
Organosolv treatment for prebiotic oligosaccharide production from agro-food waste
Başlık:
Organosolv treatment for prebiotic oligosaccharide production from agro-food waste
Yazar:
Temelli, Nuran, author.
Yazar Ek Girişi:
Fiziksel Tanımlama:
viii, 68 leaves: color illustrarions, charts;+ 1 computer laser optical disc.
Özet:
Xylooligosaccharides (XOS), which are among the prebiotic carbohydrates, are produced by hydrolysis of xylan in the lignocellulosic agricultural and food wastes. Production processes, such as autohydrolysis and enzymatic hydrolysis following alkali extraction, have some limitations. In this study, it was aimed to develop a process that could overcome those limitations. Corn cob was used as the model biomass and it was pretreated with organosolv. The organosolv pretreatment conditions (solvent concentration, time, temperature, catalyst addition) were adjusted to maximize the lignin removal from the biomass while recovering xylan in the biomass. Delignification could be achieved with 40%-50% lignin removal, and around 85% of the xylan was retained in the biomass. The effect of the organosolv conditions on XOS formation was investigated by the hydrolysis of the pretreated biomass using three commercial xylanases. The organosolv and the enzymatic hydrolysis conditions influenced the XOS formation. The maximum XOS production was observed with the biomass pretreated at 150°C for 1 h with 70% ethanol and 0.1 M MgO. That biomass was enzymatically hydrolyzed at 70°C with 0.6 U/ml xylanase and 70% of the xylan was converted to XOS yielding a hydrolysate containing 9.5 g/l XOS. With the process developed in this study, the need for the application of concentrated alkaline and acidic solutions can be eliminated since the xylan extraction step is not needed. In addition to that, the formation of carbohydrate degradation products can be avoided due to the lower treatment temperatures compared to autohydrolysis. These can simplify the downstream processing following the production of XOS and minimize the environmentally harmful chemical wastes. In this process, a liquid stream rich in lignin and a solid stream rich in cellulose were released. Following a biorefinery concept, these streams can potentially be valorized together with the xylan, so that lignocellulosic wastes can have an added value. This study will be followed by related projects on XOS purification and determination of the prebiotic potential of XOS. In addition to that, the process developed will be tested on other lignocellulosic wastes.
Yazar Ek Girişi:
Tek Biçim Eser Adı:
Thesis(Master)-- İzmir Institute of Technology: Food Engineering.

İzmir Institute of Technology: Food Engineering--Thesis (Master).
Elektronik Erişim:
Access to Electronic Versiyon.
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