Učinak reciklacije lignocelulolitičkih enzima na proizvodnju lipida s kvascem Trichosporon oleaginosus uzgojenim na hidrolizatu kukuruznog oklaska

undergraduate thesis

• Title (english): The effect of lignocellulosic enzymes recycling on lipid production by yeast Trichosporon oleaginosus grown on corn cob hydrolysate
• Author: Ana-Marija Gruičić
• Mentor: Mirela Ivančić Šantek (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2017-09-18, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Mikrobni lipidi, proizvedeni uz pomoć oleaginoznih mikroorganizama na lignoceluloznim supstratima, obećavajuća su alternativa nafti kao sirovina za proizvodnju dizela. Oleaginozni kvasac Trichosporon oleaginosus može nakupiti i do 80% lipida u biomasi prilikom rasta u uvjetima limitacije dušikom. Mikrobna proizvodnja lipida uključuje hidrolizu lignocelulozne sirovine do fermentabilnih šećera, koji se koriste za mikrobni rast i sintezu lipida. U ovom radu prikazan je novi proces odvojene hidrolize i proizvodnje lipida uz reciklaciju enzima, koji je proveden u četiri ponovljena ciklusa. Nehidrolizirani, teško razgradivi čvrsti ostatak s adsorbiranim celulazama, izdvojen je i nanovo korišten u narednim ciklusima enzimske hidrolize. Dobiveni rezultati pokazali su da se reciklacijom nehidrolizirane biomase u četiri ciklusa smanjuje dodana količina enzima do 30% njegove optimalne količine, bez značajnijeg utjecaja na učinkovitost hidrolize lignocelulozne sirovine i produktivnost nakupljanja lipida. Prosječna vrijednost koncentracije biomase iznosila je 23,23 gL-1, a udio lipida u biomasi 47,58 %.

Abstract (english)

Microbial lipids produced from lignocellulosic biomass by oleaginous microorganisms are promising alternative feedstock to petroleum in biodiesel production. Oleaginous yeast Trichosporon oleaginosus has the ability to accumulate lipids up to 80% of the biomass under nitrogen-limited growth conditions. Microbial lipid production involves hydrolysis of lignocellulosic biomass into fermentable sugars, which are used for microbial growth and lipid synthesis. Here we report a novel process of the separate hydrolysis and lipid production with enzyme recycling conducted in four repeated cycles. Unhydrolysed recalcitrant solids with adsorbed cellulases were separated and recycled to the subsequent cycles of enzymatic hydrolysis. Obtained results indicated that enzyme recycling with the unhydrolysed solids reduced the enzyme loading up to 30% of the optimal enzyme loading without significant effect on efficiency of lignocellulose hydrolysis and lipid productivity. Average value of biomass concentration and lipid content was 23,23 gL-1 and 47,58 %, respectively.

• Keywords: biodizel; celulaze; lignoceluloza; lipidi; oleaginozni mikroorganizmi
• Keywords (english): biodiesel; cellulases; lignocellulose; lipid; oleaginous microorganisms
• Language: croatian
• URN:NBN: urn:nbn:hr:159:224478
• Study programme: Title: Biotechnology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-09-20 07:26:59