Enzymatic treatment lignocellulosic substrate for ethanol production

Enzimska hidroliza pulpe šećerne repe (PŠR), klipa kukuruza i drvnih ostataka provedena je u Erlenmeyer tikvicama na laboratorijskoj tresilici, korištenjem enzimskih otopina pripravljenih tijekom uzgoja Trametes multicolor, Sclerotium rolfsii i Neurospora crassa na različitim supstratima. Najbolji rezultati ostvareni su hidrolizom PŠR korištenjem enzimskih otopina Sclerotium rolfsi uzgojene na PŠR i celulozi. Optimalni uvjeti hidrolize u tikvicama na laboratoriskoj tresilici ostvareni su u vodenim otopinama s 66 g/L PŠR pri 40 oC, 150 okr/min i koncentraciji enzima od 5 ml/L. Povećanje koncentracije enzima nije pogodovalo povećanju koncentraciji reducirajućih šećera, ali je kombinacijom enzimskih otopina S1c i S1sb te dodatkom pulpe u obrocima tri puta po 22 g/L odnosno 44 g/L PŠR ostvareno povećanje koncentracije reducirajućih šećera na razinu pogodnu za proizvodnju bioetanola (52,46 g/L). Hidroliza PŠR provedena je i u bioreaktorima s lopatastim i turbinskim miješalom. Izmjerene koncentracije reducirajućih šećera bile su niže od prethodno izmjerenih tijekom eksperimenata u tikvicama na laboratoriskoj tresilici (16,0 g/L odnosno 25,00 g/L).Enzyme hydrolysis of sugar-beet pulp, corn cobs and wood residues was examined in Erlenmayer squash at laboratory shaker, using enzyme solution prepared during grow Trametes multicolor, Sclerotium rolfsii and Neurospora crassa on different substrates. The best results were achieved during hydrolysis of sugar-beet pulp with enzymatic solution of Sclerotium Rolfsii (S1sb and S1c). The optimum conditions of hydrolysis in the laboratory shaker on flasks were made in aqueous solutions with 66 g/L sugar-beet pulp on 40 °C, 150 rpm and concentration of enzymes of 5 g/L. Increasing the concentration of the enzyme did not influence on concentration of reducing sugars but with a combination of enzyme solution of S1c and S1sb and addition of sugar-beat pulp in three times repetition of 22 g/L and 44 g/L we achived increase of concentration of reducing sugars on a level of 52,46 g/L. Hydrolysis of sugar-beet pulp was performed in paddle stirred tank and turbine stirred tank bioreactor. Concentrations of reducing sugars were lower than previously measured through laboratory experiment in laboratory shaker on flasks (16.0 g/L or 25,00 g/L)