Abstract | U ovom istraživanju optimiran je bioproces saharifikacije pulpe šećerne repe i usitnjene kore bukve pomoću pripremljenih uzoraka suspenzije egzocelularnih enzima gljiva Auricularia auricula-judae, Trametes versicolor, Sclerotium rolfsii i Neurospora crassa. Prije same optimizacije enzimske saharifikacije, određena je aktivnost egzocelularnih enzima lakaze, mangan peroksidaze, celobioza dehidrogenaze, pektinaze, glukanaze, galaktomananaze, ksilanaze i arabinaze iz suspenzije navedenih gljiva. Kod hidrolize promatran je utjecaj procesnih varijabli (pH, temperature i volumena suspenzije enzima) na uspješnost razgradnje pulpe šećerne repe i usitnjene kore bukve. Za optimiranje bioprocesa korištena je metoda odzivne površine (RSM), te je provedeno planiranje eksperimenta korištenjem Centralno kompozitnog plana (CCD). Rezultati istraživanja pokazali su da su kritični parametri za hidrolizu pulpe šećerene repe pH 5,2 - 5,3, temperatura 38 - 48 °C, količine suspenzije egzocelularnih enzima Trametes versicolor 92,918 - 94,287 μL mL-1 te Neurospora crassa 24,414 μL mL-1 a za usitnjenu koru bukve su pH 4,8 - 6,6 , temperatura 79 - 86 °C, količine enzima Sclerotium rolfsii 100,78 μL mL-1 te količine Auricularia auricula-judae 162,60 μL mL-1. Na proces saharifikacije pulpe šećerne repe najveći utjecaj imao je pH, dok su kod kore bukve najznačajniji temperatura, pH i njihov zajednički utjecaj. |
Abstract (english) | In this research, the bioprocess saccharification of sugar beet pulp and shredded beech bark was monitored with prepared samples of extracellular enzymes fungi Auricularia auricula-judae, Trametes versicolor, Sclerotium rolfsii i Neurospora crassa. Before the optimization of enzymatic saccharification, the activity of extracellular enzymes laccase, manganese peroxidase, cellobiose dehydrogenase, pectinase, glucanase, galactomananase, xylanase and arabinose from the suspension of fungi was determined. During hydrolysis, the influence of process variables (pH, temperature and volume of enzyme suspension) on the success of degradation of sugar beet pulp and beech bark, was observed. For optimization of the bioprocess, the Response Surface Methodology (RSM) was used and the planning of experiment with Central Composite Design (CCD) was done. The results of the experiment have shown that the critical units for the hydrolysis of sugar beet pulp are pH 5, 2 - 5,3, temperature 38 - 28°C, volume of suspension of extracellular enzymes Trametes versicolor 92,9 - 94,2 μL mL-1 and Neurospora crassa 24,4 μL mL-1 and for shredded beech bark pH 4,8 - 6,6 , temperature 79 - 86 °C, volume of suspension of extracellular enzymes Sclerotium rolfsii 100,7 μL mL-1 and Auricularia auricula-judae 162,60 μL mL-1. On the concentration of sugar after hydrolysis of sugar beet pulp, the biggest influence had pH whereas concerning beech bark the most influential was temperature, pH and theirs combined influence. |