PMC:4362734 / 11753-14852
Annnotations
{"target":"http://pubannotation.org/docs/sourcedb/PMC/sourceid/4362734","sourcedb":"PMC","sourceid":"4362734","source_url":"https://www.ncbi.nlm.nih.gov/pmc/4362734","text":"Hydrolysis of SEW using Celluclast 1.5L:Novo-188 at 10 FPU:12.5 CBU per g of substrate gave 2.10 ± 0.1 g of total glycosyl units (monomeric + oligomeric) per litre, which correspond to 26.1 ± 1.3 % w/w of polysaccharide conversion (Table 1). No mannosyl or galactosyl units were released from SEW using a mixture of commercial enzymes only. This is to be expected because the commercial enzyme preparation Celluclast 1.5L contains α-l-arabinofuranosidase, endo-xylanase and β-xylosidase suitable for degrading hardwood hemicellulose but lacks mannan-degrading enzymes, such as β-mannanase and/or β-mannosidase, which act as accessory enzymes in the hydrolysis of glucomannan and GGMs in softwood hemicellulose (Juturu and Wu 2013). When the commercial enzyme was supplemented with the crude enzyme preparation from Penicillium sp. the production of monomeric glucosyl units increased from 1.85 ± 0.1 to 2.48 ± 0.1 g/L. This corresponds to a 7.8 ± 0.4 % w/w improvement in monomeric glucosyl released. This improvement in release of glucosyl units (g/L) during saccharification is due to the synergistic action of following enzymes––cellulase available from Celluclast 1.5L and crude extract of Penicillium sp. (for details refer to supplementary information), β-glucosidase available from Novo-188 and the presence of β-mannanase and β-mannosidase in the crude extract of Penicillium sp. Furthermore, from control experiment in which only crude extract of Penicillium sp. is used for SEW hydrolysis, a small amount of monomeric glucosyl units (0.10 g/L) released because of lack of β-glucosidase activity in the crude extract. This in turn resulted in an accumulation of oligomeric glucosyl units (0.41 g/L; 5 % w/w cellulose conversion). Only in presence of crude extract of Penicillium sp., the conversion of soluble polymeric mannan to monomeric and oligomeric mannosyl units is achieved albeit the original hemicellulose content in SEW is small (0.3 % w/w) (Table 1). To corroborate this result further a comparison of crude extract of Penicillium sp. against commercial enzymes (both were taken on equal protein basis of 10 mg/mL) in hydrolysis of locust bean gum (1 % w/w) showed that using only crude extract twofold enhanced activity was obtained compared to commercial enzyme.\nTable 1 Saccharification of SEW\nMonomeric sugars g/L (% w/w conversion) Oligomeric sugars g/L (% w/w conversion)\nGlucose Mannose Galactose Glucosyl units Mannosyl units Galactosyl units\nCommercial enzyme 1.85 (23.0)a 0.00 0.00 0.25 (3.1)a 0.00 0.00\nPenicillium sp. crude extract (control) 0.10 (1.24)a 0.01 (33.3)a 0.00 0.41 (5.08)a 0.02 (66.7)a 0.01 (66.7)a\nCommercial enzyme + Penicillium sp. extract 2.48 (30.8)a 0.01 (33.3)a 0.00 0.00 0.02 (66.7)a 0.01 (66.7)a\nAll values in the table are the mean of triplicate experiments and have a standard deviation of ±5 %. The sugar composition (% w/w) of original SEW is––glucosyl units = 53.6; mannosyl units = 0.3; galactosyl units = 0.1\naThe numbers shown in the parentheses are % w/w conversion of sugars from the original SEW sample taken in 5 mL saccharification","divisions":[{"label":"label","span":{"begin":2286,"end":2293}},{"label":"caption","span":{"begin":2294,"end":2317}},{"label":"p","span":{"begin":2294,"end":2317}},{"label":"table","span":{"begin":2318,"end":2750}},{"label":"tr","span":{"begin":2318,"end":2398}},{"label":"th","span":{"begin":2318,"end":2357}},{"label":"th","span":{"begin":2358,"end":2398}},{"label":"tr","span":{"begin":2399,"end":2471}},{"label":"th","span":{"begin":2399,"end":2406}},{"label":"th","span":{"begin":2407,"end":2414}},{"label":"th","span":{"begin":2415,"end":2424}},{"label":"th","span":{"begin":2425,"end":2439}},{"label":"th","span":{"begin":2440,"end":2454}},{"label":"th","span":{"begin":2455,"end":2471}},{"label":"tr","span":{"begin":2472,"end":2534}},{"label":"td","span":{"begin":2472,"end":2489}},{"label":"td","span":{"begin":2490,"end":2502}},{"label":"td","span":{"begin":2503,"end":2507}},{"label":"td","span":{"begin":2508,"end":2512}},{"label":"td","span":{"begin":2513,"end":2524}},{"label":"td","span":{"begin":2525,"end":2529}},{"label":"td","span":{"begin":2530,"end":2534}},{"label":"tr","span":{"begin":2535,"end":2644}},{"label":"td","span":{"begin":2535,"end":2574}},{"label":"td","span":{"begin":2575,"end":2587}},{"label":"td","span":{"begin":2588,"end":2600}},{"label":"td","span":{"begin":2601,"end":2605}},{"label":"td","span":{"begin":2606,"end":2618}},{"label":"td","span":{"begin":2619,"end":2631}},{"label":"td","span":{"begin":2632,"end":2644}},{"label":"tr","span":{"begin":2645,"end":2750}},{"label":"td","span":{"begin":2645,"end":2688}},{"label":"td","span":{"begin":2689,"end":2701}},{"label":"td","span":{"begin":2702,"end":2714}},{"label":"td","span":{"begin":2715,"end":2719}},{"label":"td","span":{"begin":2720,"end":2724}},{"label":"td","span":{"begin":2725,"end":2737}},{"label":"td","span":{"begin":2738,"end":2750}},{"label":"p","span":{"begin":2751,"end":2970}}],"tracks":[]}