Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Appl Biochem Biotechnol. 2010 May;161(1-8):448-54. doi: 10.1007/s12010-009-8894-3. Epub 2010 Feb 20.
Although a number of filamentous fungi, such as Trichoderma and Aspergillus, are well known as producers of cellulases, xylanases, and accessory cellulolytic enzymes, the search for new strains and new enzymes has become a priority with the increase in diversity of biomass sources. Moreover, according to the type of pretreatment applied, biomass of the same type may require different enzyme blends to be efficiently hydrolyzed. This study evaluated cellulases, xylanases, and beta-glucosidases produced by two fungi, the thermotolerant Acrophialophora nainiana and Ceratocystis paradoxa. Cells were grown in submerged culture on three carbon sources: lactose, wheat bran, or steam-pretreated sugarcane bagasse, a commonly used cattle feed in Brazil. Xylanase and endo-1-4-beta-glucanase (CMCase) highest production were found in A. nainiana growing on lactose and reached levels of 2,200 and 2,016 IU/L, respectively. C. paradoxa showed highest activity for xylanase when grown on wheat bran and for beta-glucosidase when grown on steam-treated bagasse, at levels of 12,728 and 1,068 IU/mL, respectively.
虽然许多丝状真菌，如木霉属和曲霉属，是众所周知的纤维素酶、木聚糖酶和辅助纤维素酶的生产者，但随着生物质资源多样性的增加，寻找新的菌株和新的酶已成为当务之急。此外，根据应用的预处理类型，同一类型的生物质可能需要不同的酶混合物来进行有效水解。本研究评估了两种真菌，即耐热的拟青霉和多形拟青霉产生的纤维素酶、木聚糖酶和β-葡萄糖苷酶。细胞在三种碳源：乳糖、麦麸或蒸汽预处理的甘蔗渣（巴西常用的牛饲料）上进行液体深层发酵培养。在乳糖上生长的拟青霉产生的木聚糖酶和内切-1,4-β-葡聚糖酶（CMCase）最高，分别达到 2,200 和 2,016 IU/L。在麦麸上生长的多形拟青霉木聚糖酶活性最高，在蒸汽处理的蔗渣上生长的β-葡萄糖苷酶活性最高，分别达到 12,728 和 1,068 IU/mL。
