Isolation of Filamentous Fungi Exhibiting High Endoxylanase Activity in Lignocellulose Hydrolysate

Abstract

For complete degradation of hemicellulose into its monomers from lignocellulose biomass, the synergistic action of a broad range of hydrolytic enzymes is needed. Therefore, production of enzymes from their natural producer is desirable. To obtain a powerful β-1,4-endoxylanase producing fungus, 304 environmental samples were collected from various locations in Singapore, leading to 603 isolates. Among them, 71 exhibiting β-1,4-endoxylanase activity were identified belonging mainly to the genera of Aspergillus, Penicillium, and Trichoderma. Further analysis revealed Aspergillus niger DSM 26641 as a potential and stable β-1,4-endoxylanase producer, being able to grow in hydrothermal lignocellulose hydrolysate exhibiting its maximal β-1,4-endoxylanase activity at pH 4 and 60 °C. This strain is thought to be very suitable for lactic acid production in a simultaneous saccharification and fermentation at pH values below 5.

Analysis of the fungal microbiome in exhaled breath condensate of patients with asthma

“…8 -10 Several researchers investigated virus and bacteria in airways of subjects with asthma but only a few studied fungi, which is evidence of a gap in knowledge in this important field. [11][12][13][14][15][16][17] Confirming the need for further insights on fungi colonization in patients with asthma are epidemiologic studies in the United States and Europe that associated mild sensitivity, particularly to Alternaria and Cladosporium, with the development, persistence, and severity of asthma. 6,9,10 Other fungi, including Candida, Penicillium, and Curvularia species have also been involved in asthma.…”

“…14 Although fungal sensitization is common in severe asthma, clinical relevance of fungal sensitization and its relationship with airways colonization by fungi remain unclear. 12 In light of the actual interest in this lacking field, the term severe asthma associated with fungal sensitization has been coined to illustrate the high rate of fungal sensitivity in patients with severe asthma and improvement with antifungal treatment. 11 It is important to state that severe asthma is an important phenotype, characterized by a complex management, because it is frequently accompanied by difficult, and often not reached, control.…”