Direct Ethanol Production from Xylan and Acorn Using the Starch-Fermenting Basidiomycete Fungus Phlebia acerina

Abstract

During our search for ethanol-producing basidiomycete fungi for a wide range of substrates, we isolated Phlebia acerina, which is a white rot basidiomycete fungus. It favorably converted starch into ethanol with approximately 70% yield. Although the yield decreased as the starch concentration increased, growth and fermentation were observed even at 200 g/L of starch. P. acerina produced ethanol from glucose, galactose, mannose, xylose, cellobiose, and maltose with 93%, 91%, 86%, 72%, 92%, and 68% yields, respectively. Additionally, P. acerina, which secreted xylanase and xylosidase, was capable of assimilating xylan and directly converting it to ethanol with a yield of 63%. Furthermore, P. acerina produced ethanol directly from acorns, which are plant fruits containing starch and tannins, with a yield of 70%. Tannin delayed mycelia growth, thus prolonging ethanol production; however, this did not particularly affect the yield. These results were similar to those of fermentation in a medium with the same amounts of starch and tannin as the target crop acorn, thus suggesting that P. acerina could successfully produce environmentally friendly ethanol from starch-containing lignocellulosic biomass, unlike previously reported ethanol-producing basidiomycete fungi.

Synthesis of dual physical self‐healing starch‐based hydrogels for repairing tissue defects

“…The contact angle against water droplets was studied by an instrument (KRUSS G10, Germany) for the prepared gels. [ 10 ]…”

“…The contact angle against water droplets was studied by an instrument (KRUSS G10, Germany) for the prepared gels. [10] 2.2.6 | Biodegradation of the hydrogels All gels were cut into parts with 2 cm diameter wafers and kept in phosphate buffered saline (PBS) buffer solution at 7.4 pH and 37 C for 80 h. Gels were dried and then weighed. Degradation profile of nanocomposite hydrogels was plotted according to time and material weight.…”

“…Yamada et al used starch for therapy. [ 10 ] In addition, it is a famous self‐healing hydrogel due to its abundant hydroxyl groups and physical bonds. However, starch gels have unsuitable mechanical characteristics and fragility, which in turn, prevent the development of unmodified starch‐based hydrogels.…”