Identification of Small Aliphatic Aldehydes in Pretreated Lignocellulosic Feedstocks and Evaluation of Their Inhibitory Effects on Yeast
2015 (English)In: Journal of Agricultural and Food Chemistry, ISSN 0021-8561, E-ISSN 1520-5118, Vol. 63, no 44, 9747-9754 p.Article in journal (Refereed) Published
Six lignocellulosic hydrolysates produced through acid pretreatment were analyzed for the occurrence of formaldehyde, acetaldehyde, and glycolaldehyde. Acetaldehyde was found in all six (0.3-1.6 mM) and formaldehyde in four (<= 4.4 mM), whereas glycolaldehyde was not detected. To assess the relevance of these findings, fermentations with yeast and formaldehyde or acetaldehyde were performed in the concentration interval 0.5-10 mM. Formaldehyde already inhibited at 1.0 mM, whereas 5.0 mM acetaldehyde was needed to obtain a clear inhibitory effect. After 24 h of fermentation, 1.5 mM formaldehyde reduced the glucose consumption by 85%, the balanced ethanol yield by 92%, and the volumetric productivity by 91%. The results show that formaldehyde and acetaldehyde are prevalent in pretreated lignocellulose and that formaldehyde in some cases could explain a large part of the inhibitory effects on yeast by lignocellulosic hydrolysates, as three of six hydrolysates contained >= 1.9 mM formaldehyde, which was shown to be strongly inhibitory.
Place, publisher, year, edition, pages
2015. Vol. 63, no 44, 9747-9754 p.
formaldehyde, acetaldehyde, glycolaldehyde, mass spectrometry, lignocellulose, pretreatment, fermentation inhibition
Chemical Sciences Agricultural Science, Forestry and Fisheries
IdentifiersURN: urn:nbn:se:umu:diva-112245DOI: 10.1021/acs.jafc.5b04803ISI: 000364727400010PubMedID: 26528761OAI: oai:DiVA.org:umu-112245DiVA: diva2:878299