Clarince Joyce L. Doroy ChE 426N BS ChE 4

Critique on the Research Paper: “Bioconversion of lignocellulose:  

inhibitors and detoxification” 

This research paper is written by Leif J Jönsson, Björn Alriksson both from Sweden and

Nils-Olof Nilvebrant from Norway. It talks about how enzymatic hydrolysis and microbial

fermentation during the bioconversion of lignocellulose are inhibited by substances formed

during the essential acidic thermochemical pretreatment step. Lignocellulose is an abundant

and renewable resource for biofuels, chemicals and polymers. Bio-refineries using

lignocellulosic biomass will become increasingly important in the future because they are a

potential substitute for the oil refineries using un-renewable resources. Liquid biofuels include

bioalcohols and biodiesel. Alcohols are produced from microbial fermentation of sugars or

starches by biocatalysts, yeast or bacteria. Since lignocellulosic biomass is not used for food, it

is a favorable source for alcohol.

The conversion of ethanol from lignocellulose involves an acidic thermochemical

pretreatment in order to provide the monosaccharides to be used in the fermentation process.

Lignocellulose is composed mainly of three components, namely cellulos, hemicellulose, and

lignin. Cellulose and hemicellulose when hydrolyzed may produce furan aldehydes and aliphatic

acids while lignin produces phenol depending on the process conditions. These compounds are

the major contributors to inhibition. This review focuses on the ways to minimize inhibition

problems such as conditioning and detoxification of slurries and hydrolysates, engineering

microorganisms to adapt to inhibitory environment and adjusting and improving the fermentation

technology.

The title of the article is clear enough on the purpose of the study. The abstract is also

clear, specific on what the article is all about, and representative of the whole article. In the

introduction, the author has presented basically a summary of what the next parts would be and

has also highlighted the importance of conducting the study which is very good for me. All of the

discussions in the article are relevant although some parts have been overemphasized like the

chemical treatment. The author should have focused more on the specific and important steps

in minimizing inhibition. The chemical treatment part should have been condensed and the

strategies to counteract inhibition problems should have been expanded. It is a good thing that

the author used tables and illustrations in the article to further illustrate his point. References

were also properly cited therefore making it easier for the reader to confirm facts and investigate

further on the topic.