Lignocellulosic biomass contains cellulose, hemicellulose and lignin. we can determine the amount of cellulose using NREL procedures. But after the pretreatment (like ultrasound, ammonia, liquid hot water), we need to quantify the amount of cellulose present. Is there any formula to find out?
You need to go for the biomass analysis of the sample before pretreatment and after pretreatment both, then only you can calculate the how much cellulose was present initially, how much sample has been recovered in the biomass after pretreatment and how much cellulose has been hydrolysed. We normally follow the NREL process for the estimation of the same. Alternatively you can also estimate the glucose formation in the hydrolysate to measure cellulose hydrolysed due to pretreatment. There is no other formula to calculate the same.
Your question is at the heart of cellulose-to-glucose conversion strategies. I will approach the mensuration of remaining cellulose in a logical and simple manner. First of all, you must know the mass of cellulose in the biomass on a dry basis from your NREL procedure. Let's assume it is 100g. Of that total amount, an amount "G" is hydrolyzed of a specific mass corresponding to glucan residues (e.g., cellobiose and other oligoglucosides). You don't know this amount, but you can find it out by measuring the available glucose in the hydrolysate using an ion-exchange (IC) chromatograph. You will first need to convert all oligosaccharides to saccharides using known IC sugar protocols (see the attachment for a simple hydrolyzing protocol). Once you have all sugars in their saccharide form, you can follow the procedures listed in the publication for quantification of the glucose. You will be able to determine a mass of glucose if you use an appropriate internal standard of known amount (an non-overlapping sugar peak, for example, or any of the ISs listed in: http://www.inorganicventures.com/product-category/ic-standards). The tricky part is that once you have the glucose peak mass, you cannot simply assume it was all from the glucan! You have to know what the hemicelluloses are in the original biomass. If you are pretreating softwood, say, then the main glucose-containing hemicellulose is O-acetyl galactoGLUCOmannan. The glucose level here is ca. 1:3 for every mannan. Now, you must find the mannan peak and remember that for every 3 mannans, you will have 1 glucose. Okay, so let's say that from the original pretreatment liquor we are able to calculate 3g (ensuring that we calculate correctly for the dilution in going from the original liquor to the injected one) of glucose. We find that we have 300mg of mannose in there (from the IS calibration); thus, we will assume that in a 1:3 mass/molar relationship of glucose:mannose, we will therefore have 100mg of glucose belonging to the hemicellulose. We then subtract 100mg from the 3gs of glucose to obtain 2.9g of glucose in the hydrolyzate. Thus, using simple math, we will have 100g - 2.9g or 97.1g of cellulose left in the original biomass after the pretreament.
http://www.inorganicventures.com/product-category/ic-standards
The method and formula to determine cellulose content after pretreatment will remain same as the one before pretreatment. You only need to do quantification before and after pretreatment in order to determine the change in cellulose content resulted from pretreatment.
hi . you can use these formula
Component recovery in pretreated Biomass=
Component in pretreated biomass residue× biomass yield× 100 / Total glucan,xyaln,lignin in untreated biomass
Solid removal (%) = 100% × (1- Total solid after pretreatment (g)/Total solid before pretreatment (g)).
Xylan removal (%) = 1- (%Xylan in pretreated solids / % Xylan in raw biomass) × Solid yield.
Lignin removal (%) = 1- (%Lignin in pretreated solids / % Lignin in raw biomass) × Solid yield.
hope this helps.
http://biotechnologyforbiofuels.biomedcentral.com/articles/10.1186/1754-6834-7-71
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4015548/
Ramadoss Govindarajan Your paper Article Influence of dual salt on the pretreatment of sugarcane baga...
is great but I m a little bit confused in your calculation part, I have also emailed you, could you please elaborate on how did you calculate Cellulose recovery in your paper with the assumption of 10 g SCB?I found 40% cellulose native LC biomass and 57% after Organic solvent pretreatment because there is the removal of lignin and hemicellulose portion. On the basis of your assumptions 49%/40% is not giving proper results, Could you please explain for me.
Thank You!
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