Abstract:
Cellulose is a key component in plant cell walls, and is the most abundant biopolymer in the world. Enzymes can be used to break cellulose down into glucose, which can then be fermented to ethanol fuel. Avicel (a purified form of cellulose), corn stover, acid treated corn stover, and paper pulp were tested using a commercially available enzymes to determine the effectiveness of the enzyme and which substrate was the most efficiently converted to glucose. Results indicate that paper pulp produces the highest glucose concentration, yielding 854.4Ug total sugar per ml of reaction in the form of glucose and trace amounts of xylose. Differences could be seen between the untreated and the pretreated
stover, with pretreatment leading to more sugar production in the form of xylose. These commercial enzymes were then compared to a set of enzymes being isolated from Clostridium Thermocellum (CelFKRS) with and without a chaperonin-like ring structure attached (SC151). A new enzyme (CelA) was added into the existing mixture and a pilot experiment was done to determine ratios that would maximize glucose production. While the CelA addition showed promise, no considerable
increase in glucose production could be obtained. Comparatively, the enzymes being isolated still fell short of commercially available enzymes in glucose production. These results demonstrate the current state of the art in commercial conversion of cellulose to fermentable sugars, and set the benchmark
for the continuing investigation toward maximizing glucose yields.
