Saccharomyces cerevisiae saccharification

In this article, we report the cloning in Escherichia coli and sequencing of an Orpinomyces P-glucosidase cDNA. The enzyme was overexpressed in and secreted from the yeast Saccharomyces cerevisiae. Physiochemical properties of the secreted enzyme were determined after it was purified. Its applicability for cellulose saccharification was also assessed. 

Simultaneous saccharification and fermentation (SSF) experiments were conducted according to NREL standard protocol (LAP-008). Each SSF flask was loaded with 3% (w/w) glucan, 1% (w/v) yeast extract, 2% (w/v) peptone, 0.05 M citrate buffer (pH 4.8), the appropriate amount of cellulase enzyme to achieve 15 FPU/g of glucan, and the appropriate amount of Saccharomyces cerevisiae DSA (provided by NREL) inoculum (starting optical density of 0.5). The SSF flasks were equipped with water traps to maintain anaerobic conditions and were incubated at 37°C with gentle rotation (130 rpm) for a period of 168 h. 

Karimi, K., Emitiazi, G., and Taherzadeh, M. J. 2006. Ethanol production from dilute-acid pretreated rice straw by simultaneous saccharification and fermentation with Mucor indicus, Rhizopus oryzae, and Saccharomyces cerevisiae. Enz Microbial Technol., 40,138-144. 

Ohta, K., Hamada, S., and Nakamura, T. 1993. Production of high concentrations of ethanol from inulin by simultaneous saccharification and fermentation using Aspergillus niger and Saccharomyces cerevisiae. App. Environ. Microbiol, 59, 729-733. 

A solid-state fermentation process for the production of ethanol from apple pomace by Saccharomyces cerevisiae was described by Khosravi and Shojaosadati (2003). A moisture content of 75% (wt/wt), an initial sugar concentration of 26% (wt/wt), and a nitrogen content of 1 % (wt/wt) were the conditions used to obtain 2.5% (wt/wt) ethanol without saccharification and 8% (wt/wt) with saccharification. The results indicate that... 

Four microorganisms, delignification, saccharification with Trichoderma sp., biomass formation with Candida utilis and Saccharomyces cerevisiae A.foetidus produces citric acid 16.1 g/ 100 g DM and 3% methanol Amylases... 

Keywords Saccharomyces cerevisiae Simultaneous saccharification and fermentation ... 

Saccharomyces cerevisiae is the dominant microorganism in the first generation of fuel ethanol production. In recent years, the worldwide bioethanol production reached around 80 billion liters per year. In a typical industrial scale bioethanol fermentation process using Saccharomyces cerevisiae, around 8-14% (v/v) ethanol is produced and the glucose to bioethanol yield is usually over 90% of the theoretical yield. In some processes, simultaneous saccharification and fermentation is applied, in which a-amylase/glucoa-mylase is mixed with Saccharomyces cerevisiae and starchy raw materials. Most of yeast cells harvested in the fermentation are recycled and sent back in order to enhance the cell concentration in the fermenter. Around 5-10% yeast cells end up in Dried Distillers Grains with Solubles (DDGS), which could be sold as animal feed. 

The enzymatic activity and ethanol formation abilities of Fusarium oxysporum makes it ideal for a simultaneous saccharification and biological conversion process [82]. Birch wood containing high xylose content, was used for the simultaneous saccharification and biological conversion test [82]. The birch chips were steam-treated at 185 °C for 30 min. Cellulase from Trichoderma reesei and either Saccharomyces cerevisiae or Fusarium oxysporum were used for the simultaneous saccharification and biological conversion process. Rates of hydrolysis and bioconversion were studied by varying the amount of T. reesei cellulase, since the... 

FW Blending, saccharification Calcium-alginate containing immobilized Saccharomyces cerevisiae H058 Continuous ethanol fermentation 1870-mL Coltmm NR... 

FW Blending, saccharification Saccharomyces cerevisiae H058 Non-sterilized batch 500- mL Flasks 60... 

Bakery FW with cheese whey Liquefaction, saccharification. Saccharomyces cerevisiae Batch 14-L Microferm Benchtop Fermentor 13... 

Yan, S., Yao, J., Yao, L., Zhi, Z., Chen, X., Wu, J., 2012a. Fed batch enzymatic saccharification of food waste improves the sugar concentration in the hydrolysates and eventually the ethanol fermentation by Saccharomyces cerevisiae H058. Brazilian Archives of Biology and Technology 55 (2), 183—192. 

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