We have previously demonstrated the production of glucooligosaccharides via a fermentation of sucrose with Leuconostoc mesenteroides NRRL B-742 using sodium hydroxide (NaOH) to control the pH. Because NaOH is expensive, we sought to minimize the cost of our process by substituting hydrated lime and saccharate of lime (lime sucrate) in its place. The yield of glucooligosaccharides using either 5 % lime (41.
View Article and Find Full Text PDFIn this study, sugarcane bagasse was pretreated with ammonium hydroxide, and the effectiveness of the pretreatment on enzyme hydrolysis and ethanol production was examined. Bagasse was soaked in ammonium hydroxide and water at a ratio of 1:0.5:8 for 0-4 days at 70 °C.
View Article and Find Full Text PDFA series of oligosaccharides (cellobio-oligosaccharides) ranging from degrees of polymer 3 to 6 were synthesized by Leuconostoc mesenteroides B-512 FMCM in the presence of cellobiose. The major oligosaccharides were the trisaccharides, α-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 4)-D-glucopyranose and α-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl-(1 → 4)-D-glucopyranose. These cellobio-oligosaccharides were inhibitory on mutansucrase, an enzyme that causes dental caries.
View Article and Find Full Text PDFJ Ind Microbiol Biotechnol
July 2011
A challenge facing the biofuel industry is to develop an economically viable and sustainable biorefinery. The existing potential biorefineries in Louisiana, raw sugar mills, operate only 3 months of the year. For year-round operation, they must adopt other feedstocks, besides sugar cane, as supplemental feedstocks.
View Article and Find Full Text PDFThe economics driving biorefinery development requires high value-added products such as cellobiose for financial feasibility. This research describes a simple technology for increasing cellobiose yields during lignocellulosic hydrolysis. The yield of cellobiose produced during cellulose hydrolysis was maximized by modification of reaction conditions.
View Article and Find Full Text PDFAppl Biochem Biotechnol
May 2010
Sugarcane bagasse is the major by-product of the sugar industry. It has a great potential for the production of biofuels and chemicals due to its considerable amount of cellulose and hemicellulose. In this study, we investigated a simple and economic pretreatment process using dilute ammonia for the storage of sugarcane bagasse.
View Article and Find Full Text PDFBioresour Technol
January 2009
Reactive oxygen species (ROS) such as singlet oxygen ((1)O(2)), superoxide (O(2)(-)), hydroxyl radicals (OH(*)), or hypochlorite ion (OCl(-)), can remove both hemicellulose and lignin from lignocellulose. Ox-B (US Patent 6,866,870), an ROS producing solution containing sodium hypochlorite and hydrogen peroxide, was investigated for its ability to oxidize sugarcane bagasse. Treatment with equivalent amounts of hypochlorite produced similar results.
View Article and Find Full Text PDFAppl Biochem Biotechnol
March 2008
Sugar cane bagasse consists of hemicellulose (24%) and cellulose (38%), and bioconversion of both fractions to ethanol should be considered for a viable process. We have evaluated the hydrolysis of pretreated bagasse with combinations of cellulase, beta-glucosidase, and hemicellulase. Ground bagasse was pretreated either by the AFEX process (2NH(3): 1 biomass, 100 degrees C, 30 min) or with NH(4)OH (0.
View Article and Find Full Text PDFAppl Biochem Biotechnol
March 2008
There is a growing market for oligosaccharides as sweeteners, prebiotics, anticariogenic compounds, and immunostimulating agents in both food and pharmaceutical industries. Interest in novel carbohydrate-based products has grown because of their reduced toxicity and low immune response. Cellobiose is potentially valuable as a nondigestible sugar.
View Article and Find Full Text PDFIn this study, three epigallocatechin gallate glycosides were synthesized by the acceptor reaction of a glucansucrase produced by Leuconostoc mesenteroides B-1299CB with epigallocatechin gallate (EGCG) and sucrose. Each of these glycosides was then purified, and the structures were assigned as follows: epigallocatechin gallate 7-O-alpha-D-glucopyranoside (EGCG-G1); epigallocatechin gallate 4'-O-alpha-D-glucopyranoside (EGCG-G1'); and epigallocatechin gallate 7,4'-O-alpha-D-glucopyranoside (EGCG-G2). One of these compounds (EGCG-G1) was a novel compound.
View Article and Find Full Text PDFLeuconostoc mesenteroides B-512 FMC produces dextran and levan using sucrose. Because of the industrial importance of dextrans and oligosaccharides synthesized by dextransucrase (one of glycansucrases from L. mesenteroides), much is known about the dextransucrase, including expression and regulation of gene.
View Article and Find Full Text PDFMetabolic acids produced by oral pathogens demineralize tooth surfaces, leading to dental caries. Glucosyltransferases are the key factor in this process. We synthesized various modified oligosaccharides and tested them for their inhibitory effects on glucosyltransferase activity.
View Article and Find Full Text PDFThe Lipomyces starkeyi alpha-amylase (LSA) gene encoding soluble starch-degrading alpha-amylase was cloned and characterized from a derepressed and partially constitutive mutant for both dextranase and amylase activities. The nucleotide (nt) sequence of the cDNA fragment reveals an open reading frame of 1944 bp encoding a 619 amino acid (aa) mature protein (LSA) with a calculated molecular weight of 68.709 kDa that was estimated to be about 73 kDa, including His tag (4 kDa) based on SDS-PAGE (10% acrylamide gel), activity staining, and the Western blotting, using anti-amylase-Ab.
View Article and Find Full Text PDFLipomyces starkeyi ATCC 20825 is a derepressed mutant derived from L. starkeyi ATCC 12659. It requires the presence of an inducer before it produces dextranase.
View Article and Find Full Text PDF