Mixture Of Fructo-oligosaccharides Research Articles

Study of the production of fructose and ethanol from sucrose media by Saccharomyces cerevisiae.

The production of ethanol and enriched fructose syrups from a synthetic medium with various sucrose concentrations using the mutant Saccharomyces cerevisiae ATCC 36858 was investigated. In batch tests, fructose yields were above 90% of theoretical values for the sucrose concentrations between 35 g/l and 257 g/l. The specific growth rates and biomass yields were from 0.218 to 0.128 h(-1) and from 0.160 to 0.075 g biomass/g of glucose and fructose consumed, respectively. Ethanol yields were in the range of 72 to 85% of theoretical value when sucrose concentrations were above 81 g/l. The volumetric ethanol productivity was 2.23 g ethanol/(l h) in a medium containing 216 g/l sucrose. Fructo-oligosaccharides and glycerol were also produced in the process. A maximum fructo-oligosaccharides concentration (up to 9 g/l) was attained in the 257 g/l sucrose medium in the first 7 h of the fermentation. These sugars started to be consumed when the concentrations of sucrose in the media were less than 30% of its initial values. The fructo-oligosaccharides mixture was composed of 6-kestose (61.5%), neokestose (29.7%) and 1-kestose (8.8%). The concentration of glycerol produced in the process was less than 9 g/l. These results will be useful in the production of enriched fructose syrups and ethanol using sucrose-based raw materials.

Structure of fructans from excised leaves of New Zealand flax

The accumulation of total water-soluble carbohydrate, and specifically sucrose and fructan, by excised leaves of Phormium tenax and P. cookianum (family Phormiaceae J. G. Agardh, order Asparagales) was investigated. Total water-soluble carbohydrate content of excised leaves of P. tenax and P. cookianum increased during 48 h of continuous illumination at an average rate of 1.3 and 0.9 mg g −1 fresh weight leaf per hour, respectively. The sucrose content of excised leaves increased throughout the experimental period. The fructan content of excised leaves of P. tenax increased slightly throughout the experimental period, whilst that of P. cookianum was variable and showed no overall change. Chemical and spectroscopic analysis of the fructans obtained from the two Phormium species showed that they were similar to each other and contained mostly 1-linked and terminal fructofuranosyl (Fru f) residues, together with smaller amounts of 6-linked Fru f, 1,6-branched Fru f, terminal and 6-linked glucopyranosyl residues. Separation of the fructans by thin-layer and high-performance anion-exchange chromatography revealed the presence of a complex mixture of fructo-oligosaccharides and higher molecular weight fructan. The branched structure of the fructans isolated from excised leaves of Phormium resembles that of fructans and fructo-oligosaccharides isolated from some related species within the order Asparagales ( Agave vera cruz, Cordyline australis and Urginea maritima), but is distinct from the linear structure of fructans from others ( Allium cepa and Asparagus officinalis). The structural heterogeniety of fructans within both the order Asparagales and superorder Liliiflorae may be a useful chemotaxonomic aid.

Metabolism of chicory fructooligosaccharides by bifidobacteria

Two types of chicory fructooligosaccharides (Fibruline Instant and Fibrulose F97) were metabolised by Bifidobacterium longum, B. infantis and B. angulatum. Chromatographic analysis of the medium after 120 h revealed a consumption of all the fructose oligomers present in the commercial chicory fructooligosaccharide mixtures for all the strains. Maximum measurable degree of polymerisation of the substrates before fermentation was 41. The higher biomass production was reached with B. infantis (1.4 and 1.7 g dry wt l−1) for its cultivation on medium complemented, respectively, with Fibruline Instant and Fibrulose F97 as substrate. These results give the opportunity to use chicory fructooligosaccharides as a prebiotic.

A forced-flow membrane reactor for transfructosylation using ceramic membrane.

A forced-flow membrane reactor system for transfructosylation was investigated using several ceramic membranes having different pore sizes. beta-Fructofuranosidase from Aspergillus niger ATCC 20611 was immobilized chemically to the inner surface of a ceramic membrane activated by a silane-coupling reagent. Sucrose solution was forced through the ceramic membrane by crossflow filtration while transfructosylation took place. The saccharide composition of the product, which was a mixture of fructooligosaccharides (FOS), was a function of the permeate flux, which was easily controlled by pressure. Using 0.2 micrometer pore size of symmetric ceramic membrane, the volumetric productivity obtained was 3.87 kg m(-3) s(-1), which was 560 times higher than that in a reported batch system, with a short residence time of 11 s. The half-life of the immobilized enzyme in the membrane was estimated to be 35 days by a long-term operation.

Separation of a fructo-oligosaccharide mixture by hydrophilic interaction chromatography using silica-based micropellicular sorbents

An amino-bonded, micropellicular stationary phase was prepared and applied to the separation of a fructo-oligosaccharide mixture. Glucose, sucrose, 1-kestose, nystose and fructose-nystose were eluted in sequence on a 10-cm long column. A linear response was obtained by plotting the peak area vs. the sample loading of each carbohydrate. The logarithm difference of capacity factors (Δlog k′) were estimated from the slopes of the plots of the capacity factor vs. the number of fructosyl residues in the carbohydrates to be 0.58 and 0.47, respectively, for the columns packed with micropellicular and totally porous sorbents. The use of fluid-impervious, micropellicular sorbents led to a higher value of Δlog k′, compared with totally porous sorbents. This finding could explain why the pellicular stationary phase is effective for the separation of macromolecules like proteins. To reduce the effect of the extra-column dead volume on the chromatographic efficiency, the extra-column tube should be as short as possible, especially for the column packed with micropellicular sorbents.

Continuous Separation of Fructooligosaccharides Using an Annular Chromatograph

Abstract A continuous rotating annular chromatograph with a rotating feed nozzle and product collectors was used to separate mixtures of fructooligosaccharides. Oligosaccharides could be continuously separated from monosaccharides and a disaccharide to obtain a lower calorie sweetener. Analytical solutions agreed well with experimental results.

The Production of β-Fructofuranosidase fromBifidobacteriumspp.

The productions of β-fructofuranosidase from Bifidohacterium longum A1, B. adolescentis G1, and four other strains of Bifidobacteria were investigated. All strains used in this study were grown in modified BL broth containing a mixture of fructooligosaccharides [1F (1-β-D-fructofuranosyl)n-1sucrose, GFn (n = 2 – 5)] as the only carbon source. Hydrolyses of 1-kestose, sucrose, and inulin were detected in the extract of the cell. The highest activity on 1-kestose was detected in the extract of B. longum A1 followed by B. adolescentis G1. The other extracts weakly attacked 1-kestose. The relative activities of the extract of B. adolescentis G1 for 1-kestose, nystose, 1F-fructosylnystose, sucrose, and inulin were 100, 82.5, 50.8, 28.3, and 15.0, respectively. The relative activities for various substrates differed from invertases (yeast β-fructofuranosidases) and exo-inulinase from Penicillium trzehinskii.

Purification and Properties of a Fructooligosaccharide-producing β-Fructofuranosidase fromAspergillus nigerATCC 20611

A fructooligosaccharide-producing β-fruetofuranosidase was purified from cells of Aspergillus niger ATCC 20611. The molecular weight was 340,000 by gel filtration. The optimum pH of the enzyme was 5.0 ~ 6.0 and the optimum temperature was 50~60°C. The enzyme was rendered inactive by 1 mM Hg2+ and the Km value for sucrose was 0.29 m. The enzyme catalyzed an almost exclusively fructosyl transfer reaction in a 50% sucrose solution to produce a mixture of fructooligosaccharides and glucose, but both fructosyl transfer and hydrolytic action were observed in a 0.5 % solution. The β-fructofuranosidase showed a high regiospecificity to transfer the fructosyl moiety for the 1-OH group of terminal fructofuranosides.

Purification and properties of a fructooligosaccharide-producing .BETA.-fructofuranosidase from Aspergillus niger ATCC 20611.

A fructooligosaccharide-producing β-fructoturanosidase was purified from cells of Aspergillus niger ATCC 20611. The molecular weight was 340, 000 by gel filtration. The optimum pH of the enzyme was 5.0-6.0 and the optimum temperature was 50-60°C. The enzyme was rendered inactive by 1 HIM Hg2+ and the Km value for sucrose was 0.29 M. The enzyme catalyzed an almost exclusively fructosyl transfer reaction in a 50% sucrose solution to produce a mixture of fructooligosaccharides and glucose, but both fructosyl transfer and hydrolytic action were observed in a 0.5 % solution. The β-fructofuranosidase showed a high regiospecificity to transfer the fructosyl moiety for the 1-OH group of terminal fructofuranosides.

Toxicological Evaluation of Neosugar: Genotoxicity, Carcinogenicity, and Chronic Toxicity

Neosugar, a fructooligosaccharide mixture, was tested for genotoxicity in three assays: (1) microbial reverse mutation assays in Salmonella typhimurium (Ames assay) and Escherichia coli WP2 uvr A, (2) the L5178Y mouse lymphoma TK± mammalian cell mutation assay, and (3) an assay for the induction of unscheduled DNA synthesis (UDS) in human epithelioid cells (HeLa S3). Each assay was conducted at a wide range of dose levels, both with and without metabolic activation. Test results gave no indication that neosugar possessed any genotoxic potential. The carcinogenicity and chronic toxicity of neosugar were examined in Fischer 344 rats. Rats were fed diets containing 0, 8000, 20,000, or 50,000 ppm neosugar for 104 weeks. No dose-related effects on survival, growth, hematology, blood chemistry, organ weights, or nonneoplastic lesions were observed. The incidence of rare and spontaneous tumors was comparable between control and neosugar treatment groups, with the exception of pituitary adenomas in male rats. In light of the background incidence of this tumor and an equivocal dose-response trend, it is unlikely that neosugar treatment is related to the incidence of pituitary adenomas in male rats. The results of this study indicate that neosugar is nonmutagenic and that rats are not adversely affected by chronic neosugar exposure.

A Fructooligosaccharide-producing Enzyme fromAspergillus nigerATCC 20611

The fructosyl transfer to sucrose was investigated, and Aspergillus niger ATCC 20611 was selected as the most suitable strain for fructooligosaccharide production. This strain showed very high enzyme productivity, and its transfructosylating activity was very strong compared to its hydrolyzing activity. Fructooligosaccharides could be more effectively prepared with a higher concentration of sucrose if use could be made of an enzyme having higher transfructosylating ability. Treatment of 50% (w/v) sucrose with the A. niger enzyme afforded a mixture of fructooligosaccharides with inulin-type structures of 1F(1-β-fructofuranosyl)n-sucrose (n = 1 to 3). The individual saccharides could be separated by the combination of a carbon column chromatography and preparative HPLC.

A fructooligosaccharide-producing enzyme from Aspergillus niger ATCC 20611.

The fructosyl transfer to sucrose was investigated, and Aspergillus niger ATCC 20611 was selected as the most suitable strain for fructooligosaccharide production. This strain showed very high enzyme productivity, and its transfructosylating activity was very strong compared to its hydrolyzing activity. Fructooligosaccharides could be more effectively prepared with a higher concentration of sucrose if use could be made of an enzyme having higher transfructosylating ability. Treatment of 50% (w/v) sucrose with the A. niger enzyme afforded a mixture of fructooligosaccharides with inulin-type structures of 1F(1-β-fructofuranosyl)n-sucrose (n = 1 to 3). The individual saccharides could be separated by the combination of a carbon column chromatography and preparative HPLC.

Quantative Analyses of Fructooligosaccharides by Gas Liquid Chromatography and High Performance Liquid Chromatography

The analysis by gas liquid chromatography (GLC) and high performance liquid chromatography (HPLC) of fructooligosaccharides (GF2, GF3, GF4) in foods, such as candy and cookies containing “Neosugar”, was investigated. Fructooligosaccharides in a mixture of monosaccharides, disaccharides and fructooligosaccharides could be analyzed by GLC and HPLC with equal accuracy.In the case of a mixture of fructooligosaccharides and glycosyloligosaccharides (GnF), good separation of GF2 and G2F and of GF3 and G3F were obtained by GLC, but on HPLC, the separation of GF3 and G3F was not satisfactory. Thus, with mixtures of fructooligosaccharides and glycosyloligosaccharides, GLC is preferable for fructooligosaccharides analysis.