Search results for "Fructan"
showing 10 items of 12 documents
Production of extracellular fructans by Gluconobacter nephelii P1464.
2015
UNLABELLED Bacterial extracellular fructans, known as levans, have potential applications in food, pharmaceutical and cosmetic industries and high fructan producing strains could contribute into the cost reduction and more extensive commercial usage of them. An acetic acid bacteria (AAB) isolate P1464 was obtained from the Microbial Strain Collection of Institute of Microbiology and Biotechnology, University of Latvia and identified as Gluconobacter nephelii by DNA-DNA hybridization and the formation of extracellular fructans by this strain was confirmed. Isolated extracellular fructose polymers were characterized using FT-IR spectroscopy and the structural features of fructan appeared as s…
Targeted Hybrid Nanocarriers as a System Enhancing the Skin Structure
2021
The skin is constantly exposed to external and internal factors that disturb its function. In this work, two nanosystems-levan nanoparticles and a surfactin-stabilized nanoemulsion were preserved (tested for microbial growth) and characterized (size, polydispersity, Zeta potential, and stability). The nanosystems were introduced in the model formulations-cream, tonic, and gel, and confirmed by TEM. The analysis showed that nanoemulsion has a spherical morphology and size 220–300 nm, while levan nanoparticles had irregular shapes independently of the use of matrix and with particle size (130–260 nm). Additionally, we examined the antiradical effect of levan nanoparticles and nanoemulsion in …
Development ofBifidobacterium lactis Bb 12 onβ-(2,6)-Linked Fructan-Containing Substrate
2004
β-(2,1)-linked fructan of plant origin (inulin) and the related oligosaccharides (FOS) as non-digestible carbohydrates, i.e., potent prebiotics, can stimulate the growth of various probiotic lactic acid bacteria, including a number of bifidobacteria strains. The related (3-(2,6)-linked fructans of microbial origin (levan and FOS), however, have scarcely been investigated in this respect. Therefore, the bifidogenic properties of various fructans, i.e., inulin, levan, fructooligosaccharides (FOS) and fructan syrup (FS), were tested as glucose substitutes in MRS media and were compared concerning their effect on the commercial strain Bifidobacterium lactis Bb 12. Although glucose was the prefe…
Influence of Prebiotic Fructans on Retronasal Aroma from Elderly Individuals
2021
This study investigates for the first time the role of fructans with prebiotic effects (oligofructose and inulin) on retronasal aroma among elderly individuals. The impact of oligofructose (20% w/w) on retronasal aroma release was investigated using proton transfer reaction-mass spectrometry (PTR-MS) after 73 elderly individuals consumed aqueous solutions aromatized with five aroma compounds (pentan-2-one, nonan-2-one, hexan-2,3-dione, octanal and linalool). The influence of oligofructose and inulin (10% w/w) on the perceived intensity (n = 26) of two aroma descriptors (butter and floral) was also studied together with the possibility of a dumping effect on aroma evaluation due to the sweet…
Germplasm evaluation to obtain inulin with high degree of polymerization in Mediterranean environment
2020
Long-chain length (DP) inulin-type fructans show pronounced beneficial effects to colon microbiota. In the past, cardoon roots for inulin production to fortify spaghetti gave very good results, but their harvest requires high costs. The aim of the work was to evaluate different types of inulin, extracted from cardoon roots and buds, topinambur tubers and chicory roots local populations in order to identify crops more suitable for high DP inulin production in Mediterranean environment. The inulin amount resulted in 115 (chicory), 390 (cardoon) and 550 g kg−1 of d.m. (topinambur). Both in cardoon roots and in topinambur tubers the DP was very high. With the aim to produce a functional food, s…
Levansucrases from Pseudomonas syringae pv. tomato and P. chlororaphis subsp. aurantiaca: Substrate specificity, polymerizing properties and usage of…
2011
Levansucrases of Pseudomonas syringae pv. tomato DC3000 (Lsc3) and Pseudomonas chlororaphis subsp. aurantiaca (also Pseudomonas aurantiaca) (LscA) have 73% identity of protein sequences, similar substrate specificity and kinetic properties. Both enzymes produce levan and fructooligosaccharides (FOS) of varied length from sucrose, raffinose and sugar beet molasses. A novel high-throughput chip-based nanoelectrospray mass spectrometric method was applied to screen alternative fructosyl acceptors for levansucrases. Lsc3 and LscA could both transfructosylate D-xylose, D-fucose, L- and D-arabinose, D-ribose, D-sorbitol, xylitol, xylobiose, D-mannitol, D-galacturonic acid and methyl-α-D-glucopyra…
A novel and simple method for the purification of extracellular levansucrase from Zymomonas mobilis.
2003
A new and simple method for the purification of extracellular levansucrase from Zymomonas mobilis from highly viscous fermentation broth was developed. After incubation of the fermentation broth with a fructose-polymer cleaving enzyme preparation (Fructozyme, Novozymes, DK) for 48 h, levansucrase precipitated as aggregates and was redissolved in a 3 M urea solution. By ongoing size-exclusion chromatography on Sephacryl S-300 the final levansucrase preparation was purified 100-fold and exhibited a specific activity of 25-35 U/mg(protein). The levansucrase was stable in 3 M urea solution for at least four months without inactivation. To maximize the enzyme yield the dynamic changes of extrace…
Fructooligosaccharide and levan producing activity of Zymomonas mobilis extracellular levansucrase
2002
Abstract The present work was devoted to investigations of the fructooligosaccharide (FOS) and levan forming activity of ethanol producing bacteria Zymomonas mobilis and their extracellular levansucrase. After cell separation the culture liquid was treated with ethanol to precipitate levan together with extracellular levansucrase. Levan–levansucrase sediment can be used as biocatalyst for fructooligosaccharide (FOS) production in sucrose syrup and levan sediment as soluble fibre source. The dynamics of sucrose conversion and glucose, fructose, and FOS formation by extracellular levansucrase showed that the fructose content increased only during the first 6 h, while the glucose content conti…
ULTRASOUND-ASSISTED AND ENZYME-ASSISTED EXTRACTION OF FRUCTANS AND PHENOLICS FROM PARSNIP (PASTINACA SATIVA L.)
2019
Parsnip (Pastinaca sativa L.) is a vegetable that gained attention due to its significant content of fructans, besides macronutrients and other biologically active compounds. The major compound of fructan class is inulin, an ingredient with prebiotic properties used in pharmaceutical and functional food industries. The main purpose of this study was to evaluate the extraction yield of fructans and phenolics in fresh and dried parsnip root following non-conventional techniques (ultrasound and enzyme -assisted extraction) and to compare it to that of the traditional method. Extraction was performed in water, as eco-friendly solvent. Ultrasound-assisted extraction was optimized for different e…
IR-spectroscopic studies of Zymomonas mobilis and levan precipitate
2002
Abstract The mid-infrared (mid-IR) absorption spectra of Zymomonas mobilis 113 “S” bacterial biomass grown in sucrose or glucose medium, and levan precipitate in the fingerprint region were studied. IR-qualitative and quantitative analyses were carried out. The principal component concentration changes in Z. mobilis biomass at different growth phases showed that protein concentration was higher in case of glucose-based medium, but the total carbohydrate concentration was higher if grown in sucrose-based medium. Low concentration of intracellular carbohydrates was a characteristic parameter of levan-producing Z. mobilis cells. It was shown that during 2-month storage of Z. mobilis inoculum i…