Maltotetraose

Characterisation of brewpub beer carbohydrates using high performance anion exchange chromatography coupled with pulsed amperometric detection.[Pubmed:24001825]

Food Chem. 2014 Jan 1;142:152-8.

High performance anion exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD) was optimised in order to quantify mannose, maltose, maltotriose, Maltotetraose, maltopentaose, maltohexaose and maltoheptaose content of beer. The method allows the determination of above mentioned oligosaccharides, in a single chromatographic run, without any pre-treatment. Limit of detection and limit of quantification were suitable for beer. Accuracy and repeatability were good for the entire amount considered. Once optimised HPAEC PAD for the specific matrix, the second goal of this research was to verify the possibility to discriminate beers, depending on their style. The carbohydrates content of brewpub commercial beers was very variable, ranging from 19.3 to 1469mg/L (mannose), 34.5 to 2882mg/L (maltose), 141.9 to 20731mg/L (maltotriose), 168.5 to 7650mg/L (Maltotetraose), 20.1 to 2537mg/L (maltopentaose), 22.9 to 3295mg/L (maltohexaose), 8.5 to 2492mg/L (maltoeptaose), even in the same style of beer. However, the carbohydrates content was useful, jointed with other compounds amount, to discriminate different styles of beer. As a matter of fact, principal component analysis put in evidence beer differences considering some fermentation conditions and colour.

Inhibition of PDGF-induced migration and TNF-alpha-induced ICAM-1 expression by maltotetraose from bamboo stem extract (BSE) in mouse vascular smooth muscle cells.[Pubmed:27067145]

Mol Nutr Food Res. 2016 Sep;60(9):2086-97.

SCOPE: Expression of intercellular adhesion molecule-1 (ICAM-1) on vascular smooth muscle cells (VSMCs) plays an important role in the progression of atherosclerosis. We investigated the effects of bamboo stem extract (BSE) on motility and ICAM-1 expression by using mouse MOVAS-1 cells. Active constituents of BSE exhibiting an inhibitory activity on TNF-alpha-induced ICAM1 expression were identified using HPLC. METHODS AND RESULTS: The effects of BSE on platelet-derived growth factor (PDGF)-BB-induced migration, tumor necrosis factor alpha (TNF-alpha)-induced expression of ICAM-1, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB) activation were investigated. BSE inhibited migration of MOVAS-1 cells and sprout formation by mouse aorta explants. Reverse transcription PCR analysis and promoter reporter assays revealed that BSE suppressed ICAM-1 expression by inhibiting NF-kappaB activity. In addition, BSE reduced adhesion between VSMCs and monocytes. Several oligosaccharides were identified in BSE. Among the oligosaccharides contained in BSE, Maltotetraose and stachyose were potent inhibitors of TNF-alpha-induced ICAM-1 expression. We confirmed that Maltotetraose reduced PDGF-induced sprout formation by mouse aorta explants and inhibited TNF-alpha-induced NF-kappaB activation and ICAM-1 expression in MOVAS-1 cells. CONCLUSION: The BSE constituent Maltotetraose may be beneficial in the suppression of early atherosclerosis development and could be developed as a dietary supplement for cardiovascular health.

Oligosaccharide synthesis in Fibrobacter succinogenes S85 and its modulation by the substrate.[Pubmed:15885092]

FEBS J. 2005 May;272(10):2416-27.

In this article we compared the metabolism of phosphorylated and unphosphorylated oligosaccharides (cellodextrins and maltodextrins) in Fibrobacter succinogenes S85 resting cells incubated with the following substrates: glucose; cellobiose; a mixture of glucose and cellobiose; and cellulose. Intracellular and extracellular media were analysed by (1)H-NMR and by TLC. The first important finding is that no cellodextrins were found to accumulate in the extracellular media of cells, regardless of the substrate; this contrasts to what is generally reported in the literature. The second finding of this work is that maltodextrins of degree of polymerization > 2 are synthesized regardless of the substrate, and can be used by the bacteria. Maltotriose plays a key role in this metabolism of maltodextrin. Maltodextrin-1-phosphate was detected in all the incubations, and a new metabolite, corresponding to a phosphorylated glucose derivative, was produced in the extracellular medium when cells were incubated with cellulose. The accumulation of these phosphorylated sugars increased with the degree of polymerization of the substrate.