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Medium Design for Cell Culture Processing
Published in Wei-Shou Hu, Cell Culture Bioprocess Engineering, 2020
Other sugars, especially galactose, mannose, and fructose, may also be used as alternative sugars. All cultured cells express the GLUT1 transporter at a significant level, and take up glucose readily under a normal glucose level in medium. Galactose is also transported by GLUT1, and can thus be used as an alternative sugar to glucose. The KM for galactose uptake is higher than for glucose. In the concentration range commonly used for glucose, galactose is taken up by cells at a lower rate, resulting in lower lactic acid production in the culture. Fructose is transported by the GLUT5 transporter. The KM for fructose transport by GLUT5 is also high. Thus, similar to galactose, the uptake rate for fructose is lower than for glucose unless a high concentration of fructose is used. However, not all cells can utilize fructose as some do not express GLUT5.
Potential Feedstocks for Second-Generation Ethanol Production in Brazil
Published in Arindam Kuila, Sustainable Biofuel and Biomass, 2019
Luiza Helena Da Silva Martins, João Moreira Neto, Paulo Weslem Portal Gomes, Johnatt Allan Rocha De Oliveira, Eduardo Dellosso Penteado, Andrea Komesu
At present, several technologies are in use for converting cellulosic feedstocks into ethanol. However, all these technologies can be grouped into two broad categories, namely, hydrolysis and thermochemical conversion. In hydrolysis, the polysaccharides (cellulose and hemicellulose) present in a feedstock are broken down to free sugar molecules (glucose, mannose, galactose, xylose, and arabinose). These free sugar molecules are then fermented to produce ethanol. As lignin cannot be used for ethanol production, it is removed during the conversion process and is generally utilized to meet electricity or heat requirement of an ethanol mill. In the thermochemical conversion process, the feedstock is gasified to produce syngas (a mixture of carbon monoxide, hydrogen, CO2, methane, and nitrogen) and then syngas is either fermented or catalytically converted to obtain ethanol (Dwivedi et al., 2009). Details of specific technologies under each broad category of conversion technology, i.e., hydrolysis and thermochemical conversion are discussed by Dwivedi et al. (2009). Lignocellulosic biomass ethanol production demands a good knowledge of the material structure used in the biotechnological transformation (Oliveira et al., 2016).
Glycan-Based Nanocarriers in Drug Delivery
Published in Raj K. Keservani, Anil K. Sharma, Rajesh K. Kesharwani, Drug Delivery Approaches and Nanosystems, 2017
Songul Yasar Yildiz, Merve Erginer, Tuba Demirci, Juergen Hemberger, Ebru Toksoy Oner
Glycans are not only used for functionalization of the nanocarriers but also used for construction of those nano-sized devices/materials for biomedical applications since glycans play numerous roles in organisms from immunogenity to cell recognition, communications and so on. Many glycans play a role in different parts of the homeostatic mechanism. For instance sialic acid, mainly bound to glycoproteins is essential for the communication and recognition with the immune system. It is known that erythrocytes without sialic acid on the surface are removed rapidly from the blood by the immune system. Another monosaccharide, mannose, plays a crucial role in protein glycosylation. Mannose binding C-type lectin proteins are important for cell surface recognition and communication. Studies with mannose generally focus on cell surface targeting. Galactose is essential for cell targeting or blood type detection due to antigen structure. Hyaluronic acid is a common glycan for vertebrate tissues but is mostly found in connective tissues and body fluids with many functions like lubrication, plasma protein regulation, filtration, homeostasis of the water. Furthermore rhamnose which is generally found in bacteria and higher organisms such as plants plays important roles in cell survival.
Glycolipids from natural sources: dry liquid crystal properties, hydrogen bonding and molecular mobility of Palm Kernel oil mannosides
Published in Liquid Crystals, 2020
Alfonso Martinez-Felipe, Thamil Selvi Velayutham, Nurul Fadhilah Kamalul Aripin, Marina Yusoff, Emma Farquharson, Rauzah Hashim
Previous studies of glycoside surfactant systems employed common mono-/disaccharide such as glucose, galactose and maltose [16–25]. As part of a systematic study to develop new glycosides, we are now employing mannose, another naturally abundant sugar with many known therapeutic properties such as treatment of urinary tract infections [26,27]. Mannose is also an epimer of glucose at C2 position and etymologically it is also derived from the word manna, which is commonly used as an energy source inspired by the biblical stories [28]. Therefore, we have synthesised a new natural product-based glycoside, bearing a mannose polar sugar head and using palm kernel oil as the lipid hydrophobic component, αManPKO. Thus, αManPKO is a mixture whose alkyl chains are those components of PKO, the major ones are shown in Figure 1.
Synergistic effect of Fusarium lateritium LP7 and Trichoderma viride LP5 promotes ethoxylated oleyl-cetyl alcohol biodegradation
Published in Journal of Environmental Science and Health, Part A, 2020
The ability of tested pure cultures and consortium to produce different carbohydrates is in line with the results of other authors which revealed production of different carbohydrates by filamentous fungi and establish a link between their production, the types of fungal strain and experimental conditions.[22] The current study indicates that addition EOCA in growth medium of could be used as inducer for production of some specific carbohydrates such as xylose, mannose, maltose and lactone. Maltose is used in the manufacture of dietetic and sports food stuffs, bread, wine, preserves and beverages. Furthermore, maltose is utilized in microbiology and pharmacology.[23,24] As a diabetic sweetener, D-xylose can be used in a wide variety of industries including: food production, beverage, pharmaceutical, cosmetics, and various other industries.[25] Carbohydrate lactones have found broad application as building blocks for the synthesis of important bioactive compounds and natural products.[26] D-mannose has been widely used in the food, pharmaceutical and poultry industries, acting as a source of dietary supplements, starting material for the synthesis of drugs and blocking colonization in animal feeds.[27]
AIM and NBO analyses on hydrogen bonds formation in sugar-based surfactants (α/β-d -mannose and n-octyl-α/β-d -mannopyranoside): a density functional theory study
Published in Liquid Crystals, 2014
Zahrabatoul Mosapour Kotena, Reza Behjatmanesh–Ardakani, Rauzah Hashim
Like glucose, mannose is classified as a simple sugar from the aldohexose series of the carbohydrate family.[1] Mannose are generally found in a number of fruits (including cranberries),[2] and dextro mannose (d-mannose) is thought to keep bacteria from remaining on the walls of the urinary tract, which is why it is used to prevent and treat urinary tract infections.[3] Mannose and glucose are different from each other since they are epimers at the C2 position but, surprisingly, many of their physical behaviours are different.[4] In addition, there are two possible stereoisomers at the C1 position, two possible orientations (axial/equatorial) of the hydroxyl group, thus resulting in two anomers, namely, α-d-mannose and β-d-mannose. Mannose is chiral in the ring form, but achiral in the linear form. Physically, α-d-mannose is a sweet-tasting sugar, while β-d-mannose, on the other hand, tastes bitter. A pure solution of α-d-mannose, however, loses its sweetness over time. When monosaccharides are dissolved in water, they undergo reversible ring-opening reactions, so the ring forms exist in equilibrium with the linear forms. The C1 is then free to rotate (mutarotation), and β-d-mannose can then form when it changes back into the ring form. When equilibrium is reached, there is more of the β-isomer than the α-isomer, because in the β-isomer, the hydroxyl on the C1 is in a more stable (equatorial) position.[5] The physical and chemical properties of these monosaccharides depend upon the molecular shape and the extent of hydrogen bonding interactions. By attaching a lipid to sugar moiety, it results in a glycolipid molecule, whose solubility and other physical properties are substantially changed. A glycolipid molecule possesses a water-loving polar head group linked to a water-hating hydrophobic alkyl tail. This dichotomy within the glycolipid molecule is an enabling feature, which drives the molecules to form many interesting self-assembly structures, hence resulting in liquid-crystalline properties, both via thermal and solvent effects. The ability of these materials to form a diverse range of self-assembly structures thermotropically as well as lyotropically paves the way to many potential applications in nano-and biotechnology.[6,7] Compared to many conventional ionic surfactants, glycolipids are biodegradable, non-toxic and may be derived from many common and cheap natural resources.[8] Glycolipids are commonly found in nature, especially in cell membranes, and are known to be involved in cellular functions,[9] suggesting that they are particularly attractive as a new type of lipids for targeted liposomal drug delivery systems.[10,11]