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Nutrition and Metabolic Factors
Published in Michael H. Stone, Timothy J. Suchomel, W. Guy Hornsby, John P. Wagle, Aaron J. Cunanan, Strength and Conditioning in Sports, 2023
Michael H. Stone, Timothy J. Suchomel, W. Guy Hornsby, John P. Wagle, Aaron J. Cunanan
Carbohydrates are chemical compounds that consist of carbon, hydrogen, and oxygen in the ratio of approximately 1:2:1, with at least three carbon atoms. There are three primary groups of carbohydrates that include: Monosaccharides. Consist of simple sugars generally composed of three to seven carbon atoms (e.g., glucose and fructose).Oligosaccharides. Carbohydrates that consist of 2–10 monosaccharides chemically bonded together (e.g., raffinose is a trisaccharide composed of galactose, glucose, and fructose).Polysaccharides. Carbohydrates that consist of >10 monosaccharide units chemically bonded together in linear or complex branching chains (e.g., glycogen and starch).
Marine-Based Carbohydrates as a Valuable Resource for Nutraceuticals and Biotechnological Application
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Rajni Kumari, V. Vivekanand, Nidhi Pareek
It is classified on the basis of molecular size and degree of polymerization into monosaccharides, disaccharides, oligosaccharides, and polysaccharides (Knudsen et al., 2013). Monosaccharides are the simplest sugar and have the chemical formula (CH2O)n, where n is the number of carbon atoms in a molecule (Vaclavik et al., 2008), that cannot be further hydrolyzed. The rest of the other saccharides are linked by glycosidic bonds and hydrolyzed into simpler units. For example, fructose, galactose, and glucose are the main source of energy preferentially utilized by the brain and red blood cells (Ferrier, 2014). Disaccharides comprise two monomer sugar units linked by glycosidic bonds. Sucrose, lactose, trehalose, and maltose belong to disaccharides. Oligosaccharides are composed of a few monosaccharide units (2 to 20 units) (Roberfroid and Slavin, 2000) which are soluble in 80% ethanol, but intestinal enzymes are unable to digest them. Fructo-oligosaccharides, galacto-oligosaccharides, and mannan-oligosaccharides are examples of oligosaccharides (Englyst et al., 2007). Polysaccharides belong to high-molecular-weight polymeric monosaccharide units, and the degree of polymerization ranges from 70,000 to 90,000, depending on the type of polysaccharide (BeMiller, 2018). They are neither sweet in taste nor utilized directly like other carbohydrates. They may be linear (starch, cellulose) or branched (amylopectin, glycogen), homopolysaccharides (cellulose, glycogen) or heteropolysaccharides (hyaluronic acid, arabinoxylans) (Slavin, 2012).
Macronutrients
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Carbohydrates are classified into four main groups: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. The monosaccharides frequently present in food are glucose, fructose and galactose (Fig. 1). The principal disaccharides are sucrose, lactose and maltose (7–10). Both mono- and disaccharides are water-soluble and popularly called sugars. They are rapidly assimilated in the digestive tract and easily broken down with immediate release of energy. Oligosaccharides include α-glucans or malto-oligosaccharides, principally occurring from the hydrolysis of starch and non-α-glucan such as raffinose and stachyose, fructo- and galacto-oligosaccharides and other oligosaccharides (6–10). Polysaccharides may be divided into starch and non-starch polysaccharides (NSPs). NSPs are the major components of the plant cell wall such as cellulose, hemicellulose and pectin, but also include plant gum, mucilage and hydrocolloids (6–12). Dietary fibers consist of intrinsic plant cell wall polysaccharides. They are classified into two groups according to their water-solubility: insoluble dietary fibers like cellulose, hemicellulose, non-starch polysaccharide, and lignin; and soluble dietary fibers such as beta-glucan, pentosan, pectin, gum and mucilage. Some carbohydrates, like inulin, do not fit neatly into this scheme because they exist in nature in multiple molecular forms. Inulin from plants may have from 2 to 200 fructose units; as such, crossing the boundary between oligosaccharides and polysaccharides (8).
Tight junctions: from molecules to gastrointestinal diseases
Published in Tissue Barriers, 2023
Aekkacha Moonwiriyakit, Nutthapoom Pathomthongtaweechai, Peter R. Steinhagen, Papasara Chantawichitwong, Wilasinee Satianrapapong, Pawin Pongkorpsakol
Many well-known types of dietary oligosaccharide, including chitosan oligosaccharide, fructooligosaccharide, and galactomannan pentasaccharide, have attracted attention in the nutrition therapy industry. Chitosan, a positively charged linear heteropolysaccharide derived from chitin, which is the second most common natural polysaccharide in the world, is extracted from the shells of shrimp, lobster, and crab.257,258 Chitosan is utilized as an enhancer of oral-based drug delivery.259 However, chitosan was also revealed to upregulate the expression of TJ proteins (e.g., CLDN1, occludin, ZO-1) and strengthen GI barrier function in a mouse model of ulcerative colitis.260 Indeed, chitooligosaccharide (COS), a degraded product of chitosan, also augmented GI barrier integrity in a mouse closed-loop model and mucus-secreting human colonic HT-29 cells.206,261 In addition, fructooligosaccharide (FOS) relieved 5-fluorouracil (5-FU)-induced GI mucosal damage and gut inflammation in BALB/c mice.262 FOS also stimulated TJ assembly in an AMPK-dependent manner in T84 and intestinal epithelial cells.263 Furthermore, pentasaccharide of mannan (MOS5) was recently reported to possess the capacity to enhance tight junction assembly in intestinal epithelial cell monolayers, via a mechanism involving AMPK activation.264
Prediction of biological development effects on drag forces of ceramic hull coating using Reynolds-averaged Navier–Stokes-based solver
Published in Biofouling, 2023
David S. Sanz, Sergio García, Alfredo Trueba, Hafizul Islam, C. Guedes Soares
The various artificial metal structures developed hitherto in marine environments are typically adversely affected by two types of fouling. The first is corrosion, which is defined by Arzaghi et al. (2020) as the degradation of a material due to chemical and electrochemical reactions with its surrounding environment; however, the actions of plants and living organisms are harmful as well. These organisms adhere and accumulate, forming biotic deposits on submerged surfaces or simply establish contact with seawater, which contains organic components such as microorganisms, plants, algae or animals. This process is associated with a self-produced polymer matrix known as a biofilm, which can include inorganic components such as salts or corrosion products (Boullosa-Falces et al. 2020, 2022). This phenomenon is known as biofouling, which generally involves complex communities whose action induces the alteration and destruction of materials. Biofouling primarily involves polysaccharides and water. The components of polysaccharides vary depending on the species, but they typically include repeating oligosaccharides such as glucose, mannose, galactose and xylose (García and Trueba 2018).
Nucleotide binding as an allosteric regulatory mechanism for Akkermansia muciniphila β-N-acetylhexosaminidase Am2136
Published in Gut Microbes, 2022
Chang-Cheng Li, Huan Yi, Yan-Mei Wang, Xin-Yue Tang, Yi-Bo Zhu, Ying-Jie Song, Ning-Lin Zhao, Qin Huang, Xing-Yu Mou, Gui-Hua Luo, Tong-Gen Liu, Gang-Long Yang, Yu-Jiao Zeng, Li-Jie Wang, Hong Tang, Gang Fan, Rui Bao
Oligosaccharide contains different sugar units, due to its wide variety of biological activities, it has potential commercial values in food, pharmaceutical and cosmetic industries.1 β-N-acetylhexosaminidase is one of the most abundant glycosidases and is specific for the hydrolysis of both β-GlcNAc and β-N-acetylgalactosamine (β-GalNAc) units from the non-reducing end of glycan chains.2 Because of the ability to degrade a wide variety of substrates, and the wide resources including bacteria, fungi and arthropods,3,4 various therapeutic and biotechnological applications have been proposed for β-N-acetylhexosaminidase, which include conversion of industrial-scale production of distinct functional carbohydrates and glycan derivatives.5