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Biomolecules from Microalgae for Commercial Applications
Published in Kalyan Gayen, Tridib Kumar Bhowmick, Sunil K. Maity, Sustainable Downstream Processing of Microalgae for Industrial Application, 2019
Meghna Rajvanshi, Uma Shankar Sagaram, G. Venkata Subhash, G. Raja Krishna Kumar, Chitranshu Kumar, Sridharan Govindachary, Santanu Dasgupta
A notable microalgal polysaccharide molecule that gained significant market share is β-glucan. It is a cell wall component formed through the linking of D-glucose units through β-glycosidic bonds (Zhu, Du, and Xu 2016). It gained a lot of attention because of its well-proven bioactive properties such as anti-tumor, anti-obesity, anti-inflammatory, anti-osteoporotic, anti-allergic and immunomodulating activities (Bashir and Choi 2017). Crops like barley and oats are rich sources of β-glucan, containing ~20 and 8%, respectively. However, microalgal species like Euglena gracialis, Chlorella pyrenoidosa and Nannochloropsis also are potent sources of β-glucan. Nannochloropsis has been reported to contain 3% to 6% β-glucan. Reported structures of β-glucan in microalgae are β-1,3 glucan, β-1,3/1,6 glucan and β-1,6/1,3 glucan. β-glucan in Isochrysis galbana and Chlorella pyrenoidosa is branched, whereas it is linear (β-1,3 glucan) in Euglena gracilis and called paramylon (Rojo et al. 2017). E. gracilis has been used by Kemin Industries to produce β-glucan commercially for human and animal nutrition, and products are sold under the brand name BitaVia Pure and BitaVia Complete for human nutrition and Aleta for animal nutrition.
Valorization of Hemicelluloses
Published in Jean-Luc Wertz, Magali Deleu, Séverine Coppée, Aurore Richel, Hemicelluloses and Lignin in Biorefineries, 2017
Jean-Luc Wertz, Magali Deleu, Séverine Coppée, Aurore Richel
Seed storage hemicelluloses are used directly as products in the food industry, for example, guar and locust bean gums (galactomannans), konjac gum (glucomannans), and tamarind gum (XyGs).3 Furthermore, the hemicelluloses give important properties to many food and feed products. In the baking industry, the arabinoxylans affect baking quality. Mixed-linkage glucans and arabinoxylans are well-known antinutritional compounds in animal feed, and they can cause filtering and haze problems in the brewery industry due to their viscosity. To correct these problems, hemicellulases are added to feed and are used in the baking and brewery industries. Mixed-linkage glucans have a documented cholesterol-lowering effect in hypercholesterolemic humans and daily intake of mixed-linkage glucans is recommended by the U.S. Food and Drug Administration. Furthermore, xylooligosaccharides (XOS) and arabinoxylooligosaccharides (AXOS) have prebiotic properties.9–11
Novel Microbial Compounds as a Boon in Health Management
Published in Jyoti Ranjan Rout, Rout George Kerry, Abinash Dutta, Biotechnological Advances for Microbiology, Molecular Biology, and Nanotechnology, 2022
Shubha Rani Sharma, Rajani Sharma, Debasish Kar
Fungal cell wall mainly contains glucan, chitin, and mannoproteins. Glucan is the polymer of glucose. The monomer units of glucose are linked by (1–3)-β or (1,6)-β bonds. Echinocandins inhibit noncompetitively β-1,3-glucan synthase and disrupt the cell wall formation in fungus (Emri et al., 2013). Pneumocandins that belong to the echinocandins family also show a similar mechanism of inhibitory action on the growth of fungus (Chen et al., 2015). Chitin is also a polysaccharide made of β-(1,4)-linked N-acetylglucosamine monomers. Secondary metabolites belonging to a peptide-nucleoside family, which are similar to UDP-N-acetylglucosamine, inhibit competitively chitin synthesis. Few of the antifungal compounds have been noted in Table 5.9.
Industrial production and applications of α/β linear and branched glucans
Published in Indian Chemical Engineer, 2021
Geetha Venkatachalam, Senthilkumar Arumugam, Mukesh Doble
α-glucans are glucose monomers linked by α-glucosidic bonds. The structure of α-glucans varies on different microbial strain. Dextran (Figure 1A) is produced by Lactobacillus hilgardii, Leuconostoc, mesenteroides, Leuconostoc dextranicum and Streptococcus. Amylopectin (Figure 1B) are highly branched glucans (main component 70–85% in common starches) which are found in higher plants (corn, rice and sorghum) and animals. Glycogen (Figure 1C) are highly branched α-glucans (contains 60,000 glucose residues) which are major carbohydrate forms (liver 6–8% wet weight), and are found in animals and higher plants (starch analog) [5]. Pullulan (Figure 1D), the water-soluble gum-like glucans are produced by strains of Aureobasidium pullulans [4,6,7]. Pea starch (Figure 1E) are highly branched glucans with rich amylose content and are derived from plant sources. An overview of some of the important α glucans, their manufacturers and applications are listed in Table 1 [8–12].
Anticancer effects of carboxymethylated (1→3)(1→6)-β-D-glucan (botryosphaeran) on multicellular tumor spheroids of MCF-7 cells as a model of breast cancer
Published in Journal of Toxicology and Environmental Health, Part A, 2022
Andressa Y. Fujiike, Celina Y. A. L. Lee, Fabiana S. T. Rodrigues, Larissa C. B. Oliveira, Aneli M. Barbosa-Dekker, Robert F. H. Dekker, Ilce M. S. Cólus, Juliana M. Serpeloni
Carbohydrate biopolymers such as the β-glucans belong to a class of biomacromolecules described as modifiers of the biological response capable of beneficially modulating the immune system (Bohn and BeMiller 1995; Silva et al. 2017). The mechanism of action of β-glucans is mediated upon binding to host cell receptors, which subsequently activate internal signaling pathways and elicit a cascade of immune responses leading to the production of cytokines, which are responsible for the biological effects observed (Goodridge et al. 2011
Two β-glucanases from bacterium Cellulomonas flavigena: expression in Pichia pastoris, properties, biotechnological potential
Published in Preparative Biochemistry & Biotechnology, 2023
Alexander Lisov, Oksana Belova, Zoya Lisova, Alexey Nagel, Andrey Shadrin, Zhanna Andreeva-Kovalevskaya, Maxim Nagornykh, Marina Zakharova, Alexey Leontievsky
1,3-1,4-β-Glucans are a large group of polysaccharides widespread among higher plants, algae, bacteria, and fungi.[1] In general, 1,3-1,4-β-glucans are components of the cell wall, although in some fungi they are exopolysaccharides.[2] Commercially important cereals — wheat, rye, oats, and rice — are especially rich in these substances. Structurally, 1,3-1,4-β-glucans are linear polysaccharides consisting of D-glucopyranosyl residues linked by 1,3 and 1,4 bonds, the proportion of which depends on the source of glucan.[3] 1,3-1,4-β-glucans are degraded by microorganisms using oxidative and hydrolytic enzyme systems. Lytic polysaccharide monooxygenases catalyze the degradation with the addition of oxygen to the polysaccharide backbone of various hemicelluloses, including β-glucans.[4] The hydrolysis of β-glucans is catalyzed by various hydrolases. 1,3-1,4-β-glucans are degraded by endo-β-1,4-glucanases (EC 3.2.1.4) which cleave the 1,4-polysaccharide backbone,[5] β-1,3-glucanase (EC 3.2.1.39) acting on 1,3-β-D-glucosidic bonds,[6] 1,3-β-glucosidase (EC 3.2.1.58) and 1,4-β-glucosidase (EC 3.2.1.21) acting as exohydrolases at 1,4 and 1,3 bonds,[7,8] endo-β-1,3(4)-glucanase (EC 3.2.1.6) randomly hydrolyzing β-1,3-glucan and β-1,3-1,4-glucan.[9] 1,3-1,4-β-glucanases or lichenases (EC 3.2.1.73), like endo-1,4-β-glucanases, catalyze the hydrolysis of 1,4 bonds, but only if the polysaccharide contains 1,3 bonds. These enzymes cleave the 1,4-β bond strictly after the 1,3-β bond.[10] 1,3-1,4-β-glucanases have been found in bacteria, fungi, plants, mollusks.[11–13] According to the carbohydrate-active enzyme database (CAZymes), the enzyme belongs to different glycoside-hydrolas families (http://www.cazy.org/Glycoside-Hydrolases.html). The 1,3-1,4-β-glucanases of the GH5 and GH16 families have been characterized the most extensively.