Structure of β-Glucan Oligomer from Laminarin and Its Effect on Human Monocytes to Inhibit the Proliferation of U937 Cells

Abstract

We analyzed the human monocyte-stimulating ability of laminarin from Eisenia bicyclis, lichenan from Cetraria islandica, and their oligomers depolymerized with endo-1,3-beta-glucanase from Arthrobacter sp. The respective beta-glucan oligomers with different degrees of polymerization (DP) were fractionated from hydrolytic products of laminarin and lichenan using gel-filtration chromatography. The monocyte-conditioned medium pre-cultured in the presence of a fraction of beta-glucan oligomer (DP>/=8) from laminarin exhibited inhibitory activity against the proliferation of human myeloid leukemia U937 cells, while those pre-cultured with other beta-glucan oligomers and the original laminarin and lichenan showed little or no activity. NMR analysis indicated that the beta-glucan oligomer (DP>/=8) has an average DP value of 13, and its ratio of beta-1,3- to beta-1,6-linkages in glucopyranose units was estimated to be 1.3:1. These results indicate that the beta-1,3-glucan oligomer with a higher content of beta-1,6-linkage stimulates monocytes to inhibit the proliferation of U937 cells.

Production, purification and characterization of a thermostable β-1,3-glucanase (laminarinase) produced by Moniliophthora perniciosa

“…Enzymes that catalyze depolymerization or selective modification of cereal β-glucans are of biotechnological and biomedical importance because they have shown a significant potential application in malting and brewing processes (Konig et al 2002, Mannonen et al 1997, biological control of plant pathogens (De La Cruz et al 1995), fungal and yeast cell wall degradation (Pitson et al 1993), animal feed (Konig et al 2002) and medical fields (Pang et al 2005.…”

Enzymatic properties and the primary structure of a β-1,3-glucanase from the digestive fluid of the Pacific abalone Haliotis discus hannai

“…Among these seaweeds' polysaccharides, laminarin seems to be the most potential glucose source for abalone since laminarin is a major storage polysaccharide consisting of -1,3-linked glucose main chains possessing occasional -1-6-linked glucose branches (Maeda and Nisizawa, 1967;Pang et al, 2005). Previously, a laminarin-degrading enzyme, i.e., endo--1,3-glucanase that hydrolyzes -1,3-glucoside linkages of laminarin, was isolated from hepatopancreas of the ormer Haliotis tuberculata (Lépagnol-Descamps et al, 1998).…”

Purification and Characterization of a Novel Exo-β-1,3-1,6-glucanase from the Fruiting Body of the Edible Mushroom Enoki (Flammulina velutipes)

“…Many beneficial bioactivities have been found among the constituents of edible mushrooms. -1,3-Glucans and their hydrolysate oligosaccharides extracted from the cell wall exhibit significant bioactivity, e.g., anti-diabetic, 1) anti-apoptosis, 2) monocyte stimulation, 3,4) and anti-tumor. [5][6][7][8][9] Cell-wall autolysis and reconstruction are essential processes during fruiting body development in basidiomycetous fungi.…”