Ose, 0.25 glucose, and 0.3 to 16 xylose and mannose. As a heterogeneous polymer, fucoidan exhibits considerable structural diversity that makes it tough to draw basic conclusions. In addition, its structure can’t be described solely determined by monosaccharide composition.Figure four. Structure and biological effects of fucoidan (A: Ascophyllum nodosum and Fucus vesiculosus; B: Saccharina japonica, adapted from literature [11921]).The structural variety of fucoidans will be to a large extent related to the distinct varieties of brown algae they may be found in. Usually, (13) and/or (14) glycosidic bonds constitute the primary chain on the macromolecules, dominating in most backbone structures. The presence of sulfate groups at the C-2, C-4 and or C-3 position is another crucial function [94,12227]. Due to the structural heterogeneity of fucoidans, the degradation of fucoidan demands a sizable set of enzymes of different activities and specificities [128]. Fucoidanase are mostly from marine bacteria, invertebrates and in some cases fungi. Related for the above mentioned polysaccharide-degrading enzymes, endo-type fucoidanase pro-Mar. Drugs 2021, 19,ten ofduce fuco-oligosaccharides even though exo-type fucosidase results in the formation of mono- or oligosaccharides with a modest degree of polymerization [129]. Natalie et al. purified a brand new fucoidanase and hydrolyzed fucoidan without the need of desulfation to kind oligosaccharides ranging from ten to two fucose units plus fucose [130]. Dong et al. discovered a brand new -L-fucosidase from marine bacterium Wenyingzhuangia Tianeptine sodium salt Neuronal Signaling fucanilytica, and discovered that Alf1_Wf was capable of hydrolyzing -1,4-fucosidic linkage and synthetic substrate. Besides, Alf1_Wf could act on partially degraded fucoidan [131]. When compared with other brown polysaccharides, there are actually few research around the enzymatic degradation of fucoidan and the function of fucooligosaccharides, whereas the functional investigation of biological activities, including anti-obesity, antivirus, antitumor, antidiabetic, and antioxidative effects has been broadly established. It can be typically believed that fucoidan can become an essential substance within the functional meals and nutrition and wellness industries [132,133]. four.1. Antitumor Activity Fucoidan has considerable antitumor activity against liver cancer, stomach cancer, cervical cancer, lung cancer, and breast cancer [113,13438]. The underlying mechanism involves the inhibition of tumor cell proliferation, stimulating tumor cell apoptosis, blocking tumor cell metastasis, and enhancing numerous immune responses [136,13941]. Low molecular weight fucoidan (LMWF), as an illustration, AS-0141 site triggers G1-block and apoptosis in human colon cancer cells (HCT116 cells) by way of ap53-independent mechanisms [142]. By way of the assessment of microtubule-associated proteins and also the accumulation of Beclin-1, fucoidan is also identified to induce autophagy in human gastric cancer cells (AGS cells) [143]. The polysaccharide induces the apoptosis of HTLV-1-infected T-cell lines mediated by cytostatics that downregulate apoptosis protein-2. The use of fucoidan in vivo therefore severely inhibits the tumor growth of subcutaneously transplanted HTHT-1-infected T-cell lines in immunodeficient mice [138]. Additionally, fucoidan activates the caspase-independent apoptotic pathway in MCF-7 cancer cells by activating ROS-mediated MAP kinase and regulating the mitochondrial pathway mediated by Bcl-2 family members proteins [144]. Similarly, fucoidan has shown antitumor activity against PC-3 (prostate cancer), HeLa.
