Fucoidans from brown seaweeds: an update on structures, extraction techniques and use of enzymes as tools for structural elucidation

In the paper

“Structural integrity of the polysaccharide was best conserved at low acid treatment.”

In the paper

“A maximal fucoidan yield of y7% was achieved by the optimal extraction procedure of: 0.03 M HCl, 90 uC, 4 h.”

In the paper

“The HPAEC-PAD analysis of the TFA hydrolysate of S. henslowianum confirmed that fucose, galactose, and glucuronic acid were the major constituents of the extracted polysaccharides obtained by the optimized method.3”

What the sources say

• Not checked yetcites [3] source

In the paper

“The use of 0.2 M HCl apparently broke the integrity of the polysaccharide molecules resulting in a decline of fucose at elevated time and temperature.3”

What the sources say

• Not checked yetcites [3] source

In the paper

“the structural and compositional traits, and possibly the bioactivity, of the fucoidan polysaccharides are significantly influenced by the extraction parameters.”

• Also stated in: § 3.1 Influence of extraction parameters on fucoidan yield and composition · boosted

  “The data demonstrate the vulnerability of fucoidan structures to harsh extraction conditions and confirm that the extraction method significantly influences the yields and not least the composition of the extracted polysaccharides.”

What the sources say

• Not checked yetcites [3] source

In the paper

“Several of the fucoidan structures reported in the literature have also contained small amounts of various other monosaccharides e.g.glucose, galactose, xylose, and/or mannose. 1”

What the sources say

• Not checked yetcites [1] source

In the paper

“The differences caused by differences in extraction methodologies obviously may have major bearings on the results when the fucoidan polysaccharide products are being evaluated for biological activity.”

In the paper

“Likewise, the enzymatic treatment confirmed that the main fucoidan structural unit from this brown seaweed Fucus spp.consists of repeating di-saccharide units of [A3)-a-L-Fucp-(2,4di-SO 3 2 )-(1A4)-a-L-Fucp-(2SO 3 2 )-(1A].35”

What the sources say

• Not checked yetcites [35] source

In the paper

“The variations in the reported structural properties of fucoidans from different brown seaweed species clearly confirm the natural biodiversity of fucoidans as exemplified by the structures found in different seaweed taxonomical orders, notably Fucales, Laminariales and Chordariales (Table 1).”

In the paper

“The bioactivities of fucoidans are related to their structural make-up, monosaccharide composition, sulfate content, position of sulfate ester groups, and molecular weight.2”

What the sources say

• Not checked yetcites [2] source

In the paper

“a-L-fucosidase only catalyses the cleavage the a-L-fucosyl linkages at the nonreducing termini, releasing fucose from the fucose-backbone structure in fucoidans (Enzyme type 3, Fig. 1).”

What the sources say

• Not checked yetcites [32] source
• Not checked yetcites [33] source
• Not checked yetcites [34] source

In the paper

“However, as compared to the quite advanced stage of development of designed enzyme mixtures for hydrolysis of complex plant materials or heterogenous plant cell wall polysaccharides, 39,40 only various crude, commercial enzyme mixtures, designed for plant material processing, have been used as hydrolysis aids for extraction of brown seaweed biofunctional polysaccharide fractions.5,41”

What the sources say

• Not checked yetcites [39] source
• Not checked yetcites [40] source
• Not checked yetcites [5] source

In the paper

“Hence, the published structural data for algal fucoidans confirm that there is no consistent basic structure of ''fucoidan''.”

In the paper

“In contrast, the sulfated ''pseudo''-fucoidan polysaccharides extracted from some other species in the order Fucales, such as e.g.Sargassum stenophyllum, are built mainly of b(1A6)-D-galactose and/or b(1A2)-D-mannose units in the polysaccharide backbone with branching points formed by a(1A3) and/or a(1A4)-L-fucose, a(1A4)-D-glucuronic acid, terminal b-D-xylose, and sometimes a(1A4)-D-glucose.”

What the sources say

• Not checked yetcites [11] source

In the paper

“Distinct structures can be isolated by different extraction conditions.2,5”

What the sources say

• Not checked yetcites [2] source
• Not checked yetcites [5] source

In the paper

“A study of the fucosidase action on fucoidan polysaccharides from Fucus distichus has thus established that the native fucoidan polysaccharides contain blocks of acetylated and partially sulfated repeating units.35”

What the sources say

• Not checked yetcites [35] source

In the paper

“Enzyme-assisted extraction of fucoidan polysaccharides has recently been proposed, 5 using enzymes that do not catalyze the hydrolysis of the target fucoidan polysaccharides.”

What the sources say

• Not checked yetcites [5] source

In the paper

“Glucuronic acid (GlcA) has also been detected and found to be an integral part of the non-sulfated fucooligosaccharides: Fuc-(1A3)-GlcA, Fuc-(1A4)-Fuc-(1A3)-GlcA, Fuc-(1A3)-Fuc-(1A3)-GlcA respectively.13”

What the sources say

• Not checked yetcites [13] source

In the paper

“Classical extraction of fucoidans from brown seaweeds involves multi-step extended aqueous extractions, usually with hot acid (hydrochloric acid), 3”

What the sources say

• Not checked yetcites [3] source

In the paper

“Therefore the initial suggestion that fucoidan obtained from F. vesiculosus (Fucales) was built of a(1A2) linked L-fucopyranosyl has been revised.16”

What the sources say

• Not checked yetcites [16] source

In the paper

“Based on an analysis of the extraction methods employed in different studies, it has become clear that the use of different acids-or no acid at all-and differences in extraction time and temperature during the extraction and purification treatments of fucoidans, have generated very diverse compositional results and structural suggestions for fucoidan polysaccharides 1 (Tables 2 and 3).”

What the sources say

• Not checked yetcites [1] source

In the paper

“The problem of elucidating the structural details of fucoidans has been exacerbated by the use of many different extraction techniques.”

In the paper

“This indicated that the higher acid levels might have caused a loosening of the cell wall matrix allowing local penetration of the acid into the fucoidan.”

In the paper

“More detailed analysis of F. evanescens by MALDI-TOF and tandem ESI mass spectrometry has also revealed the presence of minor components such as mixed mono-sulfated fucooligosaccharides containing both 2-O-and 4-O-sulfated (1A4) bonded xylose and galactose residues: Xyl-(1A4)-Fuc, Gal-(1A4)-Fuc, Gal-(1A4)-Gal-(1A4)-Fuc, Gal-(1A4)-Gal.”

What the sources say

• Not checked yetcites [13] source

In the paper

“Hence, stimulation with IL-2 and IL-12 may promote the secretion of IFN-c by NK cells, probably via enhanced NK cell activity by fucoidan.”

What the sources say

• Not checked yetcites [50] source

In the paper

“As a pharmaceutical or nutraceutical ingredient, fucoidans clearly offer distinctive possibilities for immuno-modulation and anti-cancer effects.”

In the paper

“Bacteria of the genera Cytophaga and Alteromonas/Pseudoalteromonas exhibited the highest fucoidanase activities.36”

What the sources say

• Not checked yetcites [36] source

In the paper

“The L-fucopyranose backbone of the fucoidan extracted from A. nodosum and F. vesiculosus is connected by alternating a(1A3) and a(1A4) linkages with sulfate substituted at the 2-and 3-position of the fucose residues”

In the paper

“the other type of fucoidanase catalyses the glycosidic bonds (both a(1A3)-, a(1A4)-bonds) in the fucose-back bone via random endo-type hydrolysis”

What the sources say

• Not checked yetcites [32] source
• Not checked yetcites [33] source
• Not checked yetcites [34] source

In the paper

“The direct anti-proliferative effects of fucoidan polysaccharides against certain cancer cells have been shown in vitro using cell viability analysis.”

In the paper

“Fucoidan structures of brown seaweeds from the orders Fucales and Chordariales are known to differ from those of Laminariales. 1”

What the sources say

• Not checked yetcites [1] source

In the paper

“From the information available about enzymes able to catalyse modification of fucoidans from brown seaweeds, it appears that these enzymes may have a broad spectrum of biological roles and potential applications.”

In the paper

“Histochemical staining showed morphological changes of melanoma cells after exposure to the fucoidans and were indicative of crude fucoidan induced apoptosis.45”

What the sources say

• Not checked yetcites [45] source

In the paper

“one type of fucoidanase catalyses the cleavage of small, low molecular weight oligosaccharides from the end of the fucoidan backbone chains”

What the sources say

• Not checked yetcites [32] source
• Not checked yetcites [33] source
• Not checked yetcites [34] source

In the paper

“protect the elastic fiber network in human skin culture; 53”

What the sources say

• Not checked yetcites [53]

In the paper

“Fucoidan polysaccharides have been reported to have potential beneficial bioactive functions, including anti-proliferative effects on certain types of cancer cells.45”

What the sources say

• Not checked yetcites [45] source

In the paper

“Both FCSPs from Sargassum sp. and more classic fucoidan polysaccahrides from Fucus vesiculosus significantly decreased the viable number of lung carcinoma and melanoma cells in vitro in a doseresponse fashion.45”

What the sources say

• Not checked yetcites [45] source

In the paper

“A consistent extraction process is also a prerequisite for elucidating the structurefunction relationship that promotes these biological properties.”

In the paper

“while fucoidan of Chorda filum and Laminaria saccharina consist of a poly-a-(1A3)-fucopyranoside backbone with sulfate mainly at C-4 and sometimes at the C-2 position (Table 1).”

In the paper

“Fucoidanase from the marine bacterium Fucanobacter lyticus has shown to exhibit extracellular endo-fucoidanase degrading activity on fucoidan polysaccharides obtained from brown seaweed in the order of Laminariales but not Fucales and Chordariales indicating specificity of an endo-1,3-a-fucoidanase. 44”

What the sources say

• Not checked yetcites [44] source

In the paper

“and to have potential for inclusion in lotion as a natural whitening agent.54”

What the sources say

• Not checked yetcites [54]

In the paper

“Nevertheless, it appears that the anti-cancer activity of fucoidans is not a function of a single specific structural trait but a combination of many factors such as the amount of sulfate groups, the monosaccharide composition, and the types of linkages of the sugar residues.1,30”

What the sources say

• Not checked yetcites [1] source
• Not checked yetcites [30] source

In the paper

“Fucoidanase activities were first detected in several different marine microorganisms, including marine bacteria such as Vibrio sp., Alteromonas sp., Pseudoalteromonas sp., and bacteria of the family Flavobacteriaceae.32,36,37,43”

What the sources say

• Not checked yetcites [32] source
• Not checked yetcites [36] source
• Not checked yetcites [37] source
• Not checked yetcites [43] source

In the paper

“As a consequence, no pharmaceutical, dermatological, nutraceutical or other applications have as yet been officially approved for these polysaccharides or their lower molar mass oligosaccharide derivatives.”

In the paper

“However, the exact structural element(s) in the fucoidan molecules being responsible for these potentially protective activities are still unidentified.”

In the paper

“Some findings indicate that the antitumor activity of fucoidan is a result of an indirect effect which may be associated with a significant enhancement of the cytolytic activity of natural killer (NK) cells augmented by increased production of macrophage-mediated immune response signaling molecules, 50,51 namely interleukins (IL)-2, IFN-c and IL-12.50”

What the sources say

• Not checked yetcites [50] source
• Not checked yetcites [51] source

In the paper

“Thus the extraction process employed for the fucoidans is crucially important for maintaining the structural integrity and the relevant structural features required for specific biological activity.”

In the paper

“It is also clear that acid treatment used as the major step/steps in the extraction of fucoidans causes degradation and affects the integrity of overall fucoidan makeup.”

In the paper

“It has been convincingly shown that the extraction treatment employed affects the composition and thus the structural features of the fucoidan substances.”

In the paper

“Preservation of the structural integrity of the fucoidan molecules appears crucial for maintaining their biological properties.”

In the paper

“The extraction methodology employed may thus significantly affect the results obtained when the fucoidan products are being evaluated for biological activity.”