Seaweed Polysaccharides

A kelp blade is engineered like a fibre-reinforced composite. Stiff cellulose microfibrils form the skeleton; around them sits a gel matrix of charged polymers, crosslinked by seawater ions and phenolic tannins, that lets the frond bend in the surge without tearing. Take that wall apart in the right order and the matrix is what you are left holding — the alginates, fucoidans, carrageenans, agars, laminarins and ulvans that fill our catalogue. Because each polymer keeps the character of the wall section it came from, Eata Marisource sells seaweed polysaccharides by charge class, chain architecture and source group rather than as a single undifferentiated "seaweed extract".

Everything here starts as cleaned, traceable biomass and is released against a batch COA that names the method behind every figure. If you need grams for a glycoscience screen or tonnes for an industrial blend, the material you qualify on pilot is the material that arrives in production volume.

A Wall Built Like a Composite

Where a polymer sits in the wall decides how easily it comes out, so the architecture is worth a minute of any buyer's time. Brown seaweeds embed cellulose fibrils in an alginate matrix — up to roughly 40% of dry weight — stiffened by calcium crosslinks and phlorotannin complexes, with sulfated fucoidan acting as the interlocking glycan between layers. Red seaweeds build their skeleton from cellulose, mannan or xylan fibrils and fill the gaps with sulfated galactans: agar, carrageenan and porphyran, plus a glycoprotein domain. Green seaweeds such as Ulva keep a plant-like cellulose web inside a porous matrix rich in ulvan, with minor glucuronans and xyloglucans. Laminarin breaks the pattern — it is a storage β-glucan held inside the cell, not a wall polymer at all, which is why it extracts under far milder conditions than its neighbours.

Charge Is the Real Sorting Line

Group the range by charge instead of by name and a cleaner picture appears. One camp carries sulfate esters — fucoidan, the carrageenans, ulvan, porphyran — which is what makes these polymers interact with proteins and metal ions and underlies most of the cell-signalling literature. A second camp is carboxyl chemistry: alginate's uronic acids bind calcium in the famous egg-box arrangement, and that same anionic character drives bead-making and encapsulation work. The third camp is close to neutral — agarose, laminarin — valued precisely because they stay out of the electrostatics. Conductometric titration lets us put a number on each of these charge populations, and it is one of the quiet backbone tests behind every lot we release.

The Range, Organised by Chemistry

Individual families have their own catalogue pages with deeper specifications; the table above is the map. Where a project needs a blend — a kappa–LBG gel system, an alginate–fucoidan polyelectrolyte pair — the fractions are cut from lots whose chemistries are already on file, so the combination behaves the same way next quarter.

One Polymer, Many Datasheets

No single number describes any of these materials, and the published literature shows how wide the spread runs. Alginate content alone swings from 16% to more than 40% of dry biomass depending on species, and extracted M/G ratios have been reported anywhere between 0.47 and 1.85 within the same genus — high-M chains pour viscosity, high-G chains build gel strength. Fucoidan molecular weight spans from about 7 kDa to well past 2,000 kDa, with sulfation from 5% to 38%. Carrageenan viscosities read 5–800 cP at the standard 1.5% and 75 °C; ulvan sits at 18–100 cP at 1.6%. Even seaweed cellulose varies three-fold in crystallinity between species. This is exactly why we quote figures lot by lot: an average would describe a material that exists in no drum on our floor.

Rheology Separates the Family Fastest

Ask five polymers to form a gel and you will get five different answers, which makes small-amplitude oscillatory data the quickest honest comparison between them. Published benchmarks we build our grades around:

Where These Materials End Up

• Textile printing — alginate thickeners carry reactive dyes onto cotton, silk and nylon with the sharp definition and high colour yield that starch pastes never matched; global alginate output runs near 30,000 tonnes a year from roughly 750,000 tonnes of wet weed
• Water-treatment studies — charged matrices tested as flocculant aids and heavy-metal sorbents, screened in jar-test rigs before any pilot column is built
• Paper, ceramics and welding consumables — film-forming binders and surface sizing agents where a natural polyelectrolyte outperforms starch on strength
• Laboratory research — electrophoresis media, encapsulation matrices, bioinks, culture gels and glycoscience reference materials
• Personal-care and cosmetic R&D — rheology modifiers, film formers and marine-active bases for serums and masks
• Feed and crop science — immunology and elicitation studies built on laminarin, fucoidan and ulvan fractions at documented inclusion rates

How a Lot Gets Released

• Identity by FTIR against a retained reference for every polymer family
• Monosaccharide composition after TFA hydrolysis, by HPLC, GC or HPAEC-PAD
• Sulfate by ion chromatography or turbidimetry; uronic acid by colorimetric and conductometric methods
• M/G ratio by ¹H NMR on alginate grades; EEO on agarose
• GPC/SEC runs on the whole chain population, and the size-exclusion trace ships with the COA
• Viscosity measured at your working concentration, not a house default; gel strength and texture on gelling grades, cast under standard conditions
• Karl Fischer moisture, ash and insoluble matter, pH, particle size and bulk density
• Heavy metals by ICP-MS plus iodine and arsenic speciation; full microbial panel; traceability back to harvest region and processor

Formats, Packs and Custom Work

• Research packs from 100 g in glass bottles or amber vials; kilo and 5 kg foil bags for pilot work; production volumes go out in 25 kg fibre drums, each lined with double poly
• Powder, granulated, low-dust or tableted forms; aqueous concentrates at agreed solids for in-line dosing; blended systems made to your ratio
• Hygroscopic powders are packed to be resealed quickly; store cool, dry and dark and sealed stock holds its specification for 24 months
• COA, TDS and safety data sheet travel with every consignment; origin documentation on request

A good share of what leaves here began as somebody's awkward specification: a viscosity window between two catalogue grades, a sulfate floor on a depolymerised cut, an alginate–ulvan blend nobody stocks. Send the target and the reason behind it — we develop against your in-house method, prove it on pilot batches, and hold the recipe constant from first kilogram to full production.

For Research or Industrial Raw Materials, Not For Personal Medical Use!