Description
Low acyl gellan gum for plant tissue culture. Clear, firm and sliceable. The industry standard gelling agent for micropropagation, agar replacement and clean visual monitoring of cultures.
Rootlab Gellan Gum LA is a low acyl gellan gum, the deacylated form of the polysaccharide produced by fermentation of Sphingomonas elodea. Removing the glyceryl and acetyl side groups lets the polymer chains pack into ordered double helices, which cross link into a rigid, optically clear network. That is what gives low acyl gellan the firm, brittle, scalpel friendly texture most tissue culture protocols are built around.
Because it is fermented rather than harvested from seaweed, you get batch to batch consistency that agar cannot match, at roughly half the usage rate.
Why low acyl
Optically clear. Watch root architecture, callus development and early contamination without opening the vessel.
Firm and sliceable. Cuts cleanly under a scalpel, holds its shape through subculture and replating.
Low usage rate. 2 to 4 g/L against 6 to 12 g/L for agar, so a container goes considerably further.
Heat stable once set. Close to thermally irreversible with adequate cations present, so it will not slump in a warm incubation room.
Consistent. Fermentation derived, so no seasonal or seaweed source variation.
Clean. Low residual protein and trace element load, which matters for sensitive explants prone to browning.
Recommended usage
Standard herbaceous species: 2.0 to 3.0 g/L
Orchids and general micropropagation: 2.5 to 3.5 g/L
Woody species and firmer matrices: 3.5 to 4.5 g/L
Microbiological and agar replacement work: 4.0 to 8.0 g/L depending on required firmness
Preparation
Disperse the powder into cold or room temperature water while stirring vigorously, to avoid clumping. Add it before the salts where possible.
Add media salts, sugar and supplements, then adjust pH to 5.4 to 5.8.
Autoclave at 121ยฐC, 15 psi, for 15 to 20 minutes. The powder needs to reach above 90ยฐC to hydrate fully.
Dispense while hot. The gel sets on cooling through roughly 30 to 50ยฐC.
A note on cations. Low acyl gellan needs divalent cations, calcium and magnesium, to gel properly. Standard MS, WPM, Knudson C and Vacin and Went formulations supply plenty, so in normal use this is not something you need to think about. It only becomes an issue on low salt or heavily customised media, where you can end up with a weak gel. If that happens, adding 0.5 to 1.0 mM calcium chloride or magnesium sulfate will usually sort it.
Applications
Shoot multiplication, rooting and general micropropagation
Orchid seed sowing, flasking and replating
Banana, grape, berry and fruit tree tissue culture
Callus induction and somatic embryogenesis
Clinical and bacteriological media as an agar substitute
Any protocol where visual monitoring through the gel matters
Product details
Type: low acyl gellan gum
Synonyms: Gelrite, Phytagel, Gelzan
CAS No. 71010-52-1
Appearance: off white free flowing powder
Working concentration: 2 to 4 g/L for tissue culture
Gel setting temperature: approximately 30 to 50ยฐC
Dissolution temperature: 90ยฐC or above
Gel strength: [insert from CoA] g/cmยฒ at 0.2 percent with standard cations
Loss on drying: [insert from CoA]
Particle size: [insert from CoA]
Gluten free, soy allergen free, animal free, vegan
Storage: 15 to 30ยฐC, container sealed, cool and dry
Shelf life: 18 months from manufacture, see label for expiry
Made and packed in Australia
Considering high acyl instead? See Rootlab Gellan Gum HA for a softer, more elastic, syneresis resistant matrix.
