Merck, A9799-1KG, Agar

General description
Agar is a natural polymer extracted from red alga Rhodophyceae, primarily, consisting of alternative D- and L-galactose units. This type of high gel strength agar is used when a firmer gel is required and mostly suitable for plant cell culture.
Agar is a polysaccharide complex obtained through bleaching and hot water extraction of agarocytes from the red alga Rhodophyceae, found in the Pacific and Indian Oceans and the sea of Japan. The genera Gelidium, Acanthopeltis, Ceramium, Pterocladia and Gracilaria predominate in agar production. Agar is composed of about 70% agarose and 30% agaropectin.
Application
Agar has been used:
in the preparation of laboratory diet to maintain the culture of D. melanogaster wild-type larva
as a high gel strength agar in the seed culture media to grow Arabidopsis thaliana mutant seeds
to construct a tissue-mimicking phantom to test the imaging performance of an ultrasound transducer

Agar has been used:
as a component of the fruit fly diet
as a component of saline-agar for the approximation of gray matter from brain
in in vitro root nodulation assay of Glycine max seeds

Biochem/physiol Actions
Agar with a higher percentage of anhydrous units in the backbone of their chemical composition provides superior mechanical stiffness and strength to the pristine hydrogel.