[adimed]

Marine algae are ecologically significant as primary producers and have been utilized economically as medicines and food for generations. Nowadays, numerous species of marine algae supply not only food but also with extracts such as agar, alginates and carrageenans. These extracts are utilized in various foods, cosmetic, pharmaceutical and industrial purposes.

Red algae (Rhodophyta)

Carrageenan is prepared from various species of red algae such as Chondrus crispus , Mastocarpus stellatus and Eucheuma. It is similar to agar, but is required in greater concentrations to form gels. It is utilized in the stabilization of ice cream, chocolates, milk, instant puddings, egg nog, sherbets, creamed soups, frostings and so on. Industrial applications of carrageenan involves its utilization in Enzyme immobilization, Air freshener gels, Tertiary oil treatment, Electrophoresis media, Cleaners, Chromatographic media etc. The pharmaceutical and medical application of it includes its utilization in Capsules and tablets, creams and lotions, Laxatives, Ulcer products, Toothpastes and shampoos.

Agar is prepared from different species of red algae such as Gracilaria, Gelidium, Ahnfeltia and Pterocladia. It is a colloidal substance that is utilized as thickening, stabilizing and suspending agent. It is also noticed for its unique capability to form thermally reversible gels at lower temperatures. The maximum utilization of agar is in association with food and in pharmaceutical industry (as an inert carrier for drug products where slower release of the drug is required or used as a laxative). It is used in mycology and bacteriology as a stiffening agent in various growth media. Agar is used sometimes as a substitute for gelatine in food, anti-drying substance in pastry, bread and also for thickening and gelling purposes. It is utilized in the manufacturing of mayonnaise, frozen dairy products, processed cheese and creams. Agar is used as an ingredient of cosmetic skin preparations, lotions and ointments and also in dental impression moulds, photographic film, shaving soaps and tanning industry.