Preparation of Molecular Biology Grade Agarose from Indian Seaweed Suitable for Nucleic Acid Separation

A more convenient and energy efficient process for the preparation of agarose from Gracilaria and Gelidiella spp.

Gracilaria dura, a marine red alga, occurring sparsely in Indian waters, has been demonstrated to be cultivable in Tamil Nadu. An energy efficient process has been devised to obtain high quality agarose from this seaweed.

• Agarose of desirable specifications can be produced from Gracilaria dura and Gelidiella acerosa of Indian waters through a process that is less capital intensive and more convenient to undertake compared to the prior art and yet gives a product of comparable quality.
• Agarose was prepared in more energy efficient manner by dispensing with the freeze thaw operation.
• Hot seaweed extractive was clarified by centrifugation which process dispensed with the need for Celite and charcoal as clarifying agents. Another advantage is that all the non-ionic surfactants used in the present invention are water soluble which enables their easy removal from the product through simple water washing.
• Surface active agent is recyclable.
• The product, after coagulation from extractive and washing, is made more readily water dispersible by preparing a high concentration of aqueous dispersion and precipitating out with minimum quantity of alcohol to obtain product of desired particle size range thereby dispensing with the need for any pulverization.
• The refined product was suitable for DNA gel electrophoresis at concentrations lower than required with well known commercial products. Another advantage is that the quality of agarose obtained is capable of being stored in plastic containers at least up to 1 year without any deterioration