A start-up biotechnology company, Cape Carotene, has become the first in SA to create astaxanthin, an organic antioxidant and colourant. The substance will be used as a feed supplement for farm-reared and ornamental fish, and eventually as a nutritional supplement for humans.
The molecule is one of the most powerful of the 600 naturally occurring carotenoids - fat-soluble antioxidants. It is found in salmon, lobster and prawns, giving them their distinctive pink colour and ensuring their proper development.
In commercial fish and crustacean farms, a synthetic form of astaxanthin is added to feeds. Currently, two companies manufacture synthetic astaxanthin, but it is not considered environmentally friendly.
Cape Carotene is headed by Njodzi Zizhou, who is a graduate of the bioprocessing unit at the department of chemical engineering, University of Cape Town. The company has just been granted R3,761m in funding by the Cape Biotech Trust as part of its mission to boost its nutraceutical cluster of biotech companies in the Northern Cape.
These funds will be used to further develop the technology and to establish a pilot production facility.
The operation is based in Upington, says Zizhou, "because of the ideal weather conditions in the area. Algae, the basis of the product, needs lots of sun to grow and flourish."
The fish that are fed natural astaxanthin have the same vitamin profile as fish found in the wild and, as a result, suffer fewer illnesses.
The algae will be grown in small, shallow ponds for a short period. The algal strain has been derived from fresh-water cultures which have been adapted for commercial use.
Once the development work has been completed, a commercial production facility will be installed. Cape Carotene hopes to export the astaxanthin in the future to European fish farmers and feed manufacturers.
Zizhou says the long- term goal for Cape Carotene is to create astaxanthin as a nutraceutical for human consumption.
Astaxanthin's antioxidant activity has been found to be 10 times more potent than beta carotene and about 100 times more powerful than vitamin E.
It is being marketed as a nutraceutical in the US, where it is being used to treat age-related macular degeneration, a common eye condition.
