Microalgae are, literally, “little seaweeds.” They are living microorganisms that are single-celled or colonial, like bacteria and protozoa. They are different, however, from most other microbes in that they use the energy of sunlight to make their own food by photosynthesis. Microalgae are the primitive ancestors of plants, and microalgae “invented” photosynthesis billions of years ago. Microalgae are enormously diverse, in terms of their physical appearance and internal chemistry. They can be found in the sea, in freshwater, in soil, …
Seaweed Aquaculture: An Introduction
The seaweeds (or sea vegetables) are a large and diverse group of marine macroalgae that can be found in intertidal and subtidal coastal regions around the world. Like land plants, they utilize photosynthesis to convert inorganic nutrients into organic biomass, an important link that provides food, shelter, and habitat for other organisms. Seaweeds are simple in their structural compositions because they take up nutrients into their blades or fronds directly from the seawater, unlike more complex land plants which take …
Seaweed Aquaculture: Kelp
Kelp is a healthy and nutritious sea vegetable that is high in fiber, vitamins, and minerals, including vitamin C, vitamin K, iron, calcium, iodine, and magnesium. Kelp has long been part of the diet of Asian cultures, and, in fact, Saccharina japonica (a relative of our native Saccharina latissima) is the number one aquacultured species worldwide by weight. Although the majority of kelp marketed in the US is harvested from the wild, the development of a kelp culture industry, …
Seaweed Aquaculture: Gracilaria
Gracilaria
The genus Gracilaria, in the Phylum Rhodophyta (the red seaweeds), contains over 100 species found around the world, and many are wild harvested and cultivated for food and the phycocolloid agar. Known as ogo or ogonori in Japan and Hawaii, Gracilaria is a popular ingredient in salads, usually sold fresh or salted. Agar is a gel-forming polysaccharide extracted from the cell walls of Gracilaria species, and is especially important in the food and microbiological industries. Gracilaria is a …