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Seaweeds are a significant component of current marine aquaculture production and will play an increasing role in global food security as the human population increases rapidly over the next 30 years. Seaweed farming is analogous to plant-based agriculture except that the crop is cultured in a marine environment. It also differs from agriculture in that seaweeds do not require tillable land, fertilization, or freshwater, which are resources that may ultimately constrain the expansion of agriculture. Seaweeds are converted into a variety of goods, such as food and nutritional supplements for humans and livestock, fertilizer, unique biochemicals, and biofuels. Wild and cultured seaweed also offer multiple ecosystem services, such as bioremediation for coastal pollution, localized control of ocean acidification, mitigation of climate change, and habitat for other marine organisms. Incorporation of seaweeds into marine aquaculture farms in the United States is, however, not without its challenges. Seaweed is an unconventional food which necessitates establishing product acceptability, creating a sustained market, and then balancing demand with a consistent supply for long term economic profitability. Seaweed farms also need to be developed in a manner that is compatible with wild capture fisheries, marine mammal migrations, and other users of the marine environment. A comprehensive understanding of the role that cultured seaweeds play in the marine ecosystem is necessary in order to determine not only the economic value of the goods produced but also the ecosystem services offered by marine farming activities. This will result in a better understanding of how an ecosystem approach to aquaculture incorporates the role and need for both the goods and services these macroalgae will provide.

Prospecting macroalgae (seaweeds) as feedstocks for bioconversion into biofuels and commodity chemical compounds is limited primarily by the availability of tractable microorganisms that can metabolize alginate polysaccharides. Here, we present the discovery of a 36–kilo–base pair DNA fragment from Vibrio splendidus encoding enzymes for alginate transport and metabolism.

The genomic integration of this ensemble, together with an engineered system for extracellular alginate depolymerization, generated a microbial platform that can simultaneously degrade, uptake, and metabolize alginate. When further engineered for ethanol synthesis, this platform enables bioethanol production directly from macroalgae via a consolidated process, achieving a titer of 4.7% volume/volume and a yield of 0.281 weight ethanol/weight dry macroalgae (equivalent to ~80% of the maximum theoretical yield from the sugar composition in macroalgae).

Together with observations on the various modes of practice of regular practitioners, and others in the present day, enabling the reader at one view to become acquainted with every method now pursuing for the curse of this malady. 

While some investigators have attempted to use isozyme electrophoresis to gain information on the genetics of brown algae, most have reported unsatisfactory results. Through exhaustive screening and modification of sample preparation techniques, gel and tray buffers systems, plus staining recipes, we have developed procedures that consistently provide scorable bands for over 20 enzyme systems in several laminarian algae. We have used our procedures to examine geographically diverse populations of Laminaria saccharina and L. longicruris, as well as L. digitata, L. groenlandica, Agarum cribrosum, Alaria esculenta, Chorda tomentosa, and Macrocystis pyrifera. Overall, these kelp species seem to have an extremely low degree of enzyme solymorphism, both within and between populations. While some rare alleles occurred in several enzyme systems, only 3–5 loci were found to be polymorphic. Our results are consistent with the few reported studies that have used molecular genetic techniques to look at the intraspecific variability of laminarian algae. We suggest that at the species level the Laminariales, and perhaps other groups of brown algae, are genetically extremely conservative as compared to other divisions of plants. We further suggest that isozyme electrophoresis provides a quick and useful tool for algal population genetic studies.