Asparagopsis

The genus Asparagopsis is known to be an important, highly invasive species. Both species A. armata and A. taxiformis are included on the list of the "worst invasive alien species threatening biodiversity in Europe and Mediterranean Sea".^[8] Asparagopsis armata, a native species from Australia and New Zealand, has spread its population strictly in the temperate region, particularly in Europe. Due to its invasive capacity, the presence of Asparagopsis has an effect on the distribution and abundance of other marine organisms, such as peracarid crustaceans.^[9]

Assemblage of epifaunal communities in the Mediterranean Sea shows a decrease in diversity and homogenised distribution compared with other associated seaweeds present in the area. The structure of the associated macrofauna (species composition, variability among samples, and relative abundance of the species) was also different in a habitat dominated by A. armata and A. taxiformis. This further validates the capacity of genus Asparagopsis to be successful and influential bio-invaders of different habitats.^[10]

The genus Asparagopsis, is used as food for human consumption; for medicinal applications: antibacterial, antimicrobial, antibiotic, and goitre, among others, and cosmetics.^{[11][unreliable medical source?]} It also has the potential to be used in the development of pharmaceuticals.^[12][13]

In Hawaii, dried Asparagopsis taxiformis is considered as a delicacy, and is commonly eaten in poke (fish salad). The seaweed is prepared by cleaning and soaking it overnight in fresh water to remove the bitter iodine taste.^[14]

Like all macroalgae, Asparagopsis contains bromoform, a halogen compound which is known to inhibit methane production in ruminants. It has been shown to convert much of the enteric methane (a powerful greenhouse gas) to energy (and some carbon dioxide) for cattle during normal digestion. Because of its high bromoform content, Asparagopsis has proven to be very effective in inhibiting methane production in livestock. Laboratory experiments have shown that 2–5% of seaweed biomass effectively reduces emissions by 98–100%.^[15][16] A 2020 collaborative study conducted in Australia by Meat and Livestock Australia, CSIRO and James Cook University, confirmed the effectiveness of Asparagopsis in reducing methane emissions, and also showed emissions could be reduced by more than 98% with a 0.2% addition of Asparagopsis to cattle's feed.^[17][18] Emissions were reduced by 80% when Asparagopsis accounted for 3% of the cattle's feed.^[19][20] This could address the increased carbon footprint from the meat industry and mitigate climate issues in the long run.^[21]

Subsequent to the Australian study, CSIRO established FutureFeed Pty Ltd., which holds the global intellectual property (IP) rights for the use of Asparagopsis for livestock feed, with the aim of significantly reducing enteric methane emissions in ruminants.^[22] In 2020, FutureFeed won a Food Planet Prize worth $1 million.^[23] The importance of the product is as a food supplement.^[24]

FutureFeed aims to support this use of Asparagopsis and licenses its IP accordingly. CH4 Global, with research and production facilities in Australia and New Zealand, was the first licensee.^[25] Others include Sea Forest,^[26] also in Australia, Symbrosia^[27] and Blue Ocean Barns^[28] in the US, and Volta Greentech in Sweden.^[29]

Some organizations, including CH4 Global,^[30] Sea Forest,^[31] Blue Ocean Barns,^[32] and Greener Grazing,^[33] are developing methods for the large-scale cultivation of Asparagopsis, either in land-based and ocean hatchery systems.

As interest from the investment community has grown, several companies have obtained series A venture capital financing: Blue Ocean Barns received US$20 million,^[34] CH4 Global received an initial US$13 million,^[35] and Symbrosia US$7 million.^[36]

In 2022–23, Meat & Livestock Australia published a study of the use of Asparagopsis with canola oil as a carrier, in the "finishing diet" of penned Wagyu cattle. It resulted in a 28% reduction in methane (CH4) production. However, there was also persistently reduced liveweight, liveweight gain, and a trend to reduced carcase weight.^[37]