Seaweed: A rich source of vitamins and bioactive compounds

Seaweed: A rich source of vitamins and bioactive compounds

Awareness of the potential health benefits of seaweed – not just for human consumption– is gathering apace, whereby selected seaweed species are now being added to aquaculture and agriculture feed with resulting benefits. One reason for this is that seaweed is a significant source of vitamins and other interesting compounds that have a number of biological functions.

Biological Functions of Vitamins

Kelp Brown

Kelp Seaweed

Vitamins can be divided into those that are either water or fatsoluble. Water-soluble vitamins include both B-complex vitamins and vitamin C. The B-complex vitamins are the largest group and have roles associated with metabolism, muscle tone, cell growth and the nervous system. For example, Nori (Porphyra sp.) and sea lettuce (Ulva sp.) are good sources of vitamin B12 which has an important role in DNA synthesis. Vitamin C is a water-soluble vitamin that is important for gum health, iron absorption and resistance to infection.

Fat-soluble vitamins include vitamin A, D, E and K. Vitamin A (retinol) plays an important role in bone growth, tooth development, reproduction and cell division. Vitamin D, another fat-soluble vitamin, is important for bone growth and maintenance. Vitamins E and K also have a number of biological functions including antioxidant activity and blood clotting. In addition to their biochemical functions and antioxidant activity, seaweed-derived vitamins have been demonstrated to have other health benefits such as reducing hypertension, preventing cardiovascular disease and reducing the risk of cancer.

Factors Affecting Vitamin Content 

Although seaweed contains both water and fat-soluble vitamins, the vitamin composition of seaweed is variable and depends on a number of factors. For example, evidence exits of seasonal variation in the vitamin content of the seaweed Eisenia arborea, where fat-soluble vitamins follow a different pattern to those that are water-soluble. Another factor affecting seaweed vitamin content is light exposure, as plants growing in bright light can contain higher levels of some vitamins.

Seaweed species is another critical factor which can affect vitamin composition. For example, the level of niacin (vitamin B3) in some brown seaweeds (e.g. Laminaria sp.) is approximately one tenth the level found in the red seaweed, Porphyra tenera. Other factors that can influence vitamin content include geographical location, salinity and sea temperature. Vitamin content can also be affected by processing as both heat and dehydration can have a significant effect on the vitamin levels.

Seaweed-Derived Compounds

In addition to vitamins, seaweed also contains bioactive compounds which have been proven to have antibiotic; antiviral; antimicrobial; mitogenic anti-inflammatory; anti-adhesion; ACE-inhibitory; antioxidant; anticancer and antithrombotic effects. These bioactive compounds include polysaccharides; proteins; amino acids; pigments phenolic compounds and sterols. The levels of these bioactive compounds also depend on factors such as species, geographical location and season.

Incorporating Seaweed into Feed

Ocean Harvest Technology’s fully sustainable feed product ‘OceanFeed™’ is a specially selected, unique blend that harnesses the bioactive compounds and vitamins present in seaweed. OceanFeed™ therefore offers a natural, fully sustainable feed ingredient formula for the aquaculture and animal feed sectors that can replace costly synthetic ingredients.

Researcher working in the OHT Lab

Researcher working in the OHT Lab

by Simon Faulkner

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Seaweed – an untapped source of protein and bioactive compounds for aquaculture

Seaweed – an untapped source of protein and bioactive compounds for aquaculture

Seaweed is fast gaining a reputation as the ideal sustainable food source. Certainly, the nutritional properties of seaweeds are both unique and interesting, with some seaweeds having protein levels as high as 47%. Seaweed, therefore, represents an untapped source of protein and has great future potential.

As the global population continues to rise, the need for sustainable, alternative sources of protein also increases. In fact, it is estimated that the worldwide requirement for food will increase up to 50% by 2030, thus highlighting the absolute need for sustainable development. Recently, Ocean Harvest Technology has worked in collaboration with a number of research institutes to evaluate the use of different seaweeds as a sustainable protein source for aquaculture.

Why Seaweed Protein?

Protein is the most expensive constituent of fish feed whereby global expenditure exceeds €1bn per annum. Fishmeal is a high-protein animal feed used extensively in aquaculture but uses wild fish stocks to feed farmed fish and is an unsustainable feed resource. The ability of fishmeal supply to meet future demand is a massive global concern – especially given that aquaculture production is growing at a rate of nearly 9% per annum.

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Ocean Harvest Technology Produce

As wild fish stocks decline, the aquaculture industry faces a massive challenge to identify cost-effective and environmentally-friendly alternatives to fishmeal on which it is so heavily reliant. Seaweed protein has the potential to provide a solution to this problem as it is relatively underexploited, contains high amounts of protein and can be cultured in a sustainable, environmentally-friendly manner.

Essential Nutrients

Proteins are an important source of energy, present in all cells and are an essential component of most biochemical processes. Proteins comprise one or more chains of various amino acids, organised in a specific manner that give the protein a specific structure. When ingested, proteins are broken down into amino acids or short chains of amino acids called peptides. These amino acids play key roles in important metabolic pathways associated with maintenance, growth, reproduction, and immunity.

Amino acids can be classified as either essential or non-essential. Essential amino acids cannot be produced by the animal and must be sourced solely from the diet. Most seaweed species contain all of the essential amino acids and are also rich in some nonessential amino acids such as aspartic and glutamic acid.

In general, the protein content of seaweed ranges from 3-47% and considerable differences exist in the protein content of brown, green and red seaweeds. In contrast to brown seaweeds, red seaweeds contain higher levels of protein which can be up to 47% (Porphyra sp.). Brown seaweeds can have protein levels up to around 20% (Alaria esculenta) whereas the levels found in green seaweeds are as high as 29% (Ulva lactuca). Differences in season, species and environment can have a significant impact on the composition of amino acids and protein in seaweeds.

Bioactive Proteins

Seaweed is a natural source of biologically active proteins, amino acids and peptides. Two groups of bioactive proteins – lectins and phycobiliproteins – are present in some seaweed. Lectins are a group of carbohydrate-binding proteins that display anti-bacterial, anti-cancer, anti-HIV and anti-inflammatory biological activity; lectins have been successfully isolated from a number of seaweeds including Eucheuma sp. and Codium fragile.

Harvesting Seaweed to extract protein

Harvesting Seaweed to extract protein

Another group of proteins – phycobiliproteins – exhibit antioxidant, anti-inflammatory, cholesterol-lowering and antiviral activities to name but a few and have been isolated from the red seaweed, Palmaria palmata. A number of bioactive amino acids are also present in seaweed. One such example is taurine – a bioactive amino acid required for some biological functions. Other bioactive amino acids present in seaweeds include laminine, kainoids, and mycosporinelike amino acids. These amino acids have a wide range of biological properties including antioxidant, hypotensive, insecticidal, anthelmintic, and neuroexcitatory activity. In addition to bioactive amino acids, some bioactive peptides have been isolated from seaweed. These include carnosine and glutathione both of which are antioxidant peptides that protect cells from damage caused by reactive oxygen species. Another bioactive peptide produced by seaweed is Kahalalide F which is a cyclic depsipeptide with anti-cancer activity and is also active in the treatment of AIDS.

Seaweed Protein in Aquafeed

The functional biological properties of seaweed protein make it an excellent candidate for a natural, sustainable alternative to fishmeal in aquaculture. The capacity for large-scale production of seaweeds in Ireland, together with the high-purity seaweed protein extraction developed by Ocean Harvest Technology further enhances the future potential. The availability of such sustainable protein sources is a prerequisite for our ability to continually produce high-quality and safe products.

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Aquaculture Breakthrough in Shrimp Farming

Aquaculture Breakthrough in Shrimp Farming

The black tiger prawn, Penaeus monodon, is a marine crustacean widely reared for food in Asia and is often the one that ends up on your restaurant plate.

Image of a Black Tiger Shrimp on a persons hand

Black Tiger Prawn

At approximately 36 centimetres in length and weighing up to 650 grams this is the world’s largest species of prawn. P. monodon is also the most widely cultured prawn species in the world, although it is gradually losing ground to the whiteleg shrimp, Litopenaeus vannamei. Over 900,000 tonnes are consumed annually, worth about $US 5 billion, two thirds of which is farmed. Frozen head-on, head-off, and peeled shrimp used to be the major export products to the main markets in the USA, EU and Japan. In financial value, Penaeus monodon is the most important traded aquaculture commodity in Asia.

Disease Issues

Being the case with every type of monoculture, major disease problems are always a threat, either from viral Whitespote Disease (WSD) and Yellowhead Disease (YHV) or bacterial Vibrio campbellii .

No chemicals or drugs are yet available to treat such viral infections. Nevertheless, through good management of pond, water and feed, together with close monitoring of the health status of stock inputs, the impact of disease can be greatly reduced.

Outbreaks of the most serious virus disease nearly always occur following dramatic changes in parameters such as water temperature, salinity, dissolved oxygen and water hardness. In some cases, antibiotics and other pharmaceuticals have been used to treat these viruses but their usage comes with a high price and with little success.

Solution

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Ocean Harvest Technology Produce

Oceanfeed™-shrimp is the first marine natural and sustainable functional feed ingredient derived from macroalgae. Unique blending and processing guarantees that all bioactive ingredients are present in the final end product and can replace the  mineral and vitamin premix. A number of reports in the literature have shown some degree of success in improving the clinical outcome of shrimp in viral and bacterial challenges by administering immunostimulants and algal extracts.*

When supplemented to the diet, fucoidan – a seaweed component -partially protected shrimp from White Spot Syndrom Virus (WSSV) infection **. Oceanfeed™- shrimp contains a plethora of natural bioactive compounds which, when incorporated into the diet, can modulate several functions and assist in the control of chronic diseases and viral infections in farmed shrimp. It also allows for diseasefree farmed shrimp to be reared in a more natural and sustainable way, thus easing concerns about environmental impact and sustainability.

Trial Results

OHT recently finalised trials using Penaeus monodon with the objective of researching the effects of Oceanfeed™-shrimp on growth, FCR, and viral and bacterial diseases. Tests were also done to assess the improvement of the clinical outcome of

 shrimp challenged with WSSV and Vibrio after feeding on a diet supplemented with Oceanfeed™-Shrimp. Growth tests were performed by CreveTec- AFT Research Center in biofloc recirculation systems. Challenge tests were performed by the Shrimp Research Group of the University of Ghent in Belgium.

Four different diets (with identical protein and lipid levels) were tested, incorporating 5 and 10% inclusions of Oceanfeed™- Shrimp and two diets with yeast included. Results after the two-month trials showed that inclusion of 10% of Oceanfeed™-shrimp (OF10-shrimp) without the addition of yeast was the best diet of the four tested diets and was able to replace the mineral vitamin premix. Moreover, shrimp fed with 10% inclusion of OF-shrimp were 2.8% heavier than reference shrimp fed with the standard reference diet at the end of the trial. This would translate into a 2.8 tonne increased yield per 100 tonnes of shrimp. The Feed Conversion Ratio (corrected for mortalities) was 0.08 better with 10% inclusion of OF-shrimp. This is 8 tonnes of feed per 100 tonnes of shrimp that would be saved. Mortalities also improved on the OF10 feed by 1.67%. This is 1.67 tonnes shrimp per 100 tonnes. There was a strong effect in the OF10 diet when challenged with Whitespot Viral Disease and the bacterial disease Vibrio with a 40% and 20% lower mortality respectively compared to the control diet.

At the end of the trial, non-challenged shrimp were tasted by a large UK seafood retailer. The trials showed that OF10 shrimp were significantly better in taste and texture than reference diet shrimp.

Global Issues

In 1810 the world population was approximately 1 billion; today, the figure is upwards of 7 billion, and by 2050 it is expected to top 9 billion. Food is therefore going to be incredibly important!

Currently food production is primarily land-based, despite the fact that 71% of the earth’s surface is covered by oceans. That leaves roughly 26% of the earth to support human life, animal life, vegetative life and agricultural production. It is estimated that less than 3% of the earth’s surface is being utilised as arable land. The green revolution has made 3% of the planet incredibly productive. But can it grow? Even more importantly, is it sustainable? The platform (food production) may not be burning, yet, but it is getting quite crowded. What if 10% of the ocean could be used to grow seafood? Shrimp farming will no doubt form a large part of this seafood production.

We are at the cross roads of a blue revolution, and Ocean Harvest Technology has developed feed ingredients from macroalgae to help develop this in a more sustainable way and to lessen the need and dependency on chemicals and additives. A perfect example is the effects of Oceanfeed™-shrimp in shrimp farming.

*(Itami et al., 1998; Takahashi et al., 2000; Chang et al., 2003)

** (Chotigeat et al., 2004)

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Seaweed- Ireland and Abroad

Seaweeds have been used in Ireland for decades for a variety of purposes; however the seaweed industry is still the Cinderella of the aquaculture and seafood Industry. Why is that?

Image of Laminaria hyperborean growing in the intertidal in Ireland

Laminaria hyperborean growing in the intertidal in Ireland

There are diverse market application for seaweeds ranging from food, functional foods and health supplements to agricultural applications, cosmetics, biotechnology and aquaculture. Besides we have over 600 different species of seaweed identified from Irish waters.

Unfortunately seaweeds have never been taken seriously in Ireland compared to fish, mussels, scallops and Oyster and ample funding has gone into developing this resource. The recession of late has made things worse with BIM completely abandoning its seaweed program. Again it is the lack of vision or no vision at all! Countries such as Norway are setting up large scale programmes to develop their seaweed resources and seaweed aquaculture for integrated multi-trophic aquaculture. This is to improve the environmental record of fish farming and progress biofuel development while Norway is a country that has large oil resources.

If we look at seaweed at a global scale it is a different story. Worldwide seaweed aquaculture is a growing sector. Latest figures show a production of over 15 million tonnes wet weight with an economic value of US$ 6.5 billion. The majority of seaweed produced by aquaculture is used for human consumption and for extraction of hydrocolloids although the application for biofuels and other valuable ingredients is starting to play an important role. Moreover, new applications of algae and specific algal compounds in different sectors, such as functional foods, cosmetics, biomedicine and biotechnology are developed. Recent trends in life style towards natural, healthy products are favourable for advancement of seaweed consumption, applications and aquaculture.

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Luckily the private sector in Ireland including Ocean Harvest Technology is rapidly developing the seaweed resources initiating new ideas and implementing their own R&D programs. It is through these initiatives that the future outlook looks good for our forgotten green gold on our shores. Especially the emerging markets such as functional foods and biofuel development from seaweeds will further enhance the sector. Bioethanol is currently produced from land-based crops such as corn and sugar cane, and the continued use of these crops will drive the food versus fuel debate more as demand for ethanol increases. Aquaculture of seaweeds is sustainable, use less or no agricultural inputs (pesticides, fertiliser, land, water), and not be part of the human or animal food chain. Cultivated seaweeds could be used as an alternative biomass source for bioethanol production and production of other high value added chemicals. Seaweed biomass represents an abundant and carbon neutral renewable resource with potential to reduce green-house gas emissions and the man-made impact on climate change. Coupled to fish farming it could even help alleviate environmental issues and recycle nitrates and phosphates.

The recently proposed deep water fish farm at the back of the Aran Islands producing 15,000 tonnes on top of the 13,000 currently produced nationally should incorporate aquaculture of seaweeds. This would allow for improving the environmental record, sustainability and carbon credits of the operation and could form part of the fish feed used for the fish creating the ultimate recycling of nutrients. Now that would be a long term vision!

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Seaweed and the aquaculture Industry; feed it or grow it!

Seaweed and the aquaculture Industry; feed it or grow it!

Anecdotal observations over many years have suggested that seaweeds are an important nutritional resource for terrestrial and aquatic species. Sheep are known to graze regularly on seaweed if they have coastal access. Cod have been observed grazing on seaweed immediately before breeding, while single species of seaweed have demonstrated a significant improvement in disease resistance when included in diets for farmed shrimp. Over the last 10 years the fed aquaculture industry has been bombarded by concerns over environmental impact, animal welfare, sustainability and food safety concerns.

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Seaweeds have been used historically as a feed supplement, but only as single species of seaweed. Benefits from use of seaweed as feed supplements are well documented in many research publications. Different species of seaweed contain many different bioactive molecules. These bioactive ingredients are:

  • Lectins, phycobiliproteins, peptides and functional amino acids such as laminine and hydroxyproline
  • Fucoidan, laminarin, alginic acid, mannitol, carageenan, agars and other short chain oligosaccharides
  • Antioxidants, phenolic compounds and pigments
  • Sterols
  • Fatty Acids
  • Iodine
  • Bromophenols

Scientific evidence of the last decade has shown that these ingredients have antibiotic, antiviral, antimicrobial, mitogenic, anti-inflammatory, anti-adhesion, ACE-inhibitory, antioxidant, anti-cancer and antithrombotic effects with immune-modulation and cytomodulatory effects.

In addition to these ‘bioactive’ molecules seaweeds are a rich source of vitamins and minerals and the right blend of seaweeds can replace most or all of the ‘synthetic’ sources of these ingredients that are used in aquatic and animal feeds.

The Ocean Harvest Technology LogoWith this in mind Ocean Harvest Technology Ltd, an Irish company operating out of Milltown, saw an opportunity and formulated and tested a seaweed-based ingredient, OceanfeedTM that addresses the issues of sustainability and the use of ‘chemical’ ingredients that gives significantly improved performance in growth rate, feed conversion ratio, mortalities, disease and lice resistance and finally flavour and texture of Salmon and shrimp. Many of these synthetic additives such as colorants, antibiotics and preservatives end up in the farmed salmon and have led to recent health scares. An urgent need has arisen for cost-effective alternative and sustainable organic and natural fish feed ingredients and Oceanfeed™ can be part of the solution.

Trial results   

Exhaustive trials were run at the Trial Feed Unit owned and operated by Marine Harvest on the Scottish west coast. The feeds, both reference and test, were manufactured by EWOS (UK) Ltd.  The fish were mixed sex Atlantic Salmon smolts with a starting weight of 145 gms and fish were fed to satiation, light regime followed natural photoperiod and water temperature was ambient. All trials were run in triplicate and the cages were inspected daily. All other physical parameters were measured on a daily basis, and mortalities were recorded on a daily basis. Fish were sampled and assessed against standard farming KPI’s (Key Performance Indicators). Evaluation included growth rate, feed conversion ratio (FCR), condition factor, yield, fat analysis, lice counts, pigmentation, lipid content and profile, flesh flavour and flesh texture. Samples of whole guts were taken for microbiological evaluation and samples of lower intestine were taken (being immediately fixed in buffered formalin) for histological examination. Scottish Quality Cuts (SQC’s) of flesh were taken for lipid analysis, lipid profile, protein analysis and pigment analysis.

IMG_0668

The trial was run for over 1.5 years to go through to complete life cycle from smolt up to 5-7 kg salmon. The following benefits were shown at a 15% inclusion levels of oceanfeed compared with a high grade reference diet:

  1. Higher weight gain
  2. FCR lowered by 0.1 point
  3. Uptake of pigmentation from algae up to 23-24 on SalmoFan.
  4. Higher Omega 3 oil levels in feed
  5. Overall health improvement and faster recovery from Anesthetic
  6. Significant lower sea lice on fish, up to 60% less gravid females and adult stages of male and female lice
  7. 55% lower mortality rates
  8. No deformities or runts
  9. Improved gut health as shown in histological staining of gut sections of trial fish. Caused by short chain Oligosaccharides
  10. Significantly improved taste and texture of fish
  11. Low fat (belly flaps) and leaner fish
  12. Easier to process, fillet and smoke (no oil leakage)
  13. Improved environmental record due to no release of foreign synthetic matters in the feed. Seaweed is a marine product harvested from the marine environment in a sustainable way.

Shrimp trials

The shrimp industry is a factor 10+ larger compared to salmon, with salmon needing about 1.8 million tonnes of feed per annum and shrimp 28 million tonnes of feed. With the results from the salmon trial we could with some adjustments do a similar thing and replace premixes in shrimp feed and improve disease resistance. This shrimp seaweed ingredient called Oceanfeed™- shrimp contains a plethora of natural bioactive compounds which by incorporating in the diet can modulate several functions in shrimp and assist in the control of chronic diseases and viral infections found in farmed shrimp. It allows for disease free farmed shrimp to be reared in a more natural and sustainable way, easing concerns on environmental impact and sustainability. Late last year and early this year several shrimp trials were undertaken using a 10% Oceanfeed diet compared to high standard reference shrimp feed in P. monodon and vannemei, globally the two most cultured shrimp. At the end of the trial part of the shrimps were blast frozen and send for taste testing. After the growth trials OHT commissioned the Shrimp Research unit of the University of Ghent to conduct challenge tests to test for the effect of the inclusion of Oceanfeed on viral and bacterial diseases. The results showed a positive outcome of having Oceanfeed incorporated at 10% in the diet.  In brief the following results were obtained:

  • Higher weight gain (Shrimp fed with Oceanfeed at harvest were 5.2% heavier on average than control)
  • FCR lowered by 0.1 point
  • Uptake of pigmentation from algae in Shrimp.
  • 25% lower mortality rates
  • No deformities or runts
  • Significantly improved taste and texture of the shrimp. Tested and proven with independent taste panels
  • Improved survival and onset of mortality times
  • Improved environmental record due to no release of foreign synthetic matters in the feed. Seaweed is a marine product harvested from the marine environment in a sustainable way.

OceanFeed Shrimp

Growing seaweeds

As most seaweeds that we use for Oceanfeed™ are still from sustainable wild harvest we looked at the possibility of cultivating specific seaweeds of high importance for our feed formulations. Of course seaweed cultivation is nothing new and has been practised for over 300 years in Japan. In Asia, seaweed cultivation is by far more important in terms of output and value than any other form of aquaculture. Looking at a global scale the value of cultivated, managed and wild harvested seaweeds exceed over € 7.0 billion with 89% of this value derived from aquaculture. Seaweeds are also the industrial sources of carrageenans (Chondrus, Eucheuma and Kappaphycus), alginates (Ascophyllum, Laminaria, and Macrocystis) and agars (Gelidium  and Gracilaria). These important polysaccharides are used in the food, textile, paint, biotechnological and biomedical industries and have a global value of approximately € 600 million. Seaweeds have significant value in agriculture as soil additives, fertilizers and seaweed meals with their value over € 20 million. The increasing demand for safe, healthy, and minimally processed foods is creating an opportunity for seaweed products as functional foods, nutraceuticals, and alternative medicinal products. In Ireland, over the last 5 years a strong interest has developed in seaweeds as functional food or nutraceuticals. Research is focused on the establishment of low-volume high-value seaweeds in aquaculture. Moreover, new applications of algae and specific algal compounds in different sectors, such as food supplements, cosmetics, biomedicine and biotechnology are developed. Recent trends in life style towards natural, healthy products are favourable for advancement of seaweed aquaculture in Ireland

Additional environmental benefits

Seaweeds are well-able to reduce N and P in their surrounding environment. If no fertilizers are used seaweed farms could act as N and P filtering units in near coastal environments reducing eutrophication risks from agricultural land run-off .Moreover, seaweed farms can act as short-term CO2 sink reducing acidification of global oceans. Inputs of  biodegradable organic matter and inputs deriving from fertiliser run-off together with run off or dilution from finfish and shellfish rearing in near-shore waters and land based activities have many effects on the quality of coastal inshore waters and are a primary cause of eutrophication due to increased availability of nutrients. Kelp farms (inshore and nearshore) are able to act as bio-filters and are able to remove nitrates and phosphates from the surrounding eutrophic inshore waters. This allows for increased production of farmed seaweed as demonstrated by Chopin et al.,in Canada. Eutrophe waters are high in ammonia and phosphorous which can be stripped from the water by seaweed at rates varying from 60% up to 90% of the nutrient input. Macroalgae are able to take up nitrogen from seawater with rates to allow for a biomass increase of ca. 10% day-1. It is well documented that the green alga Ulva is able to remove 90% of the nitrogenous compounds and the red alga Gracilaria up to 95% of dissolved ammonium from fish effluent. By sea cultivating and harvesting macroalgae as biofilters integrated with other shellfish or fish production systems, nutrient polution from these aquaculture systems could be alleviated through a process called IMTA (Integrated Multitrophic Aquaculture) while increasing production and carrying capacity. Production of macroalgae in near-shore sea cultivation can be harvested for the bioethanol market to produce a value added marketable product acting as both an economic incentive and environmental incentive.

However, the focus has shifted and is more and more fixed on alternative protein resources. Seaweed has levels of crude protein between 15-40% of the dryweight and could be an untapped resource for protein production for fed aquaculture. Analysis of the amino acid profiles of the protein fraction shows very comparable or better profiles compared to fish meal, with the advantage that seaweed protein is about 90% of the extracted product while fishmeal contains about 60-70% protein. By using seaweeds and seaweed proteins it will help reduce the pressure and reliance on wild fish stock and some other traditional ingredients and will soon play an important role in the feed and food production. . Development of future large-scale seaweed farms will positively contribute to the growth of maritime sectors and can be a viable alternative for fisherman as existing infrastructure can be applied. It further might enhance employment opportunities in local rural coastal areas in the form of seed hatcheries, seeding units and processing units and create employment opportunities that otherwise would not exist.

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