Domestic production of renewable fuels, including algal biofuels, has the potential to meet the dual goals of improving energy security and decreasing greenhouse-gas (GHG) emissions from the transportation sector in the United States. Biofuels produced from microalgae and cyanobacteria offer potential advantages over terrestrial plant-based biofuels, such as high biomass productivity and the ability to grow in cultivation ponds or photobioreactors on nonarable lands using saline water or wastewater sources. However, along with potential environmental and social benefits, production of algal biofuels could result in significant resource inputs and in negative environmental and other detrimental effects, as is true of all forms of energy production.
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IB can play a critical role in maintaining UK competitiveness in global markets and in the creation of a low-carbon knowledge-based economy in the UK. IB is defined as "the use of biological substances" for the processing and production of enzymes, chemicals, materials and energy".
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This report is based on discussions held at a two day workshop held in January 2012, co-organised by the Food Climate Research Network and the Oxford Martin Programme on the Future of Food. The workshop was facilitated by Kath Dalmeny of Sustain and funded by the Foresight Programme and the Oxford Martin Programme on the Future of Food.
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The growing world population demands an increase in sustainable resources for biorefining. The opening of new farm grounds and the cultivation of extractive species, such as marine seaweeds, increases worldwide, aiming to provide renewable biomass for food and non-food applications. The potential for European large-scale open ocean farming of the commercial green seaweed crop Ulva is not yet fully realized. Here we conducted manipulative cultivation experiments in order to investigate the effects of hatchery temperature (10 and 15 °C), nutrient addition (PES and 3xPES) and swarmer density (500 and 10,000 swarmers ml−1) on the biomass yield and biochemical composition (fatty acid, protein, carbohydrate, pigment and phenolic content) of off-shore cultivated Ulva fenestrata in a Swedish seafarm. High seedling densities were optimal for the growth of this northern hemisphere crop strain and significantly increased the mean biomass yield by ~84% compared to low seedling densities. Variations of nutrients or changes in temperature levels during the hatchery phase were not necessary to increase the subsequent growth in an open-water seafarm, however effects of the factors on the thallus habitus (thallus length/width) were observed. We found no significant effect of the environmental factors applied in the hatchery on the total fatty acid or crude protein content in the off-shore cultivated Ulva. However, low seedling density and low temperature increased the total carbohydrate content and furthermore, high temperature in combination with high nutrient levels decreased the pigment content (chlorophyll a, b, carotenoids). Low temperature in combination with high nutrient levels increased the phenolic content. Our study confirms the successful and sustainable potential for large-scale off-shore cultivation of the Scandinavian crop U. fenestrata. We conclude that high seedling density in the hatchery is most important for increasing the total biomass yield of sea-farmed U. fenestrata, and that changing temperature or addition of nutrients overall does not have a large effect on the biochemical composition. To summarize, our study contributes novel insights into the large-scale off-shore cultivation potential of northern hemisphere U. fenestrata and underpins suitable pre-treatments during the hatchery phase of seedlings to facilitate a successful and cost-efficient large-scale rope cultivation.
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Biotechnological production of omega-3 polyunsaturated fatty acids (PUFAs) has become a commercial alternative to fish oil in the past twenty years. Compared to PUFA production by fatty fishes, that from microorganisms has increased due to its promising sustainability and high product safety and to increasing awareness in the expanding vegan market. Although autotrophic production by microalgae seems to be more sustainable in the long term, to date most of the microbial production of omega-3 is carried out under heterotrophic conditions using conventional fermentation technologies. The present review critically analyzes the main reasons for this discrepancy and reports on the recent advances and the most promising approaches for its future development in the context of sustainability and circular economy.
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Seaweeds or macroalgae are attractive candidates for carbon capture, while also supplying a sustainable photosynthetic bioenergy feedstock, thanks to their cultivation potential in offshore marine farms. Seaweed cultivation requires minimal external nutrient requirements and allows for year-round production of biomass. Despite this potential, there remain significant challenges associated with realizing large-scale, sustainable agronomics, as well as in the development of an efficient biomass deconstruction and conversion platform to fuels and products. Recent biotechnology progress in the identification of enzymatic de- construction pathways, tailored to complex polymers in seaweeds, opens up op- portunities for more complete utilization of seaweed biomass components. Effective, scalable, and economically viable conversion processes tailored to seaweed are discussed and gaps are identified for yield and efficiency improvements.
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Anaerobic digester effluent containing high levels of ammonia poses a threat to the environment. To hinder this issue, a modern and promising treatment method incorporates both microalgae and their bioconversion potential. When culturing Chlorella vulgaris at a 1:7 digestate supernatant dilution ratio, biomass concentration was 1.33 g L−1 and 66% of ammonia nitrogen was removed. Furthermore, a prior nitrogen-starved seed method, namely over-compensation strategy, was applied to improve both biomass production and nutrient removal. By using nitrogen-starved seeds after a 48 h nitrogen-free stimulation, biomass yield increased by 1.7-times to 2.56 g L−1. Simultaneously, ammonia nitrogen and total phosphorus removal efficiencies reached 99% and 97% respectively. The enhanced production corresponds to higher chlorophyll fluorescence in the middle and late stages of the culture. In addition, the bioproduct contained 39% carbohydrates, and the proportion of polyunsaturated fatty acids in lipids was 66%. These findings demonstrated that the over-compensation strategy contributed to greater nitrogen removal and high-value bioproduct production in the microalgae-digestate treatment system.
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The main objective of the concept of sustainability is to meet various demands of burgeoning development and fast growing population in the best possible way while considering economic, social and environment aspects. Sustainable sources such as macroalgae or most commonly seaweeds, should be a subject of further investigations. Production of seaweeds is holding the capacity of different conversion roots and applications, such as human food and animal feed, biochemicals, bio-actives, bioremediation, bioenergy and biofuels, due to availability of various trace elements, minerals, vitamins and other biochemical elements, such as proteins, polysaccharides and less lipids with different application opportunities [1]. Seaweeds are widespread around the globe, however, its production is mainly located in Asian region and just a small share is represented by European countries. Not all the countries which have direct access to the sea practice seaweed cultivation or harvesting, including Latvia. Nevertheless, the results of SWOT analysis show that there are considerable amounts of strengths and opportunities for seaweeds to be potential as a feedstock for biorefinery concept in Latvian context, however there are still significant weaknesses and possible threats that are delaying development of the industry. There is non-estimated potential to cultivate seaweeds in Latvian conditions, therefore the overall preliminary analysis on techno-economic feasibility of seaweed biomass cultivation and its conversion system in Latvian context should be done.
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1 IDENTITY
1.1 Nomenclature
1.11 Valid scientific name Laminaria hyporborea (Gunnerus) Foslie. This was described and figured by Gunnerus (1766) as Focus hyperboreus, but recombined as Laminaria herborea by Foslie (1885).
1.12 Nomenclatural synonyms
Many synonyms are given by Foslie (1885), De-Toni (1895), Dii Rietz (1920, 1953) and others, the most important being the following:
Fucus scoparius Strpm, 1762
Fucus digitatus Mohr, 1786
Laminaria digitata Lyngbye, 1819
Laminaria phycodendron la Pylaie, 1824
Hafgygia digitata Kutzing, 1843
Laminaria cloustoni Edmondston, 1845
Hafgygia cloustoni Areschoug, 1883
Laminaria digitata f. typica Foslie 1884
The earlier naine Fucus acoparius of Strom (1762) was invalid because, although it clearly applied only to this species, it was published in a work not generally employing binary nomenclature (Du Riets, 1953).
For many years there was confusion between this species and. L. digitata (HW1S.) Lamour., e.g. by Lyngbye (1819), and Harvey (1846-51) and although Le Jolis (1855) clearly distinguished the two species and listed their reliable characters some confusion continued and even Foslie (1884, 1885) misidentified some specimens (.1iuida, 1965). He (Foslie, 1885) was satisfied, however, that Gunnerus (1766) had not included L. digitata in him description because he examined herbarium including the type specimen, Unfortunately Le Jolis (1855) had not been of -this opinion and thought that Gunnenus' description was thus invalid, and thai Edmondaton' s L, cloustoni was there- fore the first valid name, This synonym was used for many years, particularly in Britain (e.g. Newton, 1931). 1.13 Vernacular naines Norway: Trolitare, sortare, s-tokictare, palmetare, akrame hes-tatare, havtare, kurvtare, stolpetare (Grenager, 1953). British Isles: Tangle, redware, cuvie, cuvy. Germany: Palmentang. B'rance (Brittany): Tall-penn, tali-ebrel.
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Mastocarpus stellatus seaweeds were subjected to different alkali pre-treatments to investigate the effect of alkali type, concentration and treatment duration on the chemical structure and the gelling properties of extracted kappa/iota-hybrid carrageenan (KI). Increasing the concentration in KOH and the pre-treatment time gives KI with lower amounts of nu-carrageenan units, which have a direct impact on the improved gelling properties. However, excessive KOH concentration and pre-treatment duration give KI with smaller molecular mass and depressed gel properties. NaOH is more efficient in converting nu-carrageenan to iota-carrageenan, but no correlation between the chemical structure and gel properties was found. An interaction between the alkali concentration and the pre-treatment duration complicates the rationalization of NaOH efficiency. A set of KI with 60e75 mol% kappa-carrageenan and tailored gelling properties for a wide range of applications is delivered.
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Marine Agronomy Group, CAFNRM, UH-Hilo
200 W. Kawili st., HI 96720, USA
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