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.
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Kelp farming is increasing along the temperate coastlines of the Americas and Europe. The economic, ecological, and social frameworks surrounding kelp farming in these new areas are in contrast with the conditions of progenitor kelp farming regions in China, Japan, and Korea. Thus, identifying and addressing the environmental and social impacts of kelp farming in these regions is vital to ensuring the industry’s long-term sustainability. Here, a conceptual model of the human and natural systems supporting this nascent kelp aquaculture sector was developed using Maine, USA as a focal region. Potential negative impacts of kelp aquaculture were identified to be habitat degradation, overfishing of wild seeds, predation and competition with wild fish and genes, and transmission of diseases. Increased food security, improved restoration efforts, greater fisheries productivity, and alternative livelihoods development were determined to be potential positive impacts of kelp aquaculture. Changes in biodiversity and productivity resulting from either negative or positive impacts of kelp aquaculture were confirmed to have downstream effects on local fisheries and coastal communities. Recommendations to improve or protect the ecosystem services tangential to kelp farming include: define ecosystem and management boundaries, assess ecosystem services and environmental carrying capacity, pursue ecologically and socially considerate engineering, and protect the health and genetic diversity of wild kelp beds. Recommendations to ensure that kelp farming improves the well-being of all stakeholders include: increase horizontal expansion, expand and teach Best Management Practices, and develop climate change resiliency. Additionally, an integrated management strategy should be developed for wild and farmed kelp to ensure that kelp aquaculture is developed in the context of other sectors and goals.
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The applications of DNA barcoding have a wide range of uses, such as in taxonomic studies to help elucidate crypticspecies and phylogenetic relationships and analyzing environmental samples for biodiversity monitoring and conserva-tion assessments of species. After obtaining the DNA barcode sequences, sequence similarity-based homology analy-sis is commonly used. This means that the obtained barcode sequences are compared to the DNA barcode referencedatabases. This bioinformatic analysis necessarily implies that the overall quantity and quality of the reference data-bases must be stringently monitored to not have an adverse impact on the accuracy of species identification. With thedevelopment of next-generation sequencing techniques, a noticeably large number of DNA barcode sequences havebeen produced and are stored in online databases, but their degree of validity, accuracy, and reliability have not beenextensively investigated. In this study, we investigated the extent to which the amount and types of erroneous barcodesequences were deposited in publicly accessible databases. Over 4.1 million sequences were investigated in three large-scale DNA barcode databases (NCBI GenBank, Barcode of Life Data System [BOLD], and Protist Ribosomal Referencedatabase [PR2]) for four major DNA barcodes (cytochrome c oxidase subunit 1 [COI], internal transcribed spacer[ITS],ribulose bisphosphate carboxylase large chain[rbcL],and 18S ribosomal RNA [18S rRNA]); approximately 2%of errone-ous barcode sequences were found and their taxonomic distributions were uneven. Consequently, our present findingsprovide compelling evidence of data quality problems along with insufficient and unreliable annotation of taxonomicdata in DNA barcode databases. Therefore, we suggest that if ambiguous taxa are presented during barcoding analysis,further validation with other DNA barcode loci or morphological characters should be mandated.
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Fisheries Economics of the United Statesis produced annually by the National Marine Fisheries Serviceand provides national and state level estimates of the total economic impacts ofU.S.seafood landingsand imported seafood on theU.S.economy.However, it does not contain an estimate of the impact ofU.S.aquaculturally produced seafood. As a demonstrationof the potential for incorporating thisinformation intoFisheries Economics of the United States, we took estimates of production and value forfour aquaculture species: crawfish, salmon, oysters and clams.Using published production cost data andthe same input/output model used forFisheries Economics of the United States,weproduced estimatesof economic impacts.We make recommendations for improving the annual production and valueestimates that are used for the input/output model, and for developingstandardized industry surveyson production costs so that reliable impact estimates can be developed on an annual basis and includedas part ofFisheries Economics of the United States.
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This study aims to quantify the revenue and analyze the value-added seaweed crackers productof SMEs A and SMEs B in Bantaeng District by using the income formula and the value-added revenuemethod. The results shows that SMEs A gains higher revenues amounted IDR 1.618.862 than SMEs B,which get the most revenue IDR. 885.250. It is influenced by the type of product, activities production,capital, and marketing. Meanwhile, the ratio of the value-added of SMEs A was also higher by 91.30%,with a profit rate of 98.54% compared to 88.43% for SMEs B by a margin of 98.43%. It can be assumedthat the seaweed cracker business can improve the incomes and public welfare in Bantaeng.
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The purposes of this paper are to introduce the historical background and price trendsof the imported fishmeal market, and to reveal the pattern of causality between prices in theimported fishmeal market and the market prices of yellowtail and sea bream inlanding areas.Granger causality test was used in this analysis. The results were as follows: 1) there is causality between theprice of imported fish meal andthe market price of sea bream in landing areas, 2) but there isno causality among the marketprices of all combinations without imported fishmeal and sea bream.
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The nutritional value of six tropical seaweeds (Sargassum wightii, Ulva lactuca, Kappaphycus alvarezii, Hypnea musciformis, Acanthophora spicifera and Gracilaria corticata) as complementary source of dietary proteins for human and animal nutrition based on amino acid profile was evaluated. All these species showed similar non-essential amino acid patterns in which aspartic and glutamic acids constituted together a large part of the amino acid fraction (25.2% to 29.5%). Among these, Hypnea musciformis possessed higher amino acid content and better amino acid profile and all of them were generally rich in phenylalanine, tyrosine, threonine and tryptophan and deficient in methionine, cysteine, leucine and lysine. Except U. lactuca all others showed a balanced amino acid profile comparable to FAO reference pattern. Seaweeds being rich in minerals, vitamins, polyunsaturated fatty acids as well as phycocolloids, partial substitution of costly protein sources in animal feeds with seaweed protein may improve feed quality while reducing the cost.
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The potential of seaweeds as alternative protein source was investigated in relation to their amino acid (AA) profiles and the ruminal and total tract digestibility of these AAs. Three red (Mastocarpus stellatus, Palmaria palmata, and Porphyra sp.), four brown (Alaria esculenta, Laminaria digitata, Pelvetia canaliculata, and Saccharina latissima), and two green (Cladophora rupestris. and Ulva sp.) seaweed species were used in this study (hereafter, referred to by Genus name only). All seaweeds were collected in Bodø, Northern Norway, during Spring and Autumn in 2014 and 2015, except Ulva, which was only sampled in Autumn of both years, and Saccharina which was not sampled in Spring 2014. All the samples were studied for AA concentration. Six species (Cladophora, Laminaria, Mastocarpus, Palmaria, Porphyra and Ulva) were selected for the more resource demanding in situ study. Species and season interactively affected the content of total AA in crude protein in different seaweeds investigated (P = 0.02), with values ranging from 67.2 for Laminaria in Spring to 90.2 gAA/16 g N for Ulva in Autumn. in situ AA degradability was also species specific. The seasonality of total AA in crude protein of different seaweed species mostly did not affect their ruminal degradability, except for alanine, while species and season interactively affected proline’s ruminal degradability. The total tract degradability showed that for Laminaria and Mastocarpus, methionine followed by leucine, isoleucine, histidine and lysine, were protected against rumen degradation. These protections seemed to be acid labile allowing digestion in the lower digestive tract. However, due to high indigestible fractions, these two seaweeds provided low amounts of AA to the intestines. Total tract AA digestibility values were the highest for Porphyra (906 g/kg) followed by Palmaria (843 g/kg) and the green seaweeds. To conclude, Laminaria and Mastocarpus are beneficial sources for bypass protein supply as they contain AA protected against rumen degradation. Based on their amount of AA and their AA degradability, Porphyra, followed by Palmaria and the green seaweeds (Ulva and Cladophora) can be considered as relevant sources of protein for ruminants.
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Background: Azoxymethane (AOM) is a potent carcinogenic agent commonly used to induce colon cancer in rats; the cytotoxicity of AOM is considered to mediate oxidative stress. This study investigated the chemopreventive effect of three natural extracts [pomegranate peel extract (PomPE), papaya peel extract (PapPE) and seaweed extract (SE)] against AOM-induced oxidative stress and carcinogenesis in rat colon.
Methods: Eighty Sprague-Dawley rats (aged 4 weeks) were randomly divided into 8 groups (10 rats/group). Control group was fed a basal diet; AOM-treated group was fed a basal diet and received AOM intraperitonial injections for two weeks at a dose of 15 mg/kg bodyweight, whereas the other six groups were received oral supplementation of PomPE, PapPE or SE, in the presence or absence of AOM injection. All animals were continuously fed ad-libitum until aged 16 weeks, then all rats were sacrificed and the colon tissues were examined microscopically for pathological changes and aberrant crypt foci (ACF) development, genotoxicity (induced micronuclei (MN) cells enumeration), and glutathione and lipid peroxidation.
Results: Our results showed that AOM-induced ACF development and pathological changes in the colonic mucosal tissues, increased bone marrow MN cells and oxidative stress (glutathione depletion, lipid peroxidation) in rat colonic cells. The concomitant treatment of AOM with PomPE, PapPE or SE significantly ameliorated the cytotoxic effects of AOM.
Conclusions: The results of this study provide in-vivo evidence that PomPE, PapPE and SE reduced the AOM-induced colon cancer in rats, through their potent anti-oxidant activities.
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The demand for seaweeds has intensified in recentdecades and will most certainly continue to expand. Severalmethods exist to evaluate the biomass of seaweeds in the fieldbut most of them are destructive. The objectives of this studywere (1) to develop and evaluate allometric equations for es-timating seaweed biomass in the field for some harvested spe-cies and (2) to provide uniform calculated dry/wet biomassratios to estimate the relative water content of these seaweeds.Sampling and measurements of more than 350 seaweed indi-viduals were carried out for 8 species of commercial interest.Our models were fitted for both power and linear equationsand were tested for different explanatory variables. While thepower equation was found to be the best for predicting bio-mass of all species, we found that the best descriptive biomet-ric variable varies according to seaweed morphology. Specieswith a bushy morphology were best described by the volume,while long stringy species were best described by the lengthand flat species by the surface. This study attempts to providenondestructive tools that could be used by professional sea-weed harvesters, their employers as well as scientists and pub-lic regulators, to assess the harvest potential of a field of sea-weed in a nondestructive approach.
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