Microalgae have been developed as promising candidates for bioenergy production, coupled with answering challenges related to water pollution and global warming. When combined with wastewater, microalgal biomass production could be freed from a strong dependence on freshwater and chemical nutrients, as well as achieve the additional advantage of wastewater reclamation. However, despite those dual benefits, certain limitations on the growing of algae in wastewater remain to be resolved, including the inevitable presence of bacteria in waste- water, which influences biomass productivity and quality in various ways. Pointing at microalgal-bacterial re- lationships, this study provides an updated review of the application of microalgal-bacterial consortia (MABC) to benefit biomass yield and harvest, and in wastewater remediation, focusing on the main interactions established between the microorganisms integrated within MABC and the factors influencing the behaviours of MABC. The challenges faced by the MABC biotechnology are also discussed, which are primarily rooted in undesirable bacteria that parasitically eat microalgal products and inhibit algal growth through nutrient competition, lysate exudation, or reducing the algal resistance to biotic stress. However, there is a lack of systematic studies on maintaining stable and effective operation of MABCs for wastewater cultivation and high-value bioproduct generation. Knowledge gaps are identified as including systematic information about the responses of MABC to culture conditions and wastewater-borne bacterial communities, and the metabolic mechanisms underpinning the interactions between algae and bacteria in wastewater. Further research focuses and methodologies are proposed in this review, making full use of the advent of omics and computational technology.
Digital library
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The word weed, which carries often a derogative sense, means an economically useless plant (now animal too!) growing wild at the expense or to the detriment of a useful one that is or has been under cultivation. In this sense, the weed is worth only to be weeded out.
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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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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 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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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 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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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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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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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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