Environmental performance of blue foods.

Fish and other aquatic foods (blue foods) present an opportunity for more sustainable diets1,2. Yet comprehensive comparison has been limited due to sparse inclusion of blue foods in environmental impact studies3,4 relative to the vast diversity of production5. Here we provide standardized estimates of greenhouse gas, nitrogen, phosphorus, freshwater and land stressors for species groups covering nearly three quarters of global production. We find that across all blue foods, farmed bivalves and seaweeds generate the lowest stressors. Capture fisheries predominantly generate greenhouse gas emissions, with small pelagic fishes generating lower emissions than all fed aquaculture, but flatfish and crustaceans generating the highest. Among farmed finfish and crustaceans, silver and bighead carps have the lowest greenhouse gas, nitrogen and phosphorus emissions, but highest water use, while farmed salmon and trout use the least land and water. Finally, we model intervention scenarios and find improving feed conversion ratios reduces stressors across all fed groups, increasing fish yield reduces land and water use by up to half, and optimizing gears reduces capture fishery emissions by more than half for some groups. Collectively, our analysis identifies high-performing blue foods, highlights opportunities to improve environmental performance, advances data-poor environmental assessments, and informs sustainable diets.

Mediterranean Sea bacteria as a potential source of long-chain polyunsaturated fatty acids.

Long-chain polyunsaturated fatty acids (LC-PUFAs), including EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are important nutritional ingredients in fish feed. So far, fish oil has been used as a main source of LC-PUFAs; however, the limited global supply of fish oil is not able to meet the demand of the growing aquaculture sector. Hence, sustainability of aquaculture industry could be supported by searching alternative sources of these compounds. Marine microorganisms represent a sustainable and stable supply source of LC-PUFAs. A collection of 209 bacterial isolates obtained from sediment samples recovered in the Mediterranean Sea was screened in order to select new LC-PUFAs producers. Among 95 putative producers selected based on colourimetric screening, 31 quickly growing were selected for further studies. The detection of LC-PUFAs was confirmed from 15 isolates belonging to the genera Marinobacter, Halomonas and Thalassospira by GC-FID analysis. Among them, the isolate Marinobacter sp. G16.20 was found to be a potentially high LC-PUFA producer exhibiting relatively high levels of DHA in particular (maximum productivity of 1.85 ± 0.371 mg/g, representing 45.89% of the total fatty acids detected and identified). Microorganisms belonging to the genera reported in this study showed biotechnological traits interesting for their potential future application in aquaculture.

Aquacultural, Nutritional and Therapeutic Biology of Delicious Seeds of Euryale ferox Salisb. : A Minireview.

BACKGROUND: Euryale ferox Salisb. (Makhana) is a rooted macro-hydrophyte, grown as a crop in north Bihar wetlands, India. Makhana refers to yummy pops prepared through mechanical smacking of the baked seeds of E. ferox. New techniques have been evolved to produce pops from seeds at a brisk pace. OBJECTIVE: It is specially associated with marital rituals possibly in view of its spermatogenic properties. It has a high amino acid index but a low glycemic value. The plant carries medicinal values against cardiovascular and diabetes-related diseases. Makhana pops with a high volume to mass ratio, is developed as a reliable system for drug delivery in the recent times. RESULTS: There is a fair prospect of raising multi-faceted industry based on Makhana culture, harvest, post-harvest safety, preparation of pops and various types of food products therefrom and marketing in areas where water-logging is considered as a curse. It may generate employment and strengthen regional economy propping check on population migration primarily due to non-employment and poverty. CONCLUSION: Active research is required to harness this macro-hydrophyte along with co-culture of compatible fish varieties and other hydrophytes into a sustainable livelihood and economic prosperity.

Yeast derived from lignocellulosic biomass as a sustainable feed resource for use in aquaculture.

The global expansion in aquaculture production implies an emerging need of suitable and sustainable protein sources. Currently, the fish feed industry is dependent on high-quality protein sources of marine and plant origin. Yeast derived from processing of low-value and non-food lignocellulosic biomass is a potential sustainable source of protein in fish diets. Following enzymatic hydrolysis, the hexose and pentose sugars of lignocellulosic substrates and supplementary nutrients can be converted into protein-rich yeast biomass by fermentation. Studies have shown that yeasts such as Saccharomyces cerevisiae, Candida utilis and Kluyveromyces marxianus have favourable amino acid composition and excellent properties as protein sources in diets for fish, including carnivorous species such as Atlantic salmon and rainbow trout. Suitable downstream processing of the biomass to disrupt cell walls is required to secure high nutrient digestibility. A number of studies have shown various immunological and health benefits from feeding fish low levels of yeast and yeast-derived cell wall fractions. This review summarises current literature on the potential of yeast from lignocellulosic biomass as an alternative protein source for the aquaculture industry. It is concluded that further research and development within yeast production can be important to secure the future sustainability and economic viability of intensive aquaculture. © 2016 Society of Chemical Industry.

The spread of pathogens through trade in aquatic animals and their products.

It is well known that the transboundary spread of infectious diseases is aided by trade in live animals and the consequences can be severe if, as a result, a pathogen broadens its host range to new species. Trade in aquatic animal species is increasing, and aquaculture is also expanding to meet the growing human population's demands for animal protein. Moreover, it is clear that aquaculture has created potential new pathways by which pathogens and diseases may be introduced or spread to new areas. The risk of pathogen transfer is generally considered greater for the movement of live aquatic animals than for the movement of processed and dead products. The currently available health standards support the concept of minimising the risk of disease and pathogen incursion while, at the same time, avoiding unjustifiable or unnecessary impediments to trade. Nevertheless, the international spread of diseases through the movement of animals still occurs, despite these standards. Consequently, this paper considers the evidence linking international trade in aquatic animals and aquatic animal-derived products with the transmission and spread of diseases. The authors provide examples of pathogen transfer leading to disease spread and considerthe situation of emerging diseases, as well as the need for a holistic approach to deal with risk-based threats at their source.

Fish and its multiple human health effects in times of threat to sustainability and affordability: are there alternatives?

Fish (finfish or shellfish) has been classified as healthy by health professionals despite containing contaminants, since fish is high in long-chain n-3 polyunsaturated fatty acids which have multiple beneficial health effects such as decreased risk of stroke via anti-thrombotic and vasodilative effects, increased heart rate variability, reducing serum triacylglycerol and blood pressure, anti-inflammatory activities, improving visual function, improving attention-deficit conditions/ hyperactivity disorder, schizophrenic and dementia; and may be effective in managing depression in adults. All these beneficial effects are thought to be mediated through altering cell membrane composition, fluidity, receptors and membrane-bound enzymes, gene expression and eicosanoid production. However, natural marine and freshwater fish populations are declining as a result of over-fishing, temperature and climate changes etc. To re-establish and maintain the fish population in China, fishing has been banned for 2-3 months during specified periods of the year, which differs depending on the area, since 1995. The fish population has recovered since implementation of these banned fishing periods, and thereby maintaining the sustainability and affordability of fish. Aquaculture products have had a significant contribution to China's food system, with significant increase in output over the past few decades, from one million tons in 1978 to 32 million tons in 2007. Aquaculture fish represents a higher portion of total aquatic products compared with natural marine and freshwater fish, which has only been achieved in China, and this has contributed greatly to food and health security. China's success in this area is a good model for other developing countries.

Efeito da adiçäo de antioxidantes in vivo na composiçäo em ácidos graxos de filés de pacu (Piaractus mesopotamicus) cultivados / The effect of antioxidants in vivo on fillets fatty acid composition of farmed-raised fresh water fish \"pacu\" (Piaractus mesopotamicus)

O objetivo deste trabalho foi verificar a influência da adiçäo de antioxidantes (tocoferol, BHT e extrato de alecrim Herbalox© in vivo sobre a composiçäo em ácidos graxos de filés de pacu (Piaractus mesopotamicus) cultivados. Os peixes foram cultivados por nove semanas e os ésteres metílicos dos ácidos graxos foram determinados por cromatografia gás-líquido. Os resultados demonstram que os antioxidantes causam diferença na composiçäo em ácidos graxos de filés

Influência da fonte lipídica da dieta e da adiçäo de antioxidantes in vivo na composiçäo em ácidos graxos de filés de pacu (Piaractus mesopotamicus) cultivados / Influence of lipid source of the diet and of the addition of antioxidants in vivo of the composition of fatty acids of farmed-raised freshwater fish \"pacu\" fillets

O objetivo deste trabalho foi verificar a influência dos lipídeos da dieta e da adiçäo de antioxidantes in vivo na composiçäo em ácidos graxos de filés de pacu (Piaractus mesopotamicus) cultivados. Foram utilizados 160 alevinos da fase II de pacu, com peso médio de 212,91g ñ 45,17, divididos em oito grupos experimentais, com 20 peixes por grupo. Estes peixes foram cultivados durante 9 semanas (63 dias), em tanques de alvenaria com fundo de terra, de aproximadamente 50 m², com abastecimento de água contínuo, no Centro de Aquicultura - UNESP, Jaboticabal. Os alevinos receberam dietas isocalóricas e isoprotéicas, sendo que em 4 grupos foi utilizado óleo de soja e em 4 grupos óleo de milho como fonte lipídica...