Development of guidelines for using bioextraction technologies to manage nutrients in New Hampshire\u27s estuarine waters

There is growing literature on bioextraction approaches to managing nutrients in coastal waters, and it includes studies using a variety of species. Bivalve mollusks and macroalgae have received the most attention for several reasons, but perhaps foremost because of their aquaculture potential. A December 2009 workshop at the University of Connecticut, which included speakers from several countries, indicated overall that although bioextraction approaches hold substantial potential there are still many unanswered questions. The present review takes a “what we know/what we need to know” perspective, and focuses on aquaculture. For some taxa (e.g., eastern oyster), wild populations occur in New Hampshire which provide substantial nutrient bioextraction. The associated processes that result in nutrient removal from the ecosystem, however, are generally more complicated and much more difficult to unambiguously quantify except when actual harvest data are available. Therefore, the present review focuses on aquaculture, and it is restricted to those taxa (plants and animals) that occur in New Hampshire. It should be noted that the present project is associated with a recently completed project (funded by the Piscataqua Region Estuaries Partnership [PREP]) consisting of a field experiment designed to provide empirical data on nutrient uptake by oysters. The final report for this project represents the starting point for future research that will more completely characterize the bioextraction potential for oysters in New Hampshire (see discussion of Grizzle and Ward 2011 below)

Experimental Quantification of Nutrient Bioextracti on Potential of Oysters in Estuarine Waters of New Hampshire

This project was a short-term field experiment conducted in summer 2010 and designed to provide preliminary data on the bioextraction (removal) of carbon (C) and nitrogen (N) for two different size classes (both \u3c76mm shell height) of eastern oysters (Crassostrea virginica) at six sites in the Great Bay estuarine system in New Hampshire. Sites were chosen to represent a range of ambient nutrient concentrations, water flow conditions, and location within the estuary. Two of the sites were at oyster aquaculture farms: Granite State Shellfish at the mouth of the Oyster River, and Little Bay Oyster Company near Fox Point in Little Bay. At each site, oysters were deployed in 10mm mesh polyethylene bags typically used on oyster farms in New England. Approximately one thousand “seed” size (10?15 mm shell height), or two hundred (200) 1?year old (30?40 mm shell height) oysters were placed into each bag. Two bags (one for each size class) were suspended 10?20 cm off the bottom attached to plastic coated wire cages at each site from August 9 until November 4, 2010. The oysters were inspected and the bags were cleaned each month to reduce fouling. There were no significant differences in final size among the six sites, indicating similar growth rates. Soft tissue %C and %N values, however, varied substantially and significantly (ANOVA, P\u3c0.05) among the sites. Tukey tests indicated significantly higher %C and %N at the Squamscott River (SQ) site, and significantly lower at the Little Bay Oyster (LBO) farm site, compared to the other sites. The ranges of mean soft tissue %C and %N were, respectively, 26.9 to 47.2 and 4.7 to 10.6. Because shell material was not analyzed in the present study, literature values for shell were combined with soft tissue data from the present study to arrive at total whole animal C and N content. Oysters with mean shell height of 35.7 mm contained 0.6 g of C and 0.01 g of N; oysters with mean shell height of 55.6 mm contained 3.1 g of C and 0.07 g of N. Preliminary calculations indicated that if 20 0 acres of bottom area were in full farm production, the annual N removal from the estuary from oyster harvest alone would be 12.56 tons. It is emphasized that the present study represents only the first step in characterizing the nutrient (focusing on N) bioextraction potential for oyster farming in New Hampshire

The Potential of Seaweeds as a Source of Functional Ingredients of Prebiotic and Antioxidant Value

Two thirds of the world is covered by oceans, whose upper layer is inhabited by algae. This means that there is a large extension to obtain these photoautotrophic organisms. Algae have undergone a boom in recent years, with consequent discoveries and advances in this field. Algae are not only of high ecological value but also of great economic importance. Possible applications of algae are very diverse and include anti-biofilm activity, production of biofuels, bioremediation, as fertilizer, as fish feed, as food or food ingredients, in pharmacology (since they show antioxidant or contraceptive activities), in cosmeceutical formulation, and in such other applications as filters or for obtaining minerals. In this context, algae as food can be of help to maintain or even improve human health, and there is a growing interest in new products called functional foods, which can promote such a healthy state. Therefore, in this search, one of the main areas of research is the extraction and characterization of new natural ingredients with biological activity (e.g., prebiotic and antioxidant) that can contribute to consumers? well-being. The present review shows the results of a bibliographic survey on the chemical composition of macroalgae, together with a critical discussion about their potential as natural sources of new functional ingredients.Fil: Gomez Zavaglia, Andrea. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Prieto Lage, Miguel Ángel. Universidad de Vigo; EspañaFil: Jiménez López, Cecilia. Universidad de Vigo.; EspañaFil: Mejuto, Juan Carlos. Universidad de Vigo. Facultad de Ciencias de Ourense; EspañaFil: Simal Gándara, Jesús. Universidad de Vigo; Españ

Microbiologically influenced corrosion: looking to the future

This review discusses the state-of-the-art of research into biocorrosion and the biofouling of metals and alloys of industrial usage. The key concepts needed to understand the main effects of microorganisms on metal decay, and current trends in monitoring and control strategies to mitigate the deleterious effects of biocorrosion and biofouling are also described. Several relevant cases of biocorrosion studied by our research group are provided as examples: (i) biocorrosion of aluminum and its alloys by fungal contaminants of jet fuels; (ii) sulfate-reducing bacteria (SRB)- induced corrosion of steel; (iii) biocorrosion and biofouling interactions in the marine environment; (iv) monitoring strategies for assessing biocorrosion in industrial water systems; (v) microbial inhibition of corrosion; (vi) use and limitations of electrochemical techniques for evaluating biocorrosion effects. Future prospects in the field are described with respect to the potential of innovative techniques in microscopy (environmental scanning electron microscopy, confocal scanning laser microscopy, atomic force microscopy), new spectroscopic techniques for the study of corrosion products and biofilms (energy dispersion X-ray analysis, X-ray photoelectron spectroscopy, electron microprobe analysis) and electrochemistry (electrochemical impedance spectroscopy, electrochemical noise analysis). [Int Microbiol 2005; 8(3):169-180