Pectic Oligosaccharides and Other Emerging Prebiotics

A prebiotic is a selectively fermented ingredient that results in specific changes in the composition and/or activity of the gastrointestinal microbiota, thus conferring benefit(s) upon host health. The most widely accepted prebiotics are lactulose, inulin, fructooligosaccharides (FOS), galactooligosaccharides (GOS), and the human milk oligosaccharides (HMO). However, there is a growing list of potential prebiotics although the evidence for these, especially in humans, is not as well established as for FOS and GOS. Some of them are already commercialized but others such as polydextrose (PDX), pectic oligosaccharides (POS), bacterial exopolysaccharides (EPS), polysaccharides derived from algae and sugar alcohols are still in the early stages of development. This chapter summarizes the scientific literature regarding the manufacture and the evaluation of the properties of this group “emerging prebiotics”

Aquaculture Production of the Brown Seaweeds Laminaria digitata and Macrocystis pyrifera: Applications in Food and Pharmaceuticals

peer reviewedSeaweeds have a long history of use as food, as flavouring agents, and find use in traditional folk medicine. Seaweed products range from food, feed, and dietary supplements to pharmaceuticals, and from bioenergy intermediates to materials. At present, 98% of the seaweed required by the seaweed industry is provided by five genera and only ten species. The two brown kelp seaweeds Laminaria digitata, a native Irish species, and Macrocystis pyrifera, a native New Zealand species, are not included in these eleven species, although they have been used as dietary supplements and as animal and fish feed. The properties associated with the polysaccharides and proteins from these two species have resulted in increased interest in them, enabling their use as functional foods. Improvements and optimisations in aquaculture methods and bioproduct extractions are essential to realise the commercial potential of these seaweeds. Recent advances in optimising these processes are outlined in this review, as well as potential future applications of L. digitata and, to a greater extent, M. pyrifera which, to date, has been predominately only wild-harvested. These include bio-refinery processing to produce ingredients for nutricosmetics, functional foods, cosmeceuticals, and bioplastics. Areas that currently limit the commercial potential of these two species are highlightedHorizon 202

Marine Polysaccharides Volume 1

The field of marine polysaccharides is constantly evolving, due to progress in the discovery and production of new marine polysaccharides. Seaweed remains the most abundant source of polysaccharides, but recent advances in biotechnology have allowed the production of large quantities of polysaccharides from a variety of micro-algae, by controlling growth conditions and tailoring the production of bioactive compounds in a bioreactor. Of particular interest are polysaccharides produced by micro-organisms from extreme marine environments, due to their recognized different biochemistry. Extracellular polysaccharides (EPSs) with unique properties produced by a number of micro-algae are known. The first volume is a collection of papers concerning the identification and characterization of novel marine polysaccharides. It is divided into three chapters; the first two are dedicated to polysaccharides from different marine sources (algae, micro-algae, animals), while the third one gathers information on the isolation, characterization and bioactivity of new EPSs

Nutramara - Marine Functional Foods Research Initiative (MFFRI/07/01)

Final report of projectThe NutraMara – Marine Functional Foods Research Initiative was conceived by Sea Change - A Marine Knowledge, Research and Innovation Strategy for Ireland 2007-2013. The goal was to develop a collaborative funding mechanism that would create new research capacity and build the capabilities required to maximise the potential of Ireland’s extensive marine bioresources. By supporting a strong interdisciplinary research team, capable of exploring marine animals and plants as a sustainable source of materials for use as functional ingredients and foods, the vision for NutraMara was to position Ireland to the fore in use of marine bioresources as health beneficial ingredients. Commencing in 2008 and supported by funds of €5.2 million from the Marine Institute and the Department of Agriculture, Food and the Marine, the research programme was led by Teagasc as the head of a multi-institutional consortium. The NutraMara consortium comprises marine bioresources and bioscience expertise, with food science and technology expertise from University College Cork; University College Dublin; the National University of Ireland Galway; the University of Limerick and Ulster University. Research effort was directed towards exploring Ireland’s marine bioresources – including macro- and microalgae, finfish and shellfish from wild and cultured sources: and discards from processing fish as sources of novel ingredients with bioactive characteristics. This discovery activity involved the collection of over 600 samples from 39 species of algae and fish and the analysis of 5,800 extracts, which resulted in 3,000 positive “hits” for bioactivity. The NutraMara consortium has built a strong research capacity to identify, characterise and evaluate marine-origin bioactives for use as/in functional foods. It further built the capacity to develop model foods enhanced with these marine-origin functional ingredients; providing insights to the processing challenges associated with producing functional ingredients from marine organisms. The consortium was actively engaged in research activities designed to identify and assess bioactive compounds from available marine resources, including polyphenols, proteins/peptides, amino acids, polysaccharides, polyunsaturated fatty acids and materials with antioxidant, probiotic or prebiotic properties. A key component of NutraMara’s activities was the development of human capital. The recruitment of M.Sc. and PhD students and their integration within a dynamic research environment that has strong links to industry, provided lasting expertise and capabilities, which are relevant to the needs of Ireland’s food and marine sectors. NutraMara research led to the awarding of eighteen PhDs and recruitment of 21 post-doctoral researchers over the eight year research programme. In excess of 80 peer reviewed publications resulted from this research and more publications are planned. A further 100 posters and conference presentations were also delivered by NutraMara researchers and Principal Investigators. The development and implementation of training and exchange programmes aimed at providing early stage researchers with inter-disciplinary skills that are critical to their development as researchers, enhanced the research capacity of institutions, the industry sectors and the country as a whole. Principal Investigators involved in leading the NutraMara research programme have secured additional research grants of almost €6 million from national and international sources and are engaged in extensive research collaboration involving marine and food research expertise; an activity which did not exist prior to NutraMara. The dissemination of knowledge and transfer of research results to industry were key activities in the research programme. The research outputs and visibility of NutraMara activity nationally resulted in 10 companies engaging in research and development activity with the consortium. Regular workshops and conferences organised by NutraMara attracted close to five hundred participants from Ireland and overseas. Members of the NutraMara core PI group have contributed to the formulation of new national foods and marine research policy and national research agenda, both during the national prioritisation exercise and in sectoral research strategies. This final project report describes the process by which research targets were identified, and the results of extensive screening and evaluation of compounds extracted from marine bioresources. It also highlights the development of new protocols designed to extract compounds in ways that are food friendly. Evaluating the functional properties, bioactivity and bioavailability of high potential marine compounds involved in vitro and in vivo testing. Pilot animal and human intervention studies yielded further insight to the potential and challenges in developing marine functional ingredients. As a result of work completed within the NutraMara consortium, Ireland is well positioned to continue to contribute to the development of ingredients derived from marine organisms and in doing so support the on-going development of Ireland’s food sector.Marine Institut

Marine Functional Foods Research Initiative (NutraMara)

Sea Change—A Marine Knowledge, Research & Innovation Strategy for Ireland 2007-2013—was launched in early 2007 and was the outcome of extensive analysis and consultation with government departments, state agencies, industry and the third-level sector. It outlines a vision for the development of Ireland’s marine sector and sets clear objectives aimed at achieving this vision, namely to: 1. Assist existing, and largely indigenous, marine sub-sectors to improve their overall competitiveness and engage in activity that adds value to their outputs by utilising knowledge and technology arising from research. 2. Build new research capacity and capability and utilise fundamental knowledge and technology to create new marine-related commercial opportunities and companies. 3. Inform public policy, governance and regulation by applying the knowledge derived from marine research and monitoring. 4. Increase the marine sector’s competitiveness and stimulate the commercialisation of the marine resource in a manner that ensures its sustainability and protects marine biodiversity and ecosystems. 5. Strengthen the economic, social and cultural base of marine dependant regional/rural communities. The Sea Change strategy was developed as an integral part of the government’s Strategy for Science, Technology and Innovation (SSTI) and the Marine Institute as the lead implementation agency is working within SSTI policy and with government departments and agencies to deliver on the Strategy. The Marine Institute managed Marine Research Sub-Programme, one of eight sub-programmes within the Science, Technology and Innovation (STI) Programme of the National Development Plan 2007—2013, targets funding to meet the objectives of the Sea Change strategy. Over the lifetime of Sea Change, funding will be provided for: • Project-Based Awards o Strategic Research Projects o Applied Research Projects o Demonstration Projects o Desk/Feasibility Studies • Researcher Awards o Strategic Research Appointments o Research Capacity/Competency Building o Post-Doctoral Fellowships o PhD Scholarships • Industry-Led Research Awards o Company Awards o Collaborative Awards • Infrastructure Awards o Infrastructure Acquisition o Access to InfrastructurNutraMara – Marine Functional Foods Research Initiative: The goal was to create new research capacity and build the capabilities required to maximise the potential of Ireland’s extensive marine bioresources. By supporting a strong interdisciplinary research team, capable of exploring marine animals and plants as a sustainable source of materials for use as functional ingredients and foods, the vision for NutraMara was to position Ireland to the fore in use of marine bioresources as health beneficial ingredients.Lead Partner: Teagasc – The Irish Food and Agriculture Authority Project Partners: National University of Ireland Galway University College Dublin University of Limerick Ulster University University College Cor

Enhancing biomethane production from anaerobic digestion of Sargassum muticum

Higher methane yields from the anaerobic digestion (AD) of Sargassum muticum could improve the process energy balance and make its use during AD more economical and energetically favourable. Previous research showed that after 28 days of AD, methane yields from S. muticum were low (17% of the theoretical yield). This thesis aims to identify the causes of the low methane yield. Biochemical methane potential tests of freshly harvested, rinsed, and freeze-dried (FD) spring and summer S. muticum sampled over three years delivered yields of 27–39% and 24–32% of the theoretical, respectively. FD samples were extracted with water or with 70% (v/v) aqueous methanol (MeOH); methane yields per gram volatile solids of the extracted samples were higher than the untreated FD samples by up to 19.1% and 26.6%, respectively. Proximate, ultimate, and biochemical analyses showed that untreated FD biomass contained ash contents of 24.2–28.1% dry weight, with total dietary fibre representing 49.8– 67.4% of the organic fraction. Water- or MeOH-extracted spring and summer biomass were higher in total dietary fibre content (75.3–82.8% of the organic fraction) and lower in soluble dietary fibre (SDF) and phenolic content than the FD samples. Indices calculated for bioconversion of the biomass to methane were negatively correlated with the SDF and phenolic contents. Water-extracted spring biomass had lower SDF content than the FD and water- extracted summer samples and produced higher methane yields. The aqueous MeOH extract of S. muticum was examined after repeated extraction (×9) with 1% polyvinylpolypyrrolidone (PVPP). The PVPP-treated extract was 93.7% lower in phenolic content (Folin-Ciocalteu assay) and 24.4% higher in protein content than the untreated extract, with no significant difference in the lipid contents. MeOH-extracted biomass combined with the PVPP-treated extract produced 85.7% higher methane yields than when combined with untreated MeOH extracts. Membrane filtration of the untreated MeOH extract yielded a high molecular weight (MW) (≥ 5 kDa) fraction, which contained 90.7% of the total phenolic content of the extract. It inhibited methane yields by 41.9% when combined with MeOH-extracted biomass; however, since the methane yields of the extracted biomass remained low (≤ 32% of the theoretical, an increase from ≤ 27%), recalcitrance of the total dietary fibre also represents a limiting factor. Improving methane conversion of the residual fibre fraction after phenolics’ extraction is required to utilise this biomass in a biorefinery approach efficiently

Effect of Algal-Derived Compounds on Growth and Survival of The Fish Pathogen Francisella noatunensis subsp. orientalis

Piscine francisellosis, caused by Francisella noatuenensis subsp orientalis (Fno), is an emerging infectious disease in the tilapia industry, but no effective commercial treatments or vaccines are available. The use of immunostimulants is a promising method to control diseases in aquaculture, and various algae and algal-derived compounds are potent immunostimulants for improving immune status. Algae produce a great variety of secondary metabolites that exert a broad spectrum of biological activities. The aim of this thesis was to evaluate the effectiveness of algal compounds against Fno in vitro and in vivo and determine their potential to control francisellosis infection in Nile tilapia Oreochromis niloticus L. under experimental conditions, and in an alternative host, namely the greater wax moth Galeria mellonella. Some of the algae and their compounds (Chlorella sp., alginic acid, and ß-glucan) exerted antimicrobial activity in vitro against Fno, Aeromonas hydrophila and Streptococcus agalactiae and stimulated responses of Nile tilapia macrophages (Chapter 2). An immersion challenge model for Fno STIR-GUS-F2f7 was developed in two genetic groups of Nile tilapia, and the homo gold strain was more susceptible to infection than wild type (Chapter 3). In vivo trials were conducted in Nile tilapia homo gold where fish were fed diets supplemented with 10% Scenedesmus quaricauda, 10% Haematococcus pluvialis, and 0.1% or 0.2% alginic acid or ß-glucan, and then challenged with Fno and co-infected with S. agalactiae (Chapter 4). The Fno challenge failed to produce mortality; however, co-infection resulted in high mortalities in all groups. As the in vivo trial in tilapia could not be to repeated, a G. mellonella model for Fno was validated. Fno doses between 0.7–1.7 x 108 CFU mL-1 killed G. mellonella, while tetracycline, alginic acid and ß-glucan rescued the wax moth from lethal doses of bacteria (Chapter 5)