Omega 3 oil sources for use in aquaculture Alternatives to the unstainable harvest of wildfish

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1 Omega 3 oil sources for use in aquaculture Alternatives to the unstainable harvest of wildfish Prepared by: Matt Miller, Peter Nichols & Chris Carter

2 Problem Aquaculture is growing Requires wild caught fish Fish stocks/harvest are not increasing Require new sources omega 3 Long chain (C20+) EPA and DHA Fish is not a source of n-3 LC-PUFA as they don t make quantities de novo. Plants and algae are the major sources of n-3 LC-PUFA Aquaculture is a sink not a source of Omega 3

3 GLOBAL FISHERIES CAPTURE VS AQUACULTURE PRODUCTION Million Metric Tons, Fish and Crustaceans Only CAPTURE AQUACULTURE FIG. 1. Global fisheries capture vs. aquaculture production projected. Source: FAO (Food and Agriculture Organization), Bimbo, Inform 2009

4 State of play - Aquafeeds Substitution with vegetable oils/animal fats Soybean, sunflower, canola, palm and linseed n-3 requirement for fish Different n-3 and n-6 levels Oils lack n-3 LC-PUFA Loss of health benefits Seierstad 2005 New marine opportunities Better use (by-catch, waste) Krill 900mt Copepods

5 Other sources of LC omega 3 Biosynthesis Can fish make their own LC omega 3 Precursors to LC omega 3 ALA no effect in humans JT Brenna et all (2009) SDA Microalgae Original source for nearly all omega 3 Genetic modification Modification of renewable sources

6 Biosynthetic precursors

7 Endogenous biosynthesis of omega 3 SDA (18:4 n-3) Biosynthetic hurdle Two fold increase in EPA in TAG when 18:4n-3 fed to rats compared with 18:3n-3 Yamazaki 1991 Conversion in humans James 2003 Salmon cell line: increased EPA Ghioni 1999 Atlantic cod: decrease in EPA and DHA cf. fish oil Bell Biosynthetic Pathway D6 18:3 ALA 18:4 SDA 20:4 20:5 EPA 22:5 Echium plantagineum (Patterson's curse Salvation Jane) High levels of SDA (14%) Hypothesis Canola oil high in ALA (12%) Fish oil high in EPA (19%) and DHA (10%) 22:6 DHA

8 % FA % FA Endogenous biosynthesis of omega Initial Canola Echium Fish 20 Initial Canola Echium Fish ALA SDA EPA DHA 6 week trial in freshwater Miller et al. CBP B Saltwater transfer ALA SDA EPA DHA 12 week trial in salt water Miller et al. J Nutr 2008 Increased gene expression Zeng 2005

9 Microalgae

10 Single-cell oil sources of n-3 LC-PUFA Biodiversity Photosynthetic or heterotrophic organisms Bottom of food chain Source of LC omega 3 Fats, oils, sugars and functional bioactive compounds Genetically and biochemically unique Production Open-culture systems Photobioreactors Fermentation Bio-diesel increasing R&D effort (new production systems)

11 % FA Microalgae in aquaculture Finfish larvae nutrition Thraustochytrid biomass (Algamac) Rotifers (Brachionus spp.) & brine shrimp (Artemia) Biomass feeding trial Salmon trial (Cater et al 2003) Elevated 45 DHA Total LC Omega-3 in Salmon White Muscle Intital Palm Oil Thrausto oil Fish oil Overall increase in w3 Salmon oil feeding trial Other species of fish :5n-3 22:6n-3 Total n-3 Miller MR, Nichols PD, Carter CG (2007). Comp Biochem Physiol A 148 2,

12 Marine Algae Martek World leading supplier of microalgal sources of DHA/EPA Infant nutrition Intellectual property Cost/ Availability Expensive Mass production High production/m 2 Algal photobioreactor: 237g/m 2 $1000/kg Oil yield from Canola : 150g/m 2 $0.75/kg Specialised markets NOT bulk commodity at this stage

13 Future sources of omega 3

14 Genetically modified oil seed crops 18:3 15.0% SDA 18:4 6-des 1.5% 20:4 6-elo 0.8% EPA 20:5 22:5 5-des 5-elo 2.4% 0.1% 5.7% new omega-3 PUFA (Roberts 2005) Arabidopsis DHA 22:6 4-des 0.9%

15 Major LC omega-3 GM players Company/research group Plant Year SDA EPA DHA AA Tobacco Arabidopsis Mustard Canola Soy Arabidopsis Tobacco Cottonseed Tr 0.4

16 Future of Omega 3 in aquaculture Business as usual Economics being the driver Vegetable oils Feeding regimes Biosynthesis (SDA) Limited use/further work Microalgae Too expensive for aquaculture Nutraceuticals/infant formula Technological breakthrough (bio-diesel) Genetic Modification Only viable means (economics, scale) Scientific reality Must go through scientific/social/political scrutiny Reviews (1) Miller, M.R., P.D. Nichols, & C.G. Carter (2008). Nutr. Res. Rev. 21(02): (2) Fish Oil Replacement and Alternative Lipid Sources in Aquaculture Feeds (2010)

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