Bioactive components in algae
Susan Løvstad Holdt
PhD, Researcher at DTU Environment
Chairman of the Seaweed Network in DK
Annual Plant Biotech Denmark Meeting March 3-4 2011- LIFE-KU
Outline
Basics about algae
Algae of the world- and a world of algae
Algae utilisation
Bioactive components
Algal choice
Algal Biorefinery research
The Seaweed Network in Denmark
Basics
Algae
Algae are a large and diverse group of simple, typically autotrophic
organisms, ranging from unicellular to multicellular forms.
The largest and most complex marine forms are called seaweeds.
They are photosynthetic, like plants, and "simple" because they
lack the many distinct organs found in land plants
Microalgae in fresh and marine water
Different unicellular green algae (from left to right): Chlorella, without flagella; Chlamydomonas,
with flagella, and colonies of 4 cells of Scenedesmus. (Wegeberg og Felby, 2009)
Microalgae production designs
Light, light and….light (CO2 and nutrients)
Flat Panel Airlift Reactor in Stuttgart, Germany (Subitec)
Open-pond Test Facility at Ashkelon (Seambiotic)
Pigments from algae
Astaxanthin – 8000 US$/kg
Haematococcus sp.
Highly antioxidant
http://www.themagicisbac.com/bac-files/haematococcus.jpg
http://algae4oil.com/_borders/clip_image001_000.jpg
http://www.edwardtufte.com/bboard/images/0000c7-699.jpg
Basics
Seaweed / macroalgae
Seaweed is a loose colloquial term encompassing macroscopic,
multicellular, benthic marine algae. The term includes some members
of the red, brown and green algae
Differentiated into:
•Thallus: the algal body
•Lamina/frond: a flattened structure that is somewhat leaf-like
•Sorus: spore cluster
•Holdfast: specialized basal structure providing attachment
•Haptera:finger-like extensions of holdfast anchoring to benthic substrate
Figure 1
Basics
No roots- just holdfasts and haptera
Nutrient uptake takes place at the entire thalli
and there is no need for benthic substrate
Cultivate in suspension or on other substrates
Figure 2. (a) Spores from Palmaria palmata settled on vinylon string (2 mm in diam), (b) spores germinated in 3 weeks in nursery
tanks with added nutrient and aeration and transferred to the field at this stage, (c) harvestable thalli after 4 months of field
cultivation (a-c seeded and cultivated by Maeve Edwards). (d-e) Seeded string with Alaria esculenta coiled around culture rope
and (f) Alaria after approximately 120 days culture at sea (Arbona and Molla 2006).
A world of seaweed
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Figure 3. (a) “Storm toss” Chondrus crispus (Irish moss) harvester from 1975 (Prince Edwards Island, Canada) equipped with waders and basket
to drag through the shallow water at the beach and (b) a typical Irish moss handraker (Pringle and Mathieson 1986). (c) Painting by Carl Locher
(1882), Tangsamlere ved Hornbæk Strand (Seaweed collecters at Hornbæk beach, Denmark). (d) natural harvest of drifting populations of
Furcellaria lumbricalis in Denmark getting loaded on trucks and sold to Litex A/S to extract the “Danish agar” (e) Ascophyllum handraked in Ireland
2008 at low tide and bundled to a metric tonnes “climeen” dragged up shore at high tide (wheel barrow upside down on top of the “climeen”), (f)
where a lorry drives down to the shore at low tide and picks it up (pictures by Maeve Edwards).
A world of seaweed
Cultivation
China knows how!
Polyculture in embayments in Yellow Sea region, China J. FANG
A world of seaweed
Seaweed production in Indonesia;
travelling exhibition: Earth from Above
Boat
Polyculture in embayments in Yellow Sea region, China; Google Earth
A world of seaweed
The commercial seaweed
production worldwide
accounts for 20 % of the
total aquaculture production
Figure 4. Globally harvested (□) and cultivated seaweed
(○) in offshore marine and brackish water from 1950-2006
(FAO 2008).
World production without Asia: 42.000t
Europe
Russian Federation
818 t Phaeophyceae spp (brown seaweed)
France
45 t Asparagopsis spp+Undaria spp (Wakame)
Spain
1 t species unspecified
Figure 5. World seaweed production
(without Asia: 12,600,000 metric tonnes; 99.7%)
in marine and brackish water, 2006
(offshore; metric tonnes wet weight; FAO 2008).
Ireland
Palmaria palmata
(dulse in english,
”søl” in Danish)
Århus
Saccharina latissima
(former Laminaria saccharina)
(”sukkertang” in Danish)
Seaweed utilisation
Gelling purposes
Chondrus crispus (Irish moss)
contains the valuable stabilising
agent carrageenan (E407) used in
a wide range of product such as
toothpaste, gelling agent for marmalade, whipped crème etc.
Soil enrichment
The seaweed can serve as
fertilizer for crops if grounded
into powder or made into
nutrient rich extracts.
Energy: 11,000 MJ/tonnes dried seaweed
Snack, food, feed or
health products
Pleasant taste, minerals and
vitamin and bioactive compounds
are just some of the reasons for
the applications of seaweed in the
kitchen, stall and health products
Reference: Havets dyr og planter
Seaweed utilization
Table 1. Current and potential future uses of seaweeds (free after Indergaard and Jensen 1991).
Extraction
Fermentation
Mechanical
treatment
Pyrolysis
Alginate
Methane
Vegetables/spices
Gas
Agar
Alcohols
Fertilizer supplement
Chemicals
Carrageenan
Esters
Fodder/feed
supplement
Coal
Fine chemicals
Organic acids etc.
Variation and evolution
Variation in content
Holdt and Kraan, 2011
Storage
Cell walls
Laminarin (β -1, 3 glucan)
Alginate, fucans, cellulose
Floridian starch
(amylopectin like glucan)
Agar, carrageenan, xylan,
cellulose
Starch
Mannane, ulvane, xylan,
cellulose
Microalgae composition
High lipid content during stress
Sustainable Energy Ireland, 2009
Microalgal bioactive components
Fatty acids:
EPA, oleic, lineolenic, palmitic, palmmitoleic, and DHA fatty acid
•Reduce risk of certain heart diseases, antioxidant, and
anti-microbial activity
Proteins:
Phycobiliproteins
•Immunomodulation, and anti-cancer activity, hepatoprotective,
anti-inflammatory, and antioxidant properties
Polysaccharides:
Sulfated polysaccharides and insoluble fibers
•Anti-viral, anti-tumor, antihyperlipidemia, and anti-coagulant,
reduce total and LDL cholesterol
Vitamins/tocopherols (vitamin E):
•Antioxidant activity
Phenolic and volatile compounds:
•Antioxidant and anti-microbial activity
Plaza et al, 2009
http://cid-12da36d60f963106.spaces.live.com/blog/
Pigments/Carotenoids: astaxanthin, cantaxanthin, lutein, violaxanthin
•Antioxidant activity, immunomodulation, and cancer prevention
Functional microalgae
Proteins
Vital for growth and development
Beta Carotene
Vitamin-B Complex
Produces Vitamin-A
Which is good for the eyes
GLA
Controls cholesterol
Improve skin tone
For effective metabolism
Of Nutrients
SPIRULINA
Iron
Helps in the formation
Of haemoglobin
Antioxidants
Calcium
Slow down the
Ageing process
For healthy bones
And teeth
Phycocyanin
Strengthens the immune system
Recognized by WHO as one
of the best food supplements
to combat malnutrition
Seaweed composition
Seaweed is known for its high content of polysaccharides,
minerals and certain vitamins
Difficult to conclude on the contents of the different components
as they vary with geography, environment, within populations and season
Proteins: Generally low content:
Green and red:
Palmaria and Porphyra (red):
5-15% of dry weight
10-30%
up to 47%
Lipids: up to 4%, rich in the omega 3-fatty acids
Polysaccharides: 35-60%
Minerals: Na, K, P, Ca, Mg, Fe, I
Vitamins: Vitamin A, B1, B2, B6, B12, C, D og E
Minerals & vitamins
Seaweed contain more minerals than any other food. This is mainly due
to the the surface cell wall polysaccharides that freely and selectively
absorb inorganic nutrients from the sea.
This also include undesirable compounds….. May work as biofilter.
•seaweed contain all the minerals human needs including trace metals
(Murata and Nakazoe 2001)
Seaweed… more than just a fertilizer
Craigie, 2010
Due to the presence of:
Classic growth hormones: auxin, cytokinin, gibberelins etc.
Hormone-like plant growth regulators: Betaines, polyamines,
signal peptides etc.
Cytokinin (isoprenoid and aromatic) and indole 3-acetic acid (IAA)
…etc.
Proteins
10-30 % DW
5-15 % DW
10-47 % DW
Soy beans: 35 %
35% is like soy beans
Seaweed as protein substitute of fish meal (Soler-Vila et al 2009):
~ 10% Porphyra in feed to rainbow trout:
- no changes in growth performance
- enhanced pigmentation
~ 5% Ulva in tilapia fish feed (Sebahattin et al 2009):
- increased growth
- better feed conversion ratio (FCR),
- better protein efficiency ratio (PER)
30% substitution i salmon feed:
- colour
-taste
Contains:
Phycobili proteins: antioxidative effect (Plaza et al 2008)
Lectin: aggregate blood cells (Murata and Nakazoe 2001)
Lipids
Lipids in seaweed can be divided into:
Sterols
Tri-, di- og monoacylglycerols
Phospholipids
Fatty acids:
n-3 Poly Unsaturated Fatty Acids (PUFA)(α–linolenic acid and
eicosapentaenoic acid (EPA))
• other n-3 PUFA such as 18:4n-3, not present in other organisms
→ reduction of
-cardiovascular diseases
-cerebrovascular diseases (Plaza et al 2008)
→ active against
-edema
-inflammatories/erythema
-blood flow (Khan et al 2007)
Rich in sterols, such as fucosterol (especially in brown algae (Fucus))
-possible reduction of blood cholesterol (Plaza et al 2008)
-anti-inflammatory (inhibits infections; Plaza et al 2008)
Pigments
Fucoxanthin: pigment/cartenoid from Fucus species (6%)
• Antioxidant (Le Tutour et al 1998)
• UV-B defence (Heo and Jeon 2008)
• Preventive effect on cerebrovascular diseases
(change in brain blood flow; Plaza et al 2008)
• Increased metabolisme (Plaza et al 2008)
•Anti-obesity
•Possible up-regulation of UCP1 in BAT (brown adipose tissue)
•2% lipids from Undaria reduce White AT (g/kg body weight)
of mice and rats (Maeda et al 2008)
Holdt and Kraan, 2011
Polysaccharides
Holdt, 2009
Other…
Phenols mainly in brown algae
located in the outer membrane in physode-vesicles
Porphyra: (shinorine and pophyra-334 phenol)
Sargassum: 2-3% og 6%
Ascophyllum: 4-13% og 5 %
Fucus: 2%
Laminaria: 0.2% and 0.2-2.6%
Antioxidant og anti-Staphylococcus effekt (Zubia et al 2008)
Other effects of phlorotannin:
antiherbivour (#1, #111)
may form complexes with alginic acid
they may even be excreted to the surrounding media
antioxidant (in vitro #8, ESR cellul no cytotoxicity on human fetal lung fib
antidiabetes (ref in #8)
radiation protection (ref in #8)
anti-cancer (ref in #8)
anti-HIV (ref in #8)
anti-allergic (ref in #8)
anti-plasmin inhibition (#10)
photochemoprevention (#10)
antiproliferative activities (#18)
Halogenated compounds, highly active
halogenated furanones
kahalalide F
furanones
antifouling (Delsea pulcra)(#70)
treatment of lung cancer, tumors and AIDS (Bryopsis)(#70)
anti-fouling (#147, #148)
Associated bacterial communities
antifouling invertebrate larvae (#106, #107, #152-154)
antifouling, bacteria (#143 and #152)
antifouling, fungus (#152)
anti-pathogenic (#107)
antifouling, micro- and macroalgae (#153)
Seaweed extracts
anti-fungicidal (ref in #30 and #69)
anti-ulcerative activity (ref in #30)
anti-oxidation (#67)
anti-bacterial (#69, #125, #127 and #165)
anti-fouling (#157, #164)
anti-pathogenic bacterial (#167 and #170)
Anti-inflammatory (#61)
Undaria / Wakame in pasta
•Antioxidant properties, due to the content of phenols,
lipid composition and fucoxanthins analysed
•10 % addition did not change the fllavour of the pasta
•n-3:n6 fatty acids relationship vas 1:3 in the seaweed pasta and
1:15 in the normal pasta
•Heat from cooking did not destroy the fucoxanthin
(Prabhasankar et al 2009)
Undaria in synergy with fish oils in rats
•Analysed the lipid concentration in liver and serum and
the enzymatic activity involved in the fatty acid
metabolism of the liver
•Reduced concentration of tricylglyceroles in serum and liver
•Seaweed(19%), fish oil (4%) or seaweed and fish oil in diet
•Greatest reduction was with diet of both seaweed and fish oil
•Also a synergetic effect between seaweed and fish oil in
the enzymatic activity
(Murata et al 2001)
Algal Biorefinery
High rate algal biomass production for food, feed,
biochemicals and biofuels
Algal Biorefinery
Selection of suitable Algal species
Algal cultivation optimisation
Production of food supplements from algal biomass
(alginates, β-carotene, omega-3 fatty acids)
Production of biochemicals
(antioxidants, pigments, phenolic compounds)
Biofertilizer
Biofuels production (biohydrogen, biogas, bioethanol)
Technological, societal, environmental and economical
assessment of sustainability
Demonstration
Cultivation
Marin Centre of the Great Belt (MKS)
Funded by: Slagelse local authority and LAG Ministry of Food
Partners: Slagelse, GEMBA Seafood Consulting, Bisserup Fisk,
DTU Food, Fishermen at Omø
Commercial utilization of organic seaweed for consumption
DFFE: Bælternes Fiskeriforening, GEMBA, DTU
The Danish Shellfish Centre in Limfjorden
New species- including seaweed
Fornyelsesfonden: DSC, DMU, DTU Environment etc.
Criteria for species selection in DK
High in added value products
High growth rate/yield
Low cultivation costs/manpower
Sustainable Energy Ireland, 2009
-Soil enrichment and energy potential are low in priority,
however possible in the waste of all species
Algal choice depends on end-product(s)
Micro
Macro
Low (4-60 %)
High (15 to 75 %)
High (up to 40 %)
Low (max 4 %)
Proteins
Similar (6-60 %)
Similar (5-50 %)
Pigments
Similar/but
different types
Similar/but
different types
Similar (up to 16
%)
Similar (up to 14
% in brown sp.)
Polysaccharides
Lipids
Phenolics
(flavonoids)
fish feed (omega-3 and protein)
Pigments
Phenolics/flavonoids/phlorotannins
alginate
Macro and microalgal cultivation
Landbased (tanks) and
bioreactors
• Controlled
–
–
–
–
•
•
•
•
light
nutrients
flow
fouling
Safe
Harvest!
Expensive (energy, nutrients)
Maintenance (man power)
Off-shore (lines/floating)
• No control on growth
parameters
• Higher risk
• Cheaper
• No use of agricultural
land
Recommendations by the Seaweed Network in DK
Steering committee
White paper for aimed at guiding decision makers within
research grants, business, local authorities and
national politicians in Denmark
Some important point:
Biomass or research within utilization first?
Logistics no problem: follow the fish!
Production including breeding (we need the biomass)
Enzyme development for pretreatment in order to utilize the biomass
Clear guidelines of legislation in regard to non or “novel food”
according to EU and daily intake recommendations
Feed ingredient potential (organic feed)
Thank you!
The Seaweed Network in DK
[email protected]
www.akvakultur.dk (”tangnettet)
Information in Danish
Why eat seaweed?
Taste good: Different taste and also used
as flavour enhancer
Healthy: Low in calories, loow in fat,
high in sugars (but dietary fibres),
antioxidants
High content of vitamins
and minerals
Health effects (scientifically): anti-cancer, anti-virus,
lower the risk of cardiovascular diseases etc.
Easy: Dried and long shelf-life. Collect yourself
Beautyful: Sprinkle as decoration or build in….