marine biotechnology

1. Marine phytoplankton
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A quantum leap for your healthy cells
Dr.Shaleesha A. Stanley

2. What does phytoplankton mean?
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Phyto – light
Plankton – floating
There are 40,000 species of phytoplankton
(PP) available in the sea – mostly naked or
invisible to the human eye
PP makes 50 – 90 % of oxygen that we
breathe
Micro-algae makes the marine forms to live
longer

3. Phytoplankton
Photic Zone
• Can’t move against currents (float or
weakly move)
• >40% of global primary productivity
• Autotrophs
• Form base of ocean food web
• OXYGEN for all life

4. Phytoplankton Classification
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From two
kingdoms
- Monera (bacteria)
– Protista (algae)
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3 divisions (Phyla)
Cyanobacteria
Chrysophyta
Dinophyta

5. Cyanobacteria
Photosynthetic bacteria Use chlorophyll a
 Prokaryotic (No nucleus, few organelles)
 Intertidal, estuaries, coral reefs
 Reproduce by cell fission
 Nitrogen fixation: convert Nitrogen gas
 (N2) to nitrates or ammonia
– Limiting nutrient
 Some symbiotic
– Live in diatoms
– Epiphytes on seagrass
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6. Stromatolites
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Fossils >3 billion years old
•- Amount of O2 in earth's
early atmosphere
•Photosynthesis
byproducts: O2 & calcium
carbonate (lime)
– Build limestone domes
– Vertical growth =
- photosynthesis
•Modern stromatolites: hypersaline lagoons
(too extreme for animal grazers)

7. Division Chrysophyta (2 Classes)
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Most with hardened cell walls or internal skeletons:
silica or calcium carbonate (CaCO3)
•Some have flagella for motility
Chaetoceras
Coccolithophore
Coscinodiscus

8. Chrysophyta species: Dictyocha

9. Size
Most phytoplankton are microscopic –
selective advantage
 Small cells w. higher surface area to volume
ratio

11. Class Chrysophyceae
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Most freshwater
Marine: Coccolithophores & silicoflagellates
Nanoplankton (0-5 μm) = TINY!

12. Coccolithophores
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Calcium CaCO3 plates
– Important microfossils
•Marine only, large #’s at
surface euphotic zone
•Prefer still, nutrient-poor H2O
•Reflect sunlight (albedo): heat & UV light
•Carbon sinks:
– ¯ global
warming

13. Class Bacillariophyceae
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Diatoms
Most abundant phytoplankton
Major oceanic primary producer
Cell walls (frustule) of silica
(glass-like)
Live alone or in chains
Centric or pennate shapes

14. Diatoms
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Asexual reproduction (cell division) rapid
•Occasional sexual repro.
•Ocean surface in areas w/ abundant
nutrients
•Some benthic: reefs, mudflats, rock,
shells

15. Division Dinophyta
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Dinoflagellates
•Most photosynthetic, few heterotrophic
•Unicellular, 2 flagella: adjust vertically in
water column (light, nutrients)
•Cellulose plates
•Rapid asexual cell division, some sexual

16. Dinoflagellates
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Dinoflagellates are Bioluminescent
Organisms produce light by a chemical reaction
•Chemical (luciferin) is oxidized by an enzyme
----produces light
•Luciferin from diet or internal synthesis

17. Red Tides (Dinoflagellate Bloom)
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Mass development of dinoflagellates discolor water
Often caused by excess nutrients
•Enter ocean from land (runoff)
•Fertilizer, sewage

18. Red Tide Impacts:
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•Toxic to marine life: accumulates in clams,
mussels, scallops, fish, mammals
•Death to some species, Human poisoning after
consumption (30 min.)
•Symptoms:
•Paralytic: paralysis, asthma, heart
attack (rare)
•Neurotoxic: tingling, paralysis,
memory loss
•Diarrhetic: cramps, vomiting, diarrhea

19. Nutrient Availability
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•Photosynthesis only provides
carbon,hydrogen, oxygen (C6H12O6)
Also require Calcium, silica,
nitrogen,phosphorus, iron, etc.
•Most dissolved nutrients in cold water near
seafloor (marine snow)
– Below photic zone, isolated by pycnocline
•Upwelling & convection transports cold,
nutrient rich water to surface

20. Phytoplankton abundant in areas of
upwelling & convective mixing of
seawater

21. Phytoplankton rely on bacterial
decomposers to break down organic
matter into usable forms

23. Collecting
plankton