A short intro to seaweeds and their relationship to people (history, uses) for a public workshop in Tofino, B.C. in 2014 for Raincoast Education Society
Public, interactive talk about the biodiversity of seaweeds in the ocean for the Beaty Biodiversity Museum at the University of British Columbia, Canada. Lots of beautiful underwater pictures.
Public, interactive talk about the biodiversity of seaweeds in the ocean for the Beaty Biodiversity Museum at the University of British Columbia, Canada. Lots of beautiful underwater pictures.
A presentation that discusses the ecological, ethical and health costs of consuming shark fin soup. While this presentation was designed for high school students in British Columbia, Canada, it can be modified to suit other age groups and other regions. However, there are some graphic images that may not be suitable for younger audiences.
Predator-prey relations refer to the interactions between two species where one species is the hunted food source for the other. The organism that feeds is called the predator and the organism that is fed upon is the prey.
A presentation that discusses the ecological, ethical and health costs of consuming shark fin soup. While this presentation was designed for high school students in British Columbia, Canada, it can be modified to suit other age groups and other regions. However, there are some graphic images that may not be suitable for younger audiences.
Predator-prey relations refer to the interactions between two species where one species is the hunted food source for the other. The organism that feeds is called the predator and the organism that is fed upon is the prey.
lobsters and crab fisheries in INDIA is a vast and enormous amount of catch and exports are being made.
this slide describes about the methods, distribution, annual landings and important species of lobster and crabs in India.
We know the Rotary Club of Sylva is the Greatest Rotary Club in the World and today we learned why theTuckaseigee Chapter #373 of Trout Unlimited is the Greatest Trout Unlimited chapter in the World! Thank you to Shannon Messer and the TU members for all they do to make sure we will live in the NC Trout Capital for many future generations. Shannon made a great presentation to our club today and is pictured with Club President Margaret.
This presentation introduces ancient Hawaiian fishing and compares it to modern-day fishing. This project allows its viewers to see how an indigenous culture lived off of the ocean.
Saving our not so Furry Friends - Long live the freshwater crocodile by Anton...Art4Agriculture
This is the story of how Antonia found herself in the middle of nowhere wrestling crocs on a study with PhD student Ruchira Somaweera.
An experience that left her with more than an award winning thong tan on arrival back home to a little town called Sydney
Oysters are experiencing a renaissance in the United States as a new dining trend. This guide provides some basic information about oysters including their biology, their growth methods, and their industry.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
8. Monte Verde, Chile Images:
http://www.pasthorizonspr.com/index.php/archives/10/2011/t
9. Japan and Nori
• harvested since 6th century
• for many centuries, nori fishers
simply gathered what could find
at low tide.
• cultivated since 16th century
Utagawa Hiroshige’s “One hundred famous
views of Edo”, #109 (1857)
10. Japan and Nori
• harvested since 6th century
• for many centuries, nori fishers
simply gathered what could find
at low tide.
• harvest and processing into nori
sheets done by hand
• cultivated since 16th century
• “pole” method invented 1821
• nets across poles 1930’s
24. Europe
• Porphyra/Pyropia eaten in
Wales, Scotland, Ireland, N.
England, Norway, Finland.
• Called “laver” or “sloke”
• Pounded, stewed to jelly or
mixed with oats…
• 200 tonnes collected annually in
Wales until 1980’s (pollution)
25. Seaweed nutrition: minerals, Calcium
Dry weight (8g typical
serving)
•Ulva 37% RNI*
•Cheddar cheese 5% RNI
* RNI = UK version of recommended daily intake
Kombu/konbu
Wakame
Nori
Dulse
Irish moss
Sea lettuce
26. Seaweed nutrition: minerals, Iron
* RNI = UK version of recommended daily intake
Dry weight (8g typical serving)
•6.4mg Palmaria (dulse)
•1.6mg steak (raw sirloin)
•Bioavailability (absorption and
retention unknown for most
seaweeds)
•One study found lower
bioavailability in Porphyra sp.
Kombu/konbu
Wakame
Nori
Dulse
Irish moss
Sea lettuce
27. fatty acids
fatty acids
• Humans require omega-3 and
omega-6 fatty acids in diet.
• Seaweeds up to 2% dry weight
of lipids, mostly fatty acids.
• In fact, are the producers of the
fatty omega-3 and omega-6
fatty acids in fish, shellfish.
28. vitamins
vitamins
• Have fat-soluble and water-
soluble vitamins
• Produced by seaweed to
protect against damage caused
by uv light
• One of few plant sources of
B12.
29. protein
protein
• Some species relatively high in
protein
• Porphyra/Pyropia can be up to
47% protein (dry weight)*
• Bioavailability improved by
“physical processes” or
fermentation.
*Varies by season and species
35. Materials
• Bull kelp stipes used by
some First Nations for
fishing lines, ropes, bulbs
as containers.
• Tough stipes of some
species used to make
beach hockey sticks.
Holdfasts carved into round
hard balls.
48. • If required, get a license
(Alaska, Washington,
California)
• Know your limits (10lbs /
day wet weight in
California)
How to collect
seaweeds
sustainably
Guidelines from: Jennifer Hahn. 2010. Pacific Feast. Skipstone.
49. How to collect
seaweeds
sustainably
• Don’t pick whole
seaweed
• Take from blades well
above growing zone
(meristem)—on a kelp,
this is between stipe and
blade
• Use scissors or knife if
possible
meristem
cut here
Guidelines from: Jennifer Hahn. 2010. Pacific Feast. Skipstone.
50. How to collect
seaweeds
sustainably
• Don’t pick whole
seaweed
• Take from blades well
above growing zone
(meristem)—on a kelp,
this is between stipe and
blade
• Use scissors or knife if
possible
cut here
Guidelines from: Jennifer Hahn. 2010. Pacific Feast. Skipstone.
51. • Collect only a little across
the whole bed
• Collect only what you
need
• Leave holdfasts
• Be aware of what you’re
walking on (don’t crush
the animals!)
How to collect
seaweeds
sustainably
Guidelines from: Jennifer Hahn. 2010. Pacific Feast. Skipstone.
52. • Collect only from clean
sites
• Be respectful of
traditional First Nations’
land
How to collect
seaweeds
sustainably
Guidelines from: Jennifer Hahn. 2010. Pacific Feast. Skipstone.
What’s the use? game. images of products with seaweeds—what is the seaweed doing or how is it used?
Will focus on uses of seaweeds
brief recap of what seaweeds are for any new audience (have stus explain)
Photo of Louis Druehl, Canadian Kelp Resources, not sure of source or date, probably around 2003.
Brainstorm bunch of examples of how seaweeds used either today or historically. Try to be specific. Make list (to be categorized later during contemporary use section)
Brainstorm bunch of examples of how seaweeds used either today or historically. Try to be specific. Make list (to be categorized later during contemporary use section)
Seaweeds are found throughout the world's oceans and seas and are used in varying degrees by every culture with access to the oceans.
If, like me, you’re from a more Western background then this might be surprising— you might think of seaweeds as being used for only sushi or other food. Or you might think it is only a contemporary phenomenon, a new “fad”.
This is not the case, as we’ll explore, the relationship between people and seaweeds is much richer and deeper than you might expect. In fact, people have been using seaweeds for thousands of years….
Most seaweeds have no hard parts that preserve well—those that do aren’t edible by people—as such, hard to find evidence of seaweed use by people from pre-historic times. However, are a few examples.
May have influenced migration of peoples into Americas, a so-called “kelp highway”
– people entered Americas via land bridge “beringia” ~16000 yrs ago
– not known if route used was coastal, inland or both.
– one hypothesis that coastal people used coastal resources—fish, seaweeds, shellfish—and similar resources along long distances expedite migration south.
– idea that peoples travelled along coast, using river basins to migrate inland, explore inland as they travelled. Once established, many groups subsisted on mix of coastal/inland resources even if living many km from coast. Also travelled these routes to trade with other groups.
– evidence for this in South American site Monte Verde, Chile. Extremely well-preserved site, 14,600 yrs old (upper layer).
– distance is HOW MANY KM? from beringia, yet people here in less than 2000 yrs.
– 10 spp. seaweeds recovered here, site is 90km from coast and 15km from inland marine bay.
– species found include mazzaella, macrocystis, porphyra species we have in canada (support for similar spp. easier to migrate)
– also non-edible species like sargassum (we have in canada), suggesting used for medicinal as well as food purposes
– flecks of mazzaella, porphyra on blades indicates they were chopped, worked in some ways.
– evidence some were dried, probably for storing or travel back to coast
– evidence used seaweeds year round (drying) and seasonal availability of species
– people in this area accustomed to using coastal resources year-round, together with interior food, coastal seaweeds important for their survival.
– site is a peat bog so acidity of soil prevented bacterial decay.
kelp highway” Dillihey monte verde paper
Resources:
– dillihey paper
– pictures: http://www.pasthorizonspr.com/index.php/archives/10/2011/the-seaweed-trail-peopling-the-americas
– Unesco site: http://whc.unesco.org/en/tentativelists/1873/
– have harvested porphyra/pyropia in wild for production of nori since 6th century.
– cultivation began in 16th century (500 years ago)
– for many centuries, cultivation output was modest. Everything done manually (harvest, cultivation, prep of seaweed into sheets of nori)
– for many centuries, nori fishers gathered what they could find at low tide.
– in 1821, innovation by Jinbei Ohmiya who invented the pole method. Poles placed in shallow sandbanks and success depended on spores of porphyry settling and growing.
– in 1930’s, began suspending nets between poles, improving surface area on which spores could settle, better access to light. Lead to a 10x increase in yield
– remained low-yield until 1960’s when work of scientist Kathleen Drew
RESOURCES:
– info from Mouritson book
– Image from Utagawa Hiroshige (1857) http://en.wikipedia.org/wiki/One_Hundred_Famous_Views_of_Edo
– have harvested porphyra/pyropia in wild for production of nori since 6th century.
– cultivation began in 16th century (500 years ago)
– for many centuries, cultivation output was modest. Everything done manually (harvest, cultivation, prep of seaweed into sheets of nori)
– for many centuries, nori fishers gathered what they could find at low tide.
– in 1821, innovation by Jinbei Ohmiya who invented the pole method. Poles placed in shallow sandbanks and success depended on spores of porphyry settling and growing.
– in 1930’s, began suspending nets between poles, improving surface area on which spores could settle, better access to light. Lead to a 10x increase in yield
– remained low-yield until 1960’s when work of scientist Kathleen Drew
RESOURCES:
– info, images from Mouritson seaweeds sustainable, edible available book
–
RESOURCES:
– info from Mouritson book
– Image from Utagawa Hiroshige (1857) http://en.wikipedia.org/wiki/One_Hundred_Famous_Views_of_Edo
– until work of Drew, years when the porphyry crop failed and no one knew why.
– What Drew discovered in her research, studied the related species porphyry umbilicus in europe
RESOURCES:
– deep sea news: http://deepseanews.com/2013/11/weed-of-the-week-the-phycologist-that-launched-a-billion-dollar-industry/
Modern nori aquaculture had its begin- nings in 1949 when the filamentous Conchocelis-phase in the life history of Porphyra was identified and characterized by the British phycologist Kathleen M. Drew-Baker (Drew 1949), which led to the seeding of ropes from artificially cultivated Conchocelis-phases. In the latter part of the 20th century, some 300000 tonnes wet weight of Porphyra
nori growing in Japan is a multi-billion dollar industry — the single big- gest aquacultural enterprise being undertaken anywhere
As well as simple growth and propagation, some genetic selec- tion of nori has been undertaken to produce longer fronds in which fertility is delayed, permitting a greater interval of growth before the onset of spore production and subsequent frond erosion
(above from Turner 2003 paper)
April 14th still celebrated as “Mother of the Sea” day.
A great example of science for it’s own sake having an application after the fact.
– Many modern and ancient human populations with access to the seashore has used seaweeds in one way or another. Over 500 different species used in human history.
– 2000 years, China; 400 years ago in Scotland
– First Nations groups like the Coast Salish are well-documented as using seaweeds for many purposes. –
– for three main purposes: fodder, chemicals and food.
– Source: Graham & Wilcox
Photos: Top left, Chondrus harvest in PEI (http://www.tourismpei.com/photo-contest-2010), lower left, Ecklonia harvest in South Africa (algaebase.org), right, Eucheuma harvest in Zimbabwe (algaebase.org)
CONTEMPORARY USE SECTION
here have TPS to categorize the brainstormed list of ways seaweeds used contemporarily.
- suitable for vegetarians: agarose instead gelatine, carageen as thickener in dairies
- cosmetic and health: positive effect on e.g. psiorisas; I once listened to a beautyful speech in Lancaster, UK from Jane Teas (Jane.Teas@PalmettoHealth.org): seaweeds and cancer
Even if you have a very traditionally-Western diet – which does not make much direct use of seaweed as food – you’ve probably consumed something that contains at least an extract of seaweed in it recently.
Even though we still don’t fully understand seaweed biodiversity, we sure do make use of it! (though we could be using seaweeds much more than we currently do)
This man here is my friend and mentor, Dr. Louis Druehl. He’s a world-expert on kelps and other browns and worked for many years at Simon Fraser University. He now lives in Bamfield, west coast of Vancouver Island, and with his wife, Rae, runs a successful seaweed farm there. Here he is pulling up a crop of kelp.
Probably the most obvious use of seaweed by humans is as food. So let’s find out if you guys eat seaweed...
Photo source: (Not sure, a fellow student at Bamfield in 2003. Maybe Hana Kucera or Rodney Withall)
8g portion dry weight typical daily portion size in Asian cuisine.
Seaweeds as a food group not typically ingested in unprocessed form in Western diets to any great extent.
The single most important seaweed foods in the world are the Porphyra species.
In mainstream North American society they are considered “health foods”, and are sold as specialty and ethnic products in grocery stores and health food stores.
Put in 3 more difficult examples.
Nori has been farmed in Japan for over 300 years.
Since the 1940’s – when a seaweed biologist named Kathleen Drew Baker made a crucial discovery about the life history of Pyropia – nori farming has scaled up to become the biggest seaweed aquaculture industry in the world. The annual Pyropia harvest is estimated to be worth $2.5 billion dollars
– Pyropia is a good source of digestible protein – 25–35% dry weight of the plant is protein, most of which is digestible by humans.
– The economic success of crop seaweeds depends on detailed knowledge of the seaweeds themselves.
Photos: Pyropia specimen (Dan McDevit), nori farm (http://www.edenfoods.com/articles/view.php?articles_id=159), nori sheets (http://huntgatherlove.com/content/super-super-bowl-snack-ajitsuke-nori)
There are a few types of seaweeds that have been important to many cultures and nori is one of them. More correctly it’s called Pyropia, that’s the scientific name for Nori (nori being the final processed food).
On the Pacific Coast of North America, indigenous peo- ples have enjoyed a similarly long relationship with Porphyra species. The health and nutritional benefits pro- vided by Porphyra are widely appreciated by Northwest Coast indigenous peoples.
Table shows just sampling of names for Pyropia and related algae eaten by First Nations of BC
Gives a sense of how important was as a food source.
Fig. 3. Porphyra abbottae dried and ready to eat as a nutritious snack. Fig. 4. Porphyra abbottae cooked with salmon eggs, ready to be served, with cut squares of herring eggs on giant kelp (Macrocystis integrifolia Bory) (right).
– seaweeds are primary source of omega-3-fatty acids (all other marine orgs derive theirs from these and other algae). Are vital requirement for dev’t of complex brain and nervous system. (Mouritsen book, pg. 5) and affect cellular functions involved in ensuring a normal heart rate and coronary blood flow (nih site)
Minerals (table from MacArtain paper)
–The composition of seaweeds is known to vary according to the season and to the sampling techniques used; thus, the average values of components as reported in the available literature were used.
– Seaweeds exposed to many trace minerals due to marine habitat and are high in minerals compared to terrestrial sources of food.
– amount absorbed varies by species and location.
– important minerals like calcium and iron much higher in seaweeds than many terrestrial spp.
– calcium: ulva 8g portion dry weight contains 37% of daily intake calcium for adult male (UK standards)
Minerals (table from MacArtain paper)
– seaweeds are primary source of omega-3-fatty acids (all other marine orgs derive theirs from these and other algae). Are vital requirement for dev’t of complex brain and nervous system. (Mouritsen book, pg. 5) and affect cellular functions involved in ensuring a normal heart rate and coronary blood flow (nih site)
p.539: The habitat of seaweeds varies from species to species but many of them spend large amounts of time exposed to direct sunlight in an aqueous environment. As a result, seaweeds contain many forms of antioxidants, including vitamins and protective pigments. -- Highlighted oct 20, 2012
Reds, browns and greens each have compounds in their cell walls that protect their cells and help the seaweed stay upright in and out of the water. Globally, by far the main industrial use of seaweeds is in extracting these compounds from just a few different species of reds and browns. Used for commercial use as gelling agents to stiffen solutions and also as preservatives.
Agar from a few different types of red algae, like Gelidium.
Info source for chemical extracts: seaweeds.ie, Graham, Graham & Wilcox. 2009. The Algae. 2nd Edition. Pearson.
Photo source: Gelidium (algaebase.org). Agar plate: http://upload.wikimedia.org/wikipedia/commons/0/02/Salmonella_sp._on_DC-agar_from_Flickr_69017875.jpg
From red algae the compounds extracted called carrageenans come from relatively few types of red seaweeds, like Chondrus crispus (important historically in Canada, but today other genera used more for carrageenans, like Kappaphycus).
Photos: Chondrus (algaebase.org), powder (http://zailingtech.en.made-in-china.com)
From red algae the compounds extracted called carrageenans come from relatively few types of red seaweeds, like Chondrus crispus (important historically in Canada, but today other genera used more for carrageenans, like Kappaphycus).
Photos: Chondrus (algaebase.org), powder (http://zailingtech.en.made-in-china.com)
Compounds extracted from seaweeds – alginates, carrageenans, agars – too complex to synthesize.
– since we only make use of a few dozen species for chemical extracts, huge potential of chemical uses yet to be discovered.
Photo: Saccharina japonica (algaebase.org), alginate (http://www.dalchem.com.au/index.php?option=com_content&task=view&id=392&Itemid=346)
Coastal First Nations of northwestern North America, as well as using Porphyra species as food, have many other applications for macroscopic marine algae. Bull kelp (Nereocystis luetkeana (Mert.) Postels & Rupr.) stipes were cured for fishing lines, and the hollow floats were used as vessels for storing liquids such as seal oil. The tough stipes of some species were used to make beach hockey sticks and the holdfasts carved into hard, round balls for this game.
Brief tps to answer question.
Aquaculture vs. wildcaught info
The last human use I want to touch on is one that’s quite personal to me – the aesthetic of seaweeds, the sheer pleasure I get from the beauty of their form and how that beauty inspires me. They may look simple And I’m not the only one...
Photo: Macrocystis (algaebase.org)
I think that when you’re inspired by something – the way I’m inspired and invigorated by the beauty of seaweeds – that inspiration can ripple out and affect those around you in positive ways. As an example, the species I was so excited to describe, E. timburtonii, inspired my sister Meghan Clarkston to make this painting, and my friend Kathryn Roy to make these beautiful cupcakes (and, by coincidence, the fruit roll-up used on top likely contains seaweed!)
Example of seaweeds inspiring art, and seaweed used to make art.
stamps: http://www.alga-net.com/
designer sushi: http://www.designboom.com/weblog/cat/8/view/20710/lasercut-nori-for-designer-sushi.html
Not seaweeds!
Still so much we don’t know about the fundamental information of seaweeds: how many species, where they live, how to tell them apart. Until we do, cannot reliably assess the properties and potential use of most species (give example of mistaken identity, pic of two identical yet different taxa–ulva? with question marks on them)
They may look simple or uninteresting from far away or when they’re rotting, but take a look up close and in their element and I think you’ll be inspired too.
END W/ CONSERVE ONLY WHAT WE LOVE QUOTE??
Photo: Phycodrys (algaebase.org)