to increase supply. Similar to water reclamation
there is a lesser known need for phosphorous
reclamation, since our current practice is to mine
and refine phosphorous deposits, fertilize our
crops, and then let the phosphorous run directly
off of fields and into the ocean, or through our
wastewater treatment systems into the ocean
where it causes eutrophication damage. Economically mineable phosphorous is expected to
be scarce by 2050 or 2100, and production might
decline by 2030 raising its price possibly beyond
the reach of poorer farmers (Childers et al. 2011).
Fortunately, phosphorous can be recycled by
better farming practices or by using more aquatic
plants and other methods to recapture more than
the current rate of 50% from human wastes.
Given the water and fertilizer scarcities, this
century will likely pose to billions of people we
sincerely hope that duckweed-based water treatment systems, and many other water and nutrient
reclamation technologies will be applied at larger
scale to “close the loop” and avoid scarcity.
Today there is even the option to genetically
engineer many different species of the duckweed
family. There have been over 20 transgenic
therapeutic proteins that could improve human
health, reaching as high as 7% of total soluble
protein (Balaji et al. 2016), and the door is open
for many other types of transgenes like industrial
enzymes, those that improve nutritional content
of animal feed (Ghosh et al. 2018), and edible
vaccines expressed in duckweed for livestock
feed (Firsov et al. 2018). While some of these
transgenic duckweeds could be used whole,
others will go through an extraction process to
isolate the protein, especially the therapeutic
proteins. These extraction products may also
isolate other high value products like vitamin E
and omega-3 fatty acids before proceeding to
further processing. As described in Chap. 1,
modern agriculture often leads into a feedstock
being processed into a wide range of chemical
compounds that can be used as ingredients in
other finished goods, aka biorefining. This has
occurred with corn and soy finding their way into
a wide variety of products like emulsifiers and
gums, soy-based inks, and baby powder. For
example, duckweed protein and therapeutic
proteins specifically, can be isolated, perhaps
secondary metabolites could be alcohol extracted, and then the starch can be digested into
simple sugars that can be isolated or fermented
into ethanol, butanol, or polylactic acid. Additionally hydrothermal liquefaction could turn
duckweed biomass at any point in that process to
into natural gas, biochar, and a bio-crude oil that
could be fractionated into countless chemical
compounds. Maybe in the future, if duckweed
becomes a cheap and common crop, it will find
its way into tea, cosmetics, pet foods, garden
products, and other diverse finished goods. In
some cases in the future people may look at
duckweed thinking that the sum of its parts are
greater than the whole.
Thanks to their ability to clean wastewater
while providing food and fresh air, duckweeds
can be arguably seen as not only a crop species,
but also a life support system. In order to create a
life support system with low resupply needs for
long-term space travel, NASA has been investigating plant-based life support for decades and
specifically duckweed-based life support since
1966 (Landolt and Kandeler 1987). Therefore,
Space Lab Technologies, LLC is currently collaborating with the University of Colorado at
Boulder on a Phase 2 grant from NASA to
develop the µG-LilyPondTM growth chamber as
part of a plant-based life support system (Escobar
and Escobar 2017). Thanks to their high growth
rate, ability to grow in shallow trays, preference
for ammonia, simple aquatic lifestyle, ability to
grow and thrive in microgravity, high carbon
dioxide tolerance, and entirely edible nutritious
biomass duckweed is currently the prime candidate for the job. Presently, it is designed to provide fresh food, and oxygen, with the eventual
goal of converting urine to clean water. Part of
their project is studying how bursts of
high-intensity light can stimulate production of
carotenoids, vitamin E, and other nutritious secondary metabolites (Demmig-Adams and Adams
2002), since these and other vitamins have limited shelf stability meaning they must be produced onboard to enable longer flights. This
intimate reliance on duckweed in a closed-loop
system provides both a technical and symbolic
18 Future Prospects of Duckweed Research and Applications
183
there is a lesser known need for phosphorous
reclamation, since our current practice is to mine
and refine phosphorous deposits, fertilize our
crops, and then let the phosphorous run directly
off of fields and into the ocean, or through our
wastewater treatment systems into the ocean
where it causes eutrophication damage. Economically mineable phosphorous is expected to
be scarce by 2050 or 2100, and production might
decline by 2030 raising its price possibly beyond
the reach of poorer farmers (Childers et al. 2011).
Fortunately, phosphorous can be recycled by
better farming practices or by using more aquatic
plants and other methods to recapture more than
the current rate of 50% from human wastes.
Given the water and fertilizer scarcities, this
century will likely pose to billions of people we
sincerely hope that duckweed-based water treatment systems, and many other water and nutrient
reclamation technologies will be applied at larger
scale to “close the loop” and avoid scarcity.
Today there is even the option to genetically
engineer many different species of the duckweed
family. There have been over 20 transgenic
therapeutic proteins that could improve human
health, reaching as high as 7% of total soluble
protein (Balaji et al. 2016), and the door is open
for many other types of transgenes like industrial
enzymes, those that improve nutritional content
of animal feed (Ghosh et al. 2018), and edible
vaccines expressed in duckweed for livestock
feed (Firsov et al. 2018). While some of these
transgenic duckweeds could be used whole,
others will go through an extraction process to
isolate the protein, especially the therapeutic
proteins. These extraction products may also
isolate other high value products like vitamin E
and omega-3 fatty acids before proceeding to
further processing. As described in Chap. 1,
modern agriculture often leads into a feedstock
being processed into a wide range of chemical
compounds that can be used as ingredients in
other finished goods, aka biorefining. This has
occurred with corn and soy finding their way into
a wide variety of products like emulsifiers and
gums, soy-based inks, and baby powder. For
example, duckweed protein and therapeutic
proteins specifically, can be isolated, perhaps
secondary metabolites could be alcohol extracted, and then the starch can be digested into
simple sugars that can be isolated or fermented
into ethanol, butanol, or polylactic acid. Additionally hydrothermal liquefaction could turn
duckweed biomass at any point in that process to
into natural gas, biochar, and a bio-crude oil that
could be fractionated into countless chemical
compounds. Maybe in the future, if duckweed
becomes a cheap and common crop, it will find
its way into tea, cosmetics, pet foods, garden
products, and other diverse finished goods. In
some cases in the future people may look at
duckweed thinking that the sum of its parts are
greater than the whole.
Thanks to their ability to clean wastewater
while providing food and fresh air, duckweeds
can be arguably seen as not only a crop species,
but also a life support system. In order to create a
life support system with low resupply needs for
long-term space travel, NASA has been investigating plant-based life support for decades and
specifically duckweed-based life support since
1966 (Landolt and Kandeler 1987). Therefore,
Space Lab Technologies, LLC is currently collaborating with the University of Colorado at
Boulder on a Phase 2 grant from NASA to
develop the µG-LilyPondTM growth chamber as
part of a plant-based life support system (Escobar
and Escobar 2017). Thanks to their high growth
rate, ability to grow in shallow trays, preference
for ammonia, simple aquatic lifestyle, ability to
grow and thrive in microgravity, high carbon
dioxide tolerance, and entirely edible nutritious
biomass duckweed is currently the prime candidate for the job. Presently, it is designed to provide fresh food, and oxygen, with the eventual
goal of converting urine to clean water. Part of
their project is studying how bursts of
high-intensity light can stimulate production of
carotenoids, vitamin E, and other nutritious secondary metabolites (Demmig-Adams and Adams
2002), since these and other vitamins have limited shelf stability meaning they must be produced onboard to enable longer flights. This
intimate reliance on duckweed in a closed-loop
system provides both a technical and symbolic
18 Future Prospects of Duckweed Research and Applications
183