Abstract: The impact of agriculture is a hugely debated topic. Growing crops such as cotton and coffee have high environmental impacts as they consume high amounts of water, land and pesticides. They are also a leading cause of deforestation. Just as animal cell agriculture, offers the best alternate solution for sustainable meat, in the long run, plant cell agriculture is the likely candidate for sustainable industrial crops.
Agriculture, the art of cultivating the soil, producing crops, and raising livestock, played a pivotal role in shaping human society. We already spoke about the impact of livestock raising with respect to meat and dairy.
One of the debated topics in agriculture is monoculture farming: a form of agriculture where only one particular crop is grown at one time on a specific field. While monoculture definitely has quite a few pros:
a. Better yield for crops such as cereals when sown and grown as monocultures based on specific climate conditions and, therefore, get higher revenue.
b. monoculture makes it easy for farmers to implement a fixed schedule of planting, harvesting and maintenance leading to increased efficiency and productivity
c. easier use of technologies such as drones for planting, satellite observation, sensors for crop monitoring etc.
it also comes with cons:
a. difficulty in pest management and therefore, higher use of pesticides
b. Monoculture affects the natural balance of soils leading to soil degradation while also consuming high land and water usage. This can also be attributed to
c. Artificial selection of crops to produce desired traits has been in practice since the early domestication era. This has lead to a loss of biodiversity, both at the species and the genetic level.
Loss of biodiversity is spoken less about as compared to climate change when it comes to the impact of agriculture as monoculture farming plays a substantial role in the extinction of wildlife species. They also amount to deforestation, although far less when compared to animal agriculture. Agricultural crops certainly have a role to play in greenhouse gas emissions as well, directly and indirectly. All of these can be attributed to the fact that cultivated crops require large areas of land and are also responsible for subsequent loss in soil fertility. Besides the pasture for animal feed, cocoa, coffee and cotton consume the largest share of cultivated land.
A few crops and their environmental impacts:
Cotton: Cotton is one of the most widely used fabrics. About 27 million tons of cotton are produced each year. There are concerns around child labour and environmental contamination in the cotton production process. It is also estimated that 10,000 litres of water are required to produce one kilogram of cotton. IT is also the crop that requires the most amount of pesticide.
Coffee: Coffee is among the most cherished beverages across the globe. Coffe plantations play a direct role in deforestation and hence decrease in biodiversity, interference with the migratory patterns of birds, and increase in the chance of disease and infestations. The average carbon footprint of Arabica coffee from Brazil and Vietnam was calculated as 15.33 (±0.72) kg CO2e kg−1 for conventional coffee production.
Cacao: Cacao is an essential ingredient of chocolate grown from cacao seeds which are also responsible for deforestation. Countries like Ghana and Ivory Coast have lost 70-80% of their forest cover since the 1950s. Cacao production is also responsible for child labour.
Although the accusation of child labour in the above cases is arguable since child labour is possibly a symptom of poverty in certain regions as compared to enforcement. Nevertheless, we need an alternate solution that is sustainable and provides the same performance characteristics, if not better.
Just as animal cell agriculture, offers the best alternate solution for sustainable meat, in the long run, plant cell agriculture is the likely candidate for industrial crops.
As discussed before, bio-revolution is going to fundamentally transform industrial applications. And one of the most interesting areas of innovative applications is cell culturing. Cell culture is a major tool in the field of biochemistry that has been used for decades in cellular and molecular biology. It has been used to study biochemistry cells such as aging, metabolic studies, drug screening and manufacturing of vaccines as well as proteins used in therapeutics.
Cell culture is the growth of cells belonging to microorganisms such as bacteria and yeast, plant, animal or human cells under controlled conditions in the laboratory. While largely used in therapeutics and research, cell culturing has recently paved way for a plethora of industrial applications while aiming to tackle sustainability problems.
Some of the applications of different cell culturing techniques are listed below:
Microbial Cell Culture:
Microbial cell cultures are widely used in molecular biology and clinical applications:
a. for cloning and recombinant protein expression.
b. to isolate, detect, and identify microbes that cause disease
c. recombinant Protein for milk and dairy
Insect Cell Culture:
Insect cell lines have been useful in
a. the development of alternatives to conventional chemical pesticides for agriculture
b.the creation of vaccines and pharmaceuticals for diseases.
c. in basic research in virology, endocrinology, molecular biology, genetics, and biochemistry.
Animal Cell Culture:
Animal cell cultures find applications in
a. model studying, virology, production of monoclonal antibodies and other proteins through genetic engineering, etc.
b. cell manufacturing to produce lab-grown meat and leather.
Plant Cell Culture:
Plant cell culturing technology has had a long tradition in healthcare, pharmaceuticals, cosmetics and the food industry. Eg: Plant cell-based cellular agriculture has been used to manufacture food supplement ingredients in bio-reactors. Mibelle Biochemistry was the first company to introduce plant stem cell culture extracts into the cosmetics industry in 2008.
But the demand for sustainable manufacturing of food and cosmetics products has brought a new wave of synbio applications.
Plant cell culture technology enables low-energy, low impact, and location as well as season independent growth/manufacturing products as compared to whole crops which consume a greater proportion of land, water and energy while being extremely dependent on season and location. In addition, certain characteristics of the product can also be improved through culture-medium composition and cultivation parameters. More importantly, the manufacturing process takes days and weeks using the cell-cultured process as compared to months in the conventional process.
Unlike mammalian cell culture, plant cell culture leverages inexpensive culture media and can scale much faster while providing greater protein yields.
Since crops and cosmetics are not products that are consumed by the human body, resource efficiency can be improved drastically through a process called cell immortalization. Usually, cells divide only a limited number of times and have only finite cell lines. Beyond a certain point, a genetically determined event known as senescence, they lose their ability to proliferate. However, certain cell lines can be made immortal through a process called transformation, which can be chemically or virally induced or sometimes occur naturally. The cell then acquires the ability to divide indefinitely becoming a continuous cell line. This enables the growth of cells in larger volumes than usual.
The plant cell culture technology works very similarly to the animal cell culture technology. An example of the technology for growing cotton would be as follows:
a. Cell Harvesting: A piece of the cotton plant such as the bud or leaf is isolated from the cotton plant and grown as callus (unorganized cell mass)
b. Cell Screening: Cell lines are screened and key genes for improved fiber length, are selected.
c. Cell Proliferation: Large stem cells are produced in seed train which has multiple growth phases in increasingly large containers
d. Cell Differentiation: Growth factors are introduced in the bioreactor to trigger cell differentiation or, in the case of cotton, fiber cell initiation
e. Cell Elongation: Cells are allowed to elongate and mature which result in cotton fibre in its purest form
f. Pre-Programming Characteristics: To achieve properties like a particular colour or antimicrobial characteristic, the fibres could be pre-programmed through genetic engineering
By integrating the initial steps in-vitro such as propagation, initiation and elongation, the cell-culturing process requires far less water, land, pesticides and transportation need as compared to the conventional processes.
Climate change, plant diseases and unsafe farming practices are driving the possibility of plant cell agriculture to grow crops such as cotton, coffee, cacao and possibly other food crops too. This relatively new field of application is slowly garnering interest and could see the next wave of synbio startups cropping up.
There are currently 2 startups in the pre-seed and seed stage leveraging plant cell culture technology.
- Galy: The most advanced of the lot is Galy, a US startup that is aiming to build a plant cell synbio platform with an initial focus on growing cotton. They also eventually grow food crips via their platform. They have raised less than a million dollars so far but are the leading company in the plant cellular agriculture space.
- California Cultured: Another US startup that was recently incubated at IndieBio, is aiming to produce sustainable chocolate from plant stem cells cultured. They have already produced the first cell-cultured chocolate bar grown in a low-cost, high performance, food-grade cacao cell media.
- Indie Bio interview with California Cultured CEO Alan Persltein