Agricultural chemistry

This aspect of agricultural chemistry deals with the role of molecular chemistry in agriculture as well as the negative consequences.

Plant biochemistry encompasses the chemical reactions that occur within plants. In principle, knowledge at a molecular level informs technologies for providing food. Particular focus is on the biochemical differences between plants and other organisms as well as the differences within the plant kingdom, such as dicotyledons vs monocotyledons, gymnosperms vs angiosperms, C2- vs C4-fixers, etc.

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Chemical materials developed to assist in the production of food, feed, and fiber include herbicides, insecticides, fungicides,{{cite book |doi=10.1002/0471238961.0621140704180509.a01 |chapter=Fungicides, Agricultural |title=Kirk-Othmer Encyclopedia of Chemical Technology |date=2000 |last1=Dreikorn |first1=Barry A. |last2=Owen |first2=W. John |isbn=978-0-471-48494-3 }} and other pesticides. Pesticides are chemicals that play an important role in increasing crop yield and mitigating crop losses.{{cite journal |last1=al-Saleh |first1=I. A. |title=Pesticides: a review article |journal=Journal of Environmental Pathology, Toxicology and Oncology |date=1994 |volume=13 |issue=3 |pages=151–161 |id={{INIST|3483983}} |pmid=7722882 }} These work to keep insects and other animals away from crops to allow them to grow undisturbed, effectively regulating pests and diseases.

Disadvantages of pesticides include contamination of the ground and water (see persistent organic pollutants). They may be toxic to non-target species, including birds, fish,{{cite journal |last1=Aktar |first1=Wasim |last2=Sengupta |first2=Dwaipayan |last3=Chowdhury |first3=Ashim |title=Impact of pesticides use in agriculture: their benefits and hazards |journal=Interdisciplinary Toxicology |date=March 2009 |volume=2 |issue=1 |pages=1–12 |doi=10.2478/v10102-009-0001-7 |pmc=2984095 |pmid=21217838 }} pollinators, {{cite journal |title=Food brands and retailers will scrutinize pesticides |journal=C&EN Global Enterprise |date=13 January 2020 |volume=98 |issue=2 |pages=33 |doi=10.1021/cen-09802-cover8 |doi-access=free |last1=Bomgardner |first1=Melody |last2=Erickson |first2=Britt }} as well as the farmworkers themselves.

File:Dead Zone NASA NOAA.jpg is caused by run-off of agricultural chemicals.{{cite web

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|title=NOAA: Gulf of Mexico 'Dead Zone' Predictions Feature Uncertainty

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|publisher=Louisiana Universities Marine Consortium (LUMCON)

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|title=What is hypoxia?

|url=http://www.gulfhypoxia.net/Overview/

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Agricultural chemistry often aims at preserving or increasing the fertility of soil with the goals of maintaining or improving the agricultural yield and improving the quality of the crop. Soils are analyzed with attention to the inorganic matter (minerals), which comprise most of the mass of dry soil, and organic matter, which consists of living organisms, their degradation products, humic acids and fulvic acids. {{cite book |doi=10.1002/0471238961.koe00021 |chapter=Soil Chemistry |title=Kirk-Othmer Encyclopedia of Chemical Technology |date=2016 |last1=Arai |first1=Yuji |pages=1–37 |isbn=978-0-471-48494-3 }}

Fertilizers are a major consideration. While organic fertilizers are time-honored, their use has largely been displaced by chemicals produced from mining (phosphate rock) and the Haber-Bosch process. The use of these materials dramatically increased the rate at which crops are produced, which is able to support the growing human population. Common fertilizers include urea, ammonium sulphate, diammonium phosphate, and calcium ammonium phosphate.{{cite book |doi=10.1016/B978-0-12-820560-0.00013-8 |chapter=Future Trends |title=Techno-Economic Challenges of Green Ammonia as an Energy Vector |date=2021 |last1=Rouwenhorst |first1=K.H.R. |last2=Elishav |first2=O. |last3=Mosevitzky Lis |first3=B. |last4=Grader |first4=G.S. |last5=Mounaïm-Rousselle |first5=C. |last6=Roldan |first6=A. |last7=Valera-Medina |first7=A. |pages=303–319 |isbn=978-0-12-820560-0 |s2cid=243358894 |chapter-url=https://hal.archives-ouvertes.fr/hal-03135310/file/200210%20Future%20Trends_v11.pdf }}{{cite journal |id={{Gale|A472372583}} |last1=Leghari |first1=Shah Jahan |last2=Wahocho |first2=Niaz Ahmed |last3=Laghari |first3=Ghulam Mustafa |last4=HafeezLaghari |first4=Abdul |last5=MustafaBhabhan |first5=Ghulam |last6=HussainTalpur |first6=Khalid |last7=Bhutto |first7=Tofique Ahmed |last8=Wahocho |first8=Safdar Ali |last9=Lashari |first9=Ayaz Ahmed |title=Role of nitrogen for plant growth and development: a review |journal=Advances in Environmental Biology |date=September 2016 |volume=10 |issue=9 |pages=209–219 }}

File:BiodieselRoutes.svg of backbone double bonds. Fatty acid methyl esters can then be produced by transesterification. Alternatively, C16 and C18 diesel fuels arise by hydrogenolysis of the saturated fat.|400px]]

Agricultural chemistry encompases the science and technology of producing not only edible crops, but feedstocks for fuels ("biofuels") and materials. Ethanol fuel obtained by fermentation of sugars. Biodiesel is derived from fats, both animal- and plant-derived. Methane can be recovered from manure and other ag wastes by microbial action.{{cite book |doi=10.1002/0471238961.trigmurz.a01 |chapter=Triglycerides and Oils for Biofuels |title=Kirk-Othmer Encyclopedia of Chemical Technology |date=2012 |last1=Murzin |first1=Dmitry Yu. |last2=Mäki-Arvela |first2=Päivi |last3=Simakova |first3=Irina L. |pages=1–14 |isbn=978-0-471-48494-3 }}{{cite book |doi=10.1002/0471238961.0621051211120119.a01.pub2 |chapter=Biomass Energy |title=Kirk-Othmer Encyclopedia of Chemical Technology |date=2003 |last1=Paisley |first1=Mark A. |isbn=978-0-471-48494-3 }} Lignocellulose is a promising precursor to new materials.{{cite journal |doi=10.1021/acs.chemrev.5b00345 |title=Strategies for the Conversion of Lignin to High-Value Polymeric Materials: Review and Perspective |date=2016 |last1=Upton |first1=Brianna M. |last2=Kasko |first2=Andrea M. |journal=Chemical Reviews |volume=116 |issue=4 |pages=2275–2306 |pmid=26654678 }}

File:D-Fructose vs. D-Glucose Structural Formulae V.1.svg

Biocatalysis is used to produce a number of food products. More than five biilion tons of high fructose corn syrup are produced annually by the action of the immobilized enzyme glucose isomerase of corn-derived glucose. Emerging technologies are numerous, including enzymes for clarifying or debittering of fruit juices.{{cite journal |doi=10.1039/c3cs35506c |title=Industrial Use of Immobilized Enzymes |date=2013 |last1=Dicosimo |first1=Robert |last2=McAuliffe |first2=Joseph |last3=Poulose |first3=Ayrookaran J. |last4=Bohlmann |first4=Gregory |journal=Chemical Society Reviews |volume=42 |issue=15 |pages=6437–6474 |pmid=23436023 }}

A variety of potentially useful chemicals are obtained by engineered plants. Bioremediation is a green route to biodegradation.

Genetically Modified Organisms (GMO's) are plants or living things that have been altered at a genomic level by scientists to improve the organisms characteristics. These characteristics include providing new vaccines for humans, increasing nutrients supplies, and creating unique plastics.{{cite journal |last1=Bawa |first1=A. S. |last2=Anilakumar |first2=K. R. |title=Genetically modified foods: safety, risks and public concerns—a review |journal=Journal of Food Science and Technology |date=December 2013 |volume=50 |issue=6 |pages=1035–1046 |doi=10.1007/s13197-012-0899-1 |pmc=3791249 |pmid=24426015 }} They may also be able to grow in climates that are typically not suitable for the original organism to grow in. Examples of GMO's include virus resistant tobacco and squash, delayed ripening tomatoes, and herbicide resistant soybeans.

GMO's came with an increased interest in using biotechnology to produce fertilizer and pesticides. Due to an increased market interest in biotechnology in the 1970s, there was more technology and infrastructure developed, a decreased cost, and an advance in research. Since the early 1980s, genetically-modified crops have been incorporated. Increased biotechnological work calls for the union of biology and chemistry to produce improved crops, a main reason behind this being the increasing amount of food needed to feed a growing population.{{cite journal |title=Perspectives: Chemistry seeks its new level in agtech |journal=C&EN Global Enterprise |date=3 July 2017 |volume=95 |issue=27 |pages=22–23 |doi=10.1021/cen-09527-scitech2 |last1=Meadows-Smith |first1=Marcus |last2=Meadows-Smith |first2=Holly }}

That being said, concerns with GMO's include potential antibiotic resistance from eating a GMO. There are also concerns about the long term effects on the human body since many GMO's were recently developed.

Much controversy surrounds GMO's. In the United States, all foods containing GMO's must be labeled as such.{{cite journal |title=House clears GMO food labeling bill |journal=C&EN Global Enterprise |date=18 July 2016 |volume=94 |issue=29 |pages=16 |doi=10.1021/cen-09429-notw11 |doi-access=free |last1=Erickson |first1=Britt }}

Particularly relevant is proteomics as protein (nutrition) guides much of agriculture.

• Agronomy
• Food science

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Category:Agriculture

Category:Biochemistry