Chemical Education Today
Research Advances: Capturing CO2 in a Bowl; Fructose, HMF, and Honeybees by Angela G. King* Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109
[email protected] Capturing CO2 in a Bowl The discovery of a bowl-shaped molecule that pulls carbon dioxide out of the air suggests exciting new possibilities for dealing with global warming, including genetically engineering microbes to manufacture such CO2 “catchers”. J. A. Tossell notes in his recent computational study that Philip Gale and colleagues discovered the macrocyclic amidourea molecule 1 while doing research unrelated to global climate change (Figure 1) (1, 2). Carbon dioxide was collecting in the molecule, and Gale realized that it was coming from air in the lab. Compound 1 traps CO2 through a complex in which a carbonate ion is held in place by a number of O-N-H bonds. Tossell recognized that these qualities might make it useful as an industrial absorbent for removing carbon dioxide directly from ambient air. Tossell's new computer modeling studies indicate the molecule might be well suited for removing carbon dioxide from the atmosphere, in addition to its previously described potential use as an absorbent for CO2 from electric power plants and other smokestacks. The calculation results indicate favorable energetics for formation of both CO3-2 and HCO3complex formation. Additionally, Tossell noted that preliminary calculations suggest the complex will form without the N-H containing groups being held in a macrocycle, which may allow for the design of CO2-trapping agents with streamlined syntheses. “It is also conceivable that living organisms may be developed which are capable of emplacing structurally similar ion receptors within their cell membranes”, the report speculates. Other approaches to CO2 trapping include metalorganic frameworks and terrestrial sequestration (3). Educators interested in incorporating a discussion of carbon dioxide trapping into their teaching should find Robelia's recent study on adding environmental focus to chemistry classes interesting (4). Heat Forms Potentially Harmful HMF in HFCS Researchers have established the conditions that foster formation of potentially dangerous levels of a toxic substance in the high-fructose corn syrup (HFCS) often fed to honeybees. Their study could also help keep the substance out of soft drinks and dozens of other human foods that contain HFCS. The 568
Journal of Chemical Education
_
_
Figure 1. An unusual bowl-shaped molecule (1) that pulls carbon dioxide out of the air may provide exciting new possibilities for dealing with global warming. Reproduced with permission from ref 1. Copyright 2009 American Chemical Society.
substance, hydroxymethylfurfural (HMF), forms mainly from heating fructose. In the new study, Blaise LeBlanc, Gillian Eggleston, and colleagues note HFCS's ubiquitous usage as a sweetener in beverages and processed foods. Some commercial beekeepers also feed it to bees to increase reproduction and honey production. When exposed to warm temperatures, HFCS can form HMF and kill honeybees. Some researchers believe that HMF may be a factor in Colony Collapse Disorder, a mysterious disease that has killed at least one-third of the honeybee population in the United States. The scientists measured levels of HMF in HFCS products from different manufacturers over a period of 35 days at different temperatures using the previously published Winkler method (5). As temperatures rose, levels of HMF increased steadily (Figure 2). HMF levels jumped dramatically at about 120 °F. “The data are important for commercial beekeepers, for manufacturers of HFCS, and for purposes of food storage. Because HFCS is incorporated as a sweetener in many processed foods, the data from this study are important for human health as well”, the report states. The new report notes that previous studies have linked HMF to DNA damage in humans. In addition, HMF breaks down in the body to other substances potentially more harmful than HMF. Additional information on honeybee research is available through the Carl Hayden Bee Research Center (6).
_
Vol. 87 No. 6 June 2010 pubs.acs.org/jchemeduc r 2010 American Chemical Society and Division of Chemical Education, Inc. 10.1021/ed100234u Published on Web 04/12/2010
Chemical Education Today
Figure 2. Rates of increase of HMF (ppm) with respect to time over 35 days at 31.5, 40.0, 49.0, and 68.8 °C. Reproduced with permission from ref 5. Copyright 2009 American Chemical Society.
Literature Cited 1. Tossell, J. Catching CO2 in a Bowl. Inorg. Chem. 2009, 48, 7105– 7110. 2. Brooks, S.; Gale, P.; Light, M. Anion-Binding Modes in a Macrocyclic Amidourea. Chem. Commun. 2006, 41, 4344–4346. 3. See Omar M. Yaghi's Research Web site at http://www.chem.ucla. edu/dept/Faculty/yaghi.html#research (accessed Mar 2010) and the Carbon Sequestration in Terrestrial Ecosystems home page at http:// csite.esd.ornl.gov/ (accessed Mar 2010).
r 2010 American Chemical Society and Division of Chemical Education, Inc.
_
4. Robelia, B.; McNeill, K.; Wammer, K.; Lawrenz, F. J. Chem. Educ. 2010, 87, 216–220. 5. Le Blanc, B.; Eggleston, G; Sammataro, D; Cornett, C.; Dufault, R.; Deeby, T., St.; Cyr, E. Formation of Hydroxymethylfurfural in Domestic High-Fructose Corn Syrup and Its Toxicity to the Honey Bee (Apis mellifera). J. Agric. Food Chem. 2009, 57, 7369–7376. 6. Home page of the Carl Hayden Bee Research Center of the United States Department of Agriculture Agricultural Research Service. http://www.ars.usda.gov/Main/site_main.htm?modecode=53-42-0300 (accessed Mar 2010).
pubs.acs.org/jchemeduc
_
Vol. 87 No. 6 June 2010
_
Journal of Chemical Education
569
