CONWAY, Ark. (March 26, 2010) – Seventeen Hendrix College students recently presented their research at the national meeting of the American Chemical Society in San Francisco. The theme for the society’s 239th national meeting was “Chemistry for a Sustainable World” and focused on using chemistry to improve the global environment.
The students, accompanied by chemistry faculty and staff members from Hendrix, prepared research posters and shared their research with conference attendees from throughout the world. Student research projects ranged from the chemical communication of mammals to venom variations in coral snakes.
With more than 161,000 members, the American Chemical Society (ACS) is the world’s largest scientific society and one of the world’s leading sources of authoritative scientific information. A nonprofit organization, chartered by Congress, ACS is at the forefront of the evolving worldwide chemical enterprise and the premier professional home for chemists, chemical engineers and related professions around the globe.
Students and their presentations included:
- Patrick D. Rawhouser, Arlington, Texas; senior chemistry major - Dependence of Styrene Cluster Ion Fragmentation on Ion Formation Conditions. Styrene molecular clusters are created by adiabatic expansion of an argon/styrene mixture and photoionized using 193 nm and 248 nm light. Photoionized styrene cluster ions sometimes show even-odd intensity alternation in the mass spectrum. Cluster ions formed under conditions that do or do not lead to such alternation are studied in a tandem mass spectrometer. Fragmentation of mass-selected ions is observed, and the fragments are analyzed by time-of-flight mass spectrometry. Clusters formed under conditions that lead to alternation tend to lose neutral dimers. Clusters formed under conditions that do not lead to alternation tend to fragment to form a styrene trimer ion. These variations in fragmentation for cluster ions formed under varied expansion conditions show the effect of cluster internal energy.
- Annie Ahn, Conway; senior Biochemistry and Molecular Biology (BCMB) major – The Effect of Protein Size on Adsorption to Activated Charcoal. Peanuts and tree nuts have been found to cause over 80% of food-induced anaphylactic shock every year. There is no cure for peanut allergy, and the only treatment for accidental ingestion of peanut is the immediate injection of epinephrine. Activated charcoal is used in emergency departments as a treatment to adsorb ingested poison or drugs, but has not been used on food allergens. If charcoal can also bind food allergens, it could allow those substances to pass through the digestive tract without causing an allergic reaction. This study investigated the adsorption of proteins by activated charcoal. Proteins of known molecular weight were incubated individually or simultaneously with activated charcoal to determine the size preferences in adsorption by activated charcoal. The charcoal was removed by centrifugation and the results were analyzed by gel electrophoresis and quantitative protein assay. It was determined that smaller proteins bound preferentially to the activated charcoal when co-incubated with larger proteins.
- Allison Watts, Memphis, Tenn.; senior BCMB major – Coral Snake Venom Variations. The Eastern Coral snake is a highly venomous snake found on the east coast from North Carolina to Florida and westward to Louisiana. Coral snake venom is a complex mixture of enzymes that is highly neurotoxic, affecting the nervous system of the individual that has been envenomated. Studies have shown that the venom of snakes varies between individuals, between populations, and between species. In this study, the venoms of two different coral snake species were compared to each other, and to the venom of the rattlesnake. The venom was analyzed to determine the level of activity of the enzymes acetylcholinesterase and phosphodiesterase. These are two key enzymes involved in the toxicity of these venoms. The results are important medically and for understanding the ecology and evolution of snake venoms.
- Thomas Blacklock, Benton; senior chemistry major – Adsorption of Peanut Protein Allergens by Activated Charcoal. Approximately 30,000 food-induced anaphylactic events are reported in emergency departments annually with about 80% caused by peanuts or tree nuts. Activated charcoal is used as a treatment for accidental ingestion of drugs and poisons due to its ability to adsorb toxic substances. However activated charcoal is not used to treat reactions to food allergens. This project investigates the potential of activated charcoal to eliminate or reduce the severity of an initial allergic reaction and the possibility of activated charcoal present in the gastrointestinal tract from an earlier administration to prevent the initiation of a second-phase, or biphasic, reaction. The rate and extent of peanut protein binding to activated charcoal is investigated in vitro at pH 2 and pH 7, simulating gastric and intestinal acidities. The efficiency of protein adsorption by activated charcoal under these in vitro conditions suggest the potential efficacy of its clinical use for this purpose.
- Jadon Wiese, Conway; junior BCMB major – Development of an ATR-FTIR flow reactor to study heterogeneous reactions on mineral dust surfaces as a function of relative humidity. Mineral aerosol has significant impacts on global climate, atmospheric chemistry, biogeochemical cycles, visibility and health. However, current knowledge of mineral aerosol surface chemistry in the atmosphere is limited to experimental studies performed under dry conditions. An Attenuated Total Reflection-Fourier Transform Infrared Spectrometer flow reactor has been developed and characterized to study the heterogeneous chemistry of mineral dust surfaces in the atmosphere as a function of relative humidity.
- Cameron Crane, Hiwasse; junior BCMB major – Toward understanding the effects of mineral dust aerosol heterogeneous chemistry: Impacts on ocean bioproductivity. Iron is the fourth most abundant element on Earth’s crust and serves as an important micronutrient for ocean bioproductivity. As bioavailable (soluble) iron is the primary form of iron accessible to phytoplankton, iron dissolution studies to determine the effects of atmospheric processing of mineral dust surfaces on iron bioavailability are being explored. Results of these studies will help us understand the effects of mineralogy, particle size, and atmospheric heterogeneous chemistry on phytoplankton growth and thus CO2 sequestration.
- Tyler Lewis, Hot Springs; junior BCMB major – Mitochondrial DNA Damage by Alcohol in HepG2 Cells. Alcohol intake damages the liver. How does alcohol damage the liver? We propose that alcohol transformations (i.e. metabolism) in the liver produce toxic substances that damage DNA (the blueprint of life) in mitochondria, the cell’s powerhouse. In this work, we discovered that alcohol induced mitochondrial DNA damage only in cells actively metabolizing alcohol.
- Kerry Evans, Little Rock; senior biology major – Effects of Iron Incorporation in Cultured Hepatocytes. Iron is toxic to the liver. How does iron damage the liver? We propose that iron is not toxic by itself, but it is activated to toxic forms by transformations occurring in the liver. In this work, we discovered that iron produces damage to DNA (the blueprint of life) only in cells that overexpress a protein (CYP2E1) induced in alcoholism. We propose that CYP2E1 is an active protein that activates iron to biologically toxic forms.
- Jonathan Tackett, Lonoke; junior BCMB major – Mitochondrial DNA damage by docosahexaenoic and iron in HepG2 cells. Omega-3 fatty acids are common food additives and dietary supplements that have shown health benefits. However, they are highly reactive with oxygen, and might generate toxic products through oxidation. In this work, we discovered that a model omega-3 fatty acid (docosahexaenoic acid from fish oil) is toxic to liver cells only in combination with iron and overexpression of a protein (CYP2E1) induced in alcoholism.
- Stefoni Stratton, Little Rock; senior BCMB major – Cytotoxicity by CYP2E1 Overexpression in HepG2 Cells. Polyunsaturated fatty acids such as arachidonic acid are present in vegetable oils and are important food components. However, they are highly susceptible to oxidation and might produce damage to cellular components. In this work, we discovered that a model polyunsaturated fatty acid (arachidonic acid) is toxic to liver cells only at high concentrations in cells that overexpress a protein (CYP2E1) involved in alcohol metabolism.
- Mike Weng, Little Rock; senior BCMB major – Mitochondrial DNA Damage by Arachidonic Acid and Iron in HepG2 Cells. Polyunsaturated fatty acids such as arachidonic acid present in vegetable oils are important food components. However, they are highly susceptible to oxidation and might produce damage to cellular components. In this work, we discovered that a model polyunsaturated fatty acid (arachidonic acid) is toxic to liver cells at very low concentrations only in cells that are loaded with iron and overexpress a protein (CYP2E1) involved in alcohol metabolism.
- Blake Burkert, Fort Smith; senior BCMB major – Mammalian chemical communication: Comparative investigation of urinary signals in prosimian primates. This project, in collaboration with Duke University scientists, examines volatile organic chemicals in the urine of 12 species of lemurs. The objective was to determine if there was a clear difference between those species that are believed to rely on urine for chemical communication with one another versus those species that rely more on glandular secretions for chemical communication. Lemurs, which are endemic to Madagascar alone, are for the most part endangered species, thus is it important to learn as much about them as possible to try and help in their long-term survival.
- Innocent H. Hirwa, Musanze, Rwanda. This project, in collaboration with scientists from the State University of New York-Stony Brooke, the Queensland, Australia, Primary Industries and Fisheries, and the University of California at Berkeley, examines volatile organic chemicals in the urine of a specific type of lemur, the Milne-Edwards’ sifaka. The goal was to identify specific volatile organic chemicals in the secretions from the anogenital gland that singly or in groups might be characteristic of sex or family. Research has identified clear differences between male and female glandular chemicals, which are likely used in chemical communication. Lemurs, which are endemic to Madagascar alone, are for the most part endangered species, thus is it important to learn as much about them as possible to try and help in their long-term survival.
- Zach J. Waldrip, Batesville; senior BCMB major. This project, in collaboration with scientists from Western Kentucky University, the Oregon Health & Science University, and George Mason University, is examine the differences between volatile organic chemicals in the urine of mature male elephants that are in the rut-like state of musth (high testosterone, heightened aggression, more success in mating) or not in musth. We have found significant differences which indicate that other elephants can assess the physiological state of the male elephant by urinary chemical communication. We have also determined that the urine chemistry changes after the urine is expelled, likely due to environmental bacterial effects. These changes may allow other elephants to assess the time elapsed since a musth male was in their area. Elephants are endangered and threatened in the wild due to poaching for ivory and habitat encroachment by humans. It is therefore important to learn as much about them as possible to try and aid in their long-term survival.
- Leanne E. Mathurin, Baton Rouge, La.; chemistry and history major – Dirt as a measure of water wellness and an indicator of historical land use. Leanne has done environmental testing of local lake water samples and has extended this analysis to investigate chromium in the lake sludge samples. The samples tested come from Lake Conway, a major fishing lake, and Brewer Lake, the municipal water supply. Both of these lakes are under development pressure from population growth (Lake Conway) or shale oil drilling in the water shed (Brewer Lake). Chromium can be found naturally in dirt but can also be part of industrial run off and archaic pesticide residues.
- John A. Christie, Little Rock; chemistry and mathematics double major – Chemical education and scientific literacy for non-science majors. Science literacy is a broad goal that all science teachers share, but it is difficult to define and assess. We have worked to create a functional definition and translate it into an easily used rubric. From here, we have developed a series of teaching materials based on environmental chemistry using Beijing air quality, local air quality, bottled water analysis, and a capstone poster session that develop scientific literacy. Importantly, these activities are readily translated for any of the STEM discipline.
- Daniel J. Ward, Tacoma, Wash.; senior chemistry major – Investigations of inorganic metabolites H2S in liver cells by ion chromatography. Daniel’s senior capstone research project was a collaboration between Drs Liz Gron and Andres Caro both of Hendrix College. The chemical H2S has long been known as a toxin, but like so many other small molecules, it might have a secret life related to cell signaling activity. The research treated liver cells with H2S and then using ion chromatography to identify and quantify inorganic cell metabolites. This work was intended to unravel how H2S is taken in by the cell and the fate of H2S within the cell.
Hendrix, founded in 1876, is a selective, residential, undergraduate liberal arts college emphasizing experiential learning in a demanding yet supportive environment. The college is featured in the 2010 edition of the Princeton Review as one of the country’s best 371 colleges, was identified as the nation’s top “Up and Coming” liberal arts college for 2010 by U.S. News and World Report, and is ranked among 44 “Best Buy” colleges by the 2010 Fiske Guide to Colleges. Hendrix has been affiliated with the United Methodist Church since 1884. For more information, visit www.hendrix.edu.