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Have you ever wondered why people "pass gas"? Whether you think this is funny or not, everyone has intestinal gas. You probably know that certain foods, like baked beans, will produce an increased amount of this gas. On the average, everyone releases about a quart of gas every day (about 14 expulsions). Biotechnology has been used to develop a cure for that certain someone who gives off more gas than you ever thought possible. These days people are into eating healthier foods. This means a diet with a lot of fruits, vegetables (especially beans and peas), milk products, bran and whole grain. The problem with this healthy diet is that these foods are major gas producers. In our society today, "passing of gas" has yet to become socially acceptable (just try it sometime in class!). To the relief of many of us, researchers at Lactaid,Inc. have used the tools of biotechnology to find a way to lower production, and more importantly, expulsion of rectal gas. More than 99% of intestinal gas or "flatus", as the socially polite like to say, is composed of odorless gases, like carbon dioxide, nitrogen and oxygen. The remaining gas can be extremely noxious and humans can notice them at one part per 100 million parts of air. This gas is produced when complex sugars that humans can't digest are passed along to E. coli bacteria that live in our large intestine. E. coli metabolize these compounds that are untouched by our digestive process, thereby creating hydrogen and other smelly gases. If these complex sugars can somehow be broken down before they reach the intestinal bacteria, you will breathe a lot easier. You may notice that some people have more of a gas problem than others even after eating the same food. This is because the ratio of the two types of intestinal bacteria - those that can break down sugars and those that can't, vary from person to person. It is this ratio that dictates how much gas one will pass. Lactaid, Inc. has designed an amazing product, Beano. This gas eliminator contains the enzyme alpha-galactosidase which breaks down those complex sugars found in gas producing foods. Biotechnology plays an important role in this gas prevention project. Scientists have found a way to mass produce the enzyme alpha-galactosidase. The fungus Aspergillus niger was genetically engineered by inserting a copy of the gene for alpha-galactosidase into the genome of this fungus. Further manipulations of the fungi causes them to secrete the enzyme in a form that can be dissolved in glycerol and water. Alpha-galactosidase happens to resemble soy sauce in taste so it can be applied to most food without changing the flavor too drastically. Background information was excerpted with permission from Biotechnology Resources for Teachers, page 7, "Hey Who Farted". This resource book can be purchased from the Massachusetts Biotechnology Research Institute, One Innovation LDrive, Worcester, MA 01065 for $29.50.The purpose of this lab is to experiment with Beano, beans and E. coli in order to determine the effectiveness of alpha-galactosidase in breaking down galactose in beans thus reducing flatus. Whenever scientific experiments are done, it becomes very important to be able to quantify or measure your results. In order for this process not to be too gross, I have designed a test tube system to collect and measure the gas produced by E. coli as they break down beans. You should keep the following information in mind as you design your experiment. Be sure to use positive and negative controls in your experiment. Be sure to measure everything - the beans, the amount of E coli culture, the amount of Beano, the length of time it takes to produce the gas and the amount of gas produced. You should prepare three test tube systems for each control and experimental test. You should develop a data collection chart before you begin this experiment. Materials E. test tube systems for collecting gas pipettes & pipump test tube rack Beans incubated overnight with Beano Beans incubated overnightwithout Beano Glucose test strips Galactose Beano Lab PrepYou can use any kind of beans. I have used regular, unflavored kidney or red beans, vegetarian refried beans (they tended to mold) and cooked dried beans (trouble to prepare). Blend an equal volume of beans and water - 1 can of beans + 1 can of water until the mixture is smooth. Divide beans into two flasks. Add 8-10 drops of BEANO to one flask and no BEANO to the control flask. I incubated the flasks at 37oC overnight incubation to replicate what happens in the stomach. Once I added HCl to pH the beans to 2.0 - the pH they would be in the stomach. The next morning I buffered the beans back up to a 7.2 (the original pH) using a 1 molar sodium bicarbonate solution. I didn't see any significant difference in the results so it probably isn't worth the trouble. At the same time, I started an overnight culture of E. coli bacteria - I used MM 294 but most any lab strain of E. coli should do fine.You can use galactose and beta galactosidase as a positive control. Your students can develop any number of negative controls for this experiment. Teacher Tips Students will get a lot of gas production in their BEANO, beans and E.coli tubes and will immediately conclude that BEANO does not work. This is a good opportunity to teach the difference between in-vivo and in-vitro. The BEANO lab is an in-vitro (in glass) experiment. If BEANO were used in-vivo (in life), the enzyme breaks down the fibrous polysaccharides in beans which humans are normally unable to digest. The human then utilizes the sugars released and the intestinal bacteria don't get any extra nutrients. When BEANO is used in-vitro, the polysaccharides in beans are broken, releasing the sugars directly to E-coli bacteria in the test tube. They respond by going into an exponential growth phase and releasing a lot of gas. Intestinal Gas ReferencesBiotechnology Resources for Teachers , page 7, "Hey, Who Farted?" Massachusetts Biotechnology Research Institute, One Innovation Drive, Worcester, MA 01065.Science World , January 25, 1991, "The Bacteria Inside My Gut", p. 15-18. American Journal of Clinical Nutrition , Vol. 53, No. 3, March 1991, "Efficacy of an Oral Alpha-Galactosidase to Promote Oligosaccharide Hydrolysis and to reduce Intolerance Symptoms After Ingestion of Beans:A Dose-Response Trial, NW solomons, A-M Guerrero, E. Zepeda, C. Grazioso. p. 28. The Health Letter , SR:95-2, North American Syndicate, Inc. P.O. Bos 19622, Irvine, CT 92713. Issue devoted to management of intestinal gas. Health , October 1993. "Things Go Better With Beans", P. Jaret. p. 32-34. The Science Teacher , January 1994, "A Bio-Engineered Enzyme", Bullerwell, Raunig, & Hager. p. 27-20. AkPharma Inc, 6840 Old Egg Harbor Road, PO Box 111, Pleasantville, NJ 08232. BEANO Hotline: 1-800-257-8650. Whenever scientific experiments are done, it becomes very important to be able to quantify or measure your results. In order for this process not to be too gross, I have designed a test tube system to collect and measure the gas produced by E. coli as they break down beans. You should keep the following information in mind as you design your experiment. Be sure to use positive and negative controls in your experiment. Be sure to measure everything - the beans, the amount of E. coli culture, the amount of Beano, the length of time it takes to produce the gas and the amount of gas produced. You should prepare three test tube systems for each control and experimental test. You should develop a data collection chart before you begin this experiment.
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