title: Validation of caffeine dehydrogenase from Pseudomonas sp. strain CBB1 as a suitable enzyme for a rapid caffeine detection and potential diagnostic test.
abstract: Excess consumption of caffeine (>400 mg/day/adult) can lead to adverse health effects. Recent introduction of caffeinated products (gums, jelly beans, energy drinks) might lead to excessive consumption, especially among children and nursing mothers, hence attracting the Food and Drug Administration's attention and product withdrawals. An "in-home" test will aid vigilant consumers in detecting caffeine in beverages and milk easily and quickly, thereby restricting its consumption. Known diagnostic methods lack speed and sensitivity. We report a caffeine dehydrogenase (Cdh)-based test which is highly sensitive (1-5 ppm) and detects caffeine in beverages and mother's milk in 1 min. Other components in these complex test samples do not interfere with the detection. Caffeine-dependent reduction of the dye iodonitrotetrazolium chloride results in shades of pink proportional to the levels in test samples. This test also estimates caffeine levels in pharmaceuticals, comparable to high-performance liquid chromatography. The Cdh-based test is the first with the desired attributes of a rapid and robust caffeine diagnostic kit.
authors.affiliation: Department of Chemical and Biochemical Engineering, University of Iowa , 4133 Seamans Center, Iowa City, Iowa 52242, United States.
authors.forename: Sujit K
authors.initials: SK
authors.lastname: Mohanty
authors.forename: Chi Li
authors.initials: CL
authors.lastname: Yu
authors.forename: Sridhar
authors.initials: S
authors.lastname: Gopishetty
authors.forename: Mani
authors.initials: M
authors.lastname: Subramanian
mesh_terms: D001426:Bacterial Proteins; D001628:Beverages / Q000032:analysis*; D002110:Caffeine / Q000032:analysis*; D005504:Food Analysis / Q000379:methods*; D006801:Humans; D007202:Indicators and Reagents; D008895:Milk, Human / Q000737:chemistry*; D010088:Oxidoreductases; D004364:Pharmaceutical Preparations / Q000737:chemistry; D011549:Pseudomonas / Q000201:enzymology*; D012680:Sensitivity and Specificity; D013053:Spectrophotometry; D013778:Tetrazolium Salts
chemical_list: D001426:Bacterial Proteins; D007202:Indicators and Reagents; D004364:Pharmaceutical Preparations; D013778:Tetrazolium Salts; C013574:iodonitrotetrazolium; D002110:Caffeine; D010088:Oxidoreductases; C000595922:caffeine:ubiquinone oxidoreductase, Pseudomonas