Tea fights bad breath
Compounds found in tea can stop the growth of bacteria that cause bad breath, according to researchers at the University of Illinois at Chicago.
Polyphenols, chemical components of tea, prevent both the growth of bacteria responsible for bad breath and the bacteria’s production of malodorous compounds, the UIC researchers found. The findings were presented today at the annual meeting of the American Society for Microbiology in Washington, D.C. by Christine Wu, professor of periodontics and associate dean for research at the UIC College of Dentistry, and research associate Min Zhu.
Bad breath -- or halitosis -- afflicts a large portion of the population. It is caused by foul-smelling volatile sulfur compounds, like hydrogen sulfide, produced by anaerobic bacteria that thrive in environments lacking oxygen, such as the back of the tongue and deep gum pockets.
In the laboratory study, Wu and Zhu incubated tea polyphenols with three species of bacteria associated with bad breath for 48 hours.
At concentrations ranging from 16 to 250 micrograms per milliliter, the polyphenols inhibited growth of the oral bacteria.
At even lower concentrations -- from 2.5 to 25 micrograms per milliliter -- the polyphenols hindered the enzyme that catalyzes the formation of hydrogen sulfide, cutting its production by 30 percent.
Wu said the present study complements earlier research in her laboratory showing that black tea suppresses the growth of bacteria in dental plaque and that rinsing with black tea reduces plaque formation and the production of acids that cause tooth decay.
"Besides inhibiting the growth of pathogens in the mouth, black tea and its polyphenols may benefit human oral health by suppressing the bad-smelling compounds that these pathogens produce," Wu said.
The polyphenols found in tea include chemicals called catechins and theaflavins. Catechins are found in both green and black teas, while theaflavins are found predominantly in black tea.
Black tea, an aqueous infusion of dried leaves of the Camellia sinensis plant, is the most popular beverage worldwide, second only to water. Per capita consumption averages four fluid ounces per day.
Sharon Butler | EurekAlert!
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
New technique promises tunable laser devices
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...