Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New testing method hints at garlic's cancer-fighting potential

02.03.2010
Researchers have designed a urine test that can simultaneously measure the extent of a potential carcinogenic process and a marker of garlic consumption in humans.

In a small pilot study, the test suggested that the more garlic people consumed, the lower the levels of the potential carcinogenic process were.

The research is all about body processes associated with nitrogen-containing compounds, scientists say. These processes include nitrosation, or the conversion of some substances found in foods or contaminated water into carcinogens.

“What we were after was developing a method where we could measure in urine two different compounds, one related to the risk for cancer, and the other, which indicates the extent of consumption of garlic,” said Earl Harrison, Dean’s Distinguished Professor of Human Nutrition at Ohio State, an investigator in Ohio State University’s Comprehensive Cancer Center, and senior author of the study.

“Our results showed that those were inversely related to one another – meaning that the more we had the marker for garlic consumption, the less there was of the marker for the risk of cancer.”

Ultimately, the scientists hope to find that a nutritional intervention could be a way to stop the process that develops these carcinogens. This process is most commonly initiated by exposure to substances called nitrates from certain processed meats or high-heat food preparation practices, or to water contaminated by industry or agricultural runoff.

About 20 percent of nitrates that are consumed convert to nitrites. A cascade of events can convert these compounds into what are called nitrosamines, and many, but not all, nitrosamines are linked to cancer.

Vegetables also contain nitrates, but previous research has suggested that the vitamin C in vegetables lowers the risk that those nitrates will convert to something toxic. Researchers suspected that nutrients in garlic could have similar antioxidant effects as vitamin C.

The study is published in a recent issue of the journal Analytical Biochemistry.

The research began with the small human study based at Penn State University. Researchers there fed participants a weeklong diet lacking any nitrates or garlic. They then gave the participants a dose of sodium nitrate – in a formulation that would not become toxic, but which would show a marker in the urine of the potentially toxic process.

Groups were then treated with capsules containing varying levels of garlic: 1, 3 or 5 grams of fresh garlic, or 3 grams of an aged garlic extract. A separate group received 500 milligrams of ascorbic acid, or vitamin C. Both the nitrate formula and treatments were given for seven days. Urine samples were collected from all of the participants every other day for seven days.

That research team then turned to Harrison and colleagues, who explored the methods required to precisely quantify biomarkers in urine for both the garlic consumption and the presence of nitrosoproline, the indicator that nitrosation has occurred.

Harrison’s group developed the urine test using a method called gas chromatography-mass spectrometry.

Gas chromatography separates components of a mixture to detect specific substances, and has been used previously to quantify nitrosoproline. The addition of mass spectrometry to the analysis allowed for determination of the chemical structures of molecules in the sample – in this case, the presence of a specific compound that is released in urine after garlic is eaten.

When the test was used on the urine samples from the pilot garlic study, it showed that the participants who had taken garlic had lower concentrations of the marker for nitrosation than did those who took no garlic. Though the differences were slight, the consumption of 5 grams of garlic per day was associated with the lowest level of the marker for potential carcinogens. A single garlic clove typically can weigh between 1 and 5 grams.

Vitamin C had a similar effect in lowering the marker for nitrosation.

Harrison, also an investigator in the Center for Advanced Functional Foods Research and Entrepreneurship at the Ohio Agricultural Research and Development Center, noted that previous research has suggested that garlic and other plants with sulfur-containing compounds offer a variety of potential health benefits. Many questions remain about exactly what those benefits are and precisely how garlic works as a nutritional intervention.

“The precise mechanism by which garlic and other compounds affect nitrosation is under extensive investigation, but is not clear at this time,” he said.

“What this research does suggest, however, is that garlic may play some role in inhibiting formation of these nitrogen-based toxic substances. This was very small pilot study, so it’s also possible that the more garlic you have, the better it would be.

“So if you like garlic and you like garlic-containing foods, go out and have as much as you want. There’s no indication it’s going to hurt you, and it may well help you.”

The research was supported by grants from the National Institutes of Health and an Interagency Cooperative Agreement between the National Cancer Institute and the U.S. Department of Agriculture.

Harrison co-authored the study with former colleagues from the U.S. Department of Agriculture’s Human Nutrition Research Center in Beltsville, Md., including Keary Cope, a postdoctoral fellow, and Rebecca Seifried, a student, as well as Harold Siefried, John Milner and Penny Kris-Etherton. Harold Seifried and Milner are in the Nutritional Science Research Group in the National Cancer Institute’s Division of Cancer Prevention. Kris-Etherton and Milner conducted the human feeding study as faculty members at Penn State University.

Contact: Earl Harrison, (614) 292-8189; harrison.304@osu.edu
Written by Emily Caldwell, (614) 292-8310; caldwell.151@osu.edu

Earl Harrison | EurekAlert!
Further information:
http://www.osu.edu

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>