Ancient people knew that some kinds of clay have healing qualities. They rubbed clay on their skin to cover wounds. They also used the natural rock or soil material to treat stomach problems.
Now, American researchers have discovered how different clays work as medicine. They are researching the effectiveness of clays against antibiotic-resistant infections.
Blue and green clays are found in volcanic areas of the world. Around volcanoes, native peoples used the clays to improve their health. It seems they knew what they were doing.
Lynda Williams is a clay and mineral scientist. She works at Arizona State University's School of Earth and Space Exploration in Tempe. She and her research team have been studying the Aboriginal people of Australia.
"There is evidence of Aboriginals using clays for treating wounds and they eat it. Many cultures eat clays to settle their stomach."
Williams and her team found the clay was effective against some pathogens. Pathogens are bacteria and viruses that cause disease. They examined bacteria that have developed resistance to other antibiotics.
In laboratory tests, they saw how a blue-colored clay is effective against the drug-resistant Staphylococcus aureus, known as MRSA. MRSA is a dangerous and sometimes deadly skin infection.
The clay was also effective in treating Buruli ulcer, a skin disease found in the Ivory Coast.
Here is how the blue clay works. Iron is one of the chemicals found in the clay. The bacteria need the iron to survive.
Some of these same clays also contain aluminum. The minerals work together. Lynda Williams says aluminum lets iron flood into harmful bacteria. The iron oxidizes and then kills the bacteria.
"In the end, what we found is that aluminum is attacking the proteins in the cell wall of the bacterium and allowing pores to open so that iron, reduced iron 2, goes into the interior of the bacterium, (and) has reactions with the protein inside. It becomes oxidized and it destroys the biomolecules inside the cell, killing the bacteria."
Williams says she hopes the study will interest drug companies that want to explore the healing properties of blue and green clays.
The National Science Foundation provided financial support for the study. Williams and her colleagues reported their findings in the journal Nature Scientific Reports.
I'm Anna Matteo.
1.antibiotic-resistant adj. 耐抗生素的
Another cause for concern for human health is the inappropriate use of antibiotics in poultry production, and the development of antibiotic-resistant strains of bacteria.
2.aboriginal people 土著民
Most Canadians acknowledge that the aboriginal people have had a rotten deal.
3.pathogen n. 病原体；病菌
The pathogen was almost instantly detected by automated systems.
4.oxidize vt. 使氧化；使生锈 vi. 氧化
If the organic material decays or is oxidized, it will not form petroleum.
5.biomolecule n. 生物分子
However, biomaterial and biomolecule interaction mechanism is far from being thoroughly understood in an atomic and electronic level.
1.They examined bacteria that have developed resistance to other antibiotics.
resistance to 对……的抵抗
Alcohol lessens resistance to diseases.
Generally speaking there was no resistance to the idea.
2.In laboratory tests, they saw how a blue-colored clay is effective against the drug-resistant Staphylococcus aureus, known as MRSA.
The medicine is effective against cancer.
Simple antibiotics are effective against this organism.