Grant will assist pharmacy students in search for prescription-drug ingredients

The National Institute of Health and the National Science Foundation renewed funding for the project Oct. 1, after supplying about $2.5 million the past five years. The research will help develop prescription medicine to treat various health problems.

"We receive the money; everything is done from here. It's good for UA publicity and gets us on the map," said Barbara Timmermann, a pharmacology and toxicology professor. "There is a lot of competition out there."

Timmermann is the principal investigator of the project, which takes about 45 undergraduates, graduates and professors to Argentina, Chile and Mexico to study plants and derive medicinal elements.

The project, "Bioactive Agents from Dryland Biodiversity of Latin America," was extended for an additional five years to include the study of microorganisms as well as plant fauna.

"From 1993 to 1998 we were looking for prescription drugs or medicine in plants from arid and semiarid areas in Argentina, Chile and Mexico," Timmermann said. "Now, in addition to plants, we're looking for drugs in microorganisms on plants."

Microorganisms - also called microbes - are disease-causing bacteria, mold or fungi that grow on plants. University of Arizona scientists are looking for microbes that can be used to make prescription drugs.

The microbes are antibiotic sources that can help treat transplant and cancer patients.

"The drug taxtol, which is made from the pacific yew tree, is used to treat breast and ovarian cancer," Timmermann said.

She said Hodgkin's disease and childhood leukemia are treated with velban, which is extracted from the rosy periwinkle plant.

Other prescription drugs are designed to treat the central nervous system, cardiovascular system, allergies and inflammation. The team is also researching women's health issues, such as osteoporosis.

The microorganism are also a source of penicillin, which can be used to prevent and treat certain diseases. The new drugs may help people who have developed immunity to some antibiotics. For example, tuberculosis is growing more resistant to antibiotics.

Staff in the College of Pharmacy's Natural Products Lab search for isolated compounds in plants with medicinal benefits.

"The isolation of compounds are responsible for different biological activities," Timmermann said. "We do this by using state-of-the-art chemical techniques."

Gerald Waechter, a research associate, said the lab receives a few hundred samples, measured at 1 kilogram each, which are used to extract organic solvents.

He said solvent extraction is similar to brewing tea. The solvent is poured into a filter that leaves a solution of plant chemicals. The extract looks like a similar to a "green sticky material," Waechter said.

The extract is then sent to pharmaceutical companies for testing, after which the UA lab conducts more chromatography tests. It is sent again to a pharmaceutical company and returned to the UA as a pure compound. After a battery of testing, scientists decide whether to develop the drug.

The project's long-term goal is to search plants and microbes for organisms that can be used in prescription drugs and approved by the Food and Drug Administration as safe and effective, Timmermann said.

She said besides looking for plants in the common desert, searching for plants in the rain forest will be a new challenge.

"It's going to be fun this time," Timmermann said.

Irene Hsiao can be reached via e-mail at Irene.Hsiao@wildcat.arizona.edu.