Since ancient times, people have used propolis to control bacteria, fungi, and viruses. Now U researchers are looking for ways to use it to combat AIDS.
Beauty in the hive of the beholder
U researchers tap bees to help crops and fight AIDS
By Deane Morrison
Published on September 1, 2005
What with making honey and beeswax and pollinating our crops, bees are already doing their share for humanity. But add one more item to their resume: They collect a plant resin, called propolis, which inhibits the growth of the AIDS virus in laboratory cultures.
University of Minnesota researchers are in the thick of efforts to tap its potential as a source of a new anti-HIV drug. Between 9 a.m. and 6 p.m. Friday, September 2, University bee researcher Marla Spivak and graduate students will be on hand at the U of M building at the state fair to talk about bees and propolis.
Since ancient times, people have used propolis to control bacteria, infectious yeast, fungi, and viruses. "It's a resin from particular trees--birch, poplar, some conifers," says Spivak. "Bees pick it up on their back legs." It's quite gummy, and bees find it perfect for sealing their hives. They also use it to line the entries to hives, a habit that gives propolis its name, which means "before the city." Thanks to propolis, beehives are one of the most sterile environments on Earth.
University researchers Phil Peterson and Genya Gekkar of the Medical School have found evidence that propolis inhibits HIV infection in the laboratory cultures of the white blood cells targeted by the virus. But so far, it isn't known just which components of the plant resins in propolis carry anti-HIV properties. Identifying the chemical structure of the active component in propolis (once it's isolated) and developing a means of synthesizing it is the goal of Ramaiah Muthyala, senior associate director of the University's Center for Drug Design.
Not all propolis is created equally, however. Recognizing the variability in trees and bees, postdoctoral researcher Lana Barkawi, working in horticultural science professor Jerry Cohen's lab, is testing propolis from around the world. Some of the strongest anti-HIV activity has turned up in propolis from southeastern and northern Minnesota and from China.
For her part, Spivak and her colleagues are studying how propolis affects bee health and the biology of propolis collection by bees. "Our ultimate goal is to protect and propagate healthy honey bees to ensure we have sufficient pollinators for our fruits, vegetables, and flowers," she says.
Besides her work with propolis, Spivak has been breeding honey bees for resistance to disease and parasitic mites. The damage from bee diseases and mites has serious implications for crops, because a third of our diet depends directly or indirectly on bee pollination, she says. For example, this year's California almond crop was down 11 percent from 2004 due to a bee shortage brought on largely by a mite infestation. To fight this parasite, Spivak has bred a "MN Hygienic Line" of bees that can detect the presence of mites in bee pupae and "throw out" infected pupae. This February, about half the commercial hives in California collapsed from the mites because the parasites had developed resistance to chemical means of control. But, says Spivak, beekeepers around the country who used the "hygienic" bees did all right wherever they went.
At the fair, Spivak will display a beehive with live bees, honey products, and a propolis-trapping grate used to collect the substance in large quantities.