Mary Stucky, Contributing Writer

Long before the drug Viagra, Indians in Peru had their own libido enhancer -- an unassuming root called maca.

Slideshow: Peru's 'Natural Viagra'

Maca caught the attention of a U.S. company, which got a patent on this so-called natural Viagra. And just a few months ago, Wal-Mart started selling the tonic.

But Peru is crying foul, claiming maca was stolen from the people who knew about it first.

Maca is sold everywhere in the Peruvian Andes. In the town of Junin, Ana Luna Derete and her husband, Vicente Fijueroa, sell products made of maca. With a twinkle in his eye, Fijueroa said, "Maca will make you strong."

Fijueroa sells the root itself, which looks something like a small brown stone. He also sells an alcoholic drink made of maca and the local aguardiente. If that's too strong, there's maca blended in fruit juice and water. And there's maca flour ground from the root. Fijueroa invites me to taste the flour, which is rather sweet and apparently also potent.

Six years ago, a New Jersey company got a U.S. patent on an extract of maca, called MacaPure. The company was later bought out by the French firm Naturex. Chris Kilham, a Naturex consultant and spokesman, said millions of dollars went into developing MacaPure.

"Nobody had ever previously discovered these two groups of compounds in maca called the macamides and macaenes," Killham said. "And nobody ever developed an extract that standardized those."

But many people in Peru say MacaPure is basically what's for sale in the market in Junin. Lawyers representing the Peruvian government say MacaPure is not a novel invention as required by U.S. patent law.

Begona Vernero is preparing a legal challenge to the patent.

"We don't see a contribution from these people who claim this patent," Vernero said. "No contribution at all. The only thing they've done is scientifically prove what Peruvians have done for ages."

Both sides agree on one thing: There's potentially a huge market for Peru's natural Viagra. Exports of maca have more than doubled in the past five years. The debate is over who profits.

Farmer Elvira Llanos dries maca seeds behind her storehouse, where bags of maca are stacked to the ceiling. Maca is a food staple in Junin, and this region is the only place maca grows. Llanos remembers how farmers in Junin reacted when they found out about the patent.

"There was an outcry from everyone," Llanos said. "And we asked, 'Why isn't there anyone helping the farmers and caring about the problems involved with this patent on maca?'"

But Kilham said the company is helping the farmers, creating a bigger market for maca and establishing community programs.

"I believe in the efforts we've made so far in terms of the free dental clinic and assisting with other community programs and projects," said Kilham. "I maintain that this is just the beginning."

Kilham said Naturex has no intention of enforcing its patent in Peru and will let Peruvian companies continue to sell maca extract. But many here said that's not enough. Environmental lawyer Manuel Ruiz said Peruvians should share in the MacaPure profits since it's based on their plants. But he's skeptical that will happen.

"There's a history, and that history has an impact on our reaction to these types of situations," said Ruiz. "If you look at malaria and the initial cure for malaria, it came from the quina tree, which is found in the Peruvian Amazon. And from that you've developed quinine-derived drugs. And people say those came originally from here, and what are we receiving from that?"

The 1992 Convention on Biological Diversity stipulates that nations are entitled to a share in the profits from products derived from their plants. For Peruvians, it's a matter of fairness. Natural Viagra was theirs for centuries, and if anyone gets rich from it, people in Peru say it should be them.

This article is provided by Round Earth Productions, an independent production company that reports on Latin American issues for radio, print and web distribution. Major funding for the project comes from the W.K.Kellogg Foundation. For more information please visit roundearthproductions.org.