Medicine: Save the Date
The resurrection of an ancient palm tree made headlines across the United States; for Hadassah researchers, it was one part of a project to revive Israel’s medicinal plants.
A burning sun slides toward a distant desert horizon. The relentless heat of yet another grim day is ending. Hungry, thirsty but still defiant, a defender of the besieged mountain fortress of Masada pulls a precious date from his pouch. He looks down on the Roman garrison camped implacably below, while he slowly chews the date’s sweet flesh, sucks its pit, then regretfully tosses it aside.
Or perhaps it was a woman who savored that ancient date as part of her diminishing daily ration, or a child she was trying to nourish. While we are unlikely ever to discover which of the 960 Zealots enjoyed the fruit, we’re about to learn a lot about the 2,000-year-old date itself.
That ancient date pit, excavated at Masada in 1973 and planted last January 25, Tu B’Shvat (the New Year for Trees), at Kibbutz Ketura, has been coaxed back to life.
Nine months after it was planted in the Negev, it stands 36 inches high and boasts nine healthy green leaves. The remarkable science that awakened the seed is that of renowned horticulturalist Elaine Solowey of Ketura, the kibbutz founded by Young Judaea the same year the pit was found. But the project itself, surprisingly, is that of the Hadassah–Hebrew University Medical Center at Ein Kerem.
“The Judean date was known throughout the ancient world, both for its succulence and for its important medicinal properties,” says British-born Dr. Sarah Sallon, director of Hadassah’s Louis L. Borick Natural Medicine Research Center, which she set up 10 years ago to study natural products and therapies. “Ancient Middle Eastern healing traditions used [the date] to treat many conditions, among them infections, tuberculosis, cancer, kidney disease and infertility.”
That date, however, had disappeared from history. The ones growing in Israel today are not the same as those that once covered the country.
“The Crusaders laid waste to the land, the Ottomans neglected it and the Judean date vanished,” explains Dr. Sallon. “When the Zionist pioneers returned in the late 19th century, they reintroduced date cultivation with dates from Iraq, Morocco and Egypt, many of them by way of California. Medicinal qualities possessed by the Judean date may have been specific to its particular genotype, and have thus been lost.”
Israel once had a reputation for greening the deserts and reclaiming the land, but those days are now only a memory, she says. Urbanization and development, conflict and climate change have consigned some 34 plant species to extinction in the past 40 years alone. A fifth of those that remain are on Israel’s list of rare and endangered species. As these plants vanish, treasure chests of natural products are lost to future generations.
It was Dr. Sallon’s interest in plant conservation and reintroduction that brought her and American-born Solowey together in a Hadassah partnership made in heaven. In 1998, they began a collaboration to domesticate indigenous plants that have potential medicinal uses. Solowey, who teaches agriculture and sustainable farming at the Arava Institute for Environmental Studies at Ketura, is a renowned plant scientist. She moved to Ketura four months after it was founded, when it had only 13 trees, all of them sick.
“I realized then that this was the place that needed me most,” she recalls.
The kibbutz has 9,000 healthy trees, 1,000 of them date palms planted by Solowey; she has “a personal relationship” with each, she says. After planting the trees, she “decided to see what else would grow,” she says. “I started out with biblical stuff—wheat, barley, pomegranates and figs. They’d grown here in the time of Abraham, and I reckoned there was a chance they’d grow now. They did. From there, I branched out into things that like the desert, and then on to subtropicals and root stocks. Some worked. Others, like the mango, couldn’t take the salt.”
Today, she has 25 acres of experimental plants at Ketura, growing over 100 different varieties, many of them domesticated for the first time in Israel, and several of them, such as the Moroccan Argania, for the first time anywhere.
She is also developing a seed bank with many important Israeli medicinal plants. Missing, however, was the Judean date.
“As far as we knew, it was extinct,” says Dr. Sallon. “Then we heard that Bar Ilan University was storing date pits found at Masada.”
Unearthed from level 34 of the Masada dig and identified by archaeologist Ehud Netzer, the pits were “sitting in a drawer in Bar Ilan’s botanical archaeology department,” says Dr. Sallon. “When I asked its director, Mordechai Kislev, if I could try and grow one, he said, ‘You’re mad!’ After some persuasion, he gave me three. I passed them on to Elaine.”
Solowey took them, though she “did not have much hope that any would come up.” To wake them, she first soaked the seeds in hot water to soften their coat, then in a hormone-rich acid and finally in an enzymatic fertilizer made from nutrients that included seaweed.
“I put the three seeds in new pots with new soil in a quarantined area, plugged them into drip irrigation and let them get on with it,” she says. “A month or so later, cracks appeared in the earth above one of the three. I phoned Sarah at once. ‘Something’s happening!’ I told her.”
With growing confidence, a date shoot pushed its way to the surface and unrolled two flat, pale, odd-looking leaves. The third and those that have followed, however, look like modern date leaves, although their pattern around the stem differs from the modern date palm. In the summer, at Dr. Sallon’s instigation, the University of Zurich radiocarbon-dated a sliver of the seed and gave its age as 1,990 years, plus or minus 50, placing it squarely at the time of the Roman siege of Masada.
“We were utterly elated!” says Dr. Sallon. “We’d heard of 1,200-year-old lotus seeds that sprouted in China, and 400-year-old seeds from London’s Natural History Museum that grew after the building was bombed in World War II and doused with water to put out the flames, but these Masada seeds were older by far.”
Cellular analysis of the seedling, performed at Israel’s Volcani Institute of Agricultural Research, shows differences in its DNA from that of the modern date, but with only one plant to test, no firm conclusions can be drawn. Kislev has parted with some more ancient date pits, and Solowey has begun awakening them as well.
Dr. Sallon’s interest in the therapeutic value of the Judean date was sparked by a unique project run by the center she directs (upgraded from a unit in June 2005, with the support of philanthropist Louis L. Borick).
Believing ancient remedies could be used to create modern medicines, in 1966 the center launched the Middle-Eastern Medicinal Plant Project (MEMP) to conserve, research and develop medicinal plants in Israel.
“The Judean date is one of hundreds of plants, shrubs and trees of this region—flora Palestina—with a history that goes back to the Bible,” says Dr. Sallon. “We hear about them through the psalms and the prophets, where almost every plant mentioned has extensive use in folk medicine, as well as in nutritional and ceremonial rituals—preparation of the Temple incense, the oil used in anointing…. We hear about such plants again in the Talmud and in the writings of Jewish and Arab physicians, such as Maimonides and Avicenna.”
MEMP’s unique database is drawn from the archive of the late David Zaichek of the Hebrew University of Jerusalem, who spent 30 years documenting medicinal plant use by Jewish and Arab healers. The database details the botany, ecology and use of some 500 medicinal species in different healing traditions along with a sophisticated cross-referencing system and search engine, which correlate traditional plant use with modern Western medicine.
“Plants have no borders,” says Dr. Sallon. “We hope to raise funds to put this treasure trove of ethno-botanical knowledge onto a Web site, a ‘plants-for-peace project’ for researchers throughout the Middle East.”
Despite the enormous variety and long historical tradition of flora Palestina, only a very small percentage of Israel’s 3,000 varieties have been scientifically studied.
“We favor a…focused approach in which we investigate different species guided by traditional knowledge of their use,” says Dr. Sallon. If, for example, a plant is traditionally used to treat infectious conditions, center researchers speculate it has antibacterial properties, and it is screened accordingly. Of 50 varieties so far tested for antibacterial effect in Hadassah’s Department of Clinical Microbiology, mainly by doctoral students, half have been found effective in treating infections—and a quarter very effective indeed.
For Borick researchers, plants described in Zaichek’s archive as tonics or cleansing agents are candidates for testing as immune system stimulants. The more costly testing of a plant’s impact on the immune system has been performed on two varieties from the artemesia and solenum genus.
“Indications are that in both there is a dual effect,” says Dr. Vivi Barak, director of Hadassah’s Immunology Laboratory for Tumor Diagnosis, who uses immune-system markers known as cytokines to evaluate activity. “They seem both to stimulate the immune system and have a significant effect on the inflammatory response. This could have important therapeutic indications for diseases that include arthritis, Crohn’s and multiple sclerosis.”
Artemesia may have another important application. Malaria was once endemic in Israel, and artemesia is among many local flora credited with antimalarial properties. A plant from the artemesia family, artemesia annua, has been used as a medicine in China and is the World Health Organization’s recommended drug against this worldwide killer.
Building the database and testing flora have led the Borick Center into domesticating and cultivating plants. “Almost all the medicinal plants listed are wild and many of them are now very rare,” says Dr. Sallon. “To provide a sustainable source of raw plant material for scientific testing, we have domesticated and conserved many of them, so that we don’t deplete Israel’s precious plant heritage.”
As well as trying to conserve these plants and integrate them into conventional medicine, the center is also aiming to reintroduce species that have become extinct in Israel. Dr. Sallon cites commiphora and boswellia, from whose sap fabled frankincense and myrrh were made.
According to legend, they have grown here since the Queen of Sheba gave seeds to King Solomon. Another example is opobalsumum, thought to be the source of Balm of Gilead. Brought from the Horn of Africa and the Persian Gulf states where these plants still grow, they are again being cultivated in Israel.
Germinating the 2,000-year-old date pit was a major achievement, but only the beginning, acknowledges Dr. Sallon. “We still have a long road ahead,” she says, “and one that we must fund entirely by ourselves. We don’t yet know if our first seedling is male or female. We hope it’s female, that we’ll have a male to pollinate it, and that it’ll live the four or five years it needs to produce fruit.
“Then, in this age of [genetically modified] foods, we’ll have a [historically unmodified] date,” she adds, “one with perhaps an interesting gene or two that has disappeared from the intensely cultivated modern date. If the long-lost genes that gave the ancient Judean date its reputation for healing can be propagated on a larger scale, we may have something really important—an old-new food with remarkable healing potential.”