Yucca

Scientific Name(S): Yucca spp. Family: Agavaceae

Common Name(S): Yucca, Spanish bayonet, Our Lord's candle, Joshua tree, Adam's needle

Botany

The name yucca applies to as many as 40 species of trees and shrubs found mostly in arid portions of North America. The common names noted above can apply to different species. The Spanish bayonet is Y. aloifolia and Our Lord's candle is Y. whipplei. Other common yuccas include Y. schidigera (Mohave yucca) and Y. brevifolia (Joshua tree), which grows to 60 feet in height and is commonly found at the bases of desert mountains. Yucca plants are characterized by stiff, evergreen, sword-shaped leaves crowded on a stout trunk. There is a dense terminal flowerhead (panicle) faintly resembling a candle. The flowers are white or greenish. All yucca plants depend for pollination on nocturnal yucca moths (Tegeticula). Each variety of moth is adapted to a single species of yucca.

Uses

Yucca has been historically used as a fiber, soap, and for consumable products. Some evidence suggests the extract may be effective in the management of arthritis, hypertension, and hypercholesterolemia.

Side Effects

History

Yucca plants have served American Indians for centuries for a variety of uses including fiber for rope, sandals and cloth; the roots have been used in soap. The Indians and early Californian settlers used the green pods for food. Indian uses included boiling and baking the fruits, eating the blossoms, chewing the raw leaves and fermenting the fruits to produce a beverage for high rituals. In modern times yucca has been used in soaps, shampoos and food supplements. Yuccas contain saponins that have a long-lasting soaping action. The plant has been purported to be beneficial for treating hypertension, arthritis, migraine headaches, colitis, and a variety of other disorders. A solid extract is derived from the leaves; the Mohave yucca is the most common commercially used plant. Current commercial uses of yucca extracts include foaming agents in carbonated beverages, flavorings, and for use in drug synthesis research.

Chemistry

The roots of the yucca contain saponin glycosides consisting of a sapogenin and a sugar. Saponins are characterized by their bitter taste and their ability to foam when shaken with water. Most species of Yucca contain sarsasapogenin and tigogenin. Cortical cells in the roots of Y. torreyi have been found to contain microbodies containing crystalline nucleoid inclusions that have been identified as unspecialized peroxisomes. Y. aloifolia leaves contain up to 1.4% tigogenin and this compound can be used as a starting point in the commercial synthesis of steroidal hormones.

Summary

Yucca is a hardy plant native to arid areas of North America. It has long been used for a variety of purposes, including as a fiber, soap, and for consumable products. When taken orally, it appears to be relatively nontoxic. While some evidence suggests the extract may be effective in the management of arthritis, hypertension, and hypercholesterolemia, there is no published corroborative evidence. Extracts may have potential as antiviral agents.