Mucilaginous plants and their uses in medicine

245

of Ethnophannacology, 29 (1990) 245-266 Elsevier Scientific Publishers Ireland Ltd.

Journul

Review Paper

MUCILAGINOUS

PLANTS

AND THEIR

USES

IN MEDICINE

J.F. MORTON Morton Collectanea,

University

of Miami P.O.

Box 8204, Coral Gables,

Florida

K%S.A.I

Summary Throughout the world but especially in the tropical and subtropical zones, there are succulent and non-succulent plants which harbor readily releasable mucilage in their tissues, on the surface of their seeds or in their bark. This mucilage may have diverse practical uses. Among these, it functions as a healing agent, casually or in the practice of traditional-folk or conventional medicine. The mucilage of some of these plants is well known to science and has been studied by pharmacologists and found to possess biologically active principles. However, they all have in common a beneficial effect on burns, wounds, ulcers, external and internal inflammations and irritations, diarrhea and dysentery. This paper presents examples of such plants belonging to 19 botanical families, with a view to calling attention to the similar uses of easily extracted plant mucilages and, particularly, their ability to provide protection from fire, a feature which has already been demonstrated in Australia.

Introduction

Gums and mucilages derived from higher plants and fungi, or produced synthetically, are much employed in food-processing, pharmaceutical and other industries. Outstanding examples of those used as demulcents in standard medical practice are: gum tragacanth (from several species of Astrugubs), flaxseed U&urn usitatissimum L.), gum arabic (Acacia Senegal (L.) Willd.) and psyllium seed (from several species of PsyZZium) (Morton, 1977; Swinyard and Pathak, 1980; Tyler et al., 1981). Technically, gums and mucilages are lumped into a single category, gums, with two subdivisions based on “tackiness” and “sliminess”. The latter, mucilaginous gums or simply mucilages, are the more easily obtained from plants and more commonly utilized in informal healing, other folkways and domestic food preparation. They are all mixtures of polysaccharides of high molecular weight (Whistler and BeMiller, 1973). 0378-8741/90/$08.05 01990 Elsevier Scientific Publishers Ireland Ltd. Published and Printed in Ireland

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Some mucilaginous plants are now known to possess biologically active principles, for example, the cytotoxic bufadienolide, Bryophyllin B, isolated from ~u~~c~oe ~~~t~ Pers. (Yamagishi et al., 19891.Yet the popular Aloe veru fL.1 Burm. f.), seemingly with even greater healing ability, and with confirmed antibiotic activity (Lorenzetti et al., 19801, has frustrated those who have sought its “miracle ingredient”. It is time to consider mucilaginous plants with similar uses and to confront the possibility that water-rich plant mucilages with high polysaccharide content may be very protective of normal cells - stimulating regeneration when attacked - whether or not there are identifiable agents present that may have supportive action. Methodology The purpose of this paper is to present a more or less random selection of plants that serve to illustrate the common use of mucilages for folk and conventional healing, as well as for casual prevention of injury. The notes are arranged alphabetically by plant family Bombacaceae, Cactaceae, Lauraceae, Commelinaeeae, Crassulaeeae, Cruciferae, Labiatae, Le~minosae, Liliaeeae, Malvaceae, Orchidaceae, Pedaliaceae, Plantaginaceae, Rosaceae, Schisandraceae, Scrophulariaceae, Tiliaceae, Ulmaceae and Vitaceae. Only brief details of plant description, origin, geographical range, mucilaginous parts and medical or other uses are given. These are derived from the literature in the botanical subject files and in reference texts of the Morton Collectanea, a research and information center of the University of Miami, and the personal observations of the author. Some botanical sources of mucilage BOMBACACEAE Adamonk digitata L. Baobab A striking tree to 20 m high, it has an enormous trunk attaining a diameter of 8 m or more. The alternate leaves have 3-7 leaflets 8- 15 cm long. Individual flowers, white, with recurved petals and a showy mass of stamens, hang on long stalks. The woody, velvet-covered fruit, to 30 cm long, contains a dry but edible dream-of-tartar-like substance and hard, kidneyshaped seeds. The tree, a native of tropical Africa, is cultivated in India and is grown as a curiosity in the West Indies and southern Florida. The bark and the leaves release much mucilage. The leaves are applied to inflamed swellings and sores. The leaf infusion is prescribed in earache, ophthalmia and various other in~ammations, and given as an expectorant and demuleent in diarrhea, respiratory and digestive disorders and fevers (Dalziel, 1948; Watt and Breyer-Brandwijk, 19621.

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The mucilage from baobab leaves is a complex macromolecule composed of polysaccharide, protein and minerals; it also contains non-carbohydrate components in unusually high concentrations. It is also unusual in possessing equal amounts of galacturonic and glucuronic acids. In this respect it differs from okra mucilage, (Woolfe et al., 1977). The bark mucilage is bitter, therefore it is also valued in treating fever. In fact, it has been widely marketed as a substitute for quinine (Watt and Breyer-Brandwijk, 19621. All parts of the tree have many uses. The leaves are sold fresh or dried and reduced to a powder, which is employed in soup and as a mucilaginous condiment. Fresh leaves without hairy foliage are marketed and commonly eaten after boiling. Though high in protein and calcium, the leaves contain tannin and other elements that prevent the system’s full use of nutrients. They are of low digestibility and provide mainly roughage (Andy and Eka, 1985). CACTACEAE Hylocereus

undatus Brit. et Rose. Night-blooming cereus or strawberry pear A climbing cactus, it has thick, jointed, three-angled stems with wavy margins; the areoles bear l-3 spines, 2-4 mm long. Highly fragrant white flowers, to 30 cm long, open at night. The edible fruit, coated with overlapping, leaf-like scales, is red, oval, lo-12 cm long, 7.5 cm wide, and filled with white, juicy, sweet flesh and minute black seeds. Believed native to southern Mexico, this much-admired cactus is commonly cultivated and naturalized throughout Central America, tropical South America, the West Indies and southern Florida, and has been introduced into Hawaii and other warm regions. In Yucatan, the mucilaginous pulp of the stem is applied as an emollient poultice on inflammations (Lavadores Villanueva, 1969). Salvadorean physicians similarly employ the cooked and mashed leaves of Epiphyllum phyllanthus Haw. (syn.: Cereus phyllanthus DC.1 which are rich in mucilage (Guzman, 1947). In Curacao, the giant tree-like cactus, Cereus repandus Mill., with many erect branches, is the source of a popular mucilaginous soup. After the thorns are removed from one of the spiny, 7--&ribbed branches, the outer, waxy “skin” is peeled off, then the thin layer of green pulp is removed and sun-dried and pounded to a powder. Boiling results in a product much like strained okra (Morton. 1967). Nopalea cochenillifera

(L.) Salm-Dyck. Cochineal cactus This is a much-branched, erect plant, to 4 m high, with short trunk and numerous, nearly spineless, oblong, thin joints and red flowers and fruit. Of unknown origin, it is believed to be native to southern Mexico as it has long been cultivated there. It has been introduced into many warm areas of the world as a host of the cochineal insect from which the well-known red dye

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was derived. The mucilaginous joints are split open and applied as a poultice to relieve burns, skin diseases, earache and toothache (Anon, 19661, as well as inflammations of various sorts; they are placed over the liver area to allay discomfort of that organ (Williams and Williams, 19511. Opuntiu ficus-indica

Mill. Indian fig, tuna, spineless prickly pear A succulent cactus, it grows to 4 m high, with a short trunk that becomes woody with age. Its flat branches (joints) are elliptic or oblong, 30-60 cm in length and about 8 cm wide, mostly without spines; sometimes with short yellow bristles (glochidsl clustered on the areoles but these soon drop aff (Standley, 19241. The flowers are yellow and the fruits red, 5-9 cm long, juicy and edible despite the abundance of minute black seeds. Native to tropical America, it was introduced to California by Spanish missionaries; by 1570 it was growing in Italy and by 1764 it became naturalized and was very common in the Mediterranean region (Font Quer, 1975). The joints contain much mucilage, which is widely utilized as an emollient and resolutive. They are often split open and heated in an oven or merely soaked in water and then employed as a poultice, especially on painful swellings and wounds. (Guzman, 1947; Font Quer, 19731. A Cuban gentleman in Miami stated that he witnessed the healing of a radiation therapy burn by leaving the fleshy side of a sliced-open cactus joint on the affected area overnight (personal communication). The peeled joint, mashed and mixed with almond or coconut oil, is applied over the liver area when that organ is painful. The chopped pulp is steeped in water overnight or for a day and the infusion spread on the face to remove blemishes, or drunk to halt diarrhea. The sweetened infusion is prescribed to relieve other intestinal complaints and chest conditions (Pompa, 19741. The mucilage extracted from the plant by pressure, or soaking in water, or by boiling, resembles gum tragacanth. It is almost insoluble in water but swells to a jelly-like mass which acts as an adhesive (Anon, 19661. An infusion of the pulp of the joint is applied to the scalp to promote the growth of hair (Nufiez Melendez, 19751. A shampoo is being manufactured of the pulp in Jamaica. At present, “Skin Care Cactus Products” are being advertised on the United States television. Rhipsalis

baccifera (Soland. ex J. Mill.) Stearn (syn.: R. cassutha Gaertn.) Mistletoe cactus, disciplinilla A succulent plant, epiphytic on trees and cliffs. It has numerous, pendent stems to 10 m long and cylindrical branches set with bristly aeroles when young. The small white, yellowish or pinkish, seedy fruits are very mucilaginous. This curious cactus occurs wild in eastern Mexico, Central America, South America and the West Indies as well as in tropical Africa and Sri Lanka. It is rare in southern Florida, where it grows among mangroves and buttonwood trees (Standley and Williams, 1962; Long and LakeIa, 19711.

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The mashed plant, which is very mucilaginous, is employed as an emollient poultice (Roig y Mesa, 19451 to overcome skin irritations and as a shampoo to stimulate the growth of hair and to stop it from falling (Pompa, 19741. COMMELINACEAE Commelina eleguns HBK. Larger dayflower, canutillo A succulent, semi-reclining plant, its stems reach 30- 100 cm in length. The leaves are 3-5 cm wide and to 10 cm long, pointed, with the sheaths and spathes bearing long white hairs. The flowers are pale-blue or white. The seeds are nearly round and smooth. This spreading plant grows wild in the southeastern United States, Bermuda, the Bahamas, the West Indies, Central America and southern Mexico. In Cuba, the plant decoction, regarded as diuretic and emollient, is drunk to relieve any kidney or bladder irritation and intestinal inflammations (Roig y Mesa, 19451. Commelina

erecta

L. (including C. erecta var. angustifolia (Michx.1 Fern.). Narrow-leaved dayflower A perennial, succulent herb, with a tuft of erect or reclining, slender stems radiating from a crown of thick, black, hairy roots. The leaves are lanceolate to ovate or elliptic, 5-15 cm long, 3-10 mm wide. The sheaths are hairy; the flowers 16-25 mm across, with two large blue and one small white petals. The capsule contains five small, black seeds. This species grows wild in pine lands, dry woods, white sandy scrub and rocky fields along the coastal plain of North America from North Carolina to southern Florida and west to Texas; it also grows in the West Indies. The botanist John K. Small commented that “The mucilaginous sap is used by the Seminoles to soothe irritations” (Small, 1933). They doubtless needed it badly because of the plentiful mosquitoes in the Everglades, as well as the toxic saps of poison ivy, poisonwood and manchineel. CRASSULACEAE Kdunchoe

pinnata (Lam.1 Pers. (syn.: Bryophyllum pinnatum (Lam.) Kurz.). Life plant, leaf-of-life, air plant This is a succulent, erect herb, to 1 m tall, with opposite, fleshy, ovate leaves with scalloped margins: the upper leaves often pinnate with three leaflets to 7.5 cm long, the lower leaves simple. There are showy terminal panicles of pendent blooms, whose reddish, bell-shaped corolla protrudes from a cylindrical, tubular, green or purplish calyx. Supposedly native to the Moluccas, Madagascar and Mauritius, this fastmultiplying plant has become naturalized throughout the tropics of both hemispheres and in southern Florida.

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Heated leaves are placed on insect bites (Dastur, 1952?1, wounds, ulcers, abscesses and burns (Dalziel, 19481.In Guam and Ghana, warmed leaves are applied to inflammations and wounds (Boakye-Yiadom, 19771; Safford, 19051. Swellings and discolorations are claimed to be prevented or reduced; while wounds are healed quickly (Dastur, 1952?1. After heating and blending with oil, the leaves are rubbed on rheumatic affections, erysipelas and boils (Quisumbing, 19511.The leaf decoction is applied on mange and is given as a cold remedy, especially to small children (Walker and Sillans, 1961). In west tropical Africa, the leaf juice is fed into a newborn infant’s mouth, while an infusion is drunk by the child and the mother (Dalziel, 19481.Nigerians use the juice as a treatment for conjunctivitis and earache, and as a lather for shaving the head. They also take it internally as a diuretic; this activity is attributed to its potassium mallate content (Oliver, 19601. In Singapore, the juice is given as a febrifuge (Burkill, 19351.Manfred (1947) claims that in the morning the leaves are acid in flavor; at noon, tasteless; at night, very bitter. Studies at the Faculty of Pharmacy, University of Science and Technology, Kumasi, Ghana, showed that the juice expressed from warmed leaves has antibiotic activity against Staphylococcus aureus, Bacillus subtilis, Escherichiu coli and Pseudomonas aeruginosa (Boakye-Yiadom, 19771. Gaind and Gupta (19711 reported the presence of three glycosides in pulverized leaves: glycoside A (not defined); glycoside B (characterized as quercetin 3diarabinosideh and glycoside C (kaempferol 3-glucosidel. Yamagishi and coworkers (1989) found in a water extract of the whole plant collected in Tapei, Taiwan, a potent cytotoxic bufadienolide which they named Bryophyllin B. The flowers contain a honey-like substance and in Argentina a decoction is given in all cases of colds and bronchitis (Manfred, 19471. CRUCIFERAE Lepidium sativum L. Garden cress This plant is a strong-scented, bushy, annual herb, 15-45 cm high; the leaves varying from entire and linear to more or less deeply divided. The small white flowers are borne in long or short racemes. The seedpods are nearly round and winged; the seeds 3 mm long, 1.3 mm wide, maroon, minutely netted. Believed to be native to East Africa and possibly western Asia and Europe, garden cress is widely grown as a salad herb and fodder plant. The seeds are commonly sold in Indian markets under the name halim (Datta and Datta, 1961). They yield a mucilage containing 18.3% cellulose and a complex of polysaccharides. It is taken to soothe intestinal irritation which causes diarrhea and dysentery (Anon, 19621. Sipped frequently, it will overcome hiccup (Dastur, 1952?1.

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LABIATAE Hyptis suaveolens

Poit. Wild spikenard An erect, annual, bushy herb to 2 m high, it has quadrangular, hairy stems. The leaves are thin, broadly ovate, opposite, aromatic, 3 - 10 cm long; toothed and minutely downy above and beneath. The flowers are purple or white and borne in terminal clusters, and the nutlets tan, ribbed, 3-4 mm long. A native of Mexico, Central and South America, the West Indies and Bahamas, it is now a widely introduced weed in the Old World tropics. While the plant is commonly employed as an herb tea, an antiseptic poultice and a mosquito repellent, the seeds are valued for their abundant mucilage which is released on soaking in water. The strained infusion is taken as a cooling drink, sharing the name chiu with other similar plant beverages (Standley and Williams, 19731. It is considered to alleviate intestinal afflictions (Martinez, 19591.

Lallemantia

royleana Benth. Balangoo-shirazi This is an annual herb, hairy or nearly smooth, 15-45 cm in height. The leaves are oblong to ovate, bluntly toothed, 2 - 5 cm long. The tiny, lavender flowers are borne in whorls on long spikes and are followed by smooth, black seeds 3 mm long and 1 mm wide, with a white dot at the end. The plant grows wild plentifully in Iran, Afghanistan, Turkestan, Pakistan and northern India up to 900 m altitude. It is cultivated, at least in India and Iran, for its seeds; these are sometimes used to adulterate black psyllium but are hazardous and apt to cause bowel obstructions (Anon, 19621. When soaked in water, the seeds instantly become coated with opaque, gray, tasteless mucilage. A popular drink prepared from them is taken to relieve coughs and urinary irritations. The seeds are formed into poultices for boils, abscesses and various inflammations (Chopra et al., 1958; Parsa, 19601. O&mum basilicurn L. Sweet basil

This is an erect, pleasantly aromatic, annual herb or subshrub, to 1.5 m high. The leaves are ovate, to 3 cm long, sometimes faintly toothed. The flowers are white or pink and borne in erect racemes to 15 cm tall. Native to India and Iran, southern Asia and East Africa (Hooper and Field, 19371, sweet basil is grown in all warm climates as a condiment, fresh or dried, and much employed in folk medicine. It is also valued in tropical dooryard gardens as an insect repellent. The seeds are coated with mucilage and are applied as a poultice on sores (Dastur, 1952?1. When steeped in water, they give off abundant, nearly tasteless, mucilage commonly employed as a demulcent. It is sudorific and diuretic, and is given to small children to relieve intestinal troubles. It is a

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remedy for chronic dysentery (Quisumbing, 19511 and influenza (Hooper, 19371. In Malaya and India, Europeans formerly sweetened the mucilage and drank it as a tonic in the hot season (Burkill, 19351. A teaspoonful of the seeds is put in a glass of water with added sugar, and the infusion is drunk to relieve the burning discomfort of urination in cases of gonorrhea and cystitis (Chopra et al., 19581. It is also given to mothers to relieve pain after childbirth (Dastur, 1952?1. The seeds of 0. so~~~~~ L., holy basil, and 0. canum Sims, hoary basil, yield mucilage for the same purposes, though not as plentifully (Oehse and Bakhuizen van Den Brink, 19311. Burkill (19351 said: “If dust enters the eye, a few seeds put against the eyeball will supply mucilage enough to remove it”. Indian chemists report that sweet basil seed mucilage is “unusual in that (al it contains ~-mannuronie and D-galacturonic acids in addition to neutral sugars, and (bl it is associated with appreciable amounts of free and bound lipids and 0-acetyl groups, all of which seem to help the swelling of the mucilage in various solvents. Further, the mucilage was shown to be highly heterogeneous, containing at least three structurally different polysaccharides” (Tharanathan and Anjaneyalu, 19741. LAURACEAE Litsea glutinosa (Lour.1 C.B. Robins (syn. L. chine&s Lam,, L. sebiferu Pers.1. Puso-pus0 This is an evergreen shrub or tree to 25 m tall; its new shoots are downy. The leaves are elliptical to oblong, pointed at the apex, 9-20 cm long. The small, yellowish flowers are massed in clusters in the leaf axils and the round fruit is no more than 8 mm across. A common species throughout India, up to an altitude of 1,250 m, it also occurs in Southeast Asia and the Philippines. The leaves are mucilaginous and are regarded in India as emollient and antispasmodic. In Cambodia, very young leaves are made into a salve for boils (Martin, 1971). The bark gum contains much mucilage, slightly balsamic and mildly astringent. It is commonly sold in India as a demulcent drug, in broken quills or pieces a few centimeters in length, which is taken against diarrhea and dysentery. Ground to a paste, it is applied as an emollient on wounds, bruises, sprains, rheumatic and other swollen joints. It contains laurotetanine, tannin and a red-brown coloring matter (Anon, 1962). LEGUMINOSAE Acuciu Kenneth Willd. Shemba

A high-climbing or spreading, reclining shrub or a small tree, the leaves are bipinnate with small leaflets and spiny rachis. White or light-yellow flow-

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ers in globose beads to 12 mm across are borne in large terminal panicles. The seedpod is thin and flat, to 8 cm long, containing 8-14 seeds. This plant forms impenetrable thickets throughout the arid zone of west tropical Africa, in India and Southeast Asia. In India, the leaf juice is used to relieve gastric distress in infants. Mashed leaves are used to treat oral afflictions and, dried and powdered, are taken to alleviate urinary inflammations, and are also applied to wounds (Watt and Breyer-Brandwijk, 19621. In the Ivory Coast, the leaf juice is administered as an enema to relieve orchitis, whereas the leaf decoction is taken as a febrifuge and to alleviate headache and body pain. A combination of the leaf juice and that of Physalis angulata L. is applied to skin diseases (Burkill, 1935; Irvine, 19611. Watt and Breyer-Brandwijk (19621 commented: “This is probably the plant which is thought to have a powerfully protective mucilaginous juice, one of the most remarkable properties of which is its power of retaining water. It is well known that fire and even hot metal can come in contact with the bare skin without injury, provided the skin is covered with mucilage”. They were quoting from File 38, 1921-26, Amani Research Station, Tanganyika Territory. Trigonella

foenum-graecum L. Fenugreek An erect, strongly aromatic, annual herb, to 60 cm high, the leaves trifoliate with leaflets 2-2.5 cm long. The small, yellowish-white flowers are borne singly or in pairs in the leaf axils. The seedpods are long, narrow, pointed, containing brownish-yellow seeds. It is native to the area from the eastern Mediterranean to Central Asia and Ethiopia, and much cultivated in India and China. When boiled in water, the seeds release a large quantiy of thick mucilage commonly utilized in the past as an emollient in thrush, chapped lips, ophthalmia and gastrointestinal inflammations, and in poulticing boils and abscesses. At present, it is no longer popular because of its peculiar odor and bitter flavor (extracted with alcohol1 (Barton and Castle, 18771, but the seeds are employed in veterinary medicine and cattlefeed (Grieve, 19671. In recent years, fenugreek seed has received much scientific attention as a potential source of steroidal sapogenins (Fazli and Hardman, 1971; Hardman and Fazli, 19721.

LILIACEAE Aloe vera (L.1 Burm. f. (syn.: A. barbadensis Mill.1 Aloe, Barbados aloe (though it is a Mediterranean species), zabila, sabila, savila, or yerba de goma (Spain), sinkle bible (Jamaica), jelly leeks (China). The mucilaginous “gel” of the leaf of Aloe Vera, widely employed as a demulcent, has been the subject of much folk use, internally and externally, and of widespread commercial exploitation; it has even been claimed to be a

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cancer cure. One of its most popular and valid applications is the prevention of sunburn, and healing of sunburn if the skin has not been protected (R. Younger, personal communication). It has been much studied in the hope of discovering a “miracle” ingredient responsible for its healing action (Morton, 19611. Grindlay and Reynolds (19861 have presented a comprehensive review of its uses and the inconclusive results of chemical research. They quoted the present author’s suggestion of 1961 that the seeming efficacy might be attributable to the fact that it is 96% water and provides a means of making water available to injured tissue without sealing it off from the air. In the 1950’s, Dr. Alexander Farkas, a chemist in North Miami Beach, Florida, developed an aloe extract which he called “Epithal”, which could be sprayed on severe burns and other injuries (Morton, 1961); and his color slides showing before-and-after views of patients hospitalized for severe burns and treated with “Epithal” were most impressive. In 1965, he jotted on paper for this author a crude formula of what he believed to be the active principle. On viewing this, the eminent Dr. Jack Beal, Professor Emeritus of Pharmacognosy, Ohio State University, wrote to this author (January 12, 19651: “It appears that his structure is similar to structures of major principles of a number of mucilages. There does appear to be mucilage present in the mesophyll portion of the [aloe] leaf which accounts for the soothing nature. The major principles of these mucilages are often high molecular weight structures made up of uranic acid molecules, thus it is possible that Dr. Farkas has determined the make-up of the mucilage in aloe. However, I do not believe this to be the principle responsible for the stimulation of healing. It should be stated though that I do not have one shred of good scientific evidence to back up my opinion. On the basis of unpublishable data, it is my feeling that the healing stimulant is in the same portion referred to in our recent publication on the bacteriostatic property of aloe” (Lorenzetti et al., 19641. MALVACEAE Abelmoschus

esculentus (L.1 Moench. Okra, gumbo This is a branched, semi-woody, annual or biennial, plant 1 - 3 m high. The leaves are alternate, long-stemmed, widely spaced up the stem and deeply divided, with toothed margins. The stems and leaves are more or less bristly. The flowers are large, pale-yellow with dark-red eye and borne singly in the leaf axils. The ridged pods (capsules), 15-30 cm long and about 2-2.5 cm thick, are normally bristly and irritating to the skin but smooth forms have been developed. There are a number of locules in each pod with a single row of smooth, round seeds in each locule. Okra originated in tropical Africa and has become a commonly cultivated vegetable crop throughout the tropics and subtropics. All parts of the plant are mucilaginous, the pods extremely so, especially when cooked. In the Philippines, a syrup of the pods is taken internally to relieve sorethroat and catarrh, while a deco&ion of the young fruits is given

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as a demulcent to soothe genito-urinary complaints. A soup made of the pods is claimed to be very effective in alleviating dysentery. Emollient poultices are made of the pods and leaves and applied to abscesses and tumors (Quisumbing, 1951; Dastur, 1952?; Chopra et al., 1958; Cruz, 19651. One hundred years ago, an infusion of okra mucilage was employed as a “vehicle for medicines prescribed in diseases of the mucous passages, for enemata, etc.” (Percher, 1868). Okra mucilage is a complex macromolecule consisting of polysaccharide, protein and minerals, with high concentrations of non-carbohydrate components. It is useful in the food manufacturing industry as a substitute for, or extender of, egg white (Woolfe et al., 1977). A purified extract of the ground-up pods (freed of fats and waxes and filtered) was reported in 1951 to be a suitable plasma replacement or blood volume expander (Burrowes, 1951) and this was echoed in India in 1985 (Anon, 19851. However, such a product is unknown to the Scientific Affairs Division of the American Association of Blood Banks and the United States Food and Drug Administration, Division of Blood and Blood Products, declares that it was never certified (personal communication). The mucilage from the green stems is used in India to clarify sugarcane juice in the process of making sugar (Anon, 19851. ORCHIDACEAE Laelia autumnalis L. Flor de todos santos, lirio de San Francisco, diegos. An epiphytic orchid with pseudobulbs to 15 cm long, its cylindrical flowering stem is 30-40 cm high with 3- 6 blooms. The leaves are linear-oblong, up to 17 cm long and leathery. The flowers are sweetly fragrant, typically rose-purple, the trilobate lip white at the base. There are several named cultivars including the all-white “Alba” (Gajon, 1930; Bailey Hortorium, 19761. Native to the states of Morelos, Oaxaca, Tabasco and other warm areas of Mexico, this lovely species is prized in orchid collections everywhere, (Gajon, 1930). A decoction of the flowers is given as a cough remedy in Mexico (Martinez, 19591. The mucilage of the pseudobulbs is used as an adhesive in preparing the animal-shaped confections of sugar and almond oil made for Mexican fiestas (Johnson, 1971). Several other orchid species are employed as emollients. In the case of Oberon&z anceps Lindl., the whole plant is mashed and serves as a poultice. Various species of Dendrobium, especially D. nobile Lindl., are employed as remedies for skin diseases and eruptions (Duggal, 19711. It is also used “to improve appetite, stimulate salivary secretion, and promote general health”. This orchid is unusual in possessing two alkaloids which may be responsible for its reputation as a tonic (Wang and Zhao, 1985). Bletia purpurea DC. Candelaria, pine-pink, or wild ginger This is an erect, terrestrial orchid native to Florida, the Bahamas, the

Greater Antilles, and through Central America to Mexico. Its fresh pseudobulbs contain a spicy, bitter juice. They are split open and applied as an antiseptic on open wounds, cuts and abrasions of the skin. After drying, the pseudobulbs are steeped to make a tea which is given as a stomachic and antidote for fish-poisoning (Leon, 1946; Duggal, 1971). The decoction of the pseudobulbs of Bletiu cutenulata Ruiz et Pav. is used as a remedy for dysentery in Mexico (Martinez, 19591. B. hyacintha R. Br. is much employed in China as an emollient on wounds and burns and the decoe tion is given in cases of fever, pulmonary complaints and dysentery (Petelot, 19541. PEDALIACEAE

A succulent, musk-scented annual herb to 60 cm high, with four-sided, spiny fruits. It is common along the coasts in East Africa, southern India, Sri Lanka and Southeast Asia. When young, fresh leaves and stems are stirred in water, giving it a mucilaginous consistency which lasts lo-12 h. The mucilage has been much used as a demulcent in urinary and bladder in~ammations {Petelot, 19531 and in treating thrush, while the leaves are eaten as treatment for enlarged spleen (Dastur, 1952?). Vendors who adulterate buttermilk with water use the stems to thicken it so that it appears rich. The seeds are mucilaginous and used to make poultices (Lindley and Moore, 1876). Sesamum ~nd~~~rn L. Sesame, or benne This is an erect, annual herb with quadrangular, hairy stems to 90 cm tall. The leaves are simple, close-set, alternate, slender, lanceolate, lobed or toothed, the tubular flowers pink or white, spotted with yellow, red or purple. The fruits (capsules), borne profusely, and erect in the leaf axils, are oblong, short-stalked, ribbed, containing numerous small white, yellowish, brown or black seeds. Believed native to central Asia, sesame is widely cultivated in tropical and subtropical and even subtemperate regions for the edible seeds and for the oil they yield. The leaves are mucilaginous and are poulticed on wounds. The mucilage which exudes when the leaves are boiled or simply steeped in cold water is used as a remedy for chronic diarrhea and other intestinal and urinary disorders (Dastur, 1952?). It is also applied in ophthalmic and skin complaints (Wren, 1970). It is regarded as an all-purpose demulcent (Quisumbing, 1951) and is also used as a shampoo (Burkill, 1935). PLANTAGINACEAE Phtugo major L. Plantain, broad-leaved plantain A perennial or annual stemless plant, the leaves, growing in the form of a

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rosette, are ovate, long-petioled, coarse, sometimes toothed, 15-20 cm long with 5-9 lon~tudinal ribs. Flowers are minute, borne in dense, slender, erect spikes 6- 20 cm long, and are succeeded by small three-loculed capsules with 4-8 black seeds in each locule. The rhizome is short, thick and shrouded by a mass of long, slim, yellowish roots. Native to Europe and northern and central Asia, this common weed has become naturalized throughout the temperate world. The seeds are coated with tasteless and odorless mucilage which is released by maceration in hot water. After boiling to the desired density, the thick liquid was formerly sweetened and given to infants to cure thrush (Grieve, 19671. P. lanceolata L., Narrow-leaved plantain This species is similar to the preceding except that the leaves are longer, no more than 2.5 cm broad, and the flower spike thicker and shorter. The leaves are mucilaginous but contain tannin and are crushed to make astringent poultices, while a decoction is taken to allay oral inflammation (Font Quer, 19731. The seed mucilage has apparently been used only for stiffening fabrics in France (Grieve, 19671. Z? ovuta Forsk. Psyllium, blond psyllium, ispaghula A stemless or short-stemmed, hairy annual herb, its leaves are long and narrow, pointed, recurved, arising in a rosette at ground level. The white flowers are borne in numerous, cylindrical spikes and the ripe capsules open and disperse yellowish-brown seeds, 3 mm long. This plant is native to the Mediterranean region of Europe and North Africa and is cultivated extensively in Iran and India for its seeds. When the seeds are boiled in water, the thin, white seedcoat (called “husk”), greatly expands due to its 25-30%~ mucilage content possessing mainly xylose, arabinose and galacturonic acid (Morton, 1977). It absorbs 25 times its weight of water. The separated “husk’ is much used as a demulcent, mainly as a gentle bulk laxative, and for soothing the intestinal irritation or inflammation which causes diarrhea and dysentery. It absorbs toxins. The whole seeds, on the other hand, actually cause intestinal irritation and even obstruction (Jain, 1968). The mucilage has been taken internally to relieve urinary distress, sorethroat and coughs (Dastur, 1952?f. P. psyllium L., Black psyllium Native to and growing wild in central and southern Europe, and from North Africa to southwestern Asia, black psyllium is cultivated mainly in France and Spain. Its dark-brown or black seeds are not as rich in mucilage as those of the preeeding species, but are employed as demuleents and emollients in the same manner as linseed or flaxseed Linum wit&&mum L., Linaceae, (Grieve, 19671, whose gum, extracted from the pulverized seeds, is omitted here because it is now believed to be unsuitable for medicinal use,

258

due to the difficulty of freeing tler and BeMiller, 19731.

it from potentially

allergenic

proteins

(Whis-

ROSACEAE Cydonia oblonga Mill. Quince

This is a slow-growing, deciduous, large shrub or small tree, to 5-6 m tall. The leaves are alternate, oblong-ovate, pointed, and downy on the underside. The flowers, borne singly at the branch tips, are white tinged with purple. The fruit is obovoid with yellow, velvety skin and astringent flesh, with five locules, each containing 8 to 14 seeds. Perhaps native to Iran and Turkestan, the quince was formerly popular in Greece, Italy, Spain and France and, in the mid-17th Century, became fairly common in England and America, especially in the northwestern United States and also in temperate parts of Latin America. The fruit was mainly used for jelly and marmalade. Cultivation declined but has been recently revived in Brazil and Chile. The seeds are coated with mucilage which is released in boiling water. The decoction, evaporated to dryness and powdered, will form a mucilage in cold water, and this infusion has been much utilized as a demulcent given in cases of gonorrhea, dysentery, diarrhea, thrush, conjunctivitis, pulmonary distress, and as a soothing skin lotion (King, 1855; Manfred, 1947; Grieve, 1967; Wren, 19701. SCHISANDRACEAE Schisandra

chine&s (Turcz.) Baill. Magnolia vine A climbing, twining shrub reaching 8- 10 m in height, its leaves are oblong to obovate, shiny and toothed; the flowers white or pale-rose and sweetly scented. The fruits are small, red, in spikes to 10 cm long. It is native to Manchuria, China and Japan and cultivated as an ornamental in the midwestern United States and against walls in England. A decoction of the mucilage obtained from the branches is drunk to relieve coughs, dysentery and the discomforts of gonorrhea. The fruits as well as the branches contain an abundance of mucilage and that of the fruit is used by Japanese women as a hair-dressing (Stuart, 19111. The report of the American Herbal Pharmacology Delegation to China included medical uses of the dried ripe fruit, and also the statement, “Experimentally, extracts of this plant have shown in vitro activity against Mycobacterium tuberculosis” (Anon, 19751.

SCROPHULARIACEAE Scopariu

dulcis L. Licorice

An erect,

bushy,

weed, sweet broom semi-woody subshrub, 25-80

cm tall, the leaves

are

259

opposite and whorled, narrowly elliptic and finely toothed. The white flowers are borne in pairs in the leaf axils, and are followed by nearly round seed capsules 2 - 3 mm wide. This is a common weed from Georgia and Florida to Louisiana, and in the Bahamas, West Indies and from southern Mexico to Peru. It is also found in many parts of the tropics of the Old World. The leaves when chewed are at first bitter, then sweet. The whole plant, soaked in water, releases much mucilage which is said to purify the water and render it cool and refreshing. After boiling the above-ground parts, the decoction is widely valued as a demulcent and a stomachic “tea”, relieving diarrhea, coughs, bronchitis, and other pulmonary complaints (Friese, 1934; Manfred, 19471. It is also applied to hemorrhoids and various inflammations and contusions (Roig y Mesa, 1945; Cruz, 1965; Pompa, 19741, and, while still hot, on earache and conjunctivitis (Oliver, 19601. In 1920, the decoction was reported in El Salvador and Colombia to be a specific remedy for yellow fever (Guzman, 1947). Japanese researchers have derived five cytotoxic diterpenoids from the whole, dried plant (Hayashi et al., 19881. Verbascum thupsus L. Mullein A biennial plant, mullein has a stout, erect, cylindrical, hairy and semiwoody stem to 2 m tall. The leaves are alternate, oblong, to 30 cm in length, toothed, soft and woolly on both sides, upward-slanting and close-set, their bases clasping the main stem. Downy yellow flowers are densely massed in an erect, terminal cluster. Native to Europe and western Asia, mullein is commonly naturalized throughout the northeastern United States and as far south and west as Mississippi. The mucilaginous nature of the leaves and flowers has caused them to be much used in the past as emollient poultices for all sorts of painful swellings, ulcers, tumors, hemorrhoids and other external ailments (King, 1855; Barton and Castle, 18771. A hot decoction has been effective in cases of dysentery. Milk in which the leaves have been boiled was drunk to overcome chronic coughs (Leyel, 19521. However, the mucilaginous substance is not tasteless and chemically inactive, for it is somewhat bitter and contains a fleeting semi-narcotic element and saponins that are toxic to fish (Millspaugh, 1892; Font Quer, 1973). TILIACEAE Grewia mollis Juss. Kyapotoro (and numerous other tribal names) A common plant of East Africa, this shrub or small tree reaches 6 m in height. Its leaves are lanceolate to oblong, 5- 15 cm long, white-woolly on the underside and coarsely toothed. The fruit is round, 5 mm wide and black when ripe. The flowers and young leaves and very mucilaginous bark are used as ingredients in sauces and soups (Dalziel, 19481. The bark and leaves

260

are applied to wounds, sores and ulcers. The bark mucilage is given as a laxative and a decoction of the bark is employed to bathe wounds. Dried and ground bark serves as a binder for bean meal cakes and the mucilage in solution is useful for coating mud walls and floors of huts (Irvine, 1961). Grewiu optiva Drummond

(syn.: G. oppositifoh Roxb. ex Mast.). Bhimal This tree of medium size (to 13 m high) has a thick trunk. The leaves are ovate, pointed, rough, finely-toothed, and the flowers light-yellow in flat clusters, followed by small, globose, lobed, edible fruits. It is native to southern India, occurring in the wild up to 2,100 m altitude in the Himalayas, and is cultivated on the plains (Anon, 19561. It is valued as a source of timber, fuel, fiber and fodder (Drury, 18731. Joshi (19811 declared that “The bark of the twigs, on being crushed, yields mucilaginous substance which works as an effective detergent to cleanse the human body. In fact, in remote hill areas in [Uttar Pradesh], even today women wash their hair with this detergent substance.” Tilia x europaea

L, European linden (lime in England) A tree of up to 20-40 m tall, the leaves are finely-toothed and heartshaped, the flowers in drooping clusters, sweetly-scented, yellowish or white with the peduncle bearing a thin, oblong, leaflike bract. Native to Europe, it is commonly cultivated in the milder parts of the British Isles and occasionally in the upper midwest of the United States and in Argentina. In all parts of the tree, particularly the inner bark, there is a soft mucilage, long used as a treatment for burns, scalds and inflamed swellings. The sap which flows from cuts made in the trunk and branches is rich in mucilage and has been boiled and clarified to make a kind of sugar. If allowed to ferment, the sap becomes wine (Barton and Castle, 18771. The flowers and floral bracts from this tree and its close relatives contain a colorless, fragrant, volatile oil. An infusion was formerly prescribed to relieve nervousness and indigestion, headache and hysteria. A hot infusion was taken to halt diarrhea, and a hot bath enriched with the flowers and bracts served as a soporific (Wren, 19701. The dried flowers and bracts are packaged and exported from Europe to the Caribbean Islands and Latin America and to the United States and sold in “boticas” and “health food stores”, respectively, for making “tea” (Morton, 1975). Triumfetta

luppulu L. Burweed, mozote de caballo A shrub to 2 m high, it has long-petioled, softly hairy, ovate, pointed, more or less three-lobed and toothed leaves. The small, inconspicuous, yellow flowers are arranged in hairy, spike-like panicles. The nearly globose, hairy seed capsules (bursl, 6-8 mm wide including the barbed spines, contain small, pear-shaped seeds.

261

The plant is native and wild at low elevations from southern Mexico through Central America to northern South America. It is also found in the West Indies and western Africa. The leaves, flowers, bark and stems, and also the roots, are rich in mucilage which is readily released by crushing the parts in hot water and steeping for 1 h. Bundles of twigs for crushing and soaking in cold water for several hours are sold in Costa Rican herb markets (Anon, 1976). The mucilage, which is slightly astringent, is widely used in Latin America to dispel chronic diarrhea (Aguilar Giron, 19661, to treat gonorrhea, leucorrhea and hemorroids (Roig y Mesa, 19451, and relieve colds (Standley, 19231. For the latter purpose, the infusion is warmed and flavored with lemon juice and sugar. To overcome an alcoholic “hangover”, the drink is taken cold, and is often served in Costa Rican bars. Pounded twigs are put into horses’ drinking water as a tonic (Anon, 19761. The mucilage is also applied on “itching wounds” (Altschul, 19731. Burweed mucilage is used to clarify the syrup in sugar-making and to coat the moulds to prevent loaves of sugar from adhering to them (Anon, 19761. L., Burbush A shrub very similar to the preceding, it has even more variable leaves, ranging from ovate or heart-shaped to oblong, and irregularly lobed and toothed. In distribution, it ranges not only from Mexico to Chile and through the West Indies, but also to the Bahamas, Bermuda and southern Florida and has become naturalized as a weed in Hawaii. Its mucilage is employed for the same purposes as that of T. lappuh; sometimes the crushed leaves are infused in wine (Standley, 1923; Roig y Mesa, 1945; Lavadores Villanueva, 1969; Pompa, 19741. T. semitriloba

ULMACEAE Ulmus rubra Muhlenb. (syn.: U. fulva Michx.1 Slippery elm

A deciduous, rough-barked tree to 25 m tall with trunk to 75 cm thick. The leaves are alternate, ovate, sharp-pointed, irregularly toothed, hairy and rough on both sides. Native from Quebec to North Dakota and south to Virginia, northwest Florida and eastern Texas, it is most often seen in the western part of its range (Vestal and Schultes, 1939); it is occasionally cultivated in the United States and to a limited extent in the British Isles (Chittenden, 19511. The inner bark is very mucilaginous and fragrant. In former times, in the United States and in England, it was highly valued as an emollient, especially to relieve inflammation of the urinary tract and to treat diarrhea and dysentery. It was given to aid digestion, often applied to skin eruptions and used as a vehicle for medications (Percher, 18681. The inner bark was pressed flat and dried and exported in strips about 5 cm wide. Wren (1970)

262

declared it “one of the most valuable articles in the botanic practice”. North American Indians took a deco&ion of the bark as a laxative and to aid delivery in childbirth (Vestal and Schultes, 19391. North American Indians and country folks chewed the fresh bark as a masticatory. Slippery elm lozenges were popular for soothing hoarseness and sore-throat, and are still sometimes sold in New England. The powdered bark was mixed with milk to make a gruel for patients suffering from bronchitis or stomach inflammation. A plain infusion was injected to overcome bowel inflammation in infants (Wren, 19701, while the powder was employed for sprinkling on or poulticing all surface inflammations - burns, wounds, ulcers, boils, skin diseases, even ophthalmia (King, 1855; Wren, 19701. VITACEAE C&us trifoliata L. Sorrel vine This semi-woody vine climbs to 5 m. The leaves are in threes, each composed of three coarsely toothed, fleshy leaflets to 9 cm long. The fruits are dark-purple in flat clusters. Common in the wild from Baja California through Central America and northern South America, it is also found in the West Indies, the Bahamas, southern Florida and the Florida Keys. The mucilaginous young stems and leaves are crushed and applied as a poultice on boils, mange, ringworm and other skin diseases, headache, swollen knees and inflammations. The leaf infusion is taken to relieve bronchial af~ictions (Standley, 1930; Martinez, 1959; Lavadores Villanueva, 19691. The tubers are emetic and purgative (Martinez, 19593. The fresh leaves are acid in flavor and have been consumed as a food flavoring in Jamaica (Standley, 19231. Conclusions

It is clear that some plant mucilages have been studied and found to be linked with certain biologically active properties, but it is also clear that mucilage per se has a benevolent affinity for human (and other animal) tissue, else why would it have been so universally, consistently and successfully employed in healing? The usage of water-holding mucilage, however primitive or antiquated or modern, deserves public and scientific attention. After all, we know that firewalkers can trot unharmed over red-hot coals simply because they first wet their feet! A colleague informed this author that he gained fame at college parties by secretly coating his thumb and forefinger with aloe gel, then plucking hot coals, one by one, from a fire to light companions’ cigarettes (Smith, M., personal communication). Another related that he has seen workers in an aluminum foundry wet their hands and then pass them through molten aluminum without harm (Grabowski, C., personal communication).

263

The use of mucilage as fire protection is apparently known in Australia, for this author has been told of an announcement on United States cable television (Cable Education Network, Discovery Channel, Beyond 2000, Episode 15; December 9, 1989) that Australians have developed a mucilage-saturated blanket to enable people to run safely through a forest or grass fire. For treating burns, chopped leaves of Melaleuca quinquenervia S.T. Blake are added to the mucilage for their antiseptic oil (Kelley, R., personal communication). However, a blanket treated with mucilage plus MeZaZeuca leaves could be a hazard if exposed to flame. The volatile eucalyptol in Melaleuca leaves is highly flammable, causing “torching” and wildfire when Melaleuca quinquenemia trees are burning in southern Florida wilderness (Wade et al., 1980). The related Eucalyptus trees also fuel wildfires in Australia. It would seem more feasible to store powdered mucilage to be rehydrolyzed for spraying (as was done with Dr. Farkas’ “Epithal” (aloe)) in high-risk areas such as airports, instead of storing blankets. If firemen, as well as passengers fleeing a burning aircraft, could be effectively sprayed with protective mucilage, it would be negligent not to make it readily available in usable form. Perhaps municipal fire engines could likewise be supplied with sprayable mucilage. The prospect should merit research and experimentation. From the standpoint of healing, it seems reasonable to conclude that many more people than are currently aware of mucilage, could undoubtedly be benefitted by it in many ways, at little cost. References Aguilar Giron, J.I. (1966) Relation de Unos Aspectos de la Flora l?titil de Guatemala Tipografia National de Guatemala, for “Amigos de1 Bosque”, Guatemala, Central America, p. 362. Altschul. S.v.R. (1973) Drugs and Foods from Little-known Plants. Harvard University Press, Cambridge, M, p. 186. Andy, E.O.N. and Eka, O.U. (19851 Nutritive value of leaves of baobab tree (Adansonia digitata). West African Journal of Biology and Applied Chemistry 30,310. Anonymous (19561 Wealth of India: Raw Mate+&. Vol. IV. Council of Scientific and Industrial Research, New Delhi, p. 261. Anonymous (19621 Wealth of India Raw Materials. Vol. VI. Council of Scientific and Industrial Research, New Delhi. Anonymous (19661 Wealth of India Raw Materials. Vol. VII. Publication and Information Directorate, Council of Scientific and Industrial Research, New Delhi. Anonymous (19691 Wealth of Zndia: Raw Materials. Vol. VIII. Publication and Information Directorate, Council of Scientific and Industrial Research, New Delhi, pp. 153- 154. Anonymous (19751 Herbal Pharmacology in the People’s Republic of China National Academy of Science, Washington, D.C., p. 215. Anonymous 09761 What is it? A guide to typical Costa Rican Foods - Mozote de Caballo. Tico Times, San Jose, C.R. January 28. Anonymous (19851 Wealth of India: Raw Materials. Vol. 1 (Revised Edition). Publication and Information Directorate, Council of Scientific and Industrial Research, New Delhi, p. 8. Bailey Hortorium (1976) Hortus III, a Concise Dictionary of Plants Cultivated in the United States and Canada Macmillan, New York, p. 631.

264

Barton, B.H. and Castle, T. (1877) The British Flora Medica A History of the Medicinal Plants of Great Britain (New Edn.) Chatto and Windus, Picadilly, London. Boakye-Yiadom, K. (1977) Antimicrobial properties of some West African Medicinal Plants. Quarterly Journal of Crude Drug Research 15,201202. Burkill. I.H. (1935) Dictionary of the Economic Products of the Malay Peninsula. Crown Agents for the Colonies, London. Burrowes, H. (1951) Cheap blood plasma substitute made from okra plant. Miami Herald, January 28, p. 8B. Chittenden, F.J. (Ed.) (1951) The Royal Horticultural Society Dictionary of Gardening. Vol. IV. Oxford at the Clarendon Press. p. 2177. Chopra, R.N., Chopra, I.C., Handa, K.L. and Kapur, L.D. (1958) Chopra’s Indigenous Drugs of India 2nd Edn. U.N. Dhur & Sons Pvt. Ltd., Calcutta. Cruz, G.L. (1965) Livro Verde das Plantas Medicinais e Zndustrias do Brasil Vols. I & II. Velloso S.A., Belo Horizonte, Brazil. Dalziel, J.M. (1948) Useful Plants of West Tropical Africa (Appendix to The Flora of West Tropical Africa). Crown Agents for the Colonies, London. Dastur. J.F. (19527) Medicinal Plants of Indiaand Pakistan. D.B. Taraporevala Sons & Co., Ltd., Bombay. Datta, S.C. and Datta, D.D. (1961) Pharmacognostical study of the seeds of Lepidium sativum Linn. Journal of Science and Industrial Research 200, 60 - 62. Drury, N. (1873) The Useful Plants of India. Wm. H. Allen & Co., London, p. 235. Duggal, S.C. (1971) Orchids in human affairs. Quarterly Journal of Crude Drug Research 11, 1727 - 1734. Fazli, F.R.Y. and Hardman, R. (1971) Isolation and characterization of steroids and other constituents from Trigonella foenum-graecum. Phytochemistry 10, 2497-2503. Font Quer, P. (1973) Plantas Medicinales - El Dioscorides Renovado. 2nd Edn. Editorial Labor, S.A., Barcelona, Spain. Friese, F.W. (1934) Pluntas Medicinaes Brasileiras. Instituto Agronomic0 do Estado Sao Paulo, Brazil, p. 474. Gaind, K.N. and Gupta, R.L. (1971) Flavonoid glycosides from Kalanchoe pinnata. Planta Medica 20, 369-373. G6jon Sanchez, C. (1930) Las Mejores Orquideas de Mexico. Talleres Tipograficos “La Pluma Fuente”, Mexico, D.F., p. 53. Grieve, M. (1967) A Modern Herbal. Vols. I & II. Hafner Publishing Company, New York. Grindlay, D. and Reynolds, T. (1986) The Aloe vera phenomenon: A review of the properties and modern uses of the leaf parenchyma gel. Journal of Ethnopharmacology 16, 117-151. Guzman, D.J. (1947) Especies de la Flora Salvadorelia Imprenta National, San Salvador. El Salvador. Hardman, R. and Fazli, F.R.Y. (1972) Studies in the steroidal sapogenin yield from Trigonellu foenum-graecum seed. Planta Medica 21, 322-328. Hooper, D. and Field, H. (1937). Useful Plants and Drugs of Iran and Iraq. Field Museum of Natural History, Chicago, IL, p. 145. Hayashi, T., Kishi, M., Kawasaki, M., Arisawa, M. and Morita, N. (1988). The crystal structure of scopadulcic acid A from Paraguayan crude drug “Typycha Kuratu” (Scopariu dulcis). Journal of Natural Products 51, 360-363. Irvine, F.R. (1961) Woody Plants of Ghana, with Special Reference to Their Uses. Oxford University Press, London. Jain, S.K. (1968) Medicinal Plants. National Book Trust, New Delhi, pp. 112- 113. Johnson, F.B. (1971) Dulces de 10s pseudobuibos de orquideas. Orquidea 1, 29-34. Joshi, D.C. (1931) Bhimal - a tree for fodder, fuel and fibre. Indian Farming 31, 17. King, J. (1855) American Eclectic Dispensatory. Moore, Wilstach. Keys & Co., Cincinnati, Ohio. Lavadores Villanueva, G. (1969) Estudio de lus 119 Plantas Medicinas Conocidas en Yucatan, Mexico. Universidad National Autonoma de Mexico, Mexico, D.F. Leon, H. (Sauget y Barbier, J.S.) (1946) Flora de Cuba Contribuciones Ocasionales de1 Museo de Historia Natural de1 Colegio de la Salle No. 8. Cultural, S.A., Havana, p. 390.

265 Leyel, C.F. (19521 Green Medicine.

Faber & Faber, Ltd., London, pp. 112-113.

Lindley, J. and Moore, T. (18761 The Treasury of Botany: a Popular Dictionary of the Vegetable Kingdom. Longmans, Green & Co., London, p. 855. Long, R.H. and Lakela, 0. (1971) A Flora of Tropical Florida University of Miami Press, Coral Gables, Florida, p. 627. Lorenzetti, L.J., Salisbury, Beal, J.L. and Baldwin, J.N. (19641 Bacteriostatic property of Aloe vem. Journal of Pharmaceutical Science 53, 1287. Manfred, L. (1947) 7000 Recetas Botanicas, a Base de HO0 Plantas Medicinales Americanas. Editorial Kier, Buenos Aires, Argentina. Martin, M.A. (19711 Introduction a 1’Ethnobotanique du Cambodge. Centre National de la Recberche Scientifique, Paris, p. 150. Martinez, M. (1939) Las Plantas Medicinules de Mexico. Ediciones Botas, Mexico, D.F. Millspaugh, C.F. (18921 American Medicinal Plants. 1974 reprint. Dover Publications, New York, pp. 432-434. Morton, J.F. (1961) Folk uses and commercial exploitation of aloe leaf pulp. Economic Botany 15, 311-319. Morton, J.F. (19671 The Cadushi (Cereus repandus Mill.), useful cactus of Curacao. Economic Botany 21.185-191. Morton, J.F. (19751 Is there a safer tea? Morton Arboretum Bulletin 26, 24-30. Morton, J.F. (1977) Major Medicinal Plants: Botany, Culture and Uses. Charles C. Thomas, Springfield, IL, pp. 325-327. Nunez Melendez, E. (19751 Plantas Medicinales de Puerto Rico. Estacion Experimental Agricola, Rio Piedras, Puerto Rico. Ochse, J.J. and Bakhuizen van Den Brink, R.C. (19311 Vegetables of the Dutch East Indies (English Edn. of Zndkche Groentenl. Department of Agriculture, Industry and Commerce, Java, pp. 356 - 357. Oliver, B. (19601 Medicinal Plants in Niger&z Nigerian College of Arts, Science and Technology, Ibadan. Parsa. A. (19601 Medicinal plants and drugs of plant origin in Iran. IV. Qualitas Pluntarum et Mate&e Vegetabiles 7, 5- 136. Petelot, A. (19531 Plantes Medicinales du Cambodge, du Laos et du Vietnam. Vol. II, No. 18. Centre National de Recherches Scientifiques et Techniques, Saigon, p. 229. Petelot, A. (1954) Plantes Medicinaks du Cambodge, du Laos et du Vietnam. Vol. III, No. 22. Centre National de Recherches Scientifiques et Techniques, Saigon, pp. 190- 191. Pompa, G. (19741 Medicamentos Indigenas. 41st Edn. Editorial America, S.A., Miami, Florida. Porcher, F.P. (18681 Resources of our Southern Fields and Forests, Medical, Economical and Agricultural Being Also a Medical Botany of the Confederate States. Steam-Power Press of Evans & Cogswell, Charleston, S.C. Quisumbing, E. (19511 Medicinal Plants of the Philippines. Technical Bulletin No. 16. Philippine Department of Agriculture and Natural Resources, Manila. Roig y Mesa, J.T. (19451 Plantas Medicinales, Aromaticas o Venenosas de Cuba Cultural, S.A., Havana, Cuba. Safford, W.E. (19051 Useful Plants of the Island of Guam. Contribution of the United States National Herbarium, Vol. IX., Washington, D.C. Small, J.K. (19331 Manual of the Southeastern Flora Published by the Author. New York Botanical Garden, Bronx Park, New York. (Reprinted 1953, University of North Carolina Press, Chapel Hill, N.C. p. 265. Standley, P.C. (19231 Trees and Shrubs of Mexico. Contribution of the United States National Museum, Vol. 23, Part 3. Smithsonian Institution, United States National Herbarium, Washington, D.C. Standley, P.C. (19241 Trees and Shrubs of Mexico. Contribution of the United States National Herbarium, Vol. 23, Part 4. Smithsonian Institution, United States National Herbarium, Washington, D.C. Standley, P.C. (19301 Flora of Yucatan. Pub. 279. Botany Series Vol. III, No. 3. Field Museum of Natural History, Chicago, IL, p, 343.

266 Standley, P.C. and Williams, L.O. (1962) Flora of Guutemalu Fieldiana: Botany Vol. 24, Part 7 (No. 21, Chicago Natural History Museum, Chicago, IL. pp. 227 - 228. Standley, P.C. and Williams, L.O. (19733 Flora of sternal Fieldiana: Botany Vol. 24, Part 9 (Nos. 3 & 4). Field Museum of Natural History, Chicago, IL, p. 257. Stuart, G.A. (1911) Chinese Mate& Me&a - Vegetable Kingdom. American Presbyterian Mission Press, Shanghai, p. 398. Swinyard, E.A. and Pathak, M.A. (1980) Surface-acting drugs. Chapter 40, pp. 951-952. In: L.S. Goodman and A. Gilman (Eds.), The Pharmacological Bards of Therapeutics. 6th Edn. Macmillan Publishing Company, inc. Th~anathan, R.N. and Anjaneyalu, Y.V. 0974) Polysaeeharides from the seed mucilage of Ocimum basilicurn Linn. In&m Journal of Chemistry 12,1164-1165. Tyler, V.E., Brady, L.R. and Robbers, J.E. (1981) Pharmacognosy. 8th Edn. Lee & Febiger, Washington Square, Philadelphia, PA. Vestal, P.A. and Sehultes, R.E. (1939) The Economic Botany of the Kiowa Indians a8 it Relates to the History of The Tribe. Botanical Museum of Harvard University, Cambridge, MA, pp. 23-24. Wade, D., Ewel, J. and Hofstetter, R. (1980). Fire in South Florida ecosystems. United States Department of Agriculture Forest Service Technical Report SE-l?. Southeastern Forest Experiment Station, Asheville, N.C. pp. lOO- 103. Walker, A.R. and Sillans, R. (1961) Les pluntes &i&s de Gabon. Encyclopedic Biologique LVI. Editions Paul LeChevalier, Paris. Wang, H. and Zhao, T. (1985) Dendrobine and 3-hydroxy-2-oxodendrobine from Dendrobiplm ROZ” &. Journal of ~atuTa1 Products 48, 796-801. Watt, J.M. and Breyer-Brandwijk, M.G. 0962) Medicos and Poisonous Plants of Southe~ and Eastern Africa. E. & S. Livingstone, Ltd., Edinburgh and London. Whistler, R.L. and BeMiller, J.N. (Eds.) (1973) Industrial Gums Polysaccharides and Their De&atives. 2nd Edn. Academic Press, New York. Williams, R.O. and Williams, R.O., Jr. (1951) Useful and Ornamental Plants of Trinidad and Tobago. 4th Edn. Guardian Commercial Printery, Port-of-Spain, Trinidad, p. 97. Woolfe, MJ., Chaplin, M.F. and Otehere, G. (19771.Studies on the mucilages extracted from okra fruits Wbiscus esculentus L.), and baobab leaves ~~nson~ digitata L.1. Jo~~aZ of the Science of Food and Agriculture 28,519 - 529. Wren, R.W. (1970) Potter’s New Cyclopedia of Botanical Drugs and Preparations. 7th Edn. Health Science Press, Sussex, England. Yamagishi, T., Haruna, M., Yen, X.-Z., Chang, J.-J. and Lee, K.-H. (1989) Antitumor agents, 110. Bryophyllin B, a novel potent cytotoxie bufadienolide from Bryophylkm pinnatum. JournQl of Natural Products 52,1071- 1079.