Binds fluoride. Very useful in areas where fluorosis is a public-health
Indo name: Assem
[a] For correspondence: National Institute of Nutrition, Indian Council of Medical Research, Jamai Osmania PO, Hyderabad 500 007, Andhra Pradesh, India. Fax: 91-40-7019074. Email: email@example.com
SUMMARY: The effect of tamarind ingestion on fluoride retention was studied in three groups of dogs – control (Group I), fluoride-supplemented (Group II), and fluoride and tamarind-supplemented diets (Group III). The urinary excretion of fluoride was significantly higher in Group II (2.45 ± 0.39 mg F/day) and Group III (3.78 ± 0.35 mg F/day) as compared to Group I (0.205 ± 0.21 mgF/day). The difference between Group II and III was also significant. The femur fluoride content of Group II animals (4.0 ± 0.67mg F/gm ash) was significantly higher as compared to that of Group III (2.0 ± 0.52 mg F/gm ash) suggesting a beneficial effect of tamarind ingestion on fluoride retention and toxicity. There were no significant differences in hematological parameters between the groups, although hemoglobin levels and packed cell volume tended to be lower in Group III as compared to Group I. Histopathological study showed that except in kidneys where congestion and tubular changes were greater in experimental groups as compared to control, all other organs were comparable between the groups.
Keywords: Bone fluoride, Femur fluoride, Fluoride toxicity, Tamarind ingestion, Urinary fluoride.
Fluorosis is an important public health problem all over the world. However, drugs are not available for the treatment of skeletal fluorosis, making medical intervention impossible. It is reported that serpentine is of therapeutic value but opinion is divided about its efficacy and toxicological evaluation is not avail-able. 1 Calcium supplementation interferes with fluoride absorption in animals 2,3 and humans, presumably due to the strong affinity between Ca ++ and fluoride and the low solubility of CaF2. Calcium chloride and calcium gluconate have been used in acute fluoride poisoning.4 Intravenous administration of magnesium compounds (MgO or Mg(OH)2) is been reported to increase excretion of fluoride in urine and faeces 5,6 and decrease the amount retained in bones. Aluminium sulphate and boron have also been tried for this purpose.7,8
Sriramachari 9 and Maruthamuthu et al 10 reported the binding of fluoride by tamarind in vitro. However, the effect of tamarind ingestion on fluoride metabolism has not been studied. The present study in dogs was initiated to assess the effect of tamarind ingestion on the urinary excretion of fluoride, the mineral composition (F, Ca, Mg, and P content) of bones, and histopathological and he-matological parameters.
MATERIALS AND METHODS
A total of 18 mongrels, 2.5 to 3.0 months old and weighing 3.5 to 4 kg were used for the study. The animals were acclimatized to laboratory conditions for three months and then were randomly distributed into three groups: Group I (Control) was on a stock diet of cooked rice and pulses; Group II was fed a stock diet + sodium fluoride (10 mg/dog/day); and, Group III was fed a stock diet + sodium fluoride (10 mg/dog/day) + tamarind paste.
The dogs were housed individually with free access to diet and water for a further period of 3 months. Fluoride was administered to the dogs in pieces of bread. Fluoride solution (10 mL containing 10 mg NaF) was layered on a piece of bread and administered without wastage. Bread without fluoride was also fed to control dogs. Ten grams of Tamarind paste, a ready-to-eat commercial product made of whole ripened tamarind pulp after removal of pericarp and seeds and containing 60% moisture, were mixed with cooked rice + red gram (2:1) and served to Group III dogs.
During the last week of the experiment, animals were transferred into metabolic cages. Then, 24-hour urine samples (with few drops of toluene) and faeces were collected for four days. Blood samples were collected (with EDTA as anti-coagulant) and hemoglobin, PCV, total leukocyte count estimations, and peripheral smear determinations, were made. All animals were then given thiopental (Pentothal 50 mg/kg body weight) by i/v. Death was instantaneous. Their lungs, liver, kidney, pancreas, and intestine were removed, fixed in 10% neutral buffered formalin and subjected to routine histopathological examination. Out of the original total of 18 dogs, two in Group I and one each in Groups II and III died early in the initial stages of the study and hence were not included in the results. Also, one animal each of Group II and III died one and two days, respectively, before the conclusion of the experiment for unknown reasons. In these two animals, blood and urine samples could not be collected, but the bones and other organs were included for analysis.
Fluoride content of urine and bone ash 11 was determined with a fluoride ion-selective electrode (Orion Expandable Ion Analyzer EA 940, Boston, MA). Calcium and magnesium in bone ash were determined by atomic absorption spectro-photometry. Phosphorus was estimated by the method of Chen et al.13
Food intake and weight gains were similar in all groups. The average water consumption was significantly less in experimental groups than in controls (312 mL, 63 mL, and 70 mL in Groups I, II, and III, respectively). The volume of urine excreted by experimental Groups II and III was also significantly less (P <0.05) than that of controls (Table 1). There was no significant difference in urine pH among the groups (Table 1).
Biochemical study: Dogs fed the diet containing tamarind (Group III) had significantly higher urinary fluoride excretion (P <0.01) than Group II (Table 1). These results show that the retention of fluoride in Group III was less than in Group II. Also, estimation of fluoride in femur bone indicated that accumulation of fluoride in that bone was significantly less (P <0.01) in Group III than in Group II (Table 2). There was no significant difference in femur calcium, magnesium, and phosphorus content between groups (Table 2).
Hematological study: The hematological parameters of the various groups were not significantly different, although a trend could be seen in Group III suggesting lower Hb% and PCV values as compared to Group I (Table 3). The mean neutrophil and lymphocyte counts were different between Group I and Group II. However they were not statistically significant.
Histopatholgical study: The lungs, liver, kidney, pancreas, and intestines of all animals were examined in order to look for any adverse effects on Group II and Group III as compared to Group I. No gross abnormalities were detected in the organs examined.
Microscopically, the pancreas and intestines showed no changes in all the groups while lungs showed grades I and II pneumonic changes in all groups. Foreign body giant cell reaction, edema, and other changes in lungs were greater in the experimental groups. Liver changes were almost comparable in all groups. More glomerular and tubular changes were seen in the experimental groups (Table 4) as compared to controls.
It is known that high protein intake increases fluoride excretion and decreases fluoride retention in bones of rats,14 and similar results were observed in the present study. Chinoy and Mehta 15 described the beneficial effects of glycine and glutamine on testis of fluoride treated mice. Though bones were not studied, the authors suggest that a protein-supplemented diet may ameliorate the toxic effects of fluoride in endemic areas. Some reports 14,16 indicate that increased gastric acidity enhances fluoride absorption due to formation of non-ionic hydrogen fluoride. It remains to be seen whether tamarind exerts such an effect. It is known that an acidic urine increases fluoride excretion, but in the present study, the urine samples of all the groups did not show any significant differences in pH. Tamarind and fluoride had no adverse effects on hematological parameters studied, although in another investigation fluoride was shown to reduce hemoglobin and hematocrit levels in rabbits.17 Lungs, liver, and kidney did not show any gross abnormalities. However, the exact mechanism by which tamarind ingestion decreases fluoride retention in bones is not known. Increased urinary excretion is one contributing factor. Tamarind contains considerable amounts of tartaric acid. Tartrate-resistant acid phosphatases are known to be present in bone cells,18 but the effect of tartrate-sensitive phosphatases, if any, in bone is worth looking into. Although the therapeutic value of tamarind in the management of urolithiasis has received attention in recent years,19 its potential usefulness for fluorotic patients as suggested by the present study requires further investigation, which is now in progress.
We thank the Director of the National Institute of Nutrition for her interest in the study and Dr. S. Sriramachary for helpful discussions. We also thank Dr. P. Suresh, of NCLAS for animal care.
for fluoride intoxication [editorial]. Fluoride 1980;13:96-9.
2 Wagner JJ, Muhler JC. The effect of calcium and phosphorus on fluoride ab-sorption. J Dent Res 1960;39:49-52.
3 Jowsey J, Riggs BL. Effect of concurrent calcium ingestion on intestinal ab-sorption of fluoride. Metabolism 1978;27:971-9.
4 Yolken R, Konecny PH, McCarthy P. Acute fluoride poisoning. Pediatrics 1976;58:90-5.
5 Rao SR, Murty KJR, Murty TVSD, Reddy SS. Treatment of fluorosis in humans. Fluoride 1975; 8:12-24.
6 Raja Reddy D, Lahiri K, Ram Mohan Rao NV, Vedanayakam HS, Ebenezer LN, Suguna Ram Mohan. Trial of magnesium compounds in the prevention of skeletal fluorosis - An experimental study. Fluoride 1985;18:135-40.
7 Franke J, Runge H, Bech R, Wiedner W, Kramer W, Kochmann A, et al. Boron as an antidote to fluorosis? Part I: Studies on the skeletal system. Fluoride 1985;18:187-97.
8 Gründer HD, Fluorimmissionswirkung auf Rinder. Zbl Vet Med A 1972;19: 229-302.
9 Sriramachari S. Crystalloid interaction with particular reference to fluoride ion and its possible implications of Fluorosis. Arogya 1983;6:17-23.
10 Maruthamuthu M, Venkatanarayana Reddy J. Binding of fluoride with tamarind gel. Fluoride 1987;20:109-12.
11 Tusl J. Direct determination of fluoride in human urine using fluoride electrode. J Clin Chem Acta 1970;27:216-8.
12 Singer L, Armstrong WD. Determination of fluoride in bone with the fluoride electrode. Anal Chem 1968;40:613-4.
13 Chen Jr. PS, Toribara TY, Warner H. Microdetermination of Phosphorus. Anal Chem 1956;28:1756-8.
14 Carold DB, Floriant LC. Influence of type and level of dietary protein on fluoride bioavailability in rat. J Nutr 1987;117:2086-90.
15 Chinoy NJ, Mehta D. Beneficial effects of the amino acids glycine and glutamine on testis of mice treated with sodium fluoride. Fluoride 1999;3:162-70.
16 Whitford GM, Pashley DH. Fluoride absorption the influence of gastric acidity. Calcif Tissue Intl 1984;36:302-7.
17 Hirao Mitsugi. Blood picture of experimental fluorosis. Part I: Changes of erythrocyte, hemoglobin, color index, reticulocyte, blood platelets and the size of erythrocyte, Fluoride 1975;5:33-5.
18 Baron R, Webb L, Tran Van P, Nefussi JR, Vignery A. Kinetic and cytochemical identification of osteoclast precursors and their differentiation into multinucleated osteoclasts. Am J Pathol 1986;122:363-78.
19 Rather P, Pennies AK, Had S, Sharma K, Singh PP. Effectiveness of tamarind (Tamarinds indicus) therapy (3GMx10GM) on calcium oxalate and calcium phosphate crystallization using three different methods. Indian J Clin Biochem 1993;8:136-43.
by the International Society for Fluoride Research - Editorial Office:
17 Pioneer Crescent, Dunedin 9001, New Zealand
Tamarind;Francese: Tamarinier, Tamarin.
Tedesco: Tamarinde, Tamarindebaum;Spagnolo: Tamarindo.
Famiglia. Leguminose (Papilionacee).
Habitat e descrizione. E' maestoso, è un albero che può essere alto dai dieci ai venticinque metri; è originario dell'Africa equatoriale (Madagascar) e cresce nelle regioni tropicali e subtropicali. E' un sempreverde dal caratteristico fusto ramificato fin dalla base, porta foglie alterne e fiori giallo-arancio.
Note storiche.Gli Arabi lo chiamarono Tamara hindi, da tamar che significa dattero e hindi che vuol dire indiano. Conosciuto nel IX secolo dal medico persiano Alhervi e dalla Scuola medica salernitana, le virtù mediche del tamarindo erano già conosciute, nel 1500, dal Mattioli che lo indicava atto a <<muovere il corpo>>. Il medico Abd-al-Latif (1150-1220), che esercitava a Bagdad, per il mal di denti consigliava un infuso di tamarindo e canfora. Il dottor Antonio Campana, invece, nel 1821, consigliava: <<Hanno i tamarindi virtù purgativa, controstimolante, rinfrescante, e si usano nelle febbri gastriche infiammatorie, nell'itterizia, nella dissenteria. Si dà in sostanza, in decotto, o si scioglie in acqua pura, o in qualche infusione. Dose da un'oncia a due. Per decotto due once in una libbra di acqua>>. Nella Storia naturale medica si descrivevano alcuni metodi di preparazione: <<Questi albero dà frutti adoperati in medicina. Alle Antille si tagliano nella metà dell'anno, nel momento in cui il lor epicarpo divien fragile. Si rompe questo e lo si leva press'a poco interamente, poi si incassano ricoprendolo di sciroppo bollente. Dopo il raffreddamento del liquido si chiudono le casse>>.
Parti usate. Polpa del frutto.
Componenti principali. Zuccheri, aminoacidi, acido tartarico, malico, citrico, succinico. La polpa del frutto contiene una quantità variabile di grassi, proteine, pectine, vitamine, minerali (soprattutto calcio, fosforo, potassio), aromi volatili, beta-sitosterolo; un principio amaro che sembrerebbe avere un'azione funghicida sulle culture di Aspergillus niger e di Candida albicans, e attività antibatterica (su Stafilococco aureo, Escherichia coli, Pseudomonas aeruginosa).
terapeutiche. La polpa del frutto, opportunamente purificata mediante dissoluzione
in acqua bollente, viene quindi setacciata e il liquido ottenuto si concentra
a bagnomaria; può essere così utilizzata per l'uso medico
e la preparazione di bevande. A basse dosi regolarizza la funzione intestinale,
mentre a concentrazioni più alte ha effetto lassativo, senza provocare
dolori colitici. Il tamarindo è utilizzato (la polpa) in Sudan come
purgativo, antimalarico, antimicrobico, per il trattamento della dissenteria
e delle febbri reumatiche, ma anche nella preparazione di bevande rinfrescanti.
Alcuni studi scientifici effettuati dall'Università di Khartoum,
in Sudan, hanno evidenziato che la polpa del frutto di tamarindo è
altamente tossica per tutti gli stadi del ciclo di vita di un parassita
del sangue: lo schistosoma mansoni.
Si legge sul Mattioli (1557, p.135 ) " Il significato del uocabolo Arabico fa, che si tengano essere una spetie di Dattoli d'India anchora i TAMARINDI. imperoche Tamar, Arabica dittione nella nostra lingua: ne altro uuol rileuare Tamarindi, che Dattoli Indiani. Producono questi (secondo che recita Serapione) alcuni alberi, li quali fanno le fronde loro lunghe, et appuntate, simili molto à quelle del salice; come alcuni uogliano, che sieno i frutti delle Palme saluatiche. A' noi se ne portano pochi d'intieri: ma il più delle uolte tutti pesti, et messi insieme, come una pasta, nella quale si ritrouano i suoi noccioli gialli di diuerse forme". Ancora secondo il Mattioli i Tamarindi "Muouono il corpo: et imperò deuuti, soluono facilmente la cholera, et gli humori adusti. Conferiscono alla mania, alla melancholia, à tutte le oppilationi, à gli hidropici, al trabocco del fiele, et alla milza grossa. Son buoni alla rogna, alla lepra, alle uolatiche, et ad ogni sorte d'ulcerationi fra carne, et pelle, che procedano da gli humori adusti. Nuocono à gli stomachi freddi: et imperò si sminuisce il nocumento loro mescolando con essi, quado si uogliono usare, cose stomachali, come macis, mastice, spica, cassia odorata, et cinnamomo. Sono tardi nell'operare: ma fannosi più uigorosi, dadosi infusi o iin siero di capra, ò in succo di fumoterre, ò in quello di lupoli".
Il Tamarindo è riportato sulla Farmacopea Italiana del 1897, (p.489) ove troviamo: "Pare che non fosse noto agli antichi Romani e Greci, mentre l'uso di questo frutto era antichissimo nelle Indie. il nome di tamarindo proviene dalle parole di origine indica "Tamar hindi", che significa "dattero acido": mentre negli scrittori dellIndia settentrionale del medioevo sono indicati i frutti di tamarindo col nome di "datteri indiani". la conoscenza del tamarindo passò in Europa nel Medio Evo coll'intermezzo degli arabi".
ancora troviamo a riguardo della sua azione terapeutica: "A seconda della
dose può il tamarindo avere azione differente. In piccola quantità
agisce come rinfrescante, a dase alta come purgativo. Era adoperato specialmente
contro la stitichezza che accompagna le malattie febbrili e le affezioni
croniche del fegato. Anche contro la diarrea da indigestione e nel catarro
cronico gastro-enterico avrebbe dato buoni risultati. il cantani lo crede
indicato sopratutto come eccoprotico nei bambini".
Common Names: Tamarind, Tamarindo, Tamarin, Sampalok.
Distant affinity: Carob (Ceratonia siliqua).
Origin: The tamarind is native to tropical Africa and grows wild throughout the Sudan. It was introduced into India so long ago, it has often been reported as indigenous there also. It is extensively cultivated in tropical areas of the world. Sometime during the sixteenth century, it was introduced into America and today is widely grown in Mexico.
Adaptation: The tamarind is well adapted to semiarid tropical conditions, although it does well in many humid tropical areas of the world with seasonally high rainfall. Young trees are very susceptible to frost, but mature trees will withstand brief periods of 28° F without serious injury. A tamarind tree in the Quail Botanical Gardens in San Diego County flowers, but rarely sets fruit, possibly because of the cool coastal climate. Dry weather is important during the period of fruit development. The tree is too large to be grown in a container for any length of time.
Growth Habit: Tamarinds are slow-growing, long-lived, evergreen trees that under optimum conditions can grow 80 feet high with a spread of 20 to 35 ft., in its native eastern Africa and Asia. However, in Southern California it seldom reaches more than 15 to 25 ft. in height.
Foliage: The bright green, pinnate foliage is dense and feathery in appearance, making an attractive shade tree with an open branch structure. The leaves are normally evergreen but may be shed briefly in very dry areas during the hot season. There are usually as many as 10 to 20 nearly sessile 1/2 - 1 inch, pale green leaflets per leaf. The leaflets close up at night.
Flowers: The inconspicuous, inch-wide, five-petalled flowers are borne in small racemes and are yellow with orange or red streaks. The flower buds are pink due to the outer color of the 4 sepals which are shed when the flower opens.
Fruit: The 3 - 8 inch long, brown, irregularly curved pods are borne in abundance along the new branches. As the pods mature, they fill out somewhat and the juicy, acidulous pulp turns brown or reddish-brown. When fully ripe, the shells are brittle and easily broken. The pulp dehydrates to a sticky paste enclosed by a few coarse stands of fiber. The pods may contain from 1 to 12 large, flat, glossy brown, obovate seeds embedded in the brown, edible pulp. The pulp has a pleasing sweet/sour flavor and is high in both acid and sugar. It is also rich in vitamin B and high in calcium. There are wide differences in fruit size and flavor in seedling trees. Indian types have longer pods with 6 - 12 seeds, while the West Indian types have shorter pods containing only 3 - 6 seeds. Most tamarinds in the Americas are of the shorter type.
Location: The tamarind ultimately becomes a fairly large tree, so this should be kept in mind when planting out the tree. It should be planted in full sun and is highly wind-resistant with strong, supple branches. The tree generally forms a beautiful spreading crown that casts a light shade.
Soils Tamarinds tolerate a great diversity of soil types but do best in deep, well drained soils which are slightly acid. Trees will not tolerate cold, wet soils but are tolerant of salt spray and can be planted fairly near the seashore.
Irrigation: The tamarind is adapted to semiarid regions of the tropics and can withstand drought conditions quite well. Young trees require adequate soil moisture until they become established, but mature trees do quite well without supplemental irrigation. Avoid over-watering which results in soggy soils.
Fertilization: The tamarind is not very demanding in its nutritional requirements. Young trees should be fertilized every 2 - 3 months with a 6-6-3 NPK or similar analysis fertilizer. Apply 1/4 lb. and gradually increase to about 1/2 lb. Thereafter, young trees should receive 1/2 lb. per application, per year of tree age, 3 - 4 times a year. Bearing trees can be fertilized with 8-3-9 NPK or similar analysis, at rates of about 1/2 lb. per application per year of tree age. Microelements, particularly iron may be required for trees in alkaline soils.
Pruning: Young trees are pruned to allow three to five well spaced branches to develop into the main scaffold structure of the tree. Maintenance pruning only is required after that to remove dead or damaged wood.
Propagation: Rootstocks are propagated from seed, which germinate within a week. Seeds retain their viability for several months if kept dry. Plant seeds 1/2 inch deep in containers filled with a UC soilless type potting media. They should be selected from trees of good production and quality. Even so, seedlings will be variable in quality and slow to bear. Veneer grafting, shield (T or inverted T) budding and air layering may be used to propagate desirable selections. Such trees will usually fruit within 3 - 4 years if provided optimum growing conditions. Seedlings should begin to produce fruit in 6 - 8 years, while vegetatively propagated trees will normally bear in half that time.
Young trees should be planted in holes larger than necessary to accommodate the root system. They should be planted slightly higher than existing ground level to allow for subsequent settling of the soil and a water basin should be built around each tree to assure adequate moisture for young trees. Spacing of trees is normally 20 to 25 ft. in commercial orchards. However, solitary trees planted in Southern California rarely exceed 15 feet in diameter.
and Diseases: In California tamarinds are generally free of pests and diseases,
although ants will sometimes spread black and olive scales.
In India there are are a host of pests that attack the tree, including mealybugs, caterpillars, aphids, white flies, thrips and a variety of scales. Various weevils and borers can also infest the ripening pods or stored fruits.
Harvest: Tamarind fruits mature in late spring to early summer. They may be left on the tree for as long as 6 months after maturity so that the moisture content will be reduced to 20% or lower. Fruits for immediate processing are often harvested by pulling the pod away from the stalk. Mature trees are capable of producing 350 lb. of fruit a year. Ripe fruit in humid climates is readily attacked by beetles and fungi, so mature fruit should be harvested and stored under refrigeration.
Tamarinds may be eaten fresh, but they area most commonly used with sugar and water in the American tropics to prepare a cooling drink. The pulp is used to flavor preserves and chutney, to make meat sauces ant to pickle fish. Candy can be made by mixing the pulp with dry sugar and molding it into desired shapes.
There are selected cultivars which have sweeter pulp. One in Thailand is Makham Waan and the USDA's subtropical horticulture research unit in Miami, Florida has one called Manila Sweet. None are presently available in Southern California.
Morton, Julia F. Fruits of Warm Climates. Creative Resources Systems, Inc.
1987. pp. 115-121.
Popenoe, Wilson. Manual of Tropical and Subtropical Fruits. Hafner Press. 1974. Facsimile of the 1920 edition. pp. 432-436.
Index of CRFG Publications, 1969 - 1989 and annual indexes of Fruit Gardener
for additional articles on the tamarind.