Recent progress in the industrial and biomedical applications of tragacanth gum: A review.

Natural polymers have distinct advantages over synthetic polymers because of their abundance, biocompatibility, and biodegradability. Tragacanth gum, an anionic polysaccharide, is a natural polymer which is derived from renewable sources. As a biomaterial, tragacanth gum has been used in industrial settings such as food packaging and water treatment, as well as in the biomedical field as drug carriers and for wound healing purposes. The present review provides an overview on the state-of-the-art in the field of tragacanth gum applications. The structure, properties, cytotoxicity, and degradability as well as the recent advances in industrial and biomedical applications of tragacanth gum are reviewed to offer a backdrop for future research.

Antifungal activity of oral (Tragacanth/acrylic acid) Amphotericin B carrier for systemic candidiasis: in vitro and in vivo study.

In an effort to increase the oral bioavailability of Amphotericin B (AmB), a pH-sensitive drug carrier composed of Tragacanth (Trag) and acrylic acid (AAc) was prepared using γ-irradiation. The swelling behavior of (Trag/AAc) hydrogels was characterized as a function of pH and ionic strength of the swelling medium. The obtained swelling indices revealed the ability of the prepared hydrogel to protect a loaded drug in stomach-simulated medium (Fickian behavior) and to release such drug in intestinal-simulated medium (non-Fickian behavior). In vitro release studies of the antifungal (AmB) were performed to evaluate the hydrogel potential as a drug carrier. The antifungal activity of the prepared oral formulation was investigated in a mouse model of systemic candidiasis. Data revealed that (Trag/AAc)-AmB has a potent antifungal efficacy as demonstrated by prolonging the survival time and reducing the tissue fungal burden, serum antibody titers, as well as inflammatory cytokines in kidney and liver tissues. Furthermore, in vivo toxicity of (Trag/AAc)-AmB was assessed via measuring kidney and liver functions, and results displayed the safety of this novel AmB formulation which was confirmed by histopathological examination. Overall, results indicated that the prepared (Trag/AAc)-AmB is an effective oral delivery system for AmB with better bioavailability and minimal toxicity and could represent a promising approach for improving the therapeutic index of the drug.

Drug release from enzyme-mediated in situ-forming hydrogel based on gum tragacanth-tyramine conjugate.

In the present study, injectable hydrogels based on gum tragacanth-tyramine conjugate were prepared by enzymatic oxidation of tyramine radicals in the presence of hydrogen peroxide. Then, in vitro release of bovine serum albumin and insulin as model protein drugs from this polymeric network was investigated. Also, to improve the properties of this hydrogel, a blended hydrogel composed of tyramine-conjugated gelatin and tyramine-conjugated tragacanth was prepared. Experimental results showed that the gelation time ranged from 3 to 28 s depending on the polymer and enzyme concentrations. Results of morphological investigation of hydrogels indicated that the average pore size of hydrogels varied from 120 to 160 µm. Swelling degree of hydrogels and the rate of drug release decreased by increasing of hydrogen peroxide and polymer concentrations. The release profile of drug from hydrogels followed Higuchi and Fickian diffusion mechanism. Finally, it was shown that the swelling characteristics and drug release behavior of this polymeric network could be improved by blending it with tyramine-conjugated gelatin.

Design, development and in-vitro evaluation of metoprolol tartrate tablets containing xanthan-tragacanth.

The present study was undertaken to develop oral sustained release tablets of metoprolol tartrate using natural hydrophilic matrix formers (xanthan gum and tragacanth). Sustained release matrix tablets of metoprolol tartrate were prepared by using different ratios of drug, xanthan gum and tragacanth. Microcrystalline cellulose (MCC) was used as diluent. The polymer was incorporated into a matrix system using direct compression technique. All the lubricated formulations were compressed using concave punches in compression machine. Compressed tablets were evaluated for diameter, hardness, friability, weight variation and in vitro dissolution using USP dissolution apparatus-II. Different formulations were evaluated with respect to dissolution profile in 900 mL phosphate buffer (pH 6.8), 0.1 M HCl solution and distilled water for 12 h at 37 degrees C. Increasing the amount of polymer (xanthan gum) in the formulation led to slow release of drug and decreasing the amount of polymer gave enhanced release of metoprolol tartrate. The kinetic treatment showed the best fitted different mathematical models (Zero order, First order, Higuchi's and Hixson-Crowell). Most of the solid matrix formulations followed Higuchi or zero order kinetics. The formulations F1, F2, F3 and F7, F8, F9 showed maximum linearity while the formulations F4, F5, F6 were not of linear behavior. The results showed that the formulation F9 containing 30% xanthan gum and 10% gum tragacanth is the most similar to that of the reference marketed preparation.

Caecal and faecal short-chain fatty acids and stool output in rats fed on diets containing non-starch polysaccharides.

The exact mechanisms by which non-starch polysaccharides increase stool output are unknown. In the present study the hypothesis that the site of fermentation and short-chain fatty acid (SCFA) accumulation is related to the action of non-starch polysaccharides (NSP) on stool output was tested. The basal diet (45 g NSP/kg) of forty-three male Wistar rats was supplemented with 50 g/kg of either guar, karaya, tragacanth, gellan, xanthan or ispaghula for 28 d. A further twenty-three rats were maintained on the basal diet for the same time period. Faeces were then collected over 2 d and caecal contents obtained post-mortem. Caecal and faecal wet and dry weights and SCFA were measured. Each supplement had a different effect on the caecal and faecal contents but they appeared to fall into three groups when compared with the basal diet. In group 1, guar gum affected only caecal SCFA. It had no effect on stool output or faecal SCFA. In group 2, karaya increased caecal SCFA and tragacanth, karaya and xanthan increased faecal SCFA and faecal water. In group 3, ispaghula and gellan had no consistent effect on caecal or faecal SCFA concentrations but increased total faecal SCFA output and increased faecal wet and dry weight. Although the knowledge that SCFA are rapidly absorbed in the large intestine has led us to believe that they play no role in determining faecal output, these results suggest that in some cases where NSP are slowly fermented, and increase faecal SCFA, the role of the SCFA may need to be reassessed.

Lack of carcinogenicity of tragacanth gum in B6C3F1 mice.

Tragacanth gum was administered at dietary levels of 0 (control), 1.25 and 5.0% to groups of 50 male and 50 female B6C3F1 mice for 96 wk after which all animals were maintained on a basal diet without tragacanth gum for a further 10 wk. Mean body weights of females in the 5.0% and 1.25% groups were lower than those of the controls after 11 and 16 wk, respectively. However, there were no treatment-related clinical signs or adverse effects on survival rate, urinalysis, haematology, blood biochemistry and organ weight. While detailed histopathology revealed the development of squamous cell hyperplasias, papillomas and one carcinoma in the forestomach, there was no significant treatment-related increase in the incidence of any preneoplastic or neoplastic lesion. Thus, under the experimental conditions used, tragacanth gum was not carcinogenic in B6C3F1 mice of either sex.

Oral toxicity study of tragacanth gum in B6C3F1 mice: development of squamous-cell hyperplasia in the forestomach and its reversibility.

Tragacanth gum was administered at dietary levels of 0 (control), 0.625, 1.25, 2.5, and 5.0% to groups of 10 male and 10 female B6C3F1 mice for 13 wk. There were no treatment-associated effects regarding clinical signs, body or organ weights, and urinalysis or hematology data. Significant dose-related, but slight, elevations of plasma gamma-glutamyl transpeptidase (GGT) level were observed in all treated animals except the 0.625% females. Single or small numbers of tiny nodules were observed on the luminal surface of the forestomach in 4 males of the 5.0% group, 2 males of the 2.5% group, and 1 male each from the 1.25 and 0.625% groups. Histopathologically, they were diagnosed as squamous-cell hyperplasia. To investigate the nature of these gross lesions, tragacanth gum was fed to groups of 30 male mice at the dietary level of 5.0% for periods of up to 48 wk; 20 males served as controls. There were no treatment-related increases of plasma GGT levels at wk 24 and 48. Although squamous-cell hyperplasias were seen in 2 out of 10 mice at wk 24, none of these proliferative lesions were apparent at wk 48, after either chronic exposure or 24 wk on basal diet. Furthermore, the levels of DNA synthesis in forestomach epithelium as measured by 5-bromo-2-deoxyuridine (BrdU) immunohistochemistry were comparable to control values at wk 24 and 48. Thus, the oral toxicity of tragacanth gum to B6C3F1 mice was concluded to be negligible.

[Study on the repeated oral administration method in infant rats].

The purpose of this study was to establish a new technique for repeated oral administration to infant rats. To determine the maximum volume which could be administered to infant rats the following amounts of the Chinese ink were given by metal gastric zonde for mice: 0.01, 0.04 and 0.08ml/g B. W. General conditions and the arrival distance of the Chinese ink in the gastro-intestinal tract were also observed in infant rats. The best way of administration to infant rats was decided as follows: infant rats were isolated from the dums for one hour before administration and held tenderly by their neck to sustain their mouth upward, then a metal gastric zonde for mice 2 cm long was inserted to their mouth and drug solution was injected slowly. From the observation of general conditions and pathological examination, the maximum volumes for single or repeated administration were considered to be 0.04ml/g B. W. and 0.01 ml/g B. W. respectively. Daily oral administration of 0.1ml/g B. W. of distilled water, 1% CMC solution or 1% tragacantha gum suspension for 44 days caused no effects in infant rats when administration was begun 4 days after birth. These results show that the new method for administration to infant rats is useful to evaluate the toxicity or pharmacological activity of drugs.

Transmission electron microscopy of heart and liver tissues from rats fed with gums arabic and tragacanth.

Transmission electron microscopy has been used to examine the ultrastructure of rat hearts and livers after diet supplementation with (a) 0, 0.5, 1.5, 2.5 and 3.5% (w/w) gum tragacanth (GT) for 91 days, (b) 0 and 1% GT for 5 days (c) 0, 1, 4 and 8% (w/w) gum arabic (GA) for 28 days. The preparation and scrutiny of the electron micrographs was undertaken by two independent teams of specialists. There were no detectable abnormalities in any of the organelles in the heart and liver specimens from any of the test animals and no inclusions nor other pathological changes were observed. All micrographs showed normal, healthy tissues; particular attention was given to the mitochondria in hepatocytes as they serve as sensitive indicators of the health and state of activity of cells. In addition, the data obtained from assays of the microsomal protein and cytochrome P-450 content of the livers showed that GA and GT did not cause inductive effects. These results do not support earlier suggestions, based on in vitro assays, that GA and GT cause changes in the function of rat heart and liver mitochondria and liver microsomes; however, they confirm a report by Zbinden that the ingestion of GT does not produce abnormalities in the cardiac function of rats.

The effects of dietary gum tragacanth in man.

Following a 7-day control period, 5 male volunteers consumed 9.9 g gum tragacanth (GT) daily for 21 days. The GT was well tolerated and there were no adverse effects in any of the volunteers. The daily intake was very high in relation to the minor amounts of GT (estimated at 2 g per person per annum) likely to be ingested as a foodstuffs additive. The wide range of measurements made before and at the end of the test period show that the ingestion of GT had no significant effect on any of the following: plasma biochemistry; haematological indices; urinalysis parameters; glucose tolerance; serum cholesterol, triglycerides and phospholipids; breath hydrogen and methane concentrations. The intestinal transit time decreased and faecal fat concentration increased (P less than 0.01) for 4 subjects. The faecal wet and dry weights increased in all subjects (P less than 0.01). These changes may be of nutritional and physiological interest but do not reflect any adverse toxicological effects arising from the ingestion of large daily doses of GT.