Evaluation of antibiotic potential of alkaloids of Tribulus terrestris L. against some pathogenic microorganisms

Abstract

Context: Antibiotic resistance has become a global concern. There has been an increasing incidence of multiple resistances in human pathogenic microorganisms in recent years, largely due to indiscriminate use of commercial antimicrobial drugs commonly employed in the treatment of infectious diseases. Tribulus terrestris (Family: Zygophyllaceae) is a well-known medicinal plant and has been used world-wide for the treatment of infectious diseases. Alkaloids are group of naturally occurring chemical compounds, which are known to have antimicrobial properties. Aim: The present study is designed to evaluate the antimicrobial potential of alkaloids of T. terrestris L. Materials and Methods: Alkaloids extracted from different parts (root, stem, leaf and fruits) of T. terrestris were screened by Disc diffusion assay against three bacterial strains: gram positive (Staphylococcus aureus), gram negative (Escherichia coli and Proteus mirabilis) and two fungal strains: Aspergillus flavus and Aspergillus niger. Minimum inhibitory concentration of the extracts was evaluated by micro broth dilution method while minimum bactericidal/fungicidal concentration was determined by sub culturing the relevant samples. Total activity of the extracts against each sensitive test pathogens was also calculated. Statistical Analysis: Mean value and standard error mean were calculated for the results of disc diffusion assay and data were analysed by one-way analysis of variance and P values were considered significant at P < 0.05. Results: The alkaloid extracts of T. terrestris showed significant antibacterial potential as all test extracts were found active against both the gram positive and negative bacteria, but were inactive against the tested fungi. Conclusion: The present study indicates the broad spectrum antibacterial potential of the alkaloids of T. terrestris, hence may be exploited for future antibacterial drugs.

A Comprehensive Review of the Phytochemical, Pharmacological, and Toxicological Properties of Tribulus terrestris L.

“…There are several in vitro studies that have revealed the antibacterial potency of TT total or fractionated extracts on Gram-negative and Gram-positive bacterial strains. Among the Gram-positive bacteria, facultative anaerobe strains such as Staphylococcus aureus, Streptoccocus mutans, Streptococcus sanguinis, Actinomyces viscosus, Enteroccocus faecalis, and Bacillus subtilis were susceptible and among the Gram-negative bacteria Escherichia coli, Salmonella typhi, Proteus mirabilis, and Klebsiella pneumoniae were susceptible [87][88][89][90][91][92]. It is still unclear which components are responsible for the antibacterial activity, but alkaloids contribute to the general antibacterial effect of the total extracts [88].…”

“…Among the Gram-positive bacteria, facultative anaerobe strains such as Staphylococcus aureus, Streptoccocus mutans, Streptococcus sanguinis, Actinomyces viscosus, Enteroccocus faecalis, and Bacillus subtilis were susceptible and among the Gram-negative bacteria Escherichia coli, Salmonella typhi, Proteus mirabilis, and Klebsiella pneumoniae were susceptible [87][88][89][90][91][92]. It is still unclear which components are responsible for the antibacterial activity, but alkaloids contribute to the general antibacterial effect of the total extracts [88]. The antibacterial effects of saponins are well documented and the mechanism of action is based on the destruction of the cell membrane, leading to cell death (bactericidal effect), probably due to their amphiphilic nature and their surfactant properties.…”

Staphylococcal Enterotoxin A Gene–Carrying Staphylococcus aureus Isolated from Foods and Its Control by Crude Alkaloid from Papaya Leaves

“…MIC of cmde alkaloid to S. aureus in this study was lower than MIC of ethanolic extract of papaya leaves found by Rahman et al (31), i.e., in a concentration of 1.25 mg/ml. This crude alkaloid MIC was also lower than the crude alkaloid extract from Tribulus terrestris leaves against S. aureus that was in a concentration of 0.625 mg/ml (16). On the other hand, a MIC of papaya leaf crude alkaloid extract was higher than that of the alkaloid extract from Aconitum elwesii and Sida acuta Burm.…”

Promising phytopharmacology, nutritional potential, health benefits, and traditional usage of Tribulus terrestris L. herb

“… [ 7 , 35 ] 5 Flavonoids (Kaempferol-3-glucoside Tribuloside, Kaempferol, and Kaempferol-3-rutinoside Fruit Aphrodisiac Diuretic, Anti-spasmodic and Antioxidant [ 99 , 138 ] 6 Alkaloids (Tribulusterine, Tribulusamide, Tribulusin, Harmine, Harmmol, Terrestriamide and Terrestribisamide, Fruit Antibacterial Antioxidant and Aphrodisiac. [ 84 , 139 ] 7 Saponins, Phytosterols, Rutin, Tannins, Protodioscin, Tannins, Arginine, Carbohydrates, β-carboline Alkaloid and Tribulusin, Stem Immunomodulatory effects, Anti-Spasmodic and Antioxidant, [ 7 ] 8 Tribulus Terrestris roots have entirely reducing sugar properties; Flavonoids, Saponins, alkaloids, Triterpenoids, Xanthoprotein, and Unique phenolic compounds are phenol 2-(5,6-dimthyl pyrazinyl), and Histidine. Root Aphrodisiac, Ant- bilious, and Antidiabetic.…”