Antibacterial, antifungal, antibiofilm, and cytotoxicity activity of Astragalus baba-alliar extract against main causes of dental root canal infections

Document Type : Original Articles

Authors

1 Razi Herbal Medicines Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran.

2 Department of Endodontics, School of Dentistry, Lorestan University of Medical Sciences, Khorramabad, Iran.

3 Student Research Committee, School of Dentistry, Lorestan University of Medical Sciences, Khorramabad, Iran.

4 Department of Dental Biomaterials, Faculty of Dentistry, Lorestan University of Medical Sciences, Khorramabad, Iran.

5 Department of Electronic Engineering, Universitat Rovira i Virgili, 43007, Tarragona, Spain.

6 Razi Herbal Medicines Research Center, Student Research Committee, School of Dentistry, Lorestan University of Medical Sciences, Khorramabad, Iran.

10.22092/ari.2024.365789.3139

Abstract

The objective of endodontic treatment is paramount: to completely eradicate bacterial infection within the dental pulp and root canal system. This study aimed to evaluate the Antimicrobial, antibiofilm, and cytotoxicity activity of Astragalus baba-alliar (A. baba-alliar) extract against the main causes of dental root canal infections (Enterococcus faecalis and Candida albicans). After the preparation of the methanolic extract from A. baba-alliar, phytochemical analysis was conducted to determine the content of secondary metabolites, followed by the determination of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) against Candida albicans (C. albicans) and Enterococcus faecalis (E. faecalis). Subsequently, the ability of the methanolic extract to inhibit biofilm formation was investigated using the microtiter plate method. The cytotoxic effects of the methanolic extract on normal human gingival fibroblast cells (HGF1) and oral cancer cells (KB) were evaluated using the MTT reduction method. Based on the phytochemical results, the presence of flavonoids, terpenoids, saponins, and polysaccharides in this plant extract was confirmed. The total phenol and flavonoid content were determined to be 4.23 mg GEA/g DW and 2.61 mg QE/g DW, respectively. The methanol extract of the plant, both alone and in combination with nystatin, exhibited a significant anti-candidal effect against C. albicans, while alone and especially in combination with chlorhexidine, it demonstrated a significant antibacterial effect against E. faecalis. Moreover, the extract alone and in combination with nystatin induced biofilm formation in C. albicans with an MBIC50 of 4.6 μg/ml, 64 μg/ml, and 0.25 μg/ml, respectively. Similarly, the extract alone and combined with chlorhexidine inhibited biofilm formation in E. faecalis with a Minimum biofilm inhibitory concentration (MBIC50) of 42.6 μg/ml and 1.16 μg/ml, respectively. The calculated Selectivity Index (SI) exceeding 2 (SI=2.72) indicates the extract's selective cytotoxicity towards cancer cells while maintaining negligible toxicity towards normal. Based on the antimicrobial properties uncovered in this research, the study is anticipated to lay the groundwork for clinical trials and subsequent investigations into the plant's effective compounds. Such endeavors hold potential for application across various industrial sectors including food, pharmaceuticals, and medicine.

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