Antimicrobial Efficacy of Various Essential Oils at Varying Concentrations against Periopathogen Porphyromonas gingivalis

Susceptibility of periodontal pathogens to a novel target-specific drug delivery system containing self-nanoemulsifying curcumin: An in vitro study

Background

Long-term use of many classic chemotherapeutic agents as adjuncts in the management of periodontitis has adverse complications, leading to seeking out naturopathic remedies. Although curcumin has been investigated in managing periodontitis, its therapeutic benefits have not been fully explored due to its limited solubility in an aqueous medium. This study aimed to develop a novel target-specific drug delivery system containing 1% self-nanoemulsifying curcumin (SNEC) in a hydroxypropylmethylcellulose (HPMC) matrix and evaluate the susceptibility of periodontal pathogens to this system in vitro.

Methods

Its antibacterial activity against Tannerella forsythia, Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans was evaluated and compared to pure nano-curcumin and SNEC alone by estimating their minimum inhibitory concentrations (MIC).

Results

The antibacterial activity of pure nano-curcumin, SNEC, and SNEC in HPMC against the four periodontal pathogens evaluated in terms of MIC was recorded in the range of 0.2‒0.4, 0.4‒0.8, and 0.2‒0.8 µg/mL, respectively. However, the MIC of all three curcumin formulations against the periodontal pathogens tested was higher than that of the standard moxifloxacin. While both pure nano-curcumin and SNEC showed increasing values of inhibition zones with increasing concentrations on disk diffusion assay, lower concentrations of SNEC in HPMC did not show a zone of inhibition against the tested pathogens.

Conclusion

The novel delivery system containing SNEC in HPMC may be a potential adjunct in managing periodontitis due to its probable sustained antimicrobial activity against the tested periodontal pathogens.

The Effect of Nonnutritive Sweeteners on the Antimicrobial Activity of Eucalyptus Extracts against Salivary Mutans Streptococci (in-vitro Study)

The eucalyptus tree is an excellent source of antimicrobial agents; it is used in many oral cure products. The bitter taste of these agents could compromise their usage. Therefore, fortifying the extracts with non-nutritive sweeteners could be a promising procedure for masking their unpleasant taste. This study was an in vitro evaluation of the antimicrobial activity of eucalyptus (alcoholic and aqueous) extracts against salivary Streptococci mutans. It aimed to investigate the effect of non-nutritive sweeteners on the antimicrobial activity of these extracts against salivary S. mutans. The test microbes were sensitive to different concentrations of eucalyptus alcoholic and aqueous extract, and the inhibition zone increased as the concentration of the extracts increased. All the Mutans isolates were killed at a concentration of 75 mg/ml for the alcoholic extract and 175 mg/ml for the aqueous extracts. In this experiment, the concentration of up to 15% stevia and up to 5% sucralose did not affect the antimicrobial activity of eucalyptus alcoholic extract. While the concentration of up to 1% of stevia and sucralose did not interfere with the antimicrobial activity of aqueous eucalyptus extract against salivary S. mutans. An increase in the concentration of non-nutritive sweeteners in this experiment appeared to interfere with the antimicrobial activity of eucalyptus extract against salivary S. mutans.

Pharmacological Profile, Bioactivities, and Safety of Turmeric Oil

The pharmacological attributes of turmeric have been extensively described and frequently related to the action of curcuminoids. However, there is also scientific evidence of the contribution of turmeric oil. Since the oil does not contain curcuminoids in its composition, it is crucial to better understand the therapeutic role of other constituents in turmeric. The present review discusses the pharmacokinetics of turmeric oil, pointing to the potential application of its active molecules as therapeutic compounds. In addition, the bioactivities of turmeric oil and its safety in preclinical and clinical studies were revised. This literature-based research intends to provide an updated overview to promote further research on turmeric oil and its constituents.

Antimicrobial Activity of Eucalyptus globulus, Azadirachta indica, Glycyrrhiza glabra, Rheum palmatum Extracts and Rhein against Porphyromonas gingivalis

Novel plant-derived antimicrobials are of interest in dentistry, especially in the treatment of periodontitis, since the use of established substances is associated with side effects and concerns of antimicrobial resistance have been raised. Thus, the present study was performed to quantify the antimicrobial efficacy of crude plant extracts against Porphyromonas gingivalis, a pathogen associated with periodontitis. The minimal inhibitory concentrations (MICs) of Eucalyptus globulus leaf, Azadirachta indica leaf, Glycyrrhiza glabra root and Rheum palmatum root extracts were determined by broth microdilution for P. gingivalis ATCC 33277 according to CLSI (Clinical and Laboratory Standards Institute). The MICs for the E. globulus, A. indica and G. glabra extracts ranged from 64 mg/L to 1024 mg/L. The lowest MIC was determined for an ethanolic R. palmatum extract with 4 mg/L. The MIC for the anthraquinone rhein was also measured, as the antimicrobial activity of P. palmatum root extracts can be partially traced back to rhein. Rhein showed a remarkably low MIC of 0.125 mg/L. However, the major compounds of the R. palmatum root extract were not further separated and purified. In conclusion, R. palmatum root extracts should be further studied for the treatment of periodontitis.

Can Plant Materials Be Valuable in the Treatment of Periodontal Diseases? Practical Review

Periodontal diseases are one of the most significant challenges in dental health. It is estimated that only a few percent of the worldwide population have entirely healthy teeth, and according to WHO, oral diseases may affect up to 3.5 billion people worldwide. One of the most serious oral diseases is periodontitis, an inflammatory disease affecting periodontal tissues, caused by pathogenic bacteria and environmental factors such as the ageing population, abuse of tobacco products, and lack of adequate oral hygiene due low public awareness. Plant materials are widely and successfully used in the management of many conditions, including periodontitis. Plant materials for periodontitis exhibit antibacterial, anti-inflammatory, antioxidant activities and affect the periodontium structure. Numerous studies demonstrate the advantages of phytotherapy for periodontitis relief and indicate the usefulness of Baikal skullcap root, Pomegranate fruit peel and root cortex, Tea leaves, Chamomile flowers, Magnolia bark, Blackberry leaves and fruits, Cranberry fruits and Lippia sidoides essential oil. This review aims to analyze the use and applicability of selected plant materials in periodontitis management since it is of paramount importance to evaluate the evidence of the traditionally used plant materials in light of continuously growing interest in phytotherapy and its adjuvant role in the treatment of periodontitis.

Effectiveness of Oil-Based Denture Dentifrices-Organoleptic Characteristics, Physicochemical Properties and Antimicrobial Action

Denture dentifrices must be effective and not deleterious to prosthetic devices. This study formulated and evaluated dentifrices based on oils of Copaifera officinalis, Eucalyptus citriodora, Melaleuca alternifolia, Pinus strobus, and Ricinus communis. Organoleptic characteristics (appearance, color, odor, taste), physicochemical properties (pH, density, consistency, rheological, abrasiveness, weight loss, and surface roughness) and antimicrobial (Hole-Plate Diffusion–HPD)/anti-biofilm (Colony Forming Units–CFU) action against Staphylococcus aureus, Streptococcus mutans, and Candida albicans were evaluated. Formulations were compared with water (negative control) and a commercial dentifrice (positive control). The data were analyzed by Kruskal-Wallis and Dunn tests (α = 0.05). The organoleptic and physicochemical properties were adequate. All dentifrices promoted weight losses, with high values for C. officinalis and R. communis, and an increase in surface roughness, without differing from each other. For antimicrobial action, C. officinalis and E. citriodora dentifrices were similar to positive control showing effectiveness against S. mutans and C. albicans and no dentifrice was effective against S. aureus; regarding the anti-biofilm action, the dentifrices were not effective, showing higher CFU counts than positive control for all microorganisms. The dentifrices presented satisfactory properties; and, although they showed antimicrobial action when evaluated by HPD, they showed no effective anti-biofilm action on multispecies biofilm.

The hydroxyl moiety on carbon one (C1) in the monoterpene nucleus of thymol is indispensable for anti-bacterial effect of thymol

Background

Thymol, a natural monoterpene phenol is not only relevant clinically as an anti-microbial, anti-oxidant and anti-inflammatory agent but also holds the prospect as a natural template for pharmaceutical semi-synthesis of therapeutic agents. It is a major component of essential oils from many plants. Evidence abound linking overall bioactivity of thymol to its monoterpene nucleus, specifically, the hydroxyl (-OH) substituent on carbon number one (C1) on the monoterpene nucleus. Other studies have posited that the overall bioactivity of thymol is not substantially altered by chemical modification of - OH on the C1 of the monoterpene nucleus. In view of this, it is still unclear as to whether removal or modification of the –OH on C1 of the monoterpene nucleus relates generally or context-dependently to bioactivity of thymol.

Objective

The present study investigated anti-bacterial effects of ester-and-ether substituted derivatives of thymol on S. aureus, P. aeruginosa and E. coli.

Materials and methods

twelve ester-and-ether substituted derivatives of thymol (6TM1s and 6TM2s) were synthesized and characterized by using HPLC, Mass spectrometry, and IR techniques. Anti-bacterial activity of the 12 thymol derivatives was evaluated using broth macrodilution and turbidimetric methods against pure clinical isolates (S. aureus, P. aeruginosa and E. coli). Standard anti-biotics used were Thymol Streptomycin and flucloxacillin, while DMSO was used as vehicle for thymol derivatives. MIC and MBC were determined.

Results

Thymol produced broad-spectrum growth inhibition on all isolates. At equimolar concentrations, thymol and reference drugs produced concentration-dependent growth inhibition against the isolates (Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli) compared to DMSO. Although the growth inhibitory effects of the ester-and-ether derivatives of thymol was significant (P ≤ 0.05) compared to DMSO, it was however insignificant (P ≥ 0.05) compared to thymol and reference antibiotics. Comparatively, at equimolar concentrations, ester-substituted derivatives of thymol, particularly the branched chain derivative (TM1C) produced more effective growth inhibition on the isolates than the ether-substituted derivatives of thymol. Thymol was twice as potent (MIC and MBC, 500 μg/ml) than both ester-and-ether substituted derivatives of thymol (MIC and MBC, > 1000 μg/ml) on all the three clinical isolates. Increase in side chain bulkiness of –OH moiety on the monoterpene nucleus of thymol decreased growth inhibition on isolates.

Conclusion

Thymol has demonstrated broad-spectrum anti-bacterial effects attributable to the hydroxyl moiety on C1 of the monoterpene nucleus. Structural modification of the hydroxyl moiety on C1 of the monoterpene nucleus of thymol with either ether-or-ester substitutions yielded no significant anti-bacterial effects.

Antibacterial Effect of Curcumin against Clinically Isolated Porphyromonas gingivalis and Connective Tissue Reactions to Curcumin Gel in the Subcutaneous Tissue of Rats

The aim of this study was to find the antibacterial potential of curcumin against Porphyromonas gingivalis and connective tissue responses to curcumin gel in the subcutaneous tissue of rats. The sample consisted of subgingival plaque collected from patients with chronic periodontitis. The P. gingivalis clinically isolated strain was confirmed by anaerobic culture, morphology, biochemical tests (Vitek ANC Kit), and PCR (16S rDNA). Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by incubation of twofold serial dilution of broth media containing curcumin (from 100 to 0.05 µg/ml) for 48 h at 37°C. Fifteen adult Wistar rats (3-4 months old) were used and randomly divided into three groups (negative control, positive control, and experimental groups). Tubes were implanted on the back skin (45 tubes). Rats were euthanized at 7, 30, and 60 days after surgical processes, and then the samples were taken and processed to achieve conventional hematoxylin and eosin-stained slides. The MIC and MBC of curcumin against clinically isolated P. gingivalis were 12 µg/ml. Curcumin gel caused moderate inflammatory reactions at 7 and 30 days, while at 60 days, it caused dramatic decline and resulted in a nonsignificant response. Besides, curcumin gel stimulated quick reepithelialization, fibroblast proliferation, and scarring through the formation of thick bundles of well-organized collagen fibers. Curcumin has an effective antibacterial action against clinically isolated P. gingivalis at low concentration (12 µg/ml), and it was regarded as the biocompatible material in the subcutaneous tissues.

Evaluation of Antibacterial Effect against Porphyromonas gingivalis and Biocompatibility of Essential Oil Extracted from the Gum of Pistacia atlantica Kurdica

OBJECTIVE

This study investigates the antibacterial effect of essential oil extracted from the gum of Pistacia atlantica Kurdica against Porphyromonas gingivalis and histological evaluation of an experimental gel of the extract in wound healing in the back subcutaneous tissue of Wistar rats.

METHODS

Clinical strains of bacteria obtained from subgingival plaque samples of individuals having periodontitis, isolation, and confirmation were done by conventional microbiological tests and molecular technique. Essential oil was extracted by using hydrodistillation method; antibacterial activity has been determined by two fold serial dilution method. Histological evaluation conducted on fifteen Wistar rats. Incisions were made on the dorsal surface of each animal for implanting of 3 polysilicone tubes (empty, tetracycline gel, and the experimental gel). After 1, 4, and 8 weeks, the animals were euthanized and the specimens were prepared histologically.

RESULT

The extract demonstrated antimicrobial effect and significant wound healing in the different study durations particularly our product showed progression in epidermal wound healing and decrease in cellularity and scoring of inflammatory cells.

CONCLUSION

The extract was able to pose inhibitory and bactericidal activity against P. gingivalis and the experimental gel was able to have a good wound healing that enable it to be considered as a compatible material.

The Antiplaque Efficacy of Two Herbal-Based Toothpastes: A Clinical Intervention

Aims

This study is the first of its kind in the United Arab Emirates, where these herbal plant extracts are commonly incorporated into toothpaste. The present study compares two herbal toothpastes (Meswak extract and tea tree oil [TTO]) and analyses their efficiency in reducing plaque accumulation.

Materials and Methods

A total of 25 patients were examined for plaque and assigned a plaque score. They were then randomly assigned to use either Meswak-based toothpaste or TTO-based toothpaste. After 24 h, a new plaque score was recorded, and the patients used their regular brand for 2 weeks. The patients were then instructed to use the second of the two study toothpastes for 24 h, and a third set of plaque scores was obtained. Statistical data were analyzed using the SPSS software with a significance of P < 0.05 and Kruskal-Wallis test.

Results

Analysis of plaque scores showed a reduction in plaque index after using either of the two herbal-based toothpastes; however, when compared with TTO, Meswak-based toothpaste resulted in significantly less plaque.

Conclusions

Brushing with Meswak-based toothpaste gave a significant drop in plaque score when compared with TTO-based paste.