Hydroalcoholic Leaf Extract of Punica granatum, alone and in Combination with Calcium Hydroxide, Is Effective against Mono- and Polymicrobial Biofilms of Enterococcus faecalis and Candida albicans

Effect of pomegranate solution alone or combined with chlorhexidine against oral multispecies biofilm

AIM

Natural bioactive products have been tested as alternative antimicrobial agents. This study evaluated the effect of Punica granatum extract (PGE) on oral multispecies biofilms.

METHODOLOGY

Lyophilized extracts from pomegranate peel were prepared, and the punicalagin content was assessed by ultra-performance liquid chromatography (UPLC). Oral multispecies biofilms from 2 donors were grown on four collagen-coated hydroxyapatite discs. After incubation for 7 days or 3 weeks, the biofilms were exposed to water (control), 2% CHX, 10% PGE, 20% PGE or 30% PGE for 3 min. The proportions of dead bacteria were assessed by the live/dead staining and confocal microscopy. After the analysis, the best PGE concentration (30%) was combined with CHX. The experimental phases were repeated using water, 2% CHX, 30% PGE and 30% PGE + 2% CHX. Five random areas of the biofilm on each disc were scanned, resulting in 20 scanned areas for each group.

RESULTS

Regarding the biofilm volume, no differences were found amongst solutions (p = .111). The PGE solution killed bacteria effectively in 1-week, 2-week and 3-week-old-plaque biofilms, ranging from 37 to 55.3%, depending on the PGE concentration. The 30% PGE (a) (p = .0009) had greater antibiofilm effectiveness than 2% CHX (b), which killed bacteria in the 25.2 to 48.7% range. The 10% and 20% PGE had intermediate values (ab), without significant differences from 30% PGE (p = 1.002). Water (c) had the lowest proportion of dead bacteria (p < .00001) in a range of 5 to 6.7% and lower effectiveness in killing bacteria (p < .05). The PGE alone or mixed with 2% CHX had greater anti-biofilm effectiveness than CHX (p < .05). The old plaque biofilms were more resistant than the 7-day-old plaque (p < .05).

CONCLUSIONS

The 30% PGE (alone or combined with CHX) exhibited a greater antibiofilm effect on oral multispecies biofilms grown on hydroxyapatite discs than 2% CHX.

Synergistic antibacterial effect of ginsenoside Rh2 and calcium hydroxide on Enterococcus faecalis

Treatment of root canal infections becomes more challenging due to the extremely high tolerance of Enterococcus faecalis (E. faecalis) to calcium hydroxide (Ca(OH)2). Ginsenoside is a Chinese herbal extract that has been proven to have antimicrobial properties and synergistic activities. And this study evaluated the antibacterial activity of ginsenoside Rh2 in combination with Ca(OH)2 against E. faecalis and its preliminary mechanism of action. Broth microdilution method, checkerboard dilution method, time-inhibition curve, drug resistance assays, scanning electron microscopy, and biofilm inhibition and removal assays indicated that Rh2 in combination with Ca(OH)2 exhibited potent antibacterial activity against E. faecalis. Rh2 exerted significant in vitro antibacterial activity against E. faecalis, with a minimum inhibitory concentration (MIC) of 3.125 μg/mL and minimum bactericidal concentration (MBC) of 6.25 μg/mL, and significantly enhanced the susceptibility of E. faecalis to Ca(OH)2 (FICI = 0.5). Furthermore, cell membrane permeability assays, surface hydrophobicity assays, ATPase activity assays, and intra-biofilm extracellular polysaccharides (EPS) assays revealed that Rh2 and Ca(OH)2 synergistically inhibit bacteria mainly by increasing membrane permeability. Ultimately, cytotoxicity assays showed that Rh2 exhibited only low toxicity, the half maximal inhibitory concentration (IC50) of Rh2 was 19.75 μg/mL. This study confirmed the synergistic antibacterial activities of Rh2 and Ca(OH)2 against E. faecalis. Our findings indicate that the Rh2 and Ca(OH)2 combination may be a promising alternative approach to treating root canal infections.

Characterization, Antimicrobial Activity, and Antioxidant Efficacy of a Pomegranate Peel Solution Against Persistent Root Canal Pathogens

BACKGROUND

The limitations of dental irrigation solutions reinforce the need to explore novel bioactive compounds that are safer and biodegradable. This study aimed to prepare a 10% pomegranate peel solution (Punica granatum extract - PGE) and evaluate its antimicrobial and antioxidant effects for root canal treatment.

METHODS

Lyophilized extracts (1g/10 mL) from pomegranate peels were prepared, and the punicalagin content was assessed by ultra-performance liquid chromatography using pure punicalagin (standard). The antimicrobial activity was tested against common persistent root canal pathogens by the agar diffusion method, minimum inhibitory concentration (MIC), and minimum bactericidal/fungicide concentration (MCB/MFC). The antioxidant activity (%AA) was assessed by the DPPH radical scavenging method. Data were analyzed by ANOVA and Tukey's test (α = 0.05).

RESULTS

The total phenolic content of the PGEextract was 6.55 µg/mL. Differences were found among the inhibition zone of PGE (23.32 ± 3.65), 1% NaOCl (30.76 ± 4.73), and 50% ethanol (without inhibition) (p < 0.05). The MIC values of PGE ranged between 6.25 and 75 mg/ml, and PGE was effective against the tested pathogens. PGE had antioxidant potential (IC50 = 3.52 µg/mL); however, the mean values were inferior to that of the quercetin (positive control) (IC50 = 0.95 µg/mL). The DPPH scavenging effect (%AA) of PGE (70.98 ± 2.3) had no difference from the positive control (72.94 ± 2.1) (p = 0.253).

CONCLUSION

The PGE extract was successfully biosynthesized and exhibited antimicrobial and antioxidant activity, suggesting its potential use as an adjuvant therapy during root canal treatment.

Evaluation of the topical gel and oral administration of Punica Granatum Var Pleniflora on oral mucositis induced by 5-Fluorouracil in golden hamsters

BACKGROUND

Oral mucositis (OM), an acute inflammation of the oral cavity, is a common complication in patients undergoing invasive myeloblastic chemotherapy or radiation therapy. 5-fluorouracil (5-FU) is one of the most effective therapeutic drugs, but one of the common side effects of 5-FU administration is OM. Unfortunately, no suitable treatment has been found, so far to control its side effects. Studies showed that herbal medicine like Punica granatum var pleniflora (PGP) has medicinal properties such as anti-inflammatory and antibacterial and can be an alternative for the treatment of fungal infection. Accordingly, we decided to investigate the therapeutic effect of PGP in the treatment of OM caused by 5-FU in golden hamsters.

METHODS

Sixty male golden hamsters were divided into six main group. Chemotherapy with 5-FU at dose of 60 mg/kg was performed at a ten-day duration. Then, cheek pouches of the hamsters were scratched with an 18-gauge sterile needle to induce oral mucositis in animals. On the twelfth day, as a day of intensification of OM, treatment with PGP including topical gel with concentrations of 5% and 10% and oral administration of hydro-alcoholic extract with doses of 125 mg/kg and 250 mg/kg for three- and five-day therapeutic duration were separately started. Finally, samples of cheek pouches in hamsters were collected on 14th and 17th days and histopathologic score (HPS), malondialdehyde (MDA), and myeloperoxidase (MPO) levels were assayed.

RESULTS

A significant (p < 0.05) decrease in histopathologic score was observed in G_10%-, P₁₂₅-treated groups in comparison to the Ctrl group. Our data showed that treatment with G_10% is more potent than P₁₂₅-treated group. In contrast, histopathologic score in G_10%, P₁₂₅, and P₂₅₀ treated groups demonstrated almost similar values On the 17th day. However, the levels of MDA and MPO in the treatment groups were enhanced compared with control group (p < 0.05).

CONCLUSIONS

It is possible that PGP can play protective role in the healing of tissue damage caused by chemotherapy with 5-FU due to the presence of its natural compounds and antioxidant properties.

Valorization of Punica granatum L. Leaves Extracts as a Source of Bioactive Molecules

Due to a lack of innovative valorization strategies, pomegranate processing generates a significant amount of residues with a negative environmental footprint. These by-products are a rich source of bioactive compounds with functional and medicinal benefits. This study reports the valorization of pomegranate leaves as a source of bioactive ingredients using maceration, ultrasound, and microwave-assisted extraction techniques. The phenolic composition of the leaf extracts was analyzed using an HPLC-DAD-ESI/MSn system. The extracts’ antioxidant, antimicrobial, cytotoxic, anti-inflammatory, and skin-beneficial properties were determined using validated in vitro methodologies. The results showed that gallic acid, (-)-epicatechin, and granatin B were the most abundant compounds in the three hydroethanolic extracts (between 0.95 and 1.45, 0.7 and 2.4, and 0.133 and 3.0 mg/g, respectively). The leaf extracts revealed broad-spectrum antimicrobial effects against clinical and food pathogens. They also presented antioxidant potential and cytotoxic effects against all tested cancer cell lines. In addition, tyrosinase activity was also verified. The tested concentrations (50–400 µg/mL) ensured a cellular viability higher than 70% in both keratinocyte and fibroblast skin cell lines. The obtained results indicate that the pomegranate leaves could be used as a low-cost source of value-added functional ingredients for potential nutraceutical and cosmeceutical applications.

Pomegranate: A review of the heavenly healer's past, present, and future

In the great Persian Empire, pomegranate (Punica granatum L.) had a wide reputation for use both as an herbal medicine and nutritious food. It was also a symbol of peace and love according to Achaemenid limestones in the great Persia. This paper aims to review the traditional uses of pomegranate in Persian and Islamic traditional medicine and have thorough and current information regarding the pharmacology and phytochemistry of this valuable plant for practical use and further research. Relevant information about P. granatum was collected from scientific publishers and databases including Elsevier, Wiley, PubMed, and Google Scholar between 1950 and 2022. The traditional knowledge was extracted from Persian and Islamic traditional textbooks. Based on traditional textbooks, pomegranate has beneficial effects on diseases related to gastrointestinal, upper and lower respiratory, visual, and reproductive systems. In addition, pomegranate and its preparations have been prescribed for treating metabolic disorders, skin problems, and wounds as well as dental protection. Preclinical and clinical evidence supports many therapeutic potentials of pomegranate in traditional medicine. Its therapeutic effects are mostly attributed to its polyphenols. The knowledge in Persian and Islamic traditional textbooks about pomegranate and its preparations can be used as a guide for further preclinical and mainly clinical studies to discover the therapeutic potential of this valuable plant.

Punica granatum as Anticandidal and Anti-HIV Agent: An HIV Oral Cavity Potential Drug

The oral cavity is crucial from diagnosis to adherence to HAART therapy in the HIV/AIDS population; consequently, drugs that can maintain healthy conditions in the oral cavity are necessary for patients with HIV/AIDS. Punica granatum (pomegranate) is a tree that has been employed extensively for centuries in the traditional medicine of ancient cultures for the treatment of a wide range of diseases, including oral and dental diseases. In recent decades, its potent anticandidal properties have been shown, especially on Candida albicans, the cause of the most common clinical manifestation in HIV patients. The present work contributes to the review of the anti-HIV and anticandidal properties of the plant species P. granatum as involved with the oral cavity. The literature reviewed revealed that crude extracts of pomegranate and its main isolated compounds possess inhibitory activity on different HIV targets, including binding viral proteins and the three replicative HIV enzymes. In addition, in the literature reviewed, pomegranate exhibited anticandidal effects on 10 different species. Thus, pomegranate appears to be an excellent candidate to explore and incorporate into the treatment of the oral cavity of HIV/AIDS patients, in that, in addition to its pharmacological effects such as antiviral and anticandidal, pomegranate represents an easily available, inexpensive, and safe natural source.