Formulation and Evaluation of Antimicrobial and Teeth Whitening Polyherbal Dentifrice

Maintaining oral hygiene is essential for overall health. Conventional toothpaste formulations often contain synthetic agents that may cause side effects. In recent years, the focus has shifted towards herbal and natural products due to their safety and therapeutic efficacy. Polyherbal formulations combine multiple plant-derived ingredients to enhance efficacy through synergistic effects. This study aims to formulate and evaluate a polyherbal toothpaste with antimicrobial and whitening properties using tamarind seed, walnut shell, activated charcoal, black seed oil, and clove oil. Oral hygiene plays a critical role in maintaining overall health, as poor oral care can lead to various systemic diseases. Toothpaste is a widely used oral hygiene product, designed to clean teeth, prevent cavities, and combat bad breath. While conventional toothpastes often contain chemical agents such as triclosan and fluoride, concerns about their long-term side effects have driven a growing demand for natural alternatives. In this context, polyherbal formulations have emerged as promising candidates due to their safety, efficacy, and holistic therapeutic properties.

2. MATERIALS AND METHODS

Natural ingredients were selected based on their traditional and scientifically proven roles in oral care. Tamarind seed and walnut shell act as abrasives and antimicrobial agents. Activated charcoal is used for its whitening effect. Black seed oil and clove oil contribute anti-inflammatory and analgesic properties. Additional components such as calcium carbonate, glycerin, sodium lauryl sulphate, and peppermint oil were used for consistency and flavor. The formulation involved combining dry and liquid phases, homogenization, and stability assessment.

Figure: Tamarind Seeds

Formulation Table

The first step is to choose suitable herbal ingredients known for their dental benefits.

The Second Step Is Base Selection:

Formulation trial batches

Evaluation test

1. Organoleptic evaluation

The organoleptic characteristics of the formulated toothpaste were evaluated using various parameters:

• Color: The visual color of the toothpaste was assessed to determine its appearance. This shows the brownish color.
• Odour: The scent of the toothpaste was examined by smelling the product. It has the refreshing and minty aroma.
• Taste: The taste of the formulation was manually checked by tasting it. which is sweet in taste

2. Physicochemical evaluation

1. pH Determination:

The pH determination of polyherbal toothpaste by using Auto pH Meter:

Procedure-

1. Buffer Preparation: Prepare 30 mL of buffer solution for each desired pH by mixing the appropriate volume of stock solutions.
2. Equilibration: Allow the prepared buffer solutions to stand for 15 minutes to reach equilibrium.
3. Sample Preparation: Dissolve the small amount of prepared polyherbal toothpaste in to distilled water for the pH measurement.
4. pH Measurement: Measure the pH of each solution using an auto pH meter according to standard operating procedures.

Figure: pH meter

2. Foamability

1. Weigh or measure 1 gram of the toothpaste using a clean spatula.
2. Transfer the toothpaste into a 10mL graduated cylinder.
3. Add 5mL of distilled water to the cylinder.
4. Mix gently by rotating or tapping the cylinder to ensure the toothpaste is dispersed but not vigorously shaken yet.
5. Allow the cylinder to stand undisturbed for 1 minute so that foam stabilizes

Figure: Foamability

3. Abrasiveness of particles-

The contents were placed on the finger and scratched on the butter paper for about 15-20cm to make sure there were no sharp or abrasive particles present. The same process was carried out for about 8-10 times which detected that there were few traces of small particles of walnut shells powder that were knowingly kept slightly larger than other particles for the good scrubbing of teeth when applied.

4. Grittiness-

Take a small amount of toothpaste (about 0.5–1 g) and spread it between two clean glass slides. Rub gently in a circular motion. Observe for any coarse or gritty particles.

5. Spread ability-

The spread ability test for paste involves assessing its slip and drag characteristics by sandwiching a formulated paste sample between two glass slides:

• 2g of the paste is placed on one glass slide and covered with another, allowing for the expulsion of air and the formation of a uniform film.
• Excess paste is removed, and an 80g weight is applied to the top slide, measuring the time in seconds for the slide to cover a 7.5cm distance.
• Shorter time intervals indicate better spread ability of the paste.

Calculation of spread ability is done using a specific formula, taking into account the time taken for the top slide to move the specified distance.

Calculation- S=M*L/T

Where, S - Spread ability, M - Weight tied to the upper slide

L - Length moved by the glass slide

T -Time (in sec) taken to separate the upper slide from the lower slide.

6. Moisture content

• To determine the amount of moisture and volatile matter in the toothpaste formulation, the researchers followed these steps:
• Placed 5 grams of the formulation in a porcelain dish of specific dimensions. The dish had a diameter of 6-8 cm and a depth of 2-4 cm.
• Dried the sample in an oven at a temperature of 105 degrees Celsius.

Figure: Moisture Content

7. Homogeneity

The section discusses the requirement for toothpaste to maintain homogeneity in its consistency and appearance under specific conditions. The toothpaste should extrude as a uniform mass from either a collapsible tube or another appropriate container when a normal force is applied at 27±2°C.Additionally, the bulk of the toothpaste should extrude smoothly from the container's crimp and then be dispensed steadily.

8. Extrudability

The extrudability of the formulated paste was assessed in the study using a specific method involving aluminum tubes and glass slides. Here is how the extrudability was evaluated: Formulated paste was filled into standard capped collapsible aluminum tubes and sealed by crimping the end. The weights of the tubes were recorded. The tubes were then placed between two glass slides and clamped. A weight of 50g was placed over the slides, following which the cap was removed. The amount of extruded paste was collected, weighed, and used to calculate the percentage of extruded paste.

1. Stability

• The stability study in the research adhered to the guidelines set by the International Conference on Harmonization (ICH). Here are the key details of the stability study: Experimental Setup:
• The formulated paste was filled into collapsible tubes.
• It was then stored under different conditions of temperature and humidity

Table: Stability Evaluation

25ºC ± 2ºC / 60% ± 5% RH

30º C ± 2ºC/ 65% ± 5% RH

40ºC ± 2ºC / 75% ±5% RH

10. Microorganism and inoculation preparation

Gram-positive anaerobic bacteria were found to have antibacterial action. From the Samarth Institute of Pharmacy in Belhe, albicans strains were identified from individuals who had coughed and the S. aureus bacterium is collected from microbiology lab. To determine a concentration for fungal strains and a colony forming unit for bacterial strains, these samples were subcultured and subsequently diluted in a sterile normal saline solution (0.9%), with the turbidity of 0.5 McFarland being adjusted. Grow for 18 to 24 hours at 30 to 37°C in a saline solution while shaking to control turbidity. To inoculate your preferred medium using the cup plate method, use a calibrated pipette or loop.To prevent contamination, always use aseptic method. Label and incubate for up to 24 to 48 hours at the specified temperature, which is typically 30°C or 37°C.

RESULTS

The formulated dentifrice exhibited a brownish color with a smooth texture and characteristic odor. The pH was measured at 6.3, foamability was satisfactory, and moisture content was 15.6%. The toothpaste demonstrated a zone of inhibition of 19.7 mm against Staphylococcus aureus and 12.3 mm against Candida albicans, suggesting good antimicrobial activity. Stability testing confirmed that the formulation remained consistent across various storage conditions.

Physical Examination

Evaluation Results

Comparative study

pH of the formulated toothpaste is compared to the marketed toothpaste (Dant Kanti)

Foamability of the formulated toothpaste is compared to the marketed toothpaste (Dant Kanti)

Spreadability of the formulated toothpaste is compared to the marketed toothpaste (Dant Kanti)