Formulation, Standardization and Evaluation of a Polyherbal Cough Syrup Containing Cyperus Rotundus, Piper Longum, Glycyrrhiza Glabra, Zingiber Officinale and Emblica Officinalis

Cough is a protective physiological reflex that facilitates the removal of mucus, foreign particles, and irritants from the respiratory tract. Although cough serves an essential protective function, persistent coughing can adversely affect quality of life and may indicate underlying respiratory disorders. Conventional cough medications frequently produce adverse effects such as drowsiness, dizziness, gastrointestinal discomfort, and dependency. Medicinal plants have been employed for centuries in traditional systems of medicine, including Ayurveda, Siddha, and Unani, for the treatment of respiratory disorders. Recent interest in herbal medicines has increased due to their natural origin, affordability, accessibility, and lower risk of adverse reactions. Piper longum possesses expectorant and bronchodilator activities, while Glycyrrhiza glabra exhibits demulcent and anti-inflammatory properties. Zingiber officinale contains bioactive compounds such as gingerols and shogaols that provide antimicrobial and anti-inflammatory effects. Emblica officinalis is rich in vitamin C and antioxidant compounds that enhance immunity and protect against oxidative stress. Cyperus rotundus contributes antimicrobial and anti-inflammatory activities. Honey serves as a natural preservative and soothing agent, whereas lemon oil improves flavor and aroma. The present investigation was undertaken to develop and evaluate a stable polyherbal cough syrup utilizing these medicinal herbs.

MATERIALS AND METHODS

MATERIALS

The ingredients used in the formulation are listed below.

Table 1. Composition of Polyherbal Cough Syrup

2.2 Preparation of Herbal Extracts

The plant materials were collected, authenticated, cleaned, shade-dried, and powdered. Suitable aqueous extraction procedures were employed for each herb. The extracts were filtered and stored under refrigerated conditions until further use.

2.3 Preparation of Syrup Base

A syrup base was prepared by dissolving sugar in purified water under controlled heating with continuous stirring. After cooling, honey was added to preserve its bioactive constituents.

2.4 Formulation of Polyherbal Syrup

The measured herbal extracts were gradually incorporated into the syrup base under continuous stirring. Lemon oil was added at the final stage. The resulting formulation was filtered and packed in amber-colored bottles.

3. Evaluation Parameters

3.1 Organoleptic Evaluation

The formulation was evaluated for:

• Color
• Appearance
• Odor
• Taste
• Homogeneity

3.2 Physicochemical Evaluation

The following parameters were determined:

• pH
• Viscosity
• Specific gravity
• Total solid content
• Stability

3.3 Preliminary Phytochemical Screening

Qualitative tests were performed for the detection of various phytochemical constituents.

Table 2. Phytochemical Screening

3.4 Determination of Specific Gravity

Specific gravity was measured using a pycnometer.

Table 3. Specific Gravity

3.5 Total Solid Content

Table 4. Total Solid Content

3.6 Microbial Load Analysis

Microbial testing was conducted according to WHO recommendations.

Table 5. Microbial Evaluation

3.7 Antioxidant Activity (DPPH Assay)

Table 6. DPPH Radical Scavenging Activity

Table 7. IC50 Values

3.8 Antimicrobial Activity

The antimicrobial activity was evaluated by agar well diffusion method.

Table 8. Zone of Inhibition

3.9 Heavy Metal Analysis

Table 9. Heavy Metal Content

3.10 Accelerated Stability Studies

Storage conditions:

• Temperature: 40 ± 2°C
• Relative Humidity: 75 ± 5%
• Duration: 3 Months

Table 10. Stability Study

RESULTS

Table 11. Physicochemical Evaluation of Herbal Syrup