Evaluation of Anti-depressant activity of Imperata cylindrica Roots Extract in swiss albino mice

Vastavi Gore* and Dr. Anant Kumar Patel

College of Pharmacy, Swami Vivekanand Group of Institutions, Indore (Madhya Pradesh), India.

*Correspondence: vastavigore17@gmail.com

DOI: https://doi.org/10.71431/IJRPAS.2025.4302  

INTRODUCTION

Imperata cylindrica (Cogon grass) is a rhizomatous grass [1]. It is known to be rich in phenols and triterpenes [2]. Recent studies in pharmacology reveal that I. cylindrica possesses various compounds exhibiting significant and varied biological properties such as hemostasis, improvement of urination, anti-inflammatory, antibacterial, anticancer, enhancement of the immune system, etc. [3]. Saponins, flavonoids, phenols, and glycosides are the main components of these substances [4]. Depression is a heterogeneous syndrome characterized by varying signs and symptoms including sad mood, irritable behaviour, insomnia, anorexia, suicidal tendency, etc. [5]. This study focuses on the phytochemical screening and pharmacological evaluation of saponins, tannins, flavonoids, carbohydrates, phenols, and cardiac glycosides isolated from Cogon grass to investigate their potential antidepressant effects.

MATERIALS AND METHODS

Plant Material

Fresh roots of Imperata cylindrica were collected from local market of Indore (Madhya Pradesh) and authenticated. The plant material was cleaned, washed with running water, dried in shade in clean and dust free environment. The roots were grounded to powder and stored in air tight container till further use [6].

Extraction Preparation

The root extract was carefully made using the cold maceration method over one week, which encompassed several steps: Powder Collection and Defatting, extracting the useful components with different solvents, then preparing the aqueous extract, and filtering and drying the solution at reduced temperatures [7].

Phytochemical Screening

Imperata cylindrica was subjected to various phytochemical tests for checking the presence of Alkaloids, Tannins, Reducing Sugars, Cardiac Glycosides, Flavonoids, Carbohydrates, and Proteins contributing for their therapeutic effects and various biological functions.

·         Dragendorff’s test (Test for Alkaloids): 6 mL of root extract was taken and evaporated. Dissolve the residue in 6mL of alcohol at 60˚. The resulting alcoholic solution was divided in two test tubes. In the 1^st test tube, 2 drops of Dragendorff’s reagent were taken. Formation of orange brown precipitation, indicates the presence of alkaloids. In the 2^nd test tube, 2 drops of Bouchardat’s reagent were added. The appearance of a reddish-brown coloration indicates the presence of alkaloids [8].

·         Wagner’s Test (Test for Alkaloids): Root Extract was mixed with 2ml of 1% HCl and heated gently. Mayer’s and Wagner’s reagents were added to mixture. Turbidity observed in precipitates serves the indicator for presence of alkaloids [9].

·         Ferric Chloride test (Test for Tannins): Root Extract was mixed with 2ml of 2% solution of FeCl₃. Dark blue or greenish grey coloration indicates the presence of tannins. [9].

·         Fehling’s solution (A and B) (Test for Reducing Sugar): Equal volume of Fehling A and Fehling B reagents were mixed and 2ml of it was added to Root Extract and boiled. Brick-red precipitate appearance at the bottom of the test tube indicates the presence of reducing sugars [9].

·         Keller-Kiliani test (Test for Cardiac Glycosides): Root extract was mixed with 2ml of Glacial Acetic Acid containing 1-2 drops of 2% solution of FeCl₃ solvent. The resulting mixture was transferred to another test tube with 2ml of concentrated H₂SO₄. Brown ring at the interphase indicates the presence of cardiac glycosides [9].

·         Alkaline Reagent Test (Test for Flavonoids): Root Extract was mixed with 2ml of 2% solution of NaOH. An intense yellow colour was formed which turned colorless on addition of few drops of diluted acid, indicates the presence of flavonoids [9].

·         Lead Acetate test (Test for Flavonoids): Few drops of lead acetate were added to 1 mL of root extract. A large white-brown precipitate formation indicates positive test for tannins [10].

·         Molisch’s test (Test for Carbohydrates): Root Extract was mixed with 2ml of Molisch’s reagent and shaken accurately, 2ml of concentrated H₂SO₄ was poured carefully along the side of the test tube. Appearance of a violet ring at the interphase indicates the presence of carbohydrate [9].

·         Benedict’s test (Test for Carbohydrates): Root Extract mixed with 2ml of Benedict’s reagent and boiled, a reddish-brown precipitate formation indicates the presence of the carbohydrates [9].

·         Millon’s test (Test for Proteins): Root Extract mixed with 2ml of Millon’s reagent, white precipitate appearance turning red upon gentle heating confirms the presence of protein [9].

Acute Toxicity Study

Toxicity studies of root extract were carried out in swiss albino mice weighing 25-30gm. They were performed according to OECD (Organization for Economic Cooperation and Development) guidelines (423). The sighting study aims to determine the appropriate starting dose by selecting from fixed dose levels of 50, 300, and 2000 mg/kg, with the goal of identifying a dose that is expected to produce evident toxicity, mortality, and behavioral changes over a 14-day period [11].

Pharmacological Evaluation

The Antidepressant effects were evaluated by measuring total immobility time and behavioural changes in depressed swiss albino mices. The swiss albino mices were divided into different groups:

1.      Control Group

2.       Standard Drug (Fluoxetine)

3.      Low dose of extract

4.      Intermediate dose of extract

5.      High dose of extract

RESULTS

Phytochemical Screening

The root extract of Imperata cylindrica was subjected for phytochemical screening and found that alkaloids, reducing sugars, cardiac glycosides, flavonoids, carbohydrates, and proteins were present. The results were shown below in Table 1.

Table 1. Phytochemical Screening for Phytoconstituents

Acute Toxicity Study

The results from the acute toxicity study are summarized below:

Table 2. Acute Toxicity evaluation

Figure 1: Acute Toxicity Bar Graph

Pharmacological Evaluation

The pharmacological assessment indicated an improvement in the mood of mice, which was demonstrated by a following reduction in the duration of their immobility time by two different animal models of depression i.e., Forced Swim Test and Tail Suspension Test:

1.      Forced Swim Test:

The Forced Swim Test was conducted as described by 25 with slight modifications. The mice were forced to swim individually in an open cylindrical container (diameter 14 cm, height 20 cm) filled with water up to a depth of 15 cm, and temperature maintained at 25 ± 1°C. The immobility was shown by mice when they were exposed to unavoidable and inescapable stress conditions reflected behavioral despair signifying depressive disorder similar in humans. The duration of immobility was measured at the end of the procedure for 4 min in the total 6 min protocol [5].

The changes in the immobility duration were studied after 30 minutes of administration of the Imperata cylindrica roots extract (250, 500, 1000mg/kg) in the test group, Fluoxetine (25mg/kg) in the standard group and Distilled Water (1ml/kg) in the control group.

Table 3. Pharmacological evaluation by Forced Swim Test

Figure 2: Forced Swim Test results bar graph

2.      Tail Suspension Test

Mice were hung on a wooden rod, 50 cm above the table, by attaching them from their tail end with the use of an adhesive tape. The first two minutes were not recorded, and the periods of immobility for the latter six minutes were recorded (in seconds) with a stopwatch. Mice were considered to be immobile only when they were motionless and not attempting to escape [12].

The changes in the immobility duration were studied after 30 minutes of administration of the Imperata cylindrica roots extract (250, 500, 1000mg/kg) in the test group, Fluoxetine (25mg/kg) in the standard group and Distilled Water (1ml/kg) in the control group.

Table 4. Pharmacological evaluation by Tail Suspension Test

Figure 3: Tail Suspension Test results bar graph

DISCUSSION

Phytochemical Screening

The positive results from the Dragendorff’s test, Wagner’s Test, Fehling’s test, Keller-Kiliani test, Alkaline reagent test, Lead Acetate test, Benedict’s test and Million’s test confirm the presence of alkaloids, reducing sugars, cardiac glycosides, flavonoids, carbohydrates, and proteins in Imperata cylindrica. These phytoconstituents are known to exhibit various biological activities, including antidepressant effects, which are central to this study.

Acute Toxicity

In Acute Oral Toxicity study, the root extract of Imperata cylindrica demonstrated no lethal effect and was found to be relatively safe at doses up to 2000 mg/kg, administered orally (p.o) and test doses of 250mg/kg, 500mg/kg and 1000mg/kg, p.o were used for pharmacological activity indicating that the extract of Imperata cylindrica had no significant mortality or behavioral changes were observed in any of the treatment groups, supporting the safety of roots extract isolated for potential therapeutic use.

Pharmacological Effects on the Immobility time

The administration of I. cylindrica root extract significantly lowered the immobility time in mices, particularly at the higher dose (1000 mg/kg). These effects are comparable to those seen with the standard antidepressant drug, Fluoxetine, suggesting that I. cylindrica possess potential as a natural alternative for managing depression.

CONCLUSION

Alkaloids, Reducing Sugars, Flavonoids, Carbohydrates, and Proteins isolated from I. cylindrica exhibit promising antidepressant activity by improving immobility time in depressed mices. The pharmacological study confirms their safety, even at higher doses. Further studies are needed to explore the molecular mechanisms underlying their effects and to optimize their use in clinical settings.

CONFLICT OF INTEREST

The authors assert that there are no conflicts of interest.

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