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Journal of Drug Delivery and Therapeutics

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Antimicrobial Activity of Andrographis alata (Vahl) Nees

Yasothkumar N^1*, Sankaralingam S²

¹ Department of Botany, Yadava College, Tiruppalai, Madurai – 625014, Tamil Nadu, India

² Post Graduate and Research Department of Botany, Saraswathi Narayanan College, Perungudi, Madurai – 625002, Tamil Nadu, India

1. INTRODUCTION

Microorganisms gain resistance to the existing drugs and cause undesirable side effects. Antimicrobial properties have been reported in a wide variety of plant extracts with goal to discover new chemical classes of antibiotics that could resolve these problems ¹. The plant derived compounds show broad-spectrum of biological activity against infection causing agents such as bacteria, fungi, protocists, protozoans, viruses and yeast ^2,3. The potential for developing antibiotics from higher plants appears rewarding, as it will lead to the development of phytomedicine. In this concern, the present study was aimed to evaluate the antimicrobial potential of entire plant extract of Andrographis alata.

2. MATERIALS AND METHODS

2.1. Preparation of extracts

Fresh plant samples of Andrographis alata (Vahl) Nees (Family: Acanthaceae; Local name: Periyaanangai) were collected from Karandamalai located in Dindigul district of Tamil Nadu, India. It is lies between 19.2849º N latitude and 78.2169º E longitude. The collected specimens were botanically confirmed and authenticated as per the data pertained in The Plant List ⁴. 25 gram of air-dried plant parts was powdered and extracted with 250 ml of hexane, ethyl acetate and methanol separately. The extracts were then filtered and used directly for antimicrobial activity.

2.2. Procurement of microbial strains

Six pathogens such as Bacillus cereus, Staphylococcus epidermidis, Escherichia coli, Salmonella paratyphi, Beauveria bassiana and Candida albicans were obtained from Bose X-ray and Clinical Laboratory, Madurai, Tamil Nadu. Stock cultures were maintained at 4°C on slopes of nutrient agar. Active cultures for experiments were prepared by transferring a loopful of cells from the stock cultures to test tubes and were incubated without agitation for 24 hrs at 37°C.

2.3. Preparation of media (gram/litre)

Beef infusion                             : 300

Casein hydrolysate                 : 17.5

Starch                                          : 1.5

Agar                                             : 17

These ingredients were dissolved in 1000 ml distilled water; the pH was adjusted to 7.4 and sterilized at 121^o C for 75 minutes.

2.4. Determination of antimicrobial activity

The microbial activity of the crude extract was determined in accordance with the agar well diffusion method ⁵. 100 µl of cell suspension was spread on each petridish containing agar medium. Wells were bored onto the agar using a sterile 6 mm diameter cork borer. 20mg/ml of the crude extract was added into the wells and incubated at 37^o C for 24 hrs. The plates were observed for zone of inhibition after 24 hrs. These effects were compared with streptomycin at a concentration of 10µg/ml.

3. RESULTS AND DISCUSSION

For the present study the antimicrobial activity of Andrographis alata extracts were tested against bacterial and fungal strains. The results showed that the methanol extract had an effective antimicrobial activity against all the tested microorganisms. The methanol extract produced the inhibition zone of 15±0.8 mm against Beauveria bassiana 14±0.4 mm against Escherichia coli, Candida albicans, 13±0.3 mm against Salmonella paratyphi, 11±0.3 mm against Staphylococcus epidermidis and 10±0.4 mm against Bacillus cereus. Meanwhile, the hexane extract had low antimicrobial activity against all the tested microorganisms (Table 1; Fig 1).

Table 1: Antimicrobial potential of A. alata

Figure 1: Comparative antimicrobial activity of A. alata against different pathogens

The present study revealed that the methanolic extracts demonstrated the highest antimicrobial activity when compared to the other solvents (hexane and the ethyl acetate). This may be due to the better solubility of the active components in methanolic solvent ⁶. These results coincide with the previous works ^7-11 and some of these observations have helped in identifying the active principle responsible for such activities and in the developing drugs for the therapeutic use in human beings.

4. CONCLUSION

Further research is needed for the evaluation of other biological active potentials like antioxidant, antidiabetic, anti-inflammatory activities of Andrographis alata in vitro. For this, large scale isolation and spectral techniques are required to isolate and identify a particular compound responsible for respective pharmacological action. The in vivo studies should also be carried out to describe the mechanism of action of these compounds in living systems using animal models.

CONFLICT OF INTEREST

The author has declared that there is no conflict of interest.

REFERENCES

1. Piddock KJV & Wise R. Mechanism of resistance to quinolones and clinical perspective. Journal of Antimicrobial Chemotherapy, 1989; 23:475-­483.
2. Boyd RF. Basic Medical Microbiology (5^th Edition). Little, Brown and Company, Boston, 1995; 310-314.
3. Cookson BD. Methicillin-resistant Staphylococcus aureus in the community: New battlefronts, or are the battles lost? Control of Hospital Epidemiology, 2000; 21:398-403.
4. The Plant List. 2021. The Plant List: A working list of plant species, version 1. http://theplantlist.org/. Accessed on 17^th April, 2021.
5. Irobi ON, Moo-youg M, Anderson WA & Daramola SO. Antibacterial activity of bark extracts of Bridelia ferruginea. Journal of Ethnopharmacology, 1994; 43:223-224.
6. De Boer HJ, Kool A, Broberg A, Mziray WR, Hedberg I & Levenfors JJ. Antifungal and antibacterial activity of some herbal remedies from Tanzania. Journal of Ethnopharmacology, 2005; 96:461-469.
7. Poornima N, Umarajan KM & Babu K. Studies on anatomical and phytochemical analysis of Oxystelma esculentum (L.f.) R.Br. ex. Schultes. Botany Research International, 2009; 2(4):239-243.
8. Ismail Shareef M & Leelavathi S. Evaluation of antioxidant activity of Anisolmeles malabarica R.Br. and Clerodendrum serratum L. extracts against rheumatism. Research Journal of Pharmaceutical, Biological and Chemical Sciences, 2011; 2(4):488-495.
9. Annie Felicia F & Muthulingam M. Phytochemical and HPTLC studies of methanolic extract of Indigofera tinctoria (Fabaceae). International Journal of Pharmacy and Life Sciences, 2012; 3(5):1670-1674.
10. Ilango K, Maharajan G & Narasimhan S. Preliminary phytochemical screening and antibacterial activity of fruit pulp of Momordica dioica Roxb. (Cucurbitaceae). African Journal of Basic & Applied Sciences, 2012; 4(1):12-15.
11. Usha M, Appavoo MR & Immanuel G. Pharmacognostical study and preliminary phytochemical screening of the leaf of Ixora johnsonii Hook.f. - A rare, endemic, critically endangered species of southern Western Ghats of Kerala, India. International Journal of Pharmaceutical and Phytopharmacological Research, 2012; 5:263-270.