B. Duraiswamy*, Sagar kumar Mishra, V. Subhashini, S. A. Dhanraj and B. Suresh

Department of Pharmacognosy, J. S. S. College of Pharmacy, Rocklands, (P.B. No. 20), Ootacamund-643 001, India.

*Corresponding Author:
B. Duraiswamy
Department of Pharmacognosy, J. S. S. College of Pharmacy, Rocklands, (P.B. No. 20), Ootacamund-643 001, India.
E-mail: bdurais@yahoo.com
Date of Submission 10 March 2005
Date of Revision 02 August 2005
Date of Acceptance 12 June 2006

Indian J Pharm Sci, 2006, 68 (3): 389-391		  

DOI: 10.4103/0250-474X.26671

Abstract

The methanol extracts of Mahonia leschenaultii takeda (Berberidaceae) root and root bark were tested for antibacterial potential against Escherichia coli (NCIM 2068), Pseudomonas aeruginosa (NCIM 2053), Staphylococcus aureus (NCIM 2492), and Staphylococcus epidermitis (NCIM 2493) on nutrient agar medium and nutrient broth using ampicillin trihydrate as standard drug. For antifungal study, stains used were Trichophytons lignorum (NCIM 1195) and Candida crusei (NCIM 3129) on Sabourauds dextrose agar (SDA) and Sabourauds dextrose broth (SDB) by cup plate method using amphotericin B as standard drug. The results showed that all extracts exhibited significant activity against all the selected strains of bacteria and relatively more against Staphylococcus epidermitis . The antifugal activity was less significant when compared with antibacterial activity.

Introduction

Mahonia leschenaultii takeda species of Berberidaceae family is a shrub with rough, greyish-brown, corky bark. Leaves in circles present at the ends of the slender branches. Flowers are yellow, in long erect racemes [1,2]. The root of this plant is rich in alkaloids; the principal alkaloids are berberine (1.02%), neprotine (0.011%), oxyacanthine (trace), palmatine (0.075%), and jatrorrhizine (0.031%) [3]. It is locally called Thovari, and medicinally the paste of the stem bark is used by the Todas, the Nilgiri tribe, in postnatal treatment in women [4]. The LD50 value of the 50% ethanol extract of the aerial parts of this plant was found to be 280 mg/kg on mice, found to have effect on respiration and possessed diuretic activity [5]. The present study is taken up to screen antibacterial and antifungal potential of the methanol extract of the root and root bark of Mahonia leschenaultii takeda.

The plant Mahonia leschenaultii takeda, present in the outskirts of forests, at high elevations, was collected from Pykara forest area, Udhagamandalam, Nilgiri District of Tamil Nadu, in the month of June. It was identified by the Botanical Survey of India, Coimbatore, and a voucher specimen was deposited in the Department of Pharmacognosy for future reference. The underground

root part was separated from the aerial parts and the root bark was then peeled from the root. Both root and root bark were air/shade dried and mechanically powdered separately to obtain a course powder, which was then subjected to extraction in a Soxhlet apparatus using methanol. Solvent extraction under reduced pressure afforded 8.63 and 8.40% extracts from root bark and root, respectively. The extracts were then subjected to antibacterial and antifungal testing. All bacterial and fungal strains were obtained from National Chemical Laboratory, Pune.

The root and root bark extracts were screened for antifungal and antibacterial activity by cup plate method using amphotericin B in dimethyl sulphoxide (DMSO, 1 mg/ml) and ampicillin trihydrate in DMSO (1 mg/ml) as standard drugs, respectively. The extracts were prepared by dissolving each of 200 mg of root and root bark extract in 10 ml of DMSO (20 mg/ml).

The antimicrobial activity [6-8] was evaluated by the agar diffusion method employing 24-hour culture of six different test organisms, viz., E. coli (NCIM 2068), Ps. aeruginosa (NCIM 2053), St. aureus (NCIM 2492), St.epidermitis (NCIM 2493), T. lignorum (NCIM 1195), and C. crusei (NCIM 3129). The bacterial and fungal stains (1 ml each) were initially inoculated in 100 ml of sterile nutrient broth and incubated for 37°±1° for 24 h and 28°±1° for 48 h, respectively and were diluted with sterile water so as to get a test inoculum of 106?107 cfu/ml solution (working stock). The test organisms from the working stock were seeded into sterile nutrient agar medium/Sabouraud?s Dextrose Agar (SDA) medium by uniformly mixing 0.2 ml of the working stock with 100 ml of sterile nutrient agar cooled to 48° to 50° in a sterile Petridish. When the nutrient agar/SDA medium solidified, four holes of uniform diameter (5 mm) were made using sterile aluminium borer. The standard solution, the methanol extracts of root, root bark, and 20 mg/ml solution of isolated berberine (0.2 ml each) were placed in each hole separately under aseptic condition. The plates were then maintained at room temperature for 2 h to allow the diffusion of the solution into the medium. All the bacterial plates were then incubated at 37°±1° for 18 h and the zone of inhibition measured (for each zone an average of three independent determinations was noted). The extracts of root, root bark, and standard solution of berberine (0.2 ml each) were subjected to antifungal study by cup plate method using amphotericin B as standard drug (0.2 ml of 1 mg/ml) at 28° ±1° on SDA, and the zone of inhibition was compared.

In Nilgiris, the ethnic tribe Todas use the plant Mahonia leschenaultii takeda in postnatal treatment in women. Results of the preliminary antifungal and antibacterial screening of methanol extracts of the root and root bark (Tables 1 and 2) revealed significant activity against all strains ? the highest against S. epidermiti when compared with standard drug. The root bark extract showed more significant activity against the organisms than that of the extracts of the root. The highest activity was shown by root bark against S. epidermiti. The antifungal activity was relatively less as compared to antibacterial activity.

Extract tested Concentration mg/well   Diameter of zone of inhibition (cm)
    T. lignorum C. crusei
Methanol extract of root 4 2.95 2.25
Methanol extract of the root bark 4 3.00 2.30
Berberine 4 3.05 2.25
Amphotericin B 0.2 4.10 3.95

Table 1: Antifungal Activity Of The Root And Root Bark Of Mahonia Leschenaultii Takeda

Extracts tested Conc. mg/well   Diameter of the zone of inhibition in (cm)
    E. coli P. aueroginosa S. aureus S. epidermitis
Methanol extract of root 4 2.95 2.85 2.80 3.40
Methanol extract of root bark 4 3.05 3.05 3.15 4.10
Berberine 4 3.15 3.05 3.65 3.10
Ampicillin 0.2 4.10 4.05 4.25 3.95

Table 2: Antibacterial Activity Of The Root And Root Bark Of Mahonia Leschenaultii Takeda

Acknowledgements

The authors are grateful to Jagadguru Sri Sri Shivarathreeshwara Deshikendra Mahaswamigalavaru of Sri Sutter Matt, Mysore, for providing facilities for successful completion of this work.

References