Antimycobacterial activity of two Berberis species used as traditional medicine in Iran

Abstract number: P579

Khadem F., Zare Maivan H., Movassagh H., Salimi M., Sharifi M., Sohrabi T., Yazdanpanah B., Rostami Baroei M., Abolhassani M.

Objectives: Tuberculosis (TB) is the leading cause of mortality worldwide, infecting about 9 million people and killing approximately 2 million people annually. In recent years, emerging multiple drug resistance (MDR) has become a major threat, thus there is an urgent need to search natural products for developing new, effective and affordable anti-TB drugs. Berberidaceae, especially berberis species are well known medicinal plants and are used in traditional medicine, foods and dies in Iran. Chemical composition of Berberidaceae species show that their anti-inflammatory and anti-tuberculosis activity is mainly due to alkaloid constituents. This study was conducted to compare antimycobacterial activity of extracted alkaloids from root bark and fruit of Berberis vulgaris and B. integgerima from the natural flora of Khorasan ecological region.

Methods: Root bark and fruit from two species were collected, shade air dried, lyophilised and powdered. Chloroform extracts containing alkaloid fractions were obtained. Fresh solutions of each extract were dissolved in 2% DMSO. The Chloroform extracts were incorporated into the Lowenstein-Johnson medium after solidification with final concentrations of 500, 250, 125, 62.5 and 31 mg/ml. Bacterial suspension test was adjusted to 3×10⁵ CFU per ml Mycobacterium bovis BCG (Strain 1173 P2, Institut Pasteur, Paris, France) and incubated in 37 degrees of Celsius for 21 days. The minimum inhibitory concentration (MIC) amounts were evaluated after 21, 28 and 35 days of incubation. Mycobacterium bovis BCG was cultured in presence and absence of reference drug (Kanamycin) as controls. All tests were carried out five times.

Results: All four root bark and fruit chloroform extracts showed significant (P < 0.05) MIC concentrations (31–500 mg/ml), therefore 31 mg/ml was considered to be the best MIC for all four extracts.

Conclusion: Medicinal plants are an important resource to find original active drugs or new therapeutic agents especially against TB. The results indicate that root bark and fruit of Berberis vulgaris and B. integgerima can be used as antimycobacterial agents because of their considerable MIC values. Our investigations show that these remarkable results are due to alkaloids such as berberine, palmatine, oxyacantine and jatrorrhizine. Further investigations are required to assess the activities of these compounds against MDR M. tuberculosis.