Evaluation of the effect of Pulicaria gnaphalodes and Perovskia abrotanoides essential oil extracts against Mycobacterium tuberculosis strains

A review of medicinal plant of Middle East and North Africa (MENA) region as source in tuberculosis drug discovery

Tuberculosis (TB) is a disease that affects one-third of the world's population. Although currently available TB drugs have many side effects, such as nausea, headache and gastrointestinal discomfort, no new anti-TB drugs have been produced in the past 30 years. Therefore, the discovery of a new anti-TB agent with minimal or no side effects is urgently needed. Many previous works have reported the effects of medicinal plants against Mycobacterium tuberculosis (MTB). However, none have focused on medicinal plants from the Middle Eastern and North African (MENA) region. This review highlights the effects of medicinal plants from the MENA region on TB. Medicinal plants from the MENA region have been successfully used as traditional medicine and first aid against TB related problems. A total of 184 plants species representing 73 families were studied. Amongst these species, 93 species contained more active compounds with strong anti-MTB activity (crude extracts and/or bioactive compounds with activities of 0-100 µg/ml). The extract of Inula helenium, Khaya senegalensis, Premna odorata and Rosmarinus officinalis presented the strongest anti-MTB activity. In addition, Boswellia papyrifera (Del) Hochst olibanum, Eucalyptus camaldulensis Dehnh leaves (river red gum), Nigella sativa (black cumin) seeds and genus Cymbopogon exhibited anti-TB activity. The most potent bioactive compounds included alantolactone, octyl acetate, 1,8-cineole, thymoquinone, piperitone, α- verbenol, citral b and α-pinene. These compounds affect the permeability of microbial plasma membranes, thus kill the mycobacterium spp. As a conclusion, plant species collected from the MENA region are potential sources of novel drugs against TB.

Antimicrobial and Antihypercholesterolemic Activities of Pulicaria gnaphalodes

Multidrug resistance has increased globally in the communities. Bacterial infections associated with health care have weakened the existing antimicrobial therapy and demand the search for alternative therapies. In the present investigation, the medicinal plant Pulicaria gnaphalodes from Quetta, Pakistan, has been screened for antimicrobial potential. In vitro antimicrobial efficacy of P gnaphalodes extracts (methanol and ethanol) was quantitatively evaluated on the basis of zone of inhibition against different bacteria and minimum inhibitory concentration (MIC). In vivo, antihypercholesterolemic activity is determined in different rat groups. The results of the study indicated that the ethanol extract of P gnaphalodes showed maximum zone of inhibition for Bacillus subtilis of 12.1 ± 1.1 mm from all others. The methanol extract showed maximum zone of inhibition for Staphylococcus aureus of 11.9 ± 1.0 mm and rifampicin showed maximum zone of inhibition of 23.1 ± 0.9 mm. The results of ethanol and methanol extract of P gnaphalodes against different bacteria revealed that this plant has greater antimicrobial activity. However, the plant extract shows nonsignificant antihypercholesterolemic activity. The extract of this plant can be utilized as medicine to inhibit several infections caused by some bacterial pathogens found in human body.