- Persian shallots used in traditional Iranian cuisine has antibacterial properties.
- The antibacterial properties were found to increase the effects of existing antibiotic treatment.
- All four compounds which were synthesized from the shallots prevented the growth of multidrug-resistant tuberculosis bacteria by more than 99.9 %.
The antibacterial properties extracted from the Persian shallot could increase the effects of existing antibiotic treatment.
The study led by Sanjib Bhakta of University College London (UCL) in the UK investigated extracts of bulbs from Allium Stipitatum - also known as the Persian shallot and used as a staple part of Iranian cooking - and its antibacterial effects.
‘Sulphur compounds from the Persian shallots inhibit the growth of Mycobacterium tuberculosis, Escherichia coli and multi-drug-resistant Staphylococcus aureus.’
The research team synthesized the chemical compounds present in these plants in order to better understand and optimise their antibacterial potential. They tested four different synthesised compounds, all of which showed a significant reduction in the presence of the bacteria in the multidrug-resistant tuberculosis.
The team concluded that the chemical compounds may work as templates for the discovery of new drug treatment to combat strains of tuberculosis, which have previously developed resistance to anti-bacterial drugs.
When a patient has a bacterial infection, they may be prescribed an antibiotic. In the case of TB, they will likely be prescribed a cocktail of four antibiotics including Isoniazid and Rifampicin - but increasingly, the pathogens in bacterial infections are developing resistance to antibiotic drugs.
Dr Sanjib Bhakta, one of the study's authors, from Birkbeck's department of biological sciences, said: "Despite a concerted global effort to prevent the spread of tuberculosis, approximately 10 million new cases and two million deaths were reported in 2016. In searching for new anti-bacterials, we tend to focus on molecules that are potent enough to be developed commercially as new drug entities by themselves."
"However, in this study we show that by inhibiting the key intrinsic resistance properties of the TB, one could increase the effects of existing antibiotic treatment and reverse the tide of already existing drug resistance," he added.
Prof Simon Gibbons, another author, and head of UCL's department of pharmaceutical and biological chemistry, said: "Natural products from plants and microbes have enormous potential as a source of new antibiotics. Nature is an amazingly creative chemist and it is likely that plants such as the Persian shallot produce these chemicals as a defense against microbes in their environment."
Scientists said they hope the molecules, which were tested in a laboratory, could be combined with existing antibiotics to form new anti-TB drugs.
- Cynthia A. Danquah, Eleftheria Kakagianni, Proma Khondkar, Arundhati Maitra, Mukhlesur Rahman, Dimitrios Evangelopoulos, Timothy D. McHugh, Paul Stapleton, John Malkinson, Sanjib Bhakta, Simon Gibbons. 'Analogues of Disulfides from Allium stipitatum Demonstrate Potent Anti-tubercular Activities through Drug Efflux Pump and Biofilm Inhibition.' Scientific Reports (2018). doi:10.1038/s41598-017-18948-w.