Healing peel

Pomegranate fruit is traditionally known for its remedial action in cases of acidosis, dysentery, microbial infections and diarrhoea.-M. SRINATH

THE pericarp of pomegranate (Punica granatum) could help combat multi-drug resistant (MDR) microbial infections. Scientists from Jadavpur University, West Bengal, and a Kolkata-based private clinical testing centre have reported in the latest issue of Food and Chemical Toxicology that superbugs such as Psedomonas aeruginosa produce extended-spectrum beta-lactamase (ESBL) and metallo beta-lactamase (MBL) which enable the bacilli to be resistant to antibiotics such as ciprofloxacin.

It is believed that plant-based natural products, which have been known to help fight bacterial infections, may play a supplementary role in combating MDR bacteria with antibiotics. For example, oregano essential oil, given in combination with fluoroquinolones, was found to enhance the activity of the drugs against ESBL-producing E. coli. Similarly, various researchers have reported the enhancement of anti-microbial activity of drugs when given in combination with plant-derived terpenoids and flavonoids. Pomegranate fruit is traditionally known for its remedial action on acidosis, dysentery, microbial infections, diarrhoea, helminthiasis, haemorrhage and even respiratory pathologies. Dried pomegranate peel has been traditionally recommended for treatment of various disorders such as colitis, headache, aphthae, diarrhoea, dysentery and ulcers. The medicinal benefits of pomegranate have been attributed to the antioxidant effect of its phyto-chemicals, which include hydrolysable ellagitanins, anthocyanins and other polyphenols.

In their study, the scientists made a comparative assessment of edible and non-edible parts of the fruit, in particular the pericarp, known for its high polyphenol content. This was tested in combination with ciprofloxacin for its antimicrobial effect against ESBL-producing E. coli and K. pneumoniae and MBL-producing P. aeruginosa for the first time. They found that 19 out of 49 strains exhibited a greater synergetic action of ciprofloxacin and methanoloic extract of pomegranate pericarp compared with pomegranate juice. The scientists believe that the high content of polyphenolics and flavonoids in the extract probably plays a crucial role in inhibiting the efflux of MDR proteins from these bacteria.