Image caption Cockroach brains contain powerful antimicrobial compounds which can kill MRSA

Cockroaches, far from being a health hazard, could be a rich source of antibiotics.

A study of locust and cockroach brains has found a number of chemicals which can kill bugs like MRSA.

Scientists hope these could become a powerful new weapon to boost the dwindling arsenal of antibiotics used to treat severe bacterial infections.

The research was announced at a meeting of the Society for General Microbiology.

The researchers discovered nine different chemicals in the brains of locusts and cockroaches, which all had anti microbrial properties strong enough to kill 90% of MRSA (Methicillin-resistant Staphylococcus aureus) while not harming human cells.

Cockroaches have a reputation for tenacity and for thriving in dirty environments.

Simon Lee from Nottingham University is the author of the study. He said that it is this capacity to live in dirty, infectious conditions that mean insect brains contain these kinds of compounds.

"They must have some sort of defense against micro organisms. We think their nervous system needs to be continuously protected because if the nervous system goes down the insect dies. But they can suffer damage to their peripheral structures without dying," he told BB News.

He hopes the compounds could go on to be used to treat multi drug resistant infections like E. Coli and MRSA which are becoming increasingly difficult to treat using some of the most powerful antibiotics available to medicine.

"A kill rate of 90% is very very high, and I diluted the substance down so there was only a minute amount there. Conventional antbiotics reduce the number of the bacteria and let your immune system cope with the rest. So to get something with such a high kill rate that is so potent at such a low dose is very promising," he told BBC News.

The compound would need years of testing for safety and efficacy before any drugs developed from them could go on the market.