Feijoa and blackberry are two fruits with a strong anti-inflammatory effect that could help people with inflammatory diseases, according to recent research from the University of Auckland.
The research into treatments for inflammatory bowel disease investigated the anti-inflammatory and anti-oxidant properties of 12 fruits.
They tested mango, feijoa, elderberry, cranberry, blackcurrant, blackberry, red raspberry, strawberry, green grapes, plum, pear and black grapes.
"Most fruits are good for you and have some anti-oxidant effect, but feijoa and blackberry showed the strongest anti-inflammatory response in the experiments," says University of Auckland, Nutrition and Dietetics researcher, Professor Lynn Ferguson.
The study identified fruit compounds with an anti-inflammatory effect through certain chemical pathways that could be tested further to develop them as complementary therapies for inflammatory bowel disease and other inflammatory disorders.
"Inflammatory responses are important for coping with damage, but an over-active inflammatory response is also damaging and can create problems, says Professor Ferguson. "These responses can be debilitating for New Zealanders with an inflammatory disease, and these fruits can help to limit the inflammatory response."
Feijoa and blackberry showed the highest and strongest anti-inflammatory effects in the various test screens carried out for this research. The study also showed that the anti-oxidant action of the feijoa compounds was not a direct effect, but was mediated through inhibitory effects on the enzyme, kinase.
"Our studies support other results that suggest these fruit extracts could help to regulate oxidative stress and inflammation in cells, both directly and indirectly," says Professor Ferguson.
"Feijoa is already known to be very high in polyphenols such as flavonoids and these may be responsible for the anti-inflammatory effects. Research to identify the active compounds will be the subject of further studies," she says.
For the experiments reported in the study, the testing included the skin and pulp of all the fruits.
"In feijoa, the skin has more bio-activity than the pulp," says Professor Ferguson. "Some Asian cultures eat the skin, but in most western cultures many people find the taste too sour."
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