Feathered friends favor fruity flavonoids

Researchers from the University of Freiburg and the Max Plank Institute for Ornithology in Germany offered a group of blackcaps a choice of two foods. The foods were identical in all respects except for the amount of flavonoids they contained, and the researchers found that the blackcaps actively selected the food with added flavonoids.

As well as the food selection experiment, the study also looked at whether or not the flavonoids had an impact on the birds’ health. They found that, compared with birds not fed the antioxidants, blackcaps that ate modest amounts of flavonoids for four weeks had stronger immune systems.

According to the lead author of the study, Carlo Catoni of the University of Freiburg: “We fed the birds an amount of flavonoids that they would obtain by eating 1-2 blackberries, bilberries or elderberries a day. We used this modest intake of flavonoids because high quantities are only available during the limited time of maximum berry abundance. Our study shows for the first time that flavonoids are beneficial compounds that can boost the immune system in a living organism. We also found that wild birds actively select food containing flavonoids. Our results have important implications for the study of ecology and immunity in birds, and for the evolution of the relationship between plants and the birds and animals they rely on to disperse their seeds.”

In this study, the birds were able to tell which food had added flavonoids because – as would be the case in nature – flavonoids made the food a darker colour. However, the authors believe that the blackcaps know that the darker berries contain more flavonoids, and this is why they prefer them. “Studies by other ecologists and our own group have shown that blackcaps do not show a colour preference if food is nutritionally identical, so we are confident that our results are due to a learned selection for flavonoid content and not due to innate selection of darker food per se,” Catoni says.

Flavonoids – found in very high concentrations in fruits and vegetables – are among the commonest antioxidants in nature. Health benefits of dietary antioxidants have been the focus of much research during the past decade: during the past few years, more than 30,000 studies have been published on the health effects of flavonoid consumption, but only a handful of these involved living organisms. Although the mechanisms are not fully understood, scientists think that antioxidants help protect cells from damage by free radicals.

The blackcap (Sylvia atricapilla) is a European migratory species and eats fruit and insects. Because of its delightful fluting song, the blackcap has been dubbed the 'northern nightingale'. Primarily a summer visitor to the UK, birds from Germany and north-east Europe are increasingly spending the winter in the UK.

Source: Wiley

Natural plant materials to regulate starch digestion
Researchers in Switzerland are reporting discovery of natural plant materials that may regulate starch digestion — slowing down the body's conversion of potatoes, rice, and other carbohydrate-rich foods into sugar. The findings could lead to new functional foods that fight diabetes, they say in a report scheduled for the June 26 issue of the ACS' bi-weekly Journal of Medicinal Chemistry.
Miracle leaves that may help protect against liver damage
Sea buckthorn (Hippophae rhamnoides) berries are well known for their cholesterol busting properties, but scientists in India say that its leaves are also rich in anti-oxidants and may help ward off liver disease, according to new research due to be published in the Society of Chemical Industry’s (SCI) Journal of the Science of Food and Agriculture.
Plant flavonoid found to reduce inflammatory response in the brain
Researchers at the University of Illinois report this week that a plant compound found in abundance in celery and green peppers can disrupt a key component of the inflammatory response in the brain. The findings have implications for research on aging and diseases such as Alzheimer’s and multiple sclerosis.
Study in mice suggests molecules in plants have beneficial effect on Alzheimer's disease
A set of molecules found in certain plants appears to have a beneficial effect in brain tissue associated with Alzheimer’s disease, according to a new study conducted in mice. The study was led by researchers at the University of South Florida and Cedars-Sinai Medical Center. An article in the Journal of Cellular and Molecular Medicine is available online.
Getting forgetful? Then blueberries may hold the key
If you are getting forgetful as you get older, then a research team from the University of Reading and the Peninsula Medical School in the South West of England may have good news for you.
New insights into how natural antioxidants fight fat
Scientists in Taiwan are reporting new insights into why diets rich in fruits and vegetables reduce the risk of obesity. Their study, scheduled for the Oct. 17 (current) issue of ACS’ Journal of Agricultural and Food Chemistry, a bi-weekly publication, focuses on healthful natural antioxidant compounds called flavonoids and phenolic acids.
Researchers genetically engineer micro-organisms into tiny factories
Microorganisms may soon be efficiently and inexpensively producing novel pharmaceutical compounds, such as flavonoids, that fight aging, cancer or obesity, as well as high-value chemicals, as the result of research being conducted by University at Buffalo researchers.
Flavonoids in orange juice make it a healthy drink, despite the sugar
Orange juice, despite its high caloric load of sugars, appears to be a healthy food for diabetics due to its mother lode of flavonoids, a study by endocrinologists at the University at Buffalo has shown. The study appeared in the June 2007 issue of Diabetes Care.

Feathered friends favor fruity flavonoids

Related stories:

News discussion: