by India Glyde, University of Wollongong

Credit: Pixabay/CC0 Public Domain

New research reveals Queen Garnet plums, elderberries and more have antioxidants that could protect your brain from illness.

Led by Naomi May, a Ph.D. candidate in the School of Medical, Indigenous and Health Sciences, the research found that different species of plant compounds were associated with various antioxidant effects, such as the ability to prevent oxidative stress-induced cell death in neuron-like cells, scavenge reactive oxygen and nitrogen species, and chelate metal ions. These contribute to neuronal damage and the progression of brain illnesses.

While the benefits of plant-based diets are well known, the study, published in Food & Function, sought to uncover which compounds were responsible for the positive effects on the brain.

The paper was co-authored by Dr. Jiahua Shi, Helen Clunas, Dr. Julianna Lys de Sousa Alves Neri, Dr. Celine Kelso, Dr. Jody Morgan, Dr. Yinghua Yu, Professor Karen Charlton, and Associate Professor Katrina Weston-Green from UOW.

The researchers were interested in the health benefits of various classes of plant compounds: phenolics, which can contribute to the plants' color, and terpenes, which are responsible for the flavor and fragrance of plants. May used mass spectrometry to measure the individual species of the plant compounds in order to determine which species are associated with various antioxidant and neuroprotective effects.

"Many plant-based foods have been shown to benefit our brain and overall health," May said. But until now, we haven't known which complex mix of compounds packs the most punch.

"Why is lemon balm calming? How can sage help the body? Why are elderberries so beneficial to our immune system? We finally have data to begin to answer these questions."

The research focused on six specific plant-based foods—Queen Garnet plum, black pepper, clove, elderberry, sage and lemon balm—and found they have antioxidant and protective effects on the brain. It also looked at over-the-counter complementary food supplements derived from these plants, including two blends rich in astragalus and lemon balm.

The astragalus supplement had the highest rates of phenolics, followed by the Queen Garnet plum, elderberry, and clove. In particular, these plant products were high in derivates of a compound called quercetin, which was associated with an ability to prevent oxidative stress-induced cell death and chelate copper ions. Black pepper had the strongest terpene concentration, followed by clove and sage, which was associated with an ability to reduce reactive oxygen species.

"This is the first research that has looked at the relationship between these species of compounds and different antioxidant abilities in these plants. We found significant positive relationships between the concentration of individual compounds measured and certain antioxidant abilities. This is important for understanding how these plant foods can be used to protect our brains and bodies from damage," May said.

"Understanding the phytochemical profile of plant foods is vital to understanding how they benefit and boost our brain health. There is a lot of potential to use plant-based foods as part of a toolkit to manage conditions caused by neuroinflammation and oxidative stress, such as neurodegenerative disease. They are also just great for our general health."

More information: Naomi May et al, Characterisation and quantification of phenolic, anthocyanidin and terpene species in plant foods and plant food-based complementary products with antioxidant and neuroprotective properties, Food & Function (2024). DOI: 10.1039/D4FO02942A

Journal information: Food & Function 

Provided by University of Wollongong