I love blueberries. I’ve opened many clamshells of the tiny, tart, antioxidant fruits in my lifetime—sometimes to spoon them out into a bowl of fresh cream and demerara sugar and dive right in, and sometimes to have my heart sink at the sight of those beautiful little berries covered in grey mold. So imagine my delight to hear that researchers at the Kunming Institute of Botany, Chinese Academy of Sciences, have derived an entirely natural preservative from blueberries’ garden neighbour, the sunflower, which fights that destructive fuzz!
Sunflowers are already grown and harvested commercially for their seeds and the oil they produce. The team zeroed in on the chief waste product of this industry—the stems. They followed a hypothesis that the pathogen-fighting compounds within them that kept the sunflowers safe might transfer to other plants. The results were kind of stunning and showed a great deal of promise for non-pesticide antifungals in the agricultural industry.
“The researchers used methanol and ethyl acetate to prepare extracts from sunflower stems. They then isolated and identified the components in these extracts, focusing on diterpenoids, which are known to have biological activity. They found 17 diterpenoids, including four previously unknown compounds. Most of the diterpenoids showed activity against gray mold. Four of the compounds—including two of the newly identified ones—were effective at destroying the plasma membrane of this fungus, causing its cells to leak and preventing it from forming biofilms. In another test, the researchers briefly wet blueberries with the receptacle extracts, then dried the fruits and injected them with mold spores. Over a period of six days, the receptacle extracts protected almost half the berries from mold growth.”
I’m so excited at the prospect of never losing another precious berry to post-picking decay—especially if it’s not at the hands of a toxic fungicide. Plus, this is yet another clever use of a waste product for maximum benefit. Here’s hoping we see it on our tables (and in our bowls full of cream and sugar) soon!