Molecule of the Month: December 2011
Viscumin (mistletoe) Malvidin (wine)
Viscumin is a highly toxic protein found in European and Asian species of mistletoe. When ingested it causes blurred vision, nausea, dramatic changes in blood pressure, abdominal pain, diarrhoea and in severe cases, death.
To ancient British druidic cultures, Mistletoe was a sacred plant and was used to ‘cure’ many illnesses from infertility to epilepsyIt is now being investigated as a potential anti-cancer drug.
Malvidin is one of the anthocyanins responsible for the colour of red wine. The positive charge on the molecule means that the colour is sensitive to changes in pH. The more acidic the wine is, the more of the malvidin is positively charged and the redder the colour.
SO2 (sulfur dioxide) is a natural by-product of the fermentation process. High levels of sulfur dioxide in the wine can cause it to bleach as the sulfonated cation is colourless.
Merry Christmas from the Dean Close Chemistry Department!