Berea Rocks

Today, after my visit to NASA’s Glenn Research Center, I happened to have dinner at the Cornerstone Brewery in Berea, Ohio, a small suburb of Cleveland. As I strolled around the lake that dominates the town, I stumbled on Berea’s claim to international fame. For over 80 years some of the finest grindstones of the world were exported from Berea. These fine grindstones were cut from the sandstone quarries of Berea. The quarries are now gone and I was standing at the edge of the lake formed by filling one of these quarries. The Rocky River that runs by Berea with flat rocks carelessly strewn across the river bed stands evidence to the monstrous glacial action on the underlying sandstone crust (see picture). As I gazed across the lake, my mind’s eye conjured up images of factory earth performing the immense operations of compaction of the deposits from Lake Erie 300 million years ago to create the gritty sandstone bed on which Berea’s fame was founded.

Saving Humanity from the Scourge of Turmeric Stains

After combing the worldwide web, I was convinced that my commitment to the title cause could alleviate the suffering of numerous “stain-trodden” individuals like myself. The turmeric-stained shirts have been an advertisement of my sloppiness at the dinner table. A section of my wardrobe with stained shirts is now sadly designated for “night time” or “home-use-only”. As for the neckties brilliantly marked with turmeric colored Nike logos, they remain in a state of suspended readiness waiting for an alternate role. After a brand new white shirt took the hit at a recent wedding reception, I was determined to find a solution.

I am happy to report that a simple solution has been found: Hang the stained clothing or article in bright sunlight for a couple of hours and lo and behold the stain disappears with no trace. The UV radiation in sunlight does the work for you; no chemicals are needed ( see photo). Much to my wife’s elation the brand new white shirt was rescued, and a collection of tupperware hidden in the closet with embarrassing stains was emancipated. The world has been saved from the scourge of turmeric stains.

The yellow coloring matter of turmeric is an organic compound named curcumin. The photochemical decomposition (also termed photo-bleaching) of curcumin into colorless compounds is the basis of this magical stain removal process. I am guessing that the light-instability of curcumin could be exploited as an “all –natural” UV blocker. I am wondering if this is indeed the basis of the turmeric-based cosmetic skin creams sold in India. Also, living in Madras several years ago, it was common to see South Indian women “yellow” themselves by smearing turmeric paste on their skin after a bath. Apart from imparting a “glowing” look the yellow coloring probably offers protection from the abundantly present UV light. As the innumerable pharmaceutical benefits of curcumin emerge every day it is clear that the annoying stain, curcumin, is likely to be a much sought after compound for future medicinal preparations.

For those thirsting for the chemistry of photodecomposition of curcumin, here is what I found on curcumin. Curcumin, bis(4-hydroxy-3-methoxyphenyl)-1,6-diene-3,5-dione, absorbs in the UV region of the solar spectrum because of the conjugated double bonds. The compound also exists in its tautomeric enol form (see structural formula in "enol" form). The products ensuing decomposition include benzaldehyde and cinnamaldehyde that are colorless. Interestingly, in another experiment I found that turmeric powder (ground-up dried root) did not decolorize even after exposure to sunlight for many days; however, the yellow extract from curries did decolorize within a few hours. This suggests that curcumin is probably bound as a complex in the turmeric rhizome, and “free” curcumin is extracted into the curries upon cooking.