The practice of eating Paan/Catechu is ubiquitous in the Indian sub-continent. Paan is a traditional mouth freshener with the principle ingredients as areca nut, slaked lime, betel leaf and katha. It is the combination of katha and slaked lime in paan that gives it the signature red colour for which it is famous. However, chewing Paan produces excess saliva, which needs to be spat out from time to time. Rampant spitting after consumption of Paan is a widespread nuisance in India as well as the much of the sub-continent. Physical methods of cleaning (scrubbing etc) are costly and time-intensive to implement on a city-wide scale. The present methods of cleaning paan stains involve the use of hazardous chemicals and acids. We found that the Indian Railways spend a whopping Rs.36 crore (approximately 6 million USD) on cleaning paan stains in Mumbai region alone.


Our attempt to address the above sociological problem is in the form of our genetically engineered machine Catechewing coli which is an effective, economical, efficient and ecologically safe alternative to the present paan-stain cleaning methods.


We found that compounds responsible for the characteristic red colour of paan are tannic acid and polyphenols. Our view was to find potential microbial enzymes known to degrade the flavan 3,4-diol bonds in polyphenols. Further, the gene sequence coding for the most suitable enzyme, capable of degrading paan stains effectively, will be cloned & can be successfully incorporated into our Genetically Engineered Machine.


As our project directly involves the society at large, we interacted with paan vendors, cleaners, housekeeping persons. An interaction with the paan vendors gave us an idea of color producing components in paan. Interaction with various janitors and their managing companies gave us a brief idea regarding the methods already in use for cleaning paan stains and what threat they are exposed to, which motivated us to think of a safe alternative method to deal with this nuisance.