12 January - 20 June 2016

Sticking power of plant polyphenols used in new antibacterial coatings

11 Sept 13

Green tea leaves not only can be used to make a good cup of tea, but they also make an excellent antibacterial coating due to polyphenols according to a study by researchers from Northwestern University and published in Angewandte Chemie.  Polyphenols are naturally occurring molecules found in plants whose functions include structural support and defence against bacteria and oxidative damage.  Polyphenols are sticky, and the researchers exploited this useful property, while also retaining some of the compounds’ well-known biological properties.  They made new multifunctional coatings based on tannic acid and pyrogallol – inexpensive compounds resembling the more complex polyphenols found in tea, wine and chocolate.  The coatings – which can stick to virtually anything, including Teflon, could be used on a wide range of consumer, industrial and medical products, from catheters and orthopaedic implants to membranes for water purification and materials used in food processing, packaging and preparation.  For 15 years, the researchers have been developing new biomedical materials, including another coating called polydopamine, also based on phenols, which are found in the sticky glue that marine mussels use to stick to rocks.  Due to their chemical similarities, the researchers wondered if the phenol compounds found in plant-derived red wine, green tea and dark chocolate might have similar sticking power.  Polydopamine has shown great promise as a biomedical coating, but the plant polyphenol-based coatings can trump it in two important ways: The plant polyphenol-based coatings are colourless, so they don’t alter a material’s optical properties, and the compounds used to produce them are roughly 100 times cheaper, in addition to their innate antibacterial and antioxidant properties.

RSSL's Functional Ingredients Laboratory can assay a range of products for polyphenolic components. For more information please contact Customer Services on Freephone 0800 243482 or email enquiries@rssl.com

RSSL’S Functional Ingredients Laboratory has a validated ORAC method which can be used to test the antioxidant capacity of foods.  For more information please contact Customer Services on Freephone 0800 243482 or email enquiries@rssl.com

share this article
RSSL endeavours to check the veracity of news stories cited in this free e-mail bulletin by referring to the primary source, but cannot be held responsible for inaccuracies in the articles so published. RSSL provides links to other World Wide Web sites as a convenience to users, but cannot be held responsible for the content or availability of these sites. This document may be copied and distributed provided the source is cited as RSSL's Food e-News and the information so distributed is not used for profit.

Previous editions

Load more editions

Make an Enquiry