About polyphenols

Biological deterioration of wood is a major concern for the timber industry because of the economic losses it causes to wood in service or in storage. Fungi, insects, termites, marine borers and bacteria are the main biodegraders of wood.

Cellulose is the main structural component of wood and also the main food of insects and decay fungi.

 

Polyphenols are secondary metabolites of plants and are generally involved in defence against ultraviolet radiation or attack by pathogens.

 

Polyphenols are natural compounds found largely in fruits, vegetables, cereals and beverages. In food, polyphenols can contribute to bitterness, astringency, colour, flavour, odour and oxidative stability.

Furthermore, epidemiological studies and associated meta-analyses strongly suggest that long-term consumption of diets rich in plant polyphenols offers protection against the development of cancers, cardiovascular diseases, diabetes, osteoporosis and neurodegenerative diseases.

 

Flavonoids, a type of polyphenol, have an important effect on the durability of wood.

The general structure of flavonoids comprises a C15 (C6-C3-C6) skeleton joined to a chromane ring. Here are some examples:

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Flavonoids protect heartwood against fungal colonisation through a dual function: fungicidal activity and being excellent free-radical scavengers (antioxidants). The radical-scavenging activity is particularly important because fungi use radicals to disrupt cell walls. These polyphenols also have a repellent effect on termites.

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For more information: https://pdfs.semanticscholar.org/f654/d5678a49ebff62c73323f247b903e5ce2c26.pdf