Molecular Biology

The Structure and Function of Lignin in Plant Cells

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"The Structure and Function of Lignin in Plant Cells"
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Lignin is a natural polymer which confers flexibility as well as strength to cellulose in the cell wall of the plant cell. Lignin resists attacks by many microorganisms.

What is known as "fiber" is actually the amount of cellulose and lignin present in a plant. Lignin is not digestible.

It is the lignin found in wood which causes the need for a second pulping method known as, chemical pulping. During chemical pulping, a calibrated chemical/water solution dissolves the lignin. Lignin binds fibers and causes a discoloration of paper. Once the lignin is gone, paper is less prone to discoloration.

There is a saying about very strong people, comparing them to "Oaks", in their stability and unbreakability. However, it is the ability to bend without breaking which defines psychological strength and this principle is also applicable to plants, due to lignin within the plant cell.

If ever there was a resisting element to plants, barring the poison ones, it would be lignin. Lignin is like the perfect otherworldly soldier who stays to the swallowed end, but like a catalyst, it is not changed.

All living things, even plants have a will to survive. That of course does not stop me from eating potatoes and broccoli.

Think of lignin as the chief non-carbohydrate constituent of wood and other plants, like grass.

Like any vital component, lignin is a three dimensional polymer. Lignin is often referred to as the "cement" of cellulose for it's ability to effectively bind fibers, and yet, it is also called "nature's plastic" for it's flexibility.

Via mild alkaline oxidation, of lignin sulphonates, vanillin can be obtained for flavoring and odoring. If you've ever smelled that nuance of sweetness in an old book, you've gotten a whiff of lignin, that old soldier wafting it's memory from the volumes of knowledge.

Lignin, must of course be expelled from an animals system, because the build up of it would eventually lead to blockages. So, lignin, which is ingested, but cannot be digested ends up in feces.

Nevertheless, some organisms have evolved to be able to break down lignin and this is of course important to the ecosystem, so far as nutrient recycling. Unfortunately, it is lignin in clover and other grasses which causes cattle to emit gases into the atmosphere.

It is as if the old soldier finds ways to make one sorry for eating a plant.

Scientists have been experimenting with ways to reduce lignin in trees and not being satisfied with the outcome are now attempting to re-engineer lignin molecules.


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