Lignins matter

Let us consider other natural habitats of propionic acid bacteria. In grasses used as fodder for livestock the content of cobalt is often below a certain limit (0.08 ppm), so that if cobaltous salts are not added to feeds, animals will suffer from cobalamin deficiency. Animals are supplied with corrinoids mainly through the biosynthetic activity of bacteria. If 1 mg of cobalt a day is added to the feed, then the content of cobalamins in the dry residue of lignin matter in rumen is 0.59 to 1.0 jag/g. When no cobalt is added, the content of cobalamins is lowered by an order of magnitude, to 0.081-0.108 ig/g (Smith and Marston, 1970) correspondingly, the content of vitamin in all animal tissues and fluids is low. Therefore, the concentration of vitamin in meat, milk and other products obtained from the animal will depend on the content of cobalt in the feed. 

In wooden tubs, the maintenance of a sanitizer residual becomes compHcated due to the leaching of tannins and other organic matter from the wood into the water. The sanitizer demand of these substances must be overcome in order to maintain proper residual concentrations. As the tub ages, the leaching of these materials decreases, but bleaching of the wood may occur as the lignin (qv) in the wood reacts with sanitizers. 

Cellulose is the most abundant of naturally occurring organic compounds for, as the chief constituent of the eell walls of higher plants, it comprises at least one-third of the vegetable matter of the world. The cellulose eontent of such vegetable matter varies from plant to plant. For example, oven-dried cotton contains about 90% cellulose, while an average wood has about 50%. The balance is composed of lignin, polysaccharides other than cellulose and minor amounts of resins, proteins and mineral matter. In spite of its wide distribution in nature, cellulose for chemical purposes is derived commerically from only two sources, cotton linters and wood pulp. 

Although tannins and lignins have been available for well over 50 years (and perhaps twice as long), they remain very useful as low-cost, general-purpose particulate-matter dispersants. Both tannins and lignins are coproducts of the wood pulping process... 

No matter what its state is in the cell W all vivo, when the lignin molecule is released from its attachment to the cellulose matrix, either by breaking its tendril-like bonds (e.g. by pulping) or destruction of the cellulose matrix (c.g. by hydrolysis with acids or enzymes), it rolls up to a globular entangled mass something like tumbleweeds. 

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