Deconstructing Cotton Fiber's Biochemical Building Blocks

Researchers are closing in on the biochemical building blocks behind cotton lint's success as a durable, widely-used natural plant fiber. Their findings could help further improve strength, uniformity and other fiber properties desired by textile and clothing makers.

Defects in processed cotton fabrics resulting from lint fiber imperfections cost U.S. textile makers millions of dollars annually. One approach taken by Glycozyme, Inc.,of Irvine, Calif., and Agricultural Research Service scientists is to model lint fiber's biochemical and physiological development in cotton bolls.

By sampling bolls from California, Mississippi and South Carolina cotton fields, they're compiling data to show how environmental factors like day length, drought, or temperature changes affect fiber properties--and imperfections like fiber thickness variations that can later plague lint processing. With such information, cotton growers could better predict their crop's chief fiber properties before harvest and later market it accordingly.

Glycozyme's Allen Murray is doing the work cooperatively with ARS' Judith Bradow and Gretchen Sassenrath-Cole. They're also investigating the role of biochemical building blocks, called oligomers, discovered in cotton by Murray in 1997. Like cellulose, oligomers are moderately long chains of carbohydrate molecules. But they're shorter and connect to protein.

The researchers are building a case that, during development, oligomers become an essential construction material that coincides with the biosynthesis of cotton fiber cells’ secondary wall. The data so far suggests the carbohydrate/protein duo serves the purpose of "scaffolding" and "cement" where cellulose--the "bricks"--forms, creating lint fiber's secondary wall. Too little cellulose there, such as in immature fibers, and not enough dye may get absorbed. Or, the fibers become snarled to form tiny knots, called neps, during spinning.

Murray will present a paper on the work at the American Chemical Society meeting March 26-30 in San Francisco, Calif. On the farm, measuring a cotton fiber's oligomer content and distribution can help reveal stress caused by drought or other environmental factors. In field studies, this measure of stress is 7 to 10 days sooner than conventional methods.

Scientific contacts: Judith Bradow, ARS Cotton Fiber Quality Research Unit, New Orleans, La., phone (504) 286-4479, fax (504) 286-4419, [email protected]; Gretchen Sassenrath-Cole, Application and Production Technology Research, Stoneville, Miss., phone (662) 686-3289, fax (662) 686-5372, [email protected]; Allen Murray, Glycozyme, Inc., Irvine, Calif., phone (949) 261-9664, fax (949) 261-9078, [email protected].