Textile microbiology

(microbiology) That branch of microbiology concerned with textile materials; deals with microorganisms that are harmful either to the fibers or to the consumer, and microorganisms that are useful, as in the retting process.

That branch of industrial microbiology concerned with textile materials. Most of the microorganisms on textiles—the fungi, actinomycetes, and bacteria—originate from air, soil, and water. Some of the microorganisms are harmful to either the fibers or the consumer. They may decompose the cellulose or protein in the fiber or affect the consumer's health. Since the minimum moisture content for microorganism development is 7%, dry storage is an effective prevention measure. Some of the microorganisms are useful, for example in the retting process, in which fibers are liberated from the stalks of such fiber plants as flax, hemp, and jute.

In principle, retting consists of a breaking down of pectic substances between the cell walls (middle lamellae) of the individual cells of the tissue surrounding the bundles. As a result, the bundles become separated from the surrounding tissue and can then easily be extracted mechanically. In water retting, the stalks are immersed in cold or warm, slowly renewed water, for from 4 days to several weeks. The active organism is Clostridium felsineum and related types, which break down the pectin to a mixture of organic acids (chiefly acetic and butyric), alcohols (butanol, ethanol, and methanol), carbon dioxide (CO₂), and hydrogen (H₂). In dew retting the stems are spread out in moist meadows; here the pectin decomposition is accomplished by molds and aerobic bacteria with the formation of CO₂ and H₂O. See also Industrial microbiology; Textile chemistry.