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The concept of manufacturing valuable bacterial nanocellulose (BNC) from plant raw materials having a zero prime cost is substantiated. The process flowsheet involves the chemical transformation of the feedstock to obtain a pulp; enzymatic hydrolysis of the pulp to furnish a solution of reducing sugars, chiefly glucose; preparation of a nutrient broth based on the enzymatic hydrolysate; biosynthesis of nanocellulose microfibrils by the symbiotic Medusomyces gisevii Sa-12 culture; and purification of BNC. BNC has for the first time been synthesized from oat hulls and has a high degree of crystallinity of 88 ± 5% and is composed of 99% Iα-allomorph.

The effect of culture conditions on the bacterial cellulose (BC) yield synthesized by symbiotic culture Medusomyces gisevii Sa-12 grown in synthetic nutrient medium was studied for the first time. The conditions providing the maximum yield of bacterial cellulose were evaluated: the initial glucose concentration in the culture medium was 20-25 g/L, the temperature was 24-27°C, the ratio of the nutrient medium to the air volume was 1 : 10, and the content of the black tea extracts comprised 1.6-4.8 g/L. A sample of chemically pure BC with the following characteristics was obtained under the selected culture conditions: moisture--99.0%, degree of polymerization--4800, average width of microfibrillar ribbons--30.6 nm, degree of crystallinity--86%, and the content of triclinic modification Ia--98%. [ABSTRACT FROM AUTHOR]

Pulps prepared from oat husks via a method combining prehydrolysis, alkali delignification, and nitric acid treatment were demonstrated to possess high fermentability upon hydrolysis using multienzyme preparations, such as BrewZyme BGX and CelloLux-A. A dependence of the increment of the yield of reducing substances on the initial substrate concentration ranging from 15 to 120 g/dm was studied. The final yield of reducers at 72 h was shown to decline from 88 to 65% with an increase in the initial concentration of the substrate. [ABSTRACT FROM AUTHOR]