ISOLATION OF THERMOPHILIC XYLANOLITIC BACTERIA FROM WOODY-CHIP PILE

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgemviennagreen.org, SGEM2017 Vienna GREEN Conference Proceedings, ISBN 978-619-7408-29-4 / ISSN 1314-2704, 27 - 29 November, 2017, Vol. 17, Issue 63, 273-280 pp; DOI: 10.5593/sgem2017H/63/S25.035

ABSTRACT

To increase the efficiency of conversion of plant raw materials, a search for new enzymes is required. The hydrolysis of xylan using industrial xylanases is widely used in the production of bleached cellulose. However, an increase in activity, selectivity and thermostability of enzymes is relevant for modern biotechnology.
Recently, the sources of bacteria that have important practical significance are very diverse: from sea depths to volcanoes. But there are also accessible habitats, for example deposits of wastes large-scale plants.
The paper presents data on thermophilic cells were isolated from woody-chip pile, Arkhangelsk, Northwestern Russia. A bacteria that could tolerate high temperatures was characterized by morphology, biochemistry and sequencing of 16S rRNA gene. The isolate was screened for xylanase activity.
Growing bacteria on agar plate and liquid fermentation with various carbohydrate sources. Optimum conditions for bacterial growth were: initial pH 7.0-8.0, temperature 57-63 °C. Growth of bacteria was observed in the range of 55-70 °C. Selected strains were Gram-positive rods with terminal spores, and fermented sugars. Growth rate high density of microorganisms after 4 hours cultivation on rich media is 109 cells.
The quantitative determination of the activity of the thermostable xylanase was measured by Nelson-Somogyi methods using oat spelt xylan. The most active strains related to Parageobacillus sp. were selected.

Keywords: xylanase, thermophiles microorganism, woody-chip pile, Parageobacillus.