Characterization and Identification of Xylanolytic Bacteria Stenotrophomonas sp. EL-8 Isolated from Seagrass Substrates in Enggano Island

Abstract

Xylanases are hydrolytic enzymes that degraded xylan into xylooligosaccharide and xylose. Nowadays, the xylanases play a major important role in the industrial products, in the field of paper, pulp, food, beverage, pharmaceutical and animal feed. This study was to characterize and optimize xylanase produced by Stenotrophomonas sp. EL-8 isolated from the seagrass substrates in Enggano Island. The seagrass substrates were collected from Banjar Sari Beach, Enggano Island. Isolation of bacteria from seagrass substrates using 0.5% beechwood xylan agar medium. The isolates were screened by morphological characters. Colonies which produced clear zone were presumed as xylanolytic bacteria furthermore they were selected for determination of xylanase enzyme activity. The selected potential xylanolytic isolate was identify based on 16S rRNA. The results of this study showed that a total of 22 bacteria were isolated. Based on clear zone screening, EL-8 isolate indicated more potentially than the other 21 isolates. The crude enzyme production of EL-8 showed the highest activity at 18 hours incubation with the enzyme activity of 0.831 U/mL. This crude enzyme optimally worked at pH 5, temperature 45 °C with the enzyme activity 2.836 U/mL. EL-8 isolate has a close relationship with Stenotrophomonas sp. EL-8 based on 16S rRNA gene identification.