| In this study, Paenibacillus polymyxa SYX-1 was used to rapidly degrade rice straw. The formed biofilm was characterized by the combination of confocal laser scanning microscopy（CLSM） and laser Raman spectroscopy. The distribution patterns of proteins, α-polysaccharides, cellulose, total cells, and dead cells in rice straw were simultaneously visualized using CLSM after labeling by fluoresceinisothiocyanate（FITC）, concanavalin A（Con A）, calcofluor white（CW）, STYO 63, and SYTOX blue, respectively. The results demonstrated that SYX-1 was colonized on the surface of straw and formed a good biofilm during the degradation process from 0 to 13 days. A lignocellulose structure was observed obviously in rice straw at 0 day but obscured after cultivation of 13 days, supporting the degradation of rice straw by SYX-1. The laser Raman spectra demonstrated that the degradation of rice straw mainly occurred at the bands of 1580 cm-1 and 1590 cm-1, which is belonged to the stretch vibration modes of amide groups. Therefore, the combination of multiple fluorescence labeling-CLSM observation and laser Raman spectroscopy could be used as a suitable tool to characterize the architecture and function of biofilm. Knowledge on the architecture and function of biofilm contributes to our understanding of the degradation and utilization of lignocellulose biomass and provides novel information for engineering applications and scientific research. |
