title: Stimulatory effects of biosurfactant produced by Pseudomonas aeruginosa BSZ-07 on rice straw decomposing.
abstract: Biosurfactant, produced by Pseudomonas aeruginosa BSZ-07, was added to the rice straw decomposing process to enhance the production of reducing sugars. Observed by Fourier Transform InfraRed (FT-IR) and Nuclear Magnetic Resonance (NMR) analysis, the purified biosurfactant was considered as a mixture of RL1 and RL2, which are two different types of rhamnolipids. Two different adding methods, adding the purified rhamnolipid and the on-site production of it were compared. The results showed that 0.5 g/L was the optimum concentration for adding purified rhamnolipid and the optimum temperature for on-site production was 30 degrees C for the first 48 h and 34 degrees C for the next 48 h. Under the optimum conditions, these two adding methods could improve the production of reducing sugar to 2.730 and 2.504 g/L, which was 22.30% and 12.20% higher than that of the rhamnolipid-free sample, respectively, which indicated that both of them were more effective than any other kind of surfactant discussed in this article. As the on-site production of rhamnolipid could omit the purification process, thus reducing the production cost effectively, it seemed to be a prospective adding method of the biosurfactant for enhancing rice straw decomposing.
authors.affiliation: Department of Environmental Science and Engineering, Harbin Institute of Technology, Harbin 150090, China. zhangqiuzhuo@126.com
authors.forename: Qiuzhuo
authors.initials: Q
authors.lastname: Zhang
authors.forename: Weimin
authors.initials: W
authors.lastname: Cai
authors.forename: Juan
authors.initials: J
authors.lastname: Wang
mesh_terms: D004305:Dose-Response Relationship, Drug; D005285:Fermentation / Q000187:drug effects*; D006017:Glycolipids / Q000096:biosynthesis* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D012275:Oryza / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013501:Surface-Active Agents / Q000378:metabolism* / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors
chemical_list: D006017:Glycolipids; D013501:Surface-Active Agents; C418382:rhamnolipid