Production of rhamnolipid biosurfactants by Pseudomonas aeruginosa
碩士 === 大葉大學 === 食品工程研究所 === 83 === In this study,Pseudomonas aeruginosa CCRC11633 and Pseudomonas fluorescens CCRC14347 produced biosurfactants. The result of showed that P.aeruginosa had the highest level of biosurfactant secretion among tested strains....
Main Authors: | , |
---|---|
Other Authors: | |
Format: | Others |
Language: | zh-TW |
Published: |
1995
|
Online Access: | http://ndltd.ncl.edu.tw/handle/13182199112713214624 |
Summary: | 碩士 === 大葉大學 === 食品工程研究所 === 83 === In this study,Pseudomonas aeruginosa CCRC11633 and Pseudomonas
fluorescens CCRC14347 produced biosurfactants. The result of
showed that P.aeruginosa had the highest level of biosurfactant
secretion among tested strains. Nutrient broth and five
different carbon sources(glucose、surcose、olive oil、 soybean
oil、n-paraffin )media were tested on shaker-flask scale for
culturing P. aeruginosa with olive oil and soybean oil as
carbon source,the surface tension of P. aeruginosa
fermentation broth were red uced to 35.0 dyne/cm and the
surface tension of fermemtation broth were reduced to 26.2 dyne/
cm. When glycerol- peptone were applied in the medium. We used
spectrophotometer to monitor the secretion of rhamnose of the
P. aeruginosa,the yield were 6.47 g/L. Use two-stage culture,
the yield were 13.21g/L. The optiumn cultural condition: with
fermentation temperature of 30 ℃、pH7.0、300mL/L of medium、5%
Glycerol as carbon and 4% peptone as nitrogen source. The
biosurfactants produced by P. aeruginosa were identified by TLC
as rhamnose,the CMC is 0.11 mL/dL and were stable at high
temperature(121 ℃ for 20mins)and different pH value
ranges(1-14). Ultrafiltration rather than extraction were
better in recovery of rhamnolipid. Anion exchange
chromatography on DEAE-Sephacel was chosen for further purifi-
cation. The rhamnolipid was eluted from the matrix with 0.8M
NaCl Tris-HCl buffer and the surface tension of this elution
was 26.7 dyne/cm. Ten μ l of rhamnolipid showed growth
inhibition to Escherichia. coli、Bacillus cereus、Bacillus
subtilis and Staphylcoccus aureus. Comply with rhamnolipid
concertration increase, the inhibition ring augment for E.
coli and Staphylcoccus aureus. Using oil-containg medium,
biosurfactant producing strain with low surface tension(30.1
dyne/cm)was isolated from Chang-Hwa and Jia-yi area.
|
---|