Welcome to China Surfactant Detergent & Cosmetics, Today is

China Surfactant Detergent & Cosmetics ›› 2022, Vol. 52 ›› Issue (9): 937-944.doi: 10.3969/j.issn.1001-1803.2022.09.004

• Development and application • Previous Articles     Next Articles

The production of high yield biosurfactant rhamnolipid and performance research

Zheng Lanjian,Zang Ying,Lin Tong,Xie Yiwen,Wang Honglei*   

  1. School of Chemistry and Life Sciences, Changchun University of Technology, Changchun, Jilin 130012, China
  • Received:2021-11-13 Revised:2022-08-29 Online:2022-09-22 Published:2022-09-23
  • Contact: Honglei Wang

Abstract:

In order to reduce the cost of biosurfactant in various industries and alleviate the environmental pressure caused by kitchen waste oil, a strain with higher surface activity was screened out through preliminary screening of crude oil medium and re-screening of emulsification index and surface tension measurement from preserved strains with crude oil-contaminated soil in the early stage. In addition, biosurfactant produced by this strain was extracted by acid precipitation-organic solvent extraction, such as acid precipitation-ethyl acetate and acid precipitation-(VchloroformVmethanol=2∶1). Further, the biosurfactant production of this bacteria was optimized by single factor experiment and physical-chemical properties, emulsification and solubilization of biosurfactant were characterized. The experimental results show that a strain with higher surface activity, Pseudomonas aeruginosa AY-1, is obtained through screening. This strain is fermented to produce 5.86 g/L biosurfactant which are characterized as rhamnolipids when the fermentation conditions are 35 ℃, pH=8.0, shaker speed 180 r/min, kitchen waste 50 g/L, sodium nitrate 2 g/L and fermentation time 96 h. The critical micelle mass concentration (cmc) of rhamnolipid produced by this strain is 200 mg/L, and the surface tension of rhamnolipids changes little when rhamnolipid is in all kinds of conditions such as temperature (4-120 ℃), pH=2-12 and the content of NaCl (0-20%, w/%). At the same time, the emulsification performance on different hydrophobic compounds (methylbenzene, n-hexane, cyclohexane, heptane and n-hexadecane) and solubilization effect on polycyclic aromatic hydrocarbons (phenanthrene and pyrene) of rhamnolipids produced by this strain were further studied. Results show that the rhamnolipids produced by this strain have the best emulsification effect on n-hexadecane and significant solubilization effect on polycyclic aromatic hydrocarbons (phenanthrene and pyrene).

Key words: biosurfactant, Pseudomonas aeruginosa AY-1, kitchen waste oil, rhamnolipid, surface activity

CLC Number: 

  • TQ423