**4.3 Production of biosurfactants by** *Pseudomonas aeruginosa*

Biosurfactants are a structurally diverse group of surface-active substances produced by microorganisms. The microorganisms that produce biosurfactants include *Pseudomonas*, *Bacillus*, *Micrococcus*, *Mycobacterium*, *Rhodococcus*, etc.

All biosurfactants are amphiphiles which consist of two parts: a polar (hydrophilic) moiety and nonpolar (hydrophobic) group [48].

The advantages of biosurfactants over chemically synthesized surfactants includes but not limited to; pH tolerance, less toxicity to the environment, biodegradability, better foaming properties, and them being able to be produced from agro-based industrial wastes [49].

Generally, biosurfactants have an ability to stabilize emulsions in various industrial applications [50] and are well-used in the food and pharmaceutical industries to achieve stability of emulsions. In addition, they have been applied in polluted water and soil during bioremediation in order to reduce interfacial tension, and it enhances the polar and nonpolar moieties to mix up.

Rhamnolipids are the major type of biosurfactant produced by *Pseudomonas aeruginosa* strain. Rhamnolipids are well-studied glycolipids secreted by *Pseudomonas aeruginosa* and have been found to have excellent surface activity [25] (**Figure 2**).

Incorporating rhamnolipids into remediation process enhances the solubility and elimination of these contaminants by improving oil biodegradations rates. Comparative study of biosurfactants for washing soil contaminated with crude oil was carried out where rhamnolipids showed a high degradable capacity; 80% of oil were degraded. Oil washing experiments by a combination of 10 g/l NaCl, 5.0 g/l n-butyl alcohol, and 2.0 g/l rhamnolipid provide very high oil extraction rates [52–54]. Even though rhamnolipids are the preferred enhancers for petroleum hydrocarbon soil pollutant degradation and have shown potentials to facilitate the bioremediation of soil contaminated by hydrocarbons, it has been suggested that their application must be evaluated carefully to reduce their exhibition on antimicrobial activity [55–57].

**Figure 2.**

*Biosurfactant-assisted bioremediation of crude oil by indigenous bacteria. Isolated from Taean beach sediment [58].*

**105**

provided the original work is properly cited.

\*Address all correspondence to: orjifa@yahoo.com

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

1 Department of Biotechnology, Federal Institute of Industrial Research, Lagos,

2 Department of Chemical, Fiber and Environmental Technology, Federal Institute

3 Department of Microbiology, Modibbo Adama University of Technology, Yola,

, Ukaegbu Gray Nneji1

and Lawal Oluwabusola Mistura1

, Ajunwa Obinna3

,

*The Beneficial Roles of Pseudomonas in Medicine, Industries, and Environment: A Review*

Basically, strains of *Pseudomonas aeruginosa* have been widely implicated as clinical pathogens both in humans and in veterinary cases. In addition, they have been identified to be the causative agents of wound sepsis, septicemia, and nosocomial

However, this chapter took a different dimension toward the beneficial roles of *Pseudomonas aeruginosa* strains in medicine, industries, and environment. The hopes of a clean environment through biodegradation of xenobiotics and bioremediation of hydrocarbon-impacted ecosystems are high with the use of *Pseudomonas aeruginosa*. In the industries, *Pseudomonas aeruginosa* holds a lot of practical promises toward production of intermediate products including metabolites such as

Typically, in Nigeria and other developing countries, most of these materials from *Pseudomonas aeruginosa* are imported, and this does not encourage growth and development. Thus, local production of these intermediate products from *Pseudomonas aeruginosa* is adequate to save foreign reserves and promote

*DOI: http://dx.doi.org/10.5772/intechopen.85996*

rhamnolipids, vanillins, lipases, biopigments, etc.

\*, Onyemali Chidi Peter1

**5. Conclusion**

infections.

development.

**Author details**

Orji Frank Anayo1

Adamawa, Nigeria

Nigeria

Ezeanyanso Chika Scholastica<sup>2</sup>

of Industrial Research, Lagos, Nigeria

*The Beneficial Roles of Pseudomonas in Medicine, Industries, and Environment: A Review DOI: http://dx.doi.org/10.5772/intechopen.85996*
