Читать книгу Biosurfactants for a Sustainable Future - Группа авторов - Страница 44

Bacteria plays an essential role in the biosynthesis of biosurfactants on the industrial scale. Pseudomonas has been reported to be the leading genus, followed by others for biosurfactant production [30]. Pseudomonas nautica, isolated from a Mediterranean coastal area, was reported to produce extracellular biosurfactants with excellent emulsifying behavior [31]. Based on the various kinds of carbon as well as hydrocarbons, microorganisms can yield different types of emulsifiers [32]. A group of researchers [33] proved this practically by providing various hydrocarbons as a carbon source to hydrocarbon‐degrading Pseudomonas fluorescens for the biosynthesis of trehalose lipid‐o‐dialkyl monoglycerides‐protein emulsifier [34].

Bacillus sp. are mostly recognized for the biosynthesis of lipopeptides (lipid connected to a peptide) [35], lichenysin (anionic cyclic lipoheptapeptide biosurfactant), surfactin (bacterial cyclic lipopeptide) [36], lipid–protein complex [37] and subtilisin (a protein‐digesting enzyme) [38]. In 1983, Jenneman et al. [39] documented the application of thermotolerant and halotolerant Bacillus licheniformis JF2 in microbial‐enhanced oil recovery. Similarly, Bacillus brevis and Bacillus polymyxa were documented to produce a large number of cyclic lipopeptides by using agro wastes [40]. Horowitz and Griffin [41] reported that biosurfactant BL‐86, which has been produced by B. licheniformis, is useful for various applications and is capable of remediating heavy metal contaminated soil. BL‐86 is capable of reducing surface tension and emulsification of hydrocarbons.

There have already been 160 biosurfactants producing bacterial strains identified in soils contaminated with petroleum [12, 42, 43]. Abouseoud et al. [44] reported the potential of P. fluorescens Migula 1895‐DSMZ for biosurfactant production from olive oil. In their study, it was concluded that P. fluorescens Migula 1895‐DSMZ is the primary organism responsible for the production of biosurfactants from various industrial wastes.

Acinetobacter sp. are readily available in nature and are among the most frequently available marine microbes in ocean habitats [45]. Due to their separate existence, Acinetobacter sp. have received significant attention from many scientists in the last few years. Hydrocarbon degrading Acinetobacter sp. perform a significant role in the bioremediation processes of various hydrocarbons in the natural environment [46]. Choi et al. [47] isolated Acinetobacter calcoaceticus RAG‐1, which produces a commercially important biosurfactant called “emulsan,” from the Mediterranean Sea, by using oil industry waste.

Rhodococcus sp. are prominent for producing glycolipids like surface‐active molecules [48]. Peng et al. [49] reported the abundance of Rhodococcus erythropolis strain 3C‐9 in Xiamen Island coastal area soil, and they can remediate the oil‐contaminated soil in the area. A few scientists [13, 50] documented the production of various types of biosurfactants (glycolipid, polysaccharides, free fatty acids, and trehalose dicorynomycolate) by R. erythropolis [51] and Rhodococcus sp. [52].