Biosurfactant Production by Bacillus strains isolated from sugar cane mill wastewaters

Abstract

Biosurfactants possess diverse chemical properties and provide important characteristics to the producing microorganisms, which can act as surface-actives and emulsifiers of hydrocarbon and others water insoluble substances. Most of them are lipopeptides synthetized by Bacillus. This study evaluated the biosurfactant production by strains of Bacillus previously obtained from liquid residues of sugar-alcohol industry. The bacterial isolates LBPMA: BSC, BSD, J1, J2 and L1 were cultivated in medium that induces production of biosurfactants (Landy medium). During 48 h of incubation, at intervals of 12 h, the total contents of proteins, reducing carbohydrates and surfactant activity of the filtrated growth media free of cells were evaluated. The results showed that these strains use glucose as a source of carbon, energy and for synthesis of surfactant. In this medium (24 h), the best producer of biosurfactant was the strain LBPMA-J2, molecularly identified HIGHLIGHTS • Interest in biosurfactants has increased in the last two decades. • Surfactin from Bacillus is one of the most effective biosurfactants. • Bacillus species are known as the main producers of extracellular enzymes. • Isolation of new strains is strategic for several fields of biotechnology. Santos, E.C.L.; et al.

Biosurfactant activity of phylloplane bacteria from an ornamental plant, Colocasia esculenta L.

“…Some strains of the B. cereus group are known to be pathogenic bacteria, but some may be classified as non-pathogenic and known as producers of biosurfactants especially from the environment. Some strains of B. cereus are known as a beneficial group in the agriculture and food industry sectors along with its close relatives such as Bacillus anthracis, Bacillus thuringiensis, Bacillus cytotoxicus, Bacillus mycoides, Bacillus pseudomycoides, and Bacillus weihenstephanensis (Santos et al 2019). The genus Bacillus has previously been reported as one of the genera of bacteria capable of producing biosurfactants such as Bacillus siamensis , and Bacillus firmus , Bacillus subtilis (Hussain and Khan 2020d), etc.…”

“…The feature is due to the fact that members of Bacillus generate resistant endospores under stressful conditions (Alyousif et al 2020). Santos et al (2019) added that the genus Bacillus has a high level of resistance to various physical disturbances: such as wet and dry heat, UV and gamma radiation, and extreme environmental conditions.…”

“…The structure of lipopeptides is generally made up of heptapeptides and hydroxy fatty acid chains. The main classes of lipopeptides are surfactin, iturin and fengycin (Basit et al 2018;Santos et al 2019). Structurally, biosurfactants have a more complex structure than synthetic surfactants because they are composed of a combination of biomolecules such as proteins, carbohydrates and lipids.…”