Isolation and characterization of two glycolipopeptids biosurfactants produced by a Lactiplantibacillus plantarum OL5 strain isolated from green olive curing water.

Microbial surfactants are natural amphiphilic compounds with high surface activities and emulsifying properties. Due to their structural diversity, low toxicity, biodegradability, and chemical stability in different conditions, these molecules are potential substitutes for chemical surfactants; their interest has grown significantly over the last decade. The current study focuses on the isolation, identification, and characterization of a lactic acid bacteria that produce two forms of biosurfactants. The OL5 strain was isolated from green olive fermentation and identified using MALDI/TOF and DNAr16S amplification. Emulsification activity and surface tension measurements were used to estimate biosurfactant production. The two biosurfactants derived from Lactiplantibacillus plantarum OL5 presented good emulsification powers in the presence of various oils. They were also shown to have the potential to reduce water surface tension from 69 mN/m to 34 mN/m and 37 mN/m within a critical micelle concentration (CMC) of 7 mg/ml and 1.8 mg/ml, respectively, for cell bound and extracellular biosurfactants. Thin layer chromatography (TLC) and FT-IR were used to analyze the composition of the two biosurfactants produced. the obtained data revealed that the two biomolecules consist of a mixture of carbohydrates, lipids and proteins. We demonstrated that they are two anionic biosurfactants with glycolipopeptide nature which are stable in extreme conditions of temperature, pH and salinity.

Potential application of Bacillus subtilis SPB1 biosurfactants in laundry detergent formulations: Compatibility study with detergent ingredients and washing performance.

Surfactants play a very important role in laundry and household cleaning products ingredients. In this research, the application of lipopeptide biosurfactants, produced by Bacillus subtilis SPB1, in the formulation of a washing powder was investigated. The SPB1 biosurfactant was mixed with sodium tripolyphosphate as a builder and sodium sulfate as filler. The efficiency of the formulated detergent composition with different washing conditions to remove a stain from cotton fabric was examined. The results showed that the formulated detergent was effective in oil removal, with optimal washing conditions of pH, temperature, striate and time of washing system of 7, 65°C, 1000 RPM and 60 min, respectively. A comparative study of different detergent compositions (biosurfactant-based detergent, combined biosurfactant-commercial detergent, and a commercial detergent) for the removal of oil and tea stains, proved that the bio-scouring was more effective (>75%) in terms of the stain removal than the commercial powders (<60%). Moreover, the results demonstrated that the biosurfactant acts additively with a commercial detergent and enhances their performance from 33 to 45% in removing oil stain and from 57 to 64% in removing tea stain. As a conclusion, in addition to the low toxicity and the high biodegradability of the microbial biosurfactants, the results of this study have shown that the future use of this lipopeptide biosurfactant as laundry detergent additive is highly promising.

Potential application of Bacillus subtilis SPB1 lipopeptides in toothpaste formulation.

Toothpaste is a gel dentifrice used with a toothbrush as an accessory to clean, keep and promote oral hygiene. The literature review suggests that there are many different formulations of toothpastes and that each of their individual components present specific functions. The concentration of the toothpaste ingredients must be appropriately chosen taking into account the purposes of the toothpaste. Biosurfactants are considered as suitable molecules for application in many formulations such as in toothpaste one. In the present work, two dentifrice formulations were investigated and their efficiencies were tested using chemical surfactant agent and lipopeptide biosurfactant isolated from Bacillus subtilis SPB1. The physicochemical properties were analyzed considering several tests mainly spreading ability, water activity, pH, foaming and cleaning tests. The obtained results indicated that the SPB1 biosurfactant was as efficient as the chemical surfactant confirming its potential utilization in toothpaste formulation compared to the commercial one. The evaluation of the antimicrobial activity of the formulated dentifrice was carried out against eight bacteria. The results demonstrated that the biosurfactant-based product exhibited an important antimicrobial activity, which was very effective against Enterobacter sp and Salmonella typhinirium.