Jul 2026· Journal of Surfactants and Detergents (JSD)· 0 citations· 44 references
TL;DR
The nonhemolytic properties, combined with the ability to lower surface tension and exhibit strong emulsification and oil displacement activities, highlight the potential of this biosurfactant for bioremediation, petroleum industry applications, and biomedical use.
Abstract
Biosurfactants are eco‐friendly, surface‐active compounds produced by microorganisms that have significant industrial and environmental applications due to their biodegradability and low toxicity. This study focuses on the production and characterization of biosurfactants by bacterial strain N19, a novel hydrocarbonoclastic bacterium isolated from Soummam River sediment. The bacterium was cultured in mineral salt medium supplemented with crude oil to stimulate biosurfactant production. Surface tension reduction (23.14 ± 0.12 mN/m), emulsification index (72.13% ± 1.15%), and oil displacement (4.2 ± 0.75 cm) tests confirmed the presence of an effective biosurfactant. Further phenotypic and molecular identification methods, including 16S rRNA sequencing, established the strain's identity as
Rhodococcus ruber
N19. This strain produced 7.92 ± 0.02 mg/mL biosurfactant. Structural characterization using thin layer chromatography (TLC), Fourier‐transform infrared (FTIR) spectroscopy, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF/MS), and liquid chromatography–tandem mass spectrometry (LC–MS/MS), and nuclear magnetic resonance (NMR) analyses revealed that the biosurfactant produced by this strain is a lipopeptide. The nonhemolytic properties, combined with the ability to lower surface tension and exhibit strong emulsification and oil displacement activities, highlight the potential of this biosurfactant for bioremediation, petroleum industry applications, and biomedical use.
Biosurfactant products show significant potential compared to chemical surfactants due to their biodegradability, low toxicity, and eco-friendliness. This study aims to characterize the structures of biosurfactants produced by bacteria isolated from soil and to evaluate their potential in degrading petrol and oil. Biosurfactant-producing strains were selected using oil spreading tests, screening for petrol-degrading bacteria, antimicrobial susceptibility tests, and PCR-based phylogenetic analysis. In total, 5852 colonies and strains of biosurfactant producers were isolated through cultural and molecular methods. These bacteria were classified into three species: Bacillus, Pseudomonas, and Staphylococcus. After biodegradation, the effects of petrol and olive oil, combined with cell-free supernatant, were analyzed, showing an efficient removal rate of 79.59% after 24 hours. Among the bacterial isolates, three strains demonstrated significant oil degradation capacity: Bacillus sp. With a degradation rate of 79.59%, Pseudomonas sp. At 77.55%, and Staphylococcus sp. At 67.3%. In conclusion, biosurfactant-producing bacteria were isolated from soil samples collected at the Center for Bioscience and Nanoscience Research Laboratory through screening and isolation efforts.
Frederick Mintah Appiah, Dr. P Srinivasan, Dr. M Rajalaksmi Srinivasan et al.· Journal of Climate Innovatio...· 0 citations
Petroleum is a global primary raw material and energy resource. Despite its high economic value and energy density, its usage and extraction cause significant environmental pollution and climate change. Biosurfactants, primarily produced by microorganisms, facilitate the degradation of petroleum hydrocarbons by improving their bioavailability and solubility in the environment. Hence, they are considered as eco-friendly and biodegradable substitutes for bioremediation applications. In the current study, five novel bacterial strains, Rhodococcus sp. strain SARSHI1, Pseudomonas sp. strain SARSHI2, Pseudomonas sp. strain SARSHI3, Acinetobacter sp. strain SARSHI4, and Rhodococcus sp. strain SARSHI5, were isolated, identified, and functionally characterized to evaluate their biosurfactant-producing and hydrocarbon-degrading efficiency. The strains were systematically screened to assess their cell-surface hydrophobicity, biosurfactant activity, emulsification activity, and hydrocarbon-degrading efficiency, etc. Among all the strains, SARSHI1 governed the highest quantitative results by achieving the highest biosurfactant-producing capacity (2.54 g/L), lowest reduced-surface tension (26.87 ± 0.05 mN/m) and CMC (67 mg/L), highest adhesive bioactivity (70.6 ± 2.1%), highest emulsification index (E24 - 81 ± 0.45%), and highest hydrocarbon degradation profile (82% under glycerol supplemented condition). Media optimization analysis revealed the factors for improving the biosurfactant yield at pH 7.0, temperature (30-50 °C), 4% yeast extract, and 4% crude oil concentration. The molecular and taxonomical assessment was conducted by 16S rRNA sequencing, with partial sequences submitted to the GenBank database with unique accession numbers: 'PV034287', 'OP597529', 'OP584476', 'OQ711779', and 'OQ711775' for SARSHI1-SARSHI5, respectively. Lastly, the secondary structure of the 16S rRNA sequences was determined using the UNAFold algorithm. Therefore, the findings of this study present a robust preliminary functional framework for advanced microbial studies and highlight the potential of native bacterial strains for developing economical bioremediation applications to combating petroleum pollution.
S. Zaman, Anushka Bhrdwaj, Anuraj Nayarisseri et al.· Scientific Reports· 0 citations
This research examined the physico-chemical characteristics and cultivable bacterial diversity of a marine water samples collected from Chombala of kerala and also assessing the potential for biosurfactant production. The physical parameters indicated (Alkalinity (total), NH₃/NH₄⁺, Ca²⁺, Cl⁻, Dissolved oxygen, Electrical conductivity, Mg²⁺, NO₃⁻, NO₂⁻, pH, PO₄³⁻, Salinity, SiO2, Temperature, TDS, Total hardness & Turbidity. A total of fifteen bacterial strains were isolated, characterized morphologically, biochemically and identified as Bacillus sp. (40%), along with Vibrio sp., Pseudomonas aeruginosa, Halomonas sp., Serratia marcescens, among others. The biosurfactant screening methods employed (Including Drop Collapse, Oil Spread, Atomized Oil Spray, Microplate Assay, Tilting Slide & Emulsification (24h), Hemolytic Assay, CTAB-MB Plate, Hydrocarbon Overlay and Aggregation) revealed that 10 strains (67%) tested positive, predominantly consisting of Bacillus and Pseudomonas species. The oligotrophic and saline environment supported a diverse community of halotolerant bacteria with significant biosurfactant production potential, underscoring implications for bioremediation and aquaculture.
P. P. Jasitha, M. Kannahi*· Journal of biodiversity and...· 0 citations
Biosurfactants are surface‐active compounds synthesized by microorganisms that serve as eco‐friendly alternatives to synthetic surfactants in industrial and environmental applications. This study compared four common screening assays—hemolysis, oil displacement (ODA), drop collapse, and emulsification index (E24)—to evaluate biosurfactant‐producing bacteria from diverse habitats. A total of 154 morphologically distinct isolates were obtained from oil‐contaminated soil, kitchen chimney soot, Himalayan alpine soil, and Southern Ocean sediments. Contaminated samples showed higher microbial loads (up to 2.64 × 10
8
CFU/g) and a greater frequency of positive strains. Hemolysis yielded the highest positives (56.4%), followed by ODA (26%), drop collapse (22.7%), and E24 (19.5%). Fifteen isolates (9.7%) were positive across all tests, with four strains (HUS20, BS108, SOE17, and KC15) exhibiting strong emulsification activity (53%–60%). 16S rRNA gene analysis identified these key producers as members of the genera
Pseudomonas
,
Cytobacillus
, and
Streptomyces
, underscoring the taxonomic diversity of efficient biosurfactant‐producing bacteria. Statistical analysis indicated a positive but statistically non‐significant correlation between microbial abundance and biosurfactant activity (
r
= 0.69,
p
= 0.31). The findings highlight ODA as a more reliable and functionally relevant primary screening tool for identifying potent biosurfactant producers from both polluted and pristine environments.
Kishore Kumar Annamalai, R. Manikkam, Manigundan Kaari et al.· Journal of Surfactants and D...· 0 citations
The results confirm the effectiveness of NMR spectroscopy as a tool for studying bioremediation mechanisms and indicate that biosurfactants may act not only as emulsifiers for oils but also as modulators of the catabolic potential of the soil microbiome.
L. Biktasheva, A. Gordeev, D. S. Ivanov et al.· Eurasian Soil Science· 0 citations
Biosurfactants are sustainable alternatives to petroleum-derived surfactants, yet their industrial application is often constrained by production costs and process efficiency. This study aimed to evaluate biosurfactant production by the psychrotolerant Antarctic bacterium Streptomyces luridus So3.2 using low-cost recycled frying oils under mild cultivation conditions and to validate the process in stirred-tank bioreactors. Cultivation conditions were optimized using response surface methodology (RSM), and the same optimized pH and carbon source concentration were subsequently applied in stirred-tank reactors at laboratory scales of 2 L and 20 L, while aeration (0, 0.5 and 0.9 vvm) and agitation speed (100, 150, and 200 rpm) were evaluated as reactor-operational variables. Filtered and centrifuged recycled frying oil yielded the highest biosurfactant performance (emulsification indices exceeding 80%, enhanced oil displacement, and surface tension values below 40 mN m−1) compared to commercial oils. Biosurfactant production was growth-associated, with detectable surface activity within the first 24 h. RSM identified optimal cultivation parameters at pH 8.0, 3% (w/v) inoculum, and 2% (w/v) oil concentration. The biosurfactant exhibited a critical micelle concentration (CMC) of 29 mg L−1 and a critical micelle dilution (CMD) of 43.2, yielding an estimated broth concentration of 1.25 g L−1. At the 2 L reactor scale, moderate aeration (0.5 vvm) combined with intermediate agitation (150 rpm) preserved high surface activity, yielding emulsification indices above 83%, oil displacement halos of 12.5 cm, and surface tension values as low as 35.5 mN m−1. This performance was also maintained during validation at 20 L. FTIR and TLC analyses indicated lipid- and peptide-associated functional groups. These findings were further complemented by HPLC, MALDI-TOF MS and genome-mining analyses (antiSMASH), revealing a complex molecular profile and multiple NRPS/NRPS-like biosynthetic gene clusters, supporting the interpretation of the recovered product as a putative lipopeptide-associated surface-active extract. Overall, this work demonstrates the feasibility of producing a biosurfactant-associated surface-active extract from recycled frying oils using S. luridus So3.2 under mild conditions.
Claudio Lamilla, David Troncoso, Daniel Martínez-Cisterna et al.· International Journal of Mol...· 0 citations