@article {46042,
	title = {Biodegradation of mixed polycyclic aromatic hydrocarbons by pure and mixed cultures of biosurfactant producing thermophilic and thermo-tolerant bacteria},
	journal = {Science of the Total Environment},
	volume = {679},
	year = {2019},
	month = {AUG},
	pages = {52-60},
	type = {Article},
	abstract = {<p>Applicability of thermophilic and thereto-tolerant microorganisms for biodegradation of polycyclic aromatic hydrocarbons (PAHs) with low water solubility is an interesting strategy for improving the biodegradation efficiency. In this study, we evaluated utility of thermophilic and thermo-tolerant bacteria isolated from Unkeshwar hot spring (India) for biodegradation of four different PAHs. Water samples were enriched in mineral salt medium (MSM) containing a mixture of four PAHs compounds (anthracene: ANT, fluorene: FLU, phenanthrenc: PHE and pyrene: PYR) at 37 degrees C and 50 degrees C. After growth based screening, four potent strains obtained which were identified as Aeribacillus pallidus (UCPS2), Bacillus axarquiensis (UCPD1), Bacillus siamensis (GHP76) and Bacillus subtilis subsp. inaquosorum (U277) based on the 16S rRNA gene sequence analysis. Degradation of mixed PAH compounds was evaluated by pure as well as mixed cultures under shake flask conditions using MSM supplemented with 200 mg/L concentration of PAHs (50 mg/L of each compound) for 15 days at 37 degrees C and 50 degrees C. A relatively higher degradation of ANT (92\% - 96\%), FLU (83\% - 86\%), PHE (16\% - 54\%) and PYR (51\% - 71\%) was achieved at 50 degrees C by Aeribacillus sp. (UCPS2) and mixed culture. Furthermore, crude oil was used as a substrate to study the degradation of same PAHs using these organisms which also revealed with similar results with the higher degradation at 50 degrees C. Interestingly, PAH-degrading strains were also positive for biosurfactant production. Biosurfactants were identified as the variants of surfactins (lipopeptide biosurfactants) based on analytical tools and phylogenetic analysis of the surfactin genes. Overall, this study has shown that hot spring microbes may have a potential for PAHs degradation and also biosurfactant production at a higher temperature, which could provide a novel perspective for removal of PAHs residues from oil contaminated sites. (C) 2019 Elsevier B.V. All rights reserved.</p>
},
	keywords = {Biodegradation, Biosurfactants, Crude oil, Mixed culture, PAHs, Thermophiles},
	issn = {0048-9697},
	doi = {10.1016/j.scitotenv.2019.04.376},
	author = {Mehetre, Gajanan T. and Dastager, Syed G. and Dharne, Mahesh S.}
}
@article {50053,
	title = {Novel biosurfactant assisted biodegradation of polystyrene by Actinomycetes and its chemical understanding},
	journal = {Polymer Degradation and Stability},
	volume = {246},
	year = {2026},
	month = {APR},
	pages = {111946},
	type = {Article},
	abstract = {<p>
	The current study highlights the effective biodegradation of polystyrene by two actinobacterial strains, Glutamicibacter sp. K-1 and Rhodococcus sp. BG-30. FT-IR, Raman spectroscopy, and GPC data showed the degradation pattern of polystyrene. Additionally, GC-MS analysis showed that strain K-1 produced a variety of degradation by-products, including alkanes, 2,4-Di-ter-butyl phenol, 2-propenoic acid, tridecyl ester, and dibutyl phthalate, while strain BG-30 produced a greater amount of alkenes, phthalic acid, and isobutyl octyl esters. GPC detected a drop in polystyrene{\textquoteright}s average molecular weight (Mn), which suggests chain scission of the polymer. Changes in polystyrene{\textquoteright}s roughness and other morphological properties were shown by AFM and FE-SEM. The effects of a conventional rhamnolipid and a novel thermostable biosurfactant fatty alkene (0.1 \% each) on the breakdown of polystyrene were examined. Strain K-1 and BG-30 resulted in increasing the degradation of polystyrene to 12 \% (w/w) and 16 \% (w/w), respectively in the presence of fatty alkene biosurfactant, there was 10 \% (w/w) and 8 \% (w/w), degradation in presence of rhamnolipid. To the best of our knowledge, degradation of polystyrene by Glutamicibacter sp. has been reported as a newly identified strain and use of a novel biosurfactant together revealed their potential in biodegradation of plastic to mitigate the plastic pollution using microbial resources.</p>
},
	keywords = {Biodegradation, Fatty alkene biosurfactant, Glutamicibacter sp., Polystyrene, Rhamnolipid, Rhodococcus sp.},
	issn = {0141-3910},
	doi = {10.1016/j.polymdegradstab.2026.111946},
	author = {Sakpal, Amrapali and Haq, Nazrul and Dasgupta, Santanu and Alanazi, Fars and Alsarra, Ibrahim A. and Alam, Mahboob and Dastager, Syed G.}
}
