2026· International journal of research and innovation in applied science· Vol 11, pp. 1700-1708· 0 citations
TL;DR
The thermostability and activity profiles of these enzymes suggest suitability for applications that demand resilience to heat and harsh chemical conditions, including biofuel generation, high-temperature food processing, pharmaceutical enzyme formulations and bioremediation of thermally stressed or contaminated environments.
Abstract
Thermophilic environments such as hot springs are invaluable natural reservoirs of extremophilic microorganisms that produce thermostable enzymes with significant industrial utility. This study explored the thermophilic microbial community of the Madkot geothermal hotspot (Pithoragarh), Uttarakhand. Samples collected from high-temperature niches were subjected to enrichment and isolation under thermophilic conditions, followed by comprehensive biochemical profiling including indole, methyl red, Voges–Proskauer, phosphate solubilization, catalase, oxidase, urease and nitrate reduction tests to elucidate metabolic capabilities relevant to industrial processes. Selected thermophilic strains were molecularly identified by 16S rRNA gene sequencing and affiliated with the genera Bacillus and Pseudomonas. Both taxa demonstrated the capacity to produce industrially relevant enzymes under elevated temperature regimes: a Bacillus sp. isolate exhibited protease activity with a maximum specific activity of 23.05 U/ml, while a Pseudomonas sp. isolate synthesized amylase with a peak specific activity of 31.02 U/ml. The thermostability and activity profiles of these enzymes suggest suitability for applications that demand resilience to heat and harsh chemical conditions, including biofuel generation, high-temperature food processing, pharmaceutical enzyme formulations and bioremediation of thermally stressed or contaminated environments. Overall, the results underscore the rich, yet underexplored, thermophilic microbial diversity of Uttarakhand hot springs and emphasize their importance as a source of sustainable, heat-tolerant biocatalysts for industrial biotechnology. Future work will focus on enzyme purification, detailed thermostability profiling and cost effective pilot-scale production in relevant process conditions.
Lipases obtained from thermophilic microorganisms are attracting great interest in the industrial field due to their stability under high-temperature conditions and their wide range of industrial applications. In this study, thermophilic bacterial strains were isolated from water and mud samples collected from Erzurum Ilica Hot Springs (Turkey). An isolate producing a potent extracellular lipase was selected, named IO3, and identified by 16S rRNA sequencing. Sequencing analysis revealed that this isolate showed 99% similarity to Aeribacillus pallidus. The lipase enzyme purified from the isolate was obtained using two comparative strategies. The conventional multi-stage chromatographic approach, which includes ammonium sulfate precipitation, ion exchange chromatography, and gel filtration chromatography, provided 9.3-fold purification with a 3.18% recovery. However, the alternative Three-Phase Partitioning (TPP) system provided rapid, single-step recovery with a significantly higher yield of 38.79%, although the purification fold remained 0.65 under the tested conditions. The molecular weight of the purified A. pallidus IO3 lipase was determined to be approximately 33.88 kDa by SDS-PAGE. The enzyme showed optimum activity at pH 8.0 and 50 °C and maintained considerable thermal stability; the enzyme retained significant activity levels (45-69%) even at high temperatures such as 70 °C and 80 °C after an incubation period of 120 minutes. Among the tested metal ions, Fe2+, Fe³+, Cu2+, and Zn2+ enhanced enzyme activity, while the enzyme showed stability in the presence of Li+ and Cu2+ ions. Lipase activity also increased in the presence of surfactants, while chloroform enhanced enzyme activity by 22-338% depending on solvent concentration. The enzyme showed the highest activity toward p-nitrophenyl palmitate. The enzyme was completely inhibited by DTNB, IAA, and EDTA. In addition, the enzyme retained low activity in the presence of β-mercaptoethanol. The Km and Vmax values were calculated as 0.46 mM and 51.44 µmol·min-1·mg-1, respectively, using nonlinear regression analysis. Overall, these findings indicate that A. pallidus IO3 lipase is a thermostable and chemically tolerant enzyme with potential applicability in industrial biocatalysis and detergent-related processes.
Ikra Ozkan, A. Adiguzel· Preparative Biochemistry & B...· 0 citations
Thermostable protease enzymes can be produced by thermophilic bacteria that act as biocatalysts in protein hydrolysis and have extensive industrial applications. The supply of stable and high-performance protease enzymes is still insufficient, encouraging exploration of thermophilic bacteria from extreme environments as potential producers. The aim of this study was to identify and characterize the macroscopic, microscopic, physiological, and biochemical features of thermophilic bacterial isolates that indicated protease production. This study was conducted using descriptive methods through rejuvenation, screening, and characterization of thermophilic bacteria isolated from the Sapan Hot Spring, South Solok Regency, as potential thermostable protease producers. Based on the results, six protease-producing thermophilic bacterial isolates, namely TUA-01, TUA-02, TUA-11, TUA-21, TUA-26, and TUA-31, with the highest Proteolytic Index (PI) value being isolate TUA-26. Characterization of the six protease-producing thermophilic bacterial isolates revealed differences in colony morphology characteristics, Gram-positive, rod-shaped cells, subterminal spores, motility, and catalase-positive. The thermophilic bacterial isolate TUA-26 has the potential to produce thermostable protease enzymes at high temperatures, making it highly promising for use in various biotechnology and industrial applications.
Mufidhatul Muqarramah, A. Agustien, Feskaharny Alamsjah· Biospecies· 0 citations
Various isolates exhibited cellulase, xylanase, and esterase activities on untreated rice and wheat straw, demonstrating the capacity to deconstruct lignocellulosic biomass without prior pretreatment, and Enzymatic activities and fermentation profiles varied substantially among strains.
Sai Suresh Hivarkar, P. Dhakephalkar, S. Dagar· World Journal of Microbiolog...· 0 citations
Till to date, there is no report on isolation of microorganisms from the Mahiwal hot water spring in Balochistan, Pakistan. In the current manuscript, we report on isolation and morphological, biochemical and molecular characterization of a thermophilic microorganism from this hot water spring. The isolated bacterial strain, MAS2, is rod shaped with 1 µm width and 5 µm length. It forms cream-colored slimy colonies. The strain has the ability to grow in the presence of air between 40 and 75 °C with an optimum growth temperature and pH of 65 °C and 6.5, respectively. It can utilize various sugars, hydrocarbons and carboxylic acids as sole carbon source. No additional salt is required for its growth, though relatively higher yield was achieved with the addition of 0.5% NaCl. The strain MAS2 is capable of producing several important extracellular enzymes of industrial use including an amylase, a lipase, an oxidase and a protease. The 16S rRNA gene sequence of strain MAS2 exhibited high homology with various species belonging to genus Geobacillus. The highest homology of 98.66% was observed with Geobacillus kaustophilus. However, the biochemical characteristics of the strain were more similar to Geobacillus thermopakistaniensis and Geobacillus uzenensis. These results indicate that strain MAS2 represents an unidentified species belonging to genus Geobacillus.
Keywords: Thermophiles; 16S rRNA sequence: Geobacillus sp. MAS2; biochemical characterization; extracellular enzymes.
N. Taj, M. A. Siddiqui, Osama Ahmed Siddiqui et al.· The Journal of Animal and Pl...· 0 citations
The development of robust enzyme systems and the use of low-cost feedstocks for lignocellulosic biomass deconstruction remain major challenges for biorefineries. Here, we report a strategy to discover and produce thermostable hemicellulolytic enzymes from industrial microbiomes enriched on spent mushroom substrate (SMS) at 70 °C. A thermophilic bacterium representing a putative novel species, Parageobacillus sp. DSM 35475, was isolated and cultivated on a medium composed exclusively of SMS and digestate, demonstrating the feasibility of producing extracellular enzymes from agro-industrial residues. The resulting cell-free secretome exhibited xylanase activity of 0.22 U/mL, with an optimum at 80 °C and pH 7, while retaining more than 30% of its maximal activity between 60 and 90 °C and more than 50% activity after prolonged incubation at 75-80 °C. More than 40% of the initial activity was preserved after 80 days of storage at 4 °C. HPAEC-PAD analysis of hydrolysis products, together with zymographic and genomic analyses, indicated the presence of a multifunctional hemicellulolytic system comprising endo-xylanase, β-xylosidase, α-L-arabinofuranosidase, and endo-mannanase activities. The secretome hydrolysed beechwood xylan, arabinoxylan and alkali-pretreated SMS, releasing mixtures of mono- and oligosaccharides under thermophilic conditions. Genome annotation predicted a diverse CAZyme repertoire and a dedicated xylan/arabinan utilisation locus consistent with the observed biochemical phenotype. Overall, this study demonstrates the feasibility of producing a thermostable hemicellulolytic secretome from low-cost agro-industrial residues and identifies Parageobacillus sp. DSM 35475 as a promising source of thermophilic enzymes for future lignocellulose bioconversion.
Luca Bombardi, Valerio Sabellico, Luca Zuliani et al.· International Journal of Bio...· 0 citations
ABSTRACT Polyethylene terephthalate (PET) waste represents a major environmental challenge due to limited recycling solutions. Thermophilic bacteria from geothermal environments harbor diverse enzymatic machinery adapted to extreme conditions, offering promising biocatalysts for plastic degradation; however, biological resources from Peru and other South American countries remain scarce. We characterized four bacterial strains isolated from two geothermal sites in Cajamarca, Peru, screened for PET hydrolysis at 50°C. Whole‐genome sequencing using hybrid assembly achieved near‐complete circular genomes. GTDB‐Tk classification identified three species: Neobacillus thermocopriae (strain 19A), Bacillus licheniformis (strains 16P and BI2), and Brevibacillus agri (strain BI8). Quantitative assays revealed that strain 16P achieved the highest mass loss (0.598%), followed by strain BI8 (0.449%). ATR‐FTIR analysis of the incubated sheets showed a significant reduction of the ester carbonyl index in strains 16P, 19A, and BI8 relative to both non‐incubated PET and an abiotic control, whereas strain BI2 did not differ from the controls, indicating preferential modification of ester bonds at the sheet surface. Genome mining and structure‐based homology searches identified multiple candidate enzymes similar to validated PETases and carboxylesterases, including PETase46‐like homologs in strains BI8 and 16P and a terephthalate‐active carboxylesterase homolog in strain 16P. Molecular docking supported the conservation of catalytic geometry and substrate‐binding sites in these candidates. This work represents one of the first systematic genomic and structural characterizations of putative PET‐hydrolases in Peruvian geothermal bacteria, expanding knowledge of extremophile diversity and advancing thermostable enzymes for sustainable plastic waste management.
Marco A Rivera-Jacinto, Claudia Rodríguez-Ulloa, Sara R Briones-Ramírez et al.· MicrobiologyOpen· 0 citations