Indian Journal of Microbiology最新文献

Huperzine A (HupA) and huperzine B (HupB) are potent acetylcholinesterase inhibitor used widely for clinical treatment of Alzheimer’s disease, which are mainly extracrted from natural populations of Huperzia species. This study aimed to the evaluate potential of producing Hup of native Huperzia javanica species collected in Vietnam as well as identify endophytic fungi that produce high Hup or simultaneously produce many types of Hup derived from this plant as a material source for natural Hup production. By HPLC–DAD-MS analysis, H. javanica collected from Ha Giang, Vietnam was found as a novel producer of HupA and HupB with a yield of 0.513 mg/g dry weight (wt) and 0.192 mg/g dry wt, respectively. Inspired by this discovery, a total of 63 endophytic fungi were isolated from healthy tissues of the collected H. javanica plants, including 52 fungal strains belonging to nine genera and 11 unidentified strains based on morphological characteristics. Using HPLC, 9 Hup-producing fungi were identified when compared to the standard HupA and HupB. Surprisingly, 7 fungal strains produced both HupA and HupB, among which strain TLC12 produced the highest HupA and HupB contents of 0.271 and 0.163 mg/g mycelium dry cell weight (gdcw), respectively. Fungal strains TLC19 and TLC22 only yielded a respective amount of 0.305 and 0.135 mg/ gdcw of HupA. Combining with Internal Transcribed Spacer sequence analysis, 9 potent fungi were identified as Neurospora calospora (TLC9, TLC10, TLC11), Schizophyllum commune TLC12, Epicoccum sorghinum TLC13, Alternaria tenuissima TLC14, Cephalotrichum sp. TLC20, Daldinia sp. TLC19, and Schizophyllum sp. TLC22. To the best of our knowledge, this is the first report demonstrating H. javanica as a prolific and novel source of endophytic fungi capable of yielding high HupA and HupB contents. The exploitation of 9 Hup-producing fungi is also valuable for both basic research and industrial Hup manufactures. These findings open new perspectives for industrial production of fungal HupA and HupB and conservation of Huperzia species.

This work describes the chronoamperometry deposition of Chitosan/silver nanocomposite and applied as platform for the development of immunoassay for the detection of Pseudomonas aeruginosa. The film was characterized by UV (Ultra visible spectroscopy), FTIR (Fourier transform infra red), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDAX) and electrochemical detection methods. The electrochemical detection of Pseudomonas aeruginosa was done based on the Anti Ps tagged with silver nanoparticles decorated graphene oxide sheets which in turn binds to the antigen and the response was observed using Hydrogen peroxide (H₂O₂) in PB (Phosphate Buffer) electrolyte. From the results, the sensitivity range is from 10¹ to 10⁷ CFU/mL and LOD is calculated as 9.36 CFU/ml. The developed immunosensor also have high stability, reproducibility and reusability.

Rheumatoid arthritis (RA) is an autoimmune disorder that induces joint inflammation, cartilage injury, and bone damage. Thus far, methotrexate (MTX) is a primary DMARD drug to treat RA. Despite high efficiency, its clinical application is compromised due to delivery-associated systemic side effects. This investigation reports a Quality-by-design (QbD; Box Behnken Strategy) assisted production of a novel, innovative, and multipurpose polycation-templated approach for producing stable albumin MTX nanoparticles (pT-AMTX-NP). This approach formed a highly biocompatible MTX formulation with reduced toxicity (1.81 ± 0.54% hemolysis) compared to plain MTX (13.19 ± 2.77%; SEM:1.965). pT-AMTX-NP was found to be nanometric (Particle size: 135.86 ± 5.17 nm; PDI: 0.27) with a net surface charge of ζ –10.15 ± 2.19 mV. With 4.01-fold cationization (TNBS assay), pT-AMTX-NP showed high drug loading (64.98 ± 1.25%) and sustained MTX release under physiological conditions (up to 48 h; p < 0.001). The nanoformulation followed the Higuchi release kinetics model (R², 0.9957). Significantly reduced burst release by 70.61% (p = 0.0002) and 12.89% (p = 0.0115) compared to plain MTX and conventional MTX-formulation (AMTX-NP), respectively. Interestingly, pT-AMTX-NP showed pH-responsive drug release bio-environment-responsive architectural change. Cell line studies in lipopolysaccharide (LPS) stimulated RAW264.7 macrophage showed a significant reduction in intracellular nitrite level following pT-AMTX-NP treatment (p < 0.01). Cellular uptake and cell viability confirmed selective cellular uptake potential in inflamed cells. Furthermore, compared to the control, the high intracellular ROS-generation was noted with pT-AMTX-NP (2.1485-fold; p < 0.01). Furthermore, hemolysis assay and stability assessments were also conducted to determine the hemocompatibility and suitable conditions for the storage of nanoformulation. The outcome of this study suggests that the developed multipurpose nanoformulation is a superior therapeutics approach for improved RA treatment. Suggestively, the developed strategy can also be adopted to benefit other clinical situations that demand to counter inflammation, cytostatic as well as psoriatic conditions.

A total of 30 native Trichoderma isolates were collected from the Agricultural Research Station, Ummedganj- Kota, Rajasthan, India. Out of which 9 native isolates were evaluated for bio-efficacy against Sclerotium rolfsii. Isolate ARS K-21 exhibited maximum inhibition (89.26%), followed by ARS K-11 (83.70%) in dual culture. Subsequent evaluations revealed the compatibility of efficient isolate ARS K-21 with various bio botanicals displaying minimum inhibition with Vermiwash (1.11–3.70%) followed by Beejamarat (0.38–15.92%) and Brahmastra (7.78–19.68%), while ARS K-11 displayed compatibility only with Dasparni ark with a minimum inhibition of 1.11–3.70%. Assessment of abiotic stress tolerance of the isolates revealed that most isolates thrived at 200 mM and 400 mM NaCl salt concentrations, with ARS K-21 and ARS K-24 demonstrating moderate growth levels across higher concentrations, except at 1200 mM. Optimal growth of the isolates occurred at 25 and 30 °C, with deviations leading to growth inhibition. Isolates ARS K-1, ARS K-11, ARS K-12 and ARS K-21 exhibited resilience to temperature extremes. ARS K-21 has shown exceptional growth proficiency across a wide pH spectrum (pH 5 to 8.5) followed by ARS K- 24, highlighting their versatility. Mass multiplication of efficient isolate ARS K-21 enriched with vermicompost led to the standardization of a dosage (30 g/kg soil) for managing collar rot in lentil crops at 5 g inoculum per kg soil of S. rolfsii.

Nanofillers have emerged as versatile materials with immense potential in various biosensing and biotechnological applications, including tissue engineering, drug delivery, gene silencing, and biomedical imaging. This review explores the diverse types of nanofillers utilized in biosensors and biotechnological systems, their synthesis methods, classification, and their impact on enhancing the performance and functionality of biotechnological applications. The review delves into the intricate role of nanofillers in biosensors, investigating their influence on sensitivity, selectivity, and overall performance. It highlights their contributions to advancing diagnostic capabilities, biomarker detection, and real-time monitoring. Additionally, the review explores the integration of nanofillers in novel biosensing platforms, shedding light on their potential to revolutionize point-of-care diagnostics and personalized medicine. Further, discusses the challenges associated with nanofillers, such as toxicity and biocompatibility concerns, and provides insights into future directions and emerging trends in this rapidly evolving field. By comprehensively examining the synthesis, characterization, and performance enhancement strategies of nanofillers in multifarious biological applications. This review article aims to inspire further research and innovation for the development of advanced biotechnological systems.

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SeqCode is a nomenclatural code for naming prokaryotes based on genetic information. With the majority of prokaryotes being inaccessible as pure cultures, they are not eligible for naming under the International Code of Nomenclature of Prokaryotes. To address this challenge, a new concept that is SeqCode, which assign names to prokaryotes on the basis of genome sequence, has been announced in 2022. The valid publication of names for prokaryotes based on isolated genome, metagenome-assembled genomes, or single-amplified genome sequences. It operates through a registration portal, SeqCode Registry, where metadata is linked to names and nomenclatural types. This code provides a framework for reproducible nomenclature for all prokaryotes, either culturable or not and facilitates communication across all microbiological disciplines. Additionally, the SeqCode includes provisions for updating and revising names as new data becomes available. By providing a standardized system for naming and classifying these microorganisms based on their genetic information, the SeqCode will facilitate the discovery, understanding and comparison of these microorganisms, helping us to understand their role in the environment and how they contribute to the functioning of the Earth.

Due to human progress in various areas, the demand for oil and its products has increased. This leads to an increase in environmental contamination and serious problems worldwide. A wide range of microorganisms produce biosurfactants which have the ability to degrade oil. The aim of this study was to isolate biosurfactant-producing bacteria from wastewater contaminated with oil and oil sludge in Asemari and Bangestan, Iran. To evaluate biosurfactant activity, bacterial strains were isolated from samples and characterized by assays including hemolytic activity, oil spreading, emulsification activity, and surface tension. The isolates with the highest biosurfactant production activity were identified by morphological, biochemical, and molecular methods. The samples yielded 23 isolates, of which 15 had hemolytic properties. Among them three isolates with the highest biosurfactant activity were selected based on oil spreading test, emulsification activity, and surface tension. The isolates were identified as Pseudomonas mendocina, Pseudomonas alcaliphila, and Planococcus halotolerans. The oil degradation of the isolates was assessed. The breakdown of long chain hydrocarbons in oil-containing culture medium was caused by all three isolates, as revealed by GC chromatography. The present findings indicate that certain microorganisms present in oil-contaminated regions are capable of producing biosurfactants. Further research is needed to isolate and identify strains with the highest ability to produce biosurfactants for industrial purposes.

Antimicrobial resistance (AMR) poses a foremost threat to global health, necessitating innovative strategies for discovering antimicrobial agents. This review explores the role and recent advances of in-silico techniques in identifying novel antimicrobial agents and combating AMR giving few briefings of recent case studies of AMR. In-silico techniques, such as homology modeling, virtual screening, molecular docking, pharmacophore modeling, molecular dynamics simulation, density functional theory, integrated machine learning, and artificial intelligence, are systematically reviewed for their utility in discovering antimicrobial agents. These computational methods enable the rapid screening of large compound libraries, prediction of drug-target interactions, and optimization of drug candidates. The review discusses integrating in-silico approaches with traditional experimental methods and highlights their potential to accelerate the discovery of new antimicrobial agents. Furthermore, it emphasizes the significance of interdisciplinary collaboration and data-sharing initiatives in advancing antimicrobial research. Through a comprehensive discussion of the latest developments in in-silico techniques, this review provides valuable insights into the future of antimicrobial research and the fight against AMR.

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Extracellular polymeric substances (EPS) are complex, hydrated matrices produced by biofilm-forming bacteria to anchor themselves to surfaces and resist antibiotic treatment. EPS plays a critical role in the formation, maintenance and virulence of biofilms, leading to persistent infections and posing significant challenges in healthcare. Characterizing bacterial EPS is essential to understand their biochemical composition and functional properties, which is critical for optimizing their applications in biotechnology, medicine, and environmental management. Therefore, the present study aimed to isolate and screen the bacteria from Arabian Sea for their ability to produce EPS from biofilm surfaces. Additionally, the detailed characterization of the EPS was also carried out. These bacteria were identified using 16S rRNA gene sequence analysis and revealed that all the EPS-producing bacterial isolates belong to different bacterial genera (Oceanimonas, Psychrobacter and Vibrio). The bacteria were cultured on Zobell marine broth media and EPS were isolated using the propanol precipitation method. The EPS weight varied among the bacterial isolates and ranged from 0.81 g L⁻¹ to 2.21 g L⁻¹. The EPS produced by the bacterial strains have shown antimicrobial as well as free radicals (2,2-diphenyl-1-picrylhydrazyl; DPPH) and 2, 2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity. The antimicrobial and free radical scavenging properties of EPS have promising biotechnological applications in developing new antibiotics, enhancing food preservation, creating protective coatings, and improving wound healing therapies. The Fourier-transform infrared spectroscopy (FTIR) revealed the presence of aliphatic methyl, halide groups, saccharides and primary amines. Gas chromatography equipped with mass spectroscopy (GC–MS) confirmed the presence of monosaccharides such as glucose, galactose, arabinose and mannose. The EPS were further characterized using X-Ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The study highlights the importance of EPS in biofilm formation, antibiotic resistance and persistent infections, emphasizing the importance of isolating and characterizing of EPS for its potential biotechnological applications, including antimicrobial and free radical scavenging activities.

The effectiveness of probiotics for health depends on the strain type and dosage. In this study, we endeavored to establish a robust quantitative Real-time PCR method for the evaluation probiotic strains in Iranian probiotic dairy products. The process was initiated by extracting DNA from selected bacterial strains and selecting well-matched primers. Then, we optimized the Real-time PCR method to efficiently identify and quantify three prevalent beneficial bacterial strains, including Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium animalis subsp. lactis in four types of Iranian probiotic yogurt with different brands simultaneously and within 4 h. To overcome complications such as sample variability or interference with other common microorganisms in dairy products, we simultaneously used IPC and specific primers of each strain. The sensitivity and specificity obtained in the present study were 10⁶ CFU/mL for the targeted bacterial strains. The relative standard deviation (%RSD) was maintained at less than 2% regarding repeatability and reproducibility. The method designed and validated for identifying and counting these strains exhibits remarkable specificity, sensitivity, accuracy, optimal reaction efficiency, and minimal variance. Collectively, our method has proven to be specialized, cost-effective, and rapid, which makes it suitable for qualitative evaluation of probiotic dairy products in the industry.

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