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51.
Ajay C. Lagashetti Sanjay K. Singh Laurent Dufoss Pratibha Srivastava Paras N. Singh 《Molecules (Basel, Switzerland)》2022,27(2)
Filamentous fungi synthesize natural products as an ecological function. In this study, an interesting indigenous fungus producing orange pigment exogenously was investigated in detail as it possesses additional attributes along with colouring properties. An interesting fungus was isolated from a dicot plant, Maytenus rothiana. After a detailed study, the fungal isolate turned out to be a species of Gonatophragmium belonging to the family Acrospermaceae. Based on the morphological, cultural, and sequence-based phylogenetic analysis, the identity of this fungus was confirmed as Gonatophragmium triuniae. Although this fungus grows moderately, it produces good amounts of pigment on an agar medium. The fermented crude extract isolated from G. triuniae has shown antioxidant activity with an IC50 value of 0.99 mg/mL and antibacterial activity against Gram-positive bacteria (with MIC of 3.91 μg/mL against Bacillus subtilis, and 15.6 μg/mL and 31.25 μg/mL for Staphylococcus aureus and Micrococcus luteus, respectively). Dyeing of cotton fabric mordanted with FeSO4 using crude pigment was found to be satisfactory based on visual observation, suggesting its possible use in the textile industry. The orange pigment was purified from the crude extract by preparative HP-TLC. In addition, UV-Vis, FTIR, HRMS and NMR (1H NMR, 13C NMR), COSY, and DEPT analyses revealed the orange pigment to be “1,2-dimethoxy-3H-phenoxazin-3-one” (C14H11NO4, m/z 257). To our understanding, the present study is the first comprehensive report on Gonatophragmium triuniae as a potential pigment producer, reporting “1,2-dimethoxy-3H-phenoxazin-3-one” as the main pigment from the crude hexane extract. Moreover, this is the first study reporting antioxidant, antibacterial, and dyeing potential of crude extract of G. triuniae, suggesting possible potential applications of pigments and other bioactive secondary metabolites of the G. triuniae in textile and pharmaceutical industry. 相似文献
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Arya Ghosh Subash C.B. Gopinath Sayeed Mohammad Firdous Santheraleka Ramanathan 《印度化学会志》2022,99(8):100604
Human Mammary Tumor Virus (HMTV) or Mouse Mammary Tumor Virus holds similarity as an endogenous onco-retrovirus belongs to retroviridae family, predominantly infects the epithelial cell of human as well as mouse. With the recognition of nano-biosensor in nanotechnology, ideal interdigitated electrode (IDE) was genuinely performed for HMTV detection. Aluminium enriched IDE (AlIDE) was fabricated for high performance detection with a cost-effective photolithography technique. In this research, (3-glycidyloxypropyl) trimethoxysilane refined platform was selected to detect the conductivity with HMTV target DNA interaction on the designed AlIDE. Strong binding affinity of streptavidin-biotin with target DNA enhanced the sensitivity by empowering higher number of HMTV probe and target complementation on sensing surface. Furthermore, the target DNA was immobilized on probe modified AlIDE and a quantitative value of 100 aM attained as a lowest detection. A linear with dose-dependent duplex formation was shown with the regression coefficient value of 0.964. Negative control has shown insignificant detection at 10 pM, which justifies the higher fold discrimination with specificity. The excellence of AlIDE performance in detection of HMTV may pave the way for more verification on other diseases. 相似文献
54.
Jyoti S. Gokhale Moreshwar P. Hude Ganapati D. Yadav Morgan Thomas Janusz Kozinski Ajay K. Dalai 《印度化学会志》2022,99(9):100647
An ongoing major outbreak of mountain pine beetle in Western Canada has provided a clear opportunity to utilize waste pinewood as a source of renewable energy. Therefore hydrothermal processing of waste pinewood as a feedstock for bio-oil and biochar production using subcritical and supercritical water technology was carried out in semi-batch mode to investigate the effect of pressure (200–400 bar) and temperature (300–400 °C) on the yield and composition of bio-oil. The pinewood samples have very high cellulose and hemicellulose content but low ash content and are thus a formidable feedstock for bioenergy production. The optimum conditions for the hydrothermal processing of the pinewood in a tubular reactor were found to be 400 °C and 250 bars with respect to biochar and bio-oil yield based on the highest calorific value analysis. Detailed characterization of bio-oil and biochar was performed using GCMS, NMR, SEM, calorific value, and elemental analysis, respectively. The critical components of bio-oil were found to be phenols, methoxyphenols, hydroxymethyl furfural (HMF), and vanillin, whereas as compared to the raw pine wood, the biochar was considerably lower H:C and O:C ratios than those of the unprocessed pinewood. The analyses of bio-oil by means of GCMS and 1H NMR showed that it was mainly composed of heterocyclic compounds, phenols, aldehydes and acids. 相似文献
55.
Nor Azizah Uda Hashim Subash C. B. Gopinath Sharipah Nadzirah 《Mikrochimica acta》2016,183(12):3119-3126
The authors introduce a method for spatially arranged DNA immobilization on 10-nm gold nanoparticles (GNP) deposited on a silicon substrate carrying nanogapped interdigitated electrodes. The GNPs are covalently bound to the surface via silane chemistry, and the single steps of fabrication are monitored by FTIR spectroscopy and atomic force microscopy. This GNP deposition technique is shown to reduce the size of the nanogaps to 130 nm. FTIR also was used to monitor the immobilization of DNA on the surface of the interdigitated electrodes. This method allows DNA to be immobilized in a uniform and homogenous way. The utility of the method is demonstrated by immobilizing probe DNA on the surface and detecting target DNA specific for the human papilloma virus via fluorescence with a detection limit as low as 1 pM. In our perception, this method for GNP-mediated DNA immobilization enables high-performance sensing of a wide range of target (analyte) DNA. 相似文献
56.
Microfluidic integration of substantially round glass capillaries for lateral patch clamping on chip 总被引:2,自引:0,他引:2
High-throughput screening of drug candidates for channelopathies can greatly benefit from an automated patch-clamping assay. Automation of the patch clamping through microfluidics ideally requires on-chip integration of glass capillaries with substantially round cross section. Such round capillaries, if they can only be integrated to connect isolated reservoirs on a substrate surface, will lead to a "lateral" configuration which is simple yet powerful for the patch clamping. We demonstrate here "lateral" patch clamping through microfluidic integration of substantially round glass capillaries in a novel process. The process adopts two well-known phenomena from microelectronics: keyhole-void formation and thermal-reflow of phosphosilicate glass in silicon trenches. The process relies on the same physical principle as the preparation of conventional micropipette electrodes by heat-pulling and fire-polishing glass tubes. The optimized process forms capillaries with a diameter approximately 1.5 microm and variation <10%. Functionality of the integrated glass capillaries for the patch-clamp recording has been verified by statistical test results from a sample of one hundred capillaries on mammalian cells (RBL-1) in suspension: 61% formed gigaseals (>1 GOmega) and of those approximately 48% (29% of all) achieved whole-cell recordings. Pharmacological blockade of ion channel activity and longevity of a whole-cell mode on these capillaries have also been presented. 相似文献
57.
Pramesh N. Kapoor Ajay K. Bhagi Ramesh N. Kapoor 《Journal of organometallic chemistry》1991,420(3):321-325
The first organotin(IV), aluminium(III)-μ-oxoisoprovides of the type [R3SnOA](OiPr)2] (R = Me or Ph) have been made by heating of trimethyl- or triphenyl-tin acetate with aluminium isopropoxide. The reactions of these μ-oxoisopropoxides with benzoylacetone in 1:1 and 1:2 molar ratios yielded the compounds of the type [R3SnOAl(OiPr)(bzac)] and [R3SnOAl(bzac)2] (where R = Me or Ph and BZAC = deprotonated benzoylacetone), respectively. 相似文献
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Palladium catalyzed intramolecular aminoacetoxylation of d-ribose derived alkenyl tosylsulfonamide to deliver l-deoxyallonojirimycin in an overall yield of 19%. The preliminary screening of l-deoxyallonojirimycin against carbohydrate processing enzymes showed moderate inhibitory activity against α-glucosidase (yeast) and α-mannosidases. 相似文献