Publications by authors named "Arvind M Kayastha"

Recent advancements in nanomaterials have significantly impacted various sectors, including medicine, energy, and manufacturing. Among these, organic/inorganic nanohybrids have emerged as transformative tools in the food industry. This review focuses on the innovative applications of these nanohybrids in food packaging, enzyme immobilization, and contamination detection.

View Article and Find Full Text PDF

Bioactive urease from watermelon (Citrullus lanatus) seeds was purified using acetone fractionation, anion-exchange, and size-exclusion chromatography, achieving a 121-fold increase and specific activity of 3216 U/mg. The enzyme appeared as a single band on native and SDS-PAGE, with a molecular mass of 480 ± 10 kDa and subunit mass of 80 ± 10 kDa, indicating six identical subunits. Atomic absorption spectroscopy revealed 1.

View Article and Find Full Text PDF

Urea contamination in milk poses significant health risks, including kidney failure, urinary tract obstruction, fluid loss, shock, and gastrointestinal bleeding. This highlights the need for sensitive, rapid, and reliable methods to detect traces amount of urea in milk. In this study, we designed an electrochemical transducer for urea detection by utilizing purified watermelon urease (Urs), gold nanoparticles (AuNPs), and graphene oxide (GO).

View Article and Find Full Text PDF

An eco-friendly hydrothermal method synthesized VS nanosheets. Several spectroscopic and microscopic approaches (TEM) were used to characterize the produced VS nanosheet microstructure. VS, Chitosan, and nanocomposite were used to immobilize watermelon (Citrullus lanatus) urease.

View Article and Find Full Text PDF

This study looked at the effects of acarbose (ACA) and quercetin (QUE) on α-amylase activity, employing QUE and ACA to measure enzyme activity. The study observed that both drugs suppressed α-amylase activity, with greater inhibition reported at higher concentrations. The use of tryptophan residues as an intrinsic fluorescence probe permitted the observation of conformational changes in α-amylase, with CD measurements utilized to explore the secondary structure in the presence of QUE and ACA.

View Article and Find Full Text PDF

The current study presents the application of molybdenum diselenide nanoflowers (MoSe-NFs) as an innovative substrate for immobilizing α-amylase by glutaraldehyde activation. This approach results in the development of a nanobiocatalyst that exhibits remarkable advantages compared to a standalone enzyme. Several physical methods, such as fluorescence microscopy, FT-IR, SEM, TEM, XRD, AFM, and Raman spectroscopy, were used to confirm that α-amylase was successfully attached to MoSe2-NFs.

View Article and Find Full Text PDF

Starch hydrolyzing α-amylase from germinated fenugreek (Trigonella foenum-graecum) has been purified 104-fold to apparent electrophoretic homogeneity with a final specific activity of 297.5 units/mg. SDS-PAGE of the final preparation revealed a single protein band of 47.

View Article and Find Full Text PDF

α-Amylase catalyses the hydrolysis of glucosidic bonds in polysaccharides such as starch, glycogen and their degradation products. In the present study, the three-dimensional structure of fenugreek () α-amylase was determined using a homology modeling-based technique. The best predicted model was deposited in PMDB server with PMDB ID PM0084364.

View Article and Find Full Text PDF

Mutant polypeptide GB1HS#124, which is known to aggregate into amyloid-like fibrils, has been utilized as a model in this study for gaining insights into the mechanism of domain-swapped aggregation through real-time monitoring. Size exclusion with UV monitoring at 280 nm and dynamic light scattering (DLS) profiles through different time points of fibrillation reveal that the dimer transitions into monomeric intermediates during the aggregation, which could further facilitate domain swapping to form amyloid fibrils. The 1D H and 2D H-C HSQC nuclear magnetic resonance (NMR) spectra profiling through different time points of fibrillation reveal that there may be some other species present along with the dimer during aggregation which contribute to different trends for the intensity of protons in the spectral peaks.

View Article and Find Full Text PDF

Drusen deposition on sub-retinal pigment epithelium is the causal factor for age-related macular degeneration for the old-aged individuals. These deposits contain hydroxyapatite-cholesterol spherules on which several proteins and lipids accumulate to cover the retina and choroid, causing blurred vision and blindness. Amyloid-β, the known culprit in Alzheimer's disease, is one among the few major proteins known to occur in these deposits.

View Article and Find Full Text PDF
Article Synopsis
  • Puccinia triticina is a major fungal threat to wheat crops, significantly impacting yields each year.
  • The study identifies three Dicer-like genes in the P. triticina genome and shows their increased expression during germination, highlighting their role in gene regulation.
  • This research reveals a potential Dicer-dependent RNA interference pathway in P. triticina, offering valuable insights for future studies on managing wheat leaf rust disease.
View Article and Find Full Text PDF

Hydroxyapatite deposition and calcification occurs over cholesterol-containing lipid droplets between Bruch's membrane and sub-retinal pigment epithelium (sub - RPE) in the eyes of patients affected by age-related macular degeneration (AMD) as spherules, nodules, and Bruch's membrane plaques. In the present study, an attempt has been made to prepare a composite containing hydroxyapatite and cholesterol to elucidate interactions involved in the formation of such organic-inorganic interphase. To understand the mechanism of hydroxyapatite deposition on cholesterol, we have applied various biophysical techniques such as dynamic light scattering (DLS) measurements, transmission electron microscopy (TEM) imaging, Fourier transform infrared (FTIR) spectroscopy and solid-state nuclear magnetic resonance (ssNMR) spectroscopy on the prepared composite.

View Article and Find Full Text PDF

Present work describes the purification of an acidic β-galactosidase from Lens culinaris (Lsbgal) to homogeneity via 857 fold with specific activity of 87 U/mg. The molecular mass of purified Lsbgal was estimated ~ 76 kDa by Size Exclusion Chromatography on Superdex-200 (ÄKTA purifier) and on SDS-PAGE, showed hetero-dimeric subunits i.e.

View Article and Find Full Text PDF

β-Amylase was immobilized onto GQDs using 3-aminopropyltriethoxysilane and glutaraldehyde. Optimization was carried out by Box-Behnken design and binding was confirmed by SEM, AFM, FTIR and fluorescence microscopy. Predicted optimum immobilization efficiency (88.

View Article and Find Full Text PDF

Acute respiratory distress syndrome (ARDS), manifested by intricate etiology and pathophysiology, demands careful clinical surveillance due to its high mortality and imminent life support measures. NMR based metabolomics provides an approach for ARDS which culminates from a wide spectrum of illness thereby confounding early manifestation and prognosis predictors. H NMR with its manifold applications in critical disease settings can unravel the biomarker of ARDS thus holding potent implications by providing surrogate endpoints of clinical utility.

View Article and Find Full Text PDF

In the present study, Multiwalled carbon nanotubes (MWCNT) decorated with two different nanoparticles namely tungsten disulfide (WS) and tin oxide (SnO), nanocomposites (NCs) were synthesized via hydrothermal method. Spectroscopic studies showed that both synthesized NCs possess nearly same functional groups but MWCNT-SnO NCs are rich in O-functional group. Microscopic studies revealed that both NCs have different morphological microstructure.

View Article and Find Full Text PDF

In this communication, fenugreek β-amylase was immobilized onto functionalized tungsten disulfide nanoparticles through cross-linker glutaraldehyde and successful immobilization was confirmed by SEM, AFM and FTIR spectroscopy. To make the process economical and efficient, optimization of independent variables was carried out using Box-Behnken design of response surface methodology. Approximately similar predicted (85.

View Article and Find Full Text PDF

Nitrogen doped carbon quantum dots (NCQDs) were synthesized via hydrothermal route. The NCQDs are thermally and optically stable with high flouresence yield. For the synthesis of NCQDs, citric acid and urea was taken as carbon and nitrogen sources, respectively.

View Article and Find Full Text PDF

Multiwalled carbon nanotubes molybdenum disulfide 3D nanocomposite (MWCNT-MoS NC) was successfully synthesized via eco-friendly hydrothermal method. The microstructural characterization of synthesized nanocomposite was carried out using different spectroscopic and microscopic techniques. Nanocomposite was activated using glutaraldehyde chemistry and used as a platform to immobilize Lens culinaris β-galactosidase (Lsbgal) which resulted in 93% of immobilization efficiency.

View Article and Find Full Text PDF

β-Amylase has been de novo synthesized from germinating fenugreek seeds. Enzyme has been isolated and purified from 36 h germinated seeds with 226-fold purification and specific activity of 763 U/mg. Homogeneity of the purified β-amylase has been confirmed with size-exclusion chromatography, SDS-PAGE and MALDI MS/MS analysis.

View Article and Find Full Text PDF

Cross-kingdom RNAi is a well-documented phenomenon where sRNAs generated by host and pathogens may govern resistance or susceptible phenotypes during host-pathogen interaction. With the first example of the direct involvement of fungal generated sRNAs in virulence of plant pathogenic fungi Botrytis cinerea and recently from Puccinia striiformis f. sp.

View Article and Find Full Text PDF

The present work describes efficient hydrolysis of native starch by a novel β-amylase from peanut (Arachis hypogaea). The Dextrose Equivalent value, which is a measure of starch hydrolysis, for potato and corn starch increased significantly by 40% and 10%, respectively, releasing maltose. Scanning electron microscopy revealed that enzymatic corrosion occurred mainly at the surface of starch granules, leaving broken granules to smaller particles at later stage of digestion.

View Article and Find Full Text PDF

β-Amylase from un-germinated seeds of peanut (Arachis hypogaea) was purified to apparent electrophoretic homogeneity with final purification fold of 205 and specific activity of 361μmol/min/mg protein. The enzyme was purified employing simple purification techniques for biochemical characterization. The purified enzyme was identified as β-amylase with M of 31kDa.

View Article and Find Full Text PDF