No abstract

An electrochemical biosensor was fabricated using nanoparticles of acetylcholinesterase (AChE) and choline oxidase (ChO)/Pt nanoparticles (PtNPs)/porous graphene oxide nanosheet (GONS) composite. A pencil graphite electrode (PGE) was used for the electrodeposition of nanocomposite and the determination of acetylcholine (ACh), a neurotransmitter. Various techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectra and cyclic voltammetry (CV) were used for characterization. This biosensor (AChENPs-ChONPs/GONS/PtNPs/PGE) indicated a very short response time (3 s), a lower limit of detection (0.001 µM), good linearity (0.001–200 µM), longer storage stability (6 months) and better reproducibility. The percent analytical recoveries of added acetylcholine in serum (5.0 and 10 µM) were found to be 97.6 ± 0.7 and 96.5 ± 0.3 for the present biosensor. The coefficients of variation were obtained to be 8% and 3.25%, correspondingly. The biosensor was applied to measure the ACh amount in the serum of healthy individuals and patients with Alzheimer’s disease. The number of interferents had no effect on the biosensor at their physiological concentrations.

Mung bean (Vigna radiata L.) sprout is a popular fresh vegetable, tasty and high in antioxidants. To increase yield and quality after the occurrence of both abiotic and biotic stresses, the application of seaweed extracts is of great importance. Hence, this study was conducted to determine the effect of Ascophyllum nodosum extract (ANE) in the presence of salt on the antioxidant potential of V. radiata sprouts. Different concentrations of ANE viz. 0.00, 0.01, 0.05, 0.10, and 0.50% and NaCl 0, 25, 50, 75, and 100 mM alone and in combinations were tested for researching the antioxidant potential of V. radiata sprouts at 0, 24, and 36 h of sprouting. The DPPH free-radical-scavenging activity of sprouts of V. radiata was found to increase with time and peaked at 24 h of treatment. The A. nodosum extract (0.01%) could reverse the ill effect of the low level of salinity posed by up to 25 mM NaCl. The increasing salinity deteriorated the antioxidant activity using ABTS method of sprouts down to 20.45% of the control at 100 mM NaCl. The total phenolic content (TPC), total flavonoid content (TFC), and reducing power of V. radiata sprouts was found to increase till 36 h of sprouting. A slight increase in TPC, TFC and reducing power was observed when seeds were treated with low concentrations of ANE. The elevation in TPC, TFC and reducing power upon treatment with low concentrations of ANE was also noticed in sprouts in saline combinations. Alpha amylase inhibition activity was found to reach a (67.16% ± 0.9) maximum at 24 h of sprouting at a 0.01% concentration of ANE. Tyrosinase inhibition and alpha glucosidase inhibition was 88.0% ± 2.11 and 84.92% ± 1.2 at 36 h of sprouting, respectively, at 0.01% concentration of ANE. A. nodosum extract is natural, environmentally friendly, and safe, and could be used as one of the strategies to decline stress at a low level and enhance the antioxidant activities in V. radiata sprouts, thus increasing its potential to be developed as an antioxidant-based functional food.

No abstract

No abstract