V. Malapermal; J.N. Mbatha; R.M. Gengan; K. Anand
Abstract
This study was aimed at developing a simple, eco-friendly and cost effective green chemistry method for the synthesis of bimetallic Au-Ag nanoparticles using Ocimum basilicum aqueous leaf and flower extracts, respectively as the natural reducing agents. The successive reduction of chloroauric acid and ...
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This study was aimed at developing a simple, eco-friendly and cost effective green chemistry method for the synthesis of bimetallic Au-Ag nanoparticles using Ocimum basilicum aqueous leaf and flower extracts, respectively as the natural reducing agents. The successive reduction of chloroauric acid and silver nitrate led to the formation of Au-Ag nanoparticles within 10 min at room temperature, suggesting a higher reaction rate than chemical methods involved in the synthesis. Stable, spherical nanoparticles with well-defined dimensions of average size of 3-25 nm was confirmed by UV-Visible spectroscopy, TEM, SEM-EDX, DLS, and zeta potential, whilst, FTIR in combination with GC-MS analyzed the functional groups adhered to the surface of the nanoparticles The colloidal suspension displayed enhanced antihyperglycemic activity at 69.97 ± 3.42% (leaf) against α-amylase (from porcine) and at 85.77 ± 5.82% (flower) against Bacillus stearothermophilus α-glucosidase than that of acarbose and their respective crude extracts. Furthermore, revealed good antibacterial activity against bacterial species Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa.
Vandana Singh; Devendra Singh
Abstract
In the present communication, we report on diastase alpha amylase immobilization at guar gum-silica nanohybrid material (H5). The immobilized amylase (H5-Amyl) showed significantly higher bioactivity (21.62 U mg -1 ) as compared to free amylase (15.59 U mg -1 ) in solution at pH 5 and temperature 40°C. ...
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In the present communication, we report on diastase alpha amylase immobilization at guar gum-silica nanohybrid material (H5). The immobilized amylase (H5-Amyl) showed significantly higher bioactivity (21.62 U mg -1 ) as compared to free amylase (15.59 U mg -1 ) in solution at pH 5 and temperature 40°C. The kinetic parameters of the free (Km = 10.66 mg L -1 ; Vmax = 1.36 µmolemL -1 .min -1 ) and the immobilized enzyme (Km = 6.11 mg mL -1 ; Vmax = 1.45 µmolemL -1 .min -1 ) revealed that the immobilization has increased the overall catalytic property of the enzyme. The immobilized enzyme on recycling could show 87% of initial activity even in the sixth cycle. Since immobilization did not hamper the enzymatic reaction rate, the biocatalyst may be suitably exploited in food and pharmaceutical industries.
