Open AccessMagnetic soy protein isolate–bovine serum albumin nanoparticles preparation as a carrier for inulinase immobilisation
Author(s) -
Mikani Mohaddeseh,
Torabizadeh Homa,
Rahmanian Reza
Publication year - 2018
Publication title -
iet nanobiotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.366
H-Index - 38
eISSN - 1751-875X
pISSN - 1751-8741
DOI - 10.1049/iet-nbt.2017.0188
Subject(s) - inulinase , bovine serum albumin , chemistry , dispersity , glutaraldehyde , nuclear chemistry , immobilized enzyme , magnetic nanoparticles , chromatography , zeta potential , thermal stability , nanoparticle , enzyme , biochemistry , materials science , polymer chemistry , organic chemistry , nanotechnology
Magnetic nanoparticles (NPs) were functionalised with soy protein isolate (SPI) and bovine serum albumin (BSA) for inulinase immobilisation. The results revealed the nanomagnetite size of about 50 nm with a polydispersity index (PDI) of 0.242. The average size of the SPI NPs prepared by using acetone was 80–90 nm (PDI, 0.277), and SPI–BSA NPs was 80–90 nm (PDI, 0.233), and their zeta potential was around −34 mV. The mean diameter of fabricated Fe 3 O 4 @SPI–BSA NPs was <120 nm (PDI, 0.187). Inulinase was covalently immobilised successfully through glutaraldehyde on Fe 3 O 4 @SPI–BSA NPs with 80% enzyme loading. Fourier transform infrared spectra, field emission scanning electron microscopy, and transmission electron microscopy images provided sufficient proof for enzyme immobilisation on the NPs. The immobilised inulinase showed maximal activity at 45°C, which was 5°C higher than the optimum temperature of the free enzyme. Also, the optimum pH of the immobilised enzyme was shifted from 6 to 5.5. Thermal stability of the enzyme was considerably increased to about 43% at 75°C, and K m value was reduced to 25.4% after immobilisation. The half‐life of the enzyme increased about 5.13‐fold at 75°C as compared with the free form. Immobilised inulinase retained over 80% of its activity after ten cycles.