Activity, stability and kinetic parameters for 𝛼-chymotrypsin catalysed reactions in AOT/isooctane reverse micelles with nonionic and zwitterionic mixed surfactants

Journal of Chemical Sciences

Kallol K Ghosh¹  Santosh Kumar Verma1² 

[1] School of Studies in Chemistry, Pt. Ravishankar Shukla University, Raipur 492 010, India$$;Shri Shankaracharya Institute of Technology and Management, Bhilai 490 020, India$$

关键词: 𝛼−Chymotrypsin;    stability;    𝑝-nitrophenyl acetate;    zwitterionic surfactants;    reverse micelles;   

DOI  :  

来源: Indian Academy of Sciences

【 摘 要 】

Reverse micelles (RMs) of sodium 1,4-bis(2-ethylhexyl)sulphosuccinate (AOT) in nonpolar organic solvents are widely known to have very high solubilization power for water. The method is applied to the hydrolysis of 𝑝-nitrophenyl acetate (PNPA) catalysed by 𝛼-chymotrypsin (𝛼-CT) in AOT/isooctane/buffer RMs. The increase in 𝛼-CT activity and stability was an optimum at wo ([H2O]/[AOT]) = 10, z [Isooctane]/[AOT]) = 5. Three typical surfactants were selected based on their head group charges: a non-ionic surfactant Triton-X 100 and two zwitterionic sulphobetaine surfactants of the type C𝑛H2𝑛+1N+Me2 (CH2)3 SO$^{−}_{3}$ (n = 10; SB3-10, n = 16; SB3-16). The kinetic parameters (such as 𝑘cat and 𝐾M) of the 𝛼-CT at 27°C were determined and compared in the absence and presence of three surfactants. The effect of chain length of zwitterionic surfactant (SB3-10 and SB3-16) on the enzymatic efficacy of 𝛼-CT as a function of mixed surfactant addition has been investigated in AOT/isooctane RMs at pH 7.75.

【 授权许可】

Unknown