Effects of L-Phenylalanine on Crystallization And Nucleation of L-Glutamic Acid

Abstract:

The effects of L-Phenylalanine(L-Phe) on crystallization and nucleation of L-Glutamic acid(L-Glu) were investigated in this study by = simulating L-glutamic acid precipitation process through changing pH of monosodium glutamate solution with diluted sulphuric acid.The results indicated that the amount of L-Phe did not affect the L-Glu solubility,but the addition of L-Phe could be absorbed and imbedded on the surface/inside of the crystals of LGlu, thus repressing the crystals production withβform and changing the size distribution of the crystals with a form(crystals sizes decreases with the increased L-Phe addition amount). The mathematical analysis/model revealed that the nucleation kinetics parameters,solid/liquid surface tension(σ),free energy(△G),critical nucleation radius(rc) and maximum nucleation rate(A) in L-Glu crystallization were reduced,leading a lower nucleation rate(J) of L-Glu when increasing the L-Phe addition amount.