Rapid HPLC method for monitoring of lactulose production with a high yield

Carbohydr Res. 2019 Oct 1:484:107773. doi: 10.1016/j.carres.2019.107773. Epub 2019 Aug 6.

Abstract

An HPLC method suitable for rapid monitoring of lactulose production by isomerization from lactose was developed. The separation of lactose and lactulose under hydrophilic interaction liquid chromatography (HILIC) mode was achieved with resolution 1.5 within 5 min. Since isocratic elution was used, there is no extra time necessary for the column equilibration. Application of the method was illustrated on monitoring lactulose isomerization with catalysis of sodium hydroxide in the presence of sodium tetraborate at 70 °C (pH = 11). The conversion yield obtained for lactulose was 86%, and corresponding purity 76%. For the first time, a polyhydroxy stationary phase for separation of lactose and lactulose is reported.

Keywords: Determination; Hydrophilic interaction liquid chromatography; Lactose; Lactulose production; Monitoring.

MeSH terms

  • Borates / chemistry
  • Catalysis
  • Chemical Fractionation / methods*
  • Chromatography, High Pressure Liquid
  • Hot Temperature
  • Hydrophobic and Hydrophilic Interactions
  • Isomerism
  • Lactose / analysis
  • Lactose / chemistry*
  • Lactulose / analysis*
  • Lactulose / chemistry
  • Sodium Hydroxide / chemistry

Substances

  • Borates
  • Lactulose
  • Sodium Hydroxide
  • sodium borate
  • Lactose