1F-Fructofuranosylnystose

Thermal Stability of Fructooligosaccharides Extracted from Defatted Rice Bran: A Kinetic Study Using Liquid Chromatography-Tandem Mass Spectrometry

Thermal degradation kinetics of fructooligosaccharides (FOS) in defatted rice bran were studied at temperatures of 90, 100, and 110 °C. FOS extracted from rice bran and dissolved in buffers at pH values of 5.0, 6.0, and 7.0 were prepared for the thermal treatments. The residual FOS (including 1-kestose (GF2), nystose (GF3), and 1F-fructofuranosylnystose (GF4)) contents were determined using the ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) method. The results showed that the thermal degradation kinetics of GF2, GF3, and GF4 followed a first-order kinetic model. Thermal degradation rate constants (k values) of GF2, GF3, and GF4 at different temperature and pH values were estimated using the first-order kinetic equation and SAS 9.1. As a result, these k values decreased gradually as the pH of the sample increased from 5.0 to 7.0. The Arrhenius model was applied to describe the heat dependence of the k-values. The activation energy (Ea) was calculated for each case of GF2, GF3, and GF4 degradation at pH values of 5.0, 6.0, and 7.0. The result showed that rice bran FOS is very thermostable at neutral pH while more labile at acidic pH.

Ethylenediaminetetraacetic acid (EDTA) as an auxiliary tool in the electrospray ionization mass spectrometry analysis of native and derivatized beta-cyclodextrins, maltoses, and fructans contaminated with Ca and/or Mg

The effect of Ca(2+) (and Mg(2+)) and the disodium salt of ethylenediaminetetraacetic acid (EDTA), a well known Ca(2+) (and Mg(2+)) chelating agent, on the volatilization/ionization of carbohydrates by using electrospray ionization mass spectrometry has been studied. Model compounds such as maltoses (maltose to maltoheptaose), beta-cyclodextrins (beta-cyclodextrin, methyl-beta-cyclodextrin, heptakis(2,6-di-O-methyl)-beta-cyclodextrin, heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin, and 2-hydroxypropyl-beta-cyclodextrin) and fructans (sucrose, 1-ketose, nystose, and 1F-fructofuranosylnystose) were used.

Effects of ultra-high pressure on effective synthesis of fructooligosaccharides and fructotransferase activity using Pectinex Ultra SP-L and inulinase from Aspergillus niger

In this study, various levels of ultra-high pressure (UHP) were combined with the enzymatic synthesis of the fructooligosaccharide (FOS) using Pectinex Ultra SP-L and inulinase. The combination enhanced the FOS yields up to 2.5- and 1.5-fold, respectively, compared to atmospheric condition (0.1 MPa). However, the enzymatic reaction was dependent on the levels of pressure, the reaction times, and the initial sucrose concentrations. The combined UHP and inulinase showed that the maximum FOS yield (71.81%) was obtained under UHP at 200 MPa for 20 min with 300 g/L of initial sucrose as a substrate, while the FOS yield (57.13%) using Pectinex Ultra SP-L was obtained under UHP at 300 MPa for 15 min with 600 g/L of initial sucrose as a substrate. The FOS composition produced by Pectinex Ultra SP-L under the UHP was 1-kestose (GF₂), nystose (GF₃), and 1F-fructofuranosylnystose (GF₄), whereas the FOS produced by inulinase composed of only GF₂ and GF₃. The combined UHP is a useful tool in the industrial application for FOS production. Highlights UHP activated the activity of Pectinex Ultra SP-L yet inactivated inulinase Pressure level, time, and sucrose concentration significantly affect FOS yields under UHP UHP enhanced FOS production with time-saving benefits within 15-20 min.

[Antidepressant active constituents in the roots of Morinda officinalis How]

Five compounds having antidepressant activities have been isolated from the roots of Morinda officinalis, a Chinese traditional Yang-tonic drug. These compounds were identified as succinic acid (1), nystose (2), 1F-fructofuranosylnystose (3), inulin-type hexasaccharide (4) and heptasaccharide (5) by chemical and spectroscopic methods. All of the compounds are isolated from the species of genus Morinda for the first time.