Preparation of Sulfated Xylans and Its in Vitro Proliferation of Probiotics

This study aimed to determine the effect of sulfated xylans on the growth of probiotics. Xylan (Xyl) was chemically modified using the sulfamic acid-N,N-dimethylformamide method to produce sulfated xylan (SXY). The SXY was characterized by Fourier infrared spectroscopy (FT-IR), scanning electron microscope (SEM) and Congo red experiment. The Xyl and SXY were tested for their in vitro prebiotic effects using four strains of intestinal microflora, including Lactobacillus delbrueckii subsp. bulgaricus (GIM1.155), L. plantarum (GIM1.191), L. brevis (GIM1.773), and Streptococcus thermophilus (GIM1.540). From the recorded infrared spectra, vibrational bands for SXY were observed at 894, 1052 and 1243 cm⁻¹, they could be assigned to the C—O—S vibration of a C—O—SO₃, C—O stretched and S＝O stretching vibrations. The results of scanning electron microscopy showed that the surface structure of SXY increased smoothness. Congo red experiment revealed that SXY had a triple helix structure. The substitution degree of SXY measured using a BaCl₂-gelatin turbidimeter was 0.341. In vitro experiment showed that the optimum concentration of SXY for the in vitro probiotic growth was 2.0%, rapid growth and increased proliferation were observed after 10 h of culture. The results obtained suggest that SXY could promote probiotic growth. It is an alternate source of prebiotics for maintaining gut health.