First report on the effect of <i>Hylotelephium erythrostictum</i> polysaccharides against <i>Toxoplasma gondii</i> infection

Beyond the extract, which protects the intestine <i>via</i> ROS scavenging and inhibition of JAK/STAT and JNK pathways, this study examines the anti-parasitic activity of <i>Hylotelephium erythrostictum</i> (Miq.) H. Ohba polysaccharides (HEPs). HEPs were isolated from <i>H. erythrostictum</i> (Miq.) H. Ohba <i>via</i> optimised hot-water extraction, Sevage deproteinization, and dialysis. Monosaccharide composition revealed HEPs are heteropolymers (Rha:Ara:Gal:Glc:GulUA ≈ 1.0:1.8:2.1:3.5:3.2), dominated by glucose (≈32 mol%) and unprecedented guluronic acid (GulUA, ≈28 mol%. SEC-MALLS-RI showed weight-average Mw = 37.78 kDa, number-average Mn = 5.20 kDa, indicating a bimodal distribution (≈38 kDa GulUA-rich and ≈5 kDa fractions). The lack of therapeutic selectivity in HEPs, due to their low selectivity index (SI ≈ 0.85), contrasts with their protective potency, which is comparable to the standard drug. These findings elucidate a unique architecture whose therapeutic potential against toxoplasmosis may be realised upon addressing the issue of low selectivity.