Degradation of Polysaccharides from Grateloupia filicina and Their Antiviral Activity to Avian Leucosis Virus Subgroup J

Abstract

In this study, polysaccharides from Grateloupia filicinia (GFP) were extracted and several low molecular weight (Mw) G. filicina polysaccharides (LGFPs) were prepared by the hydrogen peroxide (H2O2) oxidation method. Additionally, the effect of different experimental conditions on the degradation of GFP was determined. Results showed that the GFP degradation rate was positively related to H2O2 concentration and temperature, and negatively related to pH. Chemical analysis and Fourier transform infrared spectra (FT-IR) of GFP and LGFPs showed that the degradation caused a slight decrease of total sugar and sulfate content. However, there was no obvious change for monosaccharide contents. Then, the anti-ALV-J activity of GFP and LGFPs were determined in vitro. Results revealed that all of the samples could significantly inhibit ALV-J and lower Mw LGFPs exhibited a stronger suppression, and that the fraction LGFP-3 with Mw 8.7 kDa had the best effect. In addition, the reaction phase assays showed that the inhibition effect was mainly because of the blocking virus adsorption to host cells. Moreover, real-time PCR, western-blot, and IFA were further applied to evaluate the blocking effects of LGFP-3. Results showed that the gene relative expression and gp85 protein for LGFPS-3 groups were all reduced. Data from IFA showed that there was less virus infected cells for 1000 and 200 μg/mL LGFPS-3 groups when compared to virus control. Therefore, lower Mw polysaccharides from G. filicina might supply a good choice for ALV-J prevention and treatment.

Antiviral Activity against Avian Leucosis Virus Subgroup J of Degraded Polysaccharides from Ulva pertusa

“…The forward and reverse primers for ALV-J were 5′-TGCGTGCGTGGTTATTATTTC-3′ and 5′-AATGGTGAGGTCGCTGACTGT-3′, respectively; and the forward and reverse primer for internal control GAPDH were 5′-GAACATCATCCCAAGCGTCCA-3′ and 5′-CGGCAGGTCAGGTCAACAAC-3′. The real-time PCR were performed at 95°C for 30 s, 95°C for 5 s and 60°C for 34 s (34 cycles), 95°C for 15 s, and 60°C for 60 s [ 36 ].…”

Preprotection of Tea Polysaccharides with Different Molecular Weights Can Reduce the Adhesion between Renal Epithelial Cells and Nano-Calcium Oxalate Crystals

“…The cell membrane cannot be crossed when the molecular weights of the TPSs were large (e.g., 10.88 kDa of TPS0) [25,26]. However, the hydrogen chain was weak, and the active helical structure was not formed because of the short sugar chain [27,28] when the molecular weight of TPSs was small (such as 2.31 kDa of TPS3), thereby leading to a decrease in the protective effect. Thus, TPS2 with moderate molecular weight (4.82 kDa) was the most active.…”

Repair of Tea Polysaccharide Promotes the Endocytosis of Nanocalcium Oxalate Monohydrate by Damaged HK-2 Cells

“…When the polysaccharide's MW is too small (such as TPS3), the sugar chain is short and the hydrogen bonding is weak; as such, an active helical structure cannot easily form. Thus, excessive ROS in the damaged cells cannot be effectively removed, the repair effect is poor [51], and the ability to promote endocytosis is weak. Liao et al [52] also showed that polysaccharides with moderate MW of 1 × 10 5 − 4 × 10 5 Da have the highest activity, while those with low MW (5 × 10 3 − 1 × 10 4 Da) have no biological activity.…”