Traditional Chinese Medicine (TCM) has been used to treat diseases in China for thousands of years. TCM compositions are complex, using as their various sources plants, animals, fungi, and minerals. Polysaccharides are one of the active and important ingredients of TCMs. Polysaccharides from TCMs exhibit a wide range of biological activities in terms of immunity- modifying, antiviral, anti-inflammatory, anti-oxidative, and anti-tumor properties. With their widespread biological activities, polysaccharides consistently attract scientist's interests, and the studies often concentrate on the extraction, purification, and biological activity of TCM polysaccharides. Currently, numerous studies have shown that the modification of polysaccharides can heighten or change the biological activities, which is a new angle of polysaccharide research. This review highlights the current knowledge of TCM polysaccharides, including their extraction, purification, modification, and biological activity, which will hopefully provide profound insights facilitating further research and development.

Staphylococcus saprophyticus (S. saprophyticus) is one of the main pathogens that cause serious infection due to its acquisition of antibiotic resistance. The efflux pump decreases antibiotic abundance, and biofilm compromises the penetration of antibiotics. It has been reported that baicalin is a potential agent to inhibit efflux pumps, biofilm formation, and quorum-sensing systems. The purpose of this study was to investigate whether baicalin can inhibit S. saprophyticus biofilm formation and the quorum-sensing system by inhibiting the MsrA efflux pump. First, the mechanism of baicalin inhibiting efflux was investigated by the ethidium bromide (EtBr) efflux assay, measurement of ATP content, and pyruvate kinase (PK) activities. These results revealed that baicalin significantly reduced the efflux of EtBr, the ATP content, and the activity of PK. Moreover, its role in biofilm formation and the agr system was studied by crystal violet staining, confocal laser scanning microscopy, scanning electron microscopy, and real-time polymerase chain reaction. These results showed that baicalin decreased biofilm formation, inhibited bacterial aggregation, and downregulated mRNA transcription levels of the quorum-sensing system regulators agrA, agrC, RNAIII, and sarA. Correlation analysis indicated that there was a strong positive correlation between the efflux pump and biofilm formation and the agr system. We demonstrate for the first time that baicalin inhibits biofilm formation and the agr quorum-sensing system by inhibiting the efflux pump in S. saprophyticus. Therefore, baicalin is a potential therapeutic agent for S. saprophyticus biofilm-associated infections.

Duck viral hepatitis (DVH) is an acute disease of young ducklings with few convenient and effective veterinary drugs to treat. In pathology, present study mainly focused on the immune mechanism, but very few studies have concerned with the role of oxidative stress in the pathogenesis of DVH. To study the antioxidative and hepatoprotective effects of icariin and its phosphorylated derivative against DVH, we prepared phosphorylated icariin (p-icariin) using the sodium trimetaphosphate–sodium tripolyphosphate method. Ducklings were drunk with icariin and p-icariin after being challenged with duck hepatitis virus 1 (DHV-1). We recorded the number of dead ducklings, gross pathological changes in the liver, and changes in indices of oxidative stress and liver injury. The correlations between these indices were also analyzed. Exposure to DHV-1 induced significant oxidative damage in ducklings. Administration of icariin or p-icariin attenuated liver pathological injury and significantly increased the survival rate, with better outcomes in ducklings treated with p-icariin than in those treated with icariin. Icariin and p-icariin also attenuated the changes in oxidative stress and liver injury. We found positive correlations among indices of oxidative stress (malondialdehyde and inducible nitric oxide synthase) and liver injury (alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase), suggesting that DHV-1 causes significant oxidative damage, which is related to the extent of hepatic injury. Icariin and p-icariin improved the survival and attenuated oxidative stress and liver dysfunction induced by DHV-1. These outcomes were better in ducklings treated with p-icariin than in those treated by icariin. The clinical effects of both components were related to their antioxidant activities.