The mushroom Inonotus obliquushas been widely used as a folk medicine in Russia, Poland and most of the Baltic countries. In this study, water-soluble and alkali-soluble crude polysaccharides (IOW and IOA) were isolated from I. obliquus, and the carbohydrate-rich fractions IOW-1 and IOA-1 were obtained respectively after deproteination and depigmentation. Their contents, such as neutral carbohydrate, uronic acid and protein, were measured. Their antioxidant properties against chemicals-induced reactive species (ROS) including 1,1'-Diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical and superoxide anion radical, as well as their protective effects on H2O2-induced PC12 cell death were investigated. Results showed that I. obliquus polysaccharides can scavenge all ROS tested above in a dose-dependent manner. IOA and its product IOA-1 could rescue PC12 cell viability from 38.6% to 79.8% and 83.0% at a concentration of 20µg/mL. Similarly, IOW and its product IOW-1 at the same dose, can also increase cell viability to 84.9% and 88.6% respectively. The antioxidative activities of water-soluble and alkali-soluble polysaccharide constituents from I. obliquus might contribute to diverse medicinal and nutritional values of this mushroom.
1 August 2020 in International Journal of Biological Macromolecules
Bacteria on living or inert surfaces usually form biofilms which make them highly resistant to antibiotics and immune clearance. Herein, we develop a simple approach to overcome the above conundrum through lysozyme-associated liposomal gentamicin (LLG). The association of lysozyme to the surface of liposomes can effectively reduce the fusion of liposomes and undesirable payload release in regular storage or physiological environments. The LLG was more effective at damaging established biofilms and inhibiting biofilm formation of pathogens including Gram-positive and Gram-negative bacteria than gentamicin alone. This strategy may provide a novel approach to treat infections due to bacterial biofilm.