Reactive oxygen species are known to have a role in ageing and in the pathogenesis of certain diseases such as cancer and atherosclerosis. Oxidation of biomolecules, which includes lipid peroxidation, is associated with several types of biological damage and with rancidity of food oils. There is therefore considerable interest in the use of antioxidants, especially from natural sources, to inhibit lipid peroxidation and protect biomolecules from oxidative damage.

Studies have shown that the mushroom Ganoderma lucidum, known as Ling Zhi in China, possesses strong antioxidant activity. The polysaccharides of G. lucidum have been identified as the bioactive components responsible for its anticancer and immunostimulatory effects. However, it is less clear which components are for the antioxidant activity of the mushroom; polysaccharide, polysaccharide-protein, phenolic and bioactive peptide constituents have all been shown to possess antioxidant activity.

Bioactive peptides are easily absorbed by the human intestine, and research has shown that the G. lucidum peptides (GLP) fraction has more potent hydroxyl free radical scavenging activity than the protein and polysaccharide fractions. This component could therefore be a potential antioxidant for biological and foods systems.

Sun et al.¹, evaluated and characterized the antioxidant activity of GLP using various assays. Inhibition by GLP of lipid peroxidation was studied in soybean oil and lard systems and in biological systems (mitochondrial membranes and rat hepatic tissue homogenates), and free radical scavenging activities of GLP were assessed. GLP showed potent antioxidant activity in both food systems, the activity in soybean oil was higher than that of butylated hydroxytoluene (BHT). It is therefore concluded that GLP is a major constituent responsible for the antioxidant activity of G. lucidum, possessing antioxidant and free radical scavenging activities.

¹ Sun, J; He, H; Xie, BJ (2004). Novel antioxidant peptides from fermented mushroom Ganoderma lucidum. Journal of Agricultural and Food Chemistry 52 (21) 6646–6652.

Click on the logo below to view an abstract of this paper from FSTA Direct.