Views: 7 Author: Liu Nannan, Li Jingyi Publish Time: 2023-09-12 Origin: Research progress on Pleurotus eryngii polysaccharides[J]. Chinese Food and Nutrition, 2018, 24(9):21-25.
Pleurotus eryngii is an edible mushroom of the genus Pleurotus. It originated in North Africa and the Middle East, the European Mediterranean region, and also grows in some parts of Asia. Pleurotus eryngii has the aroma of almonds, a taste similar to abalone, and thick flesh. It is both edible and medicinal. It has become very popular in recent years. . Pleurotus eryngii is rich in nutrients, low in fat and high in protein, and contains various amino acids necessary for the human body. In particular, its abundant polysaccharides are active substances that have received widespread attention in recent years. Modern scientific research has proven that Pleurotus eryngii polysaccharide is one of the main bioactive substances in Pleurotus eryngii, which has various physiologically active functions such as lowering blood sugar, lowering blood lipids, enhancing human immunity, scavenging free radicals in the human body, and anti-viral.
1. Structural analysis of polysaccharides
The biological activity of polysaccharides is closely related to its structure and spatial conformation. Therefore, a clear understanding of the structure of polysaccharides is crucial to studying their physiological activities. Research shows that after the polysaccharide is purified, the structure is further characterized through methylation analysis, nuclear magnetic resonance (NＲ), periodic acid oxidation, Smith degradation, enzymatic hydrolysis, spectroscopic analysis and chromatographic analysis. A water-soluble polysaccharide was extracted from the fruiting body of Pleurotus eryngii and subjected to DEAE Sapharose Fast Flow anion exchange chromatography and Sephacryl S-500 gel column chromatography to obtain a homogeneous component PEPSC1 with a molecular weight of 1.77×106Da. Gas chromatography analysis showed that PEPSC1 was composed of mannose and glucose, with a molar ratio of 1:10.3. The discarded Pleurotus eryngii culture medium was used to extract polysaccharides by alkaline method, and further purified to obtain polysaccharide-protein complex RPS, with a molar mass of 8.372×106g/mol. GC-MS analysis of monosaccharide components confirmed that RPS is a new type of Acidic heteropolysaccharides, mainly composed of xylose, glucose and arabinose.
2. Biological activity of Pleurotus eryngii polysaccharide
Anti-oxidize effect
Free radicals can induce oxidation reactions, cause changes in cell structure and loss of function, and hinder the normal development of cells. The pathological processes of many diseases such as aging, cardiovascular and cerebrovascular diseases, cancer, neurodegenerative diseases and autoimmune diseases are related to a large number of Free radicals and oxidation reactions. Relevant studies at home and abroad have found that polysaccharides in edible and medicinal fungi can scavenge free radicals, increase antioxidant enzyme activity, and have good effects on protecting biofilms and delaying aging. The superoxide anion scavenging rate of Pleurotus eryngii reached 68.89%, and the total antioxidant activity reached 138.05 μmol/g. Pleurotus eryngii crude polysaccharide and refined polysaccharide have strong scavenging ability for OH·, O2-· and DPPH, and the clearance rate gradually increases with the increase of their concentration. When the polysaccharide concentration is 1.8 mg/mL, Pleurotus eryngii has strong scavenging ability. The clearance rate of refined polysaccharide is 71.44%, and the clearance rate of crude polysaccharide of Pleurotus eryngii is 77.03%, but both are lower than vitamin C under the same conditions. Pleurotus eryngii polysaccharide has strong scavenging activity against DPPH free radicals, hydroxyl free radicals, and superoxide anion free radicals.
Antibacterial, antiviral
In recent years, more and more research at home and abroad has focused on the role of edible and medicinal mushrooms in inhibiting and alleviating chronic diseases such as diabetes and hyperlipidemia. According to literature reports, the mechanism of action of edible mushroom polysaccharides in lowering blood sugar is mainly to promote insulin secretion and regulate glucose levels. Regulation of metabolic enzyme activity promotes the action of peripheral tissues on glucose, thereby inhibiting gluconeogenesis. Oral administration of Pleurotus eryngii polysaccharide can reduce body weight, increase serum triglycerides, cholesterol, low-density lipoprotein, plasma insulin levels, and increase high-density lipoprotein and liver glycogen levels. Mice fed with high doses of Pleurotus eryngii mycelium polysaccharides had reduced weight gain, reduced liver lipid levels, increased peroxidase activity, and reduced lipid peroxidation levels.
Polysaccharides from edible fungi of the genus Pleurotus have inhibitory effects on a variety of viruses, such as AIDS virus (HIV-1), herpes simplex virus (HSV-1, HSV-2), influenza virus, etc. Most Pleurotus polysaccharides can inhibit the adsorption of viruses to cells. The mechanism may be that large molecules of Pleurotus polysaccharides can compete with viruses for cell binding sites.
