Three-phase extraction of polysaccharide from Stropharia rugosoannulata: Process optimization, structural characterization and bioactivities

Abstract

The isolation of Stropharia rugosoannulata polysaccharide (SRP) by three-phase extraction was optimized, and its structure and biological activities were identified. The optimal extraction conditions were: mass fraction of ammonium sulfate, 20%; volume ratio of sample solution to t-butanol, 1:1.5; extraction temperature, 35°C. Under these conditions, the yield of SRP was 6.85% ± 0.13%. SRP was found to be composed of glucose (35.79%), galactose (26.80%), glucuronic acid (9.92%), fructose (8.65%), xylose (7.92%), fucose (4.19%), arabinose (3.46%) and rhamnose (3.26%), with the molecular weight of 27.52 kDa. The results of DPPH, hydroxyl, ABTS+ radical scavenging and reducing power tests showed that SRP had good antioxidant capacities. SRP had no cytotoxic effect on RAW264.7 macrophages at the concentrations of 25-200 μg/mL, and could significantly promote phagocytosis activity and cell migration according to CCK-8 assay, phagocytosis assay and cell scratch experiment. SRP can significantly stimulate the transcript expression levels of TNF-α, IL-1β and IL-6, as determined by RT-PCR and Western blot assays. SRP activated the TLR4/NF-κB signaling pathway, and autophagy also occurred. These results suggest that SRP is a safe antioxidant and immunomodulator, and that it can be used in the development of functional foods and/or pharmaceuticals.

Nutritional, Bioactive, and Flavor Components of Giant Stropharia (Stropharia rugoso-annulata): A Review

“…S. rugoso-annulata soluble polysaccharides are heteropolysaccharides, with glucose and galactose being the most common composing monosaccharides ( Table 2 ) [ 3 , 28 , 41 , 48 , 49 ]. They may also contain mannose, arabinose [ 28 ], fucose [ 41 ], glucuronic acid, ribose [ 49 ], fructose, xylose, and rhamnose [ 3 ]. Glucose is the most abundant monosaccharide in the soluble polysaccharides of the fruiting body [ 3 , 28 , 41 , 48 , 49 ].…”

“…They may also contain mannose, arabinose [ 28 ], fucose [ 41 ], glucuronic acid, ribose [ 49 ], fructose, xylose, and rhamnose [ 3 ]. Glucose is the most abundant monosaccharide in the soluble polysaccharides of the fruiting body [ 3 , 28 , 41 , 48 , 49 ]. Based on the presence or absence of acidic groups such as glucuronic acid or sulfate groups in the composition of monosaccharides, S. rugoso-annulata polysaccharides can be divided into neutral polysaccharides and acidic polysaccharides [ 26 , 28 , 49 ].…”

“…Recently, a new method, three-phase extraction, has been reported for the extraction of S. rugoso-annulata polysaccharides. This method utilizes a tert-butanol-(NH 4 ) 2 SO 4 -water system, which avoids the need for an alcohol precipitation process and achieves the separation of polysaccharides faster [ 3 ]. The highest yield from the S. rugoso-annulata fruiting body is achieved by an ultrasound-assisted extraction process (62 °C, 1:30 w / v , ultrasound 62 min), with a polysaccharide yield of 13.25% [ 37 ].…”

“…Stropharia rugoso-annulata , also known as Giant Stropharia, Wine-cap mushroom, is a renowned edible fungus recommended for consumption by the Food and Agriculture Organization of the United Nations due to its potential to alleviate various illnesses associated with cancer [ 1 ]. Not only is it a high-protein, low-fat food rich in minerals, vitamins, and dietary fiber [ 2 ], but it is also a quality raw material for functional components such as fungal polysaccharides [ 3 ], sterols [ 4 ], and taste peptides [ 5 ], and can also be processed into various flavorful foods [ 6 , 7 ]. With particularly simple cultivation techniques and high yield [ 8 ], it holds significant application value in various fields such as dietary nutrition supply, bioactive compound extraction, functional food production, and flavorful food processing.…”

Difference in Volatile Aroma Components of Stropharia rugosoannulata under Two Cultivated Environments Investigated by SPME-GC-MS

“…Stropharia rugosoannulata is a deciduous mushroom that belongs to the Strophariaceae family and is one of the top 10 mushrooms on the market [1]. It grows naturally in grassland or forest margins and is widely distributed in Asia, Europe, and America [1,2].…”