Effects of extraction methods on the antioxidant activities of polysaccharides from Agaricus blazei Murrill.

Five polysaccharides were obtained from Agaricus blazei Murrill (ABM) through different extraction methods including hot water extraction, single enzyme extraction (pectinase, cellulase or papain) and compound enzymes extraction (cellulase:pectinase:papain). Their characteristics such as the polysaccharide yield, polysaccharide content, protein content, infrared spectra were determined, and antioxidant activities were investigated on the basis of hydroxyl radical, DPPH free radical, ABTS free radical and reducing power. The results showed that five extracts exhibited antioxidant activities in a concentration-dependent manner. Compared with other methods, the compound enzymes extraction method was found to present the highest polysaccharides yield (17.44%). Moreover, compound enzymes extracts exhibited the strongest reducing power and highest scavenging rates on hydroxyl radicals, DPPH radicals and ABTS radicals. On the contrary, hot water extraction method had the lowest polysaccharides yield of 11.95%, whose extracts also exhibited the lowest antioxidant activities. Overall, the available data obtained in vitro models suggested that ABM extracts were natural antioxidants and compound enzymes extraction was an appropriate, mild and effective extracting method for obtaining the polysaccharide extracts from Agaricus blazei Murrill (ABM).

Jia S ，Li F ，Liu Y ，Ren H ，Gong G ，Wang Y ，Wu S ... -  《-》

Drying effects on the antioxidant properties of polysaccharides obtained from Agaricus blazei Murrill.

Three polysaccharides (ABMP-F, ABMP-V, ABMP-A) were obtained from Agaricus blazei Murrill via methods such as freeze drying, vacuum drying and air drying, respectively. Their chemical compositions were examined, and antioxidant activities were investigated on the basis of assay for hydroxyl radical, DPPH radical, ABTS free radical scavenging ability and assay for Fe(2+)-chelating ability. Results showed that the three ABMPs have different physicochemical and antioxidant properties. Compared with air drying and vacuum drying methods, freeze drying method resulted to ABMP with higher neutral sugar, polysaccharide yield, uronic acid content, and stronger antioxidant abilities of hydroxyl radical, DPPH radical, ABTS radical scavenging and Fe(2+)-chelating. As a result, Agaricus blazei Murrill polysaccharides are natural antioxidant and freeze drying method serves as a good choice for the preparation of such polysaccharides and should be used to produce antioxidants for food industry.

Wu S ，Li F ，Jia S ，Ren H ，Gong G ，Wang Y ，Lv Z ，Liu Y ... -  《-》

Antioxidant property of water-soluble polysaccharides from Poria cocos Wolf using different extraction methods.

Poria cocos Wolf is a popular traditional medicinal plant that has invigorating activity. Water-soluble polysaccharides (PCPs) are its main active components. In this study, four different methods were used to extract PCPs, which include hot water extraction (PCP-H), ultrasonic-assisted extraction (PCP-U), enzyme-assisted extraction (PCP-E) and microwave-assisted extraction (PCP-M). Their chemical compositions and structure characterizations were compared. In vitro antioxidant activities were studied on the basis of DPPH radical, hydroxyl radical, reducing power and metal chelating ability. The results showed that PCPs were composed of mannose, glucose, galactose, and arabinose, and had typical IR spectra characteristics of polysaccharides. Compared with other PCPs, PCP-M had lower neutral sugar content, higher mannose content and higher uronic acid content. The molecular weight were determined as PCP-E<PCP-M<PCP-U<PCP-H. PCP-M showed the strongest reducing power and highest scavenging abilities on hydroxyl and DPPH radicals, while PCP-U exhibited the lowest antioxidant activities. Response surface methodology was used to optimize the extraction yield of PCP-M by implementing the Box-Behnken design. Under the optimized conditions, the PCP-M yield was 9.95%, which was well in close agreement with the value predicted by the model. Overall, the microwave-assisted extraction was an effective and mild method for obtaining antioxidant polysaccharides from P. cocos Wolf.

Wang N ，Zhang Y ，Wang X ，Huang X ，Fei Y ，Yu Y ，Shou D ... -  《-》

Effect of extraction method on structure and antioxidant activity of Hohenbuehelia serotina polysaccharides.

The impacts of four extraction methods (hot water, enzyme assistance, ultrasonic assistance and ultrasonic-enzyme assistance) on the extraction yields, preliminary structure and antioxidant activities of the Hohenbuehelia serotina polysaccharides (HW-HSP, EA-HSP, UA-HSP and UEA-HSP) were systematically investigated. The yield of the polysaccharides (20.70±0.17%) obtained by ultrasonic-enzyme assistance was higher than the polysaccharides by other methods'. Four kinds of polysaccharides possessed the different preliminary structural characteristics including molecular weight distributions, monosaccharide compositions, crystallization and spiral structures, while different surface morphology. Through the measurements of antioxidant activities in vitro, UEA-HSP exhibited the most significant scavenging capacities on non-physiological ABTS free radicals and physiological hydroxyl radicals. These data showed that ultrasonic-enzyme assistance was more beneficial to enhance the extraction yields of the polysaccharides, and obtain higher bioactive polysaccharides. The results also suggested that H. serotina polysaccharides possessed potential healthcare application in food field due to their antioxidant activities.

Li X ，Wang L 《-》

The Optimization of the Hot Water Extraction of the Polysaccharide-Rich Fraction from Agaricus bisporus.

Khalil ASE ，Lukasiewicz M 《MOLECULES》