Ultrasonic-assisted extraction （UAE） of American ginseng polysaccharides （AGP） was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrason...Ultrasonic-assisted extraction （UAE） of American ginseng polysaccharides （AGP） was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrasonic power, extraction time and ratio of water to raw material to obtain a high AGP yield. The analysis of variance and response surface plots indicated that ultrasonic power was the most important factor affecting the extraction yield. The optimal conditions were ultrasonic power 400 W, extraction time 71 min, and ratio of water to raw material 33 mL g-1. Under these conditions, the yield of AGP was 8.09%, which was agreed closely to the predicted value. Gas chromatography （GC） analysis showed that AGP was composed of arabinose, rhamnose, galactose, glucose, and galacturonic acid. Fourier transform infrared spectra revealed the general characteristic absorption peaks of AGP. In addition, AGP exhibited good immunostimulating activities by up-regulating the production of nitric oxide and cytokines. Compared with hot water extraction, UAE required shorter extraction time and gave a higher extraction yield, without changing the structure and immunostimulating activity of AGP. The results indicated that UAE could be an effective and advisable technique for the large scale production of plant polysaccharides.展开更多
Ultrafiltration and a series of chromatographic steps were used to isolate and purify polysaccharides from Tremella aurantialba fruit bodies.Three crude fractions(TAP50w,TAP10-50w,and TAP1-10w),five semi-purified frac...Ultrafiltration and a series of chromatographic steps were used to isolate and purify polysaccharides from Tremella aurantialba fruit bodies.Three crude fractions(TAP50w,TAP10-50w,and TAP1-10w),five semi-purified fractions(TAPA-TAPE),and one purified fraction(TAPA1) were obtained.A sulfated derivative of TAPA1(TAPA1-s) was prepared by chemical modification.The immunostimulating activity of the polysaccharide fractions in vitro was determined using the mouse spleen lymphocyte proliferation assay.Of the three crude fractions tested,cell prolifera-tion rates were increased most by TAP50w.Furthermore,TAPA1-s was markedly more stimulatory than TAPA1,indicating that sulfonation was an effective way to enhance the immunostimulating activity of polysaccharide.展开更多
基金financially supported by the International Science & Technology Cooperation Program of China (2011DFG32500)the Sci & Tech Innovation Program of CAAS
文摘Ultrasonic-assisted extraction （UAE） of American ginseng polysaccharides （AGP） was investigated using response surface methodology. Three-factor-three-level Box-Behnken design was employed to optimize the ultrasonic power, extraction time and ratio of water to raw material to obtain a high AGP yield. The analysis of variance and response surface plots indicated that ultrasonic power was the most important factor affecting the extraction yield. The optimal conditions were ultrasonic power 400 W, extraction time 71 min, and ratio of water to raw material 33 mL g-1. Under these conditions, the yield of AGP was 8.09%, which was agreed closely to the predicted value. Gas chromatography （GC） analysis showed that AGP was composed of arabinose, rhamnose, galactose, glucose, and galacturonic acid. Fourier transform infrared spectra revealed the general characteristic absorption peaks of AGP. In addition, AGP exhibited good immunostimulating activities by up-regulating the production of nitric oxide and cytokines. Compared with hot water extraction, UAE required shorter extraction time and gave a higher extraction yield, without changing the structure and immunostimulating activity of AGP. The results indicated that UAE could be an effective and advisable technique for the large scale production of plant polysaccharides.
基金Project (No.2006BAD06B08) supported by the National Key Technology R & D Program of China
文摘Ultrafiltration and a series of chromatographic steps were used to isolate and purify polysaccharides from Tremella aurantialba fruit bodies.Three crude fractions(TAP50w,TAP10-50w,and TAP1-10w),five semi-purified fractions(TAPA-TAPE),and one purified fraction(TAPA1) were obtained.A sulfated derivative of TAPA1(TAPA1-s) was prepared by chemical modification.The immunostimulating activity of the polysaccharide fractions in vitro was determined using the mouse spleen lymphocyte proliferation assay.Of the three crude fractions tested,cell prolifera-tion rates were increased most by TAP50w.Furthermore,TAPA1-s was markedly more stimulatory than TAPA1,indicating that sulfonation was an effective way to enhance the immunostimulating activity of polysaccharide.
