Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-com...Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP.展开更多
The objective of this work was to investigate and compare the structural and physicochemical properties of Dioscorea opposita Thunb. flour（DF）, starch（DS） and purified starch（PDS）. DS and PDS showed higher total...The objective of this work was to investigate and compare the structural and physicochemical properties of Dioscorea opposita Thunb. flour（DF）, starch（DS） and purified starch（PDS）. DS and PDS showed higher total starch and amylose content as compared to DF. Starch granules of DF were oval shape with rough surface while DS and PDS were relatively smooth by SEM. According to XRD measurements, FT-IR spectroscopy and 13 C CP/MAS NMR spectroscopy, all samples displayed C-type crystalline pattern, and PDS displayed the highest relative crystallinity and short-range order structure. However, DF contained the greatest content of the amorphous-phase. DF displayed the absorption peaks at 1730 and 1560 cm^-1 related to the characteristic groups of lipid and protein using FT-IR spectroscopy. Furthermore, DF exhibited significantly higher pasting temperature while DS displayed the great peak and breakdown viscosity, as well as PDS had the highest setback and final viscosity, presumably due to the chemical composition and structural differences. DF exhibited the highest gelatinization temperature whereas PDS displayed the greatest gelatinization enthalpy. The pasting and gelatinization properties of flour and starch might be related to the relative crystallinity, short-range order structure or the interactions between starch and its associated compounds. The results allow the improvement in the manufacture of Dioscorea opposita Thunb. flour and starch with desirable pasting and gelatinization properties.展开更多
利用响应面法优化了纤维素酶法提取山药(Dioscorea opposita Thunb)多糖的工艺条件。在单因素试验的基础上,采用响应面法对提取时间、提取温度、p H 3个因素进行优化,建立了山药多糖提取率的二次回归方程,通过响应面分析及岭嵴分析得到...利用响应面法优化了纤维素酶法提取山药(Dioscorea opposita Thunb)多糖的工艺条件。在单因素试验的基础上,采用响应面法对提取时间、提取温度、p H 3个因素进行优化,建立了山药多糖提取率的二次回归方程,通过响应面分析及岭嵴分析得到最优提取工艺为料液比1∶20(m/V,g∶m L),加酶量12 U/g,提取温度42℃、提取时间163.5 min,p H 4.09,该条件下山药多糖的提取率为6.082%。展开更多
基金the financial support provided by Zhengzhou 1125 Talents Gathering Project (2018)the Doctor startup fund of Henan Agricultural University (30500431)
文摘Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP.
基金Supported by the National Natural Science Foundation of China(No.31701552)Leading Talents Support Program of Science and Technology Innovation in Fujian Province(KRC16002A)Excellent Talents Support Program of Colleges and Universities in Fujian Province(JA14094)
文摘The objective of this work was to investigate and compare the structural and physicochemical properties of Dioscorea opposita Thunb. flour（DF）, starch（DS） and purified starch（PDS）. DS and PDS showed higher total starch and amylose content as compared to DF. Starch granules of DF were oval shape with rough surface while DS and PDS were relatively smooth by SEM. According to XRD measurements, FT-IR spectroscopy and 13 C CP/MAS NMR spectroscopy, all samples displayed C-type crystalline pattern, and PDS displayed the highest relative crystallinity and short-range order structure. However, DF contained the greatest content of the amorphous-phase. DF displayed the absorption peaks at 1730 and 1560 cm^-1 related to the characteristic groups of lipid and protein using FT-IR spectroscopy. Furthermore, DF exhibited significantly higher pasting temperature while DS displayed the great peak and breakdown viscosity, as well as PDS had the highest setback and final viscosity, presumably due to the chemical composition and structural differences. DF exhibited the highest gelatinization temperature whereas PDS displayed the greatest gelatinization enthalpy. The pasting and gelatinization properties of flour and starch might be related to the relative crystallinity, short-range order structure or the interactions between starch and its associated compounds. The results allow the improvement in the manufacture of Dioscorea opposita Thunb. flour and starch with desirable pasting and gelatinization properties.
文摘利用响应面法优化了纤维素酶法提取山药(Dioscorea opposita Thunb)多糖的工艺条件。在单因素试验的基础上,采用响应面法对提取时间、提取温度、p H 3个因素进行优化,建立了山药多糖提取率的二次回归方程,通过响应面分析及岭嵴分析得到最优提取工艺为料液比1∶20(m/V,g∶m L),加酶量12 U/g,提取温度42℃、提取时间163.5 min,p H 4.09,该条件下山药多糖的提取率为6.082%。
