Background:Yam(Dioscorea opposita Thunb.)has been consumed as a food and used in traditional Chinese medicine for thousands of years.Resistant starch(RS)3 is of particular interest because it is heat-resistant,safe an...Background:Yam(Dioscorea opposita Thunb.)has been consumed as a food and used in traditional Chinese medicine for thousands of years.Resistant starch(RS)3 is of particular interest because it is heat-resistant,safe and non-toxic,and retains good nutritional benefits;it is therefore used in a wide range of traditional and emerging foods as a heat-stable prebiotic ingredient.In our previous study,we found that yam RS includes strong lipid-lowering and anti-constipation activities.Methods:Yam RS3 was prepared by autoclaving-retrogradation and pullulanase debranching to yield autoclaving-retrogradation yam RS and pullulanase debranching yam RS,respectively.First,the physicochemical properties of both RS3s were analyzed.Second,the structures of the RS3s were characterized by scanning electron microscopy,X-ray powder diffraction,and Fourier transform infrared spectroscopy.Finally,the regulatory effects of the RS3s on the gut microbiota were evaluated using an in vitro fecal fermentation model.Results:The RS content of the RS3s decreased after processing,but was higher in pullulanase debranching yam RS(35.67%)than in autoclaving-retrogradation yam RS(28.71%).Compared with native yam starch,RS3s lost their original granular shapes and instead exhibited irregularly shapes with continuous phases.The crystalline structure of the RS3s was completely altered,with pullulanase debranching yam RS exhibiting B-type patterns.Both RS3s,and especially pullulanase debranching yam RS,promoted a significant increase in short chain fatty acid content after in vitro fermentation(all P<0.05).Moreover,pullulanase debranching yam RS significantly increased the abundance of beneficial bacteria and decreased the abundance of harmful bacteria such as Escherichia and Shigella(all P<0.05).Conclusion:Our findings show that yam RS3s can regulate the composition of the gut microbiota and promote the production of short chain fatty acid,especially butyric acid.Pullulanase debranching was a more effective method for producing functional yam RS3.展开更多
以淀粉型甘薯为原料,利用单因素试验研究不同淀粉乳质量浓度、pH值、压热温度、压热时间及冷却回生时间对甘薯三型抗性淀粉(resistant starch type 3,RS3)得率的影响,并通过响应面设计优化制备工艺。结果显示,响应面试验得出的最优制备...以淀粉型甘薯为原料,利用单因素试验研究不同淀粉乳质量浓度、pH值、压热温度、压热时间及冷却回生时间对甘薯三型抗性淀粉(resistant starch type 3,RS3)得率的影响,并通过响应面设计优化制备工艺。结果显示,响应面试验得出的最优制备条件为淀粉乳浓度13%、pH5.5、压热温度110℃、压热时间35 min,此时RS3得率为37.94%,与预测值仅相差0.92%,响应面模型与实际情况拟合良好。甘薯抗性淀粉RS3的体外抗消化特性研究表明,RS3的酶解率和模拟消化道的消化率低,展示很强的抗酶解、抗消化特性。电镜结果显示,RS3颗粒呈不规则块状,表面凹凸不平;结晶型以B型为主,颗粒有序度降低,双螺旋程度和结晶度提高,与原淀粉相比结构更加紧密,这些结构特性可以解释甘薯RS3的抗消化特性。展开更多
基金the key project at central government level(No.2060302)Key R&D Project of Hebei Province(V1584581541757)+1 种基金the Science and Technology Project of Qinghai Province(No.2021-SF-150)the National Key R&D Program of China(No.2019YFC1710603,No.2019YFC1710604).
文摘Background:Yam(Dioscorea opposita Thunb.)has been consumed as a food and used in traditional Chinese medicine for thousands of years.Resistant starch(RS)3 is of particular interest because it is heat-resistant,safe and non-toxic,and retains good nutritional benefits;it is therefore used in a wide range of traditional and emerging foods as a heat-stable prebiotic ingredient.In our previous study,we found that yam RS includes strong lipid-lowering and anti-constipation activities.Methods:Yam RS3 was prepared by autoclaving-retrogradation and pullulanase debranching to yield autoclaving-retrogradation yam RS and pullulanase debranching yam RS,respectively.First,the physicochemical properties of both RS3s were analyzed.Second,the structures of the RS3s were characterized by scanning electron microscopy,X-ray powder diffraction,and Fourier transform infrared spectroscopy.Finally,the regulatory effects of the RS3s on the gut microbiota were evaluated using an in vitro fecal fermentation model.Results:The RS content of the RS3s decreased after processing,but was higher in pullulanase debranching yam RS(35.67%)than in autoclaving-retrogradation yam RS(28.71%).Compared with native yam starch,RS3s lost their original granular shapes and instead exhibited irregularly shapes with continuous phases.The crystalline structure of the RS3s was completely altered,with pullulanase debranching yam RS exhibiting B-type patterns.Both RS3s,and especially pullulanase debranching yam RS,promoted a significant increase in short chain fatty acid content after in vitro fermentation(all P<0.05).Moreover,pullulanase debranching yam RS significantly increased the abundance of beneficial bacteria and decreased the abundance of harmful bacteria such as Escherichia and Shigella(all P<0.05).Conclusion:Our findings show that yam RS3s can regulate the composition of the gut microbiota and promote the production of short chain fatty acid,especially butyric acid.Pullulanase debranching was a more effective method for producing functional yam RS3.
文摘以淀粉型甘薯为原料,利用单因素试验研究不同淀粉乳质量浓度、pH值、压热温度、压热时间及冷却回生时间对甘薯三型抗性淀粉(resistant starch type 3,RS3)得率的影响,并通过响应面设计优化制备工艺。结果显示,响应面试验得出的最优制备条件为淀粉乳浓度13%、pH5.5、压热温度110℃、压热时间35 min,此时RS3得率为37.94%,与预测值仅相差0.92%,响应面模型与实际情况拟合良好。甘薯抗性淀粉RS3的体外抗消化特性研究表明,RS3的酶解率和模拟消化道的消化率低,展示很强的抗酶解、抗消化特性。电镜结果显示,RS3颗粒呈不规则块状,表面凹凸不平;结晶型以B型为主,颗粒有序度降低,双螺旋程度和结晶度提高,与原淀粉相比结构更加紧密,这些结构特性可以解释甘薯RS3的抗消化特性。