Study on the application of nanofibers in food active packaging has been a research hotspot in recent years.In this work,solution blow spinning(SBS)was applied to rapidly fabricate the polycaprolactone(PCL),polyvinyl ...Study on the application of nanofibers in food active packaging has been a research hotspot in recent years.In this work,solution blow spinning(SBS)was applied to rapidly fabricate the polycaprolactone(PCL),polyvinyl pyrrolidone(PVP),and PCL/PVP nanofibrous films to encapsulate chlorogenic acid(CGA).All films showed uniform and smooth nanofibers,and the Fourier transform infrared spectroscopy and X-ray diffraction proved the success of mixed spinning of PCL and PVP.With the increase of PVP content,the thermal stability of the PCL/PVP nanofibrous films improved.The PCL/PVP(weight ratio of 4:1)film possessed better mechanical properties than PCL and PVP films be-cause of the stronger fiber-fiber interactions.The addition of PCL endowed the hydrophobic surfaces to the PCL/PVP films,and the PCL/PVP films had better water vapor barrier ability.The PCL/PVP(4:1)film exhibited the best long-term continuous release of CGA during 72 h.The PVP nanofibrous film exhibited no inhibition against Staphylococcus aureus and Escherichia coli due to the low encapsulation efficiency,but the PCL and PCL/PVP films exhibited good antimicrobial activity.The above results suggested that the nanofibrous fims developed by SBS possess promising prospects in food packaging.展开更多
文摘为探讨干湿循环对三峡消落带狗牙根磷释放的影响,以三峡典型支流-澎溪河为例,选取上游(渠口镇)和下游(双江镇)两个水文断面, 150、160、170 m三个水位高程调查了狗牙根分布特征,并于干湿循环和持续淹水两种水文情势,15-25-35-25-15℃连续温度变化下进行培养,测定了水-土(W-S)、水-狗牙根(W-C)和水-土-狗牙根(W-S-C)三种体系下水中磷含量随时间变化。结果表明:狗牙根生物量随消落带水位高程降低而下降,表现为170m(1.62 kg·DW·m^-2)>160 m (0.85 kg·DW·m^-2)>150 m (0.19 kg·DW·m^-2)。在整个培养阶段,三种体系水中磷含量均随培养时间的延长而增加,表现为W-S-C>W-C>W-S体系,其释放动力学过程符合y=axb幂函数模型。与持续淹水相比,干湿循环影响下W-S-C体系中狗牙根磷释放量较低,可见,干湿循环有利于降低消落带狗牙根磷释放,降低三峡支流水体富营养化风险。
基金the Fundamental.Research Funds for the Central Universities(K20210202),Chinathe Zhejiang Provincial San Nong Jiu Fang’Science and Technology Collaboration Program of China(2022SNJF020).
文摘Study on the application of nanofibers in food active packaging has been a research hotspot in recent years.In this work,solution blow spinning(SBS)was applied to rapidly fabricate the polycaprolactone(PCL),polyvinyl pyrrolidone(PVP),and PCL/PVP nanofibrous films to encapsulate chlorogenic acid(CGA).All films showed uniform and smooth nanofibers,and the Fourier transform infrared spectroscopy and X-ray diffraction proved the success of mixed spinning of PCL and PVP.With the increase of PVP content,the thermal stability of the PCL/PVP nanofibrous films improved.The PCL/PVP(weight ratio of 4:1)film possessed better mechanical properties than PCL and PVP films be-cause of the stronger fiber-fiber interactions.The addition of PCL endowed the hydrophobic surfaces to the PCL/PVP films,and the PCL/PVP films had better water vapor barrier ability.The PCL/PVP(4:1)film exhibited the best long-term continuous release of CGA during 72 h.The PVP nanofibrous film exhibited no inhibition against Staphylococcus aureus and Escherichia coli due to the low encapsulation efficiency,but the PCL and PCL/PVP films exhibited good antimicrobial activity.The above results suggested that the nanofibrous fims developed by SBS possess promising prospects in food packaging.
