基于动力学过程的地黄润制科学内涵研究

Mechanism of moistening process of Rehmanniae Radix based on kinetic process

基于吸水动力学和膨胀动力学,结合水分相态、质构特性、成分含量量化表征地黄润制过程。对地黄润制过程的吸水与膨胀动力学进行非线性拟合,采用低场核磁共振与成像技术(LF-NMR/MRI)研究润制过程中水的相态及分布变化,采用质构仪研究质构特性的变化,并分析地黄不同润制时间的吸水率、膨胀率、水分相态、硬度、压缩循环功的相关性。结果表明,地黄吸水动力学和膨胀动力学均符合一级动力学过程,且吸水率、膨胀率均随润制温度的增加而增加,随药材个头的增大而减小。地黄润制过程中水分由外而内逐渐渗入,水的相态比例发生会显著变化,在16 h内自由水由0.825%增加到97.7%,束缚水由99.2%减少到2.33%。硬度、压缩循环功等物性指标在28 h内随润制时间增加逐渐下降;32 h时水分已均匀分布于整个药材,此时物性指标也趋于稳定。皮尔逊双变量相关性分析表明,润制时间、吸水率、膨胀率、自由水和束缚水相对含量、硬度、压缩循环功之间均具有显著相关性,说明采用吸水、膨胀动力学,LF-NMR/MRI,质构仪可以直观量化表征地黄润制过程,为阐明地黄润制传统经验的科学内涵提供了科学依据。

The moistening process of Rehmanniae Radix was characterized quantitatively by moisture phase,texture properties,and component content based on water absorption kinetics and expansion kinetics.Non-linear fitting of water absorption kinetics and expansion kinetics in the moistening process of Rehmanniae Radix was carried out.Low-field nuclear magnetic resonance and imaging(LF-NMR/MRI)technology was used to investigate the phase state and distribution changes of water during the moistening process.The Texture Analyzer was used for the determination of texture properties.The correlations between water absorption rate,expansion rate,water phase state,hardness,and compression cycle work of Rehmanniae Radix at different moistening time were analyzed.The results showed that the water absorption kinetics and expansion kinetics of Rehmanniae Radix were in accordance with the first-order kinetics.Moreover,the water absorption rate and expansion rate increased with the increase in temperature but decreased with the increase in the size of the medicinal materials.In the moistening process,the moisture was transferred from the outside to the inside,and the proportion of the moisture phase changed significantly.Within 16 hours,free water increased from 0.825%to 97.7%,while bound water decreased from 99.2%to 2.33%.Within 28 hours,the texture properties,such as hardness and compression cycle work,decreased gradually with the prolongation in moistening time.At 32 hours,water was evenly distributed throughout the whole medicinal material,and the texture properties also tended to be stable.Pearson correlation bivariate analysis showed that moistening time,water absorption rate,expansion rate,the relative content of free water and bound water,hardness,and compression cycle work were significantly correlated,suggesting that water absorption kinetics and expansion kinetics,LF-NMR/MRI,and Texture Analyzer could directly and quantitatively characterize the moistening process.This study is expected to provide a scientific basis for clarifying the scientific connotation of the moistening process of Rehmanniae Radix.