A Metering Method of Starch Granules Based on Optical Microscopy and its Application to Panax Notoginseng
Objective:To establish a metering method of starch granules based on optical microscopy and to applicate the method to Panax notoginseng.Methods:The starch granules were stained with dilute iodine solution and observed by an optical microscopy.Image J software was used for the auto measurement of the area percentage of starch granules in the slide.The concentration of dilute iodine solution,the concentration of sample,and the microscopic measurement zone were validated using the powder of Panax notoginseng as a sample.Results:Starch granules was well stained in a dilute iodine solution with a concentration of 0.002 mol/L.The density of starch granules in a sample with a concentration of 15 mg/mL was appropriate for measurement.The result was reliable when the microscopic measurement zones were nine.The RSD of precision,repeatability,reproducibility of the starch granules metering method were all<10.5%,indicating the method was stable and reliable.The starch granules in Panax notoginseng powder was metered by this method.The results indicated that there was significant difference of the starch granules of number different specifications and grades of Panax notoginseng.The area percentage of starch granules was in an order of 40-Tou>60-Tou>120-Tou>Coutless-Tou>Jintiao>Ronggen≈Jiankou.Conclusion:The metering method of starch granules established by optical microscopy is simple,fast and reliable.The method has been well applied to Panax notoginseng,and will effective support for the metering of starch granules in the plant materials.
starch granulesoptical microscopymetering methodpanax notoginsengspecifications and gradesImage J software