1.Comparison of Polysaccharide and Dendrobine Content in Hejiang Dendrobium nobile at Different Harvesting Time
Shou YAN ; Tingmei ZHAO ; Xueqin ZHANG ; Jiayi XING ; Yadong HU ; Ze CHUN
China Pharmacy 2018;29(1):73-77
OBJECTIVE:To determine quality indexes of Hejiang Dendrobium nobile at different harvesting time and months,and to provide scientific reference for reasonable harvesting period of Hejiang D.nobile.METHODS:The stem of annual,biennial and triennial D.nobile were collected.The drying rate,the contents of polysaccharides (colorimetry),dendrobine (GC) and total alkaloids (colorimetry),effective component total rate (dendrobine×drying rate) were measured.Biennial D.nobile were collected in autumn and winter (Oct.of the second year-Mar.of the third year,15th day a month) to determine drying rate,the contents of polysaccharides and dendrobine.RESULTS:The drying rate,the contents of polysaccharides and effective component total rate were higher than annual and triennial D.nobile.The content of total alkaloids and dendrobine were in descending order:annual D.nobile (0.52%,0.48%) >biennial D.nobile(0.48%,0.44%) >triennial D.nobile (0.32%,0.22%).From Oct.of the second year to Mar.of the third year,the drying rate of biennial D.nobile was increasing month by month;the contents of polysaccharides and dendrobine increased firstly and then decreased;the content of polysaccharide was the highest in Feb.(17.32%),and the content of dendrobine reached the highest level in Dec.(0.51%).CONCLUSIONS:The optimal harvesting period is biennial Hejiang D.nobile in Dec.and Jan.(third years before flowering),considering flowering characteristics,drying rate,the contents of polysaccharide and dendrobine.