ABSTRACT
Objective To observe the protection of human lens epithelial cells(HLEC) by different polar alkaloids extracted from Herba Dendrobii(HD).Methods We extacted the Herba Dendrobii powder with ethanol,and then treated the extract with falling-film concentration,acidification,salting out,chloroform extraction,and washing with water.Different polar alkaloids were extracted from HD after the above treatment.The protective effect of HD alkaloids was observed on HLEC,which were cultured with DMEM medium containing 10% fetal calf serum.Ten groups were set up for the experiment: normal control group,model group,high-and low-dose water-soluble alkaloids groups,high-and low-dose fat-soluble alkaloids groups,high-and low-dose low-polar alkaloids group,and high-and low-dose weak-polar alkaloids groups.The high-dose dosage of the alkaloids was 25.0 ?g/L and low-dose dosage was 12.5 ?g/L.Methyl thiazolyl tetrazolium(MTT) assay was used to evaluate the proliferation of HLEC under the different conditions of interventions.Results The single-factor experiments showed that the highest extracting rate of HD alkaloids was obtained under the conditions of extracting the powder with 80% ethanol for 3 times and for 3 hours.The results of protective experiment showed that the proliferation of HLEC in the model group was inhibited by hydrogen peroxide(H2O2),and the inhibitive rate was lower in low-dose fat-soluble alkaloids group than that in the model group(P