A Comparative Study Between The Active Components Of Fresh And Dry Medicinal Houttuynia Cordata Thunb.

Houttuynia cordata Thunb.is a commonly used herbal medicines included by the Chinese Pharmacopoeia.This study takes the dry herb,fresh herb and different medicinal parts of H.cordata as the research object.The study comprises the following four aspects:· Screening of extraction methods of volatile oil from H.cordata and comparative analysis between the volatile oil of fresh and dry H.cordata GC-MS;· A study on the antibacterial and anti-inflammatory effects of volatile oil from H.cordata in vitro;· The Endophytic fungi was isolated and cultured from fresh H.cordata and comparative analysis between the volatile oil of endophytic fungi and fresh H.cordata;· Preliminary study on the chemical composition of dried H.cordata.The results show that:(1)Three extraction methods of volatile oil,including supercritical CO2 extraction,the ultrasonic assisted extraction and steam distillation,were screened from H.cordata.Finally,steam distillation was established as best method,based on the content of methyl nonyl ketone,one of the active ingredients of H.cordata.The volatile oil content of leaves was higher than stem,0.0737%and 0.0118%,respectively.(2)The antibacterial test results showed that the volatile oil of fresh and dry H.cordata had antibacterial activity against Staphylococcus aureus,Escherichia coli and Bacillus subtilis.And the antibacterial effects of volatile oil of fresh H.cordata was significantly better than volatile of dry H.cordata on the same concentration range.The anti-inflammatory activity of volatile oil of fresh H.cordata was investigated using acute topical edema model of the mouse ear,The result showed that the Percentile edema inhibition was more than 87%,with good anti-inflammatory effect,better than the positive control aspirin.(3)Three endophytic fungi were isolated from fresh H.cordata.Trans-2-decanoic acid was detected in volatile oil of endophytic fungi of fresh H.cordata.It has a similar structure with methyl nonyl ketone,one of bioactive compositions of H.cordata.These results suggest that it may be related to the metabolic pathways of methyl nonyl ketone.This study lay an experimental foundation for further research of the metabolites of endophytic fungi from fresh H.cordata.(4)Using thin layer chromatography,column chromatography separation methods to study the chemical compositions of dry H.cordata.The ?-sitosterol was isolated and identified from methanol extract of dry H.cordata.This study aimed to compare the active components and pharmacological activity between fresh and dry medicinal H.cordata,and provide the scientific basis for the rational development of H.cordata,and lay the foundation to explore the source of bioactive components of H.cordata.