Studies On The Secondary Metabolites And Activities Of A Strain Gingko Endophytic Funfi

The Ginkgo biloba endophytic fungi possess structurally diverse secondary metaboliteswith complex skeletons. There are reports show most of the metabolites have unique medicalbioactivities, such as: antitumor, anti-inflammatory, anti-oxidation, and cytotoxic activity. So,in order to get new compounds which have good medicinal activity, and to offer significantfoundation for research of new medicines, the study of the secondary metabolite which areisolated from Ginkgo biloba endophytic fungi has become a hotspot for research in the fieldof natural product chemistry.As a continuious research on endophytes from plants, the chemical constituents from thefermentation broth of Ginkgo biloba endophytic fungi were investaged in the traditionalmethods. The secondary metabolites and antioxidation and allelopathic activity of endophyticfungus from Ginkgo biloba are studied. The six compounds were isolated from the fungus andthe structures were identified on the basis of NMR and MS: ribofuranoside（1）, adenine（2）,adenosine（3）,2′-deoxyadenosine（4）,2′-deoxyuridine（5）,3-methylpiperazine-2,5-dione（6）.All the compounds was assayed for antioxidation and allelopathic activity. Theantioxidation activity results showed that compounds3and4exhibited potential scavengingactivities compared with positive control group, the IC50are2.87μg/mL and8.37μg/mL，respectively, while the other compounds showed weak or little activity (IC₅₀>100μg/mL). Inaddition, almost compounds showed the enhancement effects for seed germination,compounds2and4were found to exhibit marked allelopathic activity for the Brassicachinensis L seed germination with EC50values of76.63μg/mL and54.06μg/mL, respectively,while, the root, and epicotyl growth were stimulated inapparently. The final activity resultsprovide atheoretical basis for investaging the bioactive of these compounds.