Chemical components and antibacterial activity of wild and artificially cultured Earliella scabrosa (Pers.) Gilb.& Ryvarden

Objective The effects of different media on the chemical components and antibacterial activity of ethyl acetate extract from Earliella scabrosa (Pers.) Gilb.& Ryvarden were investigated to provide theoretical basis for the artificial culture of E.scabrosa.Method E.scabrosa was artificially cultured in two different media,glucose-yeast-peptone medium (GYP) and comprehensive potato-dextrose-agar medium (CPDA) respectively.Ethyl acetate was used to extract the chemical components of mycelia and fermentation broths.The chemical components of ethyl acetate extracts from wild and artificially cultured E.scabrosa were comparatively analyzed by gas chromatography-mass spectrometry (GC-MS).The antibacterial activity of these extracts against Staphylococcus aureus and Escherichia coli were tested by microdilution method.Result GC-MS analysis showed that the main chemical components of the ethyl acetate extracts from wild and artificially cultured mycelia were methyl hexadecanoate,hexadecanoic acid,oleic acid,etc.Thirteen components were identified from the wild mycelia,and among them,the main components with high content were methyl linoleate (18.522%),methyl hexadecanoate (15.976%) and hexadecanoic acid (11.164%).Thirteen components were identified from the mycelia in GYP medium,and among them,the main components with high content were hexadecanoic acid (28.677%),oleic acid (15.108%),and methyl hexadecanoate (8.983%).Fourteen components were identified from the mycelia in CPDA medium,and among them,the main components with high content were methyl hexadecanoate (22.575%),hexadecanoic acid(17.643%),and methyl octadecanoate(4.787%).There were seven identical components existing in three extracts,and three components were only found in wild mycelia,and seven components were only detected in cultured mycelia.Nine components were identified in GYP culture medium,and among them,the main components with high content were octadecamethylcyclononasiloxane(4.663%),1-nonadecene(2.423%) and (E)-3-octadecene (1.785%).Fourteen components were identified in CPDA culture medium,and among them,the main components with high content were hexadecanoic acid (12.913 %),(Z,E)-2,13-octadecadien-1-ol (5.985%),and methyl hexadecanoate (5.591%).Antibacterial test in vitro showed that the ethyl actate extracts of the GYP culture medium had the strongest antibacterial activity against S.aureus with minimum inhibitory concentration(MIC) value of 0.80 mg/mL,while the MIC of other extracts against S.aureus and E.coli were all 1.60 mg/mL.ConclusionWild E.scabrosa can be cultured in scale in GYP and CPDA media to solve the problem of wild fungus resource shortage.