摘要
目的鉴定一株分离自海南文昌红海榄茎的内生真菌菌株AGR12,分离和鉴定其抑菌活性代谢产物。方法根据菌株的形态学特征和ITS序列鉴定菌株AGR12。通过硅胶柱层析、Sephadex LH-20凝胶柱层析、制备薄层层析及重结晶等方法分离纯化代谢产物,并根据它们的紫外、质谱、氢谱和碳谱等光谱数据确定化合物结构。结果菌株AGR12被鉴定为镰孢霉属木贼镰刀菌(Fusarium equiseti),其在优化后的GMPY培养基中28℃、160r/min振荡培养7d后获得的发酵液具有明显的抑菌活性。从发酵液及菌体中共分离到3个化合物,鉴定为equisetin、epi-equisetin和麦角甾醇(ergosterol),其中equisetin对枯草芽孢杆菌和金黄色葡萄球菌的生长具有明显的抑制活性,最低抑菌浓度(MIC)均为32μg/mL;epi-equisetin对枯草芽孢杆菌的生长也具有明显的抑制作用,MIC为32μg/mL。结论木贼镰刀菌菌株AGR12为首次从红树植物中分离到的内生真菌,其分泌的代谢产物equisetin和epi-equisetin具有明显的抑菌活性。
Objective To identify the endophytic fungus strain AGR12 isolated from the stem of Rhizophora stylosa Griff, and to investigate its active metabolites. Methods Morphological observation and internal transcribed spacer（ITS） sequence were applied to identify the strain AGR12. Silica gel column chromatography, Sephadex LH-20, preparative thin layer chromatography （pTLC）, and recrystallization were used to separate and purify the metabolites. The compounds which produced by the fungus strain AGR12 were elucidated by means of spectral analysis including ESI-MS, tH-NMR, 13C-NMR and UV. Results The strain AGR12 was identified as Fusarium equiseti, it could secrete antibacterial metabolites after being cultured on the modified GMPY medium under the condition of 28℃ in a rotary shake at 160r/min for 7 days. Three compounds were separated from the n-butanol extracts of fermentation broth and mycelium extracts. They were elucidated as equisetin, epi-equisetin and ergosterol, among which equisetin showed antibacterial activity against Bacillus subtilis and Staphyloccocus aureus with the minimum inhibitory concentration （MIC） of 32μg/mL respectively, while epi-equisetin could inhibit the growth of Bacillus subtilis with MIC of 32μg/mL. Conclusion Fusarium equiseti strain AGR12 is first reported as an endophytie fungus from the stem of mangrove plant, it can secrete equisetin and epi-equisetin which showed significant antibacterial activity.
出处
《中国抗生素杂志》
CAS
CSCD
北大核心
2011年第2期102-106,128,共6页
Chinese Journal of Antibiotics
基金
教育部"新世纪优秀人才支持计划"项目(No.NCET-05-0496)
