Two new metabolites from Daldinia eschscholtzii,an endophytic fungus derived from Pogostemon cablin

The chemical investigation of the mycelia of endophytic fungus Daldinia eschscholtzii A630, which was isolated from the medicinal plant Pogostemon cablin, resulted in the isolation of two new compounds, named eschscholin A (1), 3-ene-2-methyl-2H-1-benzopyran-5-ol (2), and one new natural product 3,5-dihydroxy-2-methyl-4H-chromen-4-one (3), along with seven known compounds. Their structures were fully characterized by means of detailed spectroscopic analysis, and in comparison with published data for known compounds. All of the isolated compounds (1–10) were evaluated for their antibacterial activities.     

药用真菌炭球菌生药学研究

目的：对吉林省药用真菌炭球菌进行生药学研究,为其药用开发提供鉴别依据.方法：采集炭球菌子实体,通过性状鉴别和孢子与菌丝显微特征观察,结合文献资料鉴定种类.利用薄层色谱建立炭球菌专属性薄层鉴别特征,利用高效液相色谱法测定其化学成分含量.结果：经性状及显微特征研究,确定为药用真菌“炭球菌Daldinia concentrica （Bolt.：Fr.） Ces.＆ dr Not.”.薄层鉴别研究发现具有多个专属性的薄层色谱斑点,并含有麦角甾醇成分.高效液相色谱法测定其麦角甾醇含量为0.16％.结论：通过炭球菌性状鉴别、光学显微镜和扫描电镜下孢子和菌丝特征、薄层鉴别图谱等,可综合鉴别炭球菌的真伪,为其鉴别提供了参考依据,麦角甾醇含量可作为其质量控制的指标之一.     

A new chromone and a new aliphatic ester isolated from Daldinia eschscholtzii

Abstract

A new chromone and a new aliphatic ester were isolated from the EtOAc extract of myceliums of Daldinia eschscholtzii. Their structures were elucidated as (R)-5-hydroxy-8-methoxy-2-methylchroman-4-one (1) and (E)-6-(non-3-en-1-yl) -2H-pyran-2-one (2) by interpretation of the spectroscopic evidence.     

Inhibitory activity of nitric oxide production in RAW 264.7 cells of daldinals A–C from the fungus Daldinia childiae and other metabolites isolated from inedible mushrooms

Three benzophenone derivatives, daldinals A–C, from the Japanese fungus Daldinia childiae were evaluated for their inhibitory activity of nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in RAW 264.7 cells. They strongly suppressed the LPS-induced production of NO with IC₅₀ values of 15.2, 4.6 and 6.4 μM, respectively. To clarify the mechanism involved, total RNA extraction, followed by reverse-transcribed, polymerase chain reaction (PCR) for inducible nitric oxide synthase (iNOS) mRNA and finally electrophoresis on agarose gel were performed. These experimental results suggest that the inhibition of the LPS-induced NO production of daldinal B is due to the inhibition of iNOS mRNA synthesis. Further, their biological activities were compared with those of other metabolites obtained during our studies on biologically active substances from inedible fungi in recent years.