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One new indole diterpenoid, drechmerin I (1), was isolated from the fermentation broth of Drechmeria sp. isolated from the root of Panax notoginseng. Its structure was elucidated based on 1 D and 2 D nuclear magnetic resonance (NMR), high resolution electrospray ionization mass spectrum (HRESIMS), and electronic circular dichroism (ECD) spectroscopic analyses as well as TD DFT calculations of ECD spectra. Drechmerin I (1) was assayed for its antimicrobial activity against Candida albicans, Staphylococcus aureus, Bacillus cereus, B. subtillis, Pseudomonas aeruginosa, and Klebsiella pneumonia, respectively. Drechmerin I (1) showed antimicrobial activities against B. subtillis with an MIC value of 200 μg/mL. The interaction of S. aureus peptide deformylase with drechmerin I (1) was investigated by molecular docking. [ABSTRACT FROM AUTHOR]

Tailoring the crystallization process to realize targeted material texture/porosity is a major challenge in zeolite synthesis, which facilitates the practical application of zeolites. In the present work, core–shell structured ZSM-5 zeolites were successfully synthesized through a graphene oxide (GO)-assisted hydrothermal method and characterized by XRD, SEM, NH3-TPD and N2 adsorption–desorption analysis. GO sheets have dual roles in the formation of core–shell structured ZSM-5 zeolites. GO nanosheets attached to the outer surface of large ZSM-5 crystal cores not only tailor the growth of crystal planes but also induce the formation of ZSM-5 nanocrystal layers. Compared to the conventional ZSM-5 zeolite, due to the c-axis oriented ZSM-5 cores and unique core–shell structure, the core–shell structured ZSM-5 zeolites expose more accessible acidic sites and shorten the diffusion path for molecules, leading to an enhanced catalytic activity for the o-methylation of cyclohexanone with methanol. [ABSTRACT FROM AUTHOR]