Natural Products Journal, The - Online First

Marine fungi have been recognized as new sources for the discovery of valuable secondary metabolites, providing lead compounds for drug discovery and development.

The objective of this study was to isolate and identify the secondary metabolites from the marine-derived fungus Trichoderma harzianum ZN-4 and evaluate their antifungal activity.

Fungus strain Trichoderma harzianum ZN-4 was initially fermentated using a PDB liquid medium. Subsequently, extensive chromatographic methods were applied to isolate the fermentation cultures of ZN-4, and the chemical structures of isolate compounds were elucidated by 1D and 2D NMR, ECD, and HRESIMS. The antifungal activity was evaluated using the broth microdilution method.

Three new butenolides, harzianolides H–J (1–3), were isolated from T. harzianum ZN-4, and cultivated on a sterilized PDB medium. Activity evaluation showed that compounds 1−3 exhibited potent antifungal activity with MIC values of 12.5−100 μg/mL against the phytopathogenic fungus Pestalotiopsis theae.

This study not only enriched the structural diversity of the harzianolide family but also revealed their anti-P. theae activity, which may be potential antifungal agents.

Diabetic foot ulcers (DFUs) constitute one of the most debilitating complications of diabetes mellitus (DM). The use of topical herbal products as adjuvant agents in wound dressing is one of the most widely used practices worldwide. The present review aimed to provide a detailed and comprehensive systematic review focusing on randomized clinical studies and critically analyze not only the clinical outcomes but also the methodological approaches used by these studies.

The present systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. For the extraction of relevant studies, three databases were searched: Pubmed, Web of Science Core Collection, and Scopus by two independent researchers.

A search of the three databases resulted in the identification of 5528 records which were reduced to 3224 after removal of duplicates. The application of inclusion and exclusion criteria left 35 full-text articles assessed for eligibility. Finally, 13 articles were excluded and only 22 articles were advanced to the final analysis. Most studies reported details of local ulcer management only while others reported the additional systemic/surgical measures used for management. The present review identified 18 botanical agents/preparations used alone or in combination with other agents as adjuvant agents in treatment of DFUs. In most situations, these agents proved to be effective.

The present review reported the methodological approaches and clinical outcomes of botanical extracts used topically for the treatment of diabetic foot ulcers in randomized controlled studies. These agents proved to be generally effective. However, many gaps existed in the study designs which may limit the evidence-based value of these studies.

One new levantilide D (2) with a 20-membered macrolide, along with one known levantilide C (1), was isolated from a rare marine actinomycetes Micromonospora sp. (FIMYZ52).

The structural elucidation of the compounds was based on integrated analyses involving 1D and 2D NMR spectroscopy and HR-ESI-MS.

The relative and absolute configurations of compounds 1 and 2 were ascertained by integrating multispectral ROESY and NOESY information from analogs in conjunction with theoretical TDDFT-ECD calculations. Levantilide D (2) exhibited antibacterial activity against Staphylococcus aureus.

A plausible biosynthetic pathway of the macrolide compounds (1-2) was proposed.