This study isolated endophytic fungi of the genus Nigrospora from Aquilaria sinensis (Chinese agarwood) in Guangxi, China. Through rigorous morphological comparisons and molecular phylogenetic analyses, we have identified two new species (N. guangxiensis and N. pubeiensis) and two new host-recorded species (N. oryzae and N. camelliae-sinensis). The morphological analysis revealed that the new species align with the genus-level definition of Nigrospora in colony morphology, conidiophores, and conidial characteristics. However, they were distinguished from known species by finer features such as conidial dimensions and conidiogenous structures. For instance, conidiophores in Nigrospora are typically differentiated from hyphae, characterized by dark pigmentation, which is consistent with broader taxonomic descriptions. Molecular phylogeny, based on concatenated datasets of the ITS, TEF1-α, and TUB2 loci, showed that N. pubeiensis is most closely related to N. chinensis, while N. guangxiensis forms a distinct basal clade relative to these two groups. Additionally, N. oryzae and N. camelliae-sinensis were first recorded on A. sinensis, expanding their known host ranges. The study enriches the taxonomic framework of Nigrospora by providing novel data from China, emphasizing the importance of integrating morphological and molecular approaches in fungal systematics. It also underscores the ecological diversity of fungal-host interactions in agarwood-producing trees, a topic explored in related research on endophytic fungi. These findings have significant implications for our understanding of fungal diversity and their ecological roles in agarwood-producing trees, and they pave the way for further research in this area.
Tag: agarwood
Volatile Constituents of Endophytic Fungi Isolated from Aquilaria sinensis with Descriptions of Two New Species of Nemania
Algae, bacteria, and fungi, as well as higher plants, produce a wide variety of secondary metabolites known as natural products. Natural products are well known as remarkable sources of many therapeutic agents. The genus Nemania is a wood-decaying fungus that belongs to family Xylariaceae. Nemania is often found as an endophyte in diverse hosts and some species are known to produce useful secondary metabolites. In this study, two Nemania species were isolated as an endophytic fungus from Aquilaria sinensis. Multi-gene phylogenetic studies showed that the newly described strains of Nemania are new to science, and this is the first report of Nemania from the host Aquilaria. One of the fermented species, Nemania aquilariae (KUMCC 20-0268), resulted in five sesquiterpenoids, which were previously reported from agarwood, and their structures were identified by gas chromatography-mass spectrometry (GC-MS). In addition, five different media were investigated in vitro to optimize conditions for growing the fungal biomass of Nemania aquilariae and N. yunnanensis.