Antimicrobial fungal endophytes from the botanical medicine goldenseal ( Hydrastis canadensis )

Abstract

The potential of fungal endophytes to alter or contribute to plant chemistry and biology has been the topic of a great deal of recent interest. For plants that are used medicinally, it has been proposed that endophytes might play an important role in biological activity. With this study, we sought to identify antimicrobial fungal endophytes from the medicinal plant goldenseal (Hydrastis canadensis L., Ranunculaceae), a plant used in traditional medicine to treat infection. A total of 23 fungal cultures were obtained from surface-sterilized samples of H. canadensis roots, leaves and seeds. Eleven secondary metabolites were isolated from these fungal endophytes, five of which had reported antimicrobial activity. Hydrastis canadensis plant material was then analyzed for the presence of fungal metabolites using liquid chromatography coupled to high resolving power mass spectrometry. The antimicrobial compound alternariol monomethyl ether was detected both as a metabolite of the fungal endophyte Alternaria spp. isolated from H. canadensis seeds, and as a component of an extract from the H. canadensis seed material. Notably, fungi of the Alternaria genus were isolated from three separate accessions of H. canadensis plant material collected in a time period spanning 5 years. The concentration of alternariol monomethyl ether (991 mg/kg in dry seed material) was in a similar range to that previously reported for metabolites of ecologically important fungal endophytes. The seed extracts themselves, however, did not possess antimicrobial activity.

Core Microbiome of Medicinal Plant Salvia miltiorrhiza Seed: A Rich Reservoir of Beneficial Microbes for Secondary Metabolism?

“…Therefore, the genera Pseudomonas and Sphingomonas in the seed microbiome are likely to be important reservoirs of rhizosphere or endosphere microbiome. Regarding the shared fungal core taxa, genus Alternaria can be a potential plant pathogen, but it also includes beneficial endophytes as biocontrol agents or other active compounds producing microbes [ 49 , 50 , 51 , 52 ]. Therefore, Alternaria can affect the germination of seeds and the assemblage of plant microbiome, and consequently, the growth and fitness of plants.…”

Compositional analysis, biological activity, and food protecting ability of ethanolic extract ofQuercus infectoriagall

“…Deteriorative effects of sorbate and benzoate on mitochondrial permeability may result in Reye’s syndrome, elevated reactive oxygen species(ROS) production, and mitochondrial damages ( Piper & Piper, 2017 ) . Much effort was devoted to the investigation of botanical antimicrobials due to health concerns and public sensitivity against the use of synthetic chemicals in the processed foods ( Dimkić et al., 2016; Egan et al., 2016 ) . The use of natural preservatives to protect the food against microbial spoilage is preferential over synthetic chemicals, especially when we consider children or elderly people’s diet.…”

High yield accelerated reactions in nonvolatile microthin films: chemical derivatization for analysis of single-cell intracellular fluid

“…Chemical derivatization is an important strategy to increase analytical performance, 1 – 5 especially analytical sensitivity and selectivity, 6 , 7 and it has been widely used for profiling metabolites, 8 , 9 quantifying bioactive small molecules and identifying natural products. 10 – 12 Recently, new demands have been placed on chemical derivatization in the analysis of small amounts of compounds in microvolume samples derived from individual cells. 13 Especially significant on very small scales is the fact that derivatization can lead to loss of analytes due to unsatisfactory reaction yields.…”

“…To characterize the performance of such a microthin film reactor, the Schiff base reaction between a set of primary amines and saccharides ( Scheme 1 ) was studied and the data are compared to bulk reactions run under traditional bulk, neat, and paste conditions. The reasons for this particular choice are (i) Schiff base formation is a reversible reaction with a modest equilibrium constant 34 , 35 and a reaction rate constant which makes it very difficult to perform chemical derivatization in small volume samples, (ii) identification and quantification of bioactive molecules like saccharides in tissues and single cells is an important task which could lead to deeper understanding of metabolic pathways, 8 , 9 cell heterogeneity 36 – 40 and even to the discovery of new drugs 10 – 12 and (iii) imine formation is an attractive route to efficient ionization of sugars.…”