Screening of Endophytic Bacteria of Leucojum aestivum ‘Gravety Giant’ as a Potential Source of Alkaloids and as Antagonist to Some Plant Fungal Pathogens

Abstract

Leucojum aestivum is a medicinal plant belonging to the Amaryllidaceae family well known as a producer of alkaloids such as galanthamine and lycorine. However, the endophytic microbes that colonize different plant tissues without causing any damage have not been reported in this plant. Here, we explored the different endophytic bacterial communities isolated from different surface disinfected tissues of L. aestivum ‘Gravety giant’ and screened bacterial isolates producing alkaloids and their potential use as biocontrol agent against wheat pathogens. For that purpose, endophytic bacteria were isolated from bulbs, roots and shoots of L. aestivum. After taxonomical characterization, these microorganisms were screened for their ability to produce alkaloids using high-performance thin-layer chromatography (HPTLC) and untargeted liquid chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS) strategies. We isolated 138 bacteria belonging to four phyla and 42 genera, mainly from roots and shoots. The most abundant genera were Rahnella in shoot, Patulibacter in bulb and Bacillus in roots. Among the different bacterial isolates, the methanolic extracts of Luteibacter rhizovicinus (LaBFB3301) and Commamonas denitrificans (LaBFS2103) slightly delayed the growth of F. graminearum colonies in in vitro dual tests against F. graminearum and M. nivale strains with 15.5% and 19.9% inhibition rates, respectively. These isolates are able to produce an indolic alkaloid tryptophol (C10H11NO, [M + H]+ 162.0913). These endophytic bacteria might be investigated to characterize the plant protection effect and the plant growth promotion effect.

Isolation and characterization of endophytic bacteria from sterile leaf of Acrostichum aureum from Bengkalis Island (Riau, Indonesia) and its potency for antidiabetic

“…All the isolates showed the presence of alkaloids (Figure 5A1-5A7). The presence of alkaloids in bacteria has also been reported in previous studies by Purwestri et al (2016), Munakata et al (2022), andPtak et al (2022). Alkaloid is a nitrogen base compound that poses numerous health benefits.…”

Bioactivity potential and chemical profile of endophytic Stutzerimonas stutzeri strain D2 isolated from Myristica fatua Houtt

“…More bacterial endophyte isolates found in roots indicate that roots provide a more favorable environment for bacterial colonization. Earlier studies also reported that the number of endophytic bacteria in roots of Leucojum aestivum [14], Lactuca indica [15], and Targetes sp. [16], was higher than aerial plant parts.…”

The screening for marine fungal strains with high potential in alkaloids production by in situ colony assay and LC-MS/MS based secondary metabolic profiling

“…The traditional screening of alkaloid-producing strains is usually carried out via alkaloids detecting in culture extracts by chromogenic reactions in liquid or on TLC plate and by HPLC, LC-MS, or direct ESI-MS ( Yin and Sun, 2011 ; Han et al, 2015 ; da Silva et al, 2021 ; Munakata et al, 2022 ). However, these methods usually require a term of fermentation before extraction of metabolites from all the tested strains in the first step.…”

“…However, in situ colony screening of alkaloidproducing strains has not been reported. The traditional screening of alkaloid-producing strains is performed by fermentation of all the tested strains, metabolites extraction, preliminary thin-layer chromatographic (TLC) colorization analysis using dyes like Dragendorff reagent, and in-depth diversity analysis using high performance liquid chromatography (HPLC), liquid chromatography-mass spectrometry (LC-MS), or direct compound isolation and structural elucidation (Yin and Sun, 2011;Han et al, 2015;Munakata et al, 2022). This pipeline is laborious, time-consuming, long-period, and unpredictable to the structural information.…”