Diversity and antimicrobial potential of the culturable rhizobacteria from medicinal plant Baccharis trimera Less D.C

• Published in: Brazilian journal of microbiology Vol. 53; no. 3; pp. 1409 - 1424
• Main Authors: Jardim, Ana Camila Munis, de Oliveira, Jéssica Ellen, Alves, Luana de Moura, Gutuzzo, Giovana Oliveira, de Oliveira, André Luiz Martinez, Rodrigues, Elisete Pains
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-09-2022; Springer Nature B.V
• Subjects: Anti-Bacterial Agents - metabolism; Anti-Bacterial Agents - pharmacology; Antifungal activity; Antifungal Agents - metabolism; Antifungal Agents - pharmacology; Antiinfectives and antibacterials; Antimicrobial agents; Baccharis; Baccharis - metabolism; Bacteria; Biomedical and Life Sciences; Biosurfactants; Environmental Microbiology - Research Paper; Food Microbiology; Fungicides; Herbal medicine; Humans; Indigenous plants; Life Sciences; Medical Microbiology; Medicinal plants; Metabolites; Microbial Ecology; Microbial Genetics and Genomics; Microbiology; Microbiota; Mycology; Plant bacterial diseases; Plant growth; Plant Roots - microbiology; Plants, Medicinal; Rhizosphere; rRNA 16S; Secondary metabolites; Siderophores; Siderophores - metabolism; Species; Species diversity; Streptomyces; Surfactants; Biosurfactant; Microbiota; Endophytic bacteria; Siderophore; Carqueja
• ISSN: 1517-8382; 1678-4405
• DOI: 10.1007/s42770-022-00759-5

Plant microbiota is usually enriched with bacteria producers of secondary metabolites and represents a valuable source of novel species and compounds. Here, we analyzed the diversity of culturable root-associated bacteria of the medicinal native plant
Baccharis trimera
(Carqueja) and screened promising isolates for their antimicrobial properties. The rhizobacteria were isolated from the endosphere and rhizosphere of
B. trimera
from Ponta Grossa and Ortigueira localities and identified by sequencing and restriction analysis of the 16S rDNA. The most promising isolates were screened for antifungal activities and the production of siderophores and biosurfactants.
B. trimera
presented a diverse community of rhizobacteria, constituted of 26 families and 41 genera, with a predominance of
Streptomyces
and
Bacillus
genera, followed by
Paenibacillus
,
Staphylococcus
,
Methylobacterium
,
Rhizobium
,
Tardiphaga
,
Paraburkholderia
,
Burkholderia
, and
Pseudomonas
. The more abundant genera were represented by different species, showing a high diversity of the microbiota associated to
B. trimera
. Some of these isolates potentially represent novel species and deserve further examination. The communities were influenced by both the edaphic properties of the sampling locations and the plant niches. Approximately one-third of the rhizobacteria exhibited antifungal activity against
Sclerotinia sclerotiorum
and
Colletotrichum gloeosporioides
, and a high proportion of isolates produced siderophores (25%) and biosurfactants (42%). The most promising isolates were members of the
Streptomyces
genus. The survey of
B. trimera
returned a diverse community of culturable rhizobacteria and identified potential candidates for the development of plant growth-promoting and protection products, reinforcing the need for more comprehensive investigations of the microbiota of Brazilian native plants and habitats.