Rhizobacteria as agents to enhance high value natural products
in plants
Beyond assessing the co-occurrence of specific metabolites associated
with growth promotion in different plant-bacteria interactions, our
result also revealed that the three different rhizobacterial genera can
boost nutritionally and/or pharmaceutically important high value natural
plant compounds (HVPC). The list of various putative HVPC are summarized
in Supplementary Table S9 . Among these, flavonoid glycosides
induced in the ineffective partnership between Pbg and
Arabidopsis are considered vital phytochemicals in diets and are of
great interest due to their diverse bioactivities (Xiao et al.2016). Similarly, glucosinolates in Brassica species (Traka 2016),
hydroxycinnamic acid derivatives (Alam et al. 2016) and
dihydroartemisinin in Artemisia (Tilley et al. 2016) are
potential HPVC. In effective partnerships, the increase in these
compounds is even more pronounced when we consider the increase in host
biomass due to rhizobacteria inoculation. A typical example for this is
the Pbg -Artemisia combination that resulted in five-fold increase
in host biomass and up to three-fold increase in both artemisinic
alcohol and dihydroartemisinin per unit fresh tissue biomass. Hence, the
use of rhizobacteria may be considered as a simple and generic approach
to boost economically or pharmaceutically interesting plant metabolites.