Unveiling microbial community structure in Ragi tape as elicitors to increase secondary metabolites contents in Glycine max and Vigna radiata

Previously, elicitation using microbe consortium inside Ragi Tape (RT) has given some insight with better results than mono-starter elicitation. However, the exact microbe species involved during elicitation remain unknown. This research aimed to identify the microbe community structure before and after elicitation using RT. Soybean (SB) and Mung Bean (MB) were used as an elicitation substrate to evaluate whether different beans affected the microbial community structure. To understand the effect of elicitation on the phytochemical profile, phytochemical content was analyzed using Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS) analysis. Fungal and bacterial species were identified using Illumina MiSeq platform and analyzed using the QIIME2 pipeline. As a result, at the species level, Saccharomycopsis fibuligera was found to be dominant fungi after elicitation occurred in both SB and MB, while Bacillus sp. and Enterobacter sp. in SB and Pantoea sp., Enterobacter sp., and Acinetobacter radioresistens in MB become the most abundant taxa from the bacterial group. Alpha diversity showed that bacteria were more abundant than fungi, while RT had greater diversity than the microbial community in post-elicitation (both SB and MB). However, beta diversity analysis revealed that both SB and MB have similar community structures. There was no significant effect of different substrates on the microbial community structure after elicitation using RT. On the other hand, the phytochemical profile was differed between the original and elicited SB and MB. In conclusion, RT has good potential as a starter of elicitation with its feasibility and availability in increasing the secondary metabolites content for general application purposes.