Development of autochthonous starter for cigar fermentation dissecting the microbiome.

INTRODUCTION

The main goal of tobacco fermentation technology is to minimize the alkaloid content while improving flavor substance content.

METHODS

This study revealed the microbial community structure and their metabolic functions during cigar leaf fermentation by high-throughput sequencing and correlation analysis, and evaluated the fermentation performance of functional microbes based on in vitro isolation and bioaugmentation fermentation.

RESULTS

The relative abundance of and increased first but then decreased during the fermentation, and would occupy the dominant position of bacterial and fungal communities, respectively, on the 21st day. Correlation analysis predicted that , and could contribute to the formation of saccharide compounds, might have degradation effects on nitrogenous substances. In particular, , as a co-occurring taxa and biomarker in the later stage of fermentation, could not only degrade nitrogenous substrates and synthesize flavor substances, but also contribute to maintaining the stability of microbial community. Moreover, based on isolation and bioaugmentation inoculation, it was found that and could significantly reduce the alkaloids content and increase the content of flavor components in tobacco leaves.

DISCUSSION

This study found and validated the critical role of in the fermentation of cigar tobacco leaves through high-throughput sequencing and bioaugmentation inoculation, which would help guide the development of microbial starters and directional regulation of cigar tobacco quality.