full length 16S rRNA metagenomic data of food spoilage samples and food waste digestion samples, as well as Sanger sequences of 16S gene of bacterial isolates from food waste. PacBio 16S rRNA sequencing for biofilm-augmented food waste digestion project

The treatment of discarded food waste through an aerobic digestion process using biofilm-loaded biocarriers has emerged as an attractive solution to reducing the biodegradable fraction of the solid waste burden of landfills. However, the efficiency of these biocarriers depends on the activity of the seeded microbial community structure. Here, we investigated the possibility of optimizing the biocarriers’ ability to break down cellulose-rich food waste through biofilm engineering. Six previously isolated strains from spontaneous naturally degrading fruits and vegetables, screened for their biofilm-forming ability and cellulolytic activity, were selected to enrich a biocarrier seeding microbial consortium. The food waste model used in this study was Chinese cabbage (Brassica chinensis var. oleifera), which was aerobically digested under repeated water rinsing and regular effluent drainage. The engineered biocarrier biofilm’s functionality was evaluated by tracing microbial succession with PacBio 16S rRNA metagenomic sequencing, quantitative PCR (qPCR), scanning electron microscopy (SEM) of biofilms cellulolytic activity measurement before and after digestion processes. The engineered microbial consortium demonstrated a superior biofilm-forming ability on biocarriers compared to the original microbial consortium. Engineered biofilms displayed a higher cellulolytic activity, attributed mainly to the action of selected strains used for enrichment. During the digestion process, the microbial community from both original and enriched engineered biocarrier biofilms were transferred to the vegetable surface during the first 27 hours of the operation before being colonized by the vegetables’ microflora. Following 48 hours of processing, both biofilm biocarrier consortiums ended up being flushed into the effluent. The presented study provides one of the few studies of food waste aerobic digestion, investigating the fate and functions of the microbial community of engineered biofilms seeded on biocarriers. Insights presented in this study could optimise aerobic food waste digestion to help reduce the biodegradable burden already from the source, the consumer/household level.