Temporal Dynamics of Bacterial Communities in a Pilot-Scale Vermireactor Fed with Distilled Grape Marc

Abstract

Vermicomposting has been found as a profitable approach to dispose of and treat large quantities of raw grape marc. However, less information is available with regard to its efficiency for treating distillery winery byproducts, even though distillation has been widely used as a way to economically valorize grape marc. As such, we sought to characterize the compositional and functional changes in bacterial communities during vermicomposting of distilled grape marc by using 16S rRNA high-throughput sequencing. Samples were collected at the initiation of vermicomposting and at days 14, 21, 28, 35 and 42. There were significant changes (p < 0.0001) in the bacterial community composition of distilled grape marc after 14 days of vermicomposting that were accompanied by twofold increases in bacterial richness and diversity from a taxonomic and phylogenetic perspective. This was followed by significant increases in functional diversity of the bacterial community, including metabolic capacity, lignin and cellulose metabolism, and salicylic acid synthesis. These findings indicate that the most striking compositional and functional bacterial community changes took place during the active phase of the process. They also pinpoint functional attributes that may be related to the potential beneficial effects of distilled grape marc vermicompost when applied on soil and plants.

Recycling and valorization of distilled grape marc through vermicomposting: a pilot-scale study

“…The clear separation between days 0 and 14 provides further evidence about how quickly vermicomposting modulated the physico-chemical, chemical and biological properties of the Mencía distilled marc within the first two weeks of vermicomposting. This goes hand in hand with the rapid compositional and functional changes reported by Gómez-Brandón et al [14,24] and Kolbe et al [13] on raw and distilled grape marc´s bacterial communities during the first stages of the process on a pilot-scale level. Gómez-Brandón et al [19] also found, on a mesocosm scale, that earthworms' activity (Eisenia andrei) promoted the stabilization of grape marc after only two weeks of vermicomposting.…”

“…The plausible differences between the raw and distilled marcs' initial composition are expected to distinctly affect the dynamics of the vermicomposting process and in turn, the properties of the final vermicompost. Indeed, Gómez-Brandón et al [24] found that distilled grape marc-derived vermicompost was characterized by a reduced bacterial communities' functional diversity, assessed as a proxy of their metabolic capacity when compared to the respective raw marc [13]. Taken together, this highlights the clear need for more comprehensive studies on distilled grape marc to further evaluate the effectiveness of vermicomposting for the biological stabilization of this winery by-product on a pilot-scale level given the limited evidence to date in comparison with raw marc [23][24][25][26] (Table 1).…”

Vermicomposting as a Valorization Solution to the Winery Sector By-Products

“…The authors concluded that, although bacteria and fungi are the main agents behind biochemical decomposition, earthworms play an essential role in vermicomposting, as evidenced by their ability to accelerate decomposition and significantly modify the physical and microbiological properties of the substrate [114]. Furthermore, Gómez Brandón et al [117] treated distilled grape marc through vermicomposting over 42 days, and the results showed significant changes in the bacterial community, accompanied by a two-fold increase in bacterial richness and diversity, both taxonomically and phylogenetically.…”

Distinctive microbial community and genome structure in coastal seawater from a human-made port and nearby offshore island in northern Taiwan facing the Northwestern Pacific Ocean

“…Saccharimonadaceae was found to be more abundant in colorectal cancer (CRC) model mice when chromium was administered [72]. Saccharimonadaceae is also an intestinal metabolizer and microbial degrader in earthworms [73,74].…”