11 research outputs found
Fig 4 -
Relative abundances of bacterial communities at the phylum (a) and genus (b) level of the inoculum, WW (water washing), and CS (chemical soaking). Taxa with abundances <1% of the total sequences in the samples were grouped as other.</p
A summary of the results of the biomethane potential test of untreated and pretreated <i>Sargassum</i> spp. after 70 days of incubation and 53 days for cellulose.
A summary of the results of the biomethane potential test of untreated and pretreated Sargassum spp. after 70 days of incubation and 53 days for cellulose.</p
S1 Data -
Sargassum spp. flood the Caribbean coastline, causing damage to the local economy and environment. Anaerobic digestion (AD) has been proposed as an attractive option for turning macroalgae into valuable resources. Sargassum spp. has a complex composition that affects the microbial composition involved in AD which generates a low methane yield. This study aimed to improve the methane yield of pelagic Sargassum, using different energy-saving pretreatments and identifying the microbial community associated with methane production. We applied different energy-saving pretreatments to algal biomass and assessed the methane yield using a biomethane potential (BMP) test. The microbial communities involved in the AD of the best- and worst-performing methanogenic systems were analyzed by high-throughput sequencing. The results showed that pretreatment modified the content of inorganic compounds, fibers, and the C:N ratio, which had a strong positive correlation with BMP. The water washing pretreatment resulted in the best methane yield, with an increase of 38%. DNA metabarcoding analysis revealed that the bacterial genera Marinilabiliaceae_uncultured, DMER64, Treponema, and Hydrogenispora, as well as the archaea genera Methanosarcina, RumEn_M2, Bathyarchaeia, and Methanomassiliicocus, dominated the microbial community with a high methane yield. This study is the first to demonstrate the microbial community structure involved in the AD of Sargassum spp. The pretreatments presented in this study can help overcome the limitations associated with methane yield.</div
Heat map of Spearman’s correlation analysis between the compositional characteristics of <i>Sargassum</i> spp. and BMP/BI.
Cel = Cellulose; Hcel = Hemicellulose; Lig = Lignin; TPC = Total phenolic content. The mark * indicates the significance test (p <0.05).</p
Alpha-diversity indices of the different microbial communities.
Alpha-diversity indices of the different microbial communities.</p
Fig 5 -
Relative abundances of archaeal communities at the phylum (a) and genus (b) level of the inoculum, WW (water washing), and CS (chemical soaking). Taxa with abundances <2% of the total sequences in the samples were grouped as other.</p
Cumulative methane production expressed in N mL·g<sup>-1</sup> VS of pretreated and untreated <i>Sargassum</i> spp. biomass after 70 days of incubation.
UT = Untreated, WW = Water washing, S+W = Soaking + Warm water washing, CS = Chemical soaking. Error bars represent the standard deviation of the mean (n = 3).</p
Changes in the compositional characteristics (% dry weight) of <i>Sargassum</i> spp. by the effect of pretreatments.
UT = Untreated, WW = Water washing, S+W = Soaking + Warm water washing, CS = Chemical soaking.</p
Influence of pretreatments on the content of mineral salts and total removal in the biomass of <i>Sargassum</i> spp. UT = Untreated, WW = Water washing, S+W = Soaking + Warm water washing, CS = Chemical soaking.
Influence of pretreatments on the content of mineral salts and total removal in the biomass of Sargassum spp. UT = Untreated, WW = Water washing, S+W = Soaking + Warm water washing, CS = Chemical soaking.</p
S2 Data -
Sargassum spp. flood the Caribbean coastline, causing damage to the local economy and environment. Anaerobic digestion (AD) has been proposed as an attractive option for turning macroalgae into valuable resources. Sargassum spp. has a complex composition that affects the microbial composition involved in AD which generates a low methane yield. This study aimed to improve the methane yield of pelagic Sargassum, using different energy-saving pretreatments and identifying the microbial community associated with methane production. We applied different energy-saving pretreatments to algal biomass and assessed the methane yield using a biomethane potential (BMP) test. The microbial communities involved in the AD of the best- and worst-performing methanogenic systems were analyzed by high-throughput sequencing. The results showed that pretreatment modified the content of inorganic compounds, fibers, and the C:N ratio, which had a strong positive correlation with BMP. The water washing pretreatment resulted in the best methane yield, with an increase of 38%. DNA metabarcoding analysis revealed that the bacterial genera Marinilabiliaceae_uncultured, DMER64, Treponema, and Hydrogenispora, as well as the archaea genera Methanosarcina, RumEn_M2, Bathyarchaeia, and Methanomassiliicocus, dominated the microbial community with a high methane yield. This study is the first to demonstrate the microbial community structure involved in the AD of Sargassum spp. The pretreatments presented in this study can help overcome the limitations associated with methane yield.</div