Cellulase and xylanase activity during the decomposition of three aquatic macrophytes in a tropical oxbow lagoon

Abstract

Due to the connection between enzymatic activity and degradation of different fractions of organic matter, enzyme assays can be used to estimate degradation rates of particulate and dissolved organic carbon in freshwater systems. The aim of this study was to quantify and model the enzymatic degradation involving the decomposition of macrophytes, describing temporal activity of cellulases (EC 3.2.1.4 and EC 3.2.1.91) and xylanase (EC 3.2.1.8) during in situ decomposition of three aquatic macrophytes (Salvinia sp., Eichhornia azurea and Cyperus giganteus) on the surface and water-sediment interface (w-s interface) of an oxbow lagoon (Óleo lagoon) within a natural Brazilian Savanna Reserve. Overall, the enzymatic degradation of aquatic macrophytes in Óleo lagoon occurred during the whole year and was initiated together with leaching. Xylanase production was ca. 5 times higher than cellulase values due to easy access to this compound by cellulolytic microorganisms. Enzymatic production and detritus mass decay were similar on the surface and w-s interface. Salvinia sp. was the most recalcitrant detritus, with low mass decay and enzymatic activity. E. azurea and C. giganteus decomposition rates and enzymatic production were high and similar. Due to the physicochemical homogeneity observed in the Óleo lagoon, the differences between the decay rates of each species are mostly related with detritus chemical quality.

The phosphorus release pathways and their mechanisms driven by organic carbon and nitrogen in sediments of eutrophic shallow lakes

“…Thus far, the studies on extracellular enzymes activities (EEA) have been mainly associated with organic matter degradation by microbes (Teske et al, 2011;Alvarez and Guerrero, 2000;Hiroki et al, 2007) and nutrient limitation (Hill et al, 2012;Hill et al, 2010). Furthermore, EEA was also used to reflect the different trophic status of shallow lakes (Caruso et al, 2005;Kalwasinska and Brzezinska, 2013;Ziervogel et al, 2014) and estimate degradation rates (Jackson et al, 1995;Alvarez and Guerrero, 2000;Sciessere et al, 2011) and turnover times (Misic and Harriague, 2009) of organic matter. In the process of organic matter decomposition, N90% of the biologically consumed O 2 in the biosphere can be occurred (Packard, 1985), which further influenced the electron transport system.…”

Long‐term straw mulching in a no‐till field improves soil functionality and rice yield by increasing soil enzymatic activity and chemical properties in paddy soils

“…Cellulase enzyme activity was significantly and often dramatically increased in CTP soils. Cellulase is an important enzyme involved in the initial phase of the decomposition of organic C compounds (Sciessere et al., 2011), and fungi are the major source of this enzyme in soil (Bonini Pires et al., 2020). Overall, our findings are consistent with prior studies where CTP treatments, including a reduction in tillage intensity, led to improved soil organic matter content and increased microbial biomass (Pandey et al., 2014).…”

Enzymatic efficiency of the decomposing microbiota: what does really matter for aquatic macrophytes invasions?

“…Despite the greater complexity of hemicellulose, with short side chains of different sugars (e.g., D-xylose, D-mannose, D-galactose, D-glucose, L-arabinose, acid 4-O-methyl-glucourônico, D-galactourôrico, and D-glucourônico) (Pérez et al 2002), which entails the need for a greater diversity of hydrolysing enzymes, which presents binding sites that are more accessible than cellulose (Gilbert & Hazlewood 1993) without forming aggregates, even when co-crystallized with cellulose chains (Cunha-Santino & Bianchini Jr. 2008). Sciessere et al (2011) and Nunes et al (2011) considered the higher xylanase activity observed in litters of Salvinia sp., Eichhornia azurea, Cyperus giganteus, Ricciocarpus natans, Oxycaryum cubense, and Cabomba furcata because of the easy access of this fibre for the microorganisms when compared with cellulose access.…”