Enzyme-production microorganisms typically occupy a dominant position in composting, where cellulolytic microorganisms actively engage in the breakdown of lignocellulose. Exploring strains with high yields of cellulose-degrading enzymes holds substantial significance for the industrial production of related enzymes and the advancement of clean bioenergy. This study was inclined to screen cellulolytic bacteria, conduct genome analysis, mine cellulase-related genes, and optimize cellulase production. The potential carboxymethylcellulose-hydrolyzing bacterial strain Z2.6 was isolated from the maturation phase of pig manure-based compost with algae residuals as the feedstock and identified as Bacillus velezensis. In the draft genome of strain Z2.6, 31 related cellulolytic genes were annotated by the CAZy database, and further validation by cloning documented the existence of an endo-1,4-β-D-glucanase (EC 3.2.1.4) belonging to the GH5 family and a β-glucosidase (EC 3.2.1.21) belonging to the GH1 family, which are predominant types of cellulases. Through the exploration of ten factors in fermentation medium with Plackett–Burman and Box–Behnken design methodologies, maximum cellulase activity was predicted to reach 2.98 U/mL theoretically. The optimal conditions achieving this response were determined as 1.09% CMC-Na, 2.30% salinity, and 1.23% tryptone. Validation under these specified conditions yielded a cellulose activity of 3.02 U/mL, demonstrating a 3.43-fold degree of optimization. In conclusion, this comprehensive study underscored the significant capabilities of strain Z2.6 in lignocellulolytic saccharification and its potentialities for future in-depth exploration in biomass conversion.

A time series of satellite data on Chlorophyll-a concentration (Chl-a) that used ocean color was studied to determine mechanisms of phytoplankton variation in recent decade in the Yellow Sea, China during 2003–2015. The variability patterns on seasonal and inter-annual oscillation periods were confirmed using the Empirical Orthogonal Function (EOF), and Morlet wavelet transform analyses, respectively. The first EOF mode for Chl-a was dominated by obvious spring and fall blooms in a spatial pattern that was related to the strong mixing of the water masses from the Yellow Sea Cold Warm Mass (YSCWM) and the Yellow Sea Warm Current (YSWC) in winter. The second EOF mode for Chl-a showed an opposite spatial pattern between the northern and southern regions. The temporal coefficient showed differences in the timing of blooms. On an inter-annual scale, Chl-a indicated variation at periods of 2–4 years during 2003–2015. Chl-a showed a significantly negative correlation with the sea surface temperature (r = -0.21, p<0.01), with time lags of 4 months (Chl-a ahead). Chl-a was coupled with El Niño Southern Oscillation (ENSO) events, with a positive correlation (r = 0.46, p<0.01) at a lag of 3–5 months (ENSO ahead). The present study demonstrated that the variation in phytoplankton biomass was controlled primarily by water mass seasonally, and it was influenced by ENSO events on an inter-annual scale.

Lipases are widely used in food, cosmetics, detergent and the biopharmaceutics industry. Microbial lipases are typically extracellular enzymes with such advantageous properties (compared to lipases from plants or animals) as stability, versatility, and ubiquity, allowing them to perform optimally in a range of bioprocesses. Thermostability is an indispensable property for an enzyme to meet the practical requirements of industrial production. We isolated a lipase-producing strain from black pine root soil, which showed lipase activity of 11.22 U/mL. The isolate was identified as Bacillus safensis using 16S rRNA gene sequencing combined with morphological, physiological, and biochemical analyses, which showed the strain had the capability to produce lipase, urease, and decarboxylase, but did not utilize some salts and acids. Lipase cultivation conditions were optimized by single-factor experiments that included changes to temperature, pH, time, salinity, and rotational speed. The maximum lipase activity was 21.44 U/mL (191.09% higher than the initial enzyme activity) under optimized conditions of 40°C incubation, pH 7.0, 120 rpm, and 20‰ salinity for 48 h. The results of genomic analysis showed the B. safensis genome consisted of 3 747 727 bp encoding 3882 genes with 41.47% G + C content. The existence of repetitive sequences, removable genetic elements, and some secondary metabolites reflected the adaption to the adaption to live in soils in soils containing high levels of heavy metals and salt and the ability to endure extreme conditions, such as high temperatures. The study demonstrated that B. safensis is a source of lipase with potential application in numerous biotechnological industries.