Gene cloning of phenolic acid decarboxylase from Bacillus subtilis and expression in top-fermenting yeast strain

Phenolic acid decarboxylase (PADC) gene, encoding phenolic acid decarboxylase, was cloned from Bacillus subtilis and ligated with a shuttle vector YEp352 to generate a novel plasmid YPADC. By analysis of sequencing and the restriction endonuclease digestion, the validity of construction was proved. Subsequently, the new vector was successfully transformed into wild-type top-fermenting yeast strain W303-1A; the mutant yeast strain W303+padc was obtained, which was tested on the laboratoryscale mashing and fermentation experiments. At the end of fermentation, the results showed an obvious increase of 4-vinylguaiacol content in top-fermented beers brewed with mutant yeasts. The final 4-vinylguaiacol concentration obtained with wild-type and mutant yeasts was 1.20 and 1.70mg/l, respectively. Additionally, the level of esters produced by the mutant strain was higher than that of the wild-type; there were therefore a marked clove-like and ester aroma in top-fermented beers brewed with the former. However, no evident differences were found in brewing characteristic between wild-type and mutant strains, especially the ability of utilizing fermentable sugar and reducing diacetyl. Taken together, these approaches indicated the possibility of cloning PADC gene and enhancing the concentration of 4-vinylguaiacol in top-fermented beers.size.Keywords: Clone, phenolic acid decarboxylase, top-fermenting yeast, 4-vinylguaiacolAfrican Journal of Biotechnology Vol. 9(33), pp. 5284-5291, 16 August, 201

Bacillus amyloliquefaciens Ameliorates Dextran Sulfate Sodium-Induced Colitis by Improving Gut Microbial Dysbiosis in Mice Model

Several Bacillus strains exert beneficial effects on the maintenance of intestinal homeostasis and host health. However, whether Bacillus amyloliquefaciens (BA) can improve gut microbial dysbiosis and ameliorate colitis is unknown. Therefore, we conducted the present study to investigate the effects of BA administration on intestinal morphology, inflammatory response, and colonic microbial composition in a mouse model of dextran sulfate sodium (DSS)-induced colitis. Results showed that BA administration significantly ameliorated body weight loss, decreased disease activity index, and improved colonic tissue morphology in DSS-treated mice. In addition, levels of immunoglobulins, as well as pro-inflammatory cytokines, were decreased after BA administration. Importantly, colonic microbiota profiling indicated a significant (p < 0.05) difference in beta-diversity between BA-administrated and DSS-treated mice, according to weighted principal coordinate analysis (PCoA) results. The relative abundance of the Firmicutes genus was increased, whereas that of Bacteroidetes was decreased by BA administration. Furthermore, phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) analysis showed that the most significantly changed pathways between the four groups of mice were carbohydrate, lipid, and amino acid metabolism. In conclusion, our results showed that BA administration has beneficial effects on DSS-induced colitis, suggesting that this strategy might be useful for the treatment of dysbiosis during ulcerative colitis. Further, the changes in metabolism, especially amino acid metabolism, might contribute to the beneficial effects of BA on the amelioration of DSS-induced colitis

Research on Key Technical Indexes of Coastal Reclamation Planning and Design

Large-scale coastal reclamation has become a significant land use issue worldwide for urban construction and economic development. The reclamation of coastal wetlands brings substantial economic benefits, however, the structure and function of coastal ecosystem are affected by drivers of human-caused landscape change. This research takes Hangzhou Bay and Zhoushan Islands as the case study to investigate the correlation between the coastal geomorphic complexity and the tidal range reduction rate, and to explore the control technical indexes of the design in reclamation area by a multidisciplinary approach that integrates the basic theories and quantitative methods of fractal geometry with the hydrodynamic mechanism of ocean dynamics. The results show that the coastal tidal range reduction rate is closely related to the coastline fractal dimension and patch shape index (D, S), and reveals the influence of the complexity of the coastal landscape on the tidal energy loss. In addition, based on model predictions, it can be found that the large-scale reclamation in Zhoushan will cause a serious decline in the complexity of the coastal landscape and the reduction of tidal energy, which is extremely detrimental to coastal disaster prevention. In the end, the scientific design theory and quantitative control indexes of reclamation are put forward to provide theoretical basis and design reference for future coastal reclamation and disaster prevention

Multi scale characteristics of Antarctic temperature change in January from 1982 to 2020

Antarctica is a sensitive area of global temperature change. Analyzing the temperature change in Antarctica can provide a basis for the analysis of global climate change The shared data provided by the automatic weather station plan are analyzed, and the relatively complete January temperature of Antarctic 8905 station from 1981 to 2020 is selected for analysis. Using the multi-scale analysis function of wavelet analysis, Morlet wavelet function is selected to carry out continuous wavelet transform on the daily temperature data, and the real part, modulus square and variance of continuous wavelet change are analyzed. It is found that the daily temperature of Antarctica is There are 14, 27, 72, 268, 380 and 665 day main periods for temperature changes. The trend analysis of wavelet transform coefficients under each period shows that the Antarctic temperature is in a high temperature period of 14, 27, 72, 268, 380 and 665 day periods in the years after 2021. The maximum temperature in January in Antarctica has a 20-year main period, and the minimum temperature has a 14-year and 23-year main period, The average value has a main cycle of 6 years, 14 years and 24 years

Frequency analysis of representative flood control water level stations in Puyang River

Puyang river basin is located in the north central part of Zhejiang Province, which is one of the most important river basins in Zhejiang Province. The lower reaches of Puyang River are easily influenced by tide in Hangzhou Bay and flood in Qiantang River. When Puyang river floods, it often meets Fuchun River and floods occur at the same time. The flood discharge of Puyang river is blocked and the water level rises and rises, which makes the Puyang River vulnerable to disaster. Water level frequency analysis is the basis of Puyang river planning and flood control plan. The representative flood control water level stations of Puyang River include Zhuji station and wenjiayan station. The frequency analysis of these representative stations is helpful to determine the water level of these key nodes under different frequencies, and to provide basic data for accurate flood control of Puyang River and ensure the safety of flood control

Dietary bamboo leaf flavonoids improve quality and microstructure of broiler meat by changing untargeted metabolome

Abstract Background Dietary bamboo leaf flavonoids (BLFs) are rarely used in poultry production, and it is unknown whether they influence meat texture profile, perceived color, or microstructure. Results A total of 720 one-day-old Arbor Acres broilers were supplemented with a basal diet with 20 mg bacitracin/kg, 50 mg BLFs/kg, or 250 mg BLFs/kg or without additions. Data showed that the dietary BLFs significantly (P < 0.05) changed growth performance and the texture profile. In particular, BLFs increased birds’ average daily gain and average daily feed intake, decreased the feed:gain ratio and mortality rate, improved elasticity of breast meat, enhanced the gumminess of breast and leg meat, and decreased the hardness of breast meat. Moreover, a significant (P < 0.05) increase in redness (a*) and chroma (c*) of breast meat and c* and water-holding capacity of leg meat was found in BLF-supplemented broilers compared with control broilers. In addition, BLFs supplementation significantly decreased (P < 0.05) the β-sheet ratio and serum malondialdehyde and increased the β-turn ratio of protein secondary structure, superoxide dismutase, and glutathione peroxidase of breast meat and total antioxidant capacity and catalase of serum. Based on the analysis of untargeted metabolome, BLFs treatment considerably altered 14 metabolites of the breast meat, including flavonoids, amino acids, and organic acids, as well as phenolic and aromatic compounds. Conclusions Dietary BLFs supplementation could play a beneficial role in improving meat quality and sensory color in the poultry industry by changing protein secondary structures and modulating metabolites