Optimization of growth media components for polyhydroxyalkanoate (PHA) production from organic acids by Ralstonia eutropha

We employed systematic mixture analysis to determine optimal levels of acetate, propionate, and butyrate for cell growth and polyhydroxyalkanoate (PHA) production by Ralstonia eutropha H16. Butyrate was the preferred acid for robust cell growth and high PHA production. The 3-hydroxyvalerate content in the resulting PHA depended on the proportion of propionate initially present in the growth medium. The proportion of acetate dramatically affected the final pH of the growth medium. A model was constructed using our data that predicts the effects of these acids, individually and in combination, on cell dry weight (CDW), PHA content (%CDW), PHA production, 3HV in the polymer, and final culture pH. Cell growth and PHA production improved approximately 1.5-fold over initial conditions when the proportion of butyrate was increased. Optimization of the phosphate buffer content in medium containing higher amounts of butyrate improved cell growth and PHA production more than 4-fold. The validated organic acid mixture analysis model can be used to optimize R. eutropha culture conditions, in order to meet targets for PHA production and/or polymer HV content. By modifying the growth medium made from treated industrial waste, such as palm oil mill effluent, more PHA can be produced.Malaysia. Ministry of Science, Technology and Innovation (MOSTI

Genomic landscape of lung adenocarcinoma in East Asians

Lung cancer is the world’s leading cause of cancer death and shows strong ancestry disparities. By sequencing and assembling a large genomic and transcriptomic dataset of lung adenocarcinoma (LUAD) in individuals of East Asian ancestry (EAS; n = 305), we found that East Asian LUADs had more stable genomes characterized by fewer mutations and fewer copy number alterations than LUADs from individuals of European ancestry. This difference is much stronger in smokers as compared to nonsmokers. Transcriptomic clustering identified a new EAS-specific LUAD subgroup with a less complex genomic profile and upregulated immune-related genes, allowing the possibility of immunotherapy-based approaches. Integrative analysis across clinical and molecular features showed the importance of molecular phenotypes in patient prognostic stratification. EAS LUADs had better prediction accuracy than those of European ancestry, potentially due to their less complex genomic architecture. This study elucidated a comprehensive genomic landscape of EAS LUADs and highlighted important ancestry differences between the two cohorts

Drying And Extraction of Moringa Oleifera And Its Application In Wastewater Treatment

Abstract Conventional coagulants such as aluminum sulfate and ferric sulphate have proved to be harmful to human health as it may cause neurological diseases like Alzheimer and percentile dementia. These health concerns have led to the use of natural coagulants which are environmental friendly and not harmful to human health. In this study, Moringa Oleifera seeds are selected to study the preparation of the natural coagulant and further use it in dye wastewater treatment. The two important steps used in preparing the natural coagulants are drying of the raw materials and extraction of the protein content. Moringa Oleifera seeds were oven dried at 40°C, 50°C and 60°C and the drying data was recorded. The recorded data was then fitted into five thin layer kinetic models to obtain the most suitable drying temperature and its corresponding drying time. Using Microsoft Excel Solver 2011, values of (R2), (RMSE) and chi-square (X2 ) were calculated. Based on the highest value of (R2 ) and lowest value of (RMSE), Page kinetic model was selected. Moreover, for the selected Page kinetic model, values of (R2) and (X2) were also compared for all three temperatures and the temperature with the highest (R2) value and lowest chi-square value (X2) was selected as the most optimum drying temperature. The most optimum drying temperature for drying Moringa Oleifera seeds was obtained as 50°C as the seeds dried at this temperature holds the maximum protein content concentration which enhances its coagulation properties. Furthermore, the corresponding drying time of about 6.5 hours for seeds dried at 50°C was also taken as the most optimum drying time. In the next step, Moringa Oleifera seeds which have been dried at 50°C for 6.5 hours were used for protein extraction. Solid to solvent ratios of 0.5:100, 1:100, 2:100 and 5: 100 (g of dried Moringa oleifera seeds: ml of distilled water) were used to extract the protein by using a domestic blender for 2 minutes. Using the Bradford method, the absorbance for each solid to solvent ratio solution was recorded and the protein content concentration was further calculated. The highest protein content concentration of 0.0017 ug/uL was obtained in the best solid to solvent ratio which is 5.0: 100. Therefore, this solid to solvent ratio was used in the jar test. The jar test was based on three process parameters which includes coagulant dosage, pH and initial concentration of dye wastewater. The coagulant dosage of 300 mg/L, initial concentration of dye wastewater of 50 ppm and pH of 7 were selected as the most optimum process parameters for a maximum turbidity removal of 70.4% and a maximum color removal of 44.54% in the dye wastewater treatment with Moringa Oleifera seeds.</jats:p

Kinetic characterization of a low-dissolved‑oxygen oxic-anoxic process treating low COD/N tropical wastewater revealed selection of nitrifiers with high substrate affinity

The design of wastewater treatment plants in the tropics is largely based on default parameters from the studies in temperate climates. This may lead to suboptimal design, such as the intensive aeration required for biological nitrogen removal. To reduce the aeration energy, a low-dissolved-oxygen oxic-anoxic (low-DO OA) process was developed for treating low chemical oxygen demand-to-nitrogen (COD/N) tropical wastewater. This study calibrated the growth kinetic parameters of microbes in a conventional anoxic-oxic (AO) and a low-DO OA sequencing batch reactors (SBRs) based on a modified version of Activated Sludge Model No. 1 (ASM1). We selected three parameters to be calibrated, namely the maximum growth rate of heterotrophs (mu(H)), maximum growth rate of nitrifiers (mu(A)) and nitrifiers' affinity towards ammoniacal nitrogen (NH4+ -N) (KNH). The low-DO OA SBR selected for microbes with a low mu(H) (2.2 d(-1)), mu A (1.49 d-1) and KNH (0.035 mg NH4+ -N L-1), which supported the observed proliferation of K-strategist Nitrospira at low-DO condition (0.4 +/- 0.2 mg O-2 L-1). The calibrated parameters for the AO SBR (1.7 +/- 0.2 mg O-2 L-1) were significantly higher (mu H=9.3 d(-1), mu A=4.49 d(-1), KNH=6.3 mg NH4+ -N L-1) than the low-DO OA SBR. The calibrated ASM1 adequately simulated the low-DO OA SBR performance under different sludge retention times. The findings demonstrated a kinetic insight into the unique K-strategist nitrifiers in a low-DO OA process. Moreover, this study reinforced the importance of using parameters for tropical wastewater rather than relying on default values from studies in temperate climates