Biofilm Engineering Approaches for Improving the Performance of Microbial Fuel Cells and Bioelectrochemical Systems

Microbial fuel cells (MFCs) are emerging as a promising future technology for a wide range of applications in addition to sustainable electricity generation. Electroactive (EA) biofilms produced by microorganisms are the key players in the bioelectrochemical systems involving microorganism mediated electrocatalytic reactions. Therefore, genetically modifying the organism for increased production of EA biofilms and improving the extra electron transfer (EET) mechanisms may attribute to increase in current density of a MFC and an increased COD removal in wastewater treatment plant coupled MFC systems. Extracellular polysaccharides (EPS) produced by the organisms attribute to both biofilm formation and electron transfer. Although cell surface modification, media optimization and operation parameters validation are established as enhancement strategies for a fuel cell performance, engineering the vital genes involved in electroactive biofilm formation is the future hope. Therefore, in this review we critically address the biofilm formation mechanisms in electro active microorganisms, strategies for improving the biofilm formation leading to improved electrocatalytic rates for applications in bioelectrochemical systems

Phlorotannins from Brown Algae: inhibition of advanced glycation end products formation in high glucose induced <i style="mso-bidi-font-style:normal">Caenorhabditis elegans</i>

371-379Advanced Glycation End products (AGE) generated in a non enzymatic protein glycation process are frequently associated with diabetes, aging and other chronic diseases. Here, we explored the protective effect of phlorotannins from brown algae Padina pavonica, Sargassum polycystum and Turbinaria ornata against AGEs formation. Phlorotannins were extracted from brown algae with methanol and its purity was analyzed by TLC and RP-HPLC-DAD. Twenty five grams of P. pavonica, S. polycystum, T. ornata yielded 27.6±0.8 µg/ml, 37.7 µg/ml and 37.1±0.74 µg/ml of phloroglucinol equivalent of phlorotannins, respectively. Antioxidant potentials were examined through DPPH assay and their IC50 values were P. pavonica (30.12±0.99 µg), S. polycystum (40.9±1.2 µg) and T. ornata (22.9±1.3 µg), which was comparatively lesser than the control ascorbic acid (46±0.2 µg). Further, anti-AGE activity was examined in vitro by BSA-glucose assay with the extracted phlorotannins of brown algae (P. pavonica, 15.16±0.26 µg/ml; S. polycystum, 35.245±2.3 µg/ml; T. ornata,<i style="mso-bidi-font-style: normal"> 22.7±0.3 µg/ml), which revealed the required concentration to inhibit 50% of albumin glycation (IC50) were lower for extracts than controls (phloroglucinol, 222.33±4.9 µg/ml; thiamine, 263 µg/ml). Furthermore, brown algal extracts containing phlorotannins (100 µl) exhibited protective effects against AGE formation <i style="mso-bidi-font-style: normal">in vivo in C. elegans with induced hyperglycemia.<span style="mso-bidi-font-family: GCFrutiger-Bold" lang="EN-GB"> </span

Prediction of COVID-19 with Computed Tomography Images using Hybrid Learning Techniques

Reverse Transcription Polymerase Chain Reaction (RT-PCR) used for diagnosing COVID-19 has been found to give low detection rate during early stages of infection. Radiological analysis of CT images has given higher prediction rate when compared to RT-PCR technique. In this paper, hybrid learning models are used to classify COVID-19 CT images, Community-Acquired Pneumonia (CAP) CT images, and normal CT images with high specificity and sensitivity. The proposed system in this paper has been compared with various machine learning classifiers and other deep learning classifiers for better data analysis. The outcome of this study is also compared with other studies which were carried out recently on COVID-19 classification for further analysis. The proposed model has been found to outperform with an accuracy of 96.69%, sensitivity of 96%, and specificity of 98%

Production of biodiesel from cyanobacteria (<i>Oscillatoria annae) </i>by alkali and enzyme mediated transesterification

959-967This study presents lipids from Oscillatoria annae BDU6, a freshwater cyanobacterium, to generate biodiesel. Efficient oil extraction from O. annae was achieved by ultrasonication in combination with organic solvents (50.9%) than homogenization (40.4%). Efficient conversion of triglycerides of O. annae into biodiesel was obtained by alkali mediated transesterification (86% w/v) when compared with lipase-mediated transesterification (76.5% w/v). RSM and CCRD were employed to optimize the growth medium to improve biomass of O. annae, which resulted in 3.2-fold increase in biomass yield (5.3 g-l dry wt/g of inoculum) compared to initial level (1.6 g-l dry wt/g of inoculum)

Riboflavin Responsive Mitochondrial Dysfunction in Neurodegenerative Diseases

Mitochondria are the repository for various metabolites involved in diverse energy-generating processes, like the TCA cycle, oxidative phosphorylation, and metabolism of amino acids, fatty acids, and nucleotides, which rely significantly on flavoenzymes, such as oxidases, reductases, and dehydrogenases. Flavoenzymes are functionally dependent on biologically active flavin adenine dinucleotide (FAD) or flavin mononucleotide (FMN), which are derived from the dietary component riboflavin, a water soluble vitamin. Riboflavin regulates the structure and function of flavoenzymes through its cofactors FMN and FAD and, thus, protects the cells from oxidative stress and apoptosis. Hence, it is not surprising that any disturbance in riboflavin metabolism and absorption of this vitamin may have consequences on cellular FAD and FMN levels, resulting in mitochondrial dysfunction by reduced energy levels, leading to riboflavin associated disorders, like cataracts, neurodegenerative and cardiovascular diseases, etc. Furthermore, mutations in either nuclear or mitochondrial DNA encoding for flavoenzymes and flavin transporters significantly contribute to the development of various neurological disorders. Moreover, recent studies have evidenced that riboflavin supplementation remarkably improved the clinical symptoms, as well as the biochemical abnormalities, in patients with neuronopathies, like Brown-Vialetto-Van-Laere syndrome (BVVLS) and Fazio-Londe disease. This review presents an updated outlook on the cellular and molecular mechanisms of neurodegenerative disorders in which riboflavin deficiency leads to dysfunction in mitochondrial energy metabolism, and also highlights the significance of riboflavin supplementation in aforementioned disease conditions. Thus, the outcome of this critical assessment may exemplify a new avenue to enhance the understanding of possible mechanisms in the progression of neurodegenerative diseases and may provide new rational approaches of disease surveillance and treatment

Agro Waste Utilization for Cost-Effective Production of l‑Asparaginase by Pseudomonas plecoglossicida RS1 with Anticancer and Acrylamide Mitigation Potential

Agricultural wastes such as the peels of onion and garlic were used as a supplement along with l-asparagine for the very first time to produce increased yield of l-asparaginase by Pseudomonas plecoglossicida RS1. Statistical optimization strategies such as response surface methodology were used to generate a medium composition containing extracts of 0.9 (v/v) of garlic peel waste and 0.5% (v/v) onion peel waste along with 0.2% (w/w) l-asparagine, which yielded a twofold increase in the enzyme activity compared to the unsupplemented minimal (M-9) medium. The presence of l-asparagine content in the peel extract was confirmed by high-performance liquid chromatography. Further, l-asparaginase was purified to homogeneity, and identity was confirmed by matrix-assisted laser desorption ionization time-of-flight analysis. The application of the purified l-asparaginase as a therapeutic was studied in HeLa cells which showed a p53-mediated G₂ cell cycle arrest. Moreover, the purified l-asparaginase showed effective acrylamide mitigation in vitro, at 6 IU, and its effective degradation was also demonstrated by the effect on chemotactic index of Caenorhabditis elegans and the restoration of the cognitive abilities of C. elegans which was coexposed to acrylamide and l-asparaginase compared to that exposed to acrylamide alone. Thus, l-asparaginase, with multipotent applications, was produced by effective waste utilization for economical commercial production

Study of anti-inflammatory, anti-diabetic, and analgesic activity of Oscillatoria annae extract in rats and mice

The aqueous extract of the cyanobacterium Oscillatoria annae was investigated for its anti-inflammatory, anti-diabetic,analgesic and cholesterol regulating properties in different experimental standard animal models. The non-steroidal anti-inflammatory drug, indomethacin (10 mg/kg/body weight) was used as standard in the anti-inflammatory, and analgesic studies, while glibenclamide (600 μg/kg/b.wt.) was used as standard drug in the anti-diabetic study. The results reveal that O. annae possesses significant ameliorating effects in the studied animal models, including rats and mice. These effects were comparable to those obtained after treatment with the standard drugs used in this study. The results indicate that the cyanobacterial extract can act as natural remedy and also open a new avenue to identify the active ingredients behind these effects.Keywords: Oscillatoria annae, anti-inflammatory, anti-diabetic, analgesic, cholestero