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Depleting fossil fuels and net carbon emissions associated with their burning have driven the need to find alternative energy sources. Biofuels are near-perfect candidates for alternative energy sources as they are renewable and account for no net CO2 emissions. However, biofuel production must overcome various challenges to compete with conventional fuels. Conventional methods for bioconversion of biomass to biofuel include chemical, thermochemical, and biological processes. Substrate selection and processing, low yield, and total cost of production are some of the main issues associated with biofuel generation. Recently, the uses of nanotechnology and nanoparticles have been explored to improve the biofuel production processes because of their high adsorption, high reactivity, and catalytic properties. The role of these nanoscale particles and nanocatalysts in biomass conversion and their effect on biofuel production processes and yield are discussed in the present article. The applicability of nanotechnology in production processes of biobutanol, bioethanol, biodiesel, biohydrogen, and biogas under biorefinery approach are presented. Different types of nanoparticles, and their function in the bioprocess, such as electron transfer, pretreatment, hydrolysis, microalgae cultivation, lipid extraction, dark and photo fermentation, immobilization, and suppression of inhibitory compounds, are also highlighted. Finally, the current and potential applications of nanotechnology in biorefineries are also discussed.
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Bioethanol is an appropriate alternate energy option due to its renewable, nontoxic, environmentally friendly, and carbon-neutral nature. Depending upon various feedstocks, bioethanol is classified in different various generations. First-generation ethanol created a food vs fuel problem, which was overcome by second-generation, third-generation and fourth-generation ethanol. The considerable availability of lignocellulosic biomass makes it a suitable feedstock, however, its recalcitrant nature is the main hurdle in converting it to bioethanol. The present study gives a comprehensive assessment of global biofuel policies and the current status of ethanol production. Feedstocks for first-generation (sugar and starch-based), second-generation (lignocellulosic biomass and energy crops), third-generation (algal-based) and fourth-generation (genetically modified algal biomass or crops) are discussed in detail. The study also assessed the process for ethanol production from various feedstocks, besides giving a holestic background knowledge on the bioconversion process, factors affecting bioethanol production, and various microorganisms involved in the fermentation process. Biotechnological tools also play a pivotal role in enhancing process efficiency and product yield. In adddition, most significant development in the field of genetic engineering and adaptive evolution are also highlighted.
Global biofuels policies on bioethanol production were presentedTechnological integrations of 1G, 2G, 3G and 4G bioethanol were discussedVarious factors affecting bioethanol production were mentionedTechno-economic analysis and LCA of bioethanol production are discussed.
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Biotecnología , Ingeniería Genética , Almidón , Etanol , Biocombustibles , Biomasa , Fermentación , Productos Agrícolas/metabolismoRESUMEN
The paper highlights the synergistic potential of the novel combination of Camellia sinensis (Kangra green tea) and Withania somnifera (Ashwagandha). One variable at a time approach was used to find antioxidant potential of C. sinensis and W. somnifera alone and in combination. Optimization of antioxidant potential was done by using different plant concentrations of C. sinensis and W. somnifera using a statistical approach of central composite design (CCD) of RSM (response surface methodology). Initial antioxidant activity during optimization of the solvent system was observed in methanol for C. sinensis with DPPH, superoxide radical scavenging assay and hydrogen peroxide scavenging assay (44.9 ± 0.62, 43.77 ± 0.10, 43.88 ± 0.10% scavenging) and for W. somnifera (40.22 ± 0.39, 43.29 ± 1.12, 41.88 ± 0.11% scavenging), respectively. Initially, IC50 has been calculated for C. sinensis (235.26 ± 0.012 µg/mL) and W. somnifera (256.39 ± 0.43 µg/mL) in methanol. Before statistical optimization, the maximum synergistic antioxidant potential of C. sinensis (200 µg/mL) and W. somnifera (150 µg/mL) with DPPH assay, superoxide radical scavenging and hydrogen peroxide scavenging assay was found to be 56.57 ± 0.62, 56.99 ± 0.42, 55.44 ± 0.53% scavenging, respectively. IC50 value has been calculated for C. sinensis + W. somnifera (IC50 = 215.47 ± 0.06 µg/mL). Optimization of plant concentration using CCD of RSM resulted in enhancement of antioxidant potential of C. sinensis (200.5 µg/mL) and W. somnifera (200.5 µg/mL) was found to be 78.01 ± 0.01% scavenging when compared to the initial antioxidant potential, i.e., 56.57 ± 0.62% scavenging shows a 1.37-fold increase from initial antioxidant potential. Research unveils that using various combination of C. sinensis and W. somnifera enhance the antioxidant potential in vitro. Supplementary Information: The online version contains supplementary material available at 10.1007/s40011-022-01423-6.
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[This retracts the article DOI: 10.7759/cureus.19487.].
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[This retracts the article DOI: 10.7759/cureus.18803.].
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Lignocellulosic biomass generated from different sectors (agriculture, forestry, industrial) act as biorefinery precursor for production of second-generation (2G) bioethanol and other biochemicals. The integration of various conversion techniques on a single platform under biorefinery approach for production of biofuel and industrially important chemicals from LCB is gaining interest worldwide. The waste generated on utilization of bio-resources is almost negligible or zero in a biorefinery along with reduced greenhouse gas emissions, which supports the circular bioeconomy concept. The economic viability of a lignocellulosic biorefinery depends upon the efficient utilization of three major components of LCB-cellulose, hemicellulose and lignin. The heterogeneous structure and recalcitrant nature of LCB is main obstacle in its valorization into bioethanol and other value-added products. The success of bioconversion process depends upon methods used during pre-treatment, hydrolysis and fermentation processes. The cost involved in each step of the bioconversion process affects the viability of cellulosic ethanol. The lignocellulose biorefinery has ample scope, but much-focused research is required to fully utilize major parts of lignocellulosic biomass with zero wastage. The present review entails lignocellulosic biomass valorization for ethanol production, along with different steps involved in its production. Various value-added products produced from LCB components were also discussed. Recent technological advances and significant challenges in bioethanol production are also highlighted in addition to future perspectives.
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INTRODUCTION: This study was conducted to determine whether remdesivir administration for treatment of coronavirus disease 2019 (COVID-19) is associated with reducing deaths among COVID-19 hospitalized patients. METHODOLOGY: It was a retrospective study, and the data was acquired at Ziauddin Hospital in Karachi, Pakistan. All patients admitted between February and May 2021 with severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) infection confirmed by polymerase chain reaction testing from nasopharyngeal samples were included in the study, including those who received at least five-day treatment of remdesivir and who did not receive even a single dose of remdesivir. RESULTS: Data of overall 174 patients were used, out of which 71 (40.80%) received remdesivir. After propensity score matching, 71 patients in the remdesivir group were successfully matched with the non-remdesivir patients on the basis of age, gender, and disease severity. Results of multivariable logistic regression showed that there is no significant difference in deaths between patients who received remdesivir and patients who did not receive remdesivir (p-value=0.122). However, the length of hospital stay was significantly lower in the remdesivir group than in the control group (p-value=0.001). CONCLUSION: Results of this study can provide evidence that remdesivir can be efficient in reducing the duration of COVID-19 illness, and a five-day course of treatment is sufficient for patients to get clinical benefits.
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Introduction Multimorbidity is defined as the coexistence of more than one chronic condition in one individual. It is related to enhanced rates of disability and mortality, enhanced disease burden, decreased function levels, and it can affect the wellbeing and daily activities of people, including loss of autonomy and independence. The aim of the current study is to determine the predictors of quality of life among patients with multimorbidity in Karachi, Pakistan. Methodology It was a cross-sectional study conducted in 12 health care facilities of six districts in Karachi, Pakistan. Two health care facilities were selected from each district using a convenient sampling technique. The total sample size of this study was 690, equally distributed among 12 health care facilities. Results The majority of participants (33.47%) belonged to the age group of 40 to 49 years, while 29.85% of participants had an age between 30 to 39 years. More than half of the participants were females (50.87%). Overall, the multivariate analysis showed being male, married, younger, high educational status and employed were positively associated with quality of life. While having lower family income is negatively associated with quality of life. Conclusion The findings of this study had important implications for identifying distinct multimorbidity individuals who were at risk of a lower quality of life, and they emphasized the need for disease detection and treatment at an early stage. The study can also give important evidence for decision-makers when it comes to allocating health resources more efficiently, and health administrative departments can improve chronic disease management.
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OBJECTIVES: To explore the aetiological, clinical and radiological profiles of patients with LETM presenting to this tertiary care hospital in North India. PATIENTS AND METHODS: All eligible LETM patients presenting to our hospital between April 2015 and Jan 2016 were prospectively studied. A total of 37 patients were included and after thorough history, examination, relevant laboratory and radiological investigation, were profiled according to the various aetiologies of LETM. RESULTS: Our study included 37 patients (62% males and 38% females). Most patients were young (21-30 years). Main aetiologies of LETMp were NMO (8), inflammatory (9), idiopathic (6), NMOSD (4), Vitamin B12 deficiency (4) and others (6). Most patients (62%) had acute onset of symptoms except NMOSD and B12 deficient patients who presented subacutely too. NMO group was most disabled (poor Rankin and MRC assessments) at presentation; prognostically no (87%) or minimal improvement (13%) at discharge was seen in this group compared to other aetiologies. Forty point five percent patients had thoracic sensory complaints. CSF (pleocytosis 62%) and raised protein (81%) and brain abnormalities on MRI were seen in 11% patients. Bladder and optic nerve involvement (75.7% and 35% patients respectively). Seventy five percent NMO and 67% probable inflammatory aetiology patients also had B12 deficiency. CONCLUSION: This study concludes that LETMp has varied aetiologies with NMO having more disability and poorer outcomes. Thoracic cord segment is most commonly involved. Vitamin B12 deficiency may predispose patients to inflammatory LETM including NMO syndromes.