Leveraging shape screening and molecular dynamics simulations to optimize PARP1-Specific chemo/radio-potentiators for antitumor drug design.

PARP1 plays a pivotal role in DNA repair within the base excision pathway, making it a promising therapeutic target for cancers involving BRCA mutations. Current study is focused on the discovery of PARP inhibitors with enhanced selectivity for PARP1. Concurrent inhibition of PARP1 with PARP2 and PARP3 affects cellular functions, potentially causing DNA damage accumulation and disrupting immune responses. In step 1, a virtual library of 593 million compounds has been screened using a shape-based screening approach to narrow down the promising scaffolds. In step 2, hierarchical docking approach embedded in Schrödinger suite was employed to select compounds with good dock score, drug-likeness and MMGBSA score. Analysis supplemented with decomposition energy, molecular dynamics (MD) simulations and hydrogen bond frequency analysis, pinpointed that active site residues; H862, G863, R878, M890, Y896 and F897 are crucial for specific binding of ZINC001258189808 and ZINC000092332196 with PARP1 as compared to PARP2 and PARP3. The binding of ZINC000656130962, ZINC000762230673, ZINC001332491123, and ZINC000579446675 also revealed interaction involving two additional active site residues of PARP1, namely N767 and E988. Weaker or no interaction was observed for these residues with PARP2 and PARP3. This approach advances our understanding of PARP-1 specific inhibitors and their mechanisms of action, facilitating the development of targeted therapeutics.

Investigation of the evolved pyrolytic products and energy potential of Bagasse: experimental, kinetic, thermodynamic and boosted regression trees analysis.

This study explored bagasse's energy potential grown using treated industrial wastewater through various analyses, experimental, kinetic, thermodynamic, and machine learning boosted regression tree methods. Thermogravimetry was employed to determine thermal degradation characteristics, varying the heating rate from 10 to 30 °C/min. The primary pyrolysis products from bagasse are H2, CH4, H2O, CO2, and hydrocarbons. Kinetic parameters were estimated using three model-free methods, yielding activation energies of approximately 245.98 kJ mol-1, 247.58 kJ mol-1, and 244.69 kJ mol-1. Thermodynamic parameters demonstrated the feasibility and reactivity of pyrolysis with ΔH ≈ 240.72 kJ mol-1, ΔG ≈ 162.87 kJ mol-1, and ΔS ≈ 165.35 J mol-1 K-1. The distribution of activation energy was analyzed using the multiple distributed activation energy model. Lastly, boosted regression trees predicted thermal degradation successfully, with an R2 of 0.9943. Therefore, bagasse's potential as an eco-friendly alternative to fossil fuels promotes waste utilization and carbon footprint reduction.

Elucidating the pyrolysis reaction mechanism of Calotropis procera and analysis of pyrolysis products to evaluate its potential for bioenergy and chemicals.

The present study was focused on evaluating the bioenergy potential of waste biomass of desert plant Calotropis procera. The biomass was pyrolyzed at four heating rates including 10 °Cmin-1, 20 °Cmin-1, 40 °Cmin-1, and 80 °Cmin-1. The pyrolysis reaction kinetics and thermodynamics parameters were assessed using isoconversional models namely Kissenger-Akahira-Sunose, Flynn-Wall-Ozawa, and Starink. Major pyrolysis reaction occurred between 200 and 450 °C at the conversion points (α) ranging from 0.2 to 0.6 while their corresponding reaction parameters including activation energy, enthalpy change, Gibb's free energy and pre-exponential factors were ranged from 165 to 207 kJ mol-1, 169-200 kJ mol-1, 90-42 kJ mol-1, and 1018-1026 s-1, respectively. The narrow range of pre-exponential factors indicated a uniform pyrolysis, while lower differences between enthalpy change and activation energies indicated that reactions were thermodynamically favorable. The evolved gases were dominated by propanoic acid, 3-hydroxy-, hydrazide, hydrazinecarboxamide and carbohydrazide followed by amines/amides, alcohols, acids, aldehydes/ketones, and esters.

Enhanced oxidative removal of NO by UV/in situ Fenton: Factors, kinetics and simulation.

A series of experiments on the oxidative removal of NO from flue gas using a novel in situ Fenton (IF) system was performed in the presence of ultraviolet light (UV). The comparison tests revealed that the in situ Fenton system facilitated by UV (UV/IF) has a better oxidation ability of NO than that of the IF system due to the photochemical effect on the generation of oxidative species like (OH). Both of the aforementioned oxidation efficiencies were higher than that of the conventional Fenton system (CF) depending on the premix of Fe2+ and H2O2 solutions, which attribute to the improvement of (OH) yield and valid utilization with continuous addition of fresh reagents and UV radiation. In follow-up experiments, the effects of UV power, gas flow rate, reagent temperature, Fe2+/H2O2 molar ratio, initial pH, initial concentration of NO and SO2 and volume fraction O2 and CO2 on the oxidative removal of NO by UV/IF method were investigated respectively. Moreover, the results of kinetic analysis indicated that NO oxidation was confirmed to have a pseudo-first-order kinetics pattern. The rate constants decreased slightly with increasing liquid temperature, and then the apparent activation energy of NO oxidation reactions in the UV/IF system was calculated as -5.62 kJ/mol by the Arrhenius equation. Furthermore, the reaction mechanism and application prospects concerning NO oxidative removal by using the UV/IF system was speculated in brief. Finally, the computational fluid dynamics (CFD) simulations revealed that the improvement of axial and radial gas hold-up would enhance the gas-liquid contact and accelerate the oxidation reactions on the interface. In addition to reasonable control of process parameters, the optimization of reactor interior structure needs to be carried out via CFD simulation and experimental validation in future research, both are favourable to promote the NO oxidation efficiency and large-scale development of this technology.

Bioenergy potential of the residual microalgal biomass produced in city wastewater assessed through pyrolysis, kinetics and thermodynamics study to design algal biorefinery.

The suitability of integrating biological and thermal transformation of microalgal biomass to design a biorefinery was studied. The mixed cultivation of Chlorella sp. and Bracteacoccus sp. in city wastewater produced 12 g L-1 of biomass (0.77 g L-1 day-1) and removed nitrates and phosphates by 68% and 75%, respectively. Microalgae outcompeted the contaminating microbes by raising the pH of wastewater to 9.93. The lipid-free residual biomass was pyrolyzed at four heating rates (10, 20, 30, 40 °C min-1) which showed a three-stage pyrolysis. The activation energies (182-256 kJ mol-1) and their corresponding lower enthalpies at the conversional fractions from 0.2 to 0.6 indicated that product formation was being favored. The values of pre-exponential factors (1015-17 s-1), Gibbs free energy (159-190 kJ mol-1) and entropy (43-81 J mol-1) showed efficient pyrolysis. The data may lead to establish a robust microalgal biorefinery to produce biomass and energy along with primary treatment of city wastewater.

Bioenergy potential of red macroalgae Gelidium floridanum by pyrolysis: Evaluation of kinetic triplet and thermodynamics parameters.

The aim of this study was to investigate the bioenergy potential of red macroalgae GF by evaluating its biofuel physicochemical characteristics, and conducting a kinetic study and thermodynamic analysis of pyrolysis for the first time. The thermal decomposition study was performed at low heating rates (5, 10, 20 and 30 °C min-1) under N2 atmosphere. The thermal behavior of GF pyrolysis indicated the presence of three different decomposition stages, which are associated with different components in its structure and consequently influence the kinetic and thermodynamic parameters. The kinetic triplet obtained for GF provided a suitable description of experimental thermal behavior. The thermodynamic parameters demonstrated that GF is as a new promising feedstock for bioenergy and presented a similar potential to well-known bioenergy feedstock.

Thermodynamics and Kinetics Parameters of Eichhornia crassipes Biomass for Bioenergy.

BACKGROUND: Eichhornia crassipes is an aquatic plant well known for its role in soil reclamation due to the containment of valuable nutrients. Moreover, its biomass is an abundant and low-cost biological resource. Pyrolysis of a biomass offers one of the cleanest methods to harness the bioenergy stored in the biomass. OBJECTIVE: The present study was focused on evaluating the bioenergy potential of Eichhornia crassipes via pyrolysis. METHODS: Biomass of E. crassipes was collected from a municipal wastewater pond. Oven dried powdered biomass of E. crassipes was subjected to pyrolysis at three heating rates including 10, 30 and 50 °C min-1 in a simultaneous Thermogravimetry-Differential Scanning Calorimetry analyzer under an inert environment containing nitrogen. Data obtained were subjected to isoconversional models of Kissenger-Akahira-Sunose (KSA) and Flynn-Wall-Ozawa (FWO) to understand the reaction chemistry. RESULTS: Kinetic parameters have shown that the pyrolysis followed first-order reaction kinetics. The average values of activation energies (129.71-133.03 kJ mol-1) and thermodynamic parameters including high heating values (18.12 MJ kg-1), Gibb's free energies (171-180 kJ mol-1) and enthalpy of reaction (124-127 kJ mol-1) have shown the remarkable bioenergy potential of this biomass. CONCLUSION: This low-cost biomass may be used to produce liquids, gases, and biochar in a costefficient and environmentally friendly way via pyrolysis or co-pyrolysis in the future.

Bioenergy potential of Wolffia arrhiza appraised through pyrolysis, kinetics, thermodynamics parameters and TG-FTIR-MS study of the evolved gases.

This study evaluated the bioenergy potential of Wolffia arrhiza via pyrolysis. The biomass was collected from the pond receiving city wastewater. Oven dried powdered biomass was exposed to thermal degradation at three heating rates (10, 30 and 50°â€¯C min-1) using Thermogravimetry-Differential Scanning Calorimetry analyzer in an inert environment. Data obtained were subjected to the isoconversional models of Kissenger-Akahira-Sunose (KSA) and Flynn-Wall-Ozawa (FWO) to elucidate the reaction chemistry. Kinetic parameters including, Ea (136-172 kJmol-1) and Gibb's free energy (171 kJmol-1) showed the remarkable bioenergy potential of the biomass. The average enthalpies indicated that the product formation is favored during pyrolysis. Advanced coupled TG-FTIR-MS analyses showed the evolved gases to contain the compounds containing CO functional groups (aldehydes, ketones), aromatic and aliphatic hydrocarbons as major pyrolytic products. This low-cost abundant biomass may be used to produce energy and chemicals in a cost-efficient and environmentally friendly way.

Pyrolysis and kinetic analyses of Camel grass (Cymbopogon schoenanthus) for bioenergy.

The aim of this work was to study the thermal degradation of grass (Cymbopogon schoenanthus) under an inert environment at three heating rates, including 10, 30, and 50°Cmin-1 in order to evaluate its bioenergy potential. Pyrolysis experiments were performed in a simultaneous Thermogravimetry-Differential Scanning Calorimetry analyzer. Thermal data were used to analyze kinetic parameters through isoconversional models of Flynn-Wall-Ozawa (FWO) and Kissenger-Akahira-Sunose (KSA) methods. The pre-exponential factors values have shown the reaction to follow first order kinetics. Activation energy values were shown to be 84-193 and 96-192kJmol-1 as calculated by KSA and FWO methods, respectively. Differences between activation energy and enthalpy of reaction values (∼5 to 6kJmol-1) showed product formation is favorable. The Gibb's free energy (173-177kJmol-1) and High Heating Value (15.00MJkg-1) have shown the considerable bioenergy potential of this low-cost biomass.

Pyrolysis, kinetics analysis, thermodynamics parameters and reaction mechanism of Typha latifolia to evaluate its bioenergy potential.

This work was focused on understanding the pyrolysis of Typha latifolia. Kinetics, thermodynamics parameters and pyrolysis reaction mechanism were studied using thermogravimetric data. Based on activation energies and conversion points, two regions of pyrolysis were established. Region-I occurred between the conversion rate 0.1-0.4 with peak temperatures 538K, 555K, 556K at the heating rates of 10Kmin-1, 30Kmin-1, and 50Kmin-1, respectively. Similarly, the Region-II occurred between 0.4 and 0.8 with peak temperatures of 606K, 621K, 623K at same heating rates. The best model was diffusion mechanism in Region-I. In Region-II, the reaction order was shown to be 2nd and 3rd. The values of activation energy calculated using FWO and KAS methods (134-204kJmol-1) remained same in both regions reflecting that the best reaction mechanism was predicted. Kinetics and thermodynamic parameters including E, ΔH, ΔS, ΔG shown that T. latifolia biomass is a remarkable feedstock for bioenergy.

Kinetic analyses and pyrolytic behavior of Para grass (Urochloa mutica) for its bioenergy potential.

The biomass of Urochloa mutica was subjected to thermal degradation analyses to understand its pyrolytic behavior for bioenergy production. Thermal degradation experiments were performed at three different heating rates, 10, 30 and 50°Cmin-1 using simultaneous thermogravimetric-differential scanning calorimetric analyzer, under an inert environment. The kinetic analyses were performed using isoconversional models of Kissenger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO). The high heating value was calculated as 15.04MJmol-1. The activation energy (E) values were shown to be ranging from 103 through 233 kJmol-1. Pre-exponential factors (A) indicated the reaction to follow first order kinetics. Gibbs free energy (ΔG) was measured to be ranging from 169 to 173kJmol-1 and 168 to 172kJmol-1, calculated by KAS and FWO methods, respectively. We have shown that Para grass biomass has considerable bioenergy potential comparable to established bioenergy crops such as switchgrass and miscanthus.