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The study aims to explore the effects of Eugenol (EUG) as an antioxidant on α-Chymotrypsin (α-Chy) and its interaction mechanism, with potential implications for new therapy development. The interaction between EUG and α-Chy was demonstrated through ultraviolet (UV) spectroscopy, which resulted in a shift in absorption with docking energies of -22.76 kJ/mol. An increase in fluorescence intensity indicated that the Trp residues moved to a less polar environment, which is consistent with the changes in accessible surface area (ASA) values. The presence of EUG led to a decrease in α-helix, β-turn, and random coil structures as shown by circular dichroism (CD) and Fourier-transform infrared (FTIR) analysis. Additionally, there was a slight increase in β-sheet structures, indicating a decrease in enzyme stability. However, tests for thermal stability showed a decrease in folding upon the introduction of EUG, which contradicted the results obtained from molecular dynamics (MD) simulations. The docking studies revealed that EUG forms hydrogen bonds and van der Waals forces with the enzyme, indicating the interaction mechanism. Kinetic studies confirmed that EUG acts as a mixed inhibitor. However, further research involving live organisms is necessary to fully understand its potential., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Dry powder inhalers (DPIs) are the first choice for inhalation drug development. However, some conventional DPI formulation processes require heating, which may damage high molecular weight drugs such as proteins and nucleic acids. In this study, we propose a novel DPI preparation process that avoids the use of heat. Dry powders were prepared by cryomilling nanofiber mats composed of polyvinyl alcohol, D(-)-mannitol (Man), and α-chymotrypsin (α-Chy) as the model drug using the electrospinning method. The addition of Man conferred high dispersibility and excellent in vitro aerosol performance to the nanofiber mat powder in a very short milling time (less than 0.5 min) as assessed using the Andersen cascade impactor. Powders were classified according to the degree of friability, and among these, nanofiber mats containing 15 % Man and milled for 0.25 min exhibited the highest aerosol performance. Nanofiber mats containing Man milled for less than 0.5 min also exhibited greater α-Chy enzymatic activity than a nebulized α-Chy solution. Furthermore, single inhalation induced no significant lung tissue damage as evidenced by lactate dehydrogenase activity assays of mouse bronchoalveolar lavage fluid. This novel DPI formulation process may facilitate the safe and efficient inhalational delivery of therapeutic proteins., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Abamectin has been extensively used in paddy fields to control insect pests. However, little information is available regarding its effects on non-target insects. In this study, we performed acute (3rd instar larvae) and chronic toxicity (newly hatched larvae <24 h) to determine the toxicity effects of abamectin on Chironomus kiiensis. The median lethal concentration (LC 50 ) values of 24 h and 10 d were 0.57 mg/L and 68.12 μg/L, respectively. The chronic exposure significantly prolonged the larvae growth duration and inhibited pupation and emergence. The transcriptome and biochemical parameters were measured using 3rd instar larvae exposed to acute LC 10 and LC 25 for 24 h. Transcriptome data indicated that five trypsin and four chymotrypsin genes were downregulated, and RT-qPCR verified a significant expression decrease in trypsin3 and chymotrypsin1 genes. Meanwhile, abamectin could significantly inhibit the activities of the serine proteases trypsin and chymotrypsin. RNA interference showed that silencing trypsin3 and chymotrypsin1 genes led to higher mortality of C. kiiensis to abamectin. In conclusion, these findings indicated that trypsin and chymotrypsin are involved in the abamectin toxicity against C. kiiensis, which provides new insights into the mechanism of abamectin-induced ecotoxicity to chironomids., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

This study investigates the controlled release of α-chymotrypsin from an alginate hydrogel matrix. When protein molecules entrapped in the hydrogel matrix have a size smaller than the hydrogel pores, their hold/release from the polymer matrix are controlled by the electrostatic interaction between the guest molecules and host polymer. α-Chymotrypsin, as a model protein, was chemically modified with negatively charged species to change its pI and to convert its attractive interaction with a negatively charged alginate hydrogel matrix to a repulsion interaction allowing its release by pH-triggered signal. Then, bulk pH changes and electrochemically controlled local pH changes resulting from oxygen reduction were used for the controlled release of the enzyme from the alginate hydrogel. Three batches of modified α-chymotrypsin with different linker/enzyme ratios were synthesized, and their release profiles were investigated. The activity of both unmodified and modified α-chymotrypsin was evaluated using a UV-visible spectrophotometer following the standard procedure for the enzymatic assay of α-chymotrypsin (EC 3.4.21.1) and compared across all batches. Direct infusion electrospray ionization mass spectrometry (DI ESI-MS) was used to analyze the protein modifications and their impact on the isoelectric point values., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In the present study, the interaction mechanism between gallic acid (GA) and α-Chymotrypsin (α-CT) was investigated by employing a series ofspectroscopic methods, computational docking and molecular dynamic (MD) simulation. Fluorescence spectra analysis indicated the formation of a stable complex between GA and α-CT, where the quenching of the fluorescence emission was predominantly characterized by a static mechanism. TheCA obtained binding constants for the α-CT-GA complex were in the order of 10 3 M -1 , indicating the moderate binding affinity of GA for α-CT. The corresponding CD findings showed that the interaction between GA and α-CT resulted in an alteration of the protein's secondary structure. The findings of the enzyme activity investigation clearly showed that the presence of GA led to a notable decline in the enzymatic activity of α-CT, highlighting GA's function as an effective inhibitor for α-CT. The molecular docking simulations revealed the optimal binding site for the GA molecule within the α-CT structure and MD simulations confirmed the stability of the α-CT-GA complex. This research expands our comprehension regarding the behavior of enzymes in the presence of small-molecule ligands and opens avenues for food safety., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Among various herbal plants, saffron has been the subject of study in various medical and food fields. Among the compounds of saffron, safranal is one of them. Safranal is a monoterpene aldehyde. The precursor of safranal is called picrocrocin, whose hydrolysis leads to the production of safranal. picrocrocin has two sugar components and aglycone. sugar component was separated during the drying process of saffron and safranal is produced. Saffron is the cause of the saffron aroma. Previous studies have shown that safranal offers many benefits such as antioxidants, blood pressure regulation and anti-tumor qualities. On the other hand, α-Chy is an enzyme secreted by the pancreas into the intestine and then acts as an efficient protease. In this study, various methods, such as molecular dynamics (MD) simulation and molecular binding, and different spectroscopic techniques, as well as protein stability techniques, were used to investigate the possible interactions between safranal and α-Chy. UV spectroscopic studies were showing that the existence of safranal decreased α-Chy absorption intensity. safranal caused the intrinsic fluorescence of α-Chy to be quenched too. According to the Stern-Volmer equation, the interaction between safranal and α-Chy was of the static type. In thermodynamic calculations, the interaction between safranal and α-Chy was stabilized by hydrophobic forces. And it was found that this interaction continued spontaneously. These results were, thus, consistent with the Docking data simulation (with the negative ΔG° number and positive changes in enthalpy and entropy). The thermal stability of α-Chy was also measured, showing that its melting point was shifted to a higher threshold as a result of the interaction. also, MD simulation indicated that α-Chy became more stable in the presence of safranal. In this paper, all the results of the laboratory techniques were confirmed by molecular dynamic simulations, so the correctness of the results was confirmed. From this research, we hope to carefully observe the possible changes in the behavior and structure of the enzyme in the presence of safranal.Communicated by Ramaswamy H. Sarma.

Secondary metabolites produced by primary producers have a wide range of functions as well as indirect effects outside the scope of their direct target. Research suggests that protease inhibitors produced by cyanobacteria influence grazing by herbivores and may also protect against parasites of cyanobacteria. In this study, we asked whether those same protease inhibitors produced by cyanobacteria could also influence the interactions of herbivores with their parasites. We used the Daphnia‐Metschnikowia zooplankton host‐fungal parasite system to address this question because it is well documented that cyanobacteria protease inhibitors suppress trypsin and chymotrypsin in the gut of Daphnia, and because it is known that Metschnikowia infects via the gut. We tested the hypothesis that Daphnia gut proteases are necessary for Metschnikowia spores to be released from their asci. We then also tested whether diets that decrease trypsin and chymotrypsin activity in the guts of Daphnia lead to lower levels of infection. Our results show that chymotrypsin promotes the release of the fungal spores from their asci. Moreover, a diet that strongly inhibited chymotrypsin activity in Daphnia decreased infection levels, particularly in the most susceptible Daphnia clones. Our results support the growing literature that cyanobacterial diets can be beneficial to zooplankton hosts when challenged by parasites and uncover a mechanism that contributes to the protective effect of cyanobacterial diets. Specifically, we demonstrate that host chymotrypsin enzymes promote the dehiscence of Metschnikowia spores; when cyanobacteria inhibit the activity of chymotrypsin in hosts, this most likely traps the spore inside the ascus, preventing the parasite from puncturing the gut and beginning the infection process. This study illustrates how secondary metabolites of phytoplankton can protect herbivores against their own enemies. [ABSTRACT FROM AUTHOR]

Background: Lung cancer diagnosis, staging and treatment may be enhanced by multidisciplinary participation and presentation in multidisciplinary meetings (MDM). We performed a systematic review and meta-analysis to explore literature evidence of clinical impacts of MDM exposure. Methods: A study protocol was registered (PROSPERO identifier CRD42021258069). Randomised controlled trials and observational cohort studies including adults with nonsmall cell lung cancer and who underwent MDM review, compared to no MDM, were included. MEDLINE, CENTRAL, Embase and ClinicalTrials.gov were searched on 31 May 2021. Studies were screened and extracted by two reviewers. Outcomes included time to diagnosis and treatment, histological confirmation, receipt of treatments, clinical trial participation, survival and quality of life. Risk of bias was assessed using the ROBINS-I (Risk of Bias in Non-randomised Studies – of Interventions) tool. Results: 2947 citations were identified, and 20 studies were included. MDM presentation significantly increased histological confirmation of diagnosis (OR 3.01, 95% CI 2.30–3.95; p<0.00001) and availability of clinical staging (OR 2.55, 95% CI 1.43–4.56; p=0.002). MDM presentation significantly increased likelihood of receipt of surgery (OR 2.01, 95% CI 1.29–3.12; p=0.002) and reduced the likelihood of receiving no active treatment (OR 0.32, 95% CI 0.21–0.50; p=0.01). MDM presentation was protective of both 1-year survival (OR 3.23, 95% CI 2.85–3.68; p<0.00001) and overall survival (hazard ratio 0.63, 95% CI 0.55–0.72; p<0.00001). Discussion: MDM presentation was associated with increased likelihood of histological confirmation of diagnosis, documentation of clinical staging and receipt of surgery. Overall and 1-year survival was better in those presented to an MDM, although there was some clinical heterogeneity in participants and interventions delivered. Further research is required to determine the optimal method of MDM presentation, and address barriers to presentation. [ABSTRACT FROM AUTHOR]