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In this study, imines bearing quinazolin‐4(3H)‐one were synthesized and their inhibitory properties were investigated against some metabolic enzymes including Acetylcholinesterase (AChE), Butyrylcholinesterase (BChE), α‐Glycosidase (α‐Gly), and human Carbonic Anhydrase I–II (hCA I–II). All compounds had inhibitory strength with Ki values in the range of 38.55±4.08–159.05±10.68 nM and 41.04±6.73–177.12±8.06 nM against hCA I and hCA‐II, respectively in comparison to the standard acetazolamide (AZA) Ki=125.15±0.78 nM (for hCA‐I) and Ki=148.75±0.92 nM (for hCA‐II). The compounds showed potent inhibitory activity against α‐Gly enzyme with IC50 value 0.34–2.28 nM (standard inhibitor acarbose (ACR): 3.18 nM). Also, these analogs had potent inhibitory strength with Ki values in the range of 4.20±0.15–26.10±2.36 nM against AChE and 1.22±0.05–16.09±0.88 nM against BChE in comparison to the standard tacrine (TAC) Ki=37.62±6.86 nM (for AChE) and Ki=26.75±5.79 nM (for BChE). Additionally, the molecular docking and molecular dynamics simulation study was carried out for the determination of ligand‐enzyme interactions. The docking scores of the most active compound were calculated as −7.31, −7.59, −6.66, −6.93 and −7.11 kcal/mol for AChE, BChE, hCA I, hCA II, and α‐Gly, respectively. [ABSTRACT FROM AUTHOR]

Because of high porosity and stickiness of mint leaves, they could not be fluidized well during fluidization. In this study, a vibro-fluidized bed dryer assisted heat pump system was designed and fabricated to overcome this problem. The drying experiments were carried out at temperatures of 40, 50 and 60 °C. The quality of the dehydrated samples was assessed based on color indices, antioxidant activity, and total phenolic content. Drying process primarily occurred in falling rate period. The effective coefficient of moisture transfer of the samples was increased with air temperature and varied from 4.26656×10-11 to 2.95872×10-10 m2 s-1 for heat pump drying (HPD) method, and 3.71918×10-11 to 1.29196×10-10 m2 s-1 for none-heat pump drying (NHPD) method. The color indices for temperatures of 40 and 50 °C were very close to each other, whereas by increasing temperature to 60 °C, a remarkable loss of green color was observed. The highest phenolic content was found in methanolic extract for HPD at 60 °C, and NHPD at 50 °C contained the lowest amount of phenolic compounds. NHPD treatments showed lower antioxidant activity compared to HPD treatments at the same temperature due to the longer drying times.

In this work, the inhibitory ability and mechanism of ω3‐nicotinic acid (ω3‐NA) and ω3‐Picolinic acid (ω3‐PA) complexes on the activity of mushroom tyrosinase (MT) were scrutinized for progressing a novel MT inhibitor. The complexes were synthesized. It was shown to have a considerable inhibition on the MT activity and Ki value of ω3‐NA and ω3‐PA on MT equal to 5.2 and 5.1 mM, respectively. ω3‐NA and ω3‐PA inhibited MT with Vmax values in the range of 0.134 mM and 0.14 mM, respectively. The outputs obtained from fluorescence quenching specified that ω3‐NA and ω3‐PA could interact with MT. Especially, the decrease in fluorescence intensity was due to the formation of a ligand‐enzyme complex which was mostly motivated by hydrogen bonding and hydrophobic forces. The presence of ω3‐NA and ω3‐PA altered the structure of MT and reduced the α‐helix of the enzyme. Molecular docking investigation along with molecular dynamics simulation exhibited that ligands‐MT formation is directed by hydrogen binding with Trp136, His263, and Val299 residues. The results highlight that ω3‐NA and ω3‐PA can be considered as possible inhibitors in treating hyperpigmentation via MT enzyme inhibition. [ABSTRACT FROM AUTHOR]

Inhibition of intestinal α‐glucosidase (αGS), a crucial enzyme in carbohydrate digestion, is an effective therapeutic approach for diabetes mellitus treatment. The C‐glycosylflavonoids (CGFs) are natural compounds with antioxidant, antidiabetic, and anti‐inflammatory activities. The present work seeks an alternative compound among CGFs that can control the blood glucose level by inhibiting αGS enzyme activity. Therefore, ten CGFs were selected and carried out the docking to αGS. The docking outcomes proposed that among selected CGFs, the orientin compound can successfully interact with the key residues of Asp215, Glu277, Asp352, Arg442, and Arg446. Of them, the orientin compound with docking energy of −6.11 Kcal/mol, was subsequently subjected to molecular dynamics simulation (MDs), and in vitro investigation. MDs results indicated that orientin formed a stable complex with αGS enzyme. We also performed molecular mechanics generalized Born and surface area (MM/GBSA) free energy calculation manner on all chosen CGFs along with miglitol as reference. The IC50 value of orientin for αGS inhibition with competitive mode was found to be 0.13 mg/ml. The results highlight that orientin can be considered as a possible compound in treating DM via αGS inhibition. However, further in vitro and in vivo analyses are required to confirm this claim. [ABSTRACT FROM AUTHOR]

In this study, (E)‐N′(3,5‐di‐tert‐butil‐2‐hedroxybenzilidene)‐2‐hydroxybenzohydrazide (H3sahz)2 and its copper (II) complex has been synthesized and evaluated by methods FTIR, UV–Vis, EPR, and single crystal X‐ray analysis. It has been shown, that H3sahz crystallizes as a dimer through hydrogen bonds. H3sahz with copper nitrate forms [Cu(H2sahz)(NO3)(H2O)] complex, which according to X‐ray diffraction analysis has a distorted square pyramidal structure. The complex was screened for α‐glucosidase (α‐Glu), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) inhibitory abilities. Results displayed that IC50 and Ki values of the novel complex for AChE, BChE, and α‐Glu enzymes were obtained at 0.93–2.14, 1.01–2.03, and 73.86–102.65 μM, respectively. The molecular docking outcomes have shown that the synthetic complex has a lower affinity for α‐glucosidase compared to acarbose. But the inhibition ability of H3sahz for acetylcholinesterase and butyrylcholinesterase enzymes was greater than that of tacrine. These findings indicate that the (H3sahz)2 complex may be considered a possible candidate for the development and discovery of compounds effective in inhibiting the relevant enzymes. [ABSTRACT FROM AUTHOR]