Moringa oleifera flowers: insights into their aroma chemistry, anti-inflammatory, antioxidant, and enzyme inhibitory properties.

BACKGROUND: Moringa oleifera is a highly nutritious plant widely used in traditional medicine. RESULTS: The aroma constituents present in the fresh flowers of M. oleifera versus the hydrodistilled oil and hexane extract were studied using GC-MS. Aldehydes were the major class detected in the fresh flowers (64.75%) with E-2-hexenal being the predominant component constituting > 50%. Alkane hydrocarbons, monoterpenes, and aldehydes constituted > 50% of the hydrodistilled oil, while alkane hydrocarbons exclusively constitute up to 65.48% of the hexane extract with heptacosane being the major component (46.2%). The cytotoxicity of the hexane extract was assessed on RAW 264.7 macrophages using the MTT assay which revealed no significant cytotoxicity at concentrations of 1 µg/mL and displayed IC50 value at 398.53 µg/mL as compared to celecoxib (anti-inflammatory drug) with IC50 value at 274.55 µg/ml. The hexane extract of Moringa flowers displayed good anti-inflammatory activity through suppression of NO, IL-6, and TNF-α in lipopolysaccharide-induced RAW 264.7 macrophages. The total phenolic and flavonoid content in the hexane extract was found to be 12.51 ± 0.28 mg GAE/g extract and 0.16 ± 0.01 mg RuE/g extract, respectively. It displayed moderate antioxidant activity as indicated by the in vitro DPPH, ABTS, CUPRAC, FRAP, and phosphomolybdenum (PBA) assays. No metal chelating properties were observed for the extract. The enzyme inhibitory potential of the hexane extract was evaluated on acetyl- and butyrylcholinesterases (for neuroprotective assessment), α-amylase and α-glucosidase (for antihyperglycemic assessment), and tyrosinase (for dermoprotective assessment) revealing promising results on cholinesterases, tyrosinase, and α-glucosidase. CONCLUSION: Our findings suggested that M. oleifera leaves can be considered as a multidirectional ingredient for preparing functional applications.

In Vivo Glycemic Response of Fruit-Based Mango (Mangifera indica) and Pineapple (Ananas comosus) Bars in In Vitro and In Silico Enzyme Inhibitory Effects Studies.

The habitual consumption of snacks has the potential to enrich or harm the diet. They can contribute to excessive caloric intake and hyperglycemia. Thus, there is an increasing interest in snacks with health-promoting properties. This study aimed to demonstrate the beneficial effect of two fruit-based bars on glucose levels through in vitro, in vivo, and in silico assays. Mango (Mangifera indica L.) and pineapple (Ananas comosus L.) bars (MB and PB) were prepared, and chemical composition, postprandial glycemic response, glycemic index (GI), and glycemic load (GL) were evaluated. The inhibitory effect of fruit bar extracts on α-amylase and α-glucosidase activity and their respective molecular docking was assessed. MB and PB showed the lowest postprandial glycemic response vs. the control bar (p < 0.005), a lower GI (CB: 64.20, PB: 53.20, MB: 40.40), and a GL of 10.9 (CB), 7.9 (PB), and 6.1 (MB), (p < 0.05). MB and PB showed the highest inhibition % of α-amylase (61.44 and 59.37%, respectively) and α-glucosidase (64.97 and 64.57%). Naringenin (-1692.5985 and -2757.674 kcal/mol) and ferulic acid (-1692.8904 and -2760.3513 kcal/mol) exhibited more favorable interaction energies against α-amylase and α-glucosidase activity. The presence of polyphenols from the fruit influenced enzymatic inhibition. Likewise, the dietary fiber in the bars evaluated allowed us to observe a positive effect that favors glycemic control, making them a healthy alternative for snacking.

Inhibition of Enzyme and Bacteria Activities in Diabetic Ulcer-like Scenarios via WAAPV-Loaded Electrospun Fibers.

In diabetic ulcers, an increased secretion of human neutrophil elastase (HNE) and bacterial infections play crucial roles in hindering healing. Considering that, the present study proposed the development of multi-action polycaprolactone (PCL)/polyethylene glycol (PEG) electrospun fibers incorporating elastase-targeting peptides, AAPV and WAAPV, via blending. Characterization confirmed WAAPV's efficacy in regulating proteolytic enzymes by inhibiting HNE. The engineered fibers, particularly those containing PEG, exhibited optimal wettability but an accelerated degradation that was mitigated with the peptide's inclusion, thus promoting a sustained peptide release over 24 h. Peptide loading was verified indirectly through thermal stability and hydration capacity studies (hydrophobic bonding between PCL and WAAPV and hydrophilic affinities between PCL/PEG and AAPV) and determined at ≈51.1 µg/cm2 and ≈46.0 µg/cm2 for AAPV and ≈48.5 µg/cm2 and ≈51.3 µg/cm2 for WAAPV, respectively, for PCL and PCL/PEG. Both AAPV and WAAPV effectively inhibited HNE, with PEG potentially enhancing this effect by interacting with the peptides and generating detectable peptide-PEG complexes (≈10% inhibition with PCL + peptide fibers after 6 h of incubation, and ≈20% with PCL/PEG + peptide fibers after 4 h incubation). Peptide-loaded fibers demonstrated antibacterial efficacy against Staphylococcus aureus (up to ≈78% inhibition) and Escherichia coli (up to ≈66% inhibition), with peak effectiveness observed after 4 and 2 h of incubation, respectively. This study provides initial insights into the WAAPV's potential for inhibiting HNE and bacteria activities, showing promise for applications in diabetic ulcer management.

In Silico, In Vitro and Ex Vivo Evaluation of the Antihyperglycaemic, Antioxidant and Cytotoxic Properties of Coccinia grandis L. Leaf Extract.

Research background: Coccinia grandis L. is traditionally used for the treatment of diabetes mellitus. Since the scientific evidence and mechanism of action have not yet been extensively investigated, this study aims to evaluate the antidiabetic and cytotoxic effects together with the optimisation and development of a scale-up process design for higher yields of bioactive phytocompounds from C. grandis. Experimental approach: The in silico study was conducted to predict the binding affinity of phytocompounds of C. grandis for α-amylase and α-glucosidase enzymes involved in the pathophysiology of diabetes with pharmacokinetic assessment. Response surface methodology was used to determine the optimum total phenolic content (TPC), total flavonoid content (TFC), total tannin content (TTC) and antioxidant activities (DPPH and FRAP) in 17 different experimental runs in which the parameters of microwave-assisted extraction such as temperature (50-70 °C), power (400-1000 W) and time (15-45 min) were varied. The phytocompounds were purified and identified using column chromatography, thin-layer chromatography (TLC), UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR) and liquid chromatography-mass spectrometry (LC-MS). The in vitro antidiabetic activity was determined by α-amylase and α-glucosidase enzymatic inhibitory assays, while cytotoxic investigations were done by measuring haemolytic activity, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and chorioallantoic membrane (CAM) assays. Results and conclusions: The reported major bioactive compounds have shown an excellent binding affinity for α-amylase and α-glucosidase enzymes in the range of -14.28 to -36.12 kJ/mol with good pharmacokinetic properties and toxicities ranging from low to medium. The bioactive constituents such as total phenols, total flavonoids, total tannins and antioxidant activities such as DPPH and FRAP were found to be high and dependent on the optimised microwave-assisted extraction parameters such as temperature, time and power: 55 °C, 45 min and 763 W, respectively. Sixteen compounds were identified by FTIR and LC-MS spectra in the plant sample after preliminary identification, purification and TLC. The percentage of enzyme inhibition depended on the concentration of the extract (7.8-125.0 µg/mL) and was higher than that of acarbose. The haemolytic activity was in accordance with ISO standards and low toxicity was observed in the MTT and CAM assays in the range of 7.8-125.0 µg/mL, suggesting its potential use as an antidiabetic drug and for functional food development. Novelty and scientific contribution: The results of the study open up new opportunities for researchers, scientists and entrepreneurs in the food and pharmaceutical sectors to develop antidiabetic foods and medicines that help diabetics to better control their condition and maintain overall health.

Phytochemical composition, antioxidant, antibacterial, and enzyme inhibitory activities of organic extracts from flower buds of Cleistocalyx operculatus (Roxb.) Merr. et Perry.

Cleistocalyx operculatus flower buds have been widely used in traditional medicine because of their rich content of bioactive constituents. In this study, we obtained seven solvent extracts from the flower buds and evaluated their total phenolic (TPC), flavonoid (TFC), tannin (TTC), triterpenoid saponin (TSC), and alkaloid (TAC) contents. We assessed antioxidant activities using the DPPH assay and also looked at antimicrobial and enzyme inhibitory effects. The water extract possessed the highest TPC (328.9 mg GAE/g extract), followed by ethanol, methanol, and hexane extracts (85.4-101.5 mg GAE/g extract). Chloroform, butanol, ethyl acetate, and ethanol extracts had high TSCs (245.4-287.2 mg OAE/g extract). The hexane extract was richest in TTC and TFC (32.7 mg CE/g extract and 81.1 mg QE/g extract, respectively). Ethanol and methanol extracts exhibited the strongest antioxidant activities (IC50 values of 25.2 and 30.3 µg/ml, respectively), followed by the water extract (IC50 of 40.2 µg/ml). The hexane extract displayed the most growth-inhibitory activity against Helicobacter pylori ATCC51932 and ATCC43504 strains and Salmonella enterica serovar Typhimurium ATCC13311 (MIC values of 0.06, 0.13, and 0.4 mg/ml, respectively). Moreover, the hexane extract revealed the strongest inhibition of H. pylori urease activity (IC50 of 4.51 µg/ml), whereas the water and methanol extracts had potent inhibitory effects on α-glucosidase activity (IC50 values of 9.9 and 15.1 µg/ml, respectively). These flower bud extracts could be used for health protection, especially in preventing bacterial infections and inhibiting enzymes associated with various human diseases. Further investigation into the application of C. operculatus flower buds in the food and pharmaceutical industries is necessary.

The molecular determinants of calcium ATPase inhibition by curcuminoids.

The natural product curcumin and some of its analogs are known inhibitors of the transmembrane enzyme sarco/endoplasmic reticulum calcium ATPase (SERCA). Despite their widespread use, the curcuminoids' binding site in SERCA and their relevant interactions with the enzyme remain elusive. This lack of knowledge has prevented the development of curcuminoids into valuable experimental tools or into agents of therapeutic value. We used the crystal structures of SERCA in its E1 conformation in conjunction with computational tools such as docking and surface screens to determine the most likely curcumin binding site, along with key enzyme/inhibitor interactions. Additionally, we determined the inhibitory potencies and binding affinities for a small set of curcumin analogs. The predicted curcumin binding site is a narrow cleft in the transmembrane section of SERCA, close to the transmembrane/cytosol interface. In addition to pronounced complementarity in shape and hydrophobicity profiles between curcumin and the binding pocket, several hydrogen bonds were observed that were spread over the entire curcumin scaffold, involving residues on several transmembrane helices. Docking-predicted interactions were compatible with experimental observations for inhibitory potencies and binding affinities. Based on these findings, we propose an inhibition mechanism that assumes that the presence of a curcuminoid in the binding site arrests the catalytic cycle of SERCA by preventing it from converting from the E1 to the E2 conformation. This blockage of conformational change is accomplished by a combination of steric hinderance and hydrogen-bond-based cross-linking of transmembrane helices that require flexibility throughout the catalytic cycle.

Regulation of NS5B Polymerase Activity of Hepatitis C Virus by Target Specific Phytotherapeutics: An In-Silico Molecular Dynamics Approach.

Chronic hepatitis caused by the hepatitis C virus (HCV) is closely linked with the advancement of liver disease. The research hypothesis suggests that the NS5B enzyme (non-structural 5B protein) of HCV plays a pivotal role in facilitating viral replication within host cells. Hence, the objective of the present investigation is to identify the binding interactions between the structurally diverse phytotherapeutics and those of the catalytic residue of the target NS5B polymerase protein. Results of our docking simulations reveal that compounds such as arjunolic acid, sesamin, arjungenin, astragalin, piperic acid, piperidine, piperine, acalyphin, adhatodine, amyrin, anisotine, apigenin, cuminaldehyde, and curcumin exhibit a maximum of three interactions with the catalytic residues (Asp 220, Asp 318, and Asp 319) present on the Hepatitis C virus NS5B polymerase of HCV. Molecular dynamic simulation, particularly focusing on the best binding lead compound, arjunolic acid (-8.78 kcal/mol), was further extensively analyzed using RMSD, RMSF, Rg, and SASA techniques. The results of the MD simulation confirm that the NS5B-arjunolic acid complex becomes increasingly stable from 20 to 100 ns. The orientation of both arjunolic acid and sofosbuvir triphosphate (standard) within the active site was investigated through DCCM, PCA, and FEL analysis, indicating highly stable interactions of the lead arjunolic acid with the catalytic region of the NS5B enzyme. The findings of our current investigation suggest that bioactive therapeutics like arjunolic acid could serve as promising candidates for limiting the NS5B polymerase activity of the hepatitis C virus, offering hope for the future of HCV treatment.

Attenuation of adjuvant-induced arthritis with carnosic acid by inhibiting mPGES-1, COX-2, and bone loss in male SD rats.

OBJECTIVE: Rheumatoid arthritis (RA), a chronic inflammatory disease, is characterized by joint swelling, cartilage erosion, and bone destruction. This study investigated the therapeutic efficacy of Carnosic acid (CA), a natural compound with anti-inflammatory and antioxidant properties, in an adjuvant-induced arthritis model. METHODS: Paw swelling and arthritis index were measured. Oxidative stress markers, including lipid peroxidation and antioxidant enzyme levels, were assessed. Synovial tissue was analyzed for pro-inflammatory markers using real-time Q-PCR and Western blotting. The expression of mPGES-1 was determined by Western blotting. Peripheral neuropathic pain was assessed using cold and mechanical allodynia tests. Bone loss was quantitatively assessed through microcomputed tomography (µCT) scanning of femurs and X-ray radiography. Indomethacin-induced gastric ulcers were evaluated. Molecular docking studies were conducted to analyze the binding affinity of CA to mPGES-1. RESULTS: The CA treatment not only demonstrated a significant reduction in joint inflammation and paw swelling but also mitigated oxidative stress and improved the antioxidant defence system. CA inhibited microsomal prostaglandin E synthase-1 (mPGES-1) expression and the expression of pro-inflammatory molecules such as inducible nitric oxide synthase (iNOS) and cyclooxygenases-2 (COX-2), thus attenuating the arthritis symptoms without severe gastrointestinal side effects. Additionally, it inhibited the expression of pro-inflammatory molecules such as iNOS and COX-2, contributing to the reduction of arthritis symptoms. Notably, CA treatment prevented the common side effects of traditional RA treatments like corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs), including weight loss, bone degradation, and gastric ulcers. CONCLUSIONS: These findings suggest that CA, through specific enzyme inhibition, offers a compelling alternative therapeutic approach for RA. Further research is warranted to explore the potential of CA in other arthritis models and its suitability for human RA treatment.

CA significantly reduces inflammation in FCA induced arthritis model.CA treatment inhibits key pro-inflammatory molecules, including mPGES-1 and COX-2In silico docking studies confirm the affinity of CA to mPGES-1.CA prevents bone loss and avoids side effects seen with standard treatments.Antioxidant properties of CA counteract oxidative stress related to chronic inflammation.

Novel mode of kafirin modification using combination of enzyme and thermal treatment to expand its food application.

Kafirin in sorghum inhibits starch digestion and exhibits antioxidant properties, however its potential in food industry remains unexplored. Therefore, the study was aimed to explore and improve the potential of kafirin as natural carbohydrate blocker using papain (6 NFU/mL) and/or infrared treatment (220 °C/3 min). Results indicated that the combined treatment, PIR (infrared + papain) is the most efficient treatment to modify kafirin. PIR generated a new ∼37 kDa high molecular weight moiety in kafirin with a crystal size of 157.44 Å. All samples showed superior antioxidant activity post-treatments, with PIR exhibiting highest scavenging activity from 31.09 to 82.97%, 15.09 to 42.82%, and 25.92 to 38.58% for DPPH, FRAP, and ABTS, respectively. PIR-modified kafirin limited malondialdehyde production, and increased α-amylase and α-glucosidase inhibition. Incorporation of 7.5% kafirin in corn starch increased resistant starch from 5.09 to 21.04% after cooking, which suggests potential of kafirin in development of diabetic-friendly food formulations.

Natural flavonoids as promising lactate dehydrogenase A inhibitors: Comprehensive in vitro and in silico analysis.

The inhibitory potential of 17 flavonoids on lactate dehydrogenase A (LDHA), a key enzyme in the downstream process of aerobic glycolysis in cancer cells, is investigated. Fisetin exhibited excellent inhibitory activity (IC50 = 0.066 µM). Quercetin 3-ß-D-glucoside, quercetin 3-galactoside, luteolin, neoeriocitrin, and luteolin 7-O-ß-D-glucoside showed good inhibitory activity (IC50 = 1.397-15.730 µM). Biochanin A, baicalein, quercetin, scutellarein-7-glucuronide, diosmetin, baicalein 7-O-ß-D-glucuronide, and apigenin 7-apioglucoside demonstrated moderate inhibitory activity (IC50 = 33.007-86.643 µM). Eriodictyol, quercetin 7-O-ß-D-glucoside, apigenin 7-O-ß-D-glucoside, and epicatechin were inactive. The Lineweaver-Burk plot showed that fisetin competitively inhibits NADH binding (Ki = 0.024 µM). Ki values for other compounds were calculated using the Cheng-Prusoff equation (Ki = 0.2799-2.1661 µM). The study revealed that the inhibitory effect of flavonoids varies with the number and position of OH groups and bound sugars. Molecular docking analyses indicated that flavonoids exhibited strong interactions with the NADH binding site of LDHA through hydrophobic interactions and hydrogen bonds. Molecular dynamic simulations tested the stability of the fisetin-LDHA complex over 100 ns and showed fisetin's high binding affinity to LDHA, maintaining strong hydrogen bonds. The binding energy of fisetin with LDHA was -33.928 kcal/mol, indicating its effectiveness as an LDHA inhibitor. Consequently, flavonoids identified as strong inhibitors could be potential cancer treatment sources through LDHA inhibition.

N α -acetyl-L-ornithine deacetylase from Escherichia coli and a ninhydrin-based assay to enable inhibitor identification.

Bacteria are becoming increasingly resistant to antibiotics, therefore there is an urgent need for new classes of antibiotics to fight antibiotic resistance. Mammals do not express N ɑ -acetyl-L-ornithine deacetylase (ArgE), an enzyme that is critical for bacterial survival and growth, thus ArgE represents a promising new antibiotic drug target, as inhibitors would not suffer from mechanism-based toxicity. A new ninhydrin-based assay was designed and validated that included the synthesis of the substrate analog N 5, N 5-di-methyl N α-acetyl-L-ornithine (kcat/Km = 7.32 ± 0.94 × 104 M-1s-1). This new assay enabled the screening of potential inhibitors that absorb in the UV region, and thus is superior to the established 214 nm assay. Using this new ninhydrin-based assay, captopril was confirmed as an ArgE inhibitor (IC50 = 58.7 µM; Ki = 37.1 ± 0.85 µM), and a number of phenylboronic acid derivatives were identified as inhibitors, including 4-(diethylamino)phenylboronic acid (IC50 = 50.1 µM). Selected inhibitors were also tested in a thermal shift assay with ArgE using SYPRO Orange dye against Escherichia coli ArgE to observe the stability of the enzyme in the presence of inhibitors (captopril Ki = 35.9 ± 5.1 µM). The active site structure of di-Zn EcArgE was confirmed using X-ray absorption spectroscopy, and we reported two X-ray crystal structures of E. coli ArgE. In summary, we describe the development of a new ninhydrin-based assay for ArgE, the identification of captopril and phenylboronic acids as ArgE inhibitors, thermal shift studies with ArgE + captopril, and the first two published crystal structures of ArgE (mono-Zn and di-Zn).

Metabolic profiling and enzyme inhibitory activity of the essential oil of citrus aurantium fruit peel.

BACKGROUND: Bitter orange (Citrus aurantium) is a fruiting shrub native to tropical and subtropical countries around the world and cultivated in many regions due to its nutraceutical value. The current study investigated the metabolic profiling and enzyme inhibitory activities of volatile constituents derived from the C. aurantium peel cultivated in Egypt by three different extraction methods. METHODS: The volatile chemical constituents of the peel of C. aurantium were isolated using three methods; steam distillation (SD), hydrodistillation (HD), and microwave-assisted hydrodistillation (MAHD), and then were investigated by GC-MS. The antioxidant potential was evaluated by different assays such as DPPH, ABTS, FRAP, CUPRAC, and phosphomolybdenum and metal chelating potential. Moreover, the effect of enzyme inhibition of the three essential oils was tested using BChE, AChE, tyrosinase, glucosidase, as well as amylase assays. RESULTS: A total of six compounds were detected by GC/MS analysis. The major constituent obtained by all three extraction methods was limonene (98.86% by SD, 98.68% by HD, and 99.23% by MAHD). Differences in the composition of the compounds of the three oils were observed. The hydrodistillation technique has yielded the highest number of compounds, notably two oxygenated monoterpenes: linalool (0.12%) and α-terpineol acetate (0.1%). CONCLUSION: In our study differences in the extraction methods of C. aurantium peel oils resulted in differences in the oils' chemical composition. Citrus essential oils and their components showed potential antioxidant, anticholinesterase, antimelanogenesis, and antidiabetic activities. The presence of linalool and α-terpineol acetate may explain the superior activity observed for the oil isolated by HD in both radical scavenging and AChE inhibition assays, as well as in the enzyme inhibition assays.

Characterization of structure of peptidyl-tRNA hydrolase from Enterococcus faecium and its inhibition by a pyrrolinone compound.

In bacteria, peptidyl-tRNA hydrolase (Pth, E.C. 3.1.1.29) is a ubiquitous and essential enzyme for preventing the accumulation of peptidyl-tRNA and sequestration of tRNA. Pth is an esterase that cleaves the ester bond between peptide and tRNA. Here, we present the crystal structure of Pth from Enterococcus faecium (EfPth) at a resolution of 1.92 Å. The two molecules in the asymmetric unit differ in the orientation of sidechain of N66, a conserved residue of the catalytic site. Enzymatic hydrolysis of substrate α-N-BODIPY-lysyl-tRNALys (BLT) by EfPth was characterized by Michaelis-Menten parameters KM 163.5 nM and Vmax 1.9 nM/s. Compounds having pyrrolinone scaffold were tested for inhibition of Pth and one compound, 1040-C, was found to have IC50 of 180 nM. Antimicrobial activity profiling was done for 1040-C. It exhibited equipotent activity against drug-susceptible and resistant S. aureus (MRSA and VRSA) and Enterococcus (VSE and VRE) with MICs 2-8 µg/mL. 1040-C synergized with gentamicin and the combination was effective against the gentamicin resistant S. aureus strain NRS-119. 1040-C was found to reduce biofilm mass of S. aureus to an extent similar to Vancomycin. In a murine model of infection, 1040-C was able to reduce bacterial load to an extent comparable to Vancomycin.

Synthesis and characterization of novel bis(thiosemicarbazone) complexes and investigation of their acetylcholinesterase and glutathione S-transferase activities with in silico and in vitro studies.

In this study, firstly, bis(thiosemicarbazone) ligand [L: 2,2'-(2-(2-(4-methoxyphenyl)hydrazineylidene)cyclohexane-1,3-diylidene)bis(hydrazine-1-carbothioamide)] was synthesized by the condensation reaction of thiosemicarbazide and ketone compound (2-(2-(4-methoxyphenyl)hydrazone)cyclohexane-1,3-dione). The metal complexes were synthesized by the reaction of obtained ligand (L) with CuCl2·2H2O, NiCl2·6H2O, CoCl2·6H2O, and MnCl2·4H2O salts. The structures of synthesized ligand and their complexes were characterized using elemental analysis, IR, UV-Vis, 1H-NMR spectra, 13C-NMR spectra, magnetic susceptibility, mass spectra (LC-MS), thermogravimetry analysis-differential thermal analysis (TGA-DTA), and differential scanning calorimetry techniques. According to the results of the analysis, square plane geometry was suggested for Cu and Co complexes. However, the structures of Ni and Mn complexes were in agreement with octahedral geometry. Molecular docking analysis and pharmacological potential of the compound were evaluated to determine the inhibitory potential against acetylcholinesterase (AChE) and Glutathione-S-transferases (GST) enzymes. The compound exhibited strong binding/docking indices of - 5.708 and - 5.928 kcal/mol for the respective receptors. In addition, L-Ni(II) complex was found to be the most effective inhibitor for AChE enzyme with a Ki value of 0.519. However, with a Ki value of 1.119, L-Cu(II) complex was also found to be an effective inhibitor for the GST enzyme.

Antioxidant, antibacterial, enzyme inhibition and fluorescence characteristics of unsymmetrical thiourea derivatives.

A series of six unsymmetrical thiourea derivatives, namely 1-cyclohexyl-3-(pyridin-2-yl) thiourea (1), 1-cyclohexyl-3-(3-methylpyridin-2-yl)thiourea (2), 1-cyclohexyl-3-(2,4-dimethylphenyl) thiourea (3), 1-(4-chlorophenyl)-3-cyclohexylthiourea (4), 1-(3-methylpyridin-2-yl)-3-phenylthiourea (5), and 1-(3-chlorophenyl)-3-phenylthiourea (6), were successfully synthesized via reaction between different amines with isothiocyanates under a non-catalytic environment. Structural elucidation of compounds (1-6) was performed using FT-IR and NMR (1H and 13C) spectroscopy. The infrared spectra displayed characteristic stretching vibrations, while the 13C NMR chemical shifts of the thiourea moiety (C[bond, double bond]S) were observed in the range of 179.1-181.4 ppm. The antioxidative and antimicrobial properties of the compounds were assessed, as well as their inhibitory effects on acetylcholinesterase and butyrylcholinesterase were evaluated. In order to analyze the fluorescence characteristics of each compound (1-6), the excitation (λex) and emission (λem) wavelengths were scanned within the range of 250-750 nm, with the solvent blank serving as a standard. It was observed that when dissolved in acetone, toluene, tetrahydrofuran, and ethyl acetate, these compounds exhibited emission peaks ranging from 367 to 581 nm and absorption peaks ranging from 275 to 432 nm.

Influence of extraction solvents on the chemical constituents and biological activities of Astragalus aduncus from Turkey flora: In vitro and in silico insights.

The n-hexane, ethyl acetate, ethanol, ethanol/water (70% ethanol), and water extracts of Astragalus aduncus aerial parts were investigated for their antioxidant potential, enzyme inhibition activity (anti-acetylcholinesterase [AChE], anti-butyrylcholinesterase [BChE], antityrosinase, antiamylase, and antiglucosidase) and antiproliferative effect (against colon adenocarcinoma cell line [HT-29], gastric cancer cell line [HGC-27], prostate carcinoma cell line [DU-145], breast adenocarcinoma cell line [MDA-MB-231], and cervix adenocarcinoma cell line [HeLa]). In addition, the phytochemical profile of the extracts was evaluated using validated spectrophotometric and high-pressure liquid chromatography-electrospray ionization/tandem mass spectroscopy methods. Generally, the 70% ethanol extract demonstrated the strongest antioxidant properties, and it was the richest source of total phenolic constituents. Our findings indicated that the ethyl acetate extract was the most potent BChE inhibitor (11.44 mg galantamine equivalents [GALAE]/g) followed by the ethanol extract (8.51 mg GALAE/g), while the ethanol extract was the most promising AChE inhibitor (3.42 mg GALAE/g) followed by the ethanol/water extract (3.17 mg GALAE/g). Excellent tyrosinase inhibitory activity (66.25 mg kojic acid equivalent/g) was observed in ethanol/water extracts of the aerial part of A. aduncus. Тhese results showed that the most cytotoxic effects were exhibited by the ethyl acetate extract against HGC-27 cells (IC50: 36.76 µg/mL), the ethanol extract against HT-29 cells (IC50: 30.79 µg/mL), and the water extract against DU-145 cells (IC50: 37.01 µg/mL). A strong correlation was observed between the highest total flavonoid content and the highest content of individual compounds in the ethanol extract, including rutin, hyperoside, isoquercitrin, delphinidin-3,5-diglucoside (delphinidin-3,5-O-diglucoside), and kaempferol-3-glucoside (kaempferol-3-O-glucoside). In the present study, the A. aduncus plant was considered a new source of antioxidants, enzyme inhibitors, and anticancer agents and could be used as a future health-benefit natural product.

Investigation into the Phytochemical Composition, Antioxidant Properties, and In-Vitro Anti-Diabetic Efficacy of Ulva lactuca Extracts.

In this research, the chemical compositions of various extracts obtained from Ulva lactuca, a type of green seaweed collected from the Nador lagoon in the northern region of Morocco, were compared. Their antioxidant and anti-diabetic properties were also studied. Using GC-MS technology, the fatty acid content of the samples was analyzed, revealing that palmitic acid, eicosenoic acid, and linoleic acid were the most abundant unsaturated fatty acids present in all samples. The HPLC analysis indicated that sinapic acid, naringin, rutin, quercetin, cinnamic acid, salicylic acid, apigenin, flavone, and flavanone were the most prevalent phenolic compounds. The aqueous extract obtained by maceration showed high levels of polyphenols and flavonoids, with values of 379.67 ± 0.09 mg GAE/g and 212.11 ± 0.11 mg QE/g, respectively. This extract also exhibited an impressive ability to scavenge DPPH radicals, as indicated by its IC50 value of 0.095 ± 0.12 mg/mL. Additionally, the methanolic extract obtained using the Soxhlet method demonstrated antioxidant properties by preventing ß-carotene discoloration, with an IC50 of 0.087 ± 0.14 mg/mL. Results from in-vitro studies showed that extracts from U. lactuca were able to significantly inhibit the enzymatic activity of α-amylase and α-glucosidase. Among the various extracts, methanolic extract (S) has been identified as the most potent inhibitor, exhibiting a statistically similar effect to that of acarbose. Furthermore, molecular docking models were used to evaluate the interaction between the primary phytochemicals found in these extracts and the human pancreatic α-amylase and α-glucosidase enzymes. These findings suggest that U. lactuca extracts contain bioactive substances that are capable of reducing enzyme activity more effectively than the commercially available drug, acarbose.

Effect of UV LED and Pulsed Light Treatments on Polyphenol Oxidase Activity and Escherichia coli Inactivation in Apple Juice.

Enzymatic browning in fruits and vegetables, driven by polyphenol oxidase (PPO) activity, results in color changes and loss of bioactive compounds. Emerging technologies are being explored to prevent this browning and ensure microbial safety in foods. This study assessed the effectiveness of pulsed light (PL) and ultraviolet light-emitting diodes (UV-LED) in inhibiting PPO and inactivating Escherichia coli ATTC 25922 in fresh apple juice (Malus domestica var. Red Delicious). Both treatments' effects on juice quality, including bioactive compounds, color changes, and microbial inactivation, were examined. At similar doses, PL-treated samples (126 J/cm2) showed higher 2,2- diphenyl-1-picrylhydrazyl inhibition (9.5%) compared to UV-LED-treated samples (132 J/cm2), which showed 1.06%. For microbial inactivation, UV-LED achieved greater E. coli reduction (>3 log cycles) and less ascorbic acid degradation (9.4% ± 0.05) than PL. However, increasing PL doses to 176 J/cm2 resulted in more than 5 log cycles reduction of E. coli, showing a synergistic effect with the final temperature reached (55 °C). The Weibull model analyzed survival curves to evaluate inactivation kinetics. UV-LED was superior in preserving thermosensitive compounds, while PL excelled in deactivating more PPO and achieving maximal microbial inactivation more quickly.

Combining chemical profiles and biological abilities of different extracts from Tanacetum nitens ( Boiss. & Noë) Grierson using network pharmacology.

Tanacetum nitens ( Boiss. & Noë)  Grierson is an aromatic perennial herb used in Turkish traditional medicine to treat headache, fever, and skin diseases. This study aimed to investigate the chemical composition, antioxidant, enzyme inhibition, and cytotoxic properties of T. nitens aerial parts. Organic solvent extracts were prepared by sequential maceration in hexane, dichloromethane, ethyl acetate, and methanol while aqueous extracts were obtained by maceration or infusion. Nuclear magnetic resonance (NMR) and LC-DAD-MS analysis allowed the identification and quantification of different phytoconstituents including parthenolide, tanacetol B, tatridin B, quinic acid derivatives, ß-sitosterol, and glycoside derivatives of quercetin and luteolin. The type and amount of these phytochemicals recovered by each solvent were variable and significant enough to impact the biological activities of the plant. Methanolic and aqueous extracts displayed the highest scavenging and ions-reducing properties while the dichloromethane and ethyl acetate extracts exerted the best total antioxidant activity and metal chelating power. Results of enzyme inhibition activity showed that the hexane, ethyl acetate, and dichloromethane extracts had comparable anti-acetylcholinesterase activity and the latter extract revealed the highest anti-butyrylcholinesterase activity. The best α-amylase and α-glucosidase inhibition activities were obtained from the hexane extract. The dichloromethane and ethyl acetate extracts exhibited the highest cytotoxic effect against the prostate carcinoma DU-145 cells. In conclusion, these findings indicated that T. nitens can be a promising source of biomolecules with potential therapeutic applications.

Cell type-specific control and post-translational regulation of specialized metabolism: opening new avenues for plant metabolic engineering.

Although plant metabolic engineering enables the sustainable production of valuable metabolites with many applications, we still lack a good understanding of many multi-layered regulatory networks that govern metabolic pathways at the metabolite, protein, transcriptional and cellular level. As transcriptional regulation is better understood and often reviewed, here we highlight recent advances in the cell type-specific and post-translational regulation of plant specialized metabolism. With the advent of single-cell technologies, we are now able to characterize metabolites and their transcriptional regulators at the cellular level, which can refine our searches for missing biosynthetic enzymes and cell type-specific regulators. Post-translational regulation through enzyme inhibition, protein phosphorylation and ubiquitination are clearly evident in specialized metabolism regulation, but not frequently studied or considered in metabolic engineering efforts. Finally, we contemplate how advances in cell type-specific and post-translational regulation can be applied in metabolic engineering efforts in planta, leading to optimization of plants as metabolite production vehicles.