Antioxidant,Antimicrobial Activities and Characterization of Polyphenol-Enriched Extract of Egyptian Celery (Apium graveolens L., Apiaceae) Aerial Parts via UPLC/ESI/TOF-MS

Medicinal plant extracts are increasingly considered a major source of innovative medications and healthcare products. This study focused on preparing a polyphenol enriched water extract of Egyptian celery “Apium graveolens L., Apiaceae” aerial parts (TAE) in an endeavor to accentuate its antioxidant capacity as well as its antimicrobial activity. (TAE) of celery was partitioned against different organic solvents to yield dichloromethane (DCM), ethyl acetate (EAC), and butanol (BUOH) fractions. (TAE) and the organic fractions thereof besides the remaining mother liquor (ML) were all screened for their antioxidant capacity using various protocols viz. monitoring the reducing amplitudes for ferric ions (FRAP), and radical scavenging potentials of oxygen (ORAC), 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and metal chelation assays. The examination procedure revealed both (TAE) extract and (DCM) fraction, to pertain the highest antioxidant potentials, where the IC₅₀ of the (TAE) using ABTS and metal chelation assays were ca. 34.52 ± 3.25 and 246.6 ± 5.78 µg/mL, respectively. The (DCM) fraction recorded effective results using the FRAP, ORAC, and DPPH assays ca. 233.47 ± 15.14 and 1076 ± 25.73 μM Trolox equivalents/mg sample and an IC₅₀ 474.4 ± 19.8 µg/mL, respectively. Additionally, both (TAE) and (DCM) fraction exerted antimicrobial activities recording inhibition zones (mm) (13.4 ± 1.5) and (12.0 ± 1.0) against Staphylococcus aureus and (11.0 ± 1.2) and (10.0 ± 1.3) against Escherichia coli, respectively, with no anti-fungal activity. Minimum inhibitory concentration (MIC) of (TAE) and (DCM) fraction were 1250 and 2500 µg/mL, respectively. UPLC/ESI/TOF-MS unveiled the chemical profile of both (TAE) and (DCM) fraction to encompass a myriad of active polyphenolic constituents including phenylpropanoids, coumarins, apigenin, luteolin, and chrysoeriol conjugates.     

Photochemical Approach to the Cyclohepta[b]indole Scaffold by Annulative Two-Carbon Ring-Expansion

We report on the implementation of the concept of a photochemically elicited two-carbon homologation of a π-donor–π-acceptor substituted chromophore by triple-bond insertion. Implementing a phenyl connector between the slide-in module and the chromophore enabled the synthesis of cylohepta[b]indole-type building blocks by a metal-free annulative one-pot two-carbon ring expansion of the five-membered chromophore. Post-irradiative structural elaboration provided founding members of the indolo[2,3-d]tropone family of compounds. Control experiments in combination with computational chemistry on this multibond reorganization process founded the basis for a mechanistic hypothesis.     

Purification and Biochemical Characterization of a New Protease Inhibitor from Conyza dioscoridis with Antimicrobial,Antifungal and Cytotoxic Effects

The main objective of the current study was the extraction, purification, and biochemical characterization of a protein protease inhibitor from Conyza dioscoridis. Antimicrobial potential and cytotoxic effects were also examined. The protease inhibitor was extracted in 0.1 M phosphate buffer (pH 6–7). Then, the protease inhibitor, named PDInhibitor, was purified using ammonium sulfate precipitation followed by filtration through a Sephadex G-50 column and had an apparent molecular weight of 25 kDa. The N-terminal sequence of PDInhibitor showed a high level of identity with those of the Kunitz family. PDInhibitor was found to be active at pH values ranging from 5.0 to 11.0, with maximal activity at pH 9.0. It was also fully active at 50 °C and maintained 90% of its stability at over 55 °C. The thermostability of the PDInhibitor was clearly enhanced by CaCl₂ and sorbitol, whereas the presence of Ca²⁺ and Zn²⁺ ions, Sodium taurodeoxycholate (NaTDC), Sodium dodecyl sulfate (SDS), Dithiothreitol (DTT), and β-ME dramatically improved the inhibitory activity. A remarkable affinity of the protease inhibitor with available important therapeutic proteases (elastase and trypsin) was observed. PDInhibitor also acted as a potent inhibitor of commercial proteases from Aspergillus oryzae and of Proteinase K. The inhibitor displayed potent antimicrobial activity against gram+ and gram- bacteria and against fungal strains. Interestingly, PDInhibitor affected several human cancer cell lines, namely HCT-116, MDA-MB-231, and Lovo. Thus, it can be considered a potentially powerful therapeutic agent.     

Anti‐tumor platinum (IV) complexes bearing the anti‐inflammatory drug naproxen in the axial position

The role of inflammation in cancer generation is gaining importance in the field of cancer research. The chemo‐anti‐inflammatory strategy that involves using non‐steroidal anti‐inflammatory drug compounds as effective anti‐tumor agents is being acceded globally. In the present study, seven new Pt (IV) complexes based on cisplatin, carboplatin and oxaliplatin scaffold bearing the anti‐inflammatory drug naproxen in the axial position were synthesized and characterized by elemental analysis, ESI‐MS, Fourier transform‐infrared, ¹H‐ and ¹⁹⁵Pt‐NMR spectroscopy. The reduction behavior in the presence of ascorbic acid was studied using high‐performance liquid chromatography. The cytotoxicity against two human breast cell lines and the anti‐inflammatory properties were evaluated. All the complexes are able to promote a comparable activity, with average three‐ and 13‐fold more cytotoxic than cisplatin against MCF7 and MDA‐MB‐231 cell lines, respectively. The complexes show remarkable anti‐inflammatory effects, which indicated their potential in treating cancer associated with inflammation and reducing side‐effects of chemotherapy.     

X-ray structure of host-guest nanosized organotin supramolecular coordination polymer based on cobalt cyanide and quinoxaline as an efficient catalyst for treatment of waste water

New host-guest supramolecular coordination polymer catalyst ³_∞[Co(μ²CN)₅(CN)(μ²-Me₃Sn)₂(Me₃Sn)(H₂O)(qox)], SCP1 (qox = quinoxaline) has been synthesized and characterized by single crystal X-ray diffraction, FT-IR, UV/Visible and fluorescence spectra, thermal and elemental analyses. The tin atoms act as bridges connecting the Co (CN)₆ building blocks. The structure of SCP1 exhibits an unusual self-coordinated host-guest 3D network with qox as guest molecule. Also, the nanosized1^\ was prepared under ultrasonic irradiation while the morphological features of both were examined by TEM and SEM. SCP1 and nanosized1^\ are used as heterogeneous catalysts for removal of toxic dyes under UV and ultrasonic irradiation. The results show high effectively decolorized of indigo carmine dye (IC) without generation of any hazardous wastes or byproducts. The reaction is first order with respect to IC, while the factors affecting the rate constant of the degradation reaction are investigated. Mineralization of IC was investigated by IR and UV spectra. The trapping experiments were carried out to determine the role of active species used for degradation of the dye. The activation parameters of the reaction have been estimated and a possible mechanism of degradation was proposed and discussed in detail.     

124I Radiolabeling of a AuIII-NHC Complex for In Vivo Biodistribution Studies

Au^III complexes with N-heterocyclic carbene (NHC) ligands have shown remarkable potential as anticancer agents, yet their fate in vivo has not been thoroughly examined and understood. Reported herein is the synthesis of new Au^III-NHC complexes by direct oxidation with radioactive [¹²⁴I]I₂ as a valuable strategy to monitor the in vivo biodistribution of this class of compounds using positron emission tomography (PET). While in vitro analyses provide direct evidence for the importance of Au^III-to-Au^I reduction to achieve full anticancer activity, in vivo studies reveal that a fraction of the Au^III-NHC prodrug is not immediately reduced after administration but able to reach the major organs before metabolic activation.     

Synthesis of graphitic carbon nitride-based photocatalysts for hydrogen evolution under visible light

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