Volume 79, Issue 3-4

Garcinia mangostana fruits are used traditionally for inflammatory skin conditions, including acne. In this study, an in silico approach was employed to predict the interactions of G. mangostana xanthones and benzophenones with three proteins involved in the pathogenicity of acne, namely the human JNK1, Cutibacterium acnes KAS III and exo-β-1,4-mannosidase. Molecular docking analysis was performed using Autodock Vina. The highest docking scores and size-independent ligand efficiency values towards JNK1, C. acnes KAS III and exo-β-1,4-mannosidase were obtained for garcinoxanthone T, gentisein/2,4,6,3′,5′-pentahydroxybenzophenone and mangostanaxanthone VI, respectively. To the best of our knowledge, this is the first report of the potential of xanthones and benzophenones to interact with  C. acnes KAS III. Molecular dynamics simulations using GROMACS indicated that the JNK1-garcinoxanthone T complex had the highest stability of all ligand–protein complexes, with a high number of hydrogen bonds predicted to form between this ligand and its target. Petra/Osiris/Molinspiration (POM) analysis was also conducted to determine pharmacophore sites and predict the molecular properties of ligands influencing ADMET. All ligands, except for mangostanaxanthone VI, showed good membrane permeability. Garcinoxanthone T, gentisein and 2,4,6,3′,5′-pentahydroxybenzophenone were identified as the most promising compounds to explore further, including in experimental studies, for their anti-acne potential.

A new series of 4-nitroimidazole bearing aryl piperazines 7–16 , tetrazole 17 and 1,3,4-thiadiazole 18 derivatives was synthesized. All derivatives were screened for their anticancer activity against eight diverse human cancer cell lines (Capan-1, HCT-116, LN229, NCI–H460, DND-41, HL-60, K562, and Z138). Compound 17 proved the most potent compound of the series inhibiting proliferation of most of the selected human cancer cell lines with IC 50 values in the low micromolar range. In addition, compound 11 exhibited IC 50 values ranging 8.60–64.0 μM against a selection of cancer cell lines. These findings suggest that derivative 17 can potentially be a new lead compound for further development of novel antiproliferative agents. Additionally, 17–18 were assessed for their antibacterial and antituberculosis activity. Derivatives 17 and 18 were the most potent compounds of this series against both Staphylococcus aureus strain Wichita and a methicillin resistant strain of S. aureus (MRSA), as well as against Mycobacterium tuberculosis strain mc 2 6230. The antiviral activity of 7–18 was also evaluated against diverse viruses, but no activity was detected. The docking study of compound 17 with putative protein targets in acute myeloid leukemia had been studied. Furthermore, the molecular dynamics simulation of 17 and 18 had been investigated.

The Sceletium -type alkaloids, known for their anxiolytic and antidepressant activities, have been recently found to be biosynthesized in Narcissus cv. Hawera, which is largely used as an ornamental plant. An alkaloid fraction enriched with Sceletium -type alkaloids from the plant has shown promising antidepressant and anxiolytic activities. In the present study, qualitative and quantitative analyses of the alkaloids in the plant organs were performed during one vegetation season by GC-MS. The alkaloid pattern and total alkaloid content was found to depend strongly on the stage of development and plant organ. The alkaloid content of bulbs was found to be highest during the dormancy period and lowest in sprouting bulbs. The leaves showed the highest alkaloid content during the intensive vegetative growth and lowest during flowering. In total, 13 alkaloids were detected in the methanol extracts of Narcissus cv. Hawera, six Sceletium -type and seven typical Amaryllidaceae alkaloids. Major alkaloids in the alkaloid pattern were lycorine, 6- epi -mesembrenol, mesembrenone, sanguinine, and galanthamine. The leaves of flowering plants were found to have the highest amount of 6- epi -mesembrenol. Mesembrenone was found to be dominant alkaloid in the leaves of sprouting bulbs and in the flowers. Considering the biomass of the plant, the dormant bulbs are the best source of alkaloid fractions enriched with 6- epi -mesembrenol. The flowers and the young leaves can be used for preparation of alkaloid fractions enriched with mesembrenone. The results indicates that Narcissus cv. Hawera is an emerging source of valuable bioactive compounds and its utilization can be extended as a medicinal plant.

Soft corals, particularly Sarcophyton sp. are rich in metabolites with variety of biological activities. In this study, a pyran-based 9- exo -methylene-10-hydroxy-sarcotrocheliol ( 1 ) and 2-dehydro-4-peroxy-sarcophine ( 2 ), two new cembranoide diterpenes, were isolated together with 9-hydroxy-10,11-dehydro-sarcotrocheliol, sarcotrocheliol, sarcotrocheliol acetate, sarcophine, (+)-7 α ,8 β -dihydroxydeepoxysarcophine, (±)-sarcophytonine B, and peridinin from the organic extract of Sarcophyton glaucum collected at the coasts of Hurghada, Egypt. The structures of the new diterpenes 1–2 were identified based on cumulative analyses of HRESIMS and NMR (1D/2D NMR) spectra. The relative configurations of both compounds were verified by NOESY spectra and comparison with our recently reported analogues. The compounds showed no antimicrobial activity against a set of diverse tested microorganisms.

A novel isocoumarin was isolated from the mycelia of the dark septate endophytic fungus Phialocephala fortinii . The chemical structure was determined to be 8-hydroxy-6-methoxy-3,7-dimethyl-1 H -2-benzopyran-1-one based on mass spectrometry, 1 H-nuclear magnetic resonance (NMR), and 13 C-NMR spectroscopic analyses, including 2D-NMR experiments. The isolated compound inhibited root growth of Arabidopsis thaliana , suggesting its potential as a plant growth regulator.