Nutritional, Antioxidant, Antimicrobial, and Anticholinesterase Properties of Phyllanthus emblica: A Study Supported by Spectroscopic and Computational Investigations.

Dietary fruits and vegetables play a vital role as food and drugs and are the main sources of antioxidant defences against degenerative diseases, such as brain dysfunctions, cardiovascular diseases, immune system deteriorations, and cancers, brought on by oxidative damage. Phyllanthus emblica is a significant herbal remedy used in conventional medicine to recover lost strength and power. In this research, the potential value of Phyllanthus emblica as a food and drug is researched. The total phenolic, total flavonoid, and total tannin contents as well as the nutritional value, vitamin C, vitamin E, and mineral contents of different organs of P. emblica were evaluated. The antioxidant and antimicrobial activities of extracts and fractions of different organs of P. emblica were determined. A total of eleven flavonoids, simple phenolic, tannin-related phenolic, and tannin molecules were isolated from a hydroalcoholic extract of the leaves and fruits. The structures were identified by spectroscopic data and comparison with the literature values as gallic acid (1), naringenin 7-O-(6″-O-galloyl)-ß-D-glucopyranoside (2), 3,3'-di-O-methyl ellagic acid-4'-O-ß-d-glucopyranoside (3), 1-O-galloyl glycerol (4), 1,6-di-O-galloyl-ß-d-glucopyranoside (5), flavogallonic acid bislactone (6), corilagin (7), ethyl gallate (8), urolithin M5 (9), (E)-p-coumaroyl-1-O-ß-d-glucopyranoside (10), and 1,2,4,6-tetra-O-galloyl-ß-d-glucopyranoside (11). Among them, compounds 3 and 10 are first isolated from the plant. Molecular docking was performed to investigate the comparative interactions between positive controls (galantamine and donepezil) and selected compounds utilizing acetylcholinesterase (4EY7) as a target receptor. Results exhibited the potency of these compounds against the target receptor. In summary, P. emblica has a wealth of minerals, vitamins C and E, and polyphenolic phytochemicals that may work together to treat infectious disease, prevent and/or treat oxidative-damage-related illnesses including Alzheimer's disease.

Phytochemical and in silico studies for potential constituents from Centaurium spicatum as candidates against the SARS-CoV-2 main protease and RNA-dependent RNA polymerase.

In the present study, a new secoiridoid glycoside lisianthoside II 1, along with seven known compounds 2-8, were isolated from Centaurium spicatum L. In-silico molecular docking and molecular dynamic simulation against SARS-CoV-2 Main protease (Mpro) and RNA-dependent RNA polymerase (RdRp) were conducted. The affinity docking scores revealed that 8 is the best bound ligand to Mpro active site with binding energy of -14.9877 kcal/mol (RSMD = 1.16 Å), while 6 was the highest against RdRp (-16.9572 kcal/mol, RMSD = 1.01 Å). Moreover, the molecular dynamic simulation revealed that 8 with a (ΔG) of -7.9 kcal/mol (RMSD value of 2.6 Å) and 6 (RMSD value of 1.6 Å) and binding free energy (ΔG) of -7.1 kcal/mol achieved the highest stability over 50 ns of MDS inside the Mpro and RdRp enzyme's active site, respectively. Hence, the isolated compounds could be a good lead for development of new leads targeting COVID-19.

A New Phenolic Alkaloid from Halocnemum strobilaceum Endophytes: Antimicrobial, Antioxidant and Biofilm Inhibitory Activities.

Human infections caused by microbial biofilm formation represent a growing major health threat. A new alkaloid, 3-amino-5-(3-hydroxybutan-2-yl)-4-methylphenol, was isolated from the corn grit culture of the endophytic isolate Penicillium citrinum-314 associated with Halocnemum strobilaceum, a halophyte growing in the Egyptian marshes. The new alkaloid was identified by 1D, 2D-NMR and HR-ESI-MS-MS and given the trivial name halociline. The antioxidant, antimicrobial and antibiofilm activities were recorded. Furthermore, another known compound, 1,3,6-trihydroxy-7-methoxy-9H-xanthen-9-one, was obtained in smaller amounts and revealed a non-microbicidal 100 % reduction in biofilm formation, with an MBIC value of 62.5 µg/mL (228 µM) against Pseudomonas aeruginosa (Ferm-BAM), a FRAP value of 447.941±37.876 mM/L as well as a marked safety profile against three cancer cell lines. Through in silico molecular docking study, in the binding sites of Pseudomonas enzymes, key ligand enzyme interactions were determined to support the in vitro results.

New nitrogenous compounds from Anisotes trisulcus.

Re-investigation of the methanolic extract of Anisotes trisulcus (Forssk.) Nees aerial parts led to the isolation of two new tricyclic quinazoline alkaloids, 8-amino-7,8,9,11-tetrahydro-6H-pyrido[2,1-b]-quinazoline-2,6-diol (4) and 8-amino-3,6-dihydroxy-7,8,9-trihydro-6H-pyrido[2,1-b]quinazoline-11-one (5), and two quaternary ammonium compounds, (dimethylamino)-N-(hydroxymethyl)-N,N-dimethyl methanaminium chloride (6) and N-[(carboxyamino)methyl]-N,N-dimethyl ethanaminium chloride (7), together with three known compounds, peganine (1), vasicinone (2), and anisotine (3). The structures of these compounds were established on the basis of physical, chemical, and spectral data (UV, IR, MS, 1D and 2D NMR), as well as by comparison with authentic samples. GC-MS analysis of the fatty acid methyl esters and unsaponifiable matter revealed the presence of 46 fatty acids, 53 hydrocarbons, and 18 sterols. The different extracts were evaluated for their antihyperglycaemic activities. The MeOH, n-hexane, and EtOAc extracts exhibited a significant hypoglycaemic effect.

Two new acetylated flavonoid glycosides from Centaurium spicatum L.

Two new acetylated flavonol glycosides, quercetin 3-O-[(2,4-diacetyl-α-L-rhamnopyranosyl)-(1→6)]-2,4-diacetyl-ß-D-galactopyranoside (1) and quercetin 3-O-[(2,4-diacetyl-α-L-rhamnopyranosyl)-(1→6)]-3,4-diacetyl-ß-D-galactopyranoside (2), in addition to two known acetylated quercetin glycosides quercetin 3-O-[(2,3,4-triacetyl-α-L-rhamnopyranosyl)-(1→6)-ß-D-galactopyranoside (3) and quercetin 3-O-[(2,3,4-triacetyl-α-L-rhamnopyranosyl)-(1→6)-3-acetyl-ß-D-galactopyranoside (4), were isolated from the aerial part of Centaurium spicatum (L.) Fritsch (Gentianaceae). Structure elucidation, especially the localization of the acetyl groups, and complete (1)H and (13)C NMR assignments of these biologically active compounds were carried out using one- and two-dimensional NMR measurements, including (1)H- and (13)C-NMR, DEPT-135, H-H COSY, HMQC and HMBC, in addition to HR-FAB/MS experiments.

Rare trisubstituted sesquiterpenes daucanes from the wild Daucus carota.

Phytochemical and biological investigation of the roots of the wild Daucus carota ssp. carota afforded three new and four known compounds, including four sesquiterpenes daucane esters (1-3 [new], and 4), one polyacetylene (5), one sesquiterpene coumarin (6), and sitosterol glucoside. The structures of the new compounds were determined by comprehensive NMR studies, including DEPT, COSY, NOESY, HMQC and HMBC analyses. Based on an agar diffusion assay, 1, 2 and 4-6 were screened and found to contain a range of low antibacterial activities against four gram positive (Staphylococcus aureus, Streptomyces scabies, Bacillus subtilus, Bacillus cereus) and two gram negative species (Pseudomonas aeruginosa, Escherichia coli) as well as antifungal against Fusarium oxysporum and Aspergillus niger using cup agar diffusion assay.

Polyol monoterpenes and sesquiterpene lactones from the Pacific Northwest plant Artemisia suksdorfii.

Five new polyol monoterpenes (1-5) and seven new sesquiterpene lactones (6-12), along with five previously identified compounds, were isolated from the aerial parts of Artemisia suksdorfii. The structures of the new compounds were established by high-field NMR techniques (1H, 13C, 1H-1H DEPT, COSY, HMQC, and HMBC) and in case of 6 confirmed by X-ray analysis.

A new eudesmane derivative from Onopordon ambiguum.

Reinvestigation of Onopordon ambiguum extract afforded a new eudesmane derivative 1, in addition to the known elemanoid derivative 2. The structures of both compounds were determined by spectroscopic techniques, including 1H-, 13C-NMR, DEPT, 1H-1H and 1H-13C COSY analysis.