Evaluation of Cytotoxicity of the Methanolic Extract of Red Sea Marine Sponge Xestospongia Testudinaria and Its Related Compounds Against MCF-7 Human Breast Cancer Cells.

Background: Breast cancer is a leading cause of death and one of the most common fatal medical conditions in the world. Chemical compounds of various types have been identified in the Red Sea marine sponge Xestospongia testudinaria, including sterol esters, sterols, indole alkaloids, and brominated polyunsaturated fatty acids. These compounds have demonstrated promising biological features, which in cludes anti-inflammatory, cancer preventive, and antioxidant capacities. Methods: The cytotoxic potential of Xestospongia testudinaria was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and morphological alterations in MCF-7 cell line. Furthermore, the flow cytometry was also utilized to assess apoptosis and identify changes in the cell cycle; besides, cell migration was assessed by scratch wound-healing assay. Results: A significant dose-dependent decrease in the percentage of MCF-7 cell viability was observed with IC50 39.8 ug/mL. Functional studies were performed on MCF-7 to show that Xestospongia testudinaria raises apoptotic cell death and induces growth arrest at the G1/G0 while inhibiting cell migration in scratch assay. Conclusion: These results demonstrated that Xestospongia testudinaria extract has an inhibitory effect on breast cancer cells proliferation, migration and induce apoptosis. Thus, it holds great promise as a potential treatment for breast cancer.

Virtual screening and molecular dynamics simulation study of abyssomicins as potential inhibitors of COVID-19 virus main protease and spike protein.

The lack of any effective cure for the infectious COVID-19 disease has created a sense of urgency and motivated the search for effective antiviral drugs. Abyssomicins are actinomyces-derived spirotetronates polyketides antibiotics known for their promising antibacterial, antitumor, and antiviral activities. In this study, computational approaches were used to investigate the binding mechanism and the inhibitory ability of 38 abyssomicins against the main protease (Mpro) and the spike protein receptor-binding domain (RBD) of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The results identified abyssomicins C, J, W, atrop-O-benzyl abyssomicin C, and atrop-O-benzyl desmethyl abyssomicin C as the most potential inhibitors of Mpro and RBD with binding energy ranges between -8.1 and -9.9 kcal mol-1; and between -6.9 and -8.2 kcal mol-1, respectively. Further analyses of physicochemical properties and drug-likeness suggested that all selected active abyssomicins, with the exception of abyssomicin J, obeyed Lipinski's rule of five. The stability of protein-ligand complexes was confirmed by performing molecular dynamics simulation for 100 ns and evaluating parameters such as such as root mean square deviation (RMSD), root mean square fluctuation (RMSF), radius of gyration (Rg), solvent accessible surface area (SASA), total number of contacts, and secondary structure. Prime/MM-GBSA (Molecular Mechanics-General Born Surface Area) and principal component analysis (PCA) analyses also confirmed the stable nature of protein-ligand complexes. Overall, the results showed that the studied abyssomicins have significant interactions with the selected protein targets; therefore, they were deemed viable candidates for further in vitro and in vivo evaluation.Communicated by Ramaswamy H. Sarma.

Salvadora persica L.: Toothbrush tree with health benefits and industrial applications - An updated evidence-based review.

Salvadora persica L. is also known as Arak (in Arabic) and Peelu (in Urdu). Its frequent use as a toothbrush (miswak) is highly recommended by Prophet Muhammad. With a long history in folk medicine for centuries, S. persica was used in oral hygiene, food, cosmetics, fuel, and even as a medicine. Previous phytochemical investigation of its different parts afforded different classes of secondary metabolites such as flavonoids, glycosides, sterols, terpenes, carbohydrates and alkaloids. Organic sulfur-containing compounds and elemental sulfur are also present. In addition, there is a huge research on its biological potentials and industrial applications. Many pharmacological activities were reported experimentally, including antimicrobial, antioxidant, analgesic, anthelmintic, anti-inflammatory, antiulcer, sedative, anticonvulsant, anti-osteoporosis, antidiabetic, hypo-lipidemic, in addition to wound-healing, antidepressant and antitumor activities. Recently, a possible activity against COVID-19 protease was documented by molecular docking. This review tries to provide a recent detailed documentation of folk and modern uses of S. persica, focusing on the possible relations between its chemical constituents, pharmacological properties, and industrial applications. Moreover, a brief about recent analytical and validation methods for the major antimicrobial component is reported.

Sterols and Triterpenes from Dobera glabra Growing in Saudi Arabia and Their Cytotoxic Activity.

A new lupane caffeoyl ester, lup-20(29)-ene 3ß-caffeate-30-al (7), and a new oleanane-type triterpene, 3ß-hydroxyolean-13(18)-en-12-one (17), were isolated from the aerial parts of Dobera glabra (Forssk), along with ten known triterpenes, including seven lupane-type lupeol (1), 30-nor-lup-3ß-ol-20-one (2), ∆1-lupenone (3), lup-20(29)-en-3ß,30-diol (4), lupeol caffeate (5), 30-hydroxy lup-20(29)-ene 3ß-caffeate (6), and betunaldehyde (8); three oleanane-type compounds were also identified, comprising δ-amyrone (15), δ-amyrin (16), and 11-oxo-ß-amyrin (18); together with six sterols, comprising ß-sitosterol (9), stigmasterol (10), 7α-hydroxy-ß-sitosterol (11), 7α-hydroxy-stigmasterol (12), 7-keto-ß-sitosterol (13), and 7-keto-stigmasterol (14). Their structures were elucidated using a variety of spectroscopic techniques, including 1D (1H, 13C, and DEPT-135 13C) and 2D (1H-1H COSY, 1H-13C HSQC, and 1H-13C HMBC) nuclear magnetic resonance (NMR) and accurate mass spectroscopy. Subsequently, the different plant extracts and some of the isolated compounds (1-9, 11 and 13) were investigated for their possible cytotoxic activity in comparison to cisplatin against a wide array of aggressive cancer cell lines, such as colorectal cancer (HCT-116), hepatocellular carcinoma (HepG-2), and prostate cancer (PC-3) cell lines. Compound 11 displayed broad cytotoxicity against all of the tested cell lines (IC50 ≅ 8 µg/mL in all cases), and a high safety margin against normal Vero cells (IC50 = 70 µg/mL), suggesting that 11 may be a highly selective and effective anticancer agent candidate. Notably, the evidence indicated that the mode of action of compound 11 could possibly consist of the inhibition of phosphodiesterase I (80.2% enzyme inhibition observed at 2 µM compound concentration).

Vacillantins A and B, New Anthrone C-glycosides, and a New Dihydroisocoumarin Glucoside from Aloe vacillans and Its Antioxidant Activities.

A new dihydroisocoumarin glucoside, vacillanoside (3), and two new anthrone C-glycosides microdantin derivatives; vacillantin A (10) and B (11), together with nine known compounds belonging to the anthraquinone, anthrone and isocoumarin groups were isolated from the leaves of Aloe vacillans. The structures were determined based on spectroscopic evidence including 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HRESIMS) data, along with comparisons to reported data. The leaves were used to extract compounds with different solvents. The extracts were tested for antioxidant activity with a variety of in vitro tests including 2,2-diphenyl-1-picrylhydrazyl (DPPH•), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate (ABTS•+), ferric reducing antioxidant power assay (FRAP), superoxide, and nitric oxide radical scavenging assays. The dichloromethane fraction was most active, displaying significant free radical scavenging activity. The n-butanol fraction also showed notable activity in all assays. Therefore, these findings support the potential use of A. vacillans leaves as an antioxidant medication due to the presence of polyphenolic compounds.

Comparative evaluation of cytotoxic, antimicrobial and antioxidant activities of the crude extracts of three Plectranthus species grown in Saudi Arabia.

Natural products from medicinal plants represent major resource of novel therapeutic substances for combating serious diseases including cancers and microbial infections. The genus Plectranthus (Family: Labiatae) represents a large and widespread group of species with a diversity of traditional uses in treatment of various ailments. Therefore, this research study aimed to evaluate the cytotoxic, antimicrobial and antioxidant activities of three Plectranthus species growing in Saudi Arabia namely P. cylindraceus Hocst. ex Benth., P. asirensis JRI Wood and P. barbatus Andrews. Moreover, this work focused on the isolation of the active constituents responsible for the activities from the most active Plectranthus species. The extracts were tested for their cytotoxic activity against three cancer cell lines (Hela, HepG2 and HT-29), using MTT-test, antimicrobial activity against Gram positive, Gram negative bacterial and fungal strains using broth micro-dilution assay for minimum inhibitory and bactericidal concentrations (MIC and MBC) and antioxidant activity using scavenging activity of DPPH radical and ß-carotene-linoleic acid methods. The ethanolic extracts of the Plectranthus species showed remarkable cytotoxic activity against all cancer cell lines with IC50 values ranging between 10.1 ±â€¯0.33 to 102.6 ±â€¯8.66 µg/mL and a great and antimicrobial activity with MIC values between 62.5 and 250 µg/mL. In addition, the three Plectranthus species showed almost moderate antioxidant activity. The most interesting cytotoxic and antimicrobial results were observed with the extract of P. barbatus. Consequently, this extract was partitioned between water and n-hexane, chloroform and n-butanol and tested. The cytotoxic activity resided predominantly in the n-hexane and chloroform fractions. The analysis of the chloroform fraction led to the isolation of four diterpenoid compounds, two of labdane- and two of abietane-type, which were identified as coleonol B, forskolin, sugiol and 5,6-dehydrosugiol. Purification of the n-hexane fraction led to isolation of a major abietane-type diterpene, which was identified as ferruginol. Sugiol, 5,6-dehydrosugiol and ferruginol were isolated for the first time from P. barbatus in this study. The isolated diterpenoids showed variable cytotoxic effects with IC50 values between 15.1 ±â€¯2.03 and 242 ±â€¯13.3 µg/mL, a great antimicrobial activity with MIC values between 15.6 and 129 µg/mL and a total antioxidant activity ranging from 23.1 ±â€¯2.9 to 69.2 ±â€¯3.8%.

Evaluation of cytotoxicity, cell cycle arrest and apoptosis induced by Anethum graveolens L. essential oil in human hepatocellular carcinoma cell line.

Anethum graveolens L. (A. graveolens) commonly known as dill, is an essential oil bearing plant extensively being used in traditional system of medicine. However, the reports on the components and biological responses of A. graveolens essential oil (AG-EO) from Saudi Arabia are scarce. The present study was designed to explore the presence of basic constituents and apoptosis induced by AG-EO in HepG2 cells. The constituents in AG-EO was analyzed by Gas chromatography-Mass spectroscopy (GC-MS). Cytotoxicity of AG-EO was measured by MTT assay and cell cycle arrest and apoptosis assays were conducted by using flow cytometer. Based on GC-MS analysis, the main constituents present in AG-EO were carvone (53.130%), dillapole (25.420%), dihydrocarvone 2 (11.350%) and dihydrocarvone 1 (6.260%). A few other minor components were also identified viz. cis-dihydrocarveol (0.690%), limonene (0.580%), isodihydrocarveol (0.370%), myristicin (0.210%) and cis-arsone (0.190%). The cytotoxicity results showed that AG-EO decrease the cell viability and inhibit the cell growth of HepG2 cells in a concentration-dependent manner. The inhibitory activity of AG-EO was found with IC50 = 59.6 ±â€¯5.64. The cell cycle arrest results showed that HepG2 cells exposed to AG-EO exhibited an increase in G2/M and pre-G1 cell population after 24 h exposure. Furthermore, the flow cytometry data revealed the primarily activation of cell death by apoptosis manners in HepG2 cells exposed to AG-EO. Overall, results from this study highlighted the anticancer potential of AG-EO, which could be considered as a new agent for the management of hepatocellular carcinoma.

Isolation, biological evaluation and validated HPTLC-quantification of the marker constituent of the edible Saudi plant Sisymbrium irio L.

Phytochemical investigation and chromatographic purification of the n-hexane fraction of the aerial parts of the edible Saudi plant Sisymbrium irio led to the isolation of ß-sitosterol (1), stigmasterol (2) and ß-sitosterol-ß-d-glucoside (3). The cytotoxic effects of the n-hexane, dichloromethane, ethyl acetate and n-butanol fractions were tested against three cancer cell lines viz., MCF-7, HCT-116 and HepG2, using the crystal violet staining (CVS) method, while the antibacterial activity against a number of pathogenic bacterial strains, was also estimated using the broth microdilution assay. The n-hexane fraction showed potent cytotoxic activities against all tested human cancer cell lines (IC50: 11.7-13.4 µg/mL), while the dichloromethane fraction was particularly potent against HCT-116 cells (IC50: 5.42 µg/mL). On the other hand, the n-hexane and EtOAc fractions demonstrated significant inhibitory activities against the Gram positive bacteria S. pyogenes and C. perfringens; and the Gram negative bacterium S. enteritidis. Our results warrant the therapeutic potential of S. irio as nutritional supplement to reduce the risk of contemporary diseases. Additionally, a validated high performance thin-layer chromatography (HPTLC) method was developed for the quantitative analysis of biomarker ß-sitosterol glucoside (isolated in high quantity) from the n-hexane fraction. The system was found to furnish a compact, sharp, symmetrical and high resolution band for ß-sitosterol glucoside (Rf  = 0.43 ± 0.002). The limit of detection (LOD) and limit of quantification (LOQ) for ß-sitosterol glucoside was found to be 21.84 and 66.18 ng band-1, respectively. ß-sitosterol glucoside was found to be present only in n-hexane fraction (2.10 µg/mg of dried fraction) while it was absent in the other fractions of S. irio which validated the high cytotoxic and antibacterial activity of n-hexane fraction of S. irio.

Prenylated flavonoids from Commiphora opobalsamum stem bark.

A phytochemical study on the stem bark of Commiphora opobalsamum looking for cytotoxic compounds afforded eleven flavonoids, including six previously undescribed prenylated congeners, comophorin A-E, and comophoroside A. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Isolated compounds were biologically evaluated using in vitro cytotoxicity MTT-based assay against two cancer cell lines; namely human hepato-cellular carcinoma (HepG-2) and human breast adenocarcinoma (MCF-7). Comophoroside A revealed to retain the strongest cytotoxic activity against MCF-7 and HepG-2 cell lines with IC50 values of 8 and 12 µg/mL, respectively.

New Cytotoxic Seco-Type Triterpene and Labdane-Type Diterpenes from Nuxia oppositifolia.

Chromatographic purification of the n-hexane and dichloromethane extracts of Nuxia oppositifolia aerial parts, growing in Saudi Arabia, resulted in the isolation and characterization of three new labdane-type diterpene acids, 2ß-acetoxy-labda-7-en-15-oic acid (1), 2ß-acetoxy-7-oxolabda-8-en-15-oic acid (2), 2ß-acetoxy-6-oxolabda-7-en-15-oic acid (3), and one new seco-triterpene, 3,4-seco olean-12-en-3,30 dioic acid (4), together with 10 known lupane, oleanane and ursane-type triterpenes, as well as the common phytosterols, ß-sitosterol and stigmasterol (5-16). Their structures have been assigned on the basis of different spectroscopic techniques including 1D and 2D NMR. Moreover, 13 of the isolated compounds were tested on the human cancer cell lines HeLa (cervical), A549 (lung) and MDA (breast), and most of the compounds showed potent cytotoxic activities in vitro.

Cytotoxic Compounds from the Saudi Red Sea Sponge Xestospongia testudinaria.

Bioassay-guided fractionation of the organic extract of the Red Sea sponge Xestospongia testudinaria led to the isolation of 13 compounds including two new sterol esters, xestosterol palmitate (2) and xestosterol ester of l6'-bromo-(7'E,11'E,l5'E)-hexadeca-7',11',l5'-triene-5',13'-diynoic acid (4), together with eleven known compounds: xestosterol (1), xestosterol ester of 18'-bromooctadeca-7'E,9'E-diene-7',15'-diynoic acid (3), and the brominated acetylenic fatty acid derivatives, (5E,11E,15E,19E)-20-bromoeicosa-5,11,15,19-tetraene-9,17-diynoic acid (5), 18,18-dibromo-(9E)-octadeca-9,17-diene-5,7-diynoic acid (6), 18-bromooctadeca-(9E,17E)-diene-7,15-diynoic acid (7), 18-bromooctadeca-(9E,13E,17E)-triene-7,15-diynoic acid (8), l6-bromo (7E,11E,l5E)hexadeca-7,11,l5-triene-5,13-diynoic acid (9), 2-methylmaleimide-5-oxime (10), maleimide-5-oxime (11), tetillapyrone (12), and nortetillapyrone (13). The chemical structures of the isolated compounds were accomplished using one- and two-dimensional NMR, infrared and high-resolution electron impact mass spectroscopy (1D, 2D NMR, IR and HREIMS), and by comparison with the data of the known compounds. The total alcoholic and n-hexane extracts showed remarkable cytotoxic activity against human cervical cancer (HeLa), human hepatocellular carcinoma (HepG-2), and human medulloblastoma (Daoy) cancer cell lines. Interestingly, the dibrominated C18-acetylenic fatty acid (6) exhibited the most potent growth inhibitory activity against these cancer cell lines followed by Compounds 7 and 9. Apparently, the dibromination of the terminal olefinic moiety has an enhanced effect on the cytotoxic activity.

Chemical composition and biological evaluation of essential oils of Pulicaria jaubertii.

BACKGROUND: The present study reports and compares the results of Gas Chromatographic-Mass analyses of Pulicaria jaubertii leaf (P-1) and root (P-2) essential oils, as well as their in vitro antimicrobial and cytotoxic activities. MATERIALS AND METHODS: The chemical composition of P-1 and P-2 essential oils of P. jaubertii, was investigated by GC-MS. Moreover, the essential oils were evaluated for their antimicrobial activity using the broth micro-dilution assay for minimum inhibitory concentrations (MIC). The crystal violet staining method (CVS) was used for evaluation of their cytotoxic activity on HEPG-2 and MCF-7 human cell lines. RESULTS: This investigation led to the identification of 16 constituents in P-1, and 23 constituents in P-2, representing 99.92% and 94.74% of the oils respectively. Oxygenated monoterpenes were found to be the major group in both P-1 (99.47%) and P-2 (89.88%). P-1 consists almost entirely of p-Menth-6-en-2-one (Carvotanacetone, 98.59%). P-2 is characterized by high contents of each of Dimethoxydurene (38.48%), Durenol (26.89%) and 2',4'-Dimethoxy-3'-methylacetophenone (20.52%). Both oils showed moderate antimicrobial activity against the Gram-positive strains and C. albicans. However, no activity was shown against Gram-negative bacteria. P-1 showed a significant cytotoxic activity against both MCF-7 and HEPG-2 (IC50 = 3.8 and 5.1 µg/ml, respectively), while P-2 showed selective cytotoxic activity against MCF-7 cell line (IC50 = 9.3 µg/ml). CONCLUSION: The potent cytotoxic and moderate antimicrobial activities of P-1 may be attributed to its high content of Carvotanacetone.

Revision of the absolute configuration at C(23) of lanostanoids and isolation of secondary metabolites from formosan soft coral Nephthea erecta.

Three new oxygenated ergostanoids, 1-3, one known ergostanoid, 4, one new trinoreudesmadienone, 5, one new calamenene type sesquiterpene, 6, and one known aristolane-type sesquiterpene, (-)-aristolone (7), have been isolated from the AcOEt extract of the soft coral Nephthea erecta. The structures of these compounds were determined by extensive spectroscopic and X-ray crystallographic analysis, as well as Mosher's method. We revised the absolute configuration at C(23) in the side chain of some lanostanoids as a result of the Mosher's products of 1 (i.e., 1a and 1b). The cytotoxicities against selected cancer cells and the anti-inflammatory effects of these tested metabolites 1-7 were determined in vitro.

Cytotoxic lupane-, secolupane-, and oleanane-type triterpenes from Viburnum awabuki.

Bioassay-guided fractionation of the methanolic extract of Viburnum awabuki afforded two new lupane triterpene derivatives; 6 beta-hydroxyl-3,20-dioxo-30 norlupane-28-oic acid (1) and 3,4-secolup-4,20-dihydroxy-3,28-dioic acid-3-oic acid methyl ester (2), along with seven known lupane and oleanane-type triterpenes (3-9). The structure of the isolated compounds was assigned using different spectroscopic techniques including 1D and 2D NMR. The 13CNMR data of compounds 5 and 9 is reported for the first time. Triterpenes 1, 2, and 7-9 showed in vitro cytotoxic activity against several tumor cell lines.

Cytotoxic xenia diterpenoids from the soft coral Xenia umbellata.

Eleven new xenia diterpenoids, umbellacins A-G (1-7), 14,15-epoxy-xeniolide H (8), 3-acetyl-14,15-epoxy-xeniolide H (9), and umbellacins H and I (10, 11), were isolated from a methylene chloride-soluble fraction of the soft coral Xenia umbellata. The structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Sesquiterpenoids and norsesquiterpenoids from the Formosan soft coral Lemnalia laevis.

Eight new nornardosinane sequiterpenoids, laevinols A-H (1-8), a new neolemnane sesquiterpenoid, laevinone A (9), and the previously known 6beta-acetyl-4beta,5beta-dimethyl-1(10)alpha-epoxy-2beta-hydroxy-7-oxodecalin (10) and 11,12-dihydroxy-6,10-eremophiladiene (11) were isolated from the methylene chloride solubles of the Formosan soft coral Lemnalia laevis. Their structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Xenia diterpenoids from the formosan soft coral Xenia blumi.

Eight new xenia diterpenoids, blumiolide-A (1) (novel carbon skeleton), blumiolide-B (2), 9-deoxy-isoxeniolide-A (3), 9-deoxy-7,8-epoxy-isoxeniolide-A (4), 9-deacetoxy-7,8-epoxy-13-epi-xenicin (5), 9-deoxy-7,8-epoxy-xeniolide-A (6), blumiolide-C (7), and blumicin-A (8), were isolated from the methylene chloride solubles of the Formosan soft coral Xenia blumi. Their structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Sulfur-containing polybromoindoles from the Formosan red alga Laurencia brongniartii.

Five new sulfur-containing polybromoindoles, 2-methylsulfinyl-3-methylthio-4,5,6-tribromoindole (1), 3-methylsulfinyl-2,4,6-tribromoindole (2), 4,6-dibromo-2,3-di(methylsulfinyl)indole (3), 3,3'-bis(2'-methylsulfinyl-2-methylthio-4,6,4',6'-tetrabromo)indole (4), and 3,3-bis(4,6-dibromo-2-methylsulfinyl)indole (5), as well as seven known sulfur-containing polybromoindoles, 3-methylthio-2,4,6-tribromoindole (6), 3-methylthio-2,4,5,6-tetrabromoindole (7), 4,6-dibromo-2,3-di(methylthio)indole (8), 2,3-di(methylthio)-4,5,6-tribromoindole (9), 4,6-dibromo-2-methylsulfinyl-3-(methylthio)indole (10), 4,6-dibromo-2-(methylthio)indole (11), and 3,3-bis(4,6-dibromo-2-methylthio)indole (12), have been isolated from the Formosan red alga Laurencia brongniartii. The structures were elucidated by extensive spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Xenibellols A and B, new diterpenoids from the formosan soft coral Xenia umbellata.

Xenibellols A (1) and B (2), possessing an unprecedented diterpenoid skeleton, were isolated from the soft coral Xenia umbellata. The structures of xenibellols A and B were established by extensive analysis of spectroscopic data.

Prenylbicyclogermacrane diterpenoids from the formosan soft coral Nephthea pacifica.

Ten new prenylbicyclogermacrane diterpenoids, pacificins A-J (1-10), were isolated from the methylene chloride solubles of the Formosan soft coral Nephthea pacifica. The structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.