UPLC-ESI-MS/MS Profiling of Secondary Metabolites from Methanol Extracts of In Vivo and In Vitro Tissues of Daucus capillifolius Gilli (A Comparative Study).

Daucus capillifolius Gilli is a rare annual wild herb grown in Libya. It belongs to the Apiaceae family, which is one of the largest flowering plant families. Plants of this family are outstanding sources of various secondary metabolites with various biological activities. A UPLC-ESI-MS/MS analysis of different extracts of in vivo and in vitro tissues of Daucus capillifolius together with the fruit extract of the cultivated plant in both ionization modes was carried out for the first time in the current study. Our results reveal the tentative identification of eighty-seven compounds in the tested extracts, including thirty-two phenolic acids and their derivatives; thirty-seven flavonoid glycosides and aglycones of apigenin, luteolin, diosmetin, myricetin and quercetin, containing glucose, rhamnose, pentose and/or glucuronic acid molecules; seven anthocyanins; six tannins; three acetylenic compounds; and three nitrogenous compounds. The tentative identification of the above compounds was based on the comparison of their retention times and ESI-MS/MS fragmentation patterns with those previously reported in the literature. For this Apiaceae plant, our results confirm the presence of a wide array of secondary metabolites with reported biological activities. This study is among the first ones to shed light on the phytoconstituents of this rare plant.

Chemical and Biological Characterization of the Ethyl Acetate Fraction from the Red Sea Marine Sponge Hymedesmia sp.

Hymedesmiidae is one of the largest families of marine sponges and stands out as an exceptional source of variable metabolites with diverse biological activities. In this study, the ethyl acetate fraction (HE) of a Hymedesmia sp. marine sponge from the Red Sea, Egypt, was analyzed for the first time using Ultra-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) analysis. The analysis tentatively identified 29 compounds in this fraction, including the isolation and identification of six compounds (two pyrimidine nucleosides, one purine, and two pyrimidine bases in addition to one cerebroside) for the first time. The structures of the isolated compounds were established by 1D and 2D NMR (nuclear magnetic resonance), MS (mass spectrometry), and IR (infrared) spectroscopy. Furthermore, the cytotoxic, antioxidant, and antimicrobial activities of the ethyl acetate fraction were evaluated in vitro. The fraction exhibited strong DPPH scavenging activity with an IC50 of 78.7 µg/mL, compared to ascorbic acid as a positive control with an IC50 of 10.6 µg/mL. It also demonstrated significant cytotoxic activity with IC50 values of 13.5 µg/mL and 25.3 µg/mL against HCT-116 and HEP-2 cell lines, respectively, compared to vinblastine as a positive control with IC50 values of 2.34 µg/mL and 6.61 µg/mL against HCT-116 and HEP-2, respectively. Additionally, the ethyl acetate fraction displayed promising antibacterial activity against S. aureus with a MIC value of 62.5 µg/mL, compared to ciprofloxacin as a positive control with MIC values of 1.56 µg/mL for Gram-positive bacteria and 3.125 µg/mL for Gram-negative bacteria. It also exhibited activity against E. coli and P. aeruginosa with MIC values of 250 µg/mL and 500 µg/mL, respectively. Briefly, this is the first report on the biological activities and secondary metabolite content of the ethyl acetate fraction of Hymedesmia sp. marine sponge, emphasizing the potential for further research against resistant bacterial and fungal strains, as well as different cancer cell lines. The ethyl acetate fraction of Hymedesmia sp. is a promising source of safe and unique natural drugs with potential therapeutic and pharmaceutical benefits.

Iron oxide nanoparticles induced cytotoxicity, oxidative stress, cell cycle arrest, and DNA damage in human umbilical vein endothelial cells.

BACKGROUND: Nanotechnology and material science have developed enormously fast in recent years. Due to their excellent magnetic properties, iron oxide nanoparticles (IONPs) have been broadly applied in the field of bioengineering and biomedical. Thus, it is important to evaluate the safety issues and health effects of these nanomaterials. The present investigation was aimed to evaluate the adverse effects of IONPs on human umbilical vein endothelial cells (HUVECs). METHODS: The cytotoxic potential of IONPs was assessed by MTT and neutral red uptake (NRU) assays. The impact of IONPs on oxidative stress markers (glutathione (GSH) and lipid peroxidation (LPO)), reactive oxygen species (ROS) production, and mitochondrial membrane potential (MMP) was also examined. Furthermore, the toxic effect of IONPs was quantified by assessing DNA damage, cell cycle arrest, and apoptosis by quantitative real time PCR. RESULTS: We found that IONPs induce a dose-dependent cytotoxicity on HUVECs with IC50 value of 79.13 µg/mL. The results also displayed that IONPs induce oxidative stress, ROS production, and mitochondrial membrane dysfunction. The comet assay results exhibited IONPs induces DNA damage in HUVECs. We found significant cell cycle arrest at SubG1 phase in treated cells and consequent cell death was evidenced by microscopic analysis. Moreover, IONPs display substantial up-regulation of pro-apoptotic genes and down-regulation of anti-apoptotic gene evidenced by real time qPCR. CONCLUSION: Overall, our results clearly demonstrated that IONPs have the potential to induce cytotoxicity, DNA damage, cell cycle arrest, and apoptosis in HUVECs mediated through oxidative stress and ROS production. Thus, IONPs are cytotoxic and it should be handled with proper care.

Biomarker Quantification, Spectroscopic, and Molecular Docking Studies of the Active Compounds Isolated from the Edible Plant Sisymbrium irio L.

Phytochemical investigation of the ethanolic extract of the aerial parts of Sisymbrium irio L. led to the isolation of four unsaturated fatty acids (1-4), including a new one (4), and four indole alkaloids (5-8). The structures of the isolated compounds were characterized with the help of spectroscopic techniques such as 1D, 2D NMR, and mass spectroscopy, and by correlation with the known compounds. In terms of their notable structural diversity, a molecular docking approach with the AutoDock 4.2 program was used to analyze the interactions of the identified fatty acids with PPAR-γ and the indole alkaloids with 5-HT1A and 5-HT2A, subtypes of serotonin receptors, respectively. Compared to the antidiabetic drug rivoglitazone, compound 3 acted as a potential PPAR-γ agonist with a binding energy of -7.4 kcal mol-1. Moreover, compound 8 displayed the strongest affinity, with binding energies of -6.9 kcal/mol to 5HT1A and -8.1 kcal/mol to 5HT2A, using serotonin and the antipsychotic drug risperidone as positive controls, respectively. The results of docked conformations represent an interesting target for developing novel antidiabetic and antipsychotic drugs and warrant further evaluation of these ligands in vitro and in vivo. On the other hand, an HPTLC method was developed to quantify α-linolenic acid in the hexane fraction of the ethanol extract of S. irio. The regression equation/correlation coefficient (r2) for linolenic acid was Y = 6.49X + 2310.8/0.9971 in the linearity range of 100-1200 ng/band. The content of α-linolenic acid in S. irio aerial parts was found to be 28.67 µg/mg of dried extract.

Chemical constituents from Centaurothamnus maximus and their antimicrobial activity.

A new sesquiterpene lactone, 3ß,10α-dihydroxy-10ß-(hydroxymethyl)-8α-(4-hydroxymethacrylate)-1αH,5αH,6ßH,7αH-guai-4(15), 11(13)-dien-6,12-olide (1), along with twenty-one known compounds, were identified from the aerial parts of Centaurothamnus maximus. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Compounds (2, 3, 5‒13 and 15‒22) were identified from C. maximus for the first time. Antibacterial and antifungal activities of the isolated compounds were tested using the agar disc diffusion method. Compounds that demonstrated promising antimicrobial activity were evaluated for their minimum inhibitory concentration (MIC). The results showed that compounds 3 and 7 were the most effective antibacterial compounds against B. subtilis ATCC 6633, S. aureus ATCC 25923 and S. pyogenes ATCC 27736, with MIC estimates between 8 and 32 mg/mL. In addition, compound 2 exhibited the strongest antifungal activity against C. albicans ATCC 14243 and C. krusei ATCC 14243 with MIC 8 mg/mL.

Twenty-two compounds were first isolated from Centaurothamnus maximusThe structure of the new sesquiterpene lactone, thamnolide (1), was established.Antibacterial and antifungal activities were tested for the isolated compounds.Compounds 3 and 7 were the strongest antibacterial compounds whilst 2 exhibited the strongest antifungal activity.

Copper Oxide Nanoparticles Exhibit Cell Death Through Oxidative Stress Responses in Human Airway Epithelial Cells: a Mechanistic Study.

Copper oxide nanoparticles (CuONPs) are purposefully used to inhibit the growth of bacteria, algae, and fungi. Several studies on the beneficial and harmful effects of CuONPs have been conducted in vivo and in vitro, but there are a few studies that explain the toxicity of CuONPs in human airway epithelial cells (HEp-2). As a result, the purpose of this study is to look into the dose-dependent toxicity of CuONPs in HEp-2 cells. After 24 h of exposure to 1-40 µg/ml CuONPs, the MTT and neutral red assays were used to test for cytotoxicity. To determine the mechanism(s) of cytotoxicity in HEp-2 cells, additional oxidative stress assays (LPO and GSH), the amount of ROS produced, the loss of MMP, caspase enzyme activities, and apoptosis-related genes were performed using qRT-PCR. CuONPs exhibited dose-dependent cytotoxicity in HEp-2 cells, with an IC50 value of ~ 10 µg/ml. The morphology of HEp-2 cells was also altered in a dose-dependent manner. The involvement of oxidative stress in CuONP-induced cytotoxicity was demonstrated by increased LPO levels and ROS generation, as well as decreased levels of GSH and MMP. Furthermore, activated caspase enzymes and altered apoptotic genes support CuONPs' ability to induce apoptosis in HEp-2 cells. Overall, this study demonstrated that CuONPs can cause apoptosis in HEp-2 cells via oxidative stress; therefore, CuONPs may pose a risk to human health and should be handled and used with caution.

Insecticidal Activity and Free Radical Scavenging Properties of Isolated Phytoconstituents from the Saudi Plant Nuxia oppositifolia (Hochst.).

Chromatographic purification of the alcoholic extract from the aerial parts of the Saudi plant Nuxia oppositifolia (Hochst.), Benth., resulted in five isolated phenolic compounds. Two flavones, hispidulin (1) and jaceosidin (2), and the phenylethanoid glycosides, verbascoside (3), isoverbascoside (4), and conandroside (5), were identified and their chemical structures were determined by spectroscopic analyses. The insecticidal activity of compounds 1 and 2, in addition to 11 compounds isolated in a previous research (6-16), was evaluated against the Yellow Fever mosquito, Aedes aegypti. Four compounds displayed adulticidal activity with LD50 values of 2-2.3 µg/mosquito. Free radical scavenging properties of the plant extracts and compounds (1-5) were evaluated by measuring the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate radical cation (ABTS•+) scavenging activity. All compounds exhibited notable activity, compared with the positive control, l-Ascorbic acid. This study suggests that N. oppositifolia could be a promising source of secondary metabolites, some with lethal adulticidal effect against Ae. aegypti.

Oxidative Stress Mediated Cytotoxicity, Cell Cycle Arrest, and Apoptosis Induced by Rosa damascena in Human Cervical Cancer HeLa Cells.

Rosa damascena Mill (Damask rose), belonging to the Rosaceae family, is known for medicinal purposes in traditional medicine system. However, its anticancer activity has not been studied yet in detail. Herein, we aimed to investigate the cytotoxic effects of R. damascena hexane (RA-HE) and methanolic (RA-ME) extracts against human breast (MCF-7), lung epithelial (A-549), and cervical (HeLa) cancer cells. The RA-HE and RA-ME showed more potent cytotoxic effects against HeLa cells with an IC50 of 819.6 and 198.4 µg/ml, respectively. Further, cytotoxic concentrations of most effective extract (RA-ME) were used to evaluate the mechanism of cytotoxicity involved in HeLa cells. A concentration-dependent induction of lipid peroxidation (LPO) and reduction of glutathione (GSH) in HeLa cells treated with 250-1000 µg/ml of RA-ME confirms the association of oxidative stress. We also detected a noteworthy increase in reactive oxygen species (ROS) production and a decline in mitochondrial membrane potential (MMP) level in RA-ME-exposed HeLa cells. Flow cytometric data showed a strong dose-response relationship in cell cycle analysis between subG1 phase in HeLa cells and RA-ME treatment. Similarly, a concentration-dependent increase was recorded with Annexin V assay in HeLa cells going to late apoptosis. In conclusion, our findings suggest that RA-ME-induced cytotoxicity and apoptosis in HeLa cells are mediated by oxidative stress.

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).

Protective effects of Nigella sativa extract against H2 O2 -induced cell death through the inhibition of DNA damage and cell cycle arrest in human umbilical vein endothelial cells (HUVECs).

Oxidative stress is known to induce cytotoxicity and apoptosis in endothelial cells and indorse development of atherosclerosis. The aim of this research was to assess the cytoprotective effects of ethanolic extract of Nigella sativa (NSE) against H2 O2 -induced cell death in human umbilical vein endothelial cells (HUVECs) and also study the probable mechanisms through which NSE exhibited cyto-protection. The cytotoxicity was measured by exposing the HUVECs with NSE (10-200 µg/ml) and H2 O2 (25-1000 µM) for 24 h. Then, the HUVECs were pretreated with noncytotoxic doses (10-50 µg/ml) of NSE for 24 h before administration of 200 µM H2 O2 for 24 h. The MTT, NRU, and morphological assays were performed to assess the cytotoxicity and cyto-protection. Potential antioxidant activity of NSE on oxidative stress marker (glutathione [GSH] and lipid peroxidation [LPO]) was also evaluated. The fluorescence probe, DCF-DA, and Rh123 were applied to measure the reactive oxygen species (ROS) level and mitochondrial membrane potential. Moreover, flow cytometric analysis and comet assay were used to study the cell cycle arrest and DNA damage, respectively. The concentrations (10, 30, and 50 µg/ml) of NSE were found to protect HUVECs against H2 O2 (200 µM)-induced cytotoxicity in HUVECs. Pretreatment of HUVECs with NSE significantly reduced the LPO and ROS levels and restored the GSH and loss of MMP induced by H2 O2 . Furthermore, NSE inhibited H2 O2 -induced cell cycle arrest and cellular DNA damage in HUVECs. Altogether, these results suggest that NSE can prevent H2 O2 -induced cell death, and NSE could be a potential candidate that can prevent HUVECs against toxicants.

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.

Siphonocholin isolated from red sea sponge Siphonochalina siphonella attenuates quorum sensing controlled virulence and biofilm formation.

Increasing incidence of multi-drug resistant bacterial pathogens, especially in clinical settings, has been developed into a grave health situation. The drug resistance problem demands the necessity for alternative unique therapeutic policies. One such tactic is targeting the quorum sensing (QS) controlled virulence and biofilm production. In this study, we evaluated a marine steroid Siphonocholin (Syph-1) isolated from Siphonochalina siphonella against Chromobacterium violaceum (CV) 12472, Pseudomonas aeruginosa (PAO1), Methicillin-resistant Staphylococcus aureus (MRSA) and Acinetobacter baumannii (BAA) for biofilm and pellicle formation inhibition, and anti-QS property. MIC of Syph-1 against MRSA, CV, PAO1 was found as 64 µg/mL and 256 µg/mL against BAA. At selected sub-MICs, Syph-1 significantly (P ≤ 0.05) decreased the production of QS regulated virulence functions of CV12472 (violacein) and PAO1 [elastase, total protease, pyocyanin, chitinase, exopolysaccharides, and swarming motility]. The Syph-1 significantly decreased (p = 0.005) biofilm formation ability of tested bacterial pathogens, at sub-MIC level (PAO1 > MRSA > CV > BAA) and pellicle formation in A. baumannii (at 128 µg/mL). Molecular docking and simulation results indicated that Siph-1 was bound at the active site of BfmR N-terminal domain with high affinity. This study highlights the anti-QS and anti-biofilm activity of Syph-1 against bacterial pathogens reflecting its broad spectrum anti-infective potential.

Petroselinum sativum protects HepG2 cells from cytotoxicity and oxidative stress induced by hydrogen peroxide.

A number of liver diseases are known to be caused by oxidative stress. Petroselinum sativum (P. sativum; parsley) is popular for its anti-inflammatory, antimicrobial, anticancer, antioxidant and antidiabetic activities. However, till date the hepatoprotective potential of chloroform extract of P. sativum (PSA) on hydrogen peroxide (H2O2) induced cytotoxicity and oxidative stress in human liver (HepG2) cells have not been studied. Therefore, this study was framed to evaluate whether the levels of hydrogen peroxide (H2O2) induced cytotoxicity and oxidative stress in HepG2 cells could be diminished by pretreating the cells with PSA. MTT assay, NRU assay, morphological alterations, glutathione (GSH) depletion, lipid peroxidation (LPO), ROS generation and loss of mitochondrial membrane potential (MMP) were assessed by using non-cytotoxic concentrations (5, 10 and 25 µg/mL) of PSA against H2O2 (0.25 mM) induced damage in HepG2 cells. The results demonstrated that pretreatment of HepG2 cells with PSA offered protective properties by lowering the LPO and ROS generation and elevating the cell viability, GSH and MMP levels. Together, these results suggest that PSA has the hepatoprotective effect on H2O2 induced cell death in HepG2 cells.

Corn Silk (Zea mays L.) Induced Apoptosis in Human Breast Cancer (MCF-7) Cells via the ROS-Mediated Mitochondrial Pathway.

Cancer has been recognized as one of the life-threating diseases. Breast cancer is a leading cause of mortality among women. In spite of current developments in the therapy and diagnosis of cancer, the survival rate is still less. Recently, plant-derived natural products gain attention as anticancer agents due to the nontoxic nature. Therefore, the aim of present study was to investigate the anticancer capacity of corn silk extract (CSE) on human breast cancer (MCF-7) and normal human mesenchymal (hMSC-TERT4) cells. Following 24 h treatment to corn silk extract, the cytotoxicity was assessed by MTT, NRU, and morphological assays. The oxidative stress markers (GSH and LPO), ROS production, MMP change, and expression of apoptotic marker genes (p53, Bax, Bcl-2, caspase-3, and caspase-9) were also studied in MCF-7 cells treated at 250 to 1000 µg/ml of CSE for 24 h. Our results showed that CSE decreased the cell viability and increased the apoptosis in a dose-dependent manner. The level of LPO and ROS production was found significantly higher; however, GSH and MMP level was observed lower in CSE-treated MCF-7 cells. The real-time PCR data showed a significant upregulation in p53, Bax, caspase-3, and caspase-9 and downregulation in the mRNA expression of Bcl-2 genes in MCF-7 cells exposed to CSE. Collectively, the data from this study stated that corn silk extract induced apoptosis via the ROS-mediated mitochondrial pathway in MCF-7 cells.

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.

Anticancer Potential of Green Synthesized Silver Nanoparticles Using Extract of Nepeta deflersiana against Human Cervical Cancer Cells (HeLA).

In this study, silver nanoparticles (AgNPs) were synthesized using aqueous extract of Nepeta deflersiana plant. The prepared AgNPs (ND-AgNPs) were examined by ultraviolet-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), and energy dispersive spectroscopy (EDX). The results obtained from various characterizations revealed that average size of synthesized AgNPs was 33 nm and in face-centered-cubic structure. The anticancer potential of ND-AgNPs was investigated against human cervical cancer cells (HeLa). The cytotoxic response was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), neutral red uptake (NRU) assays, and morphological changes. Further, the influence of cytotoxic concentrations of ND-AgNPs on oxidative stress markers, reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), cell cycle arrest and apoptosis/necrosis was studied. The cytotoxic response observed was in a concentration-dependent manner. Furthermore, the results also showed a significant increase in ROS and lipid peroxidation (LPO), along with a decrease in MMP and glutathione (GSH) levels. The cell cycle analysis and apoptosis/necrosis assay data exhibited ND-AgNPs-induced SubG1 arrest and apoptotic/necrotic cell death. The biosynthesized AgNPs-induced cell death in HeLA cells suggested the anticancer potential of ND-AgNPs. Therefore, they may be used to treat the cervical cancer cells.

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.

New acyclic secondary metabolites from the biologically active fraction of Albizia lebbeck flowers.

The total extract of Albizia lebbeck flowers was examined in vivo for its possible hepatoprotective activity in comparison with the standard drug silymarin at two doses. The higher dose expressed promising activity especially in reducing the levels of AST, ALT and bilirubin. Fractionation via liquid-liquid partition and reexamination of the fractions revealed that the n-butanol fraction was the best in improving liver biochemical parameters followed by the n-hexane fraction. However, serum lipid parameters were best improved with CHCl3 fraction. The promising biological activity results initiated an intensive chromatographic purification of A. lebbeck flowers fractions. Two compounds were identified from natural source for the first time, the acyclic farnesyl sesquiterpene glycoside1-O-[6-O-α-l-arabinopyranosyl-ß-d-glucopyranoside]-(2E,6E-)-farnesol (6) and the squalene derivative 2,3-dihydroxy-2,3-dihydrosqualene (9), in addition to eight compounds reported here for the first time from the genus Albizia; two benzyl glycosides, benzyl 1-O-ß-d-glucopyranoside (1) and benzyl 6-O-α-l-arabinopyranosyl ß-d-glucopyranoside (2); three acyclic monoterpene glycosides, linalyl ß-d-glucopyranoside (3) and linalyl 6-O-α-l-arabinopyranosyl-ß-d-glucopyranoside (4); (2E)-3,7-dimethylocta-2,6-dienoate-6-O-α-l arabinopyranosyl-ß-d-glucopyranoside (5), two oligoglycosides, n-hexyl-α-l arabinopyranosyl-(1 â†’ 6)-ß-d-glucopyranoside (creoside) (7) and n-octyl α-l-arabinopyranosyl-(1 â†’ 6)-ß-d-glucopyranoside (rhodiooctanoside) (8); and ethyl fructofuranoside (10). The structures of the isolated compounds were elucidated based on extensive examination of their spectroscopic 1D and 2D-NMR, MS, UV, and IR data. It is worth mentioning that, some of the isolated linalol glycoside derivatives were reported as aroma precursors.