Chemical composition and potential antioxidant, anti-inflammatory, and analgesic efficacy of Cistus albidus L.

This study aims to assess the chemical composition of the aqueous extract of Cistus albidus L. leaves, as well as the potential of aqueous and hydroethanol extracts of the leaves and seeds as analgesic, anti--inflammatory, and antioxidant agents. The contents of phenolics and inorganic constituents were determined in C. albidus seeds and leaves; antioxidant capacity was assessed by 3 complementary and diverse tests. The carrageenan-induced paw edema technique was used to investigate the anti-inflammatory effect in vivo, and albumin denaturation to evaluate the anti-inflammatory effect in vitro. The acetic acid-induced contortion test, the tail-flick test, and the plantar test were used to assess the analgesic effi cacy in vivo. Chemical analysis was performed by UPLC-MS/MS to quantify several phenolic compounds including catechin (1,627.6 mg kg-1), quercitrin (1,235.8 mg kg-1) and gallic acid (628. 2 mg kg-1). The ICP analysis revealed that potassium and calcium were the main inorganic components in the seeds and leaves of C. albidus. The hydroethanolic extract of the leaves showed the highest content of polyphenols/flavonoids, whereas the highest value of proantho cyanidins was detected in the aqueous extract of the seeds. All extracts showed potent antioxidant activity related to different phenolic compounds (quercetin, gallic acid, astragalin, catechin, and rutin). The aqueous extract of the leaves strongly inhibited paw edema (76.1 %) after 6 h of treatment and showed maximal inhibition of protein denaturation (191.0 µg mL-1 for 50 % inhibition) and analgesic activity in different nociceptive models. The presented data reveal that C. albidus extracts potentially show antioxidant, anti-inflammatory, and analgesic activities that could confirm the traditional use of this plant.

Antioxidant, Antimicrobial, and Insecticidal Properties of Chemically Characterized Essential Oils Extracted from Mentha longifolia: In Vitro and In Silico Analysis.

The present study aimed to explore the phytochemical profile, and evaluate the antioxidant, antimicrobial, and insecticidal properties, of Moroccan Mentha longifolia L. essential oil (ML-EO) using in vitro and in silico assays. Noteworthily, as chromatography (GC-MS/MS) revealed that ML-EO is majorly composed of piperitenone oxide (53.43%), caryophyllene (20.02%), and (-) germacrene D (16.53%). It possesses excellent antioxidant activity with an IC50 of 1.49 ± 0.00 for DPPH and 0.051 ± 0.06 µg/mL for ABTS. Moreover, the RP and TAC activities were 0.80 ± 0.01 µg/mL and 315.532 ± 0.00 mg EAA/g, respectively. ML-EO exhibited a potent antimicrobial effect, specifically against Pseudomonas aeruginosa. It also exhibited strong antifungal ability, especially against Candida albicans. Regarding insecticidal activity, for ML-EO, a dose of 20 µL/mL produced a complete reduction in fecundity, fertility, and emergence of adult C. maculatus with mortality rates reaching 100%. In silico results showed that the antioxidant activity is mostly attributed to α-Cadinol, the antibacterial efficiency is attributed to piperitenone oxide, and antifungal capacity is related to cis-Muurola-4(15),5-diene and piperitenone oxide. Accordingly, ML-EO has high potential to be used as an alternative for preserving food and stored grain and protecting them against microbes and insect pests in the food and pharmaceutical sectors.

Study of the Phytochemical Composition, Antioxidant Properties, and In Vitro Anti-Diabetic Efficacy of Gracilaria bursa-pastoris Extracts.

In this study, a comparison was made of the chemical makeup of different extracts obtained from Gracilaria bursa-pastoris, a type of red seaweed that was gathered from the Nador lagoon situated in the northern part of Morocco. Additionally, their anti-diabetic and antioxidant properties were investigated. The application of GC-MS technology to analyze the fatty acid content of the samples revealed that linoleic acid and eicosenoic acid were the most abundant unsaturated fatty acids across all samples, with palmitic acid and oleic acid following in frequency. The HPLC analysis indicated that ascorbic and kojic acids were the most prevalent phenolic compounds, while apigenin was the most common flavonoid molecule. The aqueous extract exhibited significant levels of polyphenols and flavonoids, registering values of 381.31 ± 0.33 mg GAE/g and 201.80 ± 0.21 mg QE/g, respectively. Furthermore, this particular extract demonstrated a remarkable ability to scavenge DPPH radicals, as evidenced by its IC50 value of 0.17 ± 0.67 mg/mL. In addition, the methanolic extract was found to possess antioxidant properties, as evidenced by its ability to prevent ß-carotene discoloration, with an IC50 ranging from 0.062 ± 0.02 mg/mL to 0.070 ± 0.06 mg/mL. In vitro study showed that all extracts significantly inhibited the enzymatic activity of α-amylase and α-glucosidase. Finally, molecular docking models were applied to assess the interaction between the primary phytochemicals identified in G. bursa-pastoris extracts and the human pancreatic α-amylase and α-glucosidase enzymes. The findings suggest that these extracts contain bioactive substances capable of reducing enzyme activity more effectively than the commercially available drug acarbose.

Quercetin and Ferulic Acid Elicit Estrogenic Activities In Vivo and In Silico.

In this study, we examined the sub-acute toxicity of quercetin and ferulic acid and evaluated their effects on protein, cholesterol, and estrogen levels in vivo. Six groups of female Wistar rats were fed by gavage. The first and second groups represent the positive (Clomiphene citrate 10 mg/kg) and negative (NaCl 0.9%) control groups, while the other groups received quercetin and ferulic acid at doses of 5 and 10 mg/kg/day for 28 days. The sub-acute toxicity was monitored by examining the weights, biochemical parameters (AST, ALT, ALP, urea, and CREA), and histological changes in the kidneys and liver of the treated animals. Furthermore, the in vivo estrogenic effects were studied in terms of the serum and ovarian cholesterol levels, serum estradiol, and uterine proteins. Finally, Docking studies were conducted to evaluate the binding affinity of quercetin and ferulic acid for alpha and beta estrogen receptors. Results showed that both compounds were devoid of any signs of nephrotoxicity or hepatotoxicity. Additionally, quercetin and ferulic acid caused significant estrogenic effects evidenced by an increase of 8.7 to 22.48% in serum estradiol, though to a lesser amount than in the reference drug-treated group (64.21%). Moreover, the two compounds decreased the serum cholesterol levels (12.26-32.75%) as well as the ovarian cholesterol level (11.9% to 41.50%) compared to the negative control. The molecular docking in estrogen alpha and estrogen beta active sites showed high affinity of quercetin (-10.444 kcal/mol for estrogen alpha and -10.662 kcal/mol for estrogen beta) and ferulic acid (-6.377 kcal/mol for estrogen alpha and -6.3 kcal/mol for estrogen beta) to these receptors. This study provides promising insights into the potential use of quercetin as a therapeutic agent for the management of female fertility issues.

Extracts of Brocchia cinerea (Delile) Vis Exhibit In Vivo Wound Healing, Anti-Inflammatory and Analgesic Activities, and Other In Vitro Therapeutic Effects.

The plant Brocchia cinerea (Delile) (B. cinerea) has many uses in traditional pharmacology. Aqueous (BCAE) and ethanolic extracts (BCEE) obtained from the aerial parts can be used as an alternative to some synthetic drugs. In vitro, DPPH, FRAP and TAC are three tests used to measure antioxidant efficacy. Antibacterial activities were determined against one Gram positive and two Gram negative strains of bacteria. The analgesic power was evaluated in vivo using the abdominal contortion model in mice, while carrageenan-induced edema in rats was the model chosen for the anti-inflammatory test; wound healing was evaluated in an experimental second degree burn model. The results of the phytochemical analysis showed that BCEE had the greatest content of polyphenols (21.06 mg AGE/g extract), flavonoids (10.43 mg QE/g extract) and tannins (24.05 mg TAE/g extract). HPLC-DAD reveals the high content of gallic acid, quercetin and caffeic acid in extracts. BCEE has a strong antiradical potency against DPPH (IC50 = 0.14 mg/mL) and a medium iron reducing activity (EC50 = 0.24 mg/mL), while BCAE inhibited the growth of the antibiotic resistant bacterium, P. aeruginosa (MIC = 10 mg/mL). BCAE also exhibited significant pharmacological effects and analgesic efficacy (55.81% inhibition 55.64% for the standard used) and the re-epithelialization of wounds, with 96.91% against 98.60% for the standard. These results confirm the validity of the traditional applications of this plant and its potential as a model to develop analogous drugs.

In Vitro and In Silico Studies of Antimicrobial, and Antioxidant Activities of Chemically Characterized Essential Oil of Artemisia flahaultii L. (Asteraceae).

The present study investigated the antioxidant and antimicrobial activities as well as characterized the chemical composition of the essential oils (EO) isolated from Artemisia flahaultii (EOF). EOF was extracted using hydro-distillation, and the chemical composition of EOF was ascertained by gas chromatography coupled with mass spectrometry (GC/MS). To assess antioxidant capacity, three tests were used: the 2,2-diphenyl-1-picrylhydrazil (DPPH), the total antioxidant capacity (TAC) and the ferric-reducing antioxidant power (FRAP) test. The antimicrobial activity of EOF was investigated using the diffusion assay and minimal inhibitory concentration assays (MICs). By use of in silico structure-activity simulations, the inhibitory potency against nicotinamide adenine dinucleotide phosphate (NADPH), physicochemical characters, pharmaco-centric properties and absorption, distribution, metabolism, excretion (ADME) characteristics of EOF were determined. GC/MS analysis reveals 25 components majorly composed of D-Limonene (22.09%) followed by ß-pinene (15.22%), O-cymene (11.72%), ß-vinylnaphthalene (10.47%) and benzene 2,4-pentadiynyl (9.04%). The capacity of DPPH scavenging by EOF scored an IC50 of 16.00 ± 0.20 µg/mL. TAC revealed that the examined oils contained considerable amounts of antioxidants, which were determined to be 1094.190 ± 31.515 mg ascorbic acid equivalents (AAE)/g EO. Results of the FRAP method showed that EOF exhibited activity with EC50 = 6.20 ± 0.60 µg/mL. Values for minimal inhibitory concentration (MIC) against certain clinically important pathogenic bacteria demonstrate EOF's potent antibacterial activity. MIC values of 1.34, 1.79, and 4.47 µg/mL against E. coli, B. subtilis and S. aureus were observed respectively. EOF exhibited significant antifungal activities against two stains of fungi: F. oxysporum and C. albicans, with values of 10.70 and 2.23 µg/mL, respectively. Of the total, 25 essential oils were identified. 2,4-Di-tert-butylphenol and capillin were the most active molecules against NADPH. The ADME prediction revealed that EOF was characterized by useful physicochemical characteristics and pharmaco-centric properties. The findings of this study show that the EOF can be used as an alternative to treat microbial resistance. Based on the in silico studies, EOF can be used as an "eco-friendly" NADPH inhibitor.

Antibacterial, Antioxidant, and in silico NADPH Oxidase Inhibition Studies of Essential Oils of Lavandula dentata against Foodborne Pathogens.

Food is always subjected to microbial infection and lipid peroxidation, which frequently leads to serious food intoxications. In the present study, essential oils (EOs) extracted from Lavandula dentata Moroccan species and its major component (linalool) were chemically characterized and their antioxidant potential and antibacterial properties against foodborne pathogenic bacteria were examined. EOs phytochemical profile was carried out using gas chromatography-mass spectrometry analysis (GC-MS). The antioxidant potential was evaluated, in vitro, by use of the ß-carotene discoloration assay and in silico vs. NADPH oxidase enzymatic complex as an antioxidant marker. The antibacterial proprieties were assessed by use of minimal inhibitory concentration (MIC) and disc diffusion methods, against Gram (-) bacteria (Pseudomonas aeruginosa, Salmonella enterica, and Escherichia coli) and Gram (+) bacteria (Bacillus subtilis and Staphylococcus aureus). Linalool (49.71%) was the major component among the eighteen components identified in Lavandula dentate EO, followed by camphor (14.36%) and borneol (8.21%). The studied EO and linalool compounds showed important antioxidant activity through the ß-carotene discoloration test with IC50 values of 35.72 ± 1.21 mg/mL and 30.32 ± 1.23 mg/mL, respectively. Among all the analyzed compounds of lavender EOs, thymol, carvacrol, and α-terpineol were the most active compounds against NADPH oxidase with a glide score of -6.483, -6.17, and -4.728 kcal/mol, respectively. 2D and 3D views showed the formation of hydrogen bonds between the most active compounds and the active site of NADPH oxidase. The antibacterial data showed a significant activity of Lavandula dentata essences against tested foodborne pathogenic bacteria, especially against S. aureus and B. subtilis. Linalool proved active toward the same bacteria and had closer activity to that of lavender essential oil. In light of the obtained findings, the essential oil of Lavandula dentata Moroccan species can be used in the packaging sector as a promising natural food conservative to limit lipid oxidation and treat foodborne infections.

Phenolic Composition, Wound Healing, Antinociceptive, and Anticancer Effects of Caralluma europaea Extracts.

Caralluma europaea (Guss.) is an important medicinal plant widely used in Morocco for various traditional purposes. Our work aimed to evaluate the phenolic composition, wound healing, antinociceptive, and anticancer activities of C. europaea extracts. Moreover, this study assessed the beneficial effect of C. europaea phytocompounds on the TRADD, cyclooxegenase-2, Wnt/ß-catenin, and tyrosine kinase signaling pathways. The wound healing effect of C. europaea formulations against skin burn was evaluated for 21 days. The cytotoxic effect of the C. europaea extracts was evaluated against human leukemic (K562 and HL60) and liver cancer cell lines (Huh-7) using the MTT test. All the phytoconstituents identified by UHPLC in the polyphenols were docked for their inhibitory power on protein casein kinase-1, glycogen synthase kinase-3-ß, cyclooxegenase-2, tyrosine kinase, and TRADD. Luteolin and kaempferol are the main compounds identified in C. europaea polyphenols. The group treated with polyphenols showed the greatest wound contractions and all tested extracts presented a significant antinociceptive effect. Polyphenols showed a remarkable antitumoral activity against the K562, HL60 and Huh-7 cell lines. Saponins exerted an important cytotoxic effect against the Huh-7 cell line, whereas no cytotoxicity was observed for the hydroethanolic and flavonoids extracts. Hesperetin and trimethoxyflavone presented the highest docking G-score on tyrosine kinase and cyclooxygenase, respectively.

Evaluation of the toxicity of Caralluma europaea (C.E) extracts and their effects on apoptosis and chemoresistance in pancreatic cancer cells.

Pancreatic adenocarcinoma is a disease with no effective treatment. Chemo-resistance contributes to the dismal prognosis for patients diagnosed with the disease. This study aims to evaluate the toxicity and the effect of Caralluma europaea (C.E) extracts on cancer cell survival, apoptosis, chemo-resistance, and pro-cancer pathways, in pancreatic cancer. The acute and subacute toxicities of C.E extracts were evaluated. The cytotoxic effect on pancreatic cancer cell survival and apoptosis was determined by MTT assay and DNA fragmentation. The expression of cancer stemness markers was measured using Western blot. A molecular docking was used to test the possible effects of C.E compounds in inhibiting the Hedgehog and activating caspase-3. The hydroethanolic extract's DL50 was over 5000 mg/kg. During the subacute toxicity, only saponins extract showed some hepatic toxicity signs. Cells treated with C.E extracts combined with gemcitabine revealed an additive anti-survival activity. C.E extracts sensitized resistant MIA-PaCa-2 to gemcitabine treatment. Most of the C.E extracts downregulated the expression of cancer stemness-associated genes. Luteolin-7-O-glucoside presented the highest docking Gscore on human Smoothened. Isorhamnetin-3-O-rutinoside induced apoptosis via activation of caspase-3. C.E extracts can be considered safe in inhibiting pancreatic cancer cell survival, inducing apoptosis, and sensitizing cells to chemotherapy via Hedgehog inhibition and caspase-3 activation.Communicated by Ramaswamy H. Sarma.

Origanum majorana L. polyphenols: in vivo antiepileptic effect, in silico evaluation of their bioavailability, and interaction with the NMDA receptor.

Introduction: Epilepsy is a chronic brain disease characterized by repeated seizures and caused by excessive glutamate receptor activation. Many plants are traditionally used in the treatment of this disease. This study aimed to evaluate the bioavailability of a polyphenolic extract obtained from Origanum majorana L. (OMP) leaves, as well as its antiepileptic activity and its potential mechanism of action. Methods: We have developed and validated a simple, rapid, and accurate stability-indicating reversed-phase liquid chromatographic method for the simultaneous determination of caffeine and quercetin in rat plasma. The OMP antiepileptic effect was evaluated with pilocarpine-induced seizures, and a docking method was used to determine the possible interaction between caffeic acid and quercetin with the N-methyl-D-aspartate (NMDA) receptor. Results and Discussion: Both compounds tested showed low bioavailability in unchanged form. However, the tested extract showed an anticonvulsant effect due to the considerably delayed onset of seizures in the pilocarpine model at a dose of 100 mg/kg. The molecular docking proved a high-affinity interaction between the caffeic acid and quercetin with the NMDA receptor. Taken together, OLP polyphenols demonstrated good antiepileptic activity, probably due to the interaction of quercetin, caffeic acid, or their metabolites with the NMDA receptor.

Solanum elaeagnifolium Var. Obtusifolium (Dunal) Dunal: Antioxidant, Antibacterial, and Antifungal Activities of Polyphenol-Rich Extracts Chemically Characterized by Use of In Vitro and In Silico Approaches.

The present work was designed to study the chemical composition and the antioxidant and antimicrobial properties of fruits (SFr) and leaf (SF) extracts from Solanum elaeagnifolium var. obtusifolium (Dunal) Dunal (S. elaeagnifolium). The chemical composition was determined using HPLC-DAD analysis. Colorimetric methods were used to determine polyphenols and flavonoids. Antioxidant capacity was assessed with DPPH, TAC, and FRAP assays. Antimicrobial activity was assessed using disk diffusion and microdilution assays against two Gram (+) bacteria (Staphylococcus aureus ATCC-6633 and Bacillus subtilis DSM-6333) and two Gram (-) bacteria (Escherichia coli K-12 and Proteus mirabilis ATCC-29906), while the antifungal effect was tested vs. Candida albicans ATCC-1023. By use of in silico studies, the antioxidant and antimicrobial properties of the studied extracts were also investigated. HPLC analysis showed that both fruits and leaf extracts from S. elaeagnifolium were rich in luteolin, quercetin, gallic acid, and naringenin. Both SFr and SF generated good antioxidant activity, with IC50 values of 35.15 ± 6.09 µg/mL and 132.46 ± 11.73 µg/mL, respectively. The EC50 of SFr and SF was 35.15 ± 6.09 µg/mL and 132.46 ± 11.73 µg/mL, respectively. SFr and SF also showed a good total antioxidant capacity of 939.66 ± 5.01 µg AAE/and 890.1 ± 7.76 µg AAE/g, respectively. SFr had important antibacterial activity vs. all tested strains-most notably B. subtilis DSM-6333 and E. coli, with MICs values of 2.5 ± 0.00 mg/mL and 2.50 ± 0.00 mg/mL, respectively. SFr demonstrated potent antifungal activity against C. albicans, with an inhibition diameter of 9.00 ± 0.50 mm and an MIC of 0.31 ± 0.00 mg/mL. The in silico approach showed that all compounds detected in SFr and SF had high activity (between -5.368 and 8.416 kcal/mol) against the receptors studied, including NADPH oxidase, human acetylcholinesterase, and beta-ketoacyl-[acyl carrier protein] synthase.

The LC-MS/MS Identification and Analgesic and Wound Healing Activities of Lavandula officinalis Chaix: In Vivo and In Silico Approaches.

We earlier emphasized in vivo the lavender plant's (Lavandula officinalis Chaix.) anti-inflammatory and estrogenic activities and described the chemical compositions of its hydro-ethanolic (HE) extract. We used LC-MS/MS and GC-MS analyses to profile the phytochemical composition of the HE extract and to assess the analgesic and wound-healing effects of both the hydro-ethanolic (HE) and polyphenolic (LOP) extracts in vivo and in silico. The analgesic activity was studied using two methods: acetic acid and formalin injections in mice. The wound-healing activity was carried out over 25 days using a burn model in rats. In the in silico study, the polyphenols identified in the plant were docked in the active sites of three enzymes: casein kinase-1, cyclooxygenase-2, and glycogen synthase kinase-3ß. The LC-MS/MS identified some phenolic compounds, mainly apigenin, catechin, and myricetin, and the GC-MS analysis revealed the presence of 19 volatile compounds with triazole, D-glucose, hydroxyphenyl, and D-Ribofuranose as the major compounds. The HE and LOP extracts showed significant decreases in abdominal writhes, and the higher licking time of the paw (57.67%) was observed using the LOP extract at 200 mg/kg. Moreover, both extracts showed high healing percentages, i.e., 99.31 and 92.88%, compared to the control groups, respectively. The molecular docking showed that myricetin, amentoflavone, apigenin, and catechin are the most active molecules against the three enzyme receptors. This study sheds light on the potential of L. officinalis Chaix as a source of natural products for pharmaceutical applications for analgesic purposes as well as their utility in promoting burn-healing activity.

GC-MS Profiling, In Vitro Antioxidant, Antimicrobial, and In Silico NADPH Oxidase Inhibition Studies of Essential Oil of Juniperus thurifera Bark.

Juniperus thurifera is a native species to the mountains of the western Mediterranean region. It is used in traditional medicine as a natural treatment against infections. The present study aimed to carry out the chemical analysis and evaluate the antioxidant, antimicrobial, as well as in silico inhibition studies of the essential oils from Juniperus thurifera bark (EOEJT). Chemical characterization of EOEJT was done by gas chromatography (GC-MS). We have performed three antioxidant assays (Reducing power (FRAP), 2, 2-diphenylpicrylhydrazyl (DPPH), and total antioxidant capacity (TAC)) of the EOEJT. We next evaluated the antimicrobial activity against in silico study, which was carried out to help evaluate the inhibitory effect of EOEJT against NADPH oxidase. Results of the GC/MS analysis revealed seven major compounds in EOEJT wherein muurolol (36%) and elemol (26%) were the major components. Moreover, EOEJT possessed interesting antioxidant potential with an IC50 respectively of 21.25 ± 1.02 µg/mL, 481.02 ± 5.25 µg/mL, and 271 µg EAA/mg in DPPH, FRAP, and total antioxidant capacity systems. Molecular docking of EOEJT in NADPH oxidase active site showed inhibitory activity of α-cadinol and muurolol with a glide score of -6.041 and -5.956 Kcal/mol, respectively. As regards the antibacterial and antifungal capacities, EOEJT was active against all tested bacteria and all fungi, notably, against Escherichia coli K12 with an inhibition diameter of 21 mm and a MIC value of 0.67 mg/mL, as well as against Proteus mirabilis ATCC 29906 with an inhibition diameter of 18.33 ± 1.15 mm and a MIC value of 1.34 mg/mL. A more pronounced effect was recorded for the fungal pathogens Fusarium oxysporum MTCC 9913 with inhibition of 37.44 ± 0.28% and MIC value of 6.45 mg/mL, as well as against Candida albicans ATCC 10231 with an inhibition diameter of 20.33 ± 1.15 mm and a MIC value of 0.67 ± 0.00 mg/mL. Altogether, these results highlight the importance of EOEJT as a source of natural antibacterial and antioxidant drugs to fight clinically important pathogenic strains.

Apoptosis-mediated anti-proliferative activity of Calligonum comosum against human breast cancer cells, and molecular docking of its major polyphenolics to Caspase-3.

Due to poor diagnosis breast cancer in women has emerged as the most common cause of death disease in developing countries. Medicinal plants have been used for thousands of years and can be useful in healthcare, especially in developing countries. Ethanol extracts of leaves of fire bush or arta (Calligonum comosum; EECC), exhibited significant anticancer potencies against two breast cancer cell lines, MCF-7 and MDA 231. These in vitro effects of EECC indicated potential anticancer activities that were determined to be specific since minimal toxicity was recorded against MCF-12, a non-cancerous breast cell line used as a reference. EECC also induced cell cycle arrest in MCF-7 and MDA 231 as revealed by the increased proportions of sub-G1 cells. Fluorescence-activated cell sorter analysis (FACS), utilizing double staining by annexin V-FITC/propidium iodide, revealed that the observed cytotoxic effects were mediated via apoptosis and necrosis. FACS measurement of thegreater in fluorescence intensity, linked with oxidation of DCFH to DCF, revealed that apoptosis was attributable to production of free radicals. EECC-mediated apoptosis was further validated by observation of up-regulation in the "executioner" enzyme, caspase 3. The current findings reveal that EECC exhibits significant, selective cytotoxicity to breast cancer cells, that proceeds via the generation of ROS, which culminates in apoptosis. The anti-proliferative effects of EECC weres further verified by use of a structure-based, virtual screening between its major bioactive polyphenolic constituents and the apoptosis executioner marker enzyme, caspase-3. Based on their glide score values against the active site of caspase 3, some phyto-constituents present in EECC, such as DL-alpha-tocopherol and campesterol, exhibited distinctive, drug-like potential with no predicted toxicity to non-target cells. Taken together, the usefulness of natural phenolic and flavonoid compounds contained in Calligonum comosum were suggested to be potent anticancer agents.

Antioxidant, Anti-Proliferative Activity and Chemical Fingerprinting of Centaurea calcitrapa against Breast Cancer Cells and Molecular Docking of Caspase-3.

Centaurea calcitrapa has been intensively utilized in ethnomedicinal practices as a natural therapeutic recipe to cure various ailments. The current study aimed to chemically characterize ethanolic extract of C. calcitrapa (EECC) aerial parts (leaves and shoots) by use of gas chromatography-mass spectrometry analyses (GC-MS) and investigate its antioxidant and in vitro anticancer activities, elucidating the underlying molecular mechanism by use of flow cytometry-based fluorescence-activated cell sorting (FACS) and conducting in silico assessment of binding inhibitory activities of EECC major compounds docked to caspase-3. CG-MS profiling of EECC identified a total of 26 major flavonoids and polyphenolic compounds. DPPH and ABTS assays revealed that EECC exhibits potent antioxidant activity comparable to standard reducing agents. Results of the proliferation assay revealed that EECC exhibit potent, dose-dependent cytotoxic activities against triple-positive (MCF-7) and triple-negative (MDA-MB-231) breast cancer cell models, with IC50 values of 1.3 × 102 and 8.7 × 101 µg/mL, respectively. The observed cytotoxic effect was specific to studied cancer cells since EECC exhibited minimal (~<10%) cytotoxicity against MCF-12, a normal breast cell line. FACS analysis employing annexin V-FITC/propidium iodide double labeling demonstrated that the observed anti-proliferative activity against MCF-7 and MDA-MB-231 was mediated via apoptotic as well as necrotic signaling transduction processes. The increase in fluorescence intensity associated with DCFH oxidation to DCF, as reported by FACS, indicated that apoptosis is caused by generation of ROS. The use of caspase-3-specific fluorogenic substrate revealed a dose-dependent elevation in caspase-3 substrate-cleavage activity, which further supports EECC-mediated apoptosis in MCF-7 cells. The major EECC compounds were examined for their inhibitory activity against caspase-3 receptor (1HD2) using molecular docking. Three compounds exhibited the highest glide score energy of −5.156, −4.691 and −4.551 kcal/mol, respectively. Phenol, 2,6-dimethoxy established strong binding in caspase-3 receptor of hydrogenic type, with residue ARG 207 and of PI-PI stacking type with residue HIS 121. By contract, hexadecenoic acid showed 3 H-bond with the following residues: ASN 615, ASN 616a and THR 646. Taken together, the current findings reveal that EECC exhibits significant and specific cytotoxicity against breast cancer cells mediated by the generation of ROS and culminating into necrosis and apoptosis. Further investigations of the phytoconstituents-rich C. calcitrapa are therefore warranted against breast as well as other human cancer cell models.