Cymbopogon proximus phytochemicals induce S-phase arrest in A549 lung cancer cell lines via CDK2/cyclin A2 inhibition: gas chromatography-mass spectrometry and molecular docking analyses.

Cymbopogon proximus comprises several phytoconstituent classes that are reported to possess anticancer activity; however, studies on the anticancer potentials of the plant are lacking. C. proximus was extracted using solvents with increasing polarity. In-vitro cytotoxic activity of C. proximus extracts was examined against liver (HepG2), lung (A549), prostate (PC3), and bone (MG63) cell lines using MTT assay in comparison to doxorubicin. Flow cytometry was used to analyze the cell cycle for identification of the phase of inhibition. Chemical composition of the most active fraction was examined using the GC/MS technique. Molecular docking was used to explore the mechanism of cytotoxicity against A549, and the results were confirmed by Western blot analysis. Petroleum ether fraction was the highly effective fraction against A549 with IC50 = 14.02 ± 2.79. GC/MS analysis of Pet.Eth led to the identification of nine compounds in unsaponifiable matter and 27 components in the saponifiable fraction. Di-N-octyl phthalate, 3-ß-hydroxylean-11.13(18)-dien-30-oic acid methyl ester, elemol hydrocarbons, linoelaidic acid and linoleic acid demonstrated the lowest docking binding scores and similar binding modes against CDK2 as compared to that attained by the native ligand R-Roscovitine "CDK2 ATP inhibitor". Western blot analysis demonstrated that CDK2/cyclinA2 protein expression has been suppressed in A549 cell lines by Pet.Eth fraction.

Correction to "Coccoloba uvifera leaves: Polyphenolic profile, Cytotoxicity, and Antioxidant Evaluation".

[This corrects the article DOI: 10.1021/acsomega.3c04025.].

Correction: New cyclic glycolipids from Silene succulenta promote in vitro MCF-7 breast carcinoma cell apoptosis by cell cycle arrest and in silico mitotic Mps1/TTK inhibition.

[This corrects the article DOI: 10.1039/D3RA01793A.].

Coccoloba uvifera Leaves: Polyphenolic Profile, Cytotoxicity, and Antioxidant Evaluation.

This study aimed to investigate the chemical composition of Coccoloba uvifera leaves and evaluate the antioxidant and antitumor effects of the total extract and its major metabolites. Four assays were used to determine the antioxidant activity, including radical scavenging abilities of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), radical cation, and ferric-reducing power. Additionally, vincristine was used as a reference medication to examine the anticancer activity on Ehrlich aesthete carcinoma cells (EACC). Nine compounds were isolated from C. uvifera leaves aqueous methanol extract. Their structures were identified as gallic acid (1), methyl gallate (2), protocatechuic acid methyl ester (3), protocatechuic acid (4), quercetin 3-O-ß-d-glucopyranoside (isoquercitrin, 5), kaempferol 3-O-ß-D-neohespridoside (6), myricitrin 4″-O-gallate (7), myricetin 3-O-ß-d-glucopyranoside (8), and myricetin 3-O-arabinopyranoside (9). The majority possess noticeable antioxidant and antitumor properties. However, compounds 1, 5, 4, 2, and 7 displayed a strong antioxidant potential in terms of DPPH radical scavenging activity, with values of 85.72 ± 0.30, 82.16 ± 0.20, 81.34 ± 0.20, 79.62 ± 0.29, and 79.34 ± 0.20%, respectively. Compounds 4, 1, 5, 7, and 2 revealed high reducing power activity, with respective values of 1.348 ± 0.043, 1.303 ± 0.011, 1.154 ± 0.020, 1.058 ± 0.032, and 1.056 ± 0.019. Compounds 4 and 1 showed the highest ABTS radical scavenging capabilities (91.90 ± 0.24 and 91.83 ± 0.74%) and ferric-reducing power ability (1979 ± 14.53 and 1965 ± 26.86 µmol Trolox/100 g, respectively). Compound 4 has the highest level of cytotoxicity, resulting in 78.710.21% dead cells.

Anti-SARS-CoV-2 in vitro potential of castor oil plant (Ricinus communis) leaf extract: in-silico virtual evidence.

Ricinus communis L. is a medicinal plant that displays valuable pharmacological properties, including antioxidant, antimicrobial, analgesic, antibacterial, antiviral and anti-inflammatory properties. This study targeted to isolate and identify some constituents of R. communis leaves using ultra-performance liquid chromatography coupled with mass spectroscopy (UPLC-MS/MS) and different chromatographic techniques. In vitro anti-MERS and anti-SARS-CoV-2 activity for different fractions and for two pure isolated compounds, lupeol (RS) and ricinine (RS1) were evaluated using a plaque reduction assay with three different mechanisms and IC50 based on their cytotoxic concentration (CC50) from an MTT assay using Vero E6 cell line. Isolated phytoconstituents and remdesivir are assessed for in-silico anti-COVID-19 activity using molecular docking tools. The methylene chloride extract showed pronounced virucidal activity against SARS-CoV-2 (IC50 = 1.76 µg/ml). It was also shown that ricinine had superior potential activity against SARS-CoV-2, (IC50 = 2.5 µg/ml). Lupeol displayed the most potency against MERS, (IC50 = 5.28 µg/ml). Ricinine appeared to be the most biologically active compound. The study showed that R. communis and its isolated compounds have potential natural virucidal activity against SARS-COV-2; however, additional exploration is necessary and study for their in vivo activity.

New cyclic glycolipids from Silene succulenta promote in vitro MCF-7 breast carcinoma cell apoptosis by cell cycle arrest and in silico mitotic Mps1/TTK inhibition.

In vitro anticancer screening of Silene succulenta Forssk. aerial parts (Caryophyllaceae) showed that the n-hexane fraction was a highly effective fraction against breast carcinoma cell lines (MCF-7) with IC50 = 15.5 µg mL-1. The bioactive-guided approach led to the isolation of two new cyclic glucolipids from the n-hexane fraction, identified as a 1,2'-cyclic ester of 11-oxy-(6'-O-acetyl-ß-d-glucopyranosyl) behenic acid (1) as a C-11 epimeric mixture and 11(R)-oxy-(ß-d-glucopyranosyl)-1,2'-cyclic ester of behenic acid (2). An in vitro cytotoxicity study showed the potential suppression of MCF-7 cells with IC50 values of 11.7 ± 0.04 and 6.6 ± 0.01 µg mL-1 for compounds 1 and 2, respectively, compared to doxorubicin (IC50 = 3.83 ± 0.01 µg mL-1). Accordingly, only cell cycle tracking for the most active compound (2) was assessed. The cell cycle investigation showed that compound 2 altered the cell cycle at G0/G1, S, and G2/M phases in MCF-7 treated cells. In addition, its powerful apoptotic ability resulted in a significant increase in the early and late stages of apoptosis. Moreover, molecular docking analysis, which was performed against the anticancer mitotic (or spindle assembly) checkpoint target Mps1 kinase, showed that the two new cyclic glycolipids (1 and 2) possess high binding affinity of -7.7 and - 7.6 kcal mol-1, respectively, compared to its ATP ligand. Overall, this report emphasizes that natural cyclic glycolipids can be used as potential antitumour breast cancer agents.

Antiviral activity of castor oil plant (Ricinus communis) leaf extracts.

ETHNOPHARMACOLOGICAL RELEVANCE: Ricinus communis L., commonly known as castor oil plant, is a precious traditional medicine with a history of thousands of years in the world. Castor oil plant has high traditional and medicinal values for treating liver infections, stomach ache, flatulence, constipation, inflammation, warts, colic, enteritis, fever, headache, and as a counter irritant. Its diverse phytochemicals have a wide range of valuable medicinal activities including hepatoprotective, anti-nociceptive, antioxidant, antiulcer, anticancer, anti-inflammatory, central analgesic, antidiabetic, antimicrobial, antiviral, and wound healing activity. AIM OF THE WORK: To provide a complete characterization of the composition of Ricinus communis leaves using ultra-performance liquid chromatography coupled with hybrid triple time-of-flight mass spectrometry (UPLC-Triple TOF-MS/MS) and different chromatographic techniques and to evaluate its antiviral potential using three mechanisms against three common viruses. MATERIALS AND METHODS: R. communis leaves were extracted with 70% methanol and further partitioned with solvents of increasing polarities: petroleum ether, dichloromethane (CH2Cl2), ethyl acetate, and n-butanol. The CH2Cl2 and n-butanol fractions were subjected to repeated chromatographic separation to isolate the phytochemicals, and their structures were elucidated using nuclear magnetic resonance spectroscopy. UPLC-Triple TOF-MS/MS was performed to determine the different phytochemicals in the ethyl acetate fraction. The antiviral activity of the extracts was investigated using the maximum nontoxic concentration of each against the challenge dose of the virus (CDV) and 1/10 and 1/100 dilutions of the CDV for Coxsackie B virus type 4 (COXB4), herpes simplex virus type 1 (HSV1), and hepatitis A virus (HAV) using Vero cell cultures that were treated according to three protocols to test for anti-replicative, protective, and anti-infective antiviral activity. Cell viability was evaluated using the MTT colorimetric assay and each experiment is repeated three times independently of each other. RESULTS: R. communis leaves possessed antiviral activity. Evaluation of the anti-replicative activity showed that all extracts possessed high anti-replicative activity against HAV especially methanol and methylene chloride fractions and moderate activity against COXB4; butanol > methylene chloride and ethyl acetate > methanol. All extracts showed protective activity against HAV, especially butanol extract, while methanol extracts showed higher non-significant antiviral protective activity against HSV1 vs Acyclovir. Almost no anti-infective effects were recorded for any extract against the studied viruses. CONCLUSION: The discriminatory effect against each virus by different mechanisms suggests the presence of different chemical compounds. The alkaloid and phenolic derivatives of the extracts of R. communis leaves may help develop a drug to prevent or treat common viral infections. Further investigations are recommended to define the bioactive antiviral properties of R. communis leaves.