Pro-Apoptotic Activity of Epi-Obtusane against Cervical Cancer: Nano Formulation, In Silico Molecular Docking, and Pharmacological Network Analysis

Cancer is a major disease that threatens human health all over the world. Intervention and prevention in premalignant processes are successful ways to prevent cancer from striking. On the other hand, the marine ecosystem is a treasure storehouse of promising bioactive metabolites. The use of such marine products can be optimized by selecting a suitable nanocarrier. Therefore, epi-obtusane, previously isolated from Aplysia oculifera, was investigated for its potential anticancer effects toward cervical cancer through a series of in vitro assays in HeLa cells using the MTT assay method. Additionally, the sesquiterpene was encapsulated within a liposomal formulation (size = 130.8 ± 50.3, PDI = 0.462, zeta potential -12.3 ± 2.3), and the antiproliferative potential of epi-obtusane was investigated against the human cervical cancer cell line HeLa before and after encapsulation with liposomes. Epi-obtusane exhibited a potent effect against the HeLa cell line, while the formulated molecule with liposomes increased the in vitro antiproliferative activity. Additionally, cell cycle arrest analysis, as well as the apoptosis assay, performed via FITC-Annexin-V/propidium iodide double staining (flow cytofluorimetry), were carried out. The pharmacological network enabled us to deliver further insights into the mechanism of epi-obtusane, suggesting that STAT3 might be targeted by the compound. Moreover, molecular docking showed a comparable binding score of the isolated compound towards the STAT3 SH2 domain. The targets possess an anticancer effect through the endometrial cancer pathway, regulation of DNA templated transcription, and nitric oxide synthase, as mentioned by the KEGG and ShinyGo 7.1 databases.

Pyronaridine as a Bromodomain-Containing Protein 4-N-Terminal Bromodomain (BRD4-BD1) Inhibitor: In Silico Database Mining, Molecular Docking, and Molecular Dynamics Simulation

BRD4 (bromodomain-containing protein 4) is an epigenetic reader that realizes histone proteins and promotes the transcription of genes linked to cancer progression and non-cancer diseases such as acute heart failure and severe inflammation. The highly conserved N-terminal bromodomain (BD1) recognizes acylated lysine residues to organize the expression of genes. As such, BD1 is essential for disrupting BRD4 interactions and is a promising target for cancer treatment. To identify new BD1 inhibitors, a SuperDRUG2 database that contains more than 4600 pharmaceutical compounds was screened using in silico techniques. The efficiency of the AutoDock Vina1.1.2 software to anticipate inhibitor-BRD4-BD1 binding poses was first evaluated based on the co-crystallized R6S ligand in complex with BRD4-BD1. From database screening, the most promising BRD4-BD1 inhibitors were subsequently submitted to molecular dynamics (MD) simulations integrated with an MM-GBSA approach. MM-GBSA computations indicated promising BD1 binding with a benzonaphthyridine derivative, pyronaridine (SD003509), with an energy prediction (ΔGbinding) of -42.7 kcal/mol in comparison with -41.5 kcal/mol for a positive control inhibitor (R6S). Pharmacokinetic properties predicted oral bioavailability for both ligands, while post-dynamic analyses of the BRD4-BD1 binding pocket demonstrated greater stability for pyronaridine. These results confirm that in silico studies can provide insight into novel protein-ligand regulators, specifically that pyronaridine is a potential cancer drug candidate.

Chetomin, a SARS-CoV-2 3C-like Protease (3CLpro) Inhibitor: In Silico Screening, Enzyme Docking, Molecular Dynamics and Pharmacokinetics Analysis

The emergence of the Coronavirus Disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to over 6 million deaths. The 3C-like protease (3CLpro) enzyme of the SARS-CoV-2 virus is an attractive druggable target for exploring therapeutic drug candidates to combat COVID-19 due to its key function in viral replication. Marine natural products (MNPs) have attracted considerable attention as alternative sources of antiviral drug candidates. In looking for potential 3CLpro inhibitors, the MNP database (>14,000 molecules) was virtually screened against 3CLpro with the assistance of molecular docking computations. The performance of AutoDock and OEDocking software in anticipating the ligand-3CLpro binding mode was first validated according to the available experimental data. Based on the docking scores, the most potent MNPs were further subjected to molecular dynamics (MD) simulations, and the binding affinities of those molecules were computed using the MM-GBSA approach. According to MM-GBSA//200 ns MD simulations, chetomin (UMHMNP1403367) exhibited a higher binding affinity against 3CLpro than XF7, with ΔGbinding values of −55.5 and −43.7 kcal/mol, respectively. The steadiness and tightness of chetomin with 3CLpro were evaluated, revealing the high stabilization of chetomin (UMHMNP1403367) inside the binding pocket of 3CLpro throughout 200 ns MD simulations. The physicochemical and pharmacokinetic features of chetomin were also predicted, and the oral bioavailability of chetomin was demonstrated. Furthermore, the potentiality of chetomin analogues −namely, chetomin A-D− as 3CLpro inhibitors was investigated. These results warrant further in vivo and in vitro assays of chetomin (UMHMNP1403367) as a promising anti-COVID-19 drug candidate.

Sarcoconvolutums F and G: Polyoxygenated Cembrane-Type Diterpenoids from Sarcophyton convolutum, a Red Sea Soft Coral

Natural products and chemical analogues are widely used in drug discovery, notably in cancer and infectious disease pharmacotherapy. Sarcophyton convolutum (Alcyoniidae) a Red Sea–derived soft coral has been shown to be a rich source of macrocyclic diterpenes and cyclized derivatives. Two previously undescribed polyoxygenated cembrane-type diterpenoids, sarcoconvolutums F (1) and G (2), as well as four identified analogues (3–6) together with a furan derivate (7) were isolated from a solvent extract. Compounds were identified by spectroscopic techniques, including NMR, HREIMS, and CD, together with close spectral comparisons of previously published data. Sarcoconvolutum F (1) contains a rare 1-peroxid-15-hydroxy-10-ene functionality. Isolated metabolites (1–7) were screened against lung adenocarcinoma (A549), cervical cancer (HeLa) and oral cavity carcinoma (HSC-2) lines. Compound 4 exhibited an IC₅₀ 56 µM and 55 µM against A549 and HSC-2 cells, respectively.

Paralemnolins X and Y, New Antimicrobial Sesquiterpenoids from the Soft Coral Paralemnalia thyrsoide

The organic extracts of the Red Sea soft coral Paralemnalia thyrsoides has led to the identification of two neolemnane-type sesquiterpenoids: paralemnolins X and Y (1, 2). In addition to these newly characterized compounds, ten known metabolites (3-12) were isolated. Previously reported compounds were elucidated by literature comparison of spectroscopic data (1D and 2D NMR as well as MS data). In vitro antimicrobial activity was investigated for compounds (1-12) against Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus niger. Compound 5 showed antimicrobial activity against all assayed microorganisms.

Oxygenated Cembrene Diterpenes from Sarcophyton convolutum: Cytotoxic Sarcoconvolutum A-E

The soft coral genus Sarcophyton contains the enzymatic machinery to synthesize a multitude of cembrene-type diterpenes. Herein, highly oxygenated cembrenoids, sarcoconvolutum A-E (1-5) were purified and characterized from an ethyl acetate extract of the red sea soft coral, Sarcophyton convolutum. Compounds were assemblies according to spectroscopic methods including FTIR, 1D- and 2D-NMR as well as HRMS. Metabolite cytotoxicity was tested against lung adenocarcinoma, cervical cancer, and oral-cavity carcinoma (A549, HeLa and HSC-2, respectively). The most cytotoxic compound, (4) was observed to be active against cell lines A549 and HSC-2 with IC50 values of 49.70 and 53.17 μM, respectively.

Lepidium sativum Secondary Metabolites (Essential Oils): In Vitro and In Silico Studies on Human Hepatocellular Carcinoma Cell Lines

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the greatest cause of cancer-related death in the world. Garden cress (Lepidium sativum) seeds have been proven to possess extraordinary antioxidant, anti-inflammatory, hypothermic, and analgesic properties. In this study, in vitro cytotoxic efficiency evaluation of L. sativum fractions was performed against two hepatocellular carcinoma cell lines (HuH-7 and HEPG-2), and the expression of some apoptotic genes was explored. In addition, the chemical composition of a potent extract of L. sativum was analyzed using gas chromatography coupled with mass spectrometry. Then, molecular docking analysis was implemented to identify the potential targets of the L. sativum components’ most potent extract. Overall, the n-hexane extract was the most potent against the two HCC cell lines. Moreover, these cytotoxicity levels were supported by the significant downregulation of EGFR and BCL2 gene expression levels and the upregulation of SMAD3, BAX, and P53 expression levels in both HuH-7 and HEPG2 cell lines. Regarding L. sativum’s chemical composition, GC–MS analysis of the n-hexane extract led to the identification of thirty compounds, including, mainly, hydrocarbons and terpenoids, as well as other volatile compounds. Furthermore, the binding affinities and interactions of the n-hexane fraction’s major metabolites were predicted against EGFR and BCL2 molecular targets using the molecular docking technique. These findings reveal the potential use of L. Sativum in the management of HCC.

Gastroprotection against Rat Ulcers by Nephthea Sterol Derivative

Different species belonging to the genus Nephthea (Acyonaceae) are a rich resource for bioactive secondary metabolites. The literature reveals that the gastroprotective effects of marine secondary metabolites have not been comprehensively studied in vivo. Hence, the present investigation aimed to examine and determine the anti-ulcer activity of 4α,24-dimethyl-5α-cholest-8β,18-dihydroxy,22E-en-3β-ol (ST-1) isolated from samples of a Nephthea species. This in vivo study was supported by in silico molecular docking and protein-protein interaction techniques. Oral administration of ST-1 reduced rat stomach ulcers with a concurrent increase in gastric mucosa. Molecular docking calculations against the H+/K+-ATPase transporter showed a higher binding affinity of ST-1, with a docking score value of -9.9 kcal/mol and a pKi value of 59.7 nM, compared to ranitidine (a commercial proton pump inhibitor, which gave values of -6.2 kcal/mol and 27.9 µM, respectively). The combined PEA-reactome analysis results revealed promising evidence of ST-1 potency as an anti-ulcer compound through significant modulation of the gene set controlling the PI3K signaling pathway, which subsequently plays a crucial role in signaling regarding epithelialization and tissue regeneration, tissue repairing and tissue remodeling. These results indicate a probable protective role for ST-1 against ethanol-induced gastric ulcers.

Blue Biotechnology: Computational Screening of Sarcophyton Cembranoid Diterpenes for SARS-CoV-2 Main Protease Inhibition

The coronavirus pandemic has affected more than 150 million people, while over 3.25 million people have died from the coronavirus disease 2019 (COVID-19). As there are no established therapies for COVID-19 treatment, drugs that inhibit viral replication are a promising target; specifically, the main protease (Mpro) that process CoV-encoded polyproteins serves as an Achilles heel for assembly of replication-transcription machinery as well as down-stream viral replication. In the search for potential antiviral drugs that target Mpro, a series of cembranoid diterpenes from the biologically active soft-coral genus Sarcophyton have been examined as SARS-CoV-2 Mpro inhibitors. Over 360 metabolites from the genus were screened using molecular docking calculations. Promising diterpenes were further characterized by molecular dynamics (MD) simulations based on molecular mechanics-generalized Born surface area (MM-GBSA) binding energy calculations. According to in silico calculations, five cembranoid diterpenes manifested adequate binding affinities as Mpro inhibitors with ΔGbinding < -33.0 kcal/mol. Binding energy and structural analyses of the most potent Sarcophyton inhibitor, bislatumlide A (340), was compared to darunavir, an HIV protease inhibitor that has been recently subjected to clinical-trial as an anti-COVID-19 drug. In silico analysis indicates that 340 has a higher binding affinity against Mpro than darunavir with ΔGbinding values of -43.8 and -34.8 kcal/mol, respectively throughout 100 ns MD simulations. Drug-likeness calculations revealed robust bioavailability and protein-protein interactions were identified for 340; biochemical signaling genes included ACE, MAPK14 and ESR1 as identified based on a STRING database. Pathway enrichment analysis combined with reactome mining revealed that 340 has the capability to re-modulate the p38 MAPK pathway hijacked by SARS-CoV-2 and antagonize injurious effects. These findings justify further in vivo and in vitro testing of 340 as an antiviral agent against SARS-CoV-2.

Bee Pollen: Current Status and Therapeutic Potential

Bee pollen is a combination of plant pollen and honeybee secretions and nectar. The Bible and ancient Egyptian texts are documented proof of its use in public health. It is considered a gold mine of nutrition due to its active components that have significant health and medicinal properties. Bee pollen contains bioactive compounds including proteins, amino acids, lipids, carbohydrates, minerals, vitamins, and polyphenols. The vital components of bee pollen enhance different bodily functions and offer protection against many diseases. It is generally marketed as a functional food with affordable and inexpensive prices with promising future industrial potentials. This review highlights the dietary properties of bee pollen and its influence on human health, and its applications in the food industry.

In Silico Mining of Terpenes from Red-Sea Invertebrates for SARS-CoV-2 Main Protease (Mpro) Inhibitors

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent for the COVID-19 pandemic, which generated more than 1.82 million deaths in 2020 alone, in addition to 83.8 million infections. Currently, there is no antiviral medication to treat COVID-19. In the search for drug leads, marine-derived metabolites are reported here as prospective SARS-CoV-2 inhibitors. Two hundred and twenty-seven terpene natural products isolated from the biodiverse Red-Sea ecosystem were screened for inhibitor activity against the SARS-CoV-2 main protease (Mpro) using molecular docking and molecular dynamics (MD) simulations combined with molecular mechanics/generalized Born surface area binding energy calculations. On the basis of in silico analyses, six terpenes demonstrated high potency as Mpro inhibitors with ΔGbinding ≤ -40.0 kcal/mol. The stability and binding affinity of the most potent metabolite, erylosides B, were compared to the human immunodeficiency virus protease inhibitor, lopinavir. Erylosides B showed greater binding affinity towards SARS-CoV-2 Mpro than lopinavir over 100 ns with ΔGbinding values of -51.9 vs. -33.6 kcal/mol, respectively. Protein-protein interactions indicate that erylosides B biochemical signaling shares gene components that mediate severe acute respiratory syndrome diseases, including the cytokine- and immune-signaling components BCL2L1, IL2, and PRKC. Pathway enrichment analysis and Boolean network modeling were performed towards a deep dissection and mining of the erylosides B target-function interactions. The current study identifies erylosides B as a promising anti-COVID-19 drug lead that warrants further in vitro and in vivo testing.

Comparative Study on the Essential Oils from Five Wild Egyptian Centaurea Species: Effective Extraction Techniques, Antimicrobial Activity and In-Silico Analyses

The genus Centaurea is recognized in folk medicine for anti-inflammatory, anti-itch, antitussive, purgative, astringent, and tonic activities. To study the chemical determinant for antimicrobial activity essential oils (EOs), five Centaurea species were analyzed including: C. scoparia, C. calcitrapa, C. glomerata, C. lipii and C. alexandrina. Conventional hydro-distillation (HD) and microwave-assisted extraction (MAE), as new green technologies, were compared for the extraction of essential oils. GC/MS analysis identified 120 EOs including mostly terpenoid except from C. lipii and C. alexandrina in which nonterpenoids were the major constituents. Major terpenoids included spathulenol, caryophyllene oxide and alloaromadendrene oxide-2. To probe antibacterial activity, potential EO inhibitors of a bacterial type II DNA topoisomerase, DNA gyrase B were screened via an in silico molecular docking approach. Spathulenol and alloaromadendrene oxide-2 possessed the best binding affinity in the ATP- binding pocket of Gyrase B enzyme. Principal component analysis and agglomerative hierarchical clustering were used for sample classification and revealed that sesquiterpenes contributed the most for accessions classification. In vitro antimicrobial activity against Staphylococcus aureus, Escherichia coli and Aspergillus niger for all EOs were also evaluated. EOs from C. lipii, C. glomerata and C. calcitrapa exhibited significant MIC against S. aureus with an MIC value of 31.25 µg/mL.

Marine Natural Products: A Source of Novel Anticancer Drugs

Cancer remains one of the most lethal diseases worldwide. There is an urgent need for new drugs with novel modes of action and thus considerable research has been conducted for new anticancer drugs from natural sources, especially plants, microbes and marine organisms. Marine populations represent reservoirs of novel bioactive metabolites with diverse groups of chemical structures. This review highlights the impact of marine organisms, with particular emphasis on marine plants, algae, bacteria, actinomycetes, fungi, sponges and soft corals. Anti-cancer effects of marine natural products in in vitro and in vivo studies were first introduced; their activity in the prevention of tumor formation and the related compound-induced apoptosis and cytotoxicities were tackled. The possible molecular mechanisms behind the biological effects are also presented. The review highlights the diversity of marine organisms, novel chemical structures, and chemical property space. Finally, therapeutic strategies and the present use of marine-derived components, its future direction and limitations are discussed.

Sarcoehrenbergilides D–F: cytotoxic cembrene diterpenoids from the soft coral Sarcophyton ehrenbergi

A solvent extract of the soft coral Sarcophyton ehrenbergi afforded cembrene diterpenoids, sarcoehrenbergilid D–F (1–3). Chemical structures were established by modern spectroscopic techniques with absolute stereochemistries determined by circular dichroism (CD) and time-dependent density functional theory electronic CD calculations (TDDFT-ECD). Cytotoxicity activities for 1–3 were evaluated against three human cancer cell lines: lung (A549), colon (Caco-2) and liver (HepG2).

A solvent extract of the soft coral Sarcophyton ehrenbergi afforded cembrene diterpenoids, sarcoehrenbergilid D–F (1–3).

Anti-inflammatory activity of highly oxygenated terpenoids from Achillea biebersteinii Afan

In continuation of our chemical investigation on some medicinal plants of the genus Achillea, chromatographic investigation of the methylene chloride/methanol (1:1) extract of the air-dried aerial part of Achillea biebersteinii Afan. (family Asteraceae) afforded a new natural monoterpene (2), in addition to two known sesquiterpenes (3 and 4). Compound 1 was isolated as light needle crystals. Structures were established on the basis of MS and NMR spectroscopic (1H, 13C, 1H-1H correlation spectroscopy, heteronuclear multiple-quantum coherence and heteronuclear multiple-bond correlation) data and in case of compound 1 were confirmed by X-ray analysis. All isolated compounds were examined for their anti-inflammatory activity to inhibit lipopolysaccharide-induced NO production in RAW264.7 macrophage cells. Compounds 3 and 4 produced a promising anti-inflammatory effect (76% and 80% inhibition, respectively). However, compounds 1 and 2 produced moderate inhibition of NO release recording a 41% and 36% inhibition of NO production, respectively.

Abstract 2188: Isolation and anticancer properties of some naturally occurring sesquiterpene lactones from Pulicaria undulate

Sesquiterpene lactones are natural compounds abundant in several plant families with a variety of biological activities such as antitumor effects. Camptothecin is famous topoisomerase interactive agent with anticancer properties against several types of malignancies. The purpose of this study is to investigate the potential chemotherapeutic effects of some naturally occurring sesquiterpene lactones isolated from Pulicaria undulate. Compounds with promising anticancer profile has been further investigated for potential chemomodulatory effects to camptothecin in different tumor cell types. Cytotoxicity of the isolated terpenoids were assessed against human breast adenocarcinoma (MCF7), human colorectal cancer (HCT116 and LS174T) and human hepatocellular carcinoma (HepG2) cells using sulpharhodamine-B assay after cell exposure for 72 h. Cytotoxic parameters (IC50 and R-fraction) were calculated from cell viability after fitting using Emax model. Two sesquiterpene lactones, 2α-hydroxy alantolactone and tomentosin, showed considerable cytotoxic profile against cell lines under investigation with IC50's ranging from 5 to 22 μM and from 14 to 39 μM, respectively. Treatment with camptothecin alone showed significant cytotoxicity with IC50's range from 0.13 to 1.5 μM in the same panel of cell lines. Equitoxic combination of tomentosin with camptothecin (combination ratio was 1:100) resulted in 60% reduction for the IC50 of camptothecin alone in HCT116 cells. On the other hand, equitoxic combination for hydroxy alantolactone with camptothecin did not significantly enhance the cytotoxicity of camptothecin against HCT116 cells. To explain the interactive characteristics of hydroxy alantolactone and tomentosin with camptothecin, annexin-V/PI staining coupled with flow cytometry analysis for apoptosis and necrosis was assessed after treatment with camptothecin alone or in combination with hydroxy alantolactone or tomentosin. Again, tomentosin combination with camptothecin significantly increased apoptotic as well as necrotic cell populations compared to camptothecin treatment alone by 2-3 folds. On the other hand, combination of camptothecin with hydroxy alantolactone significantly increased apoptotic cell population with reciprocal decrease in necrotic cell population. In conclusion, hydroxy alantolactone and tomentosin might be promising anticancer agents. However, further molecular investigation is required to understand the nature of interaction between the isolated sesquiterpene lactones and cornerstone chemotherapeutics such as camptothecin.

Citation Format: Mohammed M. Arab, Fahad A. Al-Abbasi, Mohamed-Elamir F. Hegazy, Ali M. El-Halawany, Ahmed M. Al-Abd. Isolation and anticancer properties of some naturally occurring sesquiterpene lactones from Pulicaria undulate. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2188.

Abstract 4846: Chemotherapeutic and chemomodulatory effects of naturally occurring tetrahydrofuran type terpenoid

Naturally occurring terpenoid compounds are diverse active constituent in several plants and known of their potential anticancer activities. Camptothecin (CPT) is a topoisomerase inhibitor agent with well documented anti-neoplastic activity against several types of tumors. The purpose of this study is to investigate the potential chemotherapeutic effects of some terpenoid compounds isolated from Salvia africana lutea, Stachys aegyptiaca, Tanacetum sinaicum. Terpenoid compounds with promising anticancer profile has been further investigated for potential chemomodulatory effects to CPT against different tumor cell types. Cytotoxicity of the isolated terpenoids were assessed against human breast adenocarcinoma (MCF7), human colorectal cancer (HCT116 and LS174T) and human hepatocellular carcinoma (HepG2) cells using sulpharhodamine-B assay after cell exposure for 72 h. Cytotoxic parameters (IC50 and R-fraction) were calculated from cell viability after fitting to Emax mathematical model. The tetrahydrofuran type terpenoid, (R,E)-6-hydroxy-6-methyl-2-((2S,5R)-methyl-5-vinyltetrahydrofuran-2-yl)hept-4-en-3-one (TSS-7), isolated from Tanacetum sinaicum showed considerable cytotoxicity with IC50 ranging from 49 to 70 μM in all tested cell lines. On the other hand, IC50 of CPT ranged from 0.13 to 1.5 μM in the same cell lines under investigation. Combination index analysis (CI-value) for TSS-7 with CPT showed synergistic relationship in MCF7, HCT116 and HepG2 (CI-values were 0.17, 0.17 and 0.39 respectively). However, the same combination of TSS-7 and CPT against LS174T cells showed antagonistic relationship (CI-value of 1.2). Further investigation for apoptosis/necrosis assessment using annexin-V/PI staining was undertaken for single and combination treatment of CPT and TSS-7. In HCT116 cells, TSS-7 combination with CPT significantly increased apoptotic and necrotic cells compared to CPT treatment alone. However, in LS174T cells, TSS-7 combination with CPT significantly decreased apoptotic and necrotic cells compared to CPT treatment alone. Cell cycle analysis using DNA cytometry showed strong G2/M arrest induced by CPT treatment. Yet, TSS-7 increased cell population in S-phase and to a lesser extend in G2/M-phase which might be the reason for temporal synergism/antagonism of TSS-7 and CPT in different cell lines. In conclusion, TSS-7 could be considered promising anticancer chemomodulatory terpenoid compound which requires further molecular investigations to elucidate its sub-cellular molecular target.

Citation Format: Eman M. Atiya, Fahad A. Al-Abbasi, Mohamed-Elamir F. Hegazy, Ali M. El-Halawany, Ahmed M. Al-Abd. Chemotherapeutic and chemomodulatory effects of naturally occurring tetrahydrofuran type terpenoid. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4846.

Microbial biotransformation as a tool for drug development based on natural products from mevalonic acid pathway: A review

Natural products are structurally and biologically interesting metabolites, but they have been isolated in minute amounts. The syntheses of such natural products help in obtaining them in bulk amounts. The recognition of microbial biotransformation as important manufacturing tool has increased in chemical and pharmaceutical industries. In recent years, microbial transformation is increasing significantly from limited interest into highly active area in green chemistry including preparation of pharmaceutical products. This is the first review published on the usage of microbial biocatalysts for some natural product classes and natural product drugs.

Cytotoxic saponin poliusaposide from Teucrium polium

Three saponin glycosides have been isolated and characterized from Teucrium polium L. (Lamiaceae).

Anti-inflammatory sesquiterpenes from the medicinal herb Tanacetum sinaicum

New sesquiterpenes tanacetolide A–C (1–3) were isolated from aTanacetum sinaicumextract together with known compounds (4–10).

Biotransformation of Progesterone by Cultured Cells of Marchantia polymorpha

Cell suspensions of Marchantia polymorpha hydrogenate progesterone to 5α-pregnane-3,20- dione. Structure elucidation of the product was achieved by comprehensive NMR analyses.

Biological Activity of a Phloroglucinol Glucoside Derivative from Conyza aegyptiaca

The phloroglucinol glucoside derivative [2,4-dihydroxy-6-(β-D-glucopyranosyloxy)phenyl]- butan-1-one (1), roseoside (2), and kaempferol-3-O-β-D-glucopyranoside (3) were isolated from the aerial parts of Conyza aegyptiaca (L.). To the best of our knowledge, this is the first isolation of compounds 1 - 3 from C. aegyptiaca. Their structures were determined by spectroscopic techniques including, IR, HR-EIMS, and extensive 500 MHz 1D- and 2D-NMR analyses (1H, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC experiments). The antioxidant activity of 1, using the DPPH assay, was investigated; in addition, 1 was investigated against different types of cell lines, including Hep-G2, HCT-116, and RAW 264.7 for its cytotoxic effects. Also, this is the first report on the activity of 1.

Cytotoxicity of 3-O-(β-D-Glucopyranosyl) Etioline, a Steroidal Alkaloid from Solanum diphyllum L

In continuation of our interest in phytochemical screening of the Egyptian flora for potential drugs, the reinvestigation of the methanolic extract of the roots of Solanum diphyllum, which grows naturally in the south of Egypt and is recorded as new to the Egyptian flora, afforded an interesting, highly cytotoxic compound, named 3-O-(β-D-glucopyranosyl) etioline [(25S)-22,26-epimino-3β-(β-D-glucopyranosyloxy) cholesta-5,22(N)-dien-16α-ol]. The chemical structure of this compound was determined by comprehensive NMR studies, including DEPT, COSY, HMQC, and MS. The compound exhibited high cytotoxic effects against the cervical cancer cell line, Hela cells, with an IC50 value of 150 μg/mL

Cytotoxic Cembranoids from the Red Sea Soft Coral Sarcophyton glaucum

One new cembrane diterpene, 2 R,7 R,8 R-dihydroxydeepoxysarcophine (1), together with three known compounds, 7α,8β-dihydroxy-deepoxysarcophine (2), 7β-acetoxy-8α-hydroxydeepoxysarcophine (3), and sarcophine (4), have been isolated from the Red Sea soft coral Sarcophyton glaucum. Their structures were determined using 1D and 2D NMR spectroscopy. 7β-Acetoxy-8α-hydroxydeepoxysarcophine (3) exhibits cytotoxic activity against HepG2, HCT-116, and HeLa cells with IC50 values of 3.6, 2.3, and 6.7 μg/mL, respectively.

A new 14,15-dinor-labdane Glucoside from Crassocephalum Mannii

A new 14,15-dinor-labdane glucoside, named crassoside A (1), was isolated from the aerial parts of Crassocephalum mannii. The structure of 1 was elucidated on the basis of spectroscopic analysis (1H NMR, 13C NMR, HMQC, HMBC and NOEs). Compound 1 demonstrated a low inhibitory effect against COX-1, but was inactive against COX-2.

Anti-inflammatory Activity of New Guaiane Acid Derivatives from Achillea Coarctata

Chromatographic investigation of the methylene chloride/methanol extract of aerial parts of Achillea coarctata afforded two new guaiane acid derivatives, 1α,6α,8α-trihydroxy-5α,7βH-guaia-3,10(14),11(13)-trien-12-oic acid (1) and 1α,6α,8α-trihydroxy-5α,7βH-guaia-3,9,11(13)-trien-12-oic acid (2), in addition to three known compounds, ligustolide-A (3), arteludovicinolide-A (4) and austricin (5). Structures were elucidated by spectroscopic analyses including: 1H and 13C NMR, COSY, HMQC, HMBC and NOESY NMR spectroscopy, as well as MS analysis. Proliferation of beneficial macrophages was significantly enhanced by treatment with 1 and 2. Additionally, treatment with compounds 2 and 4 led to a potentially significant inhibition in nitric oxide generation from raw murine macrophage 264.7, which was stimulated by bacterial lipopolysaccharide. Compounds 2 and 4 exhibited anti-inflammatory properties, based on a nitric oxide assay.

Genus Chrysothamnus: A Source of Bioactive Compounds

This review is written to take into account the rapid development in the taxonomy and phytochemistry of Chrysothamnus species. The article reviews the usage and biological activities of Chrysothamnus compounds, as well as recent progress regarding the use of this genus in clinical research.

Ferulol and epi-Samarcandin, Two New Sesquiterpene Coumarins from Ferula Sinaica

Re-investigation of the methylene chloride extract of the root of Ferula sinaica gave a sesquiterpene coumarin with a rare carbon skeleton and 3′,9′-di- epi-samarcandin. The structure elucidation was determined by MS; 1H- and 13C- 1D and 2D NMR spectral data.