Abdelaaty A. Shahat

Chemical Composition, Antimicrobial and Antioxidant Activities of Essential Oils from Organically Cultivated Fennel Cultivars

Essential oils of the fruits of three organically grown cultivars of Egyptian fennel (Foeniculum vulgare var. azoricum, Foeniculum vulgare var. dulce and Foeniculum vulgare var. vulgare) were examined for their chemical constituents, antimicrobial and antioxidant activities. Gas chromatography/mass spectrometry analysis of the essential oils revealed the presence of 18 major monoterpenoids in all three cultivars but their percentage in each oil were greatly different. trans-Anethole, estragole, fenchone and limonene were highly abundant in all of the examined oils. Antioxidant activities of the essential oils were evaluated using the DPPH radical scavenging, lipid peroxidation and metal chelating assays. Essential oils from the azoricum and dulce cultivars were more effective antioxidants than that from the vulgare cultivar. Antimicrobial activities of each oil were measured against two species of fungi, two species of Gram negative and two species of Gram positive bacteria. All three cultivars showed similar antimicrobial activity.

Antibacterial activity and cytotoxicity of selected Egyptian medicinal plants.

Medicinal plants have been used as a source of remedies since ancient times in Egypt. The present study was designed to investigate the antibacterial activity and the cytotoxicity of the organic extracts from 16 selected medicinal plants of Egypt. The study was also extended to the isolation of the antiproliferative compound jaeschkeanadiol p-hydroxybenzoate (FH-25) from Ferula hermonis. The microbroth dilution was used to determine the minimal inhibitory concentration (MIC) of the samples against twelve bacterial strains belonging to four species, Providencia stuartii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli, while a resazurin assay was used to assess the cytotoxicity of the extracts on the human pancreatic cancer cell line MiaPaCa-2, breast cancer cell line MCF-7, CCRF-CEM leukemia cells, and their multidrug resistant subline, CEM/ADR5000. The results of the MIC determination indicated that all the studied crude extracts were able to inhibit the growth of at least one of the tested bacterial species, the best activity being recorded with the crude extracts from F. hermonis and Vitis vinifera, whichwere active against 91.7% and 83.3% of the studied bacteria, respectively. The lowest MIC value of 128 μg/mL was recorded against P. stuartii ATCC 29916 and E. coli ATCC 10536 with the extract from V. vinifera and Commiphora molmol, respectively. In the cytotoxicity study, IC50 values below 20 μg/mL were recorded for the crude extract of F. hermonis on all four studied cancer cell lines. FH-25 also showed good cytotoxicity against MCF-7 cells (IC50: 2.47 μg/mL). Finally, the results of the present investigation provided supportive data for the possible use of the plant extracts investigated herein, mostly F. hermonis and V. vinifera in the treatment of bacterial infections and jaeschkeanadiol p-hydroxybenzoate in the control of cancer diseases.

Procyanidins from Adansonia digitata

Abstract The 80% methanol of the pericarp of the fruits of Adansonia digitata. L. (Bombaceae) was found to contain proanthocyanidins as major compounds, vi.z., (-)-epicatechin, epicatechin-(4 → β.8)-epicatechin B2, epicatechin-(4 → β.6)-epicatechin B5, epicatechin-(2β. → O → 7, 4β. → 8)-epicatechin A2, and epicatechin-(4 → β.8)-epicatechin-(4 → β.8)-epicatechin C1. All the isolated compounds were isolated by open-column liquid chromatography (CC) using Sephadex-LH 20 as stationary phase. Elution of the column was performed with EtOH. The structures of these compounds were elucidated by means of TLC, ESI-MS, and 1D and 2D NMR spectroscopy.

Bioactive Hydroperoxyl Cembranoids from the Red Sea Soft Coral Sarcophyton glaucum

A chemical investigation of an ethyl acetate extract of the Red Sea soft coral Sarcophyton glaucum has led to the isolation of two peroxide diterpenes, 11(S) hydroperoxylsarcoph-12(20)-ene (1), and 12(S)-hydroperoxylsarcoph-10-ene (2), as well as 8-epi-sarcophinone (3). In addition to these three new compounds, two known structures were identified including: ent-sarcophine (4) and sarcophine (5). Structures were elucidated by spectroscopic analysis, with the relative configuration of 1 and 2 confirmed by X-ray diffraction. Isolated compounds were found to be inhibitors of cytochrome P450 1A activity as well as inducers of glutathione S-transferases (GST), quinone reductase (QR), and epoxide hydrolase (mEH) establishing chemo-preventive and tumor anti-initiating activity for these characterized metabolites.

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

Graphical abstract

Phenolic compounds from Foeniculum vulgare (Subsp. Piperitum) (Apiaceae) herb and evaluation of hepatoprotective antioxidant activity

Objective: The study was designed to evaluate the antioxidant and hepatoprotective activities of the 80% methanolic extract as well as the ethyl acetate (EtOAc) and butanol (BuOH) fractions of the wild fennel (Foeniculum vulgare (Subsp; Piperitum)) and cultivated fennel (F. vulgare var. azoricum). In addition, quantification of the total phenolic content in the 80% methanol extract of fennel wild and cultivated herbs is measured. Materials and Methods: An amount of 400 g of air dried powdered herb of wild and cultivated fennel were sonicated with aqueous methanol (80%), successively extracted with Hexane, EtOAc, and n-BuOH. The EtOAc and n-BuOH were subjected to repeated column chromatography on silica gel and Sephadex LH-20. The antioxidant effect was determined in vitro using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Hepatoprotective activity was carried out using a Wistar male rat (250–300 g). Total phenolic and flavonoid contents were determined as chlorogenic acid and rutin equivalents, respectively. Results: Two phenolic compounds, i.e., 3,4-dihydroxy-phenethylalchohol-6-O-caffeoyl-β-D-glucopyranoside and 3΄,8΄-binaringenin were isolated from the fennel wild herb, their structures were elucidated by spectral methods including 1D NMR, 2D NMR, and UV. The EtOAc and BuOH fractions of wild fennel were found to exhibit a radical scavenging activity higher than those of cultivated fennel. An in vitro method of rat hepatocytes monolayer culture was used for the investigation of hepatotoxic effects of the 80% methanol extract on the wild and cultivated fennel, which were >1000 and 1000 μg/mL, respectively. As well as, their hepatoprotective effect against the toxic effect of paracetamol (25 mM) was exerted at 12.5 μg/mL concentration. Conclusions: Fennel (F. Vulgare) is a widespread plant species commonly used as a spice and flavoring. The results obtained in this study indicated that the fennel (F. vulgare) herb is a potential source of natural antioxidant. Two phenolic compounds, i.e. 3,4-dihydroxy-phenethylalchohol-6-O-caffeoyl-β-D-glucopyranoside (A) and 3΄,8΄-binaringenin (B) were isolated from the fennel wild herb for the first time.

The Application of Liquid Chromatography-Electrospray Ionization Mass Spectrometry and Collision-Induced Dissociation in the Structural Characterization of Acylated Flavonol O-Glycosides from the Seeds of Carrichtera Annua:

The flavonoid fraction from the seeds of Carrichtera annua was studied using high-performance liquid chromatography simultaneously coupled to a photodiode array detector (LC/UV-DAD) and a mass spectrometer equipped with an electrospray source (LC/ESI-MS). Collision-induced dissociation (CID) mass spectral data obtained off-line by nanospray (nano-ESI) analysis provided a wealth of complementary structural information, which was consistent with structures established by NMR or led to the proposal of base structures of the flavonol O-glycosides present in the Carrichtera annua seed extract. The flavonoid fraction was found to contain 12 structurally related flavonol O-glycosides. Eleven flavonoids, of which several were new compounds, were acylated with one or more benzoyl, feruloyl or sinapoyl groups. These acyl groups gave rise to characteristic product ions in the [M + H]+ and [M + Na]+ CID spectra as well as to radicalar acid-related product ions at high-energy collisional activation. In addition to the characterization of the acyl substituents, the mass spectral data allowed the identification of the aglycone, the determination of the base structure and the differentiation of several positional isomers.

Biochemical and Neurotransmitters Changes Associated with Tramadol in Streptozotocin-Induced Diabetes in Rats

The incidence of diabetes is increasing worldwide. Chronic neuropathic pain occurs in approximately 25% of diabetic patients. Tramadol, an atypical analgesic with a unique dual mechanism of action, is used in the management of painful diabetic neuropathy. It acts on monoamine transporters to inhibit the reuptake of norepinephrine (NE), serotonin (5-HT), and dopamine (DA). The purpose of this study was to evaluate the effects of diabetes on the brain neurotransmitter alterations induced by tramadol in rats, and to study the hepatic and renal toxicities of the drug. Eighty Sprague-Dawley rats were divided randomly into two sets: the normal set and the diabetic set. Diabetes was induced in rats. Tramadol was administered orally once daily for 28 days. The levels of DA, NE, and 5-HT in cerebral cortex, thalamus/hypothalamus, midbrain, and brainstem were evaluated in rats. In addition, the renal toxicity and histopathological effects of the drug were assessed. The induction of diabetes altered neurotransmitter levels. Oral administration of tramadol significantly decreased the neurotransmitter levels. Diabetes significantly altered the effects of tramadol in all brain regions. Tramadol affected function and histology of the liver and kidney. The clinical effects of tramadol in diabetic patients should be stressed.

Estrogenic Activity of Chemical Constituents from Tephrosia candida

In a continued investigation of medicinal plants from the genus Tephrosia, phytochemical analysis of a methylene chloride-methanol (1:1) extract of the air-dried aerial parts of Tephrosia candida afforded two new 8-prenylated flavonoids, namely, tephrocandidins A (1) and B (2), a new prenylated chalcone, candidachalcone (3), a new sesquiterpene (4), and a previously reported pea flavonoid phytoalexin, pisatin (5). The structures of 1-4 were established by spectroscopic methods, including HREIMS, and 1H, 13C, DEPT, HMQC, and HMBC NMR experiments. The most potent estrogenic activity of these isolated natural products in an estrogen receptor (ERα) competitive-binding assay was for 3, which exhibited an IC50 value of 80 μM, compared with 18 nM for the natural steroid 17β-estradiol. Results were interpreted via virtual docking of isolated compounds to an ERα crystal structure.

Chemical composition and antimicrobial activities of the essential oil from the seeds of Enterolobium contortisiliquum (Leguminosae).

Seeds of Enterolobium contortisiliquum were subjected to steam distillation to obtain a light yellow essential oil in a yield of 3 ml/kg of seeds. The major components of the oil were identified using gas chromatography/mass spectrometry (GC-MS) and were furfural, limonene, linalool, estragole, carvone, and apiole with carvone representing more than 50% of the total composition. Antimicrobial activities of the essential oil were determined against four species of gram positive bacteria (Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Micrococcus luteus) and two gram negative bacteria (Klebsiella pneumoniae, Serratia Marcescencs). The essential oil inhibited the growth of all tested bacteria but was most effective against the gram positive bacteria. Chemicals that are responsible for the antibacterial effect of the essential oil were determined using the bio-autography thin layer chromatography (TLC) technique. The active compounds responsible for the activity were found to be carvone and estragole.