Ehab S. Elkhayat

Portulene, a new diterpene from Portulaca oleracea L.

Chromatographic fractionation of the chloroform extract of Portulaca oleracea L. growing in Egypt afforded a new clerodene diterpene portulene (1), in addition to the known compounds lupeol (2), β-sitosterol (3), and daucosterol (4), which were reported for the first time from the title plant. The structures of the isolated compounds were unambiguously established through 1D, 2D, and mass spectral analyses. Co-treatment of CCl4 hepatic injured rats with 70% alcohol extract of P. oleracea significantly restored the hepatic marker enzymes and total bilirubin to near-normal values, which demonstrated hepatoprotective activity. In addition, the P. oleracea extract showed antibacterial and antifungal activities.

Terrenolide S, a new antileishmanial butenolide from the endophytic fungus Aspergillus terreus

Abstract Terrenolide S, a new butenolide derivative (6), together with six known compounds: (22E,24R)-stigmasta-5,7,22-trien-3-β-ol (1), stigmast-4-ene-3-one (2), stigmasta-4,6,8(14),22-tetraen-3-one (3), terretonin A (4), terretonin (5) and butyrolactone VI (7) have been isolated from the endophytic fungus Aspergillus terreus isolated from the roots of Carthamus lanatus (Asteraceae). Their structures were established by extensive spectroscopic analyses (1D, 2D NMR and HRESIMS), as well as optical rotation measurement and comparison with literature data. Compound 1 displayed a potent activity towards methicillin-resistant Staphylococcus aureus (MRSA) and Cryptococcus neoformans with IC50 values of 2.29 and 10.68 µM, respectively. Moreover, 1, 2 and 6 exhibited antileishmanial activity towards Leishmania donovani with IC50 values of 11.24, 15.32 and 27.27 µM, respectively and IC90 values of 14.68, 40.56 and 167.03 µM, respectively. Graphical Abstract

Fusaripeptide A: new antifungal and anti-malarial cyclodepsipeptide from the endophytic fungus Fusarium sp.

Abstract From the culture of the endophytic fungus Fusarium sp. isolated from the roots of Mentha longifolia L. (Labiatae) growing in Saudi Arabia, a new cyclodepsipeptide, namely fusaripeptide A (1), along with three known compounds adenosine (2), 2[(2-hydroxypropionyl)amino]benzamide (3), and cyclopentanol (4), have been isolated. Their structures were determined, using extensive 1D and 2D NMR and HRESI and GC mass spectral data. That is the first report for the isolation of compound 4 from natural source. In addition, compounds 2 and 3 are reported here for the first time from Fusarium sp. The absolute configuration of the amino acid residues of 1 was assigned by chiral GCMS and Marfey’s analysis after acid hydrolysis. Fusaripeptide A differs from the reported ones from Fusarium sp. in the length of fatty acidic alkyl chain. Compound 1 was evaluated for its antifungal, anti-malarial, and cytotoxic activities. It exhibited potent antifungal activity toward C. albicans, C. glabrata, C. krusei, and A. fumigates with IC50 values of 0.11, 0.24, 0.19, and 0.14 μM, respectively. Furthermore, it had significant anti-malarial activity toward P. falciparum (D6 clone) with IC50 value of 0.34 μM. However, it showed cytotoxic activity toward the tested cell lines.

Iotrochotamides I and II: New ceramides from the Indonesian sponge Iotrochota purpurea

Our search for biologically active marine natural products led to the isolation of two new ceramides, iotrochotamide I (1) and iotrochotamide II (2), together with three known 6-bromoindole alkaloids (6-bromo-1H-indole-3-carbaldehyde (3), 6-bromo-1H-indole-3-carboxylic acid methyl ester (4), and 6-bromo-1H-indole-3-carboxylic acid ethyl ester (5)) from the sponge Iotrochota purpurea collected in Indonesia. The structure elucidation of these compounds was secured by spectroscopic methods (1H, 13C, DEPT, COSY, HMQC and HMBC), accurate mass measurements (ESI, EI and GS-MS) as well as comparison with known compounds.

Cytotoxic and Antibacterial Constituents from the Roots of Sonchus oleraceus L. Growing in Egypt

Phytochemical study of the roots of Sonchus oleraceus L. (Astraceae) Growing in Egypt, afforded loliolide 1 for the first time from the genus Sonchus in addition to 15-O- β -glucopyranosyl-11 β ,13-dihydrourospermal A 2 , ursolic acid 3 , lupeol 4 and β-sitosterol- 3-O-glucopyranoside 5 for the fi rst time from the plant. The biological evaluation of the isolated compounds showed cytotoxic activity of 1 and 2 against PC33 and L5187Y cell lines, in addition to antibacterial activity against S.aureus , B. subtilis , E. Coli and N. gohnorea . The structures of the compounds were elucidated using 1D ( 1 H and 13C), 2D (H-H COSY, H S QC and HMBC) NMR and MS spectroscopic data.

Fusarithioamide B, a new benzamide derivative from the endophytic fungus Fusarium chlamydosporium with potent cytotoxic and antimicrobial activities

Fusarithioamide B (6), a new aminobenzamide derivative with unprecedented carbon skeleton and five known metabolites: stigmast-4-ene-3-one (1), stigmasta-4,6,8(14),22-tetraen-3-one (2), p-hydroxyacetophenone (3), tyrosol (4), and fusarithioamide A (5) were separated from Fusarium chlamydosporium EtOAc extract isolated from Anvillea garcinii (Burm.f.) DC. leaves (Asteraceae). The structure elucidation and completeassignment of the isolated metabolites were performed mainly by the aid of various NMR and MS data. Fusarithioamide B (6) has been assessed for antibacterial and antifungal activities towards various microbial strains by disc diffusion assay. It exhibited selective antifungal activity towards C. albicans (MIC 1.9 µg/ml and IZD 14.5 mm), comparing to clotrimazole (MIC 2.8 µg/ml and IZD 17.9 mm). Also, it possessed high antibacterial potential towards E. coli, B. cereus, and S. aureus compared to ciprofloxacin. Furthermore, 6 was tested for the in vitro cytotoxic effect against KB, HCT-116, BT-549, MCF-7, SKOV-3, and SK-MEL cell lines. It had selective and potent effect towards BT-549, MCF-7, SKOV-3, and HCT-116 cell lines with IC50s 0.09, 0.21, 1.23, and 0.59 μM, respectively compared to doxorubicin (IC50s 0.046, 0.05, 0.321, and 0.24 μM, respectively). Fusarithioamide B may provide a lead molecule for future developing of antitumor and antimicrobial agents.

Potential Antidepressant Constituents of Nigella sativa Seeds.

Background: Nigella sativa Linn. is well known seed in the Middle East, Asia, and the Far East as a natural remedy for many ailments and as a flavoring agent proclaimed medicinal usage dating back to the ancient Egyptians, Greeks, and Romans. An authentic saying of the Prophet Muhammad (Peace Be Upon Him) about black seed is also quoted in Al-Bukhari. Objective: This study was carried out to evaluate the antidepressant effect and isolate the potential antidepressant constituents of the polar extract of N. sativa seeds. Materials and Methods: The antidepressant effect was evaluated through the immobility duration in tail suspension and forced swim tests (FSTs). Albino mice were orally treated with N. sativa polar extract and its RP-18 column chromatography fractions (50 and 100 mg/kg,). Results: The polar extract and two of its sub-fractions were significantly able to decrease the immobility time of mice when subjected to both tail suspension and FSTs, the effects are comparable to standard drug (Sertraline, 5 mg/kg). However, these treatments did not affect the number of crossings and rearing in the open field test. Phytochemical investigation of the two active fractions led to the isolation of quercetin-3-O-α-L-rhamnopyranoside 1, quercetin-7-O-β-D-gluco- pyranoside 2, tauroside E 3, and sapindoside B as the potential antidepressant constituents.