Zedan Z. Ibraheim

Antiparasitic antioxidant phenylpropanoids and iridoid glycosides from Tecoma mollis.

A radical scavenging guided phytochemical study on the stem bark of Tecoma mollis afforded seven active phenylpropanoid glycosides (1-7), including a new one (4), and one iridoid (8). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Compounds (1-7) displayed promising antioxidant activity (DPPH assay) in relation to ascorbic acid (positive control). The antimicrobial activity for compounds (1-8) was evaluated against five bacterial and five fungal strains. The isolated compounds exhibited nonselective weak to moderate antimicrobial activity. The highest antileishmanial activity against Leishmania donovani was observed for compound (7) with an IC₅₀ value of 6.71 μg/ml, using pentamidine and amphotericin B as drug controls. Compound (5) exhibited moderate antimalarial activity (45% inhibition) against chloroquine sensitive (D6) clones of Plasmodium falciparum.

Phytochemical and biological studies of Adiantum capillus-veneris L.

Chromatographic fractionation of the alcoholic extract of the dried fronds of Adiantum capillus-veneris L. (Adiantaceae) yielded seven compounds: four triterpenoidal compounds belonging to adiantane and filicane groups were isolated from the hexane fraction and identified as isoadiantone (1); isoadiantol-B (2); 3-methoxy-4-hydroxyfilicane (3) and 3,4-dihydroxyfilicane (4) and three flavonoids were isolated from the ethyl acetate fraction and identified as: quercetin (5), quercetin-3-O-glucoside (6) and quercetin-3-O-rutinoside (rutin) (7). The identification of the isolated compounds has been established through their physical, chemical and spectroscopic methods including IR, (1)H NMR, (13)C NMR, HSQC, HMBC, NOESY and MS. Biological studies of the total alcoholic extract, hexane fraction and some of the isolated compounds showed an anti-inflammatory activity while the hypoglycemic study of the total alcoholic extract showed a significant activity.

Antimicrobial Antioxidant Daucane Sesquiterpenes from Ferula hermonis Boiss

Seventeen daucane sesquiterpenoid esters, including a new one (4), were isolated from the root of Ferula hermonis Boiss. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidence and correlated with known compounds. The relative stereochemistry of the new compound was determined using 2D NOESY and the most stable and the lowest energy conformation was determined using molecular modelling. The antimicrobial activity was evaluated by determination of MIC using the broth microdilution method against six bacterial strains and one fungal strain (Pseudomonas aeruginosa PAO1, Escherichia coli, Bacillus subtilis ATCC6633, Mycobacterium bovis BCG Pasteur, Mycobacterium tuberculosis H37Rv, Staphylococcus aureus ATCC6538 and Candida albicans SC5314). There was a significant indication that compounds 15, 16, 17 demonstrated potent activity against Gram +ve (S. aureus, B. subtilis), as well as Mycobacterium strains M. bovis BCG and M. tuberculosis H37Rv. None of the isolated compounds exhibited a significant antifungal activity. In the antioxidant study using the DPPH assay method, the highest radical scavenging activity was observed for compounds 15, 16, 17. Copyright

In Vitro Effects of Some Herbs Used in Egyptian Traditional Medicine on Viability of Protoscolices of Hydatid Cysts

The present work evaluated the effects of alcoholic extracts of salvia (Salvia officinalis), thyme (Thymus vulgaris), and 2 pure compounds (thymol and menthol) on the viability of Echinococcus granulosus protoscolices in vitro. Four different concentrations of each extract (2,500, 1,500, 1,000, and 500 µg/ml) and 3 different concentrations each of thymol and menthol (50, 10, and 1 µg/ml) were used. Concentration of 2,500 µg/ml of both extracts showed a significant protoscolicidal activity on the 6th day. Complete loss of viability of protoscolices occurred with 500 µg/ml concentration of both extracts at day 6 and day 7 post-treatment (PT), respectively. Pure compounds, i.e., menthol and thymol, showed potent effects with 50 µg/ml concentration at day 2 and day 5 PT, respectively. These effects were compared with those of albendazole sulfoxide (800 µg/ml), a commonly used treatment drug for hydatidosis. Krebs-Ringer solution and the hydatid cystic fluid at a ratio of 4:1 was a good preservative solution which kept the protoscolices viable for 15 days.

Further saponins from Taverniera aegyptiaca.

From the saponin fraction of the total methanolic extract of the dried root and stem barks of Taverniera aegyptiaca Boiss, six new triterpenoidal saponins of oleanane type were isolated and identified as 28-methyl serratagenate-3-beta-O-beta-xylopyranosyl (1-->2)-beta-glucopyranoside (2), 28-methyl serratagenate 3-beta-O-alpha-rhamnopyranosyl (1-->2)-beta-glucopyranoside (3), 3beta-O-alpha-rhamnopyranosyl (1-->2) beta-glucopyranosyl-olean-11,13(18)-dien-1beta, 3beta, 22beta-triol (4), 3beta-O-beta-glucopyranosyl (1-->2)-beta-glucuronopyranosylolean-11,13(18)-dien-1beta,3beta,22beta-triol (5), 3beta-O-beta-xylopyranosyl(1-->2)-beta-glucuronopyranosylolean-11,13(18)-dien-1beta,3beta,22beta-triol (6), 3beta-O-alpha-rhamnopyranosyl (1-->2)-beta-glucuronopyranosylolean-11,13(18)-dien-1beta, 3beta, 22beta-triol (7) together with the known oleanolic acid 3-beta-O-beta-glucoside (1). The identification of the isolated compounds was done on the basis of chemical and spectral evidences.

Effect of myrrh and thyme on Trichinella spiralis enteral and parenteral phases with inducible nitric oxide expression in mice.

Trichinellosis is a serious disease with no satisfactory treatment. We aimed to assess the effect of myrrh (Commiphora molmol) and, for the first time, thyme (Thymus vulgaris L.) against enteral and encysted (parenteral) phases of Trichinella spiralis in mice compared with albendazole, and detect their effect on inducible nitric oxide synthase (iNOS) expression. Oral administration of 500 mg/kg of myrrh and thyme led to adult reduction (90.9%, 79.4%), while 1,000 mg/kg led to larvae reduction (79.6%, 71.3%), respectively. Administration of 50 mg/kg of albendazole resulted in adult and larvae reduction (94.2%, 90.9%). Positive immunostaining of inflammatory cells infiltrating intestinal mucosa and submucosa of all treated groups was detected. Myrrh-treated mice showed the highest iNOS expression followed by albendazole, then thyme. On the other hand, both myrrh and thyme-treated groups showed stronger iNOS expression of inflammatory cells infiltrating and surrounding encapsulated T. spiralis larvae than albendazole treated group. In conclusion, myrrh and thyme extracts are highly effective against both phases of T. spiralis and showed strong iNOS expressions, especially myrrh which could be a promising alternative drug. This experiment provides a basis for further exploration of this plant by isolation and retesting the active principles of both extracts against different stages of T. spiralis.

Polyphenols from aerial parts of Polygonum bellardii and their biological activities.

Abstract Context: Polygonum species have been used in the treatment of several types of inflammatory disorders and cancer. Nevertheless, there are no reports related to the anti-inflammatory and anti-proliferative activities of Polygonum bellardii All. (Polygonaceae). Objective: This study investigated the chemical composition of the methanol extract of P. bellardii. The anti-inflammatory and cytotoxic activities of methanol, n-butanol, ethyl acetate extracts and isolated polyphenols were determined. Materials and methods: The chemical structure of the isolated compounds was elucidated using different spectral techniques. MTT assay was used to evaluate the anti-proliferative activity in HeLa, MCF-7 and HepG-2 cells. Inhibition of 5-lipoxygenase (5-LOX) activity and prostaglandin E2 (PGE2) production in stimulated HepG-2 cells were used to assess the anti-inflammatory activity. Results: The present study resulted in isolation of five compounds (new for the species). They were identified as gallic acid (1), quercetin (2), myricetin (3), quercetin-3-O-β-d-glucopyranoside (5) and myricetin-3-O-α-arabinofuranoside (7). Additionally, a couple of previously isolated compounds such as quercetin-3-O-(5″-acetyl-α-arabinofuranoside) (4) and myricetin-3-O-(5″-acetyl-α-arabinofuranoside) (6) were detected. The n-butanol extract has the highest cytotoxicity in HeLa, MCF-7 and HepG-2 cells, with IC50 values of 15.26, 50.66 and 30.09 µg/ml, respectively. Compound 6 exhibited a marked cytotoxicity in HeLa (IC50 75.04 µg/ml) and HepG-2 (IC50 41.03 µg/ml) cells. Crude extracts and pure compounds inhibited the 5-LOX activity and PGE2 production in a dose-dependent manner (0.1–250 µg/ml). Discussion and conclusion: These results explain the traditional uses of P. bellardii and indicate that polyphenols, despite structural similarity, have different cytotoxic and anti-inflammatory effects.

Xanthone and lignan glycosides from the aerial parts of Polygonum bellardii all growing in Egypt

A new long chain fatty alcohol acetate identified as 17-hydroxypentacosanyl acetate, (1) together with a new xanthone identified as 1,8-Dihydroxy-3,6-dimethoxy-xanthone-5-O-[α-L-rhamnopyranosyl-(1′′→2′)]-β-D-glucopyranoside (3), as well as two new lignans identified as (+)-Lyoniresinol-3a-O-[α-L-rhamnopyranosyl-(1′′′→6′′)]-β-D-glucopyranoside (4) and (+)-Isolariciresinol-3a-O-[α-L-rhamnopyranosyl-(1′′′→2′′)-α-L-rhamnopyranosyl-(1′′′′→6′′)]-β-D-glucopyranoside (5), in addition to β-sitosterol-3-O-acetate (2) were isolated from the methanolic extract of the aerial parts of Polygonum bellardii growing in Egypt. Their structures were elucidated on the basis of different chemical and spectroscopic evidences. The total extract and its fractions, in addition to compounds (3, 4 and 5) showed significant antioxidant potential by DPPH· scavenging activity technique.