Two new cembrane diterpenes, 17-hydroxysarcophytoxide (1) and 7β-acetoxy-8α-hydroxydeepoxysarcoph... more Two new cembrane diterpenes, 17-hydroxysarcophytoxide (1) and 7β-acetoxy-8α-hydroxydeepoxysarcophine (2), together with 7β,8α-dihydroxydeepoxysarcophine (3), sarcophytonin A (4) and (-)-β-elemene (5) have been isolated from the soft coral Sarcophyton sp. 7β-Hydroxy-8α-methoxydeepoxysarcophytoxide (6) and 7α,8β-dihydroxydeepoxysarcophytoxide (7) have been obtained from the soft coral Sarcophyton glaucum. The structures were determined primarily by NMR spectroscopy.
Octopus cyanea.-[isolation of two new indole alkaloids (I) and (II) and confirmation of their str... more Octopus cyanea.-[isolation of two new indole alkaloids (I) and (II) and confirmation of their structure by independent synthesis].-(SHAKER, K. H.; GOEHL, M.;
Endophytes are considered a promising source of new bioactive secondary metabolites and are found... more Endophytes are considered a promising source of new bioactive secondary metabolites and are found in almost all plants. The medicinal plant Bidens bipinnata Lin. (Asteraceae) that is known for its anti-inflammatory, antiseptic and antifungal effects has been chosen for investigation of its endophytes for the search of bioactive secondary metabolites. An endophytic fungus was isolated from the plant and was identified as Khuskia oryzae on the basis of ITS sequence comparison. The ethyl acetate extract of the fungal isolate obtained from the stem parts of the plant exhibits antibacterial activity in agar diffusion assays as well as cytotoxic and antiproliferative effects. Activityguided chromatographic fractionation resulted in the isolation of the active metabolites which were identified by different spectroscopic techniques. A new bioactive oxylipin called 8-oxo-(9E, 11E) octadecadienoic acids and the oxygenated bioactive fatty acid 9-oxo-(10E, 12E) octadecadienoic acids as well as ...
The oxidative modification hypothesis of atherosclerosis predicts that low-density lipoprotein (L... more The oxidative modification hypothesis of atherosclerosis predicts that low-density lipoprotein (LDL) peroxidation is an early event in atherosclerosis. Therefore, inhibition of LDL peroxidation might be an important step in preventing atherogensis. It was hypothesized that honey extracts contain varying amounts of phenolic compounds and that they possess different in vitro antioxidant activity. Honey extracts were analyzed using HPLC and GC/MS to identify and compare phenolic compounds, whereas high-performance liquid chromatography was used for their quantification. The antioxidant activity of Thyme honey and another multifloral honey (MF, from Red Sea area) were evaluated with low density lipoprotein (LDL) peroxidation assay, in different concentrations (100 - 0.1 mg honey/1 ml). The very interesting result that, although the two samples have different chemical composition by GC/MS and HPLC analysis; they exhibited highly significant antioxidant activity within the concentration o...
Antibacterial and cytotoxic activities of Euphorbia balsamifera, fractions and pure compounds wer... more Antibacterial and cytotoxic activities of Euphorbia balsamifera, fractions and pure compounds were evaluated. The cytotoxic assays for HCT116, HePG2 and MCF7 showed a significant IC 50 : 54.7 and 76.2 mg/mL of non-polar fraction ''n-hexane" against HCT116 and HePG2, respectively. Antibacterial results revealed that plant fractions exhibited significant potential against the tested pathogens than the total extract where n-butanol and ethyl acetate fractions showed significant antibacterial activity (P < 0.05) against tested bacterial strains. Isolation and structure determination of compounds from n-hexane and nbutanol fractions were performed. From n-hexane fraction, 29-nor-cycloartanol (1), lanost-8-en-3-ol (2a), cycloartanol (2b) and kampferol-3,4'-dimethyl ether (3) were isolated and structurally identified, along with 24 compounds were tentatively identified by GC-MS. From the polar n-butanol fraction, 4-O-b-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (4), 4-O-a-L-rhamnosyl-(1 ? 6)-b-D-gluco pyranosyl-2-hydroxy-6methoxy-acetophenone (5), quercetin-3-O-glucopyranoside (6) and isoorientin (7) were assigned. Structures of the obtained compounds were determined by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. Except compounds 1 and 5, all reported compounds announced antibacterial efficiency. Compound 2 showed selectively the highest activity against Enterococcus faecalis (22 ± 0.13 mm), meanwhile 4-O-b-D-glucopyranosyl-2-hydroxy-6-methoxyaceto phenone (4) showed broadly the highest antibacterial activity with MIC of 1.15-1.88 mg/mL against the test Gram-positive and Gram-negative bacteria. Cytotoxic assays indicated that kampferol-3,4'dimethyl ether (3) exhibited the highest activity with matching IC 50 values to doxorubicin; 111.46, 42.67 and 44.90 mM against HCT116, HePG2 and MCF7, respectively, however, it is toxic on retina normal cell line RPE1.
The antimicrobial activity of endophytic fungi isolated from Euphorbia milii was evaluated agains... more The antimicrobial activity of endophytic fungi isolated from Euphorbia milii was evaluated against Gram-positive, Gram-negative bacteria, unicellular yeast, and filamentous fungi. Chaetomium ovatoascomatis NRC was identified morphologically and genetically as the most active strain. The total ethyl acetate extract of C. ovatoascomatis NRC demonstrated significant antimicrobial activity against Gram-negative; Escherichia coli, Salmonella enteric, and fungi; Aspergillus niger with MIC of 62.5 ug/ml. Whereas n-hexane fraction demonstrated broader activity against Gram-positive; Bacillus subtilis, Lactobacillus cereus, Gram-negative; Escherichia coli and Salmonella enteric, fungi; Candida albicans and F. solani. LC–MS/MS analysis of ethyl acetate strain extract and GC–MS analysis of the n-hexane fraction were used to identify the metabolites of the strain extract. LC–MS/MS determined three major metabolites with potential antimicrobial activities including grevilline B, aflatoxin G2 and...
T HIS INVESTIGATION deals with assessment of the diversity of 14 populations representing eleven ... more T HIS INVESTIGATION deals with assessment of the diversity of 14 populations representing eleven species of Solanum from southwest Saudi Arabia based on differences in the secondary metabolites by using GC-MS analysis. The analysis was carried out using ethanol extract of the examined Solanum species/populations and 87 different phyto-constituents were detected at six different retention times. The highest M.wt. for the identified compounds was 641 and was recorded in S. villosum at a retention time of 15 min; its formula is C 38 H 35 N 5 O 5 and its decided name is N-benzoyl-9-(2,3,5-triO -benzyl pentofuranosyl)-9H-purin-6-amine. On the other hand, the lowest M.wt. for the identified compounds was 84; its formula is C 6 H 12 and its decided name is 1Hexane and it was recorded in all Solanum species/populations except the two populations of S. incanum, S. coagulans and S. schimperianum at the retention time of 5 min. Based on differences in the phyto-constituents, genetic similarity coefficients were calculated and two distance trees were constructed to illustrate the relatedness of the examined species. The results support a hypothesis that S. villosum and S. nigrum can be regarded as one complex species. The results also revealed that S. coagulans is related to S. macracanthum and S. glabratum and also S. schimperianum is related to S. incanum. The results also revealed that S. torvum, S. sisymbriifolium and S. dulcamara are closely related species. This is generally congruent with the relatedness of the examined specie based on morphological variation and to some extend agree with their systematic treatments.
Cancer is a leading cause of death in several countries. In the search for new anticancer drugs, ... more Cancer is a leading cause of death in several countries. In the search for new anticancer drugs, marine organisms have played an important role in the discovery of lead compounds and the development of new pharmaceuticals for their wide diversity of chemical structures and biological activities. In the present study, the cytotoxicity on colorectal cancer cells HCT116 exerted by marine fungus Aspergillus sp. 2C1-EGY extracts associated with the soft coral Sinularia sp. was investigated; the sub-fractions Fr 2c and Fr 2d had significantly high cytotoxic activity (88 and 85%, respectively). Moreover, the major hexadecanoic, octadecanoic, and octadecenoic acids as well as their methyl esters were isolated. GC/MS analysis revealed the identification of 46 major and minor compounds, from which 19 saturated and unsaturated fatty acids and eight fatty acid esters were identified.
Zeitschrift Fur Naturforschung B a Journal of Chemical Sciences, 2004
The new triterpenoid saponin 3-O-[α-L-rhamnopyranosyl-(1→2)-β -D-xylopyranosyl-(1→2)- β -D-glucur... more The new triterpenoid saponin 3-O-[α-L-rhamnopyranosyl-(1→2)-β -D-xylopyranosyl-(1→2)- β -D-glucuronopyranosyl]-3β ,22α-dihydroxyolean-13-en-11-one has been isolated from Ononis spinosa. The new flavonoid glycoside 3-O-[2-O-(E)-p-coumaroyl-β -D-galactopyranosyl]-7-O-β - D-glucopyranosylkaempferol and the new pterocarpan glucoside 3,4-di-O-β -D-glucopyranosyl-4- hydroxymedicarpin have been obtained from Ononis vaginalis. The structures were determined primarily by NMR spectroscopy. The assignment of NMR signals was performed by means of 1H-1H COSY, ROESY, TOCSY, HMQC HMQC-COSY and HMBC experiments.
One new, 3-O-{[[-α-ʟ-rhamnopyranosyl-(1→2)]-[β-ᴅ-glucopyranosyl-(1→3)]-β-ᴅ-glucopyranosyl-(1→2)]-... more One new, 3-O-{[[-α-ʟ-rhamnopyranosyl-(1→2)]-[β-ᴅ-glucopyranosyl-(1→3)]-β-ᴅ-glucopyranosyl-(1→2)]-β-ᴅ-glucuronopyranosyl}-3β,22α,24-trihydroxyolean-12-ene and two known triterpenoid saponins, 3-O-{[α-ʟ-rhamnopyranosyl-(1→2)]-[β-ᴅ-glucopyranosyl-(1→2)]-β-ᴅ-glucuronopyranosyl}- 3β,22β,24-trihydroxyolean-12-ene (azukisaponin V ) and 3,16-di-O-β-ᴅ-glucopyranosyl- 3β,6α,16β-trihydroxycycloart-24-ene have been isolated from Astragalus trigonus. The structures were determined primarily by NMR spectroscopy. The assignment of NMR signals was performed by means of 1H - 1H COSY, NOESY, ROESY , TOCSY, HMQC and HMBC experiments.
The two new indole alkaloids 2-amino-1,5-dihydro-5-(1H-indol-3-ylmethyl)-4H-imidazol-4-one (1), 2... more The two new indole alkaloids 2-amino-1,5-dihydro-5-(1H-indol-3-ylmethyl)-4H-imidazol-4-one (1), 2-amino-5-[(6-bromo-1H-indol-3-yl)methyl]-3,5-dihydro-3-methyl-4H-imidazol-4-one (2), and auramine (3) have been isolated from the sea anemone Heteractis aurora. Both indole alkaloids were synthesized for the confirmation of the structures. Homarine (4), along with uracil (5), hypoxanthine (6), and inosine (7) have been obtained from Octopus cyanea.
The study aimed to identify the chemical constituents of Leucaeana leucocephala leaves and evalua... more The study aimed to identify the chemical constituents of Leucaeana leucocephala leaves and evaluate the antioxidant and antimicrobial activities of the extract and compounds. An acylated flavanol glycoside, quercetin-3-O-(2''-trans-p-coumaryl)-α-rhamnopyranosyl-(1'''→6'')-β-glucopyranoside (1) in addition to quercetin-3-O-αrhamnopyranosyl-(1'''→2'')-β-glucopyranoside (2), quercetin-7-O-α-rhamnopyranosyl-(1'''→2'')-β-glucopyrano side(3), quercetin-3-O-α-rhamnopyranoside(4), quercetin-3-O-β-glucopyranoside (5), isovitexin(6), vitexin (7) and quercetin (8) were isolated for the first time from the Leucaeana leucocephala. The antioxidant activity of the extract and the isolated compounds 1, 3 & 4 were evaluated by Reducing Power, FRAP, DPPH, Metal chelating and ABTS assays. Compound (3) recorded the highest antioxidant activity in comparison with the extract and other compounds. The extract and compound 1, 2, 3 and 5 were studied for their antimicrobial activity. Both the extract and compound 1 have significant activity against gm-ve bacteria, moderate to gm +ve and Candida and inactive towards fungi. The structures of compounds were elucidated on the basis of spectral analysis. L. leucocephala possess good antioxidant, antibacterial properties and could serve as free radical inhibitors or scavengers, acting possibly as primary antioxidants and have to be investigated for antiinflammatory and anticancer activities.
Acetylcholinesterase (AChE) inhibitors have received considerable attention as alternatives in tr... more Acetylcholinesterase (AChE) inhibitors have received considerable attention as alternatives in treatment of Alzheimer's disease (AD). The damage caused by reactive oxygen species is considered a contributing factor to AD. Three fungi (FC1, FC2 and FC3) were isolated from the soft corals; Sinularia sp. and Lobophyton sp. The antioxidant activities (DPPH and Xanthine Oxidase assays), (AChE) inhibitory activity and antimicrobial activity for twelve different fungal extracts were evaluated. Mycelial ethylacetate extract from the static culture of the fungus FC2 (Emericella unguis 8429) had the highest free radical scavenging activity against DPPH and superoxide anion radicals. Mycelial extract from the shake culture of the isolated three fungi have mild scavenging activity, while their supernatant extracts had no free radical scavenging activity. These data are mentioned for the first time. Screening the AChE inhibitory activity: only FC2 had a significant activity for mycelial extract of the static culture, while mild activity was found in the supernatant extract of the same culture. The three fungal extracts in shake conditions had no AChE inhibitory activity. The supernatant and mycelial extracts from the static culture of the fungus FC2 is highly effective against Pseudomonas aeruginosa, Staph. aureus and Candida albicans. The supernatant extract from the static culture of FC3 is highly effective against Pseudomonas aeruginosa, Staph. aureus and Candida albicans. It could be concluded that, the isolated marine fungus Emericella unguis showed different biological activities as AChE inhibitor (reported for the first time), antioxidant, antimicrobial rather than the unidentified other two fungi (FC1, FC3).
Six compounds were isolated and identified from Bassia muricata and Fagonia indica, two compounds... more Six compounds were isolated and identified from Bassia muricata and Fagonia indica, two compounds are new natural products. Three metabolites, 3,4-dimethoxytoluene (1), 3′-methylquercetin (2) and a new flavonoid glycoside, 3-O-[α-L-arabinopyranosyl-(1→2)-L-α-arabinopyranosyl)]-3′-methylquercetin (3) were isolated from Bassia muricata. From Fagonia indica one flavonoid glycoside; 3-O-[α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranosyl]-kaempferol (4) along with a new triterpenoid saponin; 28-O-[β-D-glucopyranosylester-(1→3)-β-D-glucopyranosyl] oleanolic acid (5) and known quinovic acid-3-O-(α-L-rahmnopyranosyl-)-28-O-β-D-glucopyranosly ester (6) have been isolated. The structure elucidation was performed by nuclear magnetic resonance (NMR) spectroscopic and mass spectrometric methods. Antioxidant activities of pure compounds were measured by DPPH (1,1-diphenyle-2-picryl-hydrazyl) and Xanthine – xanthine oxidase assays.
From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and ide... more From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and identified by different spectral techniques. The isolated compounds included one triterpene 3β-Cycloartenol (1) and three phenolic compounds Chrysin (2), Qurecetin-7-O-β-D-glucoronside (3) and 3-Methyl-Qurecetin-7-O-β-D-glucoronside (4). The structure elucidation of the isolated compounds was done by spectroscopic tools (mass spectrometry and nuclear magnetic resonance NMR spectroscopy). The antioxidant activities were evaluated for three extracts of Euphorbia species (E. schimperiana, E. peplus, E. cuneata) as well as fractions and pure compounds of E. schimperiana by DPPH (1,1-diphenyle-2-picryl-hydrazyl) assay.
International Journal of Pharmaceutical Sciences Review and Research
From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and ide... more From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and identified by different spectral techniques. The isolated compounds included one triterpene 3β-Cycloartenol (1) and three phenolic compounds Chrysin (2), Qurecetin-7-O-β-D-glucoronside (3) and 3-Methyl-Qurecetin-7-O-β-D-glucoronside (4). The structure elucidation of the isolated compounds was done by spectroscopic tools (mass spectrometry and nuclear magnetic resonance NMR spectroscopy). The antioxidant activities were evaluated for three extracts of Euphorbia species (E. schimperiana, E. peplus, E. cuneata) as well as fractions and pure compounds of E. schimperiana by DPPH (1,1-diphenyle-2-picryl-hydrazyl) assay.
Two new cembrane diterpenes, 17-hydroxysarcophytoxide (1) and 7β-acetoxy-8α-hydroxydeepoxysarcoph... more Two new cembrane diterpenes, 17-hydroxysarcophytoxide (1) and 7β-acetoxy-8α-hydroxydeepoxysarcophine (2), together with 7β,8α-dihydroxydeepoxysarcophine (3), sarcophytonin A (4) and (-)-β-elemene (5) have been isolated from the soft coral Sarcophyton sp. 7β-Hydroxy-8α-methoxydeepoxysarcophytoxide (6) and 7α,8β-dihydroxydeepoxysarcophytoxide (7) have been obtained from the soft coral Sarcophyton glaucum. The structures were determined primarily by NMR spectroscopy.
Octopus cyanea.-[isolation of two new indole alkaloids (I) and (II) and confirmation of their str... more Octopus cyanea.-[isolation of two new indole alkaloids (I) and (II) and confirmation of their structure by independent synthesis].-(SHAKER, K. H.; GOEHL, M.;
Endophytes are considered a promising source of new bioactive secondary metabolites and are found... more Endophytes are considered a promising source of new bioactive secondary metabolites and are found in almost all plants. The medicinal plant Bidens bipinnata Lin. (Asteraceae) that is known for its anti-inflammatory, antiseptic and antifungal effects has been chosen for investigation of its endophytes for the search of bioactive secondary metabolites. An endophytic fungus was isolated from the plant and was identified as Khuskia oryzae on the basis of ITS sequence comparison. The ethyl acetate extract of the fungal isolate obtained from the stem parts of the plant exhibits antibacterial activity in agar diffusion assays as well as cytotoxic and antiproliferative effects. Activityguided chromatographic fractionation resulted in the isolation of the active metabolites which were identified by different spectroscopic techniques. A new bioactive oxylipin called 8-oxo-(9E, 11E) octadecadienoic acids and the oxygenated bioactive fatty acid 9-oxo-(10E, 12E) octadecadienoic acids as well as ...
The oxidative modification hypothesis of atherosclerosis predicts that low-density lipoprotein (L... more The oxidative modification hypothesis of atherosclerosis predicts that low-density lipoprotein (LDL) peroxidation is an early event in atherosclerosis. Therefore, inhibition of LDL peroxidation might be an important step in preventing atherogensis. It was hypothesized that honey extracts contain varying amounts of phenolic compounds and that they possess different in vitro antioxidant activity. Honey extracts were analyzed using HPLC and GC/MS to identify and compare phenolic compounds, whereas high-performance liquid chromatography was used for their quantification. The antioxidant activity of Thyme honey and another multifloral honey (MF, from Red Sea area) were evaluated with low density lipoprotein (LDL) peroxidation assay, in different concentrations (100 - 0.1 mg honey/1 ml). The very interesting result that, although the two samples have different chemical composition by GC/MS and HPLC analysis; they exhibited highly significant antioxidant activity within the concentration o...
Antibacterial and cytotoxic activities of Euphorbia balsamifera, fractions and pure compounds wer... more Antibacterial and cytotoxic activities of Euphorbia balsamifera, fractions and pure compounds were evaluated. The cytotoxic assays for HCT116, HePG2 and MCF7 showed a significant IC 50 : 54.7 and 76.2 mg/mL of non-polar fraction ''n-hexane" against HCT116 and HePG2, respectively. Antibacterial results revealed that plant fractions exhibited significant potential against the tested pathogens than the total extract where n-butanol and ethyl acetate fractions showed significant antibacterial activity (P < 0.05) against tested bacterial strains. Isolation and structure determination of compounds from n-hexane and nbutanol fractions were performed. From n-hexane fraction, 29-nor-cycloartanol (1), lanost-8-en-3-ol (2a), cycloartanol (2b) and kampferol-3,4'-dimethyl ether (3) were isolated and structurally identified, along with 24 compounds were tentatively identified by GC-MS. From the polar n-butanol fraction, 4-O-b-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (4), 4-O-a-L-rhamnosyl-(1 ? 6)-b-D-gluco pyranosyl-2-hydroxy-6methoxy-acetophenone (5), quercetin-3-O-glucopyranoside (6) and isoorientin (7) were assigned. Structures of the obtained compounds were determined by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. Except compounds 1 and 5, all reported compounds announced antibacterial efficiency. Compound 2 showed selectively the highest activity against Enterococcus faecalis (22 ± 0.13 mm), meanwhile 4-O-b-D-glucopyranosyl-2-hydroxy-6-methoxyaceto phenone (4) showed broadly the highest antibacterial activity with MIC of 1.15-1.88 mg/mL against the test Gram-positive and Gram-negative bacteria. Cytotoxic assays indicated that kampferol-3,4'dimethyl ether (3) exhibited the highest activity with matching IC 50 values to doxorubicin; 111.46, 42.67 and 44.90 mM against HCT116, HePG2 and MCF7, respectively, however, it is toxic on retina normal cell line RPE1.
The antimicrobial activity of endophytic fungi isolated from Euphorbia milii was evaluated agains... more The antimicrobial activity of endophytic fungi isolated from Euphorbia milii was evaluated against Gram-positive, Gram-negative bacteria, unicellular yeast, and filamentous fungi. Chaetomium ovatoascomatis NRC was identified morphologically and genetically as the most active strain. The total ethyl acetate extract of C. ovatoascomatis NRC demonstrated significant antimicrobial activity against Gram-negative; Escherichia coli, Salmonella enteric, and fungi; Aspergillus niger with MIC of 62.5 ug/ml. Whereas n-hexane fraction demonstrated broader activity against Gram-positive; Bacillus subtilis, Lactobacillus cereus, Gram-negative; Escherichia coli and Salmonella enteric, fungi; Candida albicans and F. solani. LC–MS/MS analysis of ethyl acetate strain extract and GC–MS analysis of the n-hexane fraction were used to identify the metabolites of the strain extract. LC–MS/MS determined three major metabolites with potential antimicrobial activities including grevilline B, aflatoxin G2 and...
T HIS INVESTIGATION deals with assessment of the diversity of 14 populations representing eleven ... more T HIS INVESTIGATION deals with assessment of the diversity of 14 populations representing eleven species of Solanum from southwest Saudi Arabia based on differences in the secondary metabolites by using GC-MS analysis. The analysis was carried out using ethanol extract of the examined Solanum species/populations and 87 different phyto-constituents were detected at six different retention times. The highest M.wt. for the identified compounds was 641 and was recorded in S. villosum at a retention time of 15 min; its formula is C 38 H 35 N 5 O 5 and its decided name is N-benzoyl-9-(2,3,5-triO -benzyl pentofuranosyl)-9H-purin-6-amine. On the other hand, the lowest M.wt. for the identified compounds was 84; its formula is C 6 H 12 and its decided name is 1Hexane and it was recorded in all Solanum species/populations except the two populations of S. incanum, S. coagulans and S. schimperianum at the retention time of 5 min. Based on differences in the phyto-constituents, genetic similarity coefficients were calculated and two distance trees were constructed to illustrate the relatedness of the examined species. The results support a hypothesis that S. villosum and S. nigrum can be regarded as one complex species. The results also revealed that S. coagulans is related to S. macracanthum and S. glabratum and also S. schimperianum is related to S. incanum. The results also revealed that S. torvum, S. sisymbriifolium and S. dulcamara are closely related species. This is generally congruent with the relatedness of the examined specie based on morphological variation and to some extend agree with their systematic treatments.
Cancer is a leading cause of death in several countries. In the search for new anticancer drugs, ... more Cancer is a leading cause of death in several countries. In the search for new anticancer drugs, marine organisms have played an important role in the discovery of lead compounds and the development of new pharmaceuticals for their wide diversity of chemical structures and biological activities. In the present study, the cytotoxicity on colorectal cancer cells HCT116 exerted by marine fungus Aspergillus sp. 2C1-EGY extracts associated with the soft coral Sinularia sp. was investigated; the sub-fractions Fr 2c and Fr 2d had significantly high cytotoxic activity (88 and 85%, respectively). Moreover, the major hexadecanoic, octadecanoic, and octadecenoic acids as well as their methyl esters were isolated. GC/MS analysis revealed the identification of 46 major and minor compounds, from which 19 saturated and unsaturated fatty acids and eight fatty acid esters were identified.
Zeitschrift Fur Naturforschung B a Journal of Chemical Sciences, 2004
The new triterpenoid saponin 3-O-[α-L-rhamnopyranosyl-(1→2)-β -D-xylopyranosyl-(1→2)- β -D-glucur... more The new triterpenoid saponin 3-O-[α-L-rhamnopyranosyl-(1→2)-β -D-xylopyranosyl-(1→2)- β -D-glucuronopyranosyl]-3β ,22α-dihydroxyolean-13-en-11-one has been isolated from Ononis spinosa. The new flavonoid glycoside 3-O-[2-O-(E)-p-coumaroyl-β -D-galactopyranosyl]-7-O-β - D-glucopyranosylkaempferol and the new pterocarpan glucoside 3,4-di-O-β -D-glucopyranosyl-4- hydroxymedicarpin have been obtained from Ononis vaginalis. The structures were determined primarily by NMR spectroscopy. The assignment of NMR signals was performed by means of 1H-1H COSY, ROESY, TOCSY, HMQC HMQC-COSY and HMBC experiments.
One new, 3-O-{[[-α-ʟ-rhamnopyranosyl-(1→2)]-[β-ᴅ-glucopyranosyl-(1→3)]-β-ᴅ-glucopyranosyl-(1→2)]-... more One new, 3-O-{[[-α-ʟ-rhamnopyranosyl-(1→2)]-[β-ᴅ-glucopyranosyl-(1→3)]-β-ᴅ-glucopyranosyl-(1→2)]-β-ᴅ-glucuronopyranosyl}-3β,22α,24-trihydroxyolean-12-ene and two known triterpenoid saponins, 3-O-{[α-ʟ-rhamnopyranosyl-(1→2)]-[β-ᴅ-glucopyranosyl-(1→2)]-β-ᴅ-glucuronopyranosyl}- 3β,22β,24-trihydroxyolean-12-ene (azukisaponin V ) and 3,16-di-O-β-ᴅ-glucopyranosyl- 3β,6α,16β-trihydroxycycloart-24-ene have been isolated from Astragalus trigonus. The structures were determined primarily by NMR spectroscopy. The assignment of NMR signals was performed by means of 1H - 1H COSY, NOESY, ROESY , TOCSY, HMQC and HMBC experiments.
The two new indole alkaloids 2-amino-1,5-dihydro-5-(1H-indol-3-ylmethyl)-4H-imidazol-4-one (1), 2... more The two new indole alkaloids 2-amino-1,5-dihydro-5-(1H-indol-3-ylmethyl)-4H-imidazol-4-one (1), 2-amino-5-[(6-bromo-1H-indol-3-yl)methyl]-3,5-dihydro-3-methyl-4H-imidazol-4-one (2), and auramine (3) have been isolated from the sea anemone Heteractis aurora. Both indole alkaloids were synthesized for the confirmation of the structures. Homarine (4), along with uracil (5), hypoxanthine (6), and inosine (7) have been obtained from Octopus cyanea.
The study aimed to identify the chemical constituents of Leucaeana leucocephala leaves and evalua... more The study aimed to identify the chemical constituents of Leucaeana leucocephala leaves and evaluate the antioxidant and antimicrobial activities of the extract and compounds. An acylated flavanol glycoside, quercetin-3-O-(2''-trans-p-coumaryl)-α-rhamnopyranosyl-(1'''→6'')-β-glucopyranoside (1) in addition to quercetin-3-O-αrhamnopyranosyl-(1'''→2'')-β-glucopyranoside (2), quercetin-7-O-α-rhamnopyranosyl-(1'''→2'')-β-glucopyrano side(3), quercetin-3-O-α-rhamnopyranoside(4), quercetin-3-O-β-glucopyranoside (5), isovitexin(6), vitexin (7) and quercetin (8) were isolated for the first time from the Leucaeana leucocephala. The antioxidant activity of the extract and the isolated compounds 1, 3 & 4 were evaluated by Reducing Power, FRAP, DPPH, Metal chelating and ABTS assays. Compound (3) recorded the highest antioxidant activity in comparison with the extract and other compounds. The extract and compound 1, 2, 3 and 5 were studied for their antimicrobial activity. Both the extract and compound 1 have significant activity against gm-ve bacteria, moderate to gm +ve and Candida and inactive towards fungi. The structures of compounds were elucidated on the basis of spectral analysis. L. leucocephala possess good antioxidant, antibacterial properties and could serve as free radical inhibitors or scavengers, acting possibly as primary antioxidants and have to be investigated for antiinflammatory and anticancer activities.
Acetylcholinesterase (AChE) inhibitors have received considerable attention as alternatives in tr... more Acetylcholinesterase (AChE) inhibitors have received considerable attention as alternatives in treatment of Alzheimer's disease (AD). The damage caused by reactive oxygen species is considered a contributing factor to AD. Three fungi (FC1, FC2 and FC3) were isolated from the soft corals; Sinularia sp. and Lobophyton sp. The antioxidant activities (DPPH and Xanthine Oxidase assays), (AChE) inhibitory activity and antimicrobial activity for twelve different fungal extracts were evaluated. Mycelial ethylacetate extract from the static culture of the fungus FC2 (Emericella unguis 8429) had the highest free radical scavenging activity against DPPH and superoxide anion radicals. Mycelial extract from the shake culture of the isolated three fungi have mild scavenging activity, while their supernatant extracts had no free radical scavenging activity. These data are mentioned for the first time. Screening the AChE inhibitory activity: only FC2 had a significant activity for mycelial extract of the static culture, while mild activity was found in the supernatant extract of the same culture. The three fungal extracts in shake conditions had no AChE inhibitory activity. The supernatant and mycelial extracts from the static culture of the fungus FC2 is highly effective against Pseudomonas aeruginosa, Staph. aureus and Candida albicans. The supernatant extract from the static culture of FC3 is highly effective against Pseudomonas aeruginosa, Staph. aureus and Candida albicans. It could be concluded that, the isolated marine fungus Emericella unguis showed different biological activities as AChE inhibitor (reported for the first time), antioxidant, antimicrobial rather than the unidentified other two fungi (FC1, FC3).
Six compounds were isolated and identified from Bassia muricata and Fagonia indica, two compounds... more Six compounds were isolated and identified from Bassia muricata and Fagonia indica, two compounds are new natural products. Three metabolites, 3,4-dimethoxytoluene (1), 3′-methylquercetin (2) and a new flavonoid glycoside, 3-O-[α-L-arabinopyranosyl-(1→2)-L-α-arabinopyranosyl)]-3′-methylquercetin (3) were isolated from Bassia muricata. From Fagonia indica one flavonoid glycoside; 3-O-[α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranosyl]-kaempferol (4) along with a new triterpenoid saponin; 28-O-[β-D-glucopyranosylester-(1→3)-β-D-glucopyranosyl] oleanolic acid (5) and known quinovic acid-3-O-(α-L-rahmnopyranosyl-)-28-O-β-D-glucopyranosly ester (6) have been isolated. The structure elucidation was performed by nuclear magnetic resonance (NMR) spectroscopic and mass spectrometric methods. Antioxidant activities of pure compounds were measured by DPPH (1,1-diphenyle-2-picryl-hydrazyl) and Xanthine – xanthine oxidase assays.
From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and ide... more From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and identified by different spectral techniques. The isolated compounds included one triterpene 3β-Cycloartenol (1) and three phenolic compounds Chrysin (2), Qurecetin-7-O-β-D-glucoronside (3) and 3-Methyl-Qurecetin-7-O-β-D-glucoronside (4). The structure elucidation of the isolated compounds was done by spectroscopic tools (mass spectrometry and nuclear magnetic resonance NMR spectroscopy). The antioxidant activities were evaluated for three extracts of Euphorbia species (E. schimperiana, E. peplus, E. cuneata) as well as fractions and pure compounds of E. schimperiana by DPPH (1,1-diphenyle-2-picryl-hydrazyl) assay.
International Journal of Pharmaceutical Sciences Review and Research
From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and ide... more From the whole part of Euphorbia schimperiana scheele, four compounds were isolated (1-4) and identified by different spectral techniques. The isolated compounds included one triterpene 3β-Cycloartenol (1) and three phenolic compounds Chrysin (2), Qurecetin-7-O-β-D-glucoronside (3) and 3-Methyl-Qurecetin-7-O-β-D-glucoronside (4). The structure elucidation of the isolated compounds was done by spectroscopic tools (mass spectrometry and nuclear magnetic resonance NMR spectroscopy). The antioxidant activities were evaluated for three extracts of Euphorbia species (E. schimperiana, E. peplus, E. cuneata) as well as fractions and pure compounds of E. schimperiana by DPPH (1,1-diphenyle-2-picryl-hydrazyl) assay.
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