Mohamed M I Mohamed | Stockton University (original) (raw)
Books by Mohamed M I Mohamed
Papers by Mohamed M I Mohamed
Organic & biomolecular chemistry, Jan 10, 2015
Novel, cyclic peptidomimetics were synthesized by facile acylation reactions using benzotriazole ... more Novel, cyclic peptidomimetics were synthesized by facile acylation reactions using benzotriazole chemistry. Microbiological testing of the synthesized compounds revealed an exceptionally high activity against Candida albicans with a minimum inhibitory concentration (MIC) two orders of magnitude lower than the MIC of the antifungal reference drug amphotericin B. A strikingly high activity was also observed against three Gram-negative bacterial strains (Pseudomonas aeruginosa, Klebsiella pneumoniae and Proteus vulgaris), two of which are known human pathogens. Thus the discovered chemotype is a potential polypharmacological agent. The toxicity against mammalian tumor cells was found to be low, as demonstrated in five different human cell lines (HeLa, cervical; PC-3, prostate; MCF-7, breast; HepG2, liver; and HCT-116, colon). The internal consistency of the experimental data was studied using 3D-pharmacophore and 2D-QSAR.
Saudi Journal of Biological Sciences, 2015
Journal of neurophysiology, Jan 24, 2015
Functional neuroplasticity in response to stimulation and motor training is a well-established ph... more Functional neuroplasticity in response to stimulation and motor training is a well-established phenomenon. Transcutaneous stimulation of the spine is used mostly to alleviate pain, but it may also induce functional neuroplasticity, because the spinal cord serves as an integration center for descending and ascending neuronal signals. In this work, we examined whether long-lasting noninvasive cathodal and anodal transpinal constant current stimulation (c-tsCCS, a-tsCCS) over the thoracolumbar enlargement can induce cortical, corticospinal, and spinal neuroplasticity. Twelve healthy human subjects, blind to the stimulation protocol, were randomly assigned to 40 min of c-tsCCS or a-tsCCS. Before and after transpinal stimulation, we established the afferent-mediated motor evoked potential (MEP) facilitation and the subthreshold TMS-mediated flexor reflex facilitation. Recruitment input-output curves of MEPs and transpinal evoked potentials (TEPs), and post-activation depression of the so...
Journal of Ophthalmic Inflammation and Infection, 2015
Translational Vision Science & Technology, 2015
To determine the efficacy and safety of repeated intravitreal and subconjunctival administrations... more To determine the efficacy and safety of repeated intravitreal and subconjunctival administrations of sirolimus in patients with noninfectious uveitis at 1 year in the Sirolimus as a Therapeutic Approach UVEitis (SAVE) Study. Open-label, prospective, and randomized interventional clinical trial in which 30 patients with noninfectious intermediate, posterior, or panuveitis were randomized 1:1 to receive sirolimus 352-μg intravitreal or 1320-μg subconjunctival. Sirolimus was administered at days 0, 60, and 120. At month 6, all subjects were allowed to receive sirolimus at intervals greater than or equal to 2 months and until month 12. Changes in vitreous haze (VH), visual acuity (VA), and retinal thickness at month 12 were compared with baseline. Of patients with active uveitis at baseline (n = 20), 70% showed greater than or equal to 2 steps reduction of VH at month 12 (P < 0.05), 88% (n = 7) of patients with inactive uveitis at baseline showed either no change or reduction of VH to no haze, 36% (n = 10) of all patients (n = 28) gained greater than or equal to one line of VA, 21% (n = 6) lost greater than or equal to 1 line, and 43% (n = 12) showed no change. At the end of 1 year, no statistical differences in efficacy were found between intravitreal and subconjunctival groups. No serious adverse events were determined to be secondary to sirolimus. Repeated subconjunctival/intravitreal injections of sirolimus appear to be tolerated by patients with noninfectious uveitis over 12 months. Results from the index study suggest that sirolimus may provide benefits to patients with uveitis. Both intravitreal and subconjunctival routes demonstrate similar bioactivity/efficacy. The intravitreal route, however, was better tolerated. The SAVE Study illustrates for the first time the application of local formulations of sirolimus in non-infectious intermediate, posterior, and pan-uveitis. Subconjunctival/Intravitreal sirolimus may help to control inflammation while offering better tolerability/safety profiles than systemic therapies, including immunosuppressants and corticosteroids.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, Jan 14, 2015
The molecular complex between 1-(2-methoxyphenyl)-1H-imidazole-2(3H)-thione (Hmim(OMe)) and iodin... more The molecular complex between 1-(2-methoxyphenyl)-1H-imidazole-2(3H)-thione (Hmim(OMe)) and iodine (I2) was investigated. Single crystal of [(Hmim(OMe))I2] adduct was grown by slow evaporation technique from chloroform at room temperature. Spectroscopic techniques such as FT-IR and Raman techniques, as well as elemental and thermal analysis were used to characterize the complex. The crystal structure shows that the formed adduct stabilized by two noncovalent interactions, namely, hydrogen bond (HB) and halogen bond (XB). Orthogonal HB/XB associated with iodine atom (I) was observed and fully characterized. The ability of iodine to behave as hydrogen bond acceptor and halogen bond donor was held responsible for the orthogonal HB/XB presence. In addition, the structure of Hmim(OMe)I2 was investigated theoretically using MP2/aug-cc-pVDZ level of theory. Natural bond orbital analysis (NBO) was used to investigate the molecular orbitals interactions and orbitals stabilization energies.
Quantitative imaging in medicine and surgery, 2015
To assess oxygen saturation (StO2) in retinal vessels of normal subjects and diabetic patients wi... more To assess oxygen saturation (StO2) in retinal vessels of normal subjects and diabetic patients with and without retinopathy using the modified version of the Flow Oximetry System (FOS) and a novel assessment software. The FOS and novel assessment software were used to determine StO2 levels in arteries and veins located between 1 and 2 mm from the margin of the optic disc and in the macular area. Eighteen normal subjects, 15 diabetics without diabetic retinopathy (DM no DR), and 11 with non-proliferative diabetic retinopathy (NPDR) were included in final analysis. The mean [± standard deviation (SD)] StO2 in retinal arteries was 96.9%±3.8% in normal subjects; 97.4%±3.7% in DM no DR; and 98.4%±2.0% in NPDR. The mean venous StO2 was 57.5%±6.8% in normal subjects; 57.4%±7.5% in DM no DR; and 51.8%±6.8% in NPDR. The mean arterial and venous StO2 across the three groups were not statistically different (P=0.498 and P=0.071, respectively). The arterio-venous differences between the three s...
Radiation Physics and Chemistry, 2007
Graft copolymer networks of poly(methacrylic acid-g-polyamidoamine dendrimer) with different load... more Graft copolymer networks of poly(methacrylic acid-g-polyamidoamine dendrimer) with different loads of nickel salt were synthesized by gamma radiation-induced copolymerization of polyamidoamine dendrimer and methacrylic acid (MAA). Nickel release and metal adsorption from the polymeric systems, and their thermal stability were analyzed. A high percentage of the nickel loaded was released, although strong interactions between the polymeric matrices and the nickel
Journal of natural products, 2009
One known and three new potent, selective, and nontoxic anti-MRSA metabolites, kaempferol…
BMC pharmacology & toxicology, Jan 14, 2013
This study was designed to assess the safety, tolerability, and efficacy of intravenous infusion ... more This study was designed to assess the safety, tolerability, and efficacy of intravenous infusion of CA4P in patients with neovascular age-related macular degeneration (AMD). Prospective, interventional, dose-escalation clinical trial. Eight patients with neovascular AMD refractory to at least 2 sessions of photodynamic therapy received CA4P at a dose of 27 or 36 mg/m2 as weekly intravenous infusion for 4 consecutive weeks. Safety was monitored by vital signs, ocular and physical examinations, electrocardiogram, routine laboratory tests, and collection of adverse events. Efficacy was assessed using retinal fluorescein angiography, optical coherence tomography, and best corrected visual acuity (BCVA). The most common adverse events were elevated blood pressure (46.7%), QTc prolongation (23.3%), elevated temperature (13.3%), and headache (10%), followed by nausea and eye injection (6.7%). There were no adverse events that were considered severe in intensity and none resulted in discont...
Translational vision science & technology, 2014
To compare the retinal sensitivity measurements obtained with two microperimeters, the Micro-Peri... more To compare the retinal sensitivity measurements obtained with two microperimeters, the Micro-Perimeter 1 (MP-1) and the Optos optical coherence tomography (OCT)/scanning laser ophthalmoscope (SLO) in subjects with and without maculopathies. Forty-five eyes with no known ocular disease and 47 eyes with maculopathies were examined using both microperimeters. A contrast-adjusted scale was applied to resolve the different stimuli and background luminance existing between the two devices. There was a strong ceiling effect with the MP-1 in the healthy group, with 90.1% (1136 of 1260) test points clustered at 20 dB. The mean sensitivity for the corresponding points in the OCT/SLO was 25.8 ± 1.9 dB. A floor effect was also observed with the OCT/SLO in the maculopathy group with 9.7% (128 of 1316) points clustered at 9-dB values. The corresponding mean sensitivity in the MP-1 was 1.7 ± 3.9 dB. A regression equation between the two microperimeters was established in the common 10 to19 dB inte...
Crosswell seismic surveys were conducted at two fields in northern Michigan. One of these, Spring... more Crosswell seismic surveys were conducted at two fields in northern Michigan. One of these, Springdale, included two monitor wells that are located external to the reef, and the other, Coldspring, employed two production wells within the reef. The Springdale wells ...
Abu Dhabi International Petroleum Exhibition and Conference, 2010
Tetrahedron Letters, 2008
Proceedings of the National Academy of Sciences, 2013
X-ray computed tomography is a powerful non-invasive imaging technique for viewing an object'... more X-ray computed tomography is a powerful non-invasive imaging technique for viewing an object's inner structures in two-dimensional cross-section images without the need to physically section it. The invention of CT techniques revolutionised the field of medical diagnostic imaging because it provided more detailed and useful information than any previous non-invasive imaging techniques. The method is increasingly being used in industry, aerospace, geosciences and archaeology. This paper describes the development of an X-ray computed tomography system for imaging of industrial materials. The theoretical aspects of CT scanner, the system configurations and the adopted algorithm for image reconstruction are discussed. The penetrating rays from a 160 kV industrial X-ray machine were used to investigate structures that manifest in a manufactured component or product. Some results were presented in this paper.
Journal of Natural Products, 2014
Two new diterpene glycosides in addition to five known glycosides have been isolated from a comme... more Two new diterpene glycosides in addition to five known glycosides have been isolated from a commercial extract of the leaves of Stevia rebaudiana. Compound 1 (rebaudioside KA) was shown to be 13-[(O-β-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid 2-O-β-d-glucopyranosyl-β-d-glucopyranosyl ester and compound 2, 12-α-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester. Five additional known compounds were identified, rebaudioside E, rebaudioside M, rebaudioside N, rebaudioside O, and stevioside, respectively. Enzymatic hydrolysis of stevioside afforded the known ent-kaurane aglycone 13-hydroxy-ent-kaur-16-en-19-oic acid (steviol) (3). The isolated metabolite 1 possesses the ent-kaurane aglycone steviol (3), while compound 2 represents the first example of the isomeric diterpene 12-α-hydroxy-ent-kaur-16-en-19-oic acid existing as a glycoside in S. rebaudiana. The structures of the isolated metabolites 1 and 2 were determined based on comprehensive 1D- and 2D-NMR (COSY, HSQC, and HMBC) studies. A high-quality crystal of compound 3 has formed, which allowed the acquisition of X-ray diffraction data that confirmed its structure. The structural similarities between the new metabolites and the commercially available stevioside sweeteners suggest the newly isolated metabolites should be examined for their organoleptic properties. Accordingly rebaudiosides E, M, N, O, and KA have been isolated in greater than gram quantities.
Organic & biomolecular chemistry, Jan 10, 2015
Novel, cyclic peptidomimetics were synthesized by facile acylation reactions using benzotriazole ... more Novel, cyclic peptidomimetics were synthesized by facile acylation reactions using benzotriazole chemistry. Microbiological testing of the synthesized compounds revealed an exceptionally high activity against Candida albicans with a minimum inhibitory concentration (MIC) two orders of magnitude lower than the MIC of the antifungal reference drug amphotericin B. A strikingly high activity was also observed against three Gram-negative bacterial strains (Pseudomonas aeruginosa, Klebsiella pneumoniae and Proteus vulgaris), two of which are known human pathogens. Thus the discovered chemotype is a potential polypharmacological agent. The toxicity against mammalian tumor cells was found to be low, as demonstrated in five different human cell lines (HeLa, cervical; PC-3, prostate; MCF-7, breast; HepG2, liver; and HCT-116, colon). The internal consistency of the experimental data was studied using 3D-pharmacophore and 2D-QSAR.
Saudi Journal of Biological Sciences, 2015
Journal of neurophysiology, Jan 24, 2015
Functional neuroplasticity in response to stimulation and motor training is a well-established ph... more Functional neuroplasticity in response to stimulation and motor training is a well-established phenomenon. Transcutaneous stimulation of the spine is used mostly to alleviate pain, but it may also induce functional neuroplasticity, because the spinal cord serves as an integration center for descending and ascending neuronal signals. In this work, we examined whether long-lasting noninvasive cathodal and anodal transpinal constant current stimulation (c-tsCCS, a-tsCCS) over the thoracolumbar enlargement can induce cortical, corticospinal, and spinal neuroplasticity. Twelve healthy human subjects, blind to the stimulation protocol, were randomly assigned to 40 min of c-tsCCS or a-tsCCS. Before and after transpinal stimulation, we established the afferent-mediated motor evoked potential (MEP) facilitation and the subthreshold TMS-mediated flexor reflex facilitation. Recruitment input-output curves of MEPs and transpinal evoked potentials (TEPs), and post-activation depression of the so...
Journal of Ophthalmic Inflammation and Infection, 2015
Translational Vision Science & Technology, 2015
To determine the efficacy and safety of repeated intravitreal and subconjunctival administrations... more To determine the efficacy and safety of repeated intravitreal and subconjunctival administrations of sirolimus in patients with noninfectious uveitis at 1 year in the Sirolimus as a Therapeutic Approach UVEitis (SAVE) Study. Open-label, prospective, and randomized interventional clinical trial in which 30 patients with noninfectious intermediate, posterior, or panuveitis were randomized 1:1 to receive sirolimus 352-μg intravitreal or 1320-μg subconjunctival. Sirolimus was administered at days 0, 60, and 120. At month 6, all subjects were allowed to receive sirolimus at intervals greater than or equal to 2 months and until month 12. Changes in vitreous haze (VH), visual acuity (VA), and retinal thickness at month 12 were compared with baseline. Of patients with active uveitis at baseline (n = 20), 70% showed greater than or equal to 2 steps reduction of VH at month 12 (P < 0.05), 88% (n = 7) of patients with inactive uveitis at baseline showed either no change or reduction of VH to no haze, 36% (n = 10) of all patients (n = 28) gained greater than or equal to one line of VA, 21% (n = 6) lost greater than or equal to 1 line, and 43% (n = 12) showed no change. At the end of 1 year, no statistical differences in efficacy were found between intravitreal and subconjunctival groups. No serious adverse events were determined to be secondary to sirolimus. Repeated subconjunctival/intravitreal injections of sirolimus appear to be tolerated by patients with noninfectious uveitis over 12 months. Results from the index study suggest that sirolimus may provide benefits to patients with uveitis. Both intravitreal and subconjunctival routes demonstrate similar bioactivity/efficacy. The intravitreal route, however, was better tolerated. The SAVE Study illustrates for the first time the application of local formulations of sirolimus in non-infectious intermediate, posterior, and pan-uveitis. Subconjunctival/Intravitreal sirolimus may help to control inflammation while offering better tolerability/safety profiles than systemic therapies, including immunosuppressants and corticosteroids.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, Jan 14, 2015
The molecular complex between 1-(2-methoxyphenyl)-1H-imidazole-2(3H)-thione (Hmim(OMe)) and iodin... more The molecular complex between 1-(2-methoxyphenyl)-1H-imidazole-2(3H)-thione (Hmim(OMe)) and iodine (I2) was investigated. Single crystal of [(Hmim(OMe))I2] adduct was grown by slow evaporation technique from chloroform at room temperature. Spectroscopic techniques such as FT-IR and Raman techniques, as well as elemental and thermal analysis were used to characterize the complex. The crystal structure shows that the formed adduct stabilized by two noncovalent interactions, namely, hydrogen bond (HB) and halogen bond (XB). Orthogonal HB/XB associated with iodine atom (I) was observed and fully characterized. The ability of iodine to behave as hydrogen bond acceptor and halogen bond donor was held responsible for the orthogonal HB/XB presence. In addition, the structure of Hmim(OMe)I2 was investigated theoretically using MP2/aug-cc-pVDZ level of theory. Natural bond orbital analysis (NBO) was used to investigate the molecular orbitals interactions and orbitals stabilization energies.
Quantitative imaging in medicine and surgery, 2015
To assess oxygen saturation (StO2) in retinal vessels of normal subjects and diabetic patients wi... more To assess oxygen saturation (StO2) in retinal vessels of normal subjects and diabetic patients with and without retinopathy using the modified version of the Flow Oximetry System (FOS) and a novel assessment software. The FOS and novel assessment software were used to determine StO2 levels in arteries and veins located between 1 and 2 mm from the margin of the optic disc and in the macular area. Eighteen normal subjects, 15 diabetics without diabetic retinopathy (DM no DR), and 11 with non-proliferative diabetic retinopathy (NPDR) were included in final analysis. The mean [± standard deviation (SD)] StO2 in retinal arteries was 96.9%±3.8% in normal subjects; 97.4%±3.7% in DM no DR; and 98.4%±2.0% in NPDR. The mean venous StO2 was 57.5%±6.8% in normal subjects; 57.4%±7.5% in DM no DR; and 51.8%±6.8% in NPDR. The mean arterial and venous StO2 across the three groups were not statistically different (P=0.498 and P=0.071, respectively). The arterio-venous differences between the three s...
Radiation Physics and Chemistry, 2007
Graft copolymer networks of poly(methacrylic acid-g-polyamidoamine dendrimer) with different load... more Graft copolymer networks of poly(methacrylic acid-g-polyamidoamine dendrimer) with different loads of nickel salt were synthesized by gamma radiation-induced copolymerization of polyamidoamine dendrimer and methacrylic acid (MAA). Nickel release and metal adsorption from the polymeric systems, and their thermal stability were analyzed. A high percentage of the nickel loaded was released, although strong interactions between the polymeric matrices and the nickel
Journal of natural products, 2009
One known and three new potent, selective, and nontoxic anti-MRSA metabolites, kaempferol…
BMC pharmacology & toxicology, Jan 14, 2013
This study was designed to assess the safety, tolerability, and efficacy of intravenous infusion ... more This study was designed to assess the safety, tolerability, and efficacy of intravenous infusion of CA4P in patients with neovascular age-related macular degeneration (AMD). Prospective, interventional, dose-escalation clinical trial. Eight patients with neovascular AMD refractory to at least 2 sessions of photodynamic therapy received CA4P at a dose of 27 or 36 mg/m2 as weekly intravenous infusion for 4 consecutive weeks. Safety was monitored by vital signs, ocular and physical examinations, electrocardiogram, routine laboratory tests, and collection of adverse events. Efficacy was assessed using retinal fluorescein angiography, optical coherence tomography, and best corrected visual acuity (BCVA). The most common adverse events were elevated blood pressure (46.7%), QTc prolongation (23.3%), elevated temperature (13.3%), and headache (10%), followed by nausea and eye injection (6.7%). There were no adverse events that were considered severe in intensity and none resulted in discont...
Translational vision science & technology, 2014
To compare the retinal sensitivity measurements obtained with two microperimeters, the Micro-Peri... more To compare the retinal sensitivity measurements obtained with two microperimeters, the Micro-Perimeter 1 (MP-1) and the Optos optical coherence tomography (OCT)/scanning laser ophthalmoscope (SLO) in subjects with and without maculopathies. Forty-five eyes with no known ocular disease and 47 eyes with maculopathies were examined using both microperimeters. A contrast-adjusted scale was applied to resolve the different stimuli and background luminance existing between the two devices. There was a strong ceiling effect with the MP-1 in the healthy group, with 90.1% (1136 of 1260) test points clustered at 20 dB. The mean sensitivity for the corresponding points in the OCT/SLO was 25.8 ± 1.9 dB. A floor effect was also observed with the OCT/SLO in the maculopathy group with 9.7% (128 of 1316) points clustered at 9-dB values. The corresponding mean sensitivity in the MP-1 was 1.7 ± 3.9 dB. A regression equation between the two microperimeters was established in the common 10 to19 dB inte...
Crosswell seismic surveys were conducted at two fields in northern Michigan. One of these, Spring... more Crosswell seismic surveys were conducted at two fields in northern Michigan. One of these, Springdale, included two monitor wells that are located external to the reef, and the other, Coldspring, employed two production wells within the reef. The Springdale wells ...
Abu Dhabi International Petroleum Exhibition and Conference, 2010
Tetrahedron Letters, 2008
Proceedings of the National Academy of Sciences, 2013
X-ray computed tomography is a powerful non-invasive imaging technique for viewing an object'... more X-ray computed tomography is a powerful non-invasive imaging technique for viewing an object's inner structures in two-dimensional cross-section images without the need to physically section it. The invention of CT techniques revolutionised the field of medical diagnostic imaging because it provided more detailed and useful information than any previous non-invasive imaging techniques. The method is increasingly being used in industry, aerospace, geosciences and archaeology. This paper describes the development of an X-ray computed tomography system for imaging of industrial materials. The theoretical aspects of CT scanner, the system configurations and the adopted algorithm for image reconstruction are discussed. The penetrating rays from a 160 kV industrial X-ray machine were used to investigate structures that manifest in a manufactured component or product. Some results were presented in this paper.
Journal of Natural Products, 2014
Two new diterpene glycosides in addition to five known glycosides have been isolated from a comme... more Two new diterpene glycosides in addition to five known glycosides have been isolated from a commercial extract of the leaves of Stevia rebaudiana. Compound 1 (rebaudioside KA) was shown to be 13-[(O-β-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid 2-O-β-d-glucopyranosyl-β-d-glucopyranosyl ester and compound 2, 12-α-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester. Five additional known compounds were identified, rebaudioside E, rebaudioside M, rebaudioside N, rebaudioside O, and stevioside, respectively. Enzymatic hydrolysis of stevioside afforded the known ent-kaurane aglycone 13-hydroxy-ent-kaur-16-en-19-oic acid (steviol) (3). The isolated metabolite 1 possesses the ent-kaurane aglycone steviol (3), while compound 2 represents the first example of the isomeric diterpene 12-α-hydroxy-ent-kaur-16-en-19-oic acid existing as a glycoside in S. rebaudiana. The structures of the isolated metabolites 1 and 2 were determined based on comprehensive 1D- and 2D-NMR (COSY, HSQC, and HMBC) studies. A high-quality crystal of compound 3 has formed, which allowed the acquisition of X-ray diffraction data that confirmed its structure. The structural similarities between the new metabolites and the commercially available stevioside sweeteners suggest the newly isolated metabolites should be examined for their organoleptic properties. Accordingly rebaudiosides E, M, N, O, and KA have been isolated in greater than gram quantities.
Bioorganic & Medicinal Chemistry Letters, 2014
Amino acid conjugates of quinolone, metronidazole and sulfadiazine antibiotics were synthesized i... more Amino acid conjugates of quinolone, metronidazole and sulfadiazine antibiotics were synthesized in good yields using benzotriazole methodology. All the conjugates were screened for their antibacterial activity using methods adapted from the Clinical and Laboratory Standards Institute. Antibiotic conjugates were tested for activity in four medically relevant organisms; Staphylococcus aureus (RN4220), Escherichia coli (DH5α), Pseudomonas aeruginosa (PAO1), and Bacillus subtilis (168). Several antibiotic conjugates show promising results against several of the strains screened.
Bioorganic & Medicinal Chemistry, 2008
Global Biotechnology Congress July 22-25 2015, Boston, MA, USA
Broad themaicareas: Trace elements as contaminants and nutrients Ecotoxicology Greenrooftec... more Broad themaicareas:
Trace elements as contaminants and nutrients
Ecotoxicology
Greenrooftechnology
Phytoremediation
Model plants for phytoremediationresearch: Lemna, Eichhornia, Phragmites, Salix, Sorghum, Helianthus, Tobacco, Typha
Enzymes, proteins and genes involved in trace metal tolerance and phytoremediation
Halophytic plants and their potential in the phytoremediation
Microbe assisted phytoremediation
Engineered vegetative covers
Phytomonitoring
Wetland plants for monitoring of trace elements
Constructed wetlands
The use of higher plants as biomonitors/ indicators
Ruderal plants and biomonitoring of trace elements
Phytoproductsand sustainable developmentPlease
Effect of cement particulates deposition on eco-physiological behaviors of halophytes in the salt... more Effect of cement particulates deposition on eco-physiological behaviors of halophytes in the salt marshes of Red Sea, Saudi Arabia
Amal Abdul Rahmana and Mohamed M. Ibrahimb
a Umm Al Qura University, Girls College, Biology department
b King Saud University, P.O. Box 4341 Riyadh 11491
E. mail: mibrahim@ksu.edu.sa
Abstract
The effect of cement dust on pigments status, a critical parameter in the theory of optimal leaf longevity, was studied for five halophytic species native to the Red Sea salt marshes. The plant species selected for the study were Zygophyllum coccineum, Salsola tetrandra, Cyperus conglomeratus, Limonium axillare and Suaede vermiculata. Measurements were taken on plants closed to early constructed cement factory in the area (about 500 m) and other (about 4500-5000 m) far from the factory. Cement dust increased the mortality of young branches leading to a reduction in the height and cover of the five species, especially Salsola tetandra and Suaede vermiculata, which were most sensitive to the dust. Plants responded to dust accumulation in a different pattern especially, photosynthetic pigments, pH of the cell sap, elements (Mg, Mn, Fe, and N) which affected on biosynthesis of pigments, carbohydrates and proteins contents. In most studied species, photosynthetic pigments including chl a, b and carotenoids were negatively correlated with dust deposition and positively correlated with the more distance from the factory. Photosynthetic pigments were declined faster with cement accumulation in Salsola tetandra and Limonium axillare than in Zygophyllum coccineum and Suaeda vermiculata, whereas, increased significantly in Cyperus conglomerotus. Total carbohydrates and protein contents were decreased only with leaves of Salsola tetandra and Suaeda vermiculata, whereas, increased significantly near to the factory and parallel to dust accumulation in the other studied plants. The present work may indicated that cement dust pollution greatly affect the photosynthetic pigments of salt marsh studied species, disturbing the pH of the cell sap, decreased total nitrogen and interrupted the metabolism of soluble amino acids and soluble sugars into insoluble reserve substances.
Key words: halophytic species –cement dust- photosynthetic pigments- Saudi Arabia