Nihal Shams El Din - Academia.edu (original) (raw)

Papers by Nihal Shams El Din

Scientific Reports, 2022

The purpose of this study was to test the nematicidal activity of extracts of two marine algae (C... more The purpose of this study was to test the nematicidal activity of extracts of two marine algae (Colpomenia sinuosa and Corallina mediterranea) and their synthesized silver nanoparticles against root-knot nematodes (Meloidogyne incognita) that infest tomato plants. Scanning electron microscopy (SEM) revealed that nanoparticles had aggregated into anisotropic Ag particles, and transmission electron microscopy (TEM) revealed that the particle sizes were less than 40 nm. Fourier Transform Infrared Spectroscopy (FT-IR) analysis revealed that the obtained nanoparticles had a sharp absorbance between 440 and 4000 cm−1, with 13 distinct peaks ranging from 474 to 3915 cm−1. Methylene chloride extracts and nanoparticles synthesized from both algae species were used to treat M. incognita. C. sinuosa nanoparticles had the highest nematicidal activity of any treatment. Furthermore, and in contrast to other treatments, C. sinuosa nanoparticles reduced the number of nematode galls, egg-masses per ...

Phycologia, 2021

ABSTRACT The Mediterranean Sea is a hotspot for introduced marine species, including seaweeds. Am... more ABSTRACT The Mediterranean Sea is a hotspot for introduced marine species, including seaweeds. Among red algae, Grateloupia, with no less than eight introduced species, occupies a prominent position. Here, we report a large foliose Grateloupia species collected in Eastern Harbour, Alexandria, Egypt, which had previously been reported as G. acuminata and G. doryphora. Comparison of rbcL gene sequences revealed that the specimens represent G. gibbesii, a species originally described from Charleston, South Carolina, USA and potentially distributed in the warm temperate and tropical western Atlantic Ocean. The species has been known only from a single location in Alexandria since the early 1990s, it has not been reported in extensive surveys prior to that date, and there are no reports from other Mediterranean sites. This indicates a recent introduction, with shipping the likely vector. We describe the vegetative and reproductive morphology of G. gibbesii as the basis for evaluating variation in female reproductive structures and generic concepts in Grateloupia.

Oceanologia, 2021

Abstract This study gives updated information on the isolation of ulvan from green alga Ulva fasc... more Abstract This study gives updated information on the isolation of ulvan from green alga Ulva fasciata Delile in Egypt through isolation and chemically characterization of sulfate polysaccharides by two sequential extraction steps using different solvents; distilled water, HCl and Na2EDTA forming fraction I (F-I). Fraction II (F-II) was obtained from remaining seaweeds using NaOH to give FDWNaOH, FHClNaOH, and FEDTANaOH. All products obtained were tested for their biological activities. The highest polysaccharides total extraction yield was 11.8% for water extract (F-I& F-II). The highest protein content was found in FEDTANaOH (2.44%). The highest sulfate content was recorded for F-I (HCl) (21.38%). Total carbohydrates range was (11.99–63.90%) for F-I and (15.06–76.65%) for F-II. Monosaccharides; galactose, rhamnose, and uronic acid were detected at all fractions, with concentrations varying from 0.11 to 1.34%, from 0.61 to 1.81% and from 11.06 to 19.30%, respectively. H1 NMR of (F-II) demonstrated the signals of ring and methyl protons of polysaccharide. The appearance of the stretching bands of the sulfate ester (C-O-S) and sulfate groups (S=O) in the FT-IR spectrum of FHClNaOH confirmed the presence of sulfated polysaccharides, typical of ulvan. The microbial species Vibrio damsela was the most susceptible to FDWNaOH, followed by Aeromonas hydrophila and Vibrio fluvialis with inhibition zones of 30, 22, 22 mm at 150 mg/ml, respectively. FDWNaOH was the most effective fraction having antifouling property. The highest antioxidant activity was observed for F-IHCl followed by FDWNaOH. At concentrations 25 and 50 mg/l,FEDTANaOH displayed the highest anti-inflammatory activity (94.0 and 91.40%, respectively).

International Journal of Phytoremediation, 2021

This study aimed to evaluate the nematicidal activity of two marine algae (Colpomenia sinuosa and... more This study aimed to evaluate the nematicidal activity of two marine algae (Colpomenia sinuosa and Corallina mediterranea) extracts and their synthesized silver nanoparticles against the root-knot nematode (Meloidogyne incognita) infecting tomato plant. Scanning Electron Microscope (SEM) showed that the obtained nanoparticles were aggregated in anisotropic Ag particles. Transmission Electron Microscope (TEM), results showed the particles size was less than 40 nm. Whenever, FT-IR analysis spectrum presented sharp absorbance between 440 and 4000 cm-1 for the obtained nanoparticles, with 13 distinct peaks ranged from 3915 − 474.Both of methylene chloride extract and its synthesized green silver nanoparticles were applied against the M. incognita. The results indicated that the synthesized silver nanoparticles of C. sinuosa exhibited the highest nematicidal activity. Besides, they reduced number of nematode galls, number of egg-masses per root and eggs/egg mass, as well as growth paramet...

Egyptian Journal of Aquatic Biology and Fisheries, 2019

In this investigation, optimization experiments were carried on lipid extraction and biodiesel pr... more In this investigation, optimization experiments were carried on lipid extraction and biodiesel production parameters from Ulva fasciata as a potential feed stock. This study was carried by running one to one optimization model. The results showed that, the highest yield and the best quality of biodiesel was achieved at the optimum condition of <0.16 mm algal particle size, 55 o C extraction temperature, 25:1 v/w solvent to solid ratio, 60 min extraction time and 250 rpm shaking speed, using chloroform: methanol: H 2 O (2: 2: 1) solvent mixture. The recorded lipid yield was 28.84 mg g-1 with total fatty acids ΣTFAs content 1148.94 µg g-1 , saturated fatty acids ΣSFAs=979.43 µg g-1 , monounsaturated ΣMUFAs=136.98 µg g-1 and polyunsaturated ΣPUFAs fatty acids =32.53 µg g-1. The quality of the produced biodiesel at these optimum conditions was determined by its physicochemical properties which showed a very high quality. Cetane number (CN) was 73.21, while kinematic viscosity (υ), density (ρ), higher heating value (HHV) and iodine value (IV) were 4.68 mm 2 s-1 , 0.87 g cm-3 , 39.85 MJ kg-1 and 18.48 gI 2 100g-1 fat, respectively. Other properties such as degree of unsaturation (DU), saponification value (SV) and long chain saturation factor (LCSF) recorded 17.58, 200.66mg KOHg-1 and 23.06, respectively. On the other hand, Linolenic acid (C18:3) % and Polyunsaturated fatty acid methyl esters containing ≥ 4 double bonds % recorded 0.68% and 0.98%, respectively. The initial extraction rate (h) was 6.169 ml g-1 min-1 ; the extraction capacity (Cs) was 31.036 g ml-1 ; the second order extraction constant (k) was 0.0064 ml g-1 min-1 and the coefficient of determination (R 2

Environmental monitoring and assessment, 2014

Concentrations of Cu, Zn, Cd, Pb, Ni, Co, Fe, Mn, and Hg were measured successively in water, sed... more Concentrations of Cu, Zn, Cd, Pb, Ni, Co, Fe, Mn, and Hg were measured successively in water, sediments, and six macroalgal species belonging to three algal classes during 3 years (2008-2010) from Abu Qir Bay, Alexandria, Egypt: Chlorophyceae (Enteromorpha compressa, Ulva fasciata), Phaeophyceae (Padina boryana), and Rhodophyceae (Jania rubens, Hypnea musciformis, Pterocladia capillacea). The study aimed to assess the bioaccumulation potential of the seaweeds, as well as to evaluate the extent of heavy metal contamination in the selected study site. Metals were analyzed using atomic absorption spectrophotometry coupled with MH-10 hydride system. The obtained data showed that the highest mean concentrations of Cu, Zn, Fe, and Mn were recorded in E. compressa; Cd, Ni, and Hg exhibited their highest mean concentrations in P. boryana, while Pb and Co were found in J. rubens. Abundance of the heavy metals in the algal species was as follow: Fe > Mn > Zn > Pb > Ni > Co >...

The Egyptian Journal of Aquatic Research, 2013

The nutritional value of the two seagrasses Cymodocea nodosa and Posidonia oceanica and their pot... more The nutritional value of the two seagrasses Cymodocea nodosa and Posidonia oceanica and their potential use as fertilizers were evaluated based on the determination of biochemical content, major and trace element content in the leaves of the two species, occurring in five sites along the western Egyptian Mediterranean coast during summer (2006 and 2009). The total carbohydrates, total proteins and total lipids in C. nodosa were 47.22, 510.44 and 100.78 mg/g, respectively, and in P. oceanica 28.98, 607.50 and 40.50 mg/g, respectively. The calorific content was 4.03 K cal/g for C. nodosa and 3.93 K cal/g for P. oceanica. N%, P 2 O 5 % and K 2 O% and C:N ratio were 8.45%, 1.21%, 0.81% and 1.50:1 in C. nodosa, respectively, and 10.60%, 2.13%, 0.58% and 1.25:1 in P. oceanica, respectively. The concentrations of trace elements (Cu, Ni, Pb and Zn) in the two species were lower than in composts, while the major element concentrations in C. nodosa coincided with the typical concentrations in composts (P, 530.00; Na, 1044.44; Ca, 2470.00 mg/ 100 g), respectively, but higher in P. oceanica (P, 930.00; Na, 2765.00; Ca, 3890.00 mg/100 g), respectively. Cymodocea nodosa only can be potentially used as supplementary powdered organic fertilizer and/or additive compost.

The phytoplankton community in the stressed part of Abu Qir Bay was studied monthly relative to t... more The phytoplankton community in the stressed part of Abu Qir Bay was studied monthly relative to the prevailing ecological conditions from April 1998 to March 1999 at eight stations. The study recorded a total of 182 species of both fresh and marine origins, belonging to diatoms (89 species), chlorophytes (34 species), dinoflagellates (26 species), cyanophytes (18 species), euglenophytes (12 species), silicoflagellates (2 species), and cryptophyte (one species). Most of the recorded species occurred either seasonally or rarely, while small number of them appeared as persistent. The diversity of the phytoplankton community experienced wide variations on both monthly and spatial scales, accompanied by analogous variations in the diversity index, richness and evenness. The phytoplankton count was low (0.01 x 103 - 12.5 x 103 unit/L) all the year round, except high density in September (55.6 x 103 units/L). In contrast, chlorophyll-a attained markedly high values over the year (2.06 - 52...

International Journal of Approximate Reasoning, 2021

The green algae Ulva faciata was subjected to different physical pretreatments comprising thermal... more The green algae Ulva faciata was subjected to different physical pretreatments comprising thermal and mechanical techniques at different experimental conditions to state the most appropriate method of cell disruption for increasing the quantity of the extracted lipid and hence improve the quality of the produced biodiesel with low cost. Thermal pretreatment was autoclaving of either wet or dry algal biomass, while mechanical pretreatments include microwave and ultrasonication at different time intervals. The control was the alga without pretreatment extracted at optimum conditions: 60 min, 55oC, shaking speed at 250 rpm, < 0.16 mm particle size with 25:1 v/w solvent to solid ratio. The results showed that the quantity of extracted lipids in case of using all physical pretreatments increased the Total fatty acids yield significantly by about 2-folds of the control for wet algae in hydrothermal treatment with optimum time of treatment 40 minutes, and 1.4 folds for dry algae in ther...

Egyptian Journal of Aquatic Biology and Fisheries

Chemical pretreatment of Ulva fasciata cell wall for enhancing biodiesel yield __________________... more Chemical pretreatment of Ulva fasciata cell wall for enhancing biodiesel yield _________________________________________________________________________________________

Desalination and Water Treatment, 2016

AbstractScale deposition and corrosion have become a nightmare for any oil and gas operations. Th... more AbstractScale deposition and corrosion have become a nightmare for any oil and gas operations. The antiscalant properties of the green algal (Ulva compressa) and the red algal (Pterocladiella capillacea) extracts were studied using conductivity, electrochemical impedance spectroscopy (EIS), and chronoamperometry techniques in conjunction with microscopic and infrared examinations. The corrosion inhibitive characteristics were investigated using EIS and potentiodynamic polarization measurements. Mineral scales were deposited from the brine solution by cathodic polarization of the steel surface at −0.9 V (vs. SCE). Potentiodynamic polarization curves indicated that the green algal (U. compressa) and the red algal (P. capillacea) extracts inhibit the corrosion of steel by controlling the cathodic oxygen reduction process.

Journal of applied microbiology, Jan 26, 2018

To screen the newly recorded alga Grateloupia doryphora in the Egyptian Mediterranean Sea for ant... more To screen the newly recorded alga Grateloupia doryphora in the Egyptian Mediterranean Sea for antimicrobial activity. Algal samples were collected from the Eastern Harbor, Alexandria, Egypt during summer (2016 and 2017). The dry and fresh methanolic, ethanolic and ethyl acetate algal extracts were tested against Bacillus subtilis, Enterococcus faecalis, and Staphylococcus aureus as gram-positive bacteria, Escherichia coli, Pseudomonas aeruginosa as gram-negative bacteria and one yeast strain Candida albicans. A three way analysis of variance (ANOVA) showed significant differences based on the algal form, type of solvents and microbial species. The fresh methanolic and ethyl acetate extracts had equal effects on the tested pathogens with means of 14.44 and 15.16, respectively. However, the fresh algal extract was more effective on all the tested organisms than the dried material, except for ethyl acetate and ethanol extract on B. subtilis (31 and 23 mm), respectively. In fact, P. aer...

In this study, fatty acids profile was determined in four algal species; namely Ulva fasciata (Ch... more In this study, fatty acids profile was determined in four algal species; namely Ulva fasciata (Chlorophyta), Corallina mediterranea, Corallina officinalis and Pterocladiella capillacea (Rhodophyta) which were collected from two sites (Abu-Qir Bay and Eastern Harbor) located on the Egyptian Mediterranean Sea during the four seasons in the period (2011-2012). In addition, nutrient content in the algal species (total nitrogen and phosphorus) and the environmental conditions of the ambient sea water were measured to find out their effect on the algal fatty acids content. The nitrogen content in algal species was almost equal in both sites. In contrast, the phosphorus content was higher in Abu-Qir (0.33-1.71%) than in Eastern Harbor (0.21-0.74%). The fatty acids profile showed different correlations with water's physico-chemical properties. The fatty acids profile of the four algal species revealed high content of SFAs against MUFA and PUFA in both sites. Consequently, the algae were screened to define the suitable site, season and species for the highest quality and quantity of biodiesel production. Biodiesel physical properties; the Degree of Unsaturation (DU), Long Chain Saturation Factor (LCSF), Cold Filter Plugging Point (CFPP), Iodine Value (IV), Saponification Value (SV), the Cetane Number (CN), Kinematic viscosity (υ), density (ρ), the Higher Heating Value (HHV), C18:3% (wt%) and double bond Db ≥4(wt%) were calculated. All the investigated algae showed biodiesel properties that follow the standard values set for optimum biodiesel, with the green alga U. faciata collected from Abu-Qir during winter, as the best choice for producing biodiesel; whereas, the extracted fatty acids from Corallina officinalis is more suitable to be used for production of blenders, which can be added to the petroleum diesel in order to increase its quality, oxidative stability and octane number.

Revista de biología marina y oceanografía, 2015

Agarófitas marinas asociadas con bacterias epifitas de la costa de Alejandría, Egipto, con énfasi... more Agarófitas marinas asociadas con bacterias epifitas de la costa de Alejandría, Egipto, con énfasis en la evaluación y extracción de agar y agarosa

Environmental Monitoring and Assessment, 2016

species), and Chlorophyceae (4 species). The results indicated a relative high occurrence of some... more species), and Chlorophyceae (4 species). The results indicated a relative high occurrence of some species namely.; Pleurotaenium trabecula of green algae; Chaetoceros lorenzianus, Proboscia alata var. gracillima, Pseudosolenia calcar avis, and Pseudonitzschia pungens of diatoms; Trichodesmium erythraeum and Pseudoanabaena limnetica of cyanophytes. Most of other algal species were fairly distributed at the selected stations of the study area. The total abundance of phytoplankton was relatively low (average of 2989 unit/L) in the eastern coast of Suez Gulf, as compared its western coast and the northern part of the Red Sea. The diversity of phytoplankton species was relatively high (2.35-3.82 nats) with an annual average of 3.22 nats in the present study. The results concluded that most of eastern coast of Suez Gulf is still healthy, relatively unpolluted, and oligotrophic to mesotrophic area, which is characterized by the low values of dissolved phosphate (0.025-0.3 μM), nitrate (0.18-1.26 μM), and relatively high dissolved ammonium (0.81-5.36 μM). Even if the occurrence of potentially harmful algae species was low, the study area should be monitored continuously. The dissolved oxygen ranged between 1.77 and 8.41 mg/L and pH values between 7.6 and 8.41. The multiple regression analysis showed that the dissolved nitrate and pH values were the most effective factors that controlled the seasonal fluctuations of phytoplankton along the eastern coast of Suez Gulf during 2012-2013.