Mohamed R. Elamin

Bio: Mohamed R. Elamin is an academic researcher. The author has contributed to research in topics: Adsorption & Chemistry. The author has an hindex of 3, co-authored 4 publications receiving 49 citations.

Biological activities of Boswellia sacra extracts on the growth and aflatoxins secretion of two aflatoxigenic species of Aspergillus species

Abstract: Aflatoxins are the most serious carcinogenic, hepatotoxic, teratogenic and mutagenic secondary metabolites which adversely affect human and animal health. This study was designed to evaluate the in vitro inhibitory effect of different concentrations of Boswellia sacra resin (2.5, 5, 7.5 and 10 g/100 ml), leaf extract (5, 7.5, 10, 12.5 and 15 ml/100 ml), and essential oil (1, 2, 3, and 4 ml/100 ml) on the growth and aflatoxins production by two species of Aspergilli, namely Aspergillus flavus (SQU21) and Aspergillus parasiticus (CBS921.7). Resin of B. sacra caused 57.9–92.1% inhibition of aflatoxin secretion by A. flavus and 43.6–95.7% for A. parasiticus. However, the mycelial dry weights were significantly increased by 20.9–52.7% for A. flavus, and 8.9–68.5% for A. parasiticus. The leaf extract of B. sacra apparently enhanced aflatoxins production by 20–50%, and mycelial dry weight by 25.5–29.1% for A. flavus and A. parasiticus. The essential oil of B. sacra at different concentrations similarly inhibited the fungal growth and aflatoxins production by 45.8–83.7% for A. flavus and 41.3–83.5% for A. parasiticus which indicates the antifungal activity of this oil. None of the B. sacra extracts detoxified pure aqueous aflatoxin B1. We have concluded that B. sacra resin and essential oil possess biological activity against biochemical synthesis and metabolic pathway of aflatoxin production of the two Aspergillus species. Therefore, the resin and essential oil of B. sacra can be recommended as safe plant based bioreservatives to enhance shelf life of food and feed products with reference to adverse effect of physical and synthetic chemical preservatives and their antimicrobial and aflatoxins inhibition activity.

Highly Selective Removal of Cationic Dyes from Wastewater by MgO Nanorods

Abstract: The organic synthetic dyes employed in industries are carcinogenic and harmful. Dyes must be removed from wastewater to limit or eliminate their presence before dumping into the natural environment. The current study aims to investigate the use of MgO nanoparticles to eliminate basic fuchsine (BF), as a model cationic dye pollutant, from wastewater. The MgO nanorods were synthesized through a coprecipitation method. The obtained nanocomposite was characterized using various techniques such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Brunauer–Emmett–Teller (BET), and FTIR spectroscopy. It was found that the variation of dye concentration and pH influenced the removal of BF by MgO. The adsorption capacity of 493.90 mg/g is achieved under optimum operating conditions (pH = 11, contact time = 236 min, and initial BF concentration = 200 ppm). Pseudo-second-order adsorption kinetics and Freundlich isotherm models best fitted BF sorption onto MgO nanorods. The BF sorption mechanism is associated with the electrostatic attractions and hydrogen bond between the O–H group of MgO and the NH2 groups of BF, as indicated by the pH, isotherms, and FTIR studies. The reusability study indicates that MgO was effectively used to eliminate BF in at least four continuous cycles. The investigation of MgO with different dyes suggests the high adsorption selectivity of BF, crystal violet (CV), and malachite green (MG) dyes compared with methyl orange (MO) dye. Overall, MgO nanorods can act as a potential and promising adsorbent for the efficient and rapid removal of cationic dyes (CV, MG, and BF) from wastewater.

The Potential of Baobab (Adansonia digitata L.) Extracts as Biocontrol on the Growth and Aflatoxin Production by Aspergillus flavus and A. parasiticus

Abstract: Moulds and associated mycotoxins, especially aflatoxins, are important factors that advesely affect food and feed produced from contaminated plant and animal prodcuts. They are lethal to humans and animals, which emphasizes the great concern in food and feed production. In this study, the effects of baobab (Adansonia digitata) extracts on the vegetative growth and aflatoxin secretion by A. flavus (SQU21) and A. parasiticus (CBS921.7) strains were exzmined. Different concentrations of baobab fruit extract (1.5, 3, 5, and 7% w/v) and essential oil (0.5, 1, 3 and 5% v/v) was used. Fruit extract of baobab apparently inhibited the total aflatoxin secretion up to 20.4-68.5% for A. flavus and 11.9-69.1% for A. parasiticus, whereas the inhibition of aflatoxin B1 production ranged between 29.9-79.2% and 13-68% for the two strains, respectively. The highest inhibition levels of total aflatoxin and aflatoxin B1 secretion by A. flavus (47.2-95.7%; 28.1-89.7%) and A. parasiticus (42.7-93.3%; 25.9-80.2%) were obtained with essential oil extracted from baobab seeds. The two extracts significantly reduced the vegetative growth and the mycelial dry weights of selected fungi. This indicates the antifungal activity and inhibitory effect of baobab on the growth and aflatoxin production by the two toxigenic strains. Thus, fruit extract and essential oil of A. digitata can be suggested as potentially effective biocontrol and biopreservative substrates against food and feed contamination by aflatoxigenic moulds.

Removal of ciprofloxacin and indigo carmine from water by carbon nanotubes fabricated from a low-cost precursor: Solution parameters and recyclability

Abstract: Water contamination is one of humanity's threatening problems. This study synthesized pristine carbon nanotubes (PCNTs) from commercial gasoline (CG) as a relatively low-cost precursor. 200 mL of CG yielded an average CNTs mass of 26.23 ± 0.97 g. The functionalized carbon nanotubes (FCNTs) were produced by acid-treatment of PCNTs, and the yield was 93.3%. The surface area of PCNTs and FCNTs was 29.69 and 66.16 m 2 g −1 . The FTIR and EDX indicated an introduction of oxygenated groups on the FCNTs. The FCNTs removed ciprofloxacin (CIP) and indigo carmine (IC) from water with an adsorption capacity of 95.5 and 93.0 mg g −1 , respectively, while the PCNTs showed 78.9 and 63.7 mg g −1 , respectively. The pH 4.0 and 6.0 suited the adsorption of CIP and IC on both sorbents. The adsorption processes for all sorbent-sorbate systems were spontaneous and exothermic. The FCNTs and PCNTs recyclability showed an average efficiency of 90.0%.

Spontaneous Adsorption and Efficient Photodegradation of Indigo Carmine under Visible Light by Bismuth Oxyiodide Nanoparticles Fabricated Entirely at Room Temperature

Abstract: Bismuth oxyiodide (BiOI) is a targeted material for its relative safety and photocatalytic activity under visible light. In this study, a successful simple and energy-saving route was applied to prepare BiOI through a sonochemical process at room temperature. The characterization of the prepared BiOI was conducted by physical means. The transmission electron microscope (TEM) image showed that the BiOI comprises nanoparticles of about 20 nm. Also, the surface area of the BiOI was found to be 34.03 m2 g−1 with an energy gap of 1.835 eV. The adsorption and photocatalytic capacities of the BiOI were examined for the indigo carmine dye (IC) as a model water-pollutant via the batch experiment methodology. The solution parameters were optimized, including pH, contact time, IC concentration, and temperature. Worth mentioning that an adsorption capacity of 185 mg·g−1 was obtained from 100 mg L−1 IC solution at 25 °C within 60 min as an equilibrium time. In addition, the BiOI showed a high degradation efficiency towards IC under tungsten lamb (80 W), where 93% was removed within 180 min, and the complete degradation was accomplished in 240 min. The fabricated BiOI nanoparticles completely mineralized the IC under artificial visible light, as indicated by the total organic carbon analysis.

Short Communication - Studies on the antimicrobial effects of garlic (Allium sativum Linn), ginger (Zingiber officinale Roscoe) and lime (Citrus aurantifolia Linn)

Abstract: The antimicrobial effect in vitro of aqueous and ethanolic extracts of garlic (Allium sativum Linn.), ginger (Zingiber officinale Roscoe) and lime (Citrus aurantifolia Linn.) juice were assayed against Staphylococcus aureus; Bacillus spp., Escherichia coli and Salmonella spp. All the test organisms were susceptible to undiluted lime-juice. The aqueous and ethanolic extracts of garlic and ginger singly did not inhibit any of the test organisms. The highest inhibition zone of 19 mm was observed with a combination of extracts on Staphylococcus aureus. Salmonella spp were resistant to almost all the extracts except lime.

Antifungal, antiaflatoxin and antioxidant potential of chemically characterized Boswellia carterii Birdw essential oil and its in vivo practical applicability in preservation of Piper nigrum L. fruits

Abstract: The study explores the chemical profile, antimicrobial and antioxidant activity of Boswellia carterii essential oil (EO). The EO significantly inhibited growth and aflatoxin production by the food borne toxigenic strain of Aspergillus flavus at 1.75 μl/ml and 1.25 μl/ml respectively. It exhibited broad fungitoxic spectrum against 12 food borne moulds and also showed strong antioxidant activity, IC50 value and % inhibition of linoleic acid peroxidation being 0.64 μl/ml and 51.68% respectively. The antifungal action of EO was observed in terms of reduction in ergosterol content of plasma membrane of A. flavus. As fumigant in food system in storage containers, the EO provided 65.38% protection against fungal deterioration of Piper nigrum. GC–MS results revealed 31 components of EO. The chemically characterized B. carterii EO may thus be recommended as plant based preservative in view of its antifungal, antiaflatoxigenic, antioxidant activity and efficacy in food system.

Development of antibacterial carboxymethyl cellulose/chitosan biguanidine hydrochloride edible films activated with frankincense essential oil

Abstract: This study aims to prepare binary edible films made from carboxymethyl cellulose (CMC) and chitosan biguanidine hydrochloride (CBg) activated with frankincense oil (FO). The interactions between CMC, CBg and FO were confirmed by FTIR. XRD showed that the addition of FO led to decreasing the crystallinity of CMC/CBg films. The water vapour permeability was reduced upon increasing the FO content. The presence of FO made the films brighter and didn't change their transparency as detected from the color measurements. The films exhibited better mechanical properties in the presence of FO as detected from the improved values of both tensile strength and elongation at break. The prepared films exhibited excellent antibacterial activity especially at high content of FO (5%). CMC/CBg/FO films might be used potentially in the production of edible films due to their excellent physical and antibacterial properties.

Evaluation of antifungal activity of essential oils against aflatoxigenic Aspergillus flavus and their allelopathic activity from fumigation to protect maize seeds during storage

Abstract: Four essential oils were evaluated for antifungal activities against ten isolates of Aspergillus flavus. All strains, except A. flavus PSRDC-2, were strongly inhibited by clove (Syzygium aromaticum (L.) Merr. & L.M. Perry) and vatica (Vatica diospyroides Symington) oil. The oils contained 14 and 24 compounds, respectively, with eugenol (62.4%) as the main component of clove oil and benzyl acetate (48.8%) as the main component of vatica oil. Clove oil showed 84.7% inhibition on conidial germination of A. flavus PSRDC-2 at 100 μL L−1, while complete inhibition of disease infection on maize seeds occurred at 10 μL L−1. Vatica oil at 50 μL L−1 exhibited strong antifungal activity as it completely inhibited growth, sporulation, conidial germination, and disease infection of A. flavus PSRDC-2 both in vitro and on maize seeds. Fumigation of vatica oil for 6 h could protect and cure the infected maize seed. Both clove and vatica oils exhibited dose-dependent allelopathic activity on maize germination, stem length, and root length, with vatica oil being more phytotoxic than clove oil.

Structural Elucidation and Toxicity Assessment of Degraded Products of Aflatoxin B1 and B2 by Aqueous Extracts of Trachyspermum ammi.

Abstract: In this study aqueous extract of seeds and leaves of Trachyspermum ammi were evaluated for their ability to detoxify aflatoxin B1 and B2 (AFB1; 100 µg L-1 and AFB2; 50 µg L-1) by In Vitro and In Vivo assays. Results indicated that T. ammi seeds extract was found to be highly significant (P < 0.05) in degrading AFB1 and AFB2 i.e. 92.8% and 91.9% respectively. However T. ammi leaves extract proved to be less efficient in degrading these aflatoxins, under optimized conditions i.e., pH 8, temperature 30˚C and incubation period of 72h. The structural elucidation of degraded toxin products by LCMS/MS analysis showed that eight degraded products of AFB1 and AFB2 were formed. MS/MS spectra showed that most of the products were formed by the removal of double bond in the terminal furan ring and modification of lactone group indicating less toxicity as compared to parent compounds. Brine shrimps bioassay further confirmed the low toxicity of degraded products, showing that T. ammi seeds extract can be used as an effective tool for the detoxification of aflatoxins.