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Design, synthesis and cytotoxic activity of watersoluble quinones with dibromo-p-benzoquinone
cores and amino oligoIJethylene glycol) side chains
against MCF-7 breast cancer cells

Research Abstract
A series of novel quinones was synthesized by reacting tetrabromo-p-benzoquinone with amino oligoIJethylene glycol) dendrons of generation numbers g = 0–2. According to the performed shake-flask experiments, their aqueous solubility (S = 18 mg l−1 –1.6 g ml−1 ) and partition coefficients (logPoct/wat = 2.53–0.21) can be tuned in a wide range as a function of g. In vitro cytotoxicity assays of tetrabromo-pbenzoquinone and its derivatives against MCF-7 human breast cancer cells showed a concentration- and generation-specific biological activity with IC50-values as low as 0.8 μM. Further investigations revealed a considerable selectivity against cancer cells, as indicated by a weak cytotoxicity against human skin fibroblast cells (>80% survival) within the studied range of concentrations. The results demonstrate that these novel amino oligoIJethylene glycol) dendrons depict versatile tools to ameliorate physical and pharmacological characteristics of extremely hydrophobic molecules and make them susceptible to biological applications.
Research Authors
Leon F. Scherz, Engy A. Abdel-Rahman, Sameh S. Ali, A. Dieter Schlütera and Mona A. Abdel-Rahman
Research Journal
MedChemComm
Research Pages
pp. 662 - 672
Research Publisher
NULL
Research Rank
1
Research Vol
Vol. 8
Research Website
NULL
Research Year
2017

Annotated Outdoor Image Compression Based on Sky Replacement

Research Abstract
the sky is a basic component in outdoor images. Due to the low gradient values of the sky, it has high priority in seam removing for content aware image resizing and the result of enlarging image contributes obvious artificial pixels. The proportion of images which contains sky is over 40% of the daily recent explored images on Flickr (see section V). This paper presents a new technique for annotated outdoor image compression (AOIC) depending on sky replacing. We compress the outdoor images by replacing the sky region with the nearest sky in a predefined sky database to reduce image size. Our work is composed of two stages: encoding stage and decoding stage. In the encoding stage, we use sky annotation polygon to distinguish sky and non-sky regions. The sky features are extracted from the sky region (e.g. sky type, mean HSV, cloud type, and sun existence/relative position). These features are used to find the nearest sky feature from a predefined database of sky features. The sky ID and the sky polygon vertices are composed with non-sky region image. On the decoding stage, we use the sky ID to load the sky from the predefined sky database and compose the sky with the non-sky region (compressed image). Our method is tested using the standard outdoor images of LabelMe database which contain sky. Our method removes the sky and replaces it instead of shrinking the sky region in content aware image resize. Our AOIC can be used for reducing the file size of any image formats of outdoors that contains sky.
Research Authors
Khaled F. Hussain

Hanaa A. Sayed
Research Journal
The 27th International Conference on Computer Theory and Applications
Research Pages
32-37
Research Publisher
NULL
Research Rank
3
Research Vol
NULL
Research Website
https://iccta.aast.edu/2017/index.php
Research Year
2017

New Set of Multi-Channel Orthogonal Moments for Color Image Representation and Recognition

Research Abstract
Orthogonal moments and their invariants to similarity transformations for monochrome and gray-scale images are widely used in many pattern recognition and image processing applications. Quaternion orthogonal moments are used with color images. Recently, the multi-channel framework is proposed as a successful alternative of the quaternion orthogonal moments in representation and recognition of the color images. In this paper, a new set of multi-channel orthogonal moments and their invariants to rotation, scaling and translation (RST) is proposed for color image representation and recognition. The proposed multi-channel moments are based on the orthogonal radial substituted Chebyshev functions. The multi-channel orthogonal radial substituted Chebyshev moments (MORSCMs) are defined in polar coordinates over a unit circle. An accurate kernel-based method is utilized for accurate computation of the MORSCMs. A series of experiments is performed to validate this new set of multi-channel moments and compare its performance with the existing quaternion and multi-channel orthogonal moments. The obtained results ensure the superiority of the proposed MORSCMs over all existing moments in representation and recognition of the color images.
Research Authors
Khalid M Hosny, Mohamed M Darwish
Research Journal
Pattern Recognition
Research Pages
153-173
Research Publisher
Pergamon, Elsevier.
Research Rank
1
Research Vol
Volume 88
Research Website
https://www.sciencedirect.com/journal/pattern-recognition
Research Year
2019

In Vitro Comparative Evaluation of Antioxidant Activity of Hydrophobic and Hydrophilic Extracts from Algicolous Fungi

Research Abstract
The screening of potential antioxidant activities of hydrophobic (ethyl acetate) and hydrophilic (polysaccharide) extracts from both mycelia and fermentation media of eleven algicolous fungi was performed using three antioxidant assays. Algicolous fungi were able to ferment low-cost nutrients composed of potato infusion, glucose, and natural seawater and produce hydrophobic and hydrophilic metabolites with antioxidant properties. Significant differences were observed in antioxidant activities of extracts from the various species evaluated using total antioxidant activity (TAA), hydroxyl radical scavenging activity (HRSA), and ferric reducing antioxidant power (FRAP), as well as their total sugar contents (TSC) of hydrophilic extracts and total phenolic contents (TPC) of hydrophobic extracts. TSC of endopolysaccharides was higher than exopolysaccharides and showed a significant correlation with both TAA and FRAP. Most of mycelial extracts were richer in phenolics than fermentation media, and TPC of hydrophobic extracts was significantly correlated with their FRAP. Mycelial extracts for most of algicolous fungi showed higher antioxidant activities than fermentation media. Both hydrophobic and hydrophilic extracts of algicolous fungi showed good antioxidant properties, especially as hydrogen-donating antioxidants, which could be considered for future applications in medicine, food production, or cosmetic industry.
Research Authors
Awatief F. Hifney, Mustafa A. Fawzy, Khayria M. Abdel-Gawad, Ahmed A. Issa,Mohamed Gomaa
Research Journal
Journal of Aquatic Food Product Technology
Research Pages
124-131
Research Publisher
NULL
Research Rank
1
Research Vol
26
Research Website
NULL
Research Year
2017

Fungal Agarase Production in a Cost-Effective Macroalgal Based Medium and Enzymatic Hydrolysis of the Alkali Extracted Macroalgal Biomass: An Optimization Study

Research Abstract
Agarase is a promising biocatalyst that catalyze the hydrolysis of agar or agarose and produce oligosaccharides with several biotechnological applications. Agarase production by Dendryphiella arenaria was optimized using a natural low-cost medium composed of the red alga Palisada perforata and natural seawater. The results showed that seaweed biomass and seawater concentrations were the most important factors influencing agarase production. After optimization, the agarase activity was enhanced to 2.5 ± 0.3 U/mL. The crude agarase exhibited a wide pH (4‒10) stability with residual activity more than 75%. The enzyme showed high thermostability at 40 °C, and a moderate thermostability at 50, 60, 70 °C. Several parameters of thermal inactivation kinetics and thermodynamics were calculated, and suggested that the enzyme would be thermostable. Enzymatic saccharification of alkali extracted polysaccharides from the red macroalgal biomass was also optimized with respect to substrate concentration, enzyme dosage, and temperature and proceeded optimally at 0.15% substrate, 40 °C with enzyme dosage 0.9 mL/mL substrate. Under these conditions, the enzymatic saccharification yielded 647.96 mg reducing sugars/g substrate. This study therefore describes an improved, effective, and low-cost process for agarase and fermentable sugar production from seaweed biomass.
Research Authors
Mustafa A. Fawzy, Mohamed Gomaa, Awatief F. Hifney, Khayria M. Abdel-Gawad
Research Journal
Waste and Biomass Valorization
Research Pages
NULL
Research Publisher
NULL
Research Rank
1
Research Vol
NULL
Research Website
NULL
Research Year
2018

Use of seaweed and filamentous fungus derived polysaccharides in the
development of alginate-chitosan edible films containing fucoidan:
Study of moisture sorption, polyphenol release and antioxidant
properties

Research Abstract
Alginate and fucoidan extracted from the brown macroalga Sargassum latifolium and chitosan derived from the filamentous fungus Aspergillus niger were used for the development of edible films with natural antioxidant properties. The incorporation of fucoidan and/or Ca2þ into the alginate-chitosan films decreased water solubility, but increased film thickness, water vapor permeability and oxygen permeability. The developed films showed good barrier properties against ultraviolet light. The interactions between film components were investigated using FTIR analysis which confirmed the presence of hydrogen bonded interaction. Kinetics of moisture sorption and polyphenol release exhibited a good fit to Peleg's model. Film moisture content at equilibrium was increased by fucoidan blending. Additionally, the water vapor diffusion and polyphenol release were expressed in terms of effective diffusion coefficient based on simplified Fick's second law. The developed films exhibited good antioxidant properties as measured by total antioxidant assay, ferric reducing antioxidant power and hydroxyl radical scavenging activity. Both film type and the type of the food simulant markedly affected the polyphenol release and the subsequent antioxidant activity of the films.
Research Authors
Mohamed Gomaa*, Awatief F. Hifney, Mustafa A. Fawzy, Khayria M. Abdel-Gawad
Research Journal
Food Hydrocolloids
Research Pages
pp. 239 - 247
Research Publisher
NULL
Research Rank
1
Research Vol
Vol. 82
Research Website
NULL
Research Year
2018

Use of the brown seaweed Sargassum latifolium in the design of
alginate-fucoidan based films with natural antioxidant properties and
kinetic modeling of moisture sorption and polyphenolic release

Research Abstract
Alginate and fucoidan are unique polysaccharides present in brown algae and widely used in food and medical technologies. Alginate and fucoidan were sequentially extracted from Sargassum latifolium and used for the preparation of alginate and alginate-fucoidan blend films with or without Ca-crosslinking. The incorporation of fucoidan and Ca2þ decreased water solubility, but increased film thickness, water vapor permeability and oxygen permeability. The films showed good properties against ultraviolet light, however, incorporation of fucoidan and/or Ca2þ decreased the color parameter L* value and increased the a* and b* values of the films. The interaction of Ca2þ and fucoidan with alginate was investigated using FTIR analysis which confirmed the presence of hydrogen bonded interaction. Kinetics of moisture sorption and polyphenol release exhibited a good fit to Peleg's model. Ca2þ crosslinking decreased initial moisture sorption and increased the maximum sorption capacity of the films. Additionally, the water vapor diffusion and polyphenol release were expressed in terms of effective diffusion coefficient based on simplified Fick's law. The developed films showed good antioxidant properties as measured by total antioxidant assay, ferric reducing antioxidant power and hydroxyl radical scavenging activity. Both film type and the type of the food simulant markedly affected the polyphenol release and the antioxidant activity of the films.
Research Authors
Mohamed Gomaa* , Mustafa A. Fawzy, Awatief F. Hifney, Khayria M. Abdel-Gawad
Research Journal
Food Hydrocolloids
Research Pages
pp. 64 - 72
Research Publisher
NULL
Research Rank
1
Research Vol
Vol. 82
Research Website
NULL
Research Year
2018

Statistical Optimization of Culture Variables for Enhancing
Agarase Production by Dendryphiella arenaria Utilizing Palisada
perforata (Rhodophyta) and Enzymatic Saccharification
of the Macroalgal Biomass

Research Abstract
Agarase is a promising biocatalyst for several industrial applications. Agarase production was evaluated by the marine fungus Dendryphiella arenaria utilizing Palisada perforata as a basal substrate in semi-solid state fermentation. Seaweed biomass, glucose, and sucrose were the most significant parameters affecting agarase production, and their levels were further optimized using Box-Behnken design. The maximum agarase activity was 7.69 U/mL. Agarase showed a degree of thermostability with half-life of 99 min at 40 °C, and declining to 44.72 min at 80 °C. Thermodynamics suggested an important process of protein aggregation during thermal inactivation. Additionally, the enzymatic saccharification of the seaweed biomass using crude agarase was optimized with respect to biomass particle size, solid/liquid ratio, and enzyme loadings. The amount of biosugars obtained after optimization was 26.15 ± 1.43 mg/g. To the best of our knowledge, this is the first report on optimization of agarase in D. arenaria.
Research Authors
Mohamed Gomaa1 & Awatief F. Hifney1 & Mustafa A. Fawzy1 &
Khayria M. Abdel-Gawad1
Research Journal
Mar Biotechnol
Research Pages
pp. 592–600
Research Publisher
NULL
Research Rank
1
Research Vol
Vol. 19
Research Website
NULL
Research Year
2017

ON φ-COINCIDENCE AND COMMON φ- FIXED POINTS IN ORDERED METRIC
SPACES

Research Abstract
The aim of this work is to obtain some existence and uniqueness fixed point theorems for mixed gmonotone mapping in any number of variables under general contractive conditions in partially ordered metric spaces by using the condition of weak compatibility. Our results are different, more natural and generalizations of many results on multidimensional fixed points. For illustration of the effectiveness of our generalizations, some examples are equipped in this paper
Research Authors
R. A. RASHWAN, I. M. SHIMAA
Research Journal
Adv. Fixed Point Theory
Research Pages
pp. 43-66
Research Publisher
NULL
Research Rank
1
Research Vol
Vol. 6, No. 1
Research Website
NULL
Research Year
2016

Common and coupled random fixed point theorems in S-metric spaces

Research Abstract
The aim of this paper is to prove some common and coupled random xed point theorems for a pair of weakly monotone random operators satisfying some rational type contraction in the setting of partially ordered S-metric space. Our results extend and generalize many existing results in the literature. Moreover, an example is given to support our results. Finally, the results are used to prove the existence and uniqueness of solution of some random functional equations.
Research Authors
Rashwan Ahmed Rashwan, Shimaa Ibraheem Moustafa
Research Journal
Commun. Nonlinear Anal.
Research Pages
pp. 167-182
Research Publisher
NULL
Research Rank
1
Research Vol
Vol. 4
Research Website
NULL
Research Year
2017
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