In this study, we have shown the microbial alkaline protease production by using isolated Bacillu... more In this study, we have shown the microbial alkaline protease production by using isolated Bacillus subtilis. Bacillus subtilis which produces an extracellular alkaline protease was isolated from meet surface purchased from local Egyptian markets. Maximum enzyme activity was achieved when the bacterium was grown on corn steep liquor (2.0 %, w/v) instead of soybean meal (2 %) followed by casein hydrolysate (2%, w/v) and 12 % cane sugar molasses as a carbon source at pH 10.0 and 37oC over 24 h incubation period (maximum enzyme production at 48 hr.). The enzyme has an optimum pH of around 10.0 and maintained its stability over a broad pH range between 5.0 to 12.0. Its optimum temperature is around 37 °C, and exhibited a stability of up to 50 oC.
A sequential optimization strategy, based on statistical experimental designs, was employed to en... more A sequential optimization strategy, based on statistical experimental designs, was employed to enhance the production of invertase by Lactobacillus brevis Mm-6 isolated from breast milk. First, a 2-level Plackett–Burman design was applied to screen the bioprocess parameters that significantly influence the invertase production. The second optimization step was performed using fractional factorial design in order to optimize the amounts of variables have the highest positive significant effect on the invertase production. A maximal enzyme activity of 1399 U/ml was more than five folds the activity obtained using the basal medium. Invertase was immobilized onto grafted alginate beads to improve the enzyme’s stability. Immobilization process increased the operational temperature from 30 to 60 ◦C compared to the free enzyme. The reusability test proved the durability of the grafted alginate beads for 15 cycles with retention of 100% of the immobilized enzyme activity to be more convenie...
A newly isolated moderately halophilic bacterial strain from Egyptian hyper saline source was ide... more A newly isolated moderately halophilic bacterial strain from Egyptian hyper saline source was identified as Chromohalobacter salexigens and was selected for its ability to produce extracellular levan. Different environmental and nutritional factors were optimized. These factors including initial pH, temperature, nitrogen source, sodium chloride concentration, phosphorous source in addition to the sequence incubation at optimum and cold temperature. The resulted polymer was identified by paper chromatography, NMR and FT-IR spectroscopy. Also chemical modifications (carboxymethylation and sulphation) were proceeded and the biological activity (fibrinolytic, prebiotic activity) of resulted levan and its derivatives were also determined. The highest quantity of levan (11.9 g l) was produced at pH 8, sodium chloride concentration 15%, ammonium sulphate as nitrogen source and sequence incubation at optimum followed by cold temperature. Chemically modified levan recorded high fibrinolytic ...
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment o... more Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment of various diseases. This study was designed to evaluate the potential of three aqueous extracts of fennel seeds with different extraction conditions (pH 3, 7 and 12) as natural antimicrobial, antiviral, antioxidant and antitumor agents from the safety point of view. The three aqueous extracts were then used for evaluation of yield, total carbohydrates, protein, flavenoid and total phenolic contents. Antioxidant activity was evaluated using the DPPH• radical scavenging. The results showed that the high anti-scavenging activity was noticed for three different aqueous extracts of fennel at 2.0 mg dose comparable to other doses. In addition, the antimicrobial activity of the aqueous extracts against tested Gram positive and negative bacteria, yeast and fungi strains was determined. The extract (concentration 1.6 mg/ ml) was effective against most of the strains tested, yet not against Candid...
Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment o... more Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment of various diseases. This study was designed to evaluate the potential of three aqueous extracts of fennel seeds with different extraction conditions (pH 3, 7 and 12) as natural antimicrobial, antiviral, antioxidant and antitumor agents from the safety point of view. The three aqueous extracts were then used for evaluation of yield, total carbohydrates, protein, flavenoid and total phenolic contents. Antioxidant activity was evaluated using the DPPH• radical scavenging. The results showed that the high anti-scavenging activity was noticed for three different aqueous extracts of fennel at 2.0 mg dose comparable to other doses. In addition, the antimicrobial activity of the aqueous extracts against tested Gram positive and negative bacteria, yeast and fungi strains was determined. The extract (concentration 1.6 mg/ ml) was effective against most of the strains tested, yet not against Candid...
Leaves, seeds and seed kernels of Azadirachta indica A juss (Neem) were studied for their chemica... more Leaves, seeds and seed kernels of Azadirachta indica A juss (Neem) were studied for their chemical properties; moisture, ash, crude protein, crude lipids and total carbohydrates. GC/MS of the volatile components produced by simultaneous hydrodistillation and solvent extraction of each plant organs under investigation were carried out. GLC of the sterol and hydrocarbons fraction as well as the fatty acid fraction were studied for the plant organs. Antiviral activity of successive extractives of each of the plant organs were evaluated against Newcastle disease virus (NDV) and infectious bursal disease virus (IBDV) in culture of VERO cell and in chicken embryos.
Abstract Enterolobium cyclocarpum (EC) is an edible plant and a gum source for food industries. I... more Abstract Enterolobium cyclocarpum (EC) is an edible plant and a gum source for food industries. Its sulfated polysaccharide extract (SEC) was examined for cancer chemopreventive properties to estimate its anti-tumor activity. The modulation of carcinogen metabolism and the antioxidant activity revealed that SEC is a potent tumor anti-initiator since it inhibited cytochrome P450-1A (CYP1A) and induced carcinogen detoxification enzyme glutathione-S-transferase. SEC is also a weak scavenger for hydroxyl and peroxyl radicals. SEC was found to modulate macrophage functions into an anti-inflammatory pattern, where it enhanced macrophage proliferation and phagocytosis of fluorescein isothiocyanate-lipopolysaccharide (FITC-LPS). In addition, SEC strongly inhibited the nitric oxide (NO) generation in LPS-stimulated macrophages and induced the binding affinity of FITC–LPS to macrophages. SEC exhibited specific cytotoxicity against human hepatocellular Hep G2 carcinoma cells. SEC disturbed the cell cycle phase, as indicated by the concomitant arrest in S- and G2/M-phases that was associated with necrosis induction. A short-term initiation model for liver cancer was prepared using diethylnitrosamine (DEN) in rats. SEC inhibited the DEN-histopathological findings and reduced both CYP1A and the tumor initiation marker placental glutathione S-transferase (GSTP). Taken together, SEC could be used as an alternative gum in health food industries to provide cancer prevention in high-risk populations.
Usage of lignin and its derivatives as chemical and carbon source, i.e. in processes other than b... more Usage of lignin and its derivatives as chemical and carbon source, i.e. in processes other than burning, is one of the most active fields in renewable resource chemistry today. In this study, the synthesis of lignosulfonate (LS)-based polyurethane (PU) materials from non-toxic reagents and through environmentally friendly processes is presented. LS, modified with bio-based (glycerin-derived) cyclic carbonate moieties, was reacted with 1,6-hexamethylenediamine (HMDA) to form characteristic PU material. For mechanistic studies and reaction optimization, cyclic carbonates and 1,2-diol derivatives of vanillyl alcohol (VA), as a simplifying lignin model compound, were employed. An LS-bound cyclic carbonate can be formed in one pot without a transesterification step, which simplifies the route toward non-isocyanate lignin-based PU materials. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra showed typical linkages of cyclic carbonates and 1,2-diols on LS. Further a...
Fine fibres (fines) occur at various stages of the papermaking process. The high specific surface... more Fine fibres (fines) occur at various stages of the papermaking process. The high specific surface of fines may be of special interest in applications beyond papermaking. In the present study, foamy water suspensions of fines were freeze-dried, and in this way their porous structure was maintained. The density and porosity of these foams could be governed by varying the water content of the suspensions. The obtained matrices were highly hydrophobic because of the sizing applied during the papermaking process. Consequently, a high oil sorption capacity of the fines was observed. Up to a porosity of 98%, more than 80% of the overall volume of the foam-like material could be soaked with liquid. At higher porosities, the absorbed volume decreased. Mechanical reinforcement of the foams with poly(methyl methacrylate) (PMMA) as accomplished by dip-coating had no negative impact on the sorption behaviour. However, the performance of reinforced samples suffered from strong shrinkage upon dryi...
Fibers resulting from pulping of wood are negatively charged by nature. This charge might be reve... more Fibers resulting from pulping of wood are negatively charged by nature. This charge might be reversed by chemical modification for different applications. In this study, different options to determine the degree of substitution (DS) with cationic groups introduced using 2,3-epoxypropyltrimethylammonium chloride, a common cationization reagent, are compared. Classical analytical methods for this purpose include elemental analysis, which is unspecific, and titration, which is sensitive toward impurities and highly elaborate. These are complemented by fast and robust approaches based on infrared spectroscopy or thermogravimetric analysis. The absorption increase at 1480 cm−1 is specific for the introduced R-NMe3 and linearly correlated with the DS. For bleached Kraft pulps, cationization splits the thermal degradation of cellulose in two phases, their ratio being roughly proportional to the DS. Both methods require virtually no sample preparation. Infrared spectroscopy is particularly easy to apply and allows a quantification of pulp cationization in short time.
In this study, a chemical modification of the polysaccharides extract (E) derived from Leucaena l... more In this study, a chemical modification of the polysaccharides extract (E) derived from Leucaena leucocephala seeds was performed to prepare C-glycosidic 2-propanol derivative (PE), and its sulphated derivative (SPE). This study aimed to characterize immunomodulatory activities of the original extract and its derivatives by exploring their effects on Raw macrophage 264.7 functions and their antioxidant activity. Our results indicated that PE was an effective radical scavenger to hydroxyl, peroxyl, and superoxide anion radicals, and SPE was a peroxyl radical scavenger. PE and SPE were found to influence the macrophage functions. Both of PE and SPE enhanced the macrophage proliferation and phagocytosis of FITC-zymosan; PE inhibited nitric oxide (NO) generation and tumor necrosis factor-alpha (TNF-alpha) secretion in lipopolysaccharide (LPS)-stimulated Raw macrophage 264.7. In contrast, SPE over-induced NO generation and TNF-alpha secretion. Moreover, PE strongly inhibited the binding affinity of FITC-LPS to Raw 264.7, as indicated by flow cytometry analysis. These findings revealed that PE may act as a potent anti-inflammatory agent; however SPE may act as an inducer of macrophage functions against pathogens.
In this study, we have shown the microbial alkaline protease production by using isolated Bacillu... more In this study, we have shown the microbial alkaline protease production by using isolated Bacillus subtilis. Bacillus subtilis which produces an extracellular alkaline protease was isolated from meet surface purchased from local Egyptian markets. Maximum enzyme activity was achieved when the bacterium was grown on corn steep liquor (2.0 %, w/v) instead of soybean meal (2 %) followed by casein hydrolysate (2%, w/v) and 12 % cane sugar molasses as a carbon source at pH 10.0 and 37oC over 24 h incubation period (maximum enzyme production at 48 hr.). The enzyme has an optimum pH of around 10.0 and maintained its stability over a broad pH range between 5.0 to 12.0. Its optimum temperature is around 37 °C, and exhibited a stability of up to 50 oC.
A sequential optimization strategy, based on statistical experimental designs, was employed to en... more A sequential optimization strategy, based on statistical experimental designs, was employed to enhance the production of invertase by Lactobacillus brevis Mm-6 isolated from breast milk. First, a 2-level Plackett–Burman design was applied to screen the bioprocess parameters that significantly influence the invertase production. The second optimization step was performed using fractional factorial design in order to optimize the amounts of variables have the highest positive significant effect on the invertase production. A maximal enzyme activity of 1399 U/ml was more than five folds the activity obtained using the basal medium. Invertase was immobilized onto grafted alginate beads to improve the enzyme’s stability. Immobilization process increased the operational temperature from 30 to 60 ◦C compared to the free enzyme. The reusability test proved the durability of the grafted alginate beads for 15 cycles with retention of 100% of the immobilized enzyme activity to be more convenie...
A newly isolated moderately halophilic bacterial strain from Egyptian hyper saline source was ide... more A newly isolated moderately halophilic bacterial strain from Egyptian hyper saline source was identified as Chromohalobacter salexigens and was selected for its ability to produce extracellular levan. Different environmental and nutritional factors were optimized. These factors including initial pH, temperature, nitrogen source, sodium chloride concentration, phosphorous source in addition to the sequence incubation at optimum and cold temperature. The resulted polymer was identified by paper chromatography, NMR and FT-IR spectroscopy. Also chemical modifications (carboxymethylation and sulphation) were proceeded and the biological activity (fibrinolytic, prebiotic activity) of resulted levan and its derivatives were also determined. The highest quantity of levan (11.9 g l) was produced at pH 8, sodium chloride concentration 15%, ammonium sulphate as nitrogen source and sequence incubation at optimum followed by cold temperature. Chemically modified levan recorded high fibrinolytic ...
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment o... more Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment of various diseases. This study was designed to evaluate the potential of three aqueous extracts of fennel seeds with different extraction conditions (pH 3, 7 and 12) as natural antimicrobial, antiviral, antioxidant and antitumor agents from the safety point of view. The three aqueous extracts were then used for evaluation of yield, total carbohydrates, protein, flavenoid and total phenolic contents. Antioxidant activity was evaluated using the DPPH• radical scavenging. The results showed that the high anti-scavenging activity was noticed for three different aqueous extracts of fennel at 2.0 mg dose comparable to other doses. In addition, the antimicrobial activity of the aqueous extracts against tested Gram positive and negative bacteria, yeast and fungi strains was determined. The extract (concentration 1.6 mg/ ml) was effective against most of the strains tested, yet not against Candid...
Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment o... more Foeniculum vulgare (fennel) has been widely used in Egyptian traditional medicine for treatment of various diseases. This study was designed to evaluate the potential of three aqueous extracts of fennel seeds with different extraction conditions (pH 3, 7 and 12) as natural antimicrobial, antiviral, antioxidant and antitumor agents from the safety point of view. The three aqueous extracts were then used for evaluation of yield, total carbohydrates, protein, flavenoid and total phenolic contents. Antioxidant activity was evaluated using the DPPH• radical scavenging. The results showed that the high anti-scavenging activity was noticed for three different aqueous extracts of fennel at 2.0 mg dose comparable to other doses. In addition, the antimicrobial activity of the aqueous extracts against tested Gram positive and negative bacteria, yeast and fungi strains was determined. The extract (concentration 1.6 mg/ ml) was effective against most of the strains tested, yet not against Candid...
Leaves, seeds and seed kernels of Azadirachta indica A juss (Neem) were studied for their chemica... more Leaves, seeds and seed kernels of Azadirachta indica A juss (Neem) were studied for their chemical properties; moisture, ash, crude protein, crude lipids and total carbohydrates. GC/MS of the volatile components produced by simultaneous hydrodistillation and solvent extraction of each plant organs under investigation were carried out. GLC of the sterol and hydrocarbons fraction as well as the fatty acid fraction were studied for the plant organs. Antiviral activity of successive extractives of each of the plant organs were evaluated against Newcastle disease virus (NDV) and infectious bursal disease virus (IBDV) in culture of VERO cell and in chicken embryos.
Abstract Enterolobium cyclocarpum (EC) is an edible plant and a gum source for food industries. I... more Abstract Enterolobium cyclocarpum (EC) is an edible plant and a gum source for food industries. Its sulfated polysaccharide extract (SEC) was examined for cancer chemopreventive properties to estimate its anti-tumor activity. The modulation of carcinogen metabolism and the antioxidant activity revealed that SEC is a potent tumor anti-initiator since it inhibited cytochrome P450-1A (CYP1A) and induced carcinogen detoxification enzyme glutathione-S-transferase. SEC is also a weak scavenger for hydroxyl and peroxyl radicals. SEC was found to modulate macrophage functions into an anti-inflammatory pattern, where it enhanced macrophage proliferation and phagocytosis of fluorescein isothiocyanate-lipopolysaccharide (FITC-LPS). In addition, SEC strongly inhibited the nitric oxide (NO) generation in LPS-stimulated macrophages and induced the binding affinity of FITC–LPS to macrophages. SEC exhibited specific cytotoxicity against human hepatocellular Hep G2 carcinoma cells. SEC disturbed the cell cycle phase, as indicated by the concomitant arrest in S- and G2/M-phases that was associated with necrosis induction. A short-term initiation model for liver cancer was prepared using diethylnitrosamine (DEN) in rats. SEC inhibited the DEN-histopathological findings and reduced both CYP1A and the tumor initiation marker placental glutathione S-transferase (GSTP). Taken together, SEC could be used as an alternative gum in health food industries to provide cancer prevention in high-risk populations.
Usage of lignin and its derivatives as chemical and carbon source, i.e. in processes other than b... more Usage of lignin and its derivatives as chemical and carbon source, i.e. in processes other than burning, is one of the most active fields in renewable resource chemistry today. In this study, the synthesis of lignosulfonate (LS)-based polyurethane (PU) materials from non-toxic reagents and through environmentally friendly processes is presented. LS, modified with bio-based (glycerin-derived) cyclic carbonate moieties, was reacted with 1,6-hexamethylenediamine (HMDA) to form characteristic PU material. For mechanistic studies and reaction optimization, cyclic carbonates and 1,2-diol derivatives of vanillyl alcohol (VA), as a simplifying lignin model compound, were employed. An LS-bound cyclic carbonate can be formed in one pot without a transesterification step, which simplifies the route toward non-isocyanate lignin-based PU materials. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra showed typical linkages of cyclic carbonates and 1,2-diols on LS. Further a...
Fine fibres (fines) occur at various stages of the papermaking process. The high specific surface... more Fine fibres (fines) occur at various stages of the papermaking process. The high specific surface of fines may be of special interest in applications beyond papermaking. In the present study, foamy water suspensions of fines were freeze-dried, and in this way their porous structure was maintained. The density and porosity of these foams could be governed by varying the water content of the suspensions. The obtained matrices were highly hydrophobic because of the sizing applied during the papermaking process. Consequently, a high oil sorption capacity of the fines was observed. Up to a porosity of 98%, more than 80% of the overall volume of the foam-like material could be soaked with liquid. At higher porosities, the absorbed volume decreased. Mechanical reinforcement of the foams with poly(methyl methacrylate) (PMMA) as accomplished by dip-coating had no negative impact on the sorption behaviour. However, the performance of reinforced samples suffered from strong shrinkage upon dryi...
Fibers resulting from pulping of wood are negatively charged by nature. This charge might be reve... more Fibers resulting from pulping of wood are negatively charged by nature. This charge might be reversed by chemical modification for different applications. In this study, different options to determine the degree of substitution (DS) with cationic groups introduced using 2,3-epoxypropyltrimethylammonium chloride, a common cationization reagent, are compared. Classical analytical methods for this purpose include elemental analysis, which is unspecific, and titration, which is sensitive toward impurities and highly elaborate. These are complemented by fast and robust approaches based on infrared spectroscopy or thermogravimetric analysis. The absorption increase at 1480 cm−1 is specific for the introduced R-NMe3 and linearly correlated with the DS. For bleached Kraft pulps, cationization splits the thermal degradation of cellulose in two phases, their ratio being roughly proportional to the DS. Both methods require virtually no sample preparation. Infrared spectroscopy is particularly easy to apply and allows a quantification of pulp cationization in short time.
In this study, a chemical modification of the polysaccharides extract (E) derived from Leucaena l... more In this study, a chemical modification of the polysaccharides extract (E) derived from Leucaena leucocephala seeds was performed to prepare C-glycosidic 2-propanol derivative (PE), and its sulphated derivative (SPE). This study aimed to characterize immunomodulatory activities of the original extract and its derivatives by exploring their effects on Raw macrophage 264.7 functions and their antioxidant activity. Our results indicated that PE was an effective radical scavenger to hydroxyl, peroxyl, and superoxide anion radicals, and SPE was a peroxyl radical scavenger. PE and SPE were found to influence the macrophage functions. Both of PE and SPE enhanced the macrophage proliferation and phagocytosis of FITC-zymosan; PE inhibited nitric oxide (NO) generation and tumor necrosis factor-alpha (TNF-alpha) secretion in lipopolysaccharide (LPS)-stimulated Raw macrophage 264.7. In contrast, SPE over-induced NO generation and TNF-alpha secretion. Moreover, PE strongly inhibited the binding affinity of FITC-LPS to Raw 264.7, as indicated by flow cytometry analysis. These findings revealed that PE may act as a potent anti-inflammatory agent; however SPE may act as an inducer of macrophage functions against pathogens.
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