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Production and prebiotic activity of exopolysaccharides derived from some probiotics
Magdel-Din M Hussein, Mohamed F Ghaly, Mona Y Osman, Al Shimaa G Shalaby, Mohamed MI Helal
January-April 2015, 14(1):1-9
Objective The aim of this study was to focus on exopolysaccharides (EPSs) produced by Lactobacillus delbrueckii bulgaricus, Lactobacillus helveticus or Lactobacillus casei and their use as a prebiotic for Lactobacillus reuteri, Lactobacillus rhamnosus, Lactobacillus acidophilus or Bifidobacterium bifidum. Materials and methods Optimization of culture conditions using different carbon and nitrogen sources and different temperature, pH and incubation periods for maximum EPS production was studied. Results and conclusion It was found that the best conditions were as follows: the use of sucrose (20%) instead of glucose in MRS medium, incubation at pH 7.0 and temperature 37°C for 72 h incubation under anaerobic conditions to give the highest EPS yield; a yield of 13.99 g/l was recorded in case of L. helveticus when grown on the aforementioned optimized conditions. It was found that L. delbrueckii bulgaricus EPS has the highest prebiotic indices (I), varying from 7.9 to 10.1. In contrast, L. helveticus and L. casei EPSs have the lowest prebiotic indices (I), varying from 1.4 to 2.4.
  7 3,039 553
Levofloxacin: formulation and in-vitro evaluation of alginate and chitosan nanospheres
Ramadoss Arun Balaji, Sathya Raghunathan, Radhakrishnan Revathy
January-April 2015, 14(1):30-35
Background and objectives Levofloxacin, the active l-isomer of ofloxacin, is a widely used fluoroquinolone, with activity against bacteria that causes respiratory, skin, and genitourinary tract infections, (-)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido benzoxazine-6-carboxylic acid hemihydrates. It is a new quinolone antimicrobial agent that exhibits broad-spectrum in-vitro bactericidal activities against gram-positive and gram-negative aerobes. The aim of this study was to formulate sodium alginate nanospheres containing levofloxacin and evaluate its physiochemical properties, exploring alternative routes of administration, such as nanoparticle to develop a targeted drug delivery system and to act locally on the organ of infection with enriched therapeutic efficacy. Materials and methods Sodium alginate and calcium chloride solutions were prepared. A constant volume (20 μl) of levofloxacin solution was incorporated into the sodium alginate solution, and then the same method was followed for the preparation of hybrid chitosan-alginate nanoparticles. In-vitro release study was carried out by dialysis membrane for 7 h in the physiological fluid (pH 7.4 phosphate buffer solution). Morphology and structure characterization of nanoparticles were investigated by field emission scanning electron microscope and Fourier transform infrared spectra, zeta potential, X-ray diffraction, particle size analysis, respectively. Results and conclusion This paper reports the possibility to entrap lipophilic levofloxacin within chitosan/alginate (CS/ALG) nanoparticles using a very simple ionotropic pregelation technique; strong electrostatic interactions exist in the nanoparticles. The nanoparticles with a diameter of 25-55 nm were obtained at the optimal mass range of sodium alginate: calcium chloride:chitosan in the meta acid environment. The delivery behavior of levofloxacin from nanoparticles was studied. Levofloxacin released from chitosan-alginate nanoparticles was 71% at pH 7.4 within 7 h. The release profile was characterized by an initial burst effect in phosphate buffer solution, followed by a continuous and controlled release phase. The drug release mechanism from polymer also offers an interesting potential for the delivery of lipophilic compound.
  6 3,360 600
Synthesis, antifungal activity, and molecular docking study of some novel highly substituted 3-indolylthiophene derivatives
Heba M Abo-Salem, Eslam R El-Sawy, Ahmed Fathy, Adel H Mandour
July-December 2014, 13(2):71-86
Background and objectives The currently available antifungal drugs have the limitations of toxicity, potential drug interaction with other drugs, insufficient pharmacokinetics properties, and development of resistance. Thus, development of new antifungal agents with less toxicity is urgently required. The present work aimed to synthesize new 3-indolylthiophene derivatives and evaluate their antifungal activity by studying their molecular docking. Materials and methods New series of thiadiazoles 4a-c , morpholinyl-acetamides 6a-c , 4-methylpiperazinylacetamides 7a-c , thiazolidines 10a-c , azetidines 12a-c - 13a-c , sulfonamides 14a-c - 15a-c , benzamides 16a-c , pyrrolidines 17a-c , succinamic acids 18a-c , acetamides 19a-c , thieno(2,3-c)pyridines 20a-c , thieno(2,3-e)-1,2,4-triazolo(1,5-c)pyrimidines 23a-c , thieno(2,3-d) pyrimidines 24a-c - 26a-c , and thieno(2,3-b)pyridines 27a-c derivatives incorporated into N-substituted 3-indolylthiophenes were prepared by an initial reaction of 2-amino-4-(N-substituted-1H-indol-3-yl)thiophene-3-carbonitriles 1a-c with different reagents. The antifungal activity of the newly synthesized compounds was evaluated against two strains of fungi, namely, Candida albicans (ATCC-10231) and Aspergillus niger (ATCC-10535). However, the mode of action of the most promising antifungal compounds was assessed by docking with cytochrome P450 14 α-sterol demethylase (CYP51) (PDB ID: 1EA1). Results and conclusion Compound 4a showed good inhibitory activity against both C. albicans (ATCC-10231) and A. niger ( ATCC-10535), with minimum inhibitory concentrations values of 9 and 36 μg/disk, respectively, compared with fluconazole, with minimum inhibitory concentrations values of 8 and 34 μg/disk. Docking results showed that compound 4a had the highest docking score, with a binding energy of −30.25 kJ/mol, which is in agreement with the experimental activity value.
  5 2,318 3,995
Improvement in bacterial cellulose production using Gluconacetobacter xylinus ATCC 10245 and characterization of the cellulose pellicles produced
Nagwa A Atwa, Ahmed I El-Diwany, Houssni El-Saied, Altaf H Basta
May-August 2015, 14(2):123-129
Aim This paper deals with the improvement in bacterial cellulose (BC) production by Gluconacetobacter xylinus ATCC 10245 cultivated under shaking condition. Materials and methods The study was performed using two different approaches. First, through the addition of some thickening agents to the fermentation medium; second, by applying a two-stage fermentation process in which cells of G. xylinus were grown under two successive static and shaking conditions. During the first fermentation stage, the experimental microorganism was cultivated under static condition to produce thick, leather-like, white BC pellicles on which the bacterial cells were firmly adhered. However, during the second fermentation stage, these pellicles were reused to inoculate fresh, more economic medium, and incubated under shaking condition. Results The results showed that the addition of sodium alginate at a concentration of 0.4 g/l resulted in a BC production of 8.25 g/l compared with only 1.7 g/l obtained using the control medium without thickeners under similar shaking condition. The second method resulted in a substantial increase in the produced BC pellicle up to about 16.9 g/l. Further increase in the weight of the BC gels was obtained by adopting a repeated batch cultivation method during the second fermentation stage. After seven successive repeated batches, which extended for 56 days, the total BC mass reached 81.25 g/l. The properties of some BC pellicles were studied using thermogravimetric analyses and then compared with those of cotton linter. Conclusion The results showed that these two methods are very promising for BC production on a large scale.
  4 1,759 312
Comparative studies of free and immobilized phytase, produced by Penicillium purpurogenu GE1, using grafted alginate/carrageenan beads
Ghada EA Awad, Mona A Esawy, Eman W El-Gammal, Hanan Mostafa Ahmed, Magdy M Elnashar, Nagwa A Atwa
May-August 2015, 14(2):87-93
Aim The aim of the study was to immobilize the phytase enzyme produced by Penicillium purpurogenu GE1 on grafted alginate/carrageenan beads and study the properties of the immobilized enzyme in comparison with free ones. Materials and methods The immobilization conditions were first optimized and then the optimum conditions of temperature and pH for the maximum activity of the immobilized and free enzyme were studied and compared. The stabilities of both immobilized and free phytase at moderate and low temperatures of 50 and 4°C, as well as their stability at the acidic pH of 4, were also studied. Finally, the activity of the immobilized enzyme was monitored over 20 successive repeated batches. Results The maximum loading capacity was obtained after 20 h at the enzyme/acetate buffer dilution ratio of 1 : 2. The optimum temperature and pH of the immobilized enzyme, as compared with free state, were found to have shifted from 37 to 45°C and from pH 5.5 to 4, respectively. Moreover, the results also proved that when phytase in both immobilized and free states was subjected to an acidic pH of 4 for 45 min, or to a moderately high temperature of 50°C for 60 min, the activity of the former remained stable, whereas that of the latter showed substantial losses. In contrast, at the refrigerator shelf temperature of 4°C, dry and wet immobilized forms retained 100% activity for 12 weeks, whereas that of the free enzyme was completely lost within a shorter period of 4 weeks. Furthermore, the activity of the phytase enzyme immobilized on gel beads was maintained at the 100% level for more than 12 repeated batch utilizations of the beads. Conclusion The results revealed that the physiological parameters of the immobilized enzyme were greatly improved compared with the free state. Further, the activity of the phytase enzyme immobilized on gel beads was maintained at the 100% level for more than 12 repeated batch cultivations of the beads.
  4 1,463 280
Synthesis of certain N-aralkyl-N-(1-((cyclohexylamino)methyl)cyclohexyl)benzenamines and benzamides and their anticonvulsant and analgesic potential
Mohammed N Aboul-Enein, Aida El-Azzouny, Fatma Ragab, Mohammed S Abdel-Maksoud, Yousreya Maklad
January-June 2014, 13(1):1-12
Background and objectives Epilepsy is a central nervous system disorder, affecting about 1% of the world's population, and is mostly prevalent in developing nations. In addition, many geminally disubstituted cyclohexane derivatives have proven to have anticonvulsant and analgesic activities. The aim of this study was to synthesize a new series of N-aralkyl-N-(1-((cyclohexylamino)methyl)cyclohexyl)benzenamines, 6a-h, and N-(1-((cyclohexylamino)methyl)cyclohexyl)-N-phenyl-substituted benzamides, 8a-g, for the purpose of evaluating their anticonvulsant and analgesic potential. In addition, the in-silico properties of the newly synthesized compounds have been discussed. Materials and methods Starting from 1-(N-phenylbenzamido and 4-substituted benzamido)cyclohexane carboxylic acids 3a-g, a new series of N-aralkyl-N-(1-((cyclohexylamino)methyl)cyclohexyl)benzenamines, 6a-h, was synthesized through formation of the corresponding methyl esters 4a-g, which underwent complete reduction of both the ester and the tertiary amidic carbonyl groups to afford the desired amino alcohols, 5a-g. Condensation of the corresponding mesylate esters with cyclohexylamine gave the target diamines 6a-g. Also, the alcohols 7a-g were achieved from 3a-g using NaBH 4 without affecting the amidic group, followed by preparation of the corresponding intermediate mesylate esters, which reacted with cyclohexylamine to yield the benzamidecyclohexyl amines 8a-g. The anticonvulsant and analgesic properties of 6a-h and 8a-h were studied using the pentylenetetrazole screening test and the hot-plate technique, respectively. Results and conclusion The results of the present study revealed that the most active compounds that exhibited remarkable 100% protection in mice were 6b , 6d , 6e , 8a, 8b , 8f and 8h, compared with diphenylhydantoin sodium and valproic acid, which were used as reference drugs. Both N-aralkyl-N-(1-((cyclohexyl amino)methyl)cyclohexyl)benzenamine and N-(1-((cyclohexylamino)methyl)cyclohexyl)-N-phenyl-substituted benzamide series, 6a-h and 8a-h, displayed significant antinociceptive effects. However, the 6a-h series showed higher potential than the 8a-h one. The results of the in-silico studies for the newly synthesized compounds showed that compounds 6c , 6e , 6h , 8e , 8f and 8h exhibit low mutagenic, tumorigenic, reproductive and medium irritant effect, as well as good drug-likeness and drug score.
  4 2,033 250
Detection of Neisseria meningitidis DNA in blood samples using direct-PCR test
Ahmed M Mora, Nour M Abdel-Kader, Soheir S Maklad
July-December 2013, 12(2):115-119
Background Meningococcal disease caused by Neisseria meningitidis is a widely distributed complex human disease affecting all age categories. Successful and effective treatment of patients with this disease depends on precise and early diagnosis of the disease. Objective The aim of this study was to evaluate the possible use of direct PCR (D-PCR) for the detection and amplification of N. meningitidis DNA in blood samples compared with the conventional PCR (C-PCR) method, which needs bacterial culture and DNA extraction. Materials and methods Specific primers on the basis of the 16S rDNA of N. meningitidis were used for the amplification of 600 bp DNA fragment. Two strategies were followed: D-PCR, which relies on amplification of DNA directly in blood without DNA extraction using the KAPA Blood PCR Kit, and the C-PCR, which relies on the extraction of bacterial DNA using the Qiagen QiAmp DNA Mini Kit. The following blood samples were included in each strategy: A blood sample with bacterial cerebrospinal meningitis confirmed by blood culture, a normal blood sample seeded with N. meningitidis ATCC (13090) reference strain as positive control for the standardization of the PCR procedure, a normal blood sample as a negative control, and an internal negative control test sample (H 2 O). Results Both D-PCR and C-PCR tests gave the expected amplified DNA fragment of 600 bp on agarose gel electrophoresis of both patients' blood sample and N. meningitidis seeded normal blood sample, whereas no amplified products were detected when both tests were performed on normal blood sample or the internal negative H 2 O control. Conclusion Direct blood PCR assay could be a possible easy, rapid, nonexpensive, and specific method for the detection of meningococci in blood samples, particularly in situations in which culture is difficult because of previous treatment, and also could facilitate the large-scale screening of various medical conditions.
  3 2,180 324
Novel keratinase from marine Nocardiopsis dassonvillei NRC2aza exhibiting remarkable hide dehairing
Azza M Abdel-Fattah
July-December 2013, 12(2):142-147
Background The isolation of the locally marine Nocardiopsis dassonvillei NRC2aza was characterized by the exceptional dehairing properties of its subtilisin-like keratinase. Objectives The aim of this work was to extract keratinase enzyme from the marine Nocardiopsis dassonvillei NRC2aza to be an alternative to sodium sulphide, which is the major pollutant from tanneries. Its unique nonactivity on collagen enhances its industrial potential. Material and methods Fermentation of the marine isolate Nocardiopsis dassonvillei NRC2aza on whole-feather medium was performed for keratrinase enzyme production. Extraction of the enzyme was carried out by solid-state fermentation (SSF). Results and conclusion Nocardiopsis dassonvillei NRC2aza have excellent characteristics of crude keratinase, producing 1680 U/ml in a shaking submerged culture (SmF) and 19 760 U/g using SSF after 4 days at pH 7. The effect of inoculum concentration on SSF was studied, whereby higher concentrations (150-200%) lowered the activity. Fractional precipitation of the enzyme by ammonium sulphate produced four fractions, of which 70% was the most active and produced remarkable hide dehairing. A new locally isolated Streptomyces spp. from marine ecosystem produced a highly active keratinase enzyme that exhibits remarkable hide dehairing.
  3 3,890 313
Chemical composition and antimicrobial activity of volatile constituents from the roots, leaves, and seeds of Arctium lappa L. (Asteraceae) grown in Egypt
Elsayed A Aboutabl, Mona E El-Tantawy, Manal M Shams
July-December 2013, 12(2):173-176
Background and objective As no literature was traced dealing with the volatile constituents of the leaves or the seeds of Arctium lappa L., it was deemed of interest to carry out a gas chromatography/mass spectrometry (GC/MS) analysis and antimicrobial activity study of the volatile constituents of roots, leaves, and seeds of the plant grown in Egypt. Materials and methods The volatile constituents of the roots, leaves, and seeds were analyzed by GC/MS. The antimicrobial activity was tested using the agar well diffusion technique. Results and conclusion GC/MS of the volatile constituents from the leaves showed 19 identified compounds, the major being caryophyllene oxide (54.2%), followed by β-elemene (6.2%) and β-costol (4.0%). Analysis of the volatile constituents of the roots revealed 14 identified compounds, the major being caryophyllene oxide (51%), followed by aromadendrene (16%) and isoaromadendrene epoxide (6.4%). Analysis of the volatile constituents of the seeds revealed 22 identified compounds, the major being E-citral (28.8%), followed by geraniol (20.3%) and Z-citral (9.5%). The volatile constituents of the leaves and roots exhibited moderate antimicrobial activity against bacteria and significant antifungal activity, in comparison with the standards used, whereas the volatile constituents of the seeds showed moderate antimicrobial activity against bacteria and fungi.
  3 5,251 404
Modulation effects of quercetin against copper oxide nanoparticles-induced liver toxicity in rats
Azza F Arafa, Hassan Z Ghanem, Mahmoud S Soliman, Emad EL-Meligy
May-August 2017, 16(2):78-86
Background and objectives Despite the several benefits of nanotechnology, studies indicated that certain nanoparticles (NPs) may cause adverse effects because of their minute size and unique properties. The aim of this study is to investigate the role of quercetin (que) in attenuating toxicity by copper oxide (CuO) NPs in rat liver. Materials and methods The effect of CuO-NPs on the liver was induced by two injections of CuO-NPs (size >20 nm) at the dose 3 mg/kg and 50 mg/kg intraperitoneally in different groups of female rats for 7 days. The effects of NPs were tested by evaluating liver function enzymes: alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase; antioxidant biomarkers: nitric oxide, catalase activity, reduced glutathione, and total antioxidant capacity; DNA damage as shown by comet assay; and histopathological examination of hepatic tissue. Flavonoids que was administered orally to intoxicated rats at the dose of 200 mg/kg for 30 consecutive days. Results and conclusion The present results indicated significant depletion in serum hepatic enzyme activities and improvement in the cellular antioxidant status of CuO-NPs-intoxicated rats after administration of que. Histopathological examination of hepatic tissue treated with que confirmed the previous biochemical results, which showed normal architecture of hepatic tissues. However, treatment of intoxicated rats with que led to a significant reduction in the DNA damage, tail length, and tail moment. Oxidative stress could be considered to play a key role in liver toxicity by CuO-NPs. This research also showed that que is an effective free-radical quencher and could represent a potential valid therapeutic for hepatotoxicity.
  3 1,696 301
Evaluation of Egyptian pomegranate cultivars for antioxidant activity, phenolic and flavonoid contents
Ahmed M. A. Souleman, Gamil E Ibrahim
September-December 2016, 15(3):143-149
Aim The aim of the present study was to evaluate total phenolic and flavonoid contents as well as antioxidant activity of the peel, juice and seed extracts of pomegranate fruit from different Egyptian cultivars. The selected cultivar was subjected for evaluation of the effect of peel homogenate on volatile compounds in juice supplemented with this homogenate. Background Pomegranate fruit is a rich source of natural antioxidants; it has wide applications in food and pharmaceutical industry. Materials and methods Five cultivars of Egyptian pomegranate were subjected to a comparative study of phenolic and flavonoid contents as well as its antioxidant activity. The phenolic compounds were determined through high-performance liquid chromatography, and the volatile compounds of selected cultivar peel were added to juice through gas chromatography and gas chromatography–mass spectrometry. Results While the total phenolic content varied between 5.21 mg gallic acid equivalent/g in PG4 fruit juice and 17.24 mg gallic acid equivalent/g in PG1 peel, the total flavonoid content ranged from 9.64 in PG2 juice to 34.28 mg rutin/g in the peel of PG1. All peel, juice and seeds extracts exhibited high antioxidant activities, evaluated using 1,1’-diphenyl-2-picrylhydrazyl and β-carotene assays. Gallic acid, chlorogenic acid and caffeic acid were the predominant phenolic compounds of the pomegranate cultivars. A total of 17 volatile compounds were identified, including six monoterpenes, three monoterpenoids, three aldehydes, three esters, and two alcohols. Conclusion Peel, juice and seed of Egyptian pomegranate cultivars contain significant amounts of phenolics and flavonoids contents. However, the peel contains higher contents compared with juice and seeds. Peel homogenate of the selected cultivar showed a remarkable effect on volatile compounds when used for fortification of the pomegranate juice.
  3 1,840 575
Statistical optimization of L-asparaginase production by using Fusarium solani
Abeer A El-Hadi, Heba A El-Refai, Mona S Shafei, Rania Zaki, Hanan Mostafa
January-April 2017, 16(1):16-23
Background and objective The enzyme l-asparaginase is important as a therapeutic agent in the treatment of acute lymphocytic leukemia. It has been observed that microorganisms such as yeast and filamentous fungi such as Aspergillus spp., Penicillium spp., and Fusarium spp. are commonly produced asparaginases with fewer adverse effects. Fusarium solani was selected to be the most potent microbial isolate for l-asparaginase production. The factors controlling l-asparaginase production, such as containing media, were implemented to increase the yield of l-asparaginase. Statistical experimental design such as the Plackett–Burman enables finding out the most effective factors that increase the yield of l-asparaginase. Materials and methods Aspergillus rubber, Aspergillus terreus, Epico niger, Penicillium cyclopium, and F. solani were chosen for screening the l-asparaginase activity using phenol red – a pH indicator. l-Asparagine and the modified Czapek Dox media were tested for the production of l-asparaginase from F. solani under different incubation times. To optimize l-asparaginase production by using F. solani, the combined effect of seven variables (l-asparagine, sucrose, NaNo3, K2HPO4, MgSO4, KCl, and time) were assessed using the central composite design. Results and conclusion All the four fungal strains screened for l-asparaginase activity showed positive results in the rapid plate assay method. The medium employed contained asparagine with phenol red, and after incubation, pink zones around the colonies were observed. F. solani was a potential source for a high yield of l-asparaginase enzyme and high substrate specificity. Modified Czapek medium II was the most suitable for l-asparaginase, showing an activity of 121 U/ml. The result on l-asparaginase activity according to the screening Plackett–Burman experiments gives a medium composed of the following (g/l): sucrose (1); l-asparagine (0.5); KH2PO4. (0.75), MgSO4 (0.7); H2O (0.72); KCl (0.72); (NH4)2SO4 (11.7) at an incubation time of 3 days. For further investigation, x1 K2HPO4, x2 sucrose, and x3 time were found to be the most significant variables affecting l-asparaginase activity. The second optimization step was to identify optimal values of the three factors that bring about maximum l-asparaginase activity, using the central composite designed experiment. The results showed that K2HPO4 (2.5 g/l), sucrose (4 g/l), and the time (8 days) were critical in the production of l-asparaginase.
  2 1,696 291
Isolation and microbiological identification of bacterial contaminants in food and household surfaces: How to deal safely
Amal S Othman
January-April 2015, 14(1):50-55
Objective This study investigates and reveals the relationship between pathogenic bacteria in some types of food and that present in different household sites (kitchens) and determines an effective disinfecting method to eliminate bacteria from common kitchen locations, some of which could be harmful or pathogenic. Materials and methods A total of 90 samples were collected; 85 samples were taken from different sites from five home kitchens and five samples were collected from different types of food. Samples were obtained (before and after disinfection) from kitchen towels, cooking gas stove knobs, refrigerator handles, water taps, and kitchen sponges used for washing utensils by using sterile cotton swabs. Bacteria were identified according to the conventional biochemical methods. DNA fragmentation was done to show the effect of disinfectants on the most common bacteria. Results and conclusion Escherichia coli , Klebsiella spp., and Staphylococcus aureus were the most abundant bacteria in the isolates. After disinfection using disinfectants containing sodium perborate and sodium silicate (detergent), sodium hypochlorite (Clorox), 5% amphoteric surfactant and chlorine (dishwashing powder), and Dettol, the samples were free of bacterial contamination. There was also a correlation between food contamination and bacteria isolated from the kitchens. As E. coli was the most highly abundant pathogen in the kitchen and was removed by the tested disinfectants, it was chosen for DNA fragmentation assay to examine the effect of the disinfectants on the bacterial DNA. Kitchen towels, cooking gas stove knobs, refrigerator handles, water taps, and kitchen sponges are the most common sites in kitchens that transmit pathogenic bacteria. They must be disinfected routinely after preparing food.
  2 16,124 1,312
Production and partial characterization of collagenase from marine Nocardiopsis dassonvillei NRC2aza using chitin wastes
Azza M Abdel-Fattah
July-December 2013, 12(2):109-114
Background The marine ecosystem has generated considerable interest for the isolation of new microorganisms, especially Streptomyces spp. It is considered a cheaper source of precious enzymes such as collagenase. Objective This study aimed to produce new collagenase enzymes from the locally isolated marine Streptomyces spp. grown on marine wastes for application in industrial fields. Materials and methods The marine isolate was identified as Nocardiopsis dassonvillei NRC2aza by 16S rDNA sequencing. N. dassonvillei NRC2aza was grown on basal medium composed of whole chitin wastes as the sole C and N source for the production of collagenase enzyme. Extraction of the enzyme was performed to study its characteristics. Results and conclusion Maximum collagenase activity (240 U/ml) was obtained after 6 days of incubation in shaken liquid cultures when whole chitin wastes (shrimp and crab wastes) were used as the sole nitrogen and carbon source. A N. dassonvillei NRC2aza isolate was shown to produce significant amounts of collagenase, reaching 1872 U/g, under solid-state fermentation using a mixture of 10 g chitin waste and 2 g of feather. Successive ammonium sulfate fractionation of N. dassonvillei NRC2aza growth extract produced a group of collagenases with different molecular weights. The 80% enzyme fraction was the most active and possessed the highest collagenase activity (1106.66 U/f), reaching about 3.8-fold that of the culture filtrate. The optimum pH and temperature were 8 and 55°C, respectively, and the enzyme was stable at pH range of 6-8. The collagenase exhibited heat stability for 60 min at 50°C. Therefore, collagenases can be applied in food industry as tenderizers of red meat and in fur and hide tanning to ensure uniform dyeing of leather.
  2 2,869 1,542
Estimation of total phenolic, tannins, and flavonoid contents and antioxidant activity of Cedrus deodara heart wood extracts
Sourabh Jain, Aakanchha Jain, Sanjay Jain, Neelesh Malviya, Vikas Jain, Dharmendar Kumar
January-April 2015, 14(1):10-14
Purpose The present study was investigated to determine in-vitro antioxidant activity and total phenolic, total flavonoids, and total tannins contents of extracts of Cedrus deodara heart wood. Materials and methods Antioxidant activity of aqueous and alcoholic extract of C. deodara heart wood was evaluated against 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picryl hydrazyl (DPPH), and hydroxyl radical-scavenging activity models. Total flavonoids, tannins, and phenolic content of C. deodara were also determined. Results and conclusion Among both extracts, aqueous extract showed the highest total phenolic contents (23.97 μg/g of gallic acid equivalent/g of extract). In DPPH, superoxide anion, and ABTS scavenging test, the IC 50 (μg/ml) value of aqueous and alcoholic extract was 61.89, 75.79, 87.76, 121.55, 115.29, and 122.42, respectively. Hence, the above evidences suggest that C. deodara heart wood is a potential source of natural antioxidant and can be used to prevent diseases associated with free radicals.
  2 3,383 453
Synthesis, cytotoxic, proapoptotic evaluation, and molecular docking study of some new N-substituted sulfonyl-3-indolyl heterocycles
Eslam R El-Sawy, Heba M Abo-Salem, Shaymaa M Yahya, Manal S Ebaid, Adel H Mandour
January-April 2015, 14(1):15-29
Background and objectives Apoptosis, also called programmed cell death, is a fundamental biological phenomenon that plays a crucial role in processes such as immune regulation, embryogenesis, and general tissue homeostasis. B-cell lymphocyte/leukemia-2 (BCL-2) family members are key regulators of apoptosis. The ability of the indole derivative to disrupt microtubule assembly and induce G2/M arrest, polyploidy, and apoptosis through mitochondrial pathways in COLO 205 cell has been reported; in addition, it reduced the levels of procaspase-3, procaspase-9, BCL-xL, and BCL-2 gene. The aim of this study is to describe the synthesis of some new N-substituted sulfonyl-3-indolyl heterocycles and to study their cytotoxic and proapoptotic effects. In addition, a molecular docking study of the most biologically active compounds against the BCL-2 protein is discussed. Materials and methods A new series of triazolopyridines 3a-c , diaminopyridines 4a-c , acetamides 5a-c , triazolo[1,5-a]pyridines 6a-c-8a-c , pyrido[1,2-b][1,2,4]triazines 9a-c , 10a-c , pyrazoles 11a-c, 12a-c , and pyrimidine derivatives 13a-c-15a-c were prepared by an initial reaction of 2-((N-substituted sulfonyl-1H-indol-3-yl)methylene) malononitriles 2a-c with different reagents. The newly synthesized compounds were tested for their cytotoxic activity against the HepG2 cell line. The compounds that showed promising IC 50 values were chosen for the study of their proapoptotic effect on the BCL-2 gene, which is an antiapoptotic factor, and they significantly inhibited the expression levels of the BCL-2 gene. The binding mode of the most promising proapoptotic compounds was assessed by docking studies with the CHIMAERIC BCL2-XL protein (PDB ID: 2W3L). Results and conclusion From the data obtained, the most active compounds against the HepG2 cancer cell line were in the descending order of 10b>4c>10a>10c , whereas compounds 3c , 6c , 9c , 4b , and 5c showed moderate to slight growth inhibition. Compounds 4c , 5c , 9c , 10a , 10b , and 10c significantly inhibited the expression levels of the BCL-2 gene. Docking results showed that compounds 5c and 9c showed good fitting within the pocket site of the protein molecular surface and had a minimum binding energy of −20.29 and −18.98 kJ/mol, respectively, in comparison with the co-crystallized ligand, which is in agreement with the experimental result of a proapoptotic effect.
  2 1,719 302
Characterization of heavy metal and antibiotic-resistant bacteria isolated from polluted localities in Egypt
Saad A Moghannem, Bahgat M Refaat, Gamal M El-Sherbiny, Mohamed H El-Sayed, Islam A Elsehemy, Mohamed H Kalaba
September-December 2015, 14(3):158-165
Objective The aim of this study was to isolate and identify heavy metal-resistant and antibiotics-resistant bacteria from contaminated samples (wastewater and soil) collected from different industrial areas in Egypt and determine their role in heavy metal removing. Materials and methods Samples were collected from Helwan and 10th of Ramadan city areas and enriched in culture broth containing 200, 100, and 10 ppm of arsenic (As), lead (Pb), and cadmium (Cd) as AsHNa 2 O 4·H 2 O, Pb(NO 3 ) 2 , and CdSO 4 , respectively. The highly resistant isolate (ST6) was selected and identified biochemically and also subjected to 16S rDNA sequencing. The growth parameters were optimized and the maximum tolerable concentration of the respective metals as well as the antibiotic resistance was determined. Result and conclusion After enrichment culture we isolated and purified 20 bacterial isolates resistant to the respective heavy metals As, Pb, and Cd. The morphological, biochemical, and phylogenetical characteristics of the most resistant bacterial isolates (ST6) were studied. The results showed that this isolate belongs to the species Pseudomonas stutzeri. The optimum temperature was 35°C, whereas the optimum pH was in the range of 6-7. Maximum tolerable concentration values for As, Pb, and Cd were 3500, 1750, and 50 ppm, respectively. Also, the isolate ST6 showed resistance against different antibiotics. The metal removal ability was 42.5, 57.1, and 52.9% of As, Pb, and Cd, respectively. It was concluded that the ST6 isolate was resistant and removed high concentrations of As, Pb, and Cd. Hence, this isolate may play a role in bioremediation processes of heavy metal in polluted areas.
  2 3,061 477
Nanoemulsions as parenteral drug delivery systems for a new anticancer benzimidazole derivative: formulation and in-vitro evaluation
Rawia M Khalil, Mona Basha, Rabab Kamel
September-December 2015, 14(3):166-173
Background Recently, much attention has been paid to the application of nanoemulsions (NEs) as drug delivery systems. Besides their high solubilization capacity, NEs are powerful carrier systems because of their thermodynamic stability, ease of preparation, and high absorption rates. Aim The present work focuses on the design of stable and dilutable NEs for intravenous administration of a potent antitumor benzimidazole derivative, a poorly water-soluble active ingredient. Materials and methods NEs were formulated using ethanol as cosurfactant and Tween 20, Acconon MCF, and Labrasol as surfactants using the oil with maximum drug solubilization. Selected NEs were evaluated for droplet size, zeta potential, morphology, in-vitro release profile, and physical stability. Results The results revealed the development of eight NEs composed of 10% oleic acid with an infinite dilution capacity. NE3, NE6, and NE8 having the highest surfactant to cosurfactant ratio (3: 1) showed the best drug solubilization capacity. The NE droplets appeared almost spherical, ranging from 28.21 to 153.00 nm, with narrow distribution and relatively high zeta potential. NEs demonstrated sustained release profiles, whereas increasing surfactant to cosurfactant ratio was accompanied by increased drug release. NEs showed excellent physical stability with no phase separation or change in particle size. Conclusion Our results suggest that NEs can be used as a promising intravenous delivery system.
  2 2,223 451
Antioxidant and antiviral activities of the aqueous alcoholic leaf extract of Boscia angustifolia A. Rich. (Capparaceae) and its major component 'ombuin'
Maha M Salem, Sameh R Hussein, Reham El-Sharawy, Ahmed El-Khateeb, Eman A Ragab, Kamal M Dawood, Sabry I.M. El Negoumy
January-April 2016, 15(1):1-5
Background and objectives Boscia angustifolia A. Rich. is an endemic African species and has various folk medicinal uses. The present study aimed to investigate the polar compounds in B. angustifolia leaves and evaluate the antiviral and antioxidant activities of its extract and its major compound. Materials and methods The isolated compound (ombuin) was identified using chemical and spectroscopic tools (UV, 1H, and 13C NMR), and the polar constituents were characterized using gas chromatography mass spectrometry after silylation. Results and conclusion B. angustifolia A. Rich. leaves yielded 7,4′-dimethoxy quercetin 'ombuin'. Both the aqueous alcoholic extract and ombuin showed moderate antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl assay with IC50values 41.2 and 16.5μg/ml, respectively. Remarkable inhibition against H5N1 virus was found at concentration 80 μg/μl (63 and 68%, respectively). The gas chromatography mass spectrometry analysis revealed the presence of a complex mixture of 42 compounds, mainly acids, sugars, and their derivatives.
  2 1,504 250
Chiral separation and determination of enantiomeric purity of the pharmaceutical formulation of cefadroxil using coated and immobilized amylose-derived and cellulose-derived chiral stationary phases
Mohammed Nadjib Rebizi, Khaled Sekkoum, Nasser Belboukhari, Abdelkrim Cheriti, Hassan Y Aboul-Enein
May-August 2016, 15(2):88-97
Background and objectives In the present article, we describe the development of a simple, direct, and isocratic high-performance liquid-chromatographic method for chiral separation and the determination of the enantiomeric purity of cefadroxil. Cefadroxil has three chiral centers; the existence of eight different stereoisomers is possible. Only one of these isomers is currently under development as an antibiotic agent and, consequently, the other seven isomers are considered as unwanted chiral impurities. Materials and methods An analytical chiral separation was carried out to check its enantiomeric purity. The separation was carried out by exploiting the high efficiency of several coated/immobilized cellulose and amylose chiral stationary phases under normal-phase and polar-organic modes. The effects of type and concentration of the alcoholic modifiers, 2-propanol and ethanol, on the separation of stereoisomers were studied for optimum resolution. Results and conclusion Complete baseline separation of stereoisomers with good resolution was achieved within 40 min under normal-phase mode on Chiralpak IB column using hexane–2-propanol (60 : 40 v/v) as the mobile phase, without any organic additives, at a flow rate of 0.4 ml/min at 25°C and with the ultraviolet detection set at 268 nm. This process was found to be suitable for rapid enantiomeric purity analysis and a quality control of cefadroxil in pharmaceutical formulations without interference of the excipients. The chiral recognition mechanisms of separation were also discussed.
  2 1,775 180
Desmutagenic and antimutagenic potential of phenolics from Khaya grandifoliola (C.DC.), Meliaceae
Fatma A Hashem, Elsayed A Aboutabl, Sahar S EL Souda, Maysa Moharam, Amal A Mammoun, Manal Shabana
July-December 2013, 12(2):148-154
Background and objectives Antimutagenic or protective effects have been attributed to many classes of phytocompounds, mainly flavonoids and phenolic compounds, present in foods. Anticancer, antioxidant and anti-inflammatory activities of Khaya spp. have been reported, but their desmutagenic and antimutagenic activities were not studied. The aim of this study was to identify the phenolic contents of Khaya grandifoliola and correlate the desmutagenic and antimutagenic activities of these compounds. Materials and methods Desmutagenic and antimutagenic activities of specimen extracts of K. grandifoliola leaves and flowers were evaluated by measuring the inhibition of Salmonella typhimurium TA100 His + revertants induced by ethyl methanesulphonate and ribose lysine. The phenolic contents of K. grandifoliola leaf extracts were determined using column and paper chromatography. Spectroscopic analysis UV, 1 H NMR, 13 C NMR and electrospray ionization were applied to identify the isolated compounds. Results and conclusion Five phenolic compounds were isolated for the first time from K. grandifoliola leaves. These compounds were identified as quercetin 3-O-rhamnoglucoside (rutin), quercetin 3-O-rhamnoside, quercetin 3-O-glucoside, quercetin and 6-methoxycoumarin-7-O arabinofuranoside. The alcoholic extracts of both leaves and flowers (total and successive) of K. grandifoliola, rutin and quercetin rhamnoside isolated from the leaves, exhibited desmutagenic and antimutagenic activity against ethyl methanesulphonate-induced and ribose lysine-induced reversion.
  2 1,816 207
Diketopiperazine derivatives from Enterobacter cloacae isolated from the Red Sea alga Cystoseira myrica
Noha A Mohammed, Hossam M Hassan, Mostafa E Rateb, Eman F Ahmed, Usama W Hawas, Somayah Sameer, Rainer Ebel, Mounir M El-Safty, Mohammed S Abdel Hameed, Ola H Hammouda
July-December 2013, 12(2):163-172
Aim This study is an attempt to explore the biological activities of isolated endophytic bacteria from marine sources that were coded A1, A2, and A3 (Padina pavonica), A4 (Cystoseira myrica), A5 (Acanthophora dendroides), and A6 (Sargassum sabrepandum). The bacteria coded C1, C2, and C3 were isolated from the soft coral Nephthea mollis and S1 and S2 were isolates from the sponge Hymedesmia spp. The primary aim of the study was the identification of active compounds. Materials and methods The bioactive compounds were extracted using ethyl acetate from nutrient broth media; biological activities of the extracted metabolites and 16S rDNA identification of the most promising isolate were studied. The eight major fractions of the extract showed different composition patterns when identified by liquid chromatography/mass spectrometry analyses. Results and conclusion Agar diffusion assay showed inhibitory activities of A4 extracts against the growth of most pathogenic microorganisms. Identification using PCR 16S rDNA and electrophoresis confirmed 98% identity to the Enterobacter cloacae strain GH1 (ac: JF261136.1). Eight compounds out of fifteen in the extract were identified as diketopiperazine derivatives. The maximum growth of E. cloacae was obtained at 30°C, pH 7, with the addition of maltose and KI to the media. The free radical scavenging activity exhibited good antioxidant activity (72.19%, IC 50 = 1.266 mg/ml) on using 2.0 mg/ml of the crude extract. The extract showed a high antiviral activity towards Newcastle disease virus and avian influenza virus A(H5N1).
  2 2,931 251
Composition of lipoidal matter and evaluation of hepatoprotective, cytotoxic, and antioxidant activities of Khaya grandifoliola C.DC. growing in Egypt
Fatma A Hashem, Elsayed A Aboutabl, Sahar S El-Souda, Amany Selim, Kamel Shaker, Amal A Maamoun
January-June 2014, 13(1):13-20
Background and objectives Liver disease is one of the most common health problems. Schistosoma and hepatic viruses are widespread in Egypt, causing severe liver damage and posing a threat to life, which has motivated researchers to discover and evaluate new hepatoprotective agents, particularly from natural sources. The hepatoprotective effect of the leaf extracts of Khaya grandifoliola C.DC. were investigated, after determination of acute toxicity. The anticancer activity and antioxidant potential of the plant were evaluated, as well as the phytochemical composition of petroleum ether and chloroform extracts. Materials and methods Different extracts of K. grandifoliola C.DC. leaves were prepared and tested for hepatoprotective effect against carbon tetrachloride-induced liver damage in rats using silymarin as the reference drug. Anticancer activity was tested on HEPG2 (liver carcinoma cell line), HCT116 (colon carcinoma cell line), HELA (cervix carcinoma cell line), HEP2 (larynx carcinoma cell line), and MCF7 (breast carcinoma cell line). Its potency was compared with the reference drug Doxorubicin. The antioxidant potential was evaluated using 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay and ascorbic acid as the reference drug. After saponification of the petroleum ether extract, unsaponifiable matter and fatty acid methyl esters were analyzed by GC/MS. The chloroform extract was subjected to vacuum liquid chromatography. Results and conclusion The ethanolic extract of the leaves showed no toxicity up to 5 g/kg. It exhibited potent cytotoxic activity against HCT116 (colon carcinoma cell line) and MCF7 (breast carcinoma cell line), compared with doxorubicin as the standard. Also the ethanolic extract has significant free radical scavenger (100% inhibition) activity, compared with ascorbic acid. The extracts showed significant hepatoprotective and curative activity. GC/MS analysis of both unsaponifiable matter and fatty acids from petroleum ether extract allowed identification of 94.29% of the total unsaponifiable matter, (hentriacontane represented the major component, 11.98%) and 80.72% of the fatty acid methyl ester content (hexadecanoic acid methyl ester represented the major component, 31.68%). Vacuum liquid chromatography of chloroform extract led to isolation of two sterol glucosides (β-sitosterol-3-O-β-d-glucopyranoside and β-stigmasterol-3-O-β-d-glucopyranoside).
  2 1,867 233
Hunting for renal protective phytoconstituents in Artemisia judaica L. and Chrysanthemum coronarium L. (Asteraceae)
Howaida I Abd-Alla, Hanan F Aly, Nagwa M. M. Shalaby, Marzougah A Albalawy, Elsayed A Aboutabl
January-June 2014, 13(1):46-57
Aim This study aimed to evaluate the potential renal protective activity of Artemisia judaica L. and Chrysanthemum coronarium L., belonging to family Asteraceae, collected in Mountains of Tabuk, Kingdom of Saudi Arabia. The ameliorative role of petroleum ether, ethyl acetate, and methanol successive extracts thereof on renal hyperlipidemic and hyperglycemic rats was studied. Active compounds isolated from the bioactive ethyl acetate extract of A. judaica were characterized and identified. Material and methods Hyperlipidemia and hyperglycemia were induced in rats. Evaluation of renal protection was carried out through determination of kidney biochemical markers and histopathological examination. Kidney disorder biomarkers (creatinine and total urea) as well as kidney marker enzyme (glyceraldehyde-3-phosphate dehydrogenase) activity were evaluated. Oxidant-antioxidant status in kidney was assessed by determination of glutathione, lipid peroxide, and nitric oxide. The free radical scavenging activity was performed using 1,1-diphenyl-2-picrylhydrazyl. The extract exhibiting the most significant bioactivity was investigated for its phytoconstituents. Results and conclusion Treatment with A. judaica successive extracts, in particular ethyl acetate, effectively ameliorated diabetic renal dysfunction more than those of C. coronarium. The results revealed improvement in all the investigated parameters, which was confirmed by kidney histopathological analysis. Phytochemicals in the most promising extract (ethyl acetate extract of aerial parts of A. judaica) were isolated and characterized through their physical, chemical, chromatographic, and spectral analyses (UV, MS, 1 H NMR, and 13 C NMR). One sesquiterpene lactone, vulgarin ( 1 ); three triterpenes, taraxerol acetate ( 2 ), β-amyrin ( 3 ), and lupeol ( 4 ); a phytosterol, β-sitosterol ( 5 ); and four flavonoids, lutoelin-3’-methyl ether ( 6 ) and its glycoside, luteolin 3’-methyl ether-7-glucoside ( 7 ), luteolin-6,7,4’-trimethyl ether ( 8 ), and artemetin ( 9 ), were identified. All compounds are reported for the first time in the investigated plant except 1 , 6 , and 7 . The bioactivity may be attributed to the terpenoidal and flavonoidal compounds.
  2 3,131 325
Study of some biological activities of aqueous extract of ginger (Zingiber officinale)
Mohamed MI Helal, Mona Y Osman, Madeha OI Ghobashy, Wafaa A Helmy
July-December 2014, 13(2):144-150
Purpose This study was designed to evaluate the potential of two aqueous extracts of ginger rhizome under different extraction conditions (cold and hot water). Materials and methods Anticoagulant, fibrinolytic, antimicrobial, prebiotic, and antitumor activities were examined for the two aqueous extracts. The two aqueous extracts were then used for evaluation of yield, total carbohydrates, protein, and monosaccharide contents. The sulfation of crude extracts was carried out by chlorosulfonic acid as a sulfating agent in formamide. Results The results showed that sulfation modification of the two aqueous extracts increased significantly both the anticoagulation and the fibrinolytic activities, but did not affect the antimicrobial, prebiotic, or antitumor activities. However, the two native water extracts showed antibacterial activity against Escherichia coli only, but not for Staphylococcus aureus, and antifungal activity against Candida albicans. Conclusion The chemical modification of the two aqueous extracts of ginger by sulfation will increase significantly its anticoagulation and fibrinolytic activities while not affecting or improving the prebiotic and antimicrobial activities. However, the antitumor activity is high for both the native and the sulfated aqueous extracts of ginger. Thus, this result does not mean that the sulfation modification of the water extracts studied affected the antitumor activity.
  2 3,236 441
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