23 results on '"Mohamed H. Kalaba"'
Search Results
2. A statistical approach to enhance the productivity of Streptomyces baarensis MH-133 for bioactive compounds
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Mohamed H. Kalaba, Gamal M. El-Sherbiny, Osama M. Darwesh, and Saad A. Moghannem
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S. baarensis MH-133 ,Placket-Burman design ,Box-Behnken design ,ESKAPE ,Antibacterial activity ,Biotechnology ,TP248.13-248.65 ,Biology (General) ,QH301-705.5 - Abstract
The goal of this study was to use statistical optimization to change the nutritional and environmental conditions so that Streptomyces baarensis MH-133 could make more active metabolites. Twelve trials were used to screen for critical variables influencing productivity using the Placket-Burman Design method. S. baarensis MH-133 is significantly influenced by elicitation, yeast extract, inoculum size, and incubation period in terms of antibacterial activity. A total of 27 experimental trials with various combinations of these factors were used to carry out the response surface technique using the Box-Behnken design. The analyses revealed that the model was highly significant (p
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- 2024
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3. Iron/Copper/Phosphate nanocomposite as antimicrobial, antisnail, and wheat growth-promoting agent
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Nashwa H. Abdullah, Nouran A. Elbialy, Mohamed Abdelnaser Amer, Mostafa Kh. Gabr, Amira Salah El-Din Youssef, Mohamed H. Sharaf, M. E. Shehata, Mohamed H. Kalaba, and Elham R. S. Soliman
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Antisnail ,Antibacterial ,Conidial germination and mycelial growth inhibition ,Cytogenetic-toxicity ,Drought stress ,Iron/Copper/Phosphate nanocomposite ,Biotechnology ,TP248.13-248.65 - Abstract
Abstract Background One of the current challenges is to secure wheat crop production to meet the increasing global food demand and to face the increase in its purchasing power. Therefore, the current study aimed to exploit a new synthesized nanocomposite to enhance wheat growth under both normal and drought regime. The effectiveness of this nanocomposite in improving the microbiological quality of irrigation water and inhibiting the snail’s growth was also assessed. Results Upon the employed one-step synthesis process, a spherical Fe/Cu/P nanocomposite was obtained with a mean particle size of 4.35 ± 1.524 nm. Cu2+, Fe2+, and P4+ were detected in the dried nanocomposite at 14.533 ± 0.176, 5.200 ± 0.208, and 34.167 ± 0.203 mg/ml concentration, respectively. This nanocomposite was found to exert antibacterial activity against Escherichia coli and Salmonella typhi. It caused good inhibition percent against Fusarium oxysporum (43.5 ± 1.47%) and reduced both its germination rate and germination efficiency. The lethal concentration 50 (LC50) of this nanocomposite against Lanistes carinatus snails was 76 ppm. The treated snails showed disturbance in their feeding habit and reached the prevention state. Significant histological changes were observed in snail digestive tract and male and female gonads. Drought stress on wheat’s growth was mitigated in response to 100 and 300 ppm treatments. An increase in all assessed growth parameters was reported, mainly in the case of 100 ppm treatment under both standard and drought regimes. Compared to control plants, this stimulative effect was accompanied by a 2.12-fold rise in mitotic index and a 3.2-fold increase in total chromosomal abnormalities. Conclusion The finding of the current study could be employed to mitigate the effect of drought stress on wheat growth and to enhance the microbiological quality of irrigation water. This is due to the increased efficacy of the newly synthesized Fe/Cu/P nanocomposite against bacteria, fungi, and snails. This methodology exhibits potential for promoting sustainable wheat growth and water resource conservation.
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- 2024
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4. Melittin alcalase-hydrolysate: a novel chemically characterized multifunctional bioagent; antibacterial, anti-biofilm and anticancer
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Samia E. El-Didamony, Mohamed H. Kalaba, Mohamed H. Sharaf, Esmail M. El-Fakharany, Ali Osman, Mahmoud Sitohy, and Basel Sitohy
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bee venom ,melittin ,Apis mellifera ,antibacterial activity ,anticancer activity ,enzymatic hydrolysis ,Microbiology ,QR1-502 - Abstract
The prevalent life-threatening microbial and cancer diseases and lack of effective pharmaceutical therapies created the need for new molecules with antimicrobial and anticancer potential. Bee venom (BV) was collected from honeybee workers, and melittin (NM) was extracted from BV and analyzed by urea-polyacrylamide gel electrophoresis (urea-PAGE). The isolated melittin was hydrolyzed with alcalase into new bioactive peptides and evaluated for their antimicrobial and anticancer activity. Gel filtration chromatography fractionated melittin hydrolysate (HM) into three significant fractions (F1, F2, and F3), that were characterized by electrospray ionization mass spectrometry (ESI-MS) and evaluated for their antimicrobial, anti-biofilm, antitumor, and anti-migration activities. All the tested peptides showed antimicrobial and anti-biofilm activities against Gram-positive and Gram-negative bacteria. Melittin and its fractions significantly inhibited the proliferation of two types of cancer cells (Huh-7 and HCT 116). Yet, melittin and its fractions did not affect the viability of normal human lung Wi-38 cells. The IC50 and selectivity index data evidenced the superiority of melittin peptide fractions over intact melittin. Melittin enzymatic hydrolysate is a promising novel product with high potential as an antibacterial and anticancer agent.
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- 2024
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5. Biostimulation of tomato growth and biocontrol of Fusarium wilt disease using certain endophytic fungi
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Amer M. Abdelaziz, Mohamed H. Kalaba, Amr H. Hashem, Mohamed H. Sharaf, and Mohamed S. Attia
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Tomato ,Fusarium ,Endophytic ,Antioxidant enzymes ,Isozymes ,Resistance ,Botany ,QK1-989 - Abstract
Abstract Background Tomato plant (Solanum lycopersicum L.) suffers from numerous fungal pathogens that cause damage to yeild production qualitatively and quantitatively. One of the most destructive disease of tomato is Fusarium wilt that caused by soil borne fungus called F. oxysporum. Methods In this study, the anti-Fusarium capabilities of the foliar application of fungal endophytes extracts have been investigated on tomato under Fusarium challenges. Antifungal assay, inhibition of conidial germination, disease severity, photosynthetic pigments, osmolytes, secondary metabolites, oxidative stress, peroxidase (POD) and polyphenol oxidases (PPO) isozymes were tested for potential resistance of tomato growing under Fusarium infection. Results Ethyl acetate extracts of A. flavus MZ045563, A. fumigatus MZ045562 and A. nidulans MZ045561 exhibited antifungal activity toward F. oxysporum where inhibition zone diameters were 15, 12 and 20 mm, respectively. Moreover, extracts of all fungal isolates at concentration 7.5 mg/mL reduced conidia germination from 94.4 to 100%. Fusarium infection caused a destructive effects on tomato plant, high severity desiese index 84.37%, reduction in growth parameters, photosynthetic pigments, and soluble protein. However, contents of proline, total phenol, malondialdehyde (MDA), hydrogen peroxide (H2O2) and antioxidant enzymes activity were increased in tomato plants grown under Fusarium wilt. Treatment of healthy or infected tomato plants by ethyl acetate fungal extracts showed improvements in morphological traits, photosynthetic pigments, osmolytes, total phenol and antioxidant enzymes activity. Besides, the harmful impacts of Fusarium wilt disease on tomato plants have also been reduced by lowering MDA and H2O2 levels. Also, treated tomato plants showed different responses in number and density of POD and PPO isozymes. Conclusion It could be suggested that application of ethyl acetate extracts of tested fungal endophytes especially combination of A. flavus, A. nidulans and A. fumigatus could be commercially used as safe biostimulation of tomato plants as well as biofungicide against tomato Fusarium wilt disease.
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- 2022
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6. Biogenic synthesis of CuO-NPs as nanotherapeutics approaches to overcome multidrug-resistant Staphylococcus aureus (MDRSA)
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Gamal M. El-Sherbiny, Mohamed H. Kalaba, Mohammed H. Sharaf, Saad A. Moghannem, Ahmed A. Radwan, Ahmed A. Askar, Mahmoud K. A. Ismail, Ahmad S. El-Hawary, and Mahmoud A. Abushiba
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MDRSA ,CuO-NPs ,antibiotics ,synergistic effects. checkerboard assay ,time-kill assay ,cytotoxicity ,Biotechnology ,TP248.13-248.65 ,Medical technology ,R855-855.5 - Abstract
Due to the misuse of antibiotics, the multidrug-resistant Staphylococcus aureus (MDRSA) has caused serious infections and become more difficult to deal with. Here we propose to synthesise copper oxide nanoparticles (CuO-NPs) using a cell-free filter of Streptomyces rochei to enhance antibiotics activity against (MDRSA) and kill them. Characterisation of CuO-NPs using ultraviolet, dynamic light scattering, zeta potential, transmission electron microscopic (TEM), and X-ray diffraction, were investigated. The antibacterial action of the CuO-NPs was tested against standard strain and clinical isolates using the agar well diffusion method and the microdilution assay. The results showed the monodispersed spherical shape CuO-NPs with a mean diameter of 10.7 nm and were found to be active against (MDRSA). By a combination of CuO-NPs with different antibiotics, the highest synergistic effect was observed with cefoxitin, the minimum inhibitory concentration (MIC) was reduced to 6.5 for CuO-NPs, and 19.5 for cefoxitin. Time-kill assay showed the highest reduction in log10 colony-forming unit (CFU)/ml of initial inoculum of MRSA after 24 h. The HFB-4 cells cultured in the presence of CuO-NPs showed normal morphology with 100% viability at 8 µg/ml. TEM showed that combination (1/4 MIC cefoxitin +1/16 MIC CuO-NPs) highly damages bacterial cells’ shape. The biosynthesis CuO-NPs showed antibacterial activity against S. aureus suggesting a promising alternative in clinical.
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- 2022
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7. First report on isolation of Mucor bainieri from honeybees, Apis mellifera: Characterization and biological activities
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Mohamed H. Kalaba, Mahmoud H. Sultan, Mostafa A. Elbahnasawy, Samia E. El-Didamony, Nermeen M.El Bakary, and Mohamed H. Sharaf
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Fungi ,Mucor bainieri ,Honeybees ,Apis mellifera ,Antimicrobial activity ,Antioxidant activity ,Biotechnology ,TP248.13-248.65 - Abstract
Fungi are potential biocontrol agents and rich sources of secondary metabolites with demonstrated biological activities. This study aimed to isolate and identify fungi from surface-sterilized honeybees (Apis mellifera), as well as to evaluate their biological activities. One fungal isolate was obtained and identified morphologically and genetically as Mucor bainieri MK-Bee-2. Gas chromatography-mass spectroscopy (GC–MS) analysis of fungus crude extract, showed the existence of six major metabolites representing 92.48% of the total peak area. The crude extract of Mucor bainieri MK-Bee-2 was tested for antimicrobial, antioxidant, and antitumor activities. It demonstrated wide antimicrobial activities against human pathogenic Gram-positive and Gram-negative bacterial strains, as well as Candida albicans, with MIC values ranged from 62.5 to 250 µg/ml. The results revealed that the extract exhibited considerable antioxidant activities indicated by strong inhibition of both DPPH and ABTS free radicals. Additionally, the extract exhibited greater potential anticancer activity against both adenocarcinomic human non-small cell lung cancer cells (A549) [IC50 = 6.45 μg/ml], and immortal cell line hepatoma G2 (HepG2) human liver cancer cells [IC50 = 27.48 μg/ml] and higher selectivity in cancer cells than normal cell lines. Furthermore, the extract showed less cytotoxic activity against normal cells with higher IC50 values of 106.99 and 132.57 μg/ml against human lung fibroblast Wistar-38 (Wi-38) and oral epithelial cells (OEC), respectively. Taken together, the Mucor bainieri MK-Bee-2 extract comprises bioactive compounds as promising potential therapeutic candidates for the treatment of lung cancer. Strikingly, the extract sensitizes the lung cancer cells A549 to the ionizing radiation through the pro-apoptotic pathway as indicated by the annexin V flow cytometry analysis which showed that the extract reduced the apoptosis of lung cancer cells.
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- 2022
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8. Surf Redfish-Based ZnO-NPs and Their Biological Activity with Reference to Their Non-Target Toxicity
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Ahmed I. Hasaballah, Hussein A. El-Naggar, Ibrahim E. Abd-El Rahman, Fatimah Al-Otibi, Reham M. Alahmadi, Othman F. Abdelzaher, Mohamed H. Kalaba, Basma H. Amin, Mohamed M. Mabrouk, Ahmed G. A. Gewida, Marwa F. Abd El-Kader, and Mostafa A. Elbahnasawy
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sea cucumber ,surf redfish ,ZnO-NPs ,antibacterial ,larvicidal ,adulticidal ,Biology (General) ,QH301-705.5 - Abstract
The marine environment is a rich source of bioactive compounds. Therefore, the sea cucumber was isolated from the Red Sea at the Al-Ain Al-Sokhna coast and it was identified as surf redfish (Actinopyga mauritiana). The aqueous extract of the surf redfish was utilized as an ecofriendly, novel and sustainable approach to fabricate zinc oxide nanoparticles (ZnO-NPs). The biosynthesized ZnO-NPs were physico-chemically characterized and evaluated for their possible antibacterial and insecticidal activities. Additionally, their safety in the non-target organism model (Nile tilapia fish) was also investigated. ZnO-NPs were spherical with an average size of 24.69 ± 11.61 nm and had a peak at 350 nm as shown by TEM and UV-Vis, respectively. XRD analysis indicated a crystalline phase of ZnO-NPs with an average size of 21.7 nm. The FTIR pattern showed biological residues from the surf redfish extract, highlighting their potential role in the biosynthesis process. DLS indicated a negative zeta potential (−19.2 mV) of the ZnO-NPs which is a good preliminary indicator for their stability. ZnO-NPs showed larvicidal activity against mosquito Culex pipiens (LC50 = 15.412 ppm and LC90 = 52.745 ppm) and a potent adulticidal effect to the housefly Musca domestica (LD50 = 21.132 ppm and LD90 = 84.930 ppm). Tested concentrations of ZnO-NPs showed strong activity against the 3rd larval instar. Topical assays revealed dose-dependent adulticidal activity against M. domestica after 24 h of treatment with ZnO-NPs. ZnO-NPs presented a wide antibacterial activity against two fish-pathogen bacteria, Pseudomonas aeruginosa and Aeromonas hydrophila. Histopathological and hematological investigations of the non-target organism, Nile tilapia fish exposed to 75–600 ppm ZnO-NPs provide dose-dependent impacts. Overall, data highlighted the potential applications of surf redfish-mediated ZnO-NPs as an effective and safe way to control mosquitoes, houseflies and fish pathogenic bacteria.
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- 2023
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9. Biosynthesized ZnO-NPs Using Sea Cucumber (Holothuria impatiens): Antimicrobial Potential, Insecticidal Activity and In Vivo Toxicity in Nile Tilapia Fish, Oreochromis niloticus
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Mostafa A. Elbahnasawy, Hussein A. El-Naggar, Ibrahim E. Abd-El Rahman, Mohamed H. Kalaba, Saad A. Moghannem, Fatimah Al-Otibi, Reham M. Alahmadi, Othman F. Abdelzaher, Mohamed M. Mabrouk, Ahmed G. A. Gewida, Marwa F. AbdEl-Kader, and Ahmed I. Hasaballah
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biosynthesis ,nanoparticles ,zinc oxide ,sea cucumber ,Holothuria impatiens ,antimicrobial activity ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In this study, a sustainable and eco-friendly method was used to prepare zinc oxide nanoparticles (ZnO-NPs) using a sea cucumber aqueous extract. Then, ZnO-NPs were characterized by instrumental analysis (UV-vis, HR-TEM, XRD, FT-IR, and DLS) and evaluated for their possible antibacterial, antifungal, and insecticidal activities. Additionally, the toxicity of ZnO-NPs was evaluated in vivo against Nile Tilapia (Oreochromis niloticus). The sea cucumber was collected from the Gulf of Suez (Red Sea) at Al-Ain Al-Sokhna coast in Egypt and identified as Holothuria impatiens. The prepared Hi-ZnO-NPs peaked at 350 nm in UV–Vis spectral analysis. They showed quasi-spherical shaped particles with sizes ranging from 13 nm to 47 nm and a predominate size of 26 nm as indicated by HR-TEM. The XRD pattern of Hi-ZnO-NPs revealed a crystalline phase with an average size of 17.2 nm as calculated by Debye–Scherrer equation. FTIR analysis revealed the possible role of H. impatiens biological molecules in the biosynthesis process of ZnO-NPs. Hi-ZnO-NPs showed a negative zeta potential of −19.6 mV, demonstrating moderate stability. Biosynthesized Hi-ZnO-NPs revealed broad antimicrobial activity against Gram-positive bacteria (S. aureus ATCC 25923 and E. feacalis), Gram-negative bacteria (S. typhi, K. pneumonia and E. coli), and filamentous fungi (Aspergillus niger). Hi-ZnO-NPs demonstrated larvicidal activity against the mosquito, Culex pipiens (LC50 = 2.756 ppm and LC90 = 9.294 ppm), and adulticidal action against the housefly, Musca domestica (LD50 = 4.285 ppm and LD90 = 22.847 ppm). Interestingly, Hi-ZnO-NPs did not show mortality effects against Nile tilapia fish (Oreochromis niloticus), highlighting the potential safety of Hi-ZnO-NPs to highly exposed, non-target organisms. However, histopathological and hematological investigations provided dose-dependent impacts of Hi-ZnO-NPs to Nile tilapia. Overall, data provide an eco-friendly approach for synthesizing novel Hi-ZnO-NPs with multiple biomedical properties and potentially low toxicity to Nile tilapia fish.
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- 2023
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10. New combination approaches to combat methicillin-resistant Staphylococcus aureus (MRSA)
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Mohamed H. Sharaf, Gamal M. El-Sherbiny, Saad A. Moghannem, Mohamed Abdelmonem, Islam A. Elsehemy, Ahmed M. Metwaly, and Mohamed H. Kalaba
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Medicine ,Science - Abstract
Abstract The herbal products proved to be more promising antimicrobials even though their antimicrobial activity is milder than commercially available antibiotics. Moreover, herbal drugs may act synergistically with antibiotics to kill microbes. In this study, we aimed to enhance the activity of penicillin against MRSA through combination with the active saponin fraction isolated from the Zygophyllum album plant. Three different types of metabolites (saponins, sterols, and phenolics) have been extracted from Zygophyllum album with ethanol and purified using different chromatographic techniques. The antibacterial activity of crude extract and the separated metabolites were checked against MRSA isolates, Saponin fraction (ZA-S) was only the active one followed by the crude extract. Therefore, the compounds in this fraction were identified using ultra-high-performance liquid chromatography connected to quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS) operated in positive and negative ionization modes. UHPLC/QTOF-MS revealed the presence of major six ursane-type tritepenoidal saponins (Quinovic acid, Quinovic acid 3β-O-β-D-quinovopyranoside, Zygophylloside C, Zygophylloside G, Zygophylloside K and Ursolic acid), in addition to Oleanolic acid. Interaction studies between saponin fraction and penicillin against MRSA were performed through the checkerboard method and time-kill assay. According to checkerboard results, only three combinations showed a fractional inhibitory concentration index less than 0.5 at concentrations of (62.5 + 312.5, 62.5 + 156.25, and 62.5 + 78.125 of penicillin and ZA-S, respectively). Time kill assay results showed that the highest reduction in log10 colony-forming unit (CFU)/ml of initial inoculum of MRSA after 24 h occurred by 3.7 at concentrations of 62.5 + 312.5 (µg/µg)/ml of penicillin and ZA-S, respectively. Thus, the combination between saponin fraction of Zygophyllum album and penicillin with these concentrations could be a potential agent against MRSA that can serve as possible model for new antibacterial drug.
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- 2021
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11. Green Synthesized ZnO Nanoparticles Mediated by Streptomyces plicatus: Characterizations, Antimicrobial and Nematicidal Activities and Cytogenetic Effects
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Mohamed H. Kalaba, Saad A. Moghannem, Ahmad S. El-Hawary, Ahmed A. Radwan, Mohamed H. Sharaf, and Abdelghany S. Shaban
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ZnO-NPs ,Streptomyces plicatus MK-104 ,antimicrobial activity ,plant pathogens ,root-knot nematodes ,cyto-genotoxicity ,Botany ,QK1-989 - Abstract
Zinc oxide nanoparticles (ZnO-NPs) are regarded as one of the most promising kinds of materials in a variety of fields, including agriculture. Therefore, this study aimed to biosynthesize and characterize ZnO-NPs and evaluate their different biological activities. Seven isolates of actinomycetes were obtained and screened for ZnO-NPs synthesis. The isolate MK-104 was chosen and identified as the Streptomyces plicatus MK-104 strain. The biosynthesized ZnO-NPs exhibited an absorbance peak at 350 nm and were spherical in shape with an average size of 21.72 ± 4.27 nm under TEM. XRD and DLS methods confirmed these results. The biosynthesized ZnO-NPs demonstrated activity against plant pathogenic microbes such as Erwinia amylovora, Aspergillus flavus, Aspergillus niger, Fusarium oxysporum, Fusarium moniliform and Alternaria alternata, with MIC values ranging from 15.6 to 500 µg/mL. Furthermore, ZnO-NPs had a significant effect on Meloidogyne incognita, with death percentages of 88.2, 93.4 and 96.72% after 24, 48 and 72 h of exposure, respectively. Vicia faba seeds were treated with five concentrations of ZnO-NPs (12.5, 25, 50, 100 and 200 µg/mL). Low-moderate ZnO-NP concentrations (12.5–50 µg/mL) were shown to promote seed germination and seedling development, while the mitotic index (MI) decreased as the dosage of ZnO-NPs increased. Micronuclei (MNs) and the chromosomal abnormality index increased as well.
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- 2021
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12. Antibacterial activity of essential oils for combating colistin-resistant bacteria
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Abdullah M. Foda, Mohamed H. Kalaba, Gamal M. El-Sherbiny, Saad A. Moghannem, and Esmail M. El-Fakharany
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Microbiology (medical) ,Infectious Diseases ,Bacteria ,Colistin ,Eucalyptus Oil ,Virology ,Oils, Volatile ,Humans ,Microbial Sensitivity Tests ,Microbiology ,Anti-Bacterial Agents - Abstract
Colistin (polymyxin E) is a bactericidal antibiotic used to treat severe infections caused by multidrug-resistant Gram-negative bacteria. The product of theTwenty-seven bacterial isolates were collected from patients who were admitted to the National Cancer Institute, Cairo, Egypt, and processed using standard microbiological methods. Essential oils were purchased from AB Chem Company, Egypt, screened for antibacterial, cytotoxic activity, and (GC-MS) analysis.A total of 5 bacterial isolates were resistant to colistin with minimum inhibitory concentration (MIC) ranging from 6.25-200 µg/ml. Cinnamon oil exhibited the highest activity against colistin-resistant strains followed by thyme and eucalyptus oil. The (MIC) of cinnamon oils against resistant strains ranged from 4.88 to 312.5 µg/ml. Moreover, mcr-1 gene expression was extremely down-regulated after the treatment of bacterial strains with cinnamon oil and decreased to 20-35-fold. Examination of treated bacterial cells with sub-inhibitory concentrations under transmission electron microscopy showed various abnormalities occurred in most of these cells.Cinnamon oil exhibits antibacterial activity against colistin-resistant strains, showing it as a promising natural alternative in clinical therapy.
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- 2022
13. A new strategy to integrate silver nanowires with waterborne coating to improve their antimicrobial and antiviral properties
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Mohamed H. Sharaf, Adham M. Nagiub, Salem S. Salem, Mohamed H. Kalaba, Esmail M. El Fakharany, and Hamada Abd El-Wahab
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Materials Chemistry ,Surfaces, Coatings and Films - Abstract
Purpose This study aims to focus on the preparation and characterization of the silver nanowire (AgNWs), as well as their application as antimicrobial and antivirus activities either with incorporation on the waterborne coating formulation or on their own. Design/methodology/approach Prepared AgNWs are characterized by different analytical instruments, such as ultraviolet-visible spectroscope, scanning electron microscope and X-ray diffraction spectrometer. All the paint formulation's physical and mechanical qualities were tested using American Society for Testing and Materials, a worldwide standard test procedure. The biological activities of the prepared AgNWs and the waterborne coating based on AgNWs were investigated. And, their effects on pathogenic bacteria, antioxidants, antiviral activity and cytotoxicity were also investigated. Findings The obtained results of the physical and mechanical characteristics of the paint formulation demonstrated the formulations' greatest performance, as well as giving good scrub resistance and film durability. In the antimicrobial activity, the paint did not have any activity against bacterial pathogen, whereas the AgNWs and AgNWs with paint have similar activity against bacterial pathogen with inhibition zone range from 10 to 14 mm. The development of antioxidant and cytotoxicity activity of the paint incorporated with AgNWs were also observed. The cytopathic effects of herpes simplex virus type 1 (HSV-1) were reduced in all three investigated modes of action when compared to the positive control group (HSV-1-infected cells), suggesting that these compounds have promising antiviral activity against a wide range of viruses, including DNA and RNA viruses. Originality/value The new waterborne coating based on nanoparticles has the potential to be promising in the manufacturing and development of paints, allowing them to function to prevent the spread of microbial infection, which is exactly what the world requires at this time.
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- 2022
14. Antimicrobial, Antioxidant, Cytotoxic Activities and Phytochemical Analysis of Fungal Endophytes Isolated from Ocimum Basilicum
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Mohamed H. Kalaba, Amer M. Abdelaziz, Amr H. Hashem, Mohamed H. Sharaf, and Ahmed A. Radwan
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food.ingredient ,biology ,Chemistry ,Bacillus cereus ,Basilicum ,Bioengineering ,Aspergillus flavus ,General Medicine ,Ocimum ,biology.organism_classification ,Antimicrobial ,Applied Microbiology and Biotechnology ,Biochemistry ,Antioxidants ,Plant use of endophytic fungi in defense ,Aspergillus fumigatus ,Microbiology ,food ,Aspergillus nidulans ,Molecular Biology ,Biotechnology - Abstract
Fungal endophytes are living inside plants without any harmful effects; the prospecting about them is increased day by day because they can produce bioactive compounds which can be used in different applications. Herein, the current study was aimed to isolate the endophytic fungi from the Ocimum basilicum plant as safe microorganisms and evaluate their biological activities. The results illustrated that three endophytic fungal strains were isolated and identified morphologically and genetically as Aspergillus nidulans, Aspergillus fumigatus, and Aspergillus flavus and deposited in gene bank under accession numbers MZ045561, MZ045562, and MZ045563 respectively. Moreover, cell-free filtrates of endophytic fungal strains were extracted using ethyl acetate, where these crude extracts exhibited promising antimicrobial activity against Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa, Klebsiella pneumonia, and Candida albicans at a concentration of 1000 µg/mL. Furthermore, these endophytic strains exhibited a potential antioxidant activity where IC50 of the crude extract of A. nidulans, A. fumigatus, and A. flavus were (166.3, 68.4, and 347.1 µg/mL) and (151.2, 77.9, and 246.3 µg/mL) using DPPH and ABTS methods, respectively. Furthermore, the ethyl acetate crude extracts of these endophytic fungi did not exhibit any cytotoxic effect against Vero and Wi 38 normal cells. GC–MS analysis of the crude extract of A. nidulans, A. fumigatus, and A. flavus indicated the presence of 22, 22, and 20 active compounds, respectively. The major compounds in the fungal extracts are belonging to fatty acids, fatty acid esters, tetrahydrofurans, and sterols. In conclusion, the isolated endophytic A. nidulans, A. fumigatus, and A. flavus from Ocimum basilicum are promising sources for bioactive compounds.
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- 2021
15. Antifungal and antibiofilm activities of bee venom loaded on chitosan nanoparticles: a novel approach for combating fungal human pathogens
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Samia E. El-Didamony, Mohamed H. Kalaba, Esmail M. El-Fakharany, Mahmoud H. Sultan, and Mohamed H. Sharaf
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Physiology ,General Medicine ,Applied Microbiology and Biotechnology ,Biotechnology - Abstract
The prevalence of opportunistic human fungal pathogens is increasing worldwide, and antimicrobial resistance is one of the greatest medical challenges the world faces. Therefore, this study aimed to develop a novel agent to control fungal pathogens. The honeybee products (honey, royal jelly, propolis, bee bread, and bee venom) were screened against unicellular fungal (UCF) pathogens (Cryptococcus neoformans, Kodamaea ohmeri, and Candida albicans) and the bee venom was only exhibited an inhibitory effect against them. The protein contents of crude bee venom were separated using the gel filtration technique into eight fractions which were visualized on sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) to confirm the presence of five bands with molecular weights of 65, 43, 21, 15, and 3 KDa. Bee venom (BV) of Apis mellifera loaded chitosan nanoparticles were prepared by the ionotropic gelation method. The encapsulation efficiency%, average size, zeta potentials, and surface appearance by Transmission electron microscope (TEM) were evaluated for the prepared nanoparticles. The minimum inhibitory concentration (MIC) of crude BV and BV loaded chitosan nanoparticles (BV-CNPs) was evaluated against the offer mentioned UCF where the MIC values of crude BV were 6.25, 3.12 & 6.25 while MIC values in the case of BV-CNPs were decreased to 3.12, 3.12 & 1.56 mg/ml against C. neoformans, K. ohmeri and C. albicans, respectively. Also, the results showed that BV-CNPs suppressed the biofilm formation as well as yeast to hyphal transition formed by the examined UCF. These results revealed that BV-CNPs are a promising natural compound for fungal pathogens treatment. Graphical abstract
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- 2022
16. New combination approaches to combat methicillin-resistant Staphylococcus aureus (MRSA)
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Ahmed M. Metwaly, Mohamed H. Kalaba, Mohamed H. Sharaf, Islam A. Elsehemy, Mohamed Gamal Abdelmonem, Gamal M. El-Sherbiny, and Saad A. Moghannem
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0301 basic medicine ,Methicillin-Resistant Staphylococcus aureus ,medicine.drug_class ,Science ,030106 microbiology ,Antibiotics ,Saponin ,Microbial Sensitivity Tests ,Microbiology ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,Ursolic acid ,Drug Discovery ,medicine ,Humans ,Oleanolic acid ,Chromatography, High Pressure Liquid ,chemistry.chemical_classification ,Multidisciplinary ,Chromatography ,Plant Extracts ,Zygophyllum album ,Health care ,Disease Management ,Drug Synergism ,Staphylococcal Infections ,Antimicrobial ,Combined Modality Therapy ,Anti-Bacterial Agents ,Penicillin ,030104 developmental biology ,Treatment Outcome ,chemistry ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Medicine ,Drug Therapy, Combination ,Antibacterial activity ,medicine.drug - Abstract
The herbal products proved to be more promising antimicrobials even though their antimicrobial activity is milder than commercially available antibiotics. Moreover, herbal drugs may act synergistically with antibiotics to kill microbes. In this study, we aimed to enhance the activity of penicillin against MRSA through combination with the active saponin fraction isolated from the Zygophyllum album plant. Three different types of metabolites (saponins, sterols, and phenolics) have been extracted from Zygophyllum album with ethanol and purified using different chromatographic techniques. The antibacterial activity of crude extract and the separated metabolites were checked against MRSA isolates, Saponin fraction (ZA-S) was only the active one followed by the crude extract. Therefore, the compounds in this fraction were identified using ultra-high-performance liquid chromatography connected to quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS) operated in positive and negative ionization modes. UHPLC/QTOF-MS revealed the presence of major six ursane-type tritepenoidal saponins (Quinovic acid, Quinovic acid 3β-O-β-D-quinovopyranoside, Zygophylloside C, Zygophylloside G, Zygophylloside K and Ursolic acid), in addition to Oleanolic acid. Interaction studies between saponin fraction and penicillin against MRSA were performed through the checkerboard method and time-kill assay. According to checkerboard results, only three combinations showed a fractional inhibitory concentration index less than 0.5 at concentrations of (62.5 + 312.5, 62.5 + 156.25, and 62.5 + 78.125 of penicillin and ZA-S, respectively). Time kill assay results showed that the highest reduction in log10 colony-forming unit (CFU)/ml of initial inoculum of MRSA after 24 h occurred by 3.7 at concentrations of 62.5 + 312.5 (µg/µg)/ml of penicillin and ZA-S, respectively. Thus, the combination between saponin fraction of Zygophyllum album and penicillin with these concentrations could be a potential agent against MRSA that can serve as possible model for new antibacterial drug.
- Published
- 2021
17. Design and synthesis of new 4-(2-nitrophenoxy)benzamide derivatives as potential antiviral agents: molecular modeling and in vitro antiviral screening
- Author
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Esmail M. El-Fakharany, Mohamed H. Kalaba, Abdallah E. Abdallah, Hazem Elkady, Noura M. Abo Shama, Mohamed H. Sharaf, Ahmed Mostafa, Sally I. Eissa, Sara H. Mahmoud, Ahmed A. Al-Karmalawy, and Mohamed S Alesawy
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chemistry.chemical_classification ,biology ,Molecular model ,viruses ,In silico ,General Chemistry ,Coxsackievirus ,biology.organism_classification ,Catalysis ,In vitro ,Deubiquitinating enzyme ,chemistry.chemical_compound ,Enzyme ,chemistry ,Biochemistry ,Materials Chemistry ,biology.protein ,Antiviral screening ,Benzamide - Abstract
Regarding the crucial role of deubiquitinase (DUB) enzymes in many viruses, in particular, Adenovirus, HSV-1, coxsackievirus, and SARS-CoV-2, DUB inhibition was reported as an effective new approach to find new effective antiviral agents. In the present study, a new wave of 4-(2-nitrophenoxy)benzamide derivatives was designed and synthesized to fulfill the basic pharmacophoric features of DUB inhibitors. The molecular docking of the designed compounds against deubiquitinase enzymes of the aforementioned viruses was carried out. Significant molecular docking results directed us to conduct in vitro antiviral screening against the aforementioned viruses. The biological data showed very strong to strong antiviral activities with IC50 values ranging from 10.22 to 44.68 μM against Adenovirus, HSV-1, and coxsackievirus. Compounds 8c, 8d, 10b, and 8a were found to be the most potent against Adenovirus, HSV-1, coxsackievirus, and SAR-CoV-2, respectively. Also, the CC50 values of the examined compounds ranged from 72.93 to 120.50 μM. Finally, the in silico ADMET and toxicity studies demonstrated that the tested members have a good profile of drug-like properties. Furthermore, we concluded the structure–activity relationship (SAR) of the newly designed and synthesized compounds regarding their in vitro results, which may help medicinal chemists in further optimization to obtain more potential antiviral candidates in the near future as well.
- Published
- 2021
18. New Gd(I)/Cs(III) complexes of benzil‐based thiocarbohydrazone macrocyclic ligand: Chemical synthesis, characterization, and study their biological effectiveness as antibacterial, antioxidant, and antiviral additives for polyurethane surface coating
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H. Abd El-Wahab, Essam Eliwa, Walid Elgammal, Maha Elsawy, Mohamed H. Kalaba, Esmail El Fakharany, Medhat Owda, and Mohamed Sharaf
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Inorganic Chemistry ,General Chemistry - Published
- 2022
19. New Series of VEGFR-2 Inhibitors and Apoptosis Enhancers: Design, Synthesis and Biological Evaluation
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Abdallah E Abdallah, Reda R Mabrouk, Mohamed R Elnagar, Amel Mostafa Farrag, Mohamed H Kalaba, Mohamed H Sharaf, Esmail M El-Fakharany, Dina Abed Bakhotmah, Eslam B Elkaeed, and Maged Mohammed Saleh Al Ward
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Pharmacology ,Drug Design, Development and Therapy ,Molecular Structure ,Pharmaceutical Science ,Antineoplastic Agents ,Apoptosis ,Vascular Endothelial Growth Factor Receptor-2 ,Molecular Docking Simulation ,Structure-Activity Relationship ,Drug Discovery ,Humans ,Caco-2 Cells ,Drug Screening Assays, Antitumor ,Protein Kinase Inhibitors ,Cell Proliferation - Abstract
Abdallah E Abdallah,1 Reda R Mabrouk,1 Mohamed R Elnagar,2 Amel Mostafa Farrag,3 Mohamed H Kalaba,4 Mohamed H Sharaf,4 Esmail M El-Fakharany,5 Dina Abed Bakhotmah,6 Eslam B Elkaeed,7 Maged Mohammed Saleh Al Ward1 1Pharmaceutical Medicinal Chemistry & Drug Design Department, Faculty of Pharmacy (Boys), Al-Azhar University, Cairo, 11884, Egypt; 2Department of Pharmacology and Toxicology, Faculty of Pharmacy, Al-Azhar University, Cairo, 11884, Egypt; 3Pharmaceutical Chemistry Department, Faculty of Pharmacy (Girls), Al-Azhar University, Cairo, Egypt; 4Botany and Microbiology Department, Faculty of Science, Al-Azhar University, Cairo, 11884, Egypt; 5Protein Research Department, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, New Borg El Arab, Egypt; 6Chemistry Department, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia; 7Department of Pharmaceutical Sciences, College of Pharmacy, AlMaarefa University, Riyadh, 13713, Saudi ArabiaCorrespondence: Abdallah E Abdallah; Maged Mohammed Saleh Al Ward, Pharmaceutical Medicinal Chemistry & Drug Design Department, Faculty of Pharmacy (Boys), Al-Azhar University, Cairo, 11884, Egypt, Email Abdulla_emara@azhar.edu.eg; majed1000ward@hotmail.comBackground: Cancer is still a major world health threat, causing a high rate of mortality. VEGFR-2 inhibitor anticancer agents are of great significance. However, they showed some serious side effects.Purpose: To discover new effective and safer anticancer agents, a new series of piperazinylquinoxaline-based derivatives was designed and synthesized on the basis of the pharmacophoric features of VEGFR-2 inhibitor drugs.Methods: The new candidates were evaluated against A549 lung cancer cells, HepG-2 hepatoma cells, Caco-2 colon cancer cells, MDA breast cancer cells, and VEGFR-2 kinase. Moreover, cell cycle kinetics and apoptosis rates were studied in HepG-2 cells treated with compound 11, which was the most promising candidate.Results: The new derivatives revealed better antitumor results (IC50 from 6.48 to 38.58 μM) against the aforementioned cancer cell lines than sorafenib. Also, the new candidates showed VEGFR-2 inhibition with IC50 values ranging from 0.19 to 0.60 μM compared to 0.08 μM for sorafenib. Compound 11, meanwhile, showed IC50 values equal to 10.61, 9.52, 12.45, 11.52, and 0.19 μM against the cancer cell lines and VEGFR-2, respectively. Moreover, compound 11 raised the apoptosis rate in HepG-2 cells from 5% to 44% and caused 4, 2.3, and 3-fold increases in BAX/Bcl-2 ratio, caspase-3 level, and P53 expression, respectively, compared to control untreated cells. Finally, the new derivatives displayed the correct binding mode into VEGFR-2 kinase pocket, giving interactions with the essential residues.Conclusion: This work suggests that compound 11 is a very significant anticancer candidate, and piperazinylquinoxaline is an important scaffold in the development of new potential effective and safer VEGFR-2 inhibitor agents.Keywords: anticancer, apoptosis, molecular modeling, piperazinylquinoxaline, VEGFR-2 kinase, Western blot
- Published
- 2022
20. Enhancement of Antibiotics activity by microbially synthesized silver nanoparticles
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Mohamed H. Kalaba, Ali M. Saeed, Mahmoud Abushiba, Einas El Shatoury, Gamal M. El-Sherbiny, and Saad A. Moghannem
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medicine.drug_class ,Antibiotics ,Nanoparticle ,General Medicine ,Silver nanoparticle ,Absorbance ,Penicillin ,Silver nitrate ,chemistry.chemical_compound ,chemistry ,medicine ,Zeta potential ,Antibacterial activity ,Nuclear chemistry ,medicine.drug - Abstract
Biological synthesis of nanoparticles is a promising approach that is comparatively inexpensive and eco-friendly. Among various microorganisms, actinobacteria have been found to be efficient in the synthesis of nanomaterials. In thisstudy, extracellular biosynthesis of silver nanoparticles (Ag-NPs) was investigated by mixing silver nitrate with culture filtrate of Streptomyces rochei strain MFA-37.The biosynthesized Ag-NPs were characterized by UV–Vis spectrophotometric analysis, and showed a peak of absorbance at 440 nm. Fourier transform infrared (FTIR) analysis showed amines and amides that are responsible for the stabilization of Ag-NPs. The morphology and size of nanoparticles were determined using high-resolution transmission electron microscopy, XRD and DLS techniques which indicated well dispersed, spherical Ag-NPs sized 2–20 nm, and the zeta potential of AgNPs reached -20.5 mV. Enhancement of antibacterial activity of fourteen antibiotics was conducted by combining antibiotics with synthesized AgNPs. The synergistic activities of AgNPs combination with antibiotics were determined using disc diffusion against two multi-drug resistant Staphylococcus aureus SA-185 and SA-325 recovered from Libya. The highest synergistic effects were 6.11 and 6.37 folds for Penicillin followed by 6.11 and 4.44 folds for Ciprofloxacin and 6.11 and 3.69 folds for Erythromycin for MRSA-185 and MRSA-325 , respectively. This activity of AgNPs and antibiotics could be valuable for the manufacture of hybrid drugs to kill or inhibit the MRSA infection especially in case of superficial injuries.
- Published
- 2019
21. Sustainable Repairing and Improvement of Concrete Properties Using Bacterial Consortium Isolated From Egypt
- Author
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Abdelzaher E. A. Mostafa, Mohamed E. A. Ouf, Waleed F. Tawhed, Mohamed H. Kalaba, Gamal M. El-Sherbiny, and Hala H. A. Mahmoud
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Engineering ,business.industry ,business ,Construction engineering - Abstract
The small cracks in concrete constructions are inevitable due to deterioration during their service life throughout different load combination factors. In this study, we aimed to isolate, identify, and construct a bacterial consortium able to heal small cracks of concrete and enhance the different properties of concrete. Six isolates of bacillus, endospore-forming bacteria were isolated. There are only three isolates out of the six coded as NW-1, MK and NW-9 were showed the ability to produce urease enzyme and able to grow at 60°C with optimum growth at a temperature of 40°C. These isolates were survived in high pH, where isolate NW-1 was tolerated pH up to 11 with optimum growth at 10 while the isolates NW-9 and MK showed growth at pH 12 with an ideal growth at 10. CaCO3 production was observed by the three bacterial isolates whether in pure or mixed cultures (bacterial consortium) but the consortium consisting of MK and NW-9 was significantly the highest in productivity among them. Therefore, these two isolates were identified using 16s as Bacillus flexus MK-FYT-3 and Bacillus haynesii MK-NW-9 and deposited to GenBank under accession numbers MN965692 and MN965693 respectively. The effect of bacteria on some properties of concrete was studied, and the results showed that the compressive and tensile strengths of bio-concrete specimens were significantly increased by 31.29, 29 % after 7 days and 36.3, 39 % after 28 days of curing compared to control specimens. The results of permeability indicated that the bio-concrete specimens significantly showed less permeability than the control specimens by 21.1, 23.1% after 7 and 28 of curing, respectively. To determine the concrete density, Ultrasonic Pulse Velocity (UPV) test was performed, and the bio-concrete specimens gave higher values than control specimens by 26 and 20% after curing for 7 and 28 days, respectively. Also, surface healing of concrete was observed visually, the bio-concrete showed white precipitates around and inside the cracks after 7 days, which led to almost complete sealing of concrete after 28 days of curing, while the control samples were showed only very slight deposits on the surface and away from the cracks. The micro-analysis of concrete samples using SEM and XRD were done. It was found that the bio-concrete specimens showed crystalline precipitate with different shapes under SEM, while no such deposits appeared in the control specimens. On the other hand, the XRD profile was explained the characteristic peaks of calcium carbonate in both the bio-concrete and the control specimens, but the peak intensity was higher in the bio-concrete than the control specimens. This reflects the effectiveness of bacterial consortium in repairing and preventing the concrete cracks from spreading in addition to improving the various properties of concrete leading to increasing its life and sustainability.
- Published
- 2021
22. Structural, physical characteristics and biological activities assessment of scleroglucan from a local strain Athelia rolfsii TEMG
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Azza M. Noor El Deen, Islam A. Elsehemy, Ibrahim H. Tolba, Mohamed A.M. Farid, Saad A. Moghannem, Hassan M. Awad, and Mohamed H. Kalaba
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Athelia rolfsii ,Chemical Phenomena ,Cell Survival ,02 engineering and technology ,Polysaccharide ,Biochemistry ,Homopolysaccharide ,03 medical and health sciences ,Structure-Activity Relationship ,Structural Biology ,Polysaccharides ,Humans ,Cytotoxicity ,Molecular Biology ,Glucans ,030304 developmental biology ,EC50 ,Cytopathic effect ,chemistry.chemical_classification ,0303 health sciences ,biology ,Strain (chemistry) ,Molecular Structure ,Chemistry ,Basidiomycota ,Monosaccharides ,General Medicine ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Antimicrobial ,Molecular Weight ,0210 nano-technology ,Rheology - Abstract
Athelia rolfsii TEMG (MH 236106) an exopolysaccharide (EPS) producing fungal strain was isolated and identified. Extraction, purification, characterization, antimicrobial, antioxidant, antiviral and antitumor activities of the polysaccharide were investigated. It characterized as a homopolysaccharide of glucose with a molecular weight of 345.622 kDa. The identification of the polysaccharide was conducted using scanning electron microscopy, energy dispersive X-ray analysis, 1H and 13C NMR spectra. The existence of β-1,3 and β-1,6 linkages suggests that EPS could be scleroglucan. The purified scleroglucan showed considerable antibacterial and antioxidant activities. The results indicated that, there was no cytotoxicity on normal cell (W138) and no effect on tumor cell lines including HepG2 and PC3 showing IC50 of 5096.83, 5885.80 and 4803.90 μg/mL, respectively. The results showed also that Sclg could reduce the cytopathic effect by 50% (EC50) at 15 and 50 μg/mL of herpes simplex virus type-1 (HSV-1) and influenza virus (H5N1), respectively.
- Published
- 2019
23. Characterization of heavy metal and antibiotic-resistant bacteria isolated from polluted localities in Egypt
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Mohamed H. Kalaba, Mohamed Hanafy El-Sayed, Islam A. Elsehemy, Saad A. Moghannem, Gamal M. El-Sherbiny, and Bahgat M. Refaat
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Cadmium ,Pharmaceutical Science ,chemistry.chemical_element ,Biology ,Toxicology ,biology.organism_classification ,16S ribosomal RNA ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Applied Microbiology and Biotechnology ,Enrichment culture ,Microbiology ,Pseudomonas stutzeri ,Bioremediation ,chemistry ,Wastewater ,Food science ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,Arsenic ,Bacteria - Abstract
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.
- Published
- 2015
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