Microbial Chitinases — Production, Characterization, Purification and their Biotechnological and Therapeutic Applications: An Integrated Review , Medhat A. Abu-Tahon, Heba I. Aboelmagd, , Manal M. Housseiny, , Ahmad M. Abdel‐ Mageed, , Nada Daifalla, , Adaugo C. Isichei, , Sahar Algadi, , Yahia H. Ali, , Intisar K. Saeed, , Howayada M. Mostafa, , Salma Y. S. Elsheikh, , Ali M. Ali, , Amani A. S. Abdelaziz, , Ishraga Izzeldin, , Nermien H. Seddek, , Assad A. Rezigalla, , Elhadi Miskeen, , Ali M. S. Eleragi, , Mohammed-Elfatih Twfie, , George S. Isaac, and Bioresources, 2026 Chitin is the second most abundant natural polysaccharide after cellulose and consists of N-acetyl-D-glucosamine units linked by β-1,4-glycosidic bonds. In nature, chitin does not accumulate due to the synergistic action of chitinolytic enzymes. Based on their catalytic domains, chitinases are classified into glycosyl hydrolase families GH18 and GH19. They are widely produced by bacteria and filamentous fungi. Different types of chitinolytic enzymes, including endochitinases, exo-acting enzymes, and N-acetylglucosaminidases, have been reported to exhibit antimicrobial and insecticidal activities, making them valuable tools for controlling phytopathogenic fungi and insect pests. Chitin degradation generates chitooligosaccharides (COS), which possess diverse biological properties such as antimicrobial, antioxidant, anti-inflammatory, and antitumor activities, contributing to improved human health. Microbial chitinases are also applied in several industrial and environmental processes, including protoplast formation, single-cell protein production, and dye removal. Advances in recombinant expression and genetic engineering have enhanced chitinase production, stability, and catalytic efficiency. Moreover, recombinant chitinases have been successfully utilized in biocontrol strategies and in developing transgenic plants with increased resistance to phytopathogens. This review highlights the broad agricultural, industrial, and biomedical applications of chitinases and their crucial role in promoting environmental sustainability and advancing bio-based industrial processes.
A holistic perspective on the efficiency of microbial enzymes in bioremediation process: Mechanism and challenges: A review Medhat A. Abu-Tahon, Manal M. Housseiny, Heba I. Aboelmagd, Nada Daifalla, May Khalili, Adaugo C. Isichei, Abeer Ramadan, Ahmed M. Abu El-Saad, Nermien H. Seddek, Doaa Ebrahim, Yahia H. Ali, Intisar K. Saeed, Hind A. Rikabi, Lina Eltaib International Journal of Biological Macromolecules, 2025 Industrial activities, pharmaceutical contaminants, excessive agricultural inputs, and improper waste disposal have contributed to the widespread pollution of soil and water. Traditional remediation techniques, while effective, often generate secondary waste and are economically unfeasible. In contrast, microbial bioremediation offers a sustainable and cost-effective alternative by utilizing microorganisms and their enzymatic systems to degrade and detoxify pollutants. This review investigates the potential of microbial enzymes in remediation strategies for removing heavy metals and pharmaceutical contaminants from polluted environments. It analyzes the fundamental mechanisms by which microorganisms sequester and degrade these pollutants, emphasizing the enzymatic processes that facilitate their breakdown. Furthermore, it explores key microbial factors influencing bioremediation efficiency, including microbial diversity and environmental conditions. Additionally, it examines the challenges associated with scaling these bioremediation strategies for global environmental applications and provides insights for future research and implementation.
In-ovo injection of Bacillus subtilis, raffinose, and their combinations enhances hatchability, gut health, nutrient transport- and intestinal function-related genes, and early development of broiler chicks Abdelrazeq M. Shehata, Nermien Helmy Seddek, Tarek Khamis, Shaaban S. Elnesr, Hela Rached Nouri, Hibah M. Albasri, Vinod Kumar Paswan Poultry Science, 2024 An experiment was conducted to assess the response of chicks to in-ovo injection of Bacillus subtilis (probiotic), raffinose (prebiotic), and their combinations. The study used 1,500 embryonated eggs allotted to 10 groups/ 6 replicates (150 eggs/group). The experimental treatments were: 1) un-injected control (NC); 2) sham (sterile distilled water) (PC); 3) probiotic 4 × 10<sup>5</sup>CFU/egg (LBS); 4) probiotic 4 × 10<sup>6</sup>CFU/egg (HBS); 5) prebiotic 2 mg/egg (LR); (6 prebiotic 3 mg/egg (HR); 7) probiotic 4 × 10<sup>5</sup>CFU + prebiotic 2 mg/egg (LBS+LR); 8) probiotic 4 × 10<sup>5</sup>CFU + prebiotic 3 mg/egg (LBS+HR); 9) probiotic 4 × 10<sup>6</sup>CFU + prebiotic 2 mg/egg (HBS+LR); and 10) probiotic 4 × 10<sup>6</sup>CFU + prebiotic 3 mg/egg (HBS+HR). Results showed that in-ovo inclusion of Bacillus subtilis, prebiotic, and their combinations improved hatchability, yolk-free chick weight, and chick weight compared to the control group. Moreover, the in-ovo treatment reduced residual yolk weight on the day of hatch compared to the control group. Different levels of in-ovo B. subtilis alone or combined with raffinose significantly (P ≤ 0.001) reduced total bacterial count and total yeast and mold count compared to the negative control group. Total coliform and E. coli decreased significantly (P ≤ 0.001) in groups treated with probiotics, prebiotics, and synbiotics with different doses during incubation compared to those in the control. Clostridium spp. was not detected in the groups injected with B. subtilis alone or combined with raffinose. In-ovo probiotics and synbiotics (LBS+LR & LBS+HR) significantly (P ≤ 0.001) increased ileal villus length compared to other groups. In-ovo treatment increased mRNA expression of JAM-2 compared to the control group. The fold change significantly increased in group LBS+HR for genes MUC-2, OCLN, VEGF, SGLT-1, and EAAT-3 compared to the negative control. In conclusion, in-ovo injection of a low dose of B. subtilis plus a high or low dose of raffinose can positively affect hatching traits, cecal microbial populations, intestinal histomorphometry, nutrient transport- and intestinal function-related genes, and chick quality of newly hatched broiler chicks.
The effect of using fresh farmyard manure (animal manure) on the severity of Fusarium verticilioides in soil, root, stem, and kernels as well as lodging and borer incidence of maize plants Samar S. A. Elsayed, Mohamed D. Sehsah, Moufida A. Oueslati, Omar M. Ibrahim, Salem Hamden, Nermien H. Seddek, Heba I. Abo-Elmagd, Dalal Hussien M. Alkhalifah, Mohamed S. Sheteiwy, Hamada AbdElgawad, Mohamed T. El-Saadony, Amira M. El-Tahan Frontiers in Plant Science, 2023 Fusarium verticillioides, an important maize pathogen, produce fumonisins, causes stalk rot and consequentially reduce crop growth and yield. Therefore, herein we aimed to evaluate the potential use of two farmyard soil organic manures, i.e., fresh (5-6 days old) and stored (5-6 months old) organic manure, to manage F. verticillioides infections as well as borer incidence and lodging in maize plants. After 30, 60, and 90 days of sowing, samples of soil, roots, and stems were collected to isolate F. verticillioides. Moreover, we estimated ear and kernel rot induced by F. verticillioides at the final harvest. Fresh organic manure treatment increased infection rates of F. verticillioides in soil, roots, stem and kernels compared to the control treatment. In contrast, stored organic manure plots treatments decrease F. verticillioides frequency. At 90 days after sowing, stored organic manure suppressed the survival of F. verticillioides, which reduced the F. verticillioides incidence percent. These results were similar to the effect of herbicides-and insecticide-treated plots demonstrated, which show a significant decrease in F. verticillioides incidence rates. Mycological analysis on symptomless kernels revealed a higher % of pathogen infection in opened husks variety (Balady) than closed husks variety (SC10). Compared with stored organic manure, the stem borer incidence and lodging percentage were the highest in fresh organic manure plots. Finally, these results demonstrated that storing organic manure within five to six months as farmyard manure led to high-temperature centigrade within organic manure, thereby destroying spores of F. verticillioides, whereas fresh organic manure did not.
Clinical outcomes and prevalence of hepatitis e virus (Hev) among non-a-c hepatitis patients in Egypt Ibrahim M Sayed, Mohamed A El-Mokhtar, Mahmoud Abdel Rahman Mahmoud, Amal A Elkhawaga, Shereen Gaber, Nermien H Seddek, Lobna Abdel-Wahid, Ahmed M Ashmawy, Enas Ahmed Reda Alkareemy Infection and Drug Resistance, 2021 Background Hepatitis E virus (HEV) is an emerging infectious agent that causes acute hepatitis in developing and developed countries. Diagnosis of HEV infection has not been routinely done in Egyptian hospitals, and clinicians do not prescribe ribavirin (RBV) for acute hepatitis cases of unknown etiology (AHUE). We aimed to screen patients with AHUE for the presence of HEV markers and to determine the complications associated with HEV infection. Patients and Methods HEV markers (anti-HEV IgM, anti-HEV IgG, and HEV RNA) were assessed in patients with AHUE (n=300) admitted to Assiut University Hospitals. RT-qPCR was used to detect the viral load and sequencing analysis was carried out to determine the genotype of the detected viruses. Phylogenetic tree was constructed to evaluate the genetic relatedness between the isolates. Laboratory parameters and the outcomes of infection were determined. Results Acute HEV infection (AHE) was detected in 30 out of 300 (10%) of AHUE patients. Anti-HEV IgM, HEV RNA, and anti-HEV IgG were reported in 83%, 50%, and 43% of the samples, respectively. HEV RNA load ranged from 5×102 IU/mL to 1.1×104 IU/mL. Sequencing of the isolated viruses revealed that five viruses belong to HEV-1 and one isolate belongs to HEV-3 with high homology to the virus recently isolated from the cow and goat milk in the Egyptian villages. Although previous reports showed that attenuated HEV isolates were circulating in Egypt, four out of 30 patients (13%) developed coagulopathy and hepatic encephalopathy and died due to fulminant hepatic failure (FHF) within 3–6 weeks of hospitalization. Age, malignancy, and a history of pre-existing liver diseases were a risky factor for FHF development. Conclusion AHE is common in Upper Egypt. Older patients with malignancy and/or a history of liver diseases are risky. HEV diagnosis and treatment become pivotal in Egyptian hospitals to reduce the fatality rate and they should start urgently and promptly.
Evaluation of antimicrobial, antioxidant and cytotoxic activities and characterization of bioactive substances from freshwater blue-green algae Nermien H. Seddek, Mustafa A. Fawzy, W. El-said, M. Marwa, Ragaey Global Nest Journal, 2019 <p>Organic solvent extracts of three cyanobacterial species (Anabaena oryzae, Oscillatoria sp. and Stigonema ocellatum) were tested for antimicrobial activity against human pathogenic fungal and bacterial strains as well as for antioxidant and cytotoxic activity against human breast adenocarcinoma (MCF-7). The acetone extract of Anabaena oryzae was found to be the most active one against tested fungal and bacterial strains. It showed a maximum antimicrobial activity against Serratia marcescens and Candida albicans. The methanol extract of Oscillatoria sp. exhibited the best total antioxidant capacity compared to the other solvents and algal species. Acetone and methanol extracts of Anabaena oryzae exhibited high toxicity against MCF-7 cell line with IC50 of 45.1 and 44.4 µg/L, respectively. Acetone was the best solvent for extracting the active material. The acetone extracts were characterized by Gas Chromatography Mass Spectrophotometer (GC–MS) to identify the compounds responsible for such activities. Pharmaceutical important compounds in the acetone extract of cyanobacterial species like diacetone alcohol, acetic acid butyl ester mesityl oxide and heptadecane were present as a major component. These results indicate that extracts of studied cyanobacterial species exhibited appreciable antimicrobial, antioxidant and cytotoxic activity and could be a source of valuable bioactive materials for health products.</p>
In vitro-exploration of fungal endophytes of Egyptian cynara scolymus L. (artichoke) and investigation of some their bioactive potentials A. Thabet Global Nest Journal, 2019 <p>Plant-associated microorganisms, especially endophytic fungi, represent an untapped resource for the discovery of biologically active natural products. The objectives of this study were to isolate, identify endophytic fungi, and produce their bioactive metabolites from the leaves of two varieties of Egyptian artichoke namely: French Hyrious and Egyptian Baladi. In addition, assess of their total antioxidant capacity (TAC), total phenolic content (TPC) and total flavonoid content (TFC). The results of this novel study show a total of 35 endophytic fungal species belonging to 14 genera were isolated from both artichoke leaves with gross total counts of colonizing endophytic fungi ranged from 71 to 123 cfu which is matching 78.89% to 136.67% of colonization frequency. All taxa recovered were assigned to Ascomycetes. In addition, there is high species richness and diversity indices of endophytic filamentous fungi in the leaves Baladi Artichoke as compared to its French rival. &nbsp;<em>Alternaria alternata</em> were found to be the most frequently isolated dominant species. The TAC, TPC and TFC of the fungal cultures ranged from 163 to 681 mgAAE/gDW, 10.38 to 40.30 mgGAE/ gDW, and 13.92 to 173.55 mgQE/gDW, respectively. Furthermore, LC-ESI-MS/MS confirmed the presence of 1,3-dicaffeoylquinic acid and 1,5-dicaffeoylquinic acid in the methanolic extract of <em>A. alternata.</em> Hence, this novel study suggested that the metabolites produced by endophytic fungi associated with Egyptian artichoke could be explored as an economic and potential natural resources with diverse pharmaceutical and biological activities.</p>
First detection of Neoscytalidium dimidiatum associated with canker disease in Egyptian Ficus trees O. A. Al-Bedak, R. A. Mohamed, Nermien H. Seddek Forest Pathology, 2018 Summary In September 2013, a canker disease of Ficus nitida and F. benjamina was reported for the first time in Assiut governorate, Egypt. Infected samples were collected from various locations. Pure cultures of a fungus were isolated on potato dextrose agar at 25°C from diseased plants. Morphological investigation and DNA sequencing showed that the causal agent was Neoscytalidium dimidiatum . A pathogenicity test conducted using 2‐year‐old plants of each host gave 70%–80% infection, and the pathogen was reisolated from the inoculated plants. A pure culture of N. dimidiatum was deposited in the culture collection of the Assiut University Mycological Centre ( AUMC ) under the code AUMC 9293 and the ITS sequence was placed in NCBI under accession number KX985929 .
RECENT SCHOLAR PUBLICATIONS
Microbial chitinases—Production, characterization, purification and their biotechnological and therapeutic applications: An integrated review MA AbuTahon, HI Aboelmagd, MM Housseiny, AM Abdel‐Mageed, ... BioResources 21 (1), 2587 , 2026 2026 Citations: 1
A holistic perspective on the efficiency of microbial enzymes in bioremediation process: Mechanism and challenges: A review MA Abu-Tahon, MM Housseiny, HI Aboelmagd, N Daifalla, M Khalili, ... International Journal of Biological Macromolecules 308, 142278 , 2025 2025 Citations: 33
In-ovo injection of Bacillus subtilis, raffinose, and their combinations enhances hatchability, gut health, nutrient transport-and intestinal function-related genes, and early … AM Shehata, NH Seddek, T Khamis, SS Elnesr, HR Nouri, HM Albasri, ... Poultry Science 103 (11), 104134 , 2024 2024 Citations: 9
The effect of using fresh farmyard manure (animal manure) on the severity of Fusarium verticilioides in soil, root, stem, and kernels as well as lodging and borer … SSA Elsayed, MD Sehsah, MA Oueslati, OM Ibrahim, S Hamden, ... Frontiers in Plant Science 13, 998440 , 2023 2023 Citations: 17
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In vitro-exploration of fungal endophytes of Egyptian Cynara scolymus L.(artichoke) and investigation of some their bioactive potentials HS Nermien, A Thabet, AA Markeb, D Sayed, N El-Maali Glob. NEST J 21, 296-308 , 2019 2019 Citations: 5
Bioactive compounds and antioxidant activity of the non-edible parts of two taxa from Egyptian Artichoke (Cynara scolymus L.) A Thabet, AA Markeb, NH Seddek, D Sayed, NA El-Maali Assiut Univ J Chem 48, 1-15 , 2019 2019 Citations: 1
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First detection of Neoscytalidium dimidiatum associated with canker disease in Egyptian Ficus trees OA Al‐Bedak, RA Mohamed, NH Seddek Forest Pathology 48 (2), e12411 , 2018 2018 Citations: 38
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Activity of some natural oils on dermatophytes isolated from assuit University hospitals SG El Gendy, NH Seddek, SM Mohammed The Egyptian Journal of Medical Microbiology (EJMM) 25 (2) , 2016 2016 Citations: 7
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Fungal flora contaminating Egyptian Ras cheese with reference to their toxins and enzymes NH Seddek, NH Gomah, DM Osman Food Science and Technology 4 (4), 64-68 , 2016 2016 Citations: 14
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Antibacterial and antifungal activities of extract of cyanobacteria Anabaena oryzae and Spirulinaplatensis NHSF M.A. Journal for Advanced Research in Applied Sciences 1 (1), 10-19 , 2014 2014 Citations: 3
MOST CITED SCHOLAR PUBLICATIONS
Evaluation of antimicrobial, antioxidant and cytotoxic activities and characterization of bioactive substances from freshwater blue-green algae. NH Seddek, MA Fawzy, WA El-Said, MMR Ahmed 2019 Citations: 64
Clinical outcomes and prevalence of hepatitis E virus (HEV) among non-AC hepatitis patients in Egypt IM Sayed, MA El-Mokhtar, MAR Mahmoud, AA Elkhawaga, S Gaber, ... Infection and Drug Resistance, 59-69 , 2021 2021 Citations: 42
First detection of Neoscytalidium dimidiatum associated with canker disease in Egyptian Ficus trees OA Al‐Bedak, RA Mohamed, NH Seddek Forest Pathology 48 (2), e12411 , 2018 2018 Citations: 38
A holistic perspective on the efficiency of microbial enzymes in bioremediation process: Mechanism and challenges: A review MA Abu-Tahon, MM Housseiny, HI Aboelmagd, N Daifalla, M Khalili, ... International Journal of Biological Macromolecules 308, 142278 , 2025 2025 Citations: 33
The effect of using fresh farmyard manure (animal manure) on the severity of Fusarium verticilioides in soil, root, stem, and kernels as well as lodging and borer … SSA Elsayed, MD Sehsah, MA Oueslati, OM Ibrahim, S Hamden, ... Frontiers in Plant Science 13, 998440 , 2023 2023 Citations: 17
L-ASPARAGINASE PRODUCTION Y B ENDOPHYTIC FUNGI ISOLATED FROM WITHANIA SOMNIFERA IN EGYPT AM Moharram, AA Zohri, NH Seddek 2016 Citations: 16
Optimization of kojic acid production conditions from cane molasses using Plackett-Burman design RAH Abdel-Naser A. Zohri, Ghada Abd-Elmonsef Mahmoud, Nermien H. Saddek European Journal of Biological Research 8 (2), 56-59 , 2018 2018 Citations: 15
Fungal flora contaminating Egyptian Ras cheese with reference to their toxins and enzymes NH Seddek, NH Gomah, DM Osman Food Science and Technology 4 (4), 64-68 , 2016 2016 Citations: 14
Production of Kojic Acid by Endophytic Fungi Isolated From Medicinal Plant in Egypt AAZNHS A. M. Moharram International Invention Journal of Biochemistry and Bioinformatics 3 (3), 28-31 , 2015 2015 Citations: 14
In-ovo injection of Bacillus subtilis, raffinose, and their combinations enhances hatchability, gut health, nutrient transport-and intestinal function-related genes, and early … AM Shehata, NH Seddek, T Khamis, SS Elnesr, HR Nouri, HM Albasri, ... Poultry Science 103 (11), 104134 , 2024 2024 Citations: 9
Activity of some natural oils on dermatophytes isolated from assuit University hospitals SG El Gendy, NH Seddek, SM Mohammed The Egyptian Journal of Medical Microbiology (EJMM) 25 (2) , 2016 2016 Citations: 7
In vitro-exploration of fungal endophytes of Egyptian Cynara scolymus L.(artichoke) and investigation of some their bioactive potentials HS Nermien, A Thabet, AA Markeb, D Sayed, N El-Maali Glob. NEST J 21, 296-308 , 2019 2019 Citations: 5
Antibacterial and antifungal activities of extract of cyanobacteria Anabaena oryzae and Spirulinaplatensis NHSF M.A. Journal for Advanced Research in Applied Sciences 1 (1), 10-19 , 2014 2014 Citations: 3
Microbial chitinases—Production, characterization, purification and their biotechnological and therapeutic applications: An integrated review MA AbuTahon, HI Aboelmagd, MM Housseiny, AM Abdel‐Mageed, ... BioResources 21 (1), 2587 , 2026 2026 Citations: 1
Bioactive compounds and antioxidant activity of the non-edible parts of two taxa from Egyptian Artichoke (Cynara scolymus L.) A Thabet, AA Markeb, NH Seddek, D Sayed, NA El-Maali Assiut Univ J Chem 48, 1-15 , 2019 2019 Citations: 1
The effect of using fresh farmyard manure (animal manure) on the severity of Fusarium verticilioides in soil, root, stem, and kernels as well SSA Elsayed, MD Sehsah, MA Oueslati, OM Ibrahim, S Hamden, ... 2023
Potential of yeasts as biocontrol agent of fungal growth on the surface of Ras Cheese NHSDMO Nanis H. Gomah Indian Journal of Dairy Science 70 , 2017 2017
Antileukemic agents produced by Adiantum capillus-veneris L. fungal endophytes AAZAM Moharram The first International conference in Multidisciplinary Reseach , 2015 2015
