Youssuf Gherbawy

• Professor
• Professor at South Valley University

Cereals and other crops are often heavily laden with Fusarium species and are mostly contaminated with mycotoxins that have a serious effect on public health. Twenty‐six strains of Fusarium were collected from different crops in the Qena Governorate. According to phylogenetic analysis of Translation Elongation Factor 1 alpha sequences, the collecte...

Turmeric (Curcuma longa) is a spice widely used worldwide. It has been used in the treatment and prevention of diseases since ancient times. During harvesting and storage, turmeric is exposed to contamination by different fungi that are responsible for mycotoxins production. Mycobiota and mycotoxins associated with turmeric spices samples were scre...

Poultry feeds with cereal grain-based constituents are vulnerable to fungal contamination during the processing and storage stages. A total of 100 samples of compound poultry feedstuffs were collected from the cities of Riyadh, Alhassa, Qassim, and Jeddah in Saudi Arabia. A quantitative enumeration of fungal colony-forming units (CFUs) was performe...

At a global scale, grains and poultry feeds are the primary sources of feed. Due to their considerable significance, any fungi capable of infecting these feedstuffs can pose a threat to both food safety and security. Fusarium spp. are a highly significant group of organisms. Fumonisins (FBs), deoxynivalenol (DON), trichothecene (T-2), and zearaleno...

Contamination of agricultural and industrial products by Aspergillus section Circumdati becomes a true problem, especially, because a lot of species in this section can yield ochratoxins and other toxins. In this study, morphological criteria and partial calmodulin gene were used to identify 34 strains belonging to Aspergillus section Circumdati is...

Increased frequencies of Aspergillus section Flavi and aflatoxins in cereal grains have been seen in recent years due to changes in climate circumstances, such as high temperatures and drought. To assess the microbiological risks of contamination, it is critical to have a reliable and accurate means of identifying the fungi. The main goal of this s...

A diverse population of fungi colonizes human hair and skin due to millions of years of functional integration and mutual adaptation. The human body, with its fungal communities, forms a complex entity. Microbial imbalance is promoted by instabilities in the host–mycobiota interaction system, which can be related to the development of various disea...

The objectives of the study identify the fungal species from guava leaves symptomatic with leaf spots. Six fungal species (Alternaria atra, Botryotrichium verrucosum, Cochliobolus specifer, Drechslera halodes, Humicola grisea and Stachybotrys chartarum) were isolated from infected guava leaves by the direct plate method on PDA medium at 28°C. Patho...

Aim: Whip smut of sugarcane is the most serious and widely spread disease of sugarcane and causes a significant reduction in cane quantity and quality. This work aimed to assess the macroscopic and microscopic characteristics and the variability between isolates of Sporisorium scitamineum causal agent of smut in sugarcane. Materials and Methods: Th...

Nervous necrosis virus (NNV) is the causative agent of viral nervous necrosis in freshwater and marine fishes. In this study, NNV circulating among wild and farmed Nile tilapia ( Oreochromis niloticus ) was genetically and morphologically characterized using reverse transcription polymerase chain reaction (RT-PCR), sequencing analysis, and transmis...

Potato (Solanum tuberosum L.) is one of the known five crops cultivated throughout the world after corn, barley, cereals, rice, and wheat, due to its content of high carbohydrates. In developing countries, potatoes are especially had valuable contents as a rich source of starch, vitamins C and B6, and essential amino acids. Fusarium solani species...

Stachybotrys (S.) chartarum had been related to dangerous health problems in animals and humans that take place when exposure to S. chartarum toxins. S. chartarum had been isolated from various substrates, ranging from inappropriately stored feed and culinary herbs to damp buildings. To evaluate the pathogenic potential of isolates, it is essential...

Vicia faba (faba bean) is one of the most significant leguminous crops. The faba bean is specialized by maximum nutritional value, in energy and protein content, which leads it to be suitable for food and feed production. Diseases caused with fungi are amongst the biotic factors responsible for decreasing in faba bean yields. In this work, Cladospo...

Penicillium is one of the most important postharvest pathogens of citrus fruits worldwide. It induces blue or green mold disease, a decay that can lead to significant economic losses during storage. Based on internal transcribed spacer (ITS) sequences, seven Penicillium species and one closely related Talaromyces variabilis were identified from 30...

Potato ( Solanum tuberosum L.) is among the top five crops growing worldwide following cereals, rice, wheat, barley and corn due to its high carbohydrate content and adaptability. Potatoes are particularly valued in developing countries as a rich source of vitamins C and B6, starch and essential amino acids. Fusarium solani species complex (FSSC) i...

Potato (Solanum tuberosum L.) is among the top five crops growing worldwide following cereals, wheat, rice, corn and barley due to its high carbohydrate content and adaptability. Potatoes are particularly valued in developing countries as a rich source of starch, vitamins C and B6 and essential amino acids. Fusarium solani species complex (FSSC) is...

Potato ( Solanum tuberosum L.) is among the top five crops growing worldwide following cereals, rice, wheat, barley and corn due to its high carbohydrate content and adaptability. Potatoes are particularly valued in developing countries as a rich source of vitamins C and B6, starch and essential amino acids. Fusarium solani species complex (FSSC) i...

Corn, sorghum and wheat grains are used as livestock feed in the world. Identification of black aspergilli associated with these grains is necessary to make sure of the safety of the grains because its occurrence is an indicator of mycotoxin production. Forty-five isolates were isolated from the samples collected from Upper Egypt's markets and iden...

Citrus is the most important crop in Upper Egypt. 150 infected samples were collected from citrus samples (Navel orange, Tangerine and Lemon) in Upper Egypt, 50 samples from each fruit. Twenty-two isolates representing three species of Alternaria belong to A. sect. Ulocladioides and A. sect. Ulocladium were isolated on dichloran chloramphenicol- pe...

Chaetomium species are saprophytic fungi, havethe ability to degrade cellulose with hydrolytic enzymes. Hydrolytic enzymes are a cluster of enzymes, which have the flexibility of breaking down complicated molecules into smaller molecules. The objective of this study was to clarify the genetic diversity among the isolated Chaetomium population by us...

Fungal and mycotoxins contamination of food and poultry feeds can occur at each step along the chain from grain production, storage, and processing. A total of 200 samples comprising of mixed poultry feedstuffs (n = 100) and their ingredients (n = 100) were collected from Riyadh, Alhassa, Qassium, and Jeddah cities in Saudi Arabia. These samples we...

Ten strains of Fusarium solani were isolated on Potato Dextrose Agar medium from rotten potato tubers marketed in Upper Egypt region. The identification of collected isolates was carried out by morphological criteria and species-specific primer, TEF-Fs4f and TEF-Fs4r was used to confirm the identification. Genetic diversity of the collected isolate...

Chaetomium globosum is known as a potential biocontrol indicator against various soil and seedborne pathogens. Precise data are necessary for population monitoring of C. globosum for its effective use in agriculture. A sequence‐characterized amplified region marker has been applied for the detection of this biocontrol agent, which will help to dete...

Potato (Solanum tuberosum L.) is an important crop which holds promise for food security considering the global population growth rate. Fusarium dry rot is one of the most significant diseases of potato. To build up strategies for the control of this disease, it ought to be made primarily a correct diagnosis and identification of the pathogen. A to...

Mycotoxins are toxic metabolites mainly produced by Aspergillus spp. fungi. Further fungal characterization and mycotoxin estimation in feed are crucial measures for animal health and safety. The aim of this study was to identify and characterize mycotoxin-producing fungi in poultry feed. Forty poultry ration samples were collected and were subject...

Twenty-six fungal species belonging to 10 genera were collected from 40 beef luncheon samples marketed in the Qena city on Czapek–Dox agar at 28 °C. A. section Nigri and A. flavus were the most prevalent species among isolated fungi; they were contaminating 65% and 50% of the luncheon samples. According to the phylogenetic analysis using β-tubulin...

Aspergillus and their aflatoxins contaminations were studied in sixty poultry and animal feedstuff samples collected from the western region (Jeddah, Makkah and Taif cities) from Saudi Arabia. Fourteen species of Aspergillus were isolated and identified in the present investigation using Potato Dextrose Agar (PDA) at 27ºC. The identification of iso...

Phenolic compounds are dominant pollutants in terrestrial and freshwater environmental that have toxic effects on living organisms at low concentrations, because it has the ability to persist in the ecosystem. So bio-removal is a good technique that employs the metabolic potential of microorganisms to clean up the environmental pollutants and turne...

Fruits are one of the most important agricultural products that supply the body with vitamins and essential minerals elements, but it is contaminated by fungi during the period of growth, harvesting and storage. A. niger is one of the species that grows on the fruit during the period of storage, and secretes mycotoxins especially ochratoxin A. This...

Dear Colleagues, On behalf of the Organizing Committee I would like to invite you to attend the 4th International Conference for Environmental Studies that will be held in South Valley University, Hurghada, Egypt, from 23 to 25 October 2018. The South Valley University, Egypt, will be pleased to welcome as many colleagues from worldwide as possible...

We studied mycotoxigenic fungi contaminating stored wheat grain, measured the toxins they secreted, and assessed their harmfulness. We focused on one common genus Alternaria, and chose 19 isolates representing A. compacta to study how different strains differed in their mycotoxin secretion and toxicity. Toxicity was assessed in a bioassay with a mo...

The mycological profile of the retail wheat flour selling in different markets at Jeddah (Kingdom of Saudi Arabia) was studied. The most common genera were Aspergillus (isolated from 70% of the tested samples), Penicillium (30%), Eurotium (14%), and in a lesser extent Fusarium (20%) and Alternaria (18%). Twenty-nine strains of Aspergillus flavus we...

Alternaria alternata is the most common fungal pathogen of tomatoes in Upper Egypt. Morphological identification of this fungus is challenging; therefore, this study searched for new classification tools based on molecular techniques. Using a dilution plating method, 67 strains of A. alternata were isolated from 34 samples of rotten tomato fruits r...

Cardamom is added to Arabic coffee the most popular drink in Saudi Arabia, and used as an food additives in many dishes in Saudi kitchen, the mycological profile and mycotoxin contaminated of cardamom selling in different markets in western regio. (KSA) was studied. Using morphological criteria and internal transcribed space (ITS) region sequencing...

Phenolic compounds are dominant pollutants in terrestrial and freshwater environmental that have toxic effects on living organisms at low concentrations, because it has the ability to persist in the ecosystem. So bio-removal is a good technique that employs the metabolic potential of microorganisms to clean up the environmental pollutants and turne...

Camel is a very hardy animal and well adapted to harsh climatic conditions of desert. It is the principle domestic animal in Saudi Arabia. Fasciola sp. considered as one of the most common gastrointestinal helminthes in camels in Saudi Arabia. Understanding genetic structure and status of genetic variation of camels Fasciola spp. has important impl...

Alternaria species produce several mycotoxins that are of particular health concern. The natural occurrence of three Alternaria toxins; alternariol (AOH), alternariol methyl ether (AME), and tenuazonic acid (TA) in pomegranate fruit was considered. A. alternata and A. tenuissima were identified by analysis of partial sequence of ITS-region. All stu...

The aflatoxigenic abilities of 64 and 17 isolates of Aspergillus flavus and A. parasiticus isolated from poultry and animal feedstuff samples collected from the western region of Saudi Arabia were studied. Thirty-three (51.6%) and 13 (76.5%) isolates of A. flavus and A. parasiticus, respectively, were aflatoxigenic. The ranges of aflatoxins in A. f...

Background: Endophytic fungi, which have been reported in numerous plant species, are important components of the forest community and contribute significantly to the diversity of natural ecosystems. Objectives: The current study aimed to evaluate and characterize, at the molecular level, the diversity and antimicrobial activities of endophytic...

Background: The rise of CTX-M extended spectrum β-lactamase (ESBLs)-producing E. coli in non-human sources is a growing concern of public health. Understanding the extent of public health risk attributed to CTX-M type ESBLs-producing strains from different sources is critical for effective control.Objective: This study focuses on detection and...

High sulfur content of crude oil leads to poor quality of oil products and many other negative consequences such as corrosion, catalyst poisoning and environmental pollution. Saudi Arabia is seeking to reduce sulfur content in diesel and gasoline to 10 ppm and to lower benzene content in gasoline to 1%. Biotechnological processes such as biodesulfu...

Capsicum annuum (bell and chili peppers) is one of those vegetable crops growing in the warm areas. Pepper production conditions require drying fruits in most cases by the sun light. During drying processes, this crop is exposed to contamination with microorganisms, especially fungi. In this article, mycobiota of 60 samples of different chill produ...

This study investigated fungal spoilage of fruits and vegetables in Saudi Arabia. Activities of cell wall degrading enzymes in fungal isolates were measured. We evaluated the fungicidal activities of chitosan against spoilage fungi. Thirty-three fungal species belonged to 21 fungal genera were collected during this study. ITS sequencing results sho...

Onion bulbs can become contaminated with various molds during the storage period, the most important causal agents being black aspergilli (Aspergillus section Nigri). Taxonomic studies have revealed that this group of Aspergillus contains many species that cannot be reliably identified using standard morphological methods. Therefore, it is necessar...

Capsicum annuum grows in warm areas. Pepper production conditions require the drying of fruits by sunlight. During the drying processes, the crop is exposed to contamination by microorganisms, especially fungi. In this article, the isolation of mycobiota from retail markets and food restaurants of Taif city was studied. Crushed chili showed a high...

The genus Chaetomium is a rich source of novel and bioactive secondary metabolites of great importance. To date, a variety of more than 200 secondary metabolites belonging to diverse structural types have been discovered. Fungal enzymes are used in food, beverages, confectionaries, textiles, and leather industries to simplify the processing of raw...

Fungal endophytes were isolated from the leaves of Calotropis procera (Apocynaceae) collected from Taif region (Saudi Arabia). Thirty-three different taxa were recovered. The overall foliar colonization rate was 35.1%. A total of 161 isolates were obtained and identified into 33 distinct operational taxonomic units based on the sequencing of the in...

This study was conducted to estimate the frequency of Cryptosporidium infections in Taif (Saudi Arabia). Stool samples from children under 10 years by modified Ziehl–Neelson staining and two PCR techniques were used for genotyping experiments. The microscopic examination showed that, eleven samples were positive for presence of Cryptosporidium. Wit...

Fungal endophytes were isolated from twigs of Juniperusprocera (Cupressaceae) collected from Taif region (Saudi Arabia). Twenty-six different taxa were recovered. The overall foliar colonization rate was 36%. A total of 144 isolates were obtained and identified into six distinct operational taxonomic units based on the sequencing of the internal tr...

This paper describes the synthesis of a series of quinolines graphted with hydrazones, pyrazoles, pyridazine, phthalazine, triazepinone, semicarbazide, and thiomorpholide moieties and four metal complexes. These derivatives were screened against Fusarium oxysporum and the red palm weevil (RPW) Rhynchophorus ferrugineus Oliver (coleopteran: Curculio...

The presence of phorbol esters (PEs) with toxic properties limits the use of Jatropha curcas kernel in the animal feed industry. Therefore, suitable methods to detoxify PEs have to be developed to render the material safe as a feed ingredient. In the present study, the biological treatment of the extracted PEs-rich fraction with non-pathogenic fung...

This paper describes the synthesis of a series of quinolines graphted with hydrazones, pyrazoles, pyridazine, phthalazine, triazepinone, semicarbazide, and thiomorpholide moieties and four metal complexes. These de� rivatives were screened against Fusarium oxysporum and the red palm weevil (RPW) Rhynchophorus ferrugineus Oliver (coleopteran: Curcul...

Seed kernel from Jatropha curcas L. cannot be utilized as animal feed due to the presence of toxic phorbol esters. However, biological treatments may alleviate the concentration of phorbol esters to a safe level. In the present study, two fungal isolates obtained from garden soil and five endophytes from Achillea fragrantissima plant in Saudi Arabi...

Ninety isolates of Trichoderma (Teleomorph: Hypocrea) species and one isolate of Gliocladium viride (Tel. Hypocrea lutea) were isolated from soil samples collected from different locations in Taif city. Two soil samples cultivated with Purica granatum showed high incidences of isolates (13 and 12 isolates, respectively). Regions of nuclear rDNA, co...

The present work aimed to determine the bioactive compounds in two rosemary water extracts (RWE1 and RWE2) and to assess their antimicrobial, anti-adhesive and antibiofilm potentials against the food-related Bacillus and Pseudomonas species at concentrations; 4, 8, 12, 16 and 20 mg mL−1. Phenolic compounds and isoflavones in the RWEs were determine...

Recently, new strains of Fasciola demonstrated drug resistance, which increased the need for new drugs or improvement of the present drugs. Nanotechnology is expected to open some new opportunities to fight and prevent diseases using an atomic scale tailoring of materials. The ability to uncover the structure and function of biosystems at the nanos...

As an organ for reserve and propagation, the tuber grows underground and is in contact with soil-borne microorganisms, making it potentially exposed to blemishes. Therefore, the objective of this study was the possibility of using some modern methods of molecular diagnostics and detection of the presence of fungal contaminants in potato blemishes i...

Aflatoxins are commonly found in cereals worldwide and bring significant threats to the food industry and animal food production. Among a collection of aflatoxin-degradative endophytic bacteria isolated from grains of corn plant, the strain TUBF1 was selected based on its high-ability to utilize aflatoxin B1 (AFB1) (10 μg/mL) as the sole carbon sou...

As an organ for reserve and propagation, the tuber grows underground and is in contact with soil-borne microorganisms, making it potentially exposed to blemishes. Therefore, the objective of this study was the possibility of using some modern methods of molecular diagnostics and detection of the presence of fungal contaminants in potato blemishes i...

Pseudomonas Sp. Strain Bal1 was isolated isolated from Schistosome vector snails Bulinus Truncates. Strain Bal1 was identified as Pseudomonas putida using partial sequence of 16s rRNA. This strain was able to utilize a “Bayluscide” as a sole source of carbon and nitrogen. The degradation of “Bayluscide” by Bal1 strain is mediated by pBal1 (110 Kb)...

Accurate identification of Fasciola species, followed by biological and ecological characterization, is important with concern to the planning for field control. Because there are many variations in morphological characteristics, exact distinguishing of Fasciola species is usually difficult by simple traditional microscopic measurements and, theref...

Accurate identification of Fasciola species, followed by biological and ecological characterization, is important with concern to the planning for field control. Because there are many variations in morphological characteristics, exact distinguishing of Fasciola species is usually difficult by simple traditional microscopic measurements and, theref...

Defining enteric bacterial flora of clinically healthy captive houbara bustard and their resistance to antibiotics are an important step in understanding the epidemiology of bacterial diseases. These diseases may affect their population in captivity and so the environment after their release. The study amied to identify the intestinal bacterial flo...

In this study, the biosynthesis of silver nanoparticles using supernatant of Alcaligenes faecalis was described. UV– Vis absorption spectra showed the reduction of silver ions to silver nanoparticles with a surface Plasmon resonance (SPR) band centered at 455 nm. The TEM analysis revealed the formation of spherical, and monodispersed nanoparticles...

In this study, the biosynthesis of silver nanoparticles using supernatant of Alcaligenes faecalis was described. UV– Vis absorption spectra showed the reduction of silver ions to silver nanoparticles with a surface Plasmon resonance (SPR) band centered at 455 nm. The TEM analysis revealed the formation of spherical, and monodispersed nanoparticles...

In this study, among a collection of heavy metals resistant endophytic bacterial strains isolated from aquatic hyperaccumulator plant (Eichhornia crassipes), one plant growth promoting endophytic bacteria (PGPE), SVUB4 was selected for its ability to utilize 1-aminocyclopropane-1-carboxylic acid (ACC) as the sole N source and accumulate different h...

The study included collection of water samples (150 samples) from 10 different branches belonging to each water network in Jeddah City (Saudi Arabia). Samples included treated water (30 samples) and tap water in some hospitals (30 samples from cold water tap and 30 samples from hot water tap) and private houses (60 samples). According to results of...

Little is known about the bacterial communities associated with the rose plants inhabiting dry desert ecosystems. The aim of this study was to isolate and characterize endophytic bacteria from different organs of rose plant. Endophytic bacteria were observed in healthy roots, stems, leaves, and flowers of rose plant, with a significantly higher den...

Drinking water distribution networks are known to harbor microbial biofilms. The aim of the present work is to (i) identify the culturable bacteria presented in the drinking-water distribution network, (ii) investigate the ability of isolated bacteria to form biofilm under some environmental stress conditions and some liminating or removing treatme...

Thirty soil-isolates of Streptomyces were analyzed to determine their antagonism against plant-pathogenic fungi including Fusarium oxysporum, Pythium aristosporum, Colletotrichum gossypii, and Rhizoctonia solani. Seven isolates showed antifungal activity against one or more strain of the tested fungi. Based on the 16S rDNA sequence analysis, these...

This study aimed to determine the mycological profile of the retail date fruits distributed in different markets at Taif, Saudi Arabia. The presence of aflatoxins and ochratoxin A was also measured. Twenty-two fungal species belonging to 12 genera were isolated from 50 different date samples. Aspergillus flavus, A. niger, Penicillium chrysogenum, a...

Inoculating wheat (cv. Giza 164) with various Fusarium species had different effects on the catalase (CAT), peroxidase (POX) and ascorbate peroxidase (APX) activity in different plant tissues. The CAT activity induced in the shoots of wheat plants by some pathogens (F. merismoides, F. moniliforme, F. poae and F. sambucinum) was relatively higher th...

The diversity and beneficial characteristics of endophytic microorganisms have been studied in Plectranthus tenuiflorus medicinal plant. However, information regarding naturally occurring P. tenuiflorus plant associated endophytes among different organs of host is limited. Endophytic bacteria were isolated from root, stem, and leaves of P. tenuiflo...

Giardia parasite is prevalent endemically in Taif city. Infection is more prevalent in children under 5 years old and elderly people. The sickness is more intense in immunecompromised people. The disease is usually diagnosed by stool examination by the microscope, for the identification of the both trophozoite and cyst stages. Usually the disease i...

Dried grapes (raisin) may carry a significant mycological load contaminated via cultivation, postharvest processing practices, and drying processing. The contamination of raisin with fungi can accelerate spoilage or illness, if pathogens are present. Since raisins are used as food additives in many dishes in Saudi kitchen, there are healthy concern...

Dried grapes (raisin) may carry a significant mycological load contaminated via cultivation, postharvest processing practices, and drying processing. The contamination of raisin with fungi can accelerate spoilage or illness, if pathogens are present. Since raisins are used as food additives in many dishes in Saudi kitchen, there are healthy concern...

This study was carried out to describe the bacterial load and the occurrence of some disease-causing enteric bacteria on raw vegetables sold in Saudi markets. The study further aimed to analyze antibiotic resistance rates, production of extended-spectrum beta lactamase, and plasmid carriage among bacterial population of raw vegetables. Results reve...

Schistosomiasis is an important parasitic disease that infects humans. Among the main species of schistosomes infecting humans are Schistosoma mansoni and Schistosoma haematobium. The accurate diagnosis of these parasitic infections will improve the success of disease control and management. Many studies proved that Schistosoma exhibit variations n...

Fifty samples of skin ulcers were collected from the western region of Saudi Arabia Kingdom (Al Baha and Al Qasim) to study genotypic characterization of Cutaneous Leishmaniasis in this area. Thirty-six samples were recorded as Leishmania isolates. The same isolates were subsequently tested with fingerprinting with single arbitrary primers. The pri...

In Saudi Arabia, water resources are largely limited to groundwater, which is used both for drinking and agriculture. There is no surface water except for a few oases and no permanent streams. The contamination of this source possibly through wastewater, agriculture activities and wild birds as well as amphibians and reptiles that have access to we...

Giardia parasite is prevalent endemically in Taif city. Infection is more prevalent in children under 5 years old and elderly people. The sickness is more intense in immunecompromised people. The disease is usually diagnosed by stool examination by the microscope, for the identification of the both trophozoite and cyst stages. Usually the disease i...

Giardia parasite is prevalent endemically in Taif city. Infection is more prevalent in children under 5 years old and elderly people. The sickness is more intense in immunecompromised people. The disease is usually diagnosed by stool examination by the microscope, for the identification of the both trophozoite and cyst stages. Usually the disease i...