Tamer Thabit - Academia.edu (original) (raw)
Papers by Tamer Thabit
Foodborne Pathogens and Disease, Jun 1, 2014
The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing m... more The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing mycotoxins in animal feed. This study aimed to evaluate the β-D-glucan biopolymers as a mycotoxin binder for fumonisin (FUM) and deoxynivalenol (DON) toxins as well as their effect on the nutritional value of soybean, which is considered one of the important feed row materials. The evaluation was carried out using some toxigenic Fusarium isolates (Fusarium solani, F. oxysporum, and F. verticillioides) in vitro and in vivo. The FUM and DON levels were determined by immune affinity column. The F. verticillioides was the most toxigenic, followed by F. oxysporum and lastly F. solani, while secretion of DON toxin was determined to be greater than FUM with all the tested fungi. The effectiveness of β-D-glucan biopolymers on FUM and DON absorption was greater than clay and calcium propionate. In vivo, treating soybean seeds with β-D-glucan biopolymers led to reduction in the level of FUM and DON toxins in seeds artificially inoculated by F. verticillioides. β-D-glucan treatment also has a low effect on nutritional components of the seeds compared to untreated ones. In conclusion, this study found a new approach to reduce Fusarium mycotoxins in feed to an allowable safe limit and at the same time maintaining the nutritional value of these materials.
Journal of AOAC International, Sep 1, 2018
Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by diffe... more Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by different Fusarium species in many types of grains and food commodities. It has high damage impact on human and animal immune systems. Objective: This in vitro study aimed to evaluate the influence of silver nanoparticles (Ag-NPs) as an inhibitor for the DON toxin excreted from some Fusarium spp., which were isolated from barely, wheat, and corn grains. Methods: Ag-NPs were estimated on Minimum Inhibitory Concentration, using levels of 5, 25, 50, 75, and 100 ppm, while the effect on DON was conducted with ELISA. Tri13 and Tri7 primers were used to evaluate the impact of Ag-NPs on the DNA of tested toxigenic Fusarium isolates. Results: Results revealed that the relative density values (Rd, %) of the isolated Fusarium from barley, wheat, and corn grains were 41.27, 26.47, and 30.76%, respectively. The predominant fungus was F. graminearum and F. culmorum in wheat and barley, respectively. The maximum inhibition diameters used for concentrations were 0.5, 2.8, 3.2, 3.3, and 3.31 mm, respectively. The impact of Ag-NPs on genomic structure was limited. Results demonstrated that Ag-NPs have the ability to reduce the linear growth of Fusarium spp. and eliminate the DON toxin to 34.44, 34.60, and 34.89% at 50, 75, and 100 ppm. Conclusions: Ag-NPs are considered nontransgenic substances, and their impact on Fusarium DNA under tested concentrations has been neglected. Ag-NPs may work as an alternative to fungicides to reduce fungal growth and eliminate DON mycotoxins.
Journal of AOAC INTERNATIONAL, 2021
Background Cereal grains are an important for the nutrition of both humans and animals, and contr... more Background Cereal grains are an important for the nutrition of both humans and animals, and contribute to the nutrition cycle in different ways. Chemical contaminants are important to be monitored in food due to their direct effects on human health. Objective This work aimed to monitor some of the hazardous chemical contaminants i.e., organochlorines (OCs), pyrethroids, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in wheat and barley grains of European origin during 2019. Method Samples were collected consecutively during the season and the QuEChERS technique (quick, easy, cheap, effective, rugged, and safe) followed by GC-tandem mass spectrometry (GC-MS/MS) analysis was used in the extraction and cleaning up for all analyzed compounds. The method was verified, and a recovery study was performed at two spiking levels: 0.01 and 0.05 µg/g. RSD(%), LOD, and LOQ were calculated. Recovery ranged from 78.70–104.00% for all compounds at both levels at RSD 2...
Malathion in-vitro biodegradation study was conducted in liquid medium with five bacterial strain... more Malathion in-vitro biodegradation study was conducted in liquid medium with five bacterial strains labeled S1, S2, S3, S4 and S5 isolated from newly reclaimed agricultural soil. Malathion residues were measured at successive intervals until 30 days after incubation, paralleled with control samples. Malathion Recovery rate was performed at 0.1 and one mg kg -1 , achieved values were 91.30 and 98.70%, respectively, limit of detection (LOD) was 0.03 mg kg -1 while limit of quantification (LOQ) was 0.1 mg kg -1 . Malathion half-life values (RL 50 ) were 16.68, 20.27, 21.33, 12.72 and 12.49 days for S1, S2, S3, S4 and S5, respectively and control value was 27.50 days. No significant effect on malathion occurred with S2 (Bacillus amyloliquefaciens ) and S3 ( Staphylococcus sciuri ) treatments. S1 ( Pseudomonas aeruginosa ), S4 ( Bacillus pseudomycoides ) and S5 ( Bacillus licheniformis ) treatments showed significant effect that increased malathion degradation rate compared to control tre...
Journal of AOAC INTERNATIONAL, 2020
Wheat and barley grains are of the most important nutritional grains for human and animal which p... more Wheat and barley grains are of the most important nutritional grains for human and animal which play an essential role in the nutritional cycle by different ratios according to people nutritional habits. This work aimed to monitor 10 of the most important heavy metals in some European origin wheat and barley grains during the season of 2018. The measured elements Al, As, Cd, Co, Cr, Hg, Mo, Ni, Pb and V of the importance ecologically and biologically which may involve in many health disorder symptoms in human body. Moisture, protein and specific weight of grains have been checked. Samples were digested using microwave acid digestion and elements measured with ICP-MS/MS on He mode to increase sensitivity, lower the background and avoid interference. Method validation and verification were done thru spiking in two levels 2.0 and 10 ppb, then RSD, LOD and LOQ were calculated. Recoveries were >97% for all elements with both levels with RSD of < 7.6%. Results revealed that As, Cd, ...
Journal of AOAC International, Jan 3, 2018
Deoxynivalenol (DON) is one of the most important fungal mycotoxins excretedby different species ... more Deoxynivalenol (DON) is one of the most important fungal mycotoxins excretedby different species in many types of grains and food commodities. It has high damage impact on human and animal immune systems. This in vitro study aimed to evaluate the influence of silver nanoparticles (Ag-NPs) as an inhibitor for the DON toxin excreted from some spp., which were isolated from barely, wheat, and corn grains. Ag-NPs were estimated on Minimum Inhibitory Concentration, using levels of 5, 25, 50, 75, and 100 ppm, while the effect on DON was conducted with ELISA. and primers were used to evaluate the impact of Ag-NPs on the DNA of tested toxigenic Fusarium isolates. Results revealed that the relative density values (Rd, %) of the isolated from barley, wheat, and corn grains were 41.27, 26.47, and 30.76%, respectively. The predominant fungus was and in wheat and barley, respectively. The maximum inhibition diameters used for concentrations were 0.5, 2.8, 3.2, 3.3, and 3.31 mm, respectively. The...
Foodborne Pathogens and Disease, 2014
The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing m... more The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing mycotoxins in animal feed. This study aimed to evaluate the β-D-glucan biopolymers as a mycotoxin binder for fumonisin (FUM) and deoxynivalenol (DON) toxins as well as their effect on the nutritional value of soybean, which is considered one of the important feed row materials. The evaluation was carried out using some toxigenic Fusarium isolates (Fusarium solani, F. oxysporum, and F. verticillioides) in vitro and in vivo. The FUM and DON levels were determined by immune affinity column. The F. verticillioides was the most toxigenic, followed by F. oxysporum and lastly F. solani, while secretion of DON toxin was determined to be greater than FUM with all the tested fungi. The effectiveness of β-D-glucan biopolymers on FUM and DON absorption was greater than clay and calcium propionate. In vivo, treating soybean seeds with β-D-glucan biopolymers led to reduction in the level of FUM and DON toxins in seeds artificially inoculated by F. verticillioides. β-D-glucan treatment also has a low effect on nutritional components of the seeds compared to untreated ones. In conclusion, this study found a new approach to reduce Fusarium mycotoxins in feed to an allowable safe limit and at the same time maintaining the nutritional value of these materials.
American Journal of Environmental Protection, 2014
Foodborne Pathogens and Disease, 2012
Date palm (Phoenix dactylifera L.) is considered the main crop in deserts and arid areas such as ... more Date palm (Phoenix dactylifera L.) is considered the main crop in deserts and arid areas such as Saudi Arabia. Five Streptomyces species and other fungal species were isolated from date palm rhizosphere soil of several cultivars, such as Barhi, Khalas, Sullaj, and Sukkari, in the Ghat and El-Gouf regions. Streptomyces strains were isolated on Biolog universal growth agar medium and were identified following Biolog methods. The predominant Streptomyces isolated from this present survey was S. plicatus followed by S. rimosus, S. rutgersensus, and S. griseus. The number of soilborne fungi in the tested soil decreased with the increased number of isolated Streptomyces. There was a significant positive correlation between the date palm cultivar and the number of isolated Streptomyces. The in vitro effects of isolated Streptomyces species on some toxigenic fungi were also studied. Enzyme-linked immunosorbent assay, immunoaffinity column chromatography, and high-performance liquid chromatography were used to study the mycotoxins. The concentration of most of the tested mycotoxins was reduced significantly with the presence of the Streptomyces isolates. Results indicate that some Streptomyces isolates established in date palm rhizosphere have the ability to reduce production of mycotoxins of some toxigenic fungi; thus they have the potential of reducing the subsequent disease occurrence. Therefore they can be applied in wider range as biocontrol agents.
Soil in the Environment, 2013
Bacterial degradation trial for diazinon residues was performed using bacterial strains labeled a... more Bacterial degradation trial for diazinon residues was performed using bacterial strains labeled as S1, S2, S3, S4 and S5 isolated from newly reclaimed agricultural soil. Diazinon residues were determined at successive intervals untill 30 days after incubation in liquid medium containing bacteria paralleled with control samples. Diazinon recovery rate was carried out at 0.1 and 1 mg kg -1 levels; values were 95.77 and 101.12%, respectively, limit of detection (LOD) was 0.01 mg kg -1 , while limit of quantification (LOQ) was 0.03 mg kg -1 . Diazinon half-life values (RL50) were 9.36, 8.57, 12.71, 7.51 and 8.20 days for S1, S2, S3, S4 and S5, respectively, while control value was 14.06 days. No significant effect on diazinon occurred with S3 (Staphylococc us sciuri) treatment, while S1 (Pseudomonas aeruginosa), S2 (Bacillus amyloliquefaciens), S4 (Bacillus pseudomycoides) and S5 (Bacillus licheniformis) treatments showed significant effect, that increased diazinon degradation rate comp...
Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat ... more Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat crop is exposed to many fungal infections during the cultivation stages, some of which have the ability to secrete numbers of toxic secondary metabolites that threaten the quality of grains, consumer health, producer economics and global trade exchange. Fifty-four random samples were collected from wheat which originated from different countries. The samples included 14 of soft wheat to study the extent of their contamination with Deoxynivalenol (DON) and T-2 toxin by auto-ELISA technology and r-biopharm Microtiter plate. All samples were contaminated with DON toxin except one sample, and the contamination average ranged between 40.7 and 1018.8 µg kg-1. The highest contamination rates were in Lithuanian and the lowest in Indian wheat. Meanwhile the highest average level of T-2 toxin contamination was in Lithuanian wheat grains with a rate of 377.4µg kg-1 and the lowest in Polish wheat wi...
Journal of AOAC International, 2021
BACKGROUND Cereal grains are substantial in the nutrition process for both humans and animals and... more BACKGROUND Cereal grains are substantial in the nutrition process for both humans and animals and contribute to the nutrition cycle in different ways. Chemical contaminants are important to be monitored in food due to their direct effects on human health. OBJECTIVE This work aimed to monitor some of the hazardous chemical contaminants i.e., Organochlorines (OCs), Pyrethroids, Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in wheat and barley grains of some common European origin during 2019. METHODS Samples were collected consecutively during the season and the QuEChERS technique followed by GC-MS/MS analysis was used in the extraction and cleaning up for all analyzed compounds. The method was verified, a recovery study was performed at two spiking levels 0.01 and 0.05 µg/g. RSD%, LOD and LOQ were calculated. Recovery ranged from 78.70-104.00% for all compounds at both levels at RSD 2.16-11.76%. Fat, moisture, protein and specific weight contents of bot...
Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat ... more Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat crops are exposed to many fungal infections during their cultivation stages, some of which have the ability to secrete a number of toxic secondary metabolites that threaten the quality of the grains, consumer health, producer economics, and global trade exchange. Fifty-four random samples were collected from wheat which originated from different countries. The samples included 14 types of soft wheat to study the extent of their contamination with deoxynivalenol (DON) and T-2 toxin by auto-ELISA technology and r-biopharm microtiter plate. All samples were contaminated with DON toxin except one sample, and the values ranged between 40.7 and 1018.8 µg/kg−1. The highest contamination rates were in Lithuanian wheat and the lowest was in Indian wheat. Meanwhile, the highest average level of T-2 toxin contamination was in Lithuanian wheat grains with 377.4 µg/kg−1, and the lowest average was 11...
Journal of AOAC INTERNATIONAL
Medicinal Herbs is the old traditional way for many diseases treatment and now considered the fir... more Medicinal Herbs is the old traditional way for many diseases treatment and now considered the first natural source of the pharmaceutical active ingredients, so it is of the importance to focus on the hygiene of these plants as it should to be safe to consumption. This work aimed to monitor the common heavy and radioactive elements in some of the common used herbs namely Anise, Chamomile, Clover, Cumin, Coriander, Fennel, Roselle, Rosemary, Sage and Thyme. A total of 12 elements were measured including two radionuclides, Al, As, Cd, Hg, Co, Cr, Ni, Pb, Sr, Th, U and V. Heavy metal are ecologically and biologically important, which may involve in some health disorder symptoms in human body. Samples were digested with microwave digester and measurements have been done with ICP-MS/MS in Helium mode to increase sensitivity, lower the background and avoid interferences. Method validation and verification were done thru spiking process at 2.0 µg/kg level, then RSD, LOD and LOQ were calcula...
Journal of AOAC International
Phosphine is considered the main fumigant material used for long time for controlling insect pest... more Phosphine is considered the main fumigant material used for long time for controlling insect pests in stored grains. This research was focused on the determination of phosphine residues in cereal matrixes (mainly wheat and corn) after the fumigation process, using a new procedure developed to reduce the number of analytical steps and improve the chromatographic separation, identification, and quantitation of analyte, thus leading to enhanced total efficiency and sensitivity. This method, using gastight vials for extraction with 5% sulfuric acid, a heating extraction sequence, and injection with headspace and GC-MS in selected-ion monitoring mode, gave clean separation and accurate results. Repeatability was achieved for both wheat and corn after spiking samples at the 0.01 mg/kg level, with RSD values of 7.6 and 6.3%, respectively. The LOD and LOQ values were 0.46 and 1.38 µg/kg, respectively. The mean value of phosphine residue in wheat was 8.43 µg/kg, with an RSD of 8.17%, whereas...
J AOAC Int., 2018
Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by diffe... more Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by different Fusarium species in many types of grains and food commodities. It has high damage impact on human and animal immune systems. Objective: This in vitro study aimed to evaluate the influence of silver nanoparticles (Ag-NPs) as an inhibitor for the DON toxin excreted from some Fusarium spp., which were isolated from barely, wheat, and corn grains. Methods: Ag-NPs were estimated on Minimum Inhibitory Concentration, using levels of 5, 25, 50, 75, and 100 ppm, while the effect on DON was conducted with ELISA. Tri13 and Tri7 primers were used to evaluate the impact of Ag-NPs on the DNA of tested toxigenic Fusarium isolates. Results: Results revealed that the relative density values (Rd, %) of the isolated Fusarium from barley, wheat, and corn grains were 41.27, 26.47, and 30.76%, respectively. The predominant fungus was F. graminearum and F. culmorum in wheat and barley, respectively. The maximum inhibition diameters used for concentrations were 0.5, 2.8, 3.2, 3.3, and 3.31 mm, respectively. The impact of Ag-NPs on genomic structure was limited. Results demonstrated that Ag-NPs have the ability to reduce the linear growth of Fusarium spp. and eliminate the DON toxin to 34.44, 34.60, and 34.89% at 50, 75, and 100 ppm. Conclusions: Ag-NPs are considered nontransgenic substances, and their impact on Fusarium DNA under tested concentrations has been neglected. Ag-NPs may work as an alternative to fungicides to reduce fungal growth and eliminate DON mycotoxins.
J. AOAC Int., 2020
Medicinal herbs are the ancient, traditional way of treating many diseases and are now considered... more Medicinal herbs are the ancient, traditional way of treating many diseases and are now considered the first natural source of pharmaceutical active ingredients. Therefore, it is very important to focus on the hygiene of these plants so as to make sure they are safe for consumption. This work aimed to monitor the common heavy and radioactive elements in some commonly used herbs: anise, chamomile, clover, cumin, coriander, fennel, roselle, rosemary, sage, and thyme. A total of 12 elements were measured including 2 radionuclides, Al, As, Cd, Hg, Co, Cr, Ni, Pb, Sr, Th, U, and V. Heavy metals are ecologically and biologically important, and may be involved in some health disorder symptoms within the human body. Samples were digested with a microwave digester and measurements were completed with ICP-MS/MS in Helium mode to increase sensitivity, lower the background, and avoid interferences. Method validation and verification were performed through the spiking process at 2.0 µg/kg level, and then RSD, LOD, and LOQ were calculated. Recoveries ranged from 93-103% for all elements and RSD% from 2.8-9.6%. Hg and Th were not detected in all samples, while U was detected in some sample of anise, rosemary, sage, and thyme, and ranged from 0.018-0.048 mg/kg. As was detected in anise, fennel, roselle, and rosemary, and ranged from 0.0.031-5.88 mg/kg. Al, Cd, Co, Cr, Ni, Pb, Sr, and V were detected in most samples of all herbs, and ranged from 3.88-17.80, 0.122-0.654, 0.019-0.851, 0.344-2.91, 1.872-5.82, 0.120-12.56, 0.128-0.844, and 0.083-0.912 mg/kg, respectively.
J. AOAC Int., 2020
Wheat and barley grains are two of the most important nutritional grains for humans and animals a... more Wheat and barley grains are two of the most important nutritional grains for humans and animals and they play an essential role in the nutritional cycle by different ratios according to people's nutritional habits. This work aimed to monitor ten of the most important heavy metals in some European-origin wheat and barley grains during the season of 2018. The measured elements, Al, As, Cd, Co, Cr, Hg, Mo, Ni, Pb, and V, are of importance ecologically and biologically and may be involved in many health disorders affecting the human body. Moisture, protein, and specific grain weights were checked. Samples were digested using microwave acid digestion and the elements measured with ICP-MS/MS in He mode to increase sensitivity, lower the background, and avoid interference. Method validation and verification were carried out through spiking at two levels (2.0 and 10 ppb), then RSD, LOD, and LOQ were calculated. Recoveries were >97% for all elements at both levels with an RSD of <7.6%. Results revealed that As, Cd, Hg, and Pb were not detected in most wheat and barley samples, whereas Cd was detected in one sample of Ukrainian wheat and two samples of Estonian barley (but in very small traces). Pb was detected in three samples of Polish wheat (in very small traces). Al, Mo, and Ni were detected in some samples of wheat and barley of all origins, whereas other elements were at very low levels considered to be negligible concentrations.
Phosphine is considered the main fumigant material used for long time for controlling insect pest... more Phosphine is considered the main fumigant
material used for long time for controlling insect
pests in stored grains. This research was focused
on the determination of phosphine residues in
cereal matrixes (mainly wheat and corn) after the
fumigation process, using a new procedure
developed to reduce the number of analytical steps
and improve the chromatographic separation,
identification, and quantitation of analyte, thus
leading to enhanced total efficiency and sensitivity.
This method, using gastight vials for extraction
with 5% sulfuric acid, a heating extraction
sequence, and injection with headspace and GCMS
in selected-ion monitoring mode, gave clean
separation and accurate results. Repeatability was
achieved for both wheat and corn after spiking
samples at the 0.01 mg/kg level, with RSD values of
7.6 and 6.3%, respectively. The LOD and LOQ
values were 0.46 and 1.38 μg/kg, respectively. The
mean value of phosphine residue in wheat was
8.43 μg/kg, with an RSD of 8.17%, whereas it was
8.09 μg/kg in corn, with an RSD of 7.75%. All
residues detected in all the replicates were below
the estimated maximum residue limit for wheat and
corn (0.1 mg/kg). The highest residue value for
wheat was 9.85 μg/kg and the lowest was
7.70 μg/kg, whereas for corn, the highest value was
9.03 μg/kg and the lowest 7.30 μg/kg.
Zearalenone (ZEA) is mycotoxin contaminants of foods and feeds and produced mainly by fungi belon... more Zearalenone (ZEA) is mycotoxin contaminants of foods and feeds and produced mainly by fungi belonging to the genus Fusarium. A polyphasic approach consisting of morphological, chemical and molecular characterization was applied on 37 isolates of different species of Fusarium. Randomly representative sample of wheat grains were collected from different areas of Saudi Arabia for isolation trials. The most of Fusarium were namely; Fusarium graminearum, F. verticilliodes, F. oxysporium, F. culmorum, F. avenaceum, F. redolen, F. solani, F. udum, F. semitectum F. chlamydosporum, F. proliferatum and F. poae. Many protocols were used to determine the ability to excrete zearalenone (ZEA) as well as identify the toxigenic Fusarium isolates as bioassay, immunoassay, chromatographic and molecular procedures. The yeast of Saccharomyces cerevisiae and Kluyveromyces marxianus were tested to differentiate between toxigenic and non-toxigenic Fusarium isolates. Also, Immuno-affinity column and auto-ELISA were used to determine the ZEA and their findings largely identical with HPLC results. The presences of the toxigenic genes is correlate with toxicity therefor polymerase chain reaction (PCR) was performed using one set of primers specifically targeted to gene of ZEA biosynthesis. The toxigenic Fusarium species reacted positively with tri5-gene specific PCR primer [d (GCT GCTCATC ACTTTGC TCAG)-3]. This specific primer gave good screening for zearalenone producers as well as primitive differentiate between toxigenic and non-toxigenic Fusarium isolates but it lacks quantification estimation. Also, it failed to put all toxigenic isolates in one group and/or sub-cluster. This detection provided importance information to predict toxigenic profiles which may be present in wheat grains. The objective of the current study found the accurate, cheap and realistic estimation of ZEA toxin contamination to appropriate strategy to detoxify and/or decontaminate this toxin.
Foodborne Pathogens and Disease, Jun 1, 2014
The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing m... more The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing mycotoxins in animal feed. This study aimed to evaluate the β-D-glucan biopolymers as a mycotoxin binder for fumonisin (FUM) and deoxynivalenol (DON) toxins as well as their effect on the nutritional value of soybean, which is considered one of the important feed row materials. The evaluation was carried out using some toxigenic Fusarium isolates (Fusarium solani, F. oxysporum, and F. verticillioides) in vitro and in vivo. The FUM and DON levels were determined by immune affinity column. The F. verticillioides was the most toxigenic, followed by F. oxysporum and lastly F. solani, while secretion of DON toxin was determined to be greater than FUM with all the tested fungi. The effectiveness of β-D-glucan biopolymers on FUM and DON absorption was greater than clay and calcium propionate. In vivo, treating soybean seeds with β-D-glucan biopolymers led to reduction in the level of FUM and DON toxins in seeds artificially inoculated by F. verticillioides. β-D-glucan treatment also has a low effect on nutritional components of the seeds compared to untreated ones. In conclusion, this study found a new approach to reduce Fusarium mycotoxins in feed to an allowable safe limit and at the same time maintaining the nutritional value of these materials.
Journal of AOAC International, Sep 1, 2018
Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by diffe... more Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by different Fusarium species in many types of grains and food commodities. It has high damage impact on human and animal immune systems. Objective: This in vitro study aimed to evaluate the influence of silver nanoparticles (Ag-NPs) as an inhibitor for the DON toxin excreted from some Fusarium spp., which were isolated from barely, wheat, and corn grains. Methods: Ag-NPs were estimated on Minimum Inhibitory Concentration, using levels of 5, 25, 50, 75, and 100 ppm, while the effect on DON was conducted with ELISA. Tri13 and Tri7 primers were used to evaluate the impact of Ag-NPs on the DNA of tested toxigenic Fusarium isolates. Results: Results revealed that the relative density values (Rd, %) of the isolated Fusarium from barley, wheat, and corn grains were 41.27, 26.47, and 30.76%, respectively. The predominant fungus was F. graminearum and F. culmorum in wheat and barley, respectively. The maximum inhibition diameters used for concentrations were 0.5, 2.8, 3.2, 3.3, and 3.31 mm, respectively. The impact of Ag-NPs on genomic structure was limited. Results demonstrated that Ag-NPs have the ability to reduce the linear growth of Fusarium spp. and eliminate the DON toxin to 34.44, 34.60, and 34.89% at 50, 75, and 100 ppm. Conclusions: Ag-NPs are considered nontransgenic substances, and their impact on Fusarium DNA under tested concentrations has been neglected. Ag-NPs may work as an alternative to fungicides to reduce fungal growth and eliminate DON mycotoxins.
Journal of AOAC INTERNATIONAL, 2021
Background Cereal grains are an important for the nutrition of both humans and animals, and contr... more Background Cereal grains are an important for the nutrition of both humans and animals, and contribute to the nutrition cycle in different ways. Chemical contaminants are important to be monitored in food due to their direct effects on human health. Objective This work aimed to monitor some of the hazardous chemical contaminants i.e., organochlorines (OCs), pyrethroids, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in wheat and barley grains of European origin during 2019. Method Samples were collected consecutively during the season and the QuEChERS technique (quick, easy, cheap, effective, rugged, and safe) followed by GC-tandem mass spectrometry (GC-MS/MS) analysis was used in the extraction and cleaning up for all analyzed compounds. The method was verified, and a recovery study was performed at two spiking levels: 0.01 and 0.05 µg/g. RSD(%), LOD, and LOQ were calculated. Recovery ranged from 78.70–104.00% for all compounds at both levels at RSD 2...
Malathion in-vitro biodegradation study was conducted in liquid medium with five bacterial strain... more Malathion in-vitro biodegradation study was conducted in liquid medium with five bacterial strains labeled S1, S2, S3, S4 and S5 isolated from newly reclaimed agricultural soil. Malathion residues were measured at successive intervals until 30 days after incubation, paralleled with control samples. Malathion Recovery rate was performed at 0.1 and one mg kg -1 , achieved values were 91.30 and 98.70%, respectively, limit of detection (LOD) was 0.03 mg kg -1 while limit of quantification (LOQ) was 0.1 mg kg -1 . Malathion half-life values (RL 50 ) were 16.68, 20.27, 21.33, 12.72 and 12.49 days for S1, S2, S3, S4 and S5, respectively and control value was 27.50 days. No significant effect on malathion occurred with S2 (Bacillus amyloliquefaciens ) and S3 ( Staphylococcus sciuri ) treatments. S1 ( Pseudomonas aeruginosa ), S4 ( Bacillus pseudomycoides ) and S5 ( Bacillus licheniformis ) treatments showed significant effect that increased malathion degradation rate compared to control tre...
Journal of AOAC INTERNATIONAL, 2020
Wheat and barley grains are of the most important nutritional grains for human and animal which p... more Wheat and barley grains are of the most important nutritional grains for human and animal which play an essential role in the nutritional cycle by different ratios according to people nutritional habits. This work aimed to monitor 10 of the most important heavy metals in some European origin wheat and barley grains during the season of 2018. The measured elements Al, As, Cd, Co, Cr, Hg, Mo, Ni, Pb and V of the importance ecologically and biologically which may involve in many health disorder symptoms in human body. Moisture, protein and specific weight of grains have been checked. Samples were digested using microwave acid digestion and elements measured with ICP-MS/MS on He mode to increase sensitivity, lower the background and avoid interference. Method validation and verification were done thru spiking in two levels 2.0 and 10 ppb, then RSD, LOD and LOQ were calculated. Recoveries were >97% for all elements with both levels with RSD of < 7.6%. Results revealed that As, Cd, ...
Journal of AOAC International, Jan 3, 2018
Deoxynivalenol (DON) is one of the most important fungal mycotoxins excretedby different species ... more Deoxynivalenol (DON) is one of the most important fungal mycotoxins excretedby different species in many types of grains and food commodities. It has high damage impact on human and animal immune systems. This in vitro study aimed to evaluate the influence of silver nanoparticles (Ag-NPs) as an inhibitor for the DON toxin excreted from some spp., which were isolated from barely, wheat, and corn grains. Ag-NPs were estimated on Minimum Inhibitory Concentration, using levels of 5, 25, 50, 75, and 100 ppm, while the effect on DON was conducted with ELISA. and primers were used to evaluate the impact of Ag-NPs on the DNA of tested toxigenic Fusarium isolates. Results revealed that the relative density values (Rd, %) of the isolated from barley, wheat, and corn grains were 41.27, 26.47, and 30.76%, respectively. The predominant fungus was and in wheat and barley, respectively. The maximum inhibition diameters used for concentrations were 0.5, 2.8, 3.2, 3.3, and 3.31 mm, respectively. The...
Foodborne Pathogens and Disease, 2014
The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing m... more The walls of yeast cells, which contain β-D-glucan biopolymers, have an active role in reducing mycotoxins in animal feed. This study aimed to evaluate the β-D-glucan biopolymers as a mycotoxin binder for fumonisin (FUM) and deoxynivalenol (DON) toxins as well as their effect on the nutritional value of soybean, which is considered one of the important feed row materials. The evaluation was carried out using some toxigenic Fusarium isolates (Fusarium solani, F. oxysporum, and F. verticillioides) in vitro and in vivo. The FUM and DON levels were determined by immune affinity column. The F. verticillioides was the most toxigenic, followed by F. oxysporum and lastly F. solani, while secretion of DON toxin was determined to be greater than FUM with all the tested fungi. The effectiveness of β-D-glucan biopolymers on FUM and DON absorption was greater than clay and calcium propionate. In vivo, treating soybean seeds with β-D-glucan biopolymers led to reduction in the level of FUM and DON toxins in seeds artificially inoculated by F. verticillioides. β-D-glucan treatment also has a low effect on nutritional components of the seeds compared to untreated ones. In conclusion, this study found a new approach to reduce Fusarium mycotoxins in feed to an allowable safe limit and at the same time maintaining the nutritional value of these materials.
American Journal of Environmental Protection, 2014
Foodborne Pathogens and Disease, 2012
Date palm (Phoenix dactylifera L.) is considered the main crop in deserts and arid areas such as ... more Date palm (Phoenix dactylifera L.) is considered the main crop in deserts and arid areas such as Saudi Arabia. Five Streptomyces species and other fungal species were isolated from date palm rhizosphere soil of several cultivars, such as Barhi, Khalas, Sullaj, and Sukkari, in the Ghat and El-Gouf regions. Streptomyces strains were isolated on Biolog universal growth agar medium and were identified following Biolog methods. The predominant Streptomyces isolated from this present survey was S. plicatus followed by S. rimosus, S. rutgersensus, and S. griseus. The number of soilborne fungi in the tested soil decreased with the increased number of isolated Streptomyces. There was a significant positive correlation between the date palm cultivar and the number of isolated Streptomyces. The in vitro effects of isolated Streptomyces species on some toxigenic fungi were also studied. Enzyme-linked immunosorbent assay, immunoaffinity column chromatography, and high-performance liquid chromatography were used to study the mycotoxins. The concentration of most of the tested mycotoxins was reduced significantly with the presence of the Streptomyces isolates. Results indicate that some Streptomyces isolates established in date palm rhizosphere have the ability to reduce production of mycotoxins of some toxigenic fungi; thus they have the potential of reducing the subsequent disease occurrence. Therefore they can be applied in wider range as biocontrol agents.
Soil in the Environment, 2013
Bacterial degradation trial for diazinon residues was performed using bacterial strains labeled a... more Bacterial degradation trial for diazinon residues was performed using bacterial strains labeled as S1, S2, S3, S4 and S5 isolated from newly reclaimed agricultural soil. Diazinon residues were determined at successive intervals untill 30 days after incubation in liquid medium containing bacteria paralleled with control samples. Diazinon recovery rate was carried out at 0.1 and 1 mg kg -1 levels; values were 95.77 and 101.12%, respectively, limit of detection (LOD) was 0.01 mg kg -1 , while limit of quantification (LOQ) was 0.03 mg kg -1 . Diazinon half-life values (RL50) were 9.36, 8.57, 12.71, 7.51 and 8.20 days for S1, S2, S3, S4 and S5, respectively, while control value was 14.06 days. No significant effect on diazinon occurred with S3 (Staphylococc us sciuri) treatment, while S1 (Pseudomonas aeruginosa), S2 (Bacillus amyloliquefaciens), S4 (Bacillus pseudomycoides) and S5 (Bacillus licheniformis) treatments showed significant effect, that increased diazinon degradation rate comp...
Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat ... more Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat crop is exposed to many fungal infections during the cultivation stages, some of which have the ability to secrete numbers of toxic secondary metabolites that threaten the quality of grains, consumer health, producer economics and global trade exchange. Fifty-four random samples were collected from wheat which originated from different countries. The samples included 14 of soft wheat to study the extent of their contamination with Deoxynivalenol (DON) and T-2 toxin by auto-ELISA technology and r-biopharm Microtiter plate. All samples were contaminated with DON toxin except one sample, and the contamination average ranged between 40.7 and 1018.8 µg kg-1. The highest contamination rates were in Lithuanian and the lowest in Indian wheat. Meanwhile the highest average level of T-2 toxin contamination was in Lithuanian wheat grains with a rate of 377.4µg kg-1 and the lowest in Polish wheat wi...
Journal of AOAC International, 2021
BACKGROUND Cereal grains are substantial in the nutrition process for both humans and animals and... more BACKGROUND Cereal grains are substantial in the nutrition process for both humans and animals and contribute to the nutrition cycle in different ways. Chemical contaminants are important to be monitored in food due to their direct effects on human health. OBJECTIVE This work aimed to monitor some of the hazardous chemical contaminants i.e., Organochlorines (OCs), Pyrethroids, Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in wheat and barley grains of some common European origin during 2019. METHODS Samples were collected consecutively during the season and the QuEChERS technique followed by GC-MS/MS analysis was used in the extraction and cleaning up for all analyzed compounds. The method was verified, a recovery study was performed at two spiking levels 0.01 and 0.05 µg/g. RSD%, LOD and LOQ were calculated. Recovery ranged from 78.70-104.00% for all compounds at both levels at RSD 2.16-11.76%. Fat, moisture, protein and specific weight contents of bot...
Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat ... more Wheat is one of the global strategic crops and ranks third in terms of cereals production. Wheat crops are exposed to many fungal infections during their cultivation stages, some of which have the ability to secrete a number of toxic secondary metabolites that threaten the quality of the grains, consumer health, producer economics, and global trade exchange. Fifty-four random samples were collected from wheat which originated from different countries. The samples included 14 types of soft wheat to study the extent of their contamination with deoxynivalenol (DON) and T-2 toxin by auto-ELISA technology and r-biopharm microtiter plate. All samples were contaminated with DON toxin except one sample, and the values ranged between 40.7 and 1018.8 µg/kg−1. The highest contamination rates were in Lithuanian wheat and the lowest was in Indian wheat. Meanwhile, the highest average level of T-2 toxin contamination was in Lithuanian wheat grains with 377.4 µg/kg−1, and the lowest average was 11...
Journal of AOAC INTERNATIONAL
Medicinal Herbs is the old traditional way for many diseases treatment and now considered the fir... more Medicinal Herbs is the old traditional way for many diseases treatment and now considered the first natural source of the pharmaceutical active ingredients, so it is of the importance to focus on the hygiene of these plants as it should to be safe to consumption. This work aimed to monitor the common heavy and radioactive elements in some of the common used herbs namely Anise, Chamomile, Clover, Cumin, Coriander, Fennel, Roselle, Rosemary, Sage and Thyme. A total of 12 elements were measured including two radionuclides, Al, As, Cd, Hg, Co, Cr, Ni, Pb, Sr, Th, U and V. Heavy metal are ecologically and biologically important, which may involve in some health disorder symptoms in human body. Samples were digested with microwave digester and measurements have been done with ICP-MS/MS in Helium mode to increase sensitivity, lower the background and avoid interferences. Method validation and verification were done thru spiking process at 2.0 µg/kg level, then RSD, LOD and LOQ were calcula...
Journal of AOAC International
Phosphine is considered the main fumigant material used for long time for controlling insect pest... more Phosphine is considered the main fumigant material used for long time for controlling insect pests in stored grains. This research was focused on the determination of phosphine residues in cereal matrixes (mainly wheat and corn) after the fumigation process, using a new procedure developed to reduce the number of analytical steps and improve the chromatographic separation, identification, and quantitation of analyte, thus leading to enhanced total efficiency and sensitivity. This method, using gastight vials for extraction with 5% sulfuric acid, a heating extraction sequence, and injection with headspace and GC-MS in selected-ion monitoring mode, gave clean separation and accurate results. Repeatability was achieved for both wheat and corn after spiking samples at the 0.01 mg/kg level, with RSD values of 7.6 and 6.3%, respectively. The LOD and LOQ values were 0.46 and 1.38 µg/kg, respectively. The mean value of phosphine residue in wheat was 8.43 µg/kg, with an RSD of 8.17%, whereas...
J AOAC Int., 2018
Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by diffe... more Background: Deoxynivalenol (DON) is one of the most important fungal mycotoxins excreted by different Fusarium species in many types of grains and food commodities. It has high damage impact on human and animal immune systems. Objective: This in vitro study aimed to evaluate the influence of silver nanoparticles (Ag-NPs) as an inhibitor for the DON toxin excreted from some Fusarium spp., which were isolated from barely, wheat, and corn grains. Methods: Ag-NPs were estimated on Minimum Inhibitory Concentration, using levels of 5, 25, 50, 75, and 100 ppm, while the effect on DON was conducted with ELISA. Tri13 and Tri7 primers were used to evaluate the impact of Ag-NPs on the DNA of tested toxigenic Fusarium isolates. Results: Results revealed that the relative density values (Rd, %) of the isolated Fusarium from barley, wheat, and corn grains were 41.27, 26.47, and 30.76%, respectively. The predominant fungus was F. graminearum and F. culmorum in wheat and barley, respectively. The maximum inhibition diameters used for concentrations were 0.5, 2.8, 3.2, 3.3, and 3.31 mm, respectively. The impact of Ag-NPs on genomic structure was limited. Results demonstrated that Ag-NPs have the ability to reduce the linear growth of Fusarium spp. and eliminate the DON toxin to 34.44, 34.60, and 34.89% at 50, 75, and 100 ppm. Conclusions: Ag-NPs are considered nontransgenic substances, and their impact on Fusarium DNA under tested concentrations has been neglected. Ag-NPs may work as an alternative to fungicides to reduce fungal growth and eliminate DON mycotoxins.
J. AOAC Int., 2020
Medicinal herbs are the ancient, traditional way of treating many diseases and are now considered... more Medicinal herbs are the ancient, traditional way of treating many diseases and are now considered the first natural source of pharmaceutical active ingredients. Therefore, it is very important to focus on the hygiene of these plants so as to make sure they are safe for consumption. This work aimed to monitor the common heavy and radioactive elements in some commonly used herbs: anise, chamomile, clover, cumin, coriander, fennel, roselle, rosemary, sage, and thyme. A total of 12 elements were measured including 2 radionuclides, Al, As, Cd, Hg, Co, Cr, Ni, Pb, Sr, Th, U, and V. Heavy metals are ecologically and biologically important, and may be involved in some health disorder symptoms within the human body. Samples were digested with a microwave digester and measurements were completed with ICP-MS/MS in Helium mode to increase sensitivity, lower the background, and avoid interferences. Method validation and verification were performed through the spiking process at 2.0 µg/kg level, and then RSD, LOD, and LOQ were calculated. Recoveries ranged from 93-103% for all elements and RSD% from 2.8-9.6%. Hg and Th were not detected in all samples, while U was detected in some sample of anise, rosemary, sage, and thyme, and ranged from 0.018-0.048 mg/kg. As was detected in anise, fennel, roselle, and rosemary, and ranged from 0.0.031-5.88 mg/kg. Al, Cd, Co, Cr, Ni, Pb, Sr, and V were detected in most samples of all herbs, and ranged from 3.88-17.80, 0.122-0.654, 0.019-0.851, 0.344-2.91, 1.872-5.82, 0.120-12.56, 0.128-0.844, and 0.083-0.912 mg/kg, respectively.
J. AOAC Int., 2020
Wheat and barley grains are two of the most important nutritional grains for humans and animals a... more Wheat and barley grains are two of the most important nutritional grains for humans and animals and they play an essential role in the nutritional cycle by different ratios according to people's nutritional habits. This work aimed to monitor ten of the most important heavy metals in some European-origin wheat and barley grains during the season of 2018. The measured elements, Al, As, Cd, Co, Cr, Hg, Mo, Ni, Pb, and V, are of importance ecologically and biologically and may be involved in many health disorders affecting the human body. Moisture, protein, and specific grain weights were checked. Samples were digested using microwave acid digestion and the elements measured with ICP-MS/MS in He mode to increase sensitivity, lower the background, and avoid interference. Method validation and verification were carried out through spiking at two levels (2.0 and 10 ppb), then RSD, LOD, and LOQ were calculated. Recoveries were >97% for all elements at both levels with an RSD of <7.6%. Results revealed that As, Cd, Hg, and Pb were not detected in most wheat and barley samples, whereas Cd was detected in one sample of Ukrainian wheat and two samples of Estonian barley (but in very small traces). Pb was detected in three samples of Polish wheat (in very small traces). Al, Mo, and Ni were detected in some samples of wheat and barley of all origins, whereas other elements were at very low levels considered to be negligible concentrations.
Phosphine is considered the main fumigant material used for long time for controlling insect pest... more Phosphine is considered the main fumigant
material used for long time for controlling insect
pests in stored grains. This research was focused
on the determination of phosphine residues in
cereal matrixes (mainly wheat and corn) after the
fumigation process, using a new procedure
developed to reduce the number of analytical steps
and improve the chromatographic separation,
identification, and quantitation of analyte, thus
leading to enhanced total efficiency and sensitivity.
This method, using gastight vials for extraction
with 5% sulfuric acid, a heating extraction
sequence, and injection with headspace and GCMS
in selected-ion monitoring mode, gave clean
separation and accurate results. Repeatability was
achieved for both wheat and corn after spiking
samples at the 0.01 mg/kg level, with RSD values of
7.6 and 6.3%, respectively. The LOD and LOQ
values were 0.46 and 1.38 μg/kg, respectively. The
mean value of phosphine residue in wheat was
8.43 μg/kg, with an RSD of 8.17%, whereas it was
8.09 μg/kg in corn, with an RSD of 7.75%. All
residues detected in all the replicates were below
the estimated maximum residue limit for wheat and
corn (0.1 mg/kg). The highest residue value for
wheat was 9.85 μg/kg and the lowest was
7.70 μg/kg, whereas for corn, the highest value was
9.03 μg/kg and the lowest 7.30 μg/kg.
Zearalenone (ZEA) is mycotoxin contaminants of foods and feeds and produced mainly by fungi belon... more Zearalenone (ZEA) is mycotoxin contaminants of foods and feeds and produced mainly by fungi belonging to the genus Fusarium. A polyphasic approach consisting of morphological, chemical and molecular characterization was applied on 37 isolates of different species of Fusarium. Randomly representative sample of wheat grains were collected from different areas of Saudi Arabia for isolation trials. The most of Fusarium were namely; Fusarium graminearum, F. verticilliodes, F. oxysporium, F. culmorum, F. avenaceum, F. redolen, F. solani, F. udum, F. semitectum F. chlamydosporum, F. proliferatum and F. poae. Many protocols were used to determine the ability to excrete zearalenone (ZEA) as well as identify the toxigenic Fusarium isolates as bioassay, immunoassay, chromatographic and molecular procedures. The yeast of Saccharomyces cerevisiae and Kluyveromyces marxianus were tested to differentiate between toxigenic and non-toxigenic Fusarium isolates. Also, Immuno-affinity column and auto-ELISA were used to determine the ZEA and their findings largely identical with HPLC results. The presences of the toxigenic genes is correlate with toxicity therefor polymerase chain reaction (PCR) was performed using one set of primers specifically targeted to gene of ZEA biosynthesis. The toxigenic Fusarium species reacted positively with tri5-gene specific PCR primer [d (GCT GCTCATC ACTTTGC TCAG)-3]. This specific primer gave good screening for zearalenone producers as well as primitive differentiate between toxigenic and non-toxigenic Fusarium isolates but it lacks quantification estimation. Also, it failed to put all toxigenic isolates in one group and/or sub-cluster. This detection provided importance information to predict toxigenic profiles which may be present in wheat grains. The objective of the current study found the accurate, cheap and realistic estimation of ZEA toxin contamination to appropriate strategy to detoxify and/or decontaminate this toxin.