Khaled Abdelsayed | Al-Qassim University (original) (raw)

Papers by Khaled Abdelsayed

Dairy Science & Technology

The aim of this study was to investigate the angiotensin I-converting-enzyme ( ACE)inhibitory act... more The aim of this study was to investigate the angiotensin I-converting-enzyme ( ACE)inhibitory activity of tryptic hydrolysates of ovine beta-lactoglobulin, and of yoghurts made by using different starters. Ovine beta-lactoglobulin ( a mixture of variants A and B at a ratio of 50/50) was subjected to trypsin activity. The degree of hydrolysis of native whole beta-lactoglobulin reached 56, 72, 93 and 95% after 1, 2, 8 and 24 h, respectively. ACE-inhibitory activity of tryptic hydrolysates increased with the time of hydrolysis, yielding 85, 88 and 92% after 2, 12 and 24 h, respectively. The determination of ACE-inhibitory activity of some tryptic peptides separated by RP-HPLC and identified by mass spectroscopy showed that the more hydrophilic peptides showed the higher activity. Yoghurts obtained by fermentation of ovine milk with four different sets of starters, and their fractions soluble or not at pH 4.6 also showed an ACE-inhibitory activity. The maximum activity was obtained in t...

Milchwissenschaft, 2004

The antimicrobial activity of ovine whey proteins and of their peptic hydrolysates were measured ... more The antimicrobial activity of ovine whey proteins and of their peptic hydrolysates were measured against different pathogenic microbial strains. Contrary to intact a-lactalbumin and α-lactoglobulin, their peptic hydrolysates inhibited the growth of Escherichia coli HB101, E. coli Cip812, Bacillus subtilis Cip5265 and Staphylococcus aureus 9973. This inhibitory action was dose-dependent against all the studied bacterial strains. RP-HPLC separation of peptic peptides of β-lactoglobulin demonstrated that the simultaneous presence of hydrophilic and hydrophobic peptides was necessary to antimicrobial activity. No antimicrobial activity was detected against Salmonella enterica Cip5858, Listeria innocua R1007 or Streptococcus mutans Cip103220T.

Journal of Food Measurement and Characterization, 2017

Peel is a major waste from cactus pear juice industry accounting for about 38 % of the fruit weig... more Peel is a major waste from cactus pear juice industry accounting for about 38 % of the fruit weight. New concept of snacks preparation has been developed using instant controlled pressure drop (Détente instantanée controlee, DIC) techniques that provide a texturing stage between initial and final hot air drying stages. In this study, the application of DIC of cactus pear peel (CPP) was performed to be used as starch-free snacks with functional attributes. DIC resulted in high crispness CPP snacks with improved structural and nutritional attributes as well as high relative expansion ratio (up to 21 times). DIC expanded CPP snacks exhibited cutting force (3.34 N) that was much lower than untreated CPP (19.41 N). It is worth noting that optimized DIC treatment (P = 0.6 MPa for t = 15 s) allowed more availability of phenolic compounds and β-carotene by 83 and 551 %, respectively. In addition, antioxidant activity was increased up to 53 %. Results showed that steam pressure had significant effect on fat and alcohol insoluble solids (AIS) contents, wherein the correlation coefficients revealed critical relationships between structural and biochemical availabilities. Therefore, DIC could be used as an innovative technology to value this by-product leading to manufacture of crispy CPP snacks with high nutritious quality. There was a significant difference among the DIC treated and untreated CPP in respect to sensory properties, DIC treated CPP at operation conditions of saturated steam pressure = 0.6 MPa and processing time = 15 had the highest acceptability.

Food and Nutrition Sciences, 2019

In the present investigation, the valorization of sweet potato (Ipomoea batatas L.) wastes into f... more In the present investigation, the valorization of sweet potato (Ipomoea batatas L.) wastes into food application with health benefits was studied. Growing interest in the replacement of synthetic food antioxidants by natural ones has fostered research on vegetable sources and screening of raw materials to identify new antioxidants. Different parts of sweet potato contain various phenolic activities. The sweet potato peel had the highest antioxidant activity as compared to other parts. It was reported that sweet potato contains bioactive compounds such as Flavonoids, Polyphenols, The present study was executed to examine the antioxidant components of sweet potato peel and their addition to fermented cow's milk to improve lipid profile in rats fed high fat diet. Fermented milk was prepared from cow's milk fortified with 1% and 2% of sweet potato peels (SPP), before inoculation with starter culture containing (S. thermophilus TH4, L. acidophilus La5 and L. bulgaricus).

Journal of the Korean Society for Applied Biological Chemistry, 2014

Composition of amino acids and biogenic amines (BA) in different cheeses (Ras, Blue and Mish) wer... more Composition of amino acids and biogenic amines (BA) in different cheeses (Ras, Blue and Mish) were estimated. The amino acids content of Ras cheese after 6 and 24 months of ripening were 33.1 and 26.6 mg/g, respectively. In Blue cheese, after 6 and 12 months ripening, the levels ranged from 29.2 to 25.5 mg/g, whereas in Mish cheese the levels were 33.9 and 30.0 mg/g, respectively. The concentrations of cadaverine and tryptamine were similar in the Mish and Ras cheeses. Level of phenylethylamine accumulation was relatively similar in Ras and Blue cheeses, whereas levels of histamine and tryptamine were high in Ras cheese, reaching 260 and 200 mg/kg, respectively. The toxicological effects of specific BA on liver and kidney functions, as well as biochemical parameters in rats were assayed. The type and the concentration of BA accumulation in cheeses affected the functions of liver and kidney in rats treated with BA. Rats treated with 1 mg amines showed difference in total proteins and albumin during the experimental period except after 6 days, wherein no difference in albumin was noted. In addition, treatment with 2 mg amines showed significant decreased in total proteins and albumin during the testing period, except after 2, 4, and 6 days, wherein no changes in total proteins and albumin levels were detected. The highest concentration of amines (3 mg/ kg/daily) showed decrease in total proteins and albumin after 2, 8, and 10 days. Histological examination revealed that organs were moderately affected by direct injection of BA as compared with organs from control groups. Liver marked vascular congestion with abnormal double central vein occurances leading to fibrosis, whereas in the kidney, thickened vascular spaces were observed.

Bioscience Research, 2020

SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans. Th... more SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans. The most common symptoms at the onset of illness were fever, cough and myalgia or fatigue. Less common symptoms were sputum production; headache, hemoptysis and diarrhea patients had lymphopenia. All patients had pneumonia with abnormal findings on chest CT; Moreover Complications included acute respiratory distress syndrome, RNA anemia, acute cardiac injury. Until now there is no specific treatment available for SARS-CoV-2. In this review, we aimed to provide some information about clinical effects of Ginger to develop safe and effective therapeutic agents from Ginger derived compounds against SARS-CoV-2. Otherwise, Ginger is one of the most important medicinal agents in various alternative systems of medical scientific studies have shown that ginger use in treating colds, headache, nausea, stomach upset, and diarrhea. Moreover, scientific studies have shown that ginger has anti-inflammatory, anti-oxidative, immunomodulatory, and bronchodilator.

Annals of Agricultural Sciences, 2014

In this research, bioactive compounds found in peanut skins (PS), pomegranate peels (PP) and oliv... more In this research, bioactive compounds found in peanut skins (PS), pomegranate peels (PP) and olive pomace (OP) were extracted using ethanol (80%), ethyl acetate and n-hexane. Ethanol extract showed slightly better antioxidant characteristics compared with ethyl acetate and hexane extracts. Extracts showed varying degrees of antioxidant potential in different test systems in a dose-dependent manner, whereas, antioxidant capacity of extracts was found to be in parallel with their higher phenolic contents. Total phenolic compounds (as gallic acid equivalent) ranged between 0.89 and 16.6, 1.83 and 261, and 1.56 and 124 mg gallic acid/g extract for OP, PS and PP, respectively. Ethanol extracts of different by-products were added to ghee at concentrations of 200, 400 and 600 ppm, respectively. BHA was also added to ghee at a concentration of 200 ppm for comparison. All samples were incubated at 63°C for 21 days. Ethanol extracts of PS, OP and PP gave good antioxidant activity during accelerated oxidative incubation of ghee. The results revealed that ethanolic extracts under study, at a concentration of 200 ppm, could be used to retard fat auto-oxidation.

Journal of Food and Dairy Sciences, 2019

Purpose:The present study investigated AFM 1 contamination in raw milk, kareish cheese and yoghur... more Purpose:The present study investigated AFM 1 contamination in raw milk, kareish cheese and yoghurt and studied the abilities of heating and probiotic bacteria to reduce AFM 1 contamination in both raw milk and yoghurt. Methods: AFM 1 was detected in raw milk in 10 of 12 samples (83.3%) from each season. Two methods were used to assess the toxigenic potential. HPTLC was performed for aflatoxin detection. Aflatoxin M 1 contamination milk and selected dairy products was investigated against heating and Lactobacillus acidophilus La 5 and Bifidobacterium lactis Bb 12 and its combination. Result: Cheese had the highest mean values concentration of AFM 1 (527.4 and 651.3 ng/kg), and yoghurt had the lowest concentration (39.13 and 64.68 ng/kg) while, raw milk samples were (207.0 and 311.8 ng/kg) during summer and winter, respectively. The concentration of toxin in 83.33% of the examined cheese samples exceeded the EU limit (50 ng/kg), and 70.83% of these samples exceeded the Codex limit (500 ng/kg) during both seasons. Boiling degraded 26.71% of the AFM 1. Whereas, pasteurization only degraded 15.45%. In yoghurt, two strains of probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium lactis) each gradually reduced the AFM 1 concentration as a function of time in milk contaminated with 25 ng/l, with complete elimination by the end of the refrigerated storage period (3 days), while, the combination of both probiotic bacteria (L. acidophilus and B. lactis) was better able to reduce AFM 1 in milk contaminated with 50.0 ng/kg or 75 ng/kg AFM 1 .Conclusion: The most extensive reductions of the AFM 1 concentration were to 41.80 ng/kg (45.3%), 22.6 ng/kg (69.90%) and 7.12 ng/kg (92.8%), which were achieved using the same concentration of each strain individually and in combination, respectively, after two days in milk contaminated with 75 ng/kg. No AFM 1 was detected after three days using the combined strains.

Nahrung-food, 2003

Yoghurts are mostly produced from cow milk and to a very limited extent from ewe milk. The evolut... more Yoghurts are mostly produced from cow milk and to a very limited extent from ewe milk. The evolution of caseins and whey proteins in ovine milk submitted to different thermal treatments (63°C/30 min; 73°C/15 min; 85°C/10 min or 96°C/5 min) was followed during fermentation of yoghurts and during their storage up to 14 days, using two different sets of starters. One set of starter LAB was a “ropy” culture (YC-191( which is a well-defined mixed strain culture containing Streptococcus thermophilus ST-143 and Lactobacillus delbrueckii subsp. bulgaricus (LB-18 and LB-CH2). The other set of starter bacteria (YC-460) was a standard yoghurt culture (“non-ropy”) containing mixed strain culture of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. Contents of free amino groups in produced yoghurts increased gradually during the fermentation, up to a maximal value obtained after 4 h fermentation, then they did not change significantly during storage of yoghurt produced with YC-191 starter. In contrary, a large drop in the amount of free amino groups was observed in the first 24 h of storage in the case of yoghurt made with YC-460 indicating that microorganisms continue still to grow in low temperatures. During fermentation and storage of both yoghurt types, α-lactalbumin was hydrolyzed to a slightly bigger extent than β-lactoglobulin. During fermentation, β-casein was slightly more degraded than αS-caseins; however, the opposite was observed during storage up to 14 days. Generally, a more intense heat pretreatment led to a higher degradation of whey proteins and caseins during fermentation and storage. Differences in proteolytic activity between the two starters used (whey proteins more degraded by YC-191; caseins more degraded by YC-460) may lead to improvement in production and formulation of yoghurts differing in their physicochemical and rheological properties.

Journal of Food Safety, 2013

The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Do... more The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Domiati cheese supplemented with probiotic cultures on the growth inhibition of foodborne pathogens (Staphylococcus aureus, Escherichia coli, Listeria monocytogenes and Salmonella enteritidis) inoculated in cheese during storage at 4C for 42 days was investigated. BCSO showed antimicrobial effect on the survival of St. aureus, E. coli, L. monocytogenes and Sa. enteritidis inoculated into probiotic Domiati cheese samples. BCSO at concentration of 0.2% w/w had the most effective antimicrobial activity on pathogens when compared to the control. L. monocytogenes and Sa. enteritidis were more resistant against BCSO up to 28 days, whereas E. coli and St. aureus were more resistant up to 14 days of storage. Storage life of BCSO-supplemented chesses was extended under refrigerated conditions with low microbial loads. BCSO-supplemented Domiati chesses had also improved physicochemical and sensory properties.

Journal of Food Biochemistry, 2006

(ALA) upon removal of Ca 2+ were determined by surface hydrophobicity, calorimetry and circular d... more (ALA) upon removal of Ca 2+ were determined by surface hydrophobicity, calorimetry and circular dichroism. Native ewe's ALA resisted trypsinolysis, showing 4% maximum degradation after 20 h of hydrolysis. Removal of bound calcium by addition of either ethylenediaminetetraacetic acid or ethylene glycol bis b-aminoethyl ether-N,N,N,N-tetraacetic acid induced major protein conformational changes, enhancing its susceptibility to trypsinolysis, and leading to complete degradation of the protein. Reversed-phase high-performance liquid chromatography profiles of tryptic hydrolysate of Ca 2+ -free ALA were nearly the same through the whole enzymatic incubation period (24 h) showing the absence of sequential hydrolytic mechanism. They were characterized by the presence of five main peaks representing hydrophobic large-sized peptides. Cleaving the S-S bonds in the resulting hydrolysates with 2-mercaptoethanol gave rise to new peaks representing more hydrophilic and hydrophobic peptides.

Journal of Food Safety, 2013

The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Do... more The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Domiati cheese supplemented with probiotic cultures on the growth inhibition of foodborne pathogens (Staphylococcus aureus, Escherichia coli, Listeria monocytogenes and Salmonella enteritidis) inoculated in cheese during storage at 4C for 42 days was investigated. BCSO showed antimicrobial effect on the survival of St. aureus, E. coli, L. monocytogenes and Sa. enteritidis inoculated into probiotic Domiati cheese samples. BCSO at concentration of 0.2% w/w had the most effective antimicrobial activity on pathogens when compared to the control. L. monocytogenes and Sa. enteritidis were more resistant against BCSO up to 28 days, whereas E. coli and St. aureus were more resistant up to 14 days of storage. Storage life of BCSO-supplemented chesses was extended under refrigerated conditions with low microbial loads. BCSO-supplemented Domiati chesses had also improved physicochemical and sensory properties.

Saudi Journal of Biological Sciences, 2013

Black cumin seed oil (BCSO) was tested for its inhibitory effect against some pathogenic bacteria... more Black cumin seed oil (BCSO) was tested for its inhibitory effect against some pathogenic bacteria (Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 8739, Listeria monocytogenes Scott A and Salmonella enteritidis PT4) in Domiati cheese during cold storage. Physical, chemical and sensorial changes in cheese during storage were recorded. Pasteurized milk was inoculated before renneting with a mixed culture of bacteria at ca. 4 log CFU mL À1 . In vitro and in situ supplementation with BCSO showed antimicrobial impact on the growth of S. aureus, E. coli, L. monocytogenes and S. enteritidis inoculated into media and cheese samples. Supplementing of cheese with BCSO (0.1% or 0.2%, w/w) significantly reduced the counts of the inoculated pathogens by ca. 1.3 log and 1.5 log CFU g À1 after 21 days of storage. In addition, BCSO controlled the development of titratable acidity, limited the changes in ripening indices, flavor components and kept considerable physicochemical and sensorial properties of cheese.

The aim of this study was to investigate the angiotensin I-converting-enzyme (ACE)-inhibitory act... more The aim of this study was to investigate the angiotensin I-converting-enzyme (ACE)-inhibitory activity of tryptic hydrolysates of ovine beta\betabeta-lactoglobulin, and of yoghurts made by using different starters. Ovine beta\betabeta-lactoglobulin (a mixture of variants A and B at a ratio of 50/50) was subjected to trypsin activity. The degree of hydrolysis of native whole beta\betabeta-lactoglobulin reached 56, 72, 93 and 95% after 1, 2, 8 and 24 h, respectively. ACE-inhibitory activity of tryptic hydrolysates increased with the time of hydrolysis, yielding 85, 88 and 92% after 2, 12 and 24 h, respectively. The determination of ACE-inhibitory activity of some tryptic peptides separated by RP-HPLC and identified by mass spectroscopy showed that the more hydrophilic peptides showed the higher activity. Yoghurts obtained by fermentation of ovine milk with four different sets of starters, and their fractions soluble or not at pH 4.6 also showed an ACE-inhibitory activity. The maximum activity was obtai...

SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans The... more SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans The most common symptoms at onset of illness were fever, cough and myalgia or fatigue Less common symptoms were sputum production;headache, haemoptysis and diarrhea patients had lymphopenia All patients had pneumonia with abnormal findings on chest CT;Moreover Complications included acute respiratory distress syndrome, RNA aemia, acute cardiac injury Until now there is no specific treatment available for SARS-CoV-2 In this review, we aimed to provide some information about clinical effects of Ginger to develop safe and effective therapeutic agents from Ginger derived compounds against SARS-CoV-2 Otherwise, Ginger is one of the most important medicinal agents in various alternative systems of medical scientific studies have shown that ginger use in treating colds, headache, nausea, stomach upset, and diarrhea Moreover scientific studies have shown that ginger has anti-inflammatory, anti-oxid...

Quatre types de levains ont ete utilises pour la fabrication de yaourts a partir de laits de breb... more Quatre types de levains ont ete utilises pour la fabrication de yaourts a partir de laits de brebis ayant subi un pre-traitement thermique different. Le degre d'hydrolyse des caseines et des proteines du lactoserum dependait des ferments lactiques utilises. Au cours de la fermentation, la caseine est davantage degradee que les caseines S ; l' -lactalbumine (ALA) est davantage degradee que la -lactoglobuline (BLG). L' -lactalbumine et la -lactoglobuline ont ete obtenues pures par chromatographie sur resine echangeuse d'anions. La -lactoglobuline e��tait un melange des deux variants A et B tandis que l' -lactalbumine n'etait composee que d'une seule fraction. La -lactoglobuline existe sous une forme monomerique a pH acide et a faible force ionique mais se dimerise a pH neutre. Contrairement a son homologue bovin, la -lactoglobuline ovine est sensible a l'action de la pepsine. Des hydrolysats pepsiques des proteines du lactoserum ont montre une activite antimicrobienne contre Escherichia coli, Bacillus subtilis et Staphylococcus aureus.

Dairy Science & Technology

The aim of this study was to investigate the angiotensin I-converting-enzyme ( ACE)inhibitory act... more The aim of this study was to investigate the angiotensin I-converting-enzyme ( ACE)inhibitory activity of tryptic hydrolysates of ovine beta-lactoglobulin, and of yoghurts made by using different starters. Ovine beta-lactoglobulin ( a mixture of variants A and B at a ratio of 50/50) was subjected to trypsin activity. The degree of hydrolysis of native whole beta-lactoglobulin reached 56, 72, 93 and 95% after 1, 2, 8 and 24 h, respectively. ACE-inhibitory activity of tryptic hydrolysates increased with the time of hydrolysis, yielding 85, 88 and 92% after 2, 12 and 24 h, respectively. The determination of ACE-inhibitory activity of some tryptic peptides separated by RP-HPLC and identified by mass spectroscopy showed that the more hydrophilic peptides showed the higher activity. Yoghurts obtained by fermentation of ovine milk with four different sets of starters, and their fractions soluble or not at pH 4.6 also showed an ACE-inhibitory activity. The maximum activity was obtained in t...

Milchwissenschaft, 2004

The antimicrobial activity of ovine whey proteins and of their peptic hydrolysates were measured ... more The antimicrobial activity of ovine whey proteins and of their peptic hydrolysates were measured against different pathogenic microbial strains. Contrary to intact a-lactalbumin and α-lactoglobulin, their peptic hydrolysates inhibited the growth of Escherichia coli HB101, E. coli Cip812, Bacillus subtilis Cip5265 and Staphylococcus aureus 9973. This inhibitory action was dose-dependent against all the studied bacterial strains. RP-HPLC separation of peptic peptides of β-lactoglobulin demonstrated that the simultaneous presence of hydrophilic and hydrophobic peptides was necessary to antimicrobial activity. No antimicrobial activity was detected against Salmonella enterica Cip5858, Listeria innocua R1007 or Streptococcus mutans Cip103220T.

Journal of Food Measurement and Characterization, 2017

Peel is a major waste from cactus pear juice industry accounting for about 38 % of the fruit weig... more Peel is a major waste from cactus pear juice industry accounting for about 38 % of the fruit weight. New concept of snacks preparation has been developed using instant controlled pressure drop (Détente instantanée controlee, DIC) techniques that provide a texturing stage between initial and final hot air drying stages. In this study, the application of DIC of cactus pear peel (CPP) was performed to be used as starch-free snacks with functional attributes. DIC resulted in high crispness CPP snacks with improved structural and nutritional attributes as well as high relative expansion ratio (up to 21 times). DIC expanded CPP snacks exhibited cutting force (3.34 N) that was much lower than untreated CPP (19.41 N). It is worth noting that optimized DIC treatment (P = 0.6 MPa for t = 15 s) allowed more availability of phenolic compounds and β-carotene by 83 and 551 %, respectively. In addition, antioxidant activity was increased up to 53 %. Results showed that steam pressure had significant effect on fat and alcohol insoluble solids (AIS) contents, wherein the correlation coefficients revealed critical relationships between structural and biochemical availabilities. Therefore, DIC could be used as an innovative technology to value this by-product leading to manufacture of crispy CPP snacks with high nutritious quality. There was a significant difference among the DIC treated and untreated CPP in respect to sensory properties, DIC treated CPP at operation conditions of saturated steam pressure = 0.6 MPa and processing time = 15 had the highest acceptability.

Food and Nutrition Sciences, 2019

In the present investigation, the valorization of sweet potato (Ipomoea batatas L.) wastes into f... more In the present investigation, the valorization of sweet potato (Ipomoea batatas L.) wastes into food application with health benefits was studied. Growing interest in the replacement of synthetic food antioxidants by natural ones has fostered research on vegetable sources and screening of raw materials to identify new antioxidants. Different parts of sweet potato contain various phenolic activities. The sweet potato peel had the highest antioxidant activity as compared to other parts. It was reported that sweet potato contains bioactive compounds such as Flavonoids, Polyphenols, The present study was executed to examine the antioxidant components of sweet potato peel and their addition to fermented cow's milk to improve lipid profile in rats fed high fat diet. Fermented milk was prepared from cow's milk fortified with 1% and 2% of sweet potato peels (SPP), before inoculation with starter culture containing (S. thermophilus TH4, L. acidophilus La5 and L. bulgaricus).

Journal of the Korean Society for Applied Biological Chemistry, 2014

Composition of amino acids and biogenic amines (BA) in different cheeses (Ras, Blue and Mish) wer... more Composition of amino acids and biogenic amines (BA) in different cheeses (Ras, Blue and Mish) were estimated. The amino acids content of Ras cheese after 6 and 24 months of ripening were 33.1 and 26.6 mg/g, respectively. In Blue cheese, after 6 and 12 months ripening, the levels ranged from 29.2 to 25.5 mg/g, whereas in Mish cheese the levels were 33.9 and 30.0 mg/g, respectively. The concentrations of cadaverine and tryptamine were similar in the Mish and Ras cheeses. Level of phenylethylamine accumulation was relatively similar in Ras and Blue cheeses, whereas levels of histamine and tryptamine were high in Ras cheese, reaching 260 and 200 mg/kg, respectively. The toxicological effects of specific BA on liver and kidney functions, as well as biochemical parameters in rats were assayed. The type and the concentration of BA accumulation in cheeses affected the functions of liver and kidney in rats treated with BA. Rats treated with 1 mg amines showed difference in total proteins and albumin during the experimental period except after 6 days, wherein no difference in albumin was noted. In addition, treatment with 2 mg amines showed significant decreased in total proteins and albumin during the testing period, except after 2, 4, and 6 days, wherein no changes in total proteins and albumin levels were detected. The highest concentration of amines (3 mg/ kg/daily) showed decrease in total proteins and albumin after 2, 8, and 10 days. Histological examination revealed that organs were moderately affected by direct injection of BA as compared with organs from control groups. Liver marked vascular congestion with abnormal double central vein occurances leading to fibrosis, whereas in the kidney, thickened vascular spaces were observed.

Bioscience Research, 2020

SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans. Th... more SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans. The most common symptoms at the onset of illness were fever, cough and myalgia or fatigue. Less common symptoms were sputum production; headache, hemoptysis and diarrhea patients had lymphopenia. All patients had pneumonia with abnormal findings on chest CT; Moreover Complications included acute respiratory distress syndrome, RNA anemia, acute cardiac injury. Until now there is no specific treatment available for SARS-CoV-2. In this review, we aimed to provide some information about clinical effects of Ginger to develop safe and effective therapeutic agents from Ginger derived compounds against SARS-CoV-2. Otherwise, Ginger is one of the most important medicinal agents in various alternative systems of medical scientific studies have shown that ginger use in treating colds, headache, nausea, stomach upset, and diarrhea. Moreover, scientific studies have shown that ginger has anti-inflammatory, anti-oxidative, immunomodulatory, and bronchodilator.

Annals of Agricultural Sciences, 2014

In this research, bioactive compounds found in peanut skins (PS), pomegranate peels (PP) and oliv... more In this research, bioactive compounds found in peanut skins (PS), pomegranate peels (PP) and olive pomace (OP) were extracted using ethanol (80%), ethyl acetate and n-hexane. Ethanol extract showed slightly better antioxidant characteristics compared with ethyl acetate and hexane extracts. Extracts showed varying degrees of antioxidant potential in different test systems in a dose-dependent manner, whereas, antioxidant capacity of extracts was found to be in parallel with their higher phenolic contents. Total phenolic compounds (as gallic acid equivalent) ranged between 0.89 and 16.6, 1.83 and 261, and 1.56 and 124 mg gallic acid/g extract for OP, PS and PP, respectively. Ethanol extracts of different by-products were added to ghee at concentrations of 200, 400 and 600 ppm, respectively. BHA was also added to ghee at a concentration of 200 ppm for comparison. All samples were incubated at 63°C for 21 days. Ethanol extracts of PS, OP and PP gave good antioxidant activity during accelerated oxidative incubation of ghee. The results revealed that ethanolic extracts under study, at a concentration of 200 ppm, could be used to retard fat auto-oxidation.

Journal of Food and Dairy Sciences, 2019

Purpose:The present study investigated AFM 1 contamination in raw milk, kareish cheese and yoghur... more Purpose:The present study investigated AFM 1 contamination in raw milk, kareish cheese and yoghurt and studied the abilities of heating and probiotic bacteria to reduce AFM 1 contamination in both raw milk and yoghurt. Methods: AFM 1 was detected in raw milk in 10 of 12 samples (83.3%) from each season. Two methods were used to assess the toxigenic potential. HPTLC was performed for aflatoxin detection. Aflatoxin M 1 contamination milk and selected dairy products was investigated against heating and Lactobacillus acidophilus La 5 and Bifidobacterium lactis Bb 12 and its combination. Result: Cheese had the highest mean values concentration of AFM 1 (527.4 and 651.3 ng/kg), and yoghurt had the lowest concentration (39.13 and 64.68 ng/kg) while, raw milk samples were (207.0 and 311.8 ng/kg) during summer and winter, respectively. The concentration of toxin in 83.33% of the examined cheese samples exceeded the EU limit (50 ng/kg), and 70.83% of these samples exceeded the Codex limit (500 ng/kg) during both seasons. Boiling degraded 26.71% of the AFM 1. Whereas, pasteurization only degraded 15.45%. In yoghurt, two strains of probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium lactis) each gradually reduced the AFM 1 concentration as a function of time in milk contaminated with 25 ng/l, with complete elimination by the end of the refrigerated storage period (3 days), while, the combination of both probiotic bacteria (L. acidophilus and B. lactis) was better able to reduce AFM 1 in milk contaminated with 50.0 ng/kg or 75 ng/kg AFM 1 .Conclusion: The most extensive reductions of the AFM 1 concentration were to 41.80 ng/kg (45.3%), 22.6 ng/kg (69.90%) and 7.12 ng/kg (92.8%), which were achieved using the same concentration of each strain individually and in combination, respectively, after two days in milk contaminated with 75 ng/kg. No AFM 1 was detected after three days using the combined strains.

Nahrung-food, 2003

Yoghurts are mostly produced from cow milk and to a very limited extent from ewe milk. The evolut... more Yoghurts are mostly produced from cow milk and to a very limited extent from ewe milk. The evolution of caseins and whey proteins in ovine milk submitted to different thermal treatments (63°C/30 min; 73°C/15 min; 85°C/10 min or 96°C/5 min) was followed during fermentation of yoghurts and during their storage up to 14 days, using two different sets of starters. One set of starter LAB was a “ropy” culture (YC-191( which is a well-defined mixed strain culture containing Streptococcus thermophilus ST-143 and Lactobacillus delbrueckii subsp. bulgaricus (LB-18 and LB-CH2). The other set of starter bacteria (YC-460) was a standard yoghurt culture (“non-ropy”) containing mixed strain culture of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. Contents of free amino groups in produced yoghurts increased gradually during the fermentation, up to a maximal value obtained after 4 h fermentation, then they did not change significantly during storage of yoghurt produced with YC-191 starter. In contrary, a large drop in the amount of free amino groups was observed in the first 24 h of storage in the case of yoghurt made with YC-460 indicating that microorganisms continue still to grow in low temperatures. During fermentation and storage of both yoghurt types, α-lactalbumin was hydrolyzed to a slightly bigger extent than β-lactoglobulin. During fermentation, β-casein was slightly more degraded than αS-caseins; however, the opposite was observed during storage up to 14 days. Generally, a more intense heat pretreatment led to a higher degradation of whey proteins and caseins during fermentation and storage. Differences in proteolytic activity between the two starters used (whey proteins more degraded by YC-191; caseins more degraded by YC-460) may lead to improvement in production and formulation of yoghurts differing in their physicochemical and rheological properties.

Journal of Food Safety, 2013

The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Do... more The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Domiati cheese supplemented with probiotic cultures on the growth inhibition of foodborne pathogens (Staphylococcus aureus, Escherichia coli, Listeria monocytogenes and Salmonella enteritidis) inoculated in cheese during storage at 4C for 42 days was investigated. BCSO showed antimicrobial effect on the survival of St. aureus, E. coli, L. monocytogenes and Sa. enteritidis inoculated into probiotic Domiati cheese samples. BCSO at concentration of 0.2% w/w had the most effective antimicrobial activity on pathogens when compared to the control. L. monocytogenes and Sa. enteritidis were more resistant against BCSO up to 28 days, whereas E. coli and St. aureus were more resistant up to 14 days of storage. Storage life of BCSO-supplemented chesses was extended under refrigerated conditions with low microbial loads. BCSO-supplemented Domiati chesses had also improved physicochemical and sensory properties.

Journal of Food Biochemistry, 2006

(ALA) upon removal of Ca 2+ were determined by surface hydrophobicity, calorimetry and circular d... more (ALA) upon removal of Ca 2+ were determined by surface hydrophobicity, calorimetry and circular dichroism. Native ewe's ALA resisted trypsinolysis, showing 4% maximum degradation after 20 h of hydrolysis. Removal of bound calcium by addition of either ethylenediaminetetraacetic acid or ethylene glycol bis b-aminoethyl ether-N,N,N,N-tetraacetic acid induced major protein conformational changes, enhancing its susceptibility to trypsinolysis, and leading to complete degradation of the protein. Reversed-phase high-performance liquid chromatography profiles of tryptic hydrolysate of Ca 2+ -free ALA were nearly the same through the whole enzymatic incubation period (24 h) showing the absence of sequential hydrolytic mechanism. They were characterized by the presence of five main peaks representing hydrophobic large-sized peptides. Cleaving the S-S bonds in the resulting hydrolysates with 2-mercaptoethanol gave rise to new peaks representing more hydrophilic and hydrophobic peptides.

Journal of Food Safety, 2013

The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Do... more The impact of adding cold-pressed black cumin seed oil (BCSO) at levels of 0.1 and 0.2% w/w to Domiati cheese supplemented with probiotic cultures on the growth inhibition of foodborne pathogens (Staphylococcus aureus, Escherichia coli, Listeria monocytogenes and Salmonella enteritidis) inoculated in cheese during storage at 4C for 42 days was investigated. BCSO showed antimicrobial effect on the survival of St. aureus, E. coli, L. monocytogenes and Sa. enteritidis inoculated into probiotic Domiati cheese samples. BCSO at concentration of 0.2% w/w had the most effective antimicrobial activity on pathogens when compared to the control. L. monocytogenes and Sa. enteritidis were more resistant against BCSO up to 28 days, whereas E. coli and St. aureus were more resistant up to 14 days of storage. Storage life of BCSO-supplemented chesses was extended under refrigerated conditions with low microbial loads. BCSO-supplemented Domiati chesses had also improved physicochemical and sensory properties.

Saudi Journal of Biological Sciences, 2013

Black cumin seed oil (BCSO) was tested for its inhibitory effect against some pathogenic bacteria... more Black cumin seed oil (BCSO) was tested for its inhibitory effect against some pathogenic bacteria (Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 8739, Listeria monocytogenes Scott A and Salmonella enteritidis PT4) in Domiati cheese during cold storage. Physical, chemical and sensorial changes in cheese during storage were recorded. Pasteurized milk was inoculated before renneting with a mixed culture of bacteria at ca. 4 log CFU mL À1 . In vitro and in situ supplementation with BCSO showed antimicrobial impact on the growth of S. aureus, E. coli, L. monocytogenes and S. enteritidis inoculated into media and cheese samples. Supplementing of cheese with BCSO (0.1% or 0.2%, w/w) significantly reduced the counts of the inoculated pathogens by ca. 1.3 log and 1.5 log CFU g À1 after 21 days of storage. In addition, BCSO controlled the development of titratable acidity, limited the changes in ripening indices, flavor components and kept considerable physicochemical and sensorial properties of cheese.

The aim of this study was to investigate the angiotensin I-converting-enzyme (ACE)-inhibitory act... more The aim of this study was to investigate the angiotensin I-converting-enzyme (ACE)-inhibitory activity of tryptic hydrolysates of ovine beta\betabeta-lactoglobulin, and of yoghurts made by using different starters. Ovine beta\betabeta-lactoglobulin (a mixture of variants A and B at a ratio of 50/50) was subjected to trypsin activity. The degree of hydrolysis of native whole beta\betabeta-lactoglobulin reached 56, 72, 93 and 95% after 1, 2, 8 and 24 h, respectively. ACE-inhibitory activity of tryptic hydrolysates increased with the time of hydrolysis, yielding 85, 88 and 92% after 2, 12 and 24 h, respectively. The determination of ACE-inhibitory activity of some tryptic peptides separated by RP-HPLC and identified by mass spectroscopy showed that the more hydrophilic peptides showed the higher activity. Yoghurts obtained by fermentation of ovine milk with four different sets of starters, and their fractions soluble or not at pH 4.6 also showed an ACE-inhibitory activity. The maximum activity was obtai...

SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans The... more SARS-CoV-2 is a novel strain of coronavirus that has not been previously identified in humans The most common symptoms at onset of illness were fever, cough and myalgia or fatigue Less common symptoms were sputum production;headache, haemoptysis and diarrhea patients had lymphopenia All patients had pneumonia with abnormal findings on chest CT;Moreover Complications included acute respiratory distress syndrome, RNA aemia, acute cardiac injury Until now there is no specific treatment available for SARS-CoV-2 In this review, we aimed to provide some information about clinical effects of Ginger to develop safe and effective therapeutic agents from Ginger derived compounds against SARS-CoV-2 Otherwise, Ginger is one of the most important medicinal agents in various alternative systems of medical scientific studies have shown that ginger use in treating colds, headache, nausea, stomach upset, and diarrhea Moreover scientific studies have shown that ginger has anti-inflammatory, anti-oxid...

Quatre types de levains ont ete utilises pour la fabrication de yaourts a partir de laits de breb... more Quatre types de levains ont ete utilises pour la fabrication de yaourts a partir de laits de brebis ayant subi un pre-traitement thermique different. Le degre d'hydrolyse des caseines et des proteines du lactoserum dependait des ferments lactiques utilises. Au cours de la fermentation, la caseine est davantage degradee que les caseines S ; l' -lactalbumine (ALA) est davantage degradee que la -lactoglobuline (BLG). L' -lactalbumine et la -lactoglobuline ont ete obtenues pures par chromatographie sur resine echangeuse d'anions. La -lactoglobuline e��tait un melange des deux variants A et B tandis que l' -lactalbumine n'etait composee que d'une seule fraction. La -lactoglobuline existe sous une forme monomerique a pH acide et a faible force ionique mais se dimerise a pH neutre. Contrairement a son homologue bovin, la -lactoglobuline ovine est sensible a l'action de la pepsine. Des hydrolysats pepsiques des proteines du lactoserum ont montre une activite antimicrobienne contre Escherichia coli, Bacillus subtilis et Staphylococcus aureus.