Sami El Khatib | Lebanese International University (Lebanon) (original) (raw)

Papers by Sami El Khatib

Turkish Journal of Agriculture - Food Science and Technology

The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic ... more The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic importance in food, cosmetic and pharmaceutical industries. Meat tenderness is one of the very most important factors for customers’ acceptability. The global objective of this study was to add an additional value to Sumac by evaluating its meat tenderizing effect. Crude sumac fruits were used to create three different extracts (aqueous, ethanolic and purified enzymatic extract). Pectoralis superficialis cuts were treated with the extracts and studied for their shear stress, pH, protein and fat contents and collagen. The hypothesis that Sumac could have a meat tenderizing effect was supported by our results showing a significant decrease in shear stress and protein content with increase in collagen solubility. Moreover, an effect on decreasing meat fat was detected, where the aqueous sumac extract decreased significantly the fat percentage in meat. The active enzymes in Sumac were shown ...

International Journal of Environment, Agriculture and Biotechnology

Yeast extract (YE) is a natural product that can be easily produced and has the advantage to be e... more Yeast extract (YE) is a natural product that can be easily produced and has the advantage to be edible and to have a salty taste. It can be used as a food additive to give Umami taste, to intensify flavor and to give saltiness. YE can be produced naturally by autolysis, (a self lysis of the yeast cells) when incubated for four days at 45°C for the yeast cells to release their cytoplasmic content. YE is low in calories and fat, high in proteins, nucleotides and glutamic acid. It is used by food companies and restaurants as an aromatic ingredient in various applications such as soups, sauces, seasonings, snacks, ready meals and meats. The main objective of this study is to reduce the salt concentration and replace it by the edible YE in the salty crackers. In our experiment, salt concentration was reduced by 25%, 50%, 75% and 100% and replaced with YE. Physico-chemical properties of the product were investigated and sensory evaluation was performed by a set of 25 panelists. Triangle test and consumers' acceptance test were performed by comparing experimental sample against the control containing 100% salt. Obtained results supported the hypothesis; the taste of samples with 50% reduced salt showed no difference compared to those made using YE. The panelists gave the latter sample six points out of nine on hedonic scale. Our findings demonstrated that YE can be potentially used as a partial substitute of table salt.

Food Science and Technology

Despite the great progress in reducing malnutrition and famine eradication in many countries, our... more Despite the great progress in reducing malnutrition and famine eradication in many countries, our planet's population continues to be affected by many food-related defies, including vitamin and mineral deficiencies, obesity, and non-communicable diseases. These challenges are fuelled, in part, by cheap, convenient, and highly-processed foods. However, food threats are not restricted to these mentioned issues. One area to which the international community has given substantial attention is ensuring the safety from infection and contamination of the food we produce, trade, and eat. It would be disastrous if our substantial foods were to become unsafe for consumption. More efforts need to be provided to prevent food insecurity starting from aligning policies in agriculture, trade, health, education, and social protection to provide a safe and healthy diet for all. Unfortunately, food safety in Lebanon is a neglected issue. Many Lebanese food products are labeled as "unsafe" in the local and international markets, and the burden of food safety has widely increased. As meat is considered perishable food and is of great concern especially in small Lebanese butcher shops, and the absence of an updated law that protects the consumer from contaminated meat, it was important to look for an alternative method to render meat safer for consumption. Rhus coriaria or commonly known as "Sumac" has shown a promising potent anti-bacterial and antioxidant effects, and therefore, it would be interesting to assess the potential use of this condiment as a food preservative and to evaluate the prospective introduction of such artisanal product to secure the meat safety and reduce its contamination.

Heliyon

Background: Syrian Sumac, scientifically defined as Rhus coriaria, is a commonly used spice powde... more Background: Syrian Sumac, scientifically defined as Rhus coriaria, is a commonly used spice powder in the Middle East. Rhus coriaria has been shown to contain numerous compounds that have a substantial role in the food industry and in homeopathic therapy. From the retardation of oxidative processes to the treatment of fungal and bacterial infections and many more, these compounds are of great importance in improving human health and economy. Scope and approach: Several studies have been done to explore the benefits and potential uses of Rhus coriaria. In the following review, the relevant phytochemical and biological research available on Rhus coriaria have been explored. A comprehensive account of its healing activity is shown. Also presented are its phytochemical components which have medicinal, nutritional and industrial significance. Key findings and conclusions: Sumac has been studied for its use as an antibacterial, antioxidant, colorant, food and animal feed supplement, steel inhibitor in sea water and much more. Its antibacterial, antifungal and antioxidant properties make it a great and versatile tool to be used in the food industry, where it can be used as an efficient food preservative and natural, harmless food additive.

The Health Benefits of Foods - Current Knowledge and Further Development [Working Title]

Having high nutritional value and low cultivation costs, pumpkin fruit makes a great candidate to... more Having high nutritional value and low cultivation costs, pumpkin fruit makes a great candidate to be used by the food industry as a functional ingredient. To prolong its shelf life and widen the array of its potential uses in food products, drying and powdering have been applied, producing pumpkin flour. Several studies have been done to optimize the drying method of pumpkin in order to preserve or reduce the loss of its nutritional constituents and color changes during drying and storage. As vacuum freeze drying produces great quality pumpkin powder and best preserves the β-carotene and phenolic contents of the fruit, it is considered an expensive technique that could be inconvenient to be used in developing countries or for cost-reduction purposes. Air drying is a cheaper technique but results in less nutrient preservation than vacuum drying. This highlights the role of pretreatments in order to reduce the loss of nutrients and produce better quality pumpkin flour. Hot water blanching followed by metabisulfite pretreatment results in the best carotenoid stability and preservation of phenolic compounds in the produced powder. Incorporation of pumpkin powder in wheat bread could increase its nutritional value by increasing the levels of dietary fiber, pro-vitamin A β-carotene, calcium, iron, and zinc and by decreasing the carbohydrate and caloric contents.

International Journal of Current Microbiology and Applied Sciences

Vitamin D Deficiency [Working Title]

Vitamins and minerals are crucial for human health. Any deficiency can lead to major diseases; ho... more Vitamins and minerals are crucial for human health. Any deficiency can lead to major diseases; however, the most prevalent one is the vitamin D deficiency. Due to its high risk in the Middle East and Lebanon, besides its major effects, solutions to decrease this deficiency are taken nowadays. Vitamin D food fortification is the most popular solution taken now. Liposomes showed highest efficiency in vitamin D fortification. However, a study must be done in order to deduce the amounts needed in the targeted population. Therefore, before fortification starts, FDA regulations must be reviewed. Several foods succeeded in fortification with vitamin D and increasing its levels such as milk and cheddar cheese. Stability and flavors showed good results over fortification, while according to the odor, water sources showed more aroma depth than oil sources. The AOAC methods for vitamin D amount in fortified foods must be applied. Dietary 25(OH)D3 was 7.14-fold more effective at raising serum 25(OH)D than dietary vitamin D3.

Turkish Journal of Agriculture - Food Science and Technology

The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic ... more The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic importance in food, cosmetic and pharmaceutical industries. Meat tenderness is one of the very most important factors for customers’ acceptability. The global objective of this study was to add an additional value to Sumac by evaluating its meat tenderizing effect. Crude sumac fruits were used to create three different extracts (aqueous, ethanolic and purified enzymatic extract). Pectoralis superficialis cuts were treated with the extracts and studied for their shear stress, pH, protein and fat contents and collagen. The hypothesis that Sumac could have a meat tenderizing effect was supported by our results showing a significant decrease in shear stress and protein content with increase in collagen solubility. Moreover, an effect on decreasing meat fat was detected, where the aqueous sumac extract decreased significantly the fat percentage in meat. The active enzymes in Sumac were shown ...

Cancer and Oncology Research

The high prevalence of malnutrition in adult and pediatric cancer patients has been appreciated f... more The high prevalence of malnutrition in adult and pediatric cancer patients has been appreciated for decades and continues to be documented. Although the prognostic significance of nutritional status among patients with cancer remains controversial, it is generally accepted that the nutritional support is an important aspect of medical therapy. Children with cancer are particularly vulnerable to malnutrition, because they exhibit elevated substrate needs due to the disease and its treatment. At the same time, children have increased requirements of nutrients to attain appropriate growth and neurodevelopment. Malnutrition in children with cancer should not be accepted at any stage of the disease or tolerated as an inevitable process. The undernourished patients of ALL are more prone to infections, requiring longer duration of hospital stay. Therefore, optimum nutritional support to such patients can help to decrease the chances of infections and ultimately improve the outcome based on a systematic assessment. Nutritional assessment is the first step of nutritional support which will not improve the child's sense of well-being but also maintain normal growth, promote wound healing, improve tumor response to therapy and enable the child to better withstand the effects of therapy. Assessment will also help prevent over nutrition which may in some instances be detrimental to the treatment of cancer. Therefore, nutritional adequate strategies should be considered and integrated as a fundamental feature of pediatric oncology with the same diligence as one does for other supportive care measures to prevent chronic illness and adverse late effects caused by malnutrition in children with ALL.

Cancer Biology & Therapy, 2006

An ideal bladder tumor model consists in an orthotopic solitary tumor with a welldefined localiza... more An ideal bladder tumor model consists in an orthotopic solitary tumor with a welldefined localization and stage, as well as unaltered normal mucosa. None of the existing models covers all these requirements. We have created a new model, suitable for diagnostic and therapeutic purposes. Female Fisher rats were divided into different groups according to bladder preconditioning and tumor cell (AY27) administration. Generalized desepithelialization was obtained by an intravesical instillation of HCl, neutralized by NaOH. Localized desepithelialization of the bladder fundus was the result of application of a micro-swab, imbibed with the same chemicals. Tumor cells administration was either generalized (intravesical instillation) or focal (micro swab). No bladder perforations were observed. Generalized desquamation always produced multifocal tumors, whereas focal application of HCl/NaOH resulted in solitary tumors of the bladder fundus, irrespective of the method of tumor cell administration. Only hyperplasia could be detected at day 3. AY27 cells were covered by umbrella cells at day 5 and subepithelial AY 27 tumor nests, covered by full thickness epithelium were observed day 7.

Journal of Urology, 2005

We evaluated the possibility of performing endoscopic fiber-optic confocal microscopy in a rat bl... more We evaluated the possibility of performing endoscopic fiber-optic confocal microscopy in a rat bladder model and we distinguished different cell types. Rhodamine 123 (Molecular Probes, Eugene, Oregon) (100 microM) was instilled for 30 minutes in 5 tumor bearing rat bladders (AY27). Five normal rats served as controls. A Cell-viziotrade mark confocal microscopy fiber was placed transurethrally in contact with normal or transformed bladder wall. Frozen sections were obtained from the same spots and subjected to conventional fluorescence microscopy and anatomical-pathological analysis. The different cells types present in rat epithelium (umbrella, intermediate and basal cells) could easily be identified with the Cell-viziotrade mark device due to their differences in morphology and fluorescence intensity. Individual AY-27 cells could not be demarcated due to the strong fluorescence signal but the entire tumor appeared as a brightly homogenous fluorescent blot surrounded by small inflammatory cells. We report the feasibility of endoscopic, in vivo, fiber-optic confocal microscopy in the rat bladder. We distinguished tumors from normal epithelium and visualized the different epithelial cell types in nontransformed rat bladder epithelium.

Journal of Urology, 2004

Purpose: To optimize photodynamic therapy (PDT) we investigated the kinetics and biodistribution ... more Purpose: To optimize photodynamic therapy (PDT) we investigated the kinetics and biodistribution of hexylester 5-aminolevulinate (hALA) induced protoporphyrin IX (PpIX) and the therapeutic efficacy of PDT at different drug and light doses in an orthotopic rat bladder tumor model. Materials and Methods: Healthy and tumor bearing rats were instilled intravesically with hALA (4, 8 and 16 mM) for 1 hour. Fluorescence was recorded spectroscopically in situ. PpIX fluorescence distribution and quantification across the bladders was visualized with fluorescence microscopy. PDT efficacy at different fluences (15 to 80 J/cm 2 ) was histologically assessed 48 hours and 1 week after treatment.

Turkish Journal of Agriculture - Food Science and Technology

The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic ... more The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic importance in food, cosmetic and pharmaceutical industries. Meat tenderness is one of the very most important factors for customers’ acceptability. The global objective of this study was to add an additional value to Sumac by evaluating its meat tenderizing effect. Crude sumac fruits were used to create three different extracts (aqueous, ethanolic and purified enzymatic extract). Pectoralis superficialis cuts were treated with the extracts and studied for their shear stress, pH, protein and fat contents and collagen. The hypothesis that Sumac could have a meat tenderizing effect was supported by our results showing a significant decrease in shear stress and protein content with increase in collagen solubility. Moreover, an effect on decreasing meat fat was detected, where the aqueous sumac extract decreased significantly the fat percentage in meat. The active enzymes in Sumac were shown ...

International Journal of Environment, Agriculture and Biotechnology

Yeast extract (YE) is a natural product that can be easily produced and has the advantage to be e... more Yeast extract (YE) is a natural product that can be easily produced and has the advantage to be edible and to have a salty taste. It can be used as a food additive to give Umami taste, to intensify flavor and to give saltiness. YE can be produced naturally by autolysis, (a self lysis of the yeast cells) when incubated for four days at 45°C for the yeast cells to release their cytoplasmic content. YE is low in calories and fat, high in proteins, nucleotides and glutamic acid. It is used by food companies and restaurants as an aromatic ingredient in various applications such as soups, sauces, seasonings, snacks, ready meals and meats. The main objective of this study is to reduce the salt concentration and replace it by the edible YE in the salty crackers. In our experiment, salt concentration was reduced by 25%, 50%, 75% and 100% and replaced with YE. Physico-chemical properties of the product were investigated and sensory evaluation was performed by a set of 25 panelists. Triangle test and consumers' acceptance test were performed by comparing experimental sample against the control containing 100% salt. Obtained results supported the hypothesis; the taste of samples with 50% reduced salt showed no difference compared to those made using YE. The panelists gave the latter sample six points out of nine on hedonic scale. Our findings demonstrated that YE can be potentially used as a partial substitute of table salt.

Food Science and Technology

Despite the great progress in reducing malnutrition and famine eradication in many countries, our... more Despite the great progress in reducing malnutrition and famine eradication in many countries, our planet's population continues to be affected by many food-related defies, including vitamin and mineral deficiencies, obesity, and non-communicable diseases. These challenges are fuelled, in part, by cheap, convenient, and highly-processed foods. However, food threats are not restricted to these mentioned issues. One area to which the international community has given substantial attention is ensuring the safety from infection and contamination of the food we produce, trade, and eat. It would be disastrous if our substantial foods were to become unsafe for consumption. More efforts need to be provided to prevent food insecurity starting from aligning policies in agriculture, trade, health, education, and social protection to provide a safe and healthy diet for all. Unfortunately, food safety in Lebanon is a neglected issue. Many Lebanese food products are labeled as "unsafe" in the local and international markets, and the burden of food safety has widely increased. As meat is considered perishable food and is of great concern especially in small Lebanese butcher shops, and the absence of an updated law that protects the consumer from contaminated meat, it was important to look for an alternative method to render meat safer for consumption. Rhus coriaria or commonly known as "Sumac" has shown a promising potent anti-bacterial and antioxidant effects, and therefore, it would be interesting to assess the potential use of this condiment as a food preservative and to evaluate the prospective introduction of such artisanal product to secure the meat safety and reduce its contamination.

Heliyon

Background: Syrian Sumac, scientifically defined as Rhus coriaria, is a commonly used spice powde... more Background: Syrian Sumac, scientifically defined as Rhus coriaria, is a commonly used spice powder in the Middle East. Rhus coriaria has been shown to contain numerous compounds that have a substantial role in the food industry and in homeopathic therapy. From the retardation of oxidative processes to the treatment of fungal and bacterial infections and many more, these compounds are of great importance in improving human health and economy. Scope and approach: Several studies have been done to explore the benefits and potential uses of Rhus coriaria. In the following review, the relevant phytochemical and biological research available on Rhus coriaria have been explored. A comprehensive account of its healing activity is shown. Also presented are its phytochemical components which have medicinal, nutritional and industrial significance. Key findings and conclusions: Sumac has been studied for its use as an antibacterial, antioxidant, colorant, food and animal feed supplement, steel inhibitor in sea water and much more. Its antibacterial, antifungal and antioxidant properties make it a great and versatile tool to be used in the food industry, where it can be used as an efficient food preservative and natural, harmless food additive.

The Health Benefits of Foods - Current Knowledge and Further Development [Working Title]

Having high nutritional value and low cultivation costs, pumpkin fruit makes a great candidate to... more Having high nutritional value and low cultivation costs, pumpkin fruit makes a great candidate to be used by the food industry as a functional ingredient. To prolong its shelf life and widen the array of its potential uses in food products, drying and powdering have been applied, producing pumpkin flour. Several studies have been done to optimize the drying method of pumpkin in order to preserve or reduce the loss of its nutritional constituents and color changes during drying and storage. As vacuum freeze drying produces great quality pumpkin powder and best preserves the β-carotene and phenolic contents of the fruit, it is considered an expensive technique that could be inconvenient to be used in developing countries or for cost-reduction purposes. Air drying is a cheaper technique but results in less nutrient preservation than vacuum drying. This highlights the role of pretreatments in order to reduce the loss of nutrients and produce better quality pumpkin flour. Hot water blanching followed by metabisulfite pretreatment results in the best carotenoid stability and preservation of phenolic compounds in the produced powder. Incorporation of pumpkin powder in wheat bread could increase its nutritional value by increasing the levels of dietary fiber, pro-vitamin A β-carotene, calcium, iron, and zinc and by decreasing the carbohydrate and caloric contents.

International Journal of Current Microbiology and Applied Sciences

Vitamin D Deficiency [Working Title]

Vitamins and minerals are crucial for human health. Any deficiency can lead to major diseases; ho... more Vitamins and minerals are crucial for human health. Any deficiency can lead to major diseases; however, the most prevalent one is the vitamin D deficiency. Due to its high risk in the Middle East and Lebanon, besides its major effects, solutions to decrease this deficiency are taken nowadays. Vitamin D food fortification is the most popular solution taken now. Liposomes showed highest efficiency in vitamin D fortification. However, a study must be done in order to deduce the amounts needed in the targeted population. Therefore, before fortification starts, FDA regulations must be reviewed. Several foods succeeded in fortification with vitamin D and increasing its levels such as milk and cheddar cheese. Stability and flavors showed good results over fortification, while according to the odor, water sources showed more aroma depth than oil sources. The AOAC methods for vitamin D amount in fortified foods must be applied. Dietary 25(OH)D3 was 7.14-fold more effective at raising serum 25(OH)D than dietary vitamin D3.

Turkish Journal of Agriculture - Food Science and Technology

The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic ... more The Syrian Sumac (Rhus coriaria) is a widely used spice in the Arab world of attractive economic importance in food, cosmetic and pharmaceutical industries. Meat tenderness is one of the very most important factors for customers’ acceptability. The global objective of this study was to add an additional value to Sumac by evaluating its meat tenderizing effect. Crude sumac fruits were used to create three different extracts (aqueous, ethanolic and purified enzymatic extract). Pectoralis superficialis cuts were treated with the extracts and studied for their shear stress, pH, protein and fat contents and collagen. The hypothesis that Sumac could have a meat tenderizing effect was supported by our results showing a significant decrease in shear stress and protein content with increase in collagen solubility. Moreover, an effect on decreasing meat fat was detected, where the aqueous sumac extract decreased significantly the fat percentage in meat. The active enzymes in Sumac were shown ...

Cancer and Oncology Research

The high prevalence of malnutrition in adult and pediatric cancer patients has been appreciated f... more The high prevalence of malnutrition in adult and pediatric cancer patients has been appreciated for decades and continues to be documented. Although the prognostic significance of nutritional status among patients with cancer remains controversial, it is generally accepted that the nutritional support is an important aspect of medical therapy. Children with cancer are particularly vulnerable to malnutrition, because they exhibit elevated substrate needs due to the disease and its treatment. At the same time, children have increased requirements of nutrients to attain appropriate growth and neurodevelopment. Malnutrition in children with cancer should not be accepted at any stage of the disease or tolerated as an inevitable process. The undernourished patients of ALL are more prone to infections, requiring longer duration of hospital stay. Therefore, optimum nutritional support to such patients can help to decrease the chances of infections and ultimately improve the outcome based on a systematic assessment. Nutritional assessment is the first step of nutritional support which will not improve the child's sense of well-being but also maintain normal growth, promote wound healing, improve tumor response to therapy and enable the child to better withstand the effects of therapy. Assessment will also help prevent over nutrition which may in some instances be detrimental to the treatment of cancer. Therefore, nutritional adequate strategies should be considered and integrated as a fundamental feature of pediatric oncology with the same diligence as one does for other supportive care measures to prevent chronic illness and adverse late effects caused by malnutrition in children with ALL.

Cancer Biology & Therapy, 2006

An ideal bladder tumor model consists in an orthotopic solitary tumor with a welldefined localiza... more An ideal bladder tumor model consists in an orthotopic solitary tumor with a welldefined localization and stage, as well as unaltered normal mucosa. None of the existing models covers all these requirements. We have created a new model, suitable for diagnostic and therapeutic purposes. Female Fisher rats were divided into different groups according to bladder preconditioning and tumor cell (AY27) administration. Generalized desepithelialization was obtained by an intravesical instillation of HCl, neutralized by NaOH. Localized desepithelialization of the bladder fundus was the result of application of a micro-swab, imbibed with the same chemicals. Tumor cells administration was either generalized (intravesical instillation) or focal (micro swab). No bladder perforations were observed. Generalized desquamation always produced multifocal tumors, whereas focal application of HCl/NaOH resulted in solitary tumors of the bladder fundus, irrespective of the method of tumor cell administration. Only hyperplasia could be detected at day 3. AY27 cells were covered by umbrella cells at day 5 and subepithelial AY 27 tumor nests, covered by full thickness epithelium were observed day 7.

Journal of Urology, 2005

We evaluated the possibility of performing endoscopic fiber-optic confocal microscopy in a rat bl... more We evaluated the possibility of performing endoscopic fiber-optic confocal microscopy in a rat bladder model and we distinguished different cell types. Rhodamine 123 (Molecular Probes, Eugene, Oregon) (100 microM) was instilled for 30 minutes in 5 tumor bearing rat bladders (AY27). Five normal rats served as controls. A Cell-viziotrade mark confocal microscopy fiber was placed transurethrally in contact with normal or transformed bladder wall. Frozen sections were obtained from the same spots and subjected to conventional fluorescence microscopy and anatomical-pathological analysis. The different cells types present in rat epithelium (umbrella, intermediate and basal cells) could easily be identified with the Cell-viziotrade mark device due to their differences in morphology and fluorescence intensity. Individual AY-27 cells could not be demarcated due to the strong fluorescence signal but the entire tumor appeared as a brightly homogenous fluorescent blot surrounded by small inflammatory cells. We report the feasibility of endoscopic, in vivo, fiber-optic confocal microscopy in the rat bladder. We distinguished tumors from normal epithelium and visualized the different epithelial cell types in nontransformed rat bladder epithelium.

Journal of Urology, 2004

Purpose: To optimize photodynamic therapy (PDT) we investigated the kinetics and biodistribution ... more Purpose: To optimize photodynamic therapy (PDT) we investigated the kinetics and biodistribution of hexylester 5-aminolevulinate (hALA) induced protoporphyrin IX (PpIX) and the therapeutic efficacy of PDT at different drug and light doses in an orthotopic rat bladder tumor model. Materials and Methods: Healthy and tumor bearing rats were instilled intravesically with hALA (4, 8 and 16 mM) for 1 hour. Fluorescence was recorded spectroscopically in situ. PpIX fluorescence distribution and quantification across the bladders was visualized with fluorescence microscopy. PDT efficacy at different fluences (15 to 80 J/cm 2 ) was histologically assessed 48 hours and 1 week after treatment.