Publications by authors named "Sherif M Abed"

6 Publications

  • Page 1 of 1

Effects of ultrasonic, microwave, and combined ultrasonic-microwave pretreatments on the enzymatic hydrolysis process and protein hydrolysate properties obtained from Chinese sturgeon (Acipenser sinensis).

J Food Biochem 2020 08 19;44(8):e13292. Epub 2020 Jun 19.

State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi, China.

Degree of hydrolysis (DH), yield, amino acid profile, protein solubility, and antioxidant activity of Chinese sturgeon protein hydrolysates, as influenced by thermal pretreatment, ultrasonic (US), microwave (MW), and combined US-microwave pretreatments were investigated. Initially, the samples were subjected to thermal pretreatments in order to measure their effect on DH, which increased at 55°C. The DH recorded 7.63, 5.55, and 6.02% for US, MW, and combined US-MW pretreatment (US + MW), respectively, at the optimal time (8 min). The enzymatic hydrolysis (EN) of pretreated samples increased the DH to 19.41, 14.18, and 16.91% for US + EN, MW + EN, and US + MW + EN, respectively. The US + EN treatment was most effective for obtaining higher DH and yield, which were 19.41% and 18.62%, respectively. The use of US + EN also resulted in an increase in the percentage of molecular weights (≤1,000 Da), amino acid content and protein solubility, which reached 89.24, 80.08, and 98.58%, respectively. While, US + MW + EN pretreatment has achieved the highest antioxidant activities by IC of 1,1-diphenyl-2-picrylhydrazyl and 2,2-Azinobis (3-ehtylbenzothiazoli- 6-sulfnic acid), which were 3.01 and 1.85 mg/ml, respectively, in addition to the reducing power assay, which was 0.528 at a protein concentration of 5 mg/ml. Therefore, US and combined US-MW techniques can play a promising role in the production of protein hydrolysates and the improvement of their antioxidant properties. PRACTICAL APPLICATIONS: Nowadays, interest in Chinese sturgeon production has increased as a promising source of protein and antioxidant peptides. The optimal thermal pretreatment can be used to enhance the degree of hydrolysis. The results indicated that the use of ultrasound as a pretreatment enhanced the degree of hydrolysis, which could be useful in the preparation of protein hydrolysate with higher yields. The use of combined US-MW significantly improved the antioxidant properties of the protein hydrolysate. The combined US-MW technique is a novel method for obtaining valuable peptides and protein hydrolysates that can be applied as antioxidant constituents in the food products.
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http://dx.doi.org/10.1111/jfbc.13292DOI Listing
August 2020

Proximate composition, nutritional evaluation and functional properties of a promising food: Arabian wax Cissus ( Forssk) leaves.

J Food Sci Technol 2019 Nov 31;56(11):4844-4854. Epub 2019 Jul 31.

1State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, 214122 China.

is a wild plant, extensively used during scarcity and famine; however, the information about its chemical and nutritional properties still limited. In this work, was evaluated for its chemical, nutritional and functional properties. The results revealed that mainly contained carbohydrates (72.54%), proteins (12.16%), ash (12.53%), dietary fiber (14.10%), in addition to adequate amounts of essential amino acids and minerals. Fructose, glucose, galactose, and arabinose were the major monosaccharides with a percentage of 23.32, 13.60, 1.24, and 0.25 g/100 g DW, respectively. Furthermore, it was found that contained important vitamins, including thiamin (5.37 mg/100 g DW), riboflavin (1.19 mg/100 g DW), pyridoxine (0.46 mg/100 g DW) and folic acid (0.20 mg/100 g DW). The findings of functional properties revealed good water and oil absorption capacities of 2.74 and 1.63 g/g, respectively. Foaming capacity and water solubility index were 14 and 18.74%, respectively. From these results, it can be stated that has high nutritional values, which could be used widely in food applications.
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http://dx.doi.org/10.1007/s13197-019-03947-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6828857PMC
November 2019

Spray-dried novel structured lipids enriched with medium-and long-chain triacylglycerols encapsulated with different wall materials: Characterization and stability.

Food Res Int 2019 02 24;116:538-547. Epub 2018 Aug 24.

State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University,1800 Lihu Road, Wuxi 214122, Jiangsu, PR China. Electronic address:

Novel structured lipids (SLs) enriched with medium-and long-chain triacylglycerols (MLCTs) were synthesized to combine the benefits of both arachidonic acid and medium-chain fatty acids; however, they are susceptible to oxidative degradation. In this work, the influences of the partial replacement of whey protein isolate (WPI) as the primary wall material by prebiotic carbohydrates, such as maltodextrin (MD) and inulin (IN) as the secondary wall materials on the physicochemical characteristics and oxidative stability of the spray-dried MLCTs-rich SLs microcapsules were investigated. The highest values of viscosity and zeta-potential were achieved by the WPI/IN (1:1) emulsions. Size distributions of all the emulsions were mono modal and became bimodal after microencapsulation process. The microcapsules prepared with WPI/IN (1:1) had the lowest lightness and the highest yellowness values. The partial replacement treatments increased the solubility and reduced the moisture content of the produced microcapsules. The partial replacement of WPI by IN significantly enhanced the encapsulation efficiency (89.10 ± 1.03%), wettability properties (205 ± 10.61 S), and decreased the incidence of surface oil on the microcapsules. The free oil content was noted as 5.73 ± 0.05, 3.83 ± 0.01, and 2.40 ± 0.03% for the microcapsules produced using WPI, WPI/MD (1:1), and WPI/IN (1:1), respectively. Larger microcapsules and fairer flowing properties were achieved in the powders produced with only WPI. The partial replacement of WPI by IN provided the best oxidative stability of the microencapsulated MLCTs-rich SLs. The results revealed that MD and IN with WPI together, particularly IN proved to be a good substitute secondary wall material for spray-dried MLCTs-rich SLs, therefore suggesting its usefulness in functional food applications.
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http://dx.doi.org/10.1016/j.foodres.2018.08.071DOI Listing
February 2019

Natural phospholipids: Occurrence, biosynthesis, separation, identification, and beneficial health aspects.

Crit Rev Food Sci Nutr 2019 17;59(2):253-275. Epub 2017 Oct 17.

a State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, School of Food Science and Technology , Jiangnan University , 1800 Lihu Road, Wuxi , Jiangsu , PR China.

During the last years, phospholipids (PLs) have attracted great attention because of their crucial roles in providing nutritional values, technological and medical applications. There are considerable proofs that PLs have unique nutritional benefits on human health, such as reducing cholesterol absorption, improving liver functions, and decreasing the risk of cardiovascular diseases. PLs are the main structural lipid components of cell and organelle membranes in all living organisms, and therefore, they occur in all organisms and the derived food products. PLs are distinguished by the presence of a hydrophilic head and a hydrophobic tail, consequently they possess amphiphilic features. Due to their unique characteristics, the extraction, separation, and identification of PLs are critical issues to be concerned. This review is focused on the content of PLs classes in several sources (including milk, vegetable oils, egg yolk, and mitochondria). As well, it highlights PLs biosynthesis, and the methodologies applied for PLs extraction and separation, such as solvent extraction and solid-phase extraction. In addition, the determination and quantification of PLs classes by using thin layer chromatography, high-performance liquid chromatography coupled with different detectors, and nuclear magnetic resonance spectroscopy techniques.
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http://dx.doi.org/10.1080/10408398.2017.1363714DOI Listing
July 2019

Synthesis of 1,3-dioleoyl-2-arachidonoylglycerol-rich structured lipids by lipase-catalyzed acidolysis of microbial oil from Mortierella alpina.

Bioresour Technol 2017 Nov 19;243:448-456. Epub 2017 Jun 19.

State Key Laboratory of Food Science and Technology, National Engineering Research Center for Functional Food, National Engineering Laboratory for Cereal Fermentation Technology, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, PR China.

Microbial oils (MOs) have gained widespread attention due to their functional lipids and health promoting properties. In this study, 1,3-dioleoyl-2-arachidonoylglycerol-rich structured lipids (SLs) were produced from MO and oleic acid (OA) via solvent-free acidolysis catalyzed by Lipozyme RM IM. Under the optimal conditions, the content of unsaturated fatty acids (UFAs) increased from 60.63 to 84.00%, while the saturated fatty acids (SFAs) content decreased from 39.37 to 16.00% at sn-1,3 positions in SLs. Compared with MO, arachidonic acid (ARA) content at the sn-2 position of SLs accounted for 49.71%, whereas OA was predominantly located at sn-1,3 positions (47.05%). Meanwhile, the most abundant triacylglycerol (TAG) species in SLs were (18:1-20:4-18:1), (20:4-20:4-18:1), (18:1-18:2-18:1), (18:1-18:2-18:0) and (24:0-20:4-18:1) with a relative content of 18.79%, 11.94%, 6.07%, 5.75% and 4.84%, respectively. Such novel SLs with improved functional properties enriched with UFAs are highly desirable and have the potential to be used in infant formula.
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http://dx.doi.org/10.1016/j.biortech.2017.06.090DOI Listing
November 2017

Identification of phospholipids classes and molecular species in different types of egg yolk by using UPLC-Q-TOF-MS.

Food Chem 2017 Apr 12;221:58-66. Epub 2016 Oct 12.

State Key Laboratory of Food Science and Technology, Synergetic Innovation Center of Food Safety and Nutrition, Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, PR China.

Egg phospholipids (PLs) are currently the products of greatest commercial interest with major area of importance in various fields. Therefore, in this study, duck, hen and quail egg yolk PLs were isolated by solvent extraction with chilled acetone precipitation, and subsequently separated and identified by using ultra-performance liquid chromatography with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS). Egg PLs were separated on hydrophilic interaction liquid chromatography (HILIC) with ethylene bridged hybrid (BEH) column by gradient elution using acetonitrile/ammonium formate as a mobile phase, and detected by mass spectrometry (MS) under electrospray ionization in positive and negative ion mode. Structural characterizations of 57 molecular species of egg yolk PLs were identified based on MS/MS fragment ion information and elemental composition in MassLynx 4.1 software. The obtained results showed that phosphatidylcholine (16:0-18:1), phosphatidylethanolamine (18:0-20:4), phosphatidylinositol (18:0-18:2), phosphatidylserine (18:0-18:2), sphingomyelin (d18:1/16:0) and lysophosphatidylcholine (16:0) were the predominant species among the different classes of egg yolk phospholipids.
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http://dx.doi.org/10.1016/j.foodchem.2016.10.043DOI Listing
April 2017
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