Effect of incorporating food-grade lactic acid in minced beef on storage stability and sensory evaluation of the produced patties

The objective of this research is to evaluate quality properties and storage stability of beef patties formulated from fresh beef incorporated with food-grade lactic acid (LA). Fresh beef was purchased from the local market immediately after slaughter, minced and formulated using water incorporated with food-grade lactic acid in concentrations of 0.0% (control); 0.5%; 0.75% and 1.00%. The LA-incorporated formulations were used in the preparation of the patties. The prepared patties were stored at a refrigeration temperature of 5 ºC for 12 days. pH, instrumental color, texture profile analysis (TPA), water activity and total viable count (TVC) were investigated. At the end of the storage period, the patties were cooked and sensory evaluated. The results revealed a significant (p ≤ 0.05) decrease in pH of the control patties from 6.2 ± 0.1 to 5.1 ± 0.2–5.4 ± 0.2 from day 8 to day 12 of the storage time. The same trend was observed in the LA-incorporated patties. The LA-incorporated patties did not show any significant differences (p ≥ 0.05) in the water activity values through all storage time. At the end of the storage time, the control had the TVC value of almost near the spoilage limit, while all LA-incorporated patties had significantly (p ≤ 0.05) lower TVC compared with the control. The results revealed high stability in the physicochemical properties as well as total microbial growth during the storage period. The hardness of the LA-incorporated patties was significantly (p ≤ 0.05) lower than that of the control sample. There was no significant (p ≥ 0.05) difference in overall sensory acceptability of the patties made from beef incorporated with food-grade lactic acid compared to the control. This study suggests that incorporating fresh beef with food-grade lactic acid in the mentioned concentrations could result in great benefits of increasing the storage life of fresh beef products with no effect on sensory quality attributes.The objective of this research is to evaluate quality properties and storage stability of beef patties formulated from fresh beef incorporated with food-grade lactic acid (LA). Fresh beef was purchased from the local market immediately after slaughter, minced and formulated using water incorporated with food-grade lactic acid in concentrations of 0.0% (control); 0.5%; 0.75% and 1.00%. The LA-incorporated formulations were used in the preparation of the patties. The prepared patties were stored at a refrigeration temperature of 5 ºC for 12 days. pH, instrumental color, texture profile analysis (TPA), water activity and total viable count (TVC) were investigated. At the end of the storage period, the patties were cooked and sensory evaluated. The results revealed a significant (p ≤ 0.05) decrease in pH of the control patties from 6.2 ± 0.1 to 5.1 ± 0.2–5.4 ± 0.2 from day 8 to day 12 of the storage time. The same trend was observed in the LA-incorporated patties. The LA-incorporated patties did not show any significant differences (p ≥ 0.05) in the water activity values through all storage time. At the end of the storage time, the control had the TVC value of almost near the spoilage limit, while all LA-incorporated patties had significantly (p ≤ 0.05) lower TVC compared with the control. The results revealed high stability in the physicochemical properties as well as total microbial growth during the storage period. The hardness of the LA-incorporated patties was significantly (p ≤ 0.05) lower than that of the control sample. There was no significant (p ≥ 0.05) difference in overall sensory acceptability of the patties made from beef incorporated with food-grade lactic acid compared to the control. This study suggests that incorporating fresh beef with food-grade lactic acid in the mentioned concentrations could result in great benefits of increasing the storage life of fresh beef products with no effect on sensory quality attributes

FOOD–DRUG INTERACTION AND THEIR CLINICAL IMPLICATIONS: SELECTED INVESTIGATIONS

Food-drug interactions occur as a result of pharmacokinetic or pharmacodynamics mechanisms. Pharmacokinetic mechanisms include what the body does to a drug while Pharmacodynamics mechanisms involve what drugs do to the body. Many types of food have been shown to influence metabolism and the absorption of drugs. Large numbers of drugs are produced and introduced yearly. The interaction between Food and drug may cause negative effects in the nutritional status of the patient as well as safety and efficacy of drug therapy. Due to the possibility of unexpected or poor outcomes, generally, food-drug interactions, in this case, should be avoided. As the good clinical practice, drugs taken by mouth must be absorbed either through the lining of the stomach or the small intestine. Reduction in the absorbance of a drug might be influenced by the presence of food in the digestive tract. The avoidance of such interactions could be possible if the drug is taken 1 hour before or 2 h after eating the food. The effects of several types of food such as milk or milk products, grapefruit and grapefruit juice, bananas, oranges, legumes, fermented meats and pickled fish and some nutrient elements such as calcium, potassium, magnesium, iron, zinc, and vitamin K are highlighted in this paper including their clinical implications

Shelf Life and Quality Attributes Of Fresh Beef Infused With Organic Acids.

Fresh beef is a highly perishable food. It has a shelf life of one day at ambient temperature and a few days at refrigerated temperature. This study was conducted with the objective of extending the shelf life of fresh beef by infusing organic acids such as citric, tartaric, acetic and lactic acids, and combination of the organic acids with sodium chloride. Fresh beef (longissmus do@ purchased from the local market were sliced and were infused with citric, acetic, lactic and tartaric acids in concentration of 0.5%, 0.75% and 1 %, and combination of 1.00% of citric and acetic acids with and without sodium chloride by placing samples in vacuum desiccators and pulling the vacuum to 29.5 in. Hg. for 20 min.,. All samples were packed in vacuum packs (22 (L) x 18 (w) crn. and stored at S°C for 28 days. pH, A, Total Plate Count (TPC), Thiobarbaturic acid values, Hunter colour values , instrumental texture, proximate composition were determined. The pH values of treated samples dropped from the initial pH of 5.30 (untreated) to 4. 20 - 4. 47 and upon storage, the pH values of all sampies increased gradually. The TPC values were lower than 10' CFUlg on day 16, 20 and 28 in samples treated with 0.5%, 0.75% and 1.00% acids, respectively. The proximate com p s iti on of treated samples was affected by infusion process. The instrumental texture of fresh beef was harder upon treatment. The maximum shelf life of treated beef was 12 - 24 days for samples treated with 0.5% of all acids, 16 - 24 days for samples treated with 0.75% and 20 - 28 for samples treated with 1.00%. Citric acid in concentration of 1.00% gave the best effect which was followed by acetic acid. In citric and acetic acids and citric and acetic acids with sodium chloride combinations, the later in the ratio of 2:1 was more effective in decreasing the initial pH of fresh beef immediately after infusion. Increasing concentration of NaCl in the infusion solution resulted in the smaller decrease in the pH values. The TPC value was observed in samples treated with 2:1 citric: acetic acids. The growth of S.aureus and E.coli 0157:H7 were significantly (B0.05) decreased by 0.85 loglo and 0.73 logto, respectively. The initial thiobarbituric acid value in untreated fresh beef was 0.735 mg MDNkg which significantly (pc 0.05) decreased in all treated samples. At the end of storage study, lowest TBA values were obtained in samples treated with 2:l citric and acetic. The increase in the addition of NaCl caused a parallel increased in TBA values. For colour, Hunter 'b' and 'L' values increased with storage time while 'a' decreased significantly (R0.05). The processed beef burger during chilled storage had a storage life of 8 days

An in vitro evaluation of films prepared from gelatin – Carica papaya methanolic extract for wound healing

This paper is a part of research aiming at preparing biodegradable films containing gelatin and Carica papaya extract for wound healing purposes in rats. Carica papaya leaves were collected and extracted using methanol aqueous method (20% methanol: 80% water). Eleven films (F1–F11) of Carica papaya extract (0–500) and gelatin (1000 mg) were prepared and investigated for selected in vitro parameters which include pH, thickness, folding endurance, water absorption capacity, tensile strength and extract released studies. Increasing concentrations of the added Carica papaya extract dropped the pH value from 7.3 ± 0.1 to 5.2 ± 0.1. Blank gelatin film had the highest value of the thickness (22.8 ± 0.9 µm). Folding endurance increased significantly (p<0.05) in both blank and composite films. In blank films the values of the folding endurance increased from 122.7 ± 3.5 – 187.6 ± 3.5 while in composite ones the values increased from 232.0 ± 8.8 to 258.3±2.5. Tensile strength value increased with increasing the addition of Carica papaya extract significantly (p<0.05) from 100.4 ± 3.4 N/cm2 to 191.5 ± 3.6 N/cm2. In contrast, within the composite films the highest addition of Carica papaya decreased the tensile strength value significantly (p<0.05) from 332.8 ± 2.2 to 84.10 ± 6.1 N/cm2. Significant differences (p<0.05) were noticed in the values of extract release. The maximum percentage of extract release was 96.6% which was scored in formulation 7 of the films (F7) while the minimum percentage of the extract release was 69.8% which was recorded in formulation 9 of the films (F9).  In conclusion, the films contained high concentrations of Carica papaya extract gave promising in vitro results and are recommended to be used for wound healing applications

INVESTIGATION ON THE CUTTING PARTICLES TRANSPORT IN HORIZONTAL WELL DRILLING

Arguably the most important prerequisite function to permit further progress in well drilling operations up to reach production is a complete removal of drilled cuttings from the well bore. This target becomes more challenging in highly-deviated to horizontal wells, where the cuttings particles have more tendency to accumulate in the lower side of the well bore and form a bed of standstill cuttings. In this study, a mathematical model based on the mechanistic theory and the three-layer approach was developed to simulate the cutting particles transport in annular flow during the horizontal drilling process. Two mathematical models were developed to investigate the cuttings transportation performance in horizontal wells. Due to high non- linearity, both were solved numerically after conversion to computer algorithms using MATLAB. The master model examined the performance of irregular shaped cuttings transported in concentric annulus by non-Newtonian fluids. The model predicted the velocities of the layers, the layer’s concentration, the dispersive shear stress, and the pressure drop. The transport performance was adequately simulated under various operational and design conditions, namely the effect of the cuttings size, cuttings shape, annular size, rate of penetration and the mud rheology in term of fluid viscosity. The second model represented a modified model which used to test the sensitivity of the frictional forces calculations, where empirical correlations were employed to replace Szilas formula to calculate the layers and wall friction stresses. The cuttings size, mud viscosity and annular size demonstrated significant effect on transport process. While the operational rate of penetration performed the lowest effect between the entire parameters of the cuttings transport. The results compared favorably with those obtained by previous investigators. Accordingly, the simulations demonstrated that the basic model could be used to analyze the cuttings transport. Thereby, it could potentially be used as design and/or analysis tools for the follow-up of transport processes in horizontal wells

An in vitro evaluation of films prepared from gelatin – Carica papaya methanolic extract for wound healing

This paper is a part of research aiming at preparing biodegradable films containing gelatin and Carica papaya extract for wound healing purposes in rats. Carica papaya leaves were collected and extracted using methanol aqueous method (20% methanol: 80% water). Eleven films (F1–F11) of Carica papaya extract (0–500) and gelatin (1000 mg) were prepared and investigated for selected in vitro parameters which include pH, thickness, folding endurance, water absorption capacity, tensile strength and extract released studies. Increasing concentrations of the added Carica papaya extract dropped the pH value from 7.3 ± 0.1 to 5.2 ± 0.1. Blank gelatin film had the highest value of the thickness (22.8 ± 0.9 µm). Folding endurance increased significantly (p<0.05) in both blank and composite films. In blank films the values of the folding endurance increased from 122.7 ± 3.5 – 187.6 ± 3.5 while in composite ones the values increased from 232.0 ± 8.8 to 258.3±2.5. Tensile strength value increased with increasing the addition of Carica papaya extract significantly (p<0.05) from 100.4 ± 3.4 N/cm2 to 191.5 ± 3.6 N/cm2. In contrast, within the composite films the highest addition of Carica papaya decreased the tensile strength value significantly (p<0.05) from 332.8 ± 2.2 to 84.10 ± 6.1 N/cm2. Significant differences (p<0.05) were noticed in the values of extract release. The maximum percentage of extract release was 96.6% which was scored in formulation 7 of the films (F7) while the minimum percentage of the extract release was 69.8% which was recorded in formulation 9 of the films (F9).  In conclusion, the films contained high concentrations of Carica papaya extract gave promising in vitro results and are recommended to be used for wound healing applications

COMPARATIVE STUDY OF LEVELS OF SELECTIVE OXIDATIVE STRESS MARKERS (MALONDIALDEHYDE, ZINC, AND ANTIOXIDANT VITAMINS A, E, AND C) IN ISCHEMIC AND NON-ISCHEMIC HEART DISEASE PATIENTS SUFFERING FROM TYPE- 2 DIABETES

Objective: The objective of the current study is to compare the levels of oxidative stress markers malondialdehyde (MDA), zinc, and antioxidant Vitamins (A, E, and C) in ischemic heart disease (IHD) and non-IHD patients with diabetes mellitus.Method: This is cross-sectional study group, conducted in the advanced diagnostic center (Khartoum- Sudan) from the period May 2013 to August 2015. Comprised 100 healthy subjects were, control group with mean (fasting blood sugar) 5.61=m mol/L, the age ranged from 22 to 78 years old, the average of the age was 50.1 years. 300 patients (78 IHD and 222 without) as cases groups, the ages ranged from 30 to 80 years. The age average was 51.2 years, all samples were in a state of fasting for 12 h, and the data were collected using a structured questionnaire and direct interview to collect information. Blood specimens were collected from both groups, and plasma levels of MDA, zinc, and antioxidant Vitamins (A, E, and C) were determined.Results: There was a significant difference between the level of serum Vitamin A, E, and MDA in diabetic patients with IHD and those diabetic without IHD (p<0.05). No significant differences in serum Vitamin C level between both groups (p>0.05).Conclusion: Due to the significant differences in serum Vitamin A, E, Zinc, and MDA between diabetics with IHD and diabetics without IHD, these parameters can be used as prognostic markers for prediction of oxidative stress and antioxidant stress of diabetic patients with IHD complications

Participation of African immigrants in the labour force of South Africa: Insights from the 2001 population census

Magister Philosophiae - MPhilThe study examines the participation of African immigrants in the South African labour force with the central question revolving around whether the immigrants create jobs through the establishment of their own businesses or take jobs from the locals. Analytical frame work used in this study includes descriptive statistics, chi-square test for association and standardized residuals, two-way analysis of variance and logistic regression. Demographic, locational and socio-economic characteristics were studied using descriptive and inferential statistical analysis. Two-factor analysis of variance was used to examine the differences on average in the African immigrants; participation in the labour force, while logistic regression was used to investigate the effect of some demographic characteristics on employment and work status.South Afric

The implementation of interior-point method for solving nonlinear constrained optimization problems

In this research, we discuss linear and nonlinear programming problems and methods. We have implemented the simplex and interior-point methods for linear programming problems. We also implement interior-point method for nonlinear programming problems. The convergence analysis and complexity of these methods are presented. Computational results that compare between the simplex method and the interior-point method are reported

Development of a multifaceted (MECSUS) protocol in the search for novel bioactive entities from microorganisms / Rasha Saad Abd Elgadir Soliman

The advent of new chemical genetic tools and high-throughput screening technologies and platforms have already led and will continue to lead in accessing the natural product diversity of microorganisms. This thesis represents a continuation of the work on the investigation into means of making better use of the advantages of new technologies and the OSMAC approach (One Strain Many Compounds) in drug discovery that the Atta-ur-Rahman Research Institute of Natural Product Discovery (RiND) at MARA University of Technology has engaged in. The result of this thesis is the MECSUS (Microtiter plate, Elicitors, Combination, Solid phase extraction, UHPLC, Statistical analysis) protocol. It involves miniaturized parallel fermentations in 96-well microtiter plate with up to ninety six different media, parallel extraction of the supernatant layer of the fungus via a polymer based solid phase extraction (SPE) plate, chromatographic assessment of the results via UHPLC, and multivariate analysis of the chromatogram s. The aforementioned protocol introduces elements of incremental novelty in the natural product screening program by means of combining and harnessing existing ideas, techniques, and technologies into a protocol for the implementation of the OSMAC approach at micro-scale. Its main advantage is the decrease of the scale of operation with the use of the 96-well microtiter plates. It’s benefits includ the possibility of overcoming few issues such as processing time and human resources that have somewhat hampered the implementation of the OSMAC approach and/or the systematic study of a large library of microorganisms. As a proof of concept for the MECSUS protocol, further evaluation on the metabolic potential of the already known fungus, Aspergillus sp. HAB10R12, was carried out through systematic alteration of the composition of the cultivation media by adding minerals and epigenetics elicitors. Computational analysis of the resulting 384 UHPLC chromatograms showed that the secondary metabolite production of Aspergillus HAB10R12 was altered by the use of sub-inhibitory concentrations of epigenetic elicitors. Various doses of the epigenetic modifiers suberoylanilide hydroxamic acid (SAHA), valproic acid, sodium butyrate, and SAHA + S-adenosylhomocysteine stimulated Aspergillus HAB10R12 secondary metabolite production.Chemical characterization of Aspergillus HAB10R12 extract, UV and Mass values, confirmed the identity of the series of peptides and pyrones previously identified, and revealed that the fungus extract is rich in compounds that potentially exceed the ones listed above. Cytotoxicity tests revealed the crude extract as well as the purified metabolites of Aspergillus HAB10R12 are potent cytotoxic compounds