الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Purslane (Portulaca oleracea L.) is an important plant naturally found as a weed in field crops and lawns. Purslane is widely distributed around the globe and is popular as a potherb in many areas of Europe, Asia, and the Mediterranean region. This plant possesses mucilaginous substances which are of medicinal importance. It is a rich source of potassium (494 mg/100 g) followed by magnesium (68 mg/100 g) and calcium (65 mg/100 g) and possesses the potential to be used as vegetable source of omega-3 fatty acid. It is very good source of alpha-linolenic acid (ALA) and gamma-linolenic acid (LNA, 18 : 3 w3) (4 mg/g fresh weight) of any green leafy vegetable. It contained the highest amount (22.2 mg and 130 mg per 100 g of fresh and dry weight, resp.) of alpha-tocopherol and ascorbic acid (26.6 mg and 506 mg per 100 g of fresh and dry weight, resp.). The oxalate content of purslane leaves was reported as 671–869 mg/100 g fresh weight. The antioxidant content and nutritional value of purslane are important for human consumption. It revealed tremendous nutritional potential and has indicated the potential use of this herb for the future.
For centuries, marigold (C. officinalis) has been used as a traditional treatment to treat everything from the common cold to rheumatism. The makeup of a vast number of secondary metabolites has been revealed via pharmacological actions. A valuable natural pigment, lutein that can be isolated from C. officinalis at a low cost and contains at least 80% carotenoids entailing 79 % lutein and 5 % zeaxanthin. Perhaps, Lutein-deficiency may be one of the causes of age-related vision impairment in the human body. Lutein, derived from marigolds, has been authorized by the European Union as food additives and approved by the Food and Agriculture Organization. The marigold flower which mainly consists of carotenoid-lutein and flavonoid Patuletin are highly demanded, which considerably enhances the uptake of dye to metal mordanting for industrial application studied for the nutritional supplements. Quercetagetin, another useful isolated molecule, has shown potential for the treatment of obesity and diabetes. The ethanolic extract of C. officinalis flowers determined antioxidant activity by using three different assays, including DPPH, which reduces the energy and radical scavenging activity of superoxide in different concentrations. Marigold flower extracts showed better reducing power than ascorbic acid, while the other assays recorded less than standard.
The obtained results can be summarized as follow:
1. Purslane Extract:
• The purslane extract had high total soluble solids, protein and ash content.
• Purslane extract is rich in antioxidant activity (84.49%), making it a good natural source of antioxidants.
• Purslane extract is considered also, a good source of total phenolic content.
2. Marigold Extract:
• Marigold extract was characterized by high total solids, ash and protein.
• The antioxidant activity DPPH (%) of marigold extract was 93.47%, which makes marigold extract a rich natural source of antioxidants.
• Marigold extract is also considered a good source of total phenolic and total flavonoid compounds.
3. Using Purslane Extracts in Making Stirred Probiotic Yoghurt:
• The total solids of purslane bio-yoghurt were increased with increasing of purslane concentrations. While it decrease with the progression of storage periods up to 15 days.
• Purslane bio-yoghurt fat content decreased with increasing storage period at refrigerator temperature up to 15 days; additionally, purslane bio-yoghurt fat content decreased with increasing purslane concentration.
• The acidity of purslane bio-yoghurt was found to increase with increasing purslane extract concentrations and during storage period at refrigerator temperature up to 15 days.
• The pH values of purslane bio-yoghurt were found to gradually decrease with increasing purslane extract concentration and during storage period at refrigerator temperature up to 15 days.
• Total nitrogen values of purslane bio-yoghurt decreased up to the end of storage periods at refrigerator temperature in all treatments. While the total nitrogen values of purslane bio-yoghurt were found to increase with increasing purslane extract concentrations.
• The ash content increased gradually as the concentration of purslane extract increased; the purslane bio-yoghurt sample had higher ash content than the control sample.
• As purslane concentrations increased up to 0.3%, the rates of syneresis decreased, while they increased with the addition of 0.4% purslane extract.
• The density of purslane bio-yoghurt increased with increasing purslane extract concentrations and during the storage period up to 15 days.
• Yoghurt samples containing purslane had higher antioxidant activity (DPPH %) than control sample.
• The radical scavenging activity values of T4, which contained 0.4% purslane extract, were three fold higher than those of control sample.
• The total phenolic content increased gradually as the purslane extract concentration increased.
• In purslane probiotic yoghurt samples, there was an increase in total flavonoid content with increased purslane extract.
• The total flavonoid content of treatments 4 which contain 0.4% purslane extract was about twofold higher than that of control sample.
• Total viable bacteria, Lactobacilli, Streptococci and Bifidobacteria counts were increased with increasing of purslane concentrations in all treatments.
• Total viable bacteria, Lactobacilli, Streptococci and Bifidobacteria counts of purslane bio-yoghurt were increased up to 5 days of storage and then decreased until the end of the storage period in all treatments.
• The counts of probiotic bacteria for all storage periods met the number suggested by Auty et al. (2001) that probiotic products should contain at least 107 CFU/ mL or g.
• Moulds and yeasts did not detected in fresh and after 5 days of storage, and then detected and increased gradually after 10 days of storage, with the storage progressing up to 15 days.
• The counts of moulds and yeasts decreased with increasing purslane concentrations.
• Coliform bacteria were not detected in both fresh and during storage periods in all treatments.
• The addition of purslane extract enhanced the flavour of the resultant yoghurt, and stirred yoghurt with purslane extract had higher flavour scores than the control, both when fresh and in all storage periods up to 15 days.
• The treatments that contain 0.4% purslane extract stirred purslane bio-yoghurt had higher overall scores in all storage periods at refrigerator temperature.
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4. Using purslane extracts in making ice milk:
A. Purslane ice milk mix:
• The relative viscosity, density and weight per gallon in pounds of purslane ice milk mix were increased by increasing the level of purslane extract added.
B. Purslane Ice milk:
• The density, as well as weight per gallon of resultant ice milk, decreased with the increase of purslane extract levels.
• The overrun of the resultant ice milk increased with the addition of purslane extracts.
• The highest values of melting resistant after 10 and 50 minutes were recorded in treatment 4, which contained 0.4% purslane extract.
• The TS, acidity, TN and ash content increased with increasing purslane concentrations, while total carbohydrate and fat content in most treatments decreased.
• As the concentration of purslane extract increased, the pH values of the purslane ice milk declined.
• The ash content of the control was also lower than that of the purslane ice milk.
• The values of antioxidant scavenging activity (DPPH %) in purslane ice milk increase with the addition of purslane extracted with methanol and acetone solvents, but samples that were extracted with acetone had higher values of antioxidant activity (DPPH %) than those extracted with methanol.
• The total phenolic content increased gradually as the purslane extract concentration increased.
• Total flavonoid content was increased in purslane ice milk samples which were extracted with methanol and acetone solvent.
• Incorporation of purslane extract in purslane ice milk leads to an increase in total bacterial counts proportional with an increase in purslane extract concentrations.
• The coliform group counts were not detected in all treatments of purslane ice milk.
• The results revealed that the flavor score had no significant difference (p>0.05) among all treatments; however, the score of flavor in purslane ice milk in all treatments were higher than that of control.
• The treatments that had a level of purslane extract (0.4 %) gained a highest score of flavor among the other purslane treatments.
• Body and texture increased as the amount of purslane extract increased; therefore, the purslane treatment of ice milk scored higher than the control in term of body and texture categories.
• The ice milk made with purslane had better melting qualities than the control.
• The T4 of purslane ice milk containing 0.4 % purslane extract had higher total scores, followed by the control sample.
5. Making Stirred Probiotic Yogurt with Marigold Extracts:
• The total solids content of marigold bio-yoghurt decreased with storage period up to 15 days.
• The total solids content of marigold bio-yoghurt increased as marigold extract concentrations increased.
• The fat content of marigold bio-yoghurt decreased with increasing marigold extract concentrations.
• The acidity of marigold bio-yoghurt increased with increasing marigold extract concentrations and during storage periods at refrigerator temperature up to 15 days.
• The pH values of marigold bio-yoghurt decreased with increasing marigold extract concentrations and during storage periods at refrigerator temperature up to 15 days.
• The total nitrogen values of marigold probiotic yoghurt decreased up to the end of storage periods at refrigerator temperature in all treatments.
• Ash content in the marigold bio-yoghurt samples were greater than those in the control sample as the marigold extract concentration increased.
• The syneresis decreased in the marigold bio-yogurt samples until the end of storage in all treatments.
• Throughout the storage period, the density of the marigold probiotic yoghurt increased in all treatments.
• Antioxidant activity (DPPH %) was higher in the marigold-containing yoghurt samples than in the control sample.
• T4, which included 0.4% marigold extract, had more three times the radical scavenging activity values of the control sample.
• As the concentration of marigold extract increased, the total phenolic content gradually increased.
• The samples of marigold probiotic yoghurt that contain marigold extract exhibited higher total phenolic contents (mg GAE/g) than the sample used as control.
• In marigold probiotic yoghurt samples, there was a statistically significant increase (p<0.05) in total flavonoid content with increased marigold extract.
• The Lactobacilli, Streptococci and Bifidobacteria counts were increased up to 5 days and decreased up to the end of the storage period.
• The probiotic yoghurt made with marigold had higher Bifidobacteria counts than the control sample.
• Moulds and yeasts did not found in when fresh or 5 days of storage marigold bio-yoghurts in all treatments, whereas they began to appear after 10 days and increased up to 15 days of storage.
• The flavour scores increased up to 10 days of storage before declining at 15 days for all treatments, including control.
• The body and texture of marigold stirred bio-yoghurt increased significantly (p<0.05) with an increase in marigold extract addition as well as with an increase in the storage period up to 15 days.
• The appearance score of stirred yoghurt was lower when marigold extract was present.
• The acidity score increased during storage period in control sample as well as in marigold yoghurt samples.
• The treatments 2 that contain marigold extract (0.2%) that stored for 10 days had the highest overall score, while the samples of treatment 3 when they were fresh had the lowest score.
6. Making Ice Milk with Marigold Extracts:
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A. Marigold ice milk mix:
• The relative viscosity, density and weight per gallon in poundsof marigold ice milk mix were increased by increasing of marigold extract addition.
B. Marigold Ice milk:
• The density, as well as weight per gallon of resultant ice milk, decreased with the increase of marigold extract levels.
• The overrun of the resultant ice milk increased as a result of the addition of marigold extracts.
• The highest values of melting resistance after 10 and 50 minutes were found in the control sample, followed by treatment 4, which contained 0.4% marigold extract.
• The total solids content of marigold ice milk considerably increased with increasing marigold extract concentration.
• The fat content of marigold ice milk decreased non-significantly (p>0.05) as marigold extract addition increased.
• When marigold extract content increased, marigold ice milk’s acidity increased; additionally, the marigold ice milk displayed greater acidity values than the control.
• The pH values of the marigold ice milk decreased as the marigold extract concentration increased.
• The total nitrogen values of marigold ice milk increased with increasing marigold extract concentrations.
• The total amount of carbohydrate in the marigold ice milk increased as the marigold extract concentration increased.
• With both solvents (methanol and acetone), the values of antioxidant activity (DPPH %) in marigold ice milk increased significantly (p<0.05) with the addition of marigold extract, but samples extracted with acetone had greater values of antioxidant activity (DPPH %) than samples extracted with methanol.
• As the concentration of marigold extract increased, the total phenolic content gradually increased.
• Total flavonoid content was increased in marigold ice milk samples, which were extracted with methanol and acetone solvents.
• The flavonoid values that were obtained from samples extracted with methanol were higher than those obtained with acetone extraction.
• The incorporation of marigold extract in marigold ice milk leads to an increase in total bacterial counts proportional with an increase in marigold extract concentrations.
• Yeast and mould counts, psychrotrophic bacteria and coliform bacteria counts did not detected in any samples of marigold ice milk.
• The flavour score in marigold ice milk was higher in the T1 and T2 treatments than in that of the control.
• The treatment that had a level of marigold extract (0.2%) gained the highest flavour score among other marigold treatments and control.
• Inclusion of marigold extract affected on the body and texture of marigold ice milk, body and texture increased as the amount of marigold extract increased.
• The melting properties of the marigold-infused ice milk were superior than the control.
• Adding marigold to ice milk changed the colour to yellow, lowering the score of the marigold ice milk samples, where the score of appearance and colour reduced with the addition of marigold extracts. The T2 sample of marigold ice milk containing 0.2 % marigold extract had higher scores, followed by the T1 sample.
In conclusion, this study suggests that purslane and marigold herbs can be used as natural dietary sources rich in bioactive compounds that do not cause defects when combined in different dairy products. Adding these herbs increase the nutritional value and bioactive compounds as well as enhancing the functional properties of dairy products. As a result, the use of purslane and marigold plants as a low-cost and easily accessible nutritional and functional source can be highlighted to increase the nutritional, functional, and biological value and to increase antioxidants in different dairy products.