الفهرس 
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Abstract
This investigation was carried out on six types of edible wild plant leaves, namely: Chicory, Sonchus, Mallow, Sorrel, plantain and Black nightshade, which were obtained from the village of El-Zawia in Assiut, as well as, the farm of the Faculty of Agriculture at Assiut University, during the season of 2019-2020.
The present study investigated the gross chemical composition, minerals content, fatty acids, sugars content, and vitamins content of the studied plant leaves.
Also, determined of carotenoids, chlorophylls as well as phenolic compounds and flavonoids, nitrate and oxalate content and antioxidant activity were evaluated.
In addition, determined of total count of bacteria, fungi and yeasts of these plant leaves, was estimated with the study of the antimicrobial activity of the studied plant leaves extracts. Also, used the study plant leaves in the preparation of some food products (Tamia-snacks-biscuits) with studying sensory evaluation and chemical composition this products.
In addition, used of the studied plant leaves extracts that showed antifungal activity (mallow - sonchus - black nightshade) in the preparation of balady bread to study the possibility of delaying spoilage of fungal.
The results could summarized in the following points:
1- The moisture content of the studied plant leaves ranged from 75.49% for mallow leaves to 89.79% for sonchus leaves.
2- Crude protein content 18.37, 14.06, 28.99, 19.60, 19.75 and 29.67%, on dry weight for plantain, chicory, mallow, sorrel, sonchus and black nightshade leaves; respectively.
3- Sonchus leaves recorded the highest content of crude fat (4.48%) while, sorrel leaves recorded the lowest content (2.11%) on dry weight. While the other studied plant leaves contained average values of crude fat, which were 2.26% for plantain leaves, 3.91% for chicory leaves, 3.01% for mallow leaves, and 3.21% for black nightshade leaves.
4- The percentage of crude fiber ranged from 6.99% in black nightshade leaves to 11.39% in plantain leaves, while chicory leaves recorded 11.06%, mallow 8.00%, sorrel 9.02%, and sonchus11.38% on dry weight.
5- Potassium was the predominant minerals present in the study plant leaves, followed by sodium.
6- The iron was the predominant minerals among the trace elements present in the studied plant leaves, as its percentage ranged from 9.19 mg/100 g (dry weight) in sorrel to 75.87 mg/100 g in mallow leaves, followed by selenium and zinc.
7- The studied plant leaves were characterized a higher content of vitamin B12 (cobalamin), recorded which from 0.908 mg/100 gm, (dry weight) for sorrel leaves to 0.101 mg/100 gm for mallow leaves.
8- The studied plant leaves were characterized a higher level of vitamin A and K, with excepted sonchus leaves, which recorded the lowest content of vitamin A compared the studied plant leaves. While mallow leaves recorded the highest content of vitamin D and E compared the studied plant leaves.
9- No significant differences in the chlorophyll A content of the studied plant leaves, which ranged from 2.56 mg/100 g (dry weight) in chicory to 2.99 mg/100 g in plantain leaves. Also, mallow and black nightshade leaves recorded the highest contents of chlorophyll B, as it was 6.11 mg/100g (dry weight) in mallow leaves and 6.03 mg/100g in black nightshade leaves.
10- Mallow leaves were characterized a higher level of total carotenoids as well as, beta-carotene compared the studied plant leaves.
11- The black nightshade leaves was characterized by the highest content of total phenolic (12.96 mg/g dry weight), followed by sorrel leaves (12.54 mg/g dry weight), while the plantain and black nightshade leaves were characterized highest content of total flavonoids (11.62 and 11.21 mg/g dry weight; respectively) compared the studied plant leaves.
12- The result showed that, antioxidant activity of the studied plant leaves were 94.80, 83.45, 90.98, 93.37, 93.36 and 92.95% for plantain, chicory, mallow, sorrel, sonchus and black nightshade; respectively.
13- By used HPLC device, were isolated and quantified 17 phenolic compounds. The sorrel leaves recorded the highest content of pyrogallol, which was 292.59 mg/100 g dry weight compared the studied plant leaves.
14- Using HPLC device, it were isolated and quantify 14 flavonoid compounds. Also, the results showed that, Apigenin-7-glucose is the predominant of flavonoid compounds in sonchus leaves while, the second flavonoid compound is represented in mallow leaves while, kampferol 3-2 p-coumaryl-glucose was the predominant flavonoids of mallow leaves.
15- Using HPLC device, were isolated and determined 18 sugars different. Fructose, glucose, arabinose, sucrose, lactose, stachyose and galacturonic sugars were the predominate sugars, while sorbitol recorded the lowest content of sugar fractions in all the plant leaves used in the study.
16- The plantain leaves were characterized by high content of ribose and stachyose, where their ratios were 1224.55 and 1065.09 mg/100 gm dry weight; respectively. While sorrel leaves was characterized by a high content of sucrose, (2355.14 mg / 100 g dry weight) compared to the studied plant leaves.
17- The saturated fatty acids ranged from 14.18 to 31.96% of the total fatty acids while, the unsaturated fatty acids ranged from 69.03 to 85.82% of the total fatty acids in the studied plant leaves.
18- The results showed that, the highest content of nitrate was found in the mallow leaves (0.67%), followed by chicory leaves (0.35%), and sonchus leaves (0.25%) while, the highest level of oxalate was found in black nightshade leaves (0.13%), followed by sonchus leaves (0.11%), and mallow leaves (0.10%).
19- Regarding to, studying antimicrobial activity, the results showed that, the aqueous extract of mallow leaves had effect on the growth and activity of the fungal Penicillium expansum, Rhizopus oryzae and Staphylococcus aureus bacteria while, the aqueous extract of mallow leaves showed activity against Penicillium expansum and Rhizopus oryza, as the aqueous extract showed chicory leaves showed activity against Psedomonas aeruginosa, while the aqueous extract of black nightshade leaves showed activity against Candida albicans. While, plantain and sorrel leaves extracts did not activity against any of the microbial strains tested in this study.
20- from a technological point of view, the replacement of fresh coriander leaves used in preparation of Tamia dough (control) with chicory or sorrel leaves was rate 12 or 15% of composition dough prepared for Tamia, as this led to increase content of protein, crude fiber and ash in the final product of Tamia and this percentage it increases with increase replacement rate. On the other hand, the sensory evaluation showed that, no significant differences of taste, color, flavor, texture, and overall acceptability compared to Tamia prepared using 12% fresh coriander or 12% of the studied samples, while the sensory evaluation of Tamia prepared using 15% of chicory leaves or fresh sorrel leaves was better of Tamia prepared using 15% of fresh coriander plant (control).
21- The results showed that, the addition of plantain or sorrel leaves powder at rate 3 or 5% led to a significant increase in the proportion of protein and crude fat in the snacks compared with control. While, the addition of plantain or sorrel leaves powder by 5% only increase percentage of crude fiber and ash in snacks product compared to the control, in addition to, the addition of plantain or sorrel leaves powder by 3 or 5% did not have any effect on moisture in snacks compared to control. Also, the results showed that, the addition of plantain or sorrel leaves powder at rate of 3 or 5% had no significant effect on taste and flavor of the final product of snacks compared to control.
22- Also, the addition mallow or sonchus leaves powder (at rate of 3 or 5%) or black nightshade leaves powder (at rate of 1 or 3%) to the biscuit product led a significant increase in the content of crude protein, except for use black nightshade leaves powder at rate 1%, as it had no effect of protein content compared to the control. Also, the addition of mallow, sonchus and black nightshade resulted a slight but non-significant increase in content of crude fiber and ash in prepared biscuits compared to the control.
23- The sensory evaluation of biscuits prepared by addition mallow, sonchus and black nightshade leaves powder showed that, no significant effect on the taste of biscuits. As for color, the addition of mallow leaves powder led to a significant decrease in the color of biscuits compared to control.
24- The used aqueous extracts (at rate 5%) of mallow or sonchus or black nightshade leaves powder in preparation of balady bread delayed the appearance of fungal growth until seventh day compared to control, on which fungal growth appeared on the fourth day, which means an increase in the validity period for balady bread and reduce losses from it.
Recommendations:
Through the obtained data from this study, the following can be recommended:
1- The studied wild edible plants contain high levels of protein, mineral elements, crude fiber, vitamins and antioxidants.
2- It is possible to take advantage of availability of these plants at no cost or at low prices in human nutrition compared to similar cultivated leafy vegetables.
3- Such plants can be successfully used in the preparing of some food products such as Tamia and snacks.
4- Given anti-fungal activity shown by the aqueous extract of some of these plants, it can be used to delay the spoilage of balady bread, increase its validity period and reduce its waste.