الفهرس 
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Abstract
Portulacaceae comprises 25–30 genera and between 450–500 species.
Portulaca is the largest genus in the family, Portulaca oleracea: it is common name purslane in (USA and Australia), rigla (Egypt). It is an annual succulent herb in the family Portulacaceae. It’s a wide spread weed, being the eighth most common plants in the world , and can be found in Europe, Africa, United States, China and India, and also in Australia, In Egypt distributed in:
Nile phytogeographical region, Oases, Mediterranean, Sinai
The broad spectrum of the traditional uses of portulaca oleracea makes it interesting to study this plant.
This study includes:
Genetic profiling of the plant.
Chemical study of Portulaca oleracea plant including; a preliminary phytochemical screening, study of the lipoid content (saponifiable and unsaponifiable matters), quantitative and qualitative determination of phenolic and flavonoid compounds, HPLC/MS-MS study of Portulaca oleracea compounds, investigation of the plant fractions (polar and non-polar).
Nutritional value study of Portulaca oleracea plant including: water content, protein, carbohydrate, fat, minerals and vitamins content.
Biological study of Portulaca oleracea plant including; pharmacological study (anti-inflammatory, antioxidant, antihyperglycemic, analgesic and hepatoprotective activities), cytotoxic and antimicrobial activities.
Genetic study of Portulaca oleracea by DNA fingerprinting
The RAPD electrophoretic profile of the DNA sample of Portulaca oleracea amplified with the ten random primers showed distinguishable bands generating 20 fragments pattern.
Part I: Phytochemical study of Portulaca oleracea plant.
1.1 Preliminary phytochemical screening of Portulaca oleracea plant.
The results of phytochemical screening showed the presence of carbohydrates and glycosides, sterols and triterpenes, flavonoids and phenolic acids, traces of volatile components, alkaloids and nitrogenous bases, tannins, absence of crystalline sublimates, cardiac glycosides, free and combined anthraquinones, saponins, and oxidase enzymes in Portulaca oleracea.
2. Study of the lipoid content of Portulaca oleracea plant.
The lipoidal matter of Portulaca oleracea was extracted with n-hexane and subjected to saponification procedure. The unsaponifiable fractions as well as the fatty acid methyl esters were analyzed by GLC/MS.
2.1. GC/MS analysis of the unsaponifiable matter:
The GC/MS analysis of the unsaponifiable matter of the Portulaca oleracea plant revealed that Stigmasterol and Cholesterol represent the identified sterols in the sample under investigation and there are about 1.2% of the total identified components and the percentage of hydrocarbons are higher than sterols. .
2.2. GC/MS analysis of fatty acid methyl esters (FAME):
The saturated fatty acid (SFA) constituted (0.72%) while unsaturated fatty acids were the major components represented 91.97%, where 11-Octadecenoic acid, methyl ester was the major constituent represents 43.90%, the highest relative percentage of the identified unsaturated fatty acids.
The presence of the unsaturated fatty acids give a great importance and may explain the use of the plant as anti-inflammatory and antioxidant.
3. Quantitative determination of phenolic and flavonoid compounds of the Portulaca oleracea plant
HPLC analysis of phenolic compounds in Portulaca oleracea enabled the identification and quantification of 31 phenolic compounds (11 flavonoids and 20 phenolic acids).
The percentage of total identified flavonoids was 3.614%. Hesperidin was the major identified flavonoid with concentration 151.055 ppm of the total methanolic extract. The percentage of total identified phenolic acids was 13.061%. Protocatechuic was the major identified phenolic acid with concentration 470.24 ppm of the total methanolic extract of Portulaca oleracea plant.
4. Qualitative e determination of secondary metabolites of Portulaca oleracea plant using HPLC/DAD-ESI/MS analysis.
In this study a comprehensive qualitative analysis of the active constituents present in the methanolic extract of Portulaca oleracea plant were achieved by HPLC/DAD-ESI/MS and a total of About 10 phenolic compounds, (7 flavonoids, (1) isoflavonon, (1) phenolic acid,(1) phenolic acid derivative),and (1) fatty acid, (1) sterol and (4) alkaloides have been identified by both the negative and positive ionization mode based on mass measurements of the pseudomelocular [M-H] ions, pseudomelocular [M+H] ions, pseudomelocular [M+H2O] ions, pseudomelocular [M+Na] ions, pseudomelocular [M-NH3] ions, fragment ions and retention time of the compounds detected as well as comparison with reported data and by searching phytochemical dictionary of natural products database (CRC).
5. Isolation and identification of the major constituents of Portulaca oleracea plant.
5.1. Isolation and identification of the major constituents of the unsaponifiable fraction (non-polar fraction) of Portulaca oleracea plant
An aliquot of the unsaponifiable matter was subjected to fractionation on silica gel column Elution was performed starting with n-hexane and the polarity gradually increased with chloroform 5% till 100% then the polarity gradually increased with EtOAc in 5% stepwise increments till 100%. Fractions (15 ml, each) were collected, give nine main fractions; Fraction no (3) was have the main 2 spots (5-95% chloroform in n-hexane). Fraction no (3) was further purified by rechromatography on a silica gel column (50g). Gradient elution was started with n-hexane followed by n-hexane containing increasing amount of ethyl acetate by 2%. Subfractions (5 ml, each) were collected.
Sub-fraction I: showed one major spot and upon evaporation of the solvent and recrystallization from chloroform yielded compound C1 as white needle crystal, identification of (C1) is: lupeol
Sub-fraction II: showed one major spot, the residue obtained upon evaporation of the eluent was further purified by rechromatography on silica gel column gradient elution was carried out using n-hexane with increasing amounts of ethyl acetate (1% increments). Fractions of 5 ml were collected Subfractions (20-28) after pooling and evaporation yielded compound C2 as white needle crystals, identification of (C2) is: β-sitosterol.
5.2. Isolation and identification of the major constituents of the polar fraction of Portulaca oleracea plant.
The polar fraction of Portulaca oleracea (4 gm.) was chromatographed over (250 gm.) polyamide column (150 x 5 cm), gradient elution was carried out with 100% water then with water containing 5% increment of methanol till 100% methanol. Fractions 250 ml were collected similar fractions were pooled together, evaporated to dryness whereby 12 fractions (F1-F12) were obtained. The main spots were mainly eluted in fraction 2&3 (1.5 gm.) (sub-fraction 1).
This sub-fraction 1 was rechromatographed on (150 gm.) of silica column, gradient elution was carried out with 100% dichloromethane then with ethyl acetate 10% increment till 100% ethyl acetate, gradient elution was carried out with 10% increment of methanol till 100% methanol each fraction 400 ml. The collected fractions were screened by TLC using solvent system S3 and similarly visualized Similar fractions were polled together to give 16 fractions, (F8-F13) were shown to contain the main spots (sub-fraction 2).
The sub-fraction 2 (0.8gm.) was chromatographed on (80 gm.) of silica column, gradient elution was started with 100% dichloromethane followed by dichloromethane containing increasing amount of methanol by 5%. Sub fractions (100ml, each) were collected, monitored by TLC using solvent system S3 and pooled based on similarity of chromatographic profile, fraction number 8 was contain the main spot (sub fraction 3)
This sub-fraction 3 (0.4 gm.) was rechromatographed on (100gm.) of LH20 column, elution was carried out with methanol 100% each fraction 15ml. The fractions were screened by TLC and similar fractions combined together.
1H NMR was acquired for the different sub fractions which were similar by TLC and 1H NMR and all were combined together and was subjected to LH20 column using system methanol: dichloromethane 90:10 each fraction 5ml. TLC screening and 1H NMR for all sub-fractions showed similar pattern and were pooled together and was subjected to another LH20 column. Elution was carried out with methanol: H2O (90:10), all sub fractions were similar by TLC and 1H NMR, so all fractions combined together (alkaloid mixture).
By using 13C NMR (400 MHz, DMSO, ppm) for extensive analysis for each peak. We could conclude that it contains four similar of alkaloids, are related to the alkaloids Oleracein A, Oleracein B, Oleracein C and Oleracein D which were isolated before from Portulaca oleracea.
6. Nutritional value study of Portulaca oleracea plant.
Portulaca oleracea plant is a very fleshy plant contains about 90% of moisture in fresh plant.
Portulaca oleracea plant contain great nutritional value that make it one of the more important food of the future, it contains high level of proteins (26%), carbohydrate (17.82%), fat (3.37%) from dried sample also contain Ca++ (1.58%), P+++ (00.27%), Fe++ (00.90%), minerals as Zn++ (40.90 ppm), Cu++ (18.48 ppm) and contain high level of vitamins as β- Carotene (20.126 ppm), vitamin E (1.40 ppm), vitamin B2 (2 ppm) and vitamin B1 (0.37 ppm).
Part II: Biological study of Portulaca oleracea plant.
1. Pharmacological activities
1.1. Toxicological study:
The tested extracts are nontoxic and safe and that may explain its extensive utilization in traditional medicine.
1.2. Acute anti-inflammatory activity:
The total methanolic extract of Portulaca oleracea has antiinflammatory activity but lower than indomethacin.
1.3. Anti-hyperglycemic activity:
The total methanolic extractof Portulaca oleracea has antihyperglycemic activity but lower than metformin.
1.4. Antioxidant activity:
The total methanolic extract of Portulaca oleracea has antioxidant activity but lower than vitamin E.
1.5. Analgesic effect.
The total methanolic extract of Portulaca oleracea has analgesic activity that it is low the number of construction done by acetic acid in male albino rate.
1.6. Hepatoprotective activity:
The total methanolic extract of Portulaca oleracea has hepatoprotective activity as it reduce ALP, AST and ALT liver enzymes.
2. Cytotoxic activity:
The test sample exerts cytotoxic activity against stomach carcinoma, breast carcinoma, cervical carcinoma and colorectal carcinoma cell lines.
The methanolic extract has cytotoxic activity against stomach carcinoma cell line more than doxorubicin however it has cytotoxic activity against others carcinoma cell line less than doxorubicin.
In conclusion, the cytotoxic activity may be due to the presence of phytosterols, unsaturated fatty acids, flavonoids and phenolic compounds.
3. Antimicrobial activity
The results showed that the ethyl acetate fraction of Portulaca oleracea was more active than butanol fraction on Aspergillus fumigatus (RCMB 02568) and Candida albicans (RCMB 05036) fungi while hexane fraction has no activity on fungi.
The effect of ethyl acetate fraction is higher than butanol and hexane fraction on the Gram-positive strains (Streptococcus pneumoniae (RCMB 010010), Bacillis subtilis (RCMB 010067), Gram-negative bacteria strains Pseudomonas aeruginosa (RCMB 010043), Escherichia coli (RCMB 010052) compared to the positive controls.
The MIC was determined against selected strains. The ethyl acetate fraction was more active as antifungal and antibacterial activity than hexane and butanol fraction with less MIC.