الفهرس 
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Abstract
Silybum Marianum (L.) Gaertn. Occur In Two Varieties In Egypt; The Most Abundant One Is Variety Marianum With Purple Corollas And The Less Abundant Type Is Variety Albiflorum With White Corollas (Boulos, 2002). S. Marianum Var. Marianum Is A Medicinally-Valuable Plant That Have Multiple Health Benefits. Its Medicinal Properties Are Attributed To Antioxidant And Radical-Scavenging Activity Of Silymarin. Seven Major Flavonolignans Were Isolated from Silymarin (Silybins A & B, Isosilybins A & B, Silychristin A, Isosilychristin, And Silydianin) And Considered As Silymarin Marker Compounds For Quantitation Studies. To The Best Of Our Knowledge Limited In Vitro And No In Vivo Studies Were Performed On S. Marianum Var. Albiflorum.
Part I: Phytochemical Study
Chapter I: Phytochemical Study Of The Pericarp
Phytochemical Study Of The Pericarp Of S. Marianum Var. Marianum Lead To Isolation Of Silibinin, Isosilibinin, Silydianin, Silyamandin, Dehydrosilychristin And Silychristin A. Silyamandin Was Proposed To Be A Natural Compound Depending On HPLC And 1H NMR Analysis That Was At Contrast With The Previous Postulation That Silyamandin Is An Artifact Formed from Silydianin Oxidative Coupling. Phytochemical Study Of The Pericarp Of S. Marianum Var. Albiflorum Led To Isolation Of 5,7-Dihydroxy chromone, Homoeriodictyol Isosilandrin A And B, Silandrin A And B And Silyhermin. Isosilandrin And Silandrin Were Proved To Be Diastereomeric Mixture
Chapter II: Phytochemical Study Of The Lipoidal Content
Studying Lipoidal Content Of S. Marianum Varieties Using Qnmr Revealed That The Amount Of Unsaturated Fatty Acids Was Higher Compared To Saturated Ones In Both Varieties. Linoleic Acid (48.29:65.60%) Was Found To Be The Major Component In The Purple Variety While Oleic Acid (44.50%) Was The Major One In The White Variety. Linolenic Acid (18.43%) Was Detected In White-Flowered Silybum Only.
Chapter III: 17 Insights Into The Biosynthesis Of Flavonolignans In S. Marianum
Principal Component Analysis Revealed Positive Correlations Between Silybin A, Silybin B, And Silychristin And Silydianin With Isosilychristin And Isosilybin B, In Addition To Correlation Between Silyamandin With Isosilychristin And Silydianin Content That Could Be Explained By The Involvement Of The Same Precursor (Flavonoid Radical) As Intermediates In Flavonolignans Biosynthesis. Hypothetical Biosynthetic Scheme In Which The Last Three Flavonolignans Share Flavonoid Radical Has Been Developed.
Part II: Silymarin Production
Chapter I: Optimization Of Silymarin Extraction Using RSM
RSM Was Used To Determine The Optimal Conditions For Silymarin Extraction from The Pericarp Using Heat Reflux Method Depending On UV And Qhnmr Analysis. The Optimal Extraction Conditions For Maximum Silymarin Yield Were Temperature Of 115-117°C For Time Duration Of 64-69 Min Using Methanol. On Comparing With Pharmacopeial Method, Heat Reflux Is Simple, Rapid And Do Not Need Sample Pre-Treatment (Defatting Step), Reduce Chemical Consumption And Waste Production, Which Is Important from Both The Environmental And Economic Points Of View. All These Advantage Make Heat Reflux Method Very Attractive For Application In Industry.
Chapter II: Cultivation Of Silybum Marianum Using Hydroponic Culture
Possibility Of Hydroponic Culture Of Milk Thistle Using A Nutrient Film Technique System And Effect Of Salicylic Acid (100, 200 And 400 µm) On Flavonolignans Production Was Studied. The Results Of Elicitation With Salicylic Acid At 200 µm Increased Production Of Total Flavonolignans (1.7-Fold By Qhnmr And 1.6-Fold By HPLC) Higher Than The Control Cultures.
Part III: Biological Study
Quantitative Determination Of Flavonolignans Content In The Extracts Used For Assessing Biological Activity Was Estimated Using Qnmr. The Results Showed That Total Flavolignans Content In Var. Albiflorum (541.24 µg Silibinin / Mg Extract) Was Higher Than In Var. Marianum (490.88 µg Silibinin / Mg Extract).
Chapter I: Α-Amylase Inhibitory Activity
We Studied Inhibition Of Α-Amylase Activity For The Fruit Extract Of The White-Flowered Silybum Extract Compared To Standard Silymarin. The Extract Showed Nearly Double The Activity Of Silymarin (Sigma-Aldrich Co.).
Chapter II: In Vitro Cytotoxic Activity
Cytotoxic Activity Of White-Flowered S. Marianum Fruits Extract, Isosilandrin And Silyhermin Compared To Standard Silymarin Was Carried Out Against Human Cancer Cell Line (Hep-G2) And Normal Human Cell Line (HFB-4) Using SRB. The Result Showed That White-Flowered Silybum Extract And The Tested Flavonolignans Are Four Fold Safer On HFB-4 Cells Than Standard Silymarin. White-Flowered S. Marianum Extract Have Comparable Activity To Standard Silymarin But More Cytotoxic Activity Than Isolated Flavonolignans Against Hep-G2.
Chapter III: In Vivo Antioxidant And Hepatoprotective Activities
In Vivo Antioxidant And Hepatoprotective Activities Of White-Flowered S. Marianum Fruits Extract Against Paracetamol-Induced Hepatotoxicity Compared To Standard Silymarin Was Carried Out. The Results Proved Safety Of The Extract To Liver Tissues At Dose Level Of 200 Mg/Kg. Antioxidant And Hepatoprotective Effects Produced By White-Flowered Silybum Extract Were Better Than That Exerted By The Standard Silymarin At The Same Dose Level.
Figure 82: Chemical Structures Of Isolated Compound from Silybum Marianum Var. Marianum.
Figure 83: Chemical Structures Of Isolated Compound from Silybum Marianum Var. Albiflorum.
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BOULOS, L. (2002) Flora Of Egypt: Volume Three (Verbenaceae-Compositae), Pp. 157-159., Al Hadara Publishing, Cairo.