الفهرس 
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Abstract
In the current study, Marrubium alysson L.(M. alyssonL.)whole plant was extensively investigated both chemically and biologically. The chemical study included determination of total phenolic and total flavonoid content. The total phenolic content was found to be 50.87 mg/g dry extract (calculated as gallic acid equivalent), while the total flavonoid content was determined as 27.37 mg/g dry extract (calculated as rutin equivalent). Four major active constituents were isolated from the methanolic extract of M. alysson L.and identified as marrubiin, kaempferol, quercetin and rutin. HPLC was applied for quantitative estimation of kaempferol, quercetin and rutin which were calculated as 2.7, 0.29 and 0.71 mg/g of the plant extract, respectively. Additionally, metabolomics profiling of M. alysson L. was performed by LC-MS/MS analysis. Forty compounds were assigned, comprising 23 compounds detected in the positive mode and 17 compounds detected in the negative mode. The crude methanolic extract of M. alysson L. and its phenolic fraction as well as kaempferol, quercetin and rutin were tested for their ability to protect mouse testicles from methotrexate-induced damage.Pre-treatment with M. alysson L. methanolic extract, phenolic fraction and the three tested compounds displayed significant protection which was mediated through the inhibition of apoptosis, inflammation and oxidative stress and down-regulation of miRNA-29a testicular expression.
The current work also included chemical study of the non-polar fraction of M. alyssonL. using GC/MS. A number of 10 fatty acid methyl esters were detected where the unsaponifiable matter included 23 compounds. Marrubiin, as a major chemical constituent and of common occurrence in the genus Marrubium was quantified using HPTLC. Revealing of the spots by anisaldehyde–conc. sulfuric acid improved the sensitivity of the method and increased the range within which a linear relationship between concentration and response occurs. The method was validated according to the ICH guidelines and revealed satisfactory accuracy, precision, robustness and limits of detection and quantification. The concentration of marrubiin in M. alysson L. extract was determined based on the regression equation and found to be 14.09 mg/ g of dry extract. The pure compound marrubiin exhibited promising in vitroacetylcholinesterase inhibitory activity with IC50 value= 52.66 (µM). This result coincide with the docking studies that revealed good binding affinity with binding energy of -19.3 Kcal/mol and formed good binding interaction (1 H-bond with Tyr 124).
Key words:Marrubium alysson L.; HPLC;LC-MS/MS; HPTLC; GC/MS; antioxidant; anti-inflammatory; antiapoptotic; AChE.