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Title: Potential chemopreventive activity of Doash (Origanum majorana L.), a Saudi Arabian herbal tea
Author: Khan, Jehan Abdulmomen
ISNI:       0000 0004 2749 9171
Awarding Body: University of Surrey
Current Institution: University of Surrey
Date of Award: 2012
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Bioactive compounds from plant origin have the potential to subside the biochemical imbalances induced by various toxins associated with mutagenesis and carcinogensis. Therefore new strategy are interested in finding a potent phytotherapeutic agent with non toxic properties. The goal of the present study to evaluate the potential of Doash-leaves water extracts Origanum majorana (2% w/v) as antimutagenic and anticarcinogenic effects against known mutagens classes (heterocyclic amines, polycyclic aromatic hydrocarbons, nitrosoamines and direct acting carcinogens) in vivo and in vitro. The antimutagenic activity was determined by Ames test using different strains of Salmonella Typhimurium. Results obtained showed that, Doash extract possesses powerful antimutagenic against different mutagene. In vivo study revealed that treatment of rats with Doash extracts for one day or 30 days caused a decrease in hepatic cytochrome P450 enzymes such as CYP2B, CYP2E1 and CYP1A, the latter P450 subfamily being closely associated with the inhibition of chemical carcinogens inactivation. Aqueous Doash tea extract diminishes the excretion of indirect acting mutagens in rats treated with (2-Amino-3-methylimidiazol-[4,50-f]quinoline) IQ or (2-hydroxyamino-3-methyl-3H-imidazo[4,5,f] quinoline) PhIP; the antimutagenic effect associated with elevation of hepatic CYP1A2 expression which is involved in the metabolism of carcinogens (IQ and PhIP). HPLC/MS analysis of Doash extract showed that a highest peak related to high terpens contents. Based on these records, it appears that Doash tea extract can in vivo affect the mutagenicity of various structurally diverse promutagens including many food-borne carcinogen, by decreasing cytochrome P450-mediated activation. It was concluded that, daily intake of Doash tea may protect against the conversion of promutagene to mutagene and scavenging carcinogen from environmental contact. More study is needed to examine the mechanistic action of active ingredients of Doash extract fractions on cellular and molecular level.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available