Study of the ACE inhibitory effect of medicinal plants used in Iranian Folk-Medicine as antihypertensive remedy

Angiotensin converting enzyme [ACE] is an exopeptidase which converts angiotensin I to angiotensin II. Angiotensin II causes vasoconstriction and aldosteron secretion and inactivate bradykinin, so ACE has major role on blood pressure regulation. In this study 135 plants used in Persian traditional medicine have been investigated for their angiotensin converting enzyme [ACE] inhibitory activity potential. They were selected on the basis of their usage as antihypertensive, cardiotonics and diuretics. The dried powdered plant material, 1 g was extracted with 10 ml water and ethanol [%96] in ultrasonic bath. The extracts were filtered and concentrated in vacuum except for the water extracts, which were freeze-dried. Test solutions were made by dissolving extract in assay buffer, corresponding to a final concentration of 0.33 mg of crude plant extract in 1 ml test volume. Enzyme assay was performed by HPLC method. Plants exhibiting inhibition levels more then 50% were further tested for the presence of tannins in order to eliminate possible false positives. In total, 52 species out of the 135 [39%] screened, gave more than 50% ACE inhibition. 40 species were found to possess a high ACE inhibiting ability and were low in their tannin content

Review on Cynara scolymus L

Articholce [Cynara Scolymus L.] is one of non- native plants being cultivated in Iran. This plant is mostly used in foods, so that it is probably harmless. In this Article we are going to coucentrate on different stages of its cultivation and the clinical uses of it in relation with some clinical studies

Study of the different solvents on silymarin extraction from milk thistle

The seeds extract of Milk thistle [Silybum marianum [L]Gaertn]is named silymarin It is used widely in the treatment of cirrhosis, diabetes mellitus, and hypercholesterolemia. There are different methods for production of this compound but the best method is patented. In this study, we study the power of different solvents on silymarin production. 10g of three samples [Marzanabad, Golshan and Hungarian samples cultivated in our research farm], powdered and defatted by petroleum ether, the degatted powders were extracted with one of the following solvents: Methanol, ethanol acetone, ethylacetate, and acetonitril. The silymarin content was assayed by HPLC The results showed that methanol is the best solvent in extracting silymarin and all of its components after methanol, acetone and acetonitril had good power, in extracting silymarin and silybin Methanol is the best solvent for silymarin extraction and then acetone and acetonitril could be replaced for it

[Study of angiotensin converting enzyme [ACE] inhibitory effects of main Papaver spp. alkaloids]

Angiotensin converting enzyme [ACE] converts the inactive angiotensin I to [a potent vasoconstrictor and aldosterone releaser] angiotensin II. Inhibitors of ACE are valuable drugs in the treatment of hypertension, and heart failure. These inhibitors have a natural origin and non-peptide drugs were synthesized from the natural lead compounds. However, because of some side effects such as dry cough, many investigators are searching in natural products to find better and more selective lead compounds. There are reports on the interaction between rennin-angiotensin system and endogenous opioid system. Morphine and endogenous opioids have reported to inhibit ACE. In this research we examined the possible inhibitory effects of purified papaver's main alkaloids on the activity of purified rabbit lung ACE. We found that only papaverin at 1 mM inhibited the enzyme by 40%. The Km value of ACE increased while Vmax decreased in papaverin treated samples. We conclude that part of hypotensive effects of papaverin may be related to ACE inhibition, and this compound will be a suitable lead compound for further investigation