<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Noha A Khalil</style></author><author><style face="normal" font="default" size="100%">Amira Abdel Motaal</style></author><author><style face="normal" font="default" size="100%">Khaled Meselhy</style></author><author><style face="normal" font="default" size="100%">Soad M Abdel khalek</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Renin and Angiotensin Converting Enzyme Inhibition of Standardized Bioactive Fractions of Hyphaene thebaica L. Mart Growing in Egypt</style></title><secondary-title><style face="normal" font="default" size="100%">Pharmacognosy Journal</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Antihypertensive</style></keyword><keyword><style  face="normal" font="default" size="100%">Doum</style></keyword><keyword><style  face="normal" font="default" size="100%">HPLC</style></keyword><keyword><style  face="normal" font="default" size="100%">Phenolics</style></keyword><keyword><style  face="normal" font="default" size="100%">standardization</style></keyword><keyword><style  face="normal" font="default" size="100%">Validation</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2018</style></year><pub-dates><date><style  face="normal" font="default" size="100%">June 2018</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://fulltxt.org/article/640</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">622-627</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p style=&quot;text-align: justify;&quot;&gt;&lt;strong&gt;Introduction:&lt;/strong&gt; &lt;em&gt;Hyphaene thebaica&lt;/em&gt; L. fruit is known in Egypt for its antihypertensive activity. However a standardized herbal extract/fraction was never prepared.&lt;strong&gt; Methods:&lt;/strong&gt; A biologically guided fractionation was carried out &lt;em&gt;in-vitro&lt;/em&gt; for the 50% and 70% ethanol extracts of &lt;em&gt;Hyphaene thebaica&lt;/em&gt; L. fruit using the angiotensin converting enzyme (ACE) inhibition and renin inhibition assays. A validated reversed phase HPLC method was developed for the standardization of the active fractions. Results: The ethyl acetate fraction of the 70% extract contained higher percentages of the three bioactive markers chlorogenic acid, quercetin and apigenin (1.940 &amp;plusmn; 0.140%, 2.994 &amp;plusmn; 0.349% and 0.612 &amp;plusmn; 0.0354%, respectively) relative to the ethyl acetate fraction of the 50% extract (1.384 &amp;plusmn; 0.157%, 0.342 &amp;plusmn; 0.0834% and 0.070 &amp;plusmn; 0.00225%, respectively). The butanol fraction of the 70% extract was found to possess the highest antihypertensive activity (93.69 &amp;plusmn; 5.695 % renin inhibition activity at 0.5 mg/mL and IC&lt;sub&gt;50&lt;/sub&gt; of 0.001436 +0.00044 mg/mL for ACE inhibition activity). A standard calibration curve for the three compounds was established at a concentration range of 0.1-50 &amp;mu;g/Ml, they showed good linearity with a correlation coefficient (R&lt;sup&gt;2&lt;/sup&gt;) of (1.00, 1.00 and 0.999; respectively). A high degree of precision (relative standard deviation values &amp;lt;5%) was achieved. The limits of detection for the three compounds were 0.428, 0.368 and 0.849; respectively, while the limits of quantitation were 1.29, 1.11 and 2.57, respectively. &lt;strong&gt;Conclusions:&lt;/strong&gt; Current results showed that the butanol fraction of the 70% extract revealed the highest antihypertensive activity through ACE and renin inhibition mechanisms. In addition, recorded observations concerning linearity of the used bioactive markers offer a support for the possible utility of the tested fractions as potent standardized antihypertensive drugs.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><work-type><style face="normal" font="default" size="100%">Original Article</style></work-type><section><style face="normal" font="default" size="100%">622</style></section><auth-address><style face="normal" font="default" size="100%">&lt;p style=&quot;text-align: justify;&quot;&gt;&lt;strong&gt;Noha A Khalil&lt;sup&gt;1*&lt;/sup&gt;, Amira Abdel Motaal&lt;sup&gt;2,3&lt;/sup&gt;, K M Meselhy&lt;sup&gt;3&lt;/sup&gt;, Soad M Abdel Khalek&lt;/strong&gt;&lt;sup&gt;&lt;strong&gt;4&lt;/strong&gt; &lt;/sup&gt;&lt;/p&gt;
&lt;p style=&quot;text-align: justify;&quot;&gt;&lt;sup&gt;1&lt;/sup&gt;Department of Pharmacognosy, Faculty of Pharmacy, Misr International University, EGYPT.&lt;/p&gt;
&lt;p style=&quot;text-align: justify;&quot;&gt;&lt;sup&gt;2&lt;/sup&gt;Department of Pharmacognosy, College of Pharmacy, King Khaled University, Abha, KINGDOM OF SAUDI ARABIA.&lt;/p&gt;
&lt;p style=&quot;text-align: justify;&quot;&gt;&lt;sup&gt;3&lt;/sup&gt;Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, EGYPT.&lt;/p&gt;
&lt;p style=&quot;text-align: justify;&quot;&gt;&lt;sup&gt;4&lt;/sup&gt;Department of Pharmacognosy, Faculty of Pharmacy, Nahda University, BeniSuef, Helwan University, EGYPT.&lt;/p&gt;</style></auth-address></record></records></xml>