Monoamine Oxidase-A Inhibition and Associated Antioxidant Activity in Plant Extracts with Potential Antidepressant Actions

<div>Antioxidant activity associated with MAO inhibition in assays coupling activity of MAO-A with the subsequent oxidation of tetramethylbenzidine (TMB) in the presence H<sub>2</sub>O<sub>2</sub> generated in the reaction of MAO, and horseradish peroxidase (HRP). The graph shows the oxidation of TMB to diimine (absorbance at 450 nm) in control assays (100%), and in the presence of<i> H. perforatum</i> (herbs and flower extracts, 800 <i>μ</i>g/mL),<i> P. harmala</i> seed extracts (0.8 <i>μ</i>g/mL),<i> L. meyenii</i> root (maca) extracts (800 <i>μ</i>g/mL), clorgyline (a standard inhibitor of MAO-A) (25 <i>μ</i>M), and catalase (100 <i>μ</i>g/mL). <svg height="13.9365pt" id="M43" style="vertical-align:-3.834pt" version="1.1" viewbox="-0.0498162 -10.1025 61.6097 13.9365" width="61.6097pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M486 158C486 177 478 202 466 220C413 228 386 236 336 262C386 288 413 297 466 304C478 323 486 347 485 366C470 376 444 381 422 380C389 338 368 319 321 288C323 345 329 372 349 422C339 442 322 461 305 470C289 461 271 442 262 422C281 372 287 345 290 288C243 319 222 338 189 380C167 381 142 376 125 366C125 347 133 322 145 304C198 296 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BioMed Research International

fig6

Figure 6

Figure 6: Monoamine Oxidase-A Inhibition and Associated Antioxidant Activity in Plant Extracts with Potential Antidepressant Actions 