Name: extraction and purification of polyphenols from freeze-dried berry powder for the treatment of vascular smooth muscle cells in vitro
Uploaded: 2017-07-05T14:00:00
Description: Watch this Scientific Journal Video about Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro at JoVE.com

This work was funded by the American Heart Association (14GRNT20180028) and the Florida State University Council on Research and Creativity (COFRS).

1. Preparation of Reagents
<ol>
	<li>Prepare 80% ethanol (100 mL) by mixing 80 mL of absolute ethanol (molecular biology-grade) and 20 mL of cell culture-grade sterile water.</li>
	<li>To prepare polyphenol extract (10 mg/mL), weigh 10 mg of CE or PE. Add 1 mL of plain Dulbecco&#39;s Modified Eagle Medium (DMEM) under a cell culture hood. Vortex the solution. Aliquot in 200-&#181;L portions and store at -20 &#176;C.</li>
	<li>Prepare lysis buffer.
	<ol>
		<li>Add 5 mL of 1 M HEPES stock solution (pH 7.4; 50 mM final), ...

<ol>
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E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protective+effects+of+a+blueberry+extract+in+acute+inflammation+and+collagen-induced+arthritis+in+the+rat.">Protective effects of a blueberry extract in acute inflammation and collagen-induced arthritis in the rat.</a> Biomed Pharmacother. 83, 1191-1202 (2016).</li><li>Daglia, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polyphenols+as+antimicrobial+agents.">Polyphenols as antimicrobial agents.</a> Curr Opin Biotechnol. 23 (2), 174-181 (2012).</li><li>H&#252;gel, H. M., Jackson, N., May, B., Zhang, A. L., Xue, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polyphenol+protection+and+treatment+of+hypertension.">Polyphenol protection and treatment of hypertension.</a> Phytomedicine. 23 (2), 220-231 (2016).</li><li>Niedzwiecki, A., Roomi, M. W., Kalinovsky, T., Rath, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anticancer+Efficacy+of+Polyphenols+and+Their+Combinations.">Anticancer Efficacy of Polyphenols and Their Combinations.</a> Nutrients. 8 (9), E552 (2016).</li><li>Kresty, L. A., Mallery, S. R., Stoner, G. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Black+raspberries+in+cancer+clinical+trials:+Past,+present+and+future.">Black raspberries in cancer clinical trials: Past, present and future.</a> J Berry Res. 6 (2), 251-261 (2016).</li><li>Hertog, M. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flavonoid+intake+and+long-term+risk+of+coronary+heart+disease+and+cancer+in+the+seven+countries+study.">Flavonoid intake and long-term risk of coronary heart disease and cancer in the seven countries study.</a> Arch Intern Med. 155 (4), 381-386 (1995).</li><li>Peterson, J. J., Dwyer, J. T., Jacques, P. F., McCullough, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Associations+between+flavonoids+and+cardiovascular+disease+incidence+or+mortality+in+European+and+US+populations.">Associations between flavonoids and cardiovascular disease incidence or mortality in European and US populations.</a> Nutr Rev. 70 (9), 491-508 (2012).</li><li>Cassidy, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+anthocyanin+intake+is+associated+with+a+reduced+risk+of+myocardial+infarction+in+young+and+middle-aged+women.">High anthocyanin intake is associated with a reduced risk of myocardial infarction in young and middle-aged women.</a> Circulation. 127 (2), 188-196 (2013).</li><li>Jacques, P. F., Cassidy, A., Rogers, G., Peterson, J. J., Dwyer, J. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dietary+flavonoid+intakes+and+CVD+incidence+in+the+Framingham+Offspring+Cohort.">Dietary flavonoid intakes and CVD incidence in the Framingham Offspring Cohort.</a> Br J Nutr. 114 (9), 1496-1503 (2015).</li><li>Aghababaee, S. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+blackberry+(Morus+nigra+L.)+consumption+on+serum+concentration+of+lipoproteins,+apo+A-I,+apo+B,+and+high-sensitivity-C-reactive+protein+and+blood+pressure+in+dyslipidemic+patients.">Effects of blackberry (Morus nigra L.) consumption on serum concentration of lipoproteins, apo A-I, apo B, and high-sensitivity-C-reactive protein and blood pressure in dyslipidemic patients.</a> J Res Med Sci. 20 (7), 684-691 (2015).</li><li>Jeong, H. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+Rubus+occidentalis+extract+on+blood+pressure+in+patients+with+prehypertension:+Randomized,+double-blinded,+placebo-controlled+clinical+trial.">Effects of Rubus occidentalis extract on blood pressure in patients with prehypertension: Randomized, double-blinded, placebo-controlled clinical trial.</a> Nutrition. 32 (4), 461-467 (2016).</li><li>Jia, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+antihypertensive+effect+of+ethyl+acetate+extract+from+red+raspberry+fruit+in+hypertensive+rats.">The antihypertensive effect of ethyl acetate extract from red raspberry fruit in hypertensive rats.</a> Pharmacogn Mag. 7 (25), 19-24 (2011).</li><li>Feresin, R. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blackberry,+raspberry+and+black+raspberry+polyphenol+extracts+attenuate+angiotensin+II-induced+senescence+in+vascular+smooth+muscle+cells.">Blackberry, raspberry and black raspberry polyphenol extracts attenuate angiotensin II-induced senescence in vascular smooth muscle cells.</a> Food Funct. 7 (10), 4175-4187 (2016).</li><li>Pergola, C., Rossi, A., Dugo, P., Cuzzocrea, S., Sautebin, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+nitric+oxide+biosynthesis+by+anthocyanin+fraction+of+blackberry+extract.">Inhibition of nitric oxide biosynthesis by anthocyanin fraction of blackberry extract.</a> Nitric Oxide. 15 (1), 30-39 (2006).</li><li>Lu, H., Li, J., Zhang, D., Stoner, G. D., Huang, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+mechanisms+involved+in+chemoprevention+of+black+raspberry+extracts:+from+transcription+factors+to+their+target+genes.">Molecular mechanisms involved in chemoprevention of black raspberry extracts: from transcription factors to their target genes.</a> Nutr Cancer. 54 (1), 69-78 (2006).</li><li>Kim, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aqueous+extract+of+unripe+Rubus+coreanus+fruit+attenuates+atherosclerosis+by+improving+blood+lipid+profile+and+inhibiting+NF-&#954;B+activation+via+phase+II+gene+expression.">Aqueous extract of unripe Rubus coreanus fruit attenuates atherosclerosis by improving blood lipid profile and inhibiting NF-&#954;B activation via phase II gene expression.</a> J Ethnopharmacol. 146 (2), 515-524 (2013).</li><li>Wang, J., Mazza, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+anthocyanins+and+other+phenolic+compounds+on+the+production+of+tumor+necrosis+factor+alpha+in+LPS/IFN-gamma-activated+RAW+264.7+macrophages.">Effects of anthocyanins and other phenolic compounds on the production of tumor necrosis factor alpha in LPS/IFN-gamma-activated RAW 264.7 macrophages.</a> J Agric Food Chem. 50 (15), 4183-4189 (2002).</li><li>Pascual-Teresa, S., Moreno, D. 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Polyphenols isolated from berries contain distinct compositions. The ethanol-based extraction protocol described here allowed for the identification of different levels of phenolic acids and flavonoids present in crude and purified polyphenol extracts of BL (Table 1). CE was enriched in gallic acid, ferulic acid, 4-O-caffeoylquinic acid, and 5-O-caffeoylquinic acid. The purification process did not significantly alter the levels of gallic acid and p-coumaric acid. However, it increased the levels of 3-<e...

Polyphenols are compounds containing at least one phenolic ring in their structure and are abundantly present in the plant kingdom1. Humans have been consuming plants for millennia for medicinal purposes without being aware of the existence of such compounds2. Many fruits and vegetables have some shared polyphenolic compounds, albeit with different quantities, including flavonoids, stilbenes, and phenolic acids3. Although polyphenols are often associated with colorful fruits and vegetables, this is not strictly true. For example, zeaxanthin and xanthine are present in vegetables that are not highly colorful, such as onions and garlic, which are from the family of scallions and are associated with numerous health benefits4. Aside from being associated with several health benefits5, polyphenols also serve plants by protecting them from insects and ultraviolet radiation2. Polyphenols are commonly found in the human diet and are considered powerful antioxidants, as they can scavenge Reactive Oxygen Species (ROS)6,7,8. They also have anti-inflammatory9, antimicrobial10, anti-hypertensive11, and anti-carcinogenic12,13 properties.
Epidemiological studies demonstrate an inverse association between the consumption of flavonoids and cardiovascular disease (CVD) incidence16,17 and mortality14,15. Berries are widely consumed in the US and have high amounts of polyphenols, including flavonoids. For instance, consumption of blackberry (BL) juice (300 mL/d) for eight weeks significantly decreased systolic blood pressure in dyslipidemic patients18. Jeong et al.19 reported that pre-hypertensive men and women consuming 2.5 g of black raspberry (BRB) extract per day had lower 24-h and nighttime blood pressure compared to those consuming a placebo. Raspberries (RB) decreased blood pressure while increasing the expression of superoxide dismutase (SOD) in spontaneously hypertensive rats20. It has recently been shown that BL, RB, and BRB reduce the levels of ROS and senescence induced by angiotensin II (Ang II) in Vascular Smooth Muscle Cells (VSMCs)21. In addition, the anthocyanin fraction from BL extract reduced the expression of inducible nitric oxide synthase (iNOS) and inhibited the activity of Nuclear Factor kappa B (NF-&#954;B) and extracellular signal-regulated kinase (ERK) in lipopolysaccharide (LPS)-stimulated J774 cells22. BRB extracts decreased the NF-&#954;B activation and cyclooxygenase 2 (COX-2) expression in vitro 23, improved the lipid profile, and prevented atherosclerosis lesion formation in mice fed a high-fat diet24. Anthocyanins, which are considered the most abundant flavonoids in berries, modulate the inflammatory response in LPS-stimulated RAW 264.7 macrophages by decreasing Tumor Necrosis Factor alpha (TNF-&#945;) production25 and decrease the proliferation and migration of VSMCs26.
Since there has been growing interest in understanding the role of polyphenols in human health and disease, it is important to optimize the extraction method. Solvent extraction is widely used for that purpose, as it is cost-effective and easily reproducible. In this study, a solvent extraction was used with ethanol, along with an ultrasonic-assisted extraction method, which was adapted from Kim and Lee27. The purification and fractionation of crude extracts (CE) using chloroform and ethyl acetate were performed to obtain the purified extract (PE) fraction that was adapted from Queires et al28. Furthermore, the efficacy of crude versus purified polyphenol extracts from BL at reducing the basal phosphorylation of ERK1/2 were compared, and representative examples of the inhibitory effect of purified BL polyphenol extract on Ang II-induced signaling reductions in VSMCs were provided.

<table border="0" cellpadding="0" cellspacing="0" width="971">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Angiotensin II</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">A9525-10MG</td>
			<td style="width:343px;">Treatment of VSMCs</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">&#946;-actin</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">A2228</td>
			<td>Primary antibody (1:5000)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Blackberry fruit</td>
			<td style="width:157px;">Mercer Foods</td>
			<td style="width:168px;"></td>
			<td>Freeze-dried blackberry powder</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Catalase&#160;</td>
			<td style="width:157px;">Calbiochem</td>
			<td style="width:168px;">219010</td>
			<td>Primary antibody (1:1000)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Chloroform</td>
			<td style="width:157px;">Biotech Grd, Inc.</td>
			<td style="width:168px;">97064-678</td>
			<td>Preparation of purified polyphenol extracts</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DMEM</td>
			<td style="width:157px;">Mediatech, Inc.</td>
			<td style="width:168px;">10-014-CV</td>
			<td>Culture of VSMCs</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ethanol (absolute molecular biology grade)</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">E7023-500ML</td>
			<td>Preparation of polyphenol extracts&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ethylacetate</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">439169</td>
			<td>Preparation of purified polyphenol extracts</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:303px;">ERK1/2</td>
			<td style="width:157px;">Cell Signaling Technology, Inc.</td>
			<td style="width:168px;">9102S</td>
			<td>Primary antibody (1:500)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">EDTA, 500 mM, pH 8.0</td>
			<td style="width:157px;">Teknova, Inc.</td>
			<td style="width:168px;">E0306</td>
			<td>Lysis buffer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Freeze-Dryer</td>
			<td style="width:157px;">Labconco</td>
			<td style="width:168px;">VirTis Benchtop K</td>
			<td>Preparation of polyphenol extracts</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">FBS</td>
			<td style="width:157px;">Seradigm</td>
			<td style="width:168px;">1400-500</td>
			<td>Cell culture</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">HEPES</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">H3375</td>
			<td>Lysis buffer&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">NaCl</td>
			<td style="width:157px;">EMD Millipore, Inc.</td>
			<td style="width:168px;">7760</td>
			<td>Lysis buffer</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">NaF</td>
			<td style="width:157px;">J.T.Baker, Inc.</td>
			<td style="width:168px;">3688-01&#160;</td>
			<td>Lysis buffer</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:303px;">Na3VO4</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">450243</td>
			<td>Lysis buffer</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:303px;">Na4P2O7 , decahydrate</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">S-9515</td>
			<td>Lysis buffer</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:303px;">phospho ERK1/2&#160;</td>
			<td style="width:157px;">Cell Signaling Technology, Inc.</td>
			<td style="width:168px;">9101S</td>
			<td>Primary antibody (1:1000)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Protease inhibitor cocktail</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">P8340-5ml</td>
			<td>Lysis buffer</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:303px;">Protein assay dye reagent</td>
			<td style="width:157px;">Bio-Rad Laboratories, Inc.</td>
			<td style="width:168px;">500-0006</td>
			<td>Protein concentration Measurement</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">PVDF transfer membrane</td>
			<td style="width:157px;">Thermo Scientific, Inc.</td>
			<td style="width:168px;">88518</td>
			<td>Western blots</td>
		</tr>
		<tr height="20">
			<td height="41" style="height:41px;width:303px;">Rotatory Evaporator</td>
			<td style="width:157px;">Buchi Labortechnik</td>
			<td style="width:168px;">Rotavapor 
			R3000</td>
			<td>Preparation of polyphenol extracts</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sterile water</td>
			<td style="width:157px;">Mediatech, Inc.</td>
			<td style="width:168px;">25-055-CV</td>
			<td>Preparation of polyphenol extracts</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Sonicator</td>
			<td style="width:157px;">QSonica, LLC</td>
			<td style="width:168px;">Q125</td>
			<td>Preparation of cell extracts</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">SOD2</td>
			<td style="width:157px;">Enzo Life Sciences, Inc.</td>
			<td style="width:168px;">ADI-SOD-110-F</td>
			<td>Primary antibody (1:1000)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Triton-X-100</td>
			<td style="width:157px;">Sigma-Aldrich, Inc.</td>
			<td style="width:168px;">X100</td>
			<td>Western blots</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:303px;">Whatman #2 filter paper</td>
			<td style="width:157px;">GE Healthcare, Inc.</td>
			<td style="width:168px;">28317-241</td>
			<td>Preparation of polyphenol extracts</td>
		</tr>
	</tbody>
</table>

extraction and purification of polyphenols from freeze-dried berry powder for the treatment of vascular smooth muscle cells in vitro

Epidemiological studies indicate that increased flavonoid intake correlates with decreased mortality due to cardiovascular diseases (CVD) in the United States (US) and Europe. Berries are widely consumed in the US and have a high polyphenolic content. Polyphenols have been shown to interact with many molecular targets and to exert numerous positive biological functions, including antioxidant, anti-inflammatory, and cardioprotective effects. Polyphenols isolated from blackberry (BL), raspberry (RB), and black raspberry (BRB) reduce oxidative stress and cellular senescence in response to angiotensin II (Ang II). This work provides a detailed description of the protocol used to prepare the polyphenol extracts from freeze-dried berries. Polyphenol extractions from freeze-dried berry powder were performed using 80% aqueous ethanol and an ultrasonic-assisted extraction method. The crude extract was further purified and fractionated using chloroform and ethyl acetate, respectively. The effects of both crude and purified extracts were tested on Vascular Smooth Muscle Cells (VSMCs) in culture.

It has been previously demonstrated that polyphenol extracts isolated from BL, RB, and BRB reduced the senescence of VSMCs in response to Ang II21. It has been shown that these purified polyphenol extracts modulate Ang II signaling by reducing the phosphorylation of Akt, p38 Mitogen-Activated Protein Kinase (MAPK), and ERK1/2. BL prevents senescence by reducing the expression of the NADPH oxidase (Nox) 1, an enzyme that produces superoxide anions and is strongly up...

Watch this Scientific Journal Video about Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro at JoVE.com

Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro

This work details a step-by-step method to prepare polyphenol-rich extracts from freeze-dried berry powder. In addition, it provides a thorough description of how to use these polyphenol-rich extracts in cell culture in the presence of the peptide hormone angiotensin II (Ang II) using Vascular Smooth Muscle Cells (VSMCs).

Extraction and Purification of Polyphenols from Freeze-dried Berry Powder for the Treatment of Vascular Smooth Muscle Cells In Vitro

Epidemiological studies indicate that increased flavonoid intake correlates with decreased mortality due to cardiovascular diseases (CVD) in the United ...

The overall goal of this protocol is to provide a simple and reproducible method for the extraction and purification of plant polyphenols that could be used to treat cells in the future. This method can help answer key questions regarding the role of function of foods in human health and disease. This ethanol-based and ultrasonic assisted polyphenol extraction is an easy and reproducible method that allows for a higher polyphenol yield.The use of chloroform allows for the removal of sugars, fatty acids, proteins and other molecules while ethyl acetate allows for polyphenol fractionation. This concentrated polyphenol extracts can then be used in vitro and in vivo to study the effects of polyphenols as well as their mechanisms of action on various tissues, including the cardiovascular system, as described here. To begin this procedure, prepare the reagents as outlined in the text protocol.Next, weigh out 10 grams of freeze-dried blackberry powder. Add the berry powder to a one liter round bottom flask containing 100 milliliters of 80%aqueous ethanol. Place the flask in an ultrasonic bath at 25 degrees Celsius.Under continuous nitrogen purging in subdued light, sonicate the mixture for 20 minutes at 42 kilohertz and 135 watts. After this, use a chilled Buchner funnel with vacuum suction to filter the mixture through a number two filter paper. Rinse the filter cake with 50 milliliters of 100%ethanol.Save the filtrate and add the filter cake to a one liter round bottom flask containing 100 milliliters of 80%aqueous ethanol. Then, repeat the extraction process by sonicating, filtering and washing the mixture. Combine the two filtrates in a round bottom flask containing 50 milliliters of 80%aqueous ethanol.Using a rotary evaporator at 62 degrees Celsius and 50 rpm, evaporate the solvent. Continue this until the ethanol no longer evaporates. Next, transfer the sample to a 50 milliliter conical tube.Inject nitrogen gas at the top of the tube for 10 minutes to evaporate any remaining ethanol. Freeze the sample at negative 80 degrees Celsius for at least 24 hours. Then, freeze dry the sample at negative 50 degrees Celsius for approximately eight hours.Store the samples at negative 20 degrees Celsius until ready to use. To begin, weigh the freeze-dried extracted samples. Add approximately 20 milliliters of chloroform to a 100 milliliter beaker with the sample.Using a stir plate, mix the solution for five minutes. Then, pour the mixture into a separating funnel. Let the crude extract decant for one hour at room temperature.After this, discard the bottom layer and collect the aqueous layer into a clean beaker. Add two volumes of ethyl acetate to the beaker. Using a magnetic stir bar, stir the mixture for five minutes at room temperature.Next, use a chilled Buchner funnel with vacuum suction to filter the mixture through number two filter paper. Transfer the filtered sample to a round bottom flask. Using a rotary evaporator at 62 degrees Celsius and 50 rpm, evaporate the ethyl acetate for 30 minutes.After this, freeze dry the sample at negative 50 degrees Celsius for eight hours. Transfer the sample to a 50 milliliter conical tube and store at negative 20 degrees Celsius until ready to use. After culturing the vascular smooth muscle cells, discard the culture medium and wash the cells twice with phosphate buffered saline.Then, add four milliliters of PBS and two milliliters of 0.25%Trypsin-EDTA. Incubate in a carbon dioxide incubator at 37 degrees Celsius for five minutes. After this, transfer the cells to a 15 milliliter centrifuge tube containing two milliliters of complete medium.Centrifuge at 1, 100 times g for five minutes. Discard the supernatant and re-suspend the cell pellet with one milliliter of PBS. Using a hemocytometer, count the cells.Next, in six-well culture plates, seed 50, 000 cells per well. Grow the cells to 90%confluency in complete medium containing 10%fetal bovine serum. Prepare the treatment medium as outlined in the text protocol and store at four degrees Celsius.Then, add 10 milligrams of either crude or purified extract to one milliliter of plain DMEM to prepare a 10 milligram per milliliter stock solution. Store the stock solution in 200 microliter aliquots at negative 20 degrees Celsius. After this, add two milliliters of treatment medium, containing 0.5%fetal bovine serum and the desired concentration of stock solution to the cells.Incubate for three days at 37 degrees Celsius in a humidified 5%CO2 incubator. Then, if treating with hormones or growth factors, starve the cells for at least 24 hours by incubating with treatment medium containing 0.5%fetal bovine serum. After starvation, add the desired hormone, replacing the treatment medium every 24 hours for three days, as detailed in the text protocol.Next, wash the treated cells twice in cold PBS. Lyse the cells using 200 microliters of lysis buffer on ice. Using cell scrapers, collect the cell lysate and transfer to a 1.5 milliliter microcentrifuge tube.Incubate the collected lysate for 20 minutes on ice, vortexing every five minutes. After this, sonicate the cell extracts with three bursts at 125 watts for 10 seconds each, with a two second pause in between each burst. Using a protein assay reagent at 595 nanometers, measure the protein concentration.Mix 50 micrograms of protein with lysis buffer to obtain a maximum total volume of 50 microliters. Add 16 microliters of a 4x Laemmli sample buffer. Then, heat the samples for five minutes at 75 degrees Celsius.Separate samples in 10%SDS-PAGE gels and transfer to PVDF membranes for Western blot analysis with specific antibodies. In this study, an ethanol based extraction is used to identify the different levels of phenolic acids and flavonoids present in crude and purified polyphenol blackberry extracts. While the purification process did not significantly alter the levels of gallic acid or p-coumaric acid, it did increase the levels of 3-O-caffeoylquinic acid from 170.5 to 235.3 ppm and of Quercetin from 24.5 to 95 ppm.In contrast, Ferulic acid and Rutin were lost during the purification of the crude extract. After the extraction, VSMCs were incubated in 50 to 500 micrograms per milliliter of either crude or purified blackberry extract in medium containing 0.5%fetal bovine serum for three days. Both extracts are seen to be effective at reducing the basal phosphorylation of ERK.However, the purified extract is seen to down regulate strongly at 100 micrograms per milliliter, while 400 to 500 micrograms per milliliter of crude extract is required. This suggests that the purified extract's greater efficiency at inhibiting ERK phosphorylation is due to its higher concentrations of polyphenol compounds. After this, VSMCs are treated for 24 hours with 200 micrograms per milliliter of purified blackberry extract before the addition of 100 nanomoles of angiotensin II.As previously reported, the blackberry polyphenol extract reduces angiotensin II induced ERK phosphorylation, but demonstrates no effect on catalase or SOD2 expression.Once mastered, polyphenol extraction can be prepared in a few hours. This technique can aid researchers in the field of functional foods to explore the role of polyphenols in vitro and in animal models. After watching this video, you should be able to extract and purify polyphenols from fruits and vegetables and use the polyphenol extracts to treat cells in culture.We have used this method to demonstrate the role of blackberry polyphenols in preventing aging of aortic vascular smooth muscle cells. This is significant, considering that aging of the vascular system is a major risk factor for the development of cardiovascular diseases.

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Chemistry

Rapid High Throughput Amylose Determination in Freeze Dried Potato Tuber Samples

This protocol describes a high through put colorimetric method that relies on the formation of a complex between iodine and chains of glucose molecules in starch. Iodine forms complexes with both amylose and long chains within amylopectin. After the addition of iodine to a starch sample, the maximum absorption of amylose and amylopectin occurs at 620 and 550 nm, respectively. The amylose/amylopectin ratio can be estimated from the ratio of the 620 and 550 nm absorbance values and comparing them to a standard curve in which specific known concentrations are plotted against absorption values. This high throughput, inexpensive method is reliable and reproducible, allowing the evaluation of large populations of potato clones.&#160;

This protocol describes a high through put colorimetric method that relies on the formation of a complex between iodine and chains of glucose molecules in ...

Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. Diiodomethyllithium is prepared by the deprotonation of diiodomethane with LiHMDS, in a THF/diethyl ether mixture, at -78 &#176;C in the dark. These conditions are essential for the stability of the LiCHI2 reagent generated. The subsequent dropwise addition of N-Ts aldimines to the preformed diiodomethyllithium solution affords an amino-diiodide intermediate, which is not isolated. Rapid warming of the reaction mixture to 0 &#176;C promotes cyclization to afford iodoaziridines with exclusive cis-diastereoselectivity. The addition and cyclization stages of the reaction are mediated in one reaction flask by careful temperature control.
Due to the sensitivity of the iodoaziridines to purification, assessment of suitable methods of purification is required. A protocol to assess the stability of sensitive compounds to stationary phases for column chromatography is described. This method is suitable to apply to new iodoaziridines, or other potentially sensitive novel compounds. Consequently this method may find application in range of synthetic projects. The procedure involves firstly the assessment of the reaction yield, prior to purification, by 1H NMR spectroscopy with comparison to an internal standard. Portions of impure product mixture are then exposed to slurries of various stationary phases appropriate for chromatography, in a solvent system suitable as the eluent in flash chromatography. After stirring for 30 min to mimic chromatography, followed by filtering, the samples are analyzed by 1H NMR spectroscopy. Calculated yields for each stationary phase are then compared to that initially obtained from the crude reaction mixture. The results obtained provide a quantitative assessment of the stability of the compound to the different stationary phases; hence the optimal can be selected. The choice of basic alumina, modified to activity IV, as a suitable stationary phase has allowed isolation of certain iodoaziridines in excellent yield and purity.

A protocol for the diastereoselective one-pot preparation of cis-N-Ts-iodoaziridines is described. The generation of diiodomethyllithium, addition to N-Ts aldimines and cyclization of the amino gem-diiodide intermediate to iodoaziridines is demonstrated. Also included is a protocol to rapidly and quantitatively assess the most appropriate stationary phase for purification by chromatography.

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. ...

Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials

Supercritical fluid extraction and drying methods are well established in numerous applications for the synthesis and processing of porous materials. Herein, nitrogen is presented as a novel supercritical drying fluid for specialized applications such as in the processing of reactive porous materials, where carbon dioxide and other fluids are not appropriate due to their higher chemical reactivity. Nitrogen exhibits similar physical properties in the near-critical region of its phase diagram as compared to carbon dioxide: a widely tunable density up to ~1 g ml-1, modest critical pressure (3.4 MPa), and small molecular diameter of ~3.6 &#197;. The key to achieving a high solvation power of nitrogen is to apply a processing temperature in the range of 80-150 K, where the density of nitrogen is an order of magnitude higher than at similar pressures near ambient temperature. The detailed solvation properties of nitrogen, and especially its selectivity, across a wide range of common target species of extraction still require further investigation. Herein we describe a protocol for the supercritical nitrogen processing of porous magnesium borohydride.

Nitrogen is an effective supercritical fluid for extraction or drying processes due to its small molecular size, high density in the near-liquid supercritical regime, and chemical inertness. We present a supercritical nitrogen drying protocol for the purification treatment of reactive, porous materials.

Supercritical fluid extraction and drying methods are well established in numerous applications for the synthesis and processing of porous materials. ...

X-ray Powder Diffraction in Conservation Science: Towards Routine Crystal Structure Determination of Corrosion Products on Heritage Art Objects

The crystal structure determination and refinement process of corrosion products on historic art objects using laboratory high-resolution X-ray powder diffraction (XRPD) is presented in detail via two case studies.
The first material under investigation was sodium copper formate hydroxide oxide hydrate, Cu4Na4O(HCOO)8(OH)2&#8729;4H2O (sample 1) which forms on soda glass/copper alloy composite historic objects (e.g., enamels) in museum collections, exposed to formaldehyde and formic acid emitted from wooden storage cabinets, adhesives, etc. This degradation phenomenon has recently been characterized as &#34;glass induced metal corrosion&#34;.
For the second case study, thecotrichite, Ca3(CH3COO)3Cl(NO3)2&#8729;6H2O (sample 2), was chosen, which is an efflorescent salt forming needlelike crystallites on tiles and limestone objects which are stored in wooden cabinets and display cases. In this case, the wood acts as source for acetic acid which reacts with soluble chloride and nitrate salts from the artifact or its environment.
The knowledge of the geometrical structure helps conservation science to better understand production and decay reactions and to allow for full quantitative analysis in the frequent case of mixtures.

Modern high resolution X-ray powder diffraction (XRPD) in the laboratory is used as an efficient tool to determine crystal structures of long-known corrosion products on historic objects.

The crystal structure determination and refinement process of corrosion products on historic art objects using laboratory high-resolution X-ray powder ...

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

The chemical linking or bioconjugation of proteins to fluorescent dyes, drugs, polymers and other proteins has a broad range of applications, such as the development of antibody drug conjugates (ADCs) and nanomedicine, fluorescent microscopy and systems chemistry. For many of these applications, specificity of the bioconjugation method used is of prime concern. The Michael addition of maleimides with cysteine(s) on the target proteins is highly selective and proceeds rapidly under mild conditions, making it one of the most popular methods for protein bioconjugation.
We demonstrate here the modification of the only surface-accessible cysteine residue on yeast cytochrome c with a ruthenium(II) bisterpyridine maleimide. The protein bioconjugation is verified by gel electrophoresis and purified by aqueous-based fast protein liquid chromatography in 27% yield of isolated protein material. Structural characterization with MALDI-TOF MS and UV-Vis is then used to verify that the bioconjugation is successful. The protocol shown here is easily applicable to other cysteine - maleimide coupling of proteins to other proteins, dyes, drugs or polymers.

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

This protocol details the important steps required for the bioconjugation of a cysteine containing protein to a maleimide, including reagent purification, reaction conditions, bioconjugate purification and bioconjugate characterization.

The chemical linking or bioconjugation of proteins to fluorescent dyes, drugs, polymers and other proteins has a broad range of applications, such as the ...

A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites

The extraction and analysis of catecholamine neurotransmitters in biological fluids is of great importance in assessing nervous system function and related diseases, but their precise measurement is still a challenge. Many protocols have been described for neurotransmitter measurement by a variety of instruments, including high-pressure liquid chromatography (HPLC). However, there are shortcomings, such as complicated operation or hard-to-detect multiple targets, which cannot be avoided, and presently, the dominant analysis technique is still HPLC coupled with sensitive electrochemical or fluorimetric detection, due to its high sensitivity and good selectivity. Here, a detailed protocol is described for the pretreatment and detection of catecholamines with high pressure liquid chromatography with electrochemical detection (HPLC-ECD) in real urine samples of infants, using electrospun composite nanofibers composed of polymeric crown ether with polystyrene as adsorbent, also known as the packed-fiber solid phase extraction (PFSPE) method. We show how urine samples can be easily precleaned by a nanofiber-packed solid phase column, and how the analytes in the sample can be rapidly enriched, desorbed, and detected on an ECD system. PFSPE greatly simplifies the pretreatment procedures for biological samples, allowing for decreased time, expense, and reduction of the loss of targets. 
Overall, this work illustrates a simple and convenient protocol for solid-phase extraction coupled to an HPLC-ECD system for simultaneous determination of three monoamine neurotransmitters (norepinephrine (NE), epinephrine (E), dopamine (DA)) and two of their metabolites (3-methoxy-4-hydroxyphenylglycol (MHPG) and 3,4-dihydroxy-phenylacetic acid (DOPAC)) in infants' urine. The established protocol was applied to assess the differences of urinary catecholamines and their metabolites between high-risk infants with perinatal brain damage and healthy controls. Comparative analysis revealed a significant difference in urinary MHPG between the two groups, indicating that the catecholamine metabolites may be an important candidate marker for early diagnosis of cases at risk for brain damage in infants.

We present a convenient solid-phase extraction coupled to high-pressure liquid chromatography (HPLC) with electrochemical detection (ECD) for simultaneous determination of three monoamine neurotransmitters and two of their metabolites in infants' urine. We also identify the metabolite MHPG as a potential biomarker for the early diagnosis of brain damage for infants.

The extraction and analysis of catecholamine neurotransmitters in biological fluids is of great importance in assessing nervous system function and ...

Nanothermite with Meringue-like Morphology: From Loose Powder to Ultra-porous Objects

The goal of the protocol described in this article is to prepare aluminothermic compositions (nanothermites) in the form of porous, monolithic objects. Nanothermites are combustible materials made up of inorganic fuel and an oxidizer. In nanothermite foams, aluminum is the fuel and aluminum phosphate and tungsten trioxide are the oxidizing moieties. The highest flame propagation velocities (FPVs) in nanothermites are observed in loose powders and FPVs are strongly decreased by pelletizing nanothermite powders. From a physical standpoint, nanothermite loose powders are metastable systems. Their properties can be altered by unintentional compaction induced by shocks or vibrations or by the segregation of particles over time by settling phenomena, which originates from the density differences of their components. Moving from a powder to an object is the challenge that must be overcome to integrate nanothermites in pyrotechnic systems. Nanothermite objects must have both a high open porosity and good mechanical strength. Nanothermite foams meet both of these criteria, and they are prepared by dispersing a nano-sized aluminothermic mixture (Al/WO3) in orthophosphoric acid. The reaction of aluminum with the acid solution gives the AlPO4 &#34;cement&#34; in which Al and WO3 nanoparticles are embedded. In nanothermite foams, aluminum phosphate plays the dual role of binder and oxidizer. This method can be used with tungsten trioxide, which is not altered by the preparation process. It could probably be extended to some oxides, which are commonly used for the preparation of high performance nanothermites. The WO3-based nanothermite foams described in this article are particularly insensitive to impact and friction, which makes them far safer to handle than loose Al/WO3 powder. The fast combustion of these materials has interesting applications in pyrotechnic igniters. Their use in detonators as primers would require the incorporation of a secondary explosive in their composition.

This manuscript describes the synthesis of combustible aluminophosphate matrices by the reaction of orthophosphoric acid (H3PO4) with aluminum nanopowder. When this reaction is carried out with excess aluminum in the presence of tungsten trioxide nanopowder, it leads to a solid, porous nanothermite foam.

The goal of the protocol described in this article is to prepare aluminothermic compositions (nanothermites) in the form of porous, monolithic objects. ...

Separation of Aldehydes and Reactive Ketones from Mixtures Using a Bisulfite Extraction Protocol

The purification of organic compounds is an essential component of routine synthetic operations. The ability to remove contaminants into an aqueous layer by generating a charged structure provides an opportunity to use extraction as a simple purification technique. By combining the use of a miscible organic solvent with saturated sodium bisulfite, aldehydes and reactive ketones can be successfully transformed into charged bisulfite adducts that can then be separated from other organic components of a mixture by the introduction of an immiscible organic layer. Here, we describe a simple protocol for the removal of aldehydes, including sterically-hindered neopentyl aldehydes and some ketones, from chemical mixtures. Ketones can be separated if they are sterically unhindered cyclic or methyl ketones. For aliphatic aldehydes and ketones, dimethylformamide is used as the miscible solvent to improve removal rates. The bisulfite addition reaction can be reversed by basification of the aqueous layer, allowing for the re-isolation of the reactive carbonyl component of a mixture.

Here, we present a protocol to remove aldehydes and reactive ketones from mixtures by a liquid-liquid extraction protocol directly with saturated sodium bisulfite in a miscible solvent. This combined protocol is rapid and facile to perform. The aldehyde or ketone can be re-isolated by the basification of the aqueous layer.

The purification of organic compounds is an essential component of routine synthetic operations. The ability to remove contaminants into an aqueous layer ...

Extraction of Lignin with High &#946;-O-4 Content by Mild Ethanol Extraction and Its Effect on the Depolymerization Yield

Lignin valorization strategies are a key factor for achieving more economically competitive biorefineries based on lignocellulosic biomass. Most of the emerging elegant procedures to obtain specific aromatic products rely on the lignin substrate having a high content of the readily cleavable &#946;-O-4 linkage as present in the native lignin structure. This provides a miss-match with typical technical lignins that are highly degraded and therefore are low in &#946;-O-4 linkages. Therefore, the extraction yields, and the quality of the obtained lignin are of utmost importance to access new lignin valorization pathways. In this manuscript, a simple protocol is presented to obtain lignins with high &#946;-O-4 content by relatively mild ethanol extraction that can be applied to different lignocellulose sources. Furthermore, analysis procedures to determine the quality of the lignins are presented together with a depolymerization protocol that yields specific phenolic 2-arylmethyl-1,3-dioxolanes, which can be used to evaluate the obtained lignins. The presented results demonstrate the link between lignin quality and potential for the lignins to be depolymerized into specific monomeric aromatic chemicals. Overall, the extraction and depolymerization demonstrates a trade-off between the lignin extraction yield and the retention of the native aryl-ether structure and thus the potential of the lignin to be used as the substrate for the production of chemicals for higher-value applications.

Here, we present a protocol to perform ethanol extraction of lignin from several biomass sources. The effect of the extraction conditions on the lignin yield and &#946;-O-4 content are presented. Selective depolymerization is performed on the obtained lignins to obtain high aromatic monomer products.

Lignin valorization strategies are a key factor for achieving more economically competitive biorefineries based on lignocellulosic biomass. Most of the ...

Synthesis and Bioconjugation of Thiol-Reactive Reagents for the Creation of Site-Selectively Modified Immunoconjugates

Maleimide-bearing bifunctional probes have been employed for decades for the site-selective modification of thiols in biomolecules, especially antibodies. Yet maleimide-based conjugates display limited stability in vivo because the succinimidyl thioether linkage can undergo a retro-Michael reaction. This, of course, can lead to the release of the radioactive payload or its exchange with thiol-bearing biomolecules in circulation. Both of these processes can produce elevated activity concentrations in healthy organs as well as decreased activity concentrations in target tissues, resulting in reduced imaging contrast and lower therapeutic ratios. In 2018, we reported the creation of a modular, stable, and easily accessible phenyloxadiazolyl methyl sulfone reagent &#8212; dubbed &#8216;PODS&#8217; &#8212; as a platform for thiol-based bioconjugations. We have clearly demonstrated that PODS-based site-selective bioconjugations reproducibly and robustly create homogenous, well-defined, highly immunoreactive, and highly stable radioimmunoconjugates. Furthermore, preclinical experiments in murine models of colorectal cancer have shown that these site-selectively labeled radioimmunoconjugates exhibit far superior in vivo performance compared to radiolabeled antibodies synthesized via maleimide-based conjugations. In this protocol, we will describe the four-step synthesis of PODS, the creation of a bifunctional PODS-bearing variant of the ubiquitous chelator DOTA (PODS-DOTA), and the conjugation of PODS-DOTA to the HER2-targeting antibody trastuzumab.

In this protocol, we will describe the synthesis of PODS, a phenyoxadiazolyl methyl sulfone-based reagent for the site-selective attachment of cargos to the thiols of biomolecules, particularly antibodies. In addition, we will describe the synthesis and characterization of a PODS-bearing bifunctional chelator and its conjugation to a model antibody.

Maleimide-bearing bifunctional probes have been employed for decades for the site-selective modification of thiols in biomolecules, especially antibodies. ...