Name: extraction and analysis of taiwanese green propolis
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Description: Watch this Scientific Journal Video about Extraction and Analysis of Taiwanese Green Propolis at JoVE.com

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1. Preparation of Ethanol-extracted Compounds
<ol>
	<li>Weigh 10 g of frozen Taiwanese green propolis, which was collected from beehives in Taiwan from May to July, and grind it using the spice grinder. Confirm that whole pieces of Taiwanese green propolis are ground into a fine powder without any large particles.</li>
	<li>Add 100 mL of various concentrations of ethanol (60%, 70%, 80%, 95%, and 99.5%) and water to separate flasks and mix each concentration with 10 g of ground propolis.</li>
	<li>Incubate at 25 &#176;C...

<ol>
	<li>Zabaiou, N., 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=Biological+properties+of+propolis+extracts:+Something+new+from+an+ancient+product.">Biological properties of propolis extracts: Something new from an ancient product.</a> Chemistry and Physics of Lipids. 207 (Pt B), 214-222 (2017).</li><li>Bankova, V. B., De Castro, S. L., Marcucci, M. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Propolis:+Recent+advances+in+chemistry+and+plant+origin.">Propolis: Recent advances in chemistry and plant origin.</a> Apidologie. 31 (1), 3-15 (2000).</li><li>Park, Y. K., Alencar, S. M., Aguiar, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Botanical+origin+and+chemical+composition+of+Brazilian+propolis.">Botanical origin and chemical composition of Brazilian propolis.</a> Journal of Agricultural and Food Chemistry. 50 (9), 2502-2506 (2002).</li><li>Chen, C. N., Wu, C. L., Shy, H. S., Lin, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cytotoxic+prenylflavanones+from+Taiwanese+propolis.">Cytotoxic prenylflavanones from Taiwanese propolis.</a> Journal of Natural Products. 66 (4), 503-506 (2003).</li><li>Chen, C. N., Weng, M. S., Wu, C. L., Lin, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+radical+scavenging+activity,+cytotoxic+effects+and+apoptosis+induction+in+human+melanoma+cells+by+Taiwanese+propolis+from+different+sources.">Comparison of radical scavenging activity, cytotoxic effects and apoptosis induction in human melanoma cells by Taiwanese propolis from different sources.</a> Evidence-Based Complementary and Alternative. 1 (2), 175-185 (2004).</li><li>Chen, C. N., Wu, C. L., Lin, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Apoptosis+of+human+melanoma+cells+induced+by+the+novel+compounds+propolin+A+and+propolin+B+from+Taiwanese+propolis.">Apoptosis of human melanoma cells induced by the novel compounds propolin A and propolin B from Taiwanese propolis.</a> Cancer Letters. 24 (1-2), 218-231 (2007).</li><li>Huang, W. J., 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=Propolin+G,+a+prenylflavanone,+isolated+from+Taiwanese+propolis,+induces+caspase-dependent+apoptosis+in+brain+cancer+cells.">Propolin G, a prenylflavanone, isolated from Taiwanese propolis, induces caspase-dependent apoptosis in brain cancer cells.</a> Journal of Agricultural and Food Chemistry. 55 (18), 7366-7376 (2007).</li><li>Chen, Y. W., Ye, S. R., Ting, C., Yu, Y. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibacterial+activity+of+propolins+from+Taiwanese+green+propolis.">Antibacterial activity of propolins from Taiwanese green propolis.</a> Journal of Food and Drug Analysis. 26 (2), 761-768 (2018).</li><li>Hegazi, A. G., Abd El Hady, F. K., Abd Allah, F. A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical+composition+and+antimicrobial+activity+of+European+propolis.">Chemical composition and antimicrobial activity of European propolis.</a> Zeitschrift f&#252;r Naturforschung. 55 (1-2), 70-75 (2000).</li><li>Sforcin, J. M., Fernandes, A., Lopes, C. A. M., Bankova, V., Funari, S. R. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Seasonal+effect+on+Brazilian+propolis+antibacterial+activity.">Seasonal effect on Brazilian propolis antibacterial activity.</a> Journal of Ethnopharmacology. 73 (1-2), 243-249 (2000).</li><li>Chen, Y. W., 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=Characterization+of+Taiwanese+propolis+collected+from+different+locations+and+seasons.">Characterization of Taiwanese propolis collected from different locations and seasons.</a> Journal of the Science of Food and Agriculture. 88 (3), 412-419 (2008).</li><li>Grange, J. M., Davey, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibacterial+properties+of+propolis+(bee+glue).">Antibacterial properties of propolis (bee glue).</a> Journal of the Royal Society of Medicine. 83 (3), 159-160 (1990).</li><li>Kujumgiev, 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=Antibacterial,+antifungal+and+antiviral+activity+of+propolis+from+different+geographic+origins.">Antibacterial, antifungal and antiviral activity of propolis from different geographic origins.</a> Journal of Ethnopharmacology. 64 (3), 235-240 (1999).</li><li>Krol, W., Scheller, S., Shani, J., Pietsz, G., Czuba, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synergistic+effect+of+ethanol+extract+of+propolis+and+antibiotics+in+the+growth+of+Staphylococcus+aureus.">Synergistic effect of ethanol extract of propolis and antibiotics in the growth of Staphylococcus aureus.</a> Drug Research. 43 (5), 607-609 (1993).</li><li>Lu, L. C., Chen, Y. W., Chou, 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=Antibacterial+and+DPPH+free+radical-scavenging+activities+of+the+ethanol+extract+of+propolis+collected+in+Taiwan.">Antibacterial and DPPH free radical-scavenging activities of the ethanol extract of propolis collected in Taiwan.</a> Journal of Food and Drug Analysis. 11 (4), 277-282 (2003).</li><li>Tosi, B., Donini, A., Romagnoli, C., Bruni, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antimicrobial+activity+of+some+commercial+extracts+of+propolis+prepared+with+different+solvents.">Antimicrobial activity of some commercial extracts of propolis prepared with different solvents.</a> Phytotherapy Research. 10 (4), 335-336 (1996).</li><li>Cunha, I. B. 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=Factors+that+influence+the+yield+and+composition+of+Brazilian+propolis+extracts.">Factors that influence the yield and composition of Brazilian propolis extracts.</a> Journal of the Brazilian Chemical Society. 15 (6), 964-970 (2004).</li><li>Woo, S. O., Hong, I. P., Han, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extraction+properties+of+propolis+with+ethanol+concentration.">Extraction properties of propolis with ethanol concentration.</a> Journal of Apicultural Research. 30 (3), 211-216 (2015).</li><li>Park, Y. K., Ikegaki, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+water+and+ethanolic+extracts+of+propolis+and+evaluation+of+the+preparations.">Preparation of water and ethanolic extracts of propolis and evaluation of the preparations.</a> Bioscience, Biotechnology, and Biochemistry. 62 (11), 2230-2232 (1998).</li><li>Ramanauskien&#279;, K., Ink&#279;nien&#279;, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Propolis+oil+extract:+quality+analysis+and+evaluation+of+its+antimicrobial+activity.">Propolis oil extract: quality analysis and evaluation of its antimicrobial activity.</a> Natural Product Research. 25 (15), 1463-1468 (2011).</li><li>Machado, B. 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=Chemical+composition+and+biological+activity+of+extracts+obtained+by+supercritical+extraction+and+ethanolic+extraction+of+brown,+green+and+red+propolis+derived+from+different+geographic+regions+in+brazil.">Chemical composition and biological activity of extracts obtained by supercritical extraction and ethanolic extraction of brown, green and red propolis derived from different geographic regions in brazil.</a> PLoS One. 11 (1), e0145954 (2016).</li><li>Monroy, Y. M., 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=Brazilian+green+propolis+extracts+obtained+by+conventional+processes+and+by+processes+at+high+pressure+with+supercritical+carbon+dioxide,+ethanol+and+water.">Brazilian green propolis extracts obtained by conventional processes and by processes at high pressure with supercritical carbon dioxide, ethanol and water.</a> The Journal of Supercritical Fluids. 130, 189-197 (2017).</li><li>Popova, M., Chen, C. N., Chen, P. Y., Huang, C. Y., Bankova, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+validated+spectrophotometric+method+for+quantification+of+prenylated+flavanones+in+pacific+propolis+from+Taiwan.">A validated spectrophotometric method for quantification of prenylated flavanones in pacific propolis from Taiwan.</a> Phytochemical Analysis. 21 (2), 186-191 (2010).</li><li>Chen, L. 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=Taiwanese+green+propolis+ethanol+extract+delays+the+progression+of+type+2+diabetes+mellitus+in+rats+treated+with+streptozotocin/high-fat+diet.">Taiwanese green propolis ethanol extract delays the progression of type 2 diabetes mellitus in rats treated with streptozotocin/high-fat diet.</a> Nutrients. 10 (4), e503 (2018).</li></ol>

A study reported that maceration, using various concentrations of ethanol, could be used for Brazilian propolis extraction17; however, the process was time-consuming17. It took at least 10 days to extract the bioactive compounds, such as phenolic content, from Brazilian propolis17. Alternatively, ethanol extraction in combination with heating at 37 &#176;C, 50 &#176;C, or 70 &#176;C for 30 min has been proposed for extracting Brazilian propolis<sup c...

Propolis is a natural resinous mixture produced by the bee species Apis mellifera. Propolis has been widely used since ancient times in folk medicines. A study recently reported that propolis is beneficial for preventing microbial infections and inflammation1. Numerous studies have demonstrated that the main bioactive compounds in propolis are flavonoids, phenolic acid esters, prenylated p-coumaric acids, and diterpenic acids2,3. To date, 10 prenylated flavanone derivatives from Taiwanese green propolis have been identified through high-performance liquid chromatography (HPLC)4,5,6,7. The most abundant among these are propolins C, D, F, and G5,7. The considerable biological effects of Taiwanese green propolis are correlated with its high content of propolins8.
The concentrations of bioactive compounds in propolis vary greatly depending on the season and geographic location from which the propolis is obtained. European propolis mainly contains the flavonoid aglycone and phenolic acids9. The major bioactive compounds in propolis from Brazil are prenylated p-coumaric acids, such as artepillin C10. A study demonstrated that the season is a critical factor for determining the total propolin content in Taiwanese green propolis11. The propolin content in Taiwanese green propolis is highest in summer (May - July) and lowest in winter11. The antibacterial property of propolis has been widely considered to be an indicator of biological activity. Generally, the samples of propolis collected from various regions have exhibited a similar antibacterial property; for example, it is generally effective against almost all gram-positive bacteria and exhibits a limited antibacterial effect against gram-negative bacteria10,12,13. Synergistic interactions between the flavonoids in propolis were demonstrated to have an antibacterial effect14. Similarly, Taiwanese green propolis was reported to have an antimicrobial effect against gram-positive bacteria15. Furthermore, a study also identified an antimicrobial effect from the interactions of propolins in Taiwanese green propolis8.
The characterization of the bioactive compounds in propolis is difficult because its chemical composition can vary according to its source of origin. Therefore, it is necessary to establish a feasible and repeatable method for determining the quality of the Taiwanese green propolis. However, no standard procedure has been established for Taiwanese green propolis extraction and subsequent functional analysis. Several methods that variously apply organic and inorganic solvents have been proposed for propolis extraction16,17,18,19,20. Because propolis is a lipophilic mixture, studies have demonstrated that organic extraction is better than inorganic extraction8,18,19. The total propolin concentration in Taiwanese green propolis and its antibacterial properties are key indicators of the quality of Taiwanese green propolis. Thus, the purpose of this study is to present a protocol for using ethanol as a solvent to extract and characterize the antibacterial properties of Taiwanese green propolis.

<table>
	<tbody>
		<tr>
			<td>ethanol</td>
			<td>Sigma-Aldrich</td>
			<td>E7023</td>
			<td></td>
		</tr>
		<tr>
			<td>Whatman no. 4 filter paper</td>
			<td>Sigma-Aldrich</td>
			<td>WHA1004125</td>
			<td></td>
		</tr>
		<tr>
			<td>methanol</td>
			<td>Sigma-Aldrich</td>
			<td>34860</td>
			<td></td>
		</tr>
		<tr>
			<td>reverse phase RP-18 column</td>
			<td>Phenomenex Inc.</td>
			<td>00G-0234-E0</td>
			<td></td>
		</tr>
		<tr>
			<td>Staphylococcus aureus</td>
			<td>ATCC</td>
			<td>BCRC 10780</td>
			<td></td>
		</tr>
		<tr>
			<td>Escherichia coli</td>
			<td>ATCC</td>
			<td>BCRC 10675</td>
			<td></td>
		</tr>
		<tr>
			<td>tryptic soy broth</td>
			<td>Sigma-Aldrich</td>
			<td>22092</td>
			<td></td>
		</tr>
		<tr>
			<td>nutrient broth</td>
			<td>Sigma-Aldrich</td>
			<td>70122</td>
			<td></td>
		</tr>
		<tr>
			<td>dimethyl sulfoxide</td>
			<td>Sigma-Aldrich</td>
			<td>D2650</td>
			<td></td>
		</tr>
		<tr>
			<td>spice grinder</td>
			<td>Waring</td>
			<td>WSG60K</td>
			<td></td>
		</tr>
		<tr>
			<td>microplate Reader</td>
			<td>Molecular Devices</td>
			<td>EMAX PLUS</td>
			<td></td>
		</tr>
		<tr>
			<td>HPLC system</td>
			<td>Agilent</td>
			<td>1200 Series</td>
			<td></td>
		</tr>
		<tr>
			<td>vacuum evaporation</td>
			<td>B&#220;CHI</td>
			<td>Rotavapor R-215</td>
			<td></td>
		</tr>
	</tbody>
</table>

extraction and analysis of taiwanese green propolis

Taiwanese green propolis is rich in prenylated flavonoids and exhibits a broad range of biological activities, such as antioxidant, antibacterial, and anticancer ones. The bioactive compounds of Taiwanese green propolis are propolins, namely C, D, F, and G. The concentration of propolins in Taiwanese green propolis varies depending on the season and geographic location. Thus, it is critical to establish a standard and repeatable procedure for determining the quality of Taiwanese green propolis. Here, we present a protocol that uses ethanol-based extraction, high-performance liquid chromatography, and an antibacterial activity analysis to characterize Taiwanese green propolis quality. This method indicates that 95% and 99.5% ethanol extractions achieve the maximum dry matter yields from Taiwanese green propolis, thereby yielding the highest concentrations of propolins that have antibacterial properties. According to these findings, the present protocol is deemed reliable and repeatable for determining the quality of Taiwanese green propolis.

Positive representative data for the ethanol extraction are presented in Table 1. The dry matter yield from Taiwanese green propolis was positively associated with the concentration of ethanol. The 95% and 99.5% ethanol extracts had the highest dry matter yield from Taiwanese green propolis. The lowest dry matter yield from Taiwanese green propolis occurred when water was used as the extraction solvent. These results indicate that an organic solvent, such as ethanol, perf...

Watch this Scientific Journal Video about Extraction and Analysis of Taiwanese Green Propolis at JoVE.com

Extraction and Analysis of Taiwanese Green Propolis

We present a protocol for using ethanol as a solvent to extract and characterize Taiwanese green propolis that exhibits antibacterial activity.

Taiwanese green propolis is rich in prenylated flavonoids and exhibits a broad range of biological activities, such as antioxidant, antibacterial, and ...

Here, we present the protocol for using ethanol as a solvent to extract and characterize Taiwanese green propolis which inhibit antibacterial activity. This protocol is a reliable and repeatable method for determining the quality of Taiwanese green propolis. Demonstrating procedure will be Chun'Ting Chen and Yi'Hsuan Chien, PhD students from my laboratory.To begin, weigh out 100 grams of Taiwanese green propolis. Using a spice grinder, grind the propolis making sure that the pieces are ground into a fine powder without any large particles. Set out five flasks and add 100 milliliters of various concentrations of ethanol in water to each.Mix 10 grams of ground propolis into the ethanol solution in each flask, and incubate at 25 degrees Celsius with shaking at 250 RPM for 48 hours. After this, use filter paper with a 25 micrometer pore size to filter the ethanol extracts. Using a volumetric flask, reconstitute the filtrates to their original volume of 100 milliliters with 95%ethanol.Store the reconstituted extracts at minus 20 degrees Celsius until ready to use. When ready to prepare the extracts for HPLC, use vacuum evaporation to concentrate 10 milliliters of each extract at 40 degrees Celsius for 10 minutes. Bake the dry matter at 45 degrees Celsius for 24 hours.Then, reconstitute each sample of dry matter with 10 milliliters of 95%ethanol. Using a syringe filter with a 0.22 micrometer pore size, refilter each extract and collect the filtrate for direct analysis with HPLC. To begin establishing a standard curve, prepare one liter of the mobile phase methanol to water solution at a ratio of 88.8 to 11.2.Using the mobile phase solution as a solvent, prepare serial dilutions of the propolin standard concentrations as outlined in the text protocol. Inject 20 microliters of each standard concentration into the reverse phase columns sequentially from the lowest concentration to the highest. Then, set the HPLC column to 30 degrees Celsius, set the waive length of the UV detector to 280 nanometers, and the flow rate to one milliliter per minute, and the recorder time to 20 minutes.Analyze the standards at least three times. After this, use calculation sheet software to plug the measurement response against the concentration resulting in a standard curve with a determined equation and R-squared value. To begin analyzing the extracts, inject 20 microliters of each extract into the reverse phase column.Set the HPLC column to a temperature of 30 degrees Celsius, and a flow rate of one milliliter per minute. Set the waive length of the UV detector to 280 nanometers, and the recorder time to 20 minutes. Analyze the extracts at least three times.Then, use the standard curve to determine the concentration of propolin in each ethanol extract. After preparing the test organisms and ethanol extracts, add 10 microliters of diluted ethanol extract, ranging from 0.156 to 640 micrograms per milliliter into the wells of a 96 well plate. Use broth to adjust the volume in each well to 100 microliters making sure to maintain 5%DMSO in all the dilutions.Next, inoculate 100 microliters of bacterial culture into each well of the 96 well plate. Culture at 37 degrees Celsius for 48 hours. Use a microplate reader at 590 nanometers to analyze the bacterial growth according to turbidity and to determine the minimum inhibitory concentration.After this, inoculate 10 microliters of liquid culture from each well that exhibited to growth onto an agar plate. Incubate at 37 degrees Celsius for 24 hours. Identify the lowest concentration that revealed no visible bacterial growth to determine the bacterial activity.The concentration that completely eliminated cell growth is considered to be the minimum bacterial concentration. In this study, Taiwanese green propolis is extracted with ethanol. The dry matter yield is seemed to be highest when a high concentration of ethanol is used, and lowest when water is used.These results indicate that an organic solvent performs best during this extraction, and that the yield is positively associated with the ethanol concentration. Likewise, the concentration of propolins is seemed to be positively associated with the ethanol concentration during extraction, with the highest yield of propolins being obtained in the 95%and 99.5%ethanol extracts. The antibacterial affects of the ethanol extracts against the S aureus and E coli are then investigated.The average minimum inhibitory concentration for S aureus is seemed to be between 10 and 20 micrograms per milliliter and the average bacterial concentration is seemed to be 20 micrograms per milliliter. Water extracts, however, did not have any antibacterial affect against S aureus. No antibacterial affect is observed for E coli when using either the water or ethanol extracts.One of the key experimental procedure is eschewing the uniformity of Taiwanese green propolis during grinding.

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Measuring the intracellular oxidation/reduction balance provides an overview of the physiological and/or pathophysiological redox status of an organism. Thiols are especially important for illuminating the redox status of cells via their reduced dithiol and oxidized disulfide ratios. Engineered cysteine-containing fluorescent proteins open a new era for redox-sensitive biosensors. One of them, redox-sensitive green fluorescent protein (roGFP), can easily be introduced into cells with adenoviral transduction, allowing the redox status of subcellular compartments to be evaluated without disrupting cellular processes. Reduced cysteines and oxidized cystines of roGFP have excitation maxima at 488 nm and 405 nm, respectively, with emission at 525 nm. Assessing the ratios of these reduced and oxidized forms allows the convenient calculation of redox balance within the cell. In this method article, immortalized human triple-negative breast cancer cells (MDA-MB-231) were used to assess redox status within the living cell. The protocol steps include MDA-MB-231 cell line transduction with adenovirus to express cytosolic roGFP, treatment with H2O2, and assessment of cysteine and cystine ratio with both flow cytometry and fluorescence microscopy.

This protocol describes the assessment of subcellular compartment-specific redox status within the cell. A redox-sensitive fluorescent probe allows convenient ratiometric analysis in intact cells.

Measuring the intracellular oxidation/reduction balance provides an overview of the physiological and/or pathophysiological redox status of an organism. ...

Rapid and Cost-Effective RNA Extraction of Rat Pancreatic Tissue

Regardless of the extraction method, optimized RNA extraction of tissues and cell lines are carried out in four stages: 1) homogenization, 2) effective denaturation of proteins from RNA, 3) ribonuclease inactivation, and 4) removal of contamination from DNA, proteins, and carbohydrates. However, it is very laborious to maintain the integrity of RNA when there are high levels of RNase in the tissue. Spontaneous autolysis makes it very difficult to extract RNA from pancreatic tissue without damaging it. Thus, a practical RNA extraction method is needed to maintain the integrity of pancreatic tissues during the extraction process. An experimental and comparative study of existing protocols was carried out by obtaining 20-30 mg of rat pancreatic tissues in less than 2 minutes and extracting the RNA. The results were assessed by electrophoresis. The experiments were carried out three times for generalization of the results. Immersing pancreatic tissue in RNA stabilization reagent at -80 &#176;C for 24 h yielded high integrity RNA, when the RNA extraction reagent was used as the reagent. The results obtained were comparable to the results obtained from commercial kits with spin column bindings.

The purity and integrity of the isolated RNA is a vital step in RNA dependent assays. Here, we present a practical, rapid, and inexpensive method to extract RNA from a small quantity of undamaged pancreatic tissue.

Regardless of the extraction method, optimized RNA extraction of tissues and cell lines are carried out in four stages: 1) homogenization, 2) effective ...

Ganglioside Extraction, Purification and Profiling

Gangliosides are glycosphingolipids that contain one or more sialic acid residues. They are found on all vertebrate cells and tissues but are especially abundant in the brain. Expressed primarily on the outer leaflet of the plasma membranes of cells, they modulate the activities of cell surface proteins via lateral association, act as receptors in cell-cell interactions and are targets for pathogens and toxins. Genetic dysregulation of ganglioside biosynthesis in humans results in severe congenital nervous system disorders. Because of their amphipathic nature, extraction, purification, and analysis of gangliosides require techniques that have been optimized by many investigators in the 80 years since their discovery. Here, we describe bench-level methods for the extraction, purification, and preliminary qualitative and quantitative analyses of major gangliosides from tissues and cells that can be completed in a few hours. We also describe methods for larger scale isolation and purification of major ganglioside species from brain. Together, these methods provide analytical and preparative scale access to this class of bioactive molecules.

Gangliosides are sialic acid-bearing glycosphingolipids that are particularly abundant in the brain. Their amphipathic nature requires organic/aqueous extraction and purification techniques to ensure optimal recovery and accurate analyses. This article provides overviews of analytic and preparative scale ganglioside extraction, purification, and thin layer chromatography analysis.

Gangliosides are glycosphingolipids that contain one or more sialic acid residues. They are found on all vertebrate cells and tissues but are especially ...

The Extraction of Liver Glycogen Molecules for Glycogen Structure Determination

Liver glycogen is a hyperbranched glucose polymer that is involved in the maintenance of blood sugar levels in animals. The properties of glycogen are influenced by its structure. Hence, a suitable extraction method that isolates representative samples of glycogen is crucial to the study of this macromolecule. Compared to other extraction methods, a method that employs a sucrose density gradient centrifugation step can minimize molecular damage. Based on this method, a recent publication describes how the density of the sucrose solution used during centrifugation was varied (30%, 50%, 72.5%) to find the most suitable concentration to extract glycogen particles of a wide variety of sizes, limiting the loss of smaller particles. A 10 min boiling step was introduced to test its ability to denature glycogen degrading enzymes, thus preserving glycogen. The lowest sucrose concentration (30%) and the addition of the boiling step were shown to extract the most representative samples of glycogen.

An optimal sucrose concentration was determined for the extraction of liver glycogen using sucrose density gradient centrifugation. The addition of a 10 min boiling step to inhibit glycogen-degrading enzymes proved beneficial.

Liver glycogen is a hyperbranched glucose polymer that is involved in the maintenance of blood sugar levels in animals. The properties of glycogen are ...

Extraction and Purification of FAHD1 Protein from Swine Kidney and Mouse Liver

Fumarylacetoacetate hydrolase domain-containing protein 1 (FAHD1) is the first identified member of the FAH superfamily in eukaryotes, acting as oxaloacetate decarboxylase in mitochondria. This article presents a series of methods for the extraction and purification of FAHD1 from swine kidney and mouse liver. Covered methods are ionic exchange chromatography with fast protein liquid chromatography (FPLC), preparative and analytical gel filtration with FPLC, and proteomic approaches. After total protein extraction, ammonium sulfate precipitation and ionic exchange chromatography were explored, and FAHD1 was extracted via a sequential strategy using ionic exchange and size-exclusion chromatography. This representative approach may be adapted to other proteins of interest (expressed at significant levels) and modified for other tissues. Purified protein from tissue may support the development of high-quality antibodies, and/or potent and specific pharmacological inhibitors.

This protocol describes how to extract fumarylacetoacetate hydrolase domain-containing protein 1 (FAHD1) from swine kidney and mouse liver. The listed methods may be adapted to other proteins of interest and modified for other tissues.

Fumarylacetoacetate hydrolase domain-containing protein 1 (FAHD1) is the first identified member of the FAH superfamily in eukaryotes, acting as ...

Routine Collection of High-Resolution cryo-EM Datasets Using 200 KV Transmission Electron Microscope

Cryo-electron microscopy (cryo-EM) has been established as a routine method for protein structure determination during the past decade, taking an ever-increasing share of published structural data. Recent advances in TEM technology and automation have boosted both the speed of data collection and quality of acquired images while simultaneously decreasing the required level of expertise for obtaining cryo-EM maps at sub-3 &#197; resolutions. While most of such high-resolution structures have been obtained using state-of-the-art 300 kV cryo-TEM systems, high-resolution structures can be also obtained with 200 kV cryo-TEM systems, especially when equipped with an energy filter. Additionally, automation of microscope alignments and data collection with real-time image quality assessment reduces system complexity and assures optimal microscope settings, resulting in increased yield of high-quality images and overall throughput of data collection. This protocol demonstrates the implementation of recent technological advances and automation features on a 200 kV cryo-transmission electron microscope and shows how to collect data for the reconstruction of 3D maps that are sufficient for de novo atomic model building. We focus on best practices, critical variables, and common issues that must be considered to enable the routine collection of such high-resolution cryo-EM datasets. Particularly the following essential topics are reviewed in detail: i) automation of microscope alignments, ii) selection of suitable areas for data acquisition, iii) optimal optical parameters for high-quality, high-throughput data collection, iv) energy filter tuning for zero-loss imaging, and v) data management and quality assessment. Application of the best practices and improvement of achievable resolution using an energy filter will be demonstrated on the example of apo-ferritin that was reconstructed to 1.6 &#197;, and Thermoplasma acidophilum 20S proteasome reconstructed to 2.1-&#197; resolution using a 200 kV TEM equipped with an energy filter and a direct electron detector.

High-resolution cryo-EM maps of macromolecules can be also achieved by using 200 kV TEM microscopes. This protocol shows the best practices for setting accurate optics alignments, data acquisition schemes, and selection of imaging areas that are all essential for the successful collection of high-resolution datasets using a 200 kV TEM.

Cryo-electron microscopy (cryo-EM) has been established as a routine method for protein structure determination during the past decade, taking an ...

A Nanobar-Supported Lipid Bilayer System for the Study of Membrane Curvature Sensing Proteins in vitro

Membrane curvature plays important roles&#160;in various essential processes of cells, such as cell migration, cell division, and vesicle trafficking. It is not only passively generated by cellular activities, but also actively regulates protein interactions and is involved in many intracellular signaling. Thus, it is of great value to examine the role of membrane curvature in regulating the distribution and dynamics of proteins and lipids. Recently, many techniques have been developed to study the relationship between the curved membrane and protein in vitro. Compared to traditional techniques, the newly developed nanobar-supported lipid bilayer (SLB) offers both high-throughput and better accuracy in membrane curvature generation by forming a continuous lipid bilayer on patterned arrays of nanobars with a pre-defined membrane curvature and local flat control. Both the lipid fluidity and protein sensitivity to curved membranes can be quantitatively characterized using fluorescence microscopy imaging. Here, a detailed procedure on how to form a SLB on fabricated glass surfaces containing nanobar arrays&#160;and the characterization of curvature-sensitive proteins on such SLB are introduced. In addition, protocols for nanochip reusing and image processing are covered. Beyond the nanobar-SLB, this protocol is readily applicable to all types of nanostructured glass chips for curvature sensing studies.

A Nanobar-Supported Lipid Bilayer System for the Study of Membrane Curvature Sensing Proteins in vitro

Here, a nanobar-supported lipid bilayer system is developed to provide a synthetic membrane with a defined curvature that enables the characterization of proteins with curvature sensing ability in vitro.

Membrane curvature plays important roles&#160;in various essential processes of cells, such as cell migration, cell division, and vesicle trafficking. It ...