<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article  PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="research article"><front><journal-meta><journal-id journal-id-type="publisher-id">OALibJ</journal-id><journal-title-group><journal-title>Open Access Library Journal</journal-title></journal-title-group><issn pub-type="epub">2333-9705</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/oalib.1105771</article-id><article-id pub-id-type="publisher-id">OALibJ-96587</article-id><article-categories><subj-group subj-group-type="heading"><subject>Articles</subject></subj-group><subj-group subj-group-type="Discipline-v2"><subject>Biomedical&amp;Life Sciences</subject><subject> Business&amp;Economics</subject><subject> Chemistry&amp;Materials Science</subject><subject> Computer Science&amp;Communications</subject><subject> Earth&amp;Environmental Sciences</subject><subject> Engineering</subject><subject> Medicine&amp;Healthcare</subject><subject> Physics&amp;Mathematics</subject><subject> Social Sciences&amp;Humanities</subject></subj-group></article-categories><title-group><article-title>
 
 
  Determination of Theobromine and Caffeine in &lt;i&gt;Theobroma cacao&lt;/i&gt; Husk from Ethanolic Extract by GC-MS after CC Separation
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>José</surname><given-names>González</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Max</surname><given-names>Monan</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Julio</surname><given-names>Perez</given-names></name><xref ref-type="aff" rid="aff3"><sup>3</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Enrique</surname><given-names>Gómez</given-names></name><xref ref-type="aff" rid="aff4"><sup>4</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Damaris</surname><given-names>De La C. Salgado</given-names></name><xref ref-type="aff" rid="aff4"><sup>4</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Danae</surname><given-names>Pérez</given-names></name><xref ref-type="aff" rid="aff4"><sup>4</sup></xref></contrib></contrib-group><aff id="aff1"><addr-line>Faculty of Technical Sciences, University of Pedagogical Sciences, Havana, Cuba</addr-line></aff><aff id="aff2"><addr-line>ARVARNAM, Martinica, France</addr-line></aff><aff id="aff4"><addr-line>Institute of Pharmacy and Foods, Havana University, Havana, Cuba</addr-line></aff><aff id="aff3"><addr-line>National Center of Toxicology, Military Hospital “Dr. Carlos J. Finlay”, Havana, Cuba</addr-line></aff><pub-date pub-type="epub"><day>05</day><month>11</month><year>2019</year></pub-date><volume>06</volume><issue>11</issue><fpage>1</fpage><lpage>9</lpage><history><date date-type="received"><day>9,</day>	<month>September</month>	<year>2019</year></date><date date-type="rev-recd"><day>23,</day>	<month>November</month>	<year>2019</year>	</date><date date-type="accepted"><day>26,</day>	<month>November</month>	<year>2019</year></date></history><permissions><copyright-statement>&#169; Copyright  2014 by authors and Scientific Research Publishing Inc. </copyright-statement><copyright-year>2014</copyright-year><license><license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p></license></permissions><abstract><p>
 
 
  After CC separation of 21 samples from Theobroma cacao Husk was analyzed by GC-MS, from ethanolic extract at 90% was recovered a solid residue of 1 g after several days on the table of the Lab. This main residue (300 mg) was analyzed after successive separations with mixtures of CHCl3: MeOH (7:3) and CHCl3: MeOH (5:5) in CC using S&#237;lica Gel G 60-120 Mesh. All samples were analyzed by TLC on silica gel with fluorescent indicator 254 nm on aluminum cards (layer thickness 0.2 mm) (10 &#215; 20 cm) using CHCl3: MeOH: n-propanol: water (5:6:1:4) as eluent (v/v/v). The presence of Caffeine (CF) and Theobromine (TB) was confirmed after several analyses of the samples by their characteristic fragmentation pattern but nevertheless was found the presence of Theophylline.
 
</p></abstract><kwd-group><kwd>&lt;i&gt;Theobroma cacao&lt;/i&gt;</kwd><kwd> Caffeine</kwd><kwd> Theobromine</kwd><kwd> GC-MS</kwd><kwd> CC</kwd><kwd> TLC</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>1. Introduction</title><p>Total production of cacao bean is estimated worldwide to be approximately 4.0 million tons in 2013, with a value about $12 billion. Residues or wastes from the cacao processing industry consist of cacao pod shell, husk, pulp/mucilage, and hull, which account for a high proportion, approximately 85% by fresh weight of total cacao pod mass, in which the annual worldwide amount of cacao pod husk is estimated to be about 55 million tons, which is equal to 13 times the total amount of cacao bean. Therefore, cacao pod husk needs to be exploited to produce high-value-added products and this waste has been considered as an abundant, inexpensive, and renewable source of caffeine and theobromine, which exhibits stimulatory effects on the central nervous, gastrointestinal, cardiovascular, renal, and respiratory systems [<xref ref-type="bibr" rid="scirp.96587-ref1">1</xref>] .</p><p>Native to lowland rainforests of the Amazon and Orinoco river basins, cacao is grown commercially in the New World tropics as well as western Africa and tropical Asia. Its seeds, called cocoa beans, are processed into cocoa powder, cocoa butter, and chocolate [<xref ref-type="bibr" rid="scirp.96587-ref2">2</xref>] .</p><p>Residues or wastes from the cacao processing industry consist of cacao pod shell, husk, pulp/mucilage, and hull, which account for a high proportion, approximately 85% by fresh weight of total cacao pod mass, in which the annual worldwide amount of cacao pod husk is estimated to be about 55 million tons, which is equal to 13 times the total amount of cacao bean [<xref ref-type="bibr" rid="scirp.96587-ref3">3</xref>] .</p><p>The consumption of cocoa/chocolate 1) increases plasma antioxidant capacity, 2) diminishes platelet function and inflammation, and 3) decreases diastolic and systolic arterial pressures. Data currently available indicate that daily consumption of cocoa-rich chocolate (rich in polyphenols) may at least partially lower cardiovascular disease risk. Further studies are required in order to establish the bioavailability and mechanisms of action of bioactive compounds in chocolate [<xref ref-type="bibr" rid="scirp.96587-ref4">4</xref>] .</p><p>Methylxanthines, theobromine and caffeine are used as analgesics, diet aids, and cold/flu remedies in numerous popular carbonated drinks. They are also the main compounds found in tea, coffee, sodas, chocolate, and various energy drinks. More than 120,000 tons of caffeine is consumed worldwide annually [<xref ref-type="bibr" rid="scirp.96587-ref5">5</xref>] .</p><p>The analysis of theobromine and caffeine in foods, biological fluids, environmental samples, plants, and water, was provided with different instrumental methods, such as high-performance liquid chromatography (HPLC) [<xref ref-type="bibr" rid="scirp.96587-ref6">6</xref>] , gas chromatography-mass spectrometry-flame ionization detection (GC-MS-FID) [<xref ref-type="bibr" rid="scirp.96587-ref7">7</xref>] , Fourier transform-infrared spectrophotometry (FT-IR) [<xref ref-type="bibr" rid="scirp.96587-ref8">8</xref>] , near-infrared spectroscopy [<xref ref-type="bibr" rid="scirp.96587-ref9">9</xref>] , UV-Vis spectrophotometry [<xref ref-type="bibr" rid="scirp.96587-ref10">10</xref>] , FT-Raman spectrometry [<xref ref-type="bibr" rid="scirp.96587-ref11">11</xref>] , and capillary electrophoresis (CE) [<xref ref-type="bibr" rid="scirp.96587-ref12">12</xref>] .</p><p>The aim of this research was to determine the presence of theobromine, caffeine and theophylline in a solid sample from ethanolic extracts at 90% from Theobroma cacao husk after carried out the insoluble solid by CC and running by CG-MS the 21 samples recovered after CC elution.</p></sec><sec id="s2"><title>2. Materials and Methods</title><sec id="s2_1"><title>2.1. Sample Collection and Processing:</title><p>The sample was the husk of cocoa bean after its separation from the fruits. It was supplied in 2018 by the Chocolate Factory located in Baracoa, Guant&#225;namo Province, Cuba. After the collection the husks were packet in nylon bags without elimination of foreign matters. The material was grounded in a high-speed hammer mill. The sample keeps its brown color (<xref ref-type="fig" rid="fig1">Figure 1</xref>) and a very nice chocolate’s smell.</p></sec><sec id="s2_2"><title>2.2. Extract Preparation</title><p>The extracts were prepared with the ground material (60 g) without screen extracted in a Soxhlet apparatus with 675 mL of ethanol at 90% for 20 hours. The ethanolic extracts were concentrated and evaporated under vacuum to 200 mL at 120 rpm, a temperature of 70˚C and 500 mbar.</p></sec><sec id="s2_3"><title>2.3. CC Separation of the Samples</title><p>After extraction the ethanolic extract was kept on the Lab table during few days. A solid yellowish-green residue (1 g) appeared on the bottom of the recipient and was recovered by decantation (<xref ref-type="fig" rid="fig2">Figure 2</xref>).</p><p>300 mg of this solid was then passed thought a CC (31.5 cm &#215; 1.5 cm ϕ) (<xref ref-type="fig" rid="fig3">Figure 3</xref>) using as stationary phase S&#237;lica Gel G 60 - 120 Mesh (Merck) and as mobile phase 25 mL of a mixture of CHCl<sub>3</sub>: MeOH (7:3). After that point, was added successively, 20 mL of pure MeOH, 30 mL of CHCl<sub>3</sub>: MeOH (7:3); 10 mL of MeOH and finally, 20 ML of CHCl<sub>3</sub>: MeOH (5:5). The column was cleaned first with chloroform.</p></sec><sec id="s2_4"><title>2.4. Procedures, Instrumentation and Parameters</title><p>The samples were subjected to chromatographic analysis in equipment GC/MS; brand Shimadzu QP2010, equipped with a splitter split/splitless. With a BP5 (30 m &#215; 0.25 mm &#215; 0.25 microns) capillary column under the following chromatographic conditions: Helium gas carrier obtained by electron impact fragments to a power of 70 eV rate of 1.2 mL/min, 1:50 split flow and the volume of injected sample of 1 μL. Programmed oven temperature: initial temperature was 70˚C with a heating ramp of 10˚C/min to 300˚C and remained stable at this temperature for 10 minutes. Subsequently the temperature was increased at a rate of 10˚C/minute to 300˚C for a total time of 78 minutes with an injector temperature 250˚C and the interface temperature 300˚C. The compounds were analyzed using GC/MS NIST21 and NIST107 library and having into account the results obtained after phytochemical screening according with Gonz&#225;lez et al., 2017. Silylation agent was N,O-bis(trimethylsilyl) trifluoroacetamide (BSTFA), CAS 25561-30-2, Lot: 0901-1 Macherey-Nagel GmbH &amp; C. KG.</p></sec></sec><sec id="s3"><title>3. Results and Discussion</title><p>Twenty-one samples were recovered from the CC after solid insoluble sample separation (<xref ref-type="fig" rid="fig4">Figure 4</xref>). Five fractions (1 - 5) were obtained using a mixture of CHCl<sub>3</sub>: MeOH (7:3). Successively were added pure MeOH (A-D), alternating with CHCl<sub>3</sub>: MeOH (7:3) (6 - 11), MeOH (E-F) and CHCl<sub>3</sub>: MeOH (5:5) (12 - 15). In general, were taken 21 samples of 5 mL; 15 of them from the mixture of CHCl<sub>3</sub>: MeOH and six from pure MeOH.</p><p>The twenty-one samples after running by CG-MS showed a general chromatogram as shown in <xref ref-type="fig" rid="fig5">Figure 5</xref>. The most prominent peaks are between 25 and 40 minutes of retention time with some few exceptions.</p><p>The automatically comparison of the results with NIST 21 and NIST 107 Libraries allow us to tentatively suggest the presence of caffeine and theobromine in all samples but with different retention times like is presented in <xref ref-type="table" rid="table1">Table 1</xref>. In all cases caffeine appear firstly than theobromine. The first Methylxanthine was</p><table-wrap id="table1" ><label><xref ref-type="table" rid="table1">Table 1</xref></label><caption><title> Retention times of caffeine and theobromine in each sample</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Sample</th><th align="center" valign="middle" >Caffeine</th><th align="center" valign="middle" >Theobromine</th><th align="center" valign="middle" >Manually predominant compound</th></tr></thead><tr><td align="center" valign="middle" >1</td><td align="center" valign="middle" >29.490</td><td align="center" valign="middle" >29.695</td><td align="center" valign="middle" >Caffeine</td></tr><tr><td align="center" valign="middle" >2</td><td align="center" valign="middle" >29.245</td><td align="center" valign="middle" >29.695</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >3</td><td align="center" valign="middle" >29.235</td><td align="center" valign="middle" >29.865</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >4</td><td align="center" valign="middle" >29.230</td><td align="center" valign="middle" >29.820</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >5</td><td align="center" valign="middle" >29.270</td><td align="center" valign="middle" >29.665</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >6</td><td align="center" valign="middle" >29.265</td><td align="center" valign="middle" >29.695</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >7</td><td align="center" valign="middle" >29.250</td><td align="center" valign="middle" >29.705</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >8</td><td align="center" valign="middle" >29.260</td><td align="center" valign="middle" >29.690</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >9</td><td align="center" valign="middle" >29.260</td><td align="center" valign="middle" >29.880</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >10</td><td align="center" valign="middle" >29.255</td><td align="center" valign="middle" >29.710</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >11</td><td align="center" valign="middle" >29.260</td><td align="center" valign="middle" >29.840</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >12</td><td align="center" valign="middle" >28.250</td><td align="center" valign="middle" >29.890</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >13</td><td align="center" valign="middle" >29.250</td><td align="center" valign="middle" >30.005</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >14</td><td align="center" valign="middle" >29.240</td><td align="center" valign="middle" >29.905</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >15</td><td align="center" valign="middle" >29.235</td><td align="center" valign="middle" >29.800</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >A</td><td align="center" valign="middle" >29.260</td><td align="center" valign="middle" >29.775</td><td align="center" valign="middle" >Uncertain</td></tr><tr><td align="center" valign="middle" >B</td><td align="center" valign="middle" >29.265</td><td align="center" valign="middle" >29.610</td><td align="center" valign="middle" >Uncertain</td></tr><tr><td align="center" valign="middle" >C</td><td align="center" valign="middle" >29.240</td><td align="center" valign="middle" >29.750</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >D</td><td align="center" valign="middle" >29.245</td><td align="center" valign="middle" >29.710</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >E</td><td align="center" valign="middle" >29.260</td><td align="center" valign="middle" >29.625</td><td align="center" valign="middle" >Theobromine</td></tr><tr><td align="center" valign="middle" >F</td><td align="center" valign="middle" >29.245</td><td align="center" valign="middle" >29.915</td><td align="center" valign="middle" >Theobromine</td></tr></tbody></table></table-wrap><p>between 29.230 min and 29.270 min of retention time, while the second one was between 29.610 and 30.005 min of retention time.</p><p>Manually registration of each compound showed a big difference, because using this kind of selective search each sample had another behavior. Sample 1 showed the presence of caffeine at 29.485 minutes of retention time, according to NIST 107 Library with a coincidence of 91% - 93%, while in sample 2 the coincidence was only 65% according to NIST 21 Library to theobromine as a predominant compound.</p><p>No theophylline was detected in this research. According to V&#225;zquez-Ovando in 2016 [<xref ref-type="bibr" rid="scirp.96587-ref13">13</xref>] , the main alkaloid in cacao is theobromine, but both compounds can coexist because of the presence of the theobromine sintase enzyme. Accumulation of purine alkaloids is dependent on the presence of substrate specificity of N-metil-transferase.</p><p>Using LC?ESI?MS, according to [<xref ref-type="bibr" rid="scirp.96587-ref5">5</xref>] , the researchers found that both compound (caffeine and theobromine) had the same fragmentation pattern in the peak m/z 137. As discussed in [<xref ref-type="bibr" rid="scirp.96587-ref14">14</xref>] , using different extraction methods and HPLC, reported that both alkaloids had the same fragmentation pattern and declare that is possible to find out the superposition of theobromine, theophylline and caffeine as a mixture.</p><p><xref ref-type="fig" rid="fig6">Figure 6</xref> shows the fragmentation pattern of both chemical components and the fragmentation pattern of caffeine according to [<xref ref-type="bibr" rid="scirp.96587-ref15">15</xref>] and the data from our research group in this investigation.</p></sec><sec id="s4"><title>4. Conclusion</title><p>This study was an exploratory and valuable assessment for further studies. The findings from this study indicated that cacao pod husk had high contents of caffeine and theobromine, but low or none contents of theophylline. Therefore, the use of these extraction and purification conditions for effective exploitation of theobromine and caffeine from cacao pod husk is a promising and sustainable trend. In further studies, it is necessary to determine the biological variability of theobromine and caffeine in cacao pod husk samples, as well as produce theobromine-caffeine enriched powder and evaluate its biological activity in various models for potential application in the medical, nutraceutical and pharmaceutical industries.</p></sec><sec id="s5"><title>Conflicts of Interest</title><p>The authors declare no conflict of interest.</p></sec><sec id="s6"><title>Cite this paper</title><p>Gonz&#225;lez, J., Monan, M., Perez, J., G&#243;mez, E., De La C. Salgado, D. and P&#233;rez, D. (2019) Determination of Theobromine and Caffeine in Theobroma cacao Husk from Ethanolic Extract by GC-MS after CC Separation. 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