Journal of the Brazilian Chemical Society
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13322
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Item Chemometric analysis of UV characteristic profile and infrared fingerprint variations of Coffea arabica green beans under different space management treatments(Sociedade Brasileira de Química, 2016) Terrile, Amélia E.; Marcheafave, Gustavo G.; Oliveira, Guilherme S.; Rakocevic, Miroslava; Bruns, Roy E.; Scarminio, Ieda S.Ultraviolet characteristic profiles and infrared spectroscopic (FTIR) fingerprints of green bean extracts of Coffea arabica L., cv. IAPAR 59, cultivated in two planting patterns, rectangular and square, and at two different densities, 10,000 and 6,000 plants ha-1, identified as R10,R6,S10, and S6 were analyzed with principal component and hierarchical cluster analyses. A simplex centroid design for four solvents (ethanol, acetone, dichloromethane, hexane) was used for sample extraction. The largest chlorogenic acid (CGA) contents were found at the lower planting density. The dichloromethane extracts of the S10 treatment showed the highest levels of unsaponifiable lipids (cafestol and kahweol). The R6 treatment showed a slightly higher content of cafestol and kahweol. Cluster analysis of FTIR fingerprints confirmed that the CGA and caffeine levels differentiate the spatial arrangements. The FTIR fingerprints suggest that green beans from S6 and R10 were richer in lipids and the other two treatments had more sugars and proteins.Item Solubility and bioaccessibility of Ba, Ca, Cr, Cu, Fe, Mg, Mn, P, Sr and Zn in slim coffee infusions by in vitro gastrointestinal digestion(Sociedade Brasileira de Química, 2015) Szymczycha-Madeja, Anna; Welna, Maja; Pohl, PawelSolubility and bioaccessibility of Ba, Ca, Cr, Cu, Fe, Mg, Mn, P, Sr and Zn in slim coffees were investigated using an in vitro method. Two different compositions of solutions simulating gastric and intestinal juices were tested: SGJ1 + SIJ1 (0.02% pepsin in 0.10 mol L-1 HCl; 0.015% pancreatin with 0.15% bile salts in 0.10 mol L-1 NaHCO3) and SGJ2 + SIJ2 (0.32% pepsin with 0.20% NaCl in 0.08 mol L-1 HCl; 0.40% pancreatin with 2.5% bile salts in 0.10 mol L-1 NaHCO3). Soluble and bioaccessible fractions (in %) in reference to total concentrations of studied elements in infusions were as follows: Ba (81.2, 34.2), Ca (84.4, 44.5), Cr (80.1, 44.8), Cu (69.2, 24.1), Fe (72.5, 6.6), Mg (89.5, 69.6), Mn (44.3, 28.4), P (96.6, 84.6), Sr (85.9, 46.8), Zn (80.8, 59.5). These results suggest that slim coffees are not a rich source of minerals.Item Application of carbon composite adsorbents prepared from coffee waste and clay for the removal of reactive dyes from aqueous solutions(Sociedade Brasileira de Química, 2015) Santos, Davis C. dos; Adebayo, Matthew A.; Lima, Eder C.; Pereira, Simone F. P.; Cataluña, Renato; Sauier, Caroline; Thue, Pascal S.; Machado, Fernando M.A novel carbon composite was prepared from a mixture of coffee waste and clay with inorganic:organic ratio of 1.3 (CC-1.3). The mixture was pyrolysed at 700 °C. Considering the application of this adsorbent for removal of anionic dyes, the CC-1.3 was treated with a 6 mol L−1 HCl for 24 h to obtain ACC-1.3. Fourier transform infrared (FTIR), N2 adsorption/desorption curves, scanning electron microscope (SEM) and powder X-ray diffractometry (XRD) were used for characterisation of CC-1.3 and ACC-1.3 carbon adsorbents. The adsorbents were effectively utilised for removal of reactive blue 19 (RB-19) and reactive violet 5 (RV-5) textile dyes from aqueous solutions. The maximum amounts of RB-19 dye adsorbed at 25 °C are 63.59 (CC-1.3) and 110.6 mg g−1 (ACC-1.3), and 54.34 (CC-1.3) and 94.32 mg g−1 (ACC-1.3) for RV-5 dye. Four simulated dye-house effluents were used to test the application of the adsorbents for treatment of effluents.Item Evaluation of the bioaccessability of Ca, Fe, Mg and Mn in ground coffee infusions by in vitro gastrointestinal digestion(Sociedade Brasileira de Química, 2014) Stelmach, Ewelina; Pohl, Pawel; Szymczycha-Madeja, AnnaThe bioaccessibility of Ca, Mg, Mn and Fe in ground coffee brews was assessed through in vitro gastrointestinal digestion with stomach and intestinal juice solutions (pepsin, pancreatin and bile salts). Absorption of metals in the intestinal villi was simulated by ultrafiltration over a 3 kDa molecular weight cut-off semi-permeable membrane. Concentrations of Ca, Fe, Mg and Mn in coffee infusions and permeates of gastrointestinal incubates were measured by flame atomic absorption spectrometry. It was established that Mg, with a 62% contribution to the bioaccessible fraction, was the most bioaccessible. The bioaccessibilities of Ca (42%) and Fe (43%) were similar but individual results for both metals varied widely. The least bioaccessible metal was Mn, with an average contribution of 27%. Drinking one cup of coffee daily covers dietary reference intakes of Ca, Fe, Mg and Mn to a small degree (less than 3%).Item Spectroscopic and chromatographic fingerprint analysis of composition variations in Coffea arabica leaves subject to different light conditions and plant phenophases(Sociedade Brasileira de Química, 2014) Delaroza, Fernanda; Rakocevic, Miroslava; Malta, Galileu Bernardes; Bruns, Roy Edward; Scarminio, Ieda SpacinoFingerprints of self-shaded and sunlight-exposed leaves of the same Coffea arabica plant were obtained to determine metabolic concentration changes owing to different light environments and phenological stages. Leaf extract yields of the ethanol, acetone, dichloromethane and hexane solvents, as well as their statistical design mixtures, are reported. Highest yields are obtained with binary 1:1 ethanol-acetone mixtures for all sun-exposed and self-shaded leaves. Principal component analysis (PCA) of Fourier transform infrared (FTIR) spectra of leaf extracts indicate spectral differences between 2962-2828, 1759-1543 and below 1543 cm-1 that can be attributed to higher concentrations of fatty acid esters or the ester group in triglycerides, caffeine, chlorogenic acids and carbohydrates that are more prevalent in leaves of flowering plants. Highperformance liquid chromatography with UV diode array detector (HPLC-UV-DAD) spectra of the chromatographic peaks for the extracts showed that sun-exposed samples contain stronger absorptions for caffeine, chlorogenic acid and theobromine. Confirmatory experiments carried out with reference UV calibration curves determined caffeine contents for sun-exposed leaves that are about double those for self-shaded leaves of flowering plants. Knowledge of leaf caffeine content in Coffea arabica is of ecological importance since sun-exposed conditions seem more stressful than self-shading ones for this species. Lipid concentrations in self-shaded leaves are almost double those that were sun-exposed.Item Ambient mass spectrometry employed for direct analysis of intact arabica coffee beans(Sociedade Brasileira de Química, 2014) Garrett, Rafael; Schwab, Nicolas V.; Cabral, Elaine C.; Henrique, Brenno V. M.; Ifa, Demian R.; Eberlin, Marcos N.; Rezende, Claudia M.The ambient ionization mass spectrometry techniques: desorption electrospray ionization (DESI) and easy ambient sonic-spray ionization (EASI) were explored as fast and simple ways to directly analyze the surface of intact green Arabica coffee beans treated by the dry, semi-dry and wet post-harvest methods. Five compounds were identified, including three components of the waxy layer that covers the green coffee beans (β N-arachinoyl-5-hydroxytryptamide, β N-behenoyl5-hydroxytryptamide, and β N-lignoceroyl-5-hydroxytryptamide) and that are commonly related to related to stomach irritations caused by coffee beverage consumption in sensitive people. Moreover, the multivariate statistical tool principal component analysis (PCA) was employed to differentiate the coffee post-harvest methods using data from the mass spectrometry fingerprinting analyses. Extraction procedures or sample pretreatment steps were not required for DESI and EASI analyses and the results obtained suggest therefore that these techniques could be used for rapid quality control and certification processes of coffees samples.Item Comparison of extraction methods for kahweol and cafestol analysis in roasted coffee(Sociedade Brasileira de Química, 2013) Dias, Rafael C. E.; Faria, Adelia F. de; Mercadante, Adriana Z.; Bragagnolo, Neura; Benassi, Marta de T.Kahweol and cafestol, diterpenes from the unsaponifiable fraction of coffee, present known effects on human health such as anticarcinogenic and hipercholesterolemic activities. There are discrepancies regarding the levels reported for these compounds in roasted coffee, probably due to the extraction processes. Therefore, four sample preparation methods were studied: direct hot saponification (DHS), direct cold saponification (DCS); and Bligh and Dyer (BD) or Soxhlet (SO) extraction followed by saponification. The levels of diterpenes and their dehydro derivatives obtained by high performance liquid chromatography with diode array and mass spectrometry detectors (HPLC-DAD-MS/MS) and the chromatographic profiles of roasted coffee, obtained by these four methods, were compared. DHS was more efficient for extraction, showing better separation of chromatographic peaks and levels of 930.2 (± 36.8), 113.2 (± 4.7), 568.6 (± 16.6) and 87.1 (± 3.7) mg 100 g–1 for kahweol, dehydrokahweol, cafestol and dehydrocafestol, respectively. The DHS extract presented a diterpene content (kahweol and cafestol) 15% superior to that of DCS and up to 88% superior than using SO and BD methods.Item Discrimination of commercial roasted and ground coffees according to chemical composition(Sociedade Brasileira de Química, 2012) Souza, Romilaine M. N. de; Benassi, Marta T.Roasted and ground 38 commercial coffees and coffees of known species (arabica, robusta) were characterized by principal component analysis using as variables nicotinic acid, trigonelline, 5-o-caffeoylquinic acid (5-CQA), caffeine, kahweol and cafestol, which are potentially indicative of species. The objective of the study was to assess the relevance of such parameters in coffee discrimination. Nicotinic acid allowed the characterization of roasting degree. Trigonelline and 5-CQA presented variability among arabica and robusta coffees as well as among comercial ones. Thermostable parameters (caffeine, kahweol and cafestol) had high discriminative potential between the species. In general, high levels of caffeine and low levels of diterpenes (kahweol and cafestol) were related with higher proportions of robusta in the products, which were observed by the decreasing kahweol/cafestol ratio and increasing caffeine/kahweol ratio. The use of these new parameters (kahweol/cafestol and caffeine/kahweol ratios) was suggested as tools for assessing the addition of robusta in commercial coffees.Item Comparative study of metal contents in Brazilian coffees cultivated by conventional and organic agriculture applying principal component analysis(Sociedade Brasileira de Química, 2010) Santos, José S. dos; Santos, Maria Lúcia P. dos; Conti, Melina M.The aim of this study was to evaluate of availability of nutrients and toxic elements in green coffees produced in traditional, technological and transitional organic farms in Southwest BahiaBrazil. Levels of the nutrients minerals were determined directly in samples of soils and coffee tissues from four farms by flame atomic absorption spectrometry (FAAS) and toxic elements (Cr, Ni, Cd and Pb) by inductively coupled plasma optical emission spectrometry (ICP OES). The application of statistical methods (cluster and principal components analysis) revealed the importance of the conversion period to guarantee a product genuinely organic during the change to organic agriculture. On the other hand, the study of correlations between agricultural methods and metals concentrations in coffee suggested that Cd, Cu, Zn and other toxic elements contained in some inorganic fertilizers used in the traditional and technological coffee farms may cause na increase of toxic metals concentration in the crop soil, be taken up by plants, and passed on in the food chain.Item Green and roasted arabica coffees differentiated by ripeness, process and cup quality via electrospray ionization mass spectrometry fingerprinting(Sociedade Brasileira de Química, 2009) Amorim, Ana Carolina L.; Hovell, Ana Maria C.; Pinto, Angelo C.; Eberlin, Marcos N.; Arruda, Neusa P.; Pereira, Elenilda J.; Bizzo, Humberto R.; Catharino, Rodrigo R.; Morais Filho, Zenildo B.; Rezende, Claudia M.Direct infusion electrospray ionization mass spectrometry in both the negative ESI(-)-MS and positive ESI(+)-MS ion modes are investigated to differentiate green and roasted Arabica coffees with different stages of ripeness (green, ripe and overripe), post-harvesting process (dry, wet and semi-wet) and coffees with diferente cup qualities. In the ESI(-)-MS of green coffees, ions from deprotonated fatty acids and chlorogenic acids are the most important for ripeness discrimination. In the ESI(+)-MS, maturity is differentiated by ions from protonated caffeine, chlorogenic acids and K+ adducts of fatty acids. To differentiate between post-harvesting process in both ionization modes, ions from fatty acids, chlorogenic acids, sugars and carboxylic acids generated in the fermentation process are the most representative. Roasted Arabica coffees are also well discriminated: in the ESI(-)-MS, ions from chlorogenic acids and short-chain organic acids derived from sugars are important. In the ESI(+)-MS, discrimination are mainly performed by low m/z ions such as protonated pyridine and alkylpiridines formed via trigonelline degradation. Both ESI(+)-MS and ESI(-)-MS are able to differentiate cup quality for Arabica roasted coffees and the ions used to perform discrimination are the same ones described in ripeness and post-harvesting processes.