Journal of the Brazilian Chemical Society
URI permanente para esta coleção${dspace.url}/handle/123456789/13322
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Item Bioactive Diterpenes and Serotonin Amides in Cold-Pressed Green Coffee Oil (Coffea arabica L.)(Sociedade Brasileira de Química, 2024-02-09) Silva, Rodrigo M. V.; Brand, Ana Laura M.; Tinoco, Natalia A. B.; Freitas, Suely P.; Rezende, Claudia M.Cold pressing is an environment-friendly mechanical extraction for oils from seeds. In this work, cold-pressed green Arabica coffee oil was investigated related to the influence of the pressing variables (preheating, exit diameter, screw speed, and particle size) on the chemical oil composition, mainly on the diterpenes and, for the first time in the scientific literature, on the content of serotonin amides (N-alkanoyl-5-hydroxytryptamides (Cn-5HT)). The oil yield from screw pressing varied from 2.65 to 6.27%, with major yields obtained as the size of the particle and temperature increased. Soxhlet extraction produced 9.46 ± 0.04% of oil. The fatty acid content of the oils varied from 32.79 to 33.49% and showed no significant difference among the different pressing conditions. The amount of the diterpenes kahweol and cafestol ranged from 13.33 to 16.72 mg g-1 and 37.11 to 47.14 mg g 1 of oil, respectively, summing 50.44 to 63.86 mg g 1 of diterpenes. The total content of Cn-5HTs ranged from 307.92 to 1716.52 µg g 1, being 114.42 to 577.37 µg g 1 for arachidic acid-5-hydroxytryptamide, (C20-5HT) and 193.50 to 1068.08 µg g 1 for behenic acid-5-hydroxytryptamide (C22-5HT) in oil, the most abundant in coffee bean. From the 16 cold press treatments, six conditions showed significant amounts of these compounds. Aspects related to the biological activity and relevance of coffee lipid diterpenes and Cn-5HTs are discussed.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 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.