Chemical characterisation by UPLC‐Q‐ToF‐MS/MS and antibacterial potential of Coffea arabica L. leaves: A coffee by‐product

Abstract

Introduction: Coffea arabica L. leaves are considered a by-product of the coffee industry however they are sources of several bioactive compounds.Objectives: This study aimed to evaluate the chemical composition and the in vitro antibacterial activity of the lyophilised ethanol extract of arabica coffee leaves (EE-CaL).Material And Methods: The chemical characterisation of EE-CaL was performed using ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q-ToF-MS/MS). The in vitro antibacterial effect of EE-CaL was evaluated using the broth microdilution method and the adapted drop plate agar method to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC), respectively. Results:The chemical analysis of EE-CaL revealed the presence of compounds from the alkaloid class, such as trigonelline and caffeine, in addition to the phenolic compounds such as quinic acid, 5-caffeoylquinic acid, caffeic acid-O-hexoside, mangiferin, (epi)catechin, (epi)catechin monoglucoside and procyanidin trimer.Regarding the antibacterial potential, EE-CaL was active against Gram-positive and Gram-negative bacteria, being more effective against Escherichia coli (ATCC 25922) (MIC = 2500 μg/mL and bactericidal effect). Conclusion:The results of this research suggest that coffee leaves, a by-product, possess compounds with antibacterial properties. Thus, further studies with coffee leaf extracts must be carried out to relate the compounds present in the extract with the antibacterial activity and find the mechanisms of action of this extract against bacteria.

LC-MS/MS-based chemical profiling of water extracts of Moringa oleifera leaves and pharmacokinetics of their major constituents in rat plasma

“…This compound generated a fragment ion [M + H-COOH] + at m/z 94.0652. By comparing the mass spectrum information reported in the literature, the compound was confirmed as trigonelline ( Gilmar et al, 2022 ; Tatiane et al, 2019 ).…”

Recent patent applications for coffee and coffee by‐products as active ingredients in cosmetics

“…The patent CA3067924A1 is a topical cream with a bactericidal component and various substances, such as green coffee bean extract, which revitalizes and restores the natural skin microbiota. Data from the literature widely report the antimicrobial potential of several compounds present in coffee, such as chlorogenic acids, caffeine, trigonelline, quinic acid, catechin, UM, melanoidins and mangiferin (described in coffee leaves) [29][30][31][32][33][34].…”

Delving into Agri-Food Waste Composition for Antibacterial Phytochemicals

“…The coffee industry generates a significant amount of by-products that can be used as a source of bioactive compounds [ 102 , 103 ]. Researchers have evaluated the antibacterial activity of arabica coffee leaves and found that the extracts contain the alkaloids trigonelline and caffeine [ 102 ]. These extracts were found to be effective against E. coli .…”