Citrus lemon essential oil: chemical composition, antioxidant and antimicrobial activities with its preservative effect against Listeria monocytogenes inoculated in minced beef meat

Abstract

BackgroundLemon (Citrus limon) is a flowing plant belonging to the Rutaceae family. Citrus plants constitute one of the main valuable sources of essential oil used in foods and medicinal purposes.MethodsIn this study, we assessed chemical composition, antioxidant and antimicrobial activities of C. limon essential oil (ClEO) with its preservative effect against Listeria monocytogenes inoculated in minced beef meat. Gas chromatography/mass spectrometry (GC-MS) was used to identify the major components of the obtained ClEO. The antioxidant activities of this ClEO were determined according to the β-carotene bleaching assay, as well as by 2.2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. For antimicrobial activity, agar well diffusion method was used and the minimum inhibitory concentrations (MICs) as well as the minimum fungicidal concentrations (MFCs) were determined. The in situ effect of the ClEO was evaluated through physicochemical parameters (pH and thiobarbituric acid reactive substances (TBARS), as well as against L. monocytogenes in minced beef meat model.ResultsTwenty one components were identified in the ClEO and the two dominant compounds were limonene (39.74%) and β-Pinene (25.44%). This ClEO displayed an excellent DPPH scavenging ability with an extract concentration providing 50% inhibition (IC50) of 15.056 μg/ml and a strong β-carotene bleaching inhibition after 120 min of incubation with an IC50 of 40.147 μg/ml. The MICs varied from 0.039 to 1.25 mg/ml for Gram positive bacteria and from 0.25 to 2.5 mg/ml for Gram-negative bacteria. The meat preserving potential of ClEO was investigated against L. monocytogenes. ClEO successfully inhibited development of L. monocytogenes in minced beef meat. The application of ClEO at a 0.06 and 0.312 mg/g, may open new promising opportunities for the prevention of contamination from and growth of pathogenic bacteria, particularly L. monocytogenes, during minced beef meat storage at 4 °C. Additionally, during storage period, physicochemical values (pH and TBARS) were higher in control meat than treated meat with ClEO suggesting an efficient antioxidant activity of ClEO.ConclusionIt was suggested that the ClEO may be a new potential source as natural antimicrobial and antioxidant agents applied in food systems and pharmaceutical industry.

Biological activities of the essential oil from the Moro orange peel (Citrus sinensis (L.) Osbeck)

“…A total of four terpene components were identified in the essential oil: α‐pinene, sabinene, myrcene, and limonene. These results confirm the presence of limonene as the principal component of the essential oils from different types of citrus peels …”

“…These results confirm the presence of limonene as the principal component of the essential oils from different types of citrus peels. [15][16][17] Gomes et al 14…”

Essential Oils with High Activity against Stationary Phase Bartonella henselae

“…Citrus plants constitute one of the most valuable and important sources of essential oil served in food processing and medical use. Citrus limonum essential oil was reported to have antimicrobial activities with preservative effect against Listeria monocytogenes inoculated in minced beef meat [28], and remarkable miticidal activity in vitro and in vivo applications against sarcoptic mange in rabbits [29]. Besides, the essential oil from Citrus limetta Risso peels could alleviate skin inflammation, both tested in vitro and in vivo [30], while the essential oil from Citrus aurantium L. var.…”

The Case for a Lemon Bioeconomy

“…Applying and expanding the latter in vitro findings, in 2017 a team in Tunisia reported that lemon EO added to minced beef meat successfully inhibits development of L. monocytogenes in meat treated with EO at a concentration between 0.06 and 0.312 mg of EO per g of meat ( Figure ), reducing the growth of the bacteria by 2.5 log cycles after 4 and 6 days of storage at 4 °C, respectively, thereby opening “new promising opportunities for the prevention of contamination from and growth of pathogenic bacteria… during minced beef meat storage at 4 °C.” [ 25 ]…”

“…Reproduced under the terms of the Creative Commons Attribution 4.0 International License. [ 25 ] Copyright 2017, The Authors.…”