Chemical Composition and Antimicrobial Activity of the Essential Oils of Two Aromatic Plants Cultivated in Morocco (Cinnamomum cassia and Origanum compactum)

Asmae Chahbi,Hamid El Amri,Saâdiya Nassik,El Mestafa El Hadrami,El Haj El Maadoudi,Mohamed Boukharta,Ahmed Douaik

doi:10.1155/2020/1628710

Abstract

The present study aims to evaluate the antibacterial properties of natural products according to a pharmacodynamic approach in order to propose them as alternatives to synthetic products. Two essential oils (Cinnamomum cassia and Origanum compactum) were the subject of the chemical and biological study. First, we evaluated the sensitivity of the strains of avian Salmonella to the main antibiotics used and then to the chromatographic analysis of the composition of the two essential oils (EO); finally, we proceeded to the in vitro evaluation of the antibacterial activities of these EO (alone and in combination with antibiotics). The results obtained showed that carvacrol (35.2%), followed by γ-terpinene (20.1%), was the main constituent of the essential oil of O. compactum while cinnamaldehyde (69.1%) represents the major component of the essential oil of C. cassia. The antibioresistance profile of the Salmonella tested showed resistance to ampicillin (35%) and oxytetracycline (41.3%). Active products extracted from the essential oils studied showed antibacterial activity against Salmonella strains. C. cassia products were shown to be more active for Salmonella enteritidis (average inhibition diameter: 16.3 mm) and for Salmonella gallinarum (average inhibition diameter: 27.7 mm). The best synergistic activity with antibiotics has been obtained with the essential oil of C. cassia and its active product cinnamaldehyde. The minimum inhibitory concentration (MIC) of cinnamaldehyde is the lowest (0.05%). The results prove the presence of an antibacterial activity and a synergistic effect of two essential oils studied with the main antibiotics.

Highlights

Salmonellosis is the most common foodborne bacterial disease worldwide. e bacteria responsible belongs to the family of Enterobacteriaceae and the genus Salmonella and is a Gram negative, optional anaerobic, and most often mobile [1,2,3].Currently, there are approximately 2610 Salmonella serotypes determined by their O and H antigenic structures and classified according to the Kauffmann–White classification updated annually [4].Salmonella is a predominant cause of food infections
E misuse of antimicrobial agents has led to the emergence of resistant bacteria. is resistance to antibiotics represents a serious problem to human health [6]. e majority of antibiotic resistance is due to the genes that could be expressed in any bacteria. is notion is illustrated by the term “resistome” which defines the set of antibiotic resistance genes that can be found in environmental bacteria as well as in pathogenic bacteria [7]
Aromatic Plants. e aromatic plants C. cassia and O. compactum (Figures 1(a) and 1(b)) were collected in 2018, at the Rabat region. e samples obtained were kept at 4°C until the time of analysis. e extraction of essential oils from the samples was carried out at the laboratory of the Department of Food Sciences of the Agronomic and Veterinary Institute (IAV Hassan II). e reference cinnamaldehyde (Sigma-Aldrich, 99%) and carvacrol (SigmaAldrich, >98%) were provided by the same department

Summary

Introduction

Salmonellosis is the most common foodborne bacterial disease worldwide. e bacteria responsible belongs to the family of Enterobacteriaceae and the genus Salmonella and is a Gram negative, optional anaerobic, and most often mobile [1,2,3].Currently, there are approximately 2610 Salmonella serotypes determined by their O and H antigenic structures and classified according to the Kauffmann–White classification updated annually [4].Salmonella is a predominant cause of food infections. E results of the antibacterial activity of essential oils and majority compounds were studied on the reference strain (Table 3).

Results

Conclusion