Optimizing the Method of Rosemary Essential Oils Extraction by Using Response Surface Methodology (RSM)-Characterization and Toxicological Assessment

Abstract

Rosemary (Rosmarinus officinalis L.) is a plant with needle-shaped leaves. It is mainly found in Mediterranean regions (Algeria, Morocco and Tunisia). Rosemary essential oil (EO) has several therapeutic virtues that were widely studied. However, the use of this EO is restricted due to its sensitivity to oxidation. Nanoencapsulation based on EO and polymers has been developed as one of the promising techniques to overcome this limitation. In this study, the emphasis was on optimizing the extraction and formulation of a food additive based on rosemary EO. In fact, the results showed that rosemary EO extraction depended on the parameters of the extraction process, and the optimum heating temperature and extraction time were determined using an experimental design methodology. The parameters for extraction were chosen as follows: heating temperature of 250 °C and a hydrodistillation time of 180 min. This optimization revealed that the maximum oil yield can be obtained. Rosemary EO was characterized by a dominance of 1,8-cineole, camphor, α-pinene, borneol and camphene as well as by high antioxidant and antibacterial capacities with low acute toxicity. The obtained formulation of a stable rosemary EO powder can be used as a food additive in several industrial applications.

Variation in Essential Oil Content and Chemical Composition of Rosemary (Rosmarinus officinalis L.) at Various Growth Stages in the Mediterranean Region

“…When camphor content was compared by the growth stages, higher amounts were found in the pre-flowering stage. Differences in the camphor content were also reported in rosemary by other researchers, such as 11.25%-20.41% (Gürbüz et al, 2017), 1.10%-18.80% (Flamini et al, 2021), 12.40% (Christopoulou et al, 2021, 17.30%-19.07% (Dzięcioł, 2021), 14.39%-17.17% (Micić et al, 2021), 10.01%-16.20% (Elyemni et al, 2022), 7.05%-31.50% (Rathore et al, 2022), 29.46%-31.92% (Yeddes et al, 2022), 18.26% (Karakaş and Bekler, 2022). Similar to what we detected in our study, Afshar et al (2021) reported that camphor content decreased from spring (8.19%) to summer (6.95%).…”

“…Similar to the camphor content, the highest values for the 1.8-cineole content were obtained in the pre-flowering stage (22.61%). When compared the 1.8-cineole content with the earlier studies, diverse results were found, such as 6.19%-10.52% (Gürbüz et al, 2017), 41.25%-45.96% (Yıldırım, 2018), 37.50% (Khanjani et al, 2021), 10.81% (Xylia et al, 2021), 17.79%-23.40% (Micić et al, 2021), 26.40%-49.10% (Flamini et al, 2021), 40.10% (Christopoulou et al, 2021, 30.89%-31.61% (Dzięcioł, 2021), 28.97%-32.18% (Elyemni et al, 2022), 32.50%-51.79% (Rathore et al, 2022), 30.26% (Mwithiga et al, 2022), 25.26%-29.15% (Yeddes et al, 2022), 11.86% (Karakaş and Bekler, 2022).…”

Phytochemical Screening and Antibacterial Activity of Commercially Available Essential Oils Combinations with Conventional Antibiotics against Gram-Positive and Gram-Negative Bacteria

“…The EO chemical composition [ 2 ] includes phenolic compounds, terpenes, terpenoids [ 3 ], phenylpropanoids, and other aliphatic and aromatic constituents with strong lipophilic properties [ 4 ]. Their content varies depending on seasonal variations, climate, sub-species, and even the oil extraction method [ 5 , 6 ], which can lead to consequences for their antibacterial activity [ 7 ]. Investigating the EO antibacterial action is essential, considering the interactions between the main constituents and various mechanisms [ 8 ].…”

Extraction of essential oils by hydrodistillation of four aromatic species: Conditioning, extraction conditions, yield and chemical composition

“…Furthermore, natural compounds can play an essential role in mitigating antimicrobial resistance in foodborne pathogens (Peralta-Canchis et al, 2024). The potential of EOs as antibacterials and herbicides has also been identified, as they are biodegradable, have a high structural diversity and can reduce natural weed resistance (Yeddes et al, 2022). The synergies between the different compounds in EOs enable them to exhibit these properties (Karalija et al, 2020;Rafya et al, 2024).…”

“…Several different extraction techniques are widely used for EO, such as steam distillation and solvent extraction (Noori & KhajeNoori, 2013). These methods usually have some drawbacks such as low extraction efficiency and selectivity, the use of large amounts of solvents, and long extraction times (Yeddes et al, 2022;Rafya et al, 2024). In many cases, the quality of the essential oil obtained by conventional methods can be influenced by hydrolysis or oxidation that may take place due to the long extraction time and/or high amount of water (Stratakos et al, 2016;Önder et al, 2024).…”