Chemical Composition and Cytotoxic and Antibacterial Activities of the Essential Oil of Aloysia citriodora

The aim of this work is to investigate the in vitro cytotoxic and antibacterial effects of the essential oils of Aloysia citriodora Palau, harvested in different regions of Morocco. The chemical profile was established using gas chromatography-mass spectrometry analysis. The cytotoxic activity against P815, MCF7, and VERO cell lines as well as the normal human peripheral blood mononuclear cells (PBMCs) was evaluated using the MTT assay. Standard, ATCC, strains of bacteria (Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa) were cultivated in Muller Hinton media. Then, agar disc diffusion, minimum inhibitory concentrations (MICs), and minimal bactericidal concentrations (MBCs) were determined using microdilution method. The essential oils obtained were predominantly composed of β-spathulenol (15.61%), Ar-curcumene (14.15%), trans-caryophyllene oxide (14.14%), and neral (10.02%). The results of the assays showed that the cytotoxic effect of the essential oil of A. citriodora was high on P815 and moderate on MCF7 and on VERO cell lines. However, no cytotoxic effect was observed on PBMCs. On the other hand, essential oils showed a significant antimicrobial activity against both Gram-negative and Gram-positive bacteria. MICs ranged between 2.84 and 8.37 mg/ml. Essential oil of A. citriodora leaves possesses significant antibacterial effect and cytotoxic activity against tumor cell lines

Hemisynthesis and evaluation of pharmacological activities of carvacrol-derivatives

Hemi-synthesis, a process widely used in pharmacological research, consists of a modification in the chemical structure of a natural product in order to improve its activity and/or to reduce its side effects. Two carvacrol-derivatives (P1 and P2) have been synthetized using reactions of alkylation by binding alkan groups at the hydroxyl group of carvacrol. NMR analysis was performed for synthetized derivatives to confirm the success of the reactions. Then, cytotoxic activity, against two tumour cell lines (P-815 and MCF-7), and antibacterial activity of carvacrol, P1 and P2 were performed. Cytotoxicity was measured using the colourimetric methyl tetrazolium test (MTT) and antimicrobial activity was measured using the diffusion technique on solid media and the determination of CMI on liquid media. Our results show that chemical modifications made on carvacrol have no effect on its antitumor activity. However, an important decrease of its antibacterial activity was observed, especially for P1. Our results suggest that hydroxyl group at this position of the molecule may be responsible for carvacrol antibacterial activity, while the other parts of the molecule may be responsible for its antitumor activity. On the other hand, introduced modifications may affect mechanism of action of the molecules as well as its pharmacokinetics properties

Identification and characterisation of phenolic compounds extracted from Moroccan olive mill wastewater

Olive mill wastewater, hereafter noted as OMWW was tested for its composition in phenolic compounds according to geographical areas of olive tree, i.e. the plain and the mountainous areas of Tadla-Azilal region (central Morocco). Biophenols extraction with ethyl acetate was efficient and the phenolic extract from the mountainous areas had the highest concentration of total phenols' content. Fourier-Transform-Middle Infrared (FT-MIR) spectroscopy of the extracts revealed vibration bands corresponding to acid, alcohol and ketone functions. Additionally, HPLC-ESI-MS analyses showed that phenolic alcohols, phenolic acids, flavonoids, secoiridoids and derivatives and lignans represent the most abundant phenolic compounds. Nüzhenide, naringenin and long chain polymeric substances were also detected. Mountainous areas also presented the most effective DPPH scavenging potential compared to plain areas; IC50 values were 11.7 ± 5.6 µg/ml and 30.7 ± 4.4 µg/ml, respectively. OMWW was confirmed as a rich source of natural phenolic antioxidant agents

Hemisynthesis and evaluation of pharmacological activities of carvacrolderivatives

537-542Hemi-synthesis, a process widely used in pharmacological research, consists of a modification in the chemical structure of a natural product in order to improve its activity and/or to reduce its side effects. Two carvacrol-derivatives (P1 and P2) have been synthetized using reactions of alkylation by binding alkan groups at the hydroxyl group of carvacrol. NMR analysis was performed for synthetized derivatives to confirm the success of the reactions. Then, cytotoxic activity, against two tumour cell lines (P-815 and MCF-7), and antibacterial activity of carvacrol, P1 and P2 were performed. Cytotoxicity was measured using the colourimetric methyl tetrazolium test (MTT) and antimicrobial activity was measured using the diffusion technique on solid media and the determination of CMI on liquid media. Our results show that chemical modifications made on carvacrol have no effect on its antitumor activity. However, an important decrease of its antibacterial activity was observed, especially for P1. Our results suggest that hydroxyl group at this position of the molecule may be responsible for carvacrol antibacterial activity, while the other parts of the molecule may be responsible for its antitumor activity. On the other hand, introduced modifications may affect mechanism of action of the molecules as well as its pharmacokinetics properties