Search

Peganum harmala (P. harmala) is a folk medicinal herb used in the Sinai Peninsula (Egypt) as a remedy for central disorders. The main constituents, harmine and harmaline, have displayed therapeutic efficacy against Alzheimer’s disease (AD); however, the P. harmala potential on sensitizing central insulin to combat AD remains to be clarified. An AD-like rat model was induced by aluminum chloride (AlCl3; 50 mg/kg/day for six consecutive weeks; i.p), whereas a methanolic standardized P. harmala seed extract (187.5 mg/kg; p.o) was given to AD rats starting 2 weeks post AlCl3 exposure. Two additional groups of rats were administered either the vehicle to serve as the normal control or the vehicle + P. harmala seed extract to serve as the P. harmala control group. P. harmala enhanced cognition appraised by Y-maze and Morris water maze tests and improved histopathological structures altered by AlCl3. Additionally, it heightened the hippocampal contents of glucagon-like peptide (GLP)-1 and insulin, but abated insulin receptor substrate-1 phosphorylation at serine 307 (pS307-IRS-1). Besides, P. harmala increased phosphorylated Akt at serine 473 (pS473-Akt) and glucose transporter type (GLUT)4. The extract also curtailed the hippocampal content of beta amyloid (Aβ)42, glycogen synthase (GSK)-3β and phosphorylated tau. It also enhanced Nrf2, while reduced lipid peroxides and replenished glutathione. In conclusion, combating insulin resistance by P. harmala is a novel machinery in attenuating the insidious progression of AD by enhancing both insulin and GLP-1 trajectories in the hippocampus favoring GLUT4 production.

Objective: This study evaluates the antimicrobial potential of Mentha spp. (M. spicata L., M. xpiperita L. and M. pulegium L.) essential oils as raw and loaded solid lipid nanoparticles (SLNs)against dental caries. Design: Essentials oils extraction from fresh aerial parts of Mentha spp. was carried out using hydro distillation technique. Solid lipid nanoparticles of Mentha essential oil were prepared by w/o/w type double emulsification method. The antimicrobial activity of both pure Mentha spp. essential oils and Mentha spp. SLNs was determined against bacteria presented in saliva collected from 12 patients using agar diffusion assay. Results: Mentha spp. essential oils loaded solid lipid nanoparticles (MSLNs) were spherical shaped with sizes ranged from 111 to 202 nm and with PDI from 0.43 to 0.76, EE% between 85 and 88, and ZP of −11.8 to -40 mV. Antimicrobial results showed that MSLNs exhibited higher in vitro antimicrobial activity than pure Mentha spp. essential oil. Particularly, with an inhibition zone of 20 mm. These both MSLNs were even more active than the reference compound novobiocin. Conclusion: Our findings demonstrate that Mentha spp. essential oils as a nanostructure increase the efficiency of these natural products as antibacterial agents against caries.

The search for new sources of natural antioxidants from plant material may have beneficial therapeutic potential for those diseases associated with oxidative stress. The medicinal plant Haplophyllum tuberculatum (Forsskal) A. Juss. (Rutaceae) contains phenolic compounds as main phytochemicals; however, there are no reports on its antioxidant properties.To evaluate antioxidant and cytoprotective potential of ethanol extract of Haplophyllum tuberculatum aerial parts.Total phenol content was determined using Folin-Ciocalteu reagent; antiradical activity was measured using ORAC assay and the analysis of the major polyphenols was carried out using a HPLC-MS method. The antioxidant and cytoprotective effect were also investigated by the MTT assay and DCFH-DA method. The human astrocytoma U373-MG cell line was pretreated with ethanol extract (from 0.025 to 250 µg/mL) for 24 h, prior to 1 mM H2O2 exposure (30 min).Total phenol content was 46.2 mg gallic acid/g sample and ORAC value was 1.283 µmol TE/mg sample. Chemical constituents were methoxyflavones, flavonols (mainly quercetin derivatives), cinnamic acids and benzoic acids. In cell system model of oxidative stress, pretreatments with ethanol extract at the concentrations of 2.5, 0.25 and 0.025 µg/mL significantly attenuated H2O2-induced loss in viability by 13.5, 17 and 20.5%, respectively. Furthermore, these ethanol extract concentrations markedly inhibited intracellular ROS production with IC50 0.026 µg/mL. These findings demonstrate the beneficial properties of ethanol extract of Haplophyllum tuberculatum aerial parts, rich in phenolic compounds, as antioxidant and radical scavenger ameliorating ROS-related processes and diseases such as several neurodegenerative disorders.

Plants of the Allium genus produce sulphur compounds that give them a characteristic (alliaceous) flavour and mediate for their medicinal use. In this study, the chemical composition and antimicrobial properties of Allium cepa red cv. and A. sativum in the context of three different drying processes were assessed using metabolomics. Bulbs were dried using either microwave, air drying, or freeze drying and further subjected to chemical analysis of their composition of volatile and non-volatile metabolites. Volatiles were collected using solid phase micro-extraction (SPME) coupled to gas chromatography–mass spectrometry (GC/MS) with 42 identified volatiles including 30 sulphur compounds, four nitriles, three aromatics, and three esters. Profiling of the polar non-volatile metabolites via ultra-performance liquid chromatography coupled to high resolution MS (UPLC/MS) annotated 51 metabolites including dipeptides, flavonoids, phenolic acids, and fatty acids. Major peaks in GC/MS or UPLC/MS contributing to the discrimination between A. sativum and A. cepa red cv. were assigned to sulphur compounds and flavonoids. Whereas sulphur conjugates amounted to the major forms in A. sativum, flavonoids predominated in the chemical composition of A. cepa red cv. With regard to drying impact on Allium metabolites, notable and clear separations among specimens were revealed using principal component analysis (PCA). The PCA scores plot of the UPLC/MS dataset showed closer metabolite composition of microwave dried specimens to freeze dried ones, and distant from air dried bulbs, observed in both A. cepa and A. sativum. Compared to GC/MS, the UPLC/MS derived PCA model was more consistent and better in assessing the impact of drying on Allium metabolism. A phthalate derivative was found exclusively in a commercial garlic preparation via GC/MS, of yet unknown origin. The freeze dried samples of both Allium species exhibited stronger antimicrobial activities compared to dried specimens with A. sativum being in general more active than A. cepa red cv.

The Sinai desert in Egypt contains great variability in plants extensively used for traditional medicines such as Achillea fragrantissima, Chiliadenus montanus, Mentha longifolia and Haplophyllum tuberculatum. The essential oils extracted by hydrodistillation from the aerial parts have been analyzed. Subsequently, their potential protective activity against oxidative stress has been evaluated, employing H2O2 as oxidant inductor and astrocytes as the cell model. The chemical composition of the essential oils was analyzed by GC/MS. Most of the compounds identified in A. fragrantissima and M. longifolia samples were oxygenated monoterpene derivatives, whereas for H. tuberculatum they were monoterpenes hydrocarbons and oxygenated compounds, and for C. montanus oxygenated monoterpenes and oxygenated sesquiterpenes predominated. The in vitro evaluation of antioxidant properties, using ORAC assay, revealed that M. longifolia essential oil possessed the highest scavenging activity against peroxyl radicals, following by H. tuberculatum, A. fragrantissima and C. montanus. Under oxidative stress conditions, M. longifolia and H. tuberculatum essential oils were the only ones that protected human astrocytoma U373-MG cells against H2O2 damage. Both essential oils prevented cell death and inhibited ROS production caused by H2O2. M. longifolia essential oil was the most active, suggesting an interesting prevention role in those CNS disorders associated with oxidative stress.

The aerial parts ofMentha longifolia L. are used as herbal remedies for curing different diseases through traditional Bedouin medicine. The antioxidant activity of the ethanolic extracts of M longifolia was investigated measuring peroxyl radical-scavenging activity by ORAC assay, with Trolox (a water-soluble analogue of α-tocopherol) employed as reference compound. In addition, the total content of phenolic compounds estimated by the Folin-Ciocalteau method and the identification of the polyphenols using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) have been performed. Furthermore, the effect of these extracts on cell viability and intracellular ROS production was assayed using the U373-MG human astrocytoma cell line in a H2O2-induced oxidative stress model. Results showed that the major type of polyphenols found were benzoic acids, cinnamic acids, flavones and flavanones. The total phenolic content was 37.7 mg gallic acid/g sample and the ORAC value was 1.355 .mol TE/mg sample. The data obtained in cellular assays demonstrated that these ethanolic extracts protected H2O2-induced astrocyte damage by increasing cell viability and inhibiting production of intracellular ROS. These results suggest that the investigated extracts obtained from the aerial parts of M longifolia have antioxidant potential related to their phenol content which have important beneficial health effects, especially in those disease associated with ROS.

The aerial parts of Mentha longifolia L. are used as herbal remedies for curing different diseases through traditional Bedouin medicine. The antioxidant activity of the ethanolic extracts of M. longifolia was investigated measuring peroxyl radical-scavenging activity by ORAC assay, with Trolox (a water-soluble analogue of α-tocopherol) employed as reference compound. In addition, the total content of phenolic compounds estimated by the Folin-Ciocalteau method and the identification of the polyphenols using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) have been performed. Furthermore, the effect of these extracts on cell viability and intracellular ROS production was assayed using the U373-MG human astrocytoma cell line in a H2O2-induced oxidative stress model. Results showed that the major type of polyphenols found were benzoic acids, cinnamic acids, flavones and flavanones. The total phenolic content was 37.7 mg gallic acid/g sample and the ORAC value was 1.355 μmol TE/mg sample. The data obtained in cellular assays demonstrated that these ethanolic extracts protected H2O2-induced astrocyte damage by increasing cell viability and inhibiting production of intracellular ROS. These results suggest that the investigated extracts obtained from the aerial parts of M. longifolia have antioxidant potential related to their phenol content which have important beneficial health effects, especially in those disease associated with ROS.

The Sinai desert in Egypt contains great variability in plants extensively used for traditional medicines such as Achillea fragrantissima, Chiliadenus montanus, Mentha longifolia and Haplophyllum tuberculatum. The essential oils extracted by hydrodistillation from the aerial parts have been analyzed. Subsequently, their potential protective activity against oxidative stress has been evaluated, employing H2O2 as oxidant inductor and astrocytes as the cell model. The chemical composition of the essential oils was analyzed by GC/MS. Most of the compounds identified in A. fragrantissima and M. longifolia samples were oxygenated monoterpene derivatives, whereas for H. tuberculatum they were monoterpenes hydrocarbons and oxygenated compounds, and for C. montanus oxygenated monoterpenes and oxygenated sesquiterpenes predominated. The in vitro evaluation of antioxidant properties, using ORAC assay, revealed that M. longifolia essential oil possessed the highest scavenging activity against peroxyl radicals, following by H. tuberculatum, A. fragrantissima and C. montanus. Under oxidative stress conditions, M. longifolia and H. tuberculatum essential oils were the only ones that protected human astrocytoma U373-MG cells against H2O2 damage. Both essential oils prevented cell death and inhibited ROS production caused by H2O2. M. longifolia essential oil was the most active, suggesting an interesting prevention role in those CNS disorders associated with oxidative stress.