extract on human peripheral blood mononuclear cells are mediated by TLR-4 and NF-κB suppression

There is great interest in evaluating the anti-inflammatory properties of new herbal products. Thus, the effects of Mentha pulegium L. extract on gene and protein expressions of pro-inflammatory mediators and transcription factors were determined. The hydro-ethanolic extract of Mentha pulegium L. was obtained and optimal non-cytotoxic concentrations of the extract were determined by MTT assay. Then, three different concentrations of Mentha pulegium L. (10, 30, and 90 μg/mL) were used to pre-treat the lipopolysaccharide (LPS)-stimulated and non-stimulated peripheral blood mononuclear cells (PBMCs) of 10 healthy individuals. Finally, the tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, Toll-like receptor-4 (TLR-4), nuclear factor-kappa B (NF-κB) p65, activator protein-1 (AP-1), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) gene expressions and TNF-α, IL-1β, IL-6, TLR-4, prostaglandin E2 (PGE2), and COX-2 protein levels were measured. MTT results showed that there is no significant difference in cell viability among 10, 20, 40, and 80 μg/mL concentrations of Mentha pulegium L. extract at 24, 48, and 72 h (P > 0.05). The IC50 values were 236.1, 147.0, and 118.0 μg/mL after 24, 48, and 72 h respectively. TNF-α, IL-1β, IL-6, TLR-4, iNOS, and NF-κB p65 mRNA levels in the pre-treated LPS-stimulated PBMCs were concentration-dependently reduced (P < 0.01 for TNF-α, TLR-4, and NF-κB p65; P < 0.05 for IL-1β, IL-6, and iNOS). Also, the protein levels of pro-inflammatory mediators decreased and these differences were significant for TNF-α, IL-1β, and TLR-4 (P < 0.001, P < 0.01, and P < 0.001, respectively). Mentha pulegium L. extract decreased the expression and biosynthesis of pro-inflammatory mediators. These effects are mainly mediated by TLR-4 and NF-κB suppression. Thus, Mentha pulegium L. could be useful in treating or ameliorating chronic inflammatory diseases.

Novel Approach for a Controlled Delivery of Essential Oils during Long-Term Maize Storage: Clove Bud and Pennyroyal Oils Efficacy to Control Sitophilus zeamais, Reducing Grain Damage and Post-Harvest Losses

Maize grains represent a significant contribution for assuring food safety all over the globe. Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), also known as the maize weevil, is one of the most destructive pests in stored maize, causing qualitative and quantitative losses. To control S. zeamais populations in maize storage sites, synthetical chemical insecticides are applied. However, these are often used wastefully, have environmental implications, and can induce the development of resistant populations. In this work, the insecticidal and grain protecting efficacy of an innovative macro-capsule delivery device, loaded with essential oils from Clove bud and Pennyroyal, as well as their combined solutions, was tested against naturally S. zeamais-infested maize grains. The blend of both compounds incorporated in a controlled release device reduced losses by more than 45% over a long storage period of twenty weeks, diminishing the survivability of maize weevils by over 90%. The usage of the blend at a concentration of 370 μL⋅Lair-1 with an antioxidant showed the best results, however, by halving the concentration (185 μL⋅Lair-1), a significant control of S. zeamais populations was still achieved.

Response surface modeling and optimization of the extraction conditions using lactic acid-based deep eutectic solvents as green alternative extraction media for Mentha pulegium

INTRODUCTION

Most recurrently available organic solvents are toxic and inflammable and pose high risks to human health. Natural deep eutectic solvents (NADESs) have been developed as promising green alternatives.

OBJECTIVE

We aimed to extract polyphenolic compounds from Mentha pulegium using lactic acid-based deep eutectic solvents. Extraction parameters were optimized by response surface methodology.

MATERIAL AND METHODS

Combined with ultrasound-assisted extraction, three different lactic acid-based deep eutectic solvents were investigated for the extraction of polyphenols. Methanol (80%, v/v) was used for comparison. The optimized influencing factors were: water content in solvent, extraction time, and temperature. The design was adopted including 17 experiments with three center points.

RESULTS

All NADESs tested showed an excellent extraction efficacy compared to 80% methanol. Under the optimized conditions, with 45% of water, at 30°C, and for extraction 90 min, the highest extraction yields were recorded using lactic acid:sodium acetate (3:1), achieving 173.35 ± 0.02 mg gallic acid equivalents (GAE)/g dry weight (dw) of polyphenols and 95 ± 0.09% antioxidant activity. After extraction for 90 min at 80°C with 18% of water, we obtained 164.06 ± 0.01 mg GAE/g dw and 94 ± 0.02% antioxidant activity using lactic acid:glucose (5:1). Efficient recovery (64.92 ± 0.01 mg GAE/g dw and 97 ± 0.1% antioxidant activity) was achieved using lactic acid:glycine (3:1) with 31% of water, at 35°C, and extraction for 30 min.

CONCLUSION

Our results indicate that with optimized parameters, the proposed natural solvents are excellent alternatives to chemical ones for the extraction of phenolic compounds.

Insecticidal Effect of Wild-Grown Mentha pulegium and Rosmarinus officinalis Essential Oils and Their Main Monoterpenes against Culex pipiens (Diptera: Culicidae)

The present study investigates the insecticidal effect of plant extract such as Mentha pulegium and Rosmarinus officinalis essential oils and some of their major compounds; these plants are well known for their many biological activities. The fumigant toxicity was evaluated, using glass jars, against female adults of Culex pipiens that constitute a mosquito vector of important diseases such as the West Nile virus. The adulticidal test showed that both essential oils and monoterpenes presented an insecticidal effect better than the chemical insecticide (Deltamethrin). The highest mortality percentages for the two essential oils have occurred at 312.5 µL/L air (between 56.14 ± 1.7% and 97.71 ± 3.03% after 24 h and 48 h of treatment). Moreover, all tested monoterpenes (carvone, R(+)-pulegone, 1,8-cineole, camphor and α-pinene) have produced high mortalities that varied depending on the time of the treatment and the concentrations used. Lethal concentrations (LC50) obtained for the essential oils and the main compounds have also varied according to the exposure time. M. pulegium and R. officinalis essential oil exhibited the lowest LC50 values after 24 h (72.94 and 222.82 µL/L air, respectively) and after 48 h (25.43 and 55.79 µL/L air, respectively) while the pure molecules revealed the lowest LC50 values after 48 h (between 84.96 and 578.84 µL/L air). This finding proves that the two essential oils and their main compounds have an insecticidal potential, which could help to develop natural toxic fumigants that may be used as an eco-friendly alternative in integrated and sustainable vector management.

Effect of Extraction Methods on Polyphenols, Flavonoids, Mineral Elements, and Biological Activities of Essential Oil and Extracts of Mentha pulegium L

Our study evaluated the in vitro antioxidant properties, antibacterial and antifungal activities, anti-inflammatory properties, and chemical composition of the essential oils (EOs), total phenol, and total flavonoid of wild Mentha pulegium L. This study also determined the mineral (nutritional and toxic) elements in the plant. The EOs were extracted using three techniques-hydro distillation (HD), steam distillation (SD), and microwave-assisted distillation (MAD)-and were analyzed using chromatography coupled with flame ionization (GC-FID) and gas chromatography attached with mass spectrometry detector (GC-MS). The antioxidant effects of the EOs were tested with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), while the antibacterial and antifungal activities of the EO and methanolic extract were tested using Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Twenty-six compounds were identified in the essential oil, representing 97.73% of the total oil, with 0.202% yield. The major components were pulegone (74.81%), menthone (13.01%) and piperitone (3.82%). Twenty-one elements, including macro- and micro-elements (Ba, Br, Ca, Cl, Co, Cr, Cs, Eu, Fe, K, Mg, Mn, Mo, Na, Rb, Sb, Sc, Sr, Th, U and Zn), were detected using neutron activation analysis (INAA) and inductively coupled plasma optical emission spectrometry (ICP-OES), with the concentration of mineral element close to the FAO recommendation. The results show that the EOs and extracts from Mentha pulegium L. had significant antimicrobial activities against the microorganisms, including five human pathogenic bacteria, one yeast (Candida albicans), and one phytopathogenic fungi. The in vivo anti-inflammatory activities of the leaf extracts were confirmed. The results indicate that the EOs and extracts from Mentha pulegium L. have promising applications in the pharmaceutical industries, clinical applications, and in medical research.

Screening of the Potential Bioactivities of Pennyroyal (Mentha pulegium L.) Essential Oil

Increasing resistance of pathogens towards conventional antibiotics presents a major threat to public health because it reduces the effectiveness of antibiotic treatment. Mentha pulegium L., also known as pennyroyal, is an aromatic herb that belongs to the family Lamiaceae. Its essential oil has been traditionally used in medicine, aromatherapy, and cosmetics. The purpose of this work was to study the chemical composition of a pennyroyal essential oil and to evaluate their bioactivities, specifically, antioxidant, antimicrobial, anti-quorum sensing, and anti-inflammatory. A special focus was given to the antibacterial activity of the essential oil against Acinetobacter baumannii. The chemical composition of the essential oil was studied by GC-MS/GC-FID. The DPPH free radical scavenging assay and the β-carotene/linoleic acid system were used to evaluate the antioxidant properties. The antimicrobial and anti-quorum sensing activities were evaluated by disk diffusion assays and complemented with optical microscopy observations. The results showed that pulegone was the major compound (88.64%) of the pennyroyal essential oil. Regarding the antimicrobial activity, the action against Acinetobacter baumannii stands out, which, together with the capacity of the essential oil to inhibit the quorum sensing mechanisms, may suggest the use of the pennyroyal essential oil to further develop surface disinfectants for hospitals.

Antibacterial Activities of Phytofabricated ZnO and CuO NPs by Mentha pulegium Leaf/Flower Mixture Extract against Antibiotic Resistant Bacteria

Purpose: In this study, leaf/flower aqueous extract of medicinal plant species Mentha pulegium was used to synthesize ZnO and CuO nanoparticles (NPs) as a cost-effective, one-step, and eco-friendly method. Methods: Physicochemical properties of both metal oxide NPs (MONPs) were determined by UV-Vis spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM) and energy dispersive X-ray (EDX) techniques. Results: Phytofabricated ZnONPs and CuNPs illustrated 65.02±7.55 and 26.92±4.7 nm with antibacterial activities against antibiotic-resistant Escherichia coli and Staphylococcus aureus. Higher antibacterial activities were observed for CuONPs compared with ZnONPs. Conclusion: Large surface area and more reactivity resulted from smaller size as well as higher production of reactive oxygen species (ROS) were considered to antibacterial efficiency of CuONPs against antibiotic-resistant E. coli and S. aureus.

In vitro activities of Traganum nudatum and Mentha pulegium extracts combined with amphotericin B against Candida albicans in production of hydrolytic enzymes

Background and Purpose :

Candida albicans is an important microorganism in the normal flora of a healthy subject; however, it has an expedient pathogenic character that induces hydrolytic virulence. Regarding this, the present study aimed to find an in vitro alternative that could reduce the virulence of this yeast.

Materials and Methods:

For the purpose of the study, the effect of amphotericin B (AmB) combined with the extract of Traganum nudatum (E1) or Mentha pulegium (E2) was evaluated against the hydrolytic activities of esterase, protease, and phospholipase. This effect was determined by calculating the minimum inhibitory concentration (MIC), used to adjust the extract/AmB mixtures in culture media.

Results:

The evaluated Pz values, which corresponded to the different enzymatic activities, showed a decrease in the hydrolytic activities of C. albicans strains after the addition of E1/AmB and E2/AmB combinations at descending concentrations (lower than the obtained MICs).

Conclusion:

Based on the findings, it would be possible to reduce the pathogenesis of this species without destabilizing the balance of the flora.

Essential oil of Mentha pulegium induces anthelmintic effects and reduces parasite-associated oxidative stress in rodent model

Following the previous findings reported by the present authors on the anthelmintic effect of hydro-ethanolic extract of Mentha pulegium, the volatile constituents of M. pulegium are now assessed in the present study by exploring its anthelmintic and its antioxidant proprieties using in vitro and in vivo assays. Egg hatch assay (EHA) and adult worm's motility assays (AWMA) were used to assess the in vitro activity against Haemonchus. contortus. The in vivo anthelmintic potential was evaluated in mice infected with Heligmosomoides polygyrus using faecal egg count reduction (FECR) and total worm count reduction (TWCR). M. pulegium EO demonstrated 100% inhibition in the EHA at 200 μg/mL (IC50 = 56.36 μg/mL). In the AWM assay, EO achieved total worms paralysis 6 h after treatment exposure. This nematicidal effect was associated to morphological damages observed in the cuticular's worm using environmental scanning electron microscopy (ESEM). At 400 mg/kg, M. pulegium oil showed 75.66% of FECR and 80.23% of TWCR. The antioxidant potential of this plant was also monitored by several in vitro assays: total antioxidant capacity was 205.22 mg GAE/g DW, DPPH quenching effect was IC50 = 140 μg/mL, ABTS activity IC50 = 155 μg/mL and FRAP effect of 660 μg/mL. Regarding the in vivo assay, M. pulegium EO demonstrated a protective effect against oxidative stress by increasing the activity of the endogenous antioxidants (SOD, CAT and GPx) during H. polygyrus infection.

in Rats: An In vitro and In vivo Approach

Aims The aim of the study was to investigate the effect of aqueous aerial part extract of Mentha pulegium L. (Pennyrile) (MPAE) on arterial pressure parameters in rats.

BACKGROUND

Mentha pulegium is a medicinal plant used to treat hypertension in the Moroccon population.

METHODS

In the current study, MPAE was prepared and its antihypertensive activity was pharmacologically investigated. L-NAME-hypertensive and normotensive rats received MPAE (180 and 300 mg/kg) orally for six hours for acute experiment and during seven days for the sub-chronic treatment. Thereafter, systolic, diastolic, mean arterial blood pressure and heart rate were evaluated. In the in vitro experiment, isolated denuded and intact thoracic aortic rings were suspended in a tissue bath system and the tension changes were recorded.

RESULTS

A fall in blood pressure was observed in L-NAME-induced hypertensive treated with MPAE. The extract also produced a dose-dependent relaxation of aorta pre-contracted with NE and KCl. The study showed that the vasorelaxant ability of MPAE seems to be exerted through the blockage of extracellular Ca2+ entry.

CONCLUSION

The results demonstrate that the extract of pennyrile exhibits antihypertensive activity. In addition, the effect may be, at least in part, due to the dilation of blood vessels via blockage of Ca2+ channels.

Green Synthesis and Characterization of Bismuth Oxide Nanoparticle Using Mentha Pulegium Extract

In recent years, green synthesis of nanoparticles has attracted a great attention because of medicine and biological applications. In this work, bismuth oxide nanoparticles (Bi₂O₃ NP) was prepared via green synthesis using mentha pulegium aqueous extract after 24 h at 90°C. The product was characterized by ultraviolet-visible (UV-VIS) spectrophotometer, Fourier transform infrared (FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS), scanning electron microscopy (SEM), transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDS), and diffuse reflection spectroscopy (DRS). The antibacterial activities of the samples were determined against Salmonella and Escherichia coli (E.Coli) as Gram-negative bacterial and Staphylococcus aureus (S.aureus) as Gram-positive bacterial. The objectives of this study were the green synthesis of bismuth oxide nanoparticles using aqueous extract with a good potential for UV blocking and antibacterial activity. Based on the obtained results, Bi₂O₃ NPs can have a good candidate for different applications.

Chemical composition, antioxidant capacity and antibacterial action of five Moroccan essential oils against Listeria monocytogenes and different serotypes of Salmonella enterica

Essential oils (EOs) obtained from aromatic plants are rich in natural components with interesting antimicrobial effects. The aim of this study was to evaluate the chemical composition of EOs extracted from Origanum majorana (OM-EO), Mentha suaveolens (MS-EO), Rosmarinus officinalis (RO-EO), Salvia officinalis (SO-EO) and Mentha pulegium (MP-EO). Their antioxidant properties and antibacterial activity against Listeria monocytogenes and different serotypes of Salmonella enterica subsp. enterica were also studied. The EOs were extracted from plants by hydro-distillation and their chemical composition was determined by GC-MS. Terpinen-4-ol, 1,8-Cineole, Camphor, Limonene and Cinerone were the main chemical components found in OM-EO, RO-EO, SO-EO, MP-EO and MS-EO, respectively. To the best of our knowledge, Limonene and Cinerone were reported, for the first time, as the major components of MP-EO and MS-EO. Moreover, our results showed that MS-EO had the best antioxidant activity with an IC₅₀ of 0.78 ± 0.05 mg/mL, EC₅₀ of 1.53 ± 0.07 mg/mL, and RC₅₀ of 0.98 ± 0.04 mg/mL, and the higher antibacterial activity using microdilution broth method with MIC of 0.5% for Salmonella and 0.25% for L. monocytogenes, while OM-EO had the best antibacterial activity using disc diffusion method (inhibition diameters ranged between 15.3 ± 0.3 mm and 18.5 ± 0.3 mm for Salmonella and between 20.1 ± 0.2 mm and 25.4 ± 0.4 mm for L. monocytogenes). However, OM-EO and MS-EO present the higher percentage of sub-lethally injured cells against S. enterica (5.50 ± 0.11%) and L. monocytogenes (5.23 ± 0.07%), respectively. From this study, we can conclude that the investigated EOs are rich in components with interesting antibacterial activity and they could be applied in food preparations as natural preservatives to extend the shelf life of food products and to inhibit the growth of food-borne pathogens.

Discrimination of Mentha species grown in different geographical areas of Algeria using 1H-NMR-based metabolomics

¹H-NMR-based metabolomics have been applied to identify potential NMR-markers and biomarkers capable of distinguishing, qualifying and classifying three Mentha species:- Mentha pulegium L., Mentha × rotundifolia (L.) Huds., Mentha spicata L., and their ecotypes. Samples of the 3 species were collected in seven different locations in Algeria, with the aim to establish a quality control protocol based on the use of NMR fingerprint profiles of polar extracts. NMR data indicate that the identification of the Mentha genus can be confirmed by the presence of the doublet proton signals with identical coupling constants at δ 7.49 (d, 15.9 Hz) and δ 6.29 (d, 15.9 Hz); these correspond to the protons of the double-bond conjugated to the ester group of rosmarinic acid, a bioactive compound found in all three species. Differences in NMR proton chemical shifts and/or signal intensities were clearly demonstrated on the orthogonal projections to latent structures discriminating analysis (OPLS-DA). Several potential biomarkers discriminating the three Mentha species were originated using S-plots, loading score plots, NMR data analysis and literature search. These discriminating signals point to glycosylated flavonols, oxygenated terpenoids and hydrocarbon terpenoids to distinguish M. pulegium, M. × rotundifolia and M. spicata, respectively. Within the same species, Principal Component Analysis (PCA) scores clearly discriminated the metabolite content according to regions in which the plants were grown. The 6 zones in which Mentha pulegium samples were harvested were clearly separated along either or both PC1 and PC2; by contrast, the harvesting locations were divided into two groups along PC1 for both M. × rotundifolia and M. spicata. The total antioxidant activity of the Mentha species was impacted by the abiotic factors of the different regions.

Hydro-Ethanolic Extract of Mentha pulegium Exhibit Anthelmintic and Antioxidant Proprieties In Vitro and In Vivo

INTRODUCTION

During recent decades, the emergence of chemoresistance among synthetic anthelmintic drugs has increased the interest in screening novel natural anthelmintic compounds derived from plants. The current study is aimed to determine the chemical profile, anthelmintic and antioxidant properties of Mentha pulegium hydro-ethanolic extract.

MATERIALS AND METHODS

Two tests were used to assess the in vitro anthelmintic activity of the hydro-ethanolic extract of M. pulegium against Haemonchus contortus; egg hatch assay (EHA) and adult worm motility (AWM) assay. M. pulegium extracts at the doses of 500, 1000, 2000 and 4000 mg/kg were evaluated in vivo in mice infected with Heligmosomoides polygyrus. The anthelmintic efficacy was monitored using faecal egg count reduction (FECR) and total worm count reduction (TWCR). The antioxidant activity of M. pulegium extract was evaluated by testing the total antioxidant capacity and the DPPH free radical-scavenging ability.

RESULTS

Chromatographic characterization of M. pulegium composition using RP-HPLC revealed the presence of phenolic acids such as syringic acid, ferulic acid and the presence of flavonoid compounds, such as isorhamnetin-3-O-glucoside and kaempferol-3-O-rutinoside. We observed 91.58% inhibition in the EHA at 8 mg/mL after 48 h of incubation (IC50=1.82 mg/mL). In the AWM assay, M. pulegium extract achieved 65.2% inhibition at 8 mg/mL after 8 h. The highest dose (4000 mg/kg) showed a significant nematicidal effect 7 days post-treatment by inducing 60.39% FECR and 71.6% TWCR. We also report strong in vivo antioxidant capacity of the extract, as revealed by a significant increase of the enzymatic activities of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymes in mice infected with H. polygyrus.

CONCLUSION

Together, the results in this paper suggest that M. pulegium possesses anthelmintic properties and could be a potential source of novel compounds for the control of helminth parasites as well as its associated oxidative damage.

Chemical Composition, Antioxidant, Anti-Tyrosinase, Anti-Cholinesterase and Cytotoxic Activities of Essential Oils of Six Algerian Plants

In this study, the essential oils (EOs) of six Algerian plants (Artemisia campestris L., Artemisia herba-alba Asso, Juniperus phoenicea L., Juniperus oxycedrus L., Mentha pulegium L. and Lavandula officinalis Chaix) were obtained by hydrodistillation, and their compositions determined by GC-MS and GC-FID. The antioxidant activity of the EOS was evaluated via 2,2'-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing/antioxidant power (FRAP) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assays. Moreover, their cytotoxic effect was evaluated-as well as their tyrosinase, acetyl- and butyryl-cholinesterase (AChE and BuChE) inhibitory activities. The chemical analyses detected 44, 45, 51, 53, 26 and 40 compounds in EOs of A. campestris, A. herba-alba, J. phoenicea, J. oxycedrus, M. pulegium and L. officinalis, respectively. A. campestris EO was mainly composed of β-pinene (20.7%), while A. herba-alba EO contained davanone D (49.5%) as the main component. α-Pinene (41.8%) was detected as the major constituent in both J. phoenicea (41.8%) and J. oxycedrus (37.8%) EOs. M. pulegium EO was characterized by pulegone as the most abundant (76.9%) compound, while linalool (35.8%) was detected as a major constituent in L. officinalis EO. The antioxidant power evaluation revealed IC50 values ranging from 2.61 to 91.25 mg/mL for DPPH scavenging activity, while the FRAP values ranged from 0.97-8.17 µmol Trolox equivalents (TX)/g sample. In the ABTS assay, the values ranged from 7.01 to 2.40 µmol TX/g sample. In the presence of 1 mg/mL of the samples, tyrosinase inhibition rates ranged from 11.35% to 39.65%, AChE inhibition rates ranged from 40.57% to 73.60% and BuChE inhibition rates ranged from 6.47% to 72.03%. A significant cytotoxic effect was found for A. herba-alba EO. The obtained results support some of the traditional uses of these species in food preservation and for protection against several diseases.

Reduction of inflammation and colon injury by a Pennyroyal phenolic extract in experimental inflammatory bowel disease in mice

PURPOSE

Little is known about the pharmacological effects of the phenolic compounds of Pennyroyal (Mentha pulegium). This Mediterranean aromatic plant, used as a gastronomic spice and as food preservative by the food industry has been studied mainly due to its essential oil antibacterial properties, composed primarily by monoterpenes. With this work, we aimed to evaluate the effects of a phenolic extract of pennyroyal in the impairment of inflammatory processes in Inflammatory Bowel Diseases (IBD) and in the potential inhibition of progression to colorectal cancer (CRC).

METHODS

To that purpose, we evaluated the effect of pennyroyal extract administration in a model of TNBS-induced colitis in mice and further determined its effect on human colon carcinoma cell proliferation and invasion.

RESULTS

The phenolic extract of pennyroyal exhibited antioxidant properties in in vitro assays and administration of the extract in a rat model of carrageenan-induced paw oedema led to significant anti-inflammatory effects. Further results evidenced a beneficial effect of the phenolic extract in the attenuation of experimental colitis and a potential antiproliferative effect on cultured colon cancer cells, effects not previously described, to our knowledge. A reduction in several markers of colon inflammation was observed following administration of the extract to colitis-induced mice, including functional and histological indicators. A successful inhibition of cancer cell invasion and proliferation was also observed in in vitro studies with HT-29 cells. Furthermore, the extract also led to a reduced expression of iNOS/COX-2 in the colon of colitis-induced mice, both being crucial mediators of intestinal inflammation.

CONCLUSIONS

Taking into consideration the central role of inflammation in the pathophysiology of CRC and the recognised connection between inflammatory events and cancer, these results enlighten the relevance of the phenolic constituents of pennyroyal as important pharmacological sources in the investigation of new treatment options for patients with inflammatory bowel diseases.

Encapsulation of Mentha pulegium Essential Oil in Yeast Cell Microcarriers: An Approach to Environmentally Friendly Pesticides

A green approach for the encapsulation of Mentha pulegium essential oil in commercial baker's yeast and its evaluation as a pesticide against the insect pest Myzus persicae are presented. Upon treating aqueous yeast cell dispersion with the essential oil, the formation of essential-oil-loaded microparticles of about 9 μm is observed, with a loading capacity ranging from 29 to 36%, depending upon the encapsulation conditions. The thermal properties of the microparticles were characterized using differential scanning calorimetry and thermogravimetric analysis, confirming the protection of the essential oil from the cells. Encapsulation prolonged the insecticidal activity of the essential oil by 3 days.

Phytochemical Composition, Antioxidant Potential and Cholinesterase Inhibition Potential of Extracts from Mentha pulegium L

The aim of this work was to perform the phytochemical analysis as well as antioxidant and anticholinesterase potential of hot water and methanolic extracts from Mentha pulegium L., Lamiaceae, wild growing in Bosnia and Herzegovina. It is a plant that is traditionally used in Bosnia and Herzegovina medicine to treat gastrointestinal and neurological disorders. By HPLC-DAD analysis of tested extracts, 15 phenol compounds were identified and quantified. Rosmarinic acid was the most abundant compound in both extracts, followed by ellagic acid, eriodictyol, naringenin and chlorogenic acid. Both extracts were demonstrated good radical scavenging potential, reducing power and ability to inhibit lipid oxidation. The tested extracts also showed low ability to inhibit protein oxidation and low or no acetylcholinesterase and butyrylcholinesterase inhibition potential. The promising radical scavenging potential, reducing power and lipid protection potential of tested extracts indicates that the extracts of M. pulegium could be useful in preventing free radical linked diseases, as well as food protecting antioxidants.

Essential oils from Algerian species of Mentha as new bio-control agents against phytopathogen strains

Chemical composition and antifungal activity of essential oils of Algerian Mentha species were studied. Chemical compositions of different Mentha species oils (Mentha rotundifolia, M. spicata, M. pulegium, and M. piperita) were investigated by capillary GC and GC/MS, and their antifungal activities were evaluated by means of paper disc diffusion method and minimum inhibitory concentration (MIC) assays. In total, 98 components from all Mentha species were identified. All oils were rich in monoterpene-oxygenated components. In addition, we reported fumigant antifungal activity of Algerian Mentha essential oils against four fungi: Botrytis cinerea, Penicillium expansum, Monilinia laxa, and M. fructigena. All oils demonstrated very good inhibition especially against B. cinerea, M. laxa, and M. fructigena. Both Monilinia fungi were extremely sensitive to all Algerian Mentha oils, which suggests that Mentha essential oils have the potential to be used as bio-pesticides to protect fruit trees, such as apple and pear trees, and provides an alternative to chemical pesticides.

Chemical composition of Mentha pulegium and Rosmarinus officinalis essential oils and their antileishmanial, antibacterial and antioxidant activities

The aim of the study was the determination of the chemical composition of Mentha pulegium L. and Rosmarinus officinalis L. essential oils and the evaluation of their antileishmanial, antibacterial and antioxidant activities. Essential oils (EOs) were isolated using steam distillation and the chemical composition was determined using GC-MS analysis. The antibacterial activity was tested against ten pathogenic strains using the diffusion method, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by microtitration assay. The antioxidant activity was estimated by DPPH free radical scavenging ability and ferric-reducing power. The antileishmanial activity was tested against Leishmania major, Leishmania tropica and Leishmania infantum using MTT (3-(4.5-dimethylthiazol-2yl)-2.5-diphenyltetrazolium bromide) assay. The yield of essential oils (v/w %) M. puleguim and R. officinalis based on dry weight were 5.4 and 2.7% respectively. GC/MS analysis of R. officinalis essential oil (ROEO) revealed the presence of 29 components, mainly represented by oxygenated monoterpenes (63.743%) and hydrocarbons monoterpenes (21.231%). Mentha pulegium essential oil (MPEO) revealed 21 components, mainly represented by oxygenated monoterpenes (83.865%). The major components of ROEO were α-pinene (14.076), 1,8-Cineole (23.673) and camphor (18.743), while menthone (21.164) and pulegone (40.98) were the main major components of MPEO. M. pulegium and R. officinalis EOs showed a significant antioxidant activity compared with ascorbic acid and Trolox to the IC₅₀ values of 58.27 ± 2.72 and 85.74 ± 7.57 μg/mL respectively revealed by reducing power assay. As for the antibacterial effect, the highest zone diameters were shown by the MPEO against Bacillus subtilis (30 ± 1.43 mm) and Proteus mirabilis (28 ± 1.32 mm). These values are significantly important compared with those of the commercialized antibiotic (Erythromycin and Chlorophenicol). The lowest MIC and MBC values were obtained with MPEO against S. aureus MBLA (MIC = MBC = 0.25% (v/v)). While, ROEO has exhibited a bactericidal effect against Listeria monocytogenes (MIC = MBC = 0.5% (v/v)), Bacillus subtilis (MIC = MBC = 1% (v/v)) and Escherichia coli (MIC = MBC = 1% (v/v)). For the antileishmanial effect, ROEO is the most active against L. major (IC₅₀ = 1.2 ± 0.36 μg/mL. While, the MPEO has the most leishmanicidal effect against L. major (IC₅₀ = 1.3 ± 0.45 μg/mL). These findings show that the EOs of M. pulegium and R. officinalis are good sources of bioactive molecules that could have potential applications in the food and pharmaceutical industries.

Efficacy of Mentha pulegium extract in the treatment of functional dyspepsia: A randomized double-blind placebo-controlled clinical trial

ETHNOPHARMACOLOGICAL EVIDENCE

Mentha pulegium L. leaves are used in the Iranian traditional medicine for the treatment of functional dyspepsia.

AIM OF STUDY

To study the efficacy and safety of M. pulegium in the treatment of functional dyspepsia patients fulfilling the Rome III criteria.

MATERIALS AND METHODS

The efficacy and safety of a standardized Mentha pulegium leaf extract (drug extract ratio: 15.9:1, extraction solvent: 70% v/v aqueous ethanol) (330mg three times daily taken for 2 months) as add-on to one famotidine 40mg tablet per day in the treatment of 50 functional dyspepsia patients were compared with those of a parallel placebo group (n =50).

RESULTS

The extract significantly decreased the total dyspepsia score measured by the Hong Kong dyspepsia index compared to the placebo and baseline (P=0.011 and P<0.001 respectively). The stomach pain, upper abdominal bloating, upper abdominal dull ache, belching and total dyspepsia scores were decreased from baseline in the extract group significantly compared to the placebo (P<0.001, P<0.001, P=0.003, P<0.001 and P<0.001 respectively). However, the decreases of other dyspepsia symptoms scores from baseline in the extract group were not significant compared to the placebo (P>0.05). The extract improved the quality of life measured by the SF-36 questionnaire significantly compared to the placebo and baseline (P=0.003 and P<0.001 respectively). Moreover, the extract lowered the rate of H. pylori infection determined by the urease test significantly compared to the placebo and baseline (P=0.001 and P<0.001 respectively). The extract did not significantly affect the complete blood count and liver and kidney function tests (P>0.05). The patients did not experience any adverse drug effect.

CONCLUSIONS

M. pulegium extract (genuine drug extract ratio: 19.4:1; extraction solvent: 70% v/v aqueous ethanol) 270mg three times daily taken for 2 months as adjunct to one famotidine 40mg tablet per day seems safe, improves dyspeptic symptoms and quality of life and eradicates H. pylori in functional dyspepsia patients.

Antioxidant capacity and phenolic content of two Algerian Mentha species M. rotundifolia (L.) Huds, M. pulegium L., extracted with different solvents

Background It is important to consider the optimum conditions and processing factors (like solvent type) influencing activity of plant antioxidants for utilization in food and biological systems. Methods The antioxidant capacity and phenolic content of two Mentha species, namely, Mentha pulegium L. (MP) and Mentha rotundifolia (L.) Huds (MR), were studied and six solvent systems were used. The total antioxidant capacity of the mint species extracts was evaluated using phosphomolybdenum method and the free radical-scavenging capacity by 2,2-diphenyl-1-picrylhydrazyl radical-scavenging assay. Results The efficiency of the used solvents to extract phenols from the two species varied considerably. The highest total phenolic content was obtained from methanol extract of MP (25.3±1.3 mg GAE/gdw) and total flavonoid content from methanol extract of MR (10.1±0.1 mg QE/gdw). High phenol content was significantly correlated with high antioxidant capacity. The methanol extracts showed the highest radical scavenging activity. All the extracts showed variable antioxidant capacity by the formation of phosphomolybdenum complex. Acetone extract of MP and methanol extract of MR exhibited marked reducing power in this method. Conclusions Our findings identified the appropriate solvent for extracting MP and MR phenolics which might provide a rich source of natural antioxidants.

Chemical content and antimicrobial properties of three different extracts of Mentha pulegium leaves from Mugla Region, Turkey

The extract of ethanol, methanol and DMSO of pennyroyal leaves from Mugla Region (Turkey) were tested for antimicrobial activity against eleven bacterial and one yeast strain by disc diffusion method. Among the extracts assayed, the methanol extract of pennyroyal leaves exhibited significant antimicrobial activity against Salmonella typhimurium and Staphylococcus aureus with 20 mm diameter inhibition zone. The DMSO extract of pennyroyal leaves displayed significant activity against S.aureus (19 mm) and Bacillus subtilis (21mm) showing inhibition zone of 19 mm and 21 mm diameter, while the ethanolic extract showed significant antimicrobial activity against S.aureus (17mm) and Klebsiella pneumoniae (20mm) inhibition zones.? On comparint the MIC value of ethanol, methanol and DMSO leaf extract, methanolic extract of pennyroyal presented best activity (MIC 8 mg ml-1) against S. typhimurium CCM 583 and S.aureus ATCC 6538/P. Analyses of GC/MS determined eleven compounds viz., neophytadiene (69.95%), Pulejon 7.85%, Pinane 4.81%, Bicyclo (3.1.1 Heptane 2.6.6.6 trimethyl) 4.68%. In conclusion, methanolic extracts of M. pulegium showed antimicrobial activity because of high neophytadiene content.

under drought stress

Effect of penconazole (PEN) treatment on drought-stressed Mentha pulegium L. plants was investigated. Six weeks after sowing, seedlings were grown under soil moisture corresponding to 100, 75, 50 and 25 % field capacity (FC) with or without PEN (15 mg l(-1)) for 4 weeks. Results showed that the seedlings at 75 % FC showed maximum growth and water supply lower than 75 % FC was the threshold of drought-initiated negative effects on seedling growth. Drought stress significantly induced proline and carbohydrate contents and the decreased chlorophyll, photosynthesis parameters, soluble proteins and ion accumulations. Exogenous PEN increased the growth parameters, pigments, photosynthesis and ion accumulations in drought stressed and unstressed plants, but the effects of PEN were more significant under water deficit conditions. PEN also reduced the negative effects of drought by osmotic balance and protein accumulations. Electrophoretic patterns indicated that PEN treatment increased the intensity of some protein bands with the molecular weights of 30 kDa in shoot and 31 kDa in roots, and several new protein bands with the molecular masses between 116 and 14 kDa appeared in leaves, shoots and roots. These results suggest that the PEN application can be a useful tool in alleviation of effects of drought stress in M. pulegium plants.

Nematicidal activity of essential oils and volatiles derived from Portuguese aromatic flora against the pinewood nematode, Bursaphelenchus xylophilus

Twenty seven essential oils, isolated from plants representing 11 families of Portuguese flora, were screened for their nematicidal activity against the pinewood nematode (PWN), Bursaphelenchus xylophilus. The essential oils were isolated by hydrodistillation and the volatiles by distillation-extraction, and both were analysed by GC and GC-MS. High nematicidal activity was achieved with essential oils from Chamaespartium tridentatum, Origanum vulgare, Satureja montana, Thymbra capitata, and Thymus caespititius. All of these essential oils had an estimated minimum inhibitory concentration ranging between 0.097 and 0.374 mg/ml and a lethal concentration necessary to kill 100% of the population (LC(100)) between 0.858 and 1.984 mg/ml. Good nematicidal activity was also obtained with the essential oil from Cymbopogon citratus. The dominant components of the effective oils were 1-octen-3-ol (9%), n-nonanal, and linalool (both 7%) in C. tridentatum, geranial (43%), neral (29%), and β-myrcene (25%) in C. citratus, carvacrol (36% and 39%), γ-terpinene (24% and 40%), and p-cymene (14% and 7%) in O. vulgare and S. montana, respectively, and carvacrol (75% and 65%, respectively) in T. capitata and T. caespititius. The other essential oils obtained from Portuguese flora yielded weak or no activity. Five essential oils with nematicidal activity against PWN are reported for the first time.