The Toxicological Safety Assessment of Heavy Metal Impurities (As, Pb, and Cd) in Mint Tea Infusions (Mentha piperita L.) Available in Polish Markets.

Mint tea (Mentha piperita L.) is one of the most widely consumed single infusion herbal teas (infusion) around the world; however, impurities and pollutants can pose a potential health risk to human health during tea drinking. The idea of this study was the comprehensive toxicological risk assessment (TRA) of three heavy metals (As, Pb, and Cd) in mint tea infusions (Mentha piperita L.; n = 17) available in Polish markets. We applied an inductively coupled plasma mass spectrometry (ICP-MS)-based methodology for the determination of the chosen heavy metals and designed a specific TRA approach. The first step in our TRA was the determination of the elements investigated (heavy metal impurity profile, µg/L of infusion). The second step was the estimation of the weekly intake (µg/L of infusion/week) based on the weekly consumption of tea. The third step was the estimation of the weekly intake per body weight (µg/L of infusion/week/bw) based on the weekly consumption of tea per adult person compared to the Provisional Tolerable Weekly Intake (PTWI) established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The level of investigated heavy metals occurs in all of the investigated mint tea infusions but at a relatively low level. The heavy metal profile indicated presence of As (0.36-1.254 µg/L), Pb (0.47-1.24 µg/L), and Cd (0.17-0.40 µg/L) in all the samples investigated. The basic analysis of the general content shows that As levels (mean = 0.70 µg/L) were very similar to the Pb levels (mean = 0.72 µg/L). The Cd content (mean = 0.21 µg/L) was approximately 3.5 times lower than the As and Pb levels. TRA provides satisfactory results for regulatory purposes. TRA for the elements investigated in the analyzed products indicated that there was no health hazard to consumers for weekly exposure. The results indicated that the levels of investigated elements in daily doses should not represent any health hazard to the consumer after drinking mini tea infusions from products available in Polish markets. This well-designed TRA methodology was useful and important for regulatory toxicology purposes.

The Control of Novel and Traditional Elemental Impurities: Ag, Au, Co, Cs, Li, Mo, Se, Sr, and V in Mint Tea Infusions (Peppermint, Mentha piperita L.) Available in Poland: A Health Risk Assessment.

The purpose of our studies is the evaluation of the health risks of the novel elemental impurities (Ag, Au, Co, Cs, Li, Mo, Se, Sr, and V) in mint tea infusions (Mentha piperita L.) available in Poland. For this purpose, we applied ICP-MS-based methodology for content analysis (elemental profile and µg/L of the infusion) and also the specific health risk assessment for a comprehensive assessment. Our strategy was based on weekly intake (µg/L of infusion/week) considering weekly tea consumption. Then, based on the weekly consumption of tea per adult, individuals were compared to the Temporary Tolerated Weekly Intake (PTWI) designated by the Joint FAO Expert Committee on Food Additives (JECFA), and the weekly consumption per body weight (µg/L of infusion/week/bw) was estimated. Daily exposure to Co in the tested products is in a range of 0.093-0.238 µg/day. In comparison, the established PDE (oral exposure) for Co by the ICH guideline (the ICH guideline Q3D (R1), 2019) is 50 µg/day. For lithium, PDE is approximately 560 µg/day and, in our study, the estimated daily exposure for Li in investigated products is in a range of 0.226-2.41 µg/day. Our studies found also low levels of Cs (in a range of 0.0598-0.195 µg/L), Mo (in a range of 0.663-3.261 µg/L), and Sr (0.223-65.842 µg/L) in infusions. For Molybdenum, the established PDE is approximately 3400 µg/day. There are no documents about Sr and Co in the Joint FAO/WHO Expert Committee on Food Additives (JECFA) database and the ICH guideline Q3D (R1). In the case of V, the established PDE is 120 µg/day, and the level of V in analyzed infusions is in a range of 0.284-0.702 µg/L. Silver and gold were present only in a few samples, and the estimated daily exposure for Ag is approximately 0.04575 µg/day for product A and approximately 0.1885 µg/day for product O, except for Au, which is in a range of 0.000356-0.114 µg/L. The estimated daily exposure for Ag is 167 µg/day and, for Au, it is in a range of 8.9 × 105-0.0285 µg/day. It can be concluded that levels of all investigated elements (novel and also traditional elemental impurities) in the daily dose should not threaten the consumer's health after consuming mint tea infusions.

Nano zinc elicited biochemical characterization, nutritional assessment, antioxidant enzymes and fatty acid profiling of rapeseed.

The use of nanomaterials in agriculture is a current need and could be helpful in overcoming food security risks. Brassica napus L. is the third most important crop for edible oil, having double low unsaturated fatty acids. In the present study, we investigated the effects of green synthesized Zn NPs on biochemical effects, antioxidant enzymes, nutritional quality parameters and on the fatty acid profile of rapeseed (B. napus). Plant-mediated synthesis of zinc nanoparticles (Zn NPs) was carried out using Mentha arvensis L. leaf extract followed by characterization through ultraviolet-visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-Ray (EDX), and X-Ray diffraction (XRD). NPs exhibited irregular shapes ranging in size from 30-70 nm and EDX analysis confirmed 96.08% of Zn in the sample. The investigated biochemical characterization (protein content, proline content, total soluble sugar (TSS), total flavonoid content (TFC), and total phenolic content (TPC) showed a substantial change on exposure to Zn NPs. A dose-dependent gradual increase was observed in the antioxidant enzymes, superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Oil and moisture contents dropped significantly from the control level in the rapeseed (B. napus) varieties. However, different trends in nutritional (Zn, Na+, K+) and fatty acid profiling of B. napus have been noted. This study demonstrates that Zn NPs have the potential to improve the biochemical, nutritional, antioxidant enzymes, and fatty acid profile of B. napus varieties.

Assessment of Mint, Basil, and Lavender Essential Oil Vapor-Phase in Antifungal Protection and Lemon Fruit Quality.

There is an increasing interest in developing natural methods to replace the current chemicals used for maintaining postharvest quality of citrus fruits. The essential oil antifungal activity of mint (MEO), basil (BEO), and lavender (LEO) acting as the vapor-phases was tested against Penicillium digitatum. The minimum doses with fungistatic and fungicidal effect, in vitro, acting as the vapor-phases, were set up. The minimum fungicidal dose was 300 µL for BEO and 350 µL LEO, while for MEO only minimal dose with fungistatic effect was reached. The IC50 values were calculated and used (v/v) for testing preservation of lemon fruits, in close space enriched in vapor oil. For this purpose, the following two independent in vivo experiments were carried out: experiment 1, inoculated lemons with P. digitatum stored without chemical treatments 7 days, at 22 ± 2 °C, at two concentrations (C1-IC50 equivalent; C2-half of C1); and experiment 2, the non-inoculated lemons kept under the same conditions and concentrations of EO vapor served to evaluate the lemon quality properties. The results showed that antifungal protective effect was provided in the order of LEO-C1 > BEO-C1 > MEO-C1 > BEO-C2 > MEO-C2 > LEO-C2. The quality indicators like weight loss, pH, and firmness were not negatively influenced.

Polyphenolic Profiling, Quantitative Assessment and Biological Activities of Tunisian Native Mentha rotundifolia (L.) Huds.

Phenolic profiling of ten plant samples of Mentha rotundifolia (L.) Huds. collected from different bioclimatic areas of Tunisia, was for the first time carried out by using a fast ultra-high-performance liquid chromatography (UHPLC)-high resolution tandem mass spectrometry (HRMS/MS) method on a Q Exactive platform equipped with an electrospray ionization (ESI) source. An intraspecific, interpopulation variability was evidenced and a total of 17 polyphenolic metabolites were identified and quantified by using the UHPLC-HRESIMS/MS method, here validated for specificity, linearity, limit of detection, limit of quantitation, accuracy and precision. The quantitative method resulted sensitive at the nM level and reliable for rapid polyphenol quantification in vegetal matrices. The metabolomic study allowed us to identify a new compound, named salvianolic acid W, which was isolated and characterized mainly by NMR and MS analysis. A statistical correlation of the phenolic composition with antioxidant and anti-acetylcholinesterase activities was provided.

Genotoxicity assessment of piperitenone oxide: An in vitro and in silico evaluation.

Piperitenone oxide, a natural flavouring agent also known as rotundifolone, has been studied for the genotoxicity assessment by an integrated in vitro and in silico experimental approach, including the bacterial reverse mutation assay, the micronucleus test, the comet assay and the computational prediction by Toxtree and VEGA tools. Under our experimental conditions, the monoterpene showed to induce both point mutations (i.e. frameshift, base-substitution and/or oxidative damage) and DNA damage (i.e. clastogenic or aneuploidic damage, or single-strand breaks). Computational prediction for piperitenone oxide agreed with the toxicological data, and highlighted the presence of the epoxide function and the α,ß-unsaturated carbonyl as possible structural alerts for DNA damage. However, improving the toxicological libraries for natural occurring compounds is required in order to favour the applicability of in silico models to the toxicological predictions. Further in vivo evaluations are strictly needed in order to evaluate the role of the bioavailability of the substance and the metabolic fate on its genotoxicity profile. To the best of our knowledge, these data represent the first evaluation of the genotoxicity for this flavour compound and suggest the need of further studies to assess the safety of piperitenone oxide as a flavouring agent.

Chemically characterized Mentha cardiaca L. essential oil as plant based preservative in view of efficacy against biodeteriorating fungi of dry fruits, aflatoxin secretion, lipid peroxidation and safety profile assessment.

The study reports Mentha cardiaca essential oil (EO) as plant based preservative against fungal and aflatoxin contamination of stored dry fruits. Mycoflora analysis of the dry fruits revealed Aspergillus favus LHP-PV-1 as the most aflatoxigenic isolate with highest Aflatoxin B1 content. M. cardiaca EO showed broad fungitoxic spectrum inhibiting the tested moulds contaminating dry fruits. It's minimum inhibitory concentration (MIC), minimum aflatoxin inhibitory concentration (MAIC) and minimum fungicidal concentration (MFC) against A. favus LHP-PV-1 were recorded to be 1.25, 1.0 and 2.25 µL/mL respectively. The EO caused decrease in ergosterol content and enhanced leakage of Ca2+, K+ and Mg2+ ions from treated fungal cells, depicting fungal plasma membrane as the site of antifungal action. The EO showed promising DPPH free radical scavenging activity (IC50 value:15.89 µL/mL) and favourable safety profile with LD50 value (7133.70 mg/kg body wt.) when estimated through acute oral toxicity on mice. Carvone (61.62%) was recorded as the major component of the oil during chemical characterisation through GC-MS. Based on strong antifungal, antiaflatoxigenic and antioxidant potential, the chemically characterised M. cardiaca EO may be recommended as safe plant based preservative and shelf life enhancer of food items. This is the first report on antifungal and antiaflatoxigenic activity of M. cardiaca EO.

Assessment of mint (Mentha spp) species for large-scale production of plantlets by micropropagation / Avaliação de espécies de menta (Mentha spp) para a produção de mudas em larga escala por micropropagação

Species of the genus Mentha produce essential oils which are widely used in pharmaceutical and cosmetic industries. Current study evaluates the potential for in vitro propagation and estimates mass production of plantlets of Mentha species. Nine species (M. piperita, M. suaveolens, M. canadensis, M. longiflora, M. aquatica, M. arvensis, Mentha x gracilis, M. gracilis and M. spicata) were propagated with five successive 30-day subcultures in MS medium supplemented with NAA (0.05 µM) and BAP (4.4 µM). Shoots were rooted in MS with IBA, IAA or NAA (0.0; 0.25; 0.5; 2.5 or 5.0 µM). The rooted plantlets were finally acclimatized in a greenhouse. Studied species increased in multiplication rates between 4.2 and 9.0-fold per month. M. piperita, M. longiflora, M. arvensis, M. x gracilis and M. gracilis showed the greatest potential for plantlet production since the estimated production varied between 6,000 and 27,000 plantlets after five 30-days subcultures. The addition of auxin to the medium did not influence root induction. However, IAA at a concentration of 5 µM provided the best results for root length and fresh weight, with averages 11.1 cm and 0.16 g, respectively. Survival of plantlets reached 100% during the greenhouse acclimatization process.

Espécies do gênero Mentha produzem óleos essenciais largamente usados na indústria farmacêutica e de cosméticos. O estudo avaliou o potencial de propagação in vitro e estimou a produção de mudas de espécies de menta. Nove espécies (M. piperita, M. suaveolens, M. canadensis, M. longiflora, M. aquatica, M. arvensis, Mentha x gracilis, M. gracilis e M. spicata) foram propagadas por até cinco sucessivos subcultivos de 30 dias em meio de MS adicionado de ANA (0,05 µM) e BAP (4,4 µM). Os brotos foram enraizados em meio de MS com AIB, AIA ou ANA (0,0; 0,25; 0,5; 2,5 ou 5,0 µM). Finalmente, as mudas foram aclimatizadas em casa de vegetação. As espécies estudadas apresentaram aumentos nas taxas de multiplicação, variando entre 4,2 e 9,0 vezes por mês. M. piperita, M. longiflora, M. arvensis, M. x gracilis e M. gracilis mostraram os melhores potenciais para propagação, uma vez que a produção variou entre 6.000 e 27.000 mudas após cinco subcultivos de 30 dias. A adição de auxina no meio não influenciou a indução de raízes. Entretanto, o AIA na concentração de 5 µM promoveu os melhores resultados quanto ao comprimento e massa fresca das raízes, com médias de 11,1 cm e 0,16 g, respectivamente. No processo de aclimatização houve 100% de sobrevivência das mudas.

Impact assessment of mercury accumulation and biochemical and molecular response of Mentha arvensis: a potential hyperaccumulator plant.

The present study was focused on examining the effect of Hg oxidative stress induced physiochemical and genetic changes in M. arvensis seedlings. The growth rate of Hg treated seedlings was decreased to 56.1% and 41.5% in roots and shoots, respectively, compared to the control. Accumulation of Hg level in both roots and shoots was increased with increasing the concentration of Hg. Superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities were found to be increased with increasing the Hg concentration up to 20 mg/L; however, it was decreased at 25 mg/L Hg concentration. The POX enzyme activity was positively correlated with Hg dose. The changes occurring in the random amplification of ploymorphic DNA (RAPD) profiles generated from Hg treated seedlings included variations in band intensity, disappearance of bands, and appearance of new bands compared with the control seedlings. It was concluded that DNA polymorphisms observed with RAPD profile could be used as molecular marker for the evaluation of heavy metal induced genotoxic effects in plant species. The present results strongly suggested that Mentha arvensis could be used as a potential phytoremediator plant in mercury polluted environment.

Assessment of wild mint from Tunceli as source of bioactive compounds, and its antioxidant Activity.

The types of wild mint (Mentha spicata L.) were sampled from different geographical regions in Tunceli (Turkey) in order to find out their vitamin, mineral, phenolic contents and their antioxidant properties. The total phenol varied from 77.7±0.242 to 52.34±0.351 mg of GAEs/g of dry mint. The highest radical effect of scavenging was observed in Mazgirt parting of the ways 7.5 km with 6.17±0.245 mg/mL. The highest reducing power and metal chelating were observed in the mint from Cicekli parting of the ways 6.5 km Demirkapi. Among the various macronutrients which were estimated in the plant samples, potassium was presented in the highest quantity followed by calcium and phosphate. Although rutin and resveratrol were not determined in any samples, kaempferol and catechin levels were found out in almost all samples. The concentrations of vitamin A ranged between 42,14±5.70 and 13.61±3.00 (mg/kg dry weight). These results show that plants of mint are quite rich in phenolic compounds, and these have been appeared to have antioxidant activity, which agrees with this work, since the extract showed a higher content of phenolic compounds and higher antioxidant activity and mint may be considered as a natural alternative source for food, pharmacology and medicine sectors.

Avaliação da atividade antimicrobiana e antioxidante das espécies Plectranthus amboinicus (Lour.) e Mentha x villosa (Huds. ) / Assessment of antimicrobial and antioxidant activity and toxicity of the species Coleus amboinicus (Lour.) and Mentha x Villosa (Huds. )

O uso de plantas medicinais com potencial terapêutico tem motivado a realização de estudos através de ensaios experimentais que visam fornecer informações úteis e de extrema importância. Assim o presente trabalho objetivou avaliar a atividade antimicrobiana e antioxidante das espécies de Coleus amboinicus (Lour.) e Mentha x villosa (Huds). A atividade antimicrobiana foi avaliada pelo método de difusão em disco, cepas bacterianas padronizadas Gram negativas Escherichia coli (ATCC 25922 e ATCC 35218)), cepas Gram positivas Staphylococcus aureus (ATCC 25923) e S. aureus ATCC27853), assim como fungos padrões de Cryptococcus neoformans (pertencentes à coleção de microrganismos do CESMAC). Como controle positivo foi usado o imipenem e fluconazol e como controle negativo um disco com etanol absoluto. A determinação do potencial antioxidante foi realizada utilizando os métodos DPPH, FTC e determinação de compostos fenólicos. Os extratos etanólicos de C. amboinicus e M. x villosa apresentaram excelentes resultados tanto relacionado à atividade antimicrobiana quanto à antioxidante. Nossos resultados mostram a potencialidade das plantas analisadas na prevenção e no combate de doenças...

The popular use of medicinal plants with therapeutic potential has motivated experimental studies aimed at providing useful information of the utmost importance. Thus, in the present study, the antimicrobial and antioxidant activities of the species Coleus amboinicus(Lour.) and Mentha x villosa (Huds.) were assessed. Antimicrobial activity was determined by the disk diffusion method with standard Gram-negative (Escherichia coli: ATCC 25922 and ATCC 35218) and Gram-positive (Staphylococcus aureus: ATCC 25923and ATCC 27853) bacterial strains, as well as a standard strain of the fungus Cryptococcus neoformans (belonging to the CESMAC collection of microorganisms). Discs with imipenen and fluconazole were used as positive controls and a disc with absolute ethanol as a negative control. The antioxidant power was assayed by the DPPH and FTC methods and determination of total phenolic compound contents. The ethanolic extracts of C. and M. amboinicus x villosa showed excellent results with regard to both antimicrobial and antioxidant activities. Our results show the potential of these plants for preventing and fighting disease...

Assessment of trace element concentrations in soil and plants from cropland irrigated with wastewater.

Samples of soil and food plants were collected from wastewater-irrigated fields in the vicinity of Gaziantep, in southeast Turkey, and analyzed for several trace elements (TEs). The concentrations of Co, Mo and Zn in edible portions of corn, mint and vegetables (eggplant, pepper and tomato) were 0.03-0.66, 0.1-3.2 and 8-148 mg kg⁻¹, respectively. In the edible portions of corn and mint, Cd, Cr, Cu, Ni and Pb concentrations in all samples were <0.01-0.05, 2.0-5.5, 6-47, 0.6-6.7 and 0.2-3.5 mg kg⁻¹, respectively. No single plant species had consistently high concentrations of all metals. For example, corn had the highest concentration of Zn (89 mg kg⁻¹), but the lowest concentration of Cd (<0.01 mg kg⁻¹). The maximum concentrations of some TEs in some crop samples, as well as soil samples, exceeded certain threshold values set in Turkey and other countries. For some TEs there was little difference between wastewater-irrigated and control soil concentrations. Transfer factors (TFs; plant concentration/soil concentration) were high for Cu, Zn and Mo, in comparison with the other TEs (Cd, Co, Cr, Ni and Pb). Higher uptake of certain metals may be associated with the dominant form of the element in the soil matrix. The uptake of chemicals to plant tissues is influenced by the chemical and physical characteristics of the soil and species-specific factors. Although the geochemistry of the region plays a significant role in the levels of TEs in soil and plants, bioaccumulation of metals and subsequent toxicity to plants and animals can be exacerbated by higher environmental concentrations caused by wastewater irrigation and other anthropogenic factors.

Objective assessment of olfactory function using functional magnetic resonance imaging.

OBJECTIVE: To show the results of a device that generates automated olfactory stimuli suitable for functional magnetic resonance imaging (fMRI) experiments. MATERIAL AND METHODS: Ten normal volunteers, 5 women and 5 men, were studied. The system allows the programming of several sequences, providing the capability to synchronise the onset of odour presentation with acquisition by a trigger signal of the MRI scanner. The olfactometer is a device that allows selection of the odour, the event paradigm, the time of stimuli and the odour concentration. The paradigm used during fMRI scanning consisted of 15-s blocks. The odorant event took 2s with butanol, mint and coffee. RESULTS: We observed olfactory activity in the olfactory bulb, entorhinal cortex (4%), amygdala (2.5%) and temporo-parietal cortex, especially in the areas related to emotional integration. CONCLUSIONS: The device has demonstrated its effectiveness in stimulating olfactory areas and its capacity to adapt to fMRI equipment.

Protective effects of Mentha haplocalyx ethanol extract (MH) in a mouse model of allergic asthma.

Mentha haplocalyx Briq., a commonly used herb in traditional Oriental medicine, has a variety of known pharmacological properties. However, neither the protective effects of Mentha haplocalyx ethanol extract (MH) against inflammation of the airway in an asthmatic model nor the mechanisms involved, have previously been reported. In the present study, an ovalbumin (OVA)-induced mouse model of allergic asthma was used to investigate whether MH was effective against the disease through regulation of airway inflammation. The MH treatment significantly inhibited increases in immunoglobulin (Ig) E and T-helper 2 (Th2)-type cytokines such as IL-4 and IL-5 in bronchoalveolar lavage fluid (BALF) and lung tissue. Inflammatory cell infiltration of the airway in mice treated with MH was effectively alleviated when compared with infiltration seen in the OVA-induced group. These data indicated that decreased cytokine levels are the result of the decreased number of invaded leukocytes. Also, the generation of reactive oxygen species (ROS) in BALF was diminished by MH treatment. Taken together, these findings indicate that the administration of MH may have potential therapeutic value in the treatment of inflammatory disease.

A rapid LC/MS/MS method for the analysis of nonvolatile antiinflammatory agents from Mentha spp.

UNLABELLED: Mints (Mentha spp.), aromatic crops grown largely for their essential oils, also are rich sources of nonvolatile antiinflammatory agents. Identification and quantitation of the constituents responsible for their antiinflammatory activity is challenging owing to the lack of suitable chromatographic methodology. In the present research, the simultaneous quantitation of antiinflammatory constituents rosmarinic acid, oleanolic acid, and ursolic acid in mints was attained by using a unique tandem HPLC column system coupled with an electrospray ionization mass detection (MRM mode). The ion mode optimization for rosmarinic acid under negative and triterpenoid acids under positive was achieved by setting 2 time segments in a single run where the polarity mode was switched from negative (0 to 10 min) to positive (10 to 40 min). For the investigated concentration ranges of antiinflammatory agents in mints, good linearities (r² ≥ 0.998) were obtained for each calibration curve. Validation of precision and accuracy for this method showed that intra- and inter-day repeatabilities for all analytes were less than 5.51%, and the recoveries varied from 97.8% to 99.3%. The developed LC/MS/MS assay provides a suitable quality control method for the determination of antiinflammatory constituents in Mentha spp. There is a wide range of diversity in the natural product composition for these acids across the Mentha germplasm collection evaluated. The presence of these antiinflammatory acids in post-distilled mints shows that value-added nutraceutical enriched products can be developed with proper processing and recovery systems in addition to the distillation and capture of the valuable volatile essential oils. PRACTICAL APPLICATION: Results from this research would benefit both commercial farmers growing mint for essential oil and those in the food industry where value-added phytopharmaceutical enriched products can be developed with proper processing, quality control, and recovery systems during mint essential oil distillation.

Solvent-free microwave extraction of essential oil from aromatic herbs: comparison with conventional hydro-distillation.

Solvent-free microwave extraction (SFME) is a combination of microwave heating and dry distillation, performed at atmospheric pressure without added any solvent or water. Isolation and concentration of volatile compounds are performed by a single stage. SFME has been compared with a conventional technique, hydro-distillation (HD), for the extraction of essential oil from three aromatic herbs: basil (Ocimum basilicum L.), garden mint (Mentha crispa L.), and thyme (Thymus vulgaris L.). The essential oils extracted by SFME for 30min were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained by conventional hydro-distillation for 4.5 h. The SFME method yields an essential oil with higher amounts of more valuable oxygenated compounds, and allows substantial savings of costs, in terms of time, energy and plant material. SFME is a green technology and appears as a good alternative for the extraction of essential oils from aromatic plants.

Assessment of reversible contraceptive efficacy of methanol extract of Mentha arvensis L. leaves in male albino mice.

The present study was undertaken to assess the reversible contraceptive efficacy of methanolic extract of Mentha arvensis leaves. Aqueous solution of the extract (10 mg per day per mouse) when administered orally to male mice of proven fertility for 20, 40 and 60 days caused inhibition of fertility while maintaining their normal sexual behaviour. With the increase in treatment duration, there occurred a corresponding decrease in the mean weight of testis and accessory organs of reproduction. Sperm concentration, motility and viability in the cauda epididymis were also decreased. Spermatozoa with coiled tails also appeared in the epididymal smear. However, all the induced effects returned to normalcy within 30 days following withdrawal of 60-day treatment. Oral administration of the extract also did not affect the body weight of the mice and their blood cells count, packed cell volume, haemoglobin and blood/serum biochemistry.

Final report on the safety assessment of Mentha Piperita (Peppermint) Oil, Mentha Piperita (Peppermint) Leaf Extract, Mentha Piperita (Peppermint) Leaf, and Mentha Piperita (Peppermint) Leaf Water.

Mentha Piperita (Peppermint) Oil, Mentha Piperita (Peppermint) Leaf Extract, Mentha Piperita (Peppermint) Leaf, Mentha Piperita (Peppermint) Leaf Water are obtained from the Mentha piperita plant. The oil is currently used in cosmetic formulations as a fragrance component, but previously had been also described as a denaturant. The extract and leaves are described as biological additives, but only the extract is reported to be used. Peppermint Water is described as a flavoring agent or fragrance component, but is not currently in use. Peppermint Oil is used at a concentration of < or = 3% in rinse-off formulations and < or = 0.2% in leave-on formulations. Peppermint Oil is composed primarily of menthol and menthone. Other possible constituents include pulegone, menthofuran, and limone. Most of the safety test data concern Peppermint Oil. The oil is considered to present the "worst case scenario" because of its many constituents, so data on the oil were considered relevant to the entire group of ingredients. Peppermint Oil was minimally toxic in acute oral studies. Short-term and sub-chronic oral studies reported cystlike lesions in the cerebellum in rats that were given doses of Peppermint Oil containing pulegone, pulegone alone, or large amounts (>200 mg/kg/day) of menthone. Pulegone is also a recognized hepatotoxin. Repeated intradermal dosing with Peppermint Oil produced moderate and severe reactions in rabbits, although Peppermint Oil did not appear to be phototoxic. Peppermint Oil was negative in the Ames test and a mouse lymphoma mutagenesis assay but gave equivocal results in a Chinese hamster fibroblast cell chromosome aberration assay. In a carcinogenicity study of toothpaste and its components, no apparent differences were noted between mice treated with Peppermint Oil and those treated with the toothpaste base. Isolated clinical cases of irritation and/or sensitization to Peppermint Oil and/or its constituents have been reported, but Peppermint Oil (8%) was not a sensitizer when tested using a maximization protocol. It was expected that dermal absorption of Peppermint Oil would be rapid, following that of menthol, a major component, but in no case would be greater than absorption through the gastrointestinal tract. Because of the toxicity of pulegone, the safe concentration of this constituent was limited to < or = 1%. This concentration was achievable both by controlling the time of harvest and processing technique. There is evidence that menthol can enhance penetration of other agents. Formulators were cautioned that this enhanced penetration can affect the use of other ingredients whose safety assessment was based on their lack of absorption. With the limitation that the concentration of pulegone in these ingredients should not exceed 1%, it was concluded that Mentha Piperita (Peppermint) Oil, Mentha Piperita (Peppermint) Extract, Mentha Piperita (Peppermint) Leaves, Mentha Piperita (Peppermint) Water are safe as used in cosmetic formulations.