Chemical Composition and Antimicrobial and Antioxidant Activities of Mentha (longifolia L. and viridis) Essential Oils

Rapid quantification of clove (Syzygium aromaticum) and spearmint (Mentha spicata) essential oils encapsulated in a complex organic matrix using an ATR-FTIR spectroscopic method

Essential oils (EOs) are often encapsulated in various and complex matrices to protect them against potential degradation or to control their release. To achieve an optimum use in food products, their rapid and precise quantification after encapsulation and storage is required. Hence, a rapid ATR-FTIR method was developed and tested with two encapsulated essential oils (EOs): clove (Syzygium aromaticum) and spearmint (Mentha spicata);. Despite, the complexity of the matrix, this method coupled with univariate or multivariate regression models exhibited high potential for global quantification of the two encapsulated EOs. For clove EO, in relation to the major presence of eugenol and eugenol acetate, an analysis based on a unique band (1514 cm^-1) was sufficient to obtain a good prediction with RMSEP value of 0.0173 g of EO per g of matrix. For spearmint oil which is characterized by numerous terpenoid compound, three bands (799, 885, and 1680–1676 cm^-1) were suitable for a good prediction with RMSEP value of 0.0133. ATR-FTIR method was compared with a reference gas chromatography FID quantitative method in an EO release experiment and its efficiency was evaluated through modeling by the Avrami equation. Beside time saving, the ATR-FTIR method was also capable of monitoring the EO profile. This method could be easily adapted as a routine analysis in the EOs industry as quality control.

Prospective of Essential Oils of the Genus Mentha as Biopesticides: A Review

Mentha is a genus from the family Lamiaceae, whose essential oils has long been used in various forms such as in management of plant pathogens and insect pests, in traditional medicine as well as in culinary and cosmetics. Its major chemical components such as menthol, carvone have now been successfully commercialized in the industry as antimicrobials/insecticidal agents. Current review focuses on chemical composition of essential oils of some Mentha species from different geographical regions with their insecticidal (repellent, antifeedant, and ovicidal) and antimicrobial efficacies against bacterial, fungal plant pathogens and insects of stored products. Reports of the researchers on chemical analysis of essential oils of Mentha species revealed that most of the oils being rich in pulegone, menthon, menthol, carvone, 1, 8-cineole, limonene and β-caryophyllene. Reviewed literature revealed that, essential oils from different Mentha species possess potential antimicrobial activity against plant pathogens and have insecticidal activity against stored product insects. Thus, antimicrobial and insecticidal properties of essential oils of Mentha species offer the prospect of using them as natural pesticides with a commercial value, having social acceptance due to its sustainability and being environment friendly.

Plants of Genus Mentha: From Farm to Food Factory

Genus Mentha, a member of Lamiaceae family, encompasses a series of species used on an industrial scale and with a well-described and developed culture process. Extracts of this genus are traditionally used as foods and are highly valued due to the presence of significant amounts of antioxidant phenolic compounds. Many essential oil chemotypes show distinct aromatic flavor conferred by different terpene proportions. Mint extracts and their derived essential oils exert notable effects against a broad spectrum of bacteria, fungi or yeasts, tested both in vitro or in various food matrices. Their chemical compositions are well-known, which suggest and even prompt their safe use. In this review, genus Mentha plant cultivation, phytochemical analysis and even antimicrobial activity are carefully described. Also, in consideration of its natural origin, antioxidant and antimicrobial properties, a special emphasis was given to mint-derived products as an interesting alternative to artificial preservatives towards establishing a wide range of applications for shelf-life extension of food ingredients and even foodstuffs. Mentha cultivation techniques markedly influence its phytochemical composition. Both extracts and essential oils display a broad spectrum of activity, closely related to its phytochemical composition. Therefore, industrial implementation of genus Mentha depends on its efficacy, safety and neutral taste.

Effective antioxidant, antimicrobial and anticancer activities of essential oils of horticultural aromatic crops in northern Egypt

Background

Identifying ornamental plants as new natural antioxidant and antimicrobial sources is always of great importance for the ornamental and horticultural industries.

Methods

The antimicrobial activities of leaves and fruits peel essential oils of twelve ornamental and horticultural crops were determined by screening against wide spectrum of fungi and bacteria, and their respective in vitro antioxidant capacity was evaluated. Furthermore, the anticancer activities against several cancer cells, and one normal human cell line (HEK-293) were examined.

Results

Origanum vulgare L. essential oil showed the best antioxidant, antibacterial and anticancer activities compared to screened crops by means of the DPPH and linoleic acid assays for antioxidants, MIC and MBC values for antibacterial activities and IC₅₀ for antiproliferative activities. Such important activities in O. vulgare was attributed to high pulegone ratio (77.45%) as revealed by the GC/MS assay. Rosmarinus officinallis L. essential oil showed the highest antifungal activities by means of lowest MIC and MFC values which might be attributed to 1, 8-cineole (19.60%), camphor (17.01%) and α-pinene (15.12%).

Conclusion

We suggest that oxygenated monoterpenes (i.e. linalool, terpinen-4-ol and pulegone) and monoterpene hydrocarbons play an important role in the essential oil antioxidant, antibacterial, antifungal and anticancer activities of diverse Egyptian ornamental and horticultural crops. Some species showed bioactivities similar to standards compounds and might be suitable for pharmaceutical and food industries.

Terpenes from Forests and Human Health

Forest bathing has beneficial effects on human health via showering of forest aerosols as well as physical relaxation. Terpenes that consist of multiple isoprene units are the largest class of organic compounds produced by various plants, and one of the major components of forest aerosols. Traditionally, terpene-containing plant oil has been used to treat various diseases without knowing the exact functions or the mechanisms of action of the individual bioactive compounds. This review categorizes various terpenes easily obtained from forests according to their anti-inflammatory, anti-tumorigenic, or neuroprotective activities. Moreover, potential action mechanisms of the individual terpenes and their effects on such processes, which are described in various in vivo and in vitro systems, are discussed. In conclusion, the studies that show the biological effectiveness of terpenes support the benefits of forest bathing and propose a potential use of terpenes as chemotherapeutic agents for treating various human diseases.

Calamintha nepeta (L.) Savi and its Main Essential Oil Constituent Pulegone: Biological Activities and Chemistry

Medicinal plants play an important role in the treatment of a wide range of diseases, even if their chemical constituents are not always completely recognized. Observations on their use and efficacy significantly contribute to the disclosure of their therapeutic properties. Calamintha nepeta (L.) Savi is an aromatic herb with a mint-oregano flavor, used in the Mediterranean areas as a traditional medicine. It has an extensive range of biological activities, including antimicrobial, antioxidant and anti-inflammatory, as well as anti-ulcer and insecticidal properties. This study aims to review the scientific findings and research reported to date on Calamintha nepeta (L.) Savi that prove many of the remarkable various biological actions, effects and some uses of this species as a source of bioactive natural compounds. On the other hand, pulegone, the major chemical constituent of Calamintha nepeta (L.) Savi essential oil, has been reported to exhibit numerous bioactivities in cells and animals. Thus, this integrated overview also surveys and interprets the present knowledge of chemistry and analysis of this oxygenated monoterpene, as well as its beneficial bioactivities. Areas for future research are suggested.

A Comparative Analysis of the Chemical Composition, Anti-Inflammatory, and Antinociceptive Effects of the Essential Oils from Three Species of Mentha Cultivated in Romania

This work was aimed at correlating the chemotype of three Mentha species cultivated in Romania with an in vivo study of the anti-inflammatory and antinociceptive effects of essential oils. The selected species were Mentha piperita L. var. pallescens (white peppermint), Mentha spicata L. subsp. crispata (spearmint), and Mentha suaveolens Ehrh. (pineapple mint). Qualitative and quantitative analysis of the essential oils isolated from the selected Mentha species was performed by gas chromatography coupled with mass spectrometry (GC-MS). The anti-inflammatory activity of the essential oils was determined by the rat paw edema test induced by λ-carrageenan. The antinociceptive effect of the essential oils was evaluated by the writhing test in mice, using 1% (v/v) acetic acid solution administered intraperitonealy and by the hot plate test in mice. The results showed a menthol chemotype for M. piperita pallescens, a carvone chemotype for M. spicata, and a piperitenone oxide chemotype for M. suaveolens. The essential oil from M. spicata L. (EOMSP) produced statistically significant and dose-dependent anti-inflammatory and antinociceptive effects.

Ethnomedicinal uses of plants in the treatment of paediatric geohelminth infections in Kalat district of Northern Balochistan, Pakistan

ETHNOPHARMACOLOGICAL RELEVANCE

Infection by intestinal parasitic worms (soil-transmitted helminths or geohelminths) is prevalent in many parts of the world, and poses a particular health risk to children. This paper presents findings from a preliminary study with the primary aim to document indigenous knowledge about the use of herbal medicines in the treatment of intestinal worm infections in children among the local communities of Kalat district of northern Balochistan, Pakistan.

MATERIALS AND METHODS

Ethnomedicinal data were collected through a triangulation approach, that included participant-observation and rapid appraisal methods. Prior-informed consent (PIC) was obtained from participants before conducting structured and semi-structured interviews and delivering an open ended questionnaire. A total of 94 participants, including 28 men (of whom 7 were traditional healers), and 66 women of four different age groups were interviewed. Results were analyzed using quantitative indices of Use Value citations (UVC) and Disease-Consensus Index (DCI).

RESULTS

Fewer men than women agreed to be interviewed, thus overall women in the area appeared to have more ethnomedicinal knowledge. The majority of study participants belonged to the older age group (>55 years). A total of 49 plant species, belonging to 47 genera, distributed in 30 families were reported. The families Asteraceae and Lamiaceae were most frequently represented, with four species each. Trees were the most common life form, with seeds the most frequently cited plant part used (29%). Nearly a third (31%) of plant-based remedies reported in the treatment of intestinal worms were administered as a decoction. The highest UVC and DCI was reported for the species Ferula assa-foetida sL. (UVC 0.51, DCI 0.46).

CONCLUSIONS

This study provides previously unreported data on the use of medicinal plants in the treatment of geohelminth infections in children of Kalat. Eight species, Acacia modesta Wall., Asparagus capitatus Baker, Microcephala lamellata (Bunge) Pobed., Nepeta praetervisa Rech.f., Plantago ciliata Desf., Pistacia atlantica Desf., Seriphidium quettense (Podlech) Y.R.Ling and Thymus linearis Benth. are reported here as anthelmintics for the first time. Detailed studies on the anthelmintic activity of chemical constituents of these species are lacking from existing literature. Further phytochemical, pharmacological and toxicity studies are required in order to evaluate the efficacy and safety of these newly reported anthelmintic species. These plants may provide a source of novel anthelmintic drug leads, which are urgently required due to the problem of global anthelmintic resistance.

Legionella pneumophila: The Paradox of a Highly Sensitive Opportunistic Waterborne Pathogen Able to Persist in the Environment

Legionella pneumophila, the major causative agent of Legionnaires’ disease, is found in freshwater environments in close association with free-living amoebae and multispecies biofilms, leading to persistence, spread, biocide resistance, and elevated virulence of the bacterium. Indeed, legionellosis outbreaks are mainly due to the ability of this bacterium to colonize and persist in water facilities, despite harsh physical and chemical treatments. However, these treatments are not totally efficient and, after a lag period, L. pneumophila may be able to quickly re-colonize these systems. Several natural compounds (biosurfactants, antimicrobial peptides…) with anti-Legionella properties have recently been described in the literature, highlighting their specific activities against this pathogen. In this review, we first consider this hallmark of Legionella to resist killing, in regard to its biofilm or host-associated life style. Then, we focus more accurately on natural anti-Legionella molecules described so far, which could provide new eco-friendly and alternative ways to struggle against this important pathogen in plumbing.

Review of Scientific Evidence of Medicinal Convoy Plants in Traditional Persian Medicine

One concept used in traditional Persian medicine (TPM) for multidrug therapy is that of the convoy drug (Mobadregh). According to TPM texts, convoy drugs are substances (or drugs), which facilitate the access of drugs or foods to the whole body or to specific organs. This study reviewed some convoy drugs presented in TPM, their biological effects, and their probable interactions with main drugs, considering the increased absorption through inhibition of P-glycoprotein (P-gp) efflux function, bioavailability-enhancing effects, and decreased metabolism of the main drug using electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar in November and December, 2013. Recent studies have proven the beneficial effects of Crocus sativus L. (saffron) and camphor on the heart and brain, the cerebral therapeutic effects of Asarum europaeum (hazelwort), the hepatoprotective effects of Cichorium intybus (chicory), and Apium graveolens (celery) seeds, and the diuretic effects of Cinnamomum zeylanicum (cinnamon), and Cucumis melo (melon) seeds. The effects of vinegar in targeting the liver and brain have also been demonstrated. An evaluation of the results demonstrated that the suggested convoy drugs, including Piper nigrum (black pepper), Piper longum (long pepper), red wine, Camellia sinensis (tea), hazelwort, Mentha longifolia (pennyroyal), Anethum graveolens (dill), Foeniculum vulgare (fennel), cinnamon, and Sassafras albidum (sassafras) can increase the bioavailability of coadministered drugs by inhibition of P-gp or cytochrome P450s (CYP450s) or both of them. This evidence could be a good basis for the use of these agents as convoys in TPM.

Coatings comprising chitosan and Mentha piperita L. or Mentha × villosa Huds essential oils to prevent common postharvest mold infections and maintain the quality of cherry tomato fruit

In this study, we evaluated the efficacy of coatings comprising shrimp chitosan (CHI) and Mentha piperita L. (MPEO) or Mentha × villosa Huds (MVEO) essential oils to control mold infections caused by Aspergillus niger, Botrytis cinerea, Penicillium expansum and Rhizopus stolonifer in cherry tomato fruits (Solanum lycopersicum L.) during storage at room temperature (25°C for 12 days) and low temperature (12°C for 24 days). The effects of the coatings on the physicochemical and sensory characteristics of cherry tomato fruits during storage were also assessed. The minimum inhibitory concentration (MIC) of CHI against all test fungi was 8 mg/mL, whereas the MIC for both MPEO and MVEO was 5 μL/mL. Combinations of CHI at 4 mg/mL and MPEO or MVEO at 2.5 or 1.25 μL/mL strongly inhibited the mycelial growth and spore germination of target fungi. The coatings comprising CHI and MPEO or CHI and MVEO at the different tested concentrations delayed the growth of decay-causing fungi in artificially contaminated tomato fruit during storage at either room temperature or low temperature. The assayed coatings preserved the quality of cherry tomato fruit during storage, in terms of physicochemical and sensory attributes. These results indicate that coatings comprising CHI and MPEO or CHI and MVEO represent promising postharvest treatments to prevent common postharvest mold infections in cherry tomato fruit during storage without affecting the quality of the fruit.

Mentha spicata Essential Oil: Chemical Composition, Antioxidant and Antibacterial Activities against Planktonic and Biofilm Cultures of Vibrio spp. Strains

Chemical composition, antioxidant and anti-Vibrio spp. activities of the essential oil isolated from the aerial parts of Mentha spicata L. (spearmint) are investigated in the present study. The effect of the essential oil on Vibrio spp. biofilm inhibition and eradication was tested using the XTT assay. A total of 63 chemical constituents were identified in spearmint oil using GC/MS, constituting 99.9% of the total identified compounds. The main components were carvone (40.8% ± 1.23%) and limonene (20.8% ± 1.12%). The antimicrobial activity against 30 Vibrio spp. strains (16 species) was evaluated by disc diffusion and microdilution assays. All microorganisms were strongly affected, indicating an appreciable antimicrobial potential of the oil. Moreover, the investigated oil exhibited high antioxidant potency, as assessed by four different tests in comparison with BHT. The ability of the oil, belonging to the carvone chemotype, to inhibit or reduce Vibrio spp. biofilm warrants further investigation to explore the use of natural products in antibiofilm adhesion and reinforce the possibility of its use in the pharmaceutical or food industry as a natural antibiotic and seafood preservative against Vibrio contamination.

Screening for antibacterial activity of some Turkish plants against fish pathogens: a possible alternative in the treatment of bacterial infections

The antibacterial activity of ethanolic and aqueous crude extracts from 36 plants in Turkey, including seven endemic species, against fish pathogens was studied using the disc diffusion assay. The extract that was most active against all microbial strains, except Aeromonas salmonicida, was that of Dorycnium pentaphyllum. Some of the extracts also showed a very broad spectrum of potent antimicrobial activity. The extract of Anemone nemorosa showed the highest antimicrobial activity against Vibrio anguillarum. V. anguillarum, a Gram-negative bacterium, appeared to be the most susceptible to the plant extracts used in this experiment. To the best of our knowledge, this is the first report on the antimicrobial activity of 11 of the studied plants. The preliminary screening assay indicated that some of the Turkish plants with antibacterial properties may offer alternative therapeutic agents against bacterial infections in aquaculture industry.

Pharmacological and therapeutic effects of Mentha Longifolia L. and its main constituent, menthol

Mentha longifolia (wild mint) is a popular folk remedy. Some parts of this plant have been used in traditional medicine of Iran and other countries. Many studies have shown various pharmacological and therapeutic effects of the plant. Our aim in preparing this study was to review the traditional uses of M. longifolia together with the pharmacological and therapeutic effects of its entire extract and major compounds. Mentha longifolia is an herb with a wide range of pharmacological properties such as antimicrobial, gastrointestinal, and nervous system effects. Pulegone is the main compound of the plant responsible for most of its pharmacological effects followed by menthone, isomenthone, menthol, 1, 8-cineole, borneol, and piperitenone. Moreover, the plant may dose-dependently exert toxic effects in different systems of the body. Based on the review of various studies, it can be concluded that M. longifolia is a potential natural source for the development of new drugs. However, further studies are required to determine the precise quality and safety of the plant to be used by clinicians.

Phenolic Content, Antioxidant and Astroprotective Response to Oxidative Stress of Ethanolic Extracts of Mentha longifolia from Sinai

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.

Nutritional quality and essential oil compositions of Thaumatococcus danielli (Benn.) tissue and seed

Nutritional quality and essential oil compositions of Thaumatococcus danielli (Benn.) tissue and seed were determined. Oil was extracted from the seed using standard methods while the fatty acids of the oil, chemical and anti-nutritional properties of defatted seed flour were determined. Total fat yield of the seed flour was 12.20%. Defatted seed flour had higher crude fibre (36.92%), carbohydrate (40.07%) and ash (8.17%) contents. Major mineral contents were potassium, calcium, sodium and magnesium. The tissue contain appreciable amount of vitamin C (8.10 mg/100 g). Oleic acid (42.59%) was the major fatty acid in the seed oil and the total unsaturated fatty acid was 62.38%. The seed oil had higher acid and saponification values and low iodine value. Oxalate (11.09 mg/100 g) content was the major anti-nutrient in the defatted seed flour. Defatted T. danielli seed flour serves as good source of dietary fibre and energy.

Compositional Analysis and in vitro Protective Activity against Oxidative Stress of Essential Oils from Egyptian Plants Used in Traditional Medicine

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.

Borneol alleviates oxidative stress via upregulation of Nrf2 and Bcl-2 in SH-SY5Y cells

CONTEXT

The β-amyloid (Aβ) peptide aggregation with accompanying oxidative stress plays the major role in the pathogenesis of Alzheimer's disease (AD). Some natural compounds, including borneol, shed promising light on AD treatment.

OBJECTIVE

The present study was designed to investigate the antioxidative, antiapoptotic effects, and neuroprotection of borneol in human neuroblastoma cells (SH-SY5Y).

MATERIALS AND METHODS

Oxidative stress was induced by administering 50 µM Aβ into SH-SY5Y cells. Neuroprotective effect of commercially available borneol was examined by determining cell viability with the MTT assay. Intracellular reactive oxygen species (ROS) generation was measured using a fluorometer with further examination of heme oxygenase-1 (HO-1) and nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) expression. Apoptosis was examined by measuring the ratio of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax).

RESULTS

Our data indicated that Aβ-induced cell cytotoxicity was inhibited by 100 µM of (-) and (+) borneol treatment. Treatment of borneol significantly decreased ROS generation (P < 0.01). The expression of HO-1 and nuclear translocation of Nrf2 were increased by Aβ treatment. This nuclear translocation of Nrf2 was further increased by administration of borneol. Compared with the Aβ treated group, the (+) borneol treated group significantly increased Bcl-2 expression with decreased expression of Bax.

DISCUSSION AND CONCLUSION

Borneol protected SH-SY5Y cells against Aβ-induced toxicity, exerted an antioxidative effect and suppressed apoptosis. It increases our knowledge about neuroprotective mechanism of borneol, and it is hopeful to be a candidate compound for developing therapeutic drug for the prevention and treatment of AD and other Aβ-related neurodegenerative diseases.

Antifungal effect of Mexican oregano (Lippia berlandieri Schauer) essential oil on a wheat flour-based medium

The antimicrobial activity of oregano has been attributed mainly to the presence of volatile compounds found in its essential oil (EO), mainly carvacrol and thymol. The search for antimicrobial activity of oregano EO with different concentrations of thymol and carvacrol, can lead to products with a wider range of applications. The aim of this work was to describe the in vitro antifungal effect of Mexican oregano (Lippia berlandieri Schauer) EO fractions on the growth of Aspergillus, Penicillium, and Rhizopus sp. The Mexican oregano EO fractions studied had different concentrations of carvacrol, which decreased from fraction 1 to 5 (81% to 23%), while thymol content increased from 3% to 64%. Fungal inhibition was evaluated on a wheat flour-based medium with EO fractions concentrations ranging from 50 to 200 mg/kg. Radial growth curves were fitted using the modified Gompertz model (R(2)(adj) = 0.989 ± 0.01). No significant differences (P > 0.05) were found with the different composition of the Mexican oregano EO fractions; nevertheless, fraction concentration presented significant (P < 0.05) mold inhibition as concentration increased. Rhizopus sp. (Rh18) showed a linear reduction on specific growth rate, on the maximum mold growth at the stationary phase, and an increase in the lag time as the concentration of the oregano EO increased; mold growth inhibition were achieved at 150 mg/kg in fractions 1 to 4, and at 100 mg/kg for fraction 5. Aspergillus sp. (As6) and Penicillium sp. (Pe36) were inhibited at 150 and 200 mg/kg, respectively. Results obtained suggest that Mexican oregano EO (Lippia berlandieri Schauer) compounds could be used as antimicrobial agents to prevent fungal growth in bakery products.

Assessment of geraniol-incorporated polymers to control Aedes albopictus (Diptera: Culicidae)

Effective control of mosquito borne diseases has proven extremely difficult with both vector and pathogen remaining entrenched and expanding in many disease endemic areas. When lacking an effective vaccine, vector control methods targeting both larval habitats and adult mosquito populations remain the primary strategy for reducing risk. Aedes albopictus from Thailand was used as a reference baseline for evaluation of natural insecticides incorporated in polymer disks and pellets and tested both in laboratory and field conditions. In laboratory and field tests, the highest larval mortality was obtained with disks or pellets containing IKHC (Insect Killer Highly Concentrate) from Fulltec AG Company. This product is reputed to contain geraniol as an active ingredient. With pellets, high mortality of Ae. albopictus larvae (92%) was observed in presence of 1 g of pellets per 500 ml of water at day 1st, and the mortality was 100% at day 1st for larvae in presence of 5 or 10 g of pellets. Fulltec AG Company has not accepted to give us the exact composition of their IKHC product. Therefore, we cannot recommend it, but the principle of using monoterpenes like geraniol, incorporated into polymer disks or pellets as natural larvicide needs more attention as it could be considered as a powerful alternative in mosquito vector control.

An evidence-based systematic review of spearmint by the natural standard research collaboration

An evidence-based systematic review of spearmint (Mentha spicata, Mentha viridis) including written and statistical analysis of scientific literature, expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

Chemical composition and antimicrobial activity of the essential oil of kumquat (Fortunella crassifolia Swingle) peel

The aim of this study was to determine the main constituents of the essential oil isolated from Fortunella crassifolia Swingle peel by hydro-distillation, and to test the efficacy of the essential oil on antimicrobial activity. Twenty-five components, representing 92.36% of the total oil, were identified by GC-MS analysis. The essential oil showed potent antimicrobial activity against both Gram-negative (E. coli and S. typhimurium) and Gram-positive (S. aureus, B. cereus, B. subtilis, L. bulgaricus, and B. laterosporus) bacteria, together with a remarkable antifungal activity against C. albicans. In a food model of beef extract, the essential oil was observed to possess an effective capacity to control the total counts of viable bacteria. Furthermore, the essential oil showed strongly detrimental effects on the growth and morphological structure of the tested bacteria. It was suggested that the essential oil from Fortunella crassifolia Swingle peel might be used as a natural food preservative against bacteria or fungus in the food industry.

Chrysolina herbacea modulates terpenoid biosynthesis of Mentha aquatica L

Interactions between herbivorous insects and plants storing terpenoids are poorly understood. This study describes the ability of Chrysolina herbacea to use volatiles emitted by undamaged Mentha aquatica plants as attractants and the plant's response to herbivory, which involves the production of deterrent molecules. Emitted plant volatiles were analyzed by GC-MS. The insect's response to plant volatiles was tested by Y-tube olfactometer bioassays. Total RNA was extracted from control plants, mechanically damaged leaves, and leaves damaged by herbivores. The terpenoid quantitative gene expressions (qPCR) were then assayed. Upon herbivory, M. aquatica synthesizes and emits (+)-menthofuran, which acts as a deterrent to C. herbacea. Herbivory was found to up-regulate the expression of genes involved in terpenoid biosynthesis. The increased emission of (+)-menthofuran was correlated with the upregulation of (+)-menthofuran synthase.

Ethnopharmacological survey of medicinal plants in Nor-Yauyos, a part of the Landscape Reserve Nor-Yauyos-Cochas, Peru

AIM OF THE STUDY

To collect, analyze and evaluate the ethnopharmacologic knowledge in Nor-Yauyos in order to protect it. This paper reports the results of an ethnopharmacological survey on the uses of medicinal plants by inhabitants of the Andean region Nor-Yauyos, Peru. In this region one surviving ethnic group, the Jaqaru-Quichuas, has been identified.

METHODOLOGY

Field work was concluded between October 1999 and March 2000, using semi-structured questionnaire and participant observation as well as transects walks in wild herbal plant collection. Interviews with 68 informants (mean age: 54; 100% men, 0% women) were performed in 12 farmers' communities: Huancaya, Vilca, Vitis, Miraflores, Piños, Carania, San Lorenzo De Alis, Santa Rosa De Tinco, Tomás, Huancachi, Laraos and Huantán.

RESULTS

63 species of plants belonging to 29 families were reported. More than a half of reported plants were native, endemic of the studied area. Leaves and their mixtures were the most (67.26%) commonly used plant part. Most of the remedies were prepared in infusion, and 90.08% were administered orally. Most treated disorders were the gastrointestinal (18.59%) and respiratory ones (18.22%).

CONCLUSIONS

6 species (9.52%) without pharmacological references in international scientific literature, 21 species (33.33%) with 1-2 references, 16 species (25.40%) with 3-6 references, and 20 species (31.75%) that have been already widely studied were found.

Yield, content, and composition of peppermint and spearmints as a function of harvesting time and drying

Peppermint ( Mentha × piperita L.) and spearmints ('Scotch' spearmint, M. × gracilis Sole, and 'Native' spearmint, Mentha spicata L.) are widely grown essential oil crops in more northern latitudes; however, there is limited information on how harvest time and drying influence peppermint and spearmint yield, oil composition, and bioactivity, when grown south of the 41st parallel. In this 2-year study, the effects of harvest time and drying on the yield, oil composition, and bioactivity of peppermint ('Black Mitcham' and 'B90-9'), 'Scotch' spearmint, and 'Native' spearmint were evaluated. Peppermint oil from the dried material had higher menthol and eucalyptol concentrations. Menthone in both peppermint cultivars decreased from harvest 1 (late June) to harvest 5 (late August) or 6 (early September), whereas menthol increased. (-)-Carvone in spearmints accumulated early, before flowering, allowing for early harvest. Oil yields from the dried spearmint biomass reached the maximum at harvest 3 (mid-July). The essential oil compositions of the four mint genotypes were similar to that of 11 commercially available oils, suggesting that these genotypes can be grown in the hot, humid environment of the southeastern United States. The antioxidant activities (ORAC(oil) values) of the essential oils were 4372, 1713, 1107, and 471 μmol of TE L(-1) for 'Scotch' spearmint, 'Native' spearmint, peppermint, and Japanese cornmint ( Mentha canadensis ), respectively. The oils of the four mint genotypes did not affect ruminal fermentation in vivo, and did not exhibit antimicrobial, antileishmanial, or antimalarial activity at levels that would warrant bioassay-directed fractionation in a drug-discovery screening program. Specifically, the oils did not show greater than 50% growth inhibition against Leishmania donovani , Plasmodium falciparum clones D6 and W2, Candida albicans , Escherichia coli , Pseudomonas aeruginosa , Cryptococcus neoformans , Mycobacterium intracellulare , or Aspergillus fumigates at 50 μg mL(-1).