Piperitone

Chemical diversity and biological activities of essential oils from native populations of Clinopodium menthifolium subsp. ascendens (Jord.) Govaerts.[Pubmed:33190203]

Environ Sci Pollut Res Int. 2020 Nov 14. pii: 10.1007/s11356-020-11523-3.

This study is focused on the analysis of regional variation of the chemical compositions of three Clinopodium menthifolium subsp. ascendens (Jord.) Govaerts Tunisian accession, as well as their inhibition toward fungi and insect pests. The diversity of the chemical constituents and biological activities in front of the aforementioned variations was found to be remarkable. Essential oils were obtained by hydrodistillation of the aerial parts and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 41, 42, and 30 compounds were identified respectively from Clinopodium menthifolium essential oils harvested from three Tunisian regions, namely Ain-Draham (ADEO), Babouch (BEO), and Tabarka (TEO). All analyzed oils were rich in oxygenated monoterpenes with different major constituents. Piperitenone (34.5%), cis-Piperitone oxide (26.1%), and pulegone (47.9%) were the dominant compounds in the three volatile oils, respectively. The antifungal activity was investigated in vitro using six targeted fungal strains (Aspergillus flavus, Aspergillus terreus, Candida albicans, Microsporum canis, Microsporum gypseum, and Trichophyton mentagrophytes). The toxicity and repellency of essential oils were evaluated against the stored product pest Tribolium confusum. The tested samples were differently effective toward the target fungi and the pest depending on the variability of their chemical compositions. BEO exhibited the highest fungitoxic properties toward A. terreus mold, M. canis dermatophyte, and C. albicans yeast (the MIC values ranged from 40 to 400 mug mL(-1)). In addition, the data showed that TEO repelled T. confusum moderately (PR = 42.5% at 2 h after exposure). Concerning the contact treatment, both ADEO and BEO were proved to possess slightly toxic effects toward T. confusum pest (% of mortality 27.5-32.5% at 5% concentration). The results showed that the geographic origin greatly influenced the chemical composition and the associated bioactivities of Clinopodium menthifolium subsp. ascendens.

Cherry tomato and persimmon kaki conservation with a natural and biodegradable film.[Pubmed:32914109]

Curr Res Food Sci. 2019 Dec 12;2:33-40.

The chemical composition of Essential Oils Satureja montana and Mentha longifolia was determined, and their activity against important phytopathogenic and post-harvest fungi was studied, to evaluate their potential as natural food preservatives. The major compounds were carvacrol (24.0%), gamma-terpinene (15.9%) and p-cymene (14.2%) in S. montana, and piperitenone oxide (52.7%) and Piperitone oxide (23.5%) in M. longifolia. EOs were tested in vitro on Alternaria alternata, Botryotinia fuckeliana, Curvularia hawaiiensis, Fusarium equiseti, F. oxysporum lycopersici, Rhizoctonia solani and Verticillium dahliae. S. montana demonstrated excellent results. At 300 mug mL(-1) the growth of all fungi was inhibited with 100% mycelial growth inhibition (MGI), except for B. fuckeliana (92%). M. longifolia was less effective, and its best result was against Verticillium dahliae (100% MGI) at 400 and 300 mug mL(-1). S. montana EO was selected for in vivo antifungal tests in Cherry tomatoes and kaki "Persimmon" against A. alternata. The S. montana EO biofilm reduced post-harvest fungi development. In tomato, it inhibited up to 90% after 20 days. Necrosis did not occur for 2 months in the persimmon fruits. S. montana EO is an effective non-toxic preservative that can be considered to develop a botanical and enviro-friendly low-risk biofungicide.

A review of medicinal plant of Middle East and North Africa (MENA) region as source in tuberculosis drug discovery.[Pubmed:32884430]

Saudi J Biol Sci. 2020 Sep;27(9):2457-2478.

Tuberculosis (TB) is a disease that affects one-third of the world's population. Although currently available TB drugs have many side effects, such as nausea, headache and gastrointestinal discomfort, no new anti-TB drugs have been produced in the past 30years. Therefore, the discovery of a new anti-TB agent with minimal or no side effects is urgently needed. Many previous works have reported the effects of medicinal plants against Mycobacterium tuberculosis (MTB). However, none have focused on medicinal plants from the Middle Eastern and North African (MENA) region. This review highlights the effects of medicinal plants from the MENA region on TB. Medicinal plants from the MENA region have been successfully used as traditional medicine and first aid against TB related problems. A total of 184 plants species representing 73 families were studied. Amongst these species, 93 species contained more active compounds with strong anti-MTB activity (crude extracts and/or bioactive compounds with activities of 0-100microg/ml). The extract of Inula helenium, Khaya senegalensis, Premna odorata and Rosmarinus officinalis presented the strongest anti-MTB activity. In addition, Boswellia papyrifera (Del) Hochst olibanum, Eucalyptus camaldulensis Dehnh leaves (river red gum), Nigella sativa (black cumin) seeds and genus Cymbopogon exhibited anti-TB activity. The most potent bioactive compounds included alantolactone, octyl acetate, 1,8-cineole, thymoquinone, Piperitone, alpha- verbenol, citral b and alpha-pinene. These compounds affect the permeability of microbial plasma membranes, thus kill the mycobacterium spp. As a conclusion, plant species collected from the MENA region are potential sources of novel drugs against TB.

Evaluation of larvicidal potential against larvae of Aedes aegypti (Linnaeus, 1762) and of the antimicrobial activity of essential oil obtained from the leaves of Origanum majorana L.[Pubmed:32678859]

PLoS One. 2020 Jul 17;15(7):e0235740.

This study evaluated the larvicidal activity of Origanum majorana Linnaeus essential oil, identified the chemical composition, evaluated the antimicrobial, cytotoxic and antioxidant potential. The larvicidal activity was evaluated against larvae of the third stage of Aedes aegypti Linaeus, whereas the chemical composition was identified by gas chromatography coupled to mass spectrometer, the antimicrobial activity was carried out against the bacteria Pseudomonas aeruginosa, Escherichia coli and Staphylococcus auereus, the antioxidant activity was evaluated from of 2.2-diphenyl-1-picryl-hydrazila sequestration and Artemia salina Leach cytotoxicity. Regarding to the results, the larvicidal activity showed that O. majorana L. essential oil caused high mortality in A. aegypti L. larvae. In the chromatographic analysis, the main component found in O. majorana L. essential oil was pulegone (57.05%), followed by the other components verbenone (16.92%), trans-p-menthan-2-one (8.57%), iso-menthone (5.58%), Piperitone (2.83%), 3-octanol (2.35%) and isopulegol (1.47%). The antimicrobial activity showed that E. coli and P. aeruginosa bacteria were more sensitive to oil than S. aureus, which was resistant at all concentrations. Essential oil did not present antioxidant activity, but it has high cytotoxic activity against A. salina L.

Semiochemicals Affecting Attraction of Ambrosia Beetle Euwallacea fornicatus (Coleoptera: Curculionidae: Scolytinae) to Quercivorol: Developing Push-Pull Control.[Pubmed:32596735]

J Econ Entomol. 2020 Oct 16;113(5):2120-2127.

Euwallacea fornicatus (Eichhoff), the polyphagous shot hole borer (PSHB), is an ambrosia beetle infesting avocado Persea americana Mill. limbs in North America and Israel. We conducted field experiments with sticky traps in avocado orchards to develop push-pull semiochemical methods of managing PSHB. Traps baited with 10-fold increasing doses (0.01 to 100x or 1.26 microg to 12.6 mg/d) of attractant quercivorol were previously shown to increasingly capture female PSHB (males flightless). We converted trap catch of this relationship to a standardized effective attraction radius (EAR) that predicts capture power of baited-traps regardless of insect flight density. Earlier, Piperitone and verbenone were shown to strongly inhibit attraction of PSHB to quercivorol-traps. We tested increasing numbers of 1x Piperitone dispensers at 0.75-m distance surrounding a quercivorol-trap and found PSHB catch to decline exponentially. Increasing decadic doses (0.01 to 10x) of either verbenone or Piperitone released at 1x quercivorol-traps caused a sigmoidal first-order kinetic-decay in catch. Verbenone (1x) placed at increasing distances (0, 0.25, 0.5, 1, and 2 m) from a 1x quercivorol-trap became increasingly ineffective in reducing catch of PSHB. We found no evidence that ethanol released from 7.5 to 480 mg/d affected attraction of PSHB, but Scobicia chevrieri (Villa and Villa) (Coleoptera: Bostrichidae) was increasingly attracted. Due to their relatively short-range (<0.5 m) inhibition of attractive sources, Piperitone, and verbenone dispensers should be placed on avocado trunks where PSHB aggregations occur before the flight season.

Volatile Components of Haplophyllum canaliculatum Boiss. by Different Extraction Procedures.[Pubmed:32566357]

J Anal Methods Chem. 2020 May 30;2020:4202871.

Volatile components of Haplophyllum canaliculatum Boiss. grown in Iran were extracted by hydrodistillation (HD), solvent-free microwave extraction (SFME), and headspace solid-phase microextraction (HS-SPME). The components were analyzed by means of GC and GC-MS. The extraction time and temperature for HS-SPME, microwave, power, and exposure time of extraction for SFME were optimized. Twenty-five compounds that represent 99.88% of total compounds in the oil were obtained by the HD method, and the major components for this method were identified as beta-pinene (18.90%), 1,8-cineole (13.94%), and Piperitone (12.22%). However, Piperitone (34.50%), caryophyllene oxide (9.94%), and a-eudesmol were the main compounds among twenty-one constituents, representing 99.89% of the total composition that were characterized in volatiles extracted by the SFME method. Moreover, thirteen compounds, representing 99.95% of the total constituents, were characterized in volatile fraction extracted by the HS-SPME method, which were dominated by beta-pinene (21.13%), a-pinene (13.07%), limonene (11.65%), and delta-2-carene (10.23%) as major constituents.

Screening the antifungal activities of monoterpenes and their isomers against Candida species.[Pubmed:32506599]

J Appl Microbiol. 2020 Dec;129(6):1541-1551.

AIM: Increasing the occurrence of non-albicans Candida species with intrinsic or acquired resistance to antifungals as well as the emergence of multidrug Candida species coupled with the limited antifungal agents challenges the treatment of candidiasis. Consequently, a class of secondary metabolites of plants exhibiting decent antifungal activity. Therefore, this study aimed to evaluate the antifungal potential of various monoterpenes including Carvone, Limonene, Pinene, Menthone, Menthol, Camphor, Thujone, Citronellol, and Piperitone against standard and clinical isolates of Candida. METHODS AND RESULTS: Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of compounds were determined, using the broth Microdilution method based on M27-A3 protocol documented by clinical laboratory standard institute (CLSI). Amongst the tested monoterpenes, oxygenated terpenoids showed strong antifungal activity. Specifically, alcoholic terpenoids such as (+/-)-Citronellol possess more efficacy than the corresponding ketonic ones with MICs ranging from 0.03 to 2.00 mul ml(-1) (0.16-10.80 mmol l(-1) ). Among the examined yeasts, Candida tropicalis was the most susceptible species to (+/-)-Citronellol. Moreover, the examined monoterpenes successfully inhibited the growth of fluconazole-resistant Candida species. Moreover, statistical analysis showed no statistically significant difference between the (+) and (-) isomers, except for (+/-)-alpha-Pienene and (+/-) Menthone (rho-value < 0.05). CONCLUSION: Among the tested monoterpenes, (+/-)-Citronellol was the most potent compounds followed by (+)-alpha-Pinene and Menthol. Considering the significant antifungal activity of the examined monoterpenes, they could be used in controlling or treating candidiasis. Those potent antifungal monoterpenes with GRAS status in addition to their pleasant taste and odour make them appropriate additive or preservative compounds in food and cosmetics products. Furthermore, these data might help researchers to predict EOs antifungal activities, after determining its constituents. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new information about the antifungal activities of monoterpenes and their isomers presented widely in essential oils. Screening results against pathogenic yeasts confirm the correlation between the chemical structure of tested monoterpenes and their antifungal effects. The present findings might be helpful to anticipate the antifungal activity of essential oils.

Chemical Composition, Antifungal and Insecticidal Activities of the Essential Oils from Tunisian Clinopodium Nepeta Subsp. nepeta and Clinopodium Nepeta Subsp. Glandulosum.[Pubmed:32370305]

Molecules. 2020 May 2;25(9). pii: molecules25092137.

The present investigation was focused on the study of the chemical composition variability and biological activities of the essential oils from Clinopodium nepeta subsp. nepeta and subsp. glandulosum. Essential oils extraction was performed using hydrodistillation and the separation of the constituents was carried out by gas chromatography coupled with mass spectrometry (GC-MS). Antifungal activities were tested against Aspergillus flavus, Aspergillus terreus, Microsporum canis, Microsporum gypseum, Trichophyton mentagrophytes, and Candida albicans. Toxicity and repellency were evaluated against the stored product pests Tribolium confusum and Sitophilus zeamais. Both essential oils were characterized by a high content of oxygenated monoterpenes. Piperitone ranks first in the subspecies nepeta and piperitenone oxide is the dominant constituent in the subspecies glandulosum. All tested samples displayed noteworthy antifungal properties, with the highest activity observed for the essential oil of C. nepeta subsp. glandulosum, collected in Beni-M'tir, against T. mentagrophytes (MIC = 40 microg/mL). The essential oil samples of C. nepeta subsp. glandulosum were strongly repellent to the insect species (PR > 80%, after 2h) and highly toxic to S. zeamais reaching 97.5%-100% mortality after 24 h of exposure. In conclusion, this study showed considerable intra-specific changes in the quality of C. nepeta essential oils, which is reflected in different rates of antifungal and insecticidal activity.

Conversion and Hydrothermal Decomposition of Major Components of Mint Essential Oil by Small-Scale Subcritical Water Treatment.[Pubmed:32331471]

Molecules. 2020 Apr 22;25(8). pii: molecules25081953.

Thermal stabilities of four major components (l-menthol, l-menthone, Piperitone, and l-menthyl acetate) of Japanese mint essential oil were evaluated via subcritical water treatment. To improve experimental throughput for measuring compound stabilities, a small-scale subcritical water treatment method using ampoule bottles was developed and employed. A mixture of the four major components was treated in subcritical water at 180-240 degrees C for 5-60 min, and then analyzed by gas chromatography. The results indicated that the order of thermal resistance, from strongest to weakest, was: l-menthyl acetate, l-menthol, Piperitone, and l-menthone. In individual treatments of mint flavor components, subsequent conversions of l-menthyl acetate to l-menthol, l-menthol to l-menthone, l-menthone to Piperitone, and Piperitone to thymol were observed in individual treatments at 240 degrees C for 60 min. As the mass balance between Piperitone and thymol was low, the hydrothermal decomposition of the components was considered to have occurred intensely during, or after the conversion. These results explained the degradation of mint essential oil components under subcritical water conditions and provided the basis for optimizing the extraction conditions of mint essential oils using subcritical water.

Chemical characterization, phytotoxic, and cytotoxic activities of essential oil of Mentha longifolia.[Pubmed:32303127]

Environ Sci Pollut Res Int. 2020 Apr;27(12):13512-13523.

The present study assessed the phytotoxic and cytotoxic potential of the essential oil (EO) extracted from aboveground parts of Mentha longifolia (L.) Huds. Gas chromatography-mass spectrometry revealed 39 compounds constituting 99.67% of the EO. The EO was rich in monoterpenoids (mostly oxygenated monoterpenes), which accounted for 89.28% of the oil. The major components in EO were monoterpene ketones such as Piperitone oxide (53.83%) and piperitenone oxide (11.52%), followed by thymol (5.80%), and (E)-caryophyllene (4.88%). The phytotoxic activities of EO were estimated against Cyperus rotundus, Echinochloa crus-galli, and Oryza sativa (rice) through pre- and post-emergence assays at concentrations ranging from 10 to 250 mug/ml and 0.5-5%, respectively. In pre-emergence assay, the phytotoxic effect of EO was most pronounced on C. rotundus, thereby significantly affecting percent germination, plantlet growth, and chlorophyll content. On the contrary, the impact was comparatively lesser on rice, with ~ 40% germination in response to 250 mug/ml of EO treatment. In the post-emergence assay, the spray treatment of EO caused a loss of chlorophyll and wilting in test plants, and subsequently affected the growth of plants, even leading to death in some cases. The cytotoxic activity of EO (at 2.5-50 mug/ml) was studied in meristem cells in onion (Allium cepa L.) root tips. EO exposure to the onion roots induced various chromosomal aberrations such as chromosomal bridges, c-mitosis, stickiness, vagrant chromosomes, etc., and negatively affected the mitotic index. At 50 mug/ml, EO treatment triggered the complete death of roots. The study concludes that M. longifolia EO has phytotoxic activities due to the mito-depressive effect, along with other physiological effects on target plants. Therefore, EO of M. longifolia could be developed into a novel bioherbicide for sustainable management of weeds in agricultural systems.

Achillea filipendulina Lam.: Chemical Constituents and Antimicrobial Activities of Essential Oil of Stem, Leaf, and Flower.[Pubmed:32239617]

Chem Biodivers. 2020 May;17(5):e2000133.

In this study, we extracted the essential oils of the stem, leaf, and flower of Achillea filipendulina, analyzed them, and studied their antibacterial properties. Of 16, 53, and 35 compounds identified in the stem, leaf, and flowers, respectively, only five are present in all three segments of the plant. The essential oil of the stem was mainly composed of neryl acetate, spathulenol, carvacrol, santolina alcohol, and trans-caryophyllene oxide. However, the main identified components of leaf were 1,8-cineole, camphor, ascaridole, trans-isoascaridole, and Piperitone oxide and the main components of the flower oil were ascaridole, trans-isoascaridole, 1,8-cineole, p-cymene, and camphor. The extracted oil from different segments demonstrated varying antibacterial properties against both Gram-positive and Gram-negative bacteria, demonstrated by disk, minimum inhibitory concentration, and minimum bactericidal concentration methods. These suggest that the application of all segments of aerial parts of A. filipendulina may have a better therapeutic effect in fighting pathogenic systems.

Contribution of Volatile Odorous Terpenoid Compounds to Aged Cognac Spirits Aroma in a Context of Multicomponent Odor Mixtures.[Pubmed:32052967]

J Agric Food Chem. 2020 Nov 25;68(47):13310-13318.

Cognac spirit aromas result from the presence of a wide variety of volatile odorous compounds associated with the modalities of spirit distillation and aging. However, very few studies have been carried out on aging notes of Cognac spirits. An HPLC fractionation approach was used in order to evidence fractions of interest recalling the specific aromatic nuances of aged Cognac. Then, a GC-O/MS analysis of the selected fractions allowed one to detect odorous zones and identify several volatile compounds. Among them, various well-known volatile compounds representative of the terpenoid family were highlighted, such as geraniol, alpha-terpinene, nerol, alpha-terpineol, 1,8-cineole (eucalyptol) and, particularly, Piperitone, santalol, and alpha-campholenal, which have not previously been cited in Cognac. These compounds were quantitated and their detection thresholds were determined. Geraniol, alpha-terpinene, alpha-terpineol, and 1,8-cineole concentrations increased while spirits were more aged, while nerol tends to decrease. A sensory contribution of terpenes was observed through perceptual synergic effects, along with beta-damascenone and whisky lactone.

A Detailed Biological and Chemical Investigation of Sixteen Achillea Species' Essential Oils via Chemometric Approach.[Pubmed:31999042]

Chem Biodivers. 2020 Mar;17(3):e1900484.

Representatives of the Achillea genus are widely used as foods or nutraceuticals. Considering the increasing demand for herbal dietary supplements with health promoting effects, the objective of this research was to evaluate the chemical composition and biological activities of the essential oils obtained from sixteen Achillea species (A. biebersteinii, A. wilhelmsii subsp. wilhelmsii, A. aleppica subsp. zederbaueri, A. vermicularis, A. monocephala, A. nobilis, A. goniocephala, A. sintenisii, A. coarctata, A. kotschyi subsp. kotschyi, A. millefolium subsp. millefolium, A. lycaonica, A. spinulifolia, A. teretifolia, A. setacea, and A. schischkinii). Anticholinesterase, antiurease, antityrosinase enzymes inhibition, antioxidant, antimicrobial, toxic and cytotoxic activities of obtained essential oils were investigated. DPPH activities were found to be very low in all studied samples, while ABTS and CUPRAC antioxidant activities were found to be moderate. In addition, all samples were found to have moderate anticholinesterase and antimicrobial effects. It has been determined that the studied species have low cytotoxicity and high toxicity. Besides, chemical composition of the essential oils were determined by GC/MS and the results were chemometrically analyzed. The chemometric analyses of Achillea species collected from nine different regions were accomplished by principal component analysis (PCA) and hierarchical cluster analysis (HCA) techniques. According to the PCA analysis, A. nobilis subsp. neilreichii was found to be different from all studied species in terms of essential oil composition. The major components found in these species were Piperitone, camphor, alpha-terpinene, eucalyptol, artemisia ketone, endo-borneol, beta-eudesmol and verbenol. The fact that camphor was toxic and found in majority of the studied species stands out as a remarkable result.

Synthesis, structural assignments and antiinfective activities of 3-O-benzyl-carvotacetone and 3-hydroxy-2-isopropyl-5-methyl-p-benzoquinone.[Pubmed:31997645]

Nat Prod Res. 2020 Jan 30:1-9.

In an attempt to synthesize carvotacetone analogues, new 3-O-benzyl-carvotacetone (10) and previously reported 3-hydroxy-2-isopropyl-5-methyl-p-benzoquinone (11) were synthesized from Piperitone (7). In this work, we describe the synthesis of 10 and other analogues from 7. Luche reduction of 7 to cis-piperitol (8), followed by benzylation yielded 3-O-benzyl-piperitol (9). Riley oxidation of 9 afforded corresponding ketone 10, 11 and 3-benzyloxy-4-isopropylcyclohex-1-enecarbaldehyde (12). Structures of these compounds were determined based on NMR, IR and LC-MS spectral data. Compound 11, exhibited antiplasmodial activities against chloroquine-sensitive (D6) and resistant (W2) strains of Plasmodium falciparum with IC50 values of 0.697 and 0.653 microg/mL, respectively. In addition, compound 11 was active against Cryptococcus neoformans with an IC50 value of 3.11 microg/mL, compared to reference standard fluconazole (IC50 value of 1.87 microg/mL), while 10 and 12 were inactive against both organisms. This is the first report of the antiplasmodial and anticryptococcal activity of compound 11.

Chemical profile, antiproliferative, antioxidant, and enzyme inhibition activities and docking studies of Cymbopogon schoenanthus (L.) Spreng. and Cymbopogon nervatus (Hochst.) Chiov. from Sudan.[Pubmed:31808956]

J Food Biochem. 2020 Feb;44(2):e13107.

Essential oils from the inflorescence of Cymbopogon schoenanthus and C. nervatus growing in Northern Sudan were examined for their chemical composition, antiproliferative activity against human breast carcinoma and human colon adenocarcinoma cell lines, antioxidant activity (phosphomolybdenum, antiradical, reducing power, and ferrous chelating), and enzyme inhibition activity against acetylcholinesterase butyrylcholinesterase, tyrosinase, alpha-glucosidase, and alpha-amylase. In silico study on the inhibition of tyrosinase and alpha-amylase was also performed. Piperitone (59.1%) and isomers of para-menthadienols (35.3%) were the main compounds in C. schoenanthus and C. nervatus oils, respectively. Oil from C. nervatus possessed higher antioxidant activity than that from C. schoenanthus except for its metal chelating ability. Both oils showed high antiproliferative activity. In silico study showed that trans-p-mentha-2,8-dien-1-ol and Piperitone (both isomers) revealed the best docking scores for alpha-amylase and tyrosinase, respectively. In conclusion, oils from these two Cymbopogon species could be new natural agents with functional properties for food, cosmetics, and pharmaceutical industries. PRACTICAL APPLICATIONS: Recently, there is a growing tendency to replace synthetic oils by natural ones in the cosmetic, food, and pharmaceutical products. In this context, we investigated the chemical characterization and biological activities of two Cymbopogon species essential oils (C. schoenanthus (L.) Spreng. and C. nervatus). Antioxidant capacity, enzyme inhibition, and antiproliferative effects were tested for biological activities. Chemical characterization was identified by GC-MS. Based on our findings, the Cymbopogon species may be utilized as sources of natural bioactive agents in food industries.