Herein, comprehensive data of NMR, MS, IR, and gas chromatography (RI) obtained by GC-MS on commonly used capillary columns of different polarity (non-polar DB-5MS and polar HP-Innowax) of a series ...of esters of all constitutional isomers of hexanoic acid with a homologous series of ω-phenylalkan-1-ols (phenylmethanol, 2-phenylethanol, 3-phenylpropan-1-ol, 4-phenylbutan-1-ol, and 5-phenylpentan-1-ol) and phenol, in total 48 chemical entities, were collected. The created synthetic library allowed the identification of a new constituent of the
essential oil (3-phenylpropyl 2-methylpentanoate). The accumulated spectral and chromatographical data, as well as the established correlation between RI values and structures of regioisomeric hexanoates, provide (phyto)chemists with a tool that will make future identification of related natural compounds a straightforward task.
•A new natural product 5-phenylpentyl isothiocyanate (PhPeITC) was found in horseradish.•The first direct proof of the existence of a 5-phenylpentyl glucosinolate in nature.•PhPeITC and four related ...isothiocyanates were synthesised and extensively tested.•PhPeITC possesses spasmolytic activity 100 times more potent than papaverine.•Horseradish constituents showed significant cytotoxicity and antimicrobial activity.
Detailed analyses of horseradish autolysates led to the identification of a new natural product, 5-phenylpentyl isothiocyanate (PhPeITC). The structural assignment was corroborated by synthesis, and the identity unequivocally established by spectral means. The occurrence of PhPeITC is the first direct proof of the existence of a 5-phenylpentyl glucosinolate in the aerial parts of this species as one of the possible “mustard oil” precursors. To verify its possible contribution to the horseradish functional food status, horseradish above- and underground autolysates, together with five ω-phenylalkyl isothiocyanates were tested for their spasmolytic, cytotoxic and antimicrobial activities. Specifically, the cytotoxic effect on Caco-2, HeLa (cancer) and MDCK (non-cancer) cell lines was established. Additionally, the five tested ITCs exerted significant spasmolytic activity (on rat distal colon), with PhPeITC being almost 100 times more potent than papaverine. A non-selective antimicrobial activity of all ITCs was revealed in the case of 6 bacterial and 2 fungal strains.
The design and synthesis of analogs of natural products can be a valuable source of medicinal preparations for the pharmaceutical industry. In the present study, the structural elucidation of eleven ...derivatives of 2,4-dihalogeno substituted synthetic analogues of the natural compound carvacrol was carried out by means of NMR experiments, and of another thirteen by DFT calculations. By selective NOE experiments and the irradiation of CH signals of the isopropyl group, individual conformers were assigned as
and
. By comparing GIAO/B3LYP/6-311++G(d,p)-calculated and experimentally measured vicinal
spin-spin constants, this assignment was confirmed. An unusual relationship is reported for proton-carbon vicinal couplings:
(180°) <
(0°). The conformational mobility of carvacrols was studied by 2D EXSY spectra. The application of homonuclear decoupling technique (HOBS) to these spectra simplifies the spectra, improves resolution without reducing the sensitivity, and allows a systematic examination of the rotational barrier of all compounds via their CH signals of the isopropyl group in a wider temperature interval. The rate constants of the isopropyl rotation between
and
conformers were determined and the corresponding energy barriers (14-17 kcal/mol) were calculated. DFT calculations of the energy barriers in carvacrol derivatives allowed the determination of the steric origin of the restricted isopropyl rotation. The barrier height depends on the size of the 2- and 4-position substituents, and is independent of the derivatization of the OH group.
Among the fewest drugs discovered are those belonging to the class of anxiolytics. Although some drug targets for anxiety disorders are established, it is hard to modify and selectively choose the ...active principle for those targets. Thus, the ethnomedical approach to treating anxiety disorders remains one of the most prevalent ways for (self)managing the symptoms. Melissa officinalis L. (lemon balm) has been extensively used as an ethnomedicinal remedy for the treatment of different psyche-related symptoms, especially dose related to restlessness.
This work aimed to evaluate the anxiolytic activity, in several in vivo models, of the essential oil extracted from Melissa officinalis (MO) and its main constituent citronellal, a widespread plant utilized for managing anxiety.
In the present study several animal models were used to assess MO anxiolytic potential in mice. The effect of the MO essential oil applied in doses ranging from 12.5 to 100 mg/kg was estimated in light/dark, hole board, and marble burying tests. In parallel doses of citronellal corresponding to the ones in the MO essential oil were applied to animals to determine if this is the activity carrier.
The results indicate that the MO essential oil exerts anxiolytic potential in all three experimental settings by significantly altering the traced parameters. The effects of citronellal are somewhat inconclusive and should not be interpreted only as anxiolytic but rather as a combination of anti-anxiety and motor-inhibiting effects.
In conclusion, we could say that the results of the present study provide a base for future mechanistic studies that would evaluate the activity of M. officinalis essential oil on various neurotransmitter systems involved in the generation, propagation, and maintenance of anxiety.
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•Melissa officinalis essential oil might possess promising anxiolytic effects.•Citronellal and M. officinalis exert in vivo anxiolytic-like activity.•In a dose of 12.5 mg/kg M. officinalis essential oil acts as anxiolytic.•The anxiolytic activity of citronellal might be due to motor inhibition.
Choisya ternata Kunth (Rutaceae) is native to North America where it is popularly known as "Mexican orange". In this study, the anti-inflammatory effects of the essential oil (EO) obtained from the ...leaves of C. ternata, one of its minor components (ternanthranin-ISOAN) and its two synthetic analogues (methyl and propyl N-methylanthranilate--MAN and PAN) were evaluated. Mice pretreated with the EO (EO) obtained from C. ternata leaves (3-100 mg/kg, p.o.), ISOAN, MAN or PAN (1-30 mg/kg, p.o.) and the reference drugs, morphine (1 mg/kg, p.o.) and acetylsalicylic acid (ASA, 100 mg/kg, p.o.), were evaluated in inflammation models such as formalin and subcutaneous air pouch models, with measurement of cell migration, exudate volume, protein extravasation, nitric oxide and pro-inflammatory cytokines. The EO from C. ternata significantly inhibited the time that the animals spent licking the formalin-injected paw in the second phase of the model at their higher doses (30 and 100 mg/kg, respectively). An inhibition of the inflammatory reaction induced after subcutaneous carrageenan injection into air pouch was also observed. In this model, the EO significantly reduced cell migration, exudate volume, protein extravased, and the increase in levels of inflammatory mediators (nitric oxide, TNF-α and IL-1β). ISOAN, MAN and PAN behaved in the same fashion at much smaller doses. Also, these molecules were able to show significant effects in the reduction of paw edema (at all tested doses) when the phlogistic agent was carrageenan, bradykinin, 5-HT, PGE2, C48/80 or 12-O-tetradecanoylphorbol-acetate (TPA). None of the tested doses had any effect in reducing histamine-induced edema. Our results indicate that the EO from C. ternata and anthranilate derivatives demonstrates an anti-inflammatory effect.
Despite being renowned for its volatiles, the data on the toxicity of the essential oil of lemon balm (Melissa officinalis L., Lamiaceae) is rather limited compared to its solvent/water-soluble ...extractibles. In this study, the aerial parts essential oil of M. officinalis, with over 130 constituents identified herein, 26 of which detected for the first time, was investigated for acute oral toxicity in BALB/c mice. The oil, composed of predominantly monoterpene aldehydes, citronellal (21.2–21.8%), neral (17.8–18.4%), and geranial (22.9–23.5%), which were assayed in parallel with the oil in some tests, induced significant changes in animal behavior, as well as altered biochemical parameters reflecting liver and kidney functions. Different pathological changes in the stomach, duodenum, liver, and kidneys were detected when the oil was administered in doses higher than 1 g kg−1. A depletion in the liver/kidney antioxidant capacities and an increased rate of lipid peroxidation was noted for animals treated with lemon balm oil. The calculated value of the oral LD50 in BALB/c mice (2.57 g kg−1) infers that the essential oil is only moderately toxic.
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•Twenty-six compounds are reported here for the first time as constituents of M. officinalis essential oil.•Oral application of lemon balm essential oil causes significant changes in mice behavior, and liver and kidney functions.•Above 1 g kg−1 (p.o.), different pathological changes in the stomach, duodenum, liver, and kidneys were detected.•The essential oil produced a depletion of liver/kidney antioxidant capacities and increased the rate of lipid peroxidation.•The determined oral LD50 in BALB/c mice (2.57 g kg−1) suggests that the essential oil is only moderately toxic.
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•A series of esters of diastereomeric menthols was analyzed by GC–MS.•A foolproof identification procedure for these aroma important esters was suggested.•EI Mass Spectral Libraries ...recorded on SQ and QIT mass detectors were created.•GC RI data on non-polar HP-5MS and polar HP-Innowax columns are included therein.•A collection of MS and GC data was compiled and is available as supplementary data.
A comprehensive data collection of mass spectral and gas chromatographic data of a series of esters of diastereomeric menthols (menthol, isomenthol, neomenthol, and neoisomenthol), in total 150 chemical entities, obtained by GC–MS on commonly used capillary columns of different polarity (non-polar HP-5MS and polar HP-Innowax), was created. Also, MS libraries containing electron ionization MS recorded on single quadrupole as well as on quadrupole ion-trap mass detectors together with the RIs on non-polar and polar columns were compiled (available as supplementary materials). The results point out to frequent misidentification of neoisomenthyl acetate as isomenthyl acetate in the literature, and the means of how to resolve this issue was suggested. The outcomes of this study provide chemists and food technologists with a useful tool in the field of food analysis of compounds with important food aroma properties.
2,6-Cyclocuparan-3-ols are chemical markers and major volatiles of several liverwort species. Conflicting reports on the structures of these cyclocuparanols can be found in the literature–different ...research groups assigned the same spectral data to different structures, yet these inconsistencies were never addressed, let alone satisfactorily explained. Following the isolation of all four diastereoisomeric cyclocuparanols from Marchantia polymorpha, their relative and absolute configurations were extensively studied by chemical and spectroscopic methods and definite stereostructures were proposed.
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•Cyclocuparanols are important marker compounds for several Machantia species.•Several groups published different structures of these compounds.•Conflicting reports were resolved following an extensive structural elucidation.
Besides psyche-related symptoms, patients with anxiety disorders can have a large number of somatic symptoms as well. Although the treatment of these disorders is mainly focused on resolving their ...mental component, one cannot neglect the need for the treatment of accompanying somatic symptoms. Melissa officinalis L. (lemon balm), in various formulations, has been extensively used as an ethnomedicinal remedy for the treatment of different psyche-related symptoms, and its use is considered relatively safe.
Aim of the study: In the present study, the activity of M. officinalis (MO) essential oil was evaluated in several in vitro and in vivo models mimicking or involving anxiety-related somatic symptoms.
To address the effect of MO essential oil on the gastrointestinal and heart-related symptoms accompanying anxiety disorders, in vitro models were utilized that follow the function of the isolated mouse ileum and atria tissues, respectively, after exposure to MO essential oil. Effects of MO essential oil on BALB/c mice motor activity was estimated using the open field, rota-rod, and horizontal wire tests. Additionally, the essential oil was assayed for its potential in inhibiting acetylcholinesterase activity.
The performance of mice treated with 25 mg/kg of the oil showed a statistically significant decrease in the motor impairment arising from acute anxiety (open field test), while there was a prolonged latency and a reduction of the frequency of falling from a rotating rod and/or a horizontal wire (signs of muscle weakness/spasms). Concentrations of the essential oil higher than 1 μg/mL were found to inhibit both spontaneous and induced ileum contractions. Moreover, the essential oil and citronellal were found to decrease isolated mouse atria contraction frequency, as well as contraction force. However, the oil was found to be a very weak acetylcholinesterase inhibitor.
The modulation of anxiety-related symptoms by the oil was found not to be mediated through the inhibition of the acetylcholinesterase, nonetheless, the mechanistic studies involving the ileum and cardiac tissues, revealed that the activity of MO and citronellal might be related to the modification of either voltage-gated Ca2+ channels or muscarinic receptors. Mice locomotion, balance, and muscle strength were not impacted by the essential oil; however, its main constituent, citronellal, was found to exert a certain degree of muscle function inhibition. All these results suggest that the activity of MO essential oil arises from synergistic and/or antagonistic interactions of its constituents, and is not completely dependent on the oil's main constituent.
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•Melissa officinalis (MO) is utilized for different psyche-related disorders including anxiety.•MO essential oil and citronellal were tested in models involving anxiety-linked somatic symptoms.•MO essential oil and citronellal were found to inhibit spontaneous and induced ileum contractions.•They decreased heart rate and force of contraction but differently affected mice motor function.•They were both weak acetylcholine inhibitors but act via voltage-gated Ca2+ channels.
In this study, an NMR spectral analysis of the mixture of diastereomeric acetals, synthesized from 2,3-dihydrofurane and a racemic mixture of citronellol, was performed. 1H-NMR full spin analysis was ...achieved by manually adjusting ?H and J values (previously calculated using the Spartan software) to fit the experimentally available values, followed by further optimization using MestreNova software. The simulated 1H- and 13C-NMR spectra of individual diastereomers, as well as their superimposed and summed spectra, were compared with the obtained experimental spectra. Spin simulation of proton signals was particularly useful for the assignment of the diastereotopic protons of tetrahydrofuranyl moiety and diastereomer discrimination. The NMR spectral data of individual diastereomers ? chemical shifts, coupling constants, HMBC and NOESY interactions were systematized in appropriate tables and schemes. To the best of our knowledge, this is for the first time that the complete assignment of tetrahydrofuranyl moiety was performed, and the data obtained herein may be of great importance for the utilization of this protecting group in the future.
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