Characterisation of the metabolites of 1,8-cineole transferred into human milk: concentrations and ratio of enantiomers

Current use of medicinal plants for children's diseases among mothers in Southern Romania

There is a limited number of studies focusing on ethnomedical practices in children, particularly in Eastern Europe. Romania has a rich history of using medicinal plants in ethnopediatric care, and our objective was to identify the medicinal plants currently employed in treating childhood illnesses in the southern region of the country. Material and methods Our investigation used structured interviews, focusing on respondent demographics, local names of therapeutically employed herbs, the specific plant part(s) utilized, methods of preparation and administration, and local folk indications of taxa. A total of 326 mothers with children aged 0 to 18, hospitalized in the "Grigore Alexandrescu" Children Emergency Hospital Bucharest and residing in Southern Romania, were enrolled in the study. Use Value Citation Index (UVc), Informant Consensus Factor (Fic), and Fidelity Level (FL) were calculated. Results Twenty-five plants were identified for treating children's diseases in Southern Romania. The majority of informants resided in urban areas, and mothers primarily acquired knowledge from family members and healthcare professionals. The herbs most frequently employed were Mentha spp. (UV = 0.509) for diarrhea, Matricaria spp. (UV = 0.301) for skin infections (Fic = 0.99) and digestive diseases (Fic = 0.98), and Calendula officinalis L. (UV = 0.365) for skin diseases (Fic = 0.99). Less utilized were Raphanus raphanistrum subsp. sativus (L.) Domin in respiratory diseases, Prunus avium (L.) L. stalks in urinary tract ailments, Helianthus annuus L. in ear infections, Allium sativum L. in intestinal parasitosis, Viola tricolor L. in hives, Triticum aestivum L. in dermatitis and Allium ursinum L. as a tonic. In 184 cases herbal treatment was used in conjunction with conventional medications. Education level correlated with the number of employed plants and the variety of treated ailments, while residency (rural vs. urban) did not. Both residency and education influenced plant procurement methods: rural background and, surprisingly, higher education were linked to a preference for harvesting rather than purchasing plants. Conclusion Botanical remedies are still commonly used in the treatment of pediatric diseases in Southern Romania, although the variety of taxa seems reduced compared to the past. Further exploration is essential to unlock the maximum benefits of ethnopediatric practices.

Linalool, 1,8-Cineole, and Eugenol Transfer from a Curry Dish into Human Urine

SCOPE

For most substances, there are several routes of excretion from the human body. This study focuses on urinary excretion of dietary odorants and compares the results with previously obtained results on excretion into milk.

METHODS AND RESULTS

Lactating mothers (n = 18) are given a standardized curry dish and donate urine samples before and after the intervention. The odorants 1,8-cineole, linalool, cuminaldehyde, cinnamaldehyde, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, sotolone, eugenol, vanillin, and γ-nonalactone are quantitatively analyzed. A significant transition of up to 6 µg g-1 creatinine into urine is observed for linalool, 1,8-cineole, and eugenol. Maximum concentrations are reached 1.5 h after the intervention for 1,8-cineole and eugenol as well as 2.5 h after the intervention for linalool. Comparison with previous results reveals that the excretion pattern of odorants into urine is divergent from the one into milk. In a second intervention study (n = 6), excretion of phase II metabolites into urine is studied using β-glucuronidase treatment. Linalool and eugenol concentrations are 23 and 77 times higher after treatment than before treatment with β-glucuronidase, respectively.

CONCLUSION

The study demonstrates transition of linalool, 1,8-cineole, and eugenol from the diet into urine and excretion of glucuronides in the case of linalool, eugenol, and vanillin.

Safety and efficacy of a feed additive consisting of an essential oil from the aerial parts of Anethum graveolens L. (dill herb oil) for use in dogs and cats (FEFANA asbl)

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil obtained from the aerial parts of Anethum graveolens L. (dill herb oil), when used as a sensory additive (flavouring) in feed for dogs and cats. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that dill herb oil is safe at use levels in complete feed of 7 mg/kg for dogs and 5 mg/kg for cats. The additive under assessment should be considered as irritant to skin and eyes, and as a dermal and respiratory sensitiser. Since the aerial parts of A. graveolens and its preparations are recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Nasal Odorant Competitive Metabolism Is Involved in the Human Olfactory Process

Within the peripheral olfactory process, odorant metabolizing enzymes are involved in the active biotransformation of odorants, thus influencing the intensity and quality of the signal, but little evidence exists in humans. Here, we characterized the fast nasal metabolism of the food aroma pentane-2,3-dione in vivo and identified two resulting metabolites in the nasal-exhaled air, supporting the metabolizing role of the dicarbonyl/l-xylulose reductase. We showed in vitro, using the recombinant enzyme, that pentane-2,3-dione metabolism was inhibited by a second odorant (e.g., butanoic acid) according to an odorant-odorant competitive metabolic mechanism. Hypothesizing that such mechanism exists in vivo, pentane-2,3-dione, presented with a competitive odorant, both at subthreshold concentrations, was actually significantly perceived, suggesting an increase in its nasal availability. Our results, suggesting that odorant metabolizing enzymes can balance the relative detection of odorants in a mixture, in turn influencing the intensity of the signal, should be considered to better manage flavor perception in food.

1,8-cineole Ameliorates Right Ventricle Dysfunction Associated With Pulmonary Arterial Hypertension by Restoring Connexin 43 and Mitochondrial Homeostasis

For the first time, the present study unravels a cardiospecific therapeutic approach for Pulmonary Arterial Hypertension (PAH), a disease with a very poor prognosis and high mortality rates due to right ventricle dysfunction. We first established a new in vitro model of high-pressure-induced hypertrophy that closely resembles heart defects associated with PAH and validated our in vitro findings on a preclinical in vivo model of monocrotaline (MCT)-induced PAH. Our results showed the in vitro antihypertrophic effect of 1,8-cineole, a monoterpene widely found in several essential oils. Also, a decrease in RV hypertrophy and fibrosis, and an improvement in heart function in vivo was observed, when 1,8-cineole was applied topically. Furthermore, 1,8-cineole restored gap junction protein connexin43 distribution at the intercalated discs and mitochondrial functionality, suggesting it may act by preserving cardiac cell-to-cell communication and bioenergetics. Overall, our results point out a promising therapeutic compound that can be easily applied topically, thus paving the way for the development of effective cardiac-specific therapies to greatly improve PAH outcomes.

Dietary Piperine is Transferred into the Milk of Nursing Mothers

INTRODUCTION

The diet of breastfeeding mothers could bring nurslings into contact with flavor compounds putatively contributing to early sensory programming of the infant. The study investigates whether tastants from a customary curry dish consumed by mothers are detectable in their milk afterwards and can be perceived by the infant.

METHODS AND RESULTS

Sensory evaluation identifies pungency as the dominating taste impression of the curry dish. Its ingredients of chili, pepper, and ginger suggest the flavor compounds capsaicin, piperine, and 6-gingerol as analytical targets. Breastfeeding mothers are recruited for an intervention trial involving the consumption of the curry dish and subsequent collection of milk samples for flavor compound analysis. Targeted and untargeted mass spectrometric (MS)- investigations identify exclusively piperine as an intervention-derived compound in human milk. However, concentrations are below the human taste threshold.

CONCLUSION

Piperine from pepper-containing foods transfers into the mother's milk within 1 h and is delivered to the nursling. Concentrations of 50 and 200 nM of piperine are 70-350 times below the human taste threshold, but TRPV1 (Transient Receptor Potential Vanilloid-1 ion channel) desensitization through frequent exposure to sub-taste-threshold concentrations could contribute to an increased tolerance at a later age.

Can Eucalyptol Replace Antibiotics?

One of the primary reasons for the search for new antimicrobial agents is the increasing and spreading resistance of microorganisms to previously used drugs. This is particularly important in the case of rapidly progressing infections that require the rapid administration of an appropriately selected antibiotic. However, along with the administration of antibiotics, complications in the disease-weakened body may arise in the form of systemic mycoses, viral infections, and protozoan infections. Therefore, there is an increasing interest among researchers focusing on the use of naturally occurring terpenic compounds in stand-alone or combined therapies with antibiotics. In this publication, the aim of our work is to present the results of a literature review on the antimicrobial activity of eucalyptol.

Monoterpenes: current knowledge on food source, metabolism, and health effects

Monoterpenes, volatile metabolites produced by plants, are involved in the taste and aroma perception of fruits and vegetables and have been used for centuries in gastronomy, as food preservatives and for therapeutic purposes. Biological activities such as antimicrobial, analgesic and anti-inflammatory are well-established for some of these molecules. More recently, the ability of monoterpenes to regulate energy metabolism, and exert antidiabetic, anti-obesity and gut microbiota modulation activities have been described. Despite their promising health effects, the lack of reliable quantification of monoterpenes in food, hindered the investigation of their role as dietary bioactive compounds in epidemiological studies. Moreover, only few studies have documented the biotransformation of these compounds and identified the monoterpene metabolites with biological activity. This review presents up-to-date knowledge about the occurrence of monoterpenes in food, their bioavailability and potential role in the modulation of intermediate metabolism and inflammation, focusing on novel findings of molecular mechanisms, underlining research gaps and new avenues to be explored.

Chemical composition of Callistemon citrinus (Curtis) Skeels aerial part essential oil and its pharmacological applications, neurodegenerative inhibitory, and genotoxic efficiencies

Callistemon citrinus aerial part essential oil (CCEO) was analyzed for chemical compositions using GC/MS. Pharmacological activities such as neurodegenerative inhibitory, antioxidant, anti-inflammatory, antimicrobial, and acetylcholinesterase activities were evaluated using the standard methodologies. Genotoxicity was investigated using Allium cepa assay. GC/MS analysis identified 27 compounds; eucalyptol (55.40%) was the major component. Radical scavenging activity showed IC₅₀ value of 16.71 μg/mL. Protein denaturation assay showed IC₅₀ value of 21.19 μg/mL and 19.53μg/mL in protease inhibitor activity. MIC assay revealed antimicrobial potential of CCEO against microbial strains B. cereus at 2.00 mg/mL, S. typhimurium at 4.50 mg/mL, S. mutans at 2.50 mg/mL, C. albicans at 4.00 mg/mL, and S. cerevisiae at 4.50 mg/mL concentrations. Mitotic index value (MI) of CCEO showed negligible genotoxicity with MI 17.25% close to distilled water 18.22%. Acetylcholinesterase strong inhibitory activity of CCEO was observed from IC₅₀  = 6.335 μg/mL. CCEO could be a cheap and easy source for the extraction of the pure compound eucalyptol and possess various biological activities which increase its pharmacological value as well as its applicability in the field of flavor and fragrance industries. PRACTICAL APPLICATIONS: Eucalyptol is the major component of many pharmaceutical and food/flavor industries. The present investigation provides a new source for the isolation of pure compound eucalyptol in cost-effective way. Additionally, the essential oil could also be used for the pharmaceutical formulation of antioxidant, inflammation inhibitory, and neurodegenerative inhibitory drug preparation under the safety range concentration.

A literature survey of all volatiles from healthy human breath and bodily fluids: the human volatilome

This paper comprises an updated version of the 2014 review which reported 1846 volatile organic compounds (VOCs) identified from healthy humans. In total over 900 additional VOCs have been reported since the 2014 review and the VOCs from semen have been added. The numbers of VOCs found in breath and the other bodily fluids are: blood 379, breath 1488, faeces 443, milk 290, saliva 549, semen 196, skin 623 and urine 444. Compounds were assigned CAS registry numbers and named according to a common convention where possible. The compounds have been included in a single table with the source reference(s) for each VOC, an update on our 2014 paper. VOCs have also been grouped into tables according to their chemical class or functionality to permit easy comparison. Careful use of the database is needed, as a number of the identified VOCs only have level 2-putative assignment, and only a small fraction of the reported VOCs have been validated by standards. Some clear differences are observed, for instance, a lack of esters in urine with a high number in faeces and breath. However, the lack of compounds from matrices such a semen and milk compared to breath for example could be due to the techniques used or reflect the intensity of effort e.g. there are few publications on VOCs from milk and semen compared to a large number for breath. The large number of volatiles reported from skin is partly due to the methodologies used, e.g. by collecting skin sebum (with dissolved VOCs and semi VOCs) onto glass beads or cotton pads and then heating to a high temperature to desorb VOCs. All compounds have been included as reported (unless there was a clear discrepancy between name and chemical structure), but there may be some mistaken assignations arising from the original publications, particularly for isomers. It is the authors' intention that this work will not only be a useful database of VOCs listed in the literature but will stimulate further study of VOCs from healthy individuals; for example more work is required to confirm the identification of these VOCs adhering to the principles outlined in the metabolomics standards initiative. Establishing a list of volatiles emanating from healthy individuals and increased understanding of VOC metabolic pathways is an important step for differentiating between diseases using VOCs.

Diet-Induced Flavor Changes in Human Milk: Update and Perspectives

Dietary aroma transfer into human milk has been studied in many scenarios, including direct transmission and biotransformation. This perspective highlights recent research that focuses on the latter, with examples given in relation to 1,8-cineole and garlic-derived odorants. Three future directions are discussed, comprising (a) achieving a more comprehensive understanding of the chemical and physiological basis of aroma transfer into milk via pharmacological methods, advanced analytical techniques, and ecologically valid study designs, (b) assessing the bioactivity of odorants and their metabolites present in milk that are ingested by the infant, and (c) translating the insights gained on aroma transmission in relation to taste attributes and bioactive components of the maternal diet.

Artificial milk preference of newborn lambs is prenatally influenced by transfer of the flavor from the maternal diet to the amniotic fluid

The present study examined in lambs whether exposure to flavors derived from pregnant mother's diet and transferred to amniotic fluid (AF) could induce a preference for artificial milk containing one of these flavors. To test this hypothesis, cumin was added to the maternal diet in the last month of gestation. Preference for artificial milk containing p-cymene, one of the chemosensory compounds of cumin, was tested within the first two days after birth in maternally deprived lambs born from mothers fed a cumin-flavored diet (Cumin group), or an unflavored diet (Control group). Aromatic profile of AF from cumin-fed mothers was analyzed by GC-MS/MS to determine whether p-cymene could be detected. While the control group avoided the flavored artificial milk on day 1, the Cumin group did not and showed a preference for the cumin-scented formula on day 2. GC-MS/MS profile of AF revealed that four of the main volatile cumin compounds, p-cymene, p-cymenene, β-pinene and γ-terpinene were present in variable amounts in all samples, p-cymene being the most frequently detected. These findings indicate that newborn lambs can memorize flavors from the mother's diet present in AF and that prenatal experience influences their preference for an artificial milk containing one specific flavor.

[Breastfeeding and potential sensory imprinting]

Breastmilk provides well-known nutritional and functional advantages and in addition a greater sensory variety as compared to infant formula. Volatile and soluble sensory components from the mother's diet are transmitted prenatally into the amniotic fluid and postnatally into breastmilk and can be detected by the fetus and infant. Breastfeeding is suggested to serve as a bridge from prenatal flavor experiences to the varied sensory world of complementary feeding and family diet afterwards. Nevertheless definite data to prove this plausible assumption are still missing. Randomized intervention trials with a necessary long-term follow-up are difficult to implement and rarely achieved. Lasting effects of early sensory experiences have so far been demonstrated mostly in the first year of life and by applying intensive sensory interventions, which are hardly possible in a habitual maternal diet. The practical relevance of a potential sensory imprinting by breastfeeding still remains open. Nevertheless a varied diet in pregnancy and lactation can be recommended not only for nutritional reasons but also from a hedonic sensory perspective.

Optical quantum weak measurement coupled with UV spectrophotometry for sensitively and non-separatedly detecting enantiopurity

Based on the theories of quantum weak measurement, we built a set of linear common-path optical weak measurement systems in frequency domain for detecting chiral molecules. The polarization resolution with this system to detect the optical rotation of chirality molecules is nearly two orders of magnitude higher than that of conventional polarizers. Combined with ultraviolet spectroscopy, the purity of the proline enantiomers mixture was detected. The purity resolution can reach to 0.14%, which is comparable to the liquid chromatography. Weak measurement combined with ultraviolet spectroscopy to non-separatedly detect the purity of chiral enantiomers has great application potential in the pharmaceutical industry.

Chemical Composition and Antimicrobial Activities of the Essential Oil From Salvia mirzayanii Leaves

Resistance of many pathogens to available drugs is a global challenge and is leading to growing interest in natural alternative products. In this study, chemical composition and in vitro antibacterial and antifungal activities of the essential oil from Salvia mirzayanii were investigated. The chemical constituents of essential oil from S mirzayanii were analyzed by gas chromatography–mass spectrometry. The antimicrobial activity was determined by broth microdilution. The main identified compounds were 1,8-cineole (41.2 ± 1.3%), linalool acetate (11.0 ± 0.5%), and α-terpinyl acetate (6.0 ± 0.4%) (mL of essential oil/g of plant material). The MIC₉₅ were 0.03 to 0.5 µL/mL and 16 to 128 µL/mL for gram-positive and gram-negative bacteria, respectively. These results indicated that Salvia mirzayanii essential oil significantly inhibited the growth of standard and clinically isolated tested yeasts by MIC₅₀ 0.03 to 1 µL/mL. Potent antibacterial and antifungal activities of Salvia mirzayanii essential oil may be considered in future study, particularly against antibiotic-resistant cases.

Transient Receptor Potential Cation Channel Subfamily M Member 8 channels mediate the anti-inflammatory effects of eucalyptol

BACKGROUND AND PURPOSE

Eucalyptol (1,8-cineol), the major ingredient in the essential oil of eucalyptus leaves and other medicinal plants, has long been known for its anti-inflammatory properties. Eucalyptol interacts with the TRP cation channels among other targets, but it is unclear which of these mediates its anti-inflammatory effects.

EXPERIMENTAL APPROACH

Effects of eucalyptol were compared in wild-type and TRPM8 channel-deficient mice in two different models: footpad inflammation elicited by complete Freund's adjuvant (CFA) and pulmonary inflammation following administration of LPS. Oedema formation, behavioural inflammatory pain responses, leukocyte infiltration, enzyme activities and cytokine and chemokine levels were measured.

KEY RESULTS

In the CFA model, eucalyptol strongly attenuated oedema and mechanical allodynia and reduced levels of inflammatory cytokines (IL-1β, TNF-α and IL-6), effects comparable with those of ibuprofen. In the LPS model of pulmonary inflammation, eucalyptol treatment diminished leukocyte infiltration, myeloperoxidase activity and production of TNF-α, IL-1β, IFN-γ and IL-6. Genetic deletion of TRPM8 channels abolished the anti-inflammatory effects of eucalyptol in both models. Eucalyptol was at least sixfold more potent on human, than on mouse TRPM8 channels. A metabolite of eucalyptol, 2-hydroxy-1,8-cineol, also activated human TRPM8 channels.

CONCLUSION AND IMPLICATIONS

Among the pharmacological targets of eucalyptol, TRPM8 channels were essential for its anti-inflammatory effects in mice. Human TRPM8 channels are more sensitive to eucalyptol than rodent TRPM8 channels explaining the higher potency of eucalyptol in humans. Metabolites of eucalyptol could contribute to its anti-inflammatory effects. The development of more potent and selective TRPM8 agonists may yield novel anti-inflammatory agents.

Odor qualities and thresholds of physiological metabolites of 1,8-cineole as an example for structure-activity relationships considering chirality aspects

The present study aimed at analyzing the odor properties of a group of physiological human metabolites of the odorant 1,8-cineole: 2,3-dehydro-, α2,3-epoxy-, α/β2-hydroxy-, α3-hydroxy-, 4-hydroxy-, 7-hydroxy-, 9-hydroxy-, 2-oxo-, and 3-oxo-1,8-cineole. These metabolites constitute a group of structurally closely related molecules, which differ mainly in nature and position of O-containing functional groups. They thus offer the possibility to correlate odor properties with molecular structure, i.e., to establish structure-odor relationships of compounds that are biologically generated from a potent odorant as parent substance. Generally, the metabolites preserved the eucalyptus-like odor quality of 1,8-cineole but showed additional odor notes such as sweet, citrus-like, plastic-like, earthy, musty, and faecal, which made them distinguishable. The individual enantiomers of chiral molecules also exhibited different odors. With the exception of 2,3-dehydro-1,8-cineole, all metabolites showed a highly decreased odor threshold in comparison to 1,8-cineole. The determination of odor qualities and odor thresholds was accomplished by gas chromatography/olfactometry (GC/O) on achiral and chiral GC capillaries. The results were correlated with common theories on structure-odor relationships.