Absinthe—A Review

Acute Kidney Injury Following the Ingestion of a Medicinal Plants' Mixture: A Case Report

Acute renal failure secondary to medicinal plants is common in countries where the use of traditional phytotherapy is preponderant. Although the nephrotoxic potentials of some herbal preparations have been well characterized, the use of many medicinal plants is still considered largely safe, often relying on weak evidence. Here, we report the case of a 17-year-old patient with severe acute renal failure, associated to an esophagitis with erosive gastritis as well as an inflammatory anemia, with no obvious etiology. After ruling out any other plausible explanation, the syndrome was attributed to the chronic intake of a mixture of three medicinal plants, previously unknown to be nephrotoxic: Artemisia absinthium, Marrubium vulgare, and Centaurium erythraea. A histological examination of a renal biopsy sample revealed an aspect of interstitial nephritis without antibody deposits. To our knowledge, this is the first reported case of acute kidney injury related to the consumption of these three plants and prompts further studies to carefully assess the safety of traditional medicinal products based on these plants.

Artemisia spp. Essential Oils: From Their Ethnobotanical Use to Unraveling the Microbiota Modulation Potential

BACKGROUND

The 2015 Nobel Prize in Medicine, awarded for the discovery of artemisinin in Artemisia annua, reignited interest in aromatic plants, including Artemisia absinthium L. This article delves into the historical, ethnopharmacological and medicinal significance of A. absinthium, examining its bitter taste noted since ancient Greek times and its association with medicinal properties throughout history. Despite being banned in the 20th century due to perceived health risks; recent research has led to the reconsideration of A. absinthium's potential applications. This study focuses on the prebiotic efficacy of essential oils (EOs) from two Artemisia species: A. absinthium and A. annua.

MATERIALS AND METHODS

A broth microdilution test, growth curve test and in vivo models were used to study the impact of low doses (from 0.5% v/v to 0.00048 v/v) of Artemisia spp-EO on the three probiotic strains (Lactobacillus, Lactobacillus casei and Saccharomyces boulardii).

RESULTS

These essential oils, when used in minimal concentrations (lower than 0.06% v/v), are safe and exhibit prebiotic effects on major probiotic strains, supporting the traditional culinary use of Artemisia spp.

CONCLUSION

This research opens avenues for potential applications in the food industry, emphasizing the need for further exploration into the prebiotic properties of Artemisia spp-EOs and their influence on the microbiota.

Comparative Analysis of Active Ingredients and Potential Bioactivities of Essential Oils from Artemisia argyi and A. verlotorum

Artemisia argyi H. Lév. and Vaniot is a variety of Chinese mugwort widely cultured in central China. A. verlotorum Lamotte, another variety of Chinese mugwort, has been used in the southern region of China since ancient times. Despite their similar uses in traditional medicine, little is known about the differences in their active ingredients and potential benefits. Herein, the chemical compositions of the essential oils (EOs) from both varieties were analyzed using chromatography-mass spectrometry (GC-MS). A series of databases, such as the Traditional Chinese Medicine Systems Pharmacology database (TCMSP), SuperPred database and R tool, were applied to build a networking of the EOs. Our results revealed significant differences in the chemical compositions of the two Artemisia EOs. However, we found that they shared similar ingredient-target-pathway networking with diverse bioactivities, such as neuroprotective, anti-cancer and anti-inflammatory. Furthermore, our protein connection networking analysis showed that transcription factor p65 (RELA), phosphatidylinositol 3-kinase regulatory subunit alpha (PIK3R1) and mitogen-activated protein kinase 1 (MAPK1) are crucial for the biological activity of Artemisia EOs. Our findings provided evidence for the use of A. verlotorum as Chinese mugwort in southern China.

Food in painting: From dietetics to symbolism

Since the Antiquity, many artists have represented food in their paintings. Most of them are European painters originating essentially from the Southern Europe. There is no doubt that the Greco-Roman culture and Christianity - that became the official religion of the Roman Empire - influenced these artists since two millenars. Throughout the painting's production, we have tried to discover information of the dietary habits at a particular period, to scrutinize some dietary recommendations but also to detect the symbolic dimension of the represented foods.

Artemisia Species with High Biological Values as a Potential Source of Medicinal and Cosmetic Raw Materials

Artemisia species play a vital role in traditional and contemporary medicine. Among them, Artemisia abrotanum, Artemisia absinthium, Artemisia annua, Artemisia dracunculus, and Artemisia vulgaris are the most popular. The chemical composition and bioactivity of these species have been extensively studied. Studies on these species have confirmed their traditional applications and documented new pharmacological directions and their valuable and potential applications in cosmetology. Artemisia ssp. primarily contain sesquiterpenoid lactones, coumarins, flavonoids, and phenolic acids. Essential oils obtained from these species are of great biological importance. Extracts from Artemisia ssp. have been scientifically proven to exhibit, among others, hepatoprotective, neuroprotective, antidepressant, cytotoxic, and digestion-stimulating activities. In addition, their application in cosmetic products is currently the subject of several studies. Essential oils or extracts from different parts of Artemisia ssp. have been characterized by antibacterial, antifungal, and antioxidant activities. Products with Artemisia extracts, essential oils, or individual compounds can be used on skin, hair, and nails. Artemisia products are also used as ingredients in skincare cosmetics, such as creams, shampoos, essences, serums, masks, lotions, and tonics. This review focuses especially on elucidating the importance of the most popular/important species of the Artemisia genus in the cosmetic industry.

Artemisia spp.: An Update on Its Chemical Composition, Pharmacological and Toxicological Profiles

Artemisia plants are traditional and ethnopharmacologically used to treat several diseases and in addition in food, spices, and beverages. The genus is widely distributed in all continents except the Antarctica, and traditional medicine has been used as antimalarial, antioxidant, anticancer, antinociceptive, anti-inflammatory, and antiviral agents. This review is aimed at systematizing scientific data on the geographical distribution, chemical composition, and pharmacological and toxicological profiles of the Artemisia genus. Data from the literature on Artemisia plants were taken using electronic databases such as PubMed/MEDLINE, Scopus, and Web of Science. Selected papers for this updated study included data about phytochemicals, preclinical pharmacological experimental studies with molecular mechanisms included, clinical studies, and toxicological and safety data. In addition, ancient texts and books were consulted. The essential oils and phytochemicals of the Artemisia genus have reported important biological activities, among them the artemisinin, a sesquiterpene lactone, with antimalarial activity. Artemisia absinthium L. is one of the most famous Artemisia spp. due to its use in the production of the absinthe drink which is restricted in most countries because of neurotoxicity. The analyzed studies confirmed that Artemisia plants have many traditional and pharmacological applications. However, scientific data are limited to clinical and toxicological research. Therefore, further research is needed on these aspects to understand the full therapeutic potential and molecular pharmacological mechanisms of this medicinal species.

Toxicity of Selected Monoterpenes and Essential Oils Rich in These Compounds

Monoterpenes make up the largest group of plant secondary metabolites. They can be found in numerous plants, among others, the Lamiaceae family. The compounds demonstrate antioxidative, antibacterial, sedative and anti-inflammatory activity, hence, they are often employed in medicine and pharmaceuticals. Additionally, their fragrant character is often made use of, notably in the food and cosmetic industries. Nevertheless, long-lasting studies have revealed their toxic properties. This fact has led to a detailed analysis of the compounds towards their side effects on the human organism. Although most are safe for human food and medical applications, there are monoterpene compounds that, in certain amounts or under particular circumstances (e.g., pregnancy), can cause serious disorders. The presented review characterises in vitro and in vivo, the toxic character of selected monoterpenes (α-terpinene, camphor, citral, limonene, pulegone, thujone), as well as that of their original plant sources and their essential oils. The selected monoterpenes reveal various toxic properties among which are embryotoxic, neurotoxic, allergenic and genotoxic. It is also known that the essential oils of popular plants can also reveal toxic characteristics that many people are unaware of.

Neuropsychopharmacological profiling of scoparone in mice

Scoparone (6,7-dimethoxycoumarin) is a simple coumarin from botanical drugs of Artemisia species used in Traditional Chinese Medicine and Génépi liquor. However, its bioavailability to the brain and potential central effects remain unexplored. We profiled the neuropharmacological effects of scoparone upon acute and subchronic intraperitoneal administration (2.5-25 mg/kg) in Swiss mice and determined its brain concentrations and its effects on the endocannabinoid system (ECS) and related lipids using LC-ESI-MS/MS. Scoparone showed no effect in the forced swimming test (FST) but, administered acutely, led to a bell-shaped anxiogenic-like behavior in the elevated plus-maze test and bell-shaped procognitive effects in the passive avoidance test when given subchronically and acutely. Scoparone rapidly but moderately accumulated in the brain (Cmax < 15 min) with an apparent first-order elimination (95% eliminated at 1 h). Acute scoparone administration (5 mg/kg) significantly increased brain arachidonic acid, prostaglandins, and N-acylethanolamines (NAEs) in the FST. Conversely, subchronic scoparone treatment (2.5 mg/kg) decreased NAEs and increased 2-arachidonoylglycerol. Scoparone differentially impacted ECS lipid remodeling in the brain independent of serine hydrolase modulation. Overall, the unexpectedly potent central effects of scoparone observed in mice could have toxicopharmacological implications for humans.

Evaluation of the phytotoxic effect of the essential oil from Artemisia absinthium

The chemical profile and the phytotoxicity of Artemisia absinthium essential oil (EO) were investigated to evaluate its potential value as a biopesticide for food safety purposes. A total of 54 compounds were identified in A. absinthium EO, with the most abundant constituents being eucalyptol (25.59%), linalool (11.99%), and β-myrcene (10.05%). The EO, linalool, and a mixture of three major components exhibited potent suppressive activity against four receiver species; however, eucalyptol and β-myrcene showed a much weaker effect. Bioassay-guided fractionation led to the isolation of linalool as the major active compound responsible for the EO's phytotoxicity. Subsequent scanning electron microscopy (SEM) analysis revealed that linalool significantly inhibited root-hair formation and metaxylem development. This is the first report on the determination of linalool as the major active phytotoxic compound in A. absinthium EO, as well as the elucidation of its mechanism of phytotoxicity from the perspective of root structure changes in the receiver species. Our results suggest that both the EO and its major constituents have potential value as environmentally friendly herbicides.

Examining the Temperature Dependence of Louche Formation in Absinthe

Absinthe is an anise-flavored alcohol that is typically served by adding cold water to form a cloudy green louche, similar to the cloudy white louche of ouzo. This microemulsion formation, due to the competing interactions within the oil-alcohol-water system, has been termed the ouzo effect. Previous work has examined the ternary oil-alcohol-water phase diagram in ouzo and limoncello. Additional work has also characterized the droplet size and stability of microemulsions in ouzo, limoncello, and pastis. However, less work has been done to examine the effect of temperature on louche formation despite the fact that the louche is traditionally formed by adding ice cold water. This work demonstrates that both the maximum turbidity and the fraction of alcohol at maximum turbidity are temperature-dependent. The louche formation can be fit with a logistic curve, and the resulting fit parameters are linear with temperature. Optical images show that the increased turbidity correlates with an increase in the number of droplets in the microemulsion.

Monoterpenes: Essential Oil Components with Valuable Features

Medicinal plants have a wide range of secondary metabolites including monoterpene. These volatile compounds are the main components of essential oils, belonging to the isoprenoid group and possessing valuable features for plants and humans. This review provides comprehensive information on chemical structures and classification of monoterpenes. It describes their biosynthesis pathways and introduces plant families and species rich in noteworthy monoterpenes. Bio-activities, pharmacological and pesticide effects as well as their mechanism of action are reported. Applications of these compounds in various industries are also included.

Research Advances on Health Effects of Edible Artemisia Species and Some Sesquiterpene Lactones Constituents

The genus Artemisia, often known collectively as "wormwood", has aroused great interest in the scientific community, pharmaceutical and food industries, generating many studies on the most varied aspects of these plants. In this review, the most recent evidence on health effects of edible Artemisia species and some of its constituents are presented and discussed, based on studies published until 2020, available in the Scopus, Web of Sciences and PubMed databases, related to food applications, nutritional and sesquiterpene lactones composition, and their therapeutic effects supported by in vivo and clinical studies. The analysis of more than 300 selected articles highlights the beneficial effect on health and the high clinical relevance of several Artemisia species besides some sesquiterpene lactones constituents and their derivatives. From an integrated perspective, as it includes therapeutic and nutritional properties, without ignoring some adverse effects described in the literature, this review shows the great potential of Artemisia plants and some of their constituents as dietary supplements, functional foods and as the source of new, more efficient, and safe medicines. Despite all the benefits demonstrated, some gaps need to be filled, mainly related to the use of raw Artemisia extracts, such as its standardization and clinical trials on adverse effects and its health care efficacy.

Visiting the 'green fairy': Absinthe-tourism - A potential challenge for travel medicine?

Increasingly, travellers are looking for novel and unusual tourism experiences. Local produce, such as wine and food, has long been a strong visitor magnet. The search for pleasurable experiences has extended to substances that may be illegal at home, or to those surrounded by mystery. Travel medicine needs to be aware of new trends in tourism, especially if they involve substances with potential health risks, so that appropriate travel health advice can be given including the consideration of potential adverse reactions with current medications or pre-existing conditions. This article introduces a relatively new trend, 'absinthe-tourism', the mysterious drink itself, its flamboyant history and the escalating health issues in the 19th century that finally led to its ban in many countries. Absinthe is now freely available from reputable distilleries. Today, medical concern lies rather with unscrupulous suppliers on the internet, high alcohol content and adulterations. Until evidence suggests otherwise, there may be no concern for healthy travellers on the 'fairy-trail'.

Artemisia absinthium L.-Importance in the History of Medicine, the Latest Advances in Phytochemistry and Therapeutical, Cosmetological and Culinary Uses

Artemisia absinthium-wormwood (Asteraceae)-is a very important species in the history of medicine, formerly described in medieval Europe as "the most important master against all exhaustions". It is a species known as a medicinal plant in Europe and also in West Asia and North America. The raw material obtained from this species is Absinthii herba and Artemisiae absinthii aetheroleum. The main substances responsible for the biological activity of the herb are: the essential oil, bitter sesquiterpenoid lactones, flavonoids, other bitterness-imparting compounds, azulenes, phenolic acids, tannins and lignans. In the official European medicine, the species is used in both allopathy and homeopathy. In the traditional Asian and European medicine, it has been used as an effective agent in gastrointestinal ailments and also in the treatment of helminthiasis, anaemia, insomnia, bladder diseases, difficult-to-heal wounds, and fever. Today, numerous other directions of biological activity of the components of this species have been demonstrated and confirmed by scientific research, such as antiprotozoal, antibacterial, antifungal, anti-ulcer, hepatoprotective, anti-inflammatory, immunomodulatory, cytotoxic, analgesic, neuroprotective, anti-depressant, procognitive, neurotrophic, and cell membrane stabilizing and antioxidant activities. A. absinthium is also making a successful career as a cosmetic plant. In addition, the importance of this species as a spice plant and valuable additive in the alcohol industry (famous absinthe and vermouth-type wines) has not decreased. The species has also become an object of biotechnological research.

Anti-inflammatory Activity of Absinthin and Derivatives in Human Bronchoepithelial Cells

Bitter taste receptors (hTAS2R) are expressed ectopically in various tissues, raising the possibility of a pharmacological exploitation. This seems of particular relevance in airways, since hTAS2Rs are involved in the protection of the aerial tissues from infections and in bronchodilation. The bis-guaianolide absinthin (1), one of the most bitter compounds known, targets the hTAS2R46 bitter receptor. Absinthin (1), an unstable compound, readily turns into anabsinthin (2) with substantial retention of the bitter properties, and this compound was used as a starting material to explore the chemical space around the bis-guaianolide bitter pharmacophore. Capitalizing on the chemoselective opening of the allylic lactone ring, the esters 3 and 4, and the nor-azide 6 were prepared and assayed on human bronchoepithelial (BEAS-2B) cells expressing hTAS2R46. Anti-inflammatory activity was evaluated by measuring the expression of MUC5AC, iNOS, and cytokines, as well as the production of superoxide anion, qualifying the methyl ester 3 as the best candidate for additional studies.

Umbelliprenin as a novel component of the phytochemical pool from Artemisia spp

Plants belonging to Artemisia spp. are known to biosynthesize a wide panel of 3,3-dimethylallyl- and sesquiterpenyl- substituted coumarins. In this short communication we applied a novel extraction methodology based on the use of subcritical butane under a counter-current mode to further characterize the presence of selected biologically active oxyprenylated phenylpropanoids, namely coumarins and ferulic acid derivatives, in extracts deriving from aerial parts of Artemisia vulgaris L. (commonly known as "common mugwort") (Asteraceae). In the mean time, we assessed the efficiency of the above mentioned extractive methodology with other routes like maceration and ultrasounds and microwaves-based methods using absolute EtOH as the solvents. UHPLC analysis coupled to UV/Vis detection revealed that, among the 5 pure chemical standard assayed, only umbelliprenin (7-farnesyloxycoumarin) was recorded, while boropinic acid, 4'-geranyloxyferulic acid, 7-isopentenyloxycoumarin, and auraptene were not detected. The best extractive yield (0.18 %) was obtained after extaction with subcritical butane. The presence of umbelliprenin in Artemisia plant species has been reported herein for the first time. This coumarin may represent the biosynthetic precursors of sesquiterpenyloxycoumarins with more complex structures typically found in this genus.

Toxicity of secondary metabolites

Secondary metabolites, commonly referred to as natural products, are produced by living organisms and usually have pharmacological or biological activities. Secondary metabolites are the primary source for the discovery of new drugs. Furthermore, secondary metabolites are also used as food preservatives, biopesticides or as research tools. Although secondary metabolites are mainly used by their beneficial biological activity, the toxicity of some of them may limit their use. The toxicity assessment of any compound that is prone to be used in direct contact with human beings is of vital importance. There is a vast spectrum of experimental methods for toxicity evaluation, including in vitro and in vivo methodologies. In this work, we present an overview of the different sources, bioactivities, toxicities and chemical classification of secondary metabolites, followed by a sketch of the role of toxicity assessment in drug discovery and agrochemistry.

Identification and Quantification of Thujone in a Case of Poisoning Due to Repeated Ingestion of an Infusion of Artemisia Vulgaris L

Plants of the Artemisia genus are used worldwide as ingredients of botanical preparations. This paper describes the case of a 49-year-old man admitted to the emergency room at a Zurich hospital in a manic state after the ingestion of 1 L of an infusion of Artemisia vulgaris. Two monoterpenic ketones, α- and β-thujone, are present in various concentrations in Artemisia spp., but adverse effects have previously been associated only with essential oil from Artemisia absinthium and attributed to the inhibition of gamma-aminobutyric acid receptors, with consequent excitation and convulsions. The aim of this work was to examine and quantify the possible presence of thujone in the patient's serum and urine. A High Performance Liquid Chromatography (HPLC) method with isocratic separation and fluorescence detection (FLD) was set up and validated. Serum thujone concentrations were found to be 27.7 ± 3.48 μg/mL at day 0 and 24.1 ± 0.15 μg/mL on day 1. Results were confirmed by a gas chromatography with flame ionization detection (FID). Poisoning due to thujone was thus confirmed, suggesting four possible scenarios: (1) an unusually high concentration of thujone in the A. vulgaris ingested; (2) chronic exposure as the cause of the poisoning; (3) low metabolic efficiency of the patient; (4) contamination or adulteration of the plant material with other Artemisia spp., for example, A. absinthium.

PRACTICAL APPLICATION

These results could aid research in the field of adverse effects of botanicals, lead to better understanding and management of similar cases of poisoning, and promote more informed use of natural products.

Absinthin attenuates LPS-induced ALI through MIP-1α-mediated inflammatory cell infiltration

Acute lung injury (ALI) is characterized by severe lung inflammation, and anti-inflammatory treatment is proposed to be a pertinent therapeutic strategy for the disease. Absinthin is a triterpene, extracted from a Chinese herb, with anti-inflammatory properties. The aim of this study was to evaluate whether absinthin can attenuate ALI in a mouse model of lung injury. Mice were treated with various concentrations (20 mg/kg, 40 mg/kg, and 80mg/kg) of absinthin, and lipopolysaccharide (LPS) to induce ALI. We found that the administration of absinthin relieved LPS-induced acute lung injury, as suggested by reduced histological scores, wet-to-dry ratio, myeloperoxidase activity, and accumulation of inflammatory cells in lung bronchoalveolar lavage fluid. Moreover, we demonstrated that absinthin significantly enhanced the expression of matrix metalloproteinase-8 (MMP-8); this effect could inhibit the accumulation of inflammatory cells in lung tissues through a mechanism dependent on MMP-8-mediated inactivation of macrophage inflammatory protein-1α. Therefore, we propose that absinthin is a promising novel therapeutic candidate for the treatment of ALI.

Himalayan Aromatic Medicinal Plants: A Review of their Ethnopharmacology, Volatile Phytochemistry, and Biological Activities

Aromatic plants have played key roles in the lives of tribal peoples living in the Himalaya by providing products for both food and medicine. This review presents a summary of aromatic medicinal plants from the Indian Himalaya, Nepal, and Bhutan, focusing on plant species for which volatile compositions have been described. The review summarizes 116 aromatic plant species distributed over 26 families.

Toxicokinetics of α-thujone following intravenous and gavage administration of α-thujone or α- and β-thujone mixture in male and female F344/N rats and B6C3F1 mice

Plants containing thujone have widespread use and hence have significant human exposure. α-Thujone caused seizures in rodents following gavage administration. We investigated the toxicokinetics of α-thujone in male and female F344/N rats and B6C3F1 mice following intravenous and gavage administration of α-thujone or a mixture of α- and β-thujone (which will be referred to as α,β-thujone). Absorption of α-thujone following gavage administration was rapid without any dose-, species-, sex- or test article-related effect. Absolute bioavailability of α-thujone following administration of α-thujone or α,β-thujone was generally higher in rats than in mice. In rats, females had higher bioavailability than males following administration of either test article although a sex difference was not observed in mice. Cmax and AUC∞ increased greater than proportional to the dose in female rats following administration of α-thujone and in male and female mice following administration of α,β-thujone suggesting possible saturation of elimination kinetics with increasing dose. Dose-adjusted AUC∞ for male and female rats was 5- to 15-fold and 3- to 24-fold higher than mice counterparts following administration of α-thujone and α,β-thujone, respectively (p-value<0.0001 for all comparisons). Following both intravenous and gavage administration, α-thujone was distributed to the brains of rats and mice with females, in general, having higher brain:plasma ratios than males. These data are in support of the observed toxicity of α-thujone and α,β-thujone where females were more sensitive than males of both species to α-thujone-induced neurotoxicity. In general there was no difference in toxicokinetics between test articles when normalized to α-thujone concentration.

Optimisation of ultrasonic-assisted extraction of antioxidant compounds from Artemisia absinthium using response surface methodology

Response surface methodology was used to optimise experimental conditions for ultrasonic-assisted extraction of phenolic compounds from Artemisia absinthium. The central composite design was employed, the extracts were characterised by the determination of total phenolic content and antioxidant capacity. The total phenolic contents of extracts were determined by Folin method and also total antioxidant capacities of extracts were determined by ABTS and CUPRAC methods. The phenolic compounds of A. absinthium at optimum extraction conditions were determined by HPLC-DAD. The optimum conditions were determined as HCl concentration between 0.41 and 0.44mol/L, methanol volume between 55% and 59% (v/v), extraction temperature between 64 and 70°C, extraction time between 101 and 107min. The experimental values agreed with those predicted within a 95% confidence level, thus indicating the suitability of response surface methodology in optimising the ultrasound-assisted extraction of phenolic compounds from A. absinthium.

Identification of genes in Thuja plicata foliar terpenoid defenses

Thuja plicata (western redcedar) is a long-lived conifer species whose foliage is rarely affected by disease or insect pests, but can be severely damaged by ungulate browsing. Deterrence to browsing correlates with high foliar levels of terpenoids, in particular the monoterpenoid α-thujone. Here, we set out to identify genes whose products may be involved in the production of α-thujone and other terpenoids in this species. First, we generated a foliar transcriptome database from which to draw candidate genes. Second, we mapped the storage of thujones and other terpenoids to foliar glands. Third, we used global expression profiling to identify more than 600 genes that are expressed at high levels in foliage with glands, but can either not be detected or are expressed at low levels in a natural variant lacking foliar glands. Fourth, we used in situ RNA hybridization to map the expression of a putative monoterpene synthase to the epithelium of glands and used enzyme assays with recombinant protein of the same gene to show that it produces sabinene, the monoterpene precursor of α-thujone. Finally, we identified candidate genes with predicted enzymatic functions for the conversion of sabinene to α-thujone. Taken together, this approach generated both general resources and detailed functional characterization in the identification of genes of foliar terpenoid biosynthesis in T. plicata.

Cytotoxicity and genotoxicity of coronaridine from Tabernaemontana catharinensis A.DC in a human laryngeal epithelial carcinoma cell line (Hep-2)

Cancer has become a major public health problem worldwide and the number of deaths due to this disease is increasing almost exponentially. In the constant search for new treatments, natural products of plant origin have provided a variety of new compounds to be explored as antitumor agents. Tabernaemontana catharinensis is a medicinal plant that produces alkaloids with expressive antitumor activity, such as heyneanine, coronaridine and voacangine. The aim of present study was firstly to screen the cytotoxic activity of the indole alkaloids heyneanine, coronaridine and voacangine against HeLa (human cervix tumor), 3T3 (normal mouse embryo fibroblasts), Hep-2 (human laryngeal epithelial carcinoma) and B-16 (murine skin) cell lines by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide); and secondly to analyze the apoptotic activity, cell membrane damage and genotoxicity of the compound that showed the best cytotoxic activity against the tumor cell lines tested. Coronaridine was the one that exhibited greater cytotoxic activity in the laryngeal carcinoma cell line Hep-2 (IC50 = 54.47 μg/mL) than the other alkaloids tested (voacangine IC50 = 159.33 g/mL, and heyneanine IC50 = 689.45 μg/mL). Coronaridine induced apoptosis in cell lines 3T3 and Hep-2, even at high concentrations. The evaluation of genotoxicity by comet assay showed further that coronaridine caused minimal DNA damage in the Hep-2 tumor cell line, and the LDH test showed that it did not affect the plasma membrane. These results suggest that further investigation of coronaridine as an antitumor agent has merit.

Thujone and thujone-containing herbal medicinal and botanical products: toxicological assessment

Thujone, a major component of the notoriously famous absinthe drink, is neurotoxic, although the current view rather downgrades its risk to humans. In animal studies, thujone inhibits the gamma-aminobutyric acid A (GABA(A)) receptor causing excitation and convulsions in a dose-dependent manner, although there are uncertainties about the doses required in humans. Toxicity of thujone has been extensively studied. Neurotoxicity is the principal toxic outcome in acute and chronic studies. There is some equivocal evidence of carcinogenicity in rats. Metabolism of thujone has been elucidated both in vitro and in vivo in several species and in vitro in human liver preparations. CYP2A6 is the principal metabolic enzyme, followed by CYP3A4 and, to a lesser extent, CYP2B6. CYP-associated metabolism may give rise to some potential pharmacogenetic and metabolic interaction consequences. Although the data base for determining exposure limits is of variable usefulness, the best estimates for allowable daily intakes via herbal preparations and diet are of the order of 3-7 mg/day. There are still important gaps in the knowledge required to assess thujone toxicity, the most important ones being human dose-concentration-effect relationships including the elucidation of bioavailability, and the actual toxicological consequences of potential pharmacogenetic variations and environmental factors.

Rapid Determination of Total Thujone in Absinthe Using 1H NMR Spectroscopy

1H NMR spectroscopy is utilized to quantify total thujone (sum of α- and β-isomers) in absinthe. For sample preparation, a simple dilution with buffer is required. Thujone produces a distinct peak of the CH2 group in the cyclopentanone moiety in the 2.13–2.11 ppm range. No overlap with other typical constituents such as anethole or fenchone occurs. The detection limit of 0.3 mg/L is adequate to control the EU maximum limit. The relative standard deviation was 6%, and linearity was observed from 1 to 100 mg/L. Applicability was proven by analysis of 69 authentic absinthes. The correlation between NMR and our previous method consisting of liquid-liquid extraction followed by GC/MS was significant (P<0.0001,R=0.93). The simple and cheap NMR method can be used for rapid screening of absinthes for total thujone content while chromatographic techniques are recommended for more specific (α- and β-thujone isomers) analysis if required.

Determination of the biologically active flavour substances thujone and camphor in foods and medicines containing sage (Salvia officinalis L.)

Background

The sage plant Salvia officinalis L. is used as ingredient in foods and beverages as well as in herbal medicinal products. A major use is in the form of aqueous infusions as sage tea, which is legal to be sold as either food or medicine. Sage may contain two health relevant substances, thujone and camphor. The aim of this study was to develop and validate an analytical methodology to determine these active principles of sage and give a first overview of their concentrations in a wide variety of sage foods and medicines.

Results

A GC/MS procedure was applied for the analysis of α- and β-thujone and camphor with cyclodecanone as internal standard. The precision was between 0.8 and 12.6%, linearity was obtained from 0.1 - 80 mg/L. The recoveries of spiked samples were between 93.7 and 104.0% (average 99.1%). The time of infusion had a considerable influence on the content of analytes found in the teas. During the brewing time, thujone and camphor show an increase up to about 5 min, after which saturation is reached. No effect was found for preparation with or without a lid on the pot used for brewing the infusion. Compared to extracts with ethanol (60% vol), which provide a maximum yield, an average of 30% thujone are recovered in the aqueous tea preparations. The average thujone and camphor contents were 4.4 mg/L and 16.7 mg/L in food tea infusions and 11.3 mg/L and 25.4 mg/L in medicinal tea infusions.

Conclusions

The developed methodology allows the efficient determination of thujone and camphor in a wide variety of sage food and medicine matrices and can be applied to conduct surveys for exposure assessment. The current results suggest that on average between 3 and 6 cups of sage tea could be daily consumed without reaching toxicological thresholds.

Metabolism of α-thujone in human hepatic preparations in vitro

This study aims to characterize the metabolism of α-thujone in human liver preparations in vitro and to identify the role of cytochrome P450 (CYP) and possibly other enzymes catalyzing α-thujone biotransformations. With a liquid chromatography-mass spectrometry (LC-MS) method developed for measuring α-thujone and four potential metabolites, it was demonstrated that human liver microsomes produced two major (7- and 4-hydroxy-thujone) and two minor (2-hydroxy-thujone and carvacrol) metabolites. Glutathione and cysteine conjugates were detected in human liver homogenates, but not quantified. No glucuronide or sulphate conjugates were detected. Major hydroxylations accounted for more than 90% of the primary microsomal metabolism of α-thujone. Screening of α-thujone metabolism with CYP recombinant enzymes indicated that CYP2A6 was principally responsible for the major 7- and 4-hydroxylation reactions, although CYP3A4 and CYP2B6 participated to a lesser extent and CYP3A4 and CYP2B6 catalyzed minor 2-hydroxylation. Based on the intrinsic efficiencies of different recombinant CYP enzymes and average abundances of these enzymes in human liver microsomes, CYP2A6 was calculated to be the most active enzyme in human liver microsomes, responsible for 70-80% of the metabolism on average. Inhibition screening indicated that α-thujone inhibited both CYP2A6 and CYP2B6, with 50% inhibitory concentration values of 15.4 and 17.5 µM, respectively.

Risk assessment of thujone in foods and medicines containing sage and wormwood--evidence for a need of regulatory changes?

Thujone is a natural substance found in plants commonly used in foods and beverages, such as wormwood and sage, as well as in herbal medicines. The current limits for thujone in food products are based on short-term animal studies from the 1960s, which provided evidence for a threshold-based mechanism, yet only allowed for the derivation of preliminary values for acceptable daily intakes (ADI) based on the no-observed effect level (NOEL). While the 2008 European Union Regulation on flavourings deregulated the food use of thujone, the European Medicines Agency introduced limits for the substance in 2009. The present study re-evaluates the available evidence using the benchmark dose (BMD) approach instead of NOEL, and for the first time includes data from a long-term chronic toxicity study of the National Toxicology Program (NTP). The NTP data provide similar results to the previous short-term studies. Using dose-response modelling, a BMD lower confidence limit for a benchmark response of 10% (BMDL10) was calculated as being 11 mg/kg bw/day for clonic seizures in male rats. Based on this, we propose an ADI of 0.11 mg/kg bw/day, which would not be reachable even for consumers of high-levels of thujone-containing foods (including absinthe). While fewer data are available concerning thujone exposure from medicines, we estimate that between 2 and 20 cups of wormwood or sage tea would be required to reach this ADI, and view that the short-term medicinal use of these herbs can also be regarded as safe. In conclusion, the evidence does not point to any need for changes in regulations but confirms the current limits as sufficiently protective for consumers.

Wormwood (Artemisia absinthium L.)--a curious plant with both neurotoxic and neuroprotective properties?

The medical use of the wormwood plant Artemisia absinthium L. dates back to at least Roman times, while during the last century this tradition was seemingly on the decline due to fears of absinthism, a syndrome allegedly caused by the wormwood-flavoured spirit absinthe and more specifically as a result of thujone, a monoterpene ketone often present in the essential oil of wormwood. If threshold concentrations are exceeded, thujone does in fact exhibit neurotoxic properties leading to dose-dependent tonic-clonic seizures in animals, likely caused by GABA type A receptor modulation. Research has shown that the concentrations of thujone present in absinthe were not sufficient to exceed these thresholds, and the marketing of wormwood-flavoured alcoholic beverages has ultimately been reinstated. The declining fears of absinthism may have led to a revival of the medical uses of wormwood, evidenced by several experimental reports, e.g. on the treatment of Crohn's disease. Most recently in this journal, neuroprotective properties of wormwood were detected in rats, and the plant was suggested to be possibly beneficial in the treatment of strokes. While these results sound promising and worthwhile for further investigation, the well-defined profile of adverse properties of wormwood demands a more cautious interpretation of these results. It remained unclear in the studies, for example, if the threshold dose for thujone (e.g. as set by the European Medicines Agency) would be exceeded during therapeutic usage. Due to the colourful history of wormwood, its application in humans should be preceded by a thorough and careful risk-benefit analysis.

Randomized comparative clinical trial of Artemisia sieberi 5% lotion and clotrimazole 1% lotion for the treatment of pityriasis versicolor

Aims:

To compare the therapeutic effects of topical Artremisia sieberi 5% lotion with topical clotrimazole 1% lotion in the treatment of pityriasis versicolor.

Materials and Methods:

100 patients with pityriasis versicolor and microscopic identification of Malassezia furfur were randomly assigned to treatment with either topical Artemisia sieberi 5% lotion (group 1) or topical clotrimazole 1% lotion (group 2) for 2 weeks. Group 1 and group 2 consisted of 51 and 49 patients respectively. The patients were evaluated both clinically and mycologically at baseline and every 2 weeks for a period of 4 weeks.

Results:

At the end of the second week, clinical cure rates were 86.3% and 65.3% for group 1 and group 2 respectively (P<0.01), but at the same time mycological cure rate was 92.2% for group 1 and 73.5% for group 2 (P<0.05). At the end of the fourth week, clinical cure rates were 86.3% and 59.2% for group 1 and group 2 respectively (P<0.01), and at the same time mycologic cure rate was 96.1% for group 1 and 65.3% for group 2 (P<0.01).

Conclusions:

The results of this study demonstrated that Artemisia sieberi 5% lotion was more effective than clotrimazole 1% lotion in the treatment of pityriasis versicolor.

Absinthe and suicidality

Absinthe is an alcoholic drink which is becoming more widely consumed after being banned for many decades. An association between absinthe use and psychiatric symptoms, ranging from impairment of concentration to marked hallucinations and seizures, has been suggested, but evidence remains unclear. Thujone, identified as a possible psychoactive ingredient, has recently been implicated in absinthe's putative neuropsychiatric effects. This report presents a case where acute suicidality emerged during absinthe consumption; possible neurobiological aetiological mechanisms and the history of absinthe use and associated adverse effects are reviewed.

Multivariate curve resolution of spectrophotometric data for the determination of artificial food colors

In the analysis of food additives, past emphasis was put on the development of chromatographic techniques to separate target components from a complex matrix. Especially in the case of artificial food colors, direct spectrophotometric measurement was seen to lack in specificity due to a high spectral overlap between different components. Multivariate curve resolution (MCR) may be used to overcome this limitation. MCR is able to (i) extract from a complex spectral feature the number of involved components, (ii) attribute the resulting spectra to chemical compounds, and (iii) quantify the individual spectral contributions with or without a priori knowledge. We have evaluated MCR for the routine analysis of yellow and blue food colors in absinthe spirits. Using calibration standards, we were able to show that MCR equally performs as compared to partial least-squares regression but with much improved chemical information contained in the predicted spectra. MCR was then applied to an authentic collective of different absinthes. As confirmed by reference analytics, the food colors were correctly assigned with a sensitivity of 0.93 and a specificity of 0.85. Besides the artificial colors, the algorithm detected a further component in some samples that could be assigned to natural coloring from chlorophyll.

Chemical composition of vintage preban absinthe with special reference to thujone, fenchone, pinocamphone, methanol, copper, and antimony concentrations

Thirteen samples of authentic absinthe dating from the preban era (i.e., prior to 1915) were analyzed for parameters that were hypothesized as contributing to the toxicity of the spirit, including naturally occurring herbal essences (thujone, pinocamphone, fenchone), methanol, higher alcohols, copper, and antimony. The total thujone content of preban absinthe was found to range between 0.5 and 48.3 mg/L, with an average concentration of 25.4 +/- 20.3 mg/L and a median concentration of 33.3 mg/L. The authors conclude that the thujone concentration of preban absinthe was generally overestimated in the past. The analysis of postban (1915-1988) and modern commercial absinthes (2003-2006) showed that the encompassed thujone ranges of all absinthes are quite similar, disproving the supposition that a fundamental difference exists between preban and modern absinthes manufactured according to historical recipes. Analyses of pinocamphone, fenchone, base spirits, copper, and antimony were inconspicuous. All things considered, nothing besides ethanol was found in the absinthes that was able to explain the syndrome "absinthism".

Plants traditionally used in age related brain disorders--a survey of ethnobotanical literature

In traditional herbal medicine, numerous plants have been used to treat age related cognitive disorders. In this review we compiled available literature from four Swiss university libraries, scientific journals and online database query's on plants and remedies used in traditional medicinal systems for such diseases. Over 150 plant species in various preparations and mixtures were found. European herbals from the 16th and 17th century alongside traditional Chinese and Indian medicinal works were the most prolific sources. The information is organised into geographic regions and when available the findings are discussed in the light of more recent scientific findings concerning their secondary metabolites and in vitro and in vivo activities relevant to dementia and Alzheimer's disease.