Ovicidal Toxicity and Morphological Changes in Housefly Eggs Induced by the Essential Oils of Star Anise and Lemongrass and Their Main Constituents.

This study attempted to evaluate the ovicidal activity of single-component formulations and combination formulations of lemongrass and star anise essential oils (EOs) and their main constituents against housefly eggs. The efficacies of the combinations were compared with those of single-component formulations and α-cypermethrin. Safety bioassays of all treatments and α-cypermethrin on non-target predators-guppy and molly-were conducted. Two combinations: 1% lemongrass EO + 1% trans-anethole and 1% star anise EO + 1% geranial, exhibited a strong ovicidal activity with an inhibition rate of 94.4 to 96.2%. They were 1.1 times as effective as α-cypermethrin. The two combinations also showed high synergistic activity compared to single-component formulations, with a high synergistic index and a high increased inhibition value of 37.4 to 57.7%. All EO treatments were benign for all non-target aquatic species with a high 50% lethal time (LT50) and safety index. In contrast, α-cypermethrin was highly toxic to them with a low LT50. The morphological abnormalities observed in housefly eggs at death were those such as the shrivelling of the eggs, aberrations and damage to the eggshells, hatching lines, aeropyles, plastron, and micropyle. The potential of these two combinations as a cypermethrin replacement is compelling.

Combinations of Lemongrass and Star Anise Essential Oils and Their Main Constituent: Synergistic Housefly Repellency and Safety against Non-Target Organisms.

The present study evaluated the housefly repellency of single-component formulations and combinations of lemongrass and star anise essential oils (EOs) and their main constituents. The efficacies of the combinations were compared against those of single-component formulations and DEET. Safety bioassays of all formulations and DEET on non-target species-guppy, molly, dwarf honeybee, and stingless bee-were conducted. GC-MS analysis showed that the main constituent of lemongrass EO was geranial (46.83%) and that of star anise EO was trans-anethole (92.88%). All combinations were highly synergistic compared to single-component formulations, with an increased repellent value (IR) of 34.6 to 51.2%. The greatest synergistic effect was achieved by 1.0% lemongrass EO + 1.0% trans-anethole combination, with an IR of 51.2%. The strongest, 100% repellent rate at 6 h was achieved by 1.0% geranial + 1.0% trans-anethole. They were twice as effective as DEET and caused obvious damage to housefly antennae under microscopic observation. All single-component formulations and combinations were benign to the four tested non-target species. In contrast, DEET was highly toxic to them. The synergistic repellency and biosafety of these two combinations are compellingly strong support for developing them into an effective green repellent.

Safety and efficacy of a feed additive consisting of an essential oil derived from the aerial parts of Cymbopogon flexuosus (Nees ex Steud.) Will. Watson (lemongrass oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of lemongrass oil obtained from the aerial parts of Cymbopogon flexuosus (Nees ex Steud.) Will. Watson when used as a sensory additive for all animal species. The FEEDAP Panel concluded that lemongrass oil is safe up to the maximum proposed use levels in complete feed of 125 mg/kg for salmonids; 100 mg/kg for sows and horses; 75 mg/kg for veal calves (milk replacer), cattle for fattening, dairy cows, sheep and goats; and 50 mg/kg for dogs and ornamental fish. For the other species, the calculated safe concentrations in complete feed were 41 mg/kg for chickens for fattening, 61 mg/kg for laying hens, 55 mg/kg for turkeys for fattening, 74 mg/kg for piglets, 88 mg/kg for pigs for fattening, 65 mg/kg for rabbits and 33 mg/kg for cats. These conclusions were extrapolated to other physiologically related species. For any other species, the additive is safe at 33 mg/kg complete feed. The use of lemongrass oil in water for drinking for poultry, pigs, calves and rabbit is safe provided that the total daily intake does not exceed the daily amount considered safe when consumed via feed. No concerns for consumers and the environment were identified following the use of the additive up to the highest safe use level in feed. The essential oil under assessment should be considered as an irritant to skin and eyes and as a dermal and respiratory sensitiser. Since the aerial parts of C. flexuosus and its preparations were 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.

After chemo-metamorphosis: p-menthane monoterpenoids characterize the oil gland secretion of adults of the oribatid mite, Nothrus palustris.

The oil gland secretion of the oribatid mite Nothrus palustris is known to show the phenomenon of juvenile-adult polymorphism, i.e., juvenile instars produce secretions predominated by geranial, whereas adults secrete dehydrocineole along with a number of chemically unidentified compounds. We here re-analyzed the secretions of adult N. palustris by GC-MS and NMR spectroscopy, eventually identifying the unknown compounds as p-menthane monoterpenoids. The major components were two isomeric 6-isopropenyl-3-methyl-cyclohex-3-en-1-yl formates (= p-1,8-menthadien-5-yl formates), which accounted for about 75% of the secretion. These were accompanied by five additional, only partly identified p-menthanes (or p-methane-derivatives), all of which represented minor or trace components. In addition, adult secretions contained two C21-hydrocarbons, 1,12-heneicosadiene (major) and a heneicosatriene (minor). Menthane monoterpenoids represent a novel sub-class of terpene compounds in the oil gland secretions of Oribatida. In case of N. palustris, we assume that both geranial and p-menthane monoterpenoids arise via the mevalonate pathway which obviously shows a split at the level of geranyl pyrophosphate, leading to geranial in juveniles and to p-menthanes in adults. The significance of methane occurrence in oil glands as well as the taxonomic distribution of juvenile-adult polymorphism in oribatid oil gland secretions is discussed. The latter phenomenon-i.e., "chemo-metamorphosis" of secretions-is not known from early- and middle-derivative Oribatida nor from Astigmata, but appears to be more common in some derivative desmonomatan and brachypyline oribatid groups.

Aroma profiling of Shine Muscat grape provides detailed insights into the regulatory effect of gibberellic acid and N-(2-chloro-4-pyridinyl)-N-phenylurea applications on aroma quality.

As plant growth regulators, gibberellic acid (GA3) and CPPU [forchlorfenuron, N-(2-chloro-4-pyridinyl)-N-phenylurea] are widely used in the production of table grapes. However, how these compounds regulate the aroma quality remains unclear. By measuring free and bound aroma compounds in Shine Muscat grapes from eight groups during whole growth period, GA3 and CPPU were both found to significantly promote the synthesis of acyclic monoterpenes and (E)-2-hexenal, and double applications were found to further increase the aroma compound contents. On the other hand, GA3 and CPPU obviously promoted the expansion of berries, and the effect of promoting the synthesis of aroma compounds was largely diminished. In conclusion, free compound concentrations in berry were almost unaffected by GA3 and CPPU. From the perspective of aroma compounds, a highly concerted interplay was observed for terpenes, and bound compounds exhibited higher correlations than those of free compounds. In addition, 17 compounds could be used as markers that indicated the developmental timing of berries.

Influence of peeling on volatile and non-volatile compounds responsible for aroma, sensory, and nutrition in ginger (Zingiber officinale).

Industrial use of ginger after peeling results in large amounts of agro-waste. To provide a basic reference for the sustainable processing of ginger products as a spice, we investigated the differences between unpeeled ginger, peeled ginger, and corresponding ginger peel, in terms of aroma, sensory profiles, and nutrition relevant physicochemical properties. The results showed that the total concentrations of identified odor-active compounds in unpeeled ginger, peeled ginger, and ginger peel were 876.56, 672.73, and 105.39 mg/kg, respectively. Unpeeled ginger exhibited more intense citrus-like and fresh impressions compared to peeled ginger, revealed by descriptive sensory analyses. This is relevant to the high odor activity values of odorants such as ß-myrcene (pungent, citrus-like), geranial (citrus-like), citronellal (citrus-like, sourish), and linalool (floral, fresh). In parallel, unpeeled ginger contained higher total polyphenol (84.49 mg/100 g) and total sugar content (33.4 g/kg) in comparison with peeled ginger (76.53 mg/100 g and 28.6 g/kg).

Review of anticancer activity of monoterpenoids: Geraniol, nerol, geranial and neral.

In recent years head-to-tail monoterpene geraniol has been widely explored as a potential anticancer agent. Natural analogs like alcohol nerol, aldehydes geranial, and neral have been investigated. We explored the synergism of these terpenes with clinically and non-clinically used compounds as potential candidates for treating different types of cancer. Promising activity for these compounds has also inspired new analog syntheses. The anticancer potential of these compounds is described in this review.

Backhousia citriodora F. Muell. (Lemon Myrtle), an Unrivalled Source of Citral.

Lemon oils are amongst the highest volume and most frequently traded of the flavor and fragrance essential oils. Citronellal and citral are considered the key components responsible for the lemon note with citral (neral + geranial) preferred. Of the myriad of sources of citral, the Australian myrtaceous tree, Lemon Myrtle, Backhousia citriodora F. Muell. (Myrtaceae), is considered superior. This review examines the history, the natural occurrence, the cultivation, the taxonomy, the chemistry, the biological activity, the toxicology, the standardisation and the commercialisation of Backhousia citriodora especially in relation to its essential oil.

Antifungal Activities of cis-trans Citral Isomers against Trichophyton rubrum with ERG6 as a Potential Target.

Trichophyton rubrum causes ringworm worldwide. Citral (CIT), extracted from Pectis plants, is a monoterpene and naturally composed of geometric isomers neral (cis-citral) and geranial (trans-citral). CIT has promising antifungal activities and ergosterol biosynthesis inhibition effects against several pathogenic fungi. However, no study has focused on neral and geranial against T. rubrum, which hinders the clinical application of CIT. This study aimed to compare antifungal activities of neral and geranial and preliminarily elucidate their ergosterol biosynthesis inhibition mechanism against T. rubrum. Herein, the disc diffusion assays, cellular leakage measurement, flow cytometry, SEM/TEM observation, sterol quantification, and sterol pattern change analyses were employed. The results showed geranial exhibited larger inhibition zones (p < 0.01 or 0.05), higher cellular leakage rates (p < 0.01), increased conidia with damaged membranes (p < 0.01) within 24 h, more distinct shriveled mycelium in SEM, prominent cellular material leakage, membrane damage, and morphological changes in TEM. Furthermore, geranial possessed more promising ergosterol biosynthesis inhibition effects than neral, and both induced the synthesis of 7-Dehydrodesmosterol and Cholesta-5,7,22,24-tetraen-3ß-ol, which represented marker sterols when ERG6 was affected. These results suggest geranial is more potent than neral against T. rubrum, and both inhibit ergosterol biosynthesis by affecting ERG6.

Safety and efficacy of a feed additive consisting of an essential oil from the fruits of Litsea cubeba (Lour.) Pers. (litsea berry oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from the fruits of Litsea cubeba (Lour.) Pers. (litsea berry oil), when used as a sensory additive (flavouring) in feed and water for drinking for all animal species. The FEEDAP Panel concluded that litsea berry oil is safe up to the maximum proposed use level of 125 mg/kg complete feed for ornamental fish. For the other species, the calculated safe concentration in complete feed are 11 mg/kg for chicken for fattening, 16 mg/kg for laying hen, 14 mg/kg for turkey for fattening, 19 mg/kg for piglet, 23 mg/kg for pig for fattening, 28 mg/kg for lactating sow, 48 mg/kg for veal calf (milk replacer), 43 mg/kg for cattle for fattening, sheep, goat and horse, 28 mg/kg for dairy cow, 17 mg/kg for rabbit, 47 mg/kg for salmon, 50 mg/kg for dog and 8.5 mg/kg for cat. The FEEDAP Panel also concluded that the use of litsea berry oil at the maximum proposed use level in water for drinking of 1 mg/kg is safe for all animal species. Simultaneous use in feed and water for drinking may lead to the maximum safe dose being exceeded. No concerns for consumer safety were identified following the use of the additive up to the highest safe use level in feed for the target animals. The essential oil under assessment should be considered as irritant to skin and eyes, and as a skin and respiratory sensitiser. The use of the additive in animal feed under the proposed conditions was not expected to pose a risk for the environment. Litsea berry oil is recognised to flavour food. Since its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Insecticidal and Attractant Activities of Magnolia citrata Leaf Essential Oil against Two Major Pests from Diptera: Aedes aegypti (Culicidae) and Ceratitis capitata (Tephritidae).

In this study, Magnolia citrata Noot and Chalermglin (Magnoliaceae) essential oil (MCEO) was evaluated for insecticidal activity against the yellow fever mosquito Aedes aegypti and attractant activity for the Mediterranean fruit fly Ceratitis capitata. The leaves of Magnolia citrata (Gioi chanh) were collected from northwestern Vietnam, and the water-distilled MCEO was analyzed by gas-chromatography and mass spectrometry (GC-MS). The major constituents of MCEO were identified as linalool 19%, geranial 16%, citronellal 14%, neral 14%, and sabinene 12%. MCEO showed 100% mortality at 1 µg/µL against 1st instar larvae of Ae. aegypti (Orlando strain, ORL), and the oil exhibited 54% (ORL) and 68% (Puerto Rico strain) mortality at 5 µg/mosquito against Ae. aegypti adult females. Initial screens showed that MCEO had weak insecticidal activity compared to the positive control permethrin. In bioassays with sterile male C. capitata, MCEO exhibited moderately strong attraction, comparable to that observed with a positive control, Tetradenia riparia essential oil (TREO). Herein, the insecticidal and attractant activities of MCEO are reported for the first time.

Quantitation of Key Aroma Compounds in Fresh, Raw Ginger (Zingiber officinale Roscoe) from China and Roasted Ginger by Stable Isotope Dilution Assays and Aroma Profiling by Recombination Experiments.

Twenty key odorants recently identified in raw and roasted ginger were quantitated by means of stable isotope dilution assays, of which six assays were newly developed. Odor activity values (OAV; ratio of concentration to odor threshold) revealed 1,8-cineol (eucalyptus-like) with by far the highest value of 65 000 followed by myrcene (geranium-like), for which an OAV of 19 000 was calculated. In addition, (R)-citronellal, geranial, (R)-linalool, (E)-isoeugenol, and (E)-2-octenal contributed with high OAVs to the overall aroma profile of the fresh, raw ginger. An aroma recombinate prepared with 20 reference compounds in the same concentrations as determined in the ginger sample successfully matched the overall aroma profile. In the roasted ginger, 1,8-cineol and myrcene remained the most odor-active compounds, however, the increase in some odorants, for example, in geraniol and (Z)-2-decenal, in combination with the newly formed caramel-like smelling 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like) and 3-(methylthio)propanal (potato-like) most likely caused the differences in the aroma profile initiated by the thermal treatment. A biomimetic aroma recombinate based on 21 aroma compounds was able to successfully simulate the aroma profile of the roasted ginger.

Chemical composition and selective BuChE inhibitory activity of the essential oils from aromatic plants used to prepare the traditional Ecuadorian beverage horchata lojana.

ETHNOBOTANICAL AND ETHNOMEDICINAL RELEVANCE: In southern Ecuador, horchata lojana is a popular aromatic and refreshing beverage that is prepared from an aqueous infusion of different mixtures of local medicinal and aromatic plants. The drink is considered a traditional anti-inflammatory agent and brain tonic; due these properties, it has been drunk since Colonial Times. Several pharmacological studies have evaluated the effects of horchata aqueous infusion. However, the aromatic profile and the contribution of the volatile components to the biological activity of the drink have not been investigated so far. For these reasons, we have determined the chemical composition of the essential oils (EOs) distilled from five mixtures of aromatic plants commonly used for the preparation of this traditional drink. Moreover, to support the curative properties of the aromatic plants, the anticholinesterase activity of the EOs was examined. MATERIAL AND METHODS: Different bunches of fresh mixed medicinal and aromatic plants, called tongos, are sold at local markets in the province of Loja for the preparation of different types of horchata. In this research we have purchased plant bunches sold at five popular markets of Loja province. Subsequently, aromatic plants in each bunch were separated from medicinal plants and were then hydrodistilled to give the corresponding EOs. Subsequently, the chemical composition of each EO was determined by GC-MS/GC-FID techniques, whereas the cholinesterase inhibitory activity in vitro was determined against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. AIMS OF THE STUDY: i) to contribute to the chemical and pharmacological study of the aroma components of the traditional Ecuadorian drink horchata lojana; ii) to identify botanically the mixtures of aromatic plants used to make the drink; iii) to establish, on the basis of the chemical composition of the EOs, the compounds mainly responsible for the characteristic beverage flavor; iv) to establish the possible existence of an aromatic pattern characteristic of each horchata preparation; v) to test the anticholinesterase activity of the EOs against AChE and BuChE in order to support the traditional consume of the drink as an effective brain tonic. RESULTS: A total of 23 botanical families and 32 species of plants used for the preparation of five different variants of the traditional horchata lojana beverage, have been identified. Fourteen aromatic species were determined to be responsible for the characteristic flavor of the drink. All the analyzed EOs belong to the monoterpene type. A total of 88 compounds have been identified in the different EOs, twenty-four of which are common components of the oils. CONCLUSIONS: According to the main components of the EOs distilled from the five groups of horchata lojana plants, four aromatic profiles have been defined: (i) neral + geranial + carvone, (ii) neral + geranial + myrcene; (iii) geranial + methyl eugenol + isomenthone + neral + citronellol; (iv) (E)-anethole + geranial + pulegone. Moreover, according to the literature, several aromatic plants and individual EOs components exhibit a wide range of biological activities. This finding as well as the significant BuChE inhibitory activity exhibited in vitro by the EOs give scientific support to the use of identified aromatic plants in the traditional preparation of horchata, that is considered a natural analgesic and anti-inflammatory remedy, and an effective brain tonic.

Reactive oxygen species mediated-antifungal activity of cinnamon bark (Cinnamomum verum) and lemongrass (Cymbopogon citratus) essential oils and their constituents against two phytopathogenic fungi.

To find new and safe type of control agents against phytopathogenic fungi, the fumigant antifungal activity of 10 plant essential oils and constituents identified in cinnamon bark (Cinnamomum verum) and lemongrass (Cymbopogon citratus) essential oils was investigated against two phytopathogenic fungi, Raffaelea quercus-mongolicae and Rhizoctonia solani. Among plant essential oils, cinnamon bark and lemongrass essential oils showed 100% inhibition of R. quercus-mongolicae and R. solani at 5 mg/paper disc, respectively. Among test constituents, salicylaldehyde, eugenol, and hydrocinnamaldehyde showed 100% inhibition of growth of R. quercus-mongolicae at 2.5 mg/paper disc. Neral, geraniol, geranial, trans-cinnamaldehyde, methyl cinnamate, isoeugenol, and methyl eugenol exhibited >80% inhibition of growth of R. quercus-mongolicae at 2.5 mg/paper disc. Neral, geranial, trans-cinnamaldehyde, hydrocinnamaldehyde, and salicylaldehyde showed 100% inhibition of growth of R. solani at 2.5 mg/paper disc. A fumigant antifungal bioassay of artificial blends of the constituents identified in cinnamon bark and lemongrass essential oils indicated that trans-cinnamaldehyde and geranial were major contributors to the fumigant antifungal activity of the artificial blend. Confocal laser scanning microscopy images of fungi treated with cinnamon bark and lemongrass essential oils, trans-cinnamaldehyde, neral, and geranial revealed the reactive oxygen species (ROS) generation and cell membrane disruption.

Targets and pathways involved in the antitumor activity of citral and its stereo-isomers.

This review provides a comprehensive analysis of the anticancer potential of the natural product citral (CIT) found in many plants and essential oils, and extensively used in the food and cosmetic industry. CIT is composed of two stereoisomers, the trans-isomer geranial being a more potent anticancer compound than the cis-isomer neral. CIT inhibits cancer cell proliferation and induces cancer cell apoptosis. Its pluri-factorial mechanism of anticancer activity is essentially based on three pillars: (i) a drug-induced accumulation of reactive oxygen species in cancer cells leading to an oxidative burst and DNA damages, (ii) a colchicine-like inhibition of tubulin polymerization and promotion of microtubule depolymerization, associated with an inhibition of the microtubule affinity-regulating kinase MARK4, and (iii) a potent inhibition of the aldehyde dehydrogenase isoform ALDH1A3 which is associated with cancer stem cell proliferation and chemoresistance. This unique combination of targets and pathways confers a significant anticancer potential. However, the intrinsic potency of CIT is limited, mainly because the drug is not very stable and has a low bioavailability and it does not present a high selectivity for cancer cells versus non-tumor cells. Stable formulations of CIT, using cyclodextrins, biodegradable polymers, or various nano-structured particles have been designed to enhance the bioavailability, to increase the effective doses window and to promote the anticancer activity. The lack of tumor cell selectivity is more problematic and limits the use of the drug in cancer therapy. Nevertheless, CIT offers interesting perspectives to design more potent analogues and drug combinations with a reinforced antitumor potential.

Contact allergy to citral and its constituents geranial and neral, coupled with reactions to the prehapten and prohapten geraniol.

BACKGROUND: Citral is commonly used as a fragrance and flavor material and consists of the aldehydes geranial and neral. Citral is included in fragrance mix (FM) II. Geranial and neral have also been identified in autoxidation of geraniol, a fragrance compound present in FM I. OBJECTIVES: To study contact allergy to citral, geranial, and neral, and concomitant reactivity to oxidized geraniol and fragrance markers of the baseline series. METHODS: A total of 1476 dermatitis patients with suspected allergic contact dermatitis were patch tested using geranial, neral, and citral, all 3.5% petrolatum (pet.) as well as geraniol 6.0% and oxidized geraniol 11% pet. in addition to the Swedish baseline series. RESULTS: Frequencies of positive reactions to citral, geranial, and neral were 2.9%, 3.4% and 1.9%, respectively. Together, citral and geranial gave 4.2% positive patch test reactions in consecutive dermatitis patients. In patients with positive reactions to citral or its components, 25% to 34% reacted to FM II and 61% reacted to oxidized geraniol. CONCLUSIONS: Patch testing with citral, its components, or oxidized geraniol detects contact allergic reactions not detected using the baseline series. Patch testing with pure geraniol was shown to be of little value. Geranial and neral, although closely chemically related, are concluded to be separate haptens.

Essential oils of basil chemotypes: Major compounds, binary mixtures, and antioxidant activity.

The antioxidant potential of the essential oils (EO) of 24 basil genotypes was assessed by 4 distinct in vitro evaluation methods. Different combinations of the major compounds found in the EO were also tested to identify those combinations responsible for the antioxidant activity of the volatile oils and verify the occurrence of synergism or antagonism between them. Results indicate that 9 EO exhibited promising antioxidant potential, with at least 52.68% of inhibition of the linoleic acid peroxidation at 10 µL/mL and 76.34% of inhibition of the DPPH radical at 1 µL/mL. The major compound eugenol had the highest antioxidant activity. The antioxidant activity of these EO cannot be explained solely by the presence of the major compounds. Despite the influence of eugenol, the antioxidant activity is also related to the synergism between other minor compounds found in the EO. This fact confers a potent antioxidant activity to some basil EO.

Composition of essential oil of lemon thyme (Thymus × citriodorus) at different hydrodistillation times.

Distillation time can both to optimise the production and to engineer the composition of essential oil in essential oil bearing plants. Purpose of this study was to evaluate the effect of duration of hydrodistillation on composition of essential oil of Thymus × citriodorus, the natural source of commercially important geraniol and citral, a component with valuable biological properties. Essential oils were isolated by hydrodistillation at different distillation times and analysed by GC/MS analytical methods. Increase in percentage of essential oil during all hydrodistillation time gradient was uneven. Elongation of hydrodistillation time decreased percentages of monoterpenes but increased percentages of sesquiterpenes in essential oil. Results showed that the hydrodistillation of essential oil from lemon thyme longer than 60 min is useless.

Chemical composition and antimicrobial activity of Myrcianthes fragrans essential oil, a natural aromatizer of the traditional Ecuadorian beverage colada morada.

ETHNOBOTANICAL AND ETHNOMEDICINAL RELEVANCE: The importance given in Ecuador to the rescue of traditional knowledge and nutritional value of ancestral foods and drinks, has stimulated our investigation of the chemical composition and some biological activities of M. fragrans ('arrayán') essential oil, a natural aromatic additive used in the preparation of the traditional fruit-juice 'colada morada', which is typically drunk in the Day of the Dead or All Soul´s Day. MATERIAL AND METHODS: Different essential oils of Myrcianthes fragrans (Sw.) McVaught were obtained by hydrodistillation of the aerial parts of the plant collected in Cerro Villonaco (Loja-Ecuador) at three different phenological growth stages, i.e., during foliation (Fo), flowering (Fl) and fruiting (Fr) stages. The chemical compositions of the essential oils were determined by GC/MS and GC/FID techniques. The antimicrobial activities were determined by the broth microdilution method and reported as minimal inhibitory concentration (MIC, ug/mL). AIMS OF THE STUDY: i) to investigate the traditional uses of arrayán (M. fragrans) in the South region of Ecuador; ii) to identify the main components of the essential oils isolated at different phenological stages; iiì) to test the antimicrobial activity of the essential oils against bacteria and yeasts causing human ailments and a yeast causing food spoilage. RESULTS: 37, 46 and 38 compounds, representing 96.5%, 96.2%, and 95.6% of the three essential oils (Fo, Fl and Fr), respectively, have been identified. Oxygenated monoterpenes (OM) were the major components with percentages of 63.1 (Fo), 49.4 (Fl), and 61.9% (Fr), respectively. The main constituents of the essential oils were the monoterpene aldehydes geranial (1) and neral (2), the content of which varied, depending on the phenological development stage of the plant, spanning from 31.1% and 23.6% (Fo), to 23.6% and 17.8% (Fl), and 29.7% and 24.3% (Fr), respectively. In vitro antimicrobial tests showed that the essential oils from M. fragrans exhibited good activity against the Gram-negative bacteria, K. pneumoniae, and against the yeasts, C. albicans and S. cerevisiae. CONCLUSIONS: The oil is characterized by a high concentration of the monoterpene aldehydes geranial and neral (citral), that make the aroma of colada morada prepared in southern Ecuador quite different from the beverage made in other regions of the country, where other types of myrtles (Myrtaceae spp.) are used. Moreover, the oil may become a new rich source of the important industrial chemical citral. The pleasant aromatic properties and the good in vitro antimicrobial activity of arrayán oil suggest a plausible scientific explanation for the traditional uses of the plant not only as a natural aromatizer of a traditional beverage but also as a natural anti-infective and anti-yeast agent.

Volatile Compounds from the Different Organs of Houttuynia cordata and Litsea cubeba (L. citriodora).

The volatile compounds obtained from the different organs of Houttuynia cordata (Saururaceae) and Litsea cubeba (Lauraceae) were analyzed by Gas Chromatography/Mass Spectrometry (GC/MS), Headspace Solid Phase Micro Extraction-Gas Chromatography/Mass Spectrometry (HS-SPME-GC/MS), and GC/olfactometry (GC/O). The major component of all parts of H. cordata is assigned as 4-tridecanone. Each organ produces myrcene as the major monoterpenoid. The major monoterpene in the rhizomes and roots was ß-pinene instead of myrcene. 1-Decanal which was responsible for the unpleasant odor of this plant, was the predominant polyketide in both leaves and stems. The presence of 1-decanal was very poor in flowers, stem collected in summer, rhizomes, and roots. GC/MS analyses were very simple in case of the crude extracts of flowers. The content of sesquiterpenoids was extremely poor. (8Z)-Heptadecene, geranial, and neral were detected as the major components in Litsea cubeba. Odor-contributing components by GC/O analysis of the ether extract of the fresh flowers of L. cubeba were neral and geranial which played an important role in sweet-lemon fragrance of the flowers. The role of a high content of (8Z)-heptadecene was still unknown but it might play a significant role in the dispersion of the volatile monoterpene hydrocarbons and aldehydes. The flower volatiles of the Japanese L. cubeba were chemically quite different from those of the Chinese same species.