Anxiolytic-like activity of Aloysia virgatavar. platyphylla leaves extract in mice / Actividad ansiolítica del extracto de hojas de Aloysia virgatavar. platyphylla en ratones

Background: Medicinal plants are part of traditional medicine and should be considered a therapeutic alternative for mental diseases. Several plants belonging to the Verbenaceae family have proved useful in treating general anxiety disorders, the most prevalent psychiatric disorders. Objective: This research aimed to verify the extract's safety, the effect on general behavior, and the effect on sleeping time, as well as to evaluate the anxiolytic-like effect of the methanol extract of Aloysia virgata var. platyphylla (Avp), in mice. Methodology: The toxicity test was done according to the OECD guide (mice groups n=5), and general behavior was observed during the assay. Sleeping time was assessed using the pentobarbital-induced hypnosis method (n=8). Male Swiss albino mice (n=6) were treated with 50 to 400 mg/kg of Avp extract and diazepam as a control. The anxiolytic-like effect was tested through the hole board and elevated plus-maze test. Results: The Avp extract has no side effects in tested doses, and no central nervous system depressant activity was noted. A. virgatavar. platyphyllaincreased exploration (number and time) in the hole board. In the elevated plus-maze, increased number and time into open arms were evidenced compared to the control group. Conclusion: With all these results, we concluded that the Avp extract is safe and has a potential anxiolytic-like activity in the animal model used

Antecedentes: Las plantas medicinales forman parte de la medicina tradicional y deben ser consideradas una alternativa terapéutica para las enfermedades mentales. Varias plantas pertenecientes a la familia Verbenaceae han demostrado su utilidad en el tratamiento de los trastornos de ansiedad, uno de los trastornos psiquiátricos más prevalentes. Objetivo: Esta investigación tuvo como objetivo verificar la seguridad del extracto, el efecto sobre el comportamiento general y el efecto sobre el tiempo de sueño, así como evaluar el efecto tipo ansiolítico del extracto metanólico de Aloysia virgata var. platyphylla(Avp), en ratones. Metodología: La prueba de toxicidad se realizó de acuerdo con la guía de la OCDE (grupos de ratones n=5), y se observó el comportamiento general durante el ensayo. El tiempo de sueño se evaluó mediante el método de hipnosis inducida por pentobarbital (n=8). Se trataron ratones albinos suizos macho (n=6) con 50 a 400 mg/kg de extracto de Avp y diazepam como control. El efecto ansiolítico se probó a través de la placa perforada y prueba del laberinto en cruz elevado. Resultados: El extracto de Avp no tiene efectos secundarios en las dosis probadas y no se observó actividad depresora del sistema nervioso central. A. virgata var. platyphylla aumentó la exploración (número y tiempo) en el tablero de agujeros. En el laberinto en cruz elevado, se evidenció un mayor número y tiempo en los brazos abiertos en comparación con el grupo de control. Conclusión: Con todos estos resultados, concluimos que el extracto de Avp es seguro y tiene una potencial actividad ansiolítica en el modelo animal utilizado

Caracterización in situ de poblaciones de Aloysia gratissima var. gratissima recolectadas del noreste de la provincia de San Luis, Argentina / In situ characterization of populations of Aloysia gratissima var. gratissima collected from the northeast of the province of San Luis, Argentina

Abstract: The aerial part of Aloysia gratissima (Gil lies & Hook. ex Hook.) Tronc., "Usillo", is used as aromatic and medicinal. It is a shrub of up to 3 meters, distributed in North America, from the south of the USA to the north of Mexico, and in South America up to the 37th parallel. As in other native sp ecies, the demand is covered by harvesting in wild populations, which brings about the deterioration of the resource and lack of homogeneity of the harvested product. The variability was characterized in nine populations of A. gratissima var. gratissima fr om the northeast of San Luis, Argentina, based on morphological and phytochemical characters. It was found that the species in the region presents considerable heterogeneity. Diversity was detected in the chemical characteristics of the essential oils anal yzed and the prevalence of mono and sesquiterpenes was related to the olfactory identities identified. The main components were the sesquiterpene spatulenol and the monoterpene 1,8 cineole

Resumen: La parte aérea de Aloysia gratissima (Gillies & Hook. ex Hook.) Tronc., "usillo", es utilizada como aromática y medicinal. Es un arbusto de hasta 3 metros, distribuido en Norteamerica, desde e l sur de EEUU hasta el norte de México, y en Sudamerica hasta el paralelo 37°. Al igual que en otras especies nativas, la demanda es cubierta por recolección en poblaciones silvestres, lo cual trae aparejado el deterioro del recurso y falta de homogeneidad del producto cosechado. Se caracterizó la variabilidad en nueve poblaciones de A. gratissima var. gratissima del noreste de San Luis, Argentina, en base a caracteres morfológicos y fitoquímicos. Se encontró que la especie en la región presenta una conside rable heterogeneidad. Se detectó diversidad en las características químicas de los aceites esenciales analizados y se relacionó la prevalencia de mono y sesquiterpenos con las identidades olfativas identificadas. Los componentes mayoritarios fueron el sesq uiterpeno espatulenol y el monoterpeno 1,8 cineol.

Actividad gastroprotectora, tamizaje fitoquímico y actividad atrapadora de radicales libres de Aloysia Gratissima (Verbenaceae) / Phytochemical screning, gastroprotective activity and free radical scavenging activity of Aloysia gratissima (Verbenaceae)

Se evaluó la actividad gastroprotectora de la infusión proveniente de las hojas de Aloysia gratissima (Verbenaceae), especie nativa de interés medicinal que se desarrolla en el sudoeste bonaerense, utilizando un modelo de inducción de úlceras gástricas con etanol en ratones. Se realizó un tamizaje fitoquímico para detectar la presencia de compuestos que podrían ser responsables de la actividad gastroprotectora de la planta. Se determinó el contenido de fenoles totales y la capacidad atrapadora de radicales libres mediante el método del Folin-Ciocalteu y del 2,2'-difenil-1-picrilhidrazilo (DPPH), respectivamente. Los ensayos demostraron que la infusión de la planta, administrada por vía oral en dosis de 100, 500 y 1000 mg/kg, ejerció una gastroprotección significativa frente a la inducción de úlceras. Se detectó una actividad atrapadora de radicales libres de 47,5%, similar a la sustancia de referencia (BHT). El estudio fitoquímico detectó la presencia de flavonoides y otros polifenoles, sustancias con reconocida capacidad antioxidante. Estos metabolitos ejercen efectos protectores en diferentes modelos experimentales de inducción de úlceras mediante mecanismos que pueden involucrar la neutralización de radicales libres, lo que podría explicar la actividad gastroprotectora de la planta. Estos hallazgos requieren estudios adicionales de A. gratissima como una posible terapia frente a la úlcera gástrica. (AU)

The gastroprotective activity of the infusion from the leaves of Aloysia gratissima (Verbenaceae), a native species of medicinal interest growing in South West Buenos Aires, was evaluated in an ethanol-induced gastric ulcer model in mice. Phytochemical screening was carried out in order to determine the presence of compounds that could be responsible for the pharmacological effects of the plant. Total phenolic content and the free radical scavenging activity of the plant were determined using the Folin-Ciocalteu and the 2,2'-diphenyl1-picrylhydrazyl (DPPH) method, respectively. Assays demonstrated that the infusion, orally administered at 100, 500, and 1000 mg/kg doses, exerted a significant gastroprotection effect against ulcer induction (P<0,05). A free radical scavenging activity of 47.5% -similar to the reference substance (BHT)- was detected. Phytochemical screening revealed the presence of antioxidant compounds such as flavonoids and other phenolic compounds. These compounds exert protective effects in different experimental models of ulcer induction that could involve free radical neutralization, which could explain the gastroprotective activity of the plant. These promising results support additional studies of A. gratissima as a potential therapy against gastric ulcer. (AU)

Fungicidal potential of essential oils in control of Fusarium spp. and Sclerotinia sclerotiorum / Potencial fungicida de óleos essenciais no controle de Fusarium spp. e Sclerotinia sclerotiorum

The use of highly toxic pesticides to control soil pathogens, such as Fusarium spp. and Sclerotinia sclerotiorum has generated concern, due to the irreversible impacts caused on the environment, in addition to selecting resistant isolates. In this way, essential oils appear as an efficient alternative in control of diseases. Facing the problem of soil pathogens control and high antimicrobial fungicide that essential oils present, this work aimed to evaluate the in vitro fungicidal potential of essential oils in control of Fusarium spp. and S. sclerotiorum. A completely randomized design, factorial scheme 2×4×8 was used, with two isolates (Fusarium spp. and S. sclerotiorum), four essential oils (Aloysia citriodora, Cymbopogon winterianus, Lippia alba and Ocimum americanum), eight essential oil concentrations (0.0; 0.2; 0.4; 0.6; 0.8; 1.0; 1.2 and 1.4 ?L·mL-1), and ten replicates. The essential oils inhibited mycelial growth of the fungi in different concentrations, being their potential justified by the presence of antifungal chemical compounds. Essential oils of A. citriodora, C. winterianus, L. alba and O. americanum present high fungicidal potential, being viable alternatives for formulation of commercial products, boosting the pesticides industry.(AU)

O uso de pesticidas com alta toxicidade para controlar patógenos do solo, como Fusarium spp. e Sclerotinia sclerotiorum, tem gerado preocupação, devido aos impactos irreversíveis causados no meio ambiente, além de selecionar isolados resistentes. Dessa forma, os óleos essenciais surgem como uma alternativa eficiente no controle de doenças. Diante da problemática de controle de patógenos do solo e alto potencial antimicrobiano que os óleos essenciais possuem, este trabalho teve como objetivo avaliar o potencial fungicida de óleos essenciais no controle de Fusarium spp. e S. sclerotiorum, in vitro. Utilizou-se um delineamento inteiramente randomizado, esquema fatorial 2×4×8, com dois isolados (Fusarium spp. e S. sclerotiorum), quatro óleos essenciais (Aloysia citriodora, Cymbopogon winterianus, Lippia alba e Ocimum americanum) e oito concentrações de óleo essencial (0,0; 0,2; 0,4; 0,6; 0,8; 1,0; 1,2 e 1,4 ?L·mL-1), com dez repetições. Os óleos essenciais inibiram o crescimento micelial dos fungos em diferentes concentrações, sendo seu potencial justificado pela presença de compostos químicos antifúngicos. Os óleos essenciais de A. citriodora, C. winterianus, L. alba e O. americanum apresentam alto potencial fungicida, sendo alternativas viáveis para formulação de produtos comerciais, impulsionando a indústria de agrotóxicos.(AU)

In vitro propagation of lemon verbena: a plant native of South America

In vitropropagation increases the supply and commercialisation of products of interest. For this, optimising the growing conditions and the composition of the culture medium is crucial to benefit the full development of the plants. Thus, the objective was to evaluate the in vitropropagation of Aloysia triphyllaon different culture media, with varying agar and sucrose concentrations. The experiment was conducted as a completely randomised design, 3×3×3 factorial scheme, with three culture media (MS, JADS and WPM), three sucrose concentrations (8, 10 and 12 g L-1) and three agar concentrations (15, 30 and 45 g L-1), with three replicates each and experimental units composed of one plant per replicate. After 25 days of cultivation, the fresh and dry mass of the plants, numbers of leaves, numbers of nodes, plant lengths, numbers of oxidised leaves, hyperhydricity and acclimatization percentages were evaluated. The WPM medium resulted in a reduced fresh mass, reflecting in the low hyperhydricity observed in the explants, and favoured the acclimatization of the plants. Thus, the WPM medium with sucrose (15 g L-1) and agar (12 g L-1) is recommended as the medium most suitable for the in vitroregeneration of Aloysia triphylla.

Growth inhibition and morphological alterations of Staphylococcus aureus caused by the essential oil of Aloysia triphylla / Inhibición del crecimiento y alteraciones morfológicas de Staphylococcus aureus causadas por el aceite esencial de Aloysia triphylla

Aloysia triphylla essential oil (EO) has antimicrobial activity on Staphylococcus aureus which is a pathogen responsible for severe infections and food contamination. The target of EO is mainly in the cytoplasmic membrane. In this work the mechanisms of action of the EO of A. triphylla on S. aureus were investigated. A. triphylla was collected from La Paz. The oil was analyzed by GC-MS. The antimicrobial effects were evaluated by MIC, MBC, killing time and TEM. MIC values were 23 μg/mL for 6.3 x 104 CFU/mL, 92 μg/mL for 5.71 x 105 CFU/mL and 180 μg/mL for 9 x 106 CFU/mL. The MBC was 5920 μg/mL for all cellular concentrations and it was necessary more time to kill bigger cell populations. Multilamellar and mesosome-like structures on the membrane were seen by TEM. A. triphylla oil is an antibacterial compound against S. aureus which main mechanism of action seems to be the cytoplasmic membrane disruption.

El aceite esencial (AE) de Aloysia triphylla posee actividad antimicrobiana contra Staphylococcus aureus, patógeno responsable de infecciones nosocomiales e alimenticias. El blanco de acción de los AE es la membrana citoplasmática. El mecanismo de acción del AE de A. triphylla sobre S. aureus fue investigado. El AE de A. triphylla (La Paz, Argentina) fue analizado por CG-EM. Se evaluó́ el efecto antimicrobiano por CIM, CBM, tiempo de muerte y MET. Los valores de CIM fueron 23 μg/mL para 6.3 x 104 UFC/mL, 92 μg/mL para 5.71 x 105 UFC/mL y 180 μg/mL para 9 x 106 UFC/mL. La CBM fue 5920 μg mL para todas las concentraciones celulares estudiadas. El tiempo de muerte fue determinado; necesitando mayor tiempo para matar una población celular elevada. Fueron observados por MET estructuras multilamerales y semejantes a mesosomas. El AE de A. triphylla es un potencial compuesto antibacteriano contra S. aureus donde su principal mecanismo de acción es por disrupción de la membrana citoplasmática.

Chemical composition and antibacterial activity of Aloysia triphylla (L'Hérit) Britton extracts obtained by pressurized CO2 extraction

This study investigated the chemical composition of five different extracts of Aloysia triphylla and their activity against Aeromonas sp. The extracts were obtained from the dried leaves by pressurized CO2 extraction at 30, 50 and 70ºC, and 100, 150, and 200 bar, and analyzed by GC/FID and GC-MS. The antibacterial activity was assayed by the microdilution method. The tested microorganisms comprised seven Aeromonas isolates obtained from the kidney of infected silver catfish, Rhamdia quelen. The yield, chemical composition and antibacterial activity of the extracts were dependent on the extraction conditions. Mono and sesquiterpenoids were the major constituents of all the extracts and the highest extraction yield was obtained at 70ºC and 200 bar. A. triphylla presented moderate antibacterial activity against Aeromonas sp.

Phytochemical Characterization and Radical Scavenging Activity of Aqueous Extracts of Medicinal Plants from Portugal.

Aims: The aim of this study was to evaluate the total phenolic and flavonoid contents of four medicinal plants from Portugal usually consumed as tea infusion, Melissa officinalis (Lamiaceae) – lemon balm, Matricaria chamomilla (Asteraceae) – chamomile, Olea europaea (Oleaceae) – olive leaves, and Aloysia triphylla (Verbenaceae) – lemon verbena. Place and Duration of Study: Air-dried leaves of four of the most consumed medicinal plants from Portugal were analyzed in the Department of Pharmacognosy (UFP) and Laboratory of Bromatology (FFUP) and, Department of Pharmacy, and Chemical Laboratory, Health Technology Research Center (CITS) between June 2010 and September 2011. Methodology: Qualitative phytochemical analysis was done for several phytoconstituents (alkaloids, steroids, terpenoids, flavonoids, and tannins). Total phenolic, flavonoid, and tannin contents were quantified by UV-Vis spectrophotometry. It was also analyzed the possible correlation between antioxidant activity (in vitro) and the synergistic effect between different phytochemicals, using the free radical 2,2’-diphenyl-1-picrylhydrazyl (DPPH). Results: Steroids, terpenoids, flavonoids and tannin, were present in Melissa officinalis and Matricaria chamomilla. In Olea europaea leaves, all the chemical constituents were present except alkaloids, and terpenoids. Aloysia triphylla showed the presence of all the constituents. Total phenol contents ranged from 12.91mg.100g-1 to 87.25 mg.100g-1 and flavonoid contents ranged from 25.17mg.100g-1 to 57.28mg.100g-1. The screening of the leaf of the four selected medicinal plants indicates that the presence of high phenolic content may be due to the presence of tannins and flavonoids which are known to possess antioxidant activities. A slight correlation has been observed between total phenolics and antioxidant activity. Conclusion: Our findings provided evidence that aqueous extracts of these tested plants from Portugal contain medicinally important bioactive compounds. Results showed that plants from Portugal usually used as tea infusions are a good source of phytochemical compounds presenting antioxidant activity, so their consumption must be incremented in younger generations which usually consume other less beneficial drinks.

Antispasmodic effects of Aloysia polystachya and A. gratissima tinctures and extracts are due to non-competitive inhibition of intestinal contractility induced by acethylcholine and calcium

The antispasmodic effects of acqueous extracts (AE) and tinctures (T) of Aloysia polystachya (Griseb.) Moldenke and Aloysia gratissima (Gillies & Hook.) Tronc., Verbenaceae, were studied on rat isolated ileum and duodenum. These plants are used for gastrointestinal disorders and as eupeptic in South America. Both AE non-competitively inhibited the dose-response curves (DRC) of ACh and the DRC of Ca2+ in high-[K+]o, as well as the T. The T of A. polystachya and A. gratissima respectively inhibited the ACh-DRC at the IC50 of 3.15±0.57 and 6.46±2.28 mg leaves/mL. The Ca2+- antagonist activity of both T occurred with IC50 respectively similar to those of the ACh-DRC, and was potentiated by the depolarization produced by 10 mM TEA, a blocker of K+- channels. The spasmolytic effect of T does not involve DA release and binding to D2, since it was not reduced by 10 µ M metoclopramide. Also, T induced dose-dependent relaxation on the tonic contracture produced by high -[K+]o and ACh. By TLC there were detected in the leaves the presence of carvone, and flavonoids such as quercetin and hesperidin. By HPLC there were not found vitexin nor isovitexin, identified in A. citriodora. The monoterpene (-)- carvone non-competitively inhibited the ACh-DRC (pD'2 of 4.0±0.1) and the DRC of Ca2+ (pD'2 of 3.86±0.19), suggesting that the Ca2+- influx blockade is the mechanism of its antispasmodic effect. Results suggest that the antispasmodic effect of A. polystachya and A. gratissima are mostly explained by the non-competitive blockade of Ca+2 influx. It could be associated to the presence of flavonoids, and in the tinctures to some spasmolytic components of the essential oil such as carvone.

Dinámica de polifenoles de “Cedrón” (Aloysia citrodora Palau -Verbenaceae-) en relación al desarrollo foliar / Polyphenol dinamics on “cedrón” (Aloysia citrodora Palau -Verbenaceae-) according to leave development

Leaf infusions from Aloysia citrodora Palau –Verbenaceae-, known as “cedrón” were analyzed in order to establish the possible influence of their development on polyphenols profile. Chromatographic fingerprints of infusions from young and full expanded leaves were performed and total phenols, total tannins, total flavonoids and total hydroxycinnamic acids were quantified. Young leaves had significative higher total phenols, total flavonoids and total hydroxycinnamic acids concentrations than full expanded leaves. This research suggest that the analyzed parameter should be considered when elaborating products from “cedrón” leaves, as the variation in compound concentration may translate in different biological activities.

Se analizaron las infusiones realizadas a partir de las hojas de Aloysia citrodora Palau –Verbenaceae-, conocida vulgarmente como “cedrón”, con el objeto de establecer la influencia del grado de desarrollo foliar en el perfil de polifenoles. Se obtuvieron los perfiles cromatográficos y se cuantificaron los fenoles totales, taninos totales, flavonoides totales y ácidos hidroxicinámicos totales provenientes de los extractos acuosos de las hojas jóvenes y adultas. Se observaron diferencias cuali-cuantitativas en el perfil de polifenoles cuando se comparan las hojas jóvenes con las hojas adultas. En las hojas jóvenes, las concentraciones de fenoles totales, flavonoides totales y ácidos hidroxicinámicos totales resultaron ser significativamente superiores a las determinadas en las hojas adultas. Los estudios realizados sugieren que la variable aquí analizada debe ser considerada al momento de elaborar productos en base a hojas de cedrón, dado que las diferentes concentraciones detectadas podrían traducirse en diferentes actividades biológicas.

Análisis de polifenoles, actividad antioxidante y genotoxicidad en especies argentinas de Lippia y Aloysia (Verbenaceae) / Survey on polyphenols, antioxidant activity and genotoxicity on Argentinean species of Lippia and Aloysia (Verbenaceae)

Three species and a variety from the Verbenaceae belonging to the argentinean flora were analyzed: Aloysia gratissima var. gratissima (Gill. Et Hook) Tronc., Aloysia gratissima var. schulziana (Moldenke) Botta, Aloysia polystachya (Griseb.) Moldenke and Lippia integrifolia (Griseb.) Hieron., the first two known as “cedrón del monte”, the third as “yerba del burro” and the other as “incayuyo”. Their leaves are used as digestive in folk medicine. The research was performed on quantification of polyphenols (total phenols, total flavonoids and total hydroxicinnamic acids) and on determination of antioxidant and genotoxic activities. L. integrifolia showed the highest total phenol concentration and A. polystachya the lowest, but with the highest concentration of hydroxicinnamic acids. When flavonoids were quantified, A. polystachya showed the lowest concentations and A. gratissima var. schultziana the highest. According to quantification of total polyphenols, the lowest antioxidant activity was measured in A. polystachya extracts, followed by those from A. gratissima var. gratissima and A. gratissima var. schulziana, while extracts from L. integrifolia showed the highest antioxidant activity. No genotoxic activity was detected by means of the comet-assay for any of the species. This absence of genotoxicity, added to the relevant antioxidant activity, could justify the use of leaves infusions and decoctions from these species in treatments of those pathologies where antioxidants play an important role. These studies suggest their sure use in folk medicine, in which people include them among their medicinal plants.

Se analizaron 3 especies y una variedad de la familia Verbenaceae de la flora argentina: Aloysia gratissima var. gratissima (Gill. Et Hook) Tronc., Aloysia gratissima var. schulziana (Moldenke) Botta, Aloysia polystachya (Griseb.) Moldenke y Lippia integrifolia (Griseb.) Hieron., conocidas como “cedrón del monte” las dos primeras, “yerba del burro” la tercera e “incayuyo” la restante. De todas ellas se emplean las hojas en la medicina popular como digestivas. Se investigaron los contenidos de polifenoles (fenoles totales, flavonoides totales y ácidos hidroxicinámicos totales) y se determinó la capacidad antioxidante y genotoxicidad de las preparaciones acuosas (infusiones y cocimientos). L. integrifolia fue la especie con mayor contenido de fenoles totales y A. polystachya la menor. En el análisis de los hidroxicinámicos, A. polystachya fue la que mayor concentración mostró. En cuanto a los flavonoides, A. polystachya fue la que poseyó menor concentración en tanto que A. gratissima var. schultziana fue la más rica en estos compuestos. A. polystachya es la especie que presenta los menores valores de actividad antioxidante, seguida por A. gratissima var. gratissima y A. gratissima var. schulziana, mientras que L. integrifolia es la especie con mayor actividad antioxidante, en correlación con los valores de polifenoles totales. Ninguna de las especies analizadas demostró actividad genotóxica en el ensayo del cometa. La ausencia de genotoxicidad, sumada a una marcada actividad antioxidante, justificarían el empleo de las infusiones y cocimientos en el tratamiento de aquellas patologías donde los agentes antioxidantes juegan un importante rol terapéutico. Estos estudios sugieren el empleo seguro en la medicina tradicional de los pueblos y comunidades que las incluyen entre sus plantas medicinales.

Cytogenetic characterization of Aloysia virgata Ruiz and Pavan (Verbenaceae)

Since previous cytogenetic reports of Aloysia have only described the meiotic behavior and chromosomal number of some species, the aim of this work was to provide detailed cytogenetic description of Aloysia virgata that would contribute to the understanding of the taxonomical organization of the Verbenaceae. Aloysia virgata had a karyotype with 2n = 36 metacentric chromosomes, all with similar size. The large amount of heterochromatin seen after Giemsa staining was confirmed by C-banding. Four nucleolar organizer regions (NORs) were detected with an rDNA 45S probe in two homologous pairs and two sites of 5S rDNA located on one chromosomal pair were detected by fluorescence in situ hybridization. The interphase nucleus was classified as semi-reticulate. Meiotic analysis showed a normal chromosomal behavior, with 18 bivalents in some parts of prophase I and in metaphase I. The number of chromosomes, NORs and 5S rDNA segments did not exclude a possible polyploid origin.

O gênero Aloysia reúne aproximadamente 30 espécies, porém sua circunscrição tem sido motivo de controvérsia. São poucos os estudos citogenéticos para o gênero, relatando apenas o número e o comportamento cromossômico. O presente trabalho teve como objetivo, identificar os caracteres citogenéticos de Aloysia virgata da flora brasileira que possam ser utilizados para um melhor entendimento e caracterização dos aspectos citogenéticos da família Verbenaceae, que possam contribuir para a organização taxonômica do grupo. Aloysia virgata apresentou cariótipo com 2n = 36 pequenos cromossomos, todos com o mesmo tamanho. Grande quantidade de heterocromatina foi observada com Giemsa e confirmada pela técnica de banda C. Foram detectadas quatro regiões organizadoras de nucléolo (NORs) e dois sítios de rDNA 5S pela técnica de hibridação in situ fluorescente (FISH). O núcleo interfásico foi classificado como semireticulado. Foi realizada a caracterização meiótica, na qual os cromossomos apresentaram comportamento normal, com a presença de 18 bivalentes na prófase I e na metáfase I. O número de cromossomos, de NORs e de segmentos de DNAr 5S não excluem uma possível origem poliplóide.

Teores do óleo essencial de cidrão [Aloysia triphylla (L'Hérit) Britton (Verbenaceae)] em diferentes horários de colheita e processamentos pós-colheita / Lemon verbena's [Aloysia triphylla (L'Hérit) Britton (Verbenaceae)] essential oil content in different harvest periods and post-harvesting process

Este estudo foi realizado com o objetivo de avaliar o teor do óleo essencial de cidrão [Aloysia triphylla (L´Hérit) Britton] em diferentes horários de colheita e processamentos pós-colheita. O delineamento utilizado foi inteiramente casualizado. As colheitas foram realizadas em três horários distintos (8 h, 12 h e 16 h), com três repetições. Os processamentos pós-colheita foram cinco: T1- folhas frescas fragmentadas em 1cm; T2- folhas frescas processadas em liquidificador; T3- folhas frescas inteiras; T4- folhas secas inteiras; T5- folhas secas pulverizadas em moinho, com três repetições. O óleo essencial de cada tratamento foi extraído pela técnica de hidrodestilação, utilizando o aparelho modificado de Clevenger, por uma hora e trinta minutos. Os horários de colheita quando se detectou maior teor de óleo foram 8 h e 16 h. Os maiores teores de óleo essencial foram encontrados em folhas frescas fragmentadas em 1cm, folhas frescas processadas em liquidificador, folhas frescas inteiras e folhas secas inteiras.

This study was carried out in order to evaluate the essential oil content of lemon verbena at different harvest times and post-harvest processings. The experimental design used was completely randomized. The harvested material was collected at three different hours (8:00, 12:00 and 16:00 pm), and it was taken three times. In post-harvest processings, three replications and five treatments were us do: 1 cm fresh leaf fragments, blended fresh leaves, whole fresh leaves, whole dry leaves and dry leaves ground in mill. The essential oil was determined in Clevenger's modified apparatus for 1 hour and 30 minutes. The periods of the day that detected high essential oil content were at 8:00 am and 16:00 pm. The high essential oil level was in 1 cm fresh leaf fragments, blender processed fresh leaves, whole fresh leaves and whole dry leaves.