Microwave and ultrasound extraction of antioxidant phenolic compounds from Lantana camara Linn. leaves: Optimization, comparative study, and FT-Orbitrap MS analysis.

INTRODUCTION: The species Lantana camara is used in folk medicine. The biological activities of this medicinal plant are attributable to the presence of various derivatives of triterpenoids and phenolic compounds present in its preparations, indicating excellent economic potential. OBJECTIVE: In this study, the operational conditions of ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) were optimized using Box-Behnken design to improve the total phenolic content (TPC) recovered in hydroethanolic extracts of L. camara leaves. MATERIAL AND METHODS: The TPC, total flavonoid content (TFC), and antioxidant activities of the hydroalcoholic extracts of L. camara, prepared by UAE and MAE under the optimized extraction conditions, were compared with those of the extracts obtained by conventional extraction methods. RESULTS: Under the optimal conditions, the extracts obtained by UAE (35% ethanol, 25 min, and a solvent-to-solid ratio of 60:1 mL/g) and by MAE (53% ethanol, 15 min, and 300 W) provided high yields of 32.50% and 38.61% and TPC values of 102.89 and 109.83 mg GAE/g DW, respectively. The MAE extract showed the best results with respect to TPC, TFC, and antioxidant activities, followed by extracts obtained by UAE, Soxhlet extraction, decoction, maceration, and infusion, in that order. CONCLUSION: The results obtained indicate that L. camara may be used as an important source of antioxidant phenolic compounds to obtain products with high biological and economic potential, especially when the extraction process is performed under appropriate conditions using MAE and/or UAE, employing environmentally friendly solvents such as water and ethanol.

Chemical characterization and antimicrobial activity of essential oils from Croton grewioides Baill. accessions on the phytopathogen Xanthomonas campestris pv. campestris.

Croton grewioides Baill. is an aromatic species with proven bioactive properties. Considering the potential of the species, the aim of this study was to chemically characterize and evaluate the in vitro antibacterial activity of the essential oils of C. grewioides on Xanthomonas campestris pv. campestris. The essential oils of the accessions of C. grewioides were extracted by the hydrodistillation method and analyzed by gas chromatography - mass spectrometry. For determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the essential oils and of the compound eugenol, the microdilution method was used at concentrations that ranged from 125 to 4000 µg.mL-1. Streptomycin sulfate was used as a positive control (12.5 to 100 µg.mL-1). Growth kinetics and the membrane permeability trial were evaluated for the concentrations 2×, 1×, 1/2×, 1/4×, and 1/8× MIC of the essential oil CGR-108. The major compounds identified in the essential oils were eugenol, methyl eugenol, and methyl chavicol. The essential oil of the accession CGR-108 had a lower MIC (> 500 and < 1000 µg.mL-1) and MBC equal to <2000 µg.mL-1. For eugenol, MIC was obtained with contractions >250 and < 500 µg.mL-1 and MBC with >500 µg.mL-1 and < 1000 µg.mL-1. A loss of cell viability of the bacteria was observed after 30 min of exposure to the essential oil of the accession CGR-108 at the concentrations of 2× and 1× MIC, which was proven by the fluorescence intensity with propidium iodide. The essential oils of Croton grewioides Baill. and the compound eugenol show antibacterial potential on Xanthomonas campestris pv. campestris.

Bioactivity of essential oils from Croton grewioides and its major compounds: toxicity to soybean looper Chrysodeixis includens and selectivity to the predatory stink bug Podisus nigrispinus.

Natural biological control is a key factor that ensures the regulation of insect pest populations in agroecosystems. However, the indiscriminate use of pesticides has compromised this environmental service. Thus, the search for environmentally safe pesticides is an increasing requirement for sustainable food production. In this study, we analyzed the toxicity of essential oils from two accessions (CGR112 and CGR126) of Croton grewioides and its major compounds, methyl eugenol and eugenol, on the soybean pest Chrysodeixis includens. In addition, we investigated the sublethal effects of these compounds on the predatory bug Podisus nigrispinus, analyzing its developmental, reproduction and life table parameters. Essential oils and their major compounds were toxic to C. includens and P. nigrispinus. In general, the presence of eugenol made the essential oil more toxic to the pest and selective to the natural enemy. Eugenol was the most toxic compound for 2nd instar larvae of C. includens at LD50, followed by CGR126 essential oil from C. grewioides which was equally toxic at higher doses. The estimated lethal times for essential oils to cause mortality in 50% of the population of C. includens were less than 15 h. There was selectivity of the essential oil of CGR126 accession of C. grewioides at lethal doses above 90%. Although the treatments showed little effect on the development of P. nigrispinus, body mass and reproductive parameters were negatively affected, with the exception of the essential oil of CGR126 accession of C. grewioides. The essential oil of C. grewioides may be a promising active ingredient for the synthesis of new insecticides, which are efficient against C. includens and at the same time are safer for the natural enemy P. nigrispinus.

Lippia alba and Lippia gracilis essential oils affect the viability and oviposition of Schistosoma mansoni.

Schistosomiasis is a neglected tropical disease that affects millions of people around the world. Currently, the only drug available for the treatment of this disease is praziquantel, which has low efficacy against immature helminth stages and there are reports of drug resistance. In this study, the chemical composition and the in vitro effect of essential oils (EOs) and major compounds from Lippia gracilis and Lippia alba against schistosomula and adult Schistosoma mansoni worms were evaluated. Adult S. mansoni worms cultured for 8h in the presence of L. gracilis EO (50 and 100 µg/mL) or for 2h with its major compound, carvacrol (100 µg/mL), had a 100% reduction in viability. After interaction with L. alba EO (100µg/mL), there was a reduction of approximately 60% in the viability of adult worms after 24 hours of exposure; citral (50 and 100 µg/mL), its major compound, reduced the viability after 24 hours by more than 75%. Treatment of schistosomula with 100 µg/mL of L. gracilis or L. alba EOs for 6h led to a reduction in parasite viability of 80% and 16% respectively. Both EOs and their major compounds significantly reduced the oviposition of adult worms exposed to a non-lethal concentration (5 µg/mL). In addition, morphological changes such as the destruction of the tegument and disorganization of the reproductive system of male and female worms were visualized. Both EOs showed low cytotoxicity at a concentration of 50 µg/mL. The results encourage further investigation of these plants as a potential source of bioactive compounds against S. mansoni.

Production and composition of Lavender oil: nutritional management and cultivation systems / Producción y composición de aceite de lavanda: manejo nutricional y sistemas de cultivo

The objective was to evaluate the production and composition of lavender essential oil, simultaneously at open field and greenhouse, in spring-summer season, under different types of fertilization. Each cultivation system was considered an experiment (field and greenhouse), and in both, the experimental design used was randomized blocks, with five treatments, being fertilization with nutrient source -100% mineral (100%M), 100% organic (100%O), 100% organomineral (100%OM), 50% organomineral (50%OM), and without fertilization (control), and three repetitions. Better performance and productivity of Lavandula dentatais related to respectively 100% OM and 50% OM fertilization in the field and greenhouse. The essential oil content does not differ between cultivation systems and kind of fertilizers, and the majorities compounds were 1.8-cineol, fenchone and camphor.

El objetivo fue evaluar la producción y composición del aceite esencial de lavanda a campo abierto e invernadero simultáneamente, en la temporada primavera-verano, bajo diferentes tipos de fertilización. Cada sistema de cultivo fue considerado un experimento (campo e invernadero), y en ambos, el diseño experimental utilizado fue bloques al azar, con cinco tratamientos, siendo la fertilización con fuente de nutrientes 100% mineral (100% M), 100% orgánico (100% O), 100% organomineral (100% MO), 50% organomineral (50% MO), y sin fertilización (control), y tres repeticiones. Un mejor rendimiento y productividad de Lavandula dentata está relacionado con una fertilización de 100%OM y 50% OM en el campo y en invernadero, respectivamente. El contenido de aceite esencial no difiere entre sistemas de cultivo y tipo de fertilizante, y los compuestos mayoritarios fueron 1.8-cineol, fenchone y alcanfor.

Effects of acaricidal essential oils from Lippia sidoides and Lippia gracilis and their main components on vitellogenesis in Rhipicephalus microplus (Canestrini, 1888) (Acari: Ixodidae).

Rhipicephalus microplus is an important cattle tick, and resistant strains to synthetic compounds have been widespread. The combined effects of different essential oil compounds enhance biological activity and reduce selection for the development of target organism resistance. Essential oils of two different genotypes of each of Lippia sidoides and Lippia gracilis and their main components, the isomers thymol and carvacrol, have acted as acaricides against R. microplus. Little is known about the effects of the essential oils of L. sidoides and L. gracilis and thymol and carvacrol on the morphophysiology of R. microplus ovaries. This study aimed to identify the morphological changes in the ovaries of R. microplus females treated with essential oils from two different genotypes of each of L. sidoides (102 and 103) and L. gracilis (106 and 201) and the terpenes thymol and carvacrol through histological techniques. The LC50 and LC75 of essential oils and thymol and carvacrol were used for Adult Immersion Test (AIT) with groups of five fully engorged females of R. microplus. A negative control (DMSO 3% solution) was performed. Seven days after the AIT, the ticks were dissected to collect ovaries and their histologic analysis. Only the group treated with the essential oil of L. gracilis genotype 106 at the LC50 had no change compared with the control. The other groups showed the following changes in oocytes I to V: vacuolation, chorion deformation, disorganization of yolk granules, and irregularities at the cell periphery, causing incomplete process of vitellogenesis. Thus, the essential oils tested in this study may be potent products for the control of cattle ticks and thereby preventing further life cycles.

Antibacterial activity of Lippia alba, Myrcia lundiana and Ocimum basilicum essential oils against six food-spoiling pathogenic microorganisms / Actividad antibacteriana de los aceites esenciales de Lippia alba, Myrcia lundiana y Ocimum basilicum contra seis microorganismos patógenos que estropean los alimentos

The aim of this study was to undertake a screening experiment on essential oils (EO) of Myrcia lundiana, Ocimum basilicum and Lippia alba against six food-spoiling pathogenic bacteria. Seventy-two (72) samples were initially analyzed fo antimicrobial activity based on the agar diffusion test. The minimum inhibitory (MIC) and bactericidal (MBC) concentrations were determined for the 12 samples which showed greatest antimicrobial potential in this stage. Two samples of L. alba, three samples of M. lundiana and seven samples of O. basilicum showed a MIC of 0.12-125 µL/mL for the six tested bacteria. Of these, the EO of O. basilicum cultivar Maria Bonita stood out with the lowest MIC and MBC. Thus, a mixture simulating this essential oil was prepared from commercial standards of the compounds (±)-linalool, geraniol and 1,8-cineole. Significantly higher MIC and MBC were detected in the simulation compared to the respective EO, suggesting a synergistic effect between compounds.

El objetivo de este estudio fue realizar un experimento de detección en aceites esenciales (AE) de Myrcia lundiana, Ocimum basilicum y Lippia alba contra seis bacterias patógenas que estropean los alimentos. Setenta y dos (72) muestras fueron analizadas inicialmente para la actividad antimicrobiana basada en la prueba de difusión en agar. Se determinaron las concentraciones mínimas inhibitoria (CMI) y bactericida (CMB) para las 12 muestras que mostraron el mayor potencial antimicrobiano en esta etapa. Dos muestras de L. alba, tres muestras de M. lundiana y siete muestras de O. basilicum mostraron un CMI de 0.12-125 µL/mL para las seis bacterias analizadas. De estos, el AE de O. basilicum cultivar Maria Bonita se destacó con el CMI y CMB más bajos. Por lo tanto, se preparó una mezcla que simula este aceite esencial a partir de los estándares comerciales de los compuestos de (±)-linalol, geraniol y 1,8-cineol. Se detectaron CMI y CMB significativamente más altos en la simulación en comparación con el AE respectivo, lo que sugiere un efecto sinérgico entre los compuestos.

Potential source of ecofriendly insecticides: Essential oil induces avoidance and cause lower impairment on the activity of a stingless bee than organosynthetic insecticides, in laboratory.

The negative effect of insecticides on bees has been reported as one of the factors associated with the decline in population of these pollinators. Thus, the aim of this study was to evaluate the response of the stingless bee Nannotrigona aff. testaceicornis (Lepeletier, 1836) to a promising source of new insecticide molecules obtained from Lippia sidoides (rosemary pepper) essential oil (EO) and its major compounds (thymol, ρ-cymene, and (E)-caryophyllene), comparing them to commercial insecticides (organosynthetic: imidacloprid, deltamethrin and semisynthetic: spinetoram). For this, stingless bees were exposed by contact with these compounds to evaluate the lethal and sublethal (locomotion and flight orientation) toxicity. The L. sidoides EO and its major compounds have low lethal toxicity to forager worker bees (N. aff. testaceicornis). The organosynthetics imidacloprid (LD50 =0.00146 µgbee-1) and deltamethrin (LD50 =0.0096 µg bee-1) were about 209,589 and 31,875 times more toxic, respectively, than the least toxic natural compound, (E)-caryophyllene (LD50 =306 µgbee-1). Locomotion ability and flight orientation were little affected by spinetoram and by L. sidoides EO and its major compounds, however, were greatly reduced by the imidacloprid and deltamethrin insecticides. Besides shows low lethal and sublethal toxicity, the bioinsecticides were also avoided by the forager bees. Individuals treated with the L. sidoides EO and thymol were avoided by the untreated bees. Therefore, the natural products studied here were promising due to their recognized effectiveness against pest insects and greater safety to bees N. aff. testaceicornis.

A comparative study of the antifungal activity of essential oils of Varronia curassavica Jacq. obtained by different distillation methods / Estudo comparativo da atividade antifúngica dos óleos essenciais de Varronia curassavica Jacq. obtidos por diferentes métodos de destilação

This work aimed to compare the antifungal activity of the essential oil of Varronia curassavica obtained by hydrodistillation and microwave against the fungus Colletotrichum musae and verify the alterations caused by these extraction methods on the leaf surface. This study used four essential oil samples obtained by different methods, two by hydrodistillation [HD1 (1.0 L of water and 100 min.) and HD2 (2.0 L of water and 140 min.)] and two by microwave [MI1 (500W, 20 min, without water) and MI2 (700W, 40 min, with 50 mL of water added to fresh leaves)]. Essential oils concentrations of 0.05, 0.1, 0.5, 1.0, and 3.0% (v / v) were tested in PDA medium. The mycelial growth of C. musae was evaluated by measuring the diameter, every 24 hours up to 144 hours after the beginning of the incubation. Untreated leaves and leaves treated with HD1 and MI1 were prepared for observation in a scanning electron microscope (SEM) LEO EVO 40. The most abundant compounds detected in the essential oil samples analyzed by gas chromatography were: shyobunol, germacrene D-4-ol, E-caryophyllene, bicyclogermacrene, and α-cadinol. Up to 72 hours after the beginning of the incubation, C. musae presented no mycelial growth, even at the lowest essential oil concentration. Conversely, mycelial growth was detected in the control (PDA + DMSO) from 24 hours after incubation. At 144 hours after incubation, regardless of the concentration, the essential oil samples obtained by HD provided lower mycelial growth of C. musae (1.49 cm) when compared with samples obtained by MI (1.80 cm). This difference possibly occurred due to the reduction to less than half of the germacrene D-4-ol content in the samples obtained by MI. The four essential oil samples tested inhibited the mycelial growth and thus presented a inhibitory effect on C. musae. The SEM revealed more drastic changes on the surface of the leaf treated with MI than on those treated with HD. The essential oil of V. curassavica, mainly when obtained by hydrodistillation, has the potential for use in the control of C. musae.

O objetivo do trabalho foi comparar a atividade antifúngica do óleo essencial de Varronia curassavica obtido por hidrodestilação e micro-ondas frente ao fungo Colletotrichum musae e verificar as alterações que esses métodos de extração causam na superfície da folha. Quatro amostras de óleo essencial obtidas em diferentes condições foram utilizadas. Sendo duas por hidrodestilação, HD1 (1,0 L de água e 100 min.) e HD2 (2,0 L de água e 140 min.); e duas por micro-ondas, MI1 (500W, 20 min. sem adição de água) e MI2 (700W, 40 min. com adição de 50 mL de água às folhas frescas). Foram testadas as concentrações 0,05; 0,1; 0,5; 1,0 e 3,0 % (v/v) de óleo essencial em meio BDA. O crescimento micelial do C. musae foi avaliado por medições do diâmetro, a cada 24 horas até 144 horas após o início da incubação. Folhas sem qualquer tratamento e após os tratamentos HD1 e MI1 foram preparadas para observação em microscópio eletrônico de varredura (MEV) LEO EVO 40. Os compostos mais abundantes nas amostras de óleo essencial analisadas por cromatografia gasosa foram: shyobunol, germacreno D-4-ol, E-cariofileno, biciclogermacreno e α-cadinol. Até 72 horas após o início da incubação, não foi observado nenhum crescimento micelial do C. musae, mesmo nas concentrações mais baixas de óleo essencial, enquanto, para o controle (BDA + DMSO), foi observado crescimento do fungo a partir de 24 horas. Após 144 horas, independentemente da concentração, as amostras de óleo essencial obtidas por HD proporcionaram menor crescimento micelial do C. musae (1,49 cm) quando comparadas às amostras obtidas por MI (1,80 cm). Possivelmente essa diferença ocorreu devido à redução para menos da metade, do teor de germacreno D-4-ol, nas amostras obtidas por MI. As quatro amostras de óleo essencial testadas foram capazes de inibir o crescimento micelial, apresentando portanto, um efeito inibitório sobre o C. musae. Alterações mais drásticas observadas através da MEV foram visualizadas na superfície da folha submetida ao processo de extração por MI em comparação à HD. O óleo essencial de V. curassavica, sobretudo o obtido por hidrodestilação, apresenta potencial para o controle de C. musae.

Chemical Profile and Use of the Peat as an Adsorbent for Extraction of Volatile Compounds from Leaves of Geranium (Pelargonium graveolens L' Herit).

Volatile organic compounds (VOCs) from leaves of geranium (Pelargonium graveolens L' Herit) were extracted by dynamic headspace using Porapak Q (HSD-P) as adsorbent and peat, a novel adsorbent in the extraction of plant volatiles, analyzed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography-flame ionization (GC/FID), and the results were compared with those obtained by hydrodistillation (HD). The yield volatiles changed with the extraction method. HD was more efficient for extracting linalool (11.19%) and citronellyl formate (9.41%). Citronellol (28.06%), geraniol (38.26%) and 6,9-guaiadiene (9.55%) and geranyl tiglate (8.21%) were the major components identified by dynamic headspace using peat (HSD-T), while citronellol (16.88%), geraniol (13.63%), 6,9-guaiadiene (16.98%) and citronellyl formate (6.95%) were identified by dynamic headspace using Porapak Q (HSD-P). Furthermore, this work showed, for the first time, that in natura peat is useful to extract VOCs from leaves of geranium.

Influence of storage temperatures and storage time of dry leaves on patchouli [Pogostemon cablin (Blanco) Benth. ] essential oil / Influência do tempo e temperaturas de armazenamento das folhas secas no óleo essencial de patchouli [Pogostemon cablin (Blanco) Benth. ]

Patchouli [Pogostemon cablin (Blanco) Benth.] is a plant of the family Lamiaceae, widely used as an essential oil in the cosmetics and perfumery industry. This study aimed to evaluate the influence of storage time and temperature of dry leaves on the patchouli essential oil content and chemical composition. The experiment was performed in a completely randomized design in a 6x2x2 factorial scheme, testing storage time (0, 1, 2, 4, 8, and 16 weeks) and temperature (28°C and 33°C) of dry leaves of two patchouli genotypes (POG-015 and POG-021). The variables essential oil content and chemical composition, and the identification of fungus during storage were evaluated. Results showed that the storage significantly influenced the essential oil content. Patchoulol was identified as the major compound in both genotypes, ranging from 55.05% to 68.77% (POG-15) and from 52.83% to 64.06% (POG-021). Based on the results of patchoulol, dry leaves of both genotypes (POG-015 and POG-021) can be stored for up to eight weeks at 28- 33°C without altering the essential oil quality.

Patchouli [Pogostemon cablin (Blanco) Benth.] é uma planta pertencente à família Lamiaceae, e seu óleo essencial é utilizado nas indústrias de perfumes e cosméticos. O objetivo do trabalho foi avaliar a influência do tempo e temperaturas de armazenamento das folhas secas no teor e na composição química do óleo essencial de patchouli. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 6x2x2, testando tempo de armazenamento (0, 1, 2, 4, 8 e 16 semanas), temperatura de armazenamento (28°C e 33°C) de folhas secas de dois genótipos (POG-015 e POG-021) de patchouli. As variáveis avaliadas foram o teor e a composição química do óleo essencial e a identificação dos fungos que se desenvolveram durante o armazenamento. Os resultados mostraram que o armazenamento influenciou significativamente o teor de óleo essencial. Dos compostos identificados, o patchoulol foi o composto majoritário nos dois genótipos, variando de 55,05% a 68,77% (POG-15) e 52,83% a 64,06% (POG-021). Baseado no patchoulol, folhas secas dos genótipos (POG-015 e POG-021) de patchouli podem ser armazenadas por um período de até oito semanas em temperatura de 28 e 33°C, sem alterar a qualidade do óleo essencial.

Morphoagronomic characterization of Lantana camara L. germplasm / Caracterização morfoagronômica de germoplasma de Lantana camara L

The medicinal and aromatic species Lantana camara is a bush that receives a lot of interest regarding ornamental use. However, due to its condition of invasive plant in natural environments, it suffers constant eradication attempts, which causes genetic erosion of the species. To work around this problem, a sample of the genetic variability of L. camara was saved in the Active Germplasm Bank of medicinal and aromatic plants of the Federal University of Sergipe (UFS). This study aimed to evaluate morphoagronomically 22 accessions of L. camara, collected in 15 municipalities in the state of Sergipe. To carry out morphoagronomic characterization, morphological and agronomic traits were analyzed. Phenotypic variability among the accessions of the L. camara collection for all the analyzed morphological quantitative and agronomic characteristics was observed. The means ranged from 4.91 to 6.90 cm for leaf length; from 2.81 to 5.03 cm for leaf width; from 1.32 to 1.87 for the leaf length/width ratio; from 9.59 to 22.98 mm2 for leaf area; from 99.00 to 215.00 cm for crown diameter; from 85.67 to 214.33 for plant height; and from 1.08 to 2.43 cm for stem diameter. Most accessions presented erect form. The mean number of flowers per inflorescence varied from 12 to 38 flowers. For the agronomic traits, we observed that the dry mass ranged from 49.86 to 649.04 g.plant-1. The mean content of essential oil ranged from 0.13 to 0.26% and yield between 0.10 and 1.55 mL.plant-1. The most divergent phenotypic accessions were LAC-001 (São Cristóvão) and LAC-038 (Moita Bonita) and the ones with the lowest divergence were LAC-004 (Itaporanga D'ajuda) and LAC-019 (Siriri). Thus, it was observed that the variables were efficient to differentiate the accessions and suggest the existence of genetic variability among them.

A espécie aromática e medicinal Lantana camara, é um arbusto muito usado para ornamentação. Devido à sua condição de planta invasora em ambientes naturais, sofre com tentativas de erradicação constantes, o que ocasiona erosão genética da espécie. Para contornar essa problemática, uma amostra da variabilidade genética da L. camara está sendo conservada no Banco Ativo de Germoplasma (BAG) de Plantas Medicinais e Aromáticas da Universidade Federal de Sergipe (UFS). Assim, objetivou-se com o presente trabalho avaliar morfoagronomicamente 22 acessos de L. camara, coletados em 15 municípios do estado de Sergipe. Para caracterização morfoagronômica, variáveis morfológicas e agronômicas foram analisadas. Observou-se variabilidade fenotípica entre os acessos da coleção de L. camara para a maioria das características morfológicas quantitivas e agronômicas. A média para comprimento de folha variou de 4,91 e 6,90 cm; largura de folha de 2,81 a 5,03 cm; relação comprimento/largura de 1,32 a 1,87; área folia de 9,59 a 22,98 mm²; diâmetro da copa de 99, 00 a 215,00 cm; altura de planta de 85,67 a 214,33 cm; diâmetro do caule de 1,08 a 2,43 cm; A maioria dos acessos apresentou porte ereto. O número médio de flores por inflorescências variou de 12 a 38. Para as características agronômicas observou-se que a massa seca variou de 49,86 a 649,04 g.planta-¹. A média para teor de óleo essencial variou de 0,13 a 0,26% e o rendimento entre 0,10 a 1,55 mL.planta-¹. Os acessos mais divergentes fenotipicamente foram LAC-001 (São Cristóvão) e LAC-038 (Moita Bonita) e os que apresentaram a menor divergência foram LAC-004 (Itaporanga D'ajuda) e LAC-019 (Siriri). Dessa forma, nota-se que as variáveis foram eficientes para diferenciar os acessos e sugerem a existência de variabilidade genética entre eles.

Toxicity of the essential oil of basil cultivars and hybrids and its repellent effect on stored grain pests / Toxicidade do óleo essencial de cultivares e híbridos de manjericão e seu efeito repelente sobre pragas de grãos armazenados

Essential oils have emerged as an alternative to synthetic insecticides in the control of stored grain pests. The toxicity and repellency of the essential oils of four basil cultivars and three basil hybrids and the monoterpenes linalool, citral, and (E)-methyl cinnamate were evaluated in the stored grain pests Callosobruchus maculatus and Sitophillus zeamais. The essential oils of the cultivar Genovese and the hybrid 'Genovese' x 'Maria Bonita' were more toxic to C. maculatus. Conversely, the essential oils of the cultivar Sweet Dani and the hybrid 'Cinnamom' x 'Maria Bonita' were more toxic to S. zeamais. Among the monoterpenes, (E)-methyl cinnamate was the most toxic to both pests, taking 0.14 and 0.34 µ L.mL-1 to kill 50% of the C. maculatus and S. zeamais populations, respectively. All essential oils from cultivars, hybrids, and monoterpenes were repellent to S. zeamais, except for (E)-methyl cinnamate. For C. maculatus, this effect was lower, being citral the most repellent compound. Results demonstrate the insecticidal potential of the essential oil of O. basilicum and its monoterpenes in the control of stored grain pests.

Os óleos essenciais surgem como alternativa aos inseticidas sintéticos no controle das pragas de grãos armazenados. A toxicidade e a repelência dos óleos essenciais de quatro cultivares e três híbridos de manjericão e dos monoterpenos linalol, citral e (E)-cinamato de metila foram avaliadas nas pragas de grãos armazenados Callosobruchus maculatus e Sitophillus zeamais. Os óleos essenciais da cultivar Genovese e do híbrido 'Genovese' x 'Maria Bonita' foram mais tóxicos para C. maculatus. Já para S. zeamais, os óleos essenciais das cultivar Sweet Dani e do híbrido 'Cinnamom' x 'Maria Bonita' apresentaram maior toxicidade. Dentre os monoterpenos, o (E)-cinamato de metila foi o mais tóxico para ambas as pragas. Foram necessários 0,14 e 0,34 µ L.mL-1 para matar 50% da população de C. maculatus e S. zeamais. Todos os óleos essenciais das cultivares, dos híbridos e dos monoterpenos foram repelentes a S. zeamais, com exceção do (E)-cinamato de metila. Já para C. maculatus, este efeito foi reduzido, sendo o citral o composto mais repelente. Nos resultados demonstram o potencial inseticida dos óleos essenciais de O. basilicum e seus monoterpenos para o controle de pragas de grãos armazenados.

Morpho-agronomic characterization of Varronia curassavica germplasm conservated "Ex situ" / Caracterização morfoagronômica de germoplasma de Varronia curassavica conservado "Ex situ"

Varronia curassavica Jacq. is a medicinal and aromatic plant native to Brazil. The essential oil of this species is valued by the pharmaceutical industry due to its bioactive substances containing anti-inflammatory properties. This study aimed to morpho-agronomically characterize 27 accessions of the collection of V. curassavica of the Active Germplasm Bank of Medicinal and Aromatic Plants of the Federal University of Sergipe. The experiment consisted of a randomized block design with three replications. The morphological characterization occurred in the field, by evaluating the variables plant height; canopy width; canopy shape; stem diameter; stem color; leaf blades width, length, and length/width ratio; leaves, petals, and sepals color. The agronomic characterization was performed using the essential oils extracted from dried leaves by hydrodistillation in a Clevenger apparatus. Leaves dry matter yield per plant and essential oil yield and content were also evaluated. The accessions showed great variation for leaves color, with different shades of green, which allowed separating them into dark green leaf and light green leaf plants. Plant height values ranged from 101.33 cm (VCUR-801) to 345.33 cm (VCUR-701). The clustering analysis of the traits revealed seven distinct groups. The accessions VCUR-103 and VCUR-001 were the most divergent, whereas the accessions VCUR-401 and VCUR-404 were the most similar. The morpho-agronomic characterization of V. curassavica accessions provides a correct description of the species by pointing out perspectives for genetic improvement, besides optimizing the conservation process. KEYWORDS: Cordiaceae. Medicinal plant. Aromatic plant. Essential oil. Domestication. Genetic breeding INTRODUCTION Brazil is rich in plant biodiversity (SOUZA et al., 2010). However, in recent years, its biodiversity has undergone accelerated destruction,mainly affecting the natural vegetation. This fact is due to agricultural expansion, fires, logging, extractivism, and uncontrolled urban growth. All these changes have posed a great threat to several plant species in the country (OLIVEIRA, 2010). An alternative for the maintenance and conservation of endangered species is the formationof collections in Active Germplasm Banks, which holds base collections for the conservation of a broad plant genetic variability, enabling biodiversity maintenance (SILVA et al., 2012). Varronia curassavica Jacq. (ex Cordia verbenacea DC.)] is a medicinal and aromatic plant native to Brazil, belonging to the Cordiaceae family (GASPARINO; BARROS, 2009). It occurs from Central America to southern Brazil (LORENZI; MATOS, 2008) in a wide range of habitats, such as beaches, restinga, forests, and cerrado (WANDERLEY et al., 2002). V. curassavica has stood out both in folk medicine and in the pharmaceutical industry, mainly due to the anti-inflammatory substances present in its essential oil (PASSOS et al., 2007; PARISSOTO et al., 2012; PIMENTEL et al., 2012). The effectiveness of V. curassavica is recognized by the National Sanitary Surveillance Agency (ANVISA). The plant is included in the List of the Unified Health System (SUS) and the National List of Medicinal Plants of Interest to the Unified Health System (RENISUS) (BRASIL, 2011). Due to its therapeutic properties, several studies have been developed aimed at the selection Received: 14/05/18 Accepted: 20/11/19

Varronia curassavica Jacq. é uma planta medicinal e aromática nativa do Brasil. O óleo essencial desta espécie é utilizado pela indústria farmacêutica por conter substâncias bioativas com propriedades anti-inflamatórias. Objetivou-se caracterizar morfoagronomicamente 27 acessos da coleção de V. curassavica do Banco Ativo de Germoplasma de Plantas Medicinais e Aromáticas da Universidade Federal de Sergipe. O delineamento experimental foi em blocos casualizados com três repetições. A caracterização morfológica foi realizada em campo, por meio da avaliação da altura da planta; largura da copa; formato da copa; diâmetro do caule a 10 cm do solo; cor do caule; largura, comprimento e relação comprimento/largura das lâminas foliares; e cor das folhas, pétalas e sépalas. A caracterização agronômica foi realizada a partir dos óleos essenciais extraídos de folhas secas por hidrodestilação em aparelho Clevenger. Foi avaliado o rendimento de massa seca das folhas por planta e o teor e rendimento do óleo essencial. Grande variação foi observada entre os acessos para a coloração das folhas, as quais apresentaram diferentes tonalidades de verde, sendo possível separá-las entre plantas com folhas verde-escuro e plantas com folhas verde-claro. Para a variável altura de planta, os valores variaram de 101,33 cm (VCUR-801) a 345,33 cm (VCUR-701). Sete grupos distintos foram formados na análise de agrupamento realizada a partir dos caracteres avaliados. Os acessos VCUR-103 e VCUR-001 foram os que se mostraram mais divergentes, enquanto que os mais semelhantes foram os acessos VCUR-401 e VCUR-404. A caracterização morfoagronômica dos acessos de erva-baleeira permitirá a realização de uma correta descrição da espécie, apontando perspectivas para o melhoramento genético, além de possibilitar a otimização do processo de conservação.

Antifungal activity of essential oils of Myrcia ovata chemotypes and their major compounds on phytopathogenic fungi / Atividade antifúngica de óleos essenciais de quimiotipos de Myrcia ovata e seus principais compostos em fungos fitopatogênicos

This work evaluated the antifungal activity of essential oils of Myrcia ovata chemotypes (MYRO-175, MYRO-156, MYRO-154, MYRO-165, and MYRO-015) and their major compounds (linalool, geraniol, citral, and (E)-nerolidol) on the phytopathogenic fungi Fusarium pallidoroseum (which causes melon postharvest rot) and Colletotrichum musae (which causes anthracnose in banana). The essential oils were obtained by hydrodistillation and analyzed by GCMS/FID. To evaluate the antifungal activity, the essential oils and their major compounds were tested at different concentrations (0.1; 0.3; 0.4; 0.5; 0.7; 1.0; 3.0, and 5.0 mL/L). The major compounds found in the essential oils were nerolic acid, linalool, geraniol, citral, and (E)-nerolidol. The essential oils of the plants MYRO-154, MYRO-165, and MYRO-015 had the minimum inhibitory concentration (MIC) (0.3 mL/L) for F. pallidoroseum and the lowest minimum fungicidal concentration (MFC) (0.7 mL/L), for C. musae. Geraniol and citral had the lowest MFC (0.5 mL / L) for the two fungi tested. For F. pallidoroseum, the essential oils of the chemotypes were more effective than their major compounds. Conversely, the major compounds geraniol of the chemotype MYRO-156 (74.37%) and citral were more effective than their respective essential oils for C. musae. (E)-nerolidol and geraniol of the chemotype MYRO-015 (33.15%) were responsible for the antifungal activity of the essential oils of their respective chemotypes.

No presente trabalho avaliou-se a atividade antifúngica de óleos essenciais de quimiotipos de Myrcia lundiana (MYRO-175, MYRO-156, MYRO-154, MYRO-165, and MYRO-015) e seus compostos majoritários (linalol, geraniol, citral e (E)-nerolidol) sobre os fungos fitopatogênicos Fusarium pallidoroseum(causa podridão em frutos de melão) e Colletotrichum musae (causa antracnose em frutos de banana). Os óleos essenciais foram obtidos hidrodestilação e analisados por CGEM/DIC. Para avaliação da atividade antifúngica foram testados os óleos essenciais e os compostos majoritários nas concentrações: 0,1; 0,3; 0,4; 0,5; 0,7; 1,0; 3,0 e 5,0 mL/L. Os principais compostos presentes nos óleos essenciais foram o ácido nerólico, o linalol, o geraniol, o citral e o (E)-nerolidol. Os óleos essenciais das plantas MYRO-154, MYRO-165 e MYRO-015 apresentaram CIM de 0,3 mL/L e a planta MYRO-015 apresentou a menor concentração fungicida mínima (CFM) (1,0 mL/L). O geraniol e o citral foram os compostos que apresentaram o menor valor de CFM, 0,5 mL/L, frente aos dois fungos testados. O óleo essencial dos quimiotipos testados foram mais promissores que seus componentes majoritários puros, frente o F. pallidoroseum. Já para o C. musae, os componentes majoritários geraniol do quimiotipo MYRO-156 (74,37%) e o citral foram mais promissores que seus respectivos óleos essenciais. Já o (E)-nerolidol e o geraniol do quimiotipo MYRO-015 (33,15%) foram os responsáveis pela atividade antifúngica apresentada pelos óleos essenciais dos respectivos quimiotipos.

Synergistic effect of Cordia curassavica Jacq. essential oils association against the phytopathogen Xanthomonas campestris pv. campestris.

The increased use of pesticides applied to treat diseases caused by bacteria has caused serious environmental problems. There are few fungicides/bactericides for the treatment of plant diseases caused by Xanthomonas campestris pv. campestris (Xcc), and only two natural products with general bactericidal/fungicidal use are available on the market. Thus, this study evaluated the antimicrobial activity of essential oils (EOs), and their combinations, from five distinct genotypes of Cordia curassavica (Jacq.) Roem. & Schult (Syn. Varronia curassavica Jacq.) (CCUR) against Xcc. GC/MS chemical analysis revealed α-pinene, sabinene, (E)-caryophyllene, ar-curcumene, ß-sesquiphellandrene, 7-cyclodecen-1-one, and ar-Turmerone as the major compounds of the five EOs of CCUR. All EOs showed growth inhibition of Xcc with minimum inhibitory concentration between 500 and 1000 µg mL-1. The associations between two EOs from different CCUR genotypes showed that 70% of the total combinations had an additive effect. However, the combinations between CCUR-002 × (-302, -202) and CCUR-302 × (-601) showed a synergistic effect, with mean fractional inhibitory concentration FIC50 values of 0.28, 0.42, and 0.40, respectively. This study demonstrates that combinations of C. curassavica EOs have antimicrobial activity and a potential to be used in the control of black rot. Graphical abstract.

In vitro antifungal activity of Myrcia ovata essential oils and their major compounds against pathogens of citrus, sweet potato, and coconut / Atividade antifungica in vitro de óleos essenciais de myrcia ovata e seus compostos majoritários sobre patógenos de citros, batata-doce e coqueiro

Myrcia ovata, an endemic species to the Brazilian Atlantic Forest, presents antifungal properties. The phytopathogens Colletotrichum acutatum, Plenodomus destruens,and Thielaviopsis paradoxa are responsible for the diseases citrus postbloom fruit drop, sweet potato foot rot, and coconut stem bleeding, respectively. The antifungal activity of the essential oils of five M. ovata chemotypes (MYRO-159, nerolic acid chemotype; MYRO-180, nerolic acid + linalool chemotype; MYRO-388, geraniol chemotype; MYRO-157, citral + (E)-nerolidol chemotype; and MYRO-174, isopulegol + linalool chemotype), four major compounds (nerolic acid, nerolic acid + linalool, geraniol, and citral + (E)-nerolidol), and threepure compounds (citral, (E)-nerolidol, and linalool) against the fungi C. acutatum, P. destruens,and T. paradoxawere evaluated. For this, in vitro tests were conducted in a completely randomized design with three replications, testing concentrations (v/v) ranging from 0.01 to 1.0 µL.mL-1. All treatments presented toxicity at different levels to the three fungi. For C. acutatum,the essential oil from the individual MYRO-180 (nerolic acid + linalool chemotype) and its major compound showed the lowest Minimal Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC) of 0.03 and 0.1 µL.mL-1, respectively. For P. destruens, the essential oil from the individual MYRO-159 (nerolic acid chemotype) presented the lowest MIC of 0.05 µL.mL-1. The nerolic acid + linalool chemotype and its major compound presented an MFC of 0.07 µL.mL-1. For T. paradoxa, the major compound citral + (E)-nerolidol stood out with the lowest MIC and MFC of 0.03 and 0.2 µL.mL-1, respectively. Linalool presented the lowest toxicity to the three tested fungi.

Myrcia ovata, uma espécie nativa de fitofisionomia de Restinga, possui atividade antifúngica. Os fitopatógenos Colletotrichum acutatum, Plenodomus destruens e Thielaviopsis paradoxa são responsáveis pelas doenças podridão floral de citros, mal-do-pé da batata doce e resinose do coqueiro, respectivamente. A atividade antifúngica de cinco quimiotipos de M. ovata (MYRO-159, quimiotipo ácido nerólico; MYRO-180, ácido nerólico + linalol; MYRO-388, quimiotipo geraniol; MYRO-157, quimiotipo citral + (E)-nerolidol; e, MYRO-174, quimiotipo isopulegol + linalol), quatro compostos majoritários (ácido nerólico, ácido nerólico + linalol, geraniol e citral + (E)-nerolidol) e três compostos isolados (citral, (E)-nerolidol e linalol) foram avaliados sobre os fungos C. acutatum, P. destruens e T. paradoxa. Testes in vitro foram conduzidos em delineamento inteiramente casualizado com três repetições e concentrações (v/v), que variaram de 0,01 a 1,0 µL.mL-1. Todos os tratamentos testados apresentaram atividade antifúngica. Para o fungo C. acutatum, o óleo essencial do indivíduo MYRO-180, de quimiotipo ácido nerólico + linalol, e seu composto majoritário apresentaram menores Concentração Mínima Inibitória (CMI) e Concentração Mínima Fungicida (CMF) de 0,03 e 0,1 µL.mL-1, respectivamente. Para o fungo P. destruens, o óleo essencial do indivíduo MYRO-159, de quimiotipo ácido nerólico, apresentou menor CMI de 0,05 µL.mL-1, e o quimiotipo ácido nerólico + linalol e seu composto majoritário apresentaram a menor CMF de 0,07 µL.mL-1. Para o fungo T. paradoxa,a combinação de citral + (E)-nerolidol destacou-se com CMI e CMF de 0,03 e 0,2 µL.mL-1, respectivamente. Linalol foi o menos tóxico sobre os três fungos testados.

Content and chemical composition of the essential oil of Lippia gracilis Schauer accessions in different drying times / Teor e composição química do óleo essencial de acessos de Lippia gracilis Schauer em diferentes tempos de secagem

Lippia gracilis, popularly known in Brazil as 'alecrim-de-tabuleiro', is used for many purposes, especially as antimicrobial and antiseptic. The drying process of aromatic and medicinal plants aims to minimize the loss of active principles and slow their deterioration, which may greatly influence the yield and chemical composition of some species. The objective of this study was to evaluate the effect of drying times (0, 2, 4, and 8 days) on the content and chemical composition of the essential oil of L. gracilis accessions LGRA-106, LGRA-109, and LGRA-201. The leaves were dried at 40 oC, and essential oil was extracted by hydrodistillation. Chemical analysis was performed by GC/MS. The experiment was carried out in a completely randomized design with three replications. The accessions of L. gracilis LGRA-106, LGRA-109, and LGRA-201 presented higher essential oil at four days of drying time. The accession LGRA-201 showed the highest essential oil yields at four and eight days of drying, with mean values of 0.038 and 0.029 mL g-1, respectively. The drying time did not influence the contents of thymol, methyl-thymol, γ-terpinene, and carvacrol in the essential oils of L. gracilis, but affected the contents of ß-caryophyllene, p-cymene, and carvacrol acetate. The essential oils of the three accessions analyzed in this study revealed different chemical profiles.

Lippia gracilis, conhecida popularmente como alecrim-de-tabuleiro é usada para muitos efeitos, especialmente como antimicrobiano e antisséptico. O processo de secagem das plantas aromáticas e medicinais visa minimizar a perda de princípios ativos e retardar a sua deterioração os mesmos podem afetar sobremaneira o rendimento e a composição química de algumas plantas. O objetivo deste trabalho foiavaliar o efeito de diferentes tempos de secagem (0, 2, 4 e 8 dias) no teor e na composição química do óleo essencial dos acessos LGRA-106, LGRA-109 e LGRA-201 de L. gracilis.As folhas foram secas a 40 oC e a extração do óleo essencial foi por hidrodestilação. A análise química foi feita através CG/EM. O ensaio foi implantado em delineamento inteiramente casualizado com três repetições. Os acessos de L. gracilis LGRA-106, LGRA- 109 e LGRA-201 apresentaram maiores rendimentos de óleo essencial no tempo de secagem de quatro dias. O acesso LGRA-201 apresentou os maiores teores de óleo essencial aos quatro e oito dias de secagem, com valores médios de 0,038 e 0,029 mL g-1, respectivamente. O tempo de secagem não influenciou os teores de timol, metil-timol, terpineno e carvacrol nos óleos essenciais de L. gracilis, porém afetou os teores de ß-cariofileno, ρ-cimeno, and acetato de carvacrol. Os óleos essenciais dos três acessos analisados apresentaram perfis químicos diferentes entre si.

Antimicrobial activity of Lippia gracilis essential oils on the plant pathogen Xanthomonas campestris pv. campestris and their effect on membrane integrity.

Xanthomonas campestris pv.campestris (Xcc) is the causative agent of black rot, a disease that causes serious damage to plants from Brassicaceae family. However, there are no chemicals or biological agent commercially registered for the control of this disease. Thus, this study aimed to evaluate the antimicrobial activity and chemical composition of Lippia gracilis essential oils (EOs) on Xcc aiming its use as effective biological control. We also investigated the effect of EOs on the integrity of the bacterial cytoplasmic membrane. Chemical analysis by GC/MS showed that the major compounds of the seven EOs of L. gracilis are thymol or carvacrol. The seven genotypes showed inhibition of bacterial growth with MIC from 700 µg.ml-1 to 1000 µg.ml-1, with the genotype LGRA-106 (rich in Thymol) with higher antimicrobial activity. The MIC for thymol and carvacrol were 250 µg.ml-1. After exposure to LGRA-106 EO (2×, 1×, 1/2×, 1/4×, and 1/8 x MIC for 5 min, it was observed a decreased cell viability and increased pI fluorescence, which indicates damage to the cytoplasmic cell membrane. This study demonstrates that L. gracilis EOs have antimicrobial activity and have a potential to be used in the control of black rot. Furthermore this antimicrobial activity is due, at least in part, to bacterial cytoplasmic membrane damage.

Germination temperatures affect the physiological quality of seeds of lettuce cultivars / Qualidade fisiológica de sementes de alface sob diferentes temperaturas na germinação

The objective of this study was to evaluate the physiological quality allied to biochemical quality of lettuce seeds by germination and enzymes expression at 20, 25, 30, 35, 40 and 42ºC. Germination speed index and percentage of germination were estimated. Isoenzyme expressions were assessed by alcohol dehydrogenase (ADH), malate dehydrogenase (MDH), catalase (CAT), esterase (EST), pyruvate decarboxylase (PDC) and glutamate oxaloacetate transferase (GOT). The experiment consisted of a completely randomized design in a factorial scheme 4x6, with four cultivars and six different temperatures, with four replications. The highest germination and vigor were observed for cv. 'Everglades' at 35°C, which proved that this cultivar is thermotolerant. Catalase can be considered a genetic marker for the identification ofthermotolerant lettuce cultivars. Cultivar 'Everglades' has potential to be used in lettuce breeding programs aimed at cultivars tolerant to high temperatures during germination.

O objetivo deste estudo foi avaliar a qualidade fisiológica e bioquímica de sementes de alface por meio da germinação e expressão de enzimas a 20, 25, 30, 35, 40 e 42ºC. As variáveis velocidade de germinação e o índice de velocidade de germinação foram estimadas. As expressões das enzimas alcool desidrogenase (ADH), malato desidrogenase (MDH), catalase (CAT), esterase (EST), piruvate descarboxilase (PDC) e glutamato oxaloacetato transferase (GOT) foram avaliadas. Para análise dos genótipos foi empregado o delineamento inteiramente casualizado em esquema fatorial 4x6, testando quatro cultivares e seis diferentes temperaturas, com quatro repetições. A maior germinação e vigor foram observadas para a cv. 'Everglades' a 35°C, o que prova que esta cultivar é termotolerante. A catalase pode ser considerada um marcador para a identificação de cultivares de alface termotolerantes. A cultivar 'Everglades' tem potential para uso em programas de melhoramento visando tolerância à alta temperatura durante a germinação.