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Strawberry is a food rich in bioactive compounds with great antioxidant potential. However, due to the high incidence of pests that affect crop cultivation, phytosanitary management still lacks control methods for agroecological cultivation. Thus, the present research aimed to evaluate the chemical composition and the potential of the essential oil of the leaves of Piper macedoi in the control of Cerosipha forbesi in laboratory and semi-field conditions. The concentration of essential oil in the leaves of P. macedoi that showed the highest mortality was 2.0 ml/L of oil, with a mortality above 91% under laboratory conditions. A mortality rate of 80% for all concentrations tested was observed after 24 h in all conditions tested. Thus, using essential oil from the leaf of P. macedoi can be a highly viable strategy in managing the aphid C. forbesi since it showed high mortality rates with small doses of oil.

Tomato is one of the most produced and consumed fruits in the world. However, it is a crop that faces several phytosanitary problems, such as fusarium wilt, caused by Fusarium oxysporum. Thus, this study aimed to evaluate citronella and melaleuca essential oils in vitro potential in the fungus F. oxysporum management. The chemical identification of the components in the essential oils was performed by gas chromatography with flame ionization and mass spectrometer detectors. The IC50 and IC90 were determined by linear regression and the percentage of inhibition of the fungus by analysis of variance. The major compounds in citronella essential oil were citronellal, Geraniol, and citronellol; in melaleuca (tea tree) oil were terpinen-4-ol and α-terpinene. Both oils promoted more significant inhibition at concentrations of 1.5 and 2.5 μL/mL, besides not presenting significant differences with commercial fungicides, confirming the high potential for using this control method in agriculture.

Two-spotted spider mite causes significant damage to various crops, often requiring synthetic acaricides for their control. However, the frequent use of these products causes several environmental problems. Thus, this work aimed to evaluate the acaricidal action, using the application by fumigation on female adults of

O gênero Capsicum pertence à família Solanaceae e possui grande diversidade evidenciada entre 38 espécies já catalogadas, todavia apenas cinco espécies são domesticadas, C. annuum, C. baccatum, C. pubescens, C. frutescens e C. Chinense. As pimentas possuem uma grande variabilidade fenotípica, principalmente em relação à coloração, forma e tamanho dos frutos, que pode ser analisada através de descritores morfoagronômicos, auxiliando nos estudos de diversidade genética da cultura. Objetivou-se com este estudo caracterizar com base em descritores morfoagronômicos e bromatológicos, 33 acessos de pimentas do banco de germoplasma do IFES Campus de Alegre e, com isso, estimar a divergência genética deles. Foram selecionados 22 descritores morfoagronômicas e 5 avaliações físico-químicas. Estimou-se a contribuição relativa das características através do método de Singh e a dissimilaridade genética entre os acessos empregando a distância de Mahalanobis e o método Unweighted Paired Group Methodusing Arithmetic Averages (UPGMA). O dendrograma de dissimilaridade foi composto por nove grupos e revelou que os acessos IFES58 e IFES78 são os que apresentam maior similaridade, enquanto os genótipos IFES58 e IFES96 foram os mais distantes geneticamente. As caracterizações morfoagronômica e físico-química foram eficientes para estimar a diversidade genética entre os 33 acessos de pimenta e destacar acessos com potencial para exploração em diferentes nichos de mercado para consumo in natura, processado ou para fins ornamentais. O estudo realizado evidencia a existência de alta variabilidade genética entre os acessos de Capsicum do banco de germoplasma do IFES Campus de Alegre.

The Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), is an internal primary pest of stored grains of great economic importance. Few insecticides registered for fumigation control for S. zeamais exist, which makes it necessary to search for more control alternatives. Thus, the objective of this work was to assess acute toxicity, sublethal effect, survival and behavioral response of the major components of essential oils, Thymol, Camphora, Terpineol, Canpheno, Eucalyptol, Limonene, β Pinene and Eugenol; and the mixtures of these components on S. zeamais. The results showed that the mixtures of the major components caused acute toxicity, reduced survival time and offspring production, in addition to altering the behavioral activity of S. zeamais. The mixture Camphor + Canphene presented a synergistic effect, with LC50 and LC90 of 2.77 and 20.34 µl/ml, respectively. The mixtures of the major components proved to be promising products for the control of S. zeamais.

O tomate (Solanum lycopersicum) pertence à família Solanaceae, sendo a segunda hortaliça mais cultivada a nível mundial. O banco ativo de germoplasma é fundamental para a conservação de recursos genéticos, as caracterizações morfológicas e bromatológicas desse banco são importantes para determinar: a dissimilaridade genética da cultura, indicar genótipos com aspectos relevantes para o melhoramento de plantas, identificação de duplicatas e entre outras. Objetivou-se caracterizar morfologicamente e bromatologicamente 34 acessos de tomate do banco ativo de germoplasma do IFES Campus de Alegre, e inferir a dissimilaridade genética entre eles. Foram selecionadas 20 variáveis morfoagronômicas, de acordo com os descritores internacionais, e 6 variáveis bromatológicas. No dendrograma de dissimilaridade genética utilizou-se o agrupamento de Ligação Média Entre Grupo (UPGMA) em combinação com o método de Tocher. Empregou-se o método de Singh para obter a contribuição dos caracteres. Os coeficientes de variação foram baixos e médios, o que está relacionado à confiabilidade dos dados obtidos. O diâmetro do fruto demonstrou maior herdabilidade e também a maior contribuição para a diversidade. O dendrograma de dissimilaridade genética foi constituído por nove grupos, onde os acessos dos grupos II e VI foram os mais recomendados para o consumo in natura, enquanto os acessos dos grupos VIII e IX foram os mais recomendados para o processamento, e os acessos do grupo V possuem dupla finalidade. As caracterizações foram primordiais para demonstrar a elevada variabilidade genética e também recomendar acessos com potenciais para atender diferentes nichos de mercado.

Two-spotted spider mite causes significant damage to various crops, often requiring synthetic acaricides for their control. However, the frequent use of these products causes several environmental problems. Thus, this work aimed to evaluate the acaricidal action, using the application by fumigation on female adults of Tetranychus urticae of essential oil from the leaves of Rosmarinus officinalis L., and its major compound, α-pinene. In addition, the essential oil was characterized by gas chromatography and mass spectrometry. α-pinene was the compound with the highest relative area in the oil (29.2%). In fumigation tests, α-pinene showed more significant toxicity than rosemary essential oil on two-spotted spider mite females with LC50 and LC90 values of 1.58 and 49.61 µL/L air, showing the impact of the chemical composition of the essential oil on the biological activity.

The use of agrochemicals has influenced the increase in agricultural productivity. However, the concern about damage to the human health and to the environment, resulting from the indiscriminate use of pesticides, has increased worldwide. Alternative methods for controlling pests and diseases have been proposed to maintain productivity and quality of life. A possibility is to use compounds produced by the secondary metabolism of plants, such as the essential oils. Some of these substances perform inhibitory or stimulatory activity on the development of other organisms. Plants from the genus Eucalyptus have been investigated and were chosen to be studied in the present work, due to the traditional knowledge regarding the potential of the essential oils from some species, as well as, for the need to use residues from their production. Therefore, were determined the yield, identified the compounds from the essential oils of E. urophylla and the hybrid E. urophylla x E. camaldulensis, and evaluated their biological activity through bioassays, investigating the phyto-cyto-genotoxicity and mutagenicity using Lactuca sativa and Sorghum bicolor as model plants. The essential oil from the hybrid provided a higher yield. Eucalyptol was the major compound identified for both oils, representing more than 85% of the compounds present. Both E. urophylla and the hybrid showed phyto-cyto-genotoxic, mutagenic effects, and clastogenic and aneugenic mechanisms of action, promoting epigenetic changes in the meristematic cells of L. sativa. The results point out to the bioherbicidal potential of these essential oils. El uso de agroquímicos ha influido en el aumento de la productividad agrícola. Sin embargo, la preocupación por los daños a la salud humana y al medio ambiente, resultantes del uso indiscriminado de plaguicidas, ha aumentado en todo el mundo. Se han propuesto métodos alternativos de control de plagas y enfermedades para mantener la productividad y la calidad de vida. Una posibilidad es utilizar compuestos producidos por el metabolismo secundario de las plantas, como los aceites esenciales. Algunas de estas sustancias ejercen una actividad inhibidora o estimulante del desarrollo en otros organismos. Se investigaron y seleccionaron plantas del género Eucalyptus para ser estudiadas en este trabajo, debido al conocimiento tradicional sobre el potencial de los aceites esenciales de algunas especies, así como a la necesidad de utilizar residuos de su producción. Por lo tanto, se determinaron los rendimientos, se identificaron los compuestos de los aceites esenciales de E. urophylla y el híbrido E. urophylla x E. camaldulensis, y se evaluó su actividad biológica mediante bioensayos, investigando la fitocitogenotoxicidad y mutagenicidad utilizando Lactuca sativa y Sorghum bicolor como planta modelo. El aceite esencial híbrido proporcionó el mayor rendimiento. El eucaliptol fue el principal compuesto identificado para ambos aceites, representando más del 85% de los compuestos presentes. Tanto E. urophylla como el híbrido mostraron efectos fitocitogenotóxicos, mutagénicos y mecanismos de acción clastogénicos y aneugénicos, promoviendo alteraciones epigenéticas en células meristemáticas de L. sativa. Los resultados apuntan al potencial bioherbicida de estos aceites esenciales. O uso de agroquímicos tem influenciado o aumento da produtividade agrícola. No entanto, a preocupação com os danos à saúde humana e ao meio ambiente, decorrentes do uso indiscriminado de agrotóxicos, tem aumentado em todo o mundo. Métodos alternativos de controle de pragas e doenças têm sido propostos para manter a produtividade e a qualidade de vida. Uma possibilidade é utilizar compostos produzidos pelo metabolismo secundário das plantas, como os óleos essenciais. Algumas dessas substâncias exercem atividade inibitória ou estimuladora do desenvolvimento de outros organismos. Plantas do gênero Eucalyptus foram investigadas e escolhidas para serem estudadas no presente trabalho, devido ao conhecimento tradicional quanto ao potencial dos óleos essenciais de algumas espécies, bem como, pela necessidade de aproveitamento de resíduos de sua produção. Portanto, foram determinados os rendimentos, identificados os compostos provenientes dos óleos essenciais de E. urophylla e do híbrido E. urophylla x E. camaldulensis, e avaliada sua atividade biológica através de bioensaios, investigando a fito-citogenotoxicidade e mutagenicidade utilizando Lactuca sativa e Sorghum bicolor como planta modelo. O óleo essencial do híbrido proporcionou maior rendimento. O eucaliptol foi o principal composto identificado para ambos os óleos, representando mais de 85% dos compostos presentes. Tanto E. urophylla quanto o híbrido apresentaram efeitos fito-citogenotóxicos, mutagênicos e mecanismos de ação clastogênicos e aneugênicos, promovendo alterações epigenéticas nas células meristemáticas de L. sativa. Os resultados apontam para o potencial bioherbicida desses óleos essenciais.

The world population growth has raised concerns about food security. Agricultural systems are asked to satisfy a growing demand for food with increasingly limited resources, and simultaneously still must reduce the impacts on the environment. This scenario encourages the search for safe and sustainable production strategies. Reducing losses in the production process can be one of the main ways to guarantee food safety. In fruticulture, it is estimated that more than 50% of the production can be lost between harvest and the final consumer due to postharvest diseases caused by phytopathogenic fungi. The fungi of the genus Colletotrichum are opportunistic and are associated with several diseases, being the anthracnose the most relevant in terms of the quality and yield losses in fruit species around worldwide. To control these diseases, the use of synthetic fungicides has been the main instrument utilized, however, because of their phytotoxicity to human health, the environment, and strong selection pressure imposed by continuous applications, the fungicides have caused resistance in the pathogen populations. So reducing the excessive application of these products is indispensable for human health and for sustainable Agriculture. Towards this purpose, research has been carried out to identify the phytopathological potentiality of essential oils (EOs) extracted from plants. Therefore, this review aims to contribute to the formation of knowledge bases, about the discoveries, recent advances, and the use of EOs as a strategy to alternatively control fungal disease caused by Colletotrichum spp. in postharvest fruits. Here, we provide valuable information exploring the application potential of essential oils as commercially useful biorational pesticides for food preservation, contributing to sustainable production and global food security.

The Barbados gooseberry crop has agricultural potential, but little information is available regarding cropping practices. More information on weed interference in Barbados gooseberry will support growers to take weed management decisions. The objective of this work was to study initial growth and development of Barbados gooseberry under the interference of weeds. The experiment was conducted in a completely randomized design, with five treatments, composed of Barbados gooseberry in competition with four weed species: slender amaranth (Amaranthus viridis), hairy beggarticks (Bidens pilosa), Benghal dayflower (Commelina benghalensis), purple nutsedge (Cyperus rotundus), and a weed-free control, with six replicates. Weed competition led to a decrease in growth and development of Barbados gooseberry reflected in a reduction of up to 40% in yield and 23% in protein content. Additional work must be conducted evaluating these findings under field conditions, using different seedling production and planting techniques potentially affecting these results.

Milk is among the food more consumed by humanity. In this way, a study of its physical-chemical characteristics is justified to analyze if its components are by the legislation and if its hygiene conditions, more precisely the use of formaldehyde as a preservative, are established. The International Agency for Research on Cancer warns that formaldehyde has physicochemical properties that make it carcinogenic when consumed in food. In Brazil, the legislation does not establish minimum values for the presence of formaldehyde in foods of animal origin, and the technique suggested by the Ministry of Agriculture, Livestock, and Supply is a qualitative test. With the large consumption of milk by the Brazilian population and because it is a food subject to adulteration. The present work sought to analyze milk in terms of its physical-chemical characteristics (fat, density, freezing point, non-greasy solids, lactose, and proteins) and develop a methodology to analyze formaldehyde derivatized with 2,4-dinitrophenylhydrazine in milk samples using gas chromatography coupled to mass spectrometer. La leche es uno de los alimentos más consumidos por la humanidad. De esta forma, se justifica un estudio de sus características físico-químicas para analizar si sus componentes están a la altura de la legislación y si están establecidas sus condiciones de higiene, más precisamente el uso de formaldehído como conservante. La Agencia Internacional para la Investigación del Cáncer advierte que el formaldehído tiene propiedades fisicoquímicas que lo hacen cancerígeno cuando se consume en los alimentos. En Brasil, la legislación no establece valores mínimos para la presencia de formaldehído en alimentos de origen animal, y la técnica sugerida por el Ministerio de Agricultura, Ganadería y Abastecimiento es una prueba cualitativa. Con el gran consumo de leche por parte de la población brasileña y por ser un alimento sujeto a adulteración. El presente trabajo buscó analizar la leche en cuanto a sus características físico-químicas (grasa, densidad, punto de congelación, sólidos no grasos, lactosa y proteínas) y desarrollar una metodología para analizar formaldehído derivatizado con 2,4-dinitrofenilhidrazina en muestras de leche, mediante cromatografía de gases acoplada a espectrómetro de masas. O leite está entre os alimentos mais consumidos pela humanidade. Dessa forma, justifica-se um estudo de suas características físico-químicas para analisar se seus componentes estão de acordo com a legislação e se suas condições de higiene, mais precisamente o uso de formaldeído como conservante. A Agência Internacional de Pesquisa sobre o Câncer alerta que o formaldeído possui propriedades físico-químicas que o tornam cancerígeno quando consumido em alimentos. No Brasil, a legislação não estabelece valores mínimos para a presença de formaldeído em alimentos de origem animal, e a técnica sugerida pelo Ministério da Agricultura, Pecuária e Abastecimento é um teste qualitativo. Com o grande consumo de leite pela população brasileira e por ser um alimento sujeito a adulteração; o presente trabalho buscou analisar o leite quanto às suas características físico-químicas (gordura, densidade, ponto de congelamento, sólidos não gordurosos, lactose e proteínas) e desenvolver uma metodologia para analisar formaldeído derivatizado com 2,4-dinitrofenilhidrazina em amostras de leite, usando cromatografia gasosa acoplada a espectrômetro de massa.

The objective of this work was to evaluate the acute toxicity, sublethal effect and behavioral alteration of L. serricorne exposed to the major components of essential oils, thymol, camphor, terpineol, camphene, eucalyptol, limonene, βpinene and eugenol. The adults of L. serricorne , aged 5 days, not sexed, were submitted to acute toxicity by fumigation, used fumigation chambers, 200 ml glass containers with 20 insects, subsequently the sublethal effect, longevity and behavioral response. The results show that the major components and mixtures caused acute toxicity, reduced the survival time and production of offspring and altered the behavioral activity of L. serricorne. The major components eucalyptol and terpineol presented 65% mortality, in which the mixtures terpineol + eucalyptol and camphor + thymol presented 47 and 52% over adults of L. serricorne. The mixture between terpineol + limonene allowed only 4% ofadults to L. serricorneemerge. Behavioral activity was altered by the eucalyptol + eugenol mixture. The results showed that the major components and mixtures are promising for the preparation and production of new insecticides. El objetivo deste trabajo fue evaluar la toxicidad aguda, el efecto subletal y la alteración del comportamiento de L. serricorne expuesto a los componentes principales de los aceites esenciales, timol, alcanfor, terpineol, canfeno, eucaliptol, limoneno, βpineno y eugenol. Los adultos de L. serricorne , de 5 días de edad, no sexados, fueron sometidos a toxicidad aguda por fumigación, utilizaron cámaras de fumigación, envases de vidrio de 200 ml con 20 insectos, posteriormente el efecto subletal, la longevidad y respuesta conductual Los resultados muestran que los principales componentes y mezclas causaron toxicidad aguda, redujeron el tiempo de supervivencia y la producción de descendencia y alteraron la actividad conductual de L. serricorne. Los componentes principales eucalyptol y terpineol presentaron un 65% de mortalidad, en el que las mezclas terpineol + eucalyptol y alcanfor + timol presentaron 47 y 52% sobre los adultos de L. serricorne. La mezcla entre terpineol + limoneno permitió que solo4% de los adultos de emergiera elL. serricorne. La actividad conductual fue alterada por la mezcla de eucaliptol + eugenol. Los resultados mostraron que los principales componentes y mezclas son prometedores para la preparación y producción de nuevos insecticidas. O objetivo deste trabalho foi avaliar a toxicidade aguda, efeito subletal e alteração comportamental de L. serricorne expostos aos componentes majoritários de óleos essenciais, timol, cânfora, terpineol, canfeno, eucaliptol, limonene, βpineno e eugenol. Os adultos de L. serricorne de idade de 5 dias não sexados foram submetidos à toxicidade aguda por fumigação, utilizou câmaras de fumigação, recipientes de vidro com 200 ml de capacidade com 20 insetos, posteriormente foi feito a avaliação do efeito subletal, longevidade e a resposta comportamental. Os resultados mostram que os componentes majoritários e as misturas causaram toxicidade aguda, reduziu o tempo de sobrevivência e produção de proles e alterou a atividade comportamental de L. serricorne. Os componentes majoritários eucaliptol e terpineol apresentaram 65% de mortalidade, na qual as misturas terpineol+eucaliptol e cânfora+timol apresentaram 47 e 52% sobre os adultos de L. serricorne. A mistura entre terpineol+limonene permitiu apenas 4% de emergência de adultos de L. serricorne. A atividade comportamental foi alterada pela mistura eucaliptol+eugenol. Os resultados evidenciaram que os componentes majoritários e as misturas são promissores para elaboração e produção de novos inseticidas.

Biodiesel is a fuel from vegetable oil or animal fat, and is a promising substitute for petroleum-derived diesel. Transesterification is the most widely used method in biodiesel production. Eggshell is rich in calcium carbonate (CaCO3), and when it is subjected to heat treatment it results in calcium oxide (CaO). CaO from eggshells was prepared at different calcination temperatures, and characterized by X-ray diffraction, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The obtained CaO was used as a catalyst. All catalysts showed good stability and excellent morphology for biodiesel synthesis. Catalytic activity was evaluated by the methyl transesterification reaction of cotton oil for 3 h, 9:1 methanol:oil molar ratio, 3 wt% (catalyst/oil weight ratio) catalyst and 60°C. Biodiesels showed an ester content of 97.83%, 97.23% and 98.08%, obtained from calcined eggshell at 800°C, 900°C and 1000°C, respectively. Biodiesel quality was affected by the acidity of the cation exchange resin. The kinematic viscosity of biodiesel was in accordance with specification, except for the biodiesel obtained from the calcined catalyst at 1000°C. The CaO from eggshells obtained at different calcination temperatures is promising for biodiesel synthesis.

Leaf essential oils of guava (Psidium guajava L., Myrtaceae) show intraspecific variation in chemical composition. The essential oils of 21 P. guajava genotypes, obtained in each season in 2015 and 2016, were analyzed via GC-FID and GC–MS to detect composition variability due to seasonal fluctuation and a total of 35 compounds were identified. Qualitative and semi-quantitative variations were observed in different genotypes and within same genotypes during different seasons. Overall, the genotypes showed a predominance of sesquiterpenes with a relative area > 70%. Spring was the most varied season, revealing a decrease in hydrogenated sesquiterpenes and an increase of oxygenates. Precipitation data and daily temperatures during the experiment were registered at the time of guava leaf sampling to verify whether this phenomenon was due to a seasonal condition. We found that climatic variations were not the primary influence on this result. Phenological factors like as flowering showed a decrease in compounds like (E)-Caryophyllene and α-Humulene in the essential oils of all studied genotypes and were determined to be influenced by that cyclic phenomenon. Hence, due to the variations that occur in the chemical compounds the harvesting of leaves for the extraction of essential oils should be performed according to the highest concentrations of the active principles.

The mosquito Aedes aegypti L. is one of the largest vectors of human pathogens, including the dengue and chikungunya viruses. However, its control is challenging. Synthetic insecticides are one of the most used methods of vector control, but their use raises a series of environmental issues. Therefore, the application of natural products constitutes an alternative practice, as they can be effective, easily biodegradable and inexpensive. The essential oil obtained from leaves of guava ( Psidium guajava L.) has shown promising larvicidal activity against A. aegypti . However, the existence of different essential oil chemotypes in this species makes it necessary to study the influence of such variation on the larvicidal activity. In the present work, the essential oils from the guava cultivars SEC, C4, C6, PAL and PET were evaluated for larvicidal effect on A. aegypti . The oils were found to be efficient, with LC 50 ranging from 39.48 to 64.25 μg mL −1 . SEC was the most promising cultivar, with lowest LC 50 and one of the highest extraction yields among the cultivars (0.35%). The chromatographic profile of the essential oils evidenced mainly sesquiterpenes; hence, this group of compounds may be responsible for the larvicidal effect. Besides constituting a larvicide alternative, the use of essential oils could also create new income sources for guava producers, since a large amount of plant matter is generated as a result of successive prunings.

Red Mud (RM) based gold catalysts were prepared by supporting gold nanoparticles (AuNPs) on the RM residue reduced either with H2 or with ethanol – which promoted partial coating of the RM with carbon. The materials were characterized by X-ray diffraction, Mossbauer spectroscopy, elemental analysis CHN, transmission electron microscopy and EDS microanalysis. Their catalytic performance was evaluated in the liquid-phase oxidation of benzyl alcohol by molecular oxygen, for the first time, as far as we know. The results showed that AuNPs with diameters of around 10 nm were successfully supported and distributed on the surface of red mud based materials. Furthermore, carbon coating allowed better incorporation of AuNPs on the material surface and better dispersion of the material into the reaction solutions. AuNPs supported on RM reduced in ethanol and, therefore, coated with carbon showed better catalytic performance than AuNPs supported on MR reduced in hydrogen.

β-Citronellol and geraniol are bio-renewable compounds found in essential oils of various plants. Allylic oxidation of trisubstituted sterically highly encumbered carbon-carbon double bonds in their molecules with dioxygen can be efficiently catalyzed by the palladium acetate/p-benzoquinone combination under 5−10 atm of dioxygen pressure without the need for conventionally used metal co-catalysts. Both substrates gave allyl acetates in ca. 90% combined yield. The oxidation of geraniol proceeded with excellent site-selectivity involving only one of its two C C bonds. Geraniol gave both linear and branched allyl acetates in comparable yields, whereas the reaction of β-citronellol showed high regioselectivity for the corresponding branched product. Polyfunctionalized oxygenated terpenes produced from β-citronellol and geraniol are of a potential importance as ingredients for fragrance compositions.

Linalool and nerol, bio-renewable terpenic alkenyl alcohols found in many essential oils, were selectively oxidized by molecular oxygen in the presence of the chloride-free Pd(OAc) 2 / p -benzoquinone catalytic system. An efficient dioxygen-coupled catalytic turnover was achieved in the absence of auxiliary electron-transfer mediators under 5–10 atm of oxygen pressure. In both substrates, only one of two olefinic bonds was involved in the interaction with palladium, whereas the other one remained intact. Primary allylic acetates were formed as major reaction products: 8-linalyl acetate and 8-neryl acetate from linalool and nerol, respectively. In the case of linalool, the intramolecular cyclization product (known as herboxide), also resulted from the oxidation of the internal double bond, was also formed in significant amounts. All monoterpenic compounds obtained in the present work are natural products found in exotic plants or grape wines and are potentially useful as fragrance ingredients due to their pleasant scents.

α-Bisabolol, a sesquiterpene found in various essential oils, has numerous direct commercial uses in cosmetic and therapeutic formulations. In the present work, we report two novel liquid-phase processes for the catalytic oxidation of α-bisabolol with dioxygen, in which palladium salts (PdCl 2 or Pd(OAc) 2 ) are employed as sole catalysts. The addition of co-catalysts conventionally used for the re-oxidation of reduced palladium species or special ligands for their stabilization is not required. The reactions occur in non-acidic solvents, i.e., aqueous methanol or dimethylacetamide, and give exclusively the products derived from the interaction of the acyclic olefinic bond with palladium, whereas the other olefinic bond remains intact. The method allows to perform the green and simple synthesis of poly-functionalized compounds potentially useful for fine chemical industry as fragrance ingredients and synthetic intermediates, starting from a bio-renewable substrate.

This study was designed to evaluate the feasibility of using oils extracted from seeds of soursop industrial waste for use as pharmaceutical ingredients. For that, soursop seeds were subjected to different processes of extraction of fixed oil, by chemical and mechanical routes. After characterization of fixed oils, the feasibility of using them as pharmaceutical excipients was explored by preparing creams in which the oils were used as emollient and/or antioxidant excipient. The oil extracted from soursop seeds in a Soxhlet device and ethyl ether solvent (SFO) showed a yield of 30.72 ± 0.09 % (w w−1) and, in a domestic extruder (MFO), 23.86 ± 0.78 % (w w−1). These oils showed physicochemical attributes that indicative of good preservation. The major fatty acid was the oleic acid, with 42.94–43.73 % in relative area, followed by linoleic with 29.5%–30% in relative area. In the non-grease fraction, the SFO showed considerable levels of phenolics (194.5 ± 31.1 mg kg−1) and tocopherols (608.2 ± 36.7 mg kg−1), which gave it an antioxidant potential, confirmed by the 2,2-diphenyl-1-picrylhydrazyl test, with a concentration effective for 50% inhibition (IC50) of 2.8 mg mL−1. Finally, the evaluation of the quality parameters of the creams, suggests that the use of fixed soursop oils to replace the synthetic ingredients usually incorporated (decyl oleate, liquid petrolatum and butylhydroxytoluene), originated formulations with adequate physical and chemical stability. These findings suggest that both oils obtained are possible candidates for use as emollients and antioxidant in pharmaceutical formulas. In addition, contributing to minimize the generation of waste from the fruit agribusiness and add economic value to a by-product generated in the production of fruit pulp.

Botanical insecticides based on oils and plant extracts have proven to be an efficient alternative method for pest control, as required by agroecological systems. Tephrosia vogelii (Hook.f.) has been used in agriculture as a source of green manure and in the control of pests and diseases. However, there are few studies regarding the use of compounds derived from the secondary metabolism of this plant. Chemical compounds present in the essential oil of Tephrosia vogelii flowers were identified, aiming at its use to control the aphid Cerosipha forbesi in the strawberry crop. Bioassays were carried out under laboratory and semi-field conditions, with different concentrations of the essential oil and the lethal concentrations LC50 and LC90 were estimated. Only two groups of terpenic compounds were identified in the essential oil of T. vogelii: monoterpenic hydrocarbons (alpha-pinene; limonene and ocimene) and oxygenated sesquiterpenes (nerolidol, spathulenol and farnesol). The essential oil of T. vogelii presented toxic effect against C. forbesi, with the LC50 and LC90 of the insect population estimated at 0.106 and 0.380 mL/L, respectively. Under semi-field conditions, mortality increased at higher concentrations, and the LC50 and LC90 were estimated at 0.114 mL/L and 0.465 mL/L, respectively. Mortality over 90% was observed after 24 h of the essential oil application, for all of the tested concentrations, showing an insecticidal action of the oil against the aphid C. forbesi.

A novel selective palladium catalyzed oxidation of α-bisabolol by molecular oxygen under chloride-free nonacidic conditions has been developed. α-Bisabolol is a sesquiterpenic alcohol available from essential oils of various plants. The reaction proceeds in aqueous methanol solutions over the Pd(OAc)2/Cu(OAc)2 catalytic system and gives exclusively the products resulting from the interaction of palladium with a sterically encumbered internal acyclic double bond. No concomitant oxidation of the second double bond, the endocyclic one, occurs. Novel poly-functionalized sesquiterpenoid compounds obtained at the oxidation of α-bisabolol are potentially interesting for cosmetic, fragrance and pharmaceutical applications.

Semisynthetic phenol derivatives were obtained from the natural phenols: thymol, carvacrol, eugenol, and guaiacol through catalytic oxychlorination, Williamson synthesis, and aromatic Claisen rearrangement. The compounds characterization was carried out by 1H NMR, 13C NMR, and mass spectrometry. The natural phenols and their semisynthetic derivatives were tested for their antimicrobial activity against the bacteria: Staphylococcus aureus, Escherichia coli, Listeria innocua, Pseudomonas aeruginosa, Salmonella enterica Typhimurium, Salmonella enterica ssp. enterica, and Bacillus cereus. Minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were determined using concentrations from 220 to 3.44 μg mL–1. Most of the tested compounds presented MIC values ≤220 μg mL–1 for all the bacteria used in the assays. The molecular properties of the compounds were computed with the PM6 method. Through principle components analysis, the natural phenols and their semisynthetic derivative...

The essential oil of Psidium guajava L. has been studied for pharmacological and industrial purposes, without considering the plant's genotype regarding the heterogeneity of its composition. The present study aimed to characterize the chemotype diversity of the essential oil extracted from the leaves of 22 genotypes of P. guajava grown in two different environments in the state of Espirito Santo, Brazil, and to identify the different chemical markers present in these plants. Essential oil from the leaves of the P. guajava genotypes was extracted by hydrodistillation, and its chemical composition was analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Thirty-three compounds were identified, comprising 87.5-99.0% of the total composition, with a prevalence of sesquiterpenes in all samples. The major compounds identified consisted of (E)-trans-Caryophyllene, α-Humulene, trans-Nerolidol, β-Bisabolene, β-Bisabolol, and Hinesol, the first of which was identified as a possible chemical marker for the species. Multivariate factor analysis of the chemical composition of P. guajava oil identified three chemotypes: Commercial - PAL, SEC, PS, PET, C7, C11, and C17MI, characterized by high levels of β-Selinene, α-Selinene, Hinesol, and 14-hydroxy-epi-(E)-caryophyllene, with β-Selinene and α-Selinene as the chemical markers; C10 and C13, exhibiting high levels of Elemol, trans-Nerolidol, trans-β-Eudesmol, and (2Z, 6Z)-Farnesol, which were indicated as chemical markers, and Cortibel - C1, C2, C3, C4, C5, C6, C8, C9, C12, C14, C15, C16, C17LI, which retained high levels of α-Cedrene, cis-α-Bergamotene, α-Humulene, Humulene epoxide, epi-α-Cadinol, β-Bisabolol, and α-Bisabolol, with β-Bisabolol and α-Bisabolol as the chemical markers. The use of guava genotypes with different chemotypes, that are agronomically favorable to fruit production and essential oil exploitation adds value to the crop and renders it more sustainable. Given guava crops produce large amounts of leaf biomass, resulting from successive prunings, the extraction of their essential oil, which retains commercially valuable compounds, can be feasible.

Uma vez que as plantas medicinais são identificadas e utilizadas em função de seus constituintes químicos, objetivou-se com este estudo, quantificar os teores de fenólicos totais, flavonóis totais e antocianinas presentes na espécie vegetal Murraya paniculata (L.) Jack (murta), correlacionando os teores encontrados nas partes da planta com duas diferentes estações do ano (verão e inverno). As folhas de murta foram coletadas no município de Alegre - ES, dividindo em partes (ápice, mediano e basal), obedecendo às estações verão/inverno. No verão, observaram-se os maiores teores de metabólicos nos ramos medianos, e basal da planta, com exceção dos fenólicos totais que apresentaram os maiores teores no inverno. Com os resultados encontrados, conclui–se que existe uma diferença significativa entre partes da planta e época, e tais resultados estimulam a continuação de estudos com esta espécie.

The palladium/p-benzoquinone catalyzed aerobic oxidation of α-bisabolol, a bio-renewable substrate with strong therapeutic potential available from various essential oils, has been developed. The reaction gives three main products arising from the oxidation of the sterically encumbered trisubstituted double bonds of the substrate, either endocyclic or exocyclic or both. Novel poly-functionalized sesquiterpenoids obtained with high combined selectivity from the oxidation of α-bisabolol are potentially useful as components of synthetic perfumes, cosmetics and pharmaceuticals. The system promotes an efficient dioxygen-coupled catalytic turnover in the absence of auxiliary redox-active co-catalysts under superatmospheric oxygen pressure. Alternatively, the reaction can be performed at atmospheric pressure in the presence of catalytic amounts of copper acetate as an electron transfer mediator for the regeneration of BQ during the catalytic cycle.

The large amount of biomass resulting of successive prunings in guava crop, can add value to the culture by the extraction of their essential oil, which possess compounds of commercial value. For the first time, the stability of the essential oil from Psidium guajava L. was studied in field experiments considering the effects of 22 guava genotypes and two environments. The essential oils from leaves of adult plants, cultivated in experimental design, were characterized via FID-GC–MS analysis and sixteen volatile substances were identified as major compounds. The environments exerted influence in the essential oil profiles from guava, being more expressive in some genotypes (C7, C13 and C17) and more stable in others (C1, C5, C16 and PET). In addition, the oil composition varied among genotypes. The genotypes C10, C13 and SEC showed high levels of (E)-trans-Caryophyllene; C3 and C6 of alpha-Humulene; and C2, C8, C12, C15 and C16 of beta-Bisabolol. These compounds had little influence of environmental and as have biological activity proven, which makes it feasible to use these genotypes in breeding programs, in selection and crossing approaches.

Isoeugenol [2-methoxy-4-(prop-1-en-1-yl)phenol; compound 1] can be oxidized to vanillin (4-hydroxy-3-methoxybenzaldehyde, compound 2) by H2O2 in the presence of the n-Bu4NVO3/pyrazine-2-carboxylic acid catalytic combination. A 50% yield of 2 was attained in a 2-h reaction at 80 °C, with a turnover number being higher than 1200. Kinetics of the transformation of 1 into 2 have been studied. The results obtained indicate that the first step of the 1 activation is its interaction with a hydroxyl radical. Further transformations of the primary product formed in this step proceed via several routes, one of which leads to the formation of 2. It has been proposed that the interaction of vanadate with the first molecule of H2O2 gives a V(IV)-containing species and hydroperoxyl radical: “VV–OOH” → “VIV” + HOO . In the next step, the V(IV) complex reacts with the second molecule of H2O2 affording a hydroxyl radical and recovering a starting V(V)-containing species: “VIV” + H2O2 → “VV” + HO− + HO . Then, the hydroxyl radical attacks a double bond in the substrate: HO + CHR′ CHR″ → C HR′–CH(OH)R″. The carbon-centered radical formed in the latter step can rapidly capture a molecule of O2 from the atmosphere: C HR′–CH(OH)R″ + O2 → C(OO )HR′–CH(OH)R″. Finally, a rupture of the C C bond gives rise to the formation of aldehyde 2.

Cobalt–iron magnetic composites prepared by the thermal treatment of an iron oxide-rich soil in the presence of sucrose and cobalt(II) sulfate are efficient heterogeneous catalysts for the liquid-phase aerobic oxidation of thiols into disulfides. The materials have been characterized by Mossbauer spectroscopy, XRD, N 2 adsorption–desorption, and elemental analysis. It has been shown that the isomorphic substitution of iron by cobalt occurs preferentially in the framework of the wustite (FeO) phase and strongly affects the catalytic behavior of the material. The choice of a solvent is critically important for the efficiency of the reaction. In weakly basic solvents, such as dimethylformamide and dimethylacetamide, disulfides can be obtained in near-quantitative yields at low catalyst loading (0.008 mol%). A significant practical advantage of this environment-friendly process is the use of inexpensive magnetically recoverable materials as catalysts and oxygen as a final oxidant as well as mild alkali free conditions. Of particular note are the stability of the catalyst toward leaching and the possibility of catalyst recycling without any special treatment.

A palladium-catalyzed, aerobic oxidation of naturally occurring allylbenzenes, i.e., eugenol, methyleugenol, safrole, and estragole, in dimethyl-acetamide/water solutions under mild conditions has been developed, in which palladium(II) chloride is used in the absence of co-catalysts or special stabilizing ligands as the sole and recyclable catalyst. Methyl ketones that are important for the flavour and pharmaceutical industries have been obtained in good to excellent yields with low catalyst loadings (1―2 mol%) and high average turnover frequencies. This simple catalytic method represents an ecologically benign and economically attractive route to industrially valuable compounds starting from renewable substrates easily available from essential oils.

Nuclear oxybromination of unprotected aromatic primary amines catalyzed by copper(II) acetate [Cu(OAc)2] under mild conditions has been developed, in which bromide ions are used as halogenating agents and dioxygen as a final oxidant. The catalyst shows not only high regioselectivity for para- or ortho-isomers but also a remarkable chemoselectivity for monobromination. Oxychlorination of aniline can also be performed under similar conditions, albeit with lower selectivities, with N-phenylacetamide being the main by-product. This simple catalytic method represents ecologically benign and economically attractive synthetic pathway to expensive low-volume aromatic haloamines.

Cobalt- and manganese-substituted ferrites were used as heterogeneous catalysts for liquid-phase aerobic oxidation of various monoterpenic alkenes . The materials were prepared by co-precipitation and characterized by Mossbauer spectroscopy, powder X-ray diffractometry, magnetization measurements, and elemental analysis. The results show that isomorphic substitution of iron in the ferrite crystalline structure occurred preferentially at octahedral positions and strongly affected its catalytic properties in the oxidation of monoterpenes . Various valuable oxygenated monoterpenic compounds were obtained with high combined selectivities (75–95%) at ca. 40% substrate conversions. Oxidations of β-pinene and 3-carene led almost exclusively to allylic mono-oxygenated derivatives, whereas limonene and α-pinene gave both epoxides and allylic products. The use of inexpensive catalyst and oxidant, solvent-free conditions, and high final product concentrations (ca. 40 wt%) are significant practical advantages of this environmentally friendly process. The catalysts undergo no metal leaching and can be easily recovered by the application of an external magnet and reused.

A simple, low cost and highly selective method for the synthesis of mono-bromophenols from phenol and electron-rich phenolic compounds has been developed. Bromide ions are used as halogenating agents, dioxygen as a final oxidant, and Cu(OAc) 2 as a catalyst.