Eugenol is the major component of clove essential oil and has demonstrated relevant biological potential with well-known antimicrobial and antioxidant action. Therefore, this work carried out the synthesis, purification, characterization, and evaluation of the antioxidant and antibacterial potential of 19 eugenol derivatives. The derivatives were produced by esterification reactions in the hydroxyl group (−OH) of eugenol with different carboxylic acids and also by addition reactions in the double bond of the allyl group. The derivatives had a promising antibacterial potential, including a lower minimum inhibitory concentration of 500 μg/mL than eugenol (1000 μg/mL). In addition, the derivatives were active against bacterial strains (Escherichia coli, Staphylococcus aureus) that eugenol itself showed no activity, thus increasing the spectrum of antibacterial action. As for the antioxidant activity, it was observed that the derivatives that involved esterification reactions in the hydroxyl group (−OH) of the eugenol molecule’s phenol resulted in a significant reduction of the antioxidant action (IC50 > 100 μg/mL) when compared with the eugenol precursor molecule (IC50 = 4.38 μg/mL). On the other hand, the structural changes located in the double bond affected much more smoothly the capacity of capturing radicals than the starting molecule, also being obtained derivatives with proximal antioxidant capacity (IC50 = 19.30 μg/mL) to commercial standards such as Trolox (IC50 = 16.00 μg/mL).Electronic supplementary materialThe online version of this article (10.1186/s13065-018-0407-4) contains supplementary material, which is available to authorized users.

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RESUMOAs antocianinas compõem uma classe de metabólitos secundários no qual, inúmeras vezes, é associado com a coloração de espécies vegetais. Esse grupo encontra-se presente em diversas partes da planta, tais como: caule, flor, fruto, folha, entre outros. Com isso, o presente trabalho tem como objetivo a quantificação de antocianinas dos extratos em etanol-água das diversos partes (Galhos, Caule, Raiz e Flores), da Embiratanha (Pseudobombax marginatum). Foram avaliados os extratos com o intuito de estimar a concentração de antocianinas presente nos mesmos. Dentre as partes supracitadas, o Caule da embiratanha apresentou a maior concentração de antocianinas de 0,49/100g do material. O trabalho foi de grande importância para a quantificação de antocianinas da Pseudobombax marginatum, uma planta com fins terapêuticos amplamente utilizada na medicina popular. PALAVRAS-CHAVE: embiratanha, quantificação de antocianinas, metabólitos secundários. QUANTIFICATION OF ANTHOCYANINS OF EMBIRATANHA (Pseudobombax marginatum) ABSTRACTAnthocyanins is a class of secondary metabolites which often is associated with plant species colors. This group is present in various parts of the plant such as stem, flower, fruit, leaf, among others. In this work, the extracts anthocyanin contents were evaluated in ethanol-water members (Branches, Stem, Root and Flower) of the Embiratanha -Pseudobombax marginatum. Extracts were evaluated in order to estimate the anthocyanins concentrations present in the same. Among the members, the embiratanha's Stem showed the highest anthocyanins content of 0.49 / 100g of material. This study was of great importance for the quantification of Pseudobombax marginatum, a widely used plant for therapeutic purposes.

RESUMO PROFILE AND EXPECTATION OF THE STUDENTS CONCLUDING OF THE COURSE TECHNICIAN OF IFRN, CAMPUS APODI ABSTRACTThis study aims to characterize the profile and expectations of students in third and fourth years of integrated technical courses in Animal Science and biofuels, from Federal Institute of Education, Science and Technology of Rio Grande do Norte -Campus Apodi. The survey was conducted with 138 students, through the use of questionnaires with open and closed questions. Data analysis was performed descriptively and presented in percentage. The main results showed that women are the majority (60.9%) and the average age was 17.4 years. 99.3% of students said they want to attend college and the Federal University of Rio Grande do Norte was mentioned institution. The courses most frequently cited by students were: Medicine, Science and Technology, Chemical Engineering, Civil Engineering, Law and Veterinary Medicine. As a professional practice, 89.9% of students performing in the form of research projects or extension and 10.1% in the form of internships. Over 97% of students are satisfied with the disciplines, but 64.5% are not satisfied with the amount of practical classes of the courses. As for the labor market, 58.8% believe that there are good opportunities. Thus, are necessary measures to qualify the student teaching, however, depend on the same of a democratic management to consider the opinion of the whole school community.

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RESUMOAs plantas medicinais têm ampla gama de aplicações, devido às suas potenciais atividades biológicas, com um ou mais princípios ativos relevantes para a saúde humana. Este fato torna-se preocupante a partir do momento que há um aumento crescente na comercialização das mesmas, pois, determinados tipos de ervas, de composições químicas e propriedades farmacológica diferentes são muitas vezes comercializados com nomes populares idênticos, como é o caso do alecrim, que designa várias espécies de plantas medicinais. Portanto, este estudo teve como objetivo realizar a extração e análise comparativa da composição química do óleo essencial de uma amostra comercial, que não descreve sua identificação botânica e uma amostra in natura, sendo ambas reconhecidas pelo nome de alecrim. Foram observadas diferenças significativas entre a composição química das amostras, confirmando a importância de um maior detalhamento quanto a sua classificação botânica e constituição química na descrição das plantas medicinais comercializadas e utilizadas pela população, a fim de evitar a utilização indevida desta fonte natural, uma vez que as propriedades farmacológicas atribuidas a cada espécie estão intimimamente relacionada com a sua composição química. PALAVRAS-CHAVE: Lippia sidoides, Rosmarinus officinalis, óleo essencial e Alecrim COMPARATIVE ANALYSIS OF THE CHEMICAL COMPOSITION OF VOLATILE SAMPLES OF ROSEMARY IN NATURE WITH COMMERCIALLY AVAILABLE ABSTRACTMedicinal plants have a wide range of applications due to their potential biological activities, with many active principles that are relevant to human health. This is a fact that has been becoming of concern due to the increasing in the commercialization of such plants, since certain types of herbs, of different chemical compositions and pharmacological properties are often marketed with identical popular names. We can cite rosemary, which designate several species of medicinal plants. Therefore, this study aimed to perform an extraction followed by a comparative analysis between the chemical composition of the essential oil present in a commercial sample (with a non-specified botanical identification) and a sample in nature, both recognized as being rosemary. Significant differences between the chemical composition of the samples were observed, confirming the significance of providing further details as to its botanical classification and chemical constitution, when describing medicinal plants commercialized and used by the population. This is especially important to avoid misuse of this natural source, since the pharmacological properties attributed to each species are closely related to its chemical composition.

Acetylcholine deficiency is a neurochemical characteristic of patients with clinical diagnosis of Alzheimer´s disease. Substances that inhibit the enzyme acetylcholinesterase, increasing levels of acetylcholine in the brain, are a promising form of treatment. Studies relate the use of omega-3 fatty acids in the treatment and prevention of Alzheimer's disease. The Northeast Region of Brazil has an enormous biological diversity and a wide variety of fish species. In this work, the oils of eleven species of marine fish found on the coast of Ceará, Brazil, were analyzed in relation to the fatty acid profile and the inhibitory activity of the enzyme acetylcholinesterase. Total lipids were extracted from fish samples by Folch metodology. The lipid extracts of the fish and industrialized fish oil, used for comparison, were esterified and fatty acid profiles were analyzed. The acetylcholinesterase inhibitory activity was measured quantitatively. The oils presented a high percentage of saturated fatty acids, which is a general characteristic of tropical fish. Oleic acid was the highest monounsaturated fatty acid. Oils of Scomberomorus cavalla, Lutjanus synagris and Haemulon plumieri presented expressive percentages of polyunsaturated fatty acids and the most potent anticholinesterase activities. This research showed the oils of S. cavalla, L. synagris and H. plumieri may be promising functional food products of active fatty acids as new therapies to treatment or prevention of Alzheimer's disease. The expressive concentration of unsaturated and polyunsaturated fatty acids together with their relevant anticholinesterase activity are characteristics of the importance of these fish oils.

Use of natural medicine has been used by man since time immemorial, and this use has grown considerably in recent times. Thus, this study aims to make a comparator analysis regarding the phytochemical test, antioxidant activity and total phenolic content of the extracts of the leaves in ethanol and their respective fractions of Citrus limonium (lemon) and Capsicum frutescens L. (chilli pepper). To compare them was observed that ethanol extract of both plants showed the better antioxidant activity, Capsicum frutescens L. with 204.60 ppm and 99.07 ppm with Citrus limonium. With regard to the phenolic content of the hexane extract and lemon extract in ethanol pepper were those that showed a higher content. Overall, it was noted that Citrus limonium excelled both in relation to their antioxidant activity and the phenolic content. KEYWORDS:Citrus limonium, Capsicum frutescens L., Phytochemical test, Antioxidant activity, Total phenols. CONTRIBUIÇÃO AO ESTUDO FITOQUÍMICO E TESTES QUÍMICOS DOS EXTRATOS DE Citrus limonium (LIMÃO) e