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The brown dog tick, Rhipicephalus sanguineus, is one of the principal tick species of medical-veterinary interest because of its large capacity for transmitting pathogens. This study sought to evaluate the potential for inhibition of acetylcholinesterase and the repellent activity of volatile oils of Satureja montana L., Lamiaceae; Myristica fragrans Houtt., Myristicaceae; and Cymbopogon flexuosus (Nees ex Steud.) W.Watson, Poaceae. The inhibition of AChE was evaluated by spectrophotometry, and the repellent effect was determined by a test of choice in assays with unfed R. sanguineus adults. The principal components found were borneol, γ-terpineol, carvacrol, and p-cymene in the oils of S. montana; sabinene, α-pinene, and β-pinene in the volatile oil of M. fragrans; and geranial in C. flexuosus. The greatest inhibition of acetylcholinesterase was observed with the oils of S. montana and M. fragrans, with an average inhibitory concentration (IC50) of 0.024 and 0.023 µg/ml, respectively. The greatest repellent action against the tick was observed for the oil of S. montana, which exhibited a percentage of repellency (%R) greater than 80% at 14 µl/ml. This activity remained effective for up to 3 h at the highest concentration tested (56 µl/ml), with a %R higher than 60% at these conditions.

In addition to pesticidal activity, the capacity of natural compounds to inhibit the reproduction of parasites emerge as an important alternative tick control method. In this context, Satureja spp. stand out due to their recognized pesticidal properties. Among parasites of veterinary importance, the cattle tick, Rhipicephalus microplus, is responsible for great economic losses in livestock and transmission of relevant pathogens. Thus, the aim of this study was to evaluate the effects of different concentrations of the essential oil of Satureja montana L. on the ovary morphology of R. microplus engorged females through histological and histochemical techniques. The most remarkable morphological changes found were: cytoplasmic vacuolation of germ cells, irregular and thicker chorion, irregular oocyte shape, ring-shaped nucleolus, decrease in protein and carbohydrate content in oocytes, in addition to cellular changes in the oviduct and pedicel. All morphological changes were assessed using a semiquantitative method already established in the literature. Ticks exposed to 5.0 μl/ml of essential oil showed the most significant changes when compared to control groups. Thus, the essential oil of S. montana L. damaged the reproductive system of R. microplus, which may impair ticks' offspring production and promote a long-term control of this species. HIGHLIGHTS: The essential oil of Satureja montana L. affects the ovary morphology of the cattle tick. The main morphological alterations found were cytoplasmic vacuolation, irregular and thicker chorion and irregular oocyte shape. These alterations may impair the development of eggs.

Essential oils can be a useful alternative to the use of synthetic fungicides because they have biological potential and are relatively safe for food and agricultural products. The objectives of the present study were to evaluate the antifungal and antimycotoxigenic activities of the essential oils from Satureja montana L., Myristica fragrans H. and Cymbopogon flexuosus S. against Aspergillus flavus and Aspergillus ochraceus, as well as their effects on ergosterol synthesis and membrane morphology. The antifungal potential was evaluated by mycelial growth analysis and scanning electron microscopy. Fungicidal effects against A. flavus, with MFC of 0.98, 15.62 and 0.98 µL/mL, respectively, were observed for the essential oils from S. montana, M. fragrans and C. flexuosus. Aspergillus ochraceus did not grow in the presence of concentrations of 3.91, 15.62 and 0.98 µL/mL of the essential oils from S. montana, M. fragrans and C. flexuosus, respectively. The essential oils significantly inhibited the production of ochratoxin A by the fungus A. ochraceus. The essential oils also inhibited the production of aflatoxin B1 and aflatoxin B2. The biosynthesis of ergosterol was inhibited by the applied treatments. Biological activity in the fungal cell membrane was observed in the presence of essential oils, given that deleterious effects on the morphologies of the fungi were detected. The essential oils under study are promising as food preservatives because they significantly inhibit toxigenic fungi that contaminate food. In addition, the essential oils hindered the biosynthesis of mycotoxins.

The present work sought to characterize the cyanogenic glycoside dhurrin in five sugarcane varieties and to determine its possible relationship with the formation of ethyl carbamate in cachaca. For each variety, methanol, ethyl acetate and hexane extracts were prepared and submitted to thin layer chromatography. Chromatographic spots were revealed with iodine vapors. The physical and chemical parameters of the spirits produced from the five different varieties of sugar cane and by different production processes were within the legal limits. Although not exceeding the limit for ethyl carbamate, a significant variation in the final concentration of this compound was observed for each sample analyzed. The Rf values for the dhurrin standard and for the sugarcane variety SP 83-2847 were equal, similar to those for SP 80-3280 and CTC 11 and different from the Rf values for the RB 86-7515 and IAC 86-2480 samples.

The possibility of commercialization of Moro blood oranges in tropical countries such as Brazil was evaluated to verify whether post-harvest management through storage at low temperatures for a period of 60 days can improve the bioactive properties and quality parameters. Moro blood oranges cultivated in Brazil did not contain significant amounts of anthocyanins at the time of harvesting, but these compounds were activated by post-harvest management through storage at low temperatures (4°C and 8°C) for a period of 60 days. The emergence of the anthocyanins in the juices occurred within a few weeks of storage, but the maximum levels were attained after 60 days and at the temperature of 8°C. Cold storage positively influenced other bioactive compounds such as total phenolic compounds, individual phenolic compounds, β-carotene and the antioxidant activity determined by the sequestration of DPPH free radicals. It did not influence the vitamin C content. In addition, storage significantly altered the color, total acidity and pH of the fruits, but it did not prevent its commercial use. The remaining quality parameters were not influenced. It is possible to commercialize these oranges in Brazil through post-harvest management.

The effects of acetylcarvacrol on the reproductive performance of engorged female R. microplus were evaluated. Carvacrol was acetylated by a reaction with acetic anhydride, confirmed by the identification of its melting point and by infrared spectroscopy. Based on the median lethal concentration, females were exposed to sublethal concentrations (3.7, 4.6 and 5.0 μL/mL) of acetylcarvacrol by means of the adult immersion test. The following parameters were evaluated: female weight before oviposition, pre-oviposition period, egg mass weight, egg production index, incubation period, hatching rate, fecundity rate, percentage of reduction in oviposition, percentage of reduction in hatching and product efficacy. The greatest efficacy was observed in the group treated with the highest concentration (91.69%) due to the greater weight reduction in egg mass (34.91 ± 0.02 mg) and the lower hatching rate (7.23 ± 15.50%). Therefore, this compound is a promising alternative for the control of R. microplus infestations.

Knowledge of the chemical composition of Mozambican spirits is extremely important because the studies of potentially toxic compounds have been a determinant factor in quality control. The objectives of this work were to analyze and physicochemically characterize distilled sugarcane spirits and other raw materials from Mozambique on the basis of the standards established by the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA). The samples came from five provinces of southern and central Mozambique, provided by the owners of the stills in the localities of Manhica, Xinavane, Chokwe, Massinga, Mafambisse, Beira and Chimoio. The four samples from Brazil were randomly collected from different regions of Minas Gerais. The parameters analyzed were ethanol, methanol, higher alcohols, aldehydes, volatile acidity, furfural, esters and copper concentrations. The Mozambican spirits produced from different raw materials, compared to Brazilian spirits, contained very variable concentrations of the components analyzed. Mozambican spirits are of much lower quality than Brazilian beverages and are not suitable for consumption.

The ticks Rhipicephalus microplus and Rhipicephalus sanguineus sensu lato (s.l) are of great importance to agriculture, veterinary medicine and public health. Due to a number of problems related to the use of synthetic acaricides, natural products emerge as promising substances for alternative tick control. In the present study, essential oils of Backhousia citriodora, Callistemon viminalis and Cinnamodendron dinisii were extracted by hydrodistillation, characterized by GC-MS and GC-FID and biologically evaluated for acaricidal activity against R. microplus and repellent activity against R. sanguineus s.l. Inhibition of acetylcholinesterase (AChe) by the essential oils was also evaluated. The major constituent of B. citriodora is citral (98.9 %), whereas the essential oil from C. viminalis is rich in 1.8-cineole (78.1 %), α-pinene (12.5 %) and limonene (3.36 %), and that from C. dinisii contains α-pinene (30.8 %), β-pinene (12.5 %) and sabinene (11.3 %) as the principal constituents. The median lethal concentrations (LC 50) estimated for the essential oils on engorged R. microplus females were 3.276 μL.mL-1 for B. citriodora, 8.195 μL.mL-1 for C. dinisii and 8.936 μL.mL-1 for C. viminalis. The essential oil of B. citriodora showed the best repellent effect against unfed R. sanguineus s.l. adults, demonstrating repellent action up to 3 h after application. The essential oil of C. viminalis was able to reduce AChe activity, with an average inhibitory concentration (IC 50) of 0.33 μg mL-1. Thus, these oils can be considered as sources of bioactive compounds for tick control.

Ethyl carbamate was quantified in cachaca using high-performance liquid chromatography with fluorescence detection during the production process and during storage in different types of wooden casks and glass containers, with and without the presence of light. According to the physicochemical analysis, the head and tail fractions are unacceptable for consumption. Ethyl carbamate was detected in sugarcane juice and during fermentation. During distillation, ethyl carbamate levels ranged from the limit of detection to 17.1 μg L−1. Ethyl carbamate increased during storage in wooden casks. The presence (or absence) of light did not affect the formation of ethyl carbamate in cachaca stored in glass containers. Copyright © 2017 The Institute of Brewing & Distilling

Background Nutritional intervention with the use of phytochemicals is an important method for the treatment and prevention of a metabolic syndrome. The objective of this study was to chemically characterize Moro orange juice. The influence of juice intake on metabolic parameters of rats that were obese, diabetic or both by means of body mass management after the activation of anthocyanins during refrigerated storage was also assessed. Results Juice intake reversed most of the metabolic abnormalities exhibited by obese rats, including reduction of body mass and improvement of the biochemical profile. The loss of body mass by diabetic animals and obese and diabetic animals was not attributed to juice intake, but to type I diabetes mellitus. In these animals, no improvement was observed in the biochemical profile, liver enzymes and glycemia, so this treatment model was deemed unfeasible. Conclusion The beneficial effects cannot be explained only by the anthocyanin C3G present in the juice, but rather, by the synergism between all the components. Studies in humans are needed to determine whether the ingestion of this orange can be recommended as an effective strategy to prevent or ameliorate complications of obesity. This article is protected by copyright. All rights reserved.