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The flour beetle (Tribolium confusum du Val) is one of the most important coleopteran pests on stored products, especially cereal grains and flour. Frequent application of chemical pesticides in insect pest management has resulted in numerous side effects such as environmental contamination, threat to human health and non-target organisms, and the development of pest resistance. In the present study, the fumigant toxicity and anti-nutritional effects of rosemary essential oil on flour beetle adults were investigated. Due to the relationship between the chemical compositions of essential oils with their biological effects, the compounds of rosemary essential oil were studied by gas chromatography-mass spectrometry. Rosemary essential oil was rich in terpenic compounds, including the hydrocarbon monoterpenes (28.72%), monoterpenoids (57.03%), hydrocarbon sesquiterpenes (3.09%), and sesquiterpenoids (3.25%). The concentration of 73.5 µl/l air of essential oil caused 90.0% mortality of the pest after 24 h, which was increased to 100% by 48 h. The use of 24-h LC40 and LC50 values of essential oil, respectively equal to 26.7 and 35.5 µl/l air, reduces the nutritional indices of the pest, including consumption index, relative consumption rate, and relative growth rate after 5 and 10 days. In addition, the feeding deterrence index of the mentioned values was estimated at 40.7 and 45.9% after 5 days and 53.4 and 59.5% after 10 days, respectively. Therefore, rosemary essential oil can be introduced as one of the available and efficient agents in the management of flour beetle for further research. [ABSTRACT FROM AUTHOR]

A comprehensive characterization of the phytochemicals present in a blackberry fruit extract by HPLC-TOF-MS has been carried out. The main compounds in the extract were ursane-type terpenoids which, along with phenolic compounds, may be responsible for the bioactivity of the extract. In vitro antioxidant capacity was assessed through Folin–Ciocalteu (31.05 ± 4.9 mg GAE/g d.w.), FRAP (637.8 ± 3.2 μmol Fe2+/g d.w.), DPPH (IC50 97.1 ± 2.4 μg d.w./mL) and TEAC (576.6 ± 8.3 μmol TE/g d.w.) assays. Furthermore, the extract exerted remarkable effects on in vitro cellular antioxidant activity in HUVEC cells at a concentration of 5 mg/mL. Antimicrobial activity of the extract was also tested. Most sensible microorganisms were Gram-positive bacteria, such as E. faecalis, B. cereus and Gram-negative E. coli (MBC of 12.5 mg/mL). IC50 values against colon tumoral cells HT-29 (4.9 ± 0.2 mg/mL), T-84 (5.9 ± 0.3 mg/mL) and SW-837 (5.9 ± 0.2 mg/mL) were also obtained. Furthermore, blackberry extract demonstrated anti-inflammatory activity inhibiting the secretion of pro-inflammatory IL-8 cytokines in two cellular models (HT-29 and T-84) in a concentration-dependent manner. These results support that blackberry fruits are an interesting source of bioactive compounds that may be useful in the prevention and treatment of different diseases, mainly related to oxidative stress. [ABSTRACT FROM AUTHOR]

Aedes aegypti is a vector for the arbovirus responsible for yellow fever, Zika and Chikungunya virus. Essential oils and their constituents are known for their larvicidal properties and are strong candidates for mosquito control. This work aimed to develop a quantitative structure–activity study and molecular screening for the search and design of new larvicidal agents. Twenty-five monoterpenes with previously evaluated larvicidal activity were built and optimized using computational tools. QSAR models were constructed through genetic algorithms from the larvicidal activity and the calculation of theoretical descriptors for each molecule. Docking studies on acetylcholinesterase (AChE) and sterol carrier protein (SCP-2) were also carried out. Results demonstrate that the epoxide groups in the structure of terpenes hinder larvicidal activity, while lipophilicity plays an important role in enhancing biological activity. Larvicidal activity correlates with the interaction of the sterol-carrier protein. Of the 25 compounds evaluated, carvacrol showed the highest larvicidal activity with an LC50 of 8.8 µg/mL. The information included in this work contributes to describing the molecular, topological, and quantum mechanical properties related to the larvicidal activity of monoterpenes and their derivatives. [ABSTRACT FROM AUTHOR]

A comprehensive characterization of the phytochemicals present in a blackberry fruit extract by HPLC-TOF-MS has been carried out. The main compounds in the extract were ursane-type terpenoids which, along with phenolic compounds, may be responsible for the bioactivity of the extract. In vitro antioxidant capacity was assessed through Folin–Ciocalteu (31.05 ± 4.9 mg GAE/g d.w.), FRAP (637.8 ± 3.2 μmol Fe2+/g d.w.), DPPH (IC50 97.1 ± 2.4 μg d.w./mL) and TEAC (576.6 ± 8.3 μmol TE/g d.w.) assays. Furthermore, the extract exerted remarkable effects on in vitro cellular antioxidant activity in HUVEC cells at a concentration of 5 mg/mL. Antimicrobial activity of the extract was also tested. Most sensible microorganisms were Gram-positive bacteria, such as E. faecalis, B. cereus and Gram-negative E. coli (MBC of 12.5 mg/mL). IC50 values against colon tumoral cells HT-29 (4.9 ± 0.2 mg/mL), T-84 (5.9 ± 0.3 mg/mL) and SW-837 (5.9 ± 0.2 mg/mL) were also obtained. Furthermore, blackberry extract demonstrated anti-inflammatory activity inhibiting the secretion of pro-inflammatory IL-8 cytokines in two cellular models (HT-29 and T-84) in a concentration-dependent manner. These results support that blackberry fruits are an interesting source of bioactive compounds that may be useful in the prevention and treatment of different diseases, mainly related to oxidative stress.

By using the classical technology of making dry white wines, which does not involve maceration of the pomace, we can produce standard table wines, light and delicate. This minimises such an objectionable factor as saturation of the wine with extra nitrogenous and phenolic substances and oxidative enzymes. On the other hand, this scheme gives a specific varietal aroma no chance to reveal itself more expressively. The paper overviews briefly the scientific works considering the modes of pomace maceration before fermentation and the use of enzyme preparations in the technology of white table wines. The physicochemical and sensory characteristics of wine materials from Rkatsiteli grapes grown in the south of the Mykolaiv Region have been analysed. This analysis has proved that standard white table wine materials can be obtained both by the traditional method (the so called ‘white’ method) and with the use of short-term maceration of the pomace. Macerating the pomace resulted in obtaining fuller, richer wine materials with a bright aroma and good body. It has been shown that to obtain bright and not too blunt wine materials, the most essential parameter of the maceration process is its low temperature. A pectolytic enzyme preparation used during maceration increased, to some extent, the mass concentration of phenolic substances, the reduced extract, the optical density, and the concentration of terpene alcohols. Besides, it allowed fuller revealing a wine’s aromatic profile. The research has resulted in establishing that there is regularity in how the concentration of terpene alcohols changes with different temperature conditions of steeping the pomace. It has been shown that the maximum concentration of terpenes responsible for the varietal aroma is best retained in wine materials when the maceration temperature is 5°C. A rise in the pomace maceration temperature to 20°C led to a decrease in the concentration of labile terpene alcohols, so it should be avoided in producing quality wines. Studying different maceration modes has allowed recommending a certain method to manufacture full-bodied, well-structured white table wines with a pronounced varietal aroma. This method involves adding the enzyme preparation Depectil CLARIFICATION to the pomace and macerating it for 12 hours at 5°C.

By using the classical technology of making dry white wines, which does not involve maceration of the pomace, we can produce standard table wines, light and delicate. This minimises such an objectionable factor as saturation of the wine with extra nitrogenous and phenolic substances and oxidative enzymes. On the other hand, this scheme gives a specific varietal aroma no chance to reveal itself more expressively. The paper overviews briefly the scientific works considering the modes of pomace maceration before fermentation and the use of enzyme preparations in the technology of white table wines. The physicochemical and sensory characteristics of wine materials from Rkatsiteli grapes grown in the south of the Mykolaiv Region have been analysed. This analysis has proved that standard white table wine materials can be obtained both by the traditional method (the so called ‘white’ method) and with the use of short-term maceration of the pomace. Macerating the pomace resulted in obtaining fuller, richer wine materials with a bright aroma and good body. It has been shown that to obtain bright and not too blunt wine materials, the most essential parameter of the maceration process is its low temperature. A pectolytic enzyme preparation used during maceration increased, to some extent, the mass concentration of phenolic substances, the reduced extract, the optical density, and the concentration of terpene alcohols. Besides, it allowed fuller revealing a wine’s aromatic profile. The research has resulted in establishing that there is regularity in how the concentration of terpene alcohols changes with different temperature conditions of steeping the pomace. It has been shown that the maximum concentration of terpenes responsible for the varietal aroma is best retained in wine materials when the maceration temperature is 5°C. A rise in the pomace maceration temperature to 20°C led to a decrease in the concentration of labile terpene alcohols, so it should be avoided in producing quality wines. Studying different maceration modes has allowed recommending a certain method to manufacture full-bodied, well-structured white table wines with a pronounced varietal aroma. This method involves adding the enzyme preparation Depectil CLARIFICATION to the pomace and macerating it for 12 hours at 5°C. [ABSTRACT FROM AUTHOR]

The producers of essential oils from the Republic of Moldova care about the quality of their products and at the same time, try to capitalize on the waste from processing. The purpose of the present study was to analyze the chemical composition of lavender (Lavanda angustifolia L.) essential oil and some by-products derived from its production (residual water, residual herbs), as well as to assess their “in vitro” antimicrobial activity. The gas chromatography-mass spectrometry analysis of essential oils produced by seven industrial manufacturers led to the identification of 41 constituents that meant 96.80–99.79% of the total. The main constituents are monoterpenes (84.08–92.55%), followed by sesquiterpenes (3.30–13.45%), and some aliphatic compounds (1.42–3.90%). The high-performance liquid chromatography analysis allowed the quantification of known triterpenes, ursolic, and oleanolic acids, in freshly dried lavender plants and in the residual by-products after hydrodistillation of the essential oil. The lavender essential oil showed good antibacterial activity against Bacillus subtilis, Pseudomonas fluorescens, Xanthomonas campestris, Erwinia carotovora at 300 μg/mL concentration, and Erwinia amylovora, Candida utilis at 150 μg/mL concentration, respectively. Lavender plant material but also the residual water and ethanolic extracts from the solid waste residue showed high antimicrobial activity against Aspergillus niger, Alternaria alternata, Penicillium chrysogenum, Bacillus sp., and Pseudomonas aeroginosa strains, at 0.75–6.0 μg/mL, 0.08–0.125 μg/mL, and 0.05–4.0 μg/mL, respectively.

The aim of the current study was to demonstrate the presence of different secretory structures of thyme essential oil on the leaf surfaces identified by SEM apparatus, and the phytonutrients content of aqueous extracts of aerial parts of Tunisian Thymus hirtus Willd. Ssp. algeriensis Boiss. and Reut. and also to compare the difference in terpenic compounds at three developmental stages. The phenolic and terpenic compounds found in thyme aerial parts were determined by HPLC and GC/MS apparatus, respectively. Two kinds of glandular trichome (peltate and capitate) are the main site of production and secretion of essential oils. Two types of capitate hairs were observed, the first one was with short stalk, neck and cellular secretory head, and the second one was with long stalk composed of one to many cells. Non glandular trichomes are densely distributed in the Thymus hirtus Willd. Ssp. algeriensis Boiss. and Reut. species. The results obtained by chromatographic analysis revealed the richness of thyme, harvested during vegetative phase, in bioactive phytochemicals, that include gallic acid, coumaric acid, catechin, rutin and quercetin compared to other samples. Terpenic and phenolic compounds levels increased over stages. A total of 65 terpenic constituents and others identified by GC/MS and representing 93.01 to 99.59% of the total essential oil. Antioxidant and antibacterial activities varies throughout growing season in aerial parts of Thymus hirtus Willd. Ssp. algeriensis Boiss. and Reut. At vegetative stage, the essential oils showed the highest antioxidant potential and inhibition zone (IZ) on differents bacterial strains, to the high effect as chloramphenicol and Fosfomycin. • Description of morphological structures of Thymus algeriensis parts Essential oil secretory structures Glandular trichomes (peltate, capitate) Non-glandular trichomes Antioxidant and antibacterial activity. [ABSTRACT FROM AUTHOR]

The producers of essential oils from the Republic of Moldova care about the quality of their products and at the same time, try to capitalize on the waste from processing. The purpose of the present study was to analyze the chemical composition of lavender (Lavanda angustifolia L.) essential oil and some by-products derived from its production (residual water, residual herbs), as well as to assess their "in vitro" antimicrobial activity. The gas chromatography-mass spectrometry analysis of essential oils produced by seven industrial manufacturers led to the identification of 41 constituents that meant 96.80–99.79% of the total. The main constituents are monoterpenes (84.08–92.55%), followed by sesquiterpenes (3.30–13.45%), and some aliphatic compounds (1.42–3.90%). The high-performance liquid chromatography analysis allowed the quantification of known triterpenes, ursolic, and oleanolic acids, in freshly dried lavender plants and in the residual by-products after hydrodistillation of the essential oil. The lavender essential oil showed good antibacterial activity against Bacillus subtilis, Pseudomonas fluorescens, Xanthomonas campestris, Erwinia carotovora at 300 μg/mL concentration, and Erwinia amylovora, Candida utilis at 150 μg/mL concentration, respectively. Lavender plant material but also the residual water and ethanolic extracts from the solid waste residue showed high antimicrobial activity against Aspergillus niger, Alternaria alternata, Penicillium chrysogenum, Bacillus sp., and Pseudomonas aeroginosa strains, at 0.75–6.0 μg/mL, 0.08–0.125 μg/mL, and 0.05–4.0 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

AUSTERWEIL (1946) a émis le premier l'hypothèse que l'arôme de muscat serait dû au linalol ou à ses dérivés. Dans un travail fondamental resté classique, CORDONNIER (1956) montre que les extraits par l'éther de pétrole d'un vin de muscat présentent' des taches dont les Rf et les réactions colorées avec l'acide sulfurique concentré laissent supposer la présence de limonène, de linalol, de géraniol et d'α-terpinéol dans la composition de l'arôme de ce type de vin. BAYONOVE et CORDONNIER (1970 a et b) confirment la présence du linalol dans différents Muscats : Alexandrie, Hambourg, Frontignan, Fleur d'Oranger, Ottonel, Reine des Vignes ; ils montrent également l'absence de ce corps, tout au moins en quantité notable, dans le Cabernet-Sauvignon, le Merlot, le Syrah, le Piquepoul et le Chasselas.

Une étude systématique d'une centaine de substances témoins nous laisse supposer l'existence dans le raisin muscat des substances signalées dans l'e tableau I dont les caractéristiques chromatographiques en phase gazeuse et sur couche mince ont été étudiées en détail. Il y a dans tous les cas correspondance entre le pic, la tache et ceux de la substance témoin. La seule technique de chromatographie sur couche mince laisse planer un doute sur la présence de citronellol et de farnésol, mais dans tous les extraits analysés en chromatographie en phase gazeuse ces substances n'existent pas en quantité suffisante pour être détectées. La présence de limonène et de myrcène, dont les pics coïncident avec ceux de substances présentes dans les extraits en chromatographie en phase gazeuse, n'est pas confirmée par la chromatographie sur couche mince.