Variation in the chemical composition of the essential oils of different organs of domesticated Lippia multiflora Moldenke

The essential oils from the different organs of wild and domesticated Lippia multiflora Moldenke, analysed by GPC-FID and GPC-MS, were rich in monoterpenes. These made up 95.0, 94.0, 82.5 and 61.0% of oils from leaves, flowers, stems and roots, respectively, with a predominance of aromatic monoterpenes: p-cymene, thymol, carvacrol and their acetates together made up 44.0 - 74.0% of the oils, along with b-caryophyllene and its oxide (3.0 - 8.4%). Oils from roots differed from those of flowers, leaves and stems by a higher proportion of b-caryophyllene and its oxide (16.0%), and the absence of p-cymene g-terpinene represented respectively, 6.3 - 18.0 and 0.7 - 11.4% of the oils from the other organs. (Z)-β-Ocimene, identified in the oils from flowers (nearly 10%) was absent from oils of leaves, stems and roots. Oils of stems and roots contained very small amounts of hexadecanoïc acid, b-eudesmol, isocaryophyllene and phytol, none of which had previously been reported in oils from the Congo.Key words: Lippia multiflora Moldenke, organs, essential oil, chemical composition

Approvisionnement En Eau Dans La Ville De Brazzaville, Congo

The difficulty of water supply is a major problem faced by the households of Brazzaville in Congo. The objective of this study is to list and identify the different types of water used, and to assess the general hygiene of households. The method used in this prospective study is based on an onsite survey and direct measurement. The survey involves administering a questionnaire to the households in the 9 districts of the city of Brazzaville. 630 households were surveyed. 70 households were drawn in this study and were selected in each borough. There are many sources of water. Overall, 80.16% of households consume water from the SNDE. The survey revealed that 71.00% of households walk on foot to get access to water supply. Plastic cans and buckets are used more in the transportation (43.00 and 37.00 %) and storage (45.00 and 39.00 %) of water. The water storage period is relatively long. It can hold water from 3 days (21.00%) to more than one week (13.00 %) for some households. Analysis of the results of the survey showed that the sources of water supply are diversified. This diversification is due to the phenomenon of shortage and/or repeated water cut recorded by households. Water supply, transport and storage practices, and the cleaning of water containers highlight the precarious conditions of hygiene and sanitation households in the city of Brazzavill

Inside Back Cover: Superacid-Catalyzed Trifluoromethylthiolation of Aromatic Amines (Angew. Chem. Int. Ed. 1/2017)

International audienc

Innenrücktitelbild: Superacid-Catalyzed Trifluoromethylthiolation of Aromatic Amines (Angew. Chem. 1/2017)

International audienc

Superacid-Catalyzed Trifluoromethylthiolation of Aromatic Amines

International audienc

Bio-guided Fractionation of the Ethanolic Extract from Leaves of Trema orientalis Blume (Cannabaceae), a Presumed Antihypertensive Plant from Congo-Brazzaville

International audienceHypertension is a risk factor for cardiovascular disease, which is currently a real public health problem. This disease affects about one billion people worldwide and is responsible for more than 70% of cardiovascular related deaths. Recently, the World Health Organization reported that of the hypertensive cases detected in Congo, only 7% were controlled. Today, there is no lifetime treatment and existing drugs are less accessible by the African population. To treat the disease, the Congolese population uses more the medicinal plants. However, the majority of compounds responsible for the biological activity of these plants are not known. In order to bring out Congolese plants with antihypertensive properties, we focus our interest on Trema orientalis Blume (Canabaceae). An ethanolic extract of the leaves of Trema orientalis was prepared after successive depletion of the organic solvents. Thereafter, a bio-guided fractionation on silica gel of the ethanol extract was carried out. Fractionation monitoring was done by TLC and the results of vasodilating activity measured. The fractions exhibiting the best biological activity allowed a second fractionation process to obtain five fractions which are characteristic of polyphenols, in particular flavonoids, and which exhibited good vasodilating activity on the isolated aorta of rats. Our future work will focus on the identification of these biologically active compounds

Cationic polycyclization of ynamides: building up molecular complexity

International audienc