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The large surface area of Lake Victoria (about 68,800 km2) makes it vulnerable to high atmospheric deposition of chemical pollutants. We present measurements of polychlorinated biphenyls (PCBs) from the lake's atmospheric environment. High volume air (24 h) samples were collected within the northern Lake Victoria watershed in Uganda over two periods; 1999–2004 [at Kakira (KAK) and Entebbe (EBB)] and 2008–2010 (at EBB only). Precipitation samples were also collected monthly during the 2008–2010 period at EBB. Analysis for PCBs was done using GC-μECD in a dual column approach. The ranges of ΣPCB concentrations in the KAK air samples were 154–462 pg m−3 (KAK 1999–2000), 26.7–226 pg m−3 (KAK 2003–2004), 27.0–186 pg m−3 (EBB 2003), 46.8–174 pg m−3 (EBB 2004), 19.2–128 pg m−3 (EBB 2008), 45.8–237 pg m−3 (EBB 2009) and 65.6–244 pg m−3 (EBB 2010). The di-, tri-, tetra- and penta-PCBs were predominant in air sample sets while the tetra- and penta-PCBs were predominant in precipitation samples. The mean flux of ΣPCBs in the precipitation samples was 26.9 ng m−2 (range of 14.8–41.5 and median of 27.5). Concentrations at EBB were lower than those reported elsewhere for urban sites in the East and Central African region. Multivariate analysis and analysis of air mass movements suggested influence of combustion sources on the PCB profiles from the region, especially, from the major East African urbanized regions.

In Uganda, malaria has been ranked as a leading cause of morbidity and mortality with Apac District having one of the highest transmission rates. The objective of this study was to assess the use of medicinal plants in preventing and treating malaria and to determine the traditional concept of malaria in Cegere Sub-County, Apac. A snowball sampling method was used to work through a network of informants. Ninety respondents, including traditional healers, were interviewed using focus group discussions and questionnaires. Twenty plant species from 15 families were used for preventing and treating malaria. Most of the plants were herbs (50%), and leaves (64%) were the most frequently used parts. Schkuhria pinnata (Lam.) Kuntze ex Thell. was the most frequently cited plant for treating malaria, mentioned by 77% of the respondents. Traditionally, malaria was known as atipa and was treated ritually. Fewer medicinal plant species were used to treat malaria in Apac compared to other parts of Uganda.

Ethnopharmacological relevance The aim of the survey was to document medicinal plants used in malaria treatment by Prometra (Promocion de la medicina tradicional amazonica) Traditional Medical Practitioners (TMPs) of Uganda and for search of new antiplasmodial herbal medicines (HMs) for further phytochemical analysis. Materials and methods In this study, semi structured guided open and close ended questionnaires were used. Focus group discussions were conducted and key informants were chosen within the TMPs who helped in further discussions of how the herbal remedies where collected, prepared and administered. Results A sample size of 51 respondents was randomly selected among the TMPs with the help of their leader. 86 species distributed over 81 genera and 39 families were reportedly being used as herbal remedies in malaria treatment. The TMPs use symptoms like high temperature, shivering, among others in malaria diagnosis an indication that they understand malaria. They emphasized the use of leaves and bark in treatment because they can regenerate and therefore ensure sustainable use of plants rather than the use of roots which would be destructive. These TMPS treat and also advise their patients on preventive measures against malaria attacks like sleeping under mosquito nets, clearing bushes near homesteads, among others which is an indication that they help in the prevention and mitigation of malaria incidences and prevalence in the areas where they live. The Informant Consensus Factor (FIC) value of 0.8 demonstrated that the TMPs of Prometra-Uganda tend to agree with each other in terms of the plant species they use in malaria treatment an indication of quality control in as far as administration of the herbal remedies. Vernonia amygdalina Delile, Bidens pilosa L., Justicia betonica L. were highly cited as being used in malaria treatment with frequencies of mention of 38, 28 and 25, respectively. Conclusion TMPs of Prometra-Uganda understand and treat malaria using the available plant diversity from their huge forest and the herbal gardens within Buyija forest. The healers are very keen at plant conservation which is a good practice. Species like Justica betonica may be investigated further for antiplasmodial assays to justify its efficacy.

Cotton fabrics were dyed with natural dyes derived from the crude bark extracts of Albizia coriaria, Morinda lucida, Syzygium cordatum and Vitellaria paradoxa dye-yielding plants collected in 2004 from Mukono and Mbale districts of Uganda. Natural dyes are becoming very important in industry for their less toxic tendencies as compared to synthetic dyes. They are friendly to the environment and hence their increasing demand worldwide. Many new enterprises, of different sizes, have began to cultivate, extract and apply natural dyes. Dyeing was carried out using the simultaneous mordanting method with 10% (o.w.f) of four selected mordants. CIELab coordinates, Chroma (C) and Hue (H) values were found to be dependent on type of mordant and nature of the phenolic composition of the crude extracts. The colour fastness values, both to light and washing, were very good and of textile importance. The colour absorption values (K/S) were calculated using the Kubelka–Munk equation from reflectance values and the same varied from plant to plant due to differences in molecular structures and substantivity to the cotton fabrics. The mordanting process resulted into varied values of colour depth, chroma (C) and hues (H) with significant changes in lightness values (L), and mordant dependent. Colour fastness properties to light and washing were good, between 3 and 4, suitable for textile application. Key words: Extraction, characterization, natural dyes, selected plants, Uganda.

Two commercially important fish species, Nile perch (Lates niloticus) and Nile tilapia (Oreochromis niloticus) belonging to different trophic levels were collected from the Napoleon Gulf and Thurston Bay in Lake Victoria. Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) were extracted from the fish muscles and livers using the (13)C isotope dilution method, followed by multiple column chromatography clean-up. Analysis was achieved by a high resolution gas chromatography coupled with a high resolution mass spectrometer. The concentrations of analytes ranged from 0.07 to 0.59pgg(-1) fresh weight (fw) and 0.3-19.0pgg(-1) in L. niloticus and 0.06-0.18 and 0.2-15.7pgg(-1) in O. niloticus, for ∑PCDD/Fs and ∑dl-PCBs, respectively. Differences in congener concentrations were observed between the two fish species and study sites, and this was attributed to differences in feeding habits and trophic levels. World Health Organization-toxic equivalents (WHO-TEQs) were in the range 0.01-0.16pgTEQg(-1) for the PCDD/Fs and 0.001-0.74pgTEQg(-1) for the dl-PCBs. The TEQ values in the present study were lower compared to those of most fish samples reported in literature and were within permissible levels recommended by the European Union, implying that the fish was fit for human consumption.

Residual concentrations of organochlorine pesticides in vegetables cause concern because of their adverse health effects. Pesticides have been applied in agricultural production and vector control in Uganda. Vegetables may absorb high residual levels of cyclodienes necessitating regular monitoring. Carrots are commonly consumed in Uganda as raw salads or components of different dishes. A gas chromatograph with electron capture detector was used to quantify organochlorine pesticides. Pesticide residues were confirmed by gas chromatography with a mass spectrometer. Trace amounts of 4,4′-dichlorodiphenyltrichloroethane (DDT), 2,4′-DDT, 2,4′-dichlorodiphenylchloroethane (DDE), α- endosulphan, β-endosulphan, α-lindane, γ-lindane and dieldrin were detected in carrots. Levels of organochlorine residues in carrots were below the maximum residue limits considered safe for human consumption by Codex Alimentarius and the European Union Commission.

In the first study of its kind in Africa, PAHs were measured in high volume (24 h) air samples collected from two sampling stations, at Kakira and Entebbe (KAK and EBB, respectively) within the Lake Victoria watershed in Uganda, to assess source contributions and generate a baseline reference data set for future studies in the East African region. Sampling was conducted over two periods [2000-2004 (KAK and EBB1) and 2008-2010 (EBB2)]. The samples were extracted by accelerated solvent extraction and analyzed for 30 PAHs by GC-MS. The mean total PAH concentrations (ng/m(3)) were found to be 74.3 (range; 19.3-311, N = 39) for KAK, 56.8 (range; 13.3-126, N = 22) for EBB1 and 33.1 (range; 4.91-108, N = 56) for EBB2. The 3-ringed PAHs were the most predominant group with mean concentrations of 35.9 ng/m(3)(EBB1), 30.5 ng/m(3)(KAK) and 23.2 ng/m(3)(EBB2). Naphthalene had an exceptionally high mean concentration (21.9 ng/m(3)) for KAK compared to 0.44 and 0.39 ng/m(3) in EBB1 and EBB2 respectively, likely due to intensive agricultural operations nearby KAK. Principal component and diagnostic ratio analyses showed that the measured levels of PAHs were associated with mixed sources, combustion of petroleum, and biomass being the major sources.

Fresh and pasteurized milk samples from Kampala markets were analyzed for organochlorine pesticides using a gas chromatograph equipped with an electron capture detector. Five organochlorine pesticides, namely; aldrin, dieldrin, endosulfan, lindane, DDT and its metabolites were detected in the milk samples and confirmed with a gas chromatograph equipped with a mass spectrometer [GC-MS]. The mean values are expressed in mgkg(-1) milk fat (mf) basis. The mean concentration in the fresh milk (n=54) were: 0.026 ± 0.003 mg kg(-1) mf; 0.002 ± 0.0003 mg kg(-1), below the detection limit; 0.007 ± 0.003 mg kg(-1), 0.009 ± 0.002 mg kg(-1) milk fat for lindane, endosulfan dieldrin and aldrin, respectively. The mean concentrations of p,p'-DDE; p,p'-DDT and o,p'-DDT were 0.009 ± 0.002 mg kg(-1); 0.033 ± 0.007 mg kg(-1) and 0.008 ± 0.001 mg kg(-1) mf, respectively in the fresh milk samples. In the pasteurized milk samples (n=47), the mean concentrations recorded were: 0.008 ± 0.003 mg kg(-1), 0.025 ± 0.004 mg kg(-1), and 0.007 ± 0.001 mg kg(-1), respectively for p,p'-DDE; p,p'-DDT and o,p'-DDT. Alpha and beta-endosulfan recorded the concentration below the detection limit and the mean of 0.022 ± 0.001 mg kg(-1) mf, 0.005 ± 0.002 mg kg(-1) mf, and 0.006 ± 0.0002 mg kg(-1) mf, respectively for lindane, dieldrin and aldrin. Although, most of the residues detected were above the residue limits set by the FAO/WHO (2008), bioaccumulation of these residues is likely to pose health risks to the consumers of milk in Uganda.

Two anthocyanins were isolated from ornamental reddish flowers of Plumeria rubra L. (Apocynaceae) by a combination of chromatographic techniques. Their structures were elucidated mainly by the use of homo- and heteronuclear nuclear magnetic resonance spectroscopy and high-resolution electrospray mass spectrometry. The anthocyanin cyanidin 3-O-β-(2″-glucopyranosyl-O-β-galactopyranoside) (75%), has previously been isolated only from Cornus suecica (Cornaceae) fruits, while the other (20%) was identified as cyanidin-3-O-β-galactopyranoside. This is the first report of the anthocyanins responsible for the attractive colours of the flowers of red frangipani.

Organochlorine (OC) residues were analysed in 117 sediment samples collected from four bays of the Uganda side of Lake Victoria. The sediments were collected with a corer at a depth of 0–20 cm, and extracted for OC residues using a solid dispersion method. The extracts were cleaned using gel permeation chromatography and analysed for pesticide residues using a gas chromatograph (GC) equipped with an electron capture detector. The results were confirmed using a GC equipped with a mass spectrometer (MS). A total of 16 OC residues, most of them persistent organic pollutants (POPs) were identified and quantified. The OC residue levels were expressed on an oven dry weight (d.w.) basis. Endosulphan sulphate, in the range of 0.82–5.62 μg kg−1 d.w., was the most frequently detected residue. Aldrin and dieldrin were in the ranges of 0.22–15.96 and 0.94–7.18 μg kg−1 d.w., respectively. DDT and its metabolites lay between 0.11–3.59 for p,p′-DDE, 0.38–4.02 for p,p′-DDD, 0.04–1.46 for p,p′-DDT, 0.07–2.72 for o,p′-DDE and 0.01–1.63 μg kg−1 d.w. for o,p′-DDT. The levels of γ-HCH varied from 0.05 to 5.48 μg kg−1 d.w. Heptachlor was detected only once at a level of 0.81 μg kg−1 d.w., while its photo-oxidation product, heptachlor epoxide, ranged between non-detectable (ND) to 3.19 μg kg−1 d.w. Chlordane ranged from ND to 0.76 μg kg−1 d.w. Based on the threshold effect concentration (TEC) for fresh water ecosystems, aldrin and dieldrin were the only OCs that seemed to be a threat to the lake environment.

One new drimane-type sesquiterpenoid, named ugandenial A ( 1), was isolated from the ethyl acetate extract of the bark of Warburgia ugandensis (Canellaceae) together with eight known drimane-type sesquiterpenoids: 11 alpha-hydroxycinnamosmolide ( 2), warburganal ( 3), polygodial ( 4), mukaadial ( 5), dendocarbin A ( 6), 9 alpha-hydroxycinnamolide ( 7), dendocarbin L ( 8) and dendocarbin M ( 9). Their structures were established by detailed spectroscopic analysis. In addition a keto-enol equilibrium was demonstrated for compound 1 through a detailed NMR analysis run in CD(2)Cl(2) at 190 K. Cytotoxicity of the isolated compounds against KB cells was evaluated.

Information on historical deposition of persistent organic pollutants (POPs) for African lakes is very limited. We investigated historical deposition trends and sources of POPs in sediment cores from Lakes Victoria (SC1), Bujuku (Buju2) and Mahoma (Maho2). The latter two lakes are situated in the Rwenzori mountain range in western Uganda. SC1 was taken from a central depositional area within the Ugandan part of the lake. Profiles in Buju2 and Maho2 were used as a reference for historical atmospheric deposition. For the post-1940 sediment deposits in SC1, average focusing factor-adjusted fluxes (FFFs) of ΣDDTs, polychlorinated biphenyls (ΣPCBs), hexachlorocyclohexanes (ΣHCHs) and chlordanes (ΣCHLs) were 390, 230, 210 and 120 ng m(-2) yr(-1). Higher fluxes of ΣDDTs, ΣPCBs, and ΣCHLs were observed in Buju2 and Maho2. The average FFF of HCB in Buju2 was the highest while the values for Maho2 and SC1 were similar. The endosulfan FFFs in SC1 were lower than in the alpine lake cores. Generally, Buju2 was a better reference for historical atmospheric deposition of POPs than Maho2 probably due to distortion of the latter's profile by Lake Mahoma's forested catchment. Profiles of p,p'-DDE, ΣCHLs and HCB in SC1 were consistent with atmospheric deposition while profiles of PCBs and HCHs were indicative of particle-bound loadings from additional sources. Profiles of endosulfans, DDTs, and chlordanes were consistent with influence of other factors such as anoxia, and dilution. Further studies of spatial resolution of historical deposition, especially in near-shore deposition areas of the lake are recommended.

Pres de 10 % des 80 chimpanzes composant la communaute de chimpanzes sauvages (Pan troglodytes schweinfurthii) de Sebitoli, dans le parc national de Kibale en Ouganda, presentent des phenotypes faciaux singuliers. L'etiologie de cette malformation est inconnue mais des etudes menees sur des groupes de macaques au Japon et a Hong Kong severement affectes par des anomalies des membres (jusqu'a 17 % des individus dans les groupes de macaques approvisionnes en nourriture potentiellement contaminee par des pesticides) suspectent une origine congenitale liee aux agents teratogenes contenus dans les pesticides. Une etude a donc ete menee du 06/03/14 au 15/05/14 afin de mieux connaitre les consequences physiologiques d'une telle malformation chez les chimpanzes de Sebitoli et leur exposition aux pesticides utilises autour de la zone du parc. Des observations de type ''focal sampling'' d'une et dix minutes ainsi que des observations de type ''scan sampling'' toutes les minutes ont ete effectuees sur les chimpanzes sauvages (27 individus dont 8 atteints de dysplasie faciale) en cours d'habituation par le « Sebitoli Chimpanzee Project » dirigee par S. Krief. Afin de tester l'hypothese d'une origine de la malformation liee a la pollution environnementale, des entretiens ont ete effectues aupres d'agriculteurs cultivant du mais et/ou du the a la bordure du parc. Comme les chimpanzes pillent le mais et pratiquent la geophagie, 123 echantillons de sol, sediment et de mais ont ete recoltes dans le but de mesurer les residus de produits chimiques. Les travaux ethnographiques et agronomiques ont ete effectues en collaboration avec l’equipe du departement de chimie de l'universite de Makerere (Kampala, Ouganda). Les observations conduites sur les chimpanzes ont permis de mettre en evidence un gene respiratoire associee a la dysplasie faciale observee : les individus a dysplasie faciale ouvrent plus souvent la bouche que les individus normaux lors des activites de repos, de deplacement et d'alimentation, et leur rythme d’ingestion d’aliments sauvages (Ficus dawei) est egalement plus lent. Les entretiens ont revele que l'usage local de produits chimiques etait principalement freine par leurs couts eleves, y compris pour les petites exploitations de the. Cependant, la culture de the consomme une quantite importante d'herbicides et de fertilisants, ce qui entraine probablement une pollution environnementale sur le long terme. Au total, cinq produits chimiques ont ete designes candidats pour une cause toxique intra-uterine de la malformation faciale des chimpanzes. Mais excepte le mancozeb qui ne semble pas avoir d'effets teratogenes, il est impossible de cibler plus precisement un intrant chimique parmi ceux utilises regulierement a savoir : un fertilisant (le NPK), un insectide (la cypermethrine) et deux herbicides (le 2,4-D et le glyphosate). Les analyses en cours des echantillons de sol, sediments et mais recoltes permettront d'evaluer l'exposition reelle des chimpanzes aux pesticides et plus largement, l'exposition de la population humaine et de la faune et flore du parc national.

The anthocyanins, cyanidin 3-O-(6 00 -O-a-rhamnopyranosyl-b-glucopyranoside) (1) and pelargonidin 3-O-(6 00 -O-a-rhamnopyranosyl-b-glucopyranoside) (2), were isolated from the ornamentalflowers of a UgandanHippeastrumcultivar by a combination of chromatographictechniques, and their structures were elucidated mainly by the use of homo- and heteronuclear nuclear magnetic resonance spectroscopy and electrospray mass spectrometry. The same anthocyanins were foundin six differentHippeastrumcultivars purchased inNorway.However, the absolute amount of the anthocyanins (0.08‐1.79 mg/g, fresh weight) and the relative proportions of the individual anthocyanins varied from cultivar to cultivar (13.2‐ 96.5% of 1). The colours of the fresh petals of the three cultivars ‘Red Lion’, ‘Royal Velvet’ and ‘Liberty’ were described by the CIELab coordinates L * (lightness), C * (chroma) and hab (hue angles). All the cultivars showed hue angles corresponding to scarlet nuances (hab = 22‐358), with the highest value in ‘Red Lion’. The most reddish petals (in ‘Royal Velvet’) contained the highest relative proportion of 1. Thus, the in vivo colours of these cultivars seem to be correlated with the relative proportions of individual anthocyanin in the petals. # 2006 Elsevier B.V. All rights reserved.

Nile tilapia and Nile perch samples from Lake Victoria were analyzed for lindane (gamma-1,2,3,4,5,6-hexachlorocyclohexane), aldrin (1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-1,4:5,8-dimethanonaphthalene), alpha-endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3- benzo(e) dioxathiepin-3-oxide), dieldrin (1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-1,4,5,8-dimethanonaphthalene), DDE (p,p'-1,1-dichloro-2,2-bis-(4-chlorophenyl)ethylene), and DDT (p,p'-1,1,1-trichloro-2,2-bis-(4-chlorophenyl)ethane). No significant difference (alpha = 0.05) in the residue levels between fish types for lindane, alpha-endosulfan, p,p'-DDE, p,p'-DDT, and dieldrin was observed. The aldrin levels in Nile perch (Lates niloticus) were significantly higher than the levels in Nile tilapia (Oreochromis niloticus). No difference was observed in the distribution of residues in the different parts of Nile tilapia, although a difference for p,p'-DDE was observed in the Nile perch. No significant difference was observed in the average fat content of the tissue of Nile perch and Nile tilapia; however, the distribution of fat was significantly different in the different parts of the fish, with the abdominal portion having the highest amount of fat. There was no correlation observed in this study between fat content and organochlorine concentration. Lower p,p'-DDT residues levels compared with the p,p'-DDE levels observed in this study indicate that DDT is no longer in use. The levels of organochlorine pesticide residues found in fish samples in this study were below the FAO, U.S. FDA, Australian, and German extraneous residue limits and maximum residue limits. The concentration of organochlorine residues in surface water within the Napoleon Gulf of Lake Victoria was below detection limit (0.1 microg L(-1)).

The same anthocyanins, cyanidin 3-(6″-O-α-rhamnopyranosyl-β-glucopyranoside) (1), and cyanidin-3-O-β-glucopyranoside (2), were isolated from extracts of red fruits of Rubus pinnatus Willd. and purple-black fruits of Rubus rigidus Sm. using Amberlite XAD-7 column chromatography, Sephadex LH-20 gel filtration and preparative HPLC. Their structures were elucidated by a combination of chromatography, homo- and heteronuclear NMR techniques. The relative amounts of 1 and 2 in R. rigidus were 59.4% and 40.6%, respectively, while in R. pinnatus, the relative amounts were 58.6% and 41.4%, respectively.

Ethnopharmacological relevance The plant Neoboutonia macrocalyx has been reported in traditional medicine to be used in the treatment of malaria. Aim of the study To study the in vitro antiplasmodial activity of compounds from the stem bark of Neoboutonia macrocalyx. Materials and methods Compounds were extracted and purified from stem bark of Neoboutonia macrocalyx and their structure identified and confirmed by spectroscopic methods. The crude ethyl acetate extract, aqueous extract and the isolated compounds were evaluated for antiplasmodial activity against the chloroquine sensitive Sierra Leone I (D6) and chloroquine-resistant Indochina I (W2) strains of Plasmodium falciparum. Results Chemical investigation of the ethyl acetate extract of Neoboutonia macrocalyx bark resulted in the identification of one new diterpenoid; neoboutomacroin (1) in addition to the four known compounds which included, a phenanthrene; 3,6-dihyroxy-1,7-dimethyl-9-methoxyphenanthrene (2), a sterol; 3-O-Acetyloleuritolic acid (3) and two diterpenoids; simplexin (4) and montanin (5). Compounds 1 and 5 displayed good antiplasmodial activity of IC50 values less than 10 μg/mL against both strains. However, all the compounds tested displayed high cytotoxic activity against MRC5 cell line with IC50 less than 10 μM. Conclusions Despite an indirect in vitro antiplasmodial activity of some compounds isolated from the stem bark of Neoboutonia macrocalyx, the identification of these bioactive compounds indicates that they may play a role in the pharmacological properties of this plant.

Polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and polybrominated diphenyl ethers (PBDEs) were analyzed in sediments and fish from the Murchison Bay of Lake Victoria by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS). Average concentrations of total (Σ) PCDD/Fs and ΣPBDEs in sediments ranged from 68.8 to 479 pg g(-1) dry weight (dw) and 60.8 to 179 pg g(-1) dw, respectively. Contamination levels of sedimentary PCDD/Fs and PBDEs were low to moderate compared to other urbanized regions worldwide. The concentrations in different fish species (Nile perch; Lates niloticus and Nile tilapia; Oreochromis niloticus) were 5.32 to 49.0 pg g(-1) wet weight (ww) for PCDD/Fs and 59.3 to 495 pg g(-1) ww for PBDEs. Higher concentrations of the pollutants were found in L. niloticus than O. niloticus, which could be attributed to species differences in feeding habits and lifestyles. World Health Organization-toxic equivalents (WHO2005-TEQs) for PCDD/Fs ranged from 0.08 to 0.33 pgTEQg(-1) dw and 0.001-0.14 pg TEQg(-1) ww in sediments and fish, respectively. The TEQ values were low compared to the data for fresh water fish reported in literature and within a permissible level of 3.5 pg g(-1) ww recommended by the European Commission. Based on the Commission set value and minimum risk level criteria formulated by the Agency for Toxic Substances and Disease Registry, the fish from the Murchison Bay was fit for human consumption.

International audience; Neoboutonia macrocalyx is used by people in south western Uganda around Kibale National Park in the treatment of malaria. Phytochemical investigation on the leaves of this plant led to the isolation of nine cycloartane triterpenes (1-9) and one phenanthrene; 7-methoxy-2,8 dimethyl-9,10-dihydrophenantherene-3,6 diol (10) along with three known compounds which included 22-de-O-acetyl-26-deoxyneoboutomellerone (11), mellerin B (12) and 6-hydroxystigmast-4-en-3-one (13). The chemical structures of the compounds were established mainly through a combination of spectroscopic techniques. The isolated compounds were evaluated for antiplasmodial activity against the chloroquine-resistant FcB1/Colombia strain of Plasmodium falciparum and for cytotoxicity against the KB (nasopharyngeal epidermoid carcinoma) and MRC-5 (human diploid embryonic lung) cells. Seven out of 13 compounds exhibited good antiplasmodial activity with IC50 of ⩽5μg/ml with two compounds exhibiting low cytotoxicity and five compounds having significant cytotoxicity.

High volume air and precipitation samples were collected close to the shore of Lake Victoria at Entebbe, Uganda, between October 2008 and July 2010 inclusive. Polybrominated diphenyl ethers (PBDEs) and alternative flame retardants (AFRs) were analyzed by GC-MS. BDEs 47, 99, and 209 were the predominant PBDEs with mean concentrations (in air) of 9.84, 4.38, 8.27 pg m(-3) and mean fluxes in precipitation of 3.40, 6.23, and 7.82 ng m(-2) sample(-1), respectively. 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and hexabromocyclododecane (HBCDD), anti- and syn-Dechlorane plus were detected at levels comparable with those of PBDEs. Both PBDEs and AFRs in air generally increased from 2008 to 2010. Elevated PBDE concentrations in air were associated with slow moving low altitude air masses from the region immediately adjacent to the lake, while low concentrations were mostly associated with fast moving westerly and southwesterly air masses. Analysis of the octa- and nona-BDE profiles suggested photolysis and pyrolytic debromination of BDE-209 in the air samples. The highly halogenated and most abundant PBDEs and AFRs in air also predominated in precipitation samples. This is the first study to report flame retardants in high volume air samples and precipitation in Equatorial Africa.

Polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs) were analyzed in surface sediments (

Neoboutonia macrocalyx est originaire d’un arbre des forêts montagneuses de basse altitude des régions tropicales de l'Afrique de l'Est. Ses feuilles sont utilisées en médecine traditionnelle dans le traitement du paludisme par les populations localisées sur le pourtour Sud-Ouest du Parc National de Kibale, en Ouganda. Nous avons observé, par ailleurs, que le bois mort du tronc de cette même espèce était consommé de façon très occasionnelle par certains chimpanzés des communautés de Kanyawara et de Sebitoli (Parc National de Kibale). Les chimpanzés utiliseraient-ils également cette plante pour traiter leurs accès palustres ? Nous avons alors récolté les différentes parties de cette espèce dans le Parc National de Kibale. Trois types d’extraits de polarité croissante (avec l’acétate d’éthyle, le méthanol et l’eau) ont été réalisés afin d’évaluer leur activité et de rechercher les molécules responsables des activités observées. Ces extraits ont montré une bonne activité antiplasmodiale, en particulier l’extrait à l’acétate d’éthyle des feuilles. L’investigation phytochimique de cet extrait guidé par l’activité biologique a conduit à l’isolement de 9 cycloartane triterpéniques nouveaux (1-9), un phénanthrène nouveau, le 7-methoxy-2,8 dimethyl-9,10-dihydrophenantherene-3,6 diol (10), ainsi que 3 composés connus, la 22-dé-O-acétyl-26-désoxynéoboutomellerone (11), la mellerine B (12) et le 6-hydroxystigmast-4-èn-3-one (13). La structure chimique des composés a été principalement établie d’après un ensemble de techniques spectroscopiques, donc principalement de la résonnance magnétique nucléaire (RMN). Les composés isolés ont été évalués pour leur activité antiplasmodiale sur la souche chloroquino-résistante de Plasmodium falciparum FcB1 ainsi que pour leur cytotoxicité sur la souche de cellules KB (carcinome de l’épiderme nasopharyngien humain) et sur la souche de cellules MRC5 (fibroblastes embryonnaires humains). Sept des treize composés ont montré une bonne activité antiplasmodiale avec des concentrations inhibitrices à 50% (CI50) inférieures à 5 µg/ml. Cependant, certains d’entres eux montrent en même temps une cytotoxicité significative, ce qui indiquerait que l’activité antiplasmodiale observée serait corrélée à leur activité cytotoxique.

Polychlorinated biphenyls (PCBs) were determined in sediments and two fish species collected from the Murchison Bay in Lake Victoria, using high resolution gas chromatography coupled to a high resolution mass spectrometer. Total PCB concentrations (Sigma(18)PCBs) varied widely with mean values ranging from 777 to 4325 pg g(-1)dry weight (dw) for sediments and 80 to 779 pg g(-1) wet weight (ww) for fish. The PCB levels in the sediments were significantly higher at the station closest to Nakivubo channel, presumably due to effluents discharged by the channel, which may contain domestically produced commercial PCB mixtures. For fish, the concentrations in Nile perch (Lates niloticus) were significantly greater than those in Nile tilapia (Oreochromis niloticus) at all study stations, possibly due to dietary differences among species. World Health Organization-toxic equivalents (WHO2005-TEQ5) for the dioxin-like PCBs were 0.04-0.64 pg g(-1), dw and 0.01-0.39 pg g(-1) ww for sediments and fish, respectively. The non-ortho PCBs exhibited the highest contribution to the Sigma(12)TEQs (>75%) compared to the mono-ortho PCBs in both fish species. The TEQs in the present study were lower than many reported worldwide in literature for fish and were within the permissible level recommended by the European Commission, implying that the fish did not pose health hazards related to PCBs to the consumers. (c) 2014 Elsevier B.V. All rights reserved.

Seven flavonols including the novel 3-(2″-acetylrhamnosides) of myricetin and quercetin ( 2 and 6 ), the rare kaempferol 3-(2″-acetylrhamnoside) and quercetin 3-(3″-acetylrhamnoside), in addition to the 3-rhamnosides of kaempferol, quercetin and were isolated from blue flowers of the African water lily Nymphaea caerulea (= Nymphaea capensis ). Their structures were elucidated by a combination of chromatography and homo- and heteronuclear two-dimensional NMR techniques and electrospray MS for compound 2 .

The analysis of anthocyanin pigments in the passion fruit Passiflora edulis and in the highly colored fruits of P. suberosa was performed using combinations of chromatographic and spectroscopic techniques. In addition to cyanidin 3-glucoside (97%), small amounts of cyanidin 3-(6″-malonylglucoside) (2%) and pelargonidin 3-glucoside (1%) were found in the rind of the passion fruit. The 3-(6″-malonylglucoside) and 3-glucoside of cyanidin, delphinidin, petunidin, and pelargonidin were identified in extracts of P. suberosa. Anthocyanins acylated with malonic acid constituted 27% of the total anthocyanin content in this latter species.

Graphical abstract Purple abaxial colouration of leaves of Hemigraphis colorata (Acanthaceae) is caused by two unusual anthocyanins., Highlights • Hemigraphis colorata leaves with purple abaxial colouration contain two anthocyanins. • The anthocyanins are based on the anthocyanidin 5-O-methylcyanidin. • This anthocyanidin has reduced numbers of possible quinoidal forms. • The major anthocyanin contains the unusual disaccharide 3-glucuronosylglucoside., The functional significance of anthocyanin colouration of lower (abaxial) leaf surfaces is not clear. Two anthocyanins, 5-O-methylcyanidin 3-O-(3″-(β-glucuronopyranosyl)-β-glucopyranoside) (1) and 5-O-methylcyanidin 3-O-β-glucopyranoside (2), were isolated from Hemigraphis colorata (Blume) (Acanthaceae) leaves with strong purple abaxial colouration (2.2 and 0.6 mg/g fr. wt., respectively). The glycosyl moiety of 1, the disaccharide 3″-(β-glucuronopyranosyl)-β-glucopyranoside), has previously been reported to occur only in a triterpenoid saponin, lindernioside A. The structural assignment of the aglycone of 1 and 2 is the first complete characterisation of a natural 7-hydroxy-5-methoxyanthocyanidin. Compared to nearly all naturally occurring anthocyanidins, the 5-O-methylation of this anthocyanidin limits the type of possible quinoidal forms of 1 and 2 to be those forms with keto-function in only their 7- and 4′-positions.

The flavonol, 3- O -(2- O-s -D-glucopyranosyl-6- O-a -L-rhamnopyranosyl- s -D-glucopyranoside), was isolated from Erythrina abyssinica Lamarck, an African plant widely used as folk remedies against malaria and syphilis. The structure was established on the basis of homo- and heteronuclear two-dimensional nuclear magnetic resonance techniques.

Surface sediments (60 cm) from the Napoleon Gulf and Thurston Bay on the northern shore of Lake Victoria were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs). Fifteen PCDD/Fs and eleven dl-PCBs were found in 75.5% of the samples. The maximum concentrations of PCDD/Fs and dl-PCBs were 44.1 and 136 pg g(-1) dry weight (dw), respectively. Octachlorodibenzo-p-dioxin was the predominant PCDD/F congener at the Napoleon Gulf and Thurston Bay area. Regarding the dl-PCBs, a variation in levels was observed between the mono-ortho PCBs and non-ortho PCBs, with the former having higher levels than the latter. The PCDD/F and dl-PCB levels, in the sediments of Napoleon Gulf, which is near urban centers and industrial areas were markedly higher (α ≤ 0.05) than those from the Thurston Bay, which is offshore, suggesting that human activities could be sources of the pollutants to the surrounding water resources. World Health Organization-toxic equivalency quotients (WHO-TEQs) lay in the range of 0.07-5.53 pg g(-1) dw for PCDD/Fs and 0.01-0.23 pg g(-1) dw for dl-PCBs. 23.1% of samples from the Napoleon Gulf had their results above the set WHOPCDD/Fs-TEQ value.

International audience; A new 10β-hydroxy-19-nor-cardenolide, named toxicarioside M (1), was isolated from the trunk bark of Antiaris toxicaria (Pers.) Lesch (Moraceae), along with six known cardenolides (convallatoxin (2), convallatoxol (3), convalloside (4), 3-O-ß-D-xylopyranosylstrophanthidin (5), glucostrophanthidin (6) and strophanthidin (7)). Their structures were elucidated on the basis of HR-MS(n) analysis, spectroscopic methods (IR, UV, 1D and 2D NMR) and by comparison with data reported in the literature. The cardenolides were evaluated for their cytotoxic activity against KB, HCT-116, SF-268, MCF-7, HL-60, PC-3 and MRC-5 cell lines.

Phytochemical investigations of blue plumbago ( Plumbago auriculata Poir. syn. Plumbago capensis Thunb.) flowers have led to the isolation of six new anthocyanins based on three new anthocyanidins with 5,7-dimethoxylated A-rings. Their structures were identified by 2D nuclear magnetic resonance and high-resolution mass spectrometry as the 3-O-β-galactopyranosides (1,2,4) and 3-O-α-rhamnopyranosides (3,5,6) of 5,7-dimethyldelphinidin, 5,7-dimethylpetunidin, and 5,7-dimethylmalvidin. Identification of 1-6 implies new structures for the previously reported anthocyanidins pulchellidin, europinidin, and capensinidin to be 5,7-dimethoxy-3,3',4',5'-tetrahydroxyflavylium, 5,7,3'-trimethoxy-3,4',5'-trihydroxyflavylium, and 5,7,3',5'-tetramethoxy-3,4'-dihydroxyflavylium cations, respectively. The anthocyanins (0.4 mg/g flowers) were accompanied by the dihydroflavonol taxifolin 3'-O-β-glucopyranoside (1.4 mg/g) and the flavonols 5-methylquercetin 3-O-α-rhamnopyranoside (8.8 mg/g) and 5-methylquercetin (0.4 mg/g). The anthocyanins 1-6 are the first reported natural anthocyanins with no free hydroxyl groups in their 5- and 7-positions on their A-rings. They have thus no possibility of forming the tautomeric quinonoidal bases (anhydrobases), which are related to the free hydroxyl groups in the 5- and 7-positions of previously reported anthocyanins. The genes behind the 5,7-dimethoxylated anthocyanins might be useful for making anthocyanins with special properties (colors, etc.).

International audience; ETHNOPHARMACOLOGICAL RELEVANCE: The study was done to establish medicinal plants used in the treatment of various diseases by the people in the Northern sector of Kibale National Park in western Uganda. It was also aimed at establishing the plant parts used and the mode of preparation of remedies. These plants create a basis for phytochemical evaluation which can lead to the discovery of biologically active compounds that can be used as starting materials in the development of new drugs targeting selected diseases such as malaria. MATERIALS AND METHODS: The required information was obtained using open interviews, semi-structured questionnaires, focus group discussions and transect walks. RESULTS: Different medicinal plants (131 species) distributed over 55 families were observed to be used by the local communities around the Northern sector of Kibale National Park. The plants as reported in this paper are used to treat 43 physical illnesses/diseases. The most used parts of the plants are the leaves. Water is the main medium used for the preparation of the remedies which are mostly administered orally. CONCLUSION: The people in the study area have a rich heritage of traditional plants that are used in the health care system to treat diseases. These medicinal plants have contributed significantly to several disease therapies. The most common diseases treated are malaria and cough, which are mostly treated by Vernonia amygdalina Del. and Albizia coriaria Welw. respectively. The main sources of medicinal plants include bush land, home gardens, grasslands, and the forest.

The reliability of sorption data for organic contaminants with low water solubility has generated great concern because of the variability in the literature of the soil-water partition coefficient (K(OC)) values for these compounds. In particular, sorption on container walls in aqueous systems when measuring the sorption coefficient, K(D) (used to calculate K(OC) values), for strongly hydrophobic compounds (SHOCs) is a potential source for discrepancies in the K(OC) values. In this study, we eliminated sorption on container walls when measuring sorption of three halogenated compounds (alpha-endosulfan, beta-endosulfan, and chlorpyrifos) using mixed solvents. Various mixtures of methanol and water were used. Sorption experiments were designed using polytetrafluoroethylene (Teflon)-lined centrifuge tubes and a high-performance liquid chromatography (HPLC) syringe. Solution sample analysis was performed using HPLC equipped with a UV diode array detector and C-18 column at a wavelength of 214 nm, with acetonitrile/water (80:20, v/v) as the mobile phase. The solvophobic model was used to calculate the percent recovery (% R(M)) in water of the test compounds. Our results show that there is considerable sorption on container walls for the three chemicals at volume fractions of methanol (f(c)0.4). The data show that, in aqueous systems, percent recoveries for alpha-endosulfan, beta-endosulfan, and chlorpyrifos are 48, 45, and 61, respectively. Thus, to generate reliable sorption data for alpha-endosulfan, beta-endosulfan, and chlorpyrifos and other SHOCs, experiments may be conducted using Teflon-lined centrifuge tubes and HPLC syringes at volume fractions of methanol (f(c)or= 0.5).

Four anthocyanins, cyanidin 3-O-(2''-(5'''-(E-p-coumaroyl)-beta-apiofuranosyl)-beta-xylopyranoside)-5-O-beta-glucopyranoside, cyanidin 3-O-(2''-(5'''-(E-p-coumaroyl)-beta-apiofuranosyl)-beta-xylopyranoside), cyanidin 3-O-(2''-(5'''-(E-caffeoyl)-beta-apiofuranosyl)-beta-xylopyranoside) and cyanidin 3-O-(2''-(5'''-(E-feroyl)-beta-apiofuranosyl)-beta-xylopyranoside) were isolated from leaves of African milk bush, (Synadenium grantii Hook, Euphorbiaceae) together with the known cyanidin 3-O-beta-xylopyranoside-5-O-beta-glucopyranoside and cyanidin 3-O-beta-xyloside. The four former pigments are the first reported anthocyanins containing the monosaccharide apiose, and the three 5'''-cinnamoyl derivative-2''-(beta-apiosyl)-beta-xyloside subunits have previously not been reported for any compound.

From the dichloromethane-methanol (1:1) extract of the seed pods of Derris trifoliata, a new flavanone derivative (S)-lupinifolin 4´-methyl ether was isolated. In addition, the known flavonoids lupinifolin and rotenone were identified. The structures were determined on the basis of spectroscopic evidence. Lupinfolin showed moderate in vitro antiplasmodial activity against the D6 (chloroquine-sensitive) and W2 (chloroquineresistant) strains of Plasmodium falciparum. The different parts of this plant showed larvicidal activities against Aedes aegypti and rotenoids were identified as the active principles.

Organochlorine (OC) residues were analysed in soil samples collected from Kihiihi sub-county, Kanungu District, which is located in south-western Uganda. Mabira Central Forest Reserve which is located in central Uganda was used as a reference site in this study. The samples were collected at 15-20 cm depths below the soil surface and extracted with organic solvents. The extracts were cleaned using florisil, and were analysed using a gas chromatograph (GC) equipped with an electron capture detector (ECD). The results were confirmed using a GC equipped with a mass spectrometer (MS). The levels of the OC residues in soil from Kihiihi sub-county varied from non-detectable (ND) to 59 microg kg(-1) dry weight. The frequencies of detection for p,p'-DDT, p,p'-DDE and p,p'-DDD in the total soil samples were 47%, 24% and 11%, respectively. The o,p'compounds were detected in the following frequencies: o,p'-DDT (23%), o,p'-DDE (19%) and o,p'-DDD (8%). The low p,p'-DDE/p,p'-DDT residue ratios (0.2-0.9) in Kihiihi samples suggest recent inputs of DDT in Kihiihi sub-county. The detection frequencies for dieldrin, endosulfan-alpha, -beta and -sulphate in the soil samples were 21%, 26%, 31% and 19%, respectively. Mabira Forest Reserve soils showed detection frequencies of p,p'-DDT (5%) and p,p'-DDE (9% of the soil samples), varying from ND to 9 microg kg(-1). Although the use of OCPs has been banned, our results show that they can still be detected in the environment. Their presence may be attributed to adulteration of pesticides which are not banned and also atmospheric deposition.

This paper presents results based on determination of residue levels of 1,1,1-trichloro-2,2-bis[p-chlorophenyl]ethane (DDT) and its metabolites in five fish species from Rwenshama landing site on Lake Edward, Uganda. The residue levels were analysed by using a GC-ECD and confirmed by GC-MS. The DDT residues detected in fish samples from Lake Edward were p,p'-DDT, o,p'-DDT, p,p'-DDE, o,p'-DDE, p,p'-DDD and o,p'-DDD. All the analysed samples of fish presented mean DDT residues ranging from non-detectable levels to 68 microg kg(-1) fresh weight. High levels of p,p'-DDT were detected in comparison to the metabolites (p,p'-DDE and p,p'-DDD). The detection of higher levels of p,p'-DDT than p,p'-DDE and p,p'-DDD, in most fish samples, suggests recent exposure of fish to DDT. Generally, most of the fish samples had residue levels below the maximum residue limits (MRL) recommended by FAO/WHO Codex Alimentarius Commission.

Three anthocyanins were isolated from the red flowers of chenille plant, Acalypha hispida Burm. (Euphorbiaceae) by a combination of chromatographic techniques. Their structures were elucidated mainly by homo- and heteronuclear nuclear magnetic resonance spectroscopy and electrospray mass spectrometry, and supported with complete assignments of 13C NMR resonances. The novel pigment, cyanidin 3-O-(2"-galloyl-6"-O-alpha-rhamnopyranosyl-beta-galactopyranoside) (5%), contains the disaccharide robinoside. The other anthocyanins were identified as cyanidin 3-O-(2"-galloyl-beta-galactopyranoside) (85%), and cyanidin 3-O-beta-galactopyranoside (5%). Anthocyanins acylated with gallic acid have previously been identified in species from the families Nymphaeaceae and Aceraceae, and tentatively in Abrus precatorius (Leguminosae).

Two new anthocyanins (1, 2) were isolated from the stem bark of the castor plant, Ricinus communis L. by a combination of chromatographic techniques. The structures of the compounds were elucidated, mainly by nuclear magnetic resonance spectroscopy and high-resolution electrospray mass spectrometry, to be cyanidin 3- O-β-xylopyranoside-5- O-β-glucopyranoside (1) (21%), and cyanidin 3- O-β-xylopyranoside-5- O-(6′”- O-malonyl-β-glucopyranoside) (2) (79%). In addition, cyanidin 3- O-β-xylopyranoside-5- O-(6′”- O-methylmalonate-β-glucopyranoside) (3), formed by methyl esterification of the malonyl unit of 2 during isolation and storage, was identified.

A variety of thiol and thion esters, including acetates and benzoates with n-butyl and β-phenethyl alkyl groups, have been studied by electron impact mass spectrometry. Several rearrangement ions were documented and their persistence in low voltage and field ion spectra demonstrated. Among the significant ions found in the rich thion spectra, the most general requires O to S rearrangement of the alkyl group and subsequent cleavage to yield acyl ions (CH3CO or PhCO). This process is more important in longer chain compounds than in the methyl and ethyl homologues studied previously.