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Fungal endophytes are regarded as inexhaustible sources of pharmaceuticals and agrochemicals with profound antibacterial, anticancer or antifungal activities. Diaporthe sp., an endophytic fungus residing in medicinal plant S. cordatum, showed a good antagonism against bacterial pathogens of beans; Pseudomonas syringae pv phaseolicola (Psp) and Xanthomonas axonopodis pv phaseoli (Xap), with zones of inhibitions of 14.00 ± 1.15 and 17.00 ± 0.58 mm against the test organisms respectively. Large scale fermentation of Diaporthe sp. was performed on rice media after which ultrasonic extraction on methanol was done to yield methanol crude extract. Methanol crude extract was then partitioned between hexane and ethyl acetate to yield their respective crude extracts. Ethyl acetate fraction of Diaporthe sp. yielded one new naphthalene derivative compound which was accorded IUPAC name as 3-methoxy-5-methylnaphthalene-1, 7-diol after series of purifications on column chromatography as well as preparative high-performance liquid chromatography (pHPLC). Structure determination of isolated compounds was performed on 1D and 2D Nuclear Magnetic Resonance (NMR) spectroscopy experiments as well as a mass spectrometer to affirm its molecular mass. The F3 that yielded compound 1 had palpable antibacterial activities against Psp and Xap, with corresponding Minimum Inhibitory Concentration (MIC) values of 2.50 mg/ml (7.00 ± 0.00 mm) and 1.25 mg/ml (7.67 ± 0.33 mm) against the tests organisms respectively. These slight MIC values are chiefly attributed to the presence of active secondary metabolites in the fungal extracts that act against the test pathogens. This has therefore confirmed that fungal endophytes and their extractives have desirable antibacterial activities hence can be used in the formulation of agrochemicals or used as bio-control agents in crop protection especially in common beans (Phaseolus vulgaris L). Key words: Endophytes, Diaporthe sp, bean bacterial pathogens.

Increase in prevalence of resistant microorganisms especially to synthetic drugs, has necessitated the need to search for new bioactive compounds having natural origin. Phytochemical investigation of Olea africana extracts afforded two triterpenoids namely erythrodiol and uvaol which were obtained through repeated column chromatography. The compounds were characterized using Nuclear Magnetic Resonance (NMR) spectroscopy and by comparison with literature values. The isolated triterpenoids exhibited moderate antibacterial activity whereas crude extracts exhibited relatively high antibacterial activity against Gram positive bacterial strains; methanol showed 12.4 mm zone of inhibition against Staphylococcus aureus, Erythrodiol exhibited higher antibacterial activity than uvaol against Gram positive bacteria S. aureus with zones of inhibition of 5.2 mm and 5.0 mm respectively. None of the pure compounds showed significant activity against Gram negative bacteria Escherichia coli. The results give a scientific validity and credence to the ethno-medicinal use of this medicinal plant as a chewing stick. Key words: Olea africana, triterpenoids, antibacterial activity.

Medicinal plants have always played a key part in health care. In fact, plants represent an enormous pool of new, undiscovered, and bioactive molecules. Therefore, ethnopharmacological and ethnobotanical studies are essential to discover new substances for the treatment of diseases. The Vernonia genus has about one thousand species and members of the genus are widely used as food and medicine. The plant-derived triterpenoids are commonly used for medicinal purposes in many countries, because they possess various pharmacological properties. A large number of triterpenoids are known to exhibit cytotoxicity against a variety of tumor cells as well as anticancer efficacy in preclinical animal models. Therefore this review presents an overview of Vernonia species with their biological potential, ethnomedicinal uses and the triterpenoids isolated from this genus. This will help to identify the state of ethnopharmacological knowledge in regard to this genus and to propose future research priorities.

The determination of retention efficiencies of halogenated and non-halogenated hydrocarbon in selected wetland ecosystems in Lake Victoria basin was carried out. Qualitative and quantitative determination of the presence of residual hydrocarbons in Kigwal/Kimondi, Nyando and Nzoia wetland ecosystems using Gas Chromatography - Mass Spectrometer (GC-MS) instrument indicated the presence of residual organochlorines, organophosphorus, carbamates and synthetic pyrethroid hydrocarbons in water, sediment and plant materials. In order to compare the retention efficiencies of the wetlands, the wetland ecosystems were divided into three different sections, namely: inlet, mid and outlet. Calculations of mass balances of residual halogenated and non-halogenated hydrocarbons at the respective sections was done taking into account the partition of the studied compounds in samples of water, sediments and papyrus reed plant materials and analyzed using validated Gas Chromatography - Mass Spectrometer (GC-MS) method. From the analysis, several residual hydrocarbons namely: bendiocarb, benzene hexachloride (BHC), carbaryl, cypermethrin, decis, deltamethrin, diazinon, dieldrin, DDT, DDD, DDE, malathion, propoxur, sumithion, 5-phenylrhodanine, 1,3,5-trichlorobenzene, 1-(2-phenoxybenzyl)hydrazine were detected and quantified. The levels of the selected residual hydrocarbons in water samples were used to calculate the retention efficiencies of a specific hydrocarbon and the values recorded. Generally, River Nyando wetland recorded mean percentage retention efficiencies of 76 and 94% for dry and rainy seasons respectively; Kigwal/Kimondi wetland had seasonal mean percentage retention efficiencies of 63 to 78%. River Nzoia also had calculated seasonal mean percentage retention efficiencies of between 56 to 88%. Dry season had lower mean percentages retention efficiencies as compared to rainy season in the three wetlands of interest during the period of study. The study observed that retention efficiencies of tropical wetland ecosystems is greatly affected by its concentration within the wetland tank systems, anthropogenic activities, physical properties of the hydrocarbon, and environmental conditions among others. There are several anthropogenic activities which contributed to the presence of hydrocarbons in the wetlands and they included: agricultural, municipal, industrial and public health activities. DOI: http://dx.doi.org/10.3126/ije.v4i2.12623 International Journal of Environment Vol.4(2) 2015: 38-52

Pupae are an integral part of Anopheles gambiae life history and a tool that effectively targets them is likely to impact on malaria vector density. In this study we evaluated pupicidal activities of crude ethanol and water extracts of Phytolacca dodecandra (L’ Herit) on An. gambiae (Diptera: Culicidae) under laboratory condition. Individual early pupae of An. gambiae mosquitoes were exposed to concentrations of 40, 20, 10, 5, 2.5 mgs/100 ml of mature green fruits and leaves of the shoot and midsection of P. dodecandra in containers measuring 6 cm top × 5.7 cm bottom × 3.5 cm height. P. dodecandra was sourced from Eldoret (highland) and Nyando (lowland). Extraction of P. dodecandra bioactives was done using 80% ethanol and distilled water. Extracts of Neem leaves and untreated rain water were used as positive and negative controls respectively. WHO, 2005 mortality threshold of >80% was used to determine the effectiveness of the extracts as pupicide 24 hours post exposure. Mortality of exposed pupae was dose dependent. Concentrations of 20 mgs/100 mls and higher and 40 mgs/ 100mls of mature green fruits from Nyando and Eldoret met the mortality threshold respectively. Extracts of P. dodecandra from Nyando was more potent than that from Eldoret as was water compared to ethanol extracts. Positive (Neem) control killed < 80% of exposed pupae. It was concluded that crude extracts of P. dodecandra are potent as pupicide against An. gambiae mosquitoes and is a likely alternative to synthetic insecticides against An. gambiae in future.

A prenylated cinnamaldehyde (glomeral), together with the known p -hydroxycinnamic acid, caffeic acid, methyl cinnamate, hesperetin, scoparone, skimmianine, syringaresinol and two limonoids (limonin and limonyl acetate) were isolated from the roots and stem bark of Vepris glomerata . The antibacterial assay of the isolated compounds indicated an inhibition zone, ranging from 8 to 16 mm, against standard strains of Staphylococcus aureus (ATCC 29213, 25923) and Shigella dysentrieae . Glomeral inhibited the growth of S. aureus and S. dysentrieae at low concentrations (MIC of 2 μg/mL and 0.4 μg/mL respectively). Of the other compounds tested, hesperetin displayed good antibacterial activity, the limonoids, scoparone and skimmianine displayed moderate antibacterial activity and the cinnamic acid derivatives were inactive against the test pathogens. This study provides a rationale for the use of V. glomerata in its treatment of bacterial infections.

The essential oil of Tarchonanthus camphoratus (Asteraceae), obtained by hydro-distillation, was analysed by gas chromatography–mass spectrometry (GC–MS) and also evaluated for antimicrobial activity. Out of 45 peaks representing 99.8% of the oil, 38 components which constitute 95.8% of the total oil were identified. The oil was dominated by monoterpenes, which accounted for 80.9% of the oil. This study indicates the presence of a high percentage of oxygenated monoterpenes (62.3%), of which the main constituents were fenchol (15.9%), 1,8-cineole (14.3%) and α-terpineol (13.2%). Other monoterpenes present in fairly good amounts were α-pinene (6.87%), trans-pinene hydrate (6.51%), terpinen-4-ol (4.74%) and camphene (3.76%). The oil was screened for antimicrobial activity against both Gram positive (Staphylococcus aureus, Bacillus ssp.) and Gram negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Klebsiella pneumoniae, Proteus mirabilis) bacteria and a pathogenic fungus Candida albicans. Except for P. aeruginosa, which showed resistance, the oil had pronounced antibacterial and antifungal activities.

Calpurnia aurea is an African medicinal plant used in many countries in Africa to treat a range of medical conditions or disorders. Extracts of the plant were shown to be active in antibacterial and antioxidant assays as well as against lice, ticks and maggots. The aim of the study was to isolate the phytochemical constituents from the plant and to test them in appropriate bioassays dependent on the compounds isolated in order to provide a rationale for the use of the plant in ethno-medicine or to provide some information on its constituents.The stem and bark of the plant was extracted with organic solvents of varying polarity and the extracts separated and purified using column chromatography. The isolated compounds were identified by NMR spectroscopy and the compounds were tested for their in vitro anticancer activity against breast (MCF7), renal (TK10) and melanoma (UACC62) human cell lines using an in house method developed at the CSIR, South Africa.The isoflavones, 4',5,7-trihydroxyisoflavone (1), 7,3'-dihydroxy-5'-methoxyisoflavone (2), 7-hydroxy-4',8-dimethoxyisoflavone (3), 7-acetoxy-4',8-dimethoxyisoflavone (4) and 3',7-dihydroxy-4',8-dimethoxyisoflavone (5), a pterocarpan (3-acetoxy-9-methoxypterocarpan) and a quinolizidine alkaloid (calpurnine) were isolated from the stem and bark of Calpurnia aurea. The tetrasubstituted isoflavone 5 was found to be the most active in the three cell lines amongst all the compounds tested. This was followed by trisubstituted isoflavone 2.The isoflavones showed moderate activity against the renal, melanoma and breast cancer cell lines tested against, with the isoflavones 2 and 5 showing the best activity of the compounds tested. These isoflavones may have a synergistic effect with other anticancer drugs.

Antioxidants activities from plants sources have attracted a wide range of interest across the world in recent times. This is due to growing concern for safe and alternative sources of antioxidants. The free radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), reducing power assay, total antioxidant capacity of the phosphomolybdenum method and the total phenolics content using the Folin-Ciocalteu reagent were carried out on the acetone, n-butanol and methanol root extracts of Anchomanes difformis. The results of the total phenolics content expressed in mg/100 g of gallic acid equivalent (GAE) showed that the n-butanol extract has significantly (p0.05) higher phenolics content (381 +/- 1.13) than the methanol and acetone extracts. All the extracts displayed strong concentration dependent radical scavenging activity. It was also observed that the n-butanol extract showed higher activity of 70.87% and 78.59% at low concentrations of 31.25 microg/mL and 62.5 microg/mL, respectively, than methanol and acetone extracts. The results also showed that the n-butanol extract has strongest reducing ability which is comparable to that of gallic acid at all the concentrations tested. Phytochemical screening on the extracts revealed the presence of flavonoids, saponins, and tannins. The results suggest that n-butanol extract of the plant is very rich in antioxidant compounds worthy of further investigations.

Three novel quinolizidine alkaloids, N-methylenehydroxycytisine (1), 6,7-dihydroxylupanine (2), and velutinine (3) have been isolated from the fruits and pods (1 and 2) and stem bark (3) of Sophora velutina subsp. zimbabweensis along with the known quinolizidine alkaloids, 7-hydroxylupanine (4), thermopsine (5), N-methylcytisine (6), cytisine (7), an aromatic ester, methyl-3-(3',4'-dimethoxyphenyl)-2-propenoate (8) and the triterpenoids, lup-20(29)-ene-3beta-ol (9) and 12-oleanen-3-one (10). Compounds 6 and 10 showed good antibacterial activity against E. faecalis, with MIC values of 20.8 and 10.9 microg mL(-1), respectively. The other compounds tested exhibited low to moderate antibacterial activity.

Two A-seco-limonoids, accorded the trivial names, uguenensene and uguenensone and a C-7 prenylated flavonoid, uguenenprenol were isolated from Vepris uguenensis (Rutaceae). In addition, 11 known compounds, niloticin, chisocheton A, kihadalactone A, limonyl acetate, methyl uguenenoate, 7-O-methylaromadenrin, flindersiamine, 8α,11-elemodiol, tricoccin S₁₃ acetate, skimmianine, and lupeol were isolated. The structures of the compounds were elucidated and characterized by spectroscopic analyses (NMR, GC-MS and IR). Antioxidant activity of the isolated compounds showed that uguenenprenol and 7-O-methylaromadenrin are good antioxidant agents. Significantly high antioxidant activity was also exhibited by 8α,11-elemodiol, which was 72% at 250 μg mL⁻¹ and 57% at 15.62 μg mL⁻¹ when tested with the deoxyribose method. The two liminoids fit nicely into the biosynthetic pathway from niloticin to methyl uguenenoate.

The dichloromethane extract of the aerial part of the plant Vepris glomerata (Rutaceae) yielded a new flavonoid, which was accorded the trivial name veprisinol (1), together with four known furoquinoline alkaloids: haplopine-3,3'-dimethylallyl ether (2), anhydroevoxine (3), evoxine (4) and skimmianine (5). The structures of the compounds were established by 1D and 2D NMR spectroscopy, as well as HREIMS. Compounds 1 and 2 have strong antioxidant potential, similar to and in some instances better than ascorbic acid and can be used as beneficial additives to antioxidant supplements.

The present study was conducted to examine the anti-oxidative activities of extracts from different parts of Ziziphus mucronata. Stem bark, root and leaf samples were sequentially extracted with solvents of increasing polarity and tested for in vitro anti-oxidative activity using various models. Our results indicated that all the extracts had potent electron donating and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activities. However, the ethanolic extracts exhibited a significantly (p

Hydro-distilled essential oil from Satureja biflora (Lamiaceae) growing in Kenya was analysed by gas chromatography mass spectrometry (GC-MS) and also evaluated for antimicrobial activity. Twenty two compounds which constitute 99.29 % of the total oil were identified. The oil was dominated by monoterpenes, which accounted for 62.02 % of the oil. This monoterpene fraction was characterized by a high percentage of linalool (50.60 %) such that this Satureja species can be classified as the linalool chemotype. The other major monoterpenes were α-terpineol (2.80 %), β-ocimene (2.25 %), β-pinene (1.96 %) and cis -linalool oxide (1.91 %). Sesquiterpenes present in fairly good amounts are germacrene D (10.63 %), α-cadinol (4.53 %), β-bourbonene (2.33 %), δ-cadinene (2.19 %), τ-cadinol (2.17 %), endo-1-bourbonanol (2.14 %) and β-caryophyllene (1.98 %). Aliphatic alcohols and acids accounted for 7.23 % of the oil, of which the major one was linoleic acid (4.48 %). The oil was screened for antimicrobial activity against both gram-positive ( Staphylococcus aureus, Bacillus ssp. ) and gram-negative ( Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Klebsiella pheumoniae, Proteus mirabilis ) bacteria and a pathogenic fungus ( Candida albicans ). To the best of our knowledge nothing concerning the chemical composition and biological activity of the essential oil of S. biflora has been reported. KEY WORDS : Satureja biflora , Essential oil, Antimicrobial activity Bull. Chem. Soc. Ethiop. 2007 , 21(2), 249-254.

Background: Calpurnia aurea is an African medicinal plant used in many countries in Africa to treat a range of medical conditions or disorders. Extracts of the plant were shown to be active in antibacterial and antioxidant assays as well as against lice, ticks and maggots. The aim of the study was to isolate the phytochemical constituents from the plant and to test them in appropriate bioassays dependent on the compounds isolated in order to provide a rationale for the use of the plant in ethno-medicine or to provide some information on its constituents. Materials and methods: The stem and bark of the plant was extracted with organic solvents of varying polarity and the extracts separated and purified using column chromatography. The isolated compounds were identified by NMR spectroscopy and the compounds were tested for their in vitro anticancer activity against breast (MCF7), renal (TK10) and melanoma (UACC62) human cell lines using an in house method developed at the CSIR, South Africa. Results: The isoflavones, 4′,5,7-trihydroxyisoflavone (1), 7,3′-dihydroxy-5′-methoxyisoflavone (2), 7-hydroxy-4′,8-dimethoxyisoflavone (3), 7-acetoxy-4′,8-dimethoxyisoflavone (4) and 3',7-dihydroxy-4′,8-dimethoxyisoflavone (5), a pterocarpan (3-acetoxy-9-methoxypterocarpan) and a quinolizidine alkaloid (calpurnine) were isolated from the stem and bark of Calpurnia aurea. The tetrasubstituted isoflavone 5 was found to be the most active in the three cell lines amongst all the compounds tested. This was followed by trisubstituted isoflavone 2. Conclusion: The isoflavones showed moderate activity against the renal, melanoma and breast cancer cell lines tested against, with the isoflavones 2 and 5 showing the best activity of the compounds tested. These isoflavones may have a synergistic effect with other anticancer drugs.

Three novel quinolizidine alkaloids, N-methylenehydroxycytisine (1), 6,7-dihydroxylupanine (2), and velutinine (3) have been isolated from the fruits and pods (1 and 2) and stem bark (3) of Sophora velutina subsp. zimbabweensis along with the known quinolizidine alkaloids, 7-hydroxylupanine (4), thermopsine (5), N-methylcytisine (6), cytisine (7), an aromatic ester, methyl-3-(3′,4′-dimethoxyphenyl)-2-propenoate (8) and the triterpenoids, lup-20(29)-ene-3β-ol (9) and 12-oleanen-3-one (10). Compounds 6 and 10 showed good antibacterial activity against E. faecalis, with MIC values of 20.8 and 10.9 μg mL−1, respectively. The other compounds tested exhibited low to moderate antibacterial activity.