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Aim: The aim of this study was to compare the texture, mineral element and heavy metal content of the soil under the litter of different selected species in relation to the plan of their pedogenesis. Methods: The granulometric analysis of the various samples based on laser diffraction, measurements of Total Nitrogen and Total Organic Carbon were performed using the Elemental Analyzer, the Organic Matter content is estimated by the loss of ignition method using a Salvis furnace, In order to estimate the CaCO3 content. The same samples were heated in the oven at 1000°C for 60 minutes and reweighed. The carbonate content is estimated by the loss in mass during this second firing, multiplied by 2.274 which is the molecular weight ratio between CaCO3 and CO2. The heavy metal and mineral composition was evaluated by ICP-AES and AAS. Results: The granulometric analyses show a sandy texture, according to the FAO classification. The organic matter content thus observed in the soils under the litter of these four species did not show any significant difference. The concentration of major mineral elements recorded in soils under the litter of Blighia welwitchii, Oncoba welwitschii, Zanthoxylum gilletii and Harungana madagascariensis did not show any significant difference. However, potassium, phosphorus, and magnesium have a high concentration compared to calcium and sodium. This study showed that the levels of cadmium, lead, arsenic and aluminum in the various samples of litter soils of all plant species including nickel for B. welwitschii are above the standards set by the Canadian Council of Ministers of the Environment for soil quality. Pollution factors for aluminum are the highest. This indicates that aluminum is the most polluting metal. The low pollution factors for lead and nickel are due to the low fixation of these metals by soils. Conclusions: Our study took place in the Luki Biosphere reserve and showed that the different soils under litter are polluted by very toxic and persistent heavy metals such as cadmium, lead, aluminum, arsenic and nickel. This study has revealed new aspects of heavy metal pollution. This pollution represents a serious threat to the environment in general and to humans in particular through the food chain.

Rural communities in Kenya largely depend on plant resources for their livelihood. The utilization of these resources depends on the availability of plant resources and the level of knowledge of the residents. We conducted an ethnobotanical study in Tharaka-Nithi County in Kenya to determine the knowledge and utilization of various plant species by the local communities. The study was conducted in four major administrative regions from June 2018 to February 2019, involving interview schedules using semi-structured open-ended questionnaires and guided field collections with 48 informants. A total of 214 plant species distributed in 73 families and 169 genera with 616 Use Reports (URs) were documented. Fabaceae was the highest family cited by the informants (31 species) followed by Lamiaceae and Euphorbiaceae (each with 11 species). Trees (49%) and shrubs (32%) were the top life forms of the plants frequently utilized by the local residents. The general plant uses reported were medicinal, food, fodder, construction, fuel, pesticidal, religious, live fencing, and making crafts. Zanthoxylum gilletii, Prunus africana, and Solanum incanum were found to be highly valued by the local communities. Plant utilization as food and medicinal uses against snake-bite related problems had the highest Informant Consensus Factor (ICF). Only 29 (13.6%) of the species reported had their status assessed by the International Union for Conservation of Nature (IUCN). Conservation measures, alongside awareness creation in this region, are highly recommended for the species endemic to the region, highly depended on by the community, and those threatened according to IUCN standards.

Zanthoxylum gilletii (De Wild.) P.G.Waterman — Habit: Tree. Habitat: LMWF; up to 2 400 m. Distribution: II. Voucher: Chogoria Track, Alt. 1 860 m, 28 Jan. 2015, SAJIT 002977 (HIB). References: Kokwaro (1982), Bussmann (1993, 1994), Bussmann & Beck (1995a, 1999)., Published as part of Zhou, Ya-Dong, Mwachala, Geoffrey, Hu, Guang-Wan & Wang, Qing-Feng, 2022, Annotated checklist of the vascular plants of Mount Kenya, East Africa, pp. 1-108 in Phytotaxa 546 (1) on page 61, DOI: 10.11646/phytotaxa.546.1.1, http://zenodo.org/record/6550464, {"references":["Kokwaro, J. O. (1982) Rutaceae. In: Polhill, R. M. (Ed.) Flora of Tropical East Africa. A. A. Balkema, Rotterdam, 52 pp.","Bussmann, R. W. (1993) The forest of Mt. Kenya (Kenya): A phytosociological approach with special reference to ecological problems. Ph. D. Thesis, Eberhard Karls Universitat Tubingen, Tubingen, 119 pp.","Bussmann, R. W. (1994) The forest of Mt. Kenya (Kenya): Vegetation, ecology, destruction and management of a tropical mountain forest ecosystem. Ph. D. dissertation, Universitat Bayreuth Startseite, Bayreuth, 252 pp.","Bussmann, R. W. & Beck, E. (1995 a) The forests of Mt. Kenya (Kenya), a phytosociological synopsis. Phytocoenologia 25 (4): 467 - 560. https: // doi. org / 10.1127 / phyto / 25 / 1995 / 467","Bussmann, R. W. & Beck, E. (1999) Vegetation units of Mt. Kenya Forest Reserve: Comment. In: Bitok (Ed.) Vegetations-okologosche, ethnobotanische und faunistische Beitrage uber Aquatorial-Afrika. Bayreuther Forum Okologie 64. Bayreuther Forum Okologie, Bayreuth, pp. 17 - 28."]}

Soils account for >80% and 20% of the total agricultural N2O and CO2 emissions respectively. Soil management activities that target improved soil health, such as enhancing earthworm activity, may also stimulate further emissions of CO2 and N2O. One recommended strategy for mitigating these soil emissions is biochar amendment. However greater clarity on the interaction between earthworm activity and biochar, and subsequent impact on CO2 and N2O are needed to evaluate the environmental impacts of management practice. We measured N2O and CO2 emissions from a kaolinitic Acrisol in the presence or absence of earthworms, with and without application of two different biochars in a microcosm study. The two biochars were derived from indigenous trees; Zanthoxylum gilletii and Croton megalocarpus, and were tested at three application rates of 5 Mg ha−1, 10 Mg ha−1 and 25 Mg ha−1. Emissions of CO2 and N2O increased by 26% and 72% respectively in the presence of earthworms. In microcosms with biochar and earthworms however, emissions depended on type of biochar and rate of application. With C. megalocarpus, CO2 emission increased with increasing rates of biochar application with 25 Mg ha−1 resulting in higher CO2 fluxes compared to no-biochar control (p = 0.002), while no change was observed with Z. gilletii at the same rate. Nitrous oxide emissions were suppressed at 25 Mg ha−1 for both C. megalocarpus (p = 0.009) and Z. gilletii (p = 0.011). Reduction in N2O flux was however not consistent across biochar types. No change in N2O was observed with 5 Mg ha−1 and 10 Mg ha−1of C. megalocarpus. Biochar from Z. gilletii at 5 Mg ha−1 however led to increase in N2O emissions (p

Antibacterial activity of extracts of Zanthoxylum gilletii, Markhamia lutea and their fungal endophytes were evaluated against bacterial pathogens of common bean: Xanthomonus axonopodis pv. phaseoli and Pseudomonus syringae pv. phaseolicola. The leaves of both plants were dried under shade, ground to fine powder and extracted using methanol. The methanol extracts were fractionated sequentially using ethylacetate and hexane to produce various fractions. Endophytic fungi were isolated from fresh leaves and identified by ITS-rDNA sequence analysis. Antibacterial screening of the fungal endophytes was done by dual culture assay. The most active endophytic fungi were fermented on rice media and extracted using methanol. Pure compounds were analyzed by a combination of mass spectrometry and spectroscopic techniques which included 1D and 2D NMR. Antibacterial activity of all the extracts was determined by disc agar diffusion assay against the test organisms. Twenty-four (24) fungal endophytes were isolated which included: Fusarium, Chaetomium, Scopulariopsis and Trametes. Endophytic Fusarium solani was the most active against X. axonopodis pv. phaseoli (20.3 mm inhibition zone) and P. syringae pv. phaseolicola (18.6 mm inhibition zone). The plant extracts were active against X. axonopodis pv. phaseoli with an inhibition zone ranging between 8-12 mm except the methanol extract from Z. gilletii which did not show any activity. The endophytic extracts were active against both test organisms with a zone of inhibition ranging from 9.3-14 mm. Phenolic compounds present in Fusarium species may have contributed to the antibacterial activity of this strain against the test organisms. Key words: Common bean, medicinal plants, fungal endophytes, antibacterial activity, Xanthomonus axonopodis pv phaseoli, Pseudomonus syringae pv phaseolicola.

The charcoal sector constitutes an important source of employment and revenue for many tropical agroecosystems. Better understanding of the effects of charcoal-making is thus warranted to guide actions aimed at minimising environmental externalities. Conversion of trees to charcoal eliminates canopy effects associated with the living trees while at the same time creates new conditions in and around spots where the charcoal is produced due to increased concentration of pyrogenic organic matter (PyOM). It is unclear, whether such unintentional PyOM additions play a role in the abundance and distribution patterns of soil macrofauna. A study was conducted in South Nandi (Kenya) to assess effects of PyOM on soil macrofauna, taking advantage of abandoned traditional earth-mound charcoal kilns, where Croton megalocarpus Hutch. and Zanthoxylum gilletii (De Wild.) P.G.Waterman trees were used in charcoal making. Soil and soil macrofauna samples were collected at increasing distances from the centre of the spots. Total C, non-pyrogenic C (non-PyC) and total N progressively increased with increasing distance from the centre of the spots, whereas soil pH, pyrogenic C (PyC), available P and exchangeable K decreased. The number of earthworms and centipedes in Z. gilletii spots (119 and 14 individuals m−2, respectively) was twice as high as in kilns where C. megalocarpus was used. Notably, while the number of earthworms in spots rich in Z. gilletii PyOM significantly increased with increasing distance from the centre of the spots, the opposite trend was observed for centipedes. In contrast, no significant differences in the spatial distribution of earthworms or centipedes were found in spots rich in C. megalocarpus PyOM. Furthermore, beetles, termites and crickets were significantly higher in C. megalocarpus than Z. gilletii spots, but sampling distance also had no significant influence. As hypothesised, source of PyOM played a major role in determining soil properties and macrofauna distribution patterns thus showing the value of abandoned charcoal-making spots in contributing to a mosaic of soil conditions that could ultimately affect soil productivity in tropical agricultural systems.

Africa is famous for its floral biodiversity, exploited by local people for therapeutic purposes. However, such plants need to be scrutinised scientifically for the presence of bioactive compounds and possible biological properties. This study attempts for the first time to highlight the pharmacological and phytochemical profile of extracts prepared from leaves and stem barks of three African plants (Macaranga hurifolia Beille, Sterculia tragacantha Lindl. and Zanthoxylum gilletii (De Wild.) P. G. Waterman. The extracts were tested for antioxidant and enzyme inhibitory effects. Free radical scavenging, metal chelator, reducing power and phosphomolybdenum assays were performed to evaluate antioxidant effects. To identify enzyme inhibitory effects, cholinesterases (acetylcholinesterase (AChE) and butrylcholinesterase (BChE)), tyrosinase, α-amylase and α-glucosidase were selected as target enzymes. High performance liquid chromatography-Electrospray tandem mass spectrometry (HPLC-ESI-MS) technique was also used for chemical profiling. ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assays showed that the stem barks of all three African plants were better scavenger than leaf extracts. Sterculia tragacantha was found to be a better metal chelator (64.10 ± 4.66 mg EDTAE/g) among the studied plants. All extracts exhibited good clinical enzyme inhibitory activities. The stem bark of S. tragacantha exhibited the best acetylcholinesterase activity compared to the other plants. HPLC-ESI-MS characterization showed that the most abundant compounds in stem bark were flavonoids in M. hurifolia (4.2 ± 0.2 mg/g DE), proanthocyanidins in S. tragacantha (42 ± 1 mg/g DE) and similar concentrations of phenolic acids and flavonoids in Z. gilletii (2.8–3.1 mg/g DE). Based on the biological activity, the most abundant and relevant bioactive compounds in the extracts were studied using molecular modelling approach against tyrosinase. The studied African plants showed good antioxidant and enzymatic propensities and thus can be considered as potential bioresources for future development of nutraceuticals and/or for pharmaceutical applications.

Soil organic matter (SOM) is considered an important determinant of soil fertility in tropical agroecosystems. While numerous studies have shown the value of agroforestry in increasing soil nutrients and improving crop yield, few have addressed the systematic impacts of duration of cultivation on soil aggregation and C storage in such systems. A study was conducted in South Nandi (Kenya) to assess spatial influence of three dominant trees (Croton megalocarpus, Eucalyptus grandis and Zanthoxylum gilletii) on soil aggregation and C content in agroforestry systems. The study was conducted in a chronosequence experimental set-up where farms were continuously cultivated for 10, 16 and 62 years since conversion from primary forest. It was hypothesized that soil aggregates and whole soil and aggregate-associated C would decrease with duration of cultivation, with the magnitude of influence being reduced by the presence of trees and abundance of earthworms and termites. Greater abundance of small macroaggregates and microaggregates were recorded in soils under the canopy of Z. gilletii with an average weight of 62.8 g and 9.4 g 100 g−1 of soil compared to 53.9 g and 3.1 g 100 g−1 in soils under C. megalocarpus and 48.7 g and 3.9 g 100 g−1 in soils under E. grandis, respectively. These differences could be attributed to the high number of endogeic earthworm species, Nematogenia lacuum (Ocnerodrilidae) in soils under the canopy of Z. gilletii trees. Since N. lacuum is a small-sized species (40–55 mm long), it produces small faecal pellets and thus, we could infer that this species may have contributed to the fragmentation of large macroaggregates into small macroaggregates and microaggregates. The C content decreased by almost 40% in soils under longer duration of cultivation, with higher magnitude of differences associated with Z. gilletii trees. Increased microbial population in earthworms’ casts can increase mineralization rates, which may explain the low aggregate-associated C content under Z. gilletii trees where high number of N. lacuum were recorded. This study shows the significance of specific trees in shaping soil aggregation process and soil C content which could have far-reaching implications for the long-term C storage in the soil and hence net contributions to climate change mitigation.

The small Guineo-Congolian tree Alchornea cordifolia (Euphorbiaceae) has been observed to dominate the undergrowth in an open type of southwest Ethiopian riverine forest not recorded before. The nearest previously known records of this species were at the South Sudan–Congo border and in Uganda and Kenya near Lake Victoria. The newly discovered range extension of A. cordifolia matches that recently discovered for Zanthoxylum gilletii De Wild. (Rutaceae), found as new to Ethiopia in 2006, and is found to be congruent with previous known disjunct distributions of Guineo-Congolian-Ethiopian species. A new account of the genus Alchornea in Ethiopia, including A. cordifolia, is provided in the format of the Flora of Ethiopia and Eritrea.

Zanthoxylum gilletii is an African indigenous deciduous tree which is important for its medicinal use in many communities to treat a wide range of ailments. This study was conducted to identify the alkaloids present in the bark, root and leaves of the Kenyan Z. gilletii. The plant materials were randomly sampled, dried at room temperature, powdered and subjected to thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC-MS) analyses for the alkaloid confirmatory tests. The bark, root and leaf extract contained peroxysimulenoline, sanguinarine, fagarine I, norchelerythrine (dihydroavicine or demethylnitidine), trans-fagaramide, 8-methylnorchelerythrine and dihydronitidine alkaloids. The distribution of the alkaloids appeared to be quite variable within different plant parts and different regions. The identified alkaloids have been documented to be useful for their medicinal value in humans and also protect the plants against predation. The medicinal value of Z. gilletii may be due to its contents of varied alkaloids. The information on alkaloidal variation in the species has potential value and practical applications in chemotaxonomy, toxicology and pharmacognosy. The present findings may be useful in optimizing the processing and wild-harvesting of these alkaloids. Key words: Zanthoxylum gilletii, chemotaxonomy, pharmacognosy, liquid chromatography-mass spectrometry.

Ethnopharmacological relevance Plants from Kenyan flora are traditionally used against many ailments, including cancer and related diseases. Cancer is characterized as a condition with complex signs and symptoms. Recently there are recommendations that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants that treat cancer. Aim The present study was aimed at investigating the cytotoxicity of a plethora of 145 plant parts from 91 medicinal plants, most of which are used in the management of cancer and related diseases by different communities in Kenya, against CCRF-CEM leukemia cell line. Materials and methods Extracts from different plant parts (leaves, stems, stem bark, roots, root barks, aerial parts and whole herb) were obtained by cold percolation using different solvent systems, such as (1:1 v/v) dichloromethane (CH2Cl2) and n-hexane (1), methanol (MeOH) and CH2Cl2 (2); neat MeOH (3), 5% H2O in MeOH (4) and with ethanol (EtOH, 5); their cytotoxicities were determined using the resazurin reduction assay against CCRF-CEM cells. Results At a single concentration of 10 μg/mL, 12 out of 145 extracts exhibited more than 50% cell inhibition. These include samples from the root bark of Erythrina sacleuxii (extracted with 50% n-hexane-CH2Cl2), the leaves of Albizia gummifera, and Strychnos usambarensis, the stem bark of Zanthoxylum gilletii, Bridelia micrantha, Croton sylvaticus, and Albizia schimperiana; the root bark of Erythrina burttii and E. sacleuxii (extracted with 50% CH2Cl2–MeOH), the stem bark of B. micrantha and Z. gilletii (extracted using 5% MeOH–H2O) and from the berries of Solanum aculeastrum (extracted with neat EtOH). The EtOH extract of the berries of S. aculeastrum and A. schimperiana stem bark extract displayed the highest cytotoxicity towards leukemia CCRF-CEM cells, with IC50 values of 1.36 and 2.97 µg/mL, respectively. Other extracts having good activities included the extracts of the stem barks of Z. gilletii and B. micrantha and leaves of S. usambarensis with IC50 values of 9.04, 9.43 and 11.09 µg/mL, respectively. Conclusions The results of this study provided information related to the possible use of some Kenyam medicinal plants, and mostly S. aculeastrum, A. schimperiana, C. sylvaticus, Z. gilletii, B. micrantha and S. usambarensis in the treatment of leukemia. The reported data helped to authenticate the claimed traditional use of these plants. However, most plants are used in combination as traditional herbal concoctions. Hence, the cytotoxicity of corresponding plant combinations should be tested in vitro to authenticate the traditional medical practitioners actual practices.

Malaria is a serious health problem in many African countries. The Anopheles gambiae mosquito which is the major vector for this disease has developed resistance against synthetic pyrethroids which are the main stay of insecticide treated bed nets. The development of insecticide resistance and side effects associated with synthetic pesticides has triggered intense research efforts towards natural products (for vector control) such as essential oils because of their efficacy and safety. In this study, larvicidal potential of essential oil from Zanthoxylum gilletii was evaluated against malaria vector mosquito, A. gambiae . The essential oil was extracted by hydro-distillation, and its chemical compositions determined by gas chromatography mass spectrometry. The oil was dominated by sesquiterpenes and monoterpenes which accounted for 38.30 and 34.00%, respectively. The oil showed good activity against A. gambiae and recorded LC 50 and LC 90 values of 57.73 and 140.24 ×10 -3 mg/ml, respectively. The results obtained show that the essential oil isolated from Z. gilletii is a promising mosquito larvicide. Keywords: Malaria, Zanthoxylum gilletii , essential oil, Anopheles gambiae , larvicidal activity African Journal of Biotechnology, Vol 13(21) 2175-2180

International audience; L’analyse UPLC-MS/MS de l’extrait brut hydroacétonique des feuilles de Zanthoxylum gilletii a permis l’identification de composés phénoliques tels l’acide gallique et dérivés (9,40 mg EAG/g ms), l’acide protocatéchique (0,22 mg EAP/g ms), des flavonoïdes (6,34 mg EQ/g ms) et des acides hydroxycinnamiques (4,24 mg EAC/g ms). L’étude de la cytotoxicité a montré que cet extrait possède une activité antiproliférative sur les cellules cancéreuses C6, SNB 75, GLI7 et GLI4F11 (CI50 < 0,01 mg/ml).

Two strains of enteropathogenic Gram-positive bacteria (Staphylococcus auricularis, NIAH 11484 and Staphylococcus aureus, IFO 12732) were tested in vitro for their resistance to extracts from tropical chewing stick species, namely, Garcinia mannii Heck, Masularia accuminata (G. Don) Benth, Zanthoxylum gilletii (DeWild) Waterman, Terminalia glaucescens Plauch ex Benth, Azadiracta indica A. Juss, Anogeissus leiocarpus Guill & Perr and Pseudocedrela kotschyi (Schweinf.). The chewing sticks are normally used for oral hygiene and this is felt to be related to their ability to attack bioagents that could invade the mouth during normal nutrition. Results from our study showed that the antibiotic properties of test chewing stick species vary and are target-microbe-specific. Of the species examined, only T. glaucescens showed appreciable broad antibiotic effect against S. aureus and S. auricularis. Intense antibiotic activity against S. aureus occurred when using a 2.0 g/l extract concentration and a 30-h incubation. T. glaucescens also showed intense activity against S. auricularis at 2.0 g/l concentration, 30-h incubation when all other extracts had lost their potency. A. indica is, however, most effective against S. aureus, showing appreciable antibiotic activity at 0.4 g/l concentration, 30-h incubation. Z. gilletii has no antibiotic activity against any of the test bacteria. The antistaphylococcus compounds in T. glaucescens and A. indica are worthy of isolation and further analyses.

Zanthoxylum gilletii is an indigenous tropical tree species that is valued for its structural timber, agroforestry and medicinal properties. Seed of many Zanthoxylum species have been reported to have poor germination. The study investigated the germination of fresh Z. gilletii seed harvested at two maturity stages, green and red (ripe) follicles, and harvested from two provenances: Kakamega and Koiwa in November and December 2006, respectively. Follicles were dried at controlled temperature of 20°C and relative humidity of 20%. During harvesting, Satinwood seed had high MC of 26%, which decreased to 12% after processing and drying. Seed dried to 12.5% MC were divided into two: one seed lot remained unwashed while the other was washed with sodium hydroxide (NaOH) solution. Unwashed seed from Kakamega and Koiwa provenances sown on sand in the glass house gave a germination of 3 and 8%, compared to seed washed with NAOH solution which germinated up to 10 and 23%, respectively, by the 17th week. Washed seed sown on 1% agar in incubators at various constant temperatures (20, 25, 30, and 35°C±1) and alternating temperatures (20/30°C and 15/35°C±1) recorded poor germination of less than 3%, probably due to the presence of chemicals which inhibited germination. These findings suggest that the hard seed coat and oil on the testa influence seed germination and possibly contribute to dormancy exhibited by Z. gilletii seed. Germination of seed from mature green and ripe fruits was similar and therefore Z. gilletii fruits should be harvested when they start to ripen. African Satinwood seed should be washed with soap solution to remove the oil film and fruit appendages on the testa before incubation. These results are still low and there is need for further investigation to improve germination of Z. gilletii seed.

Objectif: Connaitre les plantes medicinales utilisees comme remede dans le traitement des maladies de la peau dans le departement d’Agboville, en Cote d’Ivoire. Methode et resultats: Une etude ethnobotanique realisee dans le departement d’Agboville a permis de recenser 32 especes utilisees dans le traitement des infections cutanees. La methode de la double dilution sur milieu PDA a ete utilisee pour tester in vitro la sensibilite de deux souches fongiques de Sclerotium rolfsii aux extraits de Zanthoxylum gilletii (olon). L’extrait ethanolique a ameliore 8 fois l’activite inhibitrice de l’extrait aqueux. Les CMI et CMF de Sv et St sont de 100 mg/ml et 200 mg/ml pour l’Eaq et 12,5 mg/ml et 25 mg/ml pour l’Eeth, Au niveau des sclerotes La CMI a ete de 6,25 mg/ml pour les deux souches et la CMF, de 12,5 mg/ml et 25 mg/ml pour les souches Sv et St respectivement. Conclusion et application: Les populations rurales du departement d’Agboville detiennent une bonne connaissance des plantes utilisees dans la lutte contre les dermatoses. Zanthoxylum gilletii ., l’une des plantes les plus citees, possede une activite antifongique contre Sclerotium rolfsii , Elle constitue un fongicides pouvant etre utilise dans la lutte biologique contre les champignons telluriques. Mots cles: Zanthoxylum gilletii , extrait aqueux, extrait ethanolique, antifongique, Sclerotium rolfsii English Title: Ethnobotany study and in vitro evaluation of antifungal activity of bark extracts of Zanthoxylum gilletii (De Wild Waterman) on two phytopathogenic strain of Sclerotium rolfsii English Abstract Objective: Learn about medicinal plants used as medicine in the treatment of skin diseases in the department of Agboville, in Cote d’Ivoire. Methods and Results: An ethnobotanical study carried out in the department of Agboville allowed to identified 32 species used in the treatment of skin infections. The method of double dilution on PDA medium was used to test the in vitro sensitivity of two fungal strains of Sclerotium rolfsii to extracts of Zanthoxylum gilletii . Ethanolic extract improved 8 times the inhibitory activity of the aqueous extract. The MIC and MFC of St and Sv were 100 mg / ml and 200 mg / ml for the QAR and 12.5 mg / ml and 25 mg / ml for EETH. Concerning sclerotia, the MIC was 6,25 mg / ml for both strains. The MFC was 12.5 mg / ml and 25 mg / ml for St and Sv strains respectively Conclusion and Application: Rural people of Agboville department hold a good knowledge of plants used in the fight against skin diseases. Zanthoxylum gilletii , one of the most cited plant has antifungal activity against Sclerotium rolfsii . It is a fungicide which can be used in biological control against soil fungi. Keywords: Zanthoxylum gilletii , water extract, ethanol extract, antifungal, Sclerotium rolfsii

Poor regeneration of valuable timber species under closed forest canopy is a major problem affecting regeneration of tree species in Kenyan moist and Afromontane natural forests. This study was conducted in 1998 – 1999 to investigate the influence of shade tolerance, seed sources and insect herbivory on the regeneration of selected heavily exploited timber species (Maesopsis eminii, Zanthoxylum gilletii, Polyscias fulva, and Prunus africana) in Kakamega forest. 58 woody species were recorded in the sample area, most of which occurred at low densities. Twenty species contributed 81.5% of the total stocking. Shade tolerance, seed source, and insect herbivory had influence on the regeneration of the species in varying degrees. Regeneration of Maesopsis eminii and Polyscias fulva appeared to be more influenced by shading (light regime) than insect herbivory. The latter species also seemed to regenerate from seeds stored in soil seed bank. Phytophagous insects seemed to play more significant role in the regeneration of Zanthoxylum gilletii and Prunus africana than that of Maesopsis eminii and Polyscias fulva. As a recommendation, natural forest management should involve creation of “regeneration gaps” to enhance the regeneration of shade intolerant species like Prunus africana and Zanthoxylum gilletii. Sustainable selective logging of valuable timber species is suggested as a way of creating the gaps. Key Words: Natural forest, regeneration, Insect herbivory, Maesopsis eminii, Zanthoxylum gilletii, Polyscias fulva, and Prunus africana Résumé La régénération pauvre des espèces à bois de valeur sous une canopie forestière fermée constitue un problème majeur pour la régénération des espèces d\' arbres dans les forêts humides montagneuses au Kenya. Cette étude, conduite en 1998-1999, a examiné l\'influence de l\'ombrage, de l\'origine des graines et des insectes herbivores sur la régénération des espèces d\'arbres les plus exploitées (Maesopsis eminii, Zanthoxylum giletii, Polyscias fulva et Prunus africana) dans la forêts de Kakamega. Cinquante huit (58) espèces de plantes ligneuses ont été enregistrées, la plupart à faible densité dans les endroits échantillons; 20 espèces constituaient 81.5% du stockage total. Les trois facteurs éxaminés influencent la régénération des espèces étudieés mais á des degrés variés. La régénération de Maesopsis eminii et Polyscias fulva est plus sensible á l\'ombre qu‘à l\'attaque par des insectes. Polyscias fulva se développe aussi à partir des graines enfuies dans le sous sol. Des insectes phytophages influencent plus significativement la régénération de Zanthoxylum giletii et Prunus africana que celle de Maesopsis eminii et Polyscias fulva. Ainsi, l\'aménagement des forêts naturelles doit considérer la création des \"trous de régénération\" pour favoriser des espèces d\'arbres hostiles à l\'ombrage comme Prunus africana et Zanthoxylum giletii. L\'exploitation séléctive soutenue des arbres de valeur est proposée comme moyen de création des ouvertures dans la canopie forestière. Mots clés: Forêt naturelle, régénération, insectes herbivores, Maesopsis eminii, Zanthoxylum giletii, Polyscias fulva, Prunus africanaDiscovery and Innovation Vol 16 (3&4) 2004: 117-125

Poor regeneration of valuable timber species under closed forest canopy is a major problem affecting regeneration of tree species in Kenyan moist and Afromontane natural forests. This study was conducted in 1998 – 1999 to investigate the influence of shade tolerance, seed sources and insect herbivory on the regeneration of selected heavily exploited timber species ( Maesopsis eminii, Zanthoxylum gilletii, Polyscias fulva , and Prunus africana ) in Kakamega forest. 58 woody species were recorded in the sample area, most of which occurred at low densities. Twenty species contributed 81.5% of the total stocking. Shade tolerance, seed source, and insect herbivory had influence on the regeneration of the species in varying degrees. Regeneration of Maesopsis eminii and Polyscias fulva appeared to be more influenced by shading (light regime) than insect herbivory. The latter species also seemed to regenerate from seeds stored in soil seed bank. Phytophagous insects seemed to play more significant role in the regeneration of Zanthoxylum gilletii and Prunus africana than that of Maesopsis eminii and Polyscias fulva . As a recommendation, natural forest management should involve creation of “regeneration gaps” to enhance the regeneration of shade intolerant species like Prunus africana and Zanthoxylum gilletii . Sustainable selective logging of valuable timber species is suggested as a way of creating the gaps. Key Words: Natural forest, regeneration, Insect herbivory, Maesopsis eminii , Zanthoxylum gilletii , Polyscias fulva , and Prunus africana Resume La regeneration pauvre des especes a bois de valeur sous une canopie forestiere fermee constitue un probleme majeur pour la regeneration des especes d\' arbres dans les forets humides montagneuses au Kenya. Cette etude, conduite en 1998-1999, a examine l\'influence de l\'ombrage, de l\'origine des graines et des insectes herbivores sur la regeneration des especes d\'arbres les plus exploitees ( Maesopsis eminii, Zanthoxylum giletii, Polyscias fulva et Prunus africana ) dans la forets de Kakamega. Cinquante huit (58) especes de plantes ligneuses ont ete enregistrees, la plupart a faible densite dans les endroits echantillons; 20 especes constituaient 81.5% du stockage total. Les trois facteurs examines influencent la regeneration des especes etudiees mais a des degres varies. La regeneration de Maesopsis eminii et Polyscias fulva est plus sensible a l\'ombre qu‘a l\'attaque par des insectes. Polyscias fulva se developpe aussi a partir des graines enfuies dans le sous sol. Des insectes phytophages influencent plus significativement la regeneration de Zanthoxylum giletii et Prunus africana que celle de Maesopsis eminii et Polyscias fulva. Ainsi, l\'amenagement des forets naturelles doit considerer la creation des \"trous de regeneration\" pour favoriser des especes d\'arbres hostiles a l\'ombrage comme Prunus africana et Zanthoxylum giletii . L\'exploitation selective soutenue des arbres de valeur est proposee comme moyen de creation des ouvertures dans la canopie forestiere. Mots cles: Foret naturelle, regeneration, insectes herbivores, Maesopsis eminii, Zanthoxylum giletii, Polyscias fulva, Prunus africana Discovery and Innovation Vol 16 (3&4) 2004: 117-125

Pure compounds were isolated from plant extracts with antimalarial activity. The extracts were obtained from the tubers of Cyperus rotundus L. (Cyperaceae), the rootbark of Zanthoxylum gilletii (De Wild) Waterm. (Rutaceae), and the rootbark of Margaritaria discoidea (Baill.) Webster (Euphorbiaceae). The most active compounds included (IC50 within brackets): alpha-cyperone (1) (5.5 micrograms/ml), N-isobutyldeca-2,4-dienamide (2) (5.4 micrograms/ml), and securinine (3) (5.4 micrograms/ml). A mixture of autoxidation products of beta-selinene was found to be the most active antimalarial substances obtained from C. rotundus (5.6 micrograms/ml.