School of Biological Sciences
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Item Additions and corrections to the bryophyte flora of Ghana, including a new species of Cololejeunea (Spruce) Schiffn. (Lejeuneaceae, Marchantiophyta)(Taylor & Francis Group, 2021) Hodgetts, N.G.; Ameka, G.; Agyei, R.; Dankwah, C.Introduction. The bryophytes of Ghana are under-recorded, but the country has several important and relatively extensive examples of West African forest likely to support an interesting flora. Of these, Atewa Forest was targeted for survey in 2014, resulting in many records, including 58 taxa new to Ghana. This paper reports the results of further fieldwork, both in Atewa and elsewhere, in 2017, and makes some necessary additions and amendments to previously published data. Methods. Bryophyte fieldwork was carried out in key forest sites in southern Ghana during November 2017, and was followed by targeted herbarium studies. Key results. A new species, Cololejeunea ankasica, is described, and a new site for the rare Ghanaian endemic C. calcarata reported; a further 27 taxa new to Ghana are recorded, and amendments made to previously published information. Conclusions. This study shows that even lowland areas of remaining forest in Ghana are bryologically interesting and that bryophytes are an important but still under-recorded part of Ghana’s biodiversity. It also strengthens the case for National Park status for Atewa Forest, which remains the only known site in Ghana for many species characteristic of higher altitude forest.Item Microbial Diversity and Metabolite Profile of Fermenting Millet in the Production of Hausa koko, a Ghanaian Fermented Cereal Porridge(Frontiers in Microbilogy, 2021) Atter, A.; Diaz, M.; Tano-Debrah, K.; Kunadu, A.P.; Mayer, M.J.; Colquhoun, I.J.; Nielsen, D.S.; Baker, D.; Narbad, A.; Amoa-Awua, W.Hausa koko is an indigenous porridge processed from millet in Ghana. The process involves fermentation stages, giving the characteristic organoleptic properties of the product that is produced largely at a small-scale household level and sold as a street food. Like many other indigenous foods, quality control is problematic and depends on the skills of the processor. In order to improve the quality of the product and standardize the process for large-scale production, we need a deeper understanding of the microbial processes. The aim of this study is to investigate the microbial community involved in the production of this traditional millet porridge and the metabolites produced during processing. High-throughput amplicon sequencing was used to identify the bacterial (16S rRNA V4 hypervariable region) and fungal [Intergenic Transcribed Spacer (ITS)] communities associated with the fermentation, while nuclear magnetic resonance (NMR) was used for metabolite profiling. The bacterial community diversity was reduced during the fermentation processes with an increase and predominance of lactobacilli. Other dominant bacteria in the fermentation included Pediococcus, Weissella, Lactococcus, Streptococcus, Leuconostoc, and Acetobacter. The species Limosilactobacillus fermentum and Ligilactobacillus salivarius accounted for some of the diversities within and between fermentation time points and processors. The fungal community was dominated by the genus Saccharomyces. Other genera such as Pichia, Candida, Kluyveromyces, Nakaseomyces, Torulaspora, and Cyberlindnera were also classified. The species Saccharomyces cerevisiae, Stachybotrys sansevieriae, Malassezia restricta, Cyberlindnera fabianii, and Kluyveromyces marxianus accounted for some of the diversities within some fermentation time points. The species S. sansevieria and M. restricta may have been reported for the first time in cereal fermentation. This is the most diverse microbial community reported in Hausa koko. In this study, we could identify and quantify 33 key different metabolites produced by the interactions of the microbial communities with the millet, composed of organic compounds, sugars, amino acids and intermediary compounds, and other key fermentation compounds. An increase in the concentration of organic acids in parallel with the reduction of sugars occurred during the fermentation process while an initial increase of amino acids followed by a decrease in later fermentation steps was observed.Item GJB2 and GJB6 Mutations in Hereditary Recessive Non-Syndromic Hearing Impairment in Cameroon(Genes, 2019-10-25) Adadey, S.M.; Wonkam, E.T.; Chimusa, E.; Noubiap, J.J.; Fokouo, J.V.F.; Wonkam, A.This study aimed to investigate GJB2 (connexin 26) and GJB6 (connexin 30) mutations associated with familial non-syndromic childhood hearing impairment (HI) in Cameroon. We selected only families segregating HI, with at least two a ected individuals and with strong evidence of non-environmental causes. DNA was extracted from peripheral blood, and the entire coding region of GJB2 was interrogated using Sanger sequencing. Multiplex PCR and Sanger sequencing were used to analyze the prevalence of the GJB6-D3S1830 deletion. A total of 93 patients, belonging to 41 families, were included in the analysis. Hearing impairment was sensorineural in 51 out of 54 (94.4%) patients. Pedigree analysis suggested autosomal recessive inheritance in 85.4% (35/41) of families. Hearing impairment was inherited in an autosomal dominant and mitochondrial mode in 12.2% (5/41) and 2.4% (1/41) of families, respectively. Most HI participants were non-syndromic (92.5%; 86/93). Four patients from two families presented with type 2 Waardenburg syndrome, and three cases of type 2 Usher syndrome were identified in one family. No GJB2 mutations were found in any of the 29 families with non-syndromic HI. Additionally, the GJB6-D3S1830 deletion was not identified in any of the HI patients. This study confirms that mutations in the GJB2 gene and the del(GJB6-D13S1830) mutation do not contribute to familial HI in Cameroon.Item DNA barcoding of african podostemaceae (river-weeds): A test of proposed barcode regions(Taxon, 2010-02) Kelly, L.J.; Ameka, G.K.; Chase, M.W.DNA barcoding has the possibility for application in many fields, ranging from biological inventory and species discovery to forensics and quality control. Barcoding could have great utility within the aquatic angiosperm family Podostemaceae, as these plants can be extremely difficult to identify on the basis of morphological characters alone, but are important components of tropical rivers and face threats from increased water pollution. Several potential barcodes for land plants have been suggested, including two 3-locus combinations proposed by the Plant Working Group of the Consortium for the Barcode of Life. These loci, matK, rpoB, rpoC1, and trnH -psbA, were tested for their potential utility in African members of the Podostemaceae. Our results show that although the rpoC1 region performs best in terms of universality of amplification and sequencing, the superior resolving power of matK makes it the most promising of the regions for use in barcoding. In the light of these results, we discuss the potential to apply barcoding to Podostemaceae of Africa and make suggestions for the directions of future work to exploit the full potential of this new technology in this group of plants.Item Enigmatic morphology of Djinga felicis (Podostemaceae - Podostemoideae), a badly known endemic from northwestern Cameroon(Botanical Journal of the Linnean Society, 2009-05) Ghogue, J.P.; Ameka, G.K.; Grob, V.; Huber, K.A.; Pfeifer, E.; Rutishauser, R.Djinga is a monotypic genus restricted to the Cameroon Ridge ('Dorsale Camerounaise') of NW Cameroon. Besides the type locality Mount Djinga (Adamawa Province, near Tignère), it also grows in waterfalls near Mount Oku (NW Province). This paper describes the structure and development of Djinga felicis using scanning electron microscopy and microtome sections. Cusset's protologue is enriched considerably. Roots are green, dorsiventrally flattened and adherent to submerged rocks. They are broad ribbons or crusts (up to 1 cm broad) which branch exogenously. Root-borne shoots (up to 17 cm) have filamentous leaves with sheaths and (occasionally) attached stipules. Flowers are borne as part of reproductive short shoots which arise exogenously along the stems and endogenously along the roots. Djinga shows non-axillary stem branching. Reproductive shoots along the main stem usually stay short. They arise from the abaxial side of double-sheathed leaves, a key innovation of Podostemoideae. These short shoots shift into pocket-like stem positions clearly below their associated leaves. Each flower bud inside a spathella is erect, but with an inclined ovary. The flowers are unistaminate with a broad connective. Unlike many other Podostemoideae, the tricolpate pollen grains are arranged in both dyads and monads. The ovary is globular and unilocular. The mature 8-ribbed capsule dehisces by two slightly unequal valves, releasing 40-50 seeds. © 2009 The Linnean Society of London.Item Perceived incentives and barriers to exclusive breastfeeding among periurban ghanaian women(Journal of Human Lactation, 2009-02) Otoo, G.E.; Lartey, A.A.; Pérez-Escamilla, R.Focus group discussions were conducted to elicit the perceived incentives and barriers to exclusive breastfeeding in Ghana. Thirty-five breastfeeding women were recruited from the Manya and Yilo Krobo districts of the eastern region. Participants had a mean age of 27.5 years and had at least one child < 4 months old. Almost all of the participants believed that exclusive breastfeeding is the superior infant feeding method and should be practiced for the first 6 months postpartum. However, there was widespread belief that infants can be given water if it is clean. Mothers reported that exclusive breastfeeding was easier when breast milk began to flow soon after delivery. The main obstacles to exclusive breastfeeding identified were maternal employment, breast and nipple problems, perceived milk insufficiency, and pressure from family. Addressing the concerns put forward by these participants can be used to enhance exclusive breastfeeding promotion in this region. © Copyright 2009 International Lactation Consultant Association.Item Deconstructing "malaria": West Africa as the next front for dengue fever surveillance and control(Acta Tropica, 2014-06) Stoler, J.; al Dashti, R.; Anto, F.; Fobil, J.N.; Awandare, G.A.Presumptive treatment of febrile illness patients for malaria remains the norm in endemic areas of West Africa, and "malaria" remains the top source of health facility outpatient visits in many West African nations. Many other febrile illnesses, including bacterial, viral, and fungal infections, share a similar symptomatology as malaria and are routinely misdiagnosed as such; yet growing evidence suggests that much of the burden of febrile illness is often not attributable to malaria. Dengue fever is one of several viral diseases with symptoms similar to malaria, and the combination of rapid globalization, the long-standing presence of Aedes mosquitoes, case reports from travelers, and recent seroprevalence surveys all implicate West Africa as an emerging front for dengue surveillance and control. This paper integrates recent vector ecology, public health, and clinical medicine literature about dengue in West Africa across community, regional, and global geographic scales. We present a holistic argument for greater attention to dengue fever surveillance in West Africa and renew the call for improving differential diagnosis of febrile illness patients in the region. © 2014 The Authors.Item Impact of small quantity lipid-based nutrient supplements on infant and young child feeding practices at 18 months of age: results from four randomized controlled trials in Africa(Maternal and Child Nutrition, 2017-07) Arimond, M.; Abbeddou, S.; Kumwenda, C.; Okronipa, H.; Hemsworth, J.; Jimenez, E.Y.; Ocansey, E.; Lartey, A.; Ashorn, U.; Adu-Afarwuah, S.; Vosti, S.A.; Hess, S.Y.; Dewey, K.G.Optimal infant and young child feeding (IYCF) practices can help ensure nutrient adequacy and support healthy growth and development. Small-quantity lipid-based nutrient supplements (SQ-LNS) have been proposed to help fill nutrient gaps, but little is known about the impact of provision of SQ-LNS on breastfeeding or complementary feeding practices. In the context of four coordinated randomized controlled nutrient supplementation trials in diverse sites in Africa, we compared IYCF practices at infant age 18 months (after 9–12 months of supplementation) between those receiving and not receiving SQ-LNS. Practices were assessed by caregiver recall. Continued breastfeeding ranged from 74% (Ghana site) to 97% (Burkina Faso site) and did not differ between groups in any site; prevalence of frequent breastfeeding also did not differ. In two sites (Burkina Faso and Malawi), infants receiving SQ-LNS were more likely to meet the World Health Organization recommendations for frequency of feeding (percentage point differences of 12–14%, P < 0.0001 and P = 0.005, respectively; the remaining two sites did not have data for this indicator). Most indicators of infant dietary diversity did not differ between groups in any site, but in the same two sites where frequency of feeding differed, infants receiving SQ-LNS were less likely to have low frequency of consumption of animal-source foods in the previous week (percentage point differences of 9–19% for lowest tertile, P =.02 and P = 0.04, respectively). We conclude that provision of SQ-LNS did not negatively impact self-reported IYCF practices and may have positively impacted frequency of feeding. © 2016 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.Item People and wildlife: Conflicts arising around the Bia Conservation Area in Ghana(Journal for Nature Conservation, 2013-10) Harich, F.K.; Treydte, A.C.; Sauerborn, J.; Owusu, E.H.Human-wildlife conflicts have drastically increased around conservation areas in Africa over the last decades. Underlying causes are similar across regions and can most often be attributed to land-use changes and increasing human populations. However, wildlife species composition involved in conflicts can vary tremendously across sites. Conflict assessment often focuses on prominent species such as elephants or other large mammals, and information on smaller wildlife species involved in conflicts is often lacking. We conducted 100 interviews in 10 communities around the Bia Conservation Area (BCA), Ghana, to address the type and extent of damage as well as possible factors influencing the risk of crop-raids. We assessed wildlife presence and relative densities through indirect observations on transects and spoor-plots in the transition zone between BCA and agricultural land. Crop-raiding was present across all communities interviewed but was more than twice as high in the north compared to the south. Squirrels (Sciuridae spp.) were the most frequent crop-raiding species (92% of farmers experienced damage), but elephants (Loxodonta africana cyclotis [Matschie, 1900]) were nevertheless the major conflict generating species (84% of farmers experienced damage). Squirrel signs were 75 times as frequent as any other species recorded in the farmland. Cocoa (Theobroma cacao) was most frequently raided (99%), followed by cassava (Manihot esculenta) and yam (Dioscorea spp.). Raiding might have been promoted through inappropriate agricultural practices while only few current mitigation strategies have been successful so far. Promising strategies include chili fences and buffer zones, in which less susceptible crops such as chili pepper are planted. Further education of farmers on mitigation measures is needed, including training on improved farming practices. © 2013 Elsevier GmbH.Item Continent-wide panmixia of an African fruit bat facilitates transmission of potentially zoonotic viruses(Nature Communications, 2013-11) Peel, A.J.; Sargan, D.R.; Baker, K.S.; Hayman, D.T.S.; Barr, J.A.; Crameri, G.; Suu-Ire, R.; Broder, C.C.; Lembo, T.; Wang, L.-F.; Fooks, A.R.; Rossiter, S.J.; Wood, J.L.N.; Cunningham, A.A.The straw-coloured fruit bat, Eidolon helvum, is Africa's most widely distributed and commonly hunted fruit bat, often living in close proximity to human populations. This species has been identified as a reservoir of potentially zoonotic viruses, but uncertainties remain regarding viral transmission dynamics and mechanisms of persistence. Here we combine genetic and serological analyses of populations across Africa, to determine the extent of epidemiological connectivity among E. helvum populations. Multiple markers reveal panmixia across the continental range, at a greater geographical scale than previously recorded for any other mammal, whereas populations on remote islands were genetically distinct. Multiple serological assays reveal antibodies to henipaviruses and Lagos bat virus in all locations, including small isolated island populations, indicating that factors other than population size and connectivity may be responsible for viral persistence. Our findings have potentially important public health implications, and highlight a need to avoid disturbances that may precipitate viral spillover. © 2013 Macmillan Publishers Limited. All rights reserved.