Lake Victoria (L. Victoria) is the largest African tropical and freshwater lake, with one of the highest pollution levels, globally. It is shared among Uganda, Kenya and Tanzania, but it is drained only by the river Nile, the longest river in Africa. Though environmental studies have been conducted in the lake, investigations of the heavy metals (HMs) contamination of sediments from fish landing sites and ports on the Ugandan portion of L. Victoria are limited. In this study, sediments of an urban, industrial and fish landing site (Port Bell) on L. Victoria, Uganda was investigated to establish its HMs pollution levels and potential health risks to humans and ecosystems. Sediment samples were collected in triplicate (n = 9) from three different points of Port Bell, digested and analyzed using atomic absorption spectrometry for the presence of these HMs: copper (Cu), lead (Pb), cadmium (Cd) and chromium (Cr). The average daily dose through dermal contact and hazard quotient (HQ) were calculated to assess the health risk that is associated with dredging works (lake sand mining). Four geochemical enrichment indices: contamination factor (CF), geo-accumulation index (I_geo), pollution load index (PLI) and potential ecological risk (PERI) were used to quantify the contamination of the HMs in the sediments. The results showed that the mean HM content of the samples ranged from: 6.111 ± 0.01 to 7.111 ± 0.002 mg/kg for Cu; from 40.222 ± 0.003 to 44.212 ± 0.002 mg/kg for Pb; from 0.352 ± 0.007 to 0.522 ± 0.010 mg/kg for Cr; from 3.002 ± 0.002 to 3.453 ± 0.003 mg/kg for Cd. Health risk assessments indicated that there are no discernible non-carcinogenic health risks that could arise from the dredging works that are conducted in the study area as the indices were all below one. The contamination factors that were obtained suggest that Cd has reached a state of severe enrichment in the sediments (CF > 6). An assessment using I_geo established that the sediments were not contaminated with regards to Cu and Cr, but they exhibited low-to-median and median contamination with respect to Pb and Cd, respectively. Though the pollution load indices show that the contamination levels raise no serious concerns, the potential ecological risk indices show that there is considerable pollution of the Port Bell sediments, particularly with regard to Cd. Upon examination using multivariate statistical analyses, Cd and Cr showed a strong correlation which alluded to their introduction from anthropogenic sources. Based on the sedimentary HMs concentrations and the environmental indices that are employed in this study, it is recommended that the spatial variations in the concentrations of the HMs in water, sediments and biota should be monitored.

Aim: To perform phytochemical screening of Plumbago zeylanica L. root extracts and assess the claim of its use in traditional management of erectile dysfunction in Uganda through evaluation of the aphrodisiac effect of its aqueous extracts in male Wistar rats. Study Design: This study employed both qualitative and quantitative research designs. Place and Duration of Study: All research work were performed at the Department of Biological Sciences, Gulu University, Gulu, Uganda between August 2019 and December 2019. Methodology: Classical phytochemical screening of aqueous and methanolic extracts of Plumbago zeylanica roots were performed following standard methods. Aqueous extracts were administered to Male Wistar rats and the effect of the extracts on the mounting and intromission frequencies were determined. Results: Glycosides, phenols, saponins, quinones, terpenoids and steroids were present in both methanolic and aqueous extracts. Alkaloids were present in methanolic extracts only while tannins and phlobatannins were only present in aqueous extracts. Flavonoids, coumarins and anthraquinones were not detected in both extracts. Aqueous root extracts of Plumbago zeylanica produced pro-sexual stimulatory effects in male rats when administered at 150, 300 and 450 mg/kg body weight. Conclusion: The results support the use of Plumbago zeylanicaroots by indigenous people in Uganda to increase libido, treat premature ejaculation and erectile dysfunction. The extracts had low sexual enhancement in sexually inexperienced male rats and therefore, further studies using experienced animal models are needed to better apprehend the prosexual effects of P. zeylanica roots. The toxicity of the extracts as well as structural elucidation and pharmacological evaluation of the responsible bioactive compounds merit further studies.

Euclea divinorum Hiern (Ebenaceae) is a medicinal plant widely used in Yemen, Eastern and Southern Africa in traditional phytotherapy. This review was an attempt to compile a comprehensive report on its ethnomedicinal uses, phytochemicals, pharmacological activities, and toxicity, lending credence to the use of its various parts in herbal medicine. The literature encountered indicated that herbal formularies from different parts of Euclea divinorum (E. divinorum) are majorly used for traditional treatment of odontological, dermatological, respiratory, reproductive, and gastrointestinal ailments. At least 18 compounds have been isolated and characterized in extracts of E. divinorum, while 31 others have been identified in the crude extracts analyzed by GC-MS. Extracts, as well as isolated compounds from E. divinorum stem, stem barks, leaves, and roots, showed renoprotective, antiproliferative, antinociceptive, contractile, proteolytic, diuretic, antiprotozoal, anti-giardial, antioxidant, anti-inflammatory, antimicrobial, molluscicidal, and insecticidal activities. Further research is warranted to explore other pharmacological properties such as antisnake venom, aphrodisiac, antidiabetic, analgesic, and antimycobacterial activities and the responsible bioactive compounds in the different parts of E. divinorum claimed in herbal medicine. The composition and bioactivities of essential oils from this species also warrant further studies.