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Phytochemical composition and subacute toxicity of ethanolic extract of Eucheuma denticulatum on male Wistar albino rats
(Elsevier B.V., 2026-05-07) Muze, Mary; Mpolya, Emmanuel; Mollay, Clara
Eucheuma denticulatum is a rich source of secondary metabolites with established medicinal importance, including its potential use in diabetes management. The current study was conducted to determine the subacute toxicity and the FTIR and LC-MS analysis of the ethanolic extract of E. denticulatum following repeated exposure, which is of greater therapeutic value. The crude extract of E. denticulatum was prepared using ethanol and administered orally to 4 groups, with each group containing 6 male rats at doses of 300, 600, and 1000 mg/kg, in accordance with the guidelines of the Organization for Economic Cooperation and Development (OECD) (407) over 28 days. Following this, hematological, biochemical, histopathological, and organ and animal weight parameters were examined to assess the toxicological effects of the macroalgae extract. The macroalgae extract did not induce any significant differences in biochemical parameters or hematological results (P > 0.05). However, basophils, hematocrit, and mean corpuscular hemoglobin concentration showed only slight statistical differences in a dose-dependent manner, and all values remained within normal acceptable ranges. The maximum administered dosage showed slight morphological alterations in the kidneys and liver. Body weights in the treatment groups showed time-dependent increases comparable to those of the control group; however, there were no significant variations in organ weights. The FTIR analysis revealed the presence of polyphenols, flavonoids, amides, carboxylic acids, and esters, and LC-MS identified potential biological antidiabetic compounds such as phytol, hexadecenoic acid, tetradecanoic acid, and Eicosapentaenoic acid (EPA). Therefore, preventive steps must be considered when using the E. denticulatum extract as a long-term therapeutic application, especially at large doses of 1000 mg/kg b.w.
Perceptions and behavioral intentions of smallholder farmerstoward the adoption of solar dryers for postharvest management ofperishable horticultural products in Tanzania
(Taylor & Fransic Online, 2026-05-12) Kimaro, Dismas; Kivevele, Thomas; Sanni, Maruf; Kingiri, Ann; Nyangarika, Anthony
Persistent postharvest losses among smallholder farmers in developing countries, particularly in horticultural value chains, continue to threaten food security and income stability. Although solar dryers offer a cost-effective and environmentally sustainable solution, their adoption remains limited. Existing studies have mainly emphasized technical and economic performance, with limited attention to behavioral factors influencing adoption decisions. This study examined farmers’ perceptions of solar dryers and the influence of sociodemographic, cognitive, and behavioral traits on adoption intention. Data from 291 horticultural smallholder farmers in northern Tanzania were analyzed using descriptive statistics and Partial Least Squares Structural Equation Modeling. Results revealed moderate perceived usefulness (PU) (mean = 3.08) and low perceived ease of use (PEOU) (mean = 2.55). Optimism (β = 0.517; 0.554; and 1.107) and innovativeness (β = 0.444; -0.158; and 0.255) significantly influence PEOU, PU, and BI directly, respectively. Also, discomfort (β = -0.134) significantly influences PEOU of solar dryers. Likewise, PEOU (β = 0.501 and 0.231) significantly influences both PU and BI, respectively, while PU (β = 0.449) significantly influences BI. These findings highlight the importance of strengthening positive technology readiness traits through financial and non-financial incentives to accelerate the adoption of solar drying technologies among smallholder farmers.
One health analysis of antimicrobial resistance in Escherichia coli from humans, animals, and the environment
(Oxford University Press, 2026-04-03) Beatus, Lyimo
Antimicrobial resistance (AMR) poses a critical public health threat, with evidence suggesting the transfer of resistance genes between humans, animals, and the environment. This study investigates the distribution of AMR genes, plasmid types, and the population structure of Escherichia coli isolates from humans, livestock, fish, and the environment in Tanzania, with a subset of data from Kenya, using a One Health approach. A total of 174 Whole-genome sequencing (WGS) data were analyzed to identify AMR genes and evaluate their population structure. The findings reveal widespread dissemination of AMR genes across all sources. Aminoglycoside resistance genes and β-lactam resistance genes were prevalent across all environments. Quinolone resistance mutations were detected in isolates from humans, livestock, fish, and the environment. Tetracycline resistance genes were found in humans, livestock, and fish. Plasmid types IncFIA, IncI1, and IncFII exhibited extensive cross-source sharing, with strong connectivity between human and livestock. Principal Component Analysis (PCA) revealed that E. coli isolates from Kenya formed a tight, distinct cluster, while other isolates were more dispersed. These findings emphasize the interconnected nature of AMR across human, animal, and environmental sectors and underscore the need for integrated surveillance under a One Health framework to monitor and control the spread of clinically significant AMR genes.
Availability and Implementation
The genomic datasets analyzed in this study are available from public repositories. Bioinformatics analyses were conducted using established pipelines and standard tools for AMR gene detection, plasmid typing, and population structure analysis.
Macroeconomic transmission effects on stock market performance in Tanzania: evidence from a structural VAR analysis
(Frontiers, 2026-05-20) Peter, Michael; Mirau, Silas; Sinkwembe, Emmanuel; Kasumo, Christian; Guambe, Calisto
This study examines the dynamic interactions between key macroeconomic indicators and stock market performance in Tanzania, a frontier market in sub-Saharan Africa. Using a Structural Vector Autoregression (SVAR) framework, we analyze monthly data for the Tanzania Share Index (TSI), gold returns, inflation rate, and electricity consumption employed as a high-frequency proxy for real economic activity to address the temporal limitations of quarterly GDP data common in developing economies. Johansen co-integration analysis identifies four stable long-run relationships, while a one-lag VAR specification suggests rapid adjustment dynamics. Impulse response functions reveal that shocks dissipate within three to five months. Notably, the TSI responds negatively to economic activity shocks, indicating a structural mismatch between stock market valuations and real-sector growth. Forecast error variance decomposition further underscores this decoupling: own shocks explain approximately 75%–80% of TSI fluctuations, suggesting that within this four-variable system, macroeconomic factors account for a modest share of equity variation. Gold returns, however, exhibit persistent positive responses to inflation shocks, confirming their role as an inflation hedge. Overall, the findings suggest Tanzania's financial market remains relatively disconnected from real-sector fundamentals, reflecting its early stage of financial deepening. Policy recommendations emphasize strengthening financial infrastructure, enhancing macro-financial linkages, and developing robust commodity-price monitoring systems to improve signal transmission to capital markets.
Invasive Plant Impacts on Soil Macrofauna through Allelopathy and Environmental Modification
(CABI Digital Library, 2026-05-11) Ojija, Fredrick; Bacaro, Giovanni; Ogwu, Matthew; Akomolafe, Gbenga; Laizer, Hudson; Shayo, Philipina; Malunguja, Gisandu
Soil macrofauna taxonomic groups such as annelids (earthworms), arthropods (insects and crustaceans) and molluscs (gastropods/snails) play an essential role in soil ecosystems (van Hengstum et al., 2014; Zulu et al., 2022; Mamabolo et al., 2024). These organisms help convert organic matter into forms that can be utilized by plants, ultimately supporting soil fertility (Sofo et al., 2020; Mamabolo et al., 2024). They influence soil structure, organic matter decomposition, nutrient cycling, soil aeration and ecosystem functioning (van Hengstum et al., 2014; Ibrahima et al., 2017). Thus, their presence and diversity are integral to maintaining soil fertility and productivity, making them important bioindicators for assessing soil health (Rousseau et al., 2013; Sofo et al., 2020). Soil macrofauna physically and biologically alter the soil structure, enhancing the permeability of the soil and improving water infiltration (Zhou et al., 2022). Besides, they contribute to the creation of microhabitats for other organisms, promoting biodiversity conservation (Huerta and van der Wal, 2012). For instance, earthworms, through their burrowing and feeding activities, not only recycle nutrients but also create channels in the soil that facilitate the movement of water and air (Ibrahima et al., 2017; Yang et al., 2024).
Soil macrofauna – ants, termites and beetles – are involved in the breakdown of organic matter, including plant litter and animal remains, thereby playing a role in nutrient cycling (Jouquet et al., 2011; Ibrahima et al., 2017; Mamabolo et al., 2024). The presence and activity of these macrofauna can also influence the abundance and diversity of soil microorganisms, further enhancing nutrient cycling (Zhou et al., 2022). Research conducted by Liu et al. (2020) and Singh et al. (2019) reveals that earthworms are particularly effective at enhancing soil aggregation, which improves the structural stability of the soil. This effect is also seen in termite species, which build intricate tunnel systems that help aerate the soil and facilitate nutrient movement (Black and Okwakol, 1997; Sileshi et al., 2010; Jouquet et al., 2011, 2018; Ali et al., 2013). Table 10.1 provides some common examples of soil macrofauna species.