http://hdl.handle.net/123456789/6 2026-08-05T18:44:51Z http://hdl.handle.net/123456789/19834 Sperm-disrupting activity of a root bark fraction of Flueggea virosa (Roxb. ex willd.) royle uncovered using LC-MS/MS profiling and functional evaluation Kehongo M. Nyanguru, Caroline Maina, Mutiat Ibrahim, James Kuria, Ephantus Ndirangu, Sospeter Ngoci Njeru, Abdullahi Abdulraheem, Edwin Murungi, Moses Obimbo, Adeyemi O. Aremu, Aloys Mosima Osano, Samwel Cheruiyot, Margaret O. Ilomuanya, Peter Waweru Mwangi, Elizabeth Kigondu Introduction: While Flueggea virosa (Roxb. Ex Willd.) Royle root bark is traditionally used in several parts of East Africa for fertility regulation, its contraceptive potential has not been systematically investigated. Given the paucity of safe, reversible, non-hormonal contraceptives for women, this study evaluated a root bark fraction for sperm-disrupting, intravaginal contraceptive activity using functional assays and a rabbit proof-of-concept model. Methods: Following extraction and fractionation of authenticated root bark, the resulting extracts were evaluated for cytotoxicity in Vero cells and for disruption of human sperm functions by ascertaining immobilization, revival, viability, cervical mucus penetration and acrosin-related activity. Thereafter, chemical profiling of the most active fraction was performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for descriptive annotation. Moreover, in vivo contraceptive efficacy and short-term local safety (10 days) were determined after intravaginal administration of the fraction in rabbits by histological examination of cervicovaginal tissues. Results: The methanolic fraction (KBLM) demonstrated the strongest activity, completely immobilizing sperm, abolishing sperm revival after washing, markedly reducing sperm viability, strongly inhibiting cervical mucus penetration and suppressing acrosin-related activity at 1.62 mg/mL. In a rabbit proof-ofconcept experiment, a single intravaginal dose prevented pregnancy at all tested concentrations (3.9, 7.8, and 15.6 mg/mL). Besides, repeated OPEN ACCESS EDITED BY Maša Knez Marevci, University of Maribor, Slovenia REVIEWED BY Tushar Dhanani, Florida Agricultural and Mechanical University, United States Parasuraman S, AIMST University, Malaysia *CORRESPONDENCE Kehongo M. Nyanguru, kehongo@mmarau.ac.ke, kehongomoses1995@gmail.com Elizabeth Kigondu, m_kigondu@yahoo.com, ekigondu@kemri.go.ke RECEIVED 20 March 2026 REVISED 11 June 2026 ACCEPTED 15 June 2026 PUBLISHED 01 July 2026 CITATION Nyanguru KM, Maina C, Ibrahim M, Kuria J, Ndirangu E, Njeru SN, Abdulraheem A, Murungi E, Obimbo M, Aremu AO, Osano AM, Cheruiyot S, Ilomuanya MO, Mwangi PW and Kigondu E (2026) Spermdisrupting activity of a root bark fraction of Flueggea virosa (Roxb. ex willd.) royle uncovered using LC-MS/MS profiling and functional evaluation. Front. Pharmacol. 17:1835308. doi: 10.3389/fphar.2026.1835308 COPYRIGHT © 2026 Nyanguru, Maina, Ibrahim, Kuria, Ndirangu, Njeru, Abdulraheem, Murungi, Obimbo, Aremu, Osano, Cheruiyot, Ilomuanya, Mwangi and Kigondu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Frontiers in Pharmacology 01 frontiersin.org intravaginal exposure for 10 days revealed absent-to-mild cervicovaginal changes. Chemical fingerprinting putatively annotated flavonoid-, tannin-, and phenolicrelated features, including catechin, quercetin derivatives, rutin, corilagin, and kaempferol glycosides, as prominent features of KBLM. Conclusion: Our findings have demonstrated the sperm disruption activity of the methanolic fraction of F. virosa root bark. The observed disruption of multiple sperm functions, observed efficacy in a rabbit model and absent-to-mild shortterm local tissue changes support additional preclinical investigations of the extract geared towards further functional characterization, extended safety testing, standardization, and potential formulation of an intravaginal contraceptive. 2026-07-01T00:00:00Z http://hdl.handle.net/123456789/19833 Effects of forest degradation on bats at the South and North Nandi Forests, Western Kenya Sospeter Kibiwot, Millicent J. Bungei, Johnstone Kimanzi, David B. Wechuli, Paul W. Webala Habitat loss and degradation pose significant threats to biodiversity, especially in tropical regions characterized by high biodiversity levels and elevated deforestation rates. However, there is a lack of sufficient information concerning the effects of such disturbances on bats (Mammalia: Chiroptera) in tropical Africa. This research investigated the impact of habitat degradation on bat communities in two forests of varying sizes, South Nandi and North Nandi, located in western Kenya, through bat capture methods. Tree density and forest human use intensity served as predictors for relative bat abundance and species richness. A total of 6,003 bats were recorded, representing 21 species across seven families, during a comprehensive study involving 5,322 hours of mist-netting and 4,224 hours of harp trapping. A progressive decline in species richness (S) was observed from the forest interiors (S = 17) to the edges (S = 16) and the matrices (S = 12) at both forests. Fruit bats (n = 3427; 61.7%) were predominantly detected at the edges and within the matrices, with a limited presence in the forest interior. Conversely, forest-interior insectivorous bats and those foraging in confined spaces (n = 260; 58.6%) were primarily recorded within the forest interiors. Forest specialists exhibited significant correlations with tree density, whereas frugivores and edge- and open-space foraging species showed positive responses to human activity indicators, including cut stumps, charcoal kilns, and footpaths in highly degraded matrices and along forest edges. Consequently, specialized bat species are particularly vulnerable to habitat loss and degradation. 2026-06-01T00:00:00Z http://hdl.handle.net/123456789/19832 The IPBES invasion‑management framework supports informed decision‑making for managing biological invasions Chika Egawa, Sankaran K. V., Andy W. Sheppard, Evangelina Schwindt, Llewellyn C. Foxcroft, Sonia Vanderhoeven, Lora Peacock, Maria L. Castillo, Rafael D. Zenni, Jana Müllerová, Ana Isabel González Martínez, John K. Bukombe, Wyclife Wanzala, Dongang C. Mangwa, Tom August, Helen E. Roy, Aníbal Pauchard, Peter Stoett, Tanara Renard Truong The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) Thematic Assessment Report on Invasive Alien Species and Their Control presents a “conceptual diagram of management-invasion continuum”, introducing a versatile framework to support decision-making on the management of biological invasions. Drawing on an extensive synthesis of current knowledge, this IPBES invasion-management framework has been developed to broaden the scope of existing invasion curves—which primarily overlay generic management objectives onto a sigmoid curve depicting the expansion of the afected area over time—and to illustrate the applicability of the concept of efective management at diferent stages of the biological invasion process. To introduce the IPBES invasion-management framework to a wider audience, this paper explains the features of the framework and defnes the invasion-stage-based management approaches and the potential outcomes envisaged therein. Refecting the currently limited management options for biological invasions in marine and other connected-water systems, unlike in terrestrial and closed-water systems, the IPBES invasion-management framework clearly distinguishes between these two groups of systems. For each, it presents management approaches including three key factors that decision-makers should consider concurrently: management objectives, targets, and actions. This framework supports informed decision-making in the management of biological invasions in all ecosystems. 2026-04-01T00:00:00Z http://hdl.handle.net/123456789/19831 Phytochemical profling, spectroscopic characterization, and acaricidal activity of Tephrosia vogelii leaf extract from Laikipia county, Kenya John Wamumwe Mwangi, James Ndiritu, Bakari Chaka This study aimed to profle the phytochemical profling constituents, characterize the functional groups spectroscopically, and evaluate the acaricidal activity of Tephrosia vogelii leaf extract from Laikipia County, Kenya. Ultrasound assisted sequential extraction using n-hexane, chloroform, and ethanol was employed to obtain crude leaf extracts, followed by qualitative phytochemical screening, FTIR and GC–MS analysis, and AAS based heavy metal quantifcation. The ethanol extract was further tested for acaricidal activity against Rhipicephalus sanguineus using adult and larval immersion tests. Results revealed a rich spectrum of bioactive compounds, including favonoids and rotenoids, saponins, alkaloids, terpenoids, phenols, and glycosides, with deguelin and tephrosin identifed as key acaricidal agents. FTIR and GC–MS showed characteristic peaks at 3446.79 cm⁻ 1 (O–H/N–H), 1743.65 cm⁻ 1 (C=O lactone), and 1535.34 cm⁻ 1 (aromatic C=C), consistent with rotenoid and favonoid structures. AAS detected elevated levels of heavy metals such as Fe, Mn, and Hg, exceeding WHO limits. Biologically, the ethanol extract produced up to 99.74% larval mortality at 40–50 mg/mL (LC₅₀=8.58 mg/mL) and strongly inhibited egg laying (20.03% at 40 mg/mL). The study concludes that Tephrosia vogelii from Laikipia is a promising natural source of bioactive phytochemicals with potent acaricidal activity against Rhipicephalus sanguineus (R. sanguineus). It is recommended that future work focus on purifcation and fractionation of the ethanol extract to isolate key rotenoids and favonoids and develop standardized, environmentally safe formulations for tick control in livestock and integrated pest-management programs. 2026-05-01T00:00:00Z