Browsing by Author "Patrick Ssebugere"

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    Polycyclic aromatic hydrocarbons in breast milk of nursing mothers: Correlates with household fuel and cooking methods used in Uganda, East Africa
    (Elsevier Ltd, 2024-06) Fred Ssepuya; Silver Odongo; Benjamin A. Musa Bandowe; Juma John Moses Abayi; Chijioke Olisah; Henry Matovu; Edward Mubiru; Mika Sillanpää; Ibrahim Karume; Charles Drago Kato; Victor Odhiambo Shikuku; Patrick Ssebugere
    Maternal breast milk, which is a complete food for the infant's growth, development, and health, contains fats and lipids making it susceptible to accumulation of lipophilic compounds like polycyclic aromatic hydrocarbons (PAHs). This study aimed at analyzing correlates of measured levels of PAHs in breast milk of nursing mothers to frequently used household fuels and cooking methods in Uganda, and estimate the potential health risks of PAHs to infants through breastfeeding. Sixty breast milk samples were collected from healthy and non-smoking mothers who had lived in Kampala capital city (urban area) and Nakaseke district (rural area) for at least five years. Sample extracts were analyzed for PAHs using a gas chromatograph coupled with a triple quadrupole mass spectrometer. ∑13PAHs in samples from Kampala ranged from 3.44 to 696 ng/g lw while those from Nakaseke ranged from 0.84 to 87.9 ng/g lw. PAHs with 2–3 rings were more abundant in the samples than PAHs with 4–6 rings. At least 33 % of the variance in the levels of ∑13PAHs in the breast milk samples was attributable to the fuel type and cooking methods used. Nursing mothers who used charcoal for cooking accumulated higher levels of ∑13PAHs in their breast milk samples compared to those who used firewood. Levels of ∑13PAHs in breast milk of mothers increased depending on the cooking methods used in the order; boiling< grilling< deep-frying. In all samples, hazard quotients for PAHs were <1 and estimated incremental cancer risks were all between 10−6 and 10−4 , indicating that the health risks to infants due to the ingestion of PAHs in breast milk was tolerable. Further studies with large datasets on PAHs and their deriv atives and, larger samples sizes are needed to confirm these findings.
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    Response surface methodology directed modeling of the biosorption of progesterone onto acid activated Moringa oleifera seed biomass: Parameters and mechanisms
    (Elsevier Ltd, 2024-05) Emily Ngeno; Roselyn Ongulu; Victor Shikuku; Deo Ssentongo; Benton Otieno; Patrick Ssebugere; Francis Orata
    In this study, chemically activated fat-free powdered Moringa oleifera seed biomass (MOSB) was synthesized, characterized, and utilized as a cost-effective biosorbent for the abstraction of progesterone (PGT) hormone from synthetic wastewater. Natural PGT is a human steroid hormone from the progestogen family. Synthetic PGT is approved for the regulation of the menstrual cycle, aiding contraception, and is administered as a hormone replacement therapy in menopausal and post-menopausal women. PGT is an endocrine disrupting chemical (EDC) with negative health impacts on biota. The X-ray diffractogram (XRD), Scanning electron microscopy Energy-dispersive X-ray spectroscopy (SEM-EDS), and Brunauer–Emmet–Teller (BET) analyses displayed a porous, amorphous biosorbent with an elemental composition of 72.5% carbon and 22.5% oxygen and a specific surface area of 210.0 m2 g− 1 . The process variables including temperature (298–338 K), pH (2–10), contact time (10–180 min), adsorbate concentration (20–500 μg L− 1 ), and adsorbent dosage (0.1–2.0 g) were optimized using response surface methodology (RSM) to obtain the greatest efficacy of MOSB during biosorption of PGT. The optimum parameters for PGT biosorption onto MOSB were: 86.8 min, 500 μg L− 1 adsorbate concentration, 298 K, and 0.1 g adsorbent dosage. PGT removal from aqueous solutions was pH-independent. The Langmuir isotherm best fitted the equilibrium data with maximal monolayer biosorption capacity of 135.8 μg g− 1 . The biosorption rate followed the pseudo-first-order (PFO) kinetic law. The thermodynamic functions (ΔG < 0, ΔH = − 9.258 kJ mol− 1 and ΔS = +44.16 J mol− 1 ) confirmed that the biosorption of PGT onto MOSB is a spontaneous and exothermic process with increased randomness at the adsorbent surface. The biosorption mechanism was physisorption and was devoid of electrostatic interactions. The findings from this study indicate that MOSB is an inexpensive, low-carbon, and environmentally friendly biosorbent that can effectively scavenge PGT from aqueous solutions.
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    Response surface methodology directed modeling of the biosorption of progesterone onto acid activated Moringa oleifera seed biomass: Parameters and mechanisms
    (Elsevier Ltd, 2024-07-27) Emily Ngeno; Roselyn Ongulu; Victor Shikuku; Deo Ssentongo; Benton Otieno; Patrick Ssebugere; Francis Orata
    In this study, chemically activated fat-free powdered Moringa oleifera seed biomass (MOSB) was synthesized, characterized, and utilized as a cost-effective biosorbent for the abstraction of progesterone (PGT) hormone from synthetic wastewater. Natural PGT is a human steroid hormone from the progestogen family. Synthetic PGT is approved for the regulation of the menstrual cycle, aiding contraception, and is administered as a hormone replacement therapy in menopausal and post-menopausal women. PGT is an endocrine disrupting chemical (EDC) with negative health impacts on biota. The X-ray diffractogram (XRD), Scanning electron microscopy-Energy-dispersive X-ray spectroscopy (SEM-EDS), and Brunauer–Emmet–Teller (BET) analyses displayed a porous, amorphous biosorbent with an elemental composition of 72.5% carbon and 22.5% oxygen and a specific surface area of 210.0 m2 g−1. The process variables including temperature (298–338 K), pH (2–10), contact time (10–180 min), adsorbate concentration (20–500 μg L−1), and adsorbent dosage (0.1–2.0 g) were optimized using response surface methodology (RSM) to obtain the greatest efficacy of MOSB during biosorption of PGT. The optimum parameters for PGT biosorption onto MOSB were: 86.8 min, 500 μg L−1 adsorbate concentration, 298 K, and 0.1 g adsorbent dosage. PGT removal from aqueous solutions was pH-independent. The Langmuir isotherm best fitted the equilibrium data with maximal monolayer biosorption capacity of 135.8 μg g−1. The biosorption rate followed the pseudo-first-order (PFO) kinetic law. The thermodynamic functions (ΔG < 0, ΔH = −9.258 kJ mol−1 and ΔS = +44.16 J mol−1) confirmed that the biosorption of PGT onto MOSB is a spontaneous and exothermic process with increased randomness at the adsorbent surface. The biosorption mechanism was physisorption and was devoid of electrostatic interactions. The findings from this study indicate that MOSB is an inexpensive, low-carbon, and environmentally friendly biosorbent that can effectively scavenge PGT from aqueous solutions. [Display omitted] •MOSB has been used in sequestration of progesterone (PGT) from solution.•Optimum adsorbate parameters were 86.8 min, 500 μg L−1, 298 K and 0.1 g dosage.•PGT removal from aqueous solutions was pH independent.•Biosorption of PGT onto MOSB was a spontaneous and exothermic process.•Biosorption mechanism was physisorption and devoid of electrostatic interactions.