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Synergistic use of nanoparticles and probiotic lactic acid bacteria in combating pathogens: mechanisms, applications and safety considerations
(Nano Plus: Sci. Technol. Nanomater., 2026-04-20) Oladipo, Christianah; Sangodare, A; Ogunsona, S; Fashogbon, Racheal; Ohijeagbon, O
The increasing threat of antimicrobial resistance (AMR) necessitates interest in the development of novel, highly potent, and biologically compatible methods for pathogen control. The combination of Probiotic Lactic acid bacteria and nanoparticles creates two different approaches that work together to achieve strong antimicrobial effects. Lactic acid bacteria (LAB) function as natural antagonists that produce strong antimicrobial substances, that include organic acids and bacteriocins and hydrogen peroxide, to create an environment that prevents other pathogens from growing. The nanoparticles (NPs), which include silver and iron oxide and zinc oxide, liposomes, selenium exhibit strong antibacterial properties because they induce cell death through their membrane destruction capabilities and ion discharge mechanisms and reactive oxygen species (ROS) generation. The integration of probiotic LAB with nanoparticles offers enhanced antimicrobial at lower dosages. However, challenges related to nanotoxicology, stability of probiotic nanoparticle systems, and clinical safety remain critical considerations. This
synergy approach represents a promising strategy for tackling AMR with potential applications in food safety and healthcare.
Green synthesis of selenium nanoparticles from Helianthus annuus leaf extracts: antioxidant and antimicrobial activities on foodborne pathogens
(Nano Plus: Sci. Technol. Nanomater, 2025-07-18) Fashogbon, Racheal; Akinade, K; Emozozo, O; Samson, Oyindamola; Adegbuyi, G; Oladipo, I
The increasing global demand for safer food and antibiotic resistant products has incited momentous interest in eco-friendly strategies for the control of foodborne pathogenic microbes. The conventional synthesis of selenium nanoparticles using chemicals is hazardous, energy-intensive, thereby raises environmental concerns. The green synthesis of Selenium nanoparticles (SeNPs) using Helianthus annuus provides a sustainable and effective platform for combating foodborne pathogens, owing to their low toxicity profile and multifaceted antimicrobial mechanisms. Helianthus annuus. This study, therefore, emphasized the green synthesis of selenium nanoparticles (SeNPs) from Helianthus annuus leaf extract using ethyl acetate (SeNPEa) and methanolic (SeNPM) extraction techniques, along with the antioxidant and antimicrobial activity of the resulting nanoparticles against foodborne pathogens. UV-Visible (UV-Vis), Fourier transform infrared (FT-IR), Energy Dispersive X-ray (EDX), Scanning Electron Microscopy (SEM), and X-ray Diffraction Techniques (XRD) were used to
characterize the SeNPs. The antioxidant and antibacterial potential of the synthesized SeNPs were evaluated. The two extracts showed no cardiac glucosides, and the existence of flavonoids, tannins, saponins, and steroids was observed. The extract changed the colour of the Se salt solution, with SeNPEaHa and SeNPMHa showing a maximum UV-Vis absorbance at 269 nm and 275 nm, respectively. The SEM analysis shows that the size of the SeNPEaHa and SeNPMHa at 10 and 20 µm. The quantitative analysis using EDX showed a high selenium content of 74.60% in SeNPEaHa and 72.12% in SeNPMHa. The functional groups, such as hydroxyl, alcohol, phosphate, and amine, were accountable for the capping and stabilization of nanoparticle proteins. The DPPH radical scavenging activity and reducing power scavenging assay contents of SeNPEaHa and SeNPMHa increased in a dose-dependent manner and were higher than those of ascorbic acid, used as a control. The SeNPEaHa and SeNPMHa were susceptible to Escherichia coli 700728, Staphylococcus aureus 6571, and Staphylococcus epidermidis. This result confirmed that Helianthus annuus is a potential biomaterial for synthesizing SeNPs, which can be exploited for its antioxidant and antibacterial activities.
ENHANCEMENT OF SOURDOUGH BREAD USING PROBIOTIC LACTIC ACID BACTERIA ISOLATED FROM CORN STEEP LIQUOR
(Journal of Faculty of Food Engineering, Ştefan cel Mare University of Suceava, Romania, 2025-02-27) Fashogbon, Racheal; Popoola, Bukola; Samson, Oyindamola; Akinwunmi, Ismail; Ojo-Omoniyi, Olusola
Fermented Zea mays (OGI), an edible paste made from fermented grains specific to the region, is an integral part of the human diet. Corn steeping liquor (CSL) is an important by-product obtained from the wet milling of Zea mays. The present study was conducted to investigate the probiotic characteristics and in vitro antibacterial activity of lactic acid bacteria (LAB) obtained from CSL, as well as their impact on the quality of sourdough bread. A total of 46 LAB were isolated and evaluated for their probiotic potential. The probiotic potential of LAB was determined by evaluating their hemolytic capacity, bile salt resistance, phenol tolerance, antimicrobial and antioxidant activities. The lactic acid bacteria with the most promising probiotic potential were molecularly characterized and
used for the production of sourdough bread (SDB). Conventional microbiological methods identified Lactobacillus plantarum (21%), Lactobacillus fermenti, and Leuconostoc mesenteroides (17%) as the predominant LAB species. Twelve LAB showed signs of gamma hemolysis. It is noteworthy that isolate CSL23 showed the highest bile tolerance, while isolates CSL15, CSL23, and CSL6 demonstrated the highest phenol tolerance. Isolates CSL15, CSL23, and CSL29 showed significant inhibition zones of 15.00 ± 0.18 mm, 20.5 ± 0.26 mm, and 22.60 ± 0.31 mm against four tested pathogens, in addition to effective antioxidant scavenging activity. Molecular identification revealed that LAB isolates CSL15, CSL23, and CSL29 were Lactiplantibacillus plantarum ROF4, Lactiplantibacillus plantarum ROF5, and Lactiplantibacillus plantarum ROF6, respectively. This finding indicates that all LAB strains belong to the same genus. Therefore, it is evident that the current study demonstrated that Lactiplantibacillus plantarum strains isolated from CSL have the potential to serve as promising probiotic starter cultures that could be used in the production of sourdough bread with improved functional properties.
Phytochemical and Antimicrobial Potentials of Aqueous Leaves Extracts of Helianthus annuus (Sunflower): A Natural Preservative in Food Industry
(Greener Journal of Agricultural Sciences, 2025-07-18) Fashogbon, Racheal; Aforijiku, Samuel; Adegbuyi, Gbemisola; Akinola, T
Helianthus annuus (sunflower) is an important plant that belongs to the family Asteraceae and usually used as oil in the food industry. This study investigates the phytochemical and antimicrobial potentials of aqueous leaf extracts from Helianthus annuus (AqHa). The H.annuus leaves were collected from botanical section of Ajayi Crowther University, Oyo and were taken to the laboratory and processed into aqueous extract using standard method. The Aqueous leaf extracts from Helianthus annuus (AqHa) were assessed for phytochemical attributes, Fourier transform infrared Spectroscopy (FTIR), antioxidant activity and
antimicrobial potential against food pathogens using standard procedures. Phytochemical analysis of the assessed extracts revealed the presence of some plant metabolites including flavonoids, steroid, tannins and saponins while FTIR showed the presence of some key functional groups such as O-H stretch, H-bonded, O-H stretch, H-bonded, Methylene C-H stretch, Methyne C-H stretch and C=C Conjugated bonds. The peak at 2355.00 cm1 and 1735.60 cm1 were related to stretch vibration of Methylene C-H and C=C, respectively both denoting the presence of fat while the highest peak (3759.57 cm-1) was related to hydroxyl group. AqHa had the highest zone of inhibition (13 mm) against Staphylococcus aureus while the least (7 mm) inhibition was on Staphylococcus spp. The highest antioxidant activity was evaluated as Hydrogen peroxide scavenging assay (56 and 87%) and reducing power scavenging assay (49% and 83%). Aqueous leaf extracts from Helianthus annuus (AqHa) contains phytochemical compounds, had antioxidant activity and antimicrobial potentials on food pathogens, and
could be used as an alternative in the development of plant based antimicrobials or as preservatives in food industries.
Screening and Molecular Identification of Biosurfactant-Producing Bacteria Isolated from Contaminated Soil and Vegetables in Ago-Iwoye, Nigeria
(ASRIC Journal on Natural Sciences, 2024) Samson, Oyindamola; Fashogbon, Racheal; Okonkwo, Chikezie; Adeyemi, Jamiu; Adekola, Hafees; Makanjuola, Stephen; Salisu, Titilola; Aina, Sulaiman; Kazeem, Muinal; Onajobi, Ismail
Biosurfactants play a crucial role in bioremediation processes, wherein bacteria producing these surfactants utilize contaminants or pollutants as energy and nutrient sources. This study aims to screen and molecularly identify bacteria recovered from soil contaminated by cassava effluent and various vegetables for biosurfactant production. Standard methods were used for bacterial counting, isolation, and identification. Blood hemolysis and oil spreading tests evaluated biosurfactant production. High producers were characterized by 16S rRNA sequencing. Mean values compared and significance tested using chi-square. The mean bacterial counts were 67.00±2.54 for Ago-Iwoye soil, 86.00±4.35 or Oru soil, 102.00±3.32 for Ago-Iwoye vegetables, and 109.00±4.83 for Oru vegetables. Isolates AS1, AS2, CSA34, CSA36, CSO48, CSO49 showed partial hemolysis (10.00 – 14.00 mm), while others exhibited complete hemolysis (Isolates FP11, LS15, CSO45). Isolate LS30 showed no hemolytic activity. Among the isolates tested, only LS15 and CSO45 exhibited positive oil spreading ability, with diameters of 5.00 ± 2.50 mm and 7.50 ± 3.54 mm, respectively. Staphylococcus aureus and Bacillus spp. proved to be the highest biosurfactant producer by showing better results. The molecular characterization of the identified isolate LS15 revealed a 100% match with Staphylococcus aureus 8 BWI (accession number KX456108.1), while isolate CSA45 was identified as Bacillus marasmi with 96.6% similarity (accession number NR_147397.1). Therefore, sustained attention to Staphylococcus spp. and Bacillus spp. is warranted, given their consistent success in screening tests as proficient biosurfactant producers.