The results of this study demonstrate that the selected oils exhibited varying levels of antimicrobial activity. Overall, most of the tested organisms were sensitive to the oils, including Calotropis procera, Chia, Moringa, Neem, Black seed, and Wheat germ, all of which displayed moderate to strong antimicrobial and antioxidant properties. However, most of the oils tested showed limited or weak prebiotic effects on the probiotic strains examined. In contrast, the mixture of oils exhibited superior antimicrobial, antioxidant, and prebiotic activities compared to each oil. Among the oils tested, Chia seed oil exhibited the strongest anticoagulant activity, ranking second only to Calotropis procera oil in terms of fibrinolytic activity. This finding aligns with Oliva et al. (2021), who noted that chia seed supplementation serves as an effective functional food and dietary strategy for preventing or reversing atherothrombotic cardiovascular disorders and liver fibrosis. Their research demonstrated that feeding rats a chia seed-enriched diet for three months reversed several diet-induced diseases, including dyslipidemia, visceral adiposity, and insulin resistance. Additionally, they observed normalization of platelet counts, coagulation parameters, and plasma fibrinogen levels in these animals. Our findings are also consistent with Ozón et al. (2022), who reported antioxidant, anticoagulant, and antithrombotic activities of chia seeds and their by-products against both intrinsic and extrinsic coagulation pathways. However, it is noteworthy that Ozón et al. (2022) did not detect antioxidant activity in chia seed oil in their study. Chia seed oil demonstrated significant antimicrobial activity, corroborated by other studies (Elshafie et al., 2018; Parker et al., 2018). Furthermore, various reports have documented the antifungal and antibacterial properties of different chia seed products, such as mucilage (Muñoz-Tébar et al., 2022; Cacciatore et al., 2022). Our results are comparable to those of Knez et al. (2019), who highlighted chia's substantial antimicrobial capacity, likely attributed to its high linolenic acid (C18:3) content (56.15%). However, Chia seed oil exhibited a weak prebiotic effect on two strains of Lactobacillus, L. casei and L. helveticus, while showing no effect on L. reuteri.
Among all six oils tested, Calotropis procera oil demonstrated maximum antioxidant and antimicrobial activity against the tested bacterial strains. This efficacy may be linked to its high oleic acid (C18:1) and linoleic acid (C18:2) content (37.73% and 33.72%, respectively), which are well-known for their antibacterial properties (Dilika et al., 2000; Huang et al., 2010; Petropoulos et al., 2021) as well as their antioxidant activity in medicinal plants and seeds (Saini et al., 2017; Türkekul et al., 2017; Song et al., 2021). However, it was ineffective against the tested fungus (Aspergillus niger). Our findings align with Amini et al. (2021), who reported significant antibacterial activity from C. procera extracts, as well as with Yesmin et al. (2008), who documented its antioxidant activity through DPPH radical scavenging assays. The present study's findings regarding C. procera are consistent with research conducted by Al-Rowaily et al. (2020), which indicated that essential oil from C. procera exhibited antibacterial activity against various bacteria and fungi. Conversely, this oil showed no prebiotic activity on the tested Lactobacillus strains in our study. Notably, Calotropis procera oil proved to be a strong anticoagulant, second only to Chia seed oil. It also exhibited greater fibrinolytic activity than Chia seed oil. This is supported by Omar et al. (2023), who reported concentration-dependent anticoagulant activity from various extracts of Calotropis procera, suggesting inhibitory effects on clotting factors within both intrinsic and extrinsic pathways. When compared to the positive control heparin, Calotropis procera oils demonstrated relatively good prothrombin time (PT) values (18 ± 0.15 seconds) and longer clotting times (120 s.).
Our findings revealed that Calotropis procera oil exhibited the most significant antimicrobial activity against the tested bacterial strains, followed by Chia seed oil. This strong antimicrobial effect may be attributed to the presence of specific bioactive compounds in these oils. Calotropis procera oil contains various cardenolides, alkaloids, and terpenoids (Singh et al., 2024). These compounds are known for their ability to disrupt bacterial cell membranes, inhibit protein synthesis, and interfere with essential metabolic processes (Ahmad Nejhad et al., 2023). Specifically, cardenolides can inhibit the Na+/K+-ATPase pump in bacterial cell membranes, leading to cell death (Yang et al., 2018). The higher concentration of these potent compounds in Calotropis procera oil likely contributes to its superior antimicrobial efficacy compared to other oils tested.
Chia seed oil, while less potent than Calotropis procera oil, also demonstrated significant antimicrobial activity. This activity may be due to its high content of α-linolenic acid (ALA), a polyunsaturated fatty acid, and other phenolic compounds such as chlorogenic acid, caffeic acid, and myricetin (Mettwally et al., 2022). ALA has been shown to disrupt bacterial membrane integrity and inhibit the growth of various pathogens (Casillas-Vargas et al., 2021). Furthermore, the phenolic compounds present in chia seed oil can inhibit bacterial enzymes involved in cell wall synthesis and energy production, leading to growth inhibition (Abdel-Aty et al., 2021). The synergistic effect of ALA and phenolic compounds likely contributes to the observed antimicrobial activity of chia seed oil.
The antioxidant activity was highest in Calotropis procera and Wheat germ oils, suggesting the presence of potent radical scavenging compounds. Calotropis procera oil is known to contain various phenolic compounds, flavonoids, and terpenoids (Ahmad Nejhad et al., 2023; El-Hadad et al., 2024). Flavonoids act as antioxidants by donating electrons or hydrogen atoms to stabilize free radicals, thereby preventing oxidative damage to cellular components (Panche et al., 2016). Terpenoids also contribute to antioxidant activity through similar mechanisms and by enhancing the activity of endogenous antioxidant enzymes (Kobayashi et al., 2025). The high antioxidant activity of Calotropis procera oil can therefore be attributed to the combined effect of these various antioxidant compounds.
Wheat germ oil is a rich source of vitamin E (tocopherols), particularly alpha-tocopherol, and also contains other antioxidants such as carotenoids and ferulic acid (El-Hadad et al., 2024). Alpha-tocopherol is a well-known chain-breaking antioxidant that protects cell membranes from lipid peroxidation by scavenging lipid peroxyl radicals (Burton et al., 1985). Carotenoids and ferulic acid also contribute to the overall antioxidant capacity of wheat germ oil by neutralizing free radicals and reducing oxidative stress (Kobayashi et al., 2025). The high concentrations of these antioxidants in wheat germ oil likely explain its strong antioxidant activity observed in this study."
Meanwhile, Moringa oil displayed good antimicrobial activity against all the tested pathogens except for Pseudomonas aeruginosa. This observation is consistent with findings from Lalas et al. (2012) and Sharma et al. (2019), which recognized the antimicrobial properties of Moringa oils. Chuang et al. (2007) also reported antifungal properties associated with Moringa essential oil. The strong antimicrobial activity of Moringa oil can be attributed to its high oleic acid content (74.26%), a fatty acid recognized for its antimicrobial properties (Rahdar et al., 2020; Ghavam et al., 2021; Ghavam et al., 2022). However, both its antioxidant and anticoagulant activities were found to be lower than those of other tested oils. De Andrade Luz et al. (2012) identified carbohydrate recognition proteins known as lectins that act as anticoagulant proteins affecting in vitro blood coagulation parameters by interacting through a carbohydrate recognition domain. Previous studies have reported fibrinolytic activities associated with aqueous extracts of Moringa oleifera leaves and roots (Satish et al., 2012). Interestingly, no prebiotic effect was observed from Moringa oil on the tested Lactobacillus strains in this study. This finding contrasts with Wang et al. (2019), who suggested that polysaccharides derived from Moringa oleifera leaves might serve as promising prebiotics with health benefits when tested in vivo on ICR mice. The discrepancy may arise from differences in the parts of Moringa oleifera that were tested; our study focused on seed oil rather than leaf powder. Furthermore, the prebiotic tests conducted here were performed in vitro rather than in vivo. Neem oil demonstrated good antimicrobial activity but failed to affect Aspergillus niger. This observation aligns with findings from Elavarasu et al. (2012) and SaiRam et al. (2000), who reported high antimicrobial properties associated with neem oil.
Additionally, Blum et al. (2007) found that neem oil extract exhibited substantial bactericidal effects against Helicobacter pylori, while Gupta and Bhat (2016) noted its antibacterial effects against methicillin-resistant Staphylococcus aureus (MRSA). Our results indicate that neem oil possesses strong antioxidant and anticoagulant activities; however, its fibrinolytic activity was found to be weak. These findings are supported by Rinaldi et al. (2017), who recorded significant antioxidant activity from neem oil nanoemulsions using DPPH and ABTS assays, as well as by Sani et al. (2022), who documented higher free radical scavenging activities for neem seed oil compared to flower extracts. Furthermore, Nahak and Sahu (2011) indicated that neem seed oil contains high levels of total phenolic compounds responsible for inhibiting DPPH radicals effectively. They also noted potential health benefits for incorporating neem flower and seed oils into human diets as healthy supplements for both diabetics and the general population due to their antioxidant potential for use in pharmaceuticals. The anticoagulant properties of neem oil have been previously reported by Mani et al. (2018), highlighting its applications in wound healing processes as well. On the other hand, neem seed oil did not exhibit any prebiotic activity on the tested Lactobacillus strains in this study; this finding contradicts results reported by Rehman et al. (2023), where neem herbal extract positively influenced intestinal microbial populations in broiler chicks when incorporated into their diet by increasing Lactobacillus content while decreasing E. coli levels.
The observed enhanced prebiotic activity of the oil mixture compared to individual oils suggests a synergistic effect in promoting the growth of beneficial bacteria. The mixture provides a diverse array of fatty acids and bioactive compounds that can selectively stimulate the growth of Lactobacillus strains. For example, specific fatty acids in chia seed oil and moringa oil may serve as preferential carbon sources for Lactobacillus species, while other compounds such as phenolic acids in black seed oil, may enhance their metabolic activity (Zeng et al., 2024). Additionally, the combination of different oils may create a more favorable microenvironment in the gut, promoting the colonization and growth of beneficial bacteria while inhibiting the growth of pathogens. Further studies are needed to identify the specific components responsible for the observed prebiotic activity and to elucidate the exact mechanisms by which they promote the growth of Lactobacillus strains.
Black seed oil showed a moderate prebiotic effect on Lactobacillus casei but had no impact on the other two Lactobacillus strains tested. These findings are consistent with reports from Kooti et al. (2016) and Mohammed et al. (2019), which highlighted the antimicrobial properties of black seed oil. Furthermore, Salman et al. (2016) demonstrated that black seed oil possesses antibacterial effects against multidrug-resistant bacteria; this antimicrobial capacity is attributed to its high linoleic acid (C18:2n6c) and oleic acid (C18:1n9c) content active components previously documented in black seed oils (Rahim et al., 2022; Joujou et al., 2024). In our study, the linoleic acid content in black seed oils was significantly higher than that found in all other tested oils at 55.66%. Our results align with Tiji et al.'s findings from 2021 that linked the antibacterial effects of Moroccan Nigella sativa seed extracts to fatty acids such as linoleic acid and palmitic acid. Notably, black seed oil exhibited the weakest antioxidant activity among all six oils tested, along with weak fibrinolytic activity despite its strong anticoagulant properties. These observations are consistent with Yusof et al., (2017) regarding Nigella sativa seed extract's potent anticoagulant effects Al-Jishi and Hozaifa, (2003). Additionally, indicated strong anticoagulant effects associated with Nigella sativa when administered to adult male albino rats at varying doses over four weeks. Other recent studies have reported the hematological effect of Nigella sativa (Benjamin, 2025; Chad, 2025; Ozsan et al., 2024). Awad et al. (2005) suggest a concentration-dependent role for black seed oil in modulating fibrinolysis/thrombus formation through influencing endothelial cell fibrinolytic potential. Conversely, Awad et al. (2005) earlier work indicated that black seed oil decreased fibrinolytic potential in vitro within human fibrosarcoma cell lines (HT1080), suggesting possible mechanisms for inhibiting local tumour metastasis.
Lastly, wheat germ oil demonstrated the lowest fibrinolytic activity among all tested oils while exhibiting moderate anticoagulant effects alongside strong antioxidant properties against all microorganisms evaluated consistent with Kim et al.'s findings from 2010 regarding wheat germ extract's antimicrobial properties. GC-MS analysis revealed relatively high contents of oleic acid and linoleic acid at 24.03% and 53.63%, respectively—both recognized for their antibacterial activities, as previously mentioned. Moreover, Mahmoud et al.'s research from 2015 noted strong antibacterial effects associated with defatted wheat germ extracts. Wheat germ oil emerged as an effective stimulant for promoting growth among prebiotic bacteria such as L. reuteri while showing no impact on the other two Lactobacillus species evaluated. In summary, regarding anticoagulant activities among these oils, both chia seed oil, followed closely by calotropis procera, exhibited robust effects while moringa oil displayed minimal impact overall; calotropis procera also showcased superior fibrinolytic capabilities, followed by chia seed oil, whereas wheat germ demonstrated weaker activities across these parameters highlighting their potential applications across various health-related fields.
The observed increase in both antioxidant activity (AA) and total phenolic content (TPC) in the fortified yoghurt can be attributed to the bioactive peptides naturally present in milk (Korhonen & Pihlanto, 2020), as well as the incorporation of a multifunctional oil (MO) blend. This blend, comprising Calotropis procera oil, chia seed oil, moringa oil, neem oil, black seed oil, and wheat germ oil, provides a rich source of antioxidants and phenolic compounds, contributing synergistically to enhancing the yoghurt’s overall antioxidant capacity (Usmani et al., 2023; Ixtaina et al., 2022; Rani et al., 2018). Unlike previous studies that have focused on individual oils, this research explores the combined effect of a diverse oil blend, potentially offering a more effective strategy for enhancing functional properties in dairy products (Sharma et al., 2023).
Each oil within the blend possesses a unique phenolic profile. Calotropis procera oil, despite its relatively low phenolic content, contains phenolic acids such as P-coumaric acid and flavonoids like catechin and rutin, which have demonstrated significant antioxidant potential (Usmani et al., 2023). Chia seed oil is particularly rich in chlorogenic acid, caffeic acid, myricetin, quercetin, and kaempferol, contributing to its strong antioxidant activity (Ixtaina et al., 2023). Moringa oil enhances the mixture with Gallic acid, chlorogenic acid, ellagic acid, and flavonoids, which are known for their free radical scavenging properties (Rani et al., 2018). Neem oil contributes additional antioxidant compounds, including nimbin, quercetin, and Gallic acid ( Ni Putu Ratna et al., 2024). Black seed oil, recognized for its health-promoting properties, is rich in thymoquinone, carvacrol, t-anethole, and 4-terpineol, which significantly enhance antioxidant activity (Soleimanifar et al., 2019). Lastly, wheat germ oil further strengthens the blend’s antioxidant capacity with ferulic acid, vanillic acid, p-hydroxybenzoic acid, and flavonoids such as apigenin and luteolin ( Mohammed et al., 2023).
The combination of these oils results in an amplified antioxidant effect due to the complementary actions of their diverse phenolic compounds. The synergistic interactions among these bioactive components effectively scavenge free radicals, mitigate oxidative stress, and provide enhanced cellular protection. Furthermore, phenolic compounds are known to modulate enzymatic antioxidant systems. The presence of this oil blend may have contributed to the upregulation of endogenous antioxidant enzymes such as catalase and superoxide dismutase during storage, further enhancing the stability of antioxidant activity.
Over the storage period, a progressive increase in both AA and TPC was observed, particularly by the 21st day (Fig. 2). This increase may be attributed not only to the activation of enzymatic antioxidants but also to potential interactions between phenolic compounds and milk proteins, which could enhance their bioavailability (Stobiecka et al., 2022). A similar trend was reported by Kang et al., (2018), who found that the AA of yogurt increased significantly with the addition of red or green pepper juice, establishing a direct correlation between AA levels and TPC (Kang et al., 2018).
From a functional perspective, the fortification of yoghurt with this oil blend not only enhances its nutritional value but may also influence sensory attributes such as texture and flavor (Shiby & Mishra, 2013). While previous studies have reported that high levels of phenolic compounds can lead to bitterness or astringency (Buitimea-Cantúa et al., 2018), the balanced formulation of this oil blend likely minimizes undesirable effects while maximizing health benefits. The incorporation of plant-based bioactive compounds has been shown to improve not only antioxidant potential but also extend the shelf-life of dairy products by reducing lipid oxidation and microbial spoilage (Ali et al., 2022). Future research should focus on consumer acceptability studies and the potential impact of this oil blend on gut microbiota, as phenolic-rich ingredients have been shown to modulate intestinal microbial composition and promote the growth of beneficial bacteria (Loo et al., 2020), further validating its functional food applications.
This study highlights the diverse health benefits of various seed oils, including Calotropis procera, Chia, Moringa, Neem, Black seed, and Wheat germ, emphasizing their potential applications in functional foods. The oils demonstrated varying levels of antimicrobial, antioxidant, anticoagulant, and prebiotic activities, with Chia seed oil exhibiting the strongest anticoagulant properties and significant antimicrobial effects. Conversely, Calotropis procera oil showed the highest antioxidant and antimicrobial activities, making it a promising candidate for health enhancement. While most oils displayed weak prebiotic effects on tested probiotic strains, the mixture of oils demonstrated superior activity across all evaluated parameters. Additionally, the findings indicate that Moringa oil possesses notable antimicrobial properties but limited anticoagulant effects, while Neem oil exhibited strong antioxidant and antimicrobial activities. Notably, Black seed oil showed robust anticoagulant properties despite its weaker antioxidant and fibrinolytic activities. The study underscores the potential of these seed oils as functional food ingredients that can contribute to improved health outcomes through their bioactive compounds. Future research should further explore the mechanisms underlying these effects and investigate the practical applications of these oils in dietary interventions for enhanced health benefits.