Collins Onohuomhen EBIAGUANYE

Environmental pollution is a growing concern, with its detrimental effects on ecosystems, biodiversity, and human health. Spent lubricating oil (SLO) represents a pervasive environmental pollutant, often finding its way into soil and posing a significant threat to plant life. In this comprehensive study, we delve into the intricate dynamics between SLO and soybean (Glycine max) seedlings during the early germination phase, with a specific focus on evaluating the impact on Total Antioxidant Property (TAP), Total Flavonoid Content (TFC), and Total Phenolic Content (TPC) after 14 days of germination. The investigation entailed the examination of four distinct SLO fractions: the aqueous extract, the water-insoluble fraction extract, the water-soluble fraction extract, and the whole SLO extract. The determination of TAP was executed using gallic acid as a standard, revealing that the water-insoluble fraction extract exhibited the highest TAP (40.00 mgGAE/g), outperforming both the whole SLO extract (30.00 mgGAE/g) and the water-soluble fraction extract (16.00 mgGAE/g). This discrepancy in TAP among the various SLO fractions suggests that specific components within SLO have varying effects on soybean seedlings' antioxidant defense mechanisms. Furthermore, the assessment of TPC unveiled a nuanced picture, with the water-insoluble fraction extract (28.00 mgGAE/g) displaying a notably elevated concentration of phenolic compounds in comparison to the whole SLO extract (16.00 mgGAE/g) and the water-soluble fraction extract (24.00 mgGAE/g). The disparities in TPC emphasize the selective influence of different SLO components on the production of phenolic compounds, which are crucial for plant defense mechanisms against oxidative stress. Turning our attention to TFC, using quercetin as a standard, the whole SLO extract (32.00 mgQE/g) exhibited the highest flavonoid content, surpassing both the water-insoluble fraction extract (24.00 mgQE/g) and the water-soluble fraction extract (12.00 mgQE/g). This observation suggests that certain elements within SLO might trigger the biosynthesis of flavonoids, essential compounds for plants in mitigating the harmful effects of oxidative stress. In conclusion, the findings from this meticulous investigation underscore the intricate and multifaceted nature of plant-pollutant interactions. Each fraction of SLO exerts a unique and context-dependent influence on soybean seedlings' biochemical properties, with profound implications for antioxidant defenses, phenolic compounds, and flavonoids. This study highlights the critical importance of adopting a tailored and precise approach when evaluating the effects of pollutants on plant biochemistry