Watercress oil loaded with gel: evaluation of hemolysis inhibition, antioxidant, antimicrobial, and healing properties

Abstract

Plant-derived compounds are renowned for their remarkable pharmacological properties, holding immense promise for therapeutic interventions in human health. In this study, we aimed to assess the antimicrobial, anti-hemolytic, antioxidant, and wound healing attributes of watercress oil incorporated into Vaseline gel (OLG) compared to watercress oil alone. OLG was formulated through a meticulous process involving the addition of Vaseline gel to the oil under agitation conditions. High-performance liquid chromatography analysis of watercress oil unveiled a rich array of phenolic compounds, including gallic acid (10.18 μg/mL), daidzein (3.46 μg/mL), and hesperetin (3.28 μg/mL). The inhibitory zones caused by watercress oil alone against a spectrum of pathogens, including Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis, and Candida albicans, were measured at 25 ± 0.3, 26 ± 0.1, 22 ± 0.2, 25 ± 0.2, and 24 ± 0.1 mm, respectively. Notably, OLG exhibited slightly larger zones of inhibition (27 ± 0.2, 30 ± 0.2, 24 ± 0.1, 28 ± 0.1, and 25 ± 0.3 mm) against the same microbial strains. Furthermore, the minimum inhibitory concentration (MIC) of OLG against E. coli and E. faecalis was lower compared to watercress oil alone, indicating enhanced efficacy. Similarly, the minimum bactericidal concentration (MBC) of OLG was notably lower across all tested bacteria compared to watercress oil alone. Inhibition of bacterial hemolysis, particularly K. pneumoniae, was significantly enhanced with OLG treatment, showcasing reductions of 19.4%, 11.6%, and 6.8% at 25%, 50%, and 75% MIC concentrations, respectively, compared to watercress oil alone. The antioxidant activity of both oil and OLG was quantified with IC50 values of 2.56 and 3.02 μg/mL, respectively. Moreover, OLG demonstrated remarkable efficacy in wound healing assays, with notable enhancements in migration rate, wound closure, and area difference compared to control cells. In light of the observed antibacterial, antifungal, anti-hemolytic, and wound healing properties of OLG, this formulation holds therapeutic potential in treating microbial infections and promoting wound healing.

Keywords: anti-hemolysis; antimicrobial; antioxidant; vaseline gel; watercress oil.

FIGURE 1

Chromatogram analysis for phenolic constituents of watercress oil by High-performance liquid chromatography (HPLC).

FIGURE 2

In-vitro inhibition (inhibitory zones) of microbial growth caused by negative control dimethyl sulfoxide (DMSO) (1), positive control (Gentamicin for bacteria and clotrimazole for fungi) (2), Vaseline gel (3), watercress oil (4), and watercress oil loaded with Vaseline gel (OLG) (5).

FIGURE 3

Inhibition rate of multiple Gram-positive and negative bacterial hemolytic activities at different doses/concentrations (0% MIC, 25% MIC, 50% MIC, and 75% MIC) of watercress oil (Oil) and watercress oil loaded with Vaseline gel (OLG). Error bars in the Figure represent the calculated standard deviation (SD).

FIGURE 4

Visual observation of multiple bacterial hemolytic activities treated with different MIC concentrations of watercress oil loaded with Vaseline gel (OLG) and watercress oil only. Tube 2, 3, 4 treated with 25%, 50% and 75% MIC, respectively while tube 1 is the negative control (SDS), and tube 5 is the tested bacterium only (untreated). Anti-hemolytic activity for watercress oil and OLG in presence of Klebsiella pneumoniae (A, B), Escherichia coli (C, D), Staphylococcus aureus (E, F) and Enterococcus faecalis (G, H).

FIGURE 5

Antioxidant activity of watercress oil (Oil), watercress oil loaded with Vaseline gel (OLG), Vaseline gel (G), and ascorbic acid. Error bars in the figure represent the calculated standard deviation (SD). IC₅₀ stands for Half-maximal inhibitory concentration.

FIGURE 6

Scratch assessment assay to evaluate the influence of watercress oil loaded with Vaseline gel (OLG) towards cells on the area of wound at different time of exposures (0 and 48 h). Negative control (Untreated cells) was included for comparison.