The Effect of Commercial Cannabidiol (CBD) Tinctures on Fusarium oxysporum

School Name

Spring Valley High School

Grade Level

10th Grade

Presentation Topic

Microbiology

Presentation Type

Non-Mentored

Abstract

Fusarium oxysporum is a globally destructive plant pathogen that causes wilt disease and significant agricultural losses. As resistance to chemical fungicides continues to rise, natural plant-derived antimicrobials, such as cannabidiol (CBD), have emerged as promising alternatives due to their reported antifungal properties (Cárdenas-Laverde et al., 2021). The purpose of this study was to evaluate whether two commercially available CBD tinctures (50 mg/mL and 300 mg/mL) could inhibit the growth of F. oxysporum. It was hypothesized that CBD would inhibit fungal growth in a concentration-dependent manner, with the 300 mg/mL tincture producing the largest zone of inhibition (ZOI). Using an agar diffusion assay, sterile PDA (potato dextrose agar) plates were inoculated with F. oxysporum and treated with disks soaked in lab-grade water, 50 mg/mL CBD, or 300 mg/mL CBD. Plates were incubated, and ZOIs were measured over four days. The 50 mg/mL CBD treatment produced some antifungal activity across all four days, while the 300 mg/mL CBD tincture showed little antifungal activity on the first day and none afterwards. A one-way ANOVA revealed significant differences among treatment groups (Day 1: F(2, 87) =5.88, p=0.004) driven almost entirely by the inhibitory activity in the 50 mg/mL plates. Tukey post-hoc tests showed that the 50 mg/mL group differed from the others, while the 300 mg/mL tincture barely differed from the sterile control. These findings indicate that CBD can inhibit F. oxysporum, but higher concentrations or flavored tinctures may lose antifungal activity, likely due to added carrier ingredients or the nature of the concentration. CBD, therefore, shows potential as a natural antifungal agent, but formulation plays a critical role in determining its effectiveness.

Location

Furman Hall 111

Start Date

3-28-2026 11:00 AM

Presentation Format

Oral and Written

Group Project

No

COinS
 
Mar 28th, 11:00 AM

The Effect of Commercial Cannabidiol (CBD) Tinctures on Fusarium oxysporum

Furman Hall 111

Fusarium oxysporum is a globally destructive plant pathogen that causes wilt disease and significant agricultural losses. As resistance to chemical fungicides continues to rise, natural plant-derived antimicrobials, such as cannabidiol (CBD), have emerged as promising alternatives due to their reported antifungal properties (Cárdenas-Laverde et al., 2021). The purpose of this study was to evaluate whether two commercially available CBD tinctures (50 mg/mL and 300 mg/mL) could inhibit the growth of F. oxysporum. It was hypothesized that CBD would inhibit fungal growth in a concentration-dependent manner, with the 300 mg/mL tincture producing the largest zone of inhibition (ZOI). Using an agar diffusion assay, sterile PDA (potato dextrose agar) plates were inoculated with F. oxysporum and treated with disks soaked in lab-grade water, 50 mg/mL CBD, or 300 mg/mL CBD. Plates were incubated, and ZOIs were measured over four days. The 50 mg/mL CBD treatment produced some antifungal activity across all four days, while the 300 mg/mL CBD tincture showed little antifungal activity on the first day and none afterwards. A one-way ANOVA revealed significant differences among treatment groups (Day 1: F(2, 87) =5.88, p=0.004) driven almost entirely by the inhibitory activity in the 50 mg/mL plates. Tukey post-hoc tests showed that the 50 mg/mL group differed from the others, while the 300 mg/mL tincture barely differed from the sterile control. These findings indicate that CBD can inhibit F. oxysporum, but higher concentrations or flavored tinctures may lose antifungal activity, likely due to added carrier ingredients or the nature of the concentration. CBD, therefore, shows potential as a natural antifungal agent, but formulation plays a critical role in determining its effectiveness.