ST_437_presentation

Yoko clack

Background

  • About 1/3 of fresh produce is wasted
    • Spoilage fungi are a major contributor to post-harvest loss
  • Synthetic fungicides have limitations
    • Emergence of multidrug-resistant fungi
    • Consumer safety concerns and preference for clean-label products

Background

  • Grape Pomace Extract (GPE)
    • Low-cost, natural source of plant phenolics
    • Derived from winery waste (circular economy valorization)
    • Phenolics exhibit antioxidant and pro-oxidant activity
    • Phenolics absorb UV-A light
      • Undergo photoactivation upon exposure
      • Enhances antimicrobial activity

Growth Curve Basics

Gompertz modeling Fitting

Model

\[ \text{OD}_{595}(t) = a + (b - a)\,\exp\left(-\exp\left(-c(t - d)\right)\right) \] - \((a)\): Upper asymptote

  • \((b)\): Lower asymptote

  • \((G_{\text{R}})\): Maximum growth rate

  • \((T_{\text{IP}})\): Time of Inflection Point / Time of \((G_{\text{R}})\)

Good Model Fit

Good Model Fit

Good Model Fit

Good Model Fit

Good Model Fit

Good Model Fit

Good Model Fit

Good Model Fit

Δ Lag Phase duration (LPD)

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

##{.center} \[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD = T_{\text{IP 1}} - T_{\text{IP 2}} \]

\[ ΔLPD \approx 11.9 \ \text{ hours} \approx 1 \text{ log reduction} \]

Relationship Between ΔLPD & Viable Cell Reduction