Response of Aspergillus niger Inoculated on Tomatoes Exposed to Vapor Phase Mustard Essential Oil for Short or Long Periods and Sensory Evaluation of Treated Tomatoes

Abstract

The inhibitory effect of mustard essential oil (EO) in vapor phase against Aspergillus niger was evaluated in vitro and in vivo (in tomatoes). Mold response in tomatoes exposed for short or long periods to selected concentrations of mustard EO was also evaluated. Furthermore, a sensory evaluation was also performed among treated tomatoes and compared with nontreated ones. Minimum inhibitory concentration (MIC) for the studied EO was determined by the inverted Petri dish method. MIC for the in vitro and in vivo tests for mustard EO was of 3.08 L/L air . In vitro and in vivo results demonstrate the effectiveness of vapors of mustard EO against A. niger. The studied EO contains highly volatile organic compounds with strong inhibitory effects, even when applied for short periods, and can consequently be considered a good alternative to traditional synthetic antimicrobials without detriment of selected sensory attributes.

In Vitro and In Vivo Antifungal Activity of Clove (Eugenia caryophyllata) and Pepper (Piper nigrum L.) Essential Oils and Functional Extracts Against Fusarium oxysporum and Aspergillus niger in Tomato (Solanum lycopersicum L.)

“…erefore, we can confirm that the essential oils and functional extracts evaluated in vivo against the species A. niger and F. oxysporum in the tomato fruit did not show strong inhibition; however, total inhibition could be demonstrated in the in vitro tests; this can be attributed to the existence of some factors that may affect the antifungal efficiency, such as the food components, inactivation due to the addition of other component, effects of pH over antifungal stability and activity, unequal distribution in the food matrix, and low solubility of extracts [36]. Additionally, Aguilar-Gonzalez et al [37] demonstrated in vitro the effectiveness of mustard EO vapor against A. niger in tomatoes and concluded that mustard EO contains highly volatile compounds with strong inhibitory effects. However, these results were obtained with essential oils used in the vapor phase.…”

Volatile Antimicrobial Agents and In Vitro Methods for Evaluating Their Activity in the Vapour Phase: A Review

“…Aspergillus flavus O 100 % 0.33 µL/mL [81] Aspergillus niger O 100 % 0.33 µL/mL [81] Aspergillus ochraceus O 100 % 0.33 µL/mL [81] Continued ▶ Aspergillus fumigatus MIC 0.025 µg/mL [92] Aspergillus niger MIC 0.020 µg/mL; 3.08 µL/L air [91,93] Aspergillus nomius MIC 0.060 µg/mL [92] Bacillus subtilis MIC 0.250 µg/mL [92] Candida albicans MIC 0.012 µg/mL [92] Cryptococcus neoformans MIC 0.060 µg/mL [92] Escherichia. coli MIC 0.050 µg/mL [92] Eupenicillum hirayamae MIC 0.060 µg/mL [92] Mycobacterium smegmatis MIC 0.012 µg/mL [92] Penicillium cinnamopurpureum MIC 0.025 µg/mL [92] Penicillium expansum MIC 0.012 µg/mL [92] Penicillium viridicatum MIC 0.060 µg/mL [92] Pseudomonas aeruginosa MIC 0.012 µg/mL [92] Salmonella typhimurium MIC 0.025 µg/mL; IZ 57.5-85.0 mm for 10 µL of EO [91,94] Staphylococcus aureus MIC 0.012 µg/mL [92] Streptococcus pyogenes MIC 0.012 µg/mL [92] Trichophyton rubrum MIC 0.050 µg/mL [92] Continued ▶ Staphylococcus aureus MIC 64-1024 µg/mL [65,66] Streptococcus pneumoniae MIC 64 µg/mL [65] disc volatilization method…”