Effect of Different pHs and Temperatures on Stability and Mode of Action of Musa paradisiaca L. Flower Extract against Foodborne Pathogens and Food Spoilage Microorganisms

Abstract

Raw foods contain harmful microorganisms that can infect processed foods and cause them to spoilage. To ensure safety and sustainability, processed foods are categorized depending on the required level of heat treatment and pH levels. This study aimed to assess the effect of different pHs and temperatures on the stability and mode of action of M. paradisiaca L. flower extract. The inhibition zone results after treating extracts with different pHs (3, 6, 7, and 11) for pathogenic bacteria and food spoilage ranged between 6.33 ± 0.47 to 16.67 ± 0.94 mm, and 6.00 ± 0.00 to 10.00 ± 0.00 mm, respectively. In terms of temperatures for foodborne pathogens (30, 50 and 80°C), E. coli showed the highest inhibition zone (11.67 ± 0.47 mm) at 30°C, while B. megaterium (12.00 ± 0.94 mm and 12.33 ± 0.47 mm) at 50 and 80°C. For the food fungi, C. krusei and C. parapsilosis showed the highest inhibition zone (8.33 ± 1.25 mm). The highest cell constituent release was at the concentration of 4×MIC for 4 and 96 h incubation and was found to be at 2.069%, 1.621%, 1.428%, and 1.643% for B. subtilis, E. coli, C.albicans and Asp. niger, respectively. The highest crystal violet uptake for B. subtilis, E. coli, C. albicans, and Asp. niger was 1.881, 2.082, 2.329, and 0.982 at 4׳ MIC after treatment for 4 and 96 h, respectively. In conclusion, M. paradisiaca L. flower extract exhibited antimicrobial activity, which showed stability after being subjected to different pHs and temperatures and can be developed as a natural sanitizing agent for washing raw foodstuffs.

Keywords

• musa paradisiaca
• antimicrobial activity
• flower extract
• cell constituents release
• crystal violet