The effect of Chinese Hibiscus on the survival of Staphylococcus aureus, Listeria monocytogenes and Escherichia coli in vitro and in food Industry

Abstract

Based on the results, Chinese Hibiscus extracts can act as inhibitors of bacteria in food product, when present at a sufficient concentration. The effect of Chinese Hibiscus on the survival of Staphylococcus aureus, Listeria monocytogenes and Escherichia coli in vitro and in food Industry Algimantas Slapkauskas1, Jurate Slapkauskaite2, Dalia Sekmokiene2 1Aleksandras Stulginskis University, Lithuania 2Lithuanian University of Health Sciences, Lithuania Foodborne disease is a global issue with significant impact on human health. With the growing consumer demand for natural preservatives to replace chemical compounds, plant antimicrobial compounds must be thoroughly investigated for their potential to serve as bio-preservatives. This study will focus on the plant-derived products such as Chinese Hibiscus as antimicrobial agents for use in food preservation and to control foodborne pathogens in foods. The objective of this study was to investigate the effectiveness of Chinese Hibiscus acetone, ethanol and water extracts against a number of common foodborne pathogens. The disc diffusion method was used to screen extracts against Listeria monocytogenes, Staphylococcus aureus and Escherichia coli. The survival of each species, demonstrated to be susceptible in vitro studies, was tested on curd type cheese and whey drink model system. The results indicate that inhibitory activity was dependent on the type and concentration of extract (p≤0.05). Chinese Hibiscus water extract was the most effective on L. monocytogene and S. aureus bacteria, although E. coli was inhibited by ethanol and acetone extracts. Gram-positive bacteria were more susceptible than Gram-negative bacteria in vitro. The effectiveness of these extracts was also tested in model food (cheese and whey) systems during storage. Chinese Hibiscus acetone extract (0.5%) in curd-type cheese was able to reduce E. coli significantly faster than the control (p≤0.05) during storage for 7 days. Than ethanol (0.5%) and water (1.0%) extract were able to reduce S. aureus and L. monocytogenes faster than the control sample, respectively.