In a similar study, it was found that orange juice, which is high in potassium, was able to have a positive effect on the cell growth of algae (Dalgish et al. We understand that algae need carbon dioxide and sunlight to grow and it thrives in environments high in nitrogen, phosphorus, and potassium. These studies provide information about possible new ways to protect apple juice and possibly other foods against infection by human pathogens.For our study we wanted to find an efficient and safe way to increase the expected growth rate of Chlorella vulgaris (Algae) by measuring its turbidity and pH levels. Analysis of the oils by HPLC showed that the bactericidal results are related to the composition of the oils. Studies with citrate and maleate buffers of the same pH as apple juice suggest that the acidity of the juice contributes to the bactericidal activity. Lemon oil induced the highest enhancement, 6.9-fold for E. The enhanced activity in apple juice compared to the pH 7 buffer was greater for S. coli ranged from 0.023 to 0.14 and for S. In apple juice at 60 min, BA50 values for E. The test compounds were more active in apple juice than in the buffer. Dose-response plots were used to determine the % of the sample that resulted in a 50% decrease in the colony forming units as compared to a control sample (BA50). enterica) at ~5 min and 21 oC and after incubation for 60 min at 37 oC. Technical Abstract: We evaluated several plant essential oils (cinnamon bark, cinnamon Cassia, cinnamon leaf, clove bud, lemon, lemon grass, orange bitter, orange Mandarin, oregano Spanish, palmarosa, rose Geranium, and thyme) and their major components (carvacrol, cinnamaldehyde, citral, eugenol, geraniol, limonene, and perillaldehyde) for anti-microbial activity in a pH 7 PBS buffer and in apple juice (pH 3.7) against Escherichia coli O157:H7 (E. These studies provide information about possible new ways to protect apple juice and possibly other foods against infection by human pathogens. Analysis of the essential oils by an HPLC method we developed showed that the antimicrobial activities of the oils are directly related to their content of the active bactericidal components. The enhancement of activity in apple juice was greater for Salmonella than for E. The results show that the 19 selected test compounds evaluated were more active in pH 3.7 apple juice than in a pH 7 buffer. coli O157:H7 and Salmonella enterica added to a prototype food, apple juice. Based on the previous observations, we then evaluated the antimicrobial activities of some of the more active samples against E. Interpretive Summary: To assess the anitmicrobial potential of natural compounds and plant extracts, we previously evaluated the relative bactericidal activities of about 119 plant essential oils and their active components against four human pathogens, Campylobacter jejuni, E.coli O157:H7,Listeria monocytogenes, and Salmonella enterica (Journal of Food Protection, accepted for publication). Journal of Agriculture and Food Chemistry. Bacterial activities of plant essential oils and their components against escherichia coli O157:H7 and salmonella enterica in apple juice. Submitted to: Journal of Agriculture and Food ChemistryĬitation: Friedman, M., Henika, P.R., Levin, C.E., Mandrell, R.E.
0 Comments
Leave a Reply. |