U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            MOORE, KATHERINE - University Of Arizonaitem
                                            Patel, Jituitem
                                            JARONI, DIVYA - Southern Universityitem
                                            Friedman, Mendelitem
                                            RAVISHANKAR, SADHANA - University Of Arizona
  Submitted to: Journal of Food Protection
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 7/12/2011
                                    Publication  Date: 10/1/2011
                                    Citation: Moore, K., Patel, J.R., Jaroni, D., Friedman, M., Ravishankar, S. 2011. Antimicrobial activity of apple, hibiscus, olive, and hydrogen peroxide formulations against Salmonella enterica on organic leafy greens. Journal of Food Protection. 74(10):1676-1683.Interpretive Summary: The effect of natural antimicrobials (plant extracts) in killing Salmonella on organic fresh produce was evaluated.  The leafy greens tested included organic romaine and iceberg lettuces and organic adult and baby spinach.  Produce leaves were inoculated with Salmonella Newport (6 log CFU/ml) and immerged in apple and olive extract formulations (1%, 3%, and 5%) or hibiscus formulations (10%, 20%, and 30%) for 2 min, and then stored at 4 °C.  Surviving populations of S. Newport in fresh produce were determined during storage at day 0, 1, and 3.  Olive extract exhibited the greatest antimicrobial activity, resulting in 2-3 log CFU/g reductions for each concentration and type of leafy green by day 3, followed by Apple extract and Hibiscus concentrate.  The maximum reduction by hydrogen peroxide (3%) was about 1 log CFU/g.  These natural antimicrobials also reduced background microflora of organic leafy greens up to 2.8 logs. This study demonstrates the potential of natural plant extract formulations to inactivate S. Newport on organic leafy greens.
                                Technical Abstract: Salmonella enterica is one of the most common bacterial pathogens involved in foodborne outbreaks with fresh produce in the last decade.  In an effort to discover safe antimicrobials for use on fresh produce, the objective of the present study was to evaluate the effectiveness of different antimicrobial plant extract/concentrate formulations on four types of organic leafy greens inoculated with S. enterica serovar Newport.  The leafy greens tested included organic romaine and iceberg lettuces and organic adult and baby spinach.  Each leaf sample was washed, dip inoculated with S. Newport (106 CFU/ml) and dried.  Apple and olive extract formulations were prepared at 1%, 3%, and 5% concentrations and hibiscus was prepared at 10%, 20%, and 30%.  Inoculated leaves were immersed in the treatment solution for 2 min, and individually incubated at 4 °C.  Following incubation, samples were taken at day 0, 1, and 3 for enumeration of survivors.  Our results showed that the antimicrobial activity was both concentration- and time-dependent.  Olive extract exhibited the greatest antimicrobial activity, resulting in 2-3 log CFU/g reductions for each concentration and type of leafy green by day 3.  Apple extract showed 1-2 log reductions by day 3 on various leafy greens.  Hibiscus concentrate showed an overall reduction of 1 log CFU/g for all leafy greens.  The maximum reduction by hydrogen peroxide (3%) was about 1 log CFU/g.  The antimicrobial activity was also tested on the background microflora of organic leafy greens and reductions ranged from 0-2.8 logs. This study demonstrates the potential of natural plant extract formulations to inactivate S. Newport on organic leafy greens.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov