Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leaves
Abstract Bacteriophage and gaseous ozone are evolving as meritorious alternatives to conventional sanitizers in food postharvest applications. Here, we investigated the efficacy of sequential treatments of a lytic bacteriophage and gaseous ozone, during vacuum cooling of fresh produce, against Esche...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2023-07-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-023-36815-9 |
| _version_ | 1797784669326934016 |
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| author | Mustafa Yesil David R. Kasler En Huang Ahmed E. Yousef |
| author_facet | Mustafa Yesil David R. Kasler En Huang Ahmed E. Yousef |
| author_sort | Mustafa Yesil |
| collection | DOAJ |
| description | Abstract Bacteriophage and gaseous ozone are evolving as meritorious alternatives to conventional sanitizers in food postharvest applications. Here, we investigated the efficacy of sequential treatments of a lytic bacteriophage and gaseous ozone, during vacuum cooling of fresh produce, against Escherichia coli O157:H7. Spinach leaves were spot-inoculated with 105–107 CFU g−1 E. coli O157:H7 B6-914 and treated with Escherichia phage OSYSP spray (109 PFU g−1), gaseous ozone, or their combination. Vacuum cooling, which preceded or followed phage application but ran concomitantly with ozone treatment, was performed in a custom-made vessel at the following process sequence: vacuum to 28.5 in. Hg, vessel pressurization to 10 psig with gas containing 1.5 g ozone/kg gas-mix, holding for 30 min, and vessel depressurization to ambient pressure. Bacteriophage or gaseous ozone inactivated E. coli O157:H7, applied at different initial populations on spinach leaves, by 1.7–2.0 or 1.8–3.5 log CFU g−1, respectively. At the high inoculum levels tested (7.1 log CFU g−1), sequential treatments of phage and ozone reduced E. coli O157:H7 population by 4.0 log CFU g−1, but when treatment order was reversed (i.e., ozone followed by bacteriophage), the combination synergistically decreased pathogen’s population on spinach leaves by 5.2 log CFU g−1. Regardless the antibacterial application order, E. coli O157:H7 populations, applied initially at ~ 105 CFU g−1, were reduced below the enumeration method’s detection level (i.e., < 101 CFU g−1). The study proved that bacteriophage–ozone combination, applied in conjunction with vacuum cooling, is a potent pathogen intervention strategy in fresh produce post-harvest applications. |
| first_indexed | 2024-03-13T00:43:11Z |
| format | Article |
| id | doaj.art-070cfdb1cdf44a2cb4c74373c1d916e3 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-03-13T00:43:11Z |
| publishDate | 2023-07-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-070cfdb1cdf44a2cb4c74373c1d916e32023-07-09T11:11:47ZengNature PortfolioScientific Reports2045-23222023-07-0113111210.1038/s41598-023-36815-9Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leavesMustafa Yesil0David R. Kasler1En Huang2Ahmed E. Yousef3Department of Food Science and Technology, The Ohio State UniversityDepartment of Food Science and Technology, The Ohio State UniversityDepartment of Food Science and Technology, The Ohio State UniversityDepartment of Food Science and Technology, The Ohio State UniversityAbstract Bacteriophage and gaseous ozone are evolving as meritorious alternatives to conventional sanitizers in food postharvest applications. Here, we investigated the efficacy of sequential treatments of a lytic bacteriophage and gaseous ozone, during vacuum cooling of fresh produce, against Escherichia coli O157:H7. Spinach leaves were spot-inoculated with 105–107 CFU g−1 E. coli O157:H7 B6-914 and treated with Escherichia phage OSYSP spray (109 PFU g−1), gaseous ozone, or their combination. Vacuum cooling, which preceded or followed phage application but ran concomitantly with ozone treatment, was performed in a custom-made vessel at the following process sequence: vacuum to 28.5 in. Hg, vessel pressurization to 10 psig with gas containing 1.5 g ozone/kg gas-mix, holding for 30 min, and vessel depressurization to ambient pressure. Bacteriophage or gaseous ozone inactivated E. coli O157:H7, applied at different initial populations on spinach leaves, by 1.7–2.0 or 1.8–3.5 log CFU g−1, respectively. At the high inoculum levels tested (7.1 log CFU g−1), sequential treatments of phage and ozone reduced E. coli O157:H7 population by 4.0 log CFU g−1, but when treatment order was reversed (i.e., ozone followed by bacteriophage), the combination synergistically decreased pathogen’s population on spinach leaves by 5.2 log CFU g−1. Regardless the antibacterial application order, E. coli O157:H7 populations, applied initially at ~ 105 CFU g−1, were reduced below the enumeration method’s detection level (i.e., < 101 CFU g−1). The study proved that bacteriophage–ozone combination, applied in conjunction with vacuum cooling, is a potent pathogen intervention strategy in fresh produce post-harvest applications.https://doi.org/10.1038/s41598-023-36815-9 |
| spellingShingle | Mustafa Yesil David R. Kasler En Huang Ahmed E. Yousef Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leaves Scientific Reports |
| title | Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leaves |
| title_full | Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leaves |
| title_fullStr | Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leaves |
| title_full_unstemmed | Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leaves |
| title_short | Lytic Escherichia phage OSYSP acts additively and synergistically with gaseous ozone against Escherichia coli O157:H7 on spinach leaves |
| title_sort | lytic escherichia phage osysp acts additively and synergistically with gaseous ozone against escherichia coli o157 h7 on spinach leaves |
| url | https://doi.org/10.1038/s41598-023-36815-9 |
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