Progress 01/01/21 to 12/31/24
Outputs
Target Audience:1) Food Safety Professionals Efforts: a) Submitted and Presenteda technical abstract to the Annual Meeting of Food Technologists (IAFP), Annual Meeting of the Institute of Food Technologists (IFT) and Annual Meeting of American Chemical Society (ACS). b) Introduced the concept and results of the project with Professionals in the Food Industry and discussed the potential applications in food products, c) Published a paper in the scientific journalsto disseminate results to professionals. 2) Food Packaging Professionals Efforts: a) Introduced the novel packaging solutions to the professionals from packaging companies, b) present the outcomes of the research in professional conferences. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?In the Department of Food Science and Technology at Virginia Tech, a graduate student is being trained to design and manufacture dye-TiO2 conjugates, analytical skills for determining ROS, and lab skills to culture bacteria. The student is also being trained to present outcomes to the public and write scientific journal articles. In the Department of Sustainable Biomaterials at Virginia Tech, a graduate student has been trained to make and evaluate nanocellulose biodegradable packaging films and write scientific journal articles. In the Department of Civil and Environmental Engineering at the George Washington University, a graduate student has been trained to synthesize and characterize photocatalytic materials. How have the results been disseminated to communities of interest?The results have been disseminated to the public through presenting posters in professional meetings (e.g., IFT Annual Meetings, IAFP Annual Meeting, and Virginia Tech Research Symposiums), publishing research articles in peer-reviewed journals, and discussing outcomes with professionals from the food industry. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Microbes that contaminate food can cause it to spoil and may lead to serious illnesses. Packaging plays a key role in keeping food safe during storage, handling, and transport, and it also helps extend how long food stays fresh. One promising idea is to add germ-fighting substances into packaging materials to help prevent spoilage and protect against harmful bacteria. However, many current solutions don't last long, may be unsafe for people, or don't work against a wide range of bacteria. This project developed a new kind of food packaging film that uses light to power a safe, chemical-free way to kill many types of bacteria. When exposed to regular light, this special film produces natural compounds that break down bacteria on food and packaging surfaces. This eco-friendly, residue-free technology could be a powerful tool to improve food safety and reduce waste. Objective 1. Create a photocatalytic dye-TiO2 conjugate system for efficient ROS generation under visible light. Five dyes and their relative dye-TiO2 conjugates were selected to test the antibacterial properties of E. coli under visible light (6000 lux; 3.13 mW/cm2). Among them, Tetra(4-carboxyphenyl) porphyrin (TcPP) demonstrated promising antibacterial performance under visible light, showing a 2.9-log reduction in E. coli compared with its dark counterpart. Analytical results showed that the conjugates of TiO2 and TcPP produced high amounts of singlet oxygen and hydrogen peroxide as reactive oxygen species (ROS). We then developed a visible light-responsive antimicrobial packaging film that incorporates photocatalytic conjugates of TiO2 and TcPP. The conjugates incorporated cellulose films harvest visible light energy and excite electrons on TcPP to transfer to the surface of TiO2, generating reactive oxygen species (ROS) to inactivate contaminated bacteria on films or food. The film's antimicrobial properties were evaluated under different light intensities and against different bacteria suspended in phosphate-buffered saline. Under a high light intensity of 6000 lux, the conjugates incorporated film resulted in a 4.5, 4.6, 4.1, and 4.7 log CFU/mL reduction in Escherichia coli, Pseudomonas fluorescens, Leuconostoc lactis and Listeria innocua, respectively, within 72 hours. Under a low light intensity of 1000 lux, the film led to a 2.5, 1.8, 2.0, and 4.2 log CFU/mL reduction in E. coli, P. fluorescens, Leu lactis, and Lis innocua, respectively, within 96 hours. Objective 2. Design, fabricate, and characterize the physical, mechanical, antimicrobial properties of the dye-TiO2 incorporated biopolymer film? Development of antimicrobial active packaging systems incorporating dye-TiO2 conjugates produced from Objective 1 has been successfully conducted. Three different types of biopolymeric packaging materials have been screened. Those include nanocellulose, paper, and polylactic acid (PLA). Among these biopolymers, single layer films made from nanocellulose showed the highest antimicrobial activity due to high light transparency and possibility of diffusion of ROS within polymeric matrix. A series of nanocellulose films containing TcPP-TiO2 conjugates were produced as a function of the number of homogenization process of nano-cellulose film forming solution. Five times homogenization process showed the highest distribution of dye-TiO2 into the polymeric matrix and highest mechanical strength due to the large number of fibrillations of cellulose. It was confirmed by SEM evaluation and other mechanical tests. Multilayer film structures composed of paper and nanocellulose were also developed by a casting method. TcPP-TiO2 conjugates were included into the nanocellulose layer which was designed for contacting layer for antimicrobial activity. We found it shows a similar antimicrobial activity compared to the single layer film made from nanocellulose alone. Objective 3. Determine the film's effectiveness in inactivating bacteria and preserving food quality in a food matrix. We determined the TcPP-TiO2 incorporated film's antimicrobial effectiveness on different food matrices, including cucumber, cherry tomato, mango, and chicken breast. The TcPP-TiO2 film was able to decrease the number of E. coli on cucumber by 3.2 logs after 24 hours of visible light exposure of 6,000 lux. After 48 hr of the light exposure, the E. coli number was further decreased to 1.0 log CFU/mL, indicating that the strong antimicrobial properties of the film can be applied to real food products. We further determined the TcPP-TiO2 incorporated film's antimicrobial effectiveness on cherry tomatoes, which were inoculated with ~7.0 log CFU/mL of E. coli. The results showed that the E. coli number on cherry tomatoes decreased to 5.9 log CFU/mL after 4 days of visible light exposure of 1,500 lux and to 5.9 log CFU/mL after 4 days of visible light exposure of 3,000 lux. On other hand, the control samples maintained the E. coli number of 6.9-7.0 log CFU/mL on cherry tomatoes. The conjugate films also resulted in a 3.0 log reduction in Salmonella enterica on mango surfaces after 24 hours of exposure to 6000-lux light irradiation. A similar result was observed when the sample was exposed to 3000-lux light. When the light intensity was reduced to 1000 lux, there was a significant difference (2.7 log) in S. enterica count between the control film treatment and conjugate film treatment at 24 hours. However, inactivation of the S. enterica inoculated on chicken breast covered by the film were minimal, indicating the limitations of the film on meat products. In addition, we did not found any potential food quality deterioration due to the potential oxidation effect by ROS.
Publications
- Type:
Peer Reviewed Journal Articles
Status:
Published
Year Published:
2024
Citation:
Xu, Z., Wu, J., Lovely, B., Li, Y., Ponder, M., Waterman, K., Kim, Y.T., Shuai, D., Yin, Y. and Huang, H. (2024) Visible light-activated dye-sensitized TiO2 antibacterial film: A novel strategy for enhancing food safety and quality. Journal of Hazardous Materials, 480, p.136296.
- Type:
Peer Reviewed Journal Articles
Status:
Published
Year Published:
2025
Citation:
Lovely, B., Kim, Y.T.*, Huang, H., Zink-Sharp, A. and Roman, M. (2025) Impacts of cycles of a novel low-pressure homogenization process on cellulose nanofibrils (CNF) as a sustainable packaging film material. Carbohydrate Polymer Technologies and Applications, 9, p.100739.
- Type:
Peer Reviewed Journal Articles
Status:
Submitted
Year Published:
2025
Citation:
Xu, Z., He, Z., Li, Y., Shen, H., Kim, Y.-T., Shuai, D., Yin, Y., Huang, H.*, Ponder, M.* (2025) Visible Light Responsive Packaging Films Effect for the Inactivation of Multi-drug Resistant Salmonella enterica. (Submitted)
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Xu Z., Wu J., Lovely B., Ham W., Li Y., Ponder M., Waterman K., Kim Y-T., Shuai D., Yin Y., Huang H.* (2024) Development of Visible-light Responsive Antimicrobial Packaging Film with Dye-Sensitized TiO2 Conjugates to Enhance Food Safety. International Association for Food Protection (IAFP) Annual Meeting. Long Beach, CA. July, 2024.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2025
Citation:
Xu, Z., Li, Y., He, Z., Shen, H., Kim, Y.-T., Shuai, D., Yin, Y., Huang, H.*, Ponder, M.* (2025) Rapid reductions of drug-resistant bacteria on foods and contact surfaces using novel photocatalytic films. Virginia Tech Food Science Symposium, Blacksburg, VA. April, 2025.
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2025
Citation:
Xu, Z., He, Z., Li, Y., Shen, H., Kim, Y.-T., Shuai, D., Yin, Y., Huang, H.*, Ponder, M.* (2025) Inactivation of Multidrug-Resistant Salmonella enterica in Foods Using TiO2-TcPP Incorporated Cellulose Nanofibril-Based Photocatalytic Packaging. International Association for Food Protection (IAFP) Annual Meeting. Cleveland, OH, July, 2025.
- Type:
Conference Papers and Presentations
Status:
Submitted
Year Published:
2025
Citation:
Xu, Z., He, Z., Li, Y., Shen, H., Kim, Y.-T., Shuai, D., Yin, Y., Huang, H.*, Ponder, M.* (2025) Shedding Light on Superbugs: A Cellulose-Based Photocatalytic Surface to Inactivate Methicillin-Resistant Staphylococcus aureus. American Chemical Society (ACS) Annual Meeting, Washington D.C., D.C., August, 2025.
- Type:
Peer Reviewed Journal Articles
Status:
Submitted
Year Published:
2025
Citation:
Lovely, B., Xu, Z., Kim, Y.-T.*, Huang, H., Hong, S. J. (2025) TiO2-TCPP Functionalized CNF as a High-Barrier, UV-Blocking, and Visible Light-Responsive Antimicrobial Packaging Material.(submitted)
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2024
Citation:
Xu, Z., Wu, J., Lovely, B., Li, Y., Ponder, M., Waterman, K., Kim, Y., Shuai, D., Yin, Y., Huang, H.* (2024) Visible Light-Responsive Antibacterial Packaging Films for Improving Food Quality and Safety. CeZAP (Center for Emerging, Zoonotic,
and Arthropod-borne Pathogens) Infectious Diseases Research Symposium, Blacksburg, VA, October, 2024.
|
Progress 01/01/23 to 12/31/23
Outputs
Target Audience:1) FoodSafety Professionals. Efforts: a) Submitted a technical abstract to the 2024Annual Meeting of Food Technologists (IAFP) and will present the poster in July 2024. b) Introduced the concept and results of the project with Professionals in the Food Industry and discussed the potential applications in food products, c) Published a paper in the ACS Food Science and Technology to disseminate results. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?In the Department of Food Science and Technology at Virginia Tech, a graduate studentis being trained to design and manufacture dye-TiO2 conjugates, analytical skills for determining ROS, and lab skills to culture bacteria. The student is also being trained to present outcomes to the public and write write scientific journal articles. In the Department of Sustainable Biomaterials at Virginia Tech, a graduate student is being trained to make and evaluate nanocellulose biodegradable packaging films and write scientific journal articles. How have the results been disseminated to communities of interest?The results have been disseminated to the public through presenting posters in professional meetings (2023 IFT Annual Meetings, and Virginia Tech Research Symposiums), publishing research articles in peer-reviewed journals,and discussing outcomes with professionals from the food industry. What do you plan to do during the next reporting period to accomplish the goals?1) Evaluate the antimicrobial efficacy of the packaging film against antibiotic resistant microorganisms. 2) Design and fabricate multi-layer films that incorporate the TcPP-TiO2 conjugates and evaluate their antimicrobial properties. 3) Thoroughly characterize and quantify the types of reactive oxygen species (ROS) generated by the TcPP-TiO2 conjugate incorporated films.
Impacts
What was accomplished under these goals?
Microbial contamination causes food spoilage and increases the risk of foodborne illnesses. Food packaging materials are crucial for safe food storage, handling, and transportation, and play an essential role in extending the shelf-life of foods. Antimicrobial embedded packaging materials, a type of smart packaging, hold promise for reducing food spoilage and preventing foodborne diseases; however, current antimicrobial packaging solutions face challenges, including rapid exhaustion of antimicrobial agents, potential toxicity by some of the antimicrobial agents, and the inability to inactivate a broad spectrum of bacteria. the overall goal of this proposal is to develop a photo-responsive, antimicrobial packaging film using dye-sensitized TiO2 bio-composites to improve food quality and safety. Objective 1. Create a photocatalytic dye-TiO2 conjugate system for efficient ROS generation under visible light. We developed a visible light-responsive antimicrobial packaging film that incorporates photocatalytic conjugates of TiO2 and Tetra(4-carboxyphenyl) porphyrin (TcPP). The conjugates incorporated cellulose films harvest visible light energy and excite electrons on TcPP to transfer to the surface of TiO2, generating reactive oxygen species (ROS) to inactivate contaminated bacteria on films or food. The film's antimicrobial properties were evaluated under different light intensities and against different bacteria suspended in phosphate-buffered saline. Under a high light intensity of 6000 lux, the conjugates incorporated film resulted in a 4.5, 4.6, 4.1, and 4.7 log CFU/mL reduction in Escherichia coli, Pseudomonas fluorescens, Leuconostoc lactis and Listeria innocua, respectively, within 72 hours. Under a low light intensity of 1000 lux, the film led to a 2.5, 1.8, 2.0, and 4.2 log CFU/mL reduction in E. coli, P. fluorescens, Leu lactis, and Lis innocua, respectively, within 96 hours. Objective 2. Design, fabricate, and characterize the physical, mechanical, antimicrobialproperties of the dye-TiO2 incorporated biopolymer film Development of antimicrobial active packaging systems incorporating dye-TiO2 conjugates produced from Objective 1 has been successfully conducted. Three different types of biopolymeric packaging materials have been screened. Those include nanocellulose, paper, and polylactic acid (PLA). Among these biopolymers, single layer films made from nanocellulose showed the highest antimicrobial activity due to high light transparency and possibility of diffusion of ROS within polymeric matrix. PLA films containing dye-TiO2 were prepared by organic solvent casting methods, but it didn't show antimicrobial activities. It was attributed by the phase separation of dye-TiO2 conjugates at organic solvent system. A series of nano-cellulose films containing dye-TiO2 conjugates were produced as a function of the number of homogenization process of nano-cellulose film forming solution. Five times homogenization process showed the highest distribution of dye-TiO2 into the polymeric matrix and highest mechanical strength due to the large number of fibrillations of cellulose. It was confirmed by SEM evaluation and other mechanical tests. Multilayer film structures composed of paper and nanocellulose were also developed by a casting method. dye-TiO2 conjugates were included into the nanocellulose layer which was designed for contacting layer for antimicrobial activity. We found it shows a similar antimicrobial activity compared to the single layer film made from nanocellulose alone. Objective 3. Determine the film's effectiveness in inactivating bacteria and preserving food quality in a food matrix. We determined the TcPP-TiO2 incorporated film's antimicrobial effectiveness on cucumber, which was inoculated with 4.5 log CFU/mL of E. coli. The TcPP-TiO2 film was able to decrease the number of E. coli on cucumber by 3.2 logs after 24 hours of visible light exposure of 6,000 lux. After 48 hr of the light exposure, the E. coli number was further decreased to 1.0 log CFU/mL, indicating that the strong antimicrobial properties of the film can be applied to real food products. We further determined the TcPP-TiO2 incorporated film's antimicrobial effectiveness on cherry tomatoes, which were inoculated with ~7.0 log CFU/mL of E. coli. The results showed that the E. coli number on cherry tomatoes decreased to 5.9 log CFU/mL after 4 days of visible light exposure of 1,500 lux and to 5.9 log CFU/mL after 4 days of visible light exposure of 3,000 lux. On other hand, the control samples maintained the E. coli number of 6.9-7.0 log CFU/mL on cherry tomatoes.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2023
Citation:
Xu Z., Wu J., Lovely B., Ponder M., Waterman K., Kim Y-T., Shuai D., Yin Y., Huang H.* Development of a visible light-responsive antimicrobial packaging film for improving food safety. Macromolecules Innovation Institute Technical Conference, Blacksburg, VA. October, 2024.
- Type:
Journal Articles
Status:
Published
Year Published:
2024
Citation:
Johnson, A., Wu, J., Zhou, Z., Li, Y., Yin, Y., Ponder, M.A., Kim, Y.T., Shuai, D. and Huang, H.* (2024). Efficacy of a Rose Bengal-Embedded Antimicrobial Packaging Film in Inactivating Escherichia coli under Visible Light Irradiation. ACS Food Science & Technology (online available).https://doi.org/10.1021/acsfoodscitech.4c00040
- Type:
Journal Articles
Status:
Submitted
Year Published:
2024
Citation:
Xu Z.#, Wu J.#, Lovely B., Ham W., Li Y., Ponder M., Waterman K., Kim Y-T., Shuai D., Yin Y., Huang H.* (2024) Visible Light-Responsive Antimicrobial Packaging Films for Improving Food Quality and Safety.
- Type:
Conference Papers and Presentations
Status:
Submitted
Year Published:
2024
Citation:
Xu Z., Wu J., Lovely B., Ham W., Li Y., Ponder M., Waterman K., Kim Y-T., Shuai D., Yin Y., Huang H.* (2024) Development of Visible-light Responsive Antimicrobial Packaging Film with Dye-Sensitized TiO2 Conjugates to Enhance Food Safety. International Association for Food Protection (IAFP) Annual Meeting. Long Beach, CA. July, 2024.
|
Progress 01/01/22 to 12/31/22
Outputs
Target Audience:Target Audience: 1) Food Packaging Companies. Efforts: 1) Submitted a technical abstract to the 2022 Annual Meeting of Food Technologists (IFT) and will present the poster in July 2023. 2) Introduced the concept and results of the project with Professionals in the Food Industry and discussed the potential applications in food products Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?In the Department of Food Science and Technology at Virginia Tech, a graduate student and a research associate is being trained to design and manufacture dye-TiO2 conjugates, analytical skills for determining ROS, and lab skills to culture bacteria. In the Department of Sustainable Biomaterials at Virginia Tech, a graduate student is being trained to make and evaluate nanocellulose biodegradable packaging films. In the Department of Civil and Environmental Engineering at George Washington University, a graduate student is being trained to characterize the dye-TiO2 conjugates and incorporate the conjugates into packaging films by electrospinning. How have the results been disseminated to communities of interest?The results will be disseminated to the public through presenting posters in professional meetings (2022 and 2023 IFT Annual Meetings and Virginia Tech Research Symposiums) and discussing outcomes with professionals from the food industry. What do you plan to do during the next reporting period to accomplish the goals?1) Evaluate the antimicrobial efficacy of the packaging film under different light intensities and time durations 2) Evaluate the effectiveness of the packaging film against microorganisms in different food systems 3) Design and fabricate multi-layer films to reduce the conjugate leaching from the films.
Impacts
What was accomplished under these goals?
Microbial contamination causes food spoilage and increases the risk of foodborne illnesses. Food packaging materials are crucial for safe food storage, handling, and transportation, and play an essential role in extending the shelf-life of foods. Antimicrobial embedded packaging materials, a type of smart packaging, hold promise for reducing food spoilage and preventing foodborne diseases; however, current antimicrobial packaging solutions face challenges, including rapid exhaustion of antimicrobial agents, potential toxicity by some of the antimicrobial agents, and the inability to inactivate a broad spectrum of bacteria. the overall goal of this proposal is to develop a photo-responsive, antimicrobial packaging film using dye-sensitized TiO2 bio-composites to improve food quality and safety. We have synthesized TiO2-TcPP (dye) conjugates that can harvest visible light to generate reactive oxygen species (ROS) for effectively inhibiting microorganisms. The inhibitory effect of TiO2-TcPP conjugates was firstly analyzed by adding conjugate suspensions in vitro E. coli culture and verified by the change of E. coli population compared with controls. Multiple levels of suspended conjugate were added to the E. coli culture, and TiO2 suspension (zero TcPP), TcPP solution (no TiO2), and sterile water only were all tested as controls. The results showed that the controls (TiO2 suspension, sterile water) did not lead to any inhibition to E. coli, and the TcPP solution caused about 2 log reduction in E. coli under 24 hr of visible light irradiation. Most promisingly, the TiO2-TcPP conjugates suspension shows about 4 log reduction under the same condition. We further employed several assays to analyze the generation of ROS during the light-sensitization of TiO2-TcPP. The results showed that the generations of singlet oxygen and H2O2 are the main reason for the strong bacterial inhibitory activity of TCPP. We then incorporated TiO2-TcPP conjugates into cellulose nanofiber packaging film at a concentration of 0 to 2.0 mg/cm2 and tested the bacteriostatic effect of the conjugate-containing CNF films by immersing them into bacterial suspensions. The results showed that the conjugate-containing films have a strong antimicrobial capability, and the antimicrobial effect depends on the concentration of conjugate in films. When the conjugate concentration in the film is 2.0 mg/cm2, the film can cause a 1.5-log reduction in the E. coli population under visible light for 24 hr. We further test the inhibitory effect of the film against other types of bacteria, namely Listeria innocua, Pseudomonas fluorescens, and Leuconostoc mesenteroides. The results showed that the conjugates-containing film can effectively inhibit these bacteria and caused a 2-4 log reduction in the bacterial population under visible light within 48 hr. We have started to test the antimicrobial effect of the film on real food by using cucumber as a model food sample. Cucumber was aseptically cut into square cubes, inoculated with 3 logs of E. coli cells, and then covered by the film. The sample was then placed under visible light for 24 hours. The results showed that the cucumber covered by the conjugates-containing film had a 3-log reduction in bacterial cells, while the control (the film without the conjugates) only had a 0.3-log reduction in bacterial cells. Our results demonstrated that the conjugates-containing film can effectively inhibit the growth of the contaminated bacteria on food, and therefore, potentially extending food shelf life and reducing food loss caused by microbial contamination.
Publications
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2023
Citation:
Xu Z., Lovely B., Shuai, D., Wu. J., Ponder M., Kim, Y., Yin, Y., Huang, H. Development of a visible light-responsive antimicrobial packaging film for improving food safety. 2023 Annual Meeting of Institute of Food Technologists, Chicago, IL, July 2023
|
Progress 01/01/21 to 12/31/21
Outputs
Target Audience:Target Audience: 1) Food Packaging Companies. Efforts: 1) Submitted a technical abstract to the 2022 Annual Meeting of Food Technologists (IFT)and will present the posterin July 2022. 2) Introduced the concept andresults of the projectwith Professionals in the Food Industry and discussed the potential applications in food products Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?In the Department of Food Science and Technology at Virginia Tech, a graduate student and a research associateis being trained for designing and manufacturing dye-TiO2 conjugates, analytical skills for determining ROS, and lab skills to culture bacteria. In the Department of Sustainable Biomaterials, a graduate student is being trained to make and evaluate packaging films. In the Department of Civil and Environmental Engineering at George Washington University, a graduate student is being trained to characterize the dye-TiO2 conjugates and incorporate the conjugates into packaging films. How have the results been disseminated to communities of interest?The results will be disseminated to the public through presenting posters in professional meetings (2022 IFT Annual Meeting) and discussing outcomes with professionals from the food industry. What do you plan to do during the next reporting period to accomplish the goals?1) Evaluate the efficacy of the packaging film against other bacteria (e.g., Listeria) 2) Stabilize the dye-TiO2 conjugates in the packaging matrix and reduce the leaching of the conjugates 3) Design and fabricate multi-layer films with a PLA water-resistant protective layer 4) Determine the film's effectiveness in inactivating bacteria in a food matrix
Impacts
What was accomplished under these goals?
Microbial contamination causes food spoilage and increases the risk of foodborne illnesses. Food packaging materials are crucial for safe food storage, handling, and transportation, and play an essential role in extending the shelf-life of foods. The overall goal of this project is to develop a photo-responsive, antimicrobial packaging film using dye-sensitized TiO2 bio-composites to improve food quality and safety. The produced antimicrobial bio-composites will inactivate a wide range of spoilage and pathogenic bacteria attached to packaging materials or contained in food, thereby extending the shelf life of food, improving food safety, and reducing food loss during storage. 1. Objective 1: Create a photocatalytic dye-TiO2 conjugate system for efficient reactive oxygen species (ROS) generation under visible light. 1.1. Major activities completed / experiments conducted a) Developed methods to identify and quantify ROS generated by dyes and dye-TiO2 conjugates b) Screened dyes for high photocatalytic efficacy and antimicrobial capability under visible light c) Synthesized photocatalytic dye-TiO2 conjugates with high ROS generation and antimicrobial capacity under visible light 1.2. Data collected a) Among the popular photocatalytic dyes of rose bengal (RS), methylene blue, chlorophyllin, erythrosine, tartrazine, ruthenium compounds (N3), tetra (4-carboxyphenyl) porphyrin (TcPP) and its copper derivative (Cu-TcPP), RS and TcPP demonstrated high ROS generation and antimicrobial capacity in peptone solution under visible light. b) The TcPP-TiO2 conjugates successfully reduced the E. coli K12 cells in peptone solution by 3.5 logs under the irradiation of visible light for 18 hr. c) The analytical methods revealed that the singlet oxygen is the predominate ROS generated by the dye-TiO2 conjugates 1.3. Discussion of results The result demonstrated that TcPP-TiO2 conjugates have a high ROS generation efficacy and can effectively inactivate bacteria under visible light. The conjugates have the potential to be incorporated into packaging materials to inactive bacteria on the packaging surface. 1.4. Key outcomes Poster Presentation. Andrea Johnson, Jian Wu, Belladini Lovely, Zhe Zhou, Young-Teck Kim, Danmeng Shuai, Monica Ponder, Yun Yin, Haibo Huang. 2022 Annual Meeting of Institute of Food Technologists, Chicago, IL, July 2022 2. Objective 2: Design, fabricate, and characterize the physical, mechanical, and antimicrobial properties of the dye-TiO2 incorporated biopolymer film 2.1. Major activities completed / experiments conducted a) Designed and fabricated dye-TiO2 incorporated cellulose film b) Evaluated the antimicrobial capacity of the dye-TiO2 incorporated film 2.2. Data collected a) A TSA plate swab inoculated with 7 log CFU/mL E. coli. A circular film (5/8 inch, 15.88 mm) was placed on the inoculated agar and incubated under the same condition as the liquid test. The inhibitory zone was measured by a digital caliper. The results showed an inhibition halo thickness of 2.23 mm, indicating that the packaging film has the potential to inhibit bacteria growth. b) A circular cellulose film (5/8 inch, 15.88 mm) was placed in each well of a 24-well plate and 1 mL of ~5 log CFU/mL E. coli in peptone water was added to each of the wells. The results showed that 2.3 log reduction in E. coli cells under the irradiationof visible light (4500 K, ~7500 lux) for 24 hours. 2.3. Discussion of results The result demonstrated that TcPP-TiO2 incorporated packaging film has a strong antimicrobial activity against E. coli under visible light. The manufactured film has the potential to be used as a food packaging material to inactivate foodborne pathogens and extend food shelf life. 2.4. Key outcomes A manuscript is under preparation. 3. Objective 3: Determine the film's effectiveness in inactivating bacteria and preserving food quality in a real food matrix 3.1. Major activities completed / experiments conducted a) Evaluating the active film's efficacy to extend the shelf life of food 3.2. Data collected a) still collecting the data 3.3. Discussion of results N/A 3.4. Key outcomes N/A
Publications
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2022
Citation:
Andrea Johnson, Jian Wu, Belladini Lovely, Zhe Zhou, Young-Teck Kim, Danmeng Shuai, Monica Ponder, Yun Yin, Haibo Huang*. 2022 Annual Meeting of Institute of Food Technologists, Chicago, IL, July 2022
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