Source: UNIV OF HAWAII submitted to
PREVENTION OF MICROBIAL ADHESION IN FOOD PROCESSING ENVIRONMENT USING MULTIFUNCTIONAL NANOPILLARED SURFACES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1005385
Grant No.
2015-67017-23083
Project No.
HAW02701-G
Proposal No.
2014-05756
Multistate No.
(N/A)
Program Code
A1331
Project Start Date
Jan 15, 2015
Project End Date
Jan 14, 2019
Grant Year
2015
Project Director
Jun, S.
Recipient Organization
UNIV OF HAWAII
3190 MAILE WAY
HONOLULU,HI 96822
Performing Department
HNFAS
Non Technical Summary
One of the major challenges in the fields of food science and biosafety of fresh and fresh-cut produce is to effectively prevent the formation of biofilms on the surfaces of food processing equipment and in facilities. It is known that nanoscale surface patterning and treatment techniques are capable of enabling precise control of molecular, physical, and biochemical interactions that govern bacterial adhesion to the solid substratum. This proposal is aimed to study and develop a novel multi-functional anti-microbial surface, i.e., robust and durable nanopillared surface with extrinsically low surface-free energy integrating with multifunctional elements such as superhydrophobicity and -slipperiness. We hypothesize that the nanoscale pillar patterns, smaller than bacterial dimensions (even their physical/biochemical/molecular sub-systems), integrated with controllable surface hydrophobicity and slipperiness, should be able to regulate the adhesion mechanics of bacteria, which would be unattainable with microscale surface or nanoscale porous patterns. This research aims to explore the adhesion mechanics of bacteria on multifunctional nanopillared surfaces and ultimately intends to develop an anti-bacterial surface that is environmentally acceptable, energy-efficient, and economically feasible in the area of food contact surfaces associated with fresh produce production and/or processing.
Animal Health Component
0%
Research Effort Categories
Basic
30%
Applied
30%
Developmental
40%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
71214302020100%
Knowledge Area
712 - Protect Food from Contamination by Pathogenic Microorganisms, Parasites, and Naturally Occurring Toxins;

Subject Of Investigation
1430 - Greens and leafy vegetables;

Field Of Science
2020 - Engineering;
Goals / Objectives
This research aims to explore the adhesion mechanics of bacteria on multifunctional nanopillared surfaces and ultimately intends to develop an anti-bacterial surface that is environmentally acceptable, energy-efficient, and economically feasible in the area of food contact surfaces associated with fresh produce production and/or processing. Specific objectives are to (1) study and develop a novel anti-microbial adhesion surface, i.e., robust and durable nanopillared surface with extrinsically low surface-free energy integrating with multifunctional elements such as super-hydrophobicity and -slipperiness and (2) test, simulate, and validate functions of the developed nano-engineered surface using a pilot-scale washing station designed for fresh produce processing.
Project Methods
Task 1. Study nanoscale patterning and treatment techniques for aluminum/stainless steel substrates and develop a prototype anti-microbial adhesion surface with controllable surface wettability and slipperiness. The PI group will use the developed protocols and recipes for processing different pore sizes and pillar heights during test trials. Based on the PI's input, Dr. Choi's research group will further optimize the wettability and slipperiness of the specimens controlled by precision spin coating with hydrophobic polymer i.e., Teflon and infusing the prepared surfaces with low-surface tension lubricant i.e., Krytox. Surface roughness measurement: Surface roughness characterization will be performed by the use of an atomic force microscopy (AFM) equipped with carbon nanotube tip (10-30 nm in diameter and < 1 µm in length, N-Tracer Scanning Probe Microscope, NanoFocus, Inc.).Scanning electron microscopy: Bare substrates will visualized using FESEM (Hitachi S-4800, 50,000X, Biological Electron Microscope Facility, UH). Substrates exposed to bacterial cells will be immersed in nitrogen slush for 10 s, freeze-dried using a Labconco FreeZone freeze dryer (Labconco Corp., Kansas City, MO) for 24 h, and then mounted onto stubs. Images obtained by SEM will be visually analyzed to determine the size and number of bacterial appendages that were visible on the attached cells.The number of appendages was categorized into the following groups: 0 to 5, 6 to 10, 11 to 15, 16 to 25, and >> 25. Cells categorized as >> 25 have too many appendages to count. The average roughness (Ra), root-mean-square roughness (Rrms), and 10-point height (Rz) will be extracted from the AFM images by using the free and open source software Gwyddion.Wear test: The wear and friction tests for evaluation of tribological properties of the developed nanopillared surfaces will be carried out using a Nanovea tribometer (Microphotonics, Irvine, CA)Task 2. Evaluate the effect of the developed surface on microbial adhesion and furthermore biofilm formation using various types of pathogenic microorganisms.The PI and Co-PI (Dr. Li) at UH will test the anti-microbial attributes of the developed nano-engineered surfaces using pathogens including E. coli, Salmonella Typhimurium., S. aureus, and L. monocytogenes at various wall shear rates. The detailed bacterial adhesion tests are in the following.1. E. coli, Salmonella Typhimurium, S. aureus, and L. monocytogenes cells will be separately cultured in tryptic soy broth (TSB) at 37°C for 24 h before used. Bacterial adhesion tests will be carried out on hydrophilic, hydrophobic, and slippery nano-engineered surfaces, all placed together side-by-side inside a parallel-plate flow channel. To perform the stagnant adhesion tests, the prepared bacterial suspensions will be held inside a pre-cleaned test chamber for 1, 5, 10, 18, 24, and 96 hrs. On the other hand, bacterial suspensions will individually pumped through the test chamber at various flow rates for dynamic adhesion test.3. The growth of biofilms on the proposed nanopillared surfaces can be monitored using an optical laser scanning microscope at the Biology Department. Biofilm culture will be prepared by incubation at 28°C with bacterial suspension and culture medium on the surfaces. Randomly selected biofilm samples from all replicates are thoroughly washed three times with 0.05 M phosphate buffer at pH 7.4. Each sample will be subsequently immersed in 1 mL solution of PBS for 5 min twice. For staining, samples will be added to 5 µL of 0.5% (w/v) fluorescein isothiocyanate (FITC) stock solution in 1 mL of PBS in the dark. Finally, samples will be washed with PBS and then fixed with 4% glutaraldehyde at room temperature for 1 hr. The scanning microscope will be used for the image analysis of samples.4. FITC and green fluorescent protein (GFP) with clear hydrophobic markers will be used to inspect their adhesion with the proposed hybrid surfaces and the control for a comparative study. A fluorescence microscopy (Nikon Ti-U inverted microscopy, Available in Dr. Li's lab) will be used to inspect the samples after they are incubated with FITC and GFP. ImageJ software, (NIH, Bethesda, Maryland) is used for image processing and analysis.Task 3. Study and develop the comprehensive model to elucidate the mechanics of microbial adhesion to the nanopillared surfaces with control factors such as surface wettability and slipperiness e.g. kinetics, cell-surface interaction theories (UH and SIT)1. A mathematical model to simulate the three-dimensional single bacterial attachment to nano-engineered surfaces (i.e. nanopillared) will be developed and tested with bacteria i.e. E. coli, Salmonella spp., S. aureus, and L. monocytogenes in different wall shear rates. The model combines accurate diffusion-reaction equations to simulate substrate diffusion with cellular automation-like criteria to model initial bacterial adhesion process as well as biofilm growth and colonization on solid substratum. Therefore, the cell-surface interactions e.g., attachment kinetics, effects of surface nano-topography, hydrophobicity, and slipperiness can be determined.2. The concentration of substrates in the bulk liquid simulates environmental conditions where bacterial biofilms can develop. Chemical species used in the model can be lactate, hydrogen, methane, acetate, bicarbonate, sulfate, and hydrogen sulfide, and the mass balance equation of a chemical species m in a biofilm element.3. The numerical optimization of the 3D model is based on the separation of the biological, physical, and chemical phenomena in three distinct steps: (a) diffusion of chemical species, (b) growth of biomass within each biofilm element, and (c) biofilm expansion and colonization. Commercial computational software i.e., COMSOL multiphysics will be used to calculate the transient concentration of chemical species and multiplication of cells within each biofilm element for a given time step, and distribute excess cells from overpopulated biofilm elements to neighboring elements.Task 4: Design pilot-scale washing equipment for fresh-produce processing and test anti-adhesion property of nano-engineered surfaces1. Designing of the pilot-scale washing station is necessitated for the use of less water and samples as well as to simulate a real-time situation when the proposed nano-engineered surface would be applied. The dimension of the developed unit will be approximately 2.5'´1'´1' and consist of air bubble jets, water recirculator, and sample loading area. The bottom surface will be tiled with two different surfaces (nanopillared and control surfaces). Flow characteristics, treatment time, and system schematics will be key parameters for effective adhesion testing of microbial contaminants on the surfaces.A typical versatile water system in fresh produce industries is a flood washer that has underwater jets with or without the use of chlorine. The proposed washing station will consist of holes on the sidewall where washing water will be sprayed through. High spray water injection through side holes will create water bubble effects to release microbial contaminants from fresh produce.2. Microbial testing: Experimental conditions can be defined as follows: (1) Only cabbages will be contaminated; (2) Only washing water (spiked with bacterial solution) will be contaminated; and (3) Both cabbages and washing water will be contaminated. Fresh produce washing in the pilot-scale equipment will be allowed to run for 1, 5, 10, 18, 24, 96 hrs. Thereafter, the same procedure as in Approach 2 will be repeated for bacterial adhesion testing. After draining washing water, individual pieces of nanopillared and control surfaces will be separated from the station base and subject for microbial counts and anti-biofilm tets.

Progress 01/15/15 to 01/14/19

Outputs
Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The current objective of this study was to design and test the efficiency of electrochemical etching combined with polytetrafluoroethylene (PTFE) coating in fabricating the superhydrophobic surfaces and to demonstrate the anti-adhesion effect against L. monocytogenes. 304 stainless steel coupons were cut into 25 × 20 × 0.2 mm specimens and each specimen was placed in a jacketed beaker parallel to a carbon plate at a distance of 5 cm. 200 mL of dilute aqua regia solution (3.6% HCl and 1.2% HNO3) was poured into the jacketed beaker and the temperature of the solution was maintained at 4°C by a circulating temperature controller. Constant electric potentials of 5, 10, and 15 V were applied for 5, 10, and 15 min by a DC power supply to manipulate pore sizes in a nanoscale. The substrates were rinsed in deionized water after etching and completely dried. The electrochemically etched coupons were coated with PTFE by dropping 1 mL of PTFE solution and baking on a hot plate at 110°C for 10 min, at 165°C for 5 min, and at 330°C for 15 min sequentially. The hydrophobicity of each specimen was measured by dropping a sessile water droplet (~5 μL) using a contact angle goniometer. For bacterial attachment experiments, L. monocytogenes were grown in 10 ml of TSB at 37°C for 24h. The cells were washed with phosphate-buffered saline (PBS) at pH 7.1-7.4 and collected by centrifugation at 4,000g for 20 min. 60 µl of L. monocytogenes in PBS (ca. 108 CFU/mL) were dropped on the stainless steel surfaces and stored at room temperature for 24 h. After the attachment, the specimens were vortexed in tubes containing 10 ml of PBS and 2g of sterile glass beads. The cell suspensions were tenfold serially diluted in 0.1% peptone water and PALCAM agar was used for enumeration. When the control stainless steel coupons were coated with PTFE, the water contact angle was approximately 117° which is close to the literature value (120°). This result showed that an increased surface roughness in the base substrate is needed to enhance the hydrophobicity and to decrease associated bacterial adhesion. The contact angle measurements of the stainless steel etched at 10 V for the duration of 5, 10, and 15 min separately, and at 15 V for 5 min and 10 min individually, increased more than other treatments by 20%. However, the contact angle did not meet the superhydrophobic surface characteristic (150°). In order to increase the hydrophobicity, an addition coating procedure for the fabricated nanoporous surface with a low surface energy material, PTFE was essential. When the nanoporous surfaces etched at 10 V for 5 min and at 10V for 10 min were subsequently coated with PTFE, the contact angle measurements were greater than 150°. The contact angle of the fabricated superhydrophobic surfaces increased more than the PTFE coated control samples by 24.2%. Exposure of smooth surface to L. monocytogenes resulted in 1.31×106 CFU/cm2 attachment. The nanoporous superhydrophobic surfaces (10V for 5 min with PTFE) reduced the adhesion of the bacterial cells by 1.76 log CFU/cm2. On the other hand, the nanoporous superhydrophobic surfaces (10V for 10min with PTFE) demonstrated a higher anti-adhesion properties by reducing the bacterial attachment by 2.02 log CFU/cm2. The performance of nanoporous surfaces (10V for 10 min with PTFE) in repelling L. monocytogenes showed a promising results with the possibility of reducing a potential hazard and an important source of contamination.

Publications

  • Type: Journal Articles Status: Submitted Year Published: 2019 Citation: Ban, G., Li, Y., and Jun, S. 2019. Nano-engineered stainless steel surface to combat bacterial attachment and biofilm formation. LWT - Food Science and Technology.
  • Type: Journal Articles Status: Submitted Year Published: 2019 Citation: Lee, J., Jiang, Y., Hizal, F., Ban, G-H., Jun, S., and Choi, C-H. 2019. Durable Omniphobicity of Oil-Impregnated Anodic Aluminum Oxide Nanostructured Surfaces. Journal of Colloid and Interface Science.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Ban, G., Rungraeng, N., Li, Y., and Jun, S. 2018. Nanoporous stainless steel surfaces for anti-bacterial adhesion performances. Trans of ASABE 61(3): 1-5
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Jun, S. 2018. Nano-engineered stainless steel surface to prevent biofilm formation of foodborne pathogens. Conference of Food Engineering (CoFE), September 9-12, Minneapolis, MN
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Jun, S. 2018. Nano-engineered surfaces guard against biofouling. Institute of Food Technologists (IFT), Chicago, IL


Progress 01/15/17 to 01/14/18

Outputs
Target Audience: Nothing Reported Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? We demonstrated nanofabrication and anti-biofilm characterization of the self-cleanable surface on stainless steel substrates. The 304 grade stainless steel was electrochemically etched in dilute Aqua Regia solution consisting of 3.6% HCl and 1.2% HNO3 at 10 V for 5, 10, and 15 min to fabricate hierarchical nanoporous structures. Difference in treatment durations led to variations in the etch rate and surface morphologic characteristics; the specimens treated at 10 V for 10 min showed nanoscale pores which are needed to improve the self-cleanability while maintaining the intrinsic food grade quality of stainless steel. The etched samples coated with an additional hydrophobic Teflon layer showed a maximum static water contact angle of 151°. Under static and realistic flow environments, Escherichia coli O157:H7 and Salmonella Typhimurium were used for testing antibacterial adhesion and antibiofilm performances of the developed surfaces. The populations of attached bacteria on the electrochemically etched stainless steel with Teflon coating were significantly reduced by 2.1-3.0 log CFU/cm2, as compared to the bacteria on bare stainless steel (P < 0.05), under both static and flow conditions.

Publications

  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Hizal, F., Rungraeng, N., Lee, J., Jun, S., Busscher, H.J., van der Mei, H.C., Choi, C-H. 2017. Nanoengineered Superhydrophobic Surfaces of Aluminum with Extremely Low Bacterial Adhesivity. ACS Applied Materials & Interfaces 9 (13), pp 1211812129
  • Type: Journal Articles Status: Accepted Year Published: 2018 Citation: Ga Hee, Ban, Natthakan, Rungraeng, Yong, Li, Soojin Jun,2018, Nanoporous stainless steel surfaces for anti-bacterial adhesion performances, Transactions of the ASABE
  • Type: Journal Articles Status: Submitted Year Published: 2018 Citation: Ga-Hee Ban, Yong Li, and Soojin Jun, 2018, Nano-engineered stainless steel surface to combat bacterial attachment and biofilm formation, Applied and Environmental Microbiology
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Ga-Hee Ban, Yong Li, and Soojin Jun, 2017, Fabrication of nano-engineered stainless steel to prevent biofilm formation of foodborne pathogens, International Association for Food Protection,July 9-12, Tampa, FL
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Ban, G-H., Lee, J., Choi, C-H., Li, Y., Jun, S. 2017. Effect of nano-patterned aluminum surface with oil-impregnation for antibacterial performance LWT - Food Science and Technology 84:1-5


Progress 01/15/16 to 01/14/17

Outputs
Target Audience:1) US food industries, as well as an academic network of food scientists/microbiologists 2) USDA, FDA and other federal/state/local food regulatory agencies 3) Nationwide food safety coordinators (food equipment hygiene, GMP, HACCP training) 4) A network of food nanotechnology professionals 5) A group of nanomaterials and nanofabrication specialists Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?The results of the research poster title "Nano-engineered sanitation Surfaces for Prevention of Bacterial Adhesion" were presented at conferences (IAFP 2016, Missouri; Conference of Food Engineering, Ohio) What do you plan to do during the next reporting period to accomplish the goals?We will demonstrate nanofabrication and anti-biofilm characterization of the self-cleanable surface on stainless steel substrates. The 304 grade stainless steels will be electrochemically etched in dilute Aqua Regia solution at various conditions such as voltages (5, 10, 15, and 20 V) and treatment times (5, 10, 15, and 20 min) to fabricate hierarchical nanoporous structures. Under static and dynamic flow environments, E. coli, S. Typhimurium, Listeria monocytogenes, and Pseudomonas aeruginosa PAO1 will be used for testing antibacterial adhesion and antibiofilm performances of the developed surfaces. The successful fabrication of superhydrophobic etched surfaces can be used in food industries to prevent biofilm development, resulting in the improvement of food safety.

Impacts
What was accomplished under these goals? Extensive research has been reported to improve the performance of existing antibacterial surfaces by reducing the extent of bacterial adhesion and biofilm formation. This study was performed (1) to validate the oil-impregnation method for the prevention of bacterial attachment on nano-patterned aluminum surface, (2) to develop the etching technique for the fabrication of a nanoporous surface on stainless steel to prevent biofilm formation, and (3) to design a microbial resistant pilot-scale washing station for application of developed nanoporous surface. (1) Four types of AAO samples including small pore (SPo), large pore (LPo), single pillar (SPi), and bundle pillar (Bpi) were fabricated with oil-impregnation. The Teflon coated AAO with oil-impregnation repels water with sliding angles as low as 3° even though it did not show hydrophobicity. Bacterial attachment tests using Escherichia coli K-12 and Salmonella Typhimurium were conducted to evaluate the effect of antibacterial performance on the developed surfaces. Teflon coated AAO with oil-impregnation showed the highest bacterial reductions for both E. coli K-12 and S. Typhimurium. (2) The 304 grade stainless steels are electrochemically etched in dilute Aqua Regia solution consisting of 3.6% HCl and 1.2% HNO3 at 10 V for 10 min to fabricate hierarchical nanoporous structure. The etched samples showed hydrophobicity in terms of a static water contact angle of 133°. (3) The miniaturized washing station for fresh produce was designed using Auto-CAD to simulate a real-time situation when the proposed nano-engineered surface would be applied. The dimension of the developed unit is 90 cm ×30 cm ×30 cm (3'×1'×1') and the exterior and sidewall thickness of the chamber is 1 cm. The equipment consists of conveyor belt, washing zone, bubble jets, and sample loading area. These results can be attributed to further optimization of nano-patterned surfaces for antibacterial attachment.

Publications

  • Type: Journal Articles Status: Published Year Published: 2016 Citation: Hizal, F., Choi, C-H., Busscher, H.J., van der Mei, H.C. 2016. Staphylococcal adhesion, detachment and transmission on nanopillared Si surfaces. ACS Applied Materials & Interfaces 8, 3043030439.
  • Type: Journal Articles Status: Submitted Year Published: 2016 Citation: Hizal, F., Rungraeng, N., Lee, J., Jun, S., Busscher, H.J., van der Mei, H.C., Choi, C-H. 2016. Nanoengineered Superhydrophobic Surfaces of Aluminum with Extremely Low Bacterial Adhesivity. ACS Applied Materials & Interfaces
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Ban, G-H., Lee, J., Lee, J., Kang, Y. Li, Y., Choi, C-H., and Jun, S. 2016. Nano-engineered sanitation surfaces for prevention of bacterial adhesion. Conference of Food Engineering, Ohio, USA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2016 Citation: Ban, G-H., Lee, J., Lee, J., Li, Y., Choi, C-H., and Jun, S. 2016. Nano-engineered sanitation surfaces for prevention of bacterial adhesion. IAFP Annual Meeting - International Association for Food Protection. Missouri.
  • Type: Journal Articles Status: Submitted Year Published: 2016 Citation: Ban, G-H., Lee, J., Choi, C-H., Li, Y., Jun, S. 2017. Effect of nano-patterned aluminum surface with oil-impregnation for antibacterial performance LWT - Food Science and Technology.


Progress 01/15/15 to 01/14/16

Outputs
Target Audience:1. US food industries as well as an academic network of food scientists/microbiologists 2. USDA, FDA and other federal/state/local food regulatory agencies 3. Nationwide food safety coordinators (food equipment hygiene, GMP, HACCP training) 4. A network of food nanotechnology professionals 5. A group of nanomaterials and nanofabrication specialists Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Extensive efforts have been focused on the performance improvement of existing antibacterial surfaces in order to eliminate the extent of bacterial adhesion and biofilm formation. This study was intended to (1) explore the effect of nanoscale-patterned stainless steel on bacterial adhesions and (2) validate fabrication of the oil impregnated nanoporous surface and its application to food processing equipment. Nanosmooth (control) and nanoporous stainless steel surfaces were fabricated by anodizing the degreased specimen in a 5% vol. of perchloric acid in anhydrous ethylene glycol. The presence of nanoscale surface patterns on stainless steel significantly inhibited adhesion of foodborne pathogens. It was observed that the thickness of porous anodic oxide films of stainless steel increased with increased anodization time (an average growth rate = ~50 nm/min). As a parallel approach, oil impregnated surfaces were developed using the pore-widening treatment. Fabrication of nanoporous oxides is a key technology for oil impregnated slippery surface on metallic materials. Four types of anodic aluminum oxide (AAO) including small pore AAO (SPo), large pore AAO (LPo), single pillar AAO (SPi), and bundle pillar AAO (Bpi) were fabricated for oil impregnation. The porosity of AAO increased with the pore-widening time, thereby reducing surface solid fractions. It was found that LPo structure enabled to facilitate the slipperiness superior to others in terms of apparent contact angle, contact angle hysteresis, and a sliding angle of oil impregnated surface and dry surface (without oil).

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Rungraeng, N. and Jun, S. 2015. Nanoscale Patternings on Stainless Steel Surfaces for Prevention of Bacterial Adhesion. The 2015 IFT Annual Meeting, July 11-14, Chicago, IL (099-100)
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Jun, S. 2015. Food nanotechnology for biosensing and biofilm prevention. 2015 International Symposium and Annual Meeting at Alpensia Resort Convention Center, Pyeongchang, South Korea, August 24 -26.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2015 Citation: Jun, S. 2015. Nano-engineered surfaces for prevention of biofilm and bacterial adhesion. The 82nd Annual Meeting of Korean Society of Food Science and Technology (KoSFoST) at Bexco Convention Center, Busan, Republic of Korea, June 3 -5.