OUHK Technical Seminar on Methodology and Technology in Microbiology Testing

The Technical Seminar named “Methodology and Technology in Microbiology” which jointly organized by The School of Science and Technology, The Open University of Hong Kong (OUHK), and Bio-Gene Technology Ltd. on 11 Feb 2015. The summary was shown below.

In the beginning, Dr. George HK LAU (Programme Leader & Associate Professor, Testing and Certification, School of Science & Technology, OUHK) gave a welcoming address. He introduced the new campus named Jubilee College and it was mainly for full time students. Then he introduced OUHK programme about T&C industry.

Group photo of all speakers and representatives of organizers
(Left: Dr. Fred LEE , Dr. George HK LAU, Ms. Mos Mo, Representative of Bio-gene, Mr. Kent W.K. Leung and Prof. KC Ho (Dean, School of Science and Technology, OUHK))

The first speaker was Dr. Fred LEE (Assistant Professor, School of Science and Technology, OUHK) and his topic entitled “The Research and Development in Microbiological Testing”. Firstly, Dr. Lee introduced different microbiological testing technologies and its development trend. Then he discussed each technology limitations and challenges.

Dr. Lee briefed different food safety incidents which related to microbiology. One of famous incidents was Legionella bacteria that found in Hong Kong government’s new headquarters in 2012. Then he introduced some common microbiological testing included Aerobic Colony Count (ACC), E. coil count, Salmonella spp., Listeria monocytogenes, E.coil O157:H7, Straphylococus aureus, etc.

Dr. Lee explained from traditional and classical analysis to instrumentation analysis because of the expectation on rapid, automation, ease to use, sensitively, specificity, cost effective and high-throughput. Then he introduced modern technologies as follows.
Serological – based technology
It related to antigen and antibody reaction such as Enzyme-Linked ImmunoSorbent Assay (ELISA).

Mass spectrometric (MS) – based technology
Rapid identification of food pathogenic and spoilage bacteria by MS fingerprinting was discussed (e.g. Matrix-assisted laser desorption / ionization (MALDI))

Molecular – based technology
Dr. Lee introduced different molecular analysis techniques included Polymerase Chain Reaction (PCR) / Real-time PCR, Gene probes / array and Metagenomic.

Finally, Dr. Lee concluded the challenges and limitations included Validation such as standard reference culture techniques, Viable or not, Training & Expertise, Cost, Regulation Approval, Reference materials and Harmonized Standard Methods.

The second speaker was Mr. Kent W.K. Leung (Technical Service Specialist, Techincal Dept., 3M HK Ltd.) and his presentation named “Rapid Technology in Food Safety”. Mr. Leung introduced the global trend of environmental monitoring for different targets included Pathogenic Organisms (e.g. Listeria, Salmonella), Indicator Organisms (e.g. Enterobacteriaceae) and Rapid Hygiene Monitoring (e.g. ATP, Protein).

Mr. Kent Leung said the trend for food safety strategy was from Detection to Prevention. There was an increased use of environment monitoring as a means to verify the prerequisite programs of HACCP; because 70% chance of organism was found from environment which contaminated our food. Therefore, the sampling focus should be on the most critical area of the plant. In addition, the diligent search for the pathogen needed to be part of Food Safety Culture of the facility. The following diagram demonstrated different pathogen test methods.

Then Mr. Leung mentioned 3M Petrifilm Plate and compared with Traditional Agar FDA BAM Method. It was found that 3M Petrifilm Plate and Disk Method used about 55hr to get the confirmation result of salmonella but the traditional one used upto 150hr (~3 times of Disk Method!).

Moreover, Mr. Leung introduced a better technology named Isothermal DNA Amplification (compared with PCR) and Bioluminescence Detection which used Adenosine Tri Phosphate (ATP) to generate light which was detected, indicating target DNA. The ATP detection principle was shown as follows.

One challenge of ATP detection was not the same response in different brand of ATP detection systems. It needed to create harmonization group to align it because it seemed to be the fastest detection techniques (~10s). (where PCR about 1 to 2 hr). Finally, Mr. Kent Leung concluded that the best strategy could involve a COMBINATION of pathogen, indicator and rapid hygiene indications for environmental monitoring.

The last speaker was Ms. Mos Mo (Regional Marketing Manager, Laboratory Business Asia, Pall Filtration Pte Ltd.) and her presentation topic was “Microbiology QC for Water of Pharmaceutical Purpose”.

Firstly, Ms. Mo briefed microbiology QC requirements in Manufacture, Environment and Testing Laboratory. Then she reviewed plate counts and MPN (Most Probable Number) methods. The following two diagrams showed different requirement from US Pharmacopoeia.

She said the chapter number below 1000 was mandatory requirement. The chapter number larger than 1000 was guidance.

The tracking of microbe diagram was shown as follows. It included “Raw Material, Bulk Equipment, Area, Water, Container Closure, Personnel” to “Bulk Preparation”, and then “Filtration and Filling”, end at “Sterile Products Release” and “Non-sterile Products Release”.

Finally, she discussed the water quality types and validation using USP <1231>. Based on ASTM standard, it considered Resistivity (MOhm.cm at 25C), pH, TOC (ppb) and Bacteria (cfu/100ml).
Type I   : 18.0,    NA,     50,     <1
Type II  : 1.0,      NA,     50,     <10
Type III : 4.0,      NA,    200,    <100

After that we performed Microbiology QC Contest.

Even though our team lost, we still had souvenir.

Reference:
OUHK - http://www.ouhk.edu.hk/
Bio-Gene - http://www.bio-gene.com.hk/