Improved Design of Automatic Luminometer for Total Bacteria Number Detection Based on ATP Bioluminescence. Issue 1 (4th January 2013)

• Record Type: Journal Article
• Authors: Yue, Weiwei; Bai, Chengjie
• Is Part Of: Journal of food safety. Volume 33:Issue 1(2013:Jan.)
• Page Start: 1
• Page End: 7
• Publication Date: 2013-01-04
• Subjects: Food adulteration and inspection -- Periodicals; Food contamination -- Periodicals; Food -- Analysis -- Periodicals; Food -- Microbiology -- Periodicals; Pathogenic bacteria -- Periodicals; Food handling -- Periodicals; Food preservatives -- Periodicals; 664
• DOI: 10.1111/jfs.12016
• Languages: English
• ISSNs: 0149-6085

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <sec id="jfs12016-sec-0001" sec-type="section"> <p>An improved design of automatic luminometer for rapid detection of total bacterial number by adenosine 5′‐triphosphate (ATP) bioluminescence was developed. To reduce the impact of bioluminescence absorption and scattering, an automatic optical calibration unit was embedded into the luminometer. An automatic injection unit was integrated to add reaction reagents automatically for accuracy of quantitative reagents and reaction time. The original data of bioluminescence intensity were fitted to improve the detection range of the improved luminometer. After calibration using bacterial suspension containing known quantity of <italic>Escherichia coli</italic> and <italic>Staphylococcus aureus</italic>, the improved luminometer was used to measure more than 500 food samples. The results showed a satisfactory linear response (<italic>R</italic> = 0.858) when comparing with the results of conventional plate count method in the bacterial concentration range from 10 to 10<sup>8</sup> cfu/mL. The reproducibility of the luminometer was tested by 12 tests of standard <italic>E. coli</italic> and <italic>S. aureus</italic> suspension and the coefficient variation was 8.1%.</p> </sec> <sec id="jfs12016-sec-0002" sec-type="section"> <title>Practical Applications</title> <p>Based on the principle of ATP bioluminescence technology, an improved automatic luminometer was presented in this paper to detect bacterial numbers in food samples. Through data fitted based on ATP bioluminescence reaction kinetics and optical calibration, the measurement range of bacterial numbers could be improved to 10–10<sup>8</sup> cfu/mL. More than 500 actual food samples including meat products, dairy products, drink, condiment, candy, and paddy and so on, were selected and the numbers of bacteria were measured by the luminometer. The results demonstrated a good linear relationship with a correlation coefficient of 0.858. Therefore, we propose that the improved design of luminometer in this paper has good potential to detect bacteria in food products to assist the safety assessment in food industry in practical applications.</p> </sec> </abstract>