TITLE:
Application of GFPuv Labeled Cronobacter sakazakii for Evaluation of Its Survival during Cornstarch Processing
AUTHORS:
Siti Nurjanah, Sarah Tiara Sulistyanti, Ratih Dewanti-Hariyadi
KEYWORDS:
Cronobacter sakazakii, Cornstach, Green Fluorescent Protein, Processing, Survival
JOURNAL NAME:
World Journal of Engineering and Technology,
Vol.3 No.3B,
August
25,
2015
ABSTRACT: Cronobacter sakazakii is an emerging
pathogen that can cause diseases for several infant groups. These bacteria were
contaminated in foods, clinical utensils, and environments. In Indonesia, C.
sakazakii has been isolated from powdered infant formulas, weaning foods, and
other dried foods such as cornstarch. The objective of this research is to
trace survival of C. sakazakii during cornstarch production step using its
mutant. Mutant was constructed by inserting Green Fluorescent Protein plasmid
inside to the bacterial cell that appeared green fluorescent colonies under UV
observation. The presence of C. sakazakii during processing was conducted by
artificial contamination. This research consists of three steps, i.e.
determination of the suitable enumeration method of C. sakazakii’s mutant,
cornstarch production from yellow corn, and survival analysis of C. sakazakii
during endosperm soaking and cornstarch drying. The suitable enumeration method
was surface plating method on TSA-ampicillin medium combining with UV light
application because of ineffectiveness of ampicillin inhibition for growth of
yeasts and molds. The cornstarch produced in laboratory has the same properties
with commercial cornstarch in parameters of moisture content, density, and
starch granule structure. The yield of cornstarch final product was 48.90% (dry
whole kernel-based). C. sakazakii cannot survive in 48 hours soaking process at
52?C and 24 hours drying process at 50?C that is applied during cornstarch
production.