Rapid and Accurate Quantification of Viable Lactobacillus Cells in Infant Formula by Flow Cytometry Combined with Propidium Monoazide and Signal-Enhanced Fluorescence In Situ Hybridization

Lactobacillus is an important member of the probiotic bacterial family for regulating human intestinal microflora and preserving its normalcy, and it has been widely used in infant formula. An appropriate and feasible method to quantify viable Lactobacilli cells is urgently required to evaluate the quality of probiotic-fortified infant formula. This study presents a rapid and accurate method to count viable Lactobacilli cells in infant formula using flow cytometry (FCM). First, Lactobacillus cells were specifically and rapidly stained by oligonucleotide probes based on a signal-enhanced fluorescence in situ hybridization (SEFISH) technique. A DNA-binding fluorescent probe, propidium monoazide (PMA), was then used to accurately recognize viable Lactobacillus cells. The entire process of this newly developed PMA-SEFISH-FCM method was accomplished within 2.5 h, which included pretreatment, dual staining, and FCM analysis; thus, this method showed considerably shorter time-to-results than other rapid methods. This method also demonstrated a good linear correlation (R2 = 0.9994) with the traditional plate-based method with a bacterial recovery rate of 91.24%. To the best of our knowledge, the present study is the first report of FCM combined with PMA and FISH for the specific detection of viable bacterial cells.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:96

Enthalten in:

Analytical chemistry - 96(2024), 3 vom: 23. Jan., Seite 1093-1101

Sprache:

Englisch

Beteiligte Personen:

Wang, Chenglong [VerfasserIn]
Liu, Siyuan [VerfasserIn]
Wang, Ziquan [VerfasserIn]
Wang, Meng [VerfasserIn]
Pang, Huimin [VerfasserIn]
Liu, Yingying [VerfasserIn]
Chang, Haiyan [VerfasserIn]
Sui, Zhiwei [VerfasserIn]

Links:

Volltext

Themen:

36015-30-2
Azides
Journal Article
Propidium
Propidium monoazide
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 24.01.2024

Date Revised 20.02.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1021/acs.analchem.3c03742

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM36694763X