Update of the list of qualified presumption of safety (QPS) recommended microbiological agents intentionally added to food or feed as notified to EFSA 18: Suitability of taxonomic units notified to EFSA until March 2023
Abstract:The qualified presumption of safety (QPS) approach was developed to provide a regularly updated generic pre‐evaluation of the safety of microorganisms, intended for use in the food or feed chains, to support the work of EFSA's Scientific Panels. The QPS approach is based on an assessment of published data for each agent, with respect to its taxonomic identity, the body of relevant knowledge and safety concerns. Safety concerns identified for a taxonomic unit (TU) are, where possible, confirmed at the species/s… Show more
“…However, in this study, the use of the oligonucleotide probe was slightly timeconsuming. To decrease the TTR of the PMA-SEFISH-FCM method, the different conditions of fixation time (15, 30, 45, 60, 75, and 90 min) and hybridization time (10,20,30,40,50, and 60 min) were compared, while other conditions were kept constant. The optimized conditions should provide more stained cells and ensure that most of the events that represent Lactobacillus cells were located at the well-setting gate in the associated dot plots.…”
Section: ■ Resultsmentioning
confidence: 99%
“…Table S1 shows the 34 bacterial strains used in this study. This included 19 Lactobacillus strains selected for inclusivity detection, which cover all Lactobacillus strains mentioned in the list of qualified presumption of safety (QPS)-recommended biological agents …”
Section: Methodsmentioning
confidence: 99%
“…This included 19 Lactobacillus strains selected for inclusivity detection, which cover all Lactobacillus strains mentioned in the list of qualified presumption of safety (QPS)-recommended biological agents. 20 Lactobacilli rhamnosus GG was used as the target strain. Fifteen non-Lactobacillus strains were used to evaluate exclusivity.…”
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 (R 2 = 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.
“…However, in this study, the use of the oligonucleotide probe was slightly timeconsuming. To decrease the TTR of the PMA-SEFISH-FCM method, the different conditions of fixation time (15, 30, 45, 60, 75, and 90 min) and hybridization time (10,20,30,40,50, and 60 min) were compared, while other conditions were kept constant. The optimized conditions should provide more stained cells and ensure that most of the events that represent Lactobacillus cells were located at the well-setting gate in the associated dot plots.…”
Section: ■ Resultsmentioning
confidence: 99%
“…Table S1 shows the 34 bacterial strains used in this study. This included 19 Lactobacillus strains selected for inclusivity detection, which cover all Lactobacillus strains mentioned in the list of qualified presumption of safety (QPS)-recommended biological agents …”
Section: Methodsmentioning
confidence: 99%
“…This included 19 Lactobacillus strains selected for inclusivity detection, which cover all Lactobacillus strains mentioned in the list of qualified presumption of safety (QPS)-recommended biological agents. 20 Lactobacilli rhamnosus GG was used as the target strain. Fifteen non-Lactobacillus strains were used to evaluate exclusivity.…”
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 (R 2 = 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.
“…The use of strains of microorganisms belonging to a species that qualifies for the QPS approach (EFSA, 2007 ; EFSA BIOHAZ Panel, 2023 ) and for which the qualifications were met, are considered safe for the animals, humans and, if relevant, for the environment and therefore no further data are required.…”
Section: Data Required For the Evaluation Of Feed Detoxification Proc...mentioning
This statement provides scientific guidance on the information needed to support the risk assessment of the detoxification processes applied to products intended for animal feed in line with the acceptability criteria of the Commission Regulation (EU) 2015/786.
“…Many LAB (including species: Lactobacillus , Lactiplantibacillus , Ligilactobacillus , Lactococcus , and Leuconostoc ) have been granted Qualified Safety Presumption status by the European Food Safety Authority and GRAS status (generally recognized as safe) by the U.S. Food and Drug Administration. This recognition is attributed to their extensive history of safe use in fermented foods and their presence in the normal intestinal and urogenital microbiota of both humans and animals ( 9 , 10 ). Furthermore, some LAB species are acknowledged as probiotics, organisms whose short-term presence or colonization positively influence many elements of the host’s physiology.…”
Transcriptomic analysis of the genome sequenced
Ligilactobacillus salivarius
strain IBB3154 grown at two different temperatures (37°C vs 42°C) identified differentially expressed genes involved in metabolic pathways, osmoregulation, and surface protein expression. Two highly expressed genes,
sasA1
and
sasA2
, which encode cell wall-anchored proteins belonging to the serine-rich repeat protein group, were found to be temperature-inducible. Moonlighting proteins with various functions, such as glyceraldehyde 3-phosphate dehydrogenase, fructose-bisphosphate aldolase, elongation factor Tu, and enolase, were highly expressed at both temperatures. The efficiency of promoters has been confirmed by the β-glucuronidase activity test; however, temperature dependence was not detected. We also found that the P
sasA1
promoter retained its activity in the presence of bile salts. Knowledge of promoters that are highly active in
L. salivarius
cells can be used to produce strains that are carriers of immunogenic proteins.
IMPORTANCE
The genome of the strain
Ligilactobacillus salivarius
IBB3154 was sequenced, and transcriptome analysis was carried out at two different temperatures, allowing the determination of gene expression levels in response to environmental changes (temperature). Genes with higher expression at 42°C were identified. The use of a reporter gene (β- glucuronidase) did not confirm the transcriptomic results; it was found that the promoters of the genes
sasA1
and
sasA2
were active in the presence of bile salts. This opens up new opportunities for the overexpression of genes of other bacterial species in
Ligilactobacillus
cells in the intestinal environment.
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