Table 2.

Research that demonstrated the probiotic potential of enterococcal strains and their key functions.

Probiotic Potential	Type of Research	Enterococcal Strains	Functions	Reference
Acute Diarrhea	A placebo-controlled trial in adults	E. faecium SF68	Significantly shorter duration of acute diarrhea with no adverse drug reactions	Buydens et al. 1996 [26]
	A placebo-controlled trial in pediatrics	E. faecalis (in BIO-THREE®)	Significantly shorter duration of acute diarrhea and hospital stay Decreased levels of cytokines IL-10, TNF-α, IFN-γ, and IL- 12	Chen et al. 2010 [27]
Irritable Bowel Syndrome (IBS)	Open-label trial in adults	Enterococcus (non-specified strain)	Improvement of IBS symptoms Reduction of enterococcal count (p < 0.01) and count of Bacteroides (p < 0.05) in the intestinal flora	Fan et al. 2006 [28]
	Open-randomized placebo-controlled trial	E. faecium ENCFa68	Improved clinical manifestations of the disease Restoration of the normal composition of intestinal microbiota and normalization of the content of fecal calprotectin	Yakovenko et al. 2022 [29]
Gastrointestinal Inflammation	Mice	5 Enterococcus strains (not specified)	Reduced intestinal epithelial permeability by increasing stimulation of tight junctions Reduced inflammation	Ahmadi et al. 2020 [30]
Allergic Rhinitis (AR)	A placebo-controlled trial in pediatrics	E. faecium L3 LMG P27496	Reduced symptoms of AR Significant reduction in nasal symptom score Significant reduction in intake of pharmacological therapy (antihistamines and local steroids)	Anania et al. 2021 [31]
Chronic Recurrent Bronchitis	Double-blind, placebo-controlled multicenter trial	E. faecalis (in Symbioflor 1)	Significant reduction of the duration until relapse Significant reduction in the need for antibiotics	Habermann et al. 2001 [32]
Salmonellae-infections	Piglets	E. faecium NCIMB 10415	Increased number of intraepithelial lymphocytes (IEL), which are potentially related to the early detection of pathogenic bacteria	Rieger et al. 2015 [33]
Atopic respiratory symptoms	Retrospective trial in pediatrics	E. faecium L3	Significant reduction of rhinitis, watery eyes, and cough/bronchospasm Significant reduction of need for drugs (e.g., antihistamines, corticosteroids)	Di Pierro et al. 2018 [34]
Acute Respiratory Infections (ARI)	Observational research on orphan infants	E. faecium L3	Reduction of ARI cases	Gonchar et al. 2015 [35]
Hyperlipidemia	Randomized placebo-controlled human volunteers	E. faecium M74	Reduction in LDL cholesterol	Hlivak et al. 2005 [36]
		E. faecium (non-specified strain)		Agerbaek et al. 1995 [37]