Functional Profile Evaluation of Lactobacillus fermentum TCUESC01: A New Potential Probiotic Strain Isolated during Cocoa Fermentation

In vitro adhesion and anti-inflammatory properties of Limosilactobacillus fermentum FS-10 isolated from infant fecal sample

In this study, seven strains of Limosilactobacillus fermentum were isolated from an infant fecal sample and characterized using in vitro studies. Lactobacillus rhamnosus GG was used as a comparison because it is a well-documented commercial probiotic. The isolates were tested for attributes such as acid and phenol tolerance, bile salt hydrolase (BSH) activity, and antibiotic sensitivity. One isolate, L. fermentum FS-10, displayed enhanced cell surface hydrophobicity (> 85%) and mucin adhesion. Mucin-binding helps colonization in the gut. The immunomodulatory property of L. fermentum FS-10 was evaluated by determining the modulation of pro- and anti-inflammatory factors such as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-10, and nitric oxide (NO) in human acute monocytic leukemia (THP-1) cells under inflammatory conditions induced by lipopolysaccharide (LPS). L. fermentum FS-10 potently downregulated the expression of TNF-α and nitric oxide and upregulated IL-10 levels, indicating an anti-inflammatory response. Safety assessment of the strain revealed the absence of genes for virulence factors, toxin production, and antibiotic resistance, potentiating application as a probiotic strain.

Exploration of probiotic attributes in lactic acid bacteria isolated from fermented Theobroma cacao L. fruit using in vitro techniques

Probiotics are known for their health-promoting properties and are recognized as beneficial microorganisms. The current investigation delves into the isolation and comprehensive in vitro characterization of lactic acid bacteria (LAB) obtained from the Indian-origin Theobroma cacao L. Forastero variety to assess their potential as probiotic candidates. Eleven LAB isolates were obtained, and among them, five exhibited classical LAB traits. These five isolates underwent rigorous in vitro characterization to evaluate their suitability as probiotics. The assessments included resilience against acid and bile salts, which are crucial for probiotic viability. Additionally, the isolates were subjected to simulated gastric and pancreatic fluids and lysozyme exposure to assess their survival rates. Auto- aggregation, co-aggregation, hydrophobicity, and exopolysaccharide production were also examined. The inhibitory potential of α-glucosidase, an enzyme related to glucose metabolism, was measured, and antioxidant activity was evaluated using DPPH and ABTS assays. A safety assessment was conducted to confirm the non-pathogenic nature of the isolates. Among the five isolates, CR2 emerged as a standout candidate with maximal bile salt hydrolase activity, phenol resistance, and lysozyme resistance. CR2 and CYF3 exhibited notable survival rates under simulated conditions. The isolates displayed variable degrees of auto-aggregation, co-aggregation, and hydrophobicity. CR2 exhibited the highest exopolysaccharide production (0.66 mg/mL), suggesting diverse applications in the food industry. CR2 also demonstrated the highest inhibition rate against α-glucosidase (56.55%) and substantial antioxidant activity (79.62% DPPH, 83.45% ABTS). Safety assessment confirmed the non- pathogenic nature of the isolates. Molecular characterization identified CR2 as Lactococcus lactis subsp. lactis and CYF3 as Limnosilactobacillus fermentum. Both strains exhibited commendable probiotic and technological attributes, positioning them as promising candidates for functional foods and beyond. This study provides valuable insights into the in vitro characterization of LAB isolated from Indian Theobroma cacao L., highlighting their potential as probiotic candidates with advantageous traits, including survival in hostile conditions, beneficial enzymatic activities, bioactivity, and other essential attributes.

Whole Genome Sequencing of the Novel Probiotic Strain Lactiplantibacillus plantarum FCa3L

Lactiplantibacillus plantarum is best known for its significant adaptive potential and ability to colonize different ecological niches. Different strains of L. plantarum are widely used as probiotics. To characterize the probiotic potential of the novel L. plantarum FCa3L strain isolated from fermented cabbage, we sequenced its whole genome using the Illumina MiSeq platform. This bacterial isolate had a circular chromosome of 3,365,929 bp with 44.3% GC content and a cyclic phage phiX174 of 5386 bp with 44.7% GC content. The results of in vitro studies showed that FCa3L was comparable with the reference probiotic strain L. plantarum 8PA3 in terms of acid and bile tolerance, adhesiveness, H₂O₂ production, and acidification rate. The strain 8PA3 possessed higher antioxidant activity, while FCa3L demonstrated superior antibacterial properties. The antibiotic resistance of FCa3L was more relevant to the probiotic strain than that of 8PA3, although a number of silent antibiotic resistance genes were identified in its genome. Genomic evidence to support adhesive and antibacterial properties, biosynthesis of bioactive metabolites, and safety of FCa3L was also presented. Thus, this study confirmed the safety and probiotic properties of L. plantarum FCa3L via complete genome and phenotype analysis, suggesting its potential as a probiotic, although further in vivo investigations are still necessary.

Alarming Antibiotic Resistance of Lactobacilli Isolated from Probiotic Preparations and Dietary Supplements

In this study, we screened eight commercially available brands of Lactobacillus-containing probiotic preparations and dietary supplements for resistance towards commonly administered antibiotics of different classes. According to disc diffusion results, most of the isolates were resistant to vancomycin and susceptible to penicillin-type antibiotics (ampicillin and amoxicillin), carbapenems (imipenem, meropenem, and ertapenem), and inhibitors of protein synthesis (chloramphenicol, erythromycin, tetracycline, clarithromycin, and linezolid). However, based on minimum inhibitory concentration (MIC) values, six strains were reconsidered as resistant to tetracycline. All tested lactobacilli were resistant towards amikacin, ciprofloxacin, and norfloxacin. Resistance to cephalosporins was highly variable and decreased in the following order: ceftazidime/cefepime, ceftriaxone, cefotaxime, cefazolin, and cefoperazone. PCR screening for antibiotic resistance determinants in probiotic lactobacilli revealed a wide occurrence of vancomycin resistance gene vanX, ciprofloxacin resistance gene parC, and extended-spectrum β-lactamase gene blaTEM. We also detected the tetK gene for tetracycline resistance in one isolate. Additionally, we identified discrepancies between the claims of the manufacturers and the identified species composition, as well as the enumerated amount of viable bacteria, for several products. The results of this study raise concerns about the safety of lactobacilli for human consumption as probiotics, as they may act as reservoirs of transferable antibiotic resistance genes.

Characterization and evaluation of anti-Salmonella enteritidis activity of indigenous probiotic lactobacilli in mice

Lactobacilli (n = 24), isolated from human infants and yogurt, showed variable in vitro activity against Salmonella enteritidis (8.0 ± 1.0 to 16.6 ± 0.5 mm) and other gut pathogens (9.0 ± 1.0 to 15.3 ± 0.5 mm), as determined by a well diffusion assay. The isolates were identified as Limosilactobacillus fermentum (FY1, FY3, FY4, IL2, and IL5), Lactobacillus delbrueckii (FY6 and FY7), Lactobacillus sp. (IL7), and Lactobacillus gasseri (IL12). All isolates showed variable in vitro tolerance to acidic pH for 3 h and visible growth at pH 4 and in the presence of 0.3% ox-bile. The antibiotic susceptibility profile of Lactobacillus isolates indicated resistance against vancomycin, ciprofloxacin, streptomycin, and lincomycin. Isolates had variable auto-aggregation and showed variable capabilities to co-aggregate with S. enteritidis. Based on all tested parameters, L. fermentum IL2, L. fermentum IL5, and L. gasseri IL12 were selected for co-culture experiments, followed by in vivo evaluation in Balb/c mice. All the selected isolates resulted in a 100% reduction in S. enteritidis in broth. Lactobacillus isolates efficiently colonized mouse guts and inhibited S. enteritidis colonization. Overall, there was ≥99.06% and ≤4.32 Mean log₁₀ reduction in Salmonella counts in mice feces within 7 days. The study, thus, provided characterized lactobacilli that could be considered as potential ingredients for probiotic formulations intended to prevent S. enteritidis infection in humans.

Investigating the biotechnological potential of lactic acid bacteria strains isolated from different Algerian dairy and farm sources

Currently, consumption of spontaneously fermented milks is common in Algeria, making it a feasible source of diverse lactic acid bacteria (LAB) with the potential to be used as adjunct cultures to improve quality and safety of fermented dairy products. In this context, to select eligible indigenous strains which could be applied as bioprotective and/or starter cultures, the present study aimed to characterize the genomic variability, biotechnological potential, and safety of thirty-eight LAB isolated from Algerian dairy and farm sources of western Algeria. The isolates were unequivocally identified by 16S rRNA gene and fingerprint-based methods. The following species were identified: Enterococcus faecium (n = 15), Enterococcus durans (n = 2), Enterococcus hirae (n = 2), Enterococcus lactis (n = 1), Lactiplantibacillus plantarum (n = 6), Lactococcus lactis (n = 4), Levilactobacillus brevis (n = 3), Lacticaseibacillus paracasei (n = 3), Lacticaseibacillus rhamnosus (n = 1), and Pediococcus acidilactici (n = 1). Among the strains, three of them, L. lactis LGMY8, Lb. plantarum LGMY30 and Lb. paracasei LGMY31 were safe and showed some valuable biotechnological properties, such as high acidification, proteolytic activity, EPS production, and inhibition of undesirable bacteria that made them powerful candidates to be used as starter.

Lactic Acid Bacteria Diversity and Characterization of Probiotic Candidates in Fermented Meats

Probiotics are defined as live microorganisms which confer health benefits to the host when administered in adequate amounts. Many lactic acid bacteria (LAB) strains have been classified as probiotics and fermented foods are an excellent source of such LAB. In this study, novel probiotic candidates from two fermented meats (pancetta and prosciutto) were isolated and characterized. LAB populations present in pancetta and prosciutto were evaluated and Lactiplantibacillus plantarum was found to be the dominant species. The antagonistic ability of selected isolates against LAB and non-LAB strains was investigated, in particular, the ability to produce anti-microbial compounds including organic acids and bacteriocins. Probiotic characteristics including antibiotic susceptibility, hydrophobicity and autoaggregation capacity; and ability to withstand simulated gastric juice, bile salt, phenol and NaCl were assessed. Among the characterized strains, L. plantarum 41G isolated from prosciutto was identified as the most robust probiotic candidate compared. Results from this study demonstrate that artisanal fermented meat is a rich source of novel strains with probiotic potential.

Lactiplantibacillus plantarum strains isolated from spontaneously fermented cocoa exhibit potential probiotic properties against Gardnerella vaginalis and Neisseria gonorrhoeae

Background

Probiotics are important tools in therapies against vaginal infections and can assist traditional antibiotic therapies in restoring healthy microbiota. Recent research has shown that microorganisms belonging to the genus Lactobacillus have probiotic potential. Thus, this study evaluated the potential in vitro probiotic properties of three strains of Lactiplantibacillus plantarum, isolated during the fermentation of high-quality cocoa, against Gardnerella vaginalis and Neisseria gonorrhoeae. Strains were evaluated for their physiological, safety, and antimicrobial characteristics.

Results

The hydrophobicity of L. plantarum strains varied from 26.67 to 91.67%, and their autoaggregation varied from 18.10 to 30.64%. The co-aggregation of L. plantarum strains with G. vaginalis ranged from 14.73 to 16.31%, and from 29.14 to 45.76% with N. gonorrhoeae. All L. plantarum strains could moderately or strongly produce biofilms. L. plantarum strains did not show haemolytic activity and were generally sensitive to the tested antimicrobials. All lactobacillus strains were tolerant to heat and pH resistance tests. All three strains of L. plantarum showed antimicrobial activity against the tested pathogens. The coincubation of L. plantarum strains with pathogens showed that the culture pH remained below 4.5 after 24 h. All cell-free culture supernatants (CFCS) demonstrated activity against the two pathogens tested, and all L. plantarum strains produced hydrogen peroxide. CFCS characterisation in conjunction with gas chromatography revealed that organic acids, especially lactic acid, were responsible for the antimicrobial activity against the pathogens evaluated.

Conclusion

The three strains of L. plantarum presented significant probiotic characteristics against the two pathogens of clinical importance. In vitro screening identified strong probiotic candidates for in vivo studies for the treatment of vaginal infections.

Gardnerella vaginalis and Neisseria gonorrhoeae Are Effectively Inhibited by Lactobacilli with Probiotic Properties Isolated from Brazilian Cupuaçu (Theobroma grandiflorum) Fruit

In recent years, certain Lactobacillus sp. have emerged in health care as an alternative therapy for various diseases. Based on this, this study is aimed at evaluating in vitro the potential probiotics of five lactobacilli strains isolated from pulp of cupuaçu fruit fermentation against Gardnerella vaginalis and Neisseria gonorrhoeae. Our lactobacilli strains were classified as safe for use in humans, and they were tolerant to heat and pH. Our strains were biofilm producers, while hydrophobicity and autoaggregation varied from 13% to 86% and 13% to 25%, respectively. The coaggregation of lactobacilli used in this study with G. vaginalis and N. gonorrhoeae ranged from 15% to 36% and 32% to 52%, respectively. Antimicrobial activity was present in all tested Lactobacillus strains against both pathogens, and the growth of pathogens in coculture was reduced by the presence of our lactobacilli. Also, all tested lactobacilli reduced the pH of the culture, even in incubation with pathogens after 24 hours. The cell-free culture supernatants (CFCS) of all five lactobacilli demonstrated activity against the two pathogens with a halo presence and CFCS characterization assay together with gas chromatography revealed that lactic acid was the most abundant organic acid in the samples (50% to 62%). Our results demonstrated that the organic acid production profile is strain-specific. This study revealed that cupuaçu is a promising source of microorganisms with probiotic properties against genital pathogens. We demonstrated by in vitro tests that our Lactobacillus strains have probiotic properties. However, the absence of in vivo tests is a limitation of our work due to the need to evaluate the interaction of our lactobacilli with pathogens in the vaginal mucosa. We believe that these findings may be useful in developing a product containing our lactobacilli and their supernatants in order to support with vaginal health.

Limosilactobacillus fermentum CECT5716: Mechanisms and Therapeutic Insights

Probiotics microorganisms exert their health-associated activities through some of the following general actions: competitive exclusion, enhancement of intestinal barrier function, production of bacteriocins, improvement of altered microbiota, and modulation of the immune response. Among them, Limosilactobacillus fermentum CECT5716 has become one of the most promising probiotics and it has been described to possess potential beneficial effects on inflammatory processes and immunological alterations. Different studies, preclinical and clinical trials, have evidenced its anti-inflammatory and immunomodulatory properties and elucidated the precise mechanisms of action involved in its beneficial effects. Therefore, the aim of this review is to provide an updated overview of the effect on host health, mechanisms, and future therapeutic approaches.

Antimicrobial activity of Lactobacillus fermentum TcUESC01 against Streptococcus mutans UA159

Dental caries is a multifactorial chronic-infection disease, which starts with a bacterial biofilm formation caused mainly by Streptococcus mutans. The use of probiotics has shown numerous health benefits, including in the fight against oral diseases. Strains of Lactobacillus fermentum have already shown probiotic potential against S. mutans, but there are still few studies. Thus, the aim of our study was to evaluate the antimicrobial activity of the inoculum and metabolites produced by L. fermentum TcUESC01 against S. mutans UA159. For this, a growth curve of L. fermentum was performed and both the inoculum and the metabolites formed in the fermentation were tested against the growth of S. mutans UA159 in agar diffusion tests, and only its metabolites were tested to determine the minimum inhibitory concentration, minimal bactericidal concentration and inhibition of cell adhesion. Inhibition of biofilm formation, pH drop and proton permeability were also tested with the metabolites. The zone of inhibition began to be formed at 14 h and continued until 16 h. The inoculum containing L. fermentum also showed zone of inhibition. The MIC for the metabolites was 1280 mg/mL and the MBC was obtained with a concentration higher than the MIC equal to 5120 mg/mL. Half of the MIC concentration (640 mg/mL) was required to inhibit S. mutans adhesion to the surface of the microplates. In the biofilm analyzes, the treatment with the metabolites in the tested concentration was not able to reduce biomass, insoluble glucans and alkali soluble compared to the control biofilm (p > 0.05). The metabolites also did not affect acid production and acid tolerance of S. mutans cells in biofilms compared to saline group (p > 0.05). Lactic acid (50.38%) was the most abundant organic acid produced by L. fermentum. This is the first report showing that the metabolites produced by the Lactobacillus fermentum TcUESC01 have a potential to be used as an antimicrobial agent against S. mutans, showing anti-adherence and bactericidal activity against planktonic cells of S. mutans. Thus, further studies should be carried out in order to better understand the antimicrobial activity of metabolites of L. fermentum TCUESC01.

Lactobacillus fermentum: a bacterial species with potential for food preservation and biomedical applications

Lactic acid-producing bacteria are the most commonly used probiotics that play an important role in protecting the host against harmful microorganisms, strengthening the host immune system, improving feed digestibility, and reducing metabolic disorders. Lactobacillus fermentum (Lb. fermentum) is a Gram-positive bacterium belonging to Lactobacillus genus, and many reportedly to enhance the immunologic response as well as prevent community-acquired gastrointestinal and upper respiratory infections. Additionally, Lb. fermentum strains produce diverse and potent antimicrobial peptides, which can be applied as food preservative agents or as alternatives to antibiotics. Further functions attributed to probiotic Lb. fermentum strains are their abilities to decrease the level of blood stream cholesterol (as cholesterol-lowering agents) and to potentially help prevent alcoholic liver disease and colorectal cancer among humans. Finally, Lb. fermentum is a key microorganism in sourdough technology, contributing to flavor, texture, or health-promoting dough ingredients, and has recently been used to develop new foods stuffs such as fortified and functional foods with beneficial attributes for human health. Development of such new foodstuffs are currently taking important proportions of the food industry market. Furthermore, an increasing awareness of the consumers prompts the food-makers to implement alternative environmental friendly solutions in the production processes and/or suitable biological alternative to limit the use of antibiotics in feed and food. Here, we give an account on the application of Lb. fermentum strains in the biomedical and food preservation fields, with a focus on probiotic features such as bacteriocin production. We also summarize the use of Lb. fermentum as cell factories with the aim to improve the efficacy and health value of functional food.

Newly isolated lactic acid bacteria from silage targeting biofilms of foodborne pathogens during milk fermentation

Background

Raw milk, meat and plant materials are subjected to high risks of contamination by various pathogenic bacteria and thus their growth prevention is a great challenge in the food industry. Food fermentation by lactic acid bacteria (LAB) besides changing its organoleptic characteristics also helps to eliminate unfavorable microflora and represses growth of pathogens. To the date only few LABs has been reported to exhibit activity against bacteria embedded in the biofilms characterized by extreme resistance to antimicrobials, high exchange rate with resistance genes and represent high risk factor for foodborne disease development.

Results

Six novel LAB strains isolated from the clover silage exhibited pronounced antibacterial activity against biofilm embedded pathogens. We show explicitly that these strains demonstrate high acidification rate, completely repress the growth of E. coli, S. aureus and to a lesser extent P. aeruginosa as well as exhibit appropriate probiotic and milk-fermenting properties. Moreover, in contrast to the approved probiotic strain Lactobacillus plantarum 8PA3, the new isolates were able to efficiently eradicate preformed biofilms of these pathogens and prevent bacterial spreading originating from the biofilm. We suggest these strains as potential additives to the pre-cultures of conventional LAB strains as efficient tools targeting foodborne pathogens in order to prevent food contamination from either seeded raw material or biofilm-fouled equipment.

Conclusions

The AG10 strain identified as L. plantarum demonstrate attractive probiotic and milk fermentation properties as well as high resistance to simulated gastric conditions thus appearing perspective as a starter culture for the prevention of bacterial contamination originating from fouled equipment during milk fermentation.

Lactobacillus fermentum strains of dairy-product origin adhere to mucin and survive digestive juices

Introduction. There is an ever present need to isolate and characterize indigenous bacterial strains with potential probiotic health benefits for humans.Aim. Lactobacillus fermentum of dairy origin was focused because of its propensity to adhere to the intestinal glycoprotein, mucin.Methodology. The lactobacillus strains were screened for mucin adhesion, resistance to low pH and bile, autoaggregation, hydrophobicity, and survival in an in vitro digestion model. The cholesterol-lowering and oxalate-degrading effects of selected strains were also determined. Safety was assessed for haemolytic, mucinolytic and gelatinase activity, biogenic amine production, antibiotic resistance and phenol resistance. Expression of the 32-mmub adhesion-related gene was also measured following strain exposure to simulated gastrointestinal tract (GIT) digestion.Results. The selected mucin-adhesive strains were tolerant to acid (pH 3.0) and bile (0.25 %) and demonstrated >85 % survival following simulated human digestion in the presence of milk. The digestive treatment did not affect the adhesive potential of PL20, and PL27, regardless of the food matrix. The simulated digestion had less effect on their adhesion than on the type strain and it also did not correlate with the mmub gene expression level as determined by qPCR. The selected strains exhibited cholesterol removal (36-44 %) and degraded oxalate (66-55 %). Neither of these strains exhibited undesirable characteristics.Conclusion. These preliminary findings suggest a functionality in the two strains of L. fermentum with high colonization potential on GIT mucosal membranes and possible health-promoting effects. This prima facie evidence suggests the need for further studies to test these probiotic candidates as live biotherapeutic agents in vivo.

Antibiotic Resistance of LACTOBACILLUS Strains

The study provides phenotypic and molecular analyses of the antibiotic resistance in 20 Lactobacillus strains including 11 strains newly isolated from fermented plant material. According to the results of disc diffusion method, 90% of tested lactobacilli demonstrated sensitivity to clindamycin and 95% of strains were susceptible to tetracycline, erythromycin, and rifampicin. Ampicillin and chloramphenicol were found to inhibit all bacteria used in this study. The vast majority of tested strains revealed phenotypic resistance to vancomycin, ciprofloxacin, and aminoglycosides. Most of Lactobacillus strains showed high minimum inhibitory concentrations (MICs) of cefotaxime, ceftriaxone, and cefazolin and therefore were considered resistant to cephalosporins. All the strains exhibited multidrug resistance. The occurrence of resistance genes was associated with phenotypic resistance, with the exception of phenotypically susceptible strains that contained genes for tetracycline (tetK, tetL) and erythromycin (ermB, mefA) resistance. The vanX gene for vancomycin resistance was among the most frequently identified among the lactobacilli (75% of strains), but the occurrence of the parC gene for ciprofloxacin resistance was sporadic (20% of strains). Our results mainly evidence the intrinsic nature of the resistance to aminoglycosides in lactobacilli, though genes for enzymatic modification of streptomycin aadA and aadE were found in 20% of tested strains. The occurrence of extended spectrum beta-lactamases (ESBL) was unknown in Lactobacillus, but our results revealed the blaTEM gene in 80% of strains, whereas blaSHV and blaOXA-1 genes were less frequent (20% and 15% of strains, respectively).

Characterization of Erythromycin and Tetracycline Resistance in Lactobacillus fermentum Strains

Lactobacillus fermentum colonizing gastrointestinal and urogenital tracts of humans and animals is widely used in manufacturing of fermented products and as probiotics. These bacteria may function as vehicles of antibiotic resistance genes, which can be transferred to pathogenic bacteria. Therefore, monitoring and control of transmissible antibiotic resistance determinants in these microorganisms is necessary to approve their safety status. The aim of this study was to characterize erythromycin and tetracycline resistance of L. fermentum isolates and to estimate the potential transfer of resistance genes from lactobacilli to the other Gram-positive and Gram-negative bacteria. Among six L. fermentum strains isolated from human feces and commercial dairy products, five strains demonstrated phenotypic resistance to tetracycline. PCR screening for antibiotic resistance determinants revealed plasmid-located tetracycline resistance genes tet(K) and tet(M) in all strains and erythromycin resistance genes erm(B) in the chromosome of L. fermentum 5-1 and erm(C) in the plasmid of L. fermentum 3-4. All tested lactobacilli lacked conjugative transposon Tn916 and were not able to transfer tetracycline resistance genes to Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Acinetobacter baumannii, Citrobacter freundii, and Escherichia coli by filter mating. Staphylococcus haemolyticus did not accept erythromycin resistance genes from corresponding Lactobacillus strains. Thus, in the present study, L. fermentum was not implicated in the spread of erythromycin and tetracycline resistance, but still these strains pose the threat to the environment and human health because they harbored erythromycin and tetracycline resistance genes in their plasmids and therefore should not be used in foods and probiotics.

In Vitro Activity of Lactobacilli with Probiotic Potential Isolated from Cocoa Fermentation against Gardnerella vaginalis

Study of the probiotic potential of microorganisms isolated from fermented foods has been increasing, especially studies related to lactobacilli. In intestinal models, lactobacilli have demonstrated beneficial properties, such as anti-inflammatory activity and increased antibody production, but the molecular mechanisms involving probiotic and antagonistic action as well as their effect on human vaginal cells have not yet been fully elucidated. The aim of this study was to evaluate the functional and antagonistic properties of three strains of lactobacilli isolated from cocoa fermentation (Lactobacillus fermentum 5.2, L. plantarum 6.2, and L. plantarum 7.1) against Gardnerella vaginalis. Our results show that the lactobacilli have potential use as probiotics, since they have high hydrophobicity and autoaggregation properties and effectively adhere to vaginal cells. Metabolites secreted into the culture medium and whole cells of the strains under study are capable of interfering with the growth of G. vaginalis to different degrees. The elucidation of the antagonistic mechanisms as well as their effect on human cells may be useful in the development of a product containing such microorganisms or products secreted by them.