Rod-shaped Lactic Acid Bacteria Research Articles

Identification and Characterization of Human Breast Milk and Infant Fecal Cultivable Lactobacilli Isolated in Bulgaria: A Pilot Study.

During the last few decades, the main focus of numerous studies has been on the human breast milk microbiota and its influence on the infant intestinal microbiota and overall health. The presence of lactic acid bacteria in breast milk affects both the quantitative and qualitative composition of the infant gut microbiota. The aim of this study was to assess the most frequently detected cultivable rod-shaped lactobacilli, specific for breast milk of healthy Bulgarian women and fecal samples of their infants over the first month of life, in 14 mother-infant tandem pairs. Additionally, we evaluated the strain diversity among the most common isolated species. A total of 68 Gram-positive and catalase-negative strains were subjected to identification using the MALDI-TOF technique. Predominant cultivable populations belonging to the rod-shaped lactic acid bacteria have been identified as Lacticaseibacillus rhamnosus, Limosilactobacillus fermentum, Lacticaseibacillus paracasei, and Limosilactobacillus reuteri. Also, we confirmed the presence of Lactiplantibacillus plantarum and Lactobacillus gasseri. Up to 26 isolates were selected as representatives and analyzed by 16S rRNA sequencing for strain identity confirmation and a phylogenetic tree based on 16S rRNA gene sequence was constructed. Comparative analysis by four RAPD primers revealed genetic differences between newly isolated predominant L. rhamnosus strains. This pilot study provides data for the current first report concerning the investigation of the characteristic cultivable lactobacilli isolated from human breast milk and infant feces in Bulgaria.

The community of lactic acid bacteria during kimoto-style seed mash making process and its control.

Kimoto-style seed mash making processes such as the kimoto and yamahai-moto processes are driven by various microorganisms, and it is very important to make lactic acid bacteria grow stably for the brewing of a sake product with consistent quality. A model of bacterial transition from spherical lactic acid bacteria to rod-shaped lactic acid bacteria during kimoto-making has been advocated, but the model cannot explain all cases of a transition of a bacterial community during kimoto-making at various breweries. Several studies have described unique bacterial transition patterns that differ from those considered in the proposed model, and it is possible that factors such as differences in the initial bacterial community among breweries may cause the diversity of bacterial transitions. In this minireview, I summarize the research concerning the community of lactic acid bacteria during the kimoto-style seed mash making process, and I discuss how stable lactic acid fermentation can be achieved.

Bacteraemia caused by Lactobacillus casei in a patient after cardiac surgery. A case report

BackgroundBacteria of the Lactobacillus family are a part of the physiological flora of the oral cavity, gastrointestinal tract, and urinary tract. We have used them in the food industry as probiotics and supplements. In some settings, rod-shaped lactic acid bacteria may become pathogenic. It may occur in immunocompromised or heart disease patients after cardiac surgery, patients with disturbed intestinal wall permeability, or those treated with broad-spectrum antibiotics.Case presentationWe present rare bacteraemia induced by the probiotic bacterium Lactobacillus casei in a 63-year-old patient after the attempted removal of ICD electrodes, complicated by acute regurgitation of the tricuspid valve. The patient underwent urgent cardiac surgery, the electrode elements were removed, and the tricuspid valve was replaced with a biological prosthesis. After surgery, the patient required intensive, multidisciplinary treatment with mechanical ventilation, continuous renal replacement therapy, broad-spectrum empirical antibiotic therapy, parenteral nutrition, and blood product transfusion because of multiple organ failure. On the 14th day of hospitalisation, the clinical symptoms of septic shock were observed. The microbiological investigation was performed, and Lactobacillus casei was cultured from a dialysis catheter sample. Dedicated antimicrobials were administered, and the patient was discharged home in good overall condition.ConclusionsThe present case shows that the promoted use of probiotics must be cautiously administered to patients in severe conditions, especially when accompanied by reduced immune system efficiency symptoms.

Selenium bio-enrichment of Mediterranean fruit juices through lactic acid fermentation

This work was carried out to elaborate selenium (Se) bio-enriched fermented Mediterranean fruit juices. To this purpose, pomegranate and table red grape juices were added with sodium selenite (Na2SeO3) and fermented by Levilactobacillus brevis CRL 2051 and Fructobacillus tropaeoli CRL 2034 individually or combined. To better evaluate the effect of selenite addition and starter strain inoculums on the total bacterial community of the fruit juices, fermentation trials were performed with raw and pasteurized fruit juices. No statistical significant differences were observed for total mesophilic microorganisms (TMM) and rod-shaped lactic acid bacteria (LAB) levels among raw and pasteurized juices inoculated with the starter strains, while significant differences between those juices with and without selenite were registered. LAB cocci, Pseudomonadaceae and yeasts were detected only for the raw juice preparations. The dominance of L. brevis CRL 2051 and F. tropaeoli CRL 2034 was confirmed by randomly amplified polymorphic DNA (RAPD)-PCR analysis. After fermentation, pH dropped for all inoculated trials and control raw juices. The soluble solid content (SSC) levels of the raw juices were higher than the corresponding pasteurized trials. The thermal treatment affected consistently yellowness of grape juice trials and redness of pomegranate juices. No microbial Se accumulation was registered for pomegranate juices, while F. tropaeoli CRL 2034 accumulated the highest amount of Se (65.5 μg/L) in the grape juice. For this reason, only trials carried out with raw grape juices were investigated by metagenomics analysis by Illumina MiSeq technology. Non-inoculated grape juices were massively fermented by acetic acid bacteria while Fructobacillus and Lactobacillus (previous genus name of Levilactobacillus) represented the highest operational taxonomy units (OTUs) relative abundance % of the trials inoculated with the starter strains as confirmed by this technique.

Low-temperature centrifugation of milk for manufacture of raw milk cheeses: Impact on milk debacterization and cheese yield

Centrifugation is occasionally applied to clean cheese milk, particularly to remove Clostridia's spores that may cause the “late blowing” of cheese. The sludge separated by centrifugation also contains fat and protein, thus is sterilized and added back to cheese milk. In manufacture of raw milk cheeses, centrifugation shall be performed at temperature below 40 °C and no sterilized sludge can be added to vat milk. Both these limitations negatively affect cheese yield. To evaluate process sustainability, three different centrifugation configurations were tested at a factory producing a traditional raw-milk extra-hard cheese. Either a single or double centrifugation, the latter with two different volumes of discharged sludge, were tested over 3-week periods each. Efficiency of spore removal, decrease of total bacterial count, loss of milk solids and cheese yield were evaluated daily with respect to not-centrifuged milk from the same batch. Double centrifugation with low-volume sludge gave highest efficiency of spore removal, i.e. 98.2%, while the single process minimized the loss of cheese yield. Impedometric analysis indicated that centrifugation caused a preferential removal of rod-shaped lactic acid bacteria, regardless of configuration. This finding was confirmed by microscopy and suggested that a different bacteria population would operate during cheese ripening.

Companilactobacillus pabuli sp. nov., a lactic acid bacterium isolated from animal feed.

A Gram-positive, facultative anaerobic, catalase-negative, non-motile, non-spore-forming and rod-shaped lactic acid bacterium strain, denoted as NFFJ11T and isolated from total mixed fermentation feed in the Republic of Korea, was characterized through polyphasic approaches, including sequence analyses of the 16S rRNA gene and housekeeping genes (rpoA and pheS), determination of average nucleotide identity and in silico DNA-DNA hybridization, fatty acid methyl ester analysis, and phenotypic characterization. Phylogenetic analyses based on 16S rRNA, rpoA and pheS gene sequences revealed that strain NFFJ11T belonged to the genus Companilactobacillus. The 16S rRNA gene sequence of strain NFFJ11T exhibited high similarity to Companilactobacillus formosensis S215T (99.66 %), Companilactobacillus farciminis Rv4 naT (99.53 %), Companilactobacillus crustorum LMG 23699T (99.19 %), Companilactobacillus futsaii YM 0097T (99.06 %), Companilactobacillus zhachilii HBUAS52074T (98.86 %) and Companilactobacillus heilongiiangensis S4-3T (98.66 %). However, average nucleotide identity and in silico DNA-DNA hybridization values for these type strains were in the range of 79.90-92.93 % and 23.80-49.30 %, respectively, which offer evidence that strain NFFJ11T belongs to a novel species of the genus Companilactobacillus. The cell-wall peptidoglycan type was A4α (l-Lys-d-Asp) and the G+C content of the genomic DNA was 35.7 mol%. The main fatty acids of strain NFFJ11T were C18 : 1 ω9c (43.3 %), C16 : 0 (20.1 %) and summed feature 7 (18.3 %; comprising any combination of C19 : 1 ω7c, C19 : 1 ω6c and C19 : 0 cyclo ω10c). Through polyphasic taxonomic analysis, it was observed that strain NFFJ11T represents a novel species belonging to the genus Companilactobacillus, for which the name Companilactobacillus pabuli sp. nov. is proposed. The type strain is NFFJ11T (= KACC 21771T= JCM 34088T).

Dominant Lactic Acid Bacteria in Naturally Fermented Milks from Messinese Goat’s Breed

Background: Lactic Acid Bacteria (LAB) are an important group of microorganisms responsible for the fermentation dairy products. This study was done to identify the dominant lactic acid bacteria in naturally fermented milks from Messinese goat’s breed. Methods: Eighteen individual raw milk samples collected from Messinese goat’s breed were acidified at pH 5.20 and left to spontaneously ferment at 37 °C for 4 days. All samples were analyzed for rod- and coccus-shaped LAB. Also, all presumptive LAB were isolated and differentiated according to their phenotypic properties and genetic polymorphisms and then identified by sequencing the 16S rRNA gene. Data were statistically analyzed using SAS 9.2 software. Results: Levels of coccus- and rod-shaped LAB were in the range of 1.78-7.10 log and 1.00-7.09 log colony forming unit/ml, respectively. The microbiological counts on the two different growth media were significantly (p<0.05) different among the samples. Among 12 identified strains, the most numerous one was Enterococcus hirae (n=4), followed by E. faecium (n=3), while the other species (E. durans, E. faecalis, E. lactis, Lactococcus lactis, and Leuconostoc lactis) included one strain each. Conclusion: The major group identified in this study was mainly represented by members of Enterococcus genus. Although Enterococcus spp. are related to the typicality of some traditional fermented dairy products, this study highlights the need for risk assessment of pathogenic enterococci species for the consumers.

Lactobacillus porci sp. nov., isolated from small intestine of a swine.

A facultatively anaerobic, Gram-stain-positive, catalase-negative, rod-shaped lactic acid bacterium, designated SG816T, was isolated from small intestine of a swine. Optimal growth occurred at 37 °C and pH 7.0. Furthermore, growth occurred in NaCl up to 0.5 % (w/v) but not at levels of salinity higher than 1 %. Comparative 16S rRNA gene sequencing and the matrix-associated laser desorption/ionization-time-of-flight mass spectometry profiling showed that strain SG816T was closely related to Lactobacillus delbrueckiisubsp. bulgaricus KCTC 3635T (95.9 %) and Lactobacillus delbrueckiisubsp. indicus JCM 15610T (95.9 %), followed by other Lactobacillus delbrueckii subspecies (95.9-95.7 %) and Lactobacillus equicursoris DSM 19284T (95.6 %). A comparison of two housekeeping genes, RNA polymerase alpha subunit (rpoA) and phenylalanyl-tRNA synthase alpha subunit (pheS), revealed that strain SG816T formed a separate branch within the clade of the genus Lactobacillus. The DNA G+C content level of the strain SG816T was 51.5 mol%. The strain was homofermentative and produced d-lactic acid from glucose fermentation. The major cellular fatty acids (>10 %) of the isolate were C18 : 1ω9c and C16 : 0. The peptidoglycan type was A4α l-Lys-d-Asp. On the basis of distinct phenotypic and phylogenetic properties, strain SG816T represents a novel species of the genus Lactobacillus, for which the name Lactobacillus porci sp. nov. is proposed. The type strain is SG816T (=KCTC 21090T=NBRC 112917T).

Lactobacillus formosensis sp. nov., a lactic acid bacterium isolated from fermented soybean meal.

A Gram-reaction-positive, catalase-negative, facultatively anaerobic, rod-shaped lactic acid bacterium, designated strain S215(T), was isolated from fermented soybean meal. The organism produced d-lactic acid from glucose without gas formation. 16S rRNA gene sequencing results showed that strain S215(T) had 98.74-99.60 % sequence similarity to the type strains of three species of the genus Lactobacillus (Lactobacillus farciminis BCRC 14043(T), Lactobacillus futsaii BCRC 80278(T) and Lactobacillus crustorum JCM 15951(T)). A comparison of two housekeeping genes, rpoA and pheS, revealed that strain S215(T) was well separated from the reference strains of species of the genus Lactobacillus. DNA-DNA hybridization results indicated that strain S215(T) had DNA related to the three type strains of species of the genus Lactobacillus (33-66 % relatedness). The DNA G+C content of strain S215(T) was 36.2 mol%. The cell walls contained peptidoglycan of the d-meso-diaminopimelic acid type and the major fatty acids were C18 : 1ω9c, C16 : 0 and C19 : 0 cyclo ω10c/C19 : 1ω6c. Phenotypic and genotypic features demonstrated that the isolate represents a novel species of the genus Lactobacillus, for which the name Lactobacillus formosensis sp. nov. is proposed. The type strain is S215(T) ( = NBRC 109509(T) = BCRC 80582(T)).

Human milk is a source of lactic acid bacteria for the infant gut

Objectives To investigate whether human breast milk contains potentially probiotic lactic acid bacteria, and therefore, whether it can be considered a synbiotic food. Study design Lactic acid bacteria were isolated from milk, mammary areola, and breast skin of eight healthy mothers and oral swabs and feces of their respective breast-fed infants. Some isolates (178 from each mother and newborn pair) were randomly selected and submitted to randomly amplified polymorphic DNA (RAPD) polymerase chain reaction analysis, and those that displayed identical RAPD patterns were identified by 16S rDNA sequencing. Results Within each mother and newborn pair, some rod-shaped lactic acid bacteria isolated from mammary areola, breast milk, and infant oral swabs and feces displayed identical RAPD profiles. All of them, independently from the mother and child pair, were identified as Lactobacillus gasseri. Similarly, among coccoid lactic acid bacteria from these different sources, some shared an identical RAPD pattern and were identified as Enterococcus faecium. In contrast, none of the lactic acid bacteria isolated from breast skin shared RAPD profiles with lactic acid bacteria of the other sources. Conclusions Breast-feeding can be a significant source of lactic acid bacteria to the infant gut. Lactic acid bacteria present in milk may have an endogenous origin and may not be the result of contamination from the surrounding breast skin.

Lactic acid bacteria isolated from soy sauce mash in Thailand.

Fourteen sphere-shaped and 30 rod-shaped lactic acid bacteria were isolated from soy sauce mash of two factories in Thailand. These strains were separated into two groups, Group A and Group B, by cell shape and DNA-DNA similarity. Group A contained 14 tetrad-forming strains, and these strains were identified as Tetragenococcus halophilus by DNA similarity. Group B contained 30 rod-shaped bacteria, and they were further divided into four Subgroups, B1, B2, B3, and B4, and three ungrouped strains by phenotypic characteristics and DNA similarity. Subgroup B1 contained 16 strains, and these strains were identified as Lactobacillus acidipiscis by DNA similarity. Subgroup B2 included two strains, and the strains were identified as Lactobacillus farciminis by DNA similarity. Subgroup B3 contained five strains. The strains had meso-diaminopimelic acid in the cell wall, and were identified as Lactobacillus pentosus by DNA similarity. The strains tested produced DL-lactic acid from D-glucose. Subgroup B4 contained four strains. The strains had meso-diaminopimelic acid in the cell wall, and they were identified as Lactobacillus plantarum by DNA similarity. Two ungrouped strains were homofermentative, and one was heterofermentative. They showed a low degree of DNA similarity with the type strains tested, and were left unnamed. The distribution of lactic acid bacteria in soy sauce mash in Thailand is discussed.

Description of Paralactobacillus selangorensis gen. nov., sp. nov., a new lactic acid bacterium isolated from chili bo, a Malaysian food ingredient.

Paralactobacillus selangorensis gen. nov., sp. nov. is described. This organism, isolated from a Malaysian food ingredient called chili bo, is an obligatory homofermentative, rod-shaped lactic acid bacterium. The G+C content is 46.1-46.2+/-0.3 mol%. Earlier 16S rRNA studies showed that this organism constitutes a new taxon distantly related to the Lactobacillus casei-Pediococcus group. A phenotypic description that distinguishes Paralactobacillus selangorensis from other genera of lactic acid bacteria is presented. The type strain of Paralactobacillus selangorensis is LMG 17710T.

An introduction to rod-shaped lactic-acid bacteria

The genus Lactobacillus is mainly found in the intestinal tract of healthy humans and animals as well as in fermenting vegetables or plant materials, such as silage. It has a moderate diffusion in meat products and is rarely found in wines and beers. On the other hand, rod-shaped lactic-acid bacteria are largely used in the preparation of a variety of foods and feed products. As starter cultures, they are omnipresent in cheeses and dairy manufacturing. Specific fermentation processes have been developed in order to encourage the growth of the desired species, some of which are fastidious organisms such as L. delbrueckii ssp. bulgaricus, L. helveticus and L. sanfrancisco. In addition, a promising and interesting perspective is the use of rod-shaped lactic-acid bacteria, primarily L. acidophilus, L. reuteri and L. salivarius as probiotic starters to preserve the natural biological equilibrium of the intestinal tract.

Lactobacillus kefiranofaciens sp. nov. Isolated from Kefir Grains

Lactobacillus kefiranofaciens sp. nov. is described. Four strains of this species isolated from kefir grains are slime-forming, homofermentative, rod-shaped lactic acid bacteria. They differ from all the validly described homofermentative species of the genus Lactobacillus in their carbohydrate fermentation pattern. Their guanine-plus-cytosine content of deoxyribonucleic acid is 34 to 35 mol%. Deoxyribonucleic acids obtained from six other Lactobacillus species do not show significant relatedness to a representative strain of the new species. The type strain of L. kefiranofaciens sp. nov. is WT-2B (ATCC 43761).

Lactobacillus acetotolerans, a New Species from Fermented Vinegar Broth

Thirteen strains of rod-shaped lactic acid bacteria, resistant to high concentrations of acetic acid, were isolated from the fermented broth of rice vinegar. These isolates showed homofermentation and differed from all the validly described homofermentative species of the genus Lactobacillus. Although the isolates were divided into two groups on the basis of acid production pattern from carbohydrates and nutritional requirements for growth, all showed extremely high deoxyribonucleic acid homology. The isolates were considered to represent a new species of the genus Lactobacillus. The two groups, based on their biochemical and physiological properties, were treated as biovar I and biovar II. A new species proposed for these isolates was named Lactobacillus acetotolerans. The type strain of L. acetotolerans sp. nov. is NBI3014 (=JCM 3825).

Taxonomy of Lactobacilli Isolated from the Alimentary Tract of Chickens

One hundred and seventy six strains of rod-shaped lactic acid bacteria, 144 homofermentative and 32 heterofermentative, were isolated from different sections of the digestive tracts of 30 chickens. Chemotaxonomic and genetic characteristics revealed that homofermentative strains isolated from crops, belong to Lactobacillus salivarius whereas homofermentative strains from the intestinal tract can be allocated to the different groups of L. acidophilus and to L. salivarius . Of the 32 heterofermentative strains, 30 were assigned to L. reuteri .

Lactobacillus kefir sp.nov., a component of the microflora of Kefir

About 100 strains of heterofermentative rod-shaped lactic acid bacteria have been isolated from kefir grains and drink kefir, respectively. These isolates differ from Lactobacillus brevis and the other species of heterofermentative lactobacilli so far validly published with respect to biochemical characteristics and DNA/DNA homology. They are thus considered as representatives of the new species Lactobacillus kefir sp. nov., with strain DSM 20587 (= A/K) being the type strain.

On the incidental occurrence of rod-shaped, dextran producing bacteria in a beet-sugar factory

From a „Froschlaich” formed in a sugar-factory, the responsible organism was isolated. This organism could be identified with the dextran-forming, heterofermentative, rod-shaped lactic acid bacterium,Betabacterium vermiforme, a bacterium first described byWard as one of the constituents of the „ginger-beer plant” and recently recognized byMayer (18) as being also one of the components of the „tibi”-consortium. Thus it has been shown that the formation of the „Froschlaich” in sugar factories is not always due toLeuconostoc mesenterioides or toBacillus vulgatus, but can also be caused byBetabacterium vermiforme.