Leuconostoc species are regarded as important causes for many infections in immunocompromised patients. In this study, we assessed the characteristics of Leuconostoc spp. causing bacteremia in patients at our center. This observational analysis was conducted in the microbiology laboratory of a tertiary care center in northern India from July 2021 to July 2023. Patients in whom blood culture bottles were positive for Leuconostoc lactis were included in the study. Culture isolates were identified by MALDI-ToF MS as L. lactis and tested for antibiotic sensitivity results by Kirby-Bauer disk diffusion method. Demographic and clinical details were collected and analyzed. During the study period, 6,742 blood culture bottles flagged positive. Among these, L. lactis was isolated from 14 (0.21%) patients. The median patient age was 34 years. The male-to-female ratio was 2.5:1. All the patients with L. lactis bacteremia had an underlying condition leading to immunosuppression (e.g., carcinoma and chronic kidney disease). All the patients with L. lactis bacteremia had an intravascular device present at the time of bacteremia. All isolates in the study were sensitive to doxycycline, high level gentamicin, minocycline, ampicillin-sulbactam, and linezolid. Mortality was attributed to bacteremia by L. lactis in five patients. Appropriate and timely identification of the Leuconostoc species is important for the clinician to tailor regimens for the patients.

The human gut microbiome plays a crucial role in skeletal homeostasis. The synbiotic consortium or Defined Microbial Assemblage™ (DMA™) food product, SBD111, consisting of probiotic microbes and prebiotic fibers was designed to promote bone health based on its capacity to produce short chain fatty acids (SCFA), the presence of genes for vitamin K2 production, and its ability to degrade plant fibers. A 28-day repeated administration study was performed to evaluate the oral toxicity of SBD111 in female rats (age/weight at study start: 5-7 weeks/120-180 g) administered levels of 0, 2.0 x 1010, 9.8 x 1010, or 2.0 x 1011 colony forming units (CFU)/kg-bw. No mortality or morbidity occurred during the study. There were no significant differences in body weights, hematology, serum chemistry, coagulation, organ weights, or food consumption in the test groups compared to the controls. Liver weight to body weight ratios were signficantly decreased at 9.8 x 1010 CFU/kg-bw when compared to controls. No treatment related changes in motor activity, sensory stimuli, or grip strength were observed. Based on these findings, SBD111 administered to female rats has a no-observable adverse effect level (NOAEL) at the highest level tested of 2.0 x 1011 CFU/kg-bw.

Micro-inflammation in the gut, assessed by fecal calprotectin (FC), is considered a component of the pathogenesis of functional diarrhea (FD). Since probiotics may suppress micro-inflammation in the intestine by competing with harmful bacteria, we hypothesized that they would reduce the ratio of loose stool symptoms and gut inflammation in patients with FD. We conducted a double-blind, placebo-controlled trial to assess the clinical and laboratory effects of Lactobacillus plantarum CJLP243 in FD patients with elevated FC levels for two months. Twenty-four patients diagnosed with FD with elevated FC levels were randomly assigned to either a probiotic group or a placebo group. After 2 months, 10 patients in the probiotic group and 12 patients in the placebo group completed the study, and FD symptoms, FC values, and intestinal flora were re-evaluated in these subjects. The percentage of subjects who had adequate FD relief (decrease in loose stool frequency) in the probiotic group was significantly increased after two months compared with the baseline. In addition, the probiotic group showed a statistically significant decrease in log-transformed FC values compared with the pre-treatment group, whereas the placebo group showed no difference before and after the intervention. Furthermore, the levels of Leuconostoc genus organisms in the gut microbiota composition in the probiotic group increased significantly after the end of the study compared with the baseline values. In this preliminary exploratory research, we found that two months of Lactiplantibacillus plantarum CJLP243 treatment resulted in FD symptom improvement, reduced FC values, and increased Leuconostoc levels, suggesting that the intake of Lactiplantibacillus plantarum was helpful in those patients. These findings need to be validated via further clinical studies.

Kefir is a well-known health-promoting beverage that can be produced by using kefir grains (traditional method) or by using natural starter cultures from kefir (backslopping method). The aim of this study was to elucidate the microbial dynamics and volatilome profile occurring during kefir production through traditional and backslopping methods by using five kefir grains that were collected in Bosnia and Herzegovina. The results from conventional pour plating techniques and amplicon-based sequencing were combined. The kefir drinks have also been characterized in terms of their physico-chemical and colorimetric parameters. A bacterial shift from Lactobacillus kefiranofaciens to Acetobacter syzygii, Lactococcus lactis and Leuconostoc pseudomesenteroides from kefir grains in traditional kefir to backslopped kefir was generally observed. Despite some differences within samples, the dominant mycobiota of backslopped kefir samples remained quite similar to that of the kefir grain samples. However, unlike the lactic acid and acetic acid bacteria, the yeast counts decreased progressively from the grains to the backslopped kefir. The backslopped kefir samples showed higher protein, lactose and ash content and lower ethanol content compared to traditional kefir samples, coupled with optimal pH values that contribute to a pleasant sensory profile. Concerning the volatilome, backslopped kefir samples were correlated with cheesy, buttery, floral and fermented odors, whereas the traditional kefir samples were correlated with alcoholic, fruity, fatty and acid odors. Overall, the data obtained in the present study provided evidence that different kefir production methods (traditional vs backslopping) affect the quality characteristics of the final product. Hence, the functional traits of backslopped kefir should be further investigated in order to verify the suitability of a potential scale-up methodology for backslopping.

Glycosyltransferase-producing Leuconostoc lactis CCK940 produces CCK- oligosaccharides, gluco-oligosaccharide molecules, using sucrose and maltose as donor and acceptor molecules, respectively. In this study, the immunostimulatory activities of CCK-oligosaccharides on RAW264.7 macrophages and BALB/c mice were evaluated. CCK-oligosaccharides induced the expression of phosphorylated-p38, extracellular-signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) and upregulation of phagocytic activity in RAW264.7 macrophages, suggesting their involvement in mitogen-activated protein kinase (MAPK) signaling pathway and phagocytosis. When CCK-oligosaccharides were administered to mice intraperitoneally injected with cyclophosphamide (CY), spleen indices and expressions of interleukin (IL)-6, IL-10, and tumor necrosis factor-α increased, compared with those in only CY-treated group. These findings suggest that CCK-oligosaccharides can be used as an effective immunostimulating agent.

OBJECTIVE: Probiotic supplementation demonstrates beneficial effects on serum lipid profiles. We hypothesized that probiotics could benefit patients presenting with alopecia, secondary to improved blood flow to the scalp.
METHODS: Our study included men with stage II to V patterns of hair loss based on the Hamilton-Norwood classification and women with stage I to III patterns of hair loss based on the Ludwig classification. All patients were administered 80 mL of Mogut® (a kimchi and cheonggukjang probiotic product) twice a day. Hair growth and numbers were measured using the Triple Scope System® (KC Technology, Korea) at baseline and after 1 and 4 months of administration of a kimchi and cheonggukjang probiotic product.
RESULTS: At baseline, the mean hair count was 85.98±20.54 hairs/cm² and the mean thickness was 0.062±0.011 mm in all patients (n=46). Hair count and thickness had significantly increased at 1 month (90.28±16.13 hairs/cm² and 0.068±0.008 mm, respectively) and at 4 months (91.54±16.29 hairs/cm² and 0.066±0.009 mm, respectively). In this study, we found that a kimchi and cheonggukjang probiotic product could promote hair growth and reverse hair loss without associated adverse effects such as diarrhea.
CONCLUSIONS: We suggest that the observed improvements in hair count and thickness resulted from initiation of the anagen phase in hair follicles in response to probiotics.

OBJECTIVE: Head injury (HI) induces a hypercatabolic state, dysimmunity, and septic complications that increase morbidity and mortality. Although compromised immune function is usually incriminated in infection occurrence, gut dysbiosis could also be involved in this phenomenon and, to our knowledge, has never been considered. To assess if HI could affect microbiota, we explored the impact of HI on intestinal microbiota in a rodent model of fluid percussion.
METHODS: Nineteen rats were randomly assigned to two groups: Healthy rats fed ad libitum (n = 7) and HI rats (n = 12), which received standard enteral nutrition for 4 d. Four days after HI, rats were euthanized and cecal contents were sampled. Cecal microbiota was assessed using real-time quantitative polymerase chain reaction.
RESULTS: HI significantly decreased the cecal content of strict anaerobic groups, Bacteroides/Prevotella group (HI 8.9 versus healthy controls 9.3 median log10 colony forming units [CFU]/g, P = 0.007), Clostridium cluster XIVab (HI 7.9 versus healthy controls 8.9 median log10 CFU/g, P = 0.002), Lactobacillus/Leuconostoc group (HI 8.5 versus healthy controls 9.4 median log10 CFU/g, P = 0.044), and Bifidobacterium sp. (HI 3.0 versus healthy controls 8.2 median log10 CFU/g, P < 0.001). In contrast, colonization by Escherichia coli was dramatically increased (HI 10.5 versus healthy controls 7.0 median log10 CFU/g, P < 0.001).
CONCLUSIONS: HI profoundly modified the gut microbiota homeostasis and thus could contribute to infection in head trauma patients. These preliminary results open a new field of research in the management of patients with HI.

Despite being potentially highly useful for characterizing the biodiversity of phages, metagenomic studies are currently not available for dairy bacteriophages, partly due to the lack of a standard procedure for phage extraction. We optimized an extraction method that allows the removal of the bulk protein from whey and milk samples with losses of less than 50% of spiked phages. The protocol was applied to extract phages from whey in order to test the notion that members of Lactococcus lactis 936 (now Sk1virus), P335, c2 (now C2virus) and Leuconostoc phage groups are the most frequently encountered in the dairy environment. The relative abundance and diversity of phages in eight and four whey mixtures from dairies using undefined mesophilic mixed-strain cultures containing Lactococcus lactis subsp. lactis biovar diacetylactis and Leuconostoc species (i.e., DL starter cultures) and defined cultures, respectively, were assessed. Results obtained from transmission electron microscopy and high-throughput sequence analyses revealed the dominance of Lc. lactis 936 phages (order Caudovirales, family Siphoviridae) in dairies using undefined DL starter cultures and Lc. lactis c2 phages (order Caudovirales, family Siphoviridae) in dairies using defined cultures. The 936 and Leuconostoc phages demonstrated limited diversity. Possible coinduction of temperate P335 prophages and satellite phages in one of the whey mixtures was also observed.IMPORTANCE The method optimized in this study could provide an important basis for understanding the dynamics of the phage community (abundance, development, diversity, evolution, etc.) in dairies with different sizes, locations, and production strategies. It may also enable the discovery of previously unknown phages, which is crucial for the development of rapid molecular biology-based methods for phage burden surveillance systems. The dominance of only a few phage groups in the dairy environment signifies the depth of knowledge gained over the past decades, which served as the basis for designing current phage control strategies. The presence of a correlation between phages and the type of starter cultures being used in dairies might help to improve the selection and/or design of suitable, custom, and cost-efficient phage control strategies.

The aim of our study was to demonstrate higher concentrations of lactic acid bacteria (LAB) on the colonic mucosa in operated colorectal cancer patients treated with oral intake of synbiotics or prebiotics preoperatively. We also tried to prove that the systemic inflammatory response after surgery is not so severe in patients who took synbiotics or prebiotics, furthermore these patients have less postoperative complications and a favorable postoperative course. 73 patients with preceding colorectal operations were recruited. They were randomized into three groups. One group received preoperatively prebiotics, the second synbiotics in and third was preoperatively cleansed. We have defined the number of four different probiotic bacteria on colonic mucosa with polymerase chain reaction (PCR). Serum levels of interleukin-6, CRP, fibrinogen, white cell count and differential blood count were measured pre- and postoperatively to determine systemic inflammatory response. We succeed in confirming that in the synbiotic group there were considerably more LAB presented on the mucosa. They did pass the upper gastrointestinal tract and were isolated in colonic mucosa. On the other hand, we did not find any statistical differences in systemic inflammatory response measured by upper factors and no differences in postoperative course and complications rate between all three groups.

Isothermal titration calorimetry (ITC) is a label-free technique that allows the direct determination of the heat absorbed or released in a reaction. Frequently used to determining binding parameters in biomolecular interactions, it is very useful to address enzyme-catalyzed reactions as both kinetic and thermodynamic parameters can be obtained. Since calorimetry measures the total heat effects of a reaction, it is important to consider the contribution of the heat of protonation/deprotonation that is possibly taking place. Here, we show a case study of the reaction catalyzed by the glucose-6-phosphate dehydrogenase (G6PD) from Leuconostoc mesenteroides. This enzyme is able to use either NAD(+) or NADP(+) as a cofactor. The reactions were done in five buffers of different enthalpy of protonation. Depending on the buffer used, the observed calorimetric enthalpy (ΔH(cal)) of the reaction varied from -22.93 kJ/mol (Tris) to 19.37 kJ/mol (phosphate) for the NADP(+)-linked reaction, and -11.67 kJ/mol (Tris) to 7.32 kcal/mol or 30.63 kJ/mol (phosphate) for the NAD(+) reaction. We will use this system as an example of how to extract proton-independent reaction enthalpies from kinetic data to ensure that the reported accurately represent the intrinsic heat of reaction.