Weissella Confusa Research Articles

Identification of Predominant Lactic Acid Bacteria Associated with Kunun-Zaki and Kindirmo a Traditional Fermented Food of Nigeria

Human intestinal flora is very diverse; with lactic acid bacteria (LAB) existing as part of the most vital gut microbes that improve host health. The application of LAB as a whole organism or its metabolite in the case of probiotic and bacteriocin respectively is extensive. Thus, the need to always bio-prospect for newer strains of LAB is essential. This study focused on isolating LAB from kunun-zaki and kindirmo, a fermented non-alcoholic beverage of non-dairy and dairy sources respectively, explored their physiological and biochemical properties, antibiotics sensitivity pattern and identified based on their 16S rRNA sequencing. A total of eighty isolates were selected sixty-six from kunun-zaki and fourteen from kindirmo in which 93.7% were bacilli and 6.3% were spherical in shape having 68.75% and 30% homofermentative and heterofermentative pathway respectively. All isolates have the ability to utilize glucose to produce lactic acid while their tolerance to pH 3 and salt concentration at 2%, 4% and 6.5% varied widely. Thirty-four isolates based on their physiological and biochemical properties were selected for molecular identification to ascertain their genera and species. Limosilactobacillus fermentum (68%); Lactiplantibacillus plantarum (6%) and Weissella confusa (3%) were confirmed species isolated. Thus, it was concluded that traditional fermented foods such as kunun-zaki and kindirmo are a good source to bio-prospect for LAB for product development, starter culture and probiotic study.

Functional characterization of α-Gal producing lactic acid bacteria with potential probiotic properties.

The possibility of exploiting the human immune response to glycan α-Gal for the control of multiple infectious diseases has been the objective of recent investigations. In this field of research, the strain of Escherichia coli O86:B7 has been at the forefront, but this Gram-negative microorganism presents a safety concern and therefore cannot be considered as a probiotic. To address this challenge, this study explored the identification of novel lactic acid bacteria with a safe history of use, producing α-Gal and having probiotic potential. The lactic acid bacteria were isolated from different traditionally fermented foods (kununn-zaki, kindirmo, and pulque) and were screened for the production of α-Gal and some specific probiotic potential indicators. The results showed that Ten (10) out of forty (40) [25%] of the tested lactic acid bacteria (LAB) produced α-Gal and were identified as Limosilactobacillus fermentum, Levilactobacillus brevis, Agrilactobacillus composti, Lacticaseibacillus paracasei, Leuconostoc mesenteroides and Weissella confusa. Four (4) LAB strains with highest levels of α-Gal were further selected for in vivo study using a mouse model (α1,3GT KO mice) to elucidate the immunological response to α-Gal. The level of anti-α-Gal IgG observed were not significant while the level of anti-α-Gal IgM was lower in comparison to the level elicited by E. coli O86:B7. We concluded that the lactic acid bacteria in this study producing α-Gal have potential probiotic capacity and can be further explored in α-Gal-focused research for both the prevention and treatment of various infectious diseases and probiotic development.

Efficient secretion of xylanase in Escherichia coli for production of prebiotic xylooligosaccharides

The N-terminal 20 amino acid of Lactobacillus amylovorus feruloyl esterase (N20) was used as a signal peptide for fusion expression with a novel xylanase Xyl derived from Bacillus paralicheniformis. Results showed that N20-Xyl could be effectively secreted out of E. coli BL21(DE3) cells. Enzymatic characterization indicated that Xyl and N20-Xyl exhibited similar properties with the optimal pH of 8.0 and temperature of 50 °C. Furthermore, xylooligosaccharides were prepared through simultaneous xylanase secretion and xylan degradation by using E. coli. The final extracellular reducing sugar content reached 8.79 ± 0.10 g/L based on 40 g/L xylan, and the main products were xylobiose, xylotriose, and xylotetraose. Moreover, it was found that Levilactobacillus brevis 217-168, Enterococcus faecium 217-169, Pediococcus acidilactici 217-112, and Weissella confusa 217-162 could efficiently utilize these xylooligosaccharides for growth. Therefore, this study provided a method for the production of prebiotic xylooligosaccharides via simultaneous fermentation by using E. coli.

Isolation and Characterization of a Cholesterol-Lowering Bacteria from Bubalus bubalis Raw Milk

Probiotics retrieved from animal sources have substantial health benefits for both humans and animals. The present study was designed to identify lactic acid bacteria (LAB) isolated from domestic water buffalo milk (Bubalus bubalis) and to evaluate their potential as target-based probiotics. Forty-six LAB strains were isolated and, among them, five strains (NMCC-M2, NMCC-M4, NMCC-M5, NMCC-M6, and NMCC-M7) were regarded as possible probiotics on the basis of their phenotypic and biochemical properties. These isolates were molecularly identified as Weissella confusa (NMCC-M2), Leuconostoc pseudo-mesenteroides (NMCC-M4), Lactococcus lactis Subsp. hordniae (NMCC-M5), Enterococcus faecium NMCC-M6, and Enterococcus lactis NMCC-M7. The tested bacterial strains showed significant antimicrobial activity, susceptibility to antibiotics, acid and bile tolerance, sugar fermentation, enzymatic potential, and nonhemolytic characteristics. Interestingly, NMCC-M2 displayed the best probiotic features including survival at pH 3 and 0.5% (w/v) bile salts, complete susceptibility to the tested antibiotics, high enzymatic potential, and in vitro cholesterol reduction (48.0 µg/mL for NMCC-M2) with 0.3% bile salt supplementation. Therefore, the isolated strain NMCC-M2 could be considered as a potential target-based probiotic in cholesterol-lowering fermented food products.

In situ production of vitamin B12 and dextran in soya flour and rice bran: A tool to improve flavour and texture of B12-fortified bread

This study aimed to develop a fermentation process that allows the concomitant production of dextran (a texture-enhancing agent) and vitamin B12 (in situ fortification) for bread applications. Mixed fermentation of soya flour or rice bran using Propionibacterium freudenreichii DSM 20271 and Weissella confusa A16 with added sucrose resulted in substantial quantities of dextran (5.6–5.8% dry matter) and B12 (7.9–8.9 μg/100 g fresh weight), together with antifungal metabolites (e.g. acetic and propionic acids). In addition to an extended mould-free shelf life, the bread containing 50% (dough weight) fermented soya flour or rice bran not only contained adequate levels of B12 but also exhibited improved texture and sensory quality compared to the control, such as a higher loaf volume, a softer crumb, and a more cohesive and moister mouthfeel. The mixed fermentation reduced the beany or cooked-rice flavour but increased sour and cheesy flavours and aftertaste. Dextran produced during the fermentation process exhibited a masking effect on the beany and sour notes and aftertaste, consistently with reduced levels of green or grassy volatiles (e.g. hexanal, heptanal, (E,E)-2,4-decadienal, and 2-pentylfuran). Overall, the mixed fermentation method using P. freudenreichii DSM 20271 and W. confusa A16 showed potential for B12 fortification of bread products with high sensory quality.

Antifungal activity of lactic acid bacteria isolated from kunu-zaki, a cereal-based Nigerian fermented beverage

Fungal deterioration is a barrier to the wide acceptance of fermented cereal foods from Africa. The use of protective cultures is a natural approach to controlling fungi in foods that also complies with a clean label strategy. This study aims to select antifungal lactic acid bacteria (LAB) previously isolated from kunu-zaki to bio-control deterioration in this cereal-based Nigerian fermented beverage. Strains of Leuconostoc citreum (1), Limosilactobacillus fermentum (6), and Weissella confusa (3) were the most active against seven test mold species, with average inhibition score of 2.25–2.88, after screening 220 LAB strains using agar overlay on millet-sorghum flour hydrolysate (MSFH) agar. The MSFH agar diffusion method revealed that antifungal activity against the seven target molds was retained in cell-free supernatants (CFSs) of selected LABs, with the strongest inhibition against A. flavus F008BA and P. citrinum 3AS1 demonstrated by L. fermentum 5KJEU5 (9.06%) and W. confusa YKDIA1 (24.55%), respectively. The antifungal activity of CFSs was mainly due to the occurrence of acidic compounds, with the most abundant compounds being acetic (0.30–1.96 mg/mL) and lactic (1.80–3.23 mg/mL) acids. Other compounds such as hydroxycaffeic (0.16–6.72 μg/mL), 3-(4-hydroxyphenyl) propionic (1.40–6.36 μg/mL), 3-phenyllactic (1.28–24.48 μg/mL), and hydroxyferulic acids (12.25 μg/mL) occurred at lower concentrations. In challenged kunu-zaki, L. fermentum 5KJEU5 prevented the growth of A. flavus F008BA and P. citrinum 3AS1 beyond 8 day at ambient temperature (25 °C). In this study, LAB from kunu-zaki displayed strong antifungal activity, showing great potential as a protective culture to prevent fungal growth and mycotoxin accumulation in cereal foods.

Analysis of the structure and properties of dextran produced by Weissella confusa

An EPS produced by Weissella confusa H2 was purified through Sephadex G-100, and the preliminary structure characteristics and biological activities of H2 EPS were analyzed. Molecular mass of purified H2 EPS was 2.705 × 106 Da as measured with gel permeation chromatography (GPC). Composition of monosaccharides, nuclear magnetic resonance (NMR) spectroscopy spectroscopy and fourier transform infrared (FT-IR) showed that the EPS was a linear homopolysaccharide, mainly constituted of glucose and it is suggested that the EPS was dextran with α-(1 → 6) glycosidic bonds and a few α-(1 → 3) branches. Atomic force micrograph (AFM) and scanning electron microscopy (SEM) analysis of dextran further revealed sheets branched microstructure anchored with many irregular protuberances in aqueous solution. The XRD pattern reflected non-crystalline amorphous nature. In addition, the solubility, water-holding capacity, thermal property, rheological property and heavy metal chelating activity of the purified H2 dextran were determined. The dissolution percentage and water holding capacity of the dextran were 98.78 ± 1.37% and 426.03 ± 7.26%, respectively. The dextran exhibited good hydrophilicity, thermal stability and heavy metal chelating activity. Rheological studies exhibited rotational speed, pH, temperature, metal ions solutions dependent semiviscous nature. These results support its use as an additive in the food and environmental protection fields.

Changes in physicochemical and functional properties of Opuntia humifusa during fermentation with cellulolytic enzyme and lactic acid bacteria

Eastern prickly cactus (Opuntia humifusa) has a substantial therapeutic and dietary value. In this study, O. humifusa plants were fermented at 25 °C with cellulolytic enzymes (E, Viscozyme), lactic acid bacteria (LAB), Lactobacillus paraplantarum (Lp), Streptococcus salivarius (Ss), and Weissella confusa (Wc) in various combinations: E, LWS (Lp:Wc:Ss = 1:1:1, v/v/v), and E with LAB (E-Lp, E-Ss, E-Wc, and E–LWS). Significantly lower viscosity (14.5 cP) and higher yield (>97.4%) were observed in O. humifusa extracts containing E (P < 0.05), whereas the extract with LWS showed the highest viscosity (36.9 cP) and lowest yield (58.8%). Total polyphenol content and antioxidant activity of O. humifusa extract were enhanced, and flavonoid glycosides (isorhamnetin-3-O-rutinoside and isorhamnetin-3-O-glucoside) were effectively converted to aglycones when fermentation was performed with E and LAB. The isorhamnetin and quercetin contents were highest in the E-Wc and E-LWS extracts fermented for 60 h. This study shows that the physical and functional properties of O. humifusa extract may be modulated by fermentation with selected LAB and cellulolytic enzymes.

MALDI-TOF MS profiling and exopolysaccharide production properties of lactic acid bacteria from Kunu-zaki - A cereal-based Nigerian fermented beverage

MALDI-TOF MS is a technique for high-throughput characterization of foodborne microbiota, however, its application for studying African traditional fermented foods is limited. A total of 164 out of 220 lactic acid bacterial (LAB) isolates from Kunu-zaki were identified using MALDI-TOF MS, with 100% identity of representative strains compared to 16S rRNA gene sequencing. MALDI-TOF MS profiling combined with 16S rRNA gene sequencing revealed a total of 15 LAB species in Kunu-zaki, where the most predominant species were Lactiplantibacillus plantarum (40.46%), Weissella confusa (27.27%), and Pediococcus pentosaceus (15.00%). Phenotypic screening of all isolates revealed strains of W. confusa (57), Lactiplantibacillus sp. (9), Companilactobacillus musae (1), Ligilactobacillus saerimneri (1) and Leuconostoc citreum (1) that are capable of producing dextran and/or fructan. Dextransucrase genes were detected in all EPS-producing strains by PCR. Weissella confusa YKDIA1 and YKDIA4 produced 11.93 and 11.70 g/L dextran from millet-sorghum flour hydrolysate-sucrose, respectively. Kunu-zaki produced using W. confusa YKDIA1 had high water holding capacity (100%) and viscosity ranging from 49.46–139.24 mPas. In this study, MALDI-TOF MS adequately revealed the LAB species composition in Kunu-zaki in a high-throughput strategy and further, the dominant occurrence of EPS-producing LAB strains and their potentials to influence the rheological properties of Kunu-zaki were demonstrated.

A review of the implications of Lactic Acid Bacteria and Bifidobacteria in human and animal diseases

Lactic acid bacteria (LAB) and Bifidobacteria are taxonomically distinct groups of bacteria with proven biotechnological properties such as anti-cancer, immune-stimulating, anti-microbial, maintenance of normal flora balance, probiotics, anti-inflammatory, vaccine carriers, among others. However, studies have implicated some of them, including the ones under the European Food Safety Authority (EFSA) qualified presumption of safety in fatal human and veterinary diseases. We performed online database searches of publications on Google, Google Scholar and PubMed using the criteria, “lactic acid bacteria, bifidobacteria as causative agents of human, animal diseases”. Data generated showed LAB across genera and Bifidobacteria either primarily or opportunistically involved in diseases of both immuno-competent and immuno-depressed humans and animals. The members of lactobacilli such as Lactobacillus fermentum, Lactobacillus paracasei, Lactobacillus oris, Lactobacillus gasseri and Leuconostoc mesenteroides, were mainly implicated in nosocomial infections, endophthalmitis, neonatal meningitis, and bacteraemia while Lactobacillus delbrueckii and Bifidobacteria, specifically, Bifidobacterium longum, Bifidobacterium breve, and Bifidobacterium animalis were implicated in urinary tract infections (UTIs), necrotizing pancreatitis, fatal pulmonary infections, sepsis, and epidural abscess. The animal diseases, neonatal sepsis in foal, was caused by Weissella confusa while the fish pathogen, Lactococcus garvieae caused various zoonotic cases such as acute acalculous cholecystitis in human. In conclusion, this review showed the up-to-date reports on LAB and Bifidobacteria implicated in serious humans and animal diseases.

Oxidative stress alleviating potential of galactan exopolysaccharide from Weissella confusa KR780676 in yeast model system

In the present study, galactan exopolysaccharide (EPS) from Weissella confusa KR780676 was evaluated for its potential to alleviate oxidative stress using in vitro assays and in vivo studies in Saccharomyces cerevisiae (wild type) and its antioxidant (sod1∆, sod2∆, tsa1∆, cta2∆ and ctt1∆), anti-apoptotic (pep4∆ and fis1∆) and anti-aging (sod2∆, tsa1∆ and ctt1∆)) isogenic gene deletion mutants. Galactan exhibited strong DPPH and nitric oxide scavenging activity with an IC50 value of 450 and 138 µg/mL respectively. In the yeast mutant model, oxidative stress generated by H2O2 was extensively scavenged by galactan in the medium as confirmed using spot assays followed by fluorescencent DCF-DA staining and microscopic studies. Galactan treatment resulted in reduction in the ROS generated in the yeast mutant cells as demonstrated by decreased fluorescence intensity. Furthermore, galactan exhibited protection against oxidative damage through H2O2 -induced apoptosis inhibition in the yeast mutant strains (pep4∆ and fis1∆) leading to increased survival rate by neutralizing the oxidative stress. In the chronological life span assay, WT cells treated with galactan EPS showed 8% increase in viability whereas sod2∆ mutant showed 10–15% increase indicating pronounced anti-aging effects. Galactan from W. confusa KR780676 has immense potential to be used as a natural antioxidant for nutraceutical, pharmaceutical and food technological applications. As per our knowledge, this is the first report on in-depth assessment of in vivo antioxidant properties of a bacterial EPS in a yeast deletion model system.

Improvement of Texture, Nutritional Qualities, and Consumers’ Perceptions of Sorghum-Based Sourdough Bread Made with Pediococcus pentosaceus and Weissella confusa Strains

Enriched gluten-free products are in high demand owing to increasing celiac disease worldwide. Sourdough fermentation can improve the quality of gluten-free cereals, rendering the resulting product beneficial as a functional food. This study produced sorghum bread (SB) using sourdough technology and evaluated the texture, nutrition profile, bioactive components, and sensory attributes of the product. The base formula was composed of sorghum flour and corn starch. Sourdough made with Pediococcus pentosaceus LD7 (PL7), P. pentosaceus SA8 (PS8), or Weissella confusa SD8 (WS8) was added at a 20% substitution level for bread production, while bread without sourdough addition was used as the control sample. The texture profiles of the SB were significantly (p ˂ 0.05) softer than that of the control. The sourdough breads possessed higher crude protein, ash, and dietary fibre contents than the control bread. Tannin and total phenol contents were significantly (p ˂ 0.05) higher in the sourdough breads compared to the control sample. The specific volume of the sample made with PS8 sourdough was the highest at 2.50 cm3/g compared to the other samples (2.17–2.46 cm3/g). The sourdough samples had higher scores for taste, texture, aroma, and overall acceptability than the control, with PL7 SB exhibiting the best overall acceptability (6.56). This study established promising use of sourdough with starters as an ingredient for baked products with improved technological and nutritional attributes as well as consumer acceptability.

Signature probiotic and pharmacological attributes of lactic acid bacteria isolated from human breast milk

Maternal milk is an opulent source of lactic acid bacteria (LAB). In this study we isolated LAB possessing high probiotic and pharmaceutical potential from native Pakistani women. In total, 20 LAB strains were isolated from 69 breast milk samples, out of which 10 strains with pronounced probiotic characteristics (>90% survival in an oro-gastro-intestinal environment and exopolysaccharide secretion) were identified as Limosilactobacillus brevis, Limosilactobacillus fermentum, Weissella confusa, and Enterococcus faecalis. The strains demonstrated remarkable lactic acid (∼25 mg mL−1) production, pageant aggregation (>45%) and hydrophobicity (>50%). Moreover, they displayed distinct cation, anion, and stable free radical scavenging (>55%). Strains HM-G and HM-K revealed immunoregulatory properties by inhibiting leukocyte recruitment and IL-6 production in thioglycolate induced peritonitis model. The promising pharmaceutical properties of cell free supernatant indicate the presence of active metabolites that could be further purified for biotherapeutics or functional food production.

Alternations in the gut microbiota and metabolome with newly diagnosed unstable angina

Gut microbiota plays an important role in coronary heart disease, but its compositional and functional changes in unstable angina (UA) remain unexplored. We performed metagenomic sequencing of 133 newly diagnosed UA patients and 133 sex- and age-matched controls, and profiled the fecal and plasma metabolomes in 30 case-control pairs. The alpha diversity of gut microbiota was increased in UA patients: the adjusted odds ratios (ORs) per standard deviation increase in Shannon and Simpson indices were 1.30 (95% confidence interval, 1.01–1.70) and 1.36 (1.05–1.81), respectively. Two common species (depleted Klebsiella pneumoniae and enriched Streptococcus parasanguinis; P ≤ 0.002) and three rare species (depleted Weissella confusa, enriched Granulicatella adiacens and Erysipelotrichaceae bacterium 6_1_45; P ≤ 0.005) were associated with UA. The UA-associated gut microbiota was depleted in the pathway of L-phenylalanine degradation (P = 0.001), primarily contributed by Klebsiella pneumoniae. Consistently, we found increased circulating phenylalanine in UA patients (OR = 2.76 [1.17–8.16]). Moreover, Streptococcusparasanguinis was negatively correlated with fecal citrulline (Spearman's rs = −0.470, P = 0.009), a metabolite depleted in UA patients (OR = 0.26 [0.08–0.63]). These findings are informative to help understand the metabolic connection between gut microbiota and UA.

Investigation of gas-producing bacteria in sufu and its effective method to control their growth

The presence of gas-producing bacteria in sufu will cause the package swelling, thus significantly affecting the storage period and sensory quality of sufu. This study aimed to isolate and identify the gas-producing bacteria in sufu and provide an effective method to control their growth. The gas-producing bacteria were isolated in sufu and identified as Weissella confusa and Weissella koreensis based on 16S rDNA. W. confusa and W. koreensis still grow and produce gas in MRS broth with a salinity of 10% oralcohol of 11% content. Nisin and Lactococcus lactis were able to inhibit the growth of W. confusa and W. koreensis, while no inhibition was observed when sodium propionate, sodium dehydroacetate, and ε-polylysine hydrochloride were used. When the salinity and alcohol content was 6%, the growth of W. confusa was inhibited at MICs of nisin of 0.250 mg mL−1 and 0.125 mg mL−1, while the growth of W. koreensis was inhibited to 0.125 mg mL−1 and 0.063 mg mL−1. Nisin and L. lactis induced changes in cell morphology by disrupting membrane integrity of gas-producing bacteria. This study guides the sufu enterprises to adopt effective measures controlling the package swelling of sufu production and extending the products' storage period.

A rare case of Weissella confusa endocarditis

Weissella confusa, a Gram positive coccobacillus, is a rare cause of human disease. They are vancomycin resistant, bile aesculin positive, lactic acid fermenters previously classified as members of the Leuconostoc and Lactobacillus genera. Among the 19 recognised species of Weissella, W. confusa is most frequently associated with human infection, however as its name suggests establishing its pathogenicity and correctly identifying it using traditional phenotypic testing platforms can be challenging. We present a case of W. confusa endocarditis in a male from Ghana where W. confusa is used in the fermenting process of commonly consumed food products. We discuss the microbiological diagnostic processes, including identification of this organism through use of matrix-assisted laser-desorption ionisation/time-of-flight (MALDI-ToF), and how the laboratory derived susceptibility tests were interpreted and applied to construct a successful therapeutic regime for infective endocarditis. We review the literature around cases of invasive W. confusa disease, contextualising this organism in terms of relevance to patients who are immunocompromised or who have indwelling vascular access devices.

Antifungal activity of human gut lactic acid bacteria against aflatoxigenic Aspergillus flavus MTCC 2798 and their potential application as food biopreservative

AbstractWith the enhanced use of chemical preservatives and the survival of foodborne pathogens, lactic acid bacteria and its metabolic product have received increased attention as a potential food preservative. Even though the antibacterial property of lactic acid bacteria is well known, its antifungal property and application in food preservation have not been widely exploited. Considering these facts, this study was conducted to investigate the antifungal properties of three human gut lactic acid bacterial isolates, Lactobacillus plantarum AL1, Lactobacillus fermentum AL2, and Weissella confusa AL3 antifungal activity of the isolates were studied against the aflatoxigenic Aspergillus flavus MTCC 2798, using the agar overlay method and inhibition of fungal mycelium (co‐culture method). These LAB isolates were also potent producers of antimicrobial compounds like lactic acid, hydrogen peroxide, and diacetyl. GC–MS analysis of the methanolic extract of the three LAB isolates detected two antifungal bioactive compounds like cyclo (leucyloprolyl) and 1,2‐benzenedicarboxylic acid in extracts. The hemolysis results provided an important insight that the human gut lactic acid bacteria can be used as protective cultures in the biopreservation. The antifungal activity of human gut LAB AL1, AL2, and AL3 against aflatoxigenic Aspergillus flavus MTCC 2798 and its ability extend the shelf life of peanuts prove as a natural preservative for food products.

CAUGHT BY CONFUSA: A RARE CASE OF WEISELLA CONFUSA IN A LIVER TRANSPLANT PATIENT

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Weisella confusa is a gram-positive bacteria typically found in gut flora. It is a rare cause of bacteremia in immunocompromised patients, especially those with malignancy. When grown in blood culture isolates, it serves as a harbinger of polymicrobial infection. It is inherently vancomycin resistant and treatment is based on susceptibility panel. In this case, we demonstrate W. confusa bacteremia in the setting of broad-spectrum antibiotic prophylaxis but no immunosuppressive therapy. CASE PRESENTATION: A 57-year-old woman with ulcerative colitis and autoimmune hepatitis and primary sclerosing cholangitis (PSC) overlap requiring liver transplant complicated by recurrent PSC was admitted for odynophagia due to a tongue lesion. She developed progressive synthetic liver dysfunction resulting in altered mental status, oliguric renal failure, and Klebsiella bacteremia with concurrent C. difficile colitis. Triple immunosuppressive therapy was halted and linezolid, aztreonam and oral vancomycin were initiated. Though she completed an antibiotic course with rapid clearance of bacteremia, prophylactic meropenem, micafungin, and oral vancomycin were administered and weekly surveillance cultures were drawn in anticipation of repeat transplant.One month later, four of four blood cultures grew W. confusa, followed by Lactobacillus rhamnosus, Enterococcus faecalis, and Candida krusei soon thereafter. Antimicrobials were escalated to amphotericin B, daptomycin, aztreonam, linezolid, and metronidazole, though she developed shock requiring multiple vasopressors. Computed tomography was obtained for source identification and demonstrated a right upper lobe pulmonary abscess and multiple hepatic abscesses. Upon discussions with the patient's family, care was withdrawn and she died soon after. DISCUSSION: W. confusa is a rare isolate from blood cultures and is generally associated with polymicrobial infections. Previous studies have shown that the majority of cases occur in the setting of malignancy, though there has been one other documented case in a liver transplant patient. In addition, a study conducted in pediatric liver transplant patients demonstrated Weisella isolates in stool samples, reflecting increased gut colonization with this organism. It is a naturally vancomycin resistant organism and misidentification as Lactobacillus by traditional speciation methods often results in inappropriate therapy. Here we demonstrate a case of Weisella bacteremia likely secondary to gut translocation. Given its natural vancomycin resistance, it is likely that prophylactic oral vancomycin for C. difficile resulted in W. confusa overgrowth and facilitated her decompensation via pre-existing defects to the gut mucosal barrier from ulcerative colitis. CONCLUSIONS: W. confusa should be considered an opportunistic bacteria warranting infectious disease specialist consultation to assist in management. REFERENCE #1: 1. Kamboj, K., Vasquez, A., & Balada-Llasat, J. M. (2015). Identification and significance of Weissella species infections. Frontiers in microbiology, 6, 1204. https://doi.org/10.3389/fmicb.2015.012042. Kumar, A., Augustine, D., Sudhindran, S., et. al. (2011). Weisella confusa: a rare cause of vancomycin-resistant Gram-positive bacteremia. Journal of Medical Microbiology, 60(10), 1538-41.3. Spiegelhauer, M. R., Yusibova, M., Rasmussen, I., Fuglsang, K. A., Thomsen, K., & Andersen, L. P. (2020). A case report of polymicrobial bacteremia with Weissella confusa and comparison of previous treatment for successful recovery with a review of the literature. Access microbiology, 2(5), acmi000119. https://doi.org/10.1099/acmi.0.0001194. Green, M., Barbadora, K., & Michaels, M. (1991). Recovery of vancomycin-resistant gram-positive cocci from pediatric liver transplant recipients. Journal of clinical microbiology, 29(11), 2503–2506. https://doi.org/10.1128/JCM.29.11.2503-2506.19915. Salimnia, H., Alangaden, G. J., Bharadwaj, R., Painter, T. M., Chandrasekar, P. H., & Fairfax, M. R. (2011). Weissella confusa: an unexpected cause of vancomycin-resistant gram-positive bacteremia in immunocompromised hosts. Transplant infectious disease : an official journal of the Transplantation Society, 13(3), 294–298. https://doi.org/10.1111/j.1399-3062.2010.00586.x6. Fairfax, M. R., Lephart, P. R., & Salimnia, H. (2014). Weissella confusa: problems with identification of an opportunistic pathogen that has been found in fermented foods and proposed as a probiotic. Frontiers in microbiology, 5, 254. https://doi.org/10.3389/fmicb.2014.00254 DISCLOSURES: No relevant relationships by Samuel Chung, source=Web Response No relevant relationships by Ashwin Kelkar, source=Web Response No relevant relationships by Joseph Mailman, source=Web Response

Weissella confusa with thermostable β-hemolytic exopolysaccharide

Consuming cooked meat contaminated with bacteria that carry thermostable hemolytic exopolysaccharide (ESP), could lead to severe diseases. Culture of a 5- h boiled sample of meat goulash on blood agar showed growth of a gram positive rod-shaped, mucoid and hemolytic bacterium. Biochemical tests and amplification of 1500 bp product of 16S rDNA and sequencing revealed bacterial identity as Weissella confusa. After 1 h boiling of bacterial suspension, they were alive and hemolytic, increased in volume and aggregated. After 8 h boiling of bacterial suspension with coverslip, live bacteria showed hemolysis, clustered and adhered to coverslip. Bacterial bacteriocin and hemolytic activities remained unchanged upon autoclaving. Purified bacterial EPS retained hemolytic activity after autoclaving. Boiling contaminated meat had no negative impact on viability of heat-stable W. confusa and its hemolytic EPS. Thermostable hemolytic EPS protected W. confusa from excessive heat. Hygienic practice in butcheries and kitchens are necessary to eliminate bacterial contaminants.

Monitoring of early‐stage water uptake by hyperspectral imaging and evaluation of nutritional and technological functionality of germinated faba bean (Vicia faba L.) var. minor and var. major as food ingredients

AbstractFaba bean (Vicia faba L.) is a potential, sustainable protein alternative. Germination behavior of Vicia faba L. var. minor and Vicia faba L. var. major needs further studies in order to enable larger scale bioprocessing. In this study, early‐stage water uptake of two distinct faba bean varieties was assessed by hyperspectral imaging. Nutritional and technological functionality of germinated faba bean ingredients as such and in combination with fermentation were evaluated. Hyperspectral imaging revealed that early‐stage water uptake in faba beans occurred evenly from the different sides of the beans. Germination on petri dishes and in pilot‐scale showed that smaller faba beans moistened and germinated significantly (p &lt; 0.05) faster and retained water better through germination than larger faba beans. Germinated faba flour of minor‐type variety resulted in 72% higher dextran production in Weissella confusa VTT E‐143403 fermentation than respective native faba flour. With both types of faba bean varieties, germination as such, and with minor‐type variety, germination as combined with fermentation decreased notably the content of raffinose family oligosaccharides. These bioprocessing methods also improved functionality of faba bean ingredients by increasing protein separation efficiency in air classification, protein solubility, foaming capacity, and foam stability. Based on this study, minor‐ and major‐type or small‐ and large‐seeded faba bean varieties set different requirements to the germination process. In addition, germination alone or as combined with fermentation was proved to improve the nutritional and technological quality of faba bean material promoting its use in several food applications including also gluten‐free products.