TL;DR: In this paper, the authors reported the isolation and characterization of pathogenic Vibrio spp. and lactic acid bacteria from an intensive culture system of Litopenaeus vannamei and natural ecosystem, respectively.
Abstract: Probiotics inspired by host-microbe interactions in the natural ecosystem are propitious in controlling bacterial infections in aquaculture and veterinary systems. Here we report the isolation and characterization of pathogenic Vibrio spp. and lactic acid bacteria from an intensive culture system of Litopenaeus vannamei and natural ecosystem, respectively. The pathogen isolated from the gut of L. vannamei showing the symptoms of white gut disease were identified as V. parahaemolyticus and V. campbelli. Both the pathogens expressed the virulence genes, rtxA, and tcpA and were showing multiple antibiotic resistance (MAR) index of more than 0.5. The lactic acid bacteria isolated from the sediment and gut of benthic organisms (shrimp and polychaetes) collected from a tropical estuary were classified as member of 9 OTUs such as Pediococcus stilessi, Lactobacillus fermentum, L. rhamnosus, Weissella cibaria, Enterococcus durans, E. fecalis, Streptococcus gallolyticus and L. garvieae. Majority of these isolates were facultative in nature and were able to tolerate gastric juice and bile salt. Out of 83 bacteria isolated from sediment and gut, 36 showed abilities to reduce the pH of culture medium to less than five. Many of these isolates (34 Nos.) showed production of hydrolytic enzymes and secondary metabolites with antagonistic activity against both the pathogens (1 No.) or separately toward V. parahaemolyticus (9 Nos.) and V. campbelli (11 Nos.). Overall, the current study proposes a natural ecosystem as a potential source of lactic acid bacteria with probiotic potentials to prevent the vibriosis disease outbreaks in shrimp aquaculture systems. Further studies are required to understand the abilities of lactic acid bacteria to colonize shrimp intestine, stimulate immune system and manipulate microbiome.
TL;DR: Investigation of isolates to grow on inulin showed Pediococcus acidilactici isolate BE was able to consume inulin as the only carbon source and be subject to further in vivo evaluation using animal models to examine their beneficial health effects.
Abstract: The aim of this experiment was to identify isolates obtained from feces of Indonesian infants and to evaluate their capability as probiotics. Identification of isolates was carried out based on morphology, physiology and biochemical identifications, and molecular identification based on 16S rRNA sequence. Morphological and physiological identification was carried out based on Gram staining, shape, motility, spore formation and catalase production. Biochemical identifications based on production of CO2 and NH3 from glucose, the ability to grow on different temperature (10 and 45°C) and pH (4.4 and 9.6), and different salt concentration (6.5 and 18%). Probiotics capability of isolates was assayed on the ability to grow on low pH (pH 2.0), on different bile salts concentration (0.3; 0.5; 1.0 and 1.5%), the capacity to grow on media with inulin as the only carbon source, and in vitro adhesion ability on porcine mucin. Morphological, physiological and biochemical identification suggest that all of isolates belong to lactic acid bacteria. Further molecular identification of five isolates showed that isolates AA, BE and BK were strains of Pediococcus acidilactici (similarity 99%), while isolate AP and AG were strains of Lactobacillus casei (similarity 99-100%). Probiotic assays showed that more than 80% of cells of Pediococcus acidilactici isolates AA, BE and BK were viable after grown on pH 2.0 for 90 min, and around 80% of cells from the same isolates were survived on media supplemented with bile salt 1.5% for 2 h. All of isolates had high adhesion capacity as seen by more than 75% of cells attached on pig gastric mucin. Investigation of isolates to grow on inulin showed Pediococcus acidilactici isolate BE was able to consume inulin as the only carbon source. It is concluded that Pediococcus acidilactici isolate BE was a candidate probiotics and subject to further in vivo evaluation using animal models to examine their beneficial health effects. Key word : Pediococcus acidilactici, Lactobacillus casei, human origin and probiotics.
TL;DR: In this paper , the authors evaluated a potential probiotic from the antioxidant perspective, which was revealed to be Pediococcus acidilactici on the basis of its morphological, biochemical, and molecular characteristics.
Abstract: Growing interest has been focused on lactic acid bacteria as alternatives to antimicrobial growth promoters, which are characterized by the production of various functional metabolites, such as antimicrobial and antioxidants compounds. The present study was undertaken to evaluate a potential probiotic from the antioxidant perspective. LC-9-1, screened from the intestines of healthy animals, was revealed to be Pediococcus acidilactici on the basis of its morphological, biochemical, and molecular characteristics. The strain has excellent properties, including acid-production efficiency, antibacterial performance and antioxidant activity. The safety of the strain was also evaluated. Furthermore, the experiments in broiler chickens suggested that dietary LC-9-1 supplementation improved the growth performance and decreased the abdominal fat, and enhanced the antioxidant capability and intestinal innate immunity of broilers. Analysis of intestinal microbiota showed that a higher community diversity (Shannon index) was achieved. In addition to the significantly increased relative abundances of Pediococcus spp., beneficial genera such as Rothia spp. and Ruminococcus spp. were abundant, while opportunistic pathogens such as Escherichia-Shigella spp. were significantly reduced in LC-9-1-supplemented broilers. Collectively, such in-depth characterization and the available data will guide future efforts to develop next-generation probiotics, and LC-9-1 could be considered a potential strain for further utilization in direct-fed microbial or starter culture for fermentation.
TL;DR: Among non-lactobacilli LAB, the genera with the best AFB1 binding abilities were genus Pediococcus, with a maximum binding percentage of 7.6% by P. acidilactici OR83, followed by genus Lactococcus.
Abstract: Research on the ability of lactic acid bacteria (LAB) to bind aflatoxin B1 (AFB1) has mostly been focusing on lactobacilli and bifidobacteria. In this study, the AFB1 binding capacities of 20 Enterococcus strains belonging to E. casseliflavus, E. faecalis, E. faecium, E. hirae, E. lactis, and E. mundtii, 24 Pediococcus strains belonging to species P. acidilactici, P. lolii, P. pentosaceus, and P. stilesii, one strain of Lactococcus formosensis and L.garviae, and 3 strains of Weissella soli were investigated in MRS broth at 37 °C at 0.2 µg/mL mycotoxin concentration. According to our results, among non-lactobacilli LAB, the genera with the best AFB1 binding abilities were genus Pediococcus, with a maximum binding percentage of 7.6% by P. acidilactici OR83, followed by genus Lactococcus. For AFB1 bio-detoxification purposes, beside lactobacilli, pediococci can also be chosen, but it is important to select a strain with better binding properties than the average value of its genus. Five Pediococcus strains have been selected to compare their sterigmatocystin (ST) binding abilities to AFB1 binding, and a 2-3-fold difference was obtained similar to previous findings for lactobacilli. The best strain was P. acidilactici OR83 with 18% ST binding capacity. This is the first report on ST binding capabilities of non-Lactobacillus LAB strains.
TL;DR: Lactic acid bacteria (LAB) consist of a number of bacterial genera within the phylum Firmicutes and are regarded as a major group of probiotic bacteria.
Abstract: Lactic acid bacteria (LAB) consist of a number of bacterial genera within the phylum Firmicutes. The genera Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Lactosphaera, Leuconostoc, Melissococcus, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella are recognized as LAB (Jay, 2000; Ercolini et al., 2001; Holzapfel et al., 2001). Lactic acid bacteria (LAB) have played a long and important role in food technology. The LAB include a wide variety of cell types and physiological and biochemical characteristics. They are often associated with animal oral cavities and intestines e.g. Enterococcus faecalis and plant leaves Lactobacillus, Leuconostoc (Savadogo et al., 2006). They occur naturally in fermented food (Caplice and Fitzgerald, 1999) and have been detected in soil, water, manure and sewage (Holzapfel et al., 2001). Lactic acid bacteria are regarded as a major group of probiotic bacteria (Collins et al., 1998; Tannock, 1998; Schrezenmeir and de Vrese, 2001). Isolations of LAB, from the products of milk, fermented foods and plants have been frequently reported but studies on the isolation from soil remain scarce (Chen et al., 2005), although it is well known that spore-forming LAB exist International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 3 Number 3 (2014) pp. 991-998 http://www.ijcmas.com