scholarly journals Yeasts and Lactic Acid Bacteria for Panettone Production: An Assessment of Candidate Strains

2021 ◽  
Vol 9 (5) ◽  
pp. 1093
Author(s):  
Luciana De Vero ◽  
Giovanna Iosca ◽  
Salvatore La China ◽  
Fabio Licciardello ◽  
Maria Gullo ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Leuconostoc Mesenteroides ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
D2 Domain ◽  
Volatile Organic ◽  
Agar Media ◽  
26S Rrna ◽  
Selection Of

The recovery of yeasts and lactic acid bacteria (LAB) involved in sourdough fermentation is the first step in the selection of starters with suitable technological aptitude and capable of producing desired aromas and/or aromatic precursors. In this work, two sourdoughs samples (MA and MB) and the derived doughs (samples A and B) were collected from a bakery during artisanal Panettone manufacture. Yeasts and bacteria were isolated at different fermentation steps on selective agar media. A total of 77 isolates were obtained and characterized. Representative strains of yeasts and LAB were identified by sequencing the D1/D2 domain of the 26S rRNA and the 16S rRNA genes, respectively. Moreover, the volatile organic compounds (VOCs) produced in the collected samples were detected and correlated to the species found in the same samples. The results highlighted the occurrence of Kazachstania humilis in both samples A and B, while Saccharomyces cerevisiae strains were detected only in samples B. Among LAB, Fructilactobacillus sanfranciscensis was the main species detected in both sourdoughs. Furthermore, strains belonging to the species Lactiplantibacillus plantarum, Furfurilactobacillus rossiae, Lactobacillus parabuchneri, Leuconostoc citreum, and Leuconostoc mesenteroides were assessed in the dough samples.

scholarly journals Exploring the Microbial Community of Traditional Sourdoughs to Select Yeasts and Lactic Acid Bacteria

Proceedings ◽  
2020 ◽  
Vol 66 (1) ◽  
pp. 3
Author(s):  
Giovanna Iosca ◽  
Luciana De Vero ◽  
Maria Gullo ◽  
Fabio Licciardello ◽  
Andrea Quartieri ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Starter Cultures ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
D2 Domain ◽  
Microbiological Methods ◽  
Agar Media ◽  
26S Rrna ◽  
Staphylococcus Spp

Sourdoughs represent an awesome example of ecosystem in which yeasts and lactic acid bacteria (LAB) interact with each other, defining the characteristics of the final product in terms of composition, texture, taste and flavor. Therefore, the identification of dominant yeasts and LAB involved in the fermentation process can lead to the selection of starters with suitable fermentation aptitude and capable of producing desired aromas and/or aromatic precursors. In this work, two sourdoughs samples (A and B) for Panettone production were collected from an artisan bakery. Yeasts and bacteria were isolated at different fermentation steps on selective agar media. A total of 120 isolates were obtained and firstly characterized by conventional microbiological methods. Afterward, genomic DNA was extracted from the cultures, and (GTG)5-PCR fingerprinting analysis was carried out to reduce the redundance among the isolates. Representative yeasts and LAB strains, having a unique profile, were identified by sequencing the D1/D2 domain of the 26S rRNA and the 16S rRNA genes, respectively. The results highlighted the occurrence of Kazachstania humilis and Fructilactobacillus sanfranciscensis in both sourdoughs. Among LAB, also some other strains belonging to Lactobacillus genus were found. Moreover, Saccharomyces cerevisiae and Staphylococcus spp. strains were detected in sample B. In this study, a pool of yeasts and LAB strains for producing starter cultures with specific technological traits for sourdoughs production was obtained.

scholarly journals Role of Broiler Carcasses and Processing Plant Air in Contamination of Modified-Atmosphere-Packaged Broiler Products with Psychrotrophic Lactic Acid Bacteria

2006 ◽  
Vol 73 (4) ◽  
pp. 1136-1145 ◽  
Author(s):  
Elina Vihavainen ◽  
Hanna-Saara Lundstr�m ◽  
Tuija Susiluoto ◽  
Joanna Koort ◽  
Lars Paulin ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
23S Rrna ◽  
Processing Plant ◽  
Modified Atmosphere ◽  
Production Plant ◽  
Meat Spoilage

ABSTRACT Some psychrotrophic lactic acid bacteria (LAB) are specific meat spoilage organisms in modified-atmosphere-packaged (MAP), cold-stored meat products. To determine if incoming broilers or the production plant environment is a source of spoilage LAB, a total of 86, 122, and 447 LAB isolates from broiler carcasses, production plant air, and MAP broiler products, respectively, were characterized using a library of HindIII restriction fragment length polymorphism (RFLP) patterns of the 16 and 23S rRNA genes as operational taxonomic units in numerical analyses. Six hundred thirteen LAB isolates from the total of 655 clustered in 29 groups considered to be species specific. Sixty-four percent of product isolates clustered either with Carnobacterium divergens or with Carnobacterium maltaromaticum type strains. The third major product-associated cluster (17% of isolates) was formed by unknown LAB. Representative strains from these three clusters were analyzed for the phylogeny of their 16S rRNA genes. This analysis verified that the two largest RFLP clusters consisted of carnobacteria and showed that the unknown LAB group consisted of Lactococcus spp. No product-associated LAB were detected in broiler carcasses sampled at the beginning of slaughter, whereas carnobacteria and lactococci, along with some other specific meat spoilage LAB, were recovered from processing plant air at many sites. This study reveals that incoming broiler chickens are not major sources of psychrotrophic spoilage LAB, whereas the detection of these organisms from the air of the processing environment highlights the role of processing facilities as sources of LAB contamination.

scholarly journals Diversity of Lactic Acid Bacteria Associated with Fish and the Fish Farm Environment, Established by Amplified rRNA Gene Restriction Analysis

2007 ◽  
Vol 73 (9) ◽  
pp. 2947-2955 ◽  
Author(s):  
Christian Michel ◽  
Claire Pelletier ◽  
Mekki Boussaha ◽  
Diane-Gaëlle Douet ◽  
Armand Lautraite ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Opportunistic Infections ◽  
Restriction Analysis ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Fish Food ◽  
Group A ◽  
Gene Restriction

ABSTRACT Lactic acid bacteria have become a major source of concern for aquaculture in recent decades. In addition to true pathogenic species of worldwide significance, such as Streptococcus iniae and Lactococcus garvieae, several species have been reported to produce occasional fish mortalities in limited geographic areas, and many unidentifiable or ill-defined isolates are regularly isolated from fish or fish products. To clarify the nature and prevalence of different fish-associated bacteria belonging to the lactic acid bacterium group, a collection of 57 isolates of different origins was studied and compared with a set of 22 type strains, using amplified rRNA gene restriction analysis (ARDRA). Twelve distinct clusters were delineated on the basis of ARDRA profiles and were confirmed by sequencing of sodA and 16S rRNA genes. These clusters included the following: Lactococcus raffinolactis, L. garvieae, Lactococcus l., S. iniae, S. dysgalactiae, S. parauberis, S. agalactiae, Carnobacterium spp., the Enterococcus “faecium” group, a heterogeneous Enterococcus-like cluster comprising indiscernible representatives of Vagococcus fluvialis or the recently recognized V. carniphilus, V. salmoninarum, and Aerococcus spp. Interestingly, the L. lactis and L. raffinolactis clusters appeared to include many commensals of fish, so opportunistic infections caused by these species cannot be disregarded. The significance for fish populations and fish food processing of three or four genetic clusters of uncertain or complex definition, namely, Aerococcus and Enterococcus clusters, should be established more accurately.

scholarly journals In-Vitro Characterization of Growth Inhibition against the Gut Pathogen of Potentially Probiotic Lactic Acid Bacteria Strains Isolated from Fermented Products

2021 ◽  
Vol 9 (10) ◽  
pp. 2141
Author(s):  
Ji Young Jung ◽  
Sang-Soo Han ◽  
Z-Hun Kim ◽  
Myung Hoo Kim ◽  
Hye Kyeong Kang ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Intestinal Microbiota ◽  
Cell Surface Hydrophobicity ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
In Vitro Assays ◽  
The Impact ◽  
Fermented Products

Lactic acid bacteria (LAB) are probiotic candidates that may restore the balance of microbiota populations in intestinal microbial ecosystems by controlling pathogens and thereby promoting host health. The goal of this study was to isolate potential probiotic LAB strains and characterize their antimicrobial abilities against pathogens in intestinal microbiota. Among 54 LAB strains isolated from fermented products, five LAB strains (NSMJ15, NSMJ16, NSMJ23, NSMJ42, and NFFJ04) were selected as potential probiotic candidates based on in vitro assays of acid and bile salt tolerance, cell surface hydrophobicity, adhesion to the intestinal epithelium, and antagonistic activity. Phylogenetic analysis based on 16S rRNA genes showed that they have high similarities of 99.58–100% to Lacticaseibacillus paracasei strains NSMJ15 and NFFJ04, Lentilactobacillus parabuchneri NSMJ16, Levilactobacillus brevis NSMJ23, and Schleiferilactobacillus harbinensis NSMJ42. To characterize their antimicrobial abilities against pathogens in intestinal microbiota, the impact of cell-free supernatant (CFS) treatment in 10% (v/v) fecal suspensions prepared using pooled cattle feces was investigated using in vitro batch cultures. Bacterial community analysis using rRNA amplicon sequencing for control and CFS-treated fecal samples at 8 and 16 h incubation showed the compositional change after CFS treatment for all five LAB strains. The changed compositions were similar among them, but there were few variable increases or decreases in some bacterial groups. Interestingly, as major genera that could exhibit pathogenicity and antibiotic resistance, the members of Bacillus, Escherichia, Leclercia, Morganella, and Vagococcus were decreased at 16 h in all CFS-treated samples. Species-level classification suggested that the five LAB strains are antagonistic to gut pathogens. This study showed the probiotic potential of the five selected LAB strains; in particular, their antimicrobial properties against pathogens present in the intestinal microbiota. These strains would therefore seem to play an important role in modulating the intestinal microbiome of the host.

Isolation and molecular identification of lactic acid bacteria and Bifidobacterium spp. from faeces of the blue-fronted Amazon parrot in Brazil

2014 ◽  
Vol 5 (4) ◽  
pp. 497-503 ◽  
Author(s):  
L. Allegretti ◽  
L. Revolledo ◽  
C.S. Astolfi-Ferreira ◽  
J.L. Chacón ◽  
L.M. Martins ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Habitat Management ◽  
Bacterial Species ◽  
Bifidobacterium Bifidum ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Lactobacillus Species ◽  
Faecal Microbiota ◽  
Lactobacillus Coryniformis

In Brazil, the blue-fronted Amazon parrot (Amazona aestiva) is a common pet. The faecal microbiota of these birds include a wide variety of bacterial species, the majority of which belong to the Gram-positive lactic acid bacteria (LAB) clade. The aim of this study was to investigate differences in the diversity and abundance of LAB and Bifidobacterium spp. in the cloacae between wild and captive birds and to select, identify and characterise LAB for consideration as a parrot probiotic. Cloacal swabs were collected from 26 wild and 26 captive birds. Bacterial DNA was extracted, and the 16S rRNA genes were amplified. The numbers of PCR-positive Enterococcus, Pediococcus, and Lactobacillus species isolated from wild and captive birds were significantly different (P<0.05). Enterococcus was the most frequently isolated genus, followed by Pediococcus, Lactobacillus, Lactococcus and Bifidobacterium. Enterococcus faecium, Pediococcus pentosaceus, Lactococcus lactis, Lactobacillus coryniformis, Lactobacillus sanfranciscensis and Bifidobacterium bifidum were the most frequently isolated species from all birds. This study increases our understanding of the faecal microbiota, and may help to improve the nutrition and habitat management of captive and wild parrots. The bacterial population identified in the faecal microbiota of clinically healthy wild and captive parrots can serve as a database to analyse variations in the gut microbiota of pathogen-infected parrots and to develop probiotics specific to these genera.

scholarly journals Isolation and Molecular Identification of Lactic Acid Bacteria Using 16s rRNA Genes from FermentedTeff(Eragrostis tef(Zucc.)) Dough

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Belay Tilahun ◽  
Anteneh Tesfaye ◽  
Diriba Muleta ◽  
Andualem Bahiru ◽  
Zewdu Terefework ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
16S Rrna ◽  
Addis Ababa ◽  
Bacterial Species ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Eragrostis Tef ◽  
Universal Primers ◽  
Bacterial Isolates

Injera is soft fermented baked product, which is commonly prepared from teff (Eragrostis tef(Zucc.)) flour and believed to be consumed on daily basis by two-thirds of Ethiopians.As it is a product of naturally fermented dough, the course of fermentation is done by consortia of microorganisms. The study was aimed at isolating and identifying some dominant bacteria from fermentingteff (Eragrostis tef)dough. A total of 97 dough samples were collected from households, microenterprises, and hotels with different fermentation stage from Addis Ababa. The bacterial isolates obtained from the fermentingteffdough samples were selected on the basis of their acid production potentials. A total of 24 purified bacterial isolates were found to be Gram-positive (they are coccus and rod under microscope) and were good acid producers. Genomic DNA of bacterial isolates were extracted using Invisorb® Spin DNA Extraction kit. 16S rRNA of bacterial isolates were amplified using the bacteria universal primers (rD1 and fD1). The amplified product was sequenced at Genewiz, USA. Sequence analysis and comparison with the resources at the database were conducted to identify the isolated microbes into species and strain levels. The bacterial isolates were identified asLactobacillus paracasei, Lactobacillus brevis, Enterococcus durans, Enterococcus hirae, Enterococcus avium,andEnterococcus faecium. All identified lactic acid bacteria were able to produce acid at 12 h time of incubation. This study has confirmed the presence of different bacterial species in the fermentingteffdough and also supports the involvement of various groups of bacterial species in the course of the fermentation.

scholarly journals Halolactibacillus halophilus gen. nov., sp. nov. and Halolactibacillus miurensis sp. nov., halophilic and alkaliphilic marine lactic acid bacteria constituting a phylogenetic lineage in Bacillus rRNA group 1

2005 ◽  
Vol 55 (6) ◽  
pp. 2427-2439 ◽  
Author(s):  
Morio Ishikawa ◽  
Kazuyuki Nakajima ◽  
Yuko Itamiya ◽  
Sayumi Furukawa ◽  
Yasushi Yamamoto ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Optimal Growth ◽  
Comparative Sequence Analysis ◽  
Diaminopimelic Acid ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Molar Ratio ◽  
Fermentation Products ◽  
Group 1

Eleven novel strains of marine-inhabiting lactic acid bacteria that were isolated from living and decaying marine organisms collected from a temperate area of Japan are described. The isolates were motile with peritrichous flagella and non-sporulating. They lacked catalase, quinones and cytochromes. Fermentation products from glucose were lactate, formate, acetate and ethanol. Lactate yield as percentage conversion from glucose was affected by the pH of the fermentation medium: ∼55 % at the optimal growth pH of 8·0, greater than ∼70 % at pH 7·0 and less than ∼30 % at pH 9·0. The molar ratio of the other three products was the same at each cultivation pH, approximately 2 : 1 : 1. Carbohydrates and related compounds were aerobically metabolized to acetate and pyruvate as well as lactate. The isolates were slightly halophilic, highly halotolerant and alkaliphilic. The optimum NaCl concentration for growth was 2·0–3·0 % (w/v), with a range of 0–25·5 %. The optimum pH for growth was 8·0–9·5, with a range of 6·0–10·0. The G+C content of the DNA was 38·5–40·7 mol%. The isolates constituted two genomic species (DNA–DNA relatedness of less than 41 %) each characterized by sugar fermentation profiles. The cell-wall peptidoglycan of both phenotypes contained meso-diaminopimelic acid. The major cellular fatty acids were C16 : 0 and a-C13 : 0. Comparative sequence analysis of the 16S rRNA genes revealed that these isolates represent novel species constituting a phylogenetic unit outside the radiation of typical lactic acid bacteria and an independent line of descent within the group composed of the halophilic/halotolerant/alkaliphilic and/or alkalitolerant species in Bacillus rRNA group 1, with 94·8–95·1 % similarity to the genus Paraliobacillus, 93·7–94·1 % to the genus Gracilibacillus and 93·8–94·2 % to Virgibacillus marismortui. On the basis of possession of physiological and biochemical characteristics common to typical lactic acid bacteria within Bacillus rRNA group 1, chemotaxonomic characteristics and phylogenetic independence, a new genus and two species, Halolactibacillus halophilus gen. nov., sp. nov. and Halolatibacillus miurensis sp. nov., are proposed. The type strains are Halolactibacillus halophilus M2-2T (=DSM 17073T=IAM 15242T=NBRC 100868T=NRIC 0628T) (G+C content 40·2 mol%) and Halolactibacillus miurensis M23-1T (=DSM 17074T=IAM 15247T=NBRC 100873T=NRIC 0633T) (G+C content 38·5 mol%).

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