scholarly journals Lactobacillus paracasei subsp. paracasei 8700:2 Degrades Inulin-Type Fructans Exhibiting Different Degrees of Polymerization

2005 ◽  
Vol 71 (11) ◽  
pp. 6531-6537 ◽  
Author(s):  
Lefteris Makras ◽  
Gerald Van Acker ◽  
Luc De Vuyst

ABSTRACT Ten strains of lactobacilli were assessed for their capacity to degrade inulin-type fructans, which are well-known prebiotics. Both oligofructose and inulin were tested. The dairy isolate Lactobacillus acidophilus IBB 801 degraded only oligofructose. The human isolate Lactobacillus paracasei subsp. paracasei 8700:2 degraded oligofructose and long-chain inulin and grew rapidly on both energy sources. In both cases, fractions of different degrees of polymerization were fermented. Moreover, large and short fractions of oligofructose were degraded simultaneously. When L. paracasei subsp. paracasei 8700:2 grew on oligofructose-enriched inulin, oligofructose was preferentially metabolized. In all cases, lactic acid was the main metabolic end product. Significant amounts of acetic acid, formic acid, and ethanol were produced when long-chain inulin or oligofructose-enriched inulin was used as the sole energy source.

10.5219/1062 ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 344-350 ◽  
Author(s):  
Pavel Diviš ◽  
Jaromír Pořízka ◽  
Jakub Kříkala

Drinking coffee has become part of our everyday culture. Coffee cultivation is devoted to over 50 countries in the world, located between latitudes 25 degrees North and 30 degrees South. Almost all of the world's coffee production is provided by two varieties, called ‘Arabica’ and ‘Robusta’ whereas the share of Arabica is 70% of the world's coffee harvest. Green (raw) coffee can not be used to prepare coffee beverages, coffee beans must first be roasted. Roasting coffee and reaching a certain degree of coffee roasting determine its flavor and aroma characteristics. In the present study the fate of sucrose, chlorogenic acid, acetic acid, formic acid, lactic acid, caffeic acid, total phenolic compounds and 5-hydroxymethylfurfural was studied in coffee (Brazil Cerrado Dulce, 100% Arabica) roasted in two ways (Medium roast and Full city roast). It has been found that almost all sucrose has been degraded (96 – 98%) in both roasting ways. During Medium roast 65% of chlorogenic acid contained in green coffee was degraded while during Full city roast it was 85%. During both Medium and Full city roasting, the formation of acetic acid but especially formic and lactic acid was recorded. The highest concentration of organic acids was recorded at Full City roasting at medium roasting times (3.3 mg.g-1 d.w. acetic acid, 1.79 mg.g-1 d.w. formic  acid, 0.65 mg.g-1d.w. lactic acid). The amount of phenolic substances also increased during roasting up to 16.7 mg.g-1 d.w. of gallic acid equivalent. Highest concentrations of 5-hydroxymethylfurfural were measured at medium roasting times at both Medium (0.357 mg.g-1 d.w.) and French city (0.597 mg.g-1 d.w.) roasting temperatures. At the end of roasting, the 5-hydroxymethylfurfural concentration in coffee were 0.237 mg.g-1 d.w. (Medium roast) and 0.095 mg.g-1 d.w. (Full city roast).


2019 ◽  
Vol 3 (2) ◽  
pp. 43 ◽  
Author(s):  
Nuttakul Mungma ◽  
Marlene Kienberger ◽  
Matthäus Siebenhofer

The present work develops the basics for the isolation of lactic acid, acetic acid and formic acid from a single as well as a mixed feed stream, as is present, for example, in fermentation broth for lactic acid production. Modelling of the phase equilibria data is performed using the law of mass action and shows that the acids are extracted according to their pka value, where formic acid is preferably extracted in comparison to lactic and acetic acid. Back-extraction was performed by 1 M NaHCO3 solution and shows the same tendency regarding the pka value. Based on lactic acid, the solvent phase composition, consisting of tri-n-octylamine/1-octanol/n-undecane, was optimized in terms of the distribution coefficient. The data clearly indicate that, compared to physical extraction, mass transfer can be massively enhanced by reactive extraction. With increasing tri-n-octylamine and 1-octanol concentration, the equilibrium constant increases. However, even when mass transfer increases, tri-n-octylamine concentrations above 40 wt%, lead to third phase formation, which needs to be prevented for technical application. The presented data are the basis for the transfer to liquid membrane permeation, which enables the handling of emulsion tending systems.


1968 ◽  
Vol 14 (7) ◽  
pp. 749-753 ◽  
Author(s):  
Yu-Ying F. Li ◽  
Lucille K. Georg

Gas–liquid chromatography (g.l.c.) was used for the analysis of certain metabolic end products of Actinomyces propionicus, as an aid in the separation of this organism from the morphologically similar Actinomyces species, A. israelii and A. naeslundii. Profiles of the chromatograms for the major volatile acids of five strains of A. propionicus studied were found to be distinct from those of four strains of A. israelii and four strains of A. naeslundii. The ratio of propionic acid to acetic acid was approximately 50 times as great for A. propionicus as for the other Actinomyces species. Formic acid was present in significant amounts in both A. israelii and A. naeslundii, but was present only in trace amounts in A. propionicus.Two major nonvolatile acids, lactic and succinic, were identified for the A. israelii and A. naeslundii strains. One of the A. propionicus strains also showed both acids in significant amounts; however, the other four strains of A. propionicus showed succinic acid in large amounts, but only trace amounts of lactic acid.


2012 ◽  
Vol 57 (8) ◽  
pp. 2102-2108 ◽  
Author(s):  
Hee-Geun Nam ◽  
Geon-Woo Lim ◽  
Sungyong Mun

Author(s):  
Yong Jun Goh ◽  
Rodolphe Barrangou

Diverse Lactobacillus strains are widely used as probiotic cultures in the dairy and dietary supplements industries, and specific strains such as Lactobacillus acidophilus NCFM have been engineered for the development of biotherapeutics. To expand the Lactobacillus manipulation toolbox with enhanced efficiency and ease, we present here a CRISPR-SpyCas9D10A nickase (Cas9N)-based system for programmable engineering of L. acidophilus NCFM, a model probiotic bacterium. Successful single-plasmid delivery system was achieved with the engineered pLbCas9N vector harboring cas9N under the regulation of a Lactobacillus promoter and a cloning region for customized sgRNA and editing template. The functionality of the pLbCas9N system was validated in NCFM with targeted chromosomal deletions ranging between 300 bp and 1.9 kb at various loci (rafE, lacS and ltaS), yielding 35-100% mutant recovery rates. Genome analysis of the mutants confirmed precision and specificity of the pLbCas9N system. To showcase the versatility of this system, we also inserted a mCherry fluorescent protein gene downstream of the pgm gene to create a polycistronic transcript. The pLbCas9N system was further deployed in other species to generate concurrent single base substitution and gene deletion in Lactobacillus gasseri ATCC 33323, and an in-frame gene deletion in Lactobacillus paracasei Lpc-37, highlighting the portability of the system in phylogenetically distant Lactobacillus species, where its targeting activity was not interfered by endogenous CRISPR-Cas systems. Collectively, these editing outcomes illustrate the robustness and versatility of the pLbCas9N system for genome manipulations in diverse lactobacilli, and open new avenues for the engineering of health-promoting lactic acid bacteria. Importance This work describes the development of a broad-host range CRISPR-based editing system for genome manipulations in three Lactobacillus species, which belong to lactic acid bacteria (LAB) commonly known for their long history of use in food fermentations and as indigenous members of healthy microbiota, and their emerging roles in human and animal commercial health-promoting applications.  We exploited the established CRISPR-SpyCas9 nickase for flexible and precise genome editing applications in Lactobacillus acidophilus, and further demonstrated the efficacy of this universal system in two distantly related Lactobacillus species.  This versatile Cas9-based system facilitates genome engineering compared to conventional gene replacement systems, and represents a valuable gene editing modality in species that do not possess native CRISPR-Cas systems.  Overall, this portable tool contributes to expanding the genome editing toolbox of LAB for studying their health-promoting mechanisms and engineering of these beneficial microbes as next-generation vaccines and designer probiotics.


2014 ◽  
Vol 32 (No. 6) ◽  
pp. 526-531 ◽  
Author(s):  
Š. Horáčková ◽  
P. Sedláčková ◽  
M. Sluková ◽  
M. Plocková

The effect of whey powder, whey protein concentrate, caseinomacropeptide, and malt addition into milk on the growth and acid production of lactobacilli (Lactobacillus casei Lafti L-26, Lactobacillus acidophilus CCDM 151, and Lactobacillus casei CCDM 198) was evaluated. The ability of these strains to use different types of saccharides from milk and plant sources was also tested. Glucose, galactose, fructose and maltose were utilised by all tested strains. The results showed that the addition of malt positively affected the growth of lactobacilli strains compared to the growth in milk enriched by whey ingredients. The addition of malt increased significantly the production of d(–)isomer of lactic acid by Lactobacillus acidophilus CCDM 151 and Lactobacillus casei CCDM 198 and the production of acetic acid by Lactobacillus casei CCDM 198.  


1942 ◽  
Vol 6a (1) ◽  
pp. 45-52 ◽  
Author(s):  
G. J. Sigurdsson ◽  
A. J. Wood

The products of fermentation of glucose by "resting cell" suspensions of certain bacteria (Serratia, Achromobacter, and Micrococcus) isolated from decomposing cod muscle include lactic acid, acetic acid, formic acid, ethyl alcohol, carbon dioxide and small amounts of acetylmethylcarbinol. With increased acidity in the fermentation system there is a marked increase in the percentage of lactic acid formed, with a corresponding decrease in the other products. The optimum pH for the fermentation of glucose appears to be in the vicinity of 6.8—that is at, or near, the pH of fresh cod muscle.


Author(s):  
Stanislav Hejduk ◽  
Petr Doležal

The effect of broad-leaved dock (BLD) on nutritive value and fermentation process of grassland fo­ra­ges was studied together with the effect of formic acid addition (4.0 vs. 2.0 l.t−1) and inoculation by lactic acid bacteria (LAB). Herbage of dock exhibits low DM content, crude protein and fibre contents, yet its NEL concentration is low.Despite of the low DM content in BLD silages, the fermentation process was successful, but the si­la­ges show significantly higher contents of lactic acid (176.5 %), acetic acid (198.2 %) and lover pH va­lues (4.24 vs. 4.39) as compared with than the grass silage. Silages made of dock do not contain bu­ty­ric acid and exhibit low rates of proteolysis (9.2 % NH3 from total N). Addition of formic acid shows in the group of assessed silages significant reduction content of lactic acid (−6.5 %) and acetic acid (−9.3 %) and significant decrease of pH value (−0.05). The use of probiotic preparation leads to significantly higher lactic acid production (+39.3 %) and to lover pH value (−0.23) as compare with control without additions.


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