Core Fluxome and Metafluxome of Lactic Acid Bacteria under Simulated Cocoa Pulp Fermentation Conditions

ABSTRACTIn the present work, simulated cocoa fermentation was investigated at the level of metabolic pathway fluxes (fluxome) of lactic acid bacteria (LAB), which are typically found in the microbial consortium known to convert nutrients from the cocoa pulp into organic acids. A comprehensive13C labeling approach allowed to quantify carbon fluxes during simulated cocoa fermentation by (i) parallel13C studies with [13C6]glucose, [1,2-13C2]glucose, and [13C6]fructose, respectively, (ii) gas chromatography-mass spectrometry (GC/MS) analysis of secreted acetate and lactate, (iii) stoichiometric profiling, and (iv) isotopomer modeling for flux calculation. The study of several strains ofL. fermentumandL. plantarumrevealed major differences in their fluxes. TheL. fermentumstrains channeled only a small amount (4 to 6%) of fructose into central metabolism, i.e., the phosphoketolase pathway, whereas onlyL. fermentumNCC 575 used fructose to form mannitol. In contrast,L. plantarumstrains exhibited a high glycolytic flux. All strains differed in acetate flux, which originated from fractions of citrate (25 to 80%) and corresponding amounts of glucose and fructose. Subsequent, metafluxome studies with consortia of differentL. fermentumandL. plantarumstrains indicated a dominant (96%) contribution ofL. fermentumNCC 575 to the overall flux in the microbial community, a scenario that was not observed for the other strains. This highlights the idea that individual LAB strains vary in their metabolic contribution to the overall fermentation process and opens up new routes toward streamlined starter cultures.L. fermentumNCC 575 might be one candidate due to its superior performance in flux activity.

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Fermentation Enhanced Biotransformation of Compounds in the Kernel of Chrysophyllum albidum

Molecules ◽

10.3390/molecules25246021 ◽

2020 ◽

Vol 25 (24) ◽

pp. 6021

Author(s):

Oluwatofunmi E. Odutayo ◽

Emmanuel A. Omonigbehin ◽

Tolulope D. Olawole ◽

Olubanke O. Ogunlana ◽

Israel S. Afolabi

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Cultures ◽

Gas Chromatography Mass Spectrometry ◽

Bile Salt Hydrolase ◽

Aqueous Extracts ◽

Acidic Environment ◽

African Star Apple

Chrysophyllum albidum Linn (African star apple) is a fruit with extensive nutritional and medicinal benefits. The fruit and kernel in the seed are both edible. Strains of lactic acid bacteria (LAB) were isolated from fermented seeds and assessed for probiotic characteristics. The extracts in both the unfermented and the fermented aqueous extracts from the kernels obtained from the seeds of C. albidum were subjected to analysis using the gas chromatography/mass spectrometry (GC-MS) method. This analysis identified the bioactive compounds present as possible substrate(s) for the associated organisms inducing the fermentation and the resultant biotransformed products formed. Three potential probiotic LAB strains identified as Lactococcus raffinolactis (ProbtA1), Lactococcus lactis (ProbtA2a), and Pediococcus pentosaceus (ProbtA2b) were isolated from the fermented C. albidum seeds. All strains were non hemolytic, which indicated their safety, Probt (A1, A2a, and A2b) grew in an acidic environment (pH 3.5) during the 48-h incubation time, and all three strains grew in 1% bile, and exhibited good hydrophobicity and auto-aggregation properties. Mucin binding proteins was not detected in any strain, and bile salt hydrolase was detected in all the strains. l-lactic acid (28.57%), norharman (5.07%), formyl 7E-hexadecenoate (1.73%), and indole (1.51%) were the four major constituents of the fermented kernel of the C. albidum, while 2,5-dimethylpyrazine (C1, 1.27%), 3,5-dihydroxy-6-methyl-2,3-dihydropyran-4-one (C2, 2.90%), indole (C3, 1.31%), norharman (C4, 3.01%), and methyl petroselinate (C5, 4.33%) were the five major constituents of the unfermented kernels. The isolated LAB are safe for consumption. The fermenting process metabolized C1, C2, and C5, which are possible starter cultures for the growth of probiotics. Fermentation is an essential tool for bioengineering molecules in foods into safe and health beneficial products.

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Metabolism of Fructophilic Lactic Acid Bacteria Isolated from the Apis mellifera L. Bee Gut: Phenolic Acids as External Electron Acceptors

Applied and Environmental Microbiology ◽

10.1128/aem.02194-16 ◽

2016 ◽

Vol 82 (23) ◽

pp. 6899-6911 ◽

Cited By ~ 25

Author(s):

Pasquale Filannino ◽

Raffaella Di Cagno ◽

Rocco Addante ◽

Erica Pontonio ◽

Marco Gobbetti

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Phenolic Acids ◽

Electron Acceptors ◽

Starter Cultures ◽

Fermented Foods ◽

Coumaric Acid ◽

Content Type ◽

Phenotypic Microarray ◽

Almost All

ABSTRACTFructophilic lactic acid bacteria (FLAB) are strongly associated with the gastrointestinal tracts (GITs) ofApis melliferaL. worker bees due to the consumption of fructose as a major carbohydrate. Seventy-seven presumptive lactic acid bacteria (LAB) were isolated from GITs of healthyA. melliferaL. adults, which were collected from 5 different geographical locations of the Apulia region of Italy. Almost all of the isolates showed fructophilic tendencies: these isolates were identified asLactobacillus kunkeei(69%) orFructobacillus fructosus(31%). A high-throughput phenotypic microarray targeting 190 carbon sources was used to determine that 83 compounds were differentially consumed. Phenotyping grouped the strains into two clusters, reflecting growth performance. The utilization of phenolic acids, such asp-coumaric, caffeic, syringic, or gallic acids, as electron acceptors was investigated in fructose-based medium. Almost all FLAB strains showed tolerance to high phenolic acid concentrations.p-Coumaric acid and caffeic acid were consumed by all FLAB strains through reductases or decarboxylases. Syringic and gallic acids were partially metabolized. The data collected suggest that FLAB require external electron acceptors to regenerate NADH. The use of phenolic acids as external electron acceptors by the 4 FLAB showing the highest phenolic acid reductase activity was investigated in glucose-based medium supplemented withp-coumaric acid. Metabolic responses observed through a phenotypic microarray suggested that FLAB may usep-coumaric acid as an external electron acceptor, enhancing glucose dissimilation but less efficiently than other external acceptors such as fructose or pyruvic acid.IMPORTANCEFructophilic lactic acid bacteria (FLAB) remain to be fully explored. This study intends to link unique biochemical features of FLAB with their habitat. The quite unique FLAB phenome within the group lactic acid bacteria (LAB) may have practical relevance in food fermentations. The FLAB phenome may have implications for the levels of hexose metabolism products in fermented foods, as well as food probiotication. Due to the harsh conditions of honeybees' GITs, these bacteria had to develop specific physiological and biochemical characteristics, such as tolerance to phenolic acids. The screening of FLAB strains based on metabolic pathways involving phenolic acids may allow the selection of starter cultures with both technological and functional beneficial attributes. Bioconversion of phenolic compounds may contribute to the aroma attributes and biofunctionality of fermented foods. Thus, the selection of FLAB strains as starter cultures with specific enzymatic activities involving phenolic acids may have a promising role in food fermentations.

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Cell Surface Polysaccharides Represent a Common Strategy for Adsorption among Phages Infecting Lactic Acid Bacteria: Lessons from Dairy Lactococci and Streptococci

mSystems ◽

10.1128/msystems.00641-21 ◽

2021 ◽

Vol 6 (4) ◽

Author(s):

Jennifer Mahony

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Cell Surface ◽

Lactococcus Lactis ◽

Streptococcus Thermophilus ◽

Starter Cultures ◽

Content Type ◽

Common Strategy ◽

Surface Polysaccharides

Food fermentations rely on the application of robust bacterial starter cultures, the majority of which are represented by members of the lactic acid bacteria including Lactococcus lactis and Streptococcus thermophilus . Bacteriophage (or phage) proliferation remains one of the most significant threats to the fermentation industry.

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Development of biotechnology for gluten-free sourdough bakery products with a new microbial composition

Khleboproducty ◽

10.32462/0235-2508-2020-29-12-59-63 ◽

2020 ◽

Vol 29 (12) ◽

pp. 59-63

Author(s):

O.I. Parakhina ◽

◽

M.N. Lokachuk ◽

L.I. Kuznetsova ◽

E.N. Pavlovskaya ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Culture ◽

Comparative Assessment ◽

Starter Cultures ◽

Bakery Products ◽

Gluten Free ◽

Microbial Composition ◽

Fermentative Activity ◽

Theoretical Foundations

The research was carried out within the framework of the theme of state assignment № 0593–2019–0008 «To develop theoretical foundations for creating composite mixtures for bakery products using physical methods of exposure that ensure homogeneity, stability of mixtures and bioavailability of nutrients, to optimize diets population of Russia». The data on the species belonging of new strains of lactic acid bacteria and yeast isolated from samples of good quality gluten-free starter cultures are presented. A comparative assessment of the antagonistic and acid-forming activity of strains of lactic acid bacteria and the fermentative activity of yeast was carried out. The composition of microbial compositions from selected strains of LAB and yeast was developed. The influence of the starter culture on the new microbial composition on the physicochemical, organoleptic indicators of the bread quality and resistance to mold and ropy-disease was investigated.

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Evaluating the technological properties of lactic acid bacteria in Wagyu cattle milk

Journal of Dairy Research ◽

10.1017/s0022029921000339 ◽

2021 ◽

pp. 1-7

Author(s):

Harutoshi Tsuda ◽

Kana Kodama

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Raw Milk ◽

Starter Cultures ◽

Technological Properties ◽

Mature Milk ◽

16S Rdna Sequence Analysis ◽

Physiological And Biochemical Characteristics ◽

Fermented Dairy Products ◽

Fermented Dairy

Abstract This paper reveals the technological properties of lactic acid bacteria isolated from raw milk (colostrum and mature milk) of Wagyu cattle raised in Okayama Prefecture, Japan. Isolates were identified based on their physiological and biochemical characteristics as well as 16S rDNA sequence analysis. Streptococcus lutetiensis and Lactobacillus plantarum showed high acid and diacetyl-acetoin production in milk after 24 h of incubation at 40 and 30°C, respectively. These strains are thought to have potential for use as starter cultures and adjunct cultures for fermented dairy products.

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Evaluation the potential of lactic acid bacteria isolates from traditional beef jerky as starter cultures and their effects on flavor formation during fermentation

LWT ◽

10.1016/j.lwt.2021.110982 ◽

2021 ◽

Vol 142 ◽

pp. 110982

Author(s):

Rongxin Wen ◽

Fangda Sun ◽

Yan Wang ◽

Qian Chen ◽

Baohua Kong

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Starter Cultures ◽

Beef Jerky

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Isolation and Characterization of Lactic Acid Bacteria and Yeasts from Typical Bulgarian Sourdoughs

Microorganisms ◽

10.3390/microorganisms9071346 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1346

Author(s):

Mariana Petkova ◽

Petya Stefanova ◽

Velitchka Gotcheva ◽

Angel Angelov

Keyword(s):

Lactic Acid ◽

Sequence Analysis ◽

Lactic Acid Bacteria ◽

Antimicrobial Properties ◽

Matter Content ◽

Starter Cultures ◽

Rrna Gene ◽

Dry Matter Content ◽

Isolation And Characterization ◽

Selection Of

Traditional sourdoughs in Bulgaria were almost extinct during the centralized food production system. However, a rapidly developing trend of sourdough revival in the country is setting the demand for increased production and use of commercial starter cultures. The selection of strains for such cultures is based on geographical specificity and beneficial technological properties. In this connection, the aim of this study was to isolate, identify and characterize lactic acid bacteria (LAB) and yeasts from typical Bulgarian sourdoughs for the selection of strains for commercial sourdough starter cultures. Twelve samples of typical Bulgarian sourdoughs were collected from different geographical locations. All samples were analyzed for pH, total titratable acidity and dry matter content. Enumeration of LAB and yeast was also carried out. Molecular identification by 16S rDNA sequence analysis was performed for 167 LAB isolates, and 106 yeast strains were identified by ITS1-5.8S-ITS2 rRNA gene partial sequence analysis. The LAB strains were characterized according to their amylolytic and proteolytic activity and acidification capacity, and 11 strains were selected for further testing of their antimicrobial properties. The strains with the most pronounced antibacterial and antifungal activity are listed as recommended candidates for the development of starter cultures for sourdoughs or other food products.

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Lactic Acid Bacteria in Cheddar Cheese Made with Sodium Chloride, Potassium Chloride or Mixtures of the Two Salts

Journal of Food Protection ◽

10.4315/0362-028x-58.1.62 ◽

1995 ◽

Vol 58 (1) ◽

pp. 62-69 ◽

Cited By ~ 14

Author(s):

K. ANJAN REDDY ◽

ELMER H. MARTH

Keyword(s):

Lactic Acid ◽

Sodium Chloride ◽

Lactic Acid Bacteria ◽

Potassium Chloride ◽

Starter Culture ◽

Cheddar Cheese ◽

Starter Cultures ◽

Detectable Effect ◽

Agar Media ◽

Cheese Curd

Three different split lots of Cheddar cheese curd were prepared with added sodium chloride (NaCl) potassium chloride (KCl) or mixtures of NaCl/KCl (2:1 1:1 1:2 and 3:4 all on wt/wt basis) to achieve a final salt concentration of 1.5 or 1.75%. At intervals during ripening at 3±1°C samples were plated with All-Purpose Tween (APT) and Lactobacillus Selection (LBS) agar. Isolates were obtained of bacteria that predominated on the agar media. In the first trial (Lactococcus lactis subsp. lactis plus L. lactis subsp. cremoris served as starter cultures) L. lactis subsp.lactis Lactobacillus casei and other lactobacilli were the predominant bacteria regardless of the salting treatment Received by the cheese. In the second trial (L. lactis subsp. lactis served as the starter culture) unclassified lactococci L. lactis subsp. lactis unclassified lactobacilli and L. casei predominated regardless of the salting treatment given the cheese. In the third trial (L. lactis subsp. cremoris served as the starter culture) unclassified lactococci unclassified lactobacilli L. casei and Pediococcus cerevisiae predominated regardless of the salting treatment applied to the cheese Thus use of KCl to replace some of the NaCl for salting cheese had no detectable effect on the kinds of lactic acid bacteria that developed in ripening Cheddar cheese.

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