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Cardinali F, Botta C, Harasym J, Ferrocino I, Reale A, Boscaino F, Di Renzo T, Milanović V, Garofalo C, Rampanti G, Aquilanti L, Osimani A. Lacto-fermented garlic handcrafted in the Lower Silesia Region (Poland): Microbial diversity, morpho-textural traits, and volatile compounds. Food Res Int 2024; 188:114484. [PMID: 38823870 DOI: 10.1016/j.foodres.2024.114484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 04/29/2024] [Accepted: 05/07/2024] [Indexed: 06/03/2024]
Abstract
The aim of the present study was to provide a first characterization of lacto-fermented garlic manufactured by local small-scale artisanal producers in the Lower Silesia Region (Poland). The lacto-fermented garlic samples showed high nutritional features in terms of antioxidant activity. A total of 86 compounds, belonging to various chemical classes, were identified by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC/MS). Most of these compounds belonged to six main classes, being sulfur compounds, esters and acetates, oxygenated monoterpenes, monoterpene hydrocarbons, and alcohols. Aldehydes, acids, ketones, furans, and phenols were also identified. In the analyzed samples, counts up to 8 log cfu g-1 were observed for lactic acid bacteria. Metataxonomic analysis revealed the presence of Levilactobacillus, Lactiplantibacillus, Latilactobacillus, Secundilactobacillus, Weissella, Leuconostoc, Lactococcus, Pediococcus, and Lacticaseibacillus among the major taxa. These results were confirmed by the isolation and characterization of viable lactic acid bacteria. Indeed, the presence of the closest relatives to Lacticaseibacillus casei group, Pediococcus parvulus, Levilactobacillus brevis, Levilactobacillus parabrevis, and Lactiplantibacillus plantarum group was observed. A good acidification performance in salty garlic-based medium was observed for all the isolates that, between 8 and 15 days of fermentation, reached pH values comprised between 4 and 3.5, depending on the tested species. Of note, 15 out of the 37 lactic acid bacteria isolates (Levilactobacillus parabrevis, Pediococcus parvulus, Lactiplantibacillus plantarum group, and Lacticaseibacillus casei group) showed the presence of the hdcA gene of Gram-positive bacteria encoding for histidine decarboxylase. Furthermore, for 8 out of the 37 isolates the in-vitro exopolysaccharides production was observed. No isolate showed inhibitory activity against the three Listeria innocua strains used as surrogate for Listeria monocytogenes.
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Affiliation(s)
- Federica Cardinali
- Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy
| | - Cristian Botta
- Department of Agricultural, Forest, and Food Science, University of Turin, Largo Paolo Braccini 2, Grugliasco, Torino, Italy
| | - Joanna Harasym
- Department of Biotechnology and Food Analysis, Wroclaw University of Economics and Business, Komandorska 118/120, 53-345 Wrocław, Poland
| | - Ilario Ferrocino
- Department of Agricultural, Forest, and Food Science, University of Turin, Largo Paolo Braccini 2, Grugliasco, Torino, Italy
| | - Anna Reale
- Istituto di Scienze dell'Alimentazione, Consiglio Nazionale delle Ricerche, Via Roma 64, 83100 Avellino, Italy
| | - Floriana Boscaino
- Istituto di Scienze dell'Alimentazione, Consiglio Nazionale delle Ricerche, Via Roma 64, 83100 Avellino, Italy
| | - Tiziana Di Renzo
- Istituto di Scienze dell'Alimentazione, Consiglio Nazionale delle Ricerche, Via Roma 64, 83100 Avellino, Italy
| | - Vesna Milanović
- Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy
| | - Cristiana Garofalo
- Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy
| | - Giorgia Rampanti
- Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy
| | - Lucia Aquilanti
- Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy
| | - Andrea Osimani
- Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, Università Politecnica delle Marche, via Brecce Bianche, 60131 Ancona, Italy; Istituto di Scienze dell'Alimentazione, Consiglio Nazionale delle Ricerche, Via Roma 64, 83100 Avellino, Italy.
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Borowska M, Ispiryan L, Neylon E, Sahin AW, Murphy CP, Zannini E, Arendt EK, Coffey A. Screening and Application of Novel Homofermentative Lactic Acid Bacteria Results in Low-FODMAP Whole-Wheat Bread. FERMENTATION-BASEL 2023. [DOI: 10.3390/fermentation9040336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
FODMAPs are fermentable oligo-, di-, monosaccharides, and polyols. The application of homofermentative lactic acid bacteria (LAB) has been investigated as a promising approach for producing low-FODMAP whole-wheat bread. The low-FODMAP diet is recommended to treat irritable bowel syndrome (IBS). Wheat flour is staple to many diets and is a significant source of fructans, which are considered FODMAPs. The reduction of fructans via sourdough fermentation, generally associated with heterofermentative lactic acid bacteria (LAB), often leads to the accumulation of other FODMAPs. A collection of 244 wild-type LAB strains was isolated from different environments and their specific FODMAP utilisation profiles established. Three homofermentative strains were selected for production of whole-wheat sourdough bread. These were Lactiplantibacillus plantarum FST1.7 (FST1.7), Lacticaseibacillus paracasei R3 (R3), and Pediococcus pentosaceus RYE106 (RYE106). Carbohydrate levels in flour, sourdoughs (before and after 48 h fermentation), and resulting breads were analysed via HPAEC-PAD and compared with whole-wheat bread leavened with baker’s yeast. While strain R3 was the most efficient in FODMAP reduction, breads produced with all three test strains had FODMAP content below cut-off levels that would trigger IBS symptoms. Results of this study highlighted the potential of homofermentative LAB in producing low-FODMAP whole-wheat bread.
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Wang CH, Xiong WP, Huang C, Li XM, Wang QY, Huang RB. Engineering better catalytic activity and acidic adaptation into Kluyveromyces marxianus exoinulinase using site-directed mutagenesis. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:2472-2482. [PMID: 33034040 DOI: 10.1002/jsfa.10873] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 10/03/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Exoinulinase catalyzes the successive removal of individual fructose moiety from the non-reducing end of the inulin molecule, which is useful for biotechnological applications like producing fructan-based non-grain biomass energy and high-fructose syrup. In this study, an exoinulinase (KmINU) from Kluyveromyces marxianus DSM 5418 was tailored for increased catalytic activity and acidic adaptation for inulin hydrolysis processes by rational site-directed mutagenesis. RESULTS Three mutations, S124Y, N158S and Q215V distal to the catalytic residues of KmINU were designed and heterologously expressed in Pichia pastoris GS115. Compared to the wild-type, S124Y shifted the pH-activity profile towards acidic pH values and increased the catalytic activity and catalytic efficiency by 59% and 99% to 688.4 ± 17.03 s-1 and 568.93 L mmol-1 s-1 , respectively. N158S improved the catalytic activity under acidic pH conditions, giving a maximum value of 464.06 ± 14.06 s-1 on inulin at pH 4.5. Q215V markedly improved the substrate preference for inulin over sucrose by 5.56-fold, and showed catalytic efficiencies of 208.82 and 6.88 L mmol-1 s-1 towards inulin and sucrose, respectively. Molecular modeling and computational docking indicated that structural reorientation may underlie the increased catalytic activity, acidic adaptation and substrate preference. CONCLUSIONS The KmINU mutants may serve as industrially promising candidates for inulin hydrolysis. Protein engineering of exoinulinase here provides a successful example of the extent to which mutating non-conserved substrate recognition and binding residues distal to the active site can be used for industrial enzyme improvements. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Cheng-Hua Wang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Wu-Ping Xiong
- College of Life Science and Technology, Guangxi University, Nanning, China
| | - Cheng Huang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, China
| | - Xiao-Ming Li
- Nanning Sinozyme Biotechnology Co., Ltd, Nanning, China
| | - Qing-Yan Wang
- State Key Laboratory of Non-Food Biomass and Enzyme Technology, National Engineering Research Center for Non-food Biorefinery, Guangxi Key Laboratory of Biorefinery, Guangxi Academy of Sciences, Nanning, China
| | - Ri-Bo Huang
- College of Life Science and Technology, Guangxi University, Nanning, China
- State Key Laboratory of Non-Food Biomass and Enzyme Technology, National Engineering Research Center for Non-food Biorefinery, Guangxi Key Laboratory of Biorefinery, Guangxi Academy of Sciences, Nanning, China
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Bechtner J, Ludwig C, Kiening M, Jakob F, Vogel RF. Living the Sweet Life: How Liquorilactobacillus hordei TMW 1.1822 Changes Its Behavior in the Presence of Sucrose in Comparison to Glucose. Foods 2020; 9:foods9091150. [PMID: 32825547 PMCID: PMC7555045 DOI: 10.3390/foods9091150] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 08/14/2020] [Accepted: 08/17/2020] [Indexed: 12/12/2022] Open
Abstract
Liquorilactobacillus (L.) hordei (formerly Lactobacillus hordei) is one of the dominating lactic acid bacteria within the water kefir consortium, being highly adapted to survive in this environment, while producing high molecular weight dextrans from sucrose. In this work, we extensively studied the physiological response of L. hordei TMW 1.1822 to sucrose compared to glucose, applying label-free, quantitative proteomics of cell lysates and exoproteomes. This revealed the differential expression of 53 proteins within cellular proteomes, mostly associated with carbohydrate uptake and metabolism. Supported by growth experiments, this suggests that L. hordei TMW 1.1822 favors fructose over other sugars. The dextransucrase was expressed irrespectively of the present carbon source, while it was significantly more released in the presence of sucrose (log2FC = 3.09), being among the most abundant proteins within exoproteomes of sucrose-treated cells. Still, L. hordei TMW 1.1822 expressed other sucrose active enzymes, predictively competing with the dextransucrase reaction. While osmolysis appeared to be unlikely, sucrose led to increased release of a multitude of cytoplasmic proteins, suggesting that biofilm formation in L. hordei is not only composed of a polysaccharide matrix but is also of proteinaceous nature. Therefore, our study highlights the intrinsic adaptation of water kefir-borne L. hordei to sucrose-rich habitats and provides fundamental knowledge for its use as a starter culture in plant-based food fermentations with in situ dextran formation.
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Affiliation(s)
- Julia Bechtner
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München (TUM), 85354 Freising, Germany; (J.B.); (F.J.)
| | - Christina Ludwig
- Bavarian Center for Biomolecular Mass Spectrometry (BayBioMS), 85354 Freising, Germany;
| | - Michael Kiening
- Lehrstuhl für Genomorientierte Bioinformatik, Technische Universität München (TUM), 85354 Freising, Germany;
| | - Frank Jakob
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München (TUM), 85354 Freising, Germany; (J.B.); (F.J.)
| | - Rudi F. Vogel
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München (TUM), 85354 Freising, Germany; (J.B.); (F.J.)
- Correspondence:
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Li Q, Loponen J, Gänzle MG. Characterization of the Extracellular Fructanase FruA in Lactobacillus crispatus and Its Contribution to Fructan Hydrolysis in Breadmaking. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:8637-8647. [PMID: 32687341 DOI: 10.1021/acs.jafc.0c02313] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) trigger symptoms of irritable bowel syndrome (IBS). Fructan degradation during bread making reduces FODMAPs in bread while maintaining the content of dietary fiber. This study explored the presence of the fructanases FruA in lactobacilli and characterized its use in bread making. FruA was exclusively present in vertebrate-adapted lactobacilli. In Lactobacillus crispatus DSM29598, FruA was located in cell wall fractions and includes a SLAP domain. FruA hydrolyzed levan or inulin; expression of fruA was not subject to catabolite repression. Fructans in bread were reduced by less than 50% in a straight dough process; conventional sourdough fermentation reduced fructans in bread by 65-70%. Sourdough fermentation with L. crispatus reduced fructans in bread by more than 90%. In conclusion, reduction of FODMAP by sourdough fermentation may improve tolerance in many IBS patients. Fermentation with FruA-expressing L. crispatus DSM29598 produces a low FODMAP bread.
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Affiliation(s)
- Qing Li
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
| | | | - Michael G Gänzle
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta T6G 2P5, Canada
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Martinez-Gutierrez F, Ratering S, Juárez-Flores B, Godinez-Hernandez C, Geissler-Plaum R, Prell F, Zorn H, Czermak P, Schnell S. Potential use of Agave salmiana as a prebiotic that stimulates the growth of probiotic bacteria. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2017.05.044] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Castro-Zavala A, Juárez-Flores BI, Pinos-Rodríguez JM, Delgado-Portales RE, Aguirre-Rivera JR, Alcocer-Gouyonnet F. Prebiotic Effects of Agave salmiana Fructans in Lactobacillus acidophilus and Bifidobacterium lactis Cultures. Nat Prod Commun 2015. [DOI: 10.1177/1934578x1501001145] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Agave salmiana is a fructan rich species that is widely distributed in Mexico. The aim of this investigation was to extract the fructans of A. salmiana and evaluate their prebiotic effect in 48 hours in vitro cultures of Bifidobacterium lactis and Lactobacillus acidophilus and to compare this effect with other available fructan sources. A significant difference in pH, optical density and biomass was found in the cultures depending on the source of fructans and the type of bacteria. It was possible to determine a dose-response effect of the A. salmiana fructans and the growth of the studied strains.
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Affiliation(s)
| | | | | | | | | | - Francisco Alcocer-Gouyonnet
- Facultad de Medicina; Universidad Autónoma de San Luis Potosí. km 14.5 Carretera San Luis Potosí – Matehuala, ejido Palma de la Cruz, Soledad de Graciano Sánchez, S.L.P. 78321, México
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Goh YJ, Klaenhammer TR. Genetic Mechanisms of Prebiotic Oligosaccharide Metabolism in Probiotic Microbes. Annu Rev Food Sci Technol 2015; 6:137-56. [DOI: 10.1146/annurev-food-022814-015706] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Yong Jun Goh
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, North Carolina 27695; ,
| | - Todd R. Klaenhammer
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, North Carolina 27695; ,
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Chen C, Zhou F, Ren J, Ai L, Dong Y, Wu Z, Liu Z, Chen W, Guo B. Cloning, expression and functional validation of a β-fructofuranosidase from Lactobacillus plantarum. Process Biochem 2014. [DOI: 10.1016/j.procbio.2014.02.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yıldız S. The Metabolism of Fructooligosaccharides and Fructooligosaccharide-Related Compounds in Plants. FOOD REVIEWS INTERNATIONAL 2010. [DOI: 10.1080/87559129.2010.518295] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- S. Yıldız
- a Süleyman Demirel University, Chemical Engineering Department , Çünür , Isparta , Turkey
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Goh YJ, Lee JH, Hutkins RW. Functional analysis of the fructooligosaccharide utilization operon in Lactobacillus paracasei 1195. Appl Environ Microbiol 2007; 73:5716-24. [PMID: 17644636 PMCID: PMC2074902 DOI: 10.1128/aem.00805-07] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The fosABCDXE operon encodes components of a putative fructose/mannose phosphoenolpyruvate-dependent phosphotransferase system and a beta-fructosidase precursor (FosE) that are involved in the fructooligosaccharide (FOS) utilization pathway of Lactobacillus paracasei 1195. The presence of an N-terminal signal peptide sequence and an LPQAG cell wall anchor motif in the C-terminal region of the deduced FosE precursor amino acid sequence predicted that the enzyme is cell wall associated, indicating that FOS may be hydrolyzed extracellularly. In this study, cell fractionation experiments demonstrated that the FOS hydrolysis activity was present exclusively in the cell wall extract of L. paracasei previously grown on FOS. In contrast, no measurable FOS hydrolysis activity was detected in the cell wall extract from the isogenic fosE mutant. Induction of beta-fructosidase activity was observed when cells were grown on FOS, inulin, sucrose, or fructose but not when cells were grown on glucose. A diauxic growth pattern was observed when cells were grown on FOS in the presence of limiting glucose (0.1%). Analysis of the culture supernatant revealed that glucose was consumed first, followed by the longer-chain FOS species. Transcription analysis further showed that the fos operon was expressed only after glucose was depleted in the medium. Expression of fosE in a non-FOS-fermenting strain, Lactobacillus rhamnosus GG, enabled the recombinant strain to metabolize FOS, inulin, sucrose, and levan.
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Affiliation(s)
- Yong Jun Goh
- University of Nebraska, Department of Food Science and Technology, 338 FIC, Lincoln, NE 68583-0919, USA
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Goh YJ, Zhang C, Benson AK, Schlegel V, Lee JH, Hutkins RW. Identification of a putative operon involved in fructooligosaccharide utilization by Lactobacillus paracasei. Appl Environ Microbiol 2006; 72:7518-30. [PMID: 17028235 PMCID: PMC1694223 DOI: 10.1128/aem.00877-06] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The growth and activity of some Lactobacillus and Bifidobacterium strains are stimulated by the presence of nondigestible fructooligosaccharides (FOS), which are selectively fermented by specific intestinal bacteria. Consumption of FOS, therefore, enriches for those bacteria that possess metabolic pathways necessary for FOS metabolism. In this study, a DNA microarray consisting of 7,680 random genomic library fragments of Lactobacillus paracasei 1195 was used to examine genes involved in the utilization of FOS in this organism. Differential expression profiles between cells grown on FOS and those grown on glucose provided a basis for identifying genes specifically induced by FOS. Several of the FOS-induced genes shared sequence identity with genes encoding beta-fructosidases and components of phosphoenolpyruvate-dependent phosphotransferase systems (PTS). These genes were organized in a putative operon, designated the fos operon, that may play an essential role in FOS utilization. The complete 7,631-bp nucleotide sequence of the putative fos operon was determined and consists of fosABCDXE genes, which encode a putative fructose/mannose PTS (FosABCDX) and a beta-fructosidase precursor (FosE). The latter contains an N-terminal signal peptide sequence and cell wall sorting signals at the C-terminal region, suggesting its localization at the cell wall. Inactivation of the fosE gene led to impaired growth on FOS and other beta-fructose-linked carbohydrates. Transcriptional analysis by reverse transcriptase PCR suggested that fosABCDXE was cotranscribed as a single mRNA during growth on FOS. Expression array analysis revealed that when glucose was added to FOS-grown cells, transcription of the FOS-induced genes was repressed, indicating that FOS metabolism is subject to catabolite regulation.
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Affiliation(s)
- Yong Jun Goh
- Department of Food Science and Technology, University of Nebraska, 338 FIC, Lincoln, NE 68583-0919, USA
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Sánchez JI, Martínez B, Guillén R, Jiménez-Díaz R, Rodríguez A. Culture conditions determine the balance between two different exopolysaccharides produced by Lactobacillus pentosus LPS26. Appl Environ Microbiol 2006; 72:7495-502. [PMID: 17012595 PMCID: PMC1694222 DOI: 10.1128/aem.01078-06] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lactobacillus pentosus LPS26, isolated from a natural fermentation of green olives, produces a capsular polymer constituted of two exopolysaccharides (EPS): EPS A, a high-molecular-weight (high-Mw) polysaccharide (1.9x10(6) Da) composed of glucose and rhamnose (3:1), and EPS B, a low-Mw polysaccharide (3.3x10(4) Da) composed of glucose and mannose (3:1). Fermentation experiments in a chemically semidefined medium with different carbon sources (glucose, fructose, mannitol, and lactose) showed that all of them except fructose supported EPS A production rather than EPS B production. The influence of temperature and pH was further analyzed. As the temperature dropped, increased synthesis of both EPS was detected. The control of pH especially enhanced EPS B production. With regard to this, the maximum total EPS production (514 mg liter-1) was achieved at a suboptimal growth temperature (20 degrees C) and pH 6.0. Continuous cultures showed that EPS A, synthesized mainly at low dilution rates, is clearly dependent on the growth rate, whereas EPS B synthesis was hardly affected. EPS production was also detected in supplemented skimmed milk, but no increase on the viscosity of the fermented milk was recorded. This could be linked to the high proportion of the low-Mw polysaccharide produced in these conditions in contrast to that observed in culture media. Overall, the present study shows that culture conditions have a clear impact on the type and concentration of EPS produced by strain LPS26, and consequently, these conditions should be carefully selected for optimization and application studies. Finally, it should be noted that this is, to our knowledge, the first report on EPS production by L. pentosus.
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Affiliation(s)
- Jorge-Ignacio Sánchez
- Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Ctra. Infiesto s/n, 33300 Villaviciosa, Spain
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