Suppression of lactate production by using sucrose as a carbon source in lactic acid bacteria

Lactobacillus plantarum N014 is a bacteriocin-producing lactic acid bacteria originally isolated from nham, a traditional Thai fermented sausage, and in the process of development to be used as a starter culture for nham fermentation. During the fermentation process, there is a need to identify the starter culture among several naturally occurring bacteria. In this study, a new plasmid carrying the gfp (green fluorescent protein) gene was constructed based on pGKV210, an Escherichia coli/Lactococcus shuttle vector containing an erythromycin resistance marker. The gfp gene derived from pGFPuv was placed under the control of an L-lactate dehydrogenase promoter and then inserted at the EcoRI site of pGKV210, leading to pN014-GFP. The novel plasmid was used to transform L. plantarum N014, which is a bacteriocin-producing lactic acid bacteria isolated from nham. The resulting transformant, L. plantarum N014-GFP+, was brightly fluorescent and harbored the expected plasmid. A plasmid stability test revealed that pN014-GFP was stable after 100 generations of growth under nonselective pressure. L. plantarum N014-GFP+ and its parent strain were shown to be very similar in growth rate, bacteriocin production, and lactate production. L. plantarum N014-GFP+ was able to survive in a nham model. The survival clones were still fluorescent and harbored pN014-GFP.

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Two-species community design of Lactic Acid Bacteria for optimal production of Lactate

10.1101/2020.10.24.353805 ◽

2020 ◽

Author(s):

Maziya Ibrahim ◽

Karthik Raman

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

In Silico ◽

Raw Materials ◽

Experimental Testing ◽

Lactate Production ◽

Optimal Production ◽

Multiple Substrates ◽

Balance Analysis ◽

Optimisation Methods

AbstractMicrobial communities that metabolise pentose and hexose sugars are useful in producing high-value chemicals, as this can result in the effective conversion of raw materials to the product, a reduction in the production cost, and increased yield. Here, we present a computational approach called CAMP (Co-culture/Community Analyses for Metabolite Production) that simulates and identifies appropriate communities to produce a metabolite of interest. To demonstrate this approach, we focus on optimal production of lactate from various Lactic Acid Bacteria. We used genome-scale metabolic models (GSMMs) belonging to Lactobacillus, Leuconostoc, and Pediococcus species from the Virtual Metabolic Human (VMH; https://vmh.life/) resource and well-curated GSMMs of L. plantarum WCSF1 and L. reuteri JCM 1112. We studied 1176 two-species communities using a constraint-based modelling method for steady-state flux-balance analysis of communities. Flux variability analysis was used to detect the maximum lactate flux in a community. Using glucose or xylose as substrates separately or in combination resulted in either parasitism, amensalism, or mutualism being the dominant interaction behaviour in the communities. Interaction behaviour between members of the community was deduced based on variations in the predicted growth rates of monocultures and co-cultures. Acetaldehyde, ethanol, NH4+, among other metabolites, were found to be cross-fed between community members. L. plantarum WCSF1 was a member of communities with high lactate yields. In silico community optimisation strategies to predict reaction knock-outs for improving lactate flux were implemented. Reaction knock-outs of acetate kinase, phosphate acetyltransferase, and fumarate reductase in the communities were found to enhance lactate production.ImportanceUnderstanding compatibility and interactions based on growth between the members of a microbial community is imperative to exploit these communities for biotechnological applications. Towards this goal, here, we introduce a computational analysis framework that evaluates all possible two-species communities generated from a given set of microbial species on single or multiple substrates to achieve optimal production of a target metabolite. As a case study, we analysed communities of Lactic Acid Bacteria to produce lactate. Lactate is a platform chemical produced experimentally from lignocellulosic biomass, which constitutes pentoses and hexoses, such as xylose and glucose. Metabolic engineering strategies, such as reaction knock-outs that can improve product flux while retaining the community’s viability are identified using in silico optimisation methods. Our approach can guide in the selection of most promising communities for experimental testing and validation to produce valuable bio-based chemicals.

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Karakterisasi Bakteri Asam Laktat Amilolitik dari Industri Pengolahan Pati Sagu

Jurnal Agritech ◽

10.22146/agritech.17014 ◽

2017 ◽

Vol 37 (1) ◽

pp. 96 ◽

Cited By ~ 1

Author(s):

Yusmarini Yusmarini ◽

Usman Pato ◽

Vonny Setiaries Johan ◽

Akhyar Ali ◽

Kusumaningrum Kusumaningrum

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Carbon Source ◽

Lactobacillus Plantarum ◽

Morphological Identification ◽

Sago Starch ◽

Gram Positive ◽

Processing Industry ◽

Gram Positive Bacteria ◽

Amylolytic Lactic Acid Bacteria

Amylolytic lactic acid bacteria are a group of bacteria that are capable to use starch as the carbon source. The objectives of this research were to characterize, and identify the lactic acid bacteria from sago starch processing industry, which might be used to modify the sago starch. There were 39 isolates isolated from sago processing industry, and 36 of them were presumed as lactic acid bacteria. From 36 isolates suspected as lactic acid bacteria, 9 of them had amylolytic properties. Morphological identification results show that the 9 isolates were l Gram-positive bacteria, negative catalase, rod shape, and 5 isolates produced gas, while 4 isolates did not produce gas. The ability to produce amylase varied among isolates and isolate RN2.12112 had the higher amylolytic ability than others. Results show that the nine isolates identified as lactic acid bacteria were dominated by Lactobacillus plantarum 1. ABSTRAKBakteri asam laktat (BAL) yang bersifat amilolitik adalah bakteri asam laktat yang mampu memanfaatkan pati sebagai substratnya. Tujuan penelitian adalah untuk mengkarakterisasi sifat amilolitik dan mengidentifikasi bakteri asam laktat yang mempunyai kemampuan amilolitik untuk memodifikasi pati sagu. Hasil penelitian memperoleh 39 isolat dari industri pengolahan sagu dan 36 diantaranya diduga sebagai bakteri asam laktat. Sembilan dari 36 isolat yang diduga bakteri asam laktat mempunyai sifat amilolitik. Sembilan isolat yang bersifat amilolitik selanjutnya diidentifikasi secara morfologi yang meliputi pewarnaan Gram, bentuk sel, uji katalase, dan uji kemampuan fermentasi. Hasil identifikasi secara morfologi menunjukkan bahwa kesembilan isolat termasuk kelompok bakteri Gram positif, katalase negatif, bentuk basil, dan lima isolat menghasilkan gas sedangkan empat isolat tidak menghasilkan gas. Kemampuan isolat untuk menghasilkan amilase bervariasi dan isolat RN2.12112 mempunyai kemampuan amilolitik lebih tinggi dibanding isolat lainnya. Hasil identifikasi menunjukkan bahwa dari sembilan isolat yang diidentifikasi didominasi oleh Lactobacillus plantarum 1.

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Fascinating fructophilic lactic acid bacteria associated with various fructose-rich niches

Annales Universitatis Mariae Curie-Sklodowska sectio C – Biologia ◽

10.17951/c.2017.72.2.41-50 ◽

2019 ◽

Vol 72 (2) ◽

pp. 41

Author(s):

Artur Pachla ◽

Aneta A. Ptaszyńska ◽

Magdalena Wicha ◽

Ewa Oleńska ◽

Wanda Małek

Keyword(s):

Wound Healing ◽

Acetic Acid ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Carbon Source ◽

End Products ◽

Therapeutic Properties ◽

Acid Produce ◽

Biochemical Features

<p>Fructophilic lactic acid bacteria (FLAB) are recently described group of lactic acid bacteria (LAB) that prefer fructose instead of glucose as a carbon source. FLAB have been isolated from fructose-rich niches such as flowers, fruits, fermented fruits, and gastrointestinal tracts of insects whose diet is based on fructose. These bacteria are divided into obligate and facultative fructophilc lactobacilli based on biochemical features. All FLAB are heterofermentative microorganisms, which during fermentation of carbohydrates, in addition to lactic acid, produce also acetic acid, and alcohol as end-products. The fructophilic bacteria, inhabiting the honeybee guts positively impact the health of their hosts, improve their longevity, and are promising probiotic candidates. These symbionts of honeybees play a key role in the production of honey by bees and are present in a large number in fresh honey. The combination of osmolarity with antibacterial, and therapeutic properties of these bacteria make fresh honey optimal alternative for future wound healing.</p>

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Inhibition of Botulinum Toxin Formation in Bacon by Acid Development

Journal of Food Protection ◽

10.4315/0362-028x-43.6.450 ◽

1980 ◽

Vol 43 (6) ◽

pp. 450-457 ◽

Cited By ~ 46

Author(s):

N. TANAKA ◽

E. TRAISMAN ◽

M. H. LEE ◽

R. G. CASSENS ◽

E. M. FOSTER

Keyword(s):

Lactic Acid ◽

Botulinum Toxin ◽

Lactic Acid Bacteria ◽

Carbon Source ◽

Lactobacillus Plantarum ◽

Sodium Nitrite ◽

Clostridium Botulinum ◽

Protective Properties ◽

Adequate Amount ◽

Toxin Formation

Lactobacillus plantarum, as a producer of lactic acid, and sucrose as a fermentable carbohydrate were evaluated for use in lowering the amount of or eliminating sodium nitrite in bacon. This work was limited to effect on antibotulinal properties. Organoleptic effects were not considered. Slices of bacon were inoculated with spores of Clostridium botulinum types A and B with or without simultaneous inoculation with a culture of L. plantarum, vacuum-packaged and incubated at 27 C. Samples were taken after various periods of incubation and assayed for botulinal toxin. We found that (a) sodium nitrite alone, at 120 ppm, did not give bacon extended protection against development of botulinum toxin if a fermentable carbon source (sucrose in these instances) was not present; (b) without added lactic acid bacteria, the effectiveness of 120 ppm of sodium nitrite plus sugar was variable and depended upon growth of naturally contaminating bacteria and (c) lactic acid bacteria with an adequate amount of sucrose gave good protection against development of botulinal toxin. Upon temperature abuse, acid was produced and growth of C. botulinum was inhibited. Because the protective properties against development of botulinal toxin in the sugar-lactic acid bacteria system were not dependent on the presence of nitrite, nitrite can be lowered to the level necessary to make organoleptically acceptable products without sacrificing safety, thus less nitrosamine formation may be achieved.

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KAJIAN ISOLAT BAKTERI ASAM LAKTAT DALAM MENURUNKAN KOLESTEROL SECARA IN VITRO DENGAN KEBERADAAN OLIGOSAKARIDA (A Study In Vitro of Lactic Acid Bacteria (LAB) Isolates on Cholesterol Lowering Ability in The Presence of Oligosaccharides)

Jurnal Agritech ◽

10.22146/agritech.12865 ◽

2016 ◽

Vol 36 (02) ◽

pp. 196 ◽

Cited By ~ 3

Author(s):

Yati Maryati ◽

Lilis Nuraida ◽

Ratih Dewanti Hariyadi

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Carbon Source ◽

Cell Surface ◽

Lactobacillus Plantarum ◽

Lactobacillus Acidophilus ◽

Lactobacillus Rhamnosus ◽

Cholesterol Reduction ◽

Cholesterol Binding

This work evaluated the abilities of five isolates of lactic acid bacteria (LAB) from different sources, i.e Lactobacillus fermentum S21209 and Lactobacillus plantarum 1-S27202 from tempe, Lactobacillus rhamnosus R23 and Pediococcus pentosaceus 1-A38 from human breast milk and a commercially available human isolates Lactobacillus acidophilus FNCC0051 in lowering cholesterol by in vitro and metabolizing the prebiotic oligosaccharide compounds. The effects of oligosaccharide compounds on the performance of the LAB isolates in lowering cholesterol were also evaluated. The tests were done in MRS based medium in vitro with or without oligosaccharides i.e. galactooligosacharrides (GOS), fructooligosaccharides (FOS), inulin, hydrolyzed inulin or combination of oligosaccharides as prebiotics. The results revealed that all isolates were able to reduce cholesterol in the medium, and the highest cholesterol reduction was observed for L. acidophilus FNCC0051 and L. rhamnosus R23. There are two different mechanism in the loweringof cholesterol; cholesterol assimilation and cholesterol binding on the cell surface. For the case of P. pentosaceus 1-A38, it involves the assimilation, while the other four isolates may involve cholesterol binding on the cell surface. In addition, the tested LAB’s has different ability to use prebiotics, as shown by the reduction of total sugar in the medium. Oligosaccharides metabolism by L. acidophilus FNCC0051 and L. rhamnosus R23 resulted in several organic acid and SCFA with lactic acid produced as the largest proportion followed by acetic acid. Furthermore, the proportion of propionic and butyric acids were influenced by the type of isolates and carbon source. L. acidophilus FNCC 0051 was able to reduce cholesterol in the MRS based medium with oligosaccharides and their combination as carbon source and cholesterol reducing ability seems to involve both assimilation and cholesterol binding on the cell surface.Keywords: Lactic acid bacteria (LAB), oligosaccharides, synbiotic, cholesterol reduction, prebioticsABSTRAKPenelitian ini mengevaluasi lima isolat bakteri asam laktat (BAL) dari sumber yang berbeda, yaitu Lactobacillus fermentum S21209 dan Lactobacillus plantarum 1-S27202 dari tempe, Lactobacillus rhamnosus R23 dan Pediococcus pentosaceus 1-A38 dari ASI dan isolat komersial Lactobacillus acidophilus FNCC 0051 dari percernaan manusia dalam kemampuannya menurunkan kolesterol secara in vitro dan kemampuannya memetabolisme senyawa oligosakarida prebiotik. Pengaruh senyawa oligosakarida terhadap kemampuan isolat BAL terpilih untuk menurunkan kolesterol juga dievaluasi. Pengujian dilakukan pada media berbasis MRS dengan atau tanpa oligosakarida terdiri dari galaktooligosakarida (GOS), fruktooligosakarida (FOS), inulin, hidrolisat inulin atau kombinasi oligosakarida sebagai prebiotik. Hasil penelitian menunjukkan bahwa semua isolat mampu menurunkan kolesterol, dan penurunan kolesterol tertinggi ditunjukkan oleh isolat L. acidophilus FNCC0051 dan L. rhamnosus R23. Penurunan kolesterol diduga terjadi melalui dua cara yang berbeda. Mekanisme penurunan kolesterol oleh isolat P. pentosaceus 1-A38 melibatkan asimilasi kolesterol, sedangkan pada keempat isolat lainnya kemungkinan melibatkan pengikatan kolesterol pada permukaan sel. Selain itu, isolat BAL juga memiliki kemampuan yang berbeda dalam memanfaatkan oligosakarida prebiotik, terlihat pada penurunan total gula dalam medium. Metabolisme senyawa oligosakarida oleh L. acidophilus FNCC0051 dan L. rhamnosus R23 menghasilkan beberapa asam organik termasuk SCFA dengan proporsi terbesar asam laktat diikuti oleh asam asetat. Selain itu, proporsi asam propionat dan butirat dipengaruhi oleh jenis isolat dan sumber karbon. L. acidophilus FNCC 0051 mampu menurunkan kolesterol dalam media berbasis MRS dengan keberadaan oligosakarida baik tunggal maupun kombinasi sebagai sumber karbon dan melibatkan mekanisme baik asimilasi dan pengikatan kolesterol pada permukaan sel.Kata kunci: Bakteri asam laktat (BAL), oligosakarida, sinbiotik, penurunan kolesterol, prebiotik

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