An alternative method for screening lactic acid bacteria for the production of exopolysaccharides with rapid confirmation

The accumulation of exopolysaccharides (EPS) produced by microorganisms occurs in the presence of excess substrate and limiting conditions of elements that are essential to growth, such as nitrogen, phosphorus, sulfur, and magnesium. The presence of EPS produced by bacterial cells contributes to slime colonies formation in solid medium and increased viscosity in liquid medium. This paper proposes an alternative method for screening EPS-producing lactic acid bacteria using solid medium-containing discs of filter paper that are saturated with active cultures. The screening was carried out under different culture conditions varying the type of sugar, pH, and temperature. EPS production was visualized by the presence of mucoid colonies on the discs, which was confirmed by the formation of a precipitate when part of this colony was mixed with absolute alcohol. The established conditions for obtaining a high number of isolates producing EPS were 10% sucrose, pH 7.5 and 28 ºC. This method proved to be effective and economical because several strains could be tested on the same plate, with immediate confirmation.

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Effects of Feed Mixed with Lactic Acid Bacteria and Carbon, Nitrogen, Phosphorus Supplied to the Water on the Growth and Survival Rate of White Leg Shrimp (Penaeus vannamei) Infected with Acute Hepatopancreatic Necrosis Disease Caused by Vibrio parahaemolyticus

Biology ◽

10.3390/biology10040280 ◽

2021 ◽

Vol 10 (4) ◽

pp. 280

Author(s):

Linh Nguyen Thi Truc ◽

Tuu Nguyen Thanh ◽

To Tran Thi Hong ◽

Day Pham Van ◽

Minh Vo Thi Tuyet ◽

...

Keyword(s):

Lactic Acid ◽

Survival Rate ◽

Lactic Acid Bacteria ◽

Vibrio Parahaemolyticus ◽

Control Group ◽

Penaeus Vannamei ◽

Growth And Survival ◽

Acute Hepatopancreatic Necrosis Disease ◽

Nitrogen Phosphorus ◽

Shrimp Health

This study aimed to evaluate the growth, survival rate, and resistance to acute hepatopancreatic necrosis disease (AHPND) of white leg shrimp (Penaeus vannamei) by using Lactobacillus plantarum, Lactobacillus fermentum, and Pediococcus pentosaceus mixed with feed, and at the same time supplying CNP in a ratio of 15:1:0.1 to the water. As a result, the treatments that shrimp were fed with feed containing lactic acid bacteria (LAB), especially L. plantarum, have increased shrimp growth, total hemocyte cells, granulocyte cells, and hyaline cells significantly (p < 0.05) in comparison to the control group. The supply of CNP to the water has promoted the intensity of V. parahaemolyticus effects on shrimp health and significantly decreased total hemocyte cells, granulocyte cells, and hyaline cells by 30–50% in the period after three days of the challenge, except in L. plantarum treatment, which had only a 20% decrease compared to other treatments. In CNP supplying treatments, the AHPND infected rate and mortality of shrimp were higher than those in other treatments. In summary, the supply of CNP had significantly reduced the shrimp’s immune response and promoted the susceptibility of shrimp to AHPND in both cases of use with and without LAB-containing diets.

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The Inhibitory Effect of Lactobacillus acidophilus and Lactobacillus plantarum against Candida albicans Associated with Denture Stomatitis

Baghdad Science Journal ◽

10.21123/bsj.12.3.479-484 ◽

2015 ◽

Vol 12 (3) ◽

pp. 479-484

Author(s):

Baghdad Science Journal

Keyword(s):

Candida Albicans ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Lactobacillus Plantarum ◽

Lactobacillus Acidophilus ◽

Solid Medium ◽

Inhibition Zone ◽

Inhibitory Effect ◽

Denture Stomatitis ◽

Inhibition Effect

In this study Candida speices was diagnosed in 26 swab samples from patients with denture stomatitis , investigates the antagonism activity of Lactobacillus was investigated against the yeast of Candida albicans in vitro.Results revealed that The inhibition effect of Lactic Acid Bacteria against C.albicans was examined in solid medium, L.plantarum gave higher inhibition average 11mm followed by L.acidophillus with average 9 mm and, L.fermentum , L.casei with averages 7 mm. Whereas the filtrates, the highest inhibition zone were 20 and 16 mm by L. plantarum and L.acidophillus, respectively.

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Quantification of Geotrichum candidum growth in co-culture with lactic acid bacteria

Czech Journal of Food Sciences ◽

10.17221/205/2009-cjfs ◽

2010 ◽

Vol 27 (Special Issue 2) ◽

pp. 18-27 ◽

Cited By ~ 1

Author(s):

A. Hudecová ◽

Ľ. Valík ◽

D. Liptáková

Keyword(s):

Growth Rate ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Filamentous Fungus ◽

Solid Medium ◽

Fungal Growth ◽

Growth Dynamics ◽

Geotrichum Candidum ◽

Inhibitory Effect ◽

Food Mycology

The growth dynamics of filamentous fungus G. candidum was studied during the co-cultivation with the commercial lactic acid bacteria (LAB) culture Fresco. The experiments were carried out in milk and on the surface of a milk agar at the temperature ranging from 5 to 37°C. Ratkowsky model was used to describe the relationships of the fungal growth rate to the temperature during both, single and co-cultivation with LAB in milk. Simultaneous growth of LAB affected significantly the growth rate of the filamentous fungus. The growth of G. candidum was in average 39% slower in the co-culture than in the single cultivation. LAB pre-inoculated and growing in the solid medium did not show any significant inhibitory effect on the surface growth of G. candidum at all tested temperature. The precise data describing the growth of this cheese yeast-like fungus, G. candidum, may fill a gap in the field of quantitative food mycology and may be used for predicting its behavior in real conditions.

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Microbial development in distillers wet grains produced during fuel ethanol production from corn (Zea mays)

Canadian Journal of Microbiology ◽

10.1139/w07-073 ◽

2007 ◽

Vol 53 (9) ◽

pp. 1046-1052 ◽

Cited By ~ 6

Author(s):

R. Michael Lehman ◽

Kurt A. Rosentrater

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Heterotrophic Bacteria ◽

Micrococcus Luteus ◽

Phospholipid Fatty Acid ◽

Dry Mass ◽

Fuel Ethanol ◽

Fatty Acid Analysis ◽

Yeast Cells ◽

Bacterial Cells

Distillers grains are coproduced with ethanol and carbon dioxide during the production of fuel ethanol from the dry milling and fermentation of corn grain, yet there is little basic microbiological information on these materials. We undertook a replicated field study of the microbiology of distillers wet grains (DWG) over a 9 day period following their production at an industrial fuel ethanol plant. Freshly produced DWG had a pH of about 4.4, a moisture content of about 53.5% (wet mass basis), and 4 × 105 total yeast cells/g dry mass, of which about 0.1% were viable. Total bacterial cells were initially below detection limits (ca. 106 cells/g dry mass) and then were estimated to be ∼5 × 107 cells/g dry mass during the first 4 days following production. Culturable aerobic heterotrophic organisms (fungi plus bacteria) ranged between 104 and 105 CFU/g dry mass during the initial 4 day period, and lactic acid bacteria increased from 36 to 103 CFU/g dry mass over this same period. At 9 days, total viable bacteria and yeasts and (or) molds topped 108 CFU/g dry mass and lactic acid bacteria approached 106 CFU/g dry mass. Community phospholipid fatty acid analysis indicated a stable microbial community over the first 4 days of storage. Thirteen morphologically distinct isolates were recovered, of which 10 were yeasts and molds from 6 different genera, 2 were strains of the lactic-acid-producing Pediococcus pentosaceus and only one was an aerobic heterotrophic bacteria, Micrococcus luteus . The microbiology of DWG is fundamental to the assessment of spoilage, deleterious effects (e.g., toxins), or beneficial effects (e.g., probiotics) in its use as feed or in alternative applications.

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Investigation of Lactobacilli Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1040.319 ◽

2014 ◽

Vol 1040 ◽

pp. 319-322

Author(s):

E.V. Bulycheva ◽

E.I. Korotkova ◽

O.A. Voronova

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Bacterial Cells ◽

Luminescence Method

In this paper for investigation of the medicine «Lactobacterin» containing lactic acid bacteria was used luminescence method. It is shown, that spectrum of the Lactobacilli has 3 peaks from different substances. It is shown that during 2 hours the bacterial cells are alive.

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Automatic Segmentation and Classification of SEM Images of Bacteria Cells

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d9120.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 12858-12860

Keyword(s):

Image Analysis ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Automatic Segmentation ◽

Morphological Characteristics ◽

Bacterial Cells ◽

Electron Microscopic ◽

Sem Images ◽

Edge Based ◽

Watershed Method

In the field of microbiology, digital image analysis methods are receiving significant attention to automatically interpret images of bacterial cells. An automatic procedure to extract and classify images of lactic acid bacteria (LAB) is presented in this paper. Edge based watershed method with automatically generated markers were used to retain the image information at fine scales. The experiment was conducted on images containing one type of bacteria. The scanning electron microscopic (SEM) images of lactic acid bacteria (LAB) are used in this experiment. The image analysis and classification technique described in this paper is quick and simple to recognize organisms based on their morphological characteristics. The classification results indicate that routine methods for the detection, enumeration and identification of bacteria can be automated with use of direct microscopic methods

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IDENTIFIKASI MOLEKULAR BAKTERI ASAM LAKTAT Lactobacillus paracasei YANG ADA PADA LAPISAN MINYAK VCO

Jurnal Katalisator ◽

10.22216/jk.v2i2.2517 ◽

2017 ◽

Vol 2 (2) ◽

pp. 79

Author(s):

Suryani Suryani ◽

Dedi Nofiandi ◽

Husni Mukhtar ◽

Melona Siska ◽

Abdi Dharma ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Antiviral Agents ◽

Coconut Oil ◽

Pathogenic Fungi ◽

Coconut Milk ◽

Lactobacillus Paracasei ◽

Bacterial Cells ◽

Virgin Coconut Oil ◽

Biochemical Tests

Virgin Coconut Oil is an oil of coconut milk fermentation that has many uses such as can prevent HIV, because it functions as antibacterial, antifungal and antiviral. Antibacterial, antifungal and antiviral agents are found in bacteria lactic acid bacteriocin, a peptide that can destroy bacterial cells and pathogenic fungi and viral cells. The aim of this study was to identify molecularly lactic acid bacteria isolated and morphologically identified and biochemical tests, from fermented coconut milk. Apparently lactic acid bacteria is Lactobacillus paracasei strain 1.7. Virgin Coconut Oil adalah minyak dari fermentasi santan kelapa yang mempunyai banyak sekali kegunaan diantaranya dapat mencegah HIV, karena berfungsi sebagai antibakteri, antijamur dan antivirus. Zat antibakteri, antijamur dan antivirus itu terdapat pada bakteri asam laktat yaitu bakteriosin, berupa peptida yang dapat menghancurkan sel bakteri dan jamur patogen serta sel virus. Tujuan penelitian ini adalah mengidentifikasi secara molekular bakteri asam laktat yang telah diisolasi dan diidentifikasi secara morfologi dan uji – uji biokimia, dari santan yang difermentasi. Ternyata bakteri asam laktat nya adalah Laktobacillus paracasei strain 1.7.

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Understanding the cryotolerance of lactic acid bacteria using combined synchrotron infrared and fluorescence microscopies

The Analyst ◽

10.1039/c5an00654f ◽

2015 ◽

Vol 140 (17) ◽

pp. 5920-5928 ◽

Cited By ~ 14

Author(s):

Stéphanie Passot ◽

Julie Gautier ◽

Frédéric Jamme ◽

Stéphanie Cenard ◽

Paul Dumas ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Fluorescence Microscopy ◽

Physiological State ◽

Bacterial Cells ◽

Ftir Microspectroscopy ◽

Simultaneous Assessment

Combining synchrotron-FTIR microspectroscopy and fluorescence microscopy made it possible the simultaneous assessment of biochemistry and physiological state of small bacterial cells for better understanding the mechanisms of cell cryotolerance.

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Histamine-Producing Pathway Encoded on an Unstable Plasmid in Lactobacillus hilgardii 0006

Applied and Environmental Microbiology ◽

10.1128/aem.71.3.1417-1424.2005 ◽

2005 ◽

Vol 71 (3) ◽

pp. 1417-1424 ◽

Cited By ~ 116

Author(s):

Patrick M. Lucas ◽

Wout A. M. Wolken ◽

Olivier Claisse ◽

Juke S. Lolkema ◽

Aline Lonvaud-Funel

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Histidine Decarboxylase ◽

Acid Stress ◽

Culture Conditions ◽

Trna Synthetase ◽

Fermented Food ◽

Metabolic Energy ◽

Histamine Production ◽

Gene Coding

ABSTRACT Histamine production from histidine in fermented food products by lactic acid bacteria results in food spoilage and is harmful to consumers. We have isolated a histamine-producing lactic acid bacterium, Lactobacillus hilgardii strain IOEB 0006, which could retain or lose the ability to produce histamine depending on culture conditions. The hdcA gene, coding for the histidine decarboxylase of L. hilgardii IOEB 0006, was located on an 80-kb plasmid that proved to be unstable. Sequencing of the hdcA locus disclosed a four-gene cluster encoding the histidine decarboxylase, a protein of unknown function, a histidyl-tRNA synthetase, and a protein, which we named HdcP, showing similarities to integral membrane transporters driving substrate/product exchange. The gene coding for HdcP was cloned downstream of a sequence specifying a histidine tag and expressed in Lactococcus lactis. The recombinant HdcP could drive the uptake of histidine into the cell and the exchange of histidine and histamine. The combination of HdcP and the histidine decarboxylase forms a typical bacterial decarboxylation pathway that may generate metabolic energy or be involved in the acid stress response. Analyses of sequences present in databases suggest that the other two proteins have dispensable functions. These results describe for the first time the genes encoding a histamine-producing pathway and provide clues to the parsimonious distribution and the instability of histamine-producing lactic acid bacteria.

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Biofilm formation of Candida Spp. isolated from the vagina and antibiofilm activities of lactic acid bacteria on the these Candida Isolates

African Health Sciences ◽

10.4314/ahs.v20i2.12 ◽

2020 ◽

Vol 20 (2) ◽

pp. 641-648

Author(s):

Merih Kıvanç ◽

Sevda Er

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Virulence Factors ◽

Lactobacillus Acidophilus ◽

Biofilm Formation ◽

Bacterial Cells ◽

Candida Spp ◽

Plate Method ◽

Microtitration Plate ◽

Esterase Activities

Background: In this study, it was aimed to investigate the effects of bacterial cells and cell-free filtrates of Lactobacillus acidophilus 8MR7 and Lactobacillus paracasei subspecies paracasei 10MR8 on the biofilm formation of 3 Candida tropicalis, 3 C. glabrata and 12 C. albicans isolated from the vagina and identified their virulence factors. Methods: Haemolytic activities esterase activities, and phospholipase activities as virulence factors of Candida strains were determined. Biofilm formations of these isolates were determined by Congo Red agar and microtitration plate method. Anti-biofilm activities of bacterial cells and cell-free filtrates of L. acidophilus 8MR7 and L. paracasei subspecies paracasei 10MR8 on Candida isolates were determined by the microtitration plate method. Results: Bacterial cells of L. acidophilus 8MR7 and L. paracasei subspecies paracasei 10MR8 were not very effective in the in- hibition of biofilm, whereas it has been observed that the cell-free filtrates of these bacteria inhibit the formation of biofilms of Candida strains. Although the main mechanism for inhibiting the formation of Candida spp. biofilm is the competition for adhesion, it is concluded that the substances contained in the cell-free filtrates of lactic acid bacteria are also important. Conclusion: These isolates promise hope as potential bacteria that can be used for anti-adhesion purposes in health-care materials. Keywords: Lactobacillus acidophilus; L. paracesei subspecies paracesei; vagina; biofilm.

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