Bacteria Lactobacillus Acidophilus Research Articles

Detoxification of Aflatoxin M1 (AFM1) in Dairy Base Beverages (Acidophilus Milk) by Using Different Types of Lactic Acid Bacteria-Mini Review

During the last century, notable attention has been sporadically directed on health benefits derived from consumption of milk products such as acidophilus milk. The tangy flavor and thickened texture of acidophilus milk can be correlated to added Lactobacillus acidophilus bacteria. Aflatoxin M1 (AFM1) is the result of secondary metabolites of different fungal strains. Because of the important role of dairy products in human life, especially children, a huge concern raised regarding the presence of AFM1 in consumed products. Due to serious threats to both human health and economics in all societies, the control of AFM1 is crucial. However, several physical or chemical detoxification methods were developed to removing or inactivating of AFM1, nowadays customers prefer to consume the products with lowest changes in composition as well as highest level of nutrient value. In this context, biological methods can be considered as one of the possible alternatives for conventional detoxification methods. Recently, the application of Lactic Acid Bacteria (LAB) for the reduction of AFM1 by approaching of produced metabolites and binding of AFM1 with LAB was introduced. The major aim of this present review is to highlight the feasibility of using LAB (Streptococcus thermophilus, Streptococcus bulgaricus Lactobacillus bulgaricus, Lactobacillus helviticus, Lactobacillus plantarum, Lactococcus spp.) in order remove the AFM1 from one kind of dairy base beverages (Acidophilus milk). Keywords: Aflatoxin M1, acidophilus milk, lactic acid bacteria, detoxification, binding, biological method.

The effect of probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium lactis) on the accumulation of lead in rat brains.

Lead is a toxic metal present in different concentrations in a wide variety of food products. Exposure to lead, even to low levels, causes acute and chronic toxicities. Lead can cross the blood-brain barrier and accumulate in the nervous system. Probiotics are live microorganisms that, when used in adequate amounts, confer a health benefit on the host. Although a recent study demonstrated that the studied bacteria have a protective effect against acute lead toxicity, no research has been found that shows the long-term impact of these bacteria in vivo. The current study surveyed the protective effects of two species of probiotics, Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12, that are most widely used in many functional foods against oral lead exposure (4weeks) in rat brains. The results revealed that, at the end of the second week of chronic exposure to lead and probiotic bacteria, the lowest level of lead belonged to the Lactobacillus group. At the end of the fourth week, the lowest amount of lead was related to the group receiving both types of probiotics. With the physiological benefits of probiotic consumption, the bacterial solution in this study did not show high efficacy in reducing brain lead concentrations.

Design of a potentially prebiotic and responsive encapsulation material for probiotic bacteria based on chitosan and sulfated β-glucan

HypothesisChitosan and sulfated oat β-glucan are materials suitable to create a prebiotic coating for targeted delivery to gastrointestinal system, using the layer by layer technology. ExperimentQuartz crystal microbalance with dissipation (QCM-D), spectroscopic ellipsometry (SE) and atomic force microscopy (AFM) were used to assess the multilayer formation capacity and characterize the resulting coatings in terms of morphology and material properties such as structure and rigidity. The coating of colloidal materials was proven, specifically on L. acidophilus bacteria as measured by changes in the bacterial suspension zeta potential. Viability of coated cells was shown using plate counting method. The coatings on solid surfaces were examined after exposure to mimics of gastrointestinal fluids and a commercially available β-glucanase. FindingsSuccessful build-up of multilayers was confirmed with QCM-D and SE. Zeta potential values proved the coating of cells. There was 2 log CFU/mL decrease after coating cells with four alternating layers of chitosan and sulfated β-glucan when compared to viability of uncoated cells. The coatings were partially degraded after exposure to simulated intestinal fluid and restructured as a result of β-glucanase treatment, mimicking enzymes present in the microflora of the human gut, but seemed to resist acidic gastric conditions. Therefore, coatings of chitosan and sulfated β-glucan can potentially be exploited as carriers for probiotics and delicate nutraceuticals.

PHYSICOCHEMICAL AND MICROBIOLOGICAL CHARACTERISTICS OF THE WASTE DUMPS AFTER COAL ENRICHMENT

Aim. The physical-chemical and microbiological characteristics of technogenic substrates depending on the duration of their storage have been studied. Methods. Atomic emission and atomic absorption spectroscopy, potentiometric method and the author’s patented electrochemical cell, standard microbiological method of cumulative cultures. Results. It was established, that during long storage of waste dumps there occurs the components concentration and oxidation of metal ions, that were found in the waste dumps, to the highest degree of oxidation and were formed more stable equilibrium structures. The effect of indigenous microbiota of waste dumps to increase their resistance to the processing has been shown. As it has been shown the indigenous microbiota of waste dumps are facilitated of increase their resistance to the recycling. The cumulative culture of microorganisms of different physiological groups forming microbiocenosis of waste dumps were obtained and quantified. The quantitative predominance of representatives of major groups of chemolithotrophic acidophilus bacteria (both mesophilic and moderately thermophilic) of indigenous microbiota from waste dumps with extended storage period, has been established. That, in turn, leads to a more pronounced effect of microbiota on the physicochemical characteristics of these waste dumps. Conclusion. The physical, chemical and microbiological changes are significant in storage dumps composition in the process of their accumulation. This should be taken into account in selecting the conditions of utilization of technogenic substrates by biotechnological methods using active members of their own microbiota.

Probiotic biological strategies to decontaminate aflatoxin M1 in a traditional Iranian fermented milk drink (Doogh)

Aflatoxin M1 is an important mycotoxin mostly found in milk and dairy products. The main objective of this work was to study the effects of probiotic strains, a probiotic inoculated population, the physiology of probiotic bacteria and final fermentation pH at four consecutive stages on the reduction of 0.500 ppb of free aflatoxin M1 (AFM1) in Doogh (a traditional Iranian fermented milk drink). Samples’ biochemical, microbial and AFM1 binding characteristics were monitored during fermentation and storage (5 °C for 28 days). An immunoaffinity column was used to extract AFM1 and a high-performance liquid chromatograph with a fluorescence detector was used to measure it. Results showed that Lactobacillus acidophilus was probiotic strain that most reduced free AFM1. Inoculation of L. acidophilus at 9 log cfu/mL, despite the higher cost, revealed significantly higher free AFM1 binding capacity than 7 log cfu/mL. Heat-killed (dead) L. acidophilus bacteria reduced less free AFM1 at the end of storage than viable. Samples with a final fermentation pH of 4.5 bound more free AFM1 during fermentation and storage than those with a pH of 4.2. It is concluded that inoculation of 7 log cfu/mL L. acidophilus viable cells in Doogh with a final fermentation pH of 4.5 supplied a safety- and health-promoting and cost-effective drink.

Probiotic feeding affects T cell populations in blood and lymphoid organs in chickens.

This study was performed to evaluate the effects of Lactobacillus acidophilus bacteria as a probiotic on chicken T cell subset populations in peripheral blood and lymphoid tissues. Thirty chickens were divided into three groups and fed sterilised cow milk, a mixture of milk and L. acidophilus (probiotic), or neither, as the control group. Chickens were euthanised after 14 and 21 days, and whole blood and ileal, bursal, and caecal tonsillar tissues were collected. The populations of T cell subsets, including CD4+, CD8+, and TCR1+ cells, were evaluated by immunohistochemistry and flow cytometry. After 21 days of treatment the percentage of blood CD4+, CD8+, and TCR1+ cells was significantly higher in the probiotic-fed group than in the control group. After 14 days of treatment, a significantly greater number of CD4+ T cells were found in the ileum of probiotic-fed chickens than in chickens from the other two groups. This difference was even greater after 21 days. In addition, after 21 days, a significantly greater number of TCR1+ cells were found in the caecal tonsils of milk-fed chickens than in chickens from the control group. The findings indicate that probiotics may alter the distribution of T cells in the blood and lymphoid tissues in young chickens; however, transient changes in lymphoid tissues indicate that probiotics likely do not permanently affect mucosal immunity.

Comparison of Three Treatments (Two Fermented Treatments and One Nonfermented Treatment) in Production of Synbiotic Ice Cream

Synbiotic ice cream was produced by adding probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium lactis) and inulin as prebiotic compound. Three samples of synbiotic ice cream were produced: the first and second samples were prepared by addition of probiotic culture accompanied with and without fermentation of ice cream mixture, respectively. The third was prepared by adding fermented milk to ice cream formulation. The sample produced by fermented milk had the highest over run. The lowest acidity was related to nonfermented sample. Adding fermented milk can increased probiotic bacterial number in synbiotic ice cream so that in this treatment, probiotic bacterial count after one day of preparation was equaled to 6/94 log cfu/mL which reached to 6/851 log cfu/mL after 16 weeks of storage. Moreover, adding fermented milk improved sensory properties of synbiotic ice cream. Practical Application Nowadays, synbiotic dairy products such as symbiotic ice cream are considered by consumers. Ice cream could be used as a carrier for intake of probiotics and prebiotics if freezing and thawing do not cause damage to the probiotic bacterial cells and the final product properties are preserved. In this study, three treatments (two fermented treatments and one nonfermented treatment) were compared for production of synbiotic ice cream. We found that adding fermented milk to ice cream formulation increased viability of probiotic bacteria and improved organoleptic quality of synbiotic ice cream. Therefore, it is possible to produce functional ice cream in favor of customers especially children.

The Effect of Lactobacillus acidophilus and Chito−Oligosaccharide on Antibacterial Activity and Organic Acid Production

The effect of Lactobacillus acidophilus combined with and without Chito-Oligosaccharide (COS) on the growth of Escherichia coli and Staphylococcus aureus had been studied. The antibacterial activity of L. acidophilus before and after combination with COS 0.2% was tested on bacteria of E. coli and S. aureus with well-diffusion method. Incubation time was carried out in 44, 46, 48, 50, and 52 hours. Organic acids produced by L. acidophilus bacteria was measured by HPLC. The result showed that COS 0.2% can inhibit the growth of E. coli and S. aureus 37.2 mm 2 and 52 mm 2 respectively. Combination of L. acidophilus and COS 0.2% gave inhibition zone larger than L. acidophilus without COS 0.2% . Incubation time within 48 hours of L. acidophilus combined with COS 0.2% produced the largest inhibition zone against E. coli and S. aureus 367.92 mm 2 and 343.99 mm 2 respectively. Optical density measurement resulted in higher value for combination one but concentration of organic acid produced was lower compare to L. acidophilus without COS 0.2%. Keywords: COS, L. acidophilus, Organic acid, antibacterial.

Differential proteome and cellular adhesion analyses of the probiotic bacterium Lactobacillus acidophilus NCFM grown on raffinose - an emerging prebiotic.

Whole cell and surface proteomes were analyzed together with adhesive properties of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) grown on the emerging prebiotic raffinose, exemplifying a synbiotic. Adhesion of NCFM to mucin and intestinal HT-29 cells increased three-fold after culture with raffinose versus glucose, as also visualized by scanning electron microscopy. Comparative proteomics using 2D-DIGE showed 43 unique proteins to change in relative abundance in whole cell lysates from NCFM grown on raffinose compared to glucose. Furthermore, 14 unique proteins in 18 spots of the surface subproteome underwent changes identified by differential 2DE, including elongation factor G, thermostable pullulanase, and phosphate starvation inducible stress-related protein increasing in a range of +2.1 -+4.7 fold. By contrast five known moonlighting proteins decreased in relative abundance by up to-2.4 fold. Enzymes involved in raffinose catabolism were elevated in the whole cell proteome; α-galactosidase (+13.9fold); sucrose phosphorylase (+5.4 fold) together with metabolic enzymes from the Leloir pathway for galactose utilization and the glycolysis; β-galactosidase (+5.7 fold); galactose (+2.9/+3.1 fold) and fructose (+2.8 fold) kinases. The insights at the molecular and cellular levels contributed to the understanding of the interplay of a synbiotic composed of NCFM and raffinose with the host.

Optimization of affecting factors to glucuronic acid production in mature coconut fermentation

The process of mature coconut water fermentation by the complex of two bacteria strains Gluconacetobacter nataicola and Lactobacillus acidophilus in order to get high glucuronic acid concentration was studied. A Blackett – Burman matrix was designed to study the factors that affect glucuronic acid formation. After screening, four factors included G. Nataicola density, L. acidophilus density, sucrose concentration and temperature that have strongly contributed to glucuronic acid formation was selected to design a matrix for modeling optimal point. The result of Response surface methodology (RSM) with Central composite design (CCD) showed the maximum value of glucuronic acid concentration 94.23mg/l at 4.79 logCFU/ml G. Nataicola density, 5.34 logCFU/ml L. acidophilus density, 8.99 % sucrose and incubation at 31.96oC, respectively. The highest value of glucuronic acid concentration in the practical model was 94.23 mg/l.

In vitro fabrication of dental filling nanopowder by green route and its antibacterial activity against dental pathogens

The aim of this study was to introduce novel Sn, Cu, Hg, and Ag nanopowders (NPs) and a composite nanopowder (NP) synthesized using Salvia miltiorrhiza Bunge (SM) root extract as a reducing and capping agent to improve the antibacterial property of dental filling materials. All of the NPs obtained were characterized using a scanning transmission electron microscope (STEM), and energy dispersive X-ray (EDX) spectrum imaging was performed to map the elemental distributions of the NP composite. Fourier transform infrared (FTIR) spectroscopy was performed to identify the role of various functional groups in all of the obtained NPs and the phyto-compound responsible for the reduction of various metal ions. The X-ray diffraction (XRD) patterns clearly illustrated the crystalline phase of the synthesized NP. The antibacterial properties of the synthesized Sn, Cu, Hg, Ag, composite NP, SM root extract, and commercial amalgam powder were evaluated. The Cu, composite NP, SM root extract and Ag NP displayed excellent antibacterial activity against dental bacteria Streptococcus mutans and Lactobacillus acidophilus. The results of this study require further evaluation for signs of metal toxicity in appropriate animal models. However, the results are encouraging for the application of metal NPs as suitable alternatives for antibiotics and disinfectants, especially in dental filling materials.

Salt Reduction in a Model High-Salt Akawi Cheese: Effects on Bacterial Activity, pH, Moisture, Potential Bioactive Peptides, Amino Acids, and Growth of Human Colon Cells.

This study evaluated the effects of sodium chloride reduction and its substitution with potassium chloride on Akawi cheese during storage for 30 d at 4 °C. Survival of probiotic bacteria (Lactobacillus acidophilus, Lactobacillus casei, and Bifidobacterium longum) and starter bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus), angiotensin-converting enzyme-inhibitory and antioxidant activities, and concentrations of standard amino acids as affected by storage in different brine solutions (10% NaCl, 7.5% NaCl, 7.5% NaCl+KCl [1:1], 5% NaCl, and 5% NaCl+KCl [1:1]) were investigated. Furthermore, viability of human colon cells and human colon cancer cells as affected by the extract showing improved peptide profiles, highest release of amino acids and antioxidant activity (that is, from cheese brined in 7.5% NaCl+KCl) was evaluated. Significant increase was observed in survival of probiotic bacteria in cheeses with low salt after 30 d. Calcium content decreased slightly during storage in all cheeses brined in various solutions. Further, no significant changes were observed in ACE-inhibitory activity and antioxidant activity of cheeses during storage. Interestingly, concentrations of 4 essential amino acids (phenylalanine, tryptophan, valine, and leucine) increased significantly during storage in brine solutions containing 7.5% total salt. Low concentration of cheese extract (100 μg/mL) significantly improved the growth of normal human colon cells, and reduced the growth of human colon cancer cells. Overall, the study revealed that cheese extracts from reduced-NaCl brine improved the growth of human colon cells, and the release of essential amino acids, but did not affect the activities of potential bioactive peptides.

DETERMINATION OF AFLATOXIN M1 LEVEL IN MILK AND SOME DAIRY PRODUCTS

The present study was carried out in the laboratory of agricultural microbiology Department, faculty of agriculture, Zagazig University, Egypt, in summer and winter seasons 2013 and 2014. In order to study the aflatoxin M1 (AFM1) contamination in milk, kareish cheese and yoghurt. AFMI was detected in raw milk in only 10 out of 12 samples (83.3%) in each season. Winter season had higher AFMI concentration than summer season with the mean values of 311.8 and 207.0 ng/l, respectively. AFMI was detected in all samples of kareish cheese (24 samples) in summer as well as in winter season. Winter season had higher AFMI concentration than summer season with average values of 651.36 and 527.40 ng/kg, respectively. The present results observed that 83.33% of cheese sample examined exceeding the limits of EU (50 ng/kg), and (70.83%) of cheese samples examined exceeding the limits of codex (500 ng/kg) in both summer and winter seasons. In yoghurt, the AFMI did not detect in 3 out of 12 samples of yoghurt tested. In summer season the positive samples ranged from 31.46 to 66.05 ng/kg with average of 39.13 ng/kg. AFMI did not detect in only one out of 12 samples tested in winter season. Also, the positive samples ranged from 56.6 to 84.14 ng/kg with an average of 64.68 ng/kg. Cheese had a higher concentration of AFMI than both raw milk and yoghurt. Also, yoghurt had the lowest concentration of AFMI comparing to raw milk and cheese. Heating treatments reduced the concentrations of AFMI in all raw milk samples tested. Boiling caused 26.71% degradion of AFMI, whereas pasteurization caused only 15.45% degredation. In yoghurt, two strains of probiotic bacteria (lactobacillus acidophilus and Bifidobacterium lactis) individually were gradually reduced the concentration of AFMI in contaminated milk with 25 ppt, as a function of time with complete elimination by the end of storage period (3 days) at refrigerator, while the cocktail of the two strains showed more ability for reducing AFMI. Both probiotic bacteria (L. acidophilus and B. lactis) showed more ability for reducing AFMI in contaminated milk with 50.0 ppt or 75 ppt.The most important reductions of AFMI concentration were 41.80 ppt (45.3%), 2.6 ppt (69.90%) and 7.12 ppt (92.8%) which achieved by using the same concentration individually of each strain and in combination, respectively, in contaminated milk with 75ppt after two days. No AFMI was detected using combined strains after three days.

Antioxidant Effect ofLactobacillus acidophilusas a Probiotic at Different Time Intervals

Background: Probiotics are survival microorganisms that, when administered in sufficient amounts, confer health benefits to the host and can be used in an antioxidative role. Objectives: The antioxidative effect of whole cells and intracellular cell-free extracts of the lactic acid bacteria Lactobacillus acidophilus (PTCC 1643) as a probiotic at three different time intervals was investigated. Materials and Methods: Antioxidant biomarkers, such as total antioxidant power (TAP), measured with the FRAP (ferric-reducing ability of plasma) method, were evaluated at 24, 48, and 72 hours. Results: The results showed that extracts and bacteria of L. acidophilus were able to significantly increase TAP after 24 and 72 hours. Conclusions: The results showed that the effect of L. acidophilus is time-dependent.

Effects of whey peptide extract on the growth of probiotics and gut microbiota

Whey peptide extract with molecular weight below 1 kDa was investigated in microplate assay, and viable cells, as well as metabolic activity were determined to evaluate augmented growth of probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium animalis). Results illustrated that whey peptide extract 1% (w/v) has the capacity to stimulate the proliferation of both probiotic bacteria tested, further supported by the faster generation of metabolic products. The effect of whey peptide extract on the modulation of gut microbiota was also examined in Wistar rats fed either with a standard or a high-fat diet, assessed via 16S ribosomal RNA expression of gut microbiota by quantitative PCR. Relative abundance of Lactobacillus spp., Bifidobacterium spp. and Bacteroidetes was significantly increased by whey peptide extract in rats fed with a standard diet. These results highlight an additional unexploited positive effect of whey peptide extract on gut microbiota modulation.

Microbial cells as colloidal particles: Pickering oil-in-water emulsions stabilized by bacteria and yeast

ABSTRACT Thermally-inactivated baker's yeast (Saccharomyces cerevisiae) and lactic acid bacteria (Lactobacillus acidophilus and Streptococcus thermophilus) were used to generate and stabilize model oil-in-water (O/W) emulsions containing up to 80 wt.% dispersed oil. With optimized compositions, cell-covered dispersed oil droplets were stable against droplet coalescence and bulk phase separation for over four months. From a textural perspective, these emulsions were self-supporting and exhibited a mayonnaise-like consistency. The microbial cells acted as Pickering-type stabilizers by residing at the oil–water interface. The three-phase contact angle of the yeast at the oil–water interface measured using confocal microscopy was 30 ± 9°, demonstrating its ability to stabilize O/W emulsions. These microbial cells may be used in the design of processed food emulsions with an ‘all-natural’ designation as well as for the replacement of common synthetic surfactants to permit clean label declarations.

The Effect of Fe3O4 Nanoparticles on Survival of Probiotic Bacteria Lactobacillus acidophilus PCM2499 at Lower pH

This paper presents a description of an experiment in which the survival rate of the probiotic bacteria Lactobacillus acidophilus PCM2499 was increased only due to the presence of Fe3O4 magnetic nanoparticles. The survival rate increased from 1.3 to 10 times compare to the control. It has been shown that the minimum concentration of NPs with a positive effect equals 8 mg/ml and the maximum concentration of the NPs equals 24 mg/ml.

Biosynthesis and Structural Characteristics of Selenium Nanoparticles using Lactobacillus Acidophilus Bacteria by Wet Sterilization Process

A facile ecofriendly biological approach for the synthesis of selenium nanoparticles using the probiotic Lactobacillus acidophilus bacteria and its characterization is reported in this paper. The synthesized selenium nanoparticles were characterized using UV spectrometer, X-ray diffraction and transmission electron microscopy. The results of X-ray diffraction and transmission electron microscopic studies showed that the nanoparticles were in the uniform size range of 15-50 nm. The present study showed that no chemical changes occurred in selenium nanoparticles during the wet sterilization process and therefore, the wet sterilization method can effectively use to recover the elemental selenium from bacterial cells.

Reducing acrylamide in fried potato pancake using baker’s yeast, lactobacilli and microalgae

In preparation of fried potato pancake, dough was fermented with six strains of lactic acid bacteria (Lactobacillus plantarum, Lactobacillus delbrueckii, Lactobacillus helveticus, Lactobacillus acidophilus, Lactobacillus reuteri and Lactobacillus casei; 108 cfu/g dough), baker’s yeast (2.6x107−7.8x107 cfu/g dough), and also treated with inactivated microalgae powder (Dunaliella salina; 0.01 g/g dough) as an additive, in combination or not. After treatment, texture and colour attributes of fried potato pancakes were determined. After fermentation for 2 h, baker’s yeast reduced 85% of acrylamide (AA). L. acidophilus was the most efficient bacterial strain under study and reduced 60% AA, and similar results were obtained with microalgae. Compared to the control, AA was eliminated when microalgae were combined with either yeast or lactic acid bacteria, and the resulting fried potato pancake was lighter in colour and had a softer texture when fermented with lactic acid bacteria or yeast.

Screening, Isolation and Identification of Probiotic Producing Lactobacillus acidophilus Strains EMBS081 & EMBS082 by 16S rRNA Gene Sequencing.

16S rDNA sequencing which has gained wide popularity amongst microbiologists for the molecular characterization and identification of newly discovered isolates provides accurate identification of isolates down to the level of sub-species (strain). Its most important advantage over the traditional biochemical characterization methods is that it can provide an accurate identification of strains with atypical phenotypic characters as well. The following work is an application of 16S rRNA gene sequencing approach to identify a novel species of Probiotic Lactobacillus acidophilus. The sample was collected from pond water samples of rural and urban areas of Krishna district, Vijayawada, Andhra Pradesh, India. Subsequently, the sample was serially diluted and the aliquots were incubated for a suitable time period following which the suspected colony was subjected to 16S rDNA sequencing. The sequence aligned against other species was concluded to be a novel, Probiotic L. acidophilus bacteria, further which were named L. acidophilus strain EMBS081 & EMBS082. After the sequence characterization, the isolate was deposited in GenBank Database, maintained by the National Centre for Biotechnology Information NCBI. The sequence can also be retrieve from EMBL and DDBJ repositories with accession numbers JX255677 and KC150145.