scholarly journals The Ability of Lactobacillus rhamnosus in Solution, Spray-Dried or Lyophilized to Bind Aflatoxin B1

2014 ◽  
Vol 3 (2) ◽  
pp. 35 ◽  
Author(s):  
Fernanda Bovo ◽  
Larissa Tuanny Franco ◽  
Roice Eliana Rosim ◽  
Carmen Silvia Favaro Trindade ◽  
Carlos Augusto Fernandes de Oliveira
Keyword(s):  
Cell Wall ◽  
High Performance ◽  
Binding Capacity ◽  
Lactobacillus Rhamnosus ◽  
Aflatoxin Contamination ◽  
Freeze Dried ◽  
Structural And Functional Properties ◽  
Aflatoxin B ◽  
Spray Dried

<p>Aflatoxin B<sub>1</sub> (AFB<sub>1</sub>) can cause carcinogenic, mutagenic, teratogenic and immunosuppressive effects in humans and animals. Several lactic acid bacteria species have the ability to bind AFB<sub>1 </sub><em>in vitro</em>, showing a potential application for reducing the bioavailability of AFB<sub>1</sub> in contaminated products. Thus, the aim of this study was to evaluate the capacity of <em>Lactobacillus rhamnosus</em>, non-viable and dried, in removing the AFB<sub>1</sub> from a contaminated medium. <em>L. rhamnosus</em> were cultured in MRS broth, sterilized (121 ºC, 15 min.) to inactivate their metabolism and then dried by spray-drying or freeze-drying (lyophilization). Binding assays using AFB<sub>1</sub> (1.0 µg/ml) and <em>L. rhamnosus</em> cells (1×10<sup>10</sup> cells, in suspension or spray-dried or freeze-dried) were conducted at pH 3.0 and 6.0, room temperature and contact time of 60 min. Quantification of AFB<sub>1</sub> was achieved by high performance liquid chromatography. Scanning electron microscope was also performed in order to analyze the drying effect on the atomized and lyophilized <em>L. rhamnosus</em> cells. For pH 3.0 and 6.0, there were no significant differences between AFB<sub>1</sub> binding efficiency by <em>L. rhamnosus</em> cells in solution (45.9 ± 8.8% and 35.8 ± 7.7%, respectively) or freeze-dried (36.6 ± 7.1% and 27.2 ± 4.0%, respectively). However, the spray-dried cells lost completely the AFB<sub>1</sub> binding capacity during atomization, which damaged the structural and functional properties of the bacterial cell wall. In conclusion, <em>L. rhamnosus</em> retained its AFB<sub>1</sub> binding ability only when its cell wall remained intact as observed in the lyophilization procedure. Lyophilized <em>L. rhamnosus</em> cells therefore can be a practicable alternative for decontamination of food products susceptible to aflatoxin contamination.</p>

In Vitro Aflatoxin B1 Binding by the Cell Wall and (1→3)-β-d-Glucan of Baker's Yeast

2018 ◽  
Vol 81 (4) ◽  
pp. 670-676 ◽  
Author(s):  
MOHAMMAD HADI AAZAMI ◽  
MOHAMMAD HASAN FATHI NASRI ◽  
MOHSEN MOJTAHEDI ◽  
SHAHLA ROUDBAR MOHAMMADI
Keyword(s):  
Cell Wall ◽  
Aflatoxin B1 ◽  
Contact Time ◽  
High Performance ◽  
Binding Capacity ◽  
Baker’S Yeast ◽  
Baker's Yeast ◽  
Yeast Saccharomyces Cerevisiae ◽  
Modified Method

ABSTRACT The aim of this study was to evaluate the ability of heat-killed baker's yeast (HKBY), the cell wall of baker's yeast (CWBY), and cell wall (1→3)-β-d-glucan of baker's yeast (BGBY) to bind aflatoxin B1 (AFB1) in phosphate-buffered saline (PBS) spiked with 0.5 μg/mL AFB1. Baker's yeast (Saccharomyces cerevisiae) was heat killed by autoclaving at 121°C for 10 min. The cell wall was physically extracted, and (1→3)-β-d-glucan was extracted by a modified method. The concentration of AFB1 was determined by high-performance liquid chromatography after exposure to binders for three contact times, 30 min, 5 h, and 24 h, at room temperature. AFB1 binding by HKBY, CWBY, and BGBY was 6.30 to 46.34%. The lowest binding capacity was found for HKBY with a contact time of 30 min, and the highest binding capacity was found for BGBY with a contact time of 24 h. Among binders, CWBY had the highest binder-AFB1 complex stability during washing with PBS, and the lowest stability was found for HKBY complexes. Results of this study indicated that BGBY was the most effective binder, and more exposure to BGBY removes more AFB1 from PBS.

In vitro effect of Lactobacillus rhamnosus GG on reduction of aflatoxin B1

2014 ◽  
Vol 44 (1) ◽  
pp. 32-40 ◽  
Author(s):  
Parya Rahnama Vosough ◽  
Ali Mohamadi Sani ◽  
Masoumeh Mehraban ◽  
Reza Karazhyan
Keyword(s):  
Binding Capacity ◽  
Lactobacillus Rhamnosus ◽  
Content Type ◽  
Significant Difference ◽  
Toxin Removal ◽  
Viable Bacteria ◽  
Elisa Technique ◽  
Aflatoxin B ◽  
Vitro Effect

Purpose – Since a sound detoxification method is needed for controlling aflatoxin B1 (AFB1), as one of the most harmful mycotoxins in animal production and food industry, this study was performed. The paper aims to discuss these issues. Design/methodology/approach – This study was conducted to examine the ability of Lactobacillus rhamnosus strain GG to remove AFB1 from liquid media. The binding of AFB1 to Lb. rhamnosus GG was studied for viable, heat-killed and acid-killed bacteria. AFB1 at concentrations (5, 10 and 20 μg/l) was added to the bacterial culture (109 cfu/ml) in MRS broth medium and incubated at 25°C for 4, 12 and 24 h. The aflatoxin-binding capacity of the strain was quantified by the amount of unbound AFB1 using ELISA technique. Findings – Results showed the AFB1-binding capacity of viable, heat-killed and acid-killed bacteria was about 43, 49 and 50 percent, respectively. The percentage of AFB1 removed was the highest amount in low (5 μg/l) and high (20 μg/l) concentrations, and there was no significant difference between them (p=0.05). These findings suggest that lactic acid bacteria can be exploited as an approach to detoxification of aflatoxins from foods. Practical implications – This method is safe because non-viable bacteria have more ability to remove toxin than viable bacteria, and also it is an effective method with 50 percent approximately toxin removal. Originality/value – Since there has been no research on the ability of this strain on the removal of AFB1, the authors assessed the ability of the strain in high levels of AFB1.

scholarly journals Lactobacillus rhamnosus Strain GG Reduces Aflatoxin B1 Transport, Metabolism, and Toxicity in Caco-2 Cells

2007 ◽  
Vol 73 (12) ◽  
pp. 3958-3964 ◽  
Author(s):  
S. Gratz ◽  
Q. K. Wu ◽  
H. El-Nezami ◽  
R. O. Juvonen ◽  
H. Mykk�nen ◽  
...  
Keyword(s):  
High Performance ◽  
Culture Medium ◽  
Lactobacillus Rhamnosus ◽  
Dietary Exposure ◽  
Transepithelial Resistance ◽  
Aflatoxin B ◽  
Cytochrome P 450 ◽  
In Cells

ABSTRACT The probiotic Lactobacillus rhamnosus GG is able to bind the potent hepatocarcinogen aflatoxin B1 (AFB1) and thus potentially restrict its rapid absorption from the intestine. In this study we investigated the potential of GG to reduce AFB1 availability in vitro in Caco-2 cells adapted to express cytochrome P-450 (CYP) 3A4, such that both transport and toxicity could be assessed. Caco-2 cells were grown as confluent monolayers on transmembrane filters for 21 days prior to all studies. AFB1 levels in culture medium were measured by high-performance liquid chromatography. In CYP 3A4-induced monolayers, AFB1 transport from the apical to the basolateral chamber was reduced from 11.1% � 1.9% to 6.4% � 2.5% (P = 0.019) and to 3.3% � 1.8% (P = 0.002) within the first hour in monolayers coincubated with GG (1 � 1010 and 5 � 1010 CFU/ml, respectively). GG (1 � 1010 and 5 � 1010 CFU/ml) bound 40.1% � 8.3% and 61.0% � 6.0% of added AFB1 after 1 h, respectively. AFB1 caused significant reductions of 30.1% (P = 0.01), 49.4% (P = 0.004), and 64.4% (P < 0.001) in transepithelial resistance after 24, 48, and 72 h, respectively. Coincubation with 1 � 1010 CFU/ml GG after 24 h protected against AFB1-induced reductions in transepithelial resistance at both 24 h (P = 0.002) and 48 h (P = 0.04). DNA fragmentation was apparent in cells treated only with AFB1 cells but not in cells coincubated with either 1 � 1010 or 5 � 1010 CFU/ml GG. GG reduced AFB1 uptake and protected against both membrane and DNA damage in the Caco-2 model. These data are suggestive of a beneficial role of GG against dietary exposure to aflatoxin.

scholarly journals In Vitro Activity of Balanites aegyptiaca and Tamarindus indica Fruit Extracts on Growth and Aflatoxigenicity of Aspergillus flavus and A. parasiticus

2013 ◽  
Vol 2 (4) ◽  
pp. 68 ◽  
Author(s):  
Saifeldin Ahmed El-nagerabi ◽  
Abdulkadir E. Elshafie ◽  
Mohamed R. Elamin
Keyword(s):  
Aspergillus Flavus ◽  
Fungal Growth ◽  
Aflatoxin Contamination ◽  
Tamarindus Indica ◽  
Balanites Aegyptiaca ◽  
Total Aflatoxin ◽  
Animal Products ◽  
Fruit Extracts ◽  
Aflatoxin B

<p>Aflatoxin and especially aflatoxin B<sub>1</sub> (AFB<sub>1</sub>) is a carcinogenic secondary metabolite synthesized by certain <em>Aspergillus </em>species. They contaminate natural and processed agricultural and animal products which render them unfit for consumption. The aim of this study was to evaluate the <em>in vitro</em> effects of <em>Balanites aegyptiaca</em> and <em>Tamarindus indica</em> fruit extracts on the growth and aflatoxin secretion of <em>Aspergillus flavus</em> (SQU21) and <em>A. parasiticus </em>(CBS921.7) strains. The two fruit extracts significantly (<em>P </em>&lt; 0.05) reduced aflatoxin and did not inhibit mycelial dry weights of the two <em>Aspergillus </em>strains. At different concentrations of balanites (2.5-10%), the inhibition of total aflatoxin was 49.9-84.8% for <em>A. flavus</em> (SQU21) and 32.1-84.4% for <em>A. parasiticus</em> (CBS921.7), whereas the inhibition of aflatoxin Bwas 38.2-81.4% and 32.8-80.6% for the two strains. Tamarind fruit extract (2.5-7.5%) caused 28.8-84.2% and 40.7-85.5% reductions in total aflatoxin and 37.1-83.5% and 33.9-85.9% in aflatoxin B for the two strains, respectively. None of these extracts inhibited the fungal growth or detoxified synthetic aflatoxin B<sub>1</sub>. We have concluded that these fruits contain various inhibitors to aflatoxin biosynthesis and secretion. Therefore, they can be used in combination as safe green biopreservatives to combat aflatoxin contamination of food.</p>

scholarly journals In vitro binding of mutagenic heterocyclic aromatic amines by Bifidobacterium pseudocatenulatum G4

2010 ◽  
Vol 1 (2) ◽  
pp. 149-154 ◽  
Author(s):  
F. Faridnia ◽  
A. Hussin ◽  
N. Saari ◽  
S. Mustafa ◽  
L. Yee ◽  
...  
Keyword(s):  
High Performance ◽  
Binding Capacity ◽  
Bifidobacterium Longum ◽  
Heterocyclic Amines ◽  
Heterocyclic Aromatic Amines ◽  
Human Origin ◽  
Bacterial Strains ◽  
In Vitro Binding ◽  
Vitro Binding

Consumption of probiotics has been associated with decreased risk of colon cancer and reported to have antimutagenic/ anti-carcinogenic properties. One possible mechanism for this effect involves physical binding of the mutagenic compounds, such as heterocyclic amines (HCAs), to the bacteria. Therefore, the objective of this study was to examine the binding capacity of bifidobacterial strains of human origin on mutagenic heterocyclic amines which are suspected to play a role in human cancers. In vitro binding of the mutagens Trp-p-2, IQ, MeIQx, 7,8DiMeIQx and PhIP by three bacterial strains in two media of different pH was analysed using high performance liquid chromatography. Bifidobacterium pseudocatenulatum G4 showed the highest decrease in the total HCAs content, followed by Bifidobacterium longum, and Escherichia coli. pH affects binding capacity; the highest binding was obtained at pH 6.8. Gram-positive tested strains were found to be consistently more effective than the gram-negative strain. There were significant decreases in the amount of HCAs in the presence of different cell concentrations of B. pseudocatenulatum G4; the highest decrease was detected at the concentration of 1010 cfu/ml. The results showed that HCAs were able to bind with all bacterial strains tested in vitro, thus it may be possible to decrease their absorption by human intestine and increase their elimination via faeces.

scholarly journals Human Antibodies against a Purified Glucosylceramide from Cryptococcus neoformans Inhibit Cell Budding and Fungal Growth

2000 ◽  
Vol 68 (12) ◽  
pp. 7049-7060 ◽  
Author(s):  
Marcio L. Rodrigues ◽  
Luiz R. Travassos ◽  
Kildare R. Miranda ◽  
Anderson J. Franzen ◽  
Sonia Rozental ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cell Wall ◽  
Cryptococcus Neoformans ◽  
High Performance ◽  
Fungal Growth ◽  
Fungal Cell ◽  
Human Antibodies ◽  
Different Strains ◽  
Immunofluorescence Labeling

ABSTRACT A major ceramide monohexoside (CMH) was purified from lipidic extracts of Cryptococcus neoformans. This molecule was analyzed by high-performance thin-layer chromatography (HPTLC), gas chromatography coupled with mass spectrometry, and fast atom bombardment-mass spectrometry. The cryptococcal CMH is a β-glucosylceramide, with the carbohydrate residue attached to 9-methyl-4,8-sphingadienine in amidic linkage to 2-hydroxyoctadecanoic acid. Sera from patients with cryptococcosis and a few other mycoses reacted with the cryptococcal CMH. Specific antibodies were purified from patients' sera by immunoadsorption on the purified glycolipid followed by protein G affinity chromatography. The purified antibodies to CMH (mainly immunoglobulin G1) bound to different strains and serological types of C. neoformans, as shown by flow cytofluorimetry and immunofluorescence labeling. Transmission electron microscopy of yeasts labeled with immunogold-antibodies to CMH and immunostaining of isolated cell wall lipid extracts separated by HPTLC showed that the cryptococcal CMH predominantly localizes to the fungal cell wall. Confocal microscopy revealed that the β-glucosylceramide accumulates mostly at the budding sites of dividing cells with a more disperse distribution at the cell surface of nondividing cells. The increased density of sphingolipid molecules seems to correlate with thickening of the cell wall, hence with its biosynthesis. The addition of human antibodies to CMH to cryptococcal cultures of both acapsular and encapsulated strains of C. neoformans inhibited cell budding and cell growth. This process was complement-independent and reversible upon removal of the antibodies. The present data suggest that the cryptococcal β-glucosylceramide is a fungal antigen that plays a role on the cell wall synthesis and yeast budding and that antibodies raised against this component are inhibitory in vitro.

scholarly journals Aflatoxin contamination in Tanzania: quantifying the problem in maize and groundnuts from rural households

2021 ◽  
pp. 1-12
Author(s):  
S.B. Boni ◽  
F. Beed ◽  
M.E. Kimanya ◽  
E. Koyano ◽  
O. Mponda ◽  
...  
Keyword(s):  
Body Weight ◽  
High Performance ◽  
Animal Health ◽  
Daily Intake ◽  
Aflatoxin Contamination ◽  
Aflatoxin Level ◽  
Awareness Campaigns ◽  
Food And Feed ◽  
The Mean ◽  
Aflatoxin B

Aflatoxins are toxic and carcinogenic secondary metabolites, produced by Aspergillus flavus and Aspergillus parasiticus, which contaminate food and feed and threaten human and animal health. To assess the prevalence of aflatoxins in Tanzania, 180 groundnut and 200 maize samples were collected from 9 and 10 districts, respectively. Aflatoxin contamination was quantified using high performance liquid chromatography. Aflatoxins were detected in samples collected from all districts and prevalence ranged from 92 to 100% for groundnuts and 10 to 80% for maize. The mean aflatoxin level for groundnuts was 6.37 μg/kg and the highly contaminated sample had 40.31 μg/kg. For maize, the mean aflatoxin level was 12.47 μg/kg and the highly contaminated sample had 162.40 μg/kg. The estimated average probable daily intake (APDI) of aflatoxin B1 (AFB1) from groundnuts consumption was 1.88 ng/kg body weight/day, while for maize, it ranged between 151.98-272.89 ng/kg body weight/day. The APDI for both groundnut and maize exceeded the provisional maximum tolerable daily intake (PMTDI) of AFB1 for adults (1 ng/kg body weight/day), bringing about health concerns for populations in Tanzania. Another alarming finding was that 75% of the farmers who provided samples for analysis were not aware of aflatoxins or the negative health impacts from consuming contaminated products. Results reported in this paper show that aflatoxin contaminated staple crops are widely distributed in Tanzania and that the risk of human exposure is high due to diet preferences. Awareness campaigns are required to inform and protect farmers and consumers.

scholarly journals Lactobacillus rhamnosus GG Genomic and Phenotypic Stability in an Industrial Production Process

2020 ◽  
Vol 86 (6) ◽  
Author(s):  
Marianne Stage ◽  
Anita Wichmann ◽  
Mette Jørgensen ◽  
Natalia Ivonne Vera-Jimenéz ◽  
Malue Wielje ◽  
...  
Keyword(s):  
Production Process ◽  
Gene Cluster ◽  
Industrial Production ◽  
Lactobacillus Rhamnosus ◽  
Probiotic Properties ◽  
Phenotypic Stability ◽  
Content Type ◽  
Freeze Dried ◽  
Probiotic Strains

ABSTRACT Lactobacillus rhamnosus GG is one of the most widely marketed and studied probiotic strains. In L. rhamnosus GG, the spaCBA-srtC1 gene cluster encodes pili, which are important for some of the probiotic properties of the strain. A previous study showed that the DNA sequence of the spaCBA-srtC1 gene cluster was not present in some L. rhamnosus GG variants isolated from liquid dairy products. To examine the stability of the L. rhamnosus GG genome in an industrial production process, we sequenced the genome of samples of L. rhamnosus GG (DSM 33156) collected at specific steps of the industrial production process, including the culture collection stock, intermediate fermentations, and final freeze-dried products. We found that the L. rhamnosus GG genome sequence was unchanged throughout the production process. Consequently, the spaCBA-srtC1 gene locus was intact and fully conserved in all 31 samples examined. In addition, different production batches of L. rhamnosus GG exhibited consistent phenotypes, including the presence of pili in final freeze-dried products, and consistent characteristics in in vitro assays of probiotic properties. Our data show that L. rhamnosus GG is highly stable in this industrial production process. IMPORTANCE Lactobacillus rhamnosus GG is one of the best-studied probiotic strains. One of the well-characterized features of the strain is the pili encoded by the spaCBA-srtC1 gene cluster. These pili are involved in persistence in the gastrointestinal tract and are important for the probiotic properties of L. rhamnosus GG. Previous studies demonstrated that the L. rhamnosus GG genome can be unstable under certain conditions and can lose the spaCBA-srtC1 gene cluster. Since in vitro studies have shown that the loss of the spaCBA-srtC1 gene cluster decreases certain L. rhamnosus GG probiotic properties, we assessed both the genomic stability and phenotypic properties of L. rhamnosus GG throughout an industrial production process. We found that neither genomic nor phenotypic changes occurred in the samples. Therefore, we demonstrate that L. rhamnosus GG retains the spaCBA-srtC1 cluster and exhibits excellent genomic and phenotypic stability in the specific industrial process examined here.

scholarly journals Surveillance of Aflatoxin and Microbiota Related to Brewer's Grain Destined for Swine Feed in Argentina

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Gisela A. Gerbaldo ◽  
Carina M. Pereyra ◽  
Lilia R. Cavaglieri ◽  
Francisco Ruiz ◽  
Liliana Pascual ◽  
...  
Keyword(s):  
Storage Conditions ◽  
Fungal Species ◽  
Aflatoxin Contamination ◽  
Swine Production ◽  
Natural Contamination ◽  
Contamination Levels ◽  
Aflatoxin B ◽  
Prevalent Species ◽  
Regular Practice

Córdoba province in the center of Argentina is an important area of swine production. The use of industry by-product (brewer's grain) as feedstuff for swine is a regular practice and increases animal performance on these animals production. The occurrence of aflatoxin contamination is global, causing severe problems especially in developing countries. No reports on aflatoxin B1production, micoflora, and potential aflatoxin B1producing microorganism from brewer's grain are available. The aims of this study were (1) to isolate the microbiota species from brewer's grain, (2) to determine aflatoxin B1natural contamination levels, and (3) to determine the ability ofAspergillussectionFlaviisolates to produce aflatoxinsin vitro. Physical properties, total fungal counts, lactic acid bacteria, and fungal genera distribution were determined on this substrate. In 65% of the samples, fungal counts were higher than recommended by GMP, and lactic bacterium counts ranged from1.9×105to4.4×109 CFUg−1.Aspergillusspp. prevailed over other fungal genera.Aspergillus flavuswas the prevalent species followed byA. fumigatus. Aflatoxin B1levels in the samples were higher than the recommended limits (20 ng g−1) for complementary feedstuffs. SeveralAspergillussectionFlavistrains were able to produce aflatoxin B1  in vitro. Inadequate storage conditions promote the proliferation of mycotoxin-producing fungal species. Regular monitoring of feeds is required in order to prevent chronic and acute toxic syndromes related to this kind of contamination.

scholarly journals Probiotic Enrichment and Reduction of Aflatoxins in a Traditional African Maize-Based Fermented Food

Nutrients ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 265 ◽  
Author(s):  
Alex Wacoo ◽  
Ivan Mukisa ◽  
Rehema Meeme ◽  
Stellah Byakika ◽  
Deborah Wendiro ◽  
...  
Keyword(s):  
Ph Value ◽  
Raw Materials ◽  
Starter Culture ◽  
Lactobacillus Rhamnosus ◽  
Titratable Acidity ◽  
Fermented Food ◽  
Aflatoxin Contamination ◽  
Water Soluble ◽  
Sub Saharan Africa

Fermentation of food products can be used for the delivery of probiotic bacteria and means of food detoxification, provided that probiotics are able to grow, and toxins are reduced in raw materials with minimal effects on consumer acceptability. This study evaluated probiotic enrichment and detoxification of kwete, a commonly consumed traditional fermented cereal beverage in Uganda, by the use of starter culture with the probiotic Lactobacillus rhamnosus yoba 2012 and Streptococcus thermophilus C106. Probiotic kwete was produced by fermenting a suspension of ground maize grain at 30 °C for a period of 24 h, leading to a decrease of the pH value to ≤ 4.0 and increase in titratable acidity of at least 0.2% (w/v). Probiotic kwete was acceptable to the consumers with a score of ≥6 on a 9-point hedonic scale. The products were stable over a month’s study period with a mean pH of 3.9, titratable acidity of 0.6% (w/v), and Lactobacillus rhamnosus counts >108 cfu g−1. HPLC analysis of aflatoxins of the water-soluble fraction of kwete indicated that fermentation led to an over 1000-fold reduction of aflatoxins B1, B2, G1, and G2 spiked in the raw ingredients. In vitro fluorescence spectroscopy confirmed binding of aflatoxin B1 to Lactobacillus rhamnosus with an efficiency of 83.5%. This study shows that fermentation is a means to enrich with probiotics and reduce widely occurring aflatoxin contamination of maize products that are consumed as staple foods in sub-Saharan Africa.

Sign in / Sign up

Export Citation Format

Share Document