In vitro Study of the Potential Protective Role of L actobacillus Strains by Acrylamide Binding

Detoxification of Acrylamide by Potentially Probiotic Strains of Lactic Acid Bacteria and Yeast

Some potentially probiotic strains of lactic acid bacteria (LAB) and yeast that inhabit the digestive tract of humans are known to detoxify xenobiotics, including acrylamide (AA). The objective of the subsequent research was to evaluate the AA-detoxification capability of LAB and yeast isolated from various sources. Namely, the effect of AA was tested on the growth of LAB and yeast strains, as well in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Subsequently, the AA-binding ability of LAB and yeast was investigated in various environments, including the pH, incubation temperature, cell density, and with inanimate cells. The ability of selected LAB and yeast to reduce the genotoxicity of AA was tested on Caco-2 and Hep-G2 cell lines. The results showed that all tested strains exhibited strong resistance to AA at concentrations of 5, 10, and 50 µg/mL. Also, AA was detected in the intracellular and membrane extracts of tested strains. The most effective binding strain was Pediococcus acidilactici 16 at pH = 5, cell density = 109 CFU/mL, and incubation temperature = 37 °C (87.6% of AA removed). Additionally, all tested strains reduced the genotoxicity of AA, with the greatest reduction observed at the highest concentration of 50 µg/mL. The phenomena of detoxification by potentially probiotic strains could reduce the toxic and harmful effects of AA exposure to humans every day.

Tailor-made fermentation of sourdough reduces the acrylamide content in rye crispbread and improves its sensory and nutritional characteristics

Thirty strains of lactic acid bacteria (LAB) and Saccharomyces cerevisiae E8.9 (wild type) were used to formulate fifteen combinations of starters by mixing two or three LAB with the yeast (ratio LAB: yeast, 10: 1). Such combinations were used to prepare rye sourdough and their performance in term of acidification and biochemical characteristics during fermentation at two temperatures (30 and 37 °C) and duration (4 and 8 h) were screened. The best thirteen sourdough formulations were selected and used for rye crispbread making. The analysis of acrylamide concentration demonstrated that 11 out 13 formulations resulted in significant decreases of concentration compared to the baker's yeast (control), with reductions up to 79.6 %. The rye sourdough crispbreads showed also higher amount of volatile organic compounds (VOCs) compared to the baker's yeast control. Two rye sourdough crispbreads, selected to represent the opposite extremes within the thirteen formulations in term of VOC profiles and fermentation performances, demonstrated better sensory and nutritional features, such as phytic acid reduction (up to 47.3 %), and enhanced total free amino acid compared to the control. These evidences suggest the potential of tailored sourdough fermentations as alternative and suitable biotechnological strategy for lowering acrylamide levels in rye crispbread.

Microbes and microbial strategies in carcinogenic polycyclic aromatic hydrocarbons remediation: a systematic review

Degradation, detoxification, or removal of the omnipresent polycyclic aromatic hydrocarbons (PAHs) from the ecosphere as well as their prevention from entering into food chain has never appeared simple. In this context, cost-effective, eco-friendly, and sustainable solutions like microbe-mediated strategies have been adopted worldwide. With this connection, measures have been taken by multifarious modes of microbial remedial strategies, i.e., enzymatic degradation, biofilm and biosurfactant production, application of biochar-immobilized microbes, lactic acid bacteria, rhizospheric-phyllospheric-endophytic microorganisms, genetically engineered microorganisms, and bioelectrochemical techniques like microbial fuel cell. In this review, a nine-way directional approach which is based on the microbial resources reported over the last couple of decades has been described. Fungi were found to be the most dominant taxa among the CPAH-degrading microbial community constituting 52.2%, while bacteria, algae, and yeasts occupied 37.4%, 9.1%, and 1.3%, respectively. In addition to these, category-wise CPAH degrading efficiencies of each microbial taxon, consortium-based applications, CPAH degradation-related molecular tools, and factors affecting CPAH degradation are the other important aspects of this review in light of their appropriate selection and application in the PAH-contaminated environment for better human-health management in order to achieve a sustainable ecosystem.

[Assessment of the in vitro effect of intra and extracellular extracts of Lactobacillus against genotoxicity and oxidative stress caused by acrylamide]

Introduction

Introduction: acrylamide is formed by the Maillard reaction and is found in many food products subjected to thermal processes, generating genotoxicity and DNA damage. Studies have reported that lactobacilli have the ability to generate compounds with antioxidant, antigenotoxic and antimutagenic activity, which is why the present work aims to evaluate the effect of Lactobacillus strains and their intra and extracellular extracts against genotoxicity and oxidative stress as caused by acrylamide. Methods: a strain of Lactobacillus casei Shirota and a strain of Lactobacillus reuteri NRRL B-14171 were used, both were cultured in MRS broth and subjected to mechanical and enzymatic treatments to obtain extra and intracellular extracts. Lymphocytes were cultured in RPMI medium. Lipid peroxidation was evaluated by TBARS and the antioxidant capacity was measured in the extra and intracellular extracts with the ABTS technique, also using a strain of Saccharomyces cerevisiae RC 212 as a model. The reduction of lipid peroxidation in lymphocytes was measured by TBARS and the reduction of genotoxicity by reducing the formation of micronuclei in lymphocytes. Results: both strains evaluated, as well as their intra and extracellular extracts, showed the ability to counteract oxidative stress and genotoxicity caused by acrylamide. Conclusion: the results found suggest that the use of intra and extracellular extracts of both strains could be an alternative to reduce the effects of genotoxicity and oxidative stress caused by acrylamide without the need for a viable structure.

Combined Effects of Acrylamide and Ochratoxin A on the Intestinal Barrier in Caco-2 Cells

Acrylamide (AA) and ochratoxin A (OTA) are contaminants that co-exist in the same foods, and may create a serious threat to human health. However, the combined effects of AA and OTA on intestinal epithelial cells remain unclear. The purpose of this research was to investigate the effects of AA and OTA individually and collectively on Caco-2 cells. The results showed that AA and OTA significantly inhibited Caco-2 cell viability in a concentration- and time-dependent manner, decreased transepithelial electrical resistance (TEER) values, and increased the lucifer yellow (LY) permeabilization, lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) levels. In addition, the levels of IL-1β, IL-6, and TNF-α increased, while the levels of IL-10 decreased after AA and OTA treatment. Western blot analysis revealed that AA and OTA damaged the intestinal barrier by reducing the expression of the tight junction (TJ) protein. The collective effects of AA and OTA exhibited enhanced toxicity compared to either single compound and, for most of the intestinal barrier function indicators, AA and OTA combined exposure tended to produce synergistic toxicity to Caco-2 cells. Overall, this research suggests the possibility of toxic reactions arising from the interaction of toxic substances present in foodstuffs with those produced during processing.

Study of Potential Synergistic Effect of Probiotic Formulas on Acrylamide Reduction

Acrylamide (AA) is a food processing contaminant commonly found in fried and baked food products. In this study, the potential synergistic effect of probiotic formulas in reducing AA was studied. Five selected probiotic strains (Lactiplantibacillus plantarum subsp. plantarum ATCC14917 (L. Pl.), Lactobacillus delbrueckii subsp. bulgaricus ATCC11842 (L. B.), Lacticaseibacillus paracasei subsp. paracasei ATCC25302 (L. Pa), Streptococcus thermophilus ATCC19258, and Bifidobacterium longum subsp. longum ATCC15707) were selected for investigating their AA reducing capacity. It was found that L. Pl. (10⁸ CFU/mL) showed the highest AA reduction percentage (43-51%) when exposed to different concentrations of AA standard chemical solutions (350, 750, and 1250 ng/mL). The potential synergistic effect of probiotic formulas was also examined. The result demonstrated a synergistic AA reduction effect by the probiotic formula: L. Pl. + L. B., which also showed the highest AA reduction ability among the tested formulas. A further study was conducted by incubating selected probiotic formulas with potato chips and biscuit samples followed by an in vitro digestion model. The findings demonstrated a similar trend in AA reduction ability as those found in the chemical solution. This study firstly indicated the synergistic effect of probiotic formulas on AA reduction and its effect was also highly strain-dependent.

Acrylamide adsorption by Enterococcus durans and Enterococcus faecalis: In vitro optimization, simulated digestive system and binding mechanism

Acrylamide is an unsaturated amide that forms in heated, starchy food products. This study was conducted to (1) examine the ability of 38 LAB to remove acrylamide; (2) optimize acrylamide removal of selected LAB under various conditions (pH, temperature, time and salt) using the Box-Behnken design (BBD); (3) the behavior of the selected LAB under the simulated gastrointestinal conditions; and (4) investigate the mechanism of adsorption. Out of the 38 LAB, Enterococcus durans and Enterococcus faecalis had the highest results in removing acrylamide, with 33 and 30% removal, respectively. Those two LAB were further examined for their binding abilities under optimized conditions of pH (4.5-6.5), temperature (32°C - 42°C), time (14-22 h), and NaCl (0-3% w/v) using BBD. pH was the main factor influenced the acrylamide removal compared to other factors. E. durans and E. faecalis exhibited acrylamide removal of 44 and 53%, respectively, after the in vitro digestion. Zeta potential results indicated that the changes in the charges were not the main cause of acrylamide removal. Transmission electron microscopes (TEM) results indicated that the cell walls of the bacteria increased when cultured in media supplemented with acrylamide.

Effects of sucrose and sodium chloride pretreatments on cassava and plantain chips fried in CLA-enriched soybean oil: an analysis of acrylamide content, microstructure, and other physical properties

The purpose of this research was to evaluate the effect of soaking plantain and cassava chips in sucrose or sodium chloride (NaCl) on their physical properties and acrylamide content after frying in Conjugated Linoleic Acid (CLA)-enriched soybean oil. Plantain and cassava were cut into 1 mm thick slices and soaked for 20 min in a solution of 30% sucrose or 3% NaCl at 40 °C, separately. Soaking in sucrose and NaCl had no significant effect (p < 0.05) on water loss, porosity, hardness, or microstructure. The acrylamide content ranged from 634 to 3177 µg/kg. The use of CLA-enriched oil had no significant effect (p < 0.05) on the physical characteristics evaluated in this study. Frying reduced the CLA content in the chips from an initial 31.8% in the oil to 22.25 and 21.69% in plantain and cassava chips, respectively.

Study of the Efficacy of Probiotic Bacteria to Reduce Acrylamide in Food and In Vitro Digestion

In this study, probiotic bacteria as a new post-processing approach to reduce acrylamide (AA) was investigated. The AA reduction ability of selected Lactobacillus strains and Bifidobacterium strains was demonstrated in (a) AA chemical solutions; (b) food matrices (biscuits and chips) and (c) in vitro digestion. The findings showed tested bacteria exhibited AA reduction ability which was probiotic strain-, AA concentration-, probiotic concentration-, incubation time- and pH-dependent. L. acidophilus LA 45 and B. longum ATCC 15707 (10⁹ CFU/mL) showed the highest AA reduction (86.85 and 88.85%, respectively) when exposed to 350 ng/mL AA solution for 8 h. The findings also demonstrated that AA reduction ability of selected probiotic strains was pH- and food matrix-dependent in both food matrices (9.45–22.15%) and in vitro digestion model (10.91–21.29%). This study showed probiotic bacteria can lower AA bioaccessibility under simulated digestion.

Acrylamide Elimination by Lactic Acid Bacteria: Screening, Optimization, In Vitro Digestion, and Mechanism

Acrylamide is a toxic compound that is formed in cooked carbohydrate-rich food. Baking, roasting, frying, and grilling are cooking methods that cause its formation in the presence of reducing sugar and asparagine. To prevent acrylamide formation or to remove it after its formation, scientists have been trying to understand acrylamide formation pathways, and methods of prevention and removal. Therefore, this study aimed to: (1) screen newly isolated LAB for acrylamide removal, (2) optimize conditions (pH, temperature, time, salt) of the acrylamide removal for selected LAB isolates using Box-Behnken design (BBD), (3) investigate the acrylamide removal abilities of selected LAB isolates under the in vitro digestion conditions using INFO-GEST2.0 model, and (4) explore the mechanism of the acrylamide removal using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS), zeta potential, transmission electron microscopy (TEM) measurement, and Fourier transform infrared spectroscopy (FTIR). Forty strains were tested in MRS broth, where Streptococcus lutetiensis and Lactiplantibacillus plantarum had the highest capability of acrylamide removal by 39% and 26%, respectively. To enhance the binding ability, both strains were tested under controlled conditions of pH (4.5, 5.5 and 6.5), temperature (32 °C, 37 °C and 42 °C), time (14, 18 and 22 h), and NaCl (0%, 1.5% and 3% w/v) using Box-Behnken design (BBD). Both strains removed more acrylamide in the range of 35-46% for S. lutetiensis and 45-55% for L. plantarum. After testing the bacterial binding ability, both strains were exposed to a simulated gastrointestinal tract environment, removing more than 30% of acrylamide at the gastric stage and around 40% at the intestinal stage. To understand the mechanism of removal, LAB cells were characterized via scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) and transmission electron microscopy (TEM) techniques. Cell charges were characterized by zeta potential and functional groups analyzed by Fourier transform infrared spectroscopy (FTIR). Results indicated that increasing cell wall thickness improved acrylamide adsorption capacity. Both FTIR and EDS indicated that functional groups C=O, C-O, and N-H were associated with acrylamide adsorption.

The Acrylamide Degradation by Probiotic Strain Lactobacillus acidophilus LA-5

Acrylamide is a harmful substance produced in thermal processed food; however, it can also be found in food with various additives. The aim of the study was to check whether the probiotic bacteria strain, Lactobacillus acidophilus LA-5 (LA5), can degrade acrylamide and hence reduce its concentration in foodstuff. Our results revealed that LA5 can degrade acrylamide and cause a decrease in its concentration, but only when other available carbon and nitrogen sources are lacking. In the presence of casein, lactose, milk fat or in whole cow’s milk, this ability disappeared. Acrylamide present in milk, however, modulated the bacteria metabolism by significantly enhancing lactic acid production by LA5 in milk (at conc. 100 µg/mL), while the production of acetic acid was rather reduced.

The Utilisation of Acrylamide by Selected Microorganisms Used for Fermentation of Food

Acrylamide (AA) present in food is considered a harmful compound for humans, but it exerts an impact on microorganisms too. The aim of this study was to evaluate the impact of acrylamide (at conc. 0–10 µg/mL) on the growth of bacteria (Leuconostoc mesenteroides, Lactobacillus acidophilus LA-5) and yeasts (Saccharomyces cerevisiae, Kluyveromyces lactis var. lactis), which are used for food fermentation. Moreover, we decided to verify whether these microorganisms could utilise acrylamide as a nutritional compound. Our results proved that acrylamide can stimulate the growth of L. acidophilus and K. lactis. We have, to the best of our knowledge, reported for the first time that the probiotic strain of bacteria L. acidophilus LA-5 is able to utilise acrylamide as a source of carbon and nitrogen if they lack them in the environment. This is probably due to acrylamide degradation by amidases. The conducted response surface methodology indicated that pH as well as incubation time and temperature significantly influenced the amount of ammonia released from acrylamide by the bacteria. In conclusion, our studies suggest that some strains of bacteria present in milk fermented products can exert additional beneficial impact by diminishing the acrylamide concentration and hence helping to prevent against its harmful impact on the human body and other members of intestinal microbiota.

Evaluation of acrylamide-removing properties of bacterial consortia under simulated gastrointestinal conditions

BACKGROUND

Previous studies have demonstrated the acrylamide-removing properties of probiotic monocultures; however, potential advantages of consortia over monocultures in reducing the dietary exposure to acrylamide have not been proven. Hence this work aims to assess the acrylamide (AA)-binding properties of bacterial consortia, consisting of either probiotic strains and / or representative bacteria of duodenal microbiota, exposed to simulated gastrointestinal conditions (SGC). The AA binding capacity of ten probiotic strains (PS) and six duodenal strains (NDS) was evaluated under different conditions; then, three different consortia (PS, NDS, and PS + NDS) were assessed under SGC.

RESULTS

Among individual PS, Bacillus coagulans GBI-30, Lactobacillus fermentum J23, L. pentosus J37 and J24, and L. casei Shirota, exhibited the highest AA-binding capacity (80-87%), while Bifidobacterium catenulatun ATCC27676, Streptococcus salivarius subsp. thermophilus ATCC19258, and S. gallolyticus ATCC9809 were the best (ca. 68%) NDS monocultures. Probiotic strain consortia showed higher (P < 0.05) AA binding capacity (> 90%) than monoculture bacteria. Conversely, individual NDS cultures displayed higher (P < 0.05) binding capacity than NDS consortia (60%). A significant reduction (P < 0.05) in AA removal capacity was observed when consortia were exposed to SGC, PS consortia being the most effective (> 60% removal).

CONCLUSION

These results suggest that consortia of specific PS could play an important role in reducing the intestinal availability of acrylamide. © 2021 Society of Chemical Industry.

The Ability of Probiotic Lactobacillus Strains in Removal of Benzo[a]pyrene: a Response Surface Methodology Study

In this study, the ability of various lactic acid bacteria was assessed in removing benzo[a]pyrene (BaP) from contaminated phosphate buffer saline (PBS). Response surface methodology (RSM) was performed using Box-Behnken design to investigate the effect of four independent variables including pH (5-7), incubation time (1-24 h), cell density (10⁷-10⁹ cfu/mL), and initial BaP concentration (5-15 mg/kg) at three levels to evaluate in vitro removal of BaP as response. The results showed that all the tested strains were able to remove BaP from PBS and this reduction was entirely strain-specific. Bifidobacterium lactis BB-12 followed by Lactobacillus casei TD10 exhibited the lowest binding ability while the highest binding rate was related to Lactobacillus acidophilus LA-5, Lactobacillus delbrueckii subsp. bulgaricus PTCC 1737, Lactobacillus casei TD4, and Lactobacillus brevis TD3, respectively. Cyclohexane washing weakened BaP-bacteria complex, while this complex was not significantly changed by PBS washing. The results showed that BaP binding rate was influenced by pH, cell density, time, and BaP concentration in linear and quadratic manners. Moreover, there were interactions between cell density and time as well as between time and BaP concentration. The highest BaP-binding rate by L. acidophilus LA-5 was 10 ppm of BaP concentration, pH = 5, cell density of 10⁹ cfu/mL, and an incubation period of 24 h. It can be concluded that a range of pH, time, and microbial population is required to obtain maximum binding efficiency for BaP based on the concentration of the toxin and the species of the bacteria.

The In Vitro Adsorption Ability of Lactobacillus acidophilus NCFM to Benzo(a)pyrene in PM2.5

The objective of this work was to explore the ability of lactic acid bacteria strains to bind benzo(a)pyrene (B(a)P) existing in PM_2.5. In this study, we examined the ability of Lactobacillus acidophilus NCFM to bind B(a)P in the simulated PM_2.5 environment. Among the tested 5 strains, Lactobacillus acidophilus NCFM exhibited the best capacity to bind B(a)P, and its B(a)P binding percentage was 60.00%. Simulations of organic and inorganic systems which represent PM_2.5 indicated that B(a)P could be absorbed by strain L. acidophilus NCFM. For the inorganic system of pH 5, L. acidophilus NCFM bound 92.74% B(a)P with a cell concentration of 1 × 10¹⁰ cfu/mL at 37°C for 8 hr. Regarding the organic system with pH 6, 73.00% B(a)P was bound by strain L. acidophilus NCFM after this bacterium was incubated at 37°C for 10 min. A quick B(a)P binding by this probiotic bacterium took place in the organic system. The removal of B(a)P from PM_2.5 was significantly related to incubation time, cultivation temperature, pH, and cell concentration. Thus, our finding shows that long-term consumption of L. acidophilus NCFM is beneficial for the reduction of B(a)P towards the population who are exposed to PM_2.5, although the ability of this bacterium to adsorb B(a)P is partly affected by the differences in the origin of PM_2.5.

Protective role of lactic acid bacteria and yeasts as dietary carcinogen-binding agents - a review

The importance of food contaminants in the link between diet and cancer has been widely demonstrated. Therefore, different physical and chemical strategies for the control of human exposure to such dietary carcinogens has been explored; however, most of these strategies are complex, costly, and have low efficiency which limited their applications. Hence, microbiological methods have been receiving more attention. Recent in vitro and in vivo studies have indicated that lactic acid bacteria (LAB) and yeast may act as dietary carcinogen-binding agents. This review describes the promising protective role of strains belonging mainly to the Lactobacillus, Bifidobacterium and Saccharomyces genera by acting as dietary carcinogen-binding agents. This property suggests that these microorganisms may have a protective role by reducing the bioaccessibility of dietary carcinogens, thereby decreasing their toxic effects. The mechanisms by which the binding process takes place have not been completely elucidated; thus, the possible underlying mechanisms and factors influencing carcinogens-binding will be addressed.

Is Acrylamide as Harmful as We Think? A New Look at the Impact of Acrylamide on the Viability of Beneficial Intestinal Bacteria of the Genus Lactobacillus

The impact of acrylamide (AA) on microorganisms is still not clearly understood as AA has not induced mutations in bacteria, but its epoxide analog has been reported to be mutagenic in Salmonella strains. The aim of the study was to evaluate whether AA could influence the growth and viability of beneficial intestinal bacteria. The impact of AA at concentrations of 0–100 µg/mL on lactic acid bacteria (LAB) was examined. Bacterial growth was evaluated by the culture method, while the percentage of alive, injured, and dead bacteria was assessed by flow cytometry after 24 h and 48 h of incubation. We demonstrated that acrylamide could influence the viability of the LAB, but its impact depended on both the AA concentration and the bacterial species. The viability of probiotic strain Lactobacillus acidophilus LA-5 increased while that of Lactobacillus plantarum decreased; Lactobacillus brevis was less sensitive. Moreover, AA influenced the morphology of L. plantarum, probably by blocking cell separation during division. We concluded that acrylamide present in food could modulate the viability of LAB and, therefore, could influence their activity in food products or, after colonization, in the human intestine.

Occurrence and Dynamism of Lactic Acid Bacteria in Distinct Ecological Niches: A Multifaceted Functional Health Perspective

Lactic acid bacteria (LAB) are representative members of multiple ecosystems on earth, displaying dynamic interactions within animal and plant kingdoms in respect with other microbes. This highly heterogeneous phylogenetic group has coevolved with plants, invertebrates, and vertebrates, establishing either mutualism, symbiosis, commensalism, or even parasitism-like behavior with their hosts. Depending on their location and environment conditions, LAB can be dominant or sometimes in minority within ecosystems. Whatever their origins and relative abundance in specific anatomic sites, LAB exhibit multifaceted ecological and functional properties. While some resident LAB permanently inhabit distinct animal mucosal cavities, others are provided by food and may transiently occupy the gastrointestinal tract. It is admitted that the overall gut microbiome has a deep impact on health and diseases. Here, we examined the presence and the physiological role of LAB in the healthy human and several animal microbiome. Moreover, we also highlighted some dysbiotic states and related consequences for health, considering both the resident and the so-called "transionts" microorganisms. Whether LAB-related health effects act collectively or follow a strain-specificity dogma is also addressed. Besides the highly suggested contribution of LAB to interplay with immune, metabolic, and even brain-axis regulation, the possible involvement of LAB in xenobiotic detoxification processes and metal equilibrium is also tackled. Recent technological developments such as functional metagenomics, metabolomics, high-content screening and design in vitro and in vivo experimental models now open new horizons for LAB as markers applied for disease diagnosis, susceptibility, and follow-up. Moreover, identification of general and more specific molecular mechanisms based on antioxidant, antimicrobial, anti-inflammatory, and detoxifying properties of LAB currently extends their selection and promising use, either as probiotics, in traditional and functional foods, for dedicated treatments and mostly for maintenance of normobiosis and homeostasis.

Evaluation of acrylamide-removing properties of two Lactobacillus strains under simulated gastrointestinal conditions using a dynamic system

The aim of this study was to evaluate the capability of Lactobacillus reuteri NRRL 14171 and Lactobacillus casei Shirota to remove dietary acrylamide (AA) under simulated gastrointestinal conditions using a dynamic system. The effects of different AA levels or bacteria concentration on toxin removal by Lactobacillus strains were assessed. Thereafter, AA-removing capability of bacteria strains under either fasting or postprandial simulated gastrointestinal conditions was evaluated. Commercial potato chips were analyzed for their AA content, and then used as a food model. Average AA content (34,162μg/kg) in potato chips exceeded by ca. 34-fold the indicative values recommended by the EU. Toxin removal ability was dependent on AA content and bacterial cell concentration. A reduction on bacterial viability was observed in the food model and at the end of both digestive processes evaluated. However, bacteria survived in enough concentrations to remove part of the toxin (32-73%). Both bacterial strains were able to remove AA under different simulated gastrointestinal conditions, being L. casei Shirota the most effective (ca. 70% removal). These findings confirmed the risk of potato chips as dietary AA exposure for consumers, and that strains of the genus Lactobacillus could be employed to reduce the bioavailability of dietary AA.

A review of the interactions between acrylamide, microorganisms and food components

Acrylamide (AA) and its metabolites have been recognized as potential carcinogens, but also they can cause other negative symptoms in human or animal organisms and therefore this class of chemical compounds has attracted a lot of attention.

Inulin supplementation during gestation mitigates acrylamide-induced maternal and fetal brain oxidative dysfunctions and neurotoxicity in rats

Accumulating evidence suggests that the developing brain is more susceptible to a variety of chemicals. Recent studies have shown a link between the enteric microbiota and brain function. While supplementation of non-digestible oligosaccharides during pregnancy has been demonstrated to positively influence human health mediated through stimulation of beneficial microbiota, our understanding on their neuromodulatory propensity is limited. In the present study, our primary focus was to examine whether supplementation of inulin (a well known fructan) during gestation can abrogate acrylamide (ACR)-induced oxidative impairments and neurotoxicity in maternal and fetal brain of rats. Initially, in a dose-determinative study, we recapitulated the impact of ACR exposure during gestation days (GD 6-19) on gestational parameters, extent of oxidative impairments in brain (maternal/fetal), cholinergic function and neurotoxicity. Subsequently, pregnant rats orally (gavage) administered with inulin (IN, 2 g/kg/day in two equal installments) supplements during gestation days (GD 0-19) were exposed to ACR (200 ppm) in drinking water. IN supplements significantly attenuated ACR-induced changes in exploratory activity (reduced open field exploration) measured on GD 14. Further, IN restored the placental weights among ACR exposed dams. Analysis of biochemical markers revealed that IN supplements effectively offset ACR associated oxidative stress not only in the maternal brain, but in the fetal brain as well. Elevated levels of protein carbonyls in maternal brain regions were completely normalized with IN supplements. More importantly, IN supplements significantly augmented the number of Bifidobacteria in the cecum of ACR rats which correlated well with the neurorestorative effect as evidenced by restored dopamine levels in the maternal cortex and fetal brain acetylcholinesterase activity among ACR-exposed dams. Further, IN supplements also conferred significant protection against mitochondrial dysfunction induced by ACR in both milieus. Although the precise mechanism/s by which IN supplements during pregnancy attenuate ACR induced neurotoxic impact merits further investigations, we hypothesize that it may mediate through enhanced enteric microbiota and abrogation of oxidative stress. Further, our study provides an experimental approach to explore the neuroprotective role of prebiotic oligosaccharides during pregnancy in reducing the adverse impact of developmental neurotoxicants.