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

Abstract

Acrylamide is a chemical naturally formed in certain foods during processing and/or cooking at high temperatures. Scientific studies have indicated that significant dietary exposure to acrylamide poses a risk for several types of cancer and may have harmful effects to the nervous system in humans. Hence, methods that can contribute to reduce acrylamide exposure in foods are needed. Considering that specific lactic acid bacteria are able to remove a variety of foodborne mutagens, namely heterocyclic amines, lead, cadmium and aflatoxin B1 by a binding mechanism, the aim of the present study was to assess the ability of fourteen lactic acid strains to remove acrylamide in vitro. Acrylamide binding ability ranged from 11.89 to 29.12%, and it was found to be both concentration‐ and strain‐dependent. Lactobacillus reuteri Northern Regional Research Laboratory 14171 (USDA‐ARS) and Lactobacillus casei Shirota were the most efficient binders (24.01 and 24.95%, respectively) after 12 h of incubation using an acrylamide concentration of 5 μg/mL. Acrylamide binding was also pH‐dependent, and the bacterial–toxin complex exhibited high stability assessed by repeated washings. The results of this work proposes for the first time the acrylamide binding ability in vitro of selected lactic acid bacteria, which suggest their potential for detoxification of the food contaminant acrylamide. Practical Applications All bacteria tested proved capable to bind acrylamide efficiently and rapidly in phosphate buffer saline; hence, these bacteria could be an effective decontamination mechanism against foodborne acrylamide along the gastrointestinal tract. It is reasonable to believe that during the first contact of acrylamide‐contaminated food with lactic acid bacteria in the mouth, the place where digestion starts and the pH is favorable for the toxin–bacteria interaction, a portion of acrylamide may be bound by the bacteria. Moreover, as both toxin and bacteria navigate through the digestive tract, the variations in pH may cause mutagen binding at different extents until it reaches the small intestine (alkaline pH), the site where absorption of food components is the highest, and the pH value is favorable. Therefore, this kind of bacteria could play a protective role by reducing the bioavailability of foodborne acrylamide.

Potential Anticarcinogenic Effects of Lactic Acid Bacteria and Probiotics in Detoxification of Process-Induced Food Toxicants

“…At 0 hour, the amount of bound acrylamide was from 11.89 to 29.13%, depending on the strains and the maximum binding was observed in strains AC and SHI. It was proposed that binding was a rapid process and occurred passively on the bacterial surface (88). This is in accordance with the findings by Hernandez-Mendoza et al that observed aflatoxin B1 bound 15 to 58% at 0 hour (89).…”

“…The binding ability of strains was investigated at different pH levels (3, 5 and 8). The maximum binding at pH 8 was observed in the strain L334 while at pH 3, a substantial reduction in binding ability occurred (88). Similarly, Zhang et al (45) reported a more binding of pyrolyzed mutagen at pH 6 -7 as well as Hernandez-Mendoza et al that implied, L. reuteri NRRL 14171 and L. casei Shirota bound more effectively at pH 7 than pH 8 (89).…”

“…The presence of the lower amount of glucose, D-alanine or teichoic acid caused more binding of acrylamide to the cell wall of bacteria. H-bonds may develop between carbonyl oxygen and the amino group between adjacent acrylamide and D-Alanine directly attached to position D-4 (L-2) of ribitol (88). Furthermore, the amine group of D-alanine might react with acrylamide units by means of a Michael addition reaction (91).…”

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

“…The chromatographic procedure was followed according to previously reported by Serrano-Niño et al (2014) Briefly, the HPLC System (Waters®, Milford, MA) used for AA quantification consisted of a Waters® 600 quaternary pump with a solvent delivery system, a C18 ODS Spheri-5 column (220 nm x 4.6 mm, Supelco®, Belefonte, PA), and an UV-visible detector (Waters® 2487) set at 195 nm. All data were collected and processed using the Empower data acquisition software (Waters ® ).…”

A Combination Supplement of Fructo- and Xylo-Oligosaccharides Significantly Abrogates Oxidative Impairments and Neurotoxicity in Maternal/Fetal Milieu Following Gestational Exposure to Acrylamide in Rat

“…Hence based on our finding that prebiotic supplements enhance the levels of Bifidobacteria among ACR exposed dams, we speculate this could play a predominant role in the observed protective effect. Further, it may also related to the reported in vitro potential of specific Lactobacillus strains to bind the neurotoxin ACR which may result in increased detoxification [77]. Accordingly it is likely that the prebiotic supplements may affect the bioavailability of ACR.…”