Mycotoxin detoxification of food by lactic acid bacteria

Publisher Copyright: © 2021, The Author(s).Today, a few hundred mycotoxins have been identified and the number is rising. Mycotoxin detoxification of food and feed has been a technically uphill task for the industry. In the twenty-first century, the public demand is healthy food with minimum use of chemicals and preservatives. Among all the fungal inhibition and mycotoxin detoxification methods so far developed for food, biopreservation and biodetoxification have been found safe and reliable. Nowadays, lactic acid bacteria (LAB) are of great interest as biological additives in food owing to their Generally Recognized as Safe (GRAS) classification and mycotoxin detoxification capability. The occurrence of fungul growth in the food chain can lead to health problems such as mycotoxicosis and cancer to humans due to producing mycotoxins such as aflatoxins. Biopreservation is among the safest and most reliable methods for inhibition of fungi in food. This review highlights the great potential of LAB as biodetoxificant by summarizing various reported detoxification activities of LAB against fungal mycotoxins released into foods. Mechanisms of mycotoxin detoxification, also the inherent and environmental factors affecting detoxifying properties of LAB are also covered.Peer reviewe

Evaluation of Anti-Fungal Activity of Chitosan and Its Effect on the Moisture Absorption and Organoleptic Characteristics of Pistachio Nuts

Pistachio is one of the main export products of Iran and Iran is one of the largest producer and exporter of pistachio in the world. Unfavourable environmental conditions during storage, causes a sharp drop in quality of product through musty and toxin production, especially aflatoxin by Aspergillus flavus and Aspergillus parasiticus, Absorption of foreign odors and moisture, Tissue destruction of undesirable flavour. The aim of this study was to study the anti-fungal activity of chitosan and its effect on the organoleptic characteristics of pistachio nuts.  Therefore, using acetic acid 1% V / V, chitosan concentrations of 0.5%, 1% and 1.5 % V/W was prepared and pistachios were coated by these solutions. Also acetic acid at concentration 1% without chitosan was used as a treatment for coating to determine the antimicrobial effect of acetic acid. The results showed that chitosan significantly (p <0.05) inhibited the growth of the Aspergillus and its effect was increased with increased concentration. Chitosan also prevented moisture absorption and weight change in pistachio nuts, while chitosan concentration showed no significant effect on moisture absorption and weight change of pistachio nuts. Chitosan 1.5% had a significant effect (p <0.05) on the flavour of pistachio, but other concentrations had no effect. However, chitosan in general had no significant effect (p <0.05) on color, texture and acceptability of pistachio nuts

Optimization of Gamma Aminobutyric Acid Production from Various Protein Hydrolysates by Lactiplantibacillus plantarum MCM4

Background and Objective: Gamma aminobutyric acid (GABA) is a non-protein amino acid with various physiological properties that is used as synthetic drugs for curing anxiety, acute stress, and hypertension. In the recent years, producing the GABA-enriched foods and supplements via biological methods has gained much attention. Material and Methods: In this study, at first, one factor at a time (OFAT) approach was used to study the effect of various kinds of protein hydrolysates (soy protein isolate (SPI), whey protein concentration (WPC) and casein) at different concentrations, fermentation time (24 to 72h) and inoculum size (1, 3, and 5% v/v) on GABA synthesis. Then, the most effective parameters i.e., soy protein hydrolysate (SPH) concentration, inoculum size, and fermentation time were further employed by central composite design (CCD)-based response surface methodology (RSM) for GABA synthesis by Lactobacillus plantarum MCM4. Results and Conclusion: Among different protein hydrolysates, SPH was found to be more suitable for GABA synthesis. Moreover, higher GABA content was obtained when soy protein with extended enzymatic hydrolysis (SPH6) was used as the substrate. The polynomial mathematic model could predict the GABA synthesis successfully. The optimization using CCD indicated that the maximum GABA syntehsis yield (19.387 mg GABA/100 mL) was achieved under optimium conditions (fermentaion time of 28.99 h, inoculum size of 3.65% v/v, and SPH6 concnetration of 3.89% w/v). Overall, L. plantarum MCM4 was found to be a novel LAB species to produce GABA from inexpensive sources

Antifungal Preservation of Food by Lactic Acid Bacteria

Fungal growth and consequent mycotoxin release in food and feed threatens human health, which might even, in acute cases, lead to death. Control and prevention of foodborne poisoning is a major task of public health that will be faced in the 21st century. Nowadays, consumers increasingly demand healthier and more natural food with minimal use of chemical preservatives, whose negative effects on human health are well known. Biopreservation is among the safest and most reliable methods for inhibiting fungi in food. Lactic acid bacteria (LAB) are of great interest as biological additives in food owing to their Generally Recognized as Safe (GRAS) classification and probiotic properties. LAB produce bioactive compounds such as reuterin, cyclic peptides, fatty acids, etc., with antifungal properties. This review highlights the great potential of LAB as biopreservatives by summarizing various reported antifungal activities/metabolites of LAB against fungal growth into foods. In the end, it provides profound insight into the possibilities and different factors to be considered in the application of LAB in different foods as well as enhancing their efficiency in biodetoxification and biopreservative activities

Antifungal Preservation of Food by Lactic Acid Bacteria

Fungal growth and consequent mycotoxin release in food and feed threatens human health, which might even, in acute cases, lead to death. Control and prevention of foodborne poisoning is a major task of public health that will be faced in the 21st century. Nowadays, consumers increasingly demand healthier and more natural food with minimal use of chemical preservatives, whose negative effects on human health are well known. Biopreservation is among the safest and most reliable methods for inhibiting fungi in food. Lactic acid bacteria (LAB) are of great interest as biological additives in food owing to their Generally Recognized as Safe (GRAS) classification and probiotic properties. LAB produce bioactive compounds such as reuterin, cyclic peptides, fatty acids, etc., with antifungal properties. This review highlights the great potential of LAB as biopreservatives by summarizing various reported antifungal activities/metabolites of LAB against fungal growth into foods. In the end, it provides profound insight into the possibilities and different factors to be considered in the application of LAB in different foods as well as enhancing their efficiency in biodetoxification and biopreservative activities

The Combined Effect of Carum copticum (Ajwain) and Foeniculum vulgare (Fennel) Essential Oils on Escherichia coli and Clostridium sporogenes Using Checkerboard Assay

Increasing awareness of the adverse effects of chemical preservatives on health has led to an increased tendency to use natural preservatives, especially herbal essential oils in pharmaceutical and food products. Carum copticum (Ajwain) and Foeniculum vulgare (Fennel) are among the aromatic medicinal plants that can be used in this regard. In this study, the agar diffusion method was used to evaluate and compare the antimicrobial effects of the herbal essential oils in question and the dilution method in the liquid medium was also used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The checkerboard assay was used to evaluate the interaction between the herbal essential oils of Ajwain and Fennel and to determine the fractional inhibitory concentration. The results showed that the MIC of Ajwain and Fennel herbal essential oils against Escherichia coli was 1562.5 μg/ml and 12500 μg/ml, respectively, and in the case of Clostridium sporogenes this value was 1562.5 μg/ml and 50000 μg /ml, respectively. Calculation of fractional inhibitory concentration (FIC index) indicated that there was no interaction between the herbal essential oils of two plants against both bacteria in question. In general, the absence of synergistic and antagonistic interactions between the Ajwain and Fennel herbal essential oils can be related to the identically-affected sites of these essential oils in Escherichia coli and Clostridium sporogenes. Also, the results obtained through the identification of herbal essential oils composition by GC/MS showed that the main components of Ajwain were Thymol (49.96%), p-cymane (22.73%) and γ-Terpinene (15.32%) and in case of Fennel these components were Trans-anethole (63.88%), Estragole (9.97%), limonene (7.65%) and fenchone (5.72%)

Psychobiotics and Brain-Gut Microbiota Axis

Fermented foods containing probiotic bacteria have been used for many years to improve the health or treatment of some diseases. Nowadays, the Therapeutic properties of probiotics are becoming more and more obvious to everyone, insofar as in recent years, more attention has been paid to the potential relation between gut microbiota and mental health. Several studies have shown that intestinal microbiota play some roles in development and function of brain as well as psychiatric parameters such as sleep, appetite, mood and perception through production of active neural molecules. These findings, in turn had led to further research on new therapies for the resolution of mental disorders through changing and modification of intestinal microflora using a new therapeutic group called psychobiotics. Psychobiotics are probiotic bacteria that if consumed in adequate dosage, affect the function of the intestines and brain and reduce the symptoms of psychiatric illness

Lactobacillus Species from Iranian Jug Cheese: Identification and Selection of Probiotic Based on Safety and Functional Properties

Background and Objective: Traditional fermented products are appropriate sources for the isolation of indigenous bacteria with probiotic characteristics and potential similar or better than commercial probiotics. In this study, Lactobacillus species were isolated from jug cheese, a type of Iranian traditional cheese, and their potential probiotic characteristics were studied. Material and Methods: Study of the probiotic species included hemolytic activity, antibiotic susceptibility, inhibitory activity against pathogenic bacteria, low pH and bile salts tolerance, viability in gastrointestinal tract conditions and adhesion ability to HT-29 cells. Results and Conclusion: Results showed that the isolates included no hemolytic activity and were susceptible or intermediate susceptibility to most antibiotics. Of four isolates, Lacto-bacillus plantarum KMJC4 showed the strongest antibacterial activity (MIC = 6.25 mg ml-1) against Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus and Salmonella enterica subsp. enterica serovar Typhimurium. All the isolates, except Lactobacillus curvatus KMJC3, preserved their viability after transition through the simulated gastrointestinal tract conditions above 106 CFU ml-1. Lactobacillus acidipiscis KMJC2 and Lactobacillus plantarum KMJC4 showed the lowest and the highest adhesion rates to HT-29 cells with 3.55 and 6.80 Log10 CFU ml-1 (42.51 and 71.35%), respectively. Lactobacillus plantarum KMJC4 included a better bacterial inhibitory activity and adhesion to HT-29 cells than that Lactobacillus rhamnosus GG did as control. Lactobacillus brevis KMJC1 demonstrated appropriate probiotic characteristics such as antibacterial activity, viability in low pH, bile salts and gastrointestinal tract conditions and adhesion capability to HT-29 cells. In conclusion, Lactobacillus plantarum KMJC4 and Lactobacillus brevis KMJC1 were introduced as probiotic capable strains. Based on the results from the current in vitro study, finding probiotics with similar or better characteristics than commercial probiotics within indigenous bacteria is quite possible. In vivo assessment of the bacteria can be considered in future studies, investigating using possibilities of these bacteria in food industries to produce functional fermented foods and in pharmaceutical industries in form of probiotic capsules. Conflict of interest: The authors declare no conflict of interest