Functional and health-promoting properties of probiotics' exopolysaccharides; isolation, characterization, and applications in the food industry.

Exopolysaccharides (EPS) are extracellular sugar metabolites/polymers of some slim microorganisms and, a wide variety of probiotics have been broadly investigated for their ability to produce EPS. EPS originated from probiotics have potential applications in food, pharmaceutical, cosmetology, wastewater treatment, and textiles industries, nevertheless slight is recognized about their function. The present review purposes to comprehensively discuss the structure, classification, biosynthesis, extraction, purification, sources, health-promoting properties, techno-functional benefits, application in the food industry, safety, toxicology, analysis, and characterization methods of EPS originated from probiotic microorganisms. Various studies have shown that probiotic EPS used as stabilizers, emulsifiers, gelling agents, viscosifiers, and prebiotics can alter the nutritional, texture, and rheological characteristics of food and beverages and play a major role in improving the quality of these products. Numerous studies have also proven the beneficial health effects of probiotic EPS, including antioxidant, antimicrobial, anti-inflammatory, immunomodulatory, anticancer, antidiabetic, antibiofilm, antiulcer, and antitoxin activities. Although the use of probiotic EPS has health effects and improves the organoleptic and textural properties of food and pharmaceutical products and there is a high tendency for their use in related industries, the production yield of these products is low and requires basic studies to support their products in large scale.

Health-promoting properties of Saccharomyces cerevisiae var. boulardii as a probiotic; characteristics, isolation, and applications in dairy products.

Saccharomyces cerevisiae var. boulardii (S. boulardii) has been isolated from lychee (Litchi chinensis), mangosteen fruit, kombucha, and dairy products like kefir. Dairy products containing S. boulardii have been revealed to possess potential probiotic activities owing to their ability to produce organic acids, essential enzymes, vitamins, and other important metabolites such as vanillic acid, phenyl ethyl alcohol, and erythromycin. S. boulardii has a wide spectrum of anti-carcinogenic, antibacterial antiviral, and antioxidant activity, and is known to reduce serum cholesterol levels. However, this yeast has mainly been prescribed for prophylaxis treatment of gastrointestinal infectious diseases, and stimulating the immune system in a number of commercially available products. The present comprehensive review article reviews the properties of S. boulardii related to their use in fermented dairy foods as a probiotic microorganism or starter culture. Technical aspects regarding the integration of this yeast into the dairy foods matrix its health advantages, therapeutic functions, microencapsulation, and viability in harsh conditions, and safety aspects are highlighted.

A study on the aflatoxin M1 rate and seasonal variation in pasteurized cow milk from northwestern Iran.

Present study aims to assess aflatoxin M1 (AFM1) contamination in 100 samples of pasteurized milk which were conventionally gathered during spring, summer, autumn, and winter from supermarkets located in Maragheh city of northwestern Iran. Samples were evaluated for AFM1 with a high-performance liquid chromatography (HPLC) method and with fluorimetric detection. The results showed that approximately 44% (11.25) of samples in winter, 32% (8.25) of samples in spring, 24% (6.25) of samples in summer, and 20% (5.25) of samples in autumn had AFM1 concentrations that exceeded the limit (0.05 µg/l) set by the European, Codex Alimentarius Commission and Iran standards. According to the statistical analysis of the data, there was no significant variation between the mean content of AFM1 during different seasons (P = 0.076). The results of our study suggest a high level of contamination of AFM1 in pasteurized milk in all seasons which may be due to the fact that milk supply for dairy factories is provided from dairy farms that are low in livestock feed quality. In Iran, pasteurized milk is consumed more than other milk products by all age groups. The total daily aflatoxin intake from contaminated milk and possibly other food products will be a significant risk to public health.

Health Benefits and Safety of Postbiotics Derived from Different Probiotic Species.

Nowadays, the usage of probiotics in the food industry has become common. It has been proven that probiotics have many health benefits, such as adjusting the intestinal microbiome, boosting the immune system, and enhancing anti-inflammatory and anti-cancer activities. However, in recent years, some concerns have arisen about the consumption of probiotics, especially in vulnerable populations such as elderly, infants, and people with underlying diseases. As a result, finding a new alternative to probiotics that has the same function as probiotics and is safer has been prioritized. In recent years, postbiotics have been introduced as a great replacement for probiotics. However, the safety of these compounds is not exactly confirmed due to the limited in vivo research. In this review, the definition, classification, activities, limitations, and some advantages of postbiotics over probiotics are discussed. Finally, the limited published data about the safety of postbiotics is summarized.

Malva neglecta seed polysaccharide mucilage coating enriched by the Lactobacillus brevis TD4 postbiotics: A promising strategy to promote the shelf life of fresh beef.

The need for bioactive-incorporated biodegradable packaging products is growing due to the desire to achieve food goods that have a longer shelf life and enhanced safety. The current study set out to create an edible coating using Malva neglecta seed polysaccharide mucilage (MNSM) containing Lactobacillus brevis TD4-derived postbiotics (PLB), and assess how well the PLB-MNSM edible coating preserved beef slices over a 12-day period of refrigeration. PLB was rich in fatty acids, organic heteropolycyclic compounds, monoterpene and cyclohexanol derivative, prenol lipids, ester compounds, and alpha-CH2-containing aldehyde with significant antimicrobial and antioxidant activities. By adding it to the edible coating at 0, 5, 10, and 15 % v/v, it successfully prevented the proliferation of microbial agents (total viable count, psychrotrophic count, Staphylococcus aureus, Escherichia coli, total coliform bacteria count, and fungi) as well as the oxidation of lipids (thiobarbituric and peroxide values) in beef samples. The samples' pH value, hardness, and moisture content were all more successfully sustained when PLB preparation was applied to the coating solution (P < 0.05). The edible coating consisting of PLB effectively maintained the meat color (L*, a*, b*) and sensory properties. Additionally, the bioactive edible coating comprised of MNSM and PLB, specifically MNSM-15 % PLB, significantly prevented the quality deterioration of beef samples and prolonged the shelf-life of the meat to over 12 days. The outcomes indicated that the MNSM-PLB edible coating has the capacity to be utilized as an antibacterial and antioxidant-rich packing material, hence enhancing the shelf life of meat-based goods.

Gut Microbiota and Polycystic Ovary Syndrome (PCOS): Understanding the Pathogenesis and the Role of Probiotics as a Therapeutic Strategy.

Polycystic ovary syndrome (PCOS) is one of the most common disorders among women in modern societies. A variety of factors can contribute to the development of PCOS. These women often exhibit high insulin resistance (IR), hyperandrogenism, irregular periods, and infertility. Dysbiosis of the gut microbiota (GMB) in women with PCOS has attracted the attention of many researchers. Porphyromonas spp., B. coprophilus, and F. prausnitzii are found in higher numbers in the gut of women with PCOS. Short-chain fatty acids (SCFAs), produced by the intestinal microbiota through fermentation, play an essential role in regulating metabolic activities and are helpful in reducing insulin resistance and improving PCOS symptoms. According to studies, the bacteria producing SCFAs in the gut of these women are less abundant than in healthy women. The effectiveness of using probiotic supplements has been proven to improve the condition of women with PCOS. Daily consumption of probiotics improves dysbiosis of the intestinal microbiome and increases the production of SCFAs.

Extrusion and Co-extrusion: A Technology in Probiotic Encapsulation with Alternative Materials.

Encapsulation, in particular extrusion and co-extrusion, is a common practice to protect probiotics from the harsh conditions of the digestive tract as well as processing. Hydrocolloids, including proteins and carbohydrates, natural or modified, are a group of ingredients used as the wall material in extrusion. Hydrocolloids, due to their specific properties, can significantly improve the probiotic survivability of the final powder during the microencapsulation process and storage. The present article will discuss the different kinds of hydrocolloids used for microencapsulation of probiotics by extrusion and co-extrusion, along with new sources of novel gums and their potential as wall material.

A comprehensive review of the application of probiotics and postbiotics in oral health.

Oral diseases are among the most common diseases around the world that people usually suffer from during their lifetime. Tooth decay is a multifactorial disease, and the composition of oral microbiota is a critical factor in its development. Also, Streptococcus mutans is considered the most important caries-causing species. It is expected that probiotics, as they adjust the intestinal microbiota and reduce the number of pathogenic bacteria in the human intestine, can exert their health-giving effects, especially the anti-pathogenic effect, in the oral cavity, which is part of the human gastrointestinal tract. Therefore, numerous in vitro and in vivo studies have been conducted on the role of probiotics in the prevention of tooth decay. In this review, while investigating the effect of different strains of probiotics Lactobacillus and Bifidobacteria on oral diseases, including dental caries, candida yeast infections, periodontal diseases, and halitosis, we have also discussed postbiotics as novel non-living biological compounds derived from probiotics.

The role of probiotics and prebiotics in modulating of the gut-brain axis.

Pro-and prebiotics have been indicated to modulate the gut-brain axis, which have supportive impacts on central nervous systems, and decrease or control the incidence of some mental disorders such as depression, anxiety, autism, Schizophrenia, and Alzheimer's. In this review, complex communications among microbiota, gut, and the brain, and also recent scientific findings of the impacts and possible action mechanisms of pro-and prebiotics on mental disorders have been discussed. The results have shown that pro-and prebiotics can improve the function of central nervous system and play an important role in the prevention and treatment of some brain disorders; however, in order to prove these effects conclusively and firmly and to use these compounds in a therapeutic and supportive way, more studies are needed, especially human studies/clinical trials.

Metal-binding peptides and their potential to enhance the absorption and bioavailability of minerals.

Minerals including calcium, iron, zinc, magnesium, and copper have several human nutritional functions due to their metabolic activities. Body tissues require sufficient levels of a variety of micronutrients to maintain their health. To achieve these micronutrient needs, dietary consumption must be adequate. Dietary proteins may regulate the biological functions of the body in addition to acting as nutrients. Some peptides encoded in the native protein sequences are primarily responsible for the absorption and bioavailability of minerals in physiological functions. Metal-binding peptides (MBPs) were discovered as potential agents for mineral supplements. Nevertheless, sufficient studies on how MBPs affect the biological functions of minerals are lacking. The hypothesis is that the absorption and bioavailability of minerals are significantly influenced by peptides, and these properties are further enhanced by the configuration and attribute of the metal-peptide complex. In this review, the production of MBPs is discussed using various key parameters such as the protein sources and amino acid residues, enzymatic hydrolysis, purification, sequencing and synthesis and in silico analysis of MBPs. The mechanisms of metal-peptide complexes as functional food ingredients are elucidated, including metal-peptide ratio, precursors and ligands, complexation reaction, absorbability and bioavailability. Finally, the characteristics and application of different metal-peptide complexes are also described.

The Role of Probiotics in Improving Food Safety: Inactivation of Pathogens and Biological Toxins.

Currently, many advances have been made in avoiding food contamination by numerous pathogenic and toxigenic microorganisms. Many studies have shown that different probiotics, in addition to having beneficial effects on the host's health, have a very good ability to eliminate and neutralize pathogens and their toxins in foods which leads to enhanced food safety. The present review purposes to comprehensively discuss the role of probiotics in improving food safety by inactivating pathogens (bacterial, fungal, viral, and parasite agents) and neutralizing their toxins in food products. Some recent examples in terms of the anti-microbial activities of probiotics in the body after consuming contaminated food have also been mentioned. This review shows that different probiotics have the potential to inactivate pathogens and neutralize and detoxify various biological agents in foods, as well as in the host body after consumption.

Gut Microbiota Might Act as a Potential Therapeutic Pathway in COVID-19.

It has been very recently suggested that individuals with chronic gut inflammation are highly susceptible to COVID-19. They constitute the serious cases of COVID-19, in which inflammatory cytokine storm is observed. On the contrary, the healthy gut microbiota is linked with low chronic gut and systemic inflammation. This raises the idea that maintenance of the healthy gut microbiota and prevention of gut microbial dysbiosis in COVID-19 patients might avoid the increased cytokine storm, which in turn might reduce the mortality rate. It has been shown that the modulation of the gut microbiota is an effective strategy to strengthen immunity and might be a possible treatment for individuals with viral infections. Currently, there is no clinical data considering the impact of the modulation of the gut microbiota on the treatment of COVID-19. We hypothesize that targeting the gut microbiota might be a novel therapeutic approach or at least a supportive therapy. In the present review article, we described the interaction between SARS-CoV-2 and gut microbiota dysbiosis through two possible mechanisms, including aberrant immune activation and aberrant mammalian target of rapamycin (mTOR) activation. Further, the disruption of the gastrointestinal reninangiotensin system (GI RAS), dysregulation of the coagulation and fibrinolytic systems, and the activity of human serine proteases in COVID-19 pathogenesis were addressed. We also provided possible strategies to restore all the discussed aspects via gut microbiota modulation.

The Influence of Prebiotics on Wheat Flour, Dough, and Bread Properties; Resistant Starch, Polydextrose, and Inulin.

The addition of prebiotics to bread is one of the most important ways to improve its techno-functional properties. In this study, the effects of resistant starch, polydextrose, and inulin on wheat flour, dough, and bread properties were investigated. The farinography results showed that resistant starch significantly increased the development time (2:18) via a boosting effect; however, polydextrose (1:48) and inulin (1:36) weakened the dough (p < 0.05). Inulin, polydextrose, and resistant starch had the greatest effect on reducing water absorption (40, 43.2, and 48.9), respectively, (p < 0.05). According to extensography data, the addition of inulin produced the best result in baking compared to other polysaccharides. In terms of baked breads, the samples containing resistant starch had high moisture content that could be due to starch gelatinization and moisture-retention, which delays the staling process of the bread. Inulin, polydextrose, and resistant starch prebiotic ingredients affected the rheological properties of the dough, overall bread quality and organoleptic characteristics; however, resistant starch was the best prebiotic used in this study.

The Oleaster (Elaeagnus angustifolia): A Comprehensive Review on Its Composition, Ethnobotanical and Prebiotic Values>.

BACKGROUND: Oleaster or Elaeagnus angustifolia is a deciduous plant from Elaegnacea family and is well-known for its remedial applications. OBJECTIVE: This paper presents a comprehensive review of the potential application of Oleaster's flour incorporated in some food products. Emphasis is given to the physicochemical, biochemical, and functional properties of Oleaster's flour. METHODS: A comprehensive search was carried out to find publications on Oleaster's flour and its application as a prebiotic. The results of the related studies were extracted and summarized in this paper. RESULTS: Oleaster's flour as a prebiotic ingredient enhances antioxidants, polyphenols, fiber, flavonoids, Sterols, carbohydrates, and protein content of food products. CONCLUSION: Further advanced investigations on Oleaster and its functional ingredients revealed that these are efficacious and can be applied as a substitute source in pharmacological industries for medical applications.

The Effects of Probiotics and Prebiotics on Mental Disorders: A Review on Depression, Anxiety, Alzheimer, and Autism Spectrum Disorders.

BACKGROUND: Probiotics and their nutrient sources (prebiotics) have been shown to have positive effects on different organs of the host. The idea of their potential benefits on Central Nervous Systems (CNS) and the incidence of Anxiety, Schizophrenia, Alzheimer, Depression, Autism, and other mental disorders has proposed a new category of medicines called "psychobiotic" which is hoped to be of low-side effect anti-inflammatory, antidepressant, and anti-anxiety constitutes. OBJECTIVE: In the current review, we present valuable insights into the complicated interactions between the GI microbiota (especially in the colon), brain, immune and central nervous systems and provide a summary of the main findings of the effects of pro- and prebiotics on important mental disorders from the potential mechanisms of action to their application in clinical practice. METHODS: Google Scholar, Pub Med, Scopus, and Science Direct databases were searched using following key words: "probiotics", "prebiotics", "mental disorders", "psychological disorders", "depression", "anxiety", "stress", "Alzheimer" and "autism spectrum". The full text of potentially eligible studies was retrieved and assessed in detail by the reviewers. Data were extracted and then summarized from the selected papers. RESULTS: The results of the provided evidence suggest that probiotic and prebiotics might improve mental function via several mechanisms. The beneficial effects of their application in Depression, Anxiety, Alzheimer and autism spectrum diseases have also been supported in clinical studies. CONCLUSION: Pro and prebiotics can improve mental health and psychological function and can be offered as new medicines for common mental disorders, however, more clinical studies are necessary to conduct regarding the clinical significance of the effects and their bioequivalence or superiority against current treatments.

Viability of microencapsulated and non-microencapsulated Lactobacilli in a commercial beverage.

The survival rate of free and encapsulated L. acidophilus and L. rhamnosus into Doogh beverage and simulated gastrointestinal conditions during 42-day were studied. Microencapsulation considerably protected both L. acidophilus and L. rhamnosus in Doogh beverage storage and in gastrointestinal conditions. Microencapsulation provided better protection to L. acidophilus than to L. rhamnosus during Doogh storage. In beverages containing the free form of bacteria, pH and acidity changes were greater than those of microencapsulated and control groups. More activity of the free probiotic bacteria (during a 42-day period especially after 21-day) produced more acid and metabolites inside the product, thereby reducing the organoleptic properties scores, However, acidity, pH and organoleptic characteristics of Doogh containing microencapsulated bacteria did not change considerably. In conclusion, this study suggests that the encapsulation and double coating of L. acidophilus and L. rhamnosus can increase the viability of them in Doogh beverage and in simulated GI conditions.

A Systematic Review and Meta-Analysis: The Effectiveness of Probiotics for Viral Gastroenteritis.

BACKGROUND: Probiotics can be used for the treatment of viral gastroenteritis. OBJECTIVE: This systematic review is to evaluate the evidence regarding the effect of probiotics on human cases of viral gastroenteritis. METHODS: The objective of this review is to evaluate the effectiveness of probiotics against placebo or standard treatment for viral gastroenteritis. A comprehensive search of Cochrane Library, EMBASE, MEDLINE via PubMed and Ovid databases, and unpublished studies (till 27 January 2018) was conducted followed by a process of study selection and critical appraisal by two independent reviewers. Randomized controlled trials assessing probiotic administration in human subjects infected with any species of gastroenteritis viruses were considered for inclusion. Only studies with a confirmed viral cause of infection were included. This study was developed using the JBI methodology for systematic reviews, which is in accordance with the PRISMA guideline. Meta-analysis was conducted where feasible. Data were pooled using the inverse variance method with random effects models and expressed as Mean Differences (MDs) with 95% Confidence Intervals (CIs). Heterogeneity was assessed by Cochran Q statistic and quantified by the I2 statistic. We included 17 RCTs, containing 3,082 patients. RESULTS: Probiotics can improve symptoms of viral gastroenteritis, including the duration of diarrhea (mean difference 0.7 days, 95% CI 0.31 to 1.09 days, n = 740, ten trials) and duration of hospitalization (mean difference 0.76 days, 95% CI 0.61 to 0.92 days, n = 329, four trials). CONCLUSION: The results of this review show that the administration of probiotics in patients with viral gastroenteritis should be considered.

New Insight for the Prognosis of CCHF: Clinical, Laboratory and Sonography Findings.

BACKGROUND: Crimean Congo Hemorrhagic Fever (CCHF) is an acute and fatal disease with various clinical and paraclinical characteristics. INTRODUCTION: In this article, we report data on confirmed CCHF cases from Iran and describe the association between studying factors and outcomes of the disease. METHODS: In the study design, we evaluated demographic characteristics, clinical, laboratory and sonographic findings of 160 CCHF confirmed cases during 2003 and 2012 in Zabol (A city in Sistan and Baluchestan province of Iran). The association between these factors and the fatal outcome were evaluated by regression analysis. RESULTS: The disease had a fatal outcome in 7 (4.4%) patients. Females had more severe symptoms and higher odds for death (odds ratio11.57, p=0.005). Leukocytosis (p<0.001), PT (p<0.001) and PTT (p=0.008) elongation, AST (p=0.010) and ALT (p>0.001) elevation were significantly associated with fatal outcome. CNS related symptoms (odds ratio 5.9, p=0.027) in clinical examination and ascites (odds ratio 38.4, p=0.012) and liquid in the pelvic cavity (odds ratio 24.2, p=0.004) were also identified as risk factors of death in this study. CONCLUSION: Our data suggest that in addition to clinical and laboratory findings practitioners consider sonography for CCHF prognosis.

Prevention of Gestational Diabetes Mellitus (GDM) and Probiotics: Mechanism of Action: A Review.

BACKGROUND: Gestational Diabetes Mellitus (GDM) is a health problem that is increasing around the world. INTRODUCTION: Prevention of GDM, rather than treatment, could have several benefits in terms of both health and economic cost. Even a slight reduction in maternal glucose in non-diabetic women, particularly in women at high risk for GDM, may have significant benefits for pregnancy results and the future health of off-springs. Probiotics are a relatively new intervention, which are assessed by mothers' metabolism, and can reduce blood sugar levels, prevent gestational diabetes and reduce the maternal and fetal complications resulting from it. The aim of this study was to review the studies on the prevention of gestational diabetes and assess the potential beneficial effects of probiotics on gestational diabetes and their possible mechanism of action. METHODS: Articles compiled through clinical trials indexed in PubMed, Science Direct, Cochran, and Medlib between 2000 and 2017, with the keywords probiotics, prevention, and gestational diabetes mellitus were selected. RESULTS: Considering the potential of probiotics in the modulation of gut microbiota, naturalization increases intestinal permeability, regulation of pro-inflammatory mediators' secretion and thereby controlling local and systemic inflammation results in decreasing intestinal permeability, enhancing the immune system. It likely has the ability to prevent or control diabetes during pregnancy although confirmatory studies are still needed. CONCLUSION: Experimental and clinical evidence support the supposition that the modulation of the gut microbiota via probiotic microorganisms could be effective in the prevention of gestational diabetes mellitus.

Survey of Salmonella infections in broiler farms in Iran during 2013-2014: a cross-sectional study.

BACKGROUND AND OBJECTIVES: The aim of this study was to determine the prevalence of Salmonella at broiler breeder farms of Iran and investigate the factors underlying salmonellosis in these farms. This is a cross-sectional investigation conducted in 23 provinces of Iran. MATERIALS AND METHODS: Fecal samples were collected from 139 broiler breeder farms in the country and standard bacteriological tests were carried out on the samples for the isolation of Salmonella. The serological tests were then applied for the samples that were positive in the bacteriological test. The information on the sampled farms extracted from the Iran GIS-VET Monitoring and Surveillance System was used for the analysis of the risk factors. RESULTS: A total of 11 farms out of the 139 sampled farms were infected with Salmonella with the largest number of infected cases related to Tehran and Fars Provinces. CONCLUSION: The statistical analysis results showed that flocks with older ages and farms with larger number of houses are at greater risk of Salmonella infection.