Optimization of anticancer exopolysaccharide production from probiotic Lactobacillus acidophilus by response surface methodology

Investigation on the exopolysaccharide production from blueberry juice fermented with lactic acid bacteria: Optimization, fermentation characteristics and Vis-NIR spectral model

The exopolysaccharide production from blueberry juice fermented were investigated. The highest exopolysaccharide yield of 2.2 ± 0.1 g/L (increase by 32.5 %) was reached under the conditions of temperature 26.5 °C, pH 5.5, inoculated quantity 5.4 %, and glucose addition 9.1 % using the artificial neural network and genetic algorithm. Under the optimal conditions, the viable cell counts and total acids were increased by 2.0 log CFU/mL and 1.6 times, respectively, while the content of phenolics and anthocyanin was decreased by 9.26 % and 7.86 %, respectively. The changes of these components affected the exopolysaccharide biosynthesis. The absorption bands of -OH and -CH associated with the main functional groups of exopolysaccharide were detected by Visible near-infrared spectroscopy. The prediction model based on spectrum results was constructed. Competitive adaptive reweighted sampling and the random forest were used to enhance the model's prediction performance with the value of RC = 0.936 and RP = 0.835, indicating a good predictability of exopolysaccharides content during fermentation.

Postbiotics as Adjuvant Therapy in Cancer Care

Postbiotics are defined as a preparation of inanimate microorganisms and/or their components that confers a health benefit to the host. They range from cell wall fragments to metabolites, bacterial lysates, extracellular vesicles, and short-chain fatty acids (SCFAs). Postbiotics may influence carcinogenesis via a variety of mechanisms. They can promote homeostatic immune responses, reduce inflammation, induce selective cytotoxicity against tumor cells, as well as the enabling the control of tumor cell proliferation and enhancing intestinal epithelial barrier function. Therefore, probiotics can serve as an adjunct strategy in anticancer treatment together with chemotherapy and immunotherapy. Up to now, the only relevant postbiotics used as interventions in oncological patients remain vitamin K molecules, with few phase-II and III trials available. In fact, postbiotics' levels are strictly dependent on the gut microbiota's composition, which may vary between individuals and can be altered under different physiological and pathological conditions. Therefore, the lack of consistent clinical evidence supporting postbiotics' efficacy is due to their poor bioavailability, short half-life, and fluctuating levels. Synbiotics, a mixture of prebiotics and probiotics, are expected to have a more homogeneous bioavailability with respect to postbiotics and may have greater potential for future development. In this review, we focus on the role of postbiotics as an adjuvant therapy in cancer treatment.

Improvement and enhancement of oligosaccharide production from Lactobacillus acidophilus using statistical experimental designs and its inhibitory effect on colon cancer

Colorectal cancer (CRC) is the third cause of death by cancers worldwide and is one of the most common cancer types reported in both Egypt and the United States. The use of probiotics as a dietary therapy is increasing either as a prevention or as a treatment for many diseases, particularly, in the case of CRC. The increasing acceptance of lactic acid bacterial (LAB) oligosaccharides as bioactive agents has led to an increase in the demand for the large-scale production of LAB-oligosaccharides using fermentation technology. Therefore, in the current study, we are using the Plackett- Burman design (PBD) approach, where sixteen experimental trials were applied to optimize the production of the target oligosaccharide LA-EPS-20079 from Lactobacillus acidophilus. Glucose, yeast extract and sodium acetate trihydrate were the top three significant variables influencing LA-EPS production. The maximum concentration of LA-EPS-20079 achieved by L. acidophilus was 526.79 μg/ml. Furthermore, Box-Behnken design (BBD) as response surface methodology (RSM) was used to complete the optimization procedure. The optimal levels of the chosen variables which were 30.0 g/l, glucose; 5 g/l, yeast extract and 10.0 g/l sodium acetate trihydrate with the predicted LA-EPS-20079 concentration of 794.82 μg/ml. Model validity reached 99.93% when the results were verified. Both optimized trials showed great cytotoxic effects against colon cancer line (CaCo-2) with inhibition percentages ranging from 64.6 to 81.9%. Moreover, downregulation in the expression level of BCL2 and Survivin genes was found with a fold change of 3.377 and 21.38, respectively. Finally, we concluded that the optimized LA-EPS-20079 has maintained its anticancer effect against the CaCo-2 cell line that was previously reported by our research group.

Probiotic-Derived Bioactive Compounds in Colorectal Cancer Treatment

Colorectal cancer (CRC) is a multifactorial disease with increased morbidity and mortality rates globally. Despite advanced chemotherapeutic approaches for the treatment of CRC, low survival rates due to the regular occurrence of drug resistance and deleterious side effects render the need for alternative anticancer agents imperative. Accumulating evidence supports that gut microbiota imbalance precedes the establishment of carcinogenesis, subsequently contributing to cancer progression and response to anticancer therapy. Manipulation of the gut microbiota composition via the administration of probiotic-derived bioactive compounds has gradually attained the interest of scientific communities as a novel therapeutic strategy for CRC. These compounds encompass miscellaneous metabolic secreted products of probiotics, including bacteriocins, short-chain fatty acids (SCFAs), lactate, exopolysaccharides (EPSs), biosurfactants, and bacterial peptides, with profound anti-inflammatory and antiproliferative properties. This review provides a classification of postbiotic types and a comprehensive summary of the current state of research on their biological role against CRC. It also describes how their intricate interaction with the gut microbiota regulates the proper function of the intestinal barrier, thus eliminating gut dysbiosis and CRC development. Finally, it discusses the future perspectives in precision-medicine approaches as well as the challenges of their synthesis and optimization of administration in clinical studies.

Optimization, fractional characterization, and antioxidant potential of exopolysaccharides from Levilactobacillus brevis NCCP 963 isolated from "kanji"

A novel exopolysaccharide (EPS) was obtained from Levilactobacillus brevis NCCP 963 isolated from a black carrot drink named "kanji". The culture conditions for maximum EPS yield were explored by the Plackett-Burman (PB) design and response surface methodology (RSM) along with the fractional characterization and antioxidant potential of EPSs. The PB design screened out five significant factors, namely, glucose, sucrose, tryptone, CaCl₂, and di-potassium phosphate out of eleven independent factors. The RSM indicated glucose and CaCl₂ as significant factors in EPS production and a maximum EPS production of 968.89 mg L^-1 was obtained at optimized levels of 10.56% glucose, 9.23% sucrose, 0.75% tryptone, 0.446% CaCl₂, and 0.385% K₂HPO₄. A R² value above 93% indicates higher variability, depicting the validity of the model. The obtained EPS has a molecular weight of 5.48 × 10⁴ Da and is a homopolysaccharide in nature with glucose monosaccharides. FT-IR analysis showed significant band stretching of C-H, O-H, C-O and C-C and indicated the β-glucan nature of EPSs. The comprehensive antioxidant investigation showed significant in vitro DPPH, ABTS, hydroxyl, and superoxide scavenging capacity with EC₅₀ values of 1.56, 0.31, 2.1, and 6.7 mg mL^-1 respectively. Curd formation from the resulting strain prevented syneresis.

Beneficial insights into postbiotics against colorectal cancer

Colorectal cancer (CRC) is one of the most prevalent and life-threatening cancer types with limited therapeutic options worldwide. Gut microbiota has been recognized as the pivotal determinant in maintaining gastrointestinal (GI) tract homeostasis, while dysbiosis of gut microbiota contributes to CRC development. Recently, the beneficial role of postbiotics, a new concept in describing microorganism derived substances, in CRC has been uncovered by various studies. However, a comprehensive characterization of the molecular identity, mechanism of action, or routes of administration of postbiotics, particularly their role in CRC, is still lacking. In this review, we outline the current state of research toward the beneficial effects of gut microbiota derived postbiotics against CRC, which will represent the key elements of future precision-medicine approaches in the development of novel therapeutic strategies targeting gut microbiota to improve treatment outcomes in CRC.

Effect of fermentation pH on the structure, rheological properties, and antioxidant activities of exopolysaccharides produced by Alteromonas australica QD

The pH value was essential for the growth and metabolism of microorganisms. Acidic pH exopolysaccharide (AC-EPS) and alkaline pH exopolysaccharide (AL-EPS) secreted by A. australica QD mediated by pH were studied in this paper. The total carbohydrate content and molecular weight of AC-EPS (79.59% ± 2.24% (w/w), 8.374 × 10⁵ Da) and AL-EPS (82.48% ± 1.46% (w/w), 6.182 × 10⁵ Da) were estimated and compared. In AC-EPS, mannose (3.78%) and galactose (3.24%) content was more, while the proportion of glucuronic acid was less in comparison to AL-EPS. The scanning electron microscopy revealed the structural differences among the AC-EPS and AL-EPS. Thermogravimetric analysis showed degradation temperatures of 272.8 °C and 244.9 °C for AC-EPS and AL-EPS, respectively. AC-EPS was found to exhibit better rheological properties and emulsifying capabilities, while AL-EPS had superior antioxidant activities. Overall, both AC-EPS and AL-EPS have the potential to be used as emulsifiers and biological antioxidants.

Lactic Acid Bacteria as Mucosal Immunity Enhancers and Antivirals through Oral Delivery

Mucosal vaccination offer an advantage over systemic inoculation from the immunological viewpoint. The development of an efficient vaccine is now a priority for emerging diseases such as COVID-19, that was declared a pandemic in 2020 and caused millions of deaths globally. Lactic acid bacteria (LAB) especially Lactobacillus are the vital microbiota of the gut, which is observed as having valuable effects on animals’ and human health. LAB produce lactic acid as the major by-product of carbohydrate degradation and play a significant role in innate immunity enhancement. LAB have significant characteristics to mimic pathogen infections and intrinsically possess adjuvant properties to enhance mucosal immunity. Increasing demand and deliberations are being substantially focused on probiotic organisms that can enhance mucosal immunity against viral diseases. LAB can also strengthen their host’s antiviral defense system by producing antiviral peptides, and releasing metabolites that prevent viral infections and adhesion to mucosal surfaces. From the perspectives of “one health” and the use of probiotics, conventional belief has opened up a new horizon on the use of LAB as antivirals. The major interest of this review is to depict the beneficial use of LAB as antivirals and mucosal immunity enhancers against viral diseases.

Artificial neural network modeling and statistical optimization of medium components to enhance production of exopolysaccharide by Bacillus sp. EPS003

Microbial Exopolysaccharides (EPS) have a wide range of applications in food, cosmetics, agriculture, pharmaceutical industries, and environmental bioremediation. The present study aims at enhancing the production of EPS from a soil-isolate Bacillus sp. EPS003. Effects of carbon and nitrogen sources and process conditions were evaluated one factor at a time. Box-Behnken design has been used and a 2.5-fold increase in yield is reported after optimizing the most influential parameters sucrose, yeast extract, and peptone as identified by the Plackett-Burman method. An artificial neural network (ANN) with two different topologies (EPS-NN1 and EPS-NN2) was developed. On comparing prediction accuracy, EPS-NN2 formulated as one input layer with four input variables (sucrose, yeast extract, peptone, biomass), a single hidden layer with seven neurons and EPS yield in the output layer showed a high coefficient of determination (R²-0.98) and low error (NRMSE-0.024). This study concludes that the consideration of biomass value has increased the prediction accuracy of the model.

Exopolysaccharides Produced by Lactic Acid Bacteria: From Biosynthesis to Health-Promoting Properties

The production of exopolysaccharides (EPS) by lactic acid bacteria (LAB) has attracted particular interest in the food industry. EPS can be considered as natural biothickeners as they are produced in situ by LAB and improve the rheological properties of fermented foods. Moreover, much research has been conducted on the beneficial effects of EPS produced by LAB on modulating the gut microbiome and promoting health. The EPS, which varies widely in composition and structure, may have diverse health effects, such as glycemic control, calcium and magnesium absorption, cholesterol-lowering, anticarcinogenic, immunomodulatory, and antioxidant effects. In this article, the latest advances on structure, biosynthesis, and physicochemical properties of LAB-derived EPS are described in detail. This is followed by a summary of up-to-date methods used to detect, characterize and elucidate the structure of EPS produced by LAB. In addition, current strategies on the use of LAB-produced EPS in food products have been discussed, focusing on beneficial applications in dairy products, gluten-free bakery products, and low-fat meat products, as they positively influence the consistency, stability, and quality of the final product. Highlighting is also placed on reports of health-promoting effects, with particular emphasis on prebiotic, immunomodulatory, antioxidant, cholesterol-lowering, anti-biofilm, antimicrobial, anticancer, and drug-delivery activities.

Optimization of food-grade medium for co-production of bioactive substances by Lactobacillus acidophilus LA-5 for explaining pharmabiotic mechanisms of probiotic

This study aimed to optimize the co-production of conjugated linoleic acid (CLA), exopolysaccharides (EPSs) and bacteriocins (BACs) by Lactobacillus acidophilus LA-5 in dairy food-grade by-product. The factorial design revealed that the significant factors were temperature, time, and yeast extract. Then the response surface methodology was used for optimization. At the optimal conditions the viable cell number, CLA, EPSs, and inhibition activity were 2.62 ± 0.49 × 108 CFU/mL, 51.46 ± 1.50 μg/mL, 348.24 ± 5.61 mg/mL and 12.46 ± 0.80 mm, respectively. FTIR, GC, TLC, and SDS page analysis revealed the functional groups of pharmabiotics. The FTIR, GC, TLC, and SDS page analysis showed that both CLA isomers (c-9, t-11, and t-10, c-12) produced. The FTIR, GC, TLC, and SDS page analysis indicated that produced EPSs were composed of glucose, mannose, galactose, xylose, and fructose. FTIR, GC, TLC, and SDS page used to report BACs molecular weight, which showed two fractions by molecular mass 35 and 63 kDa. Previously the ability of different probiotic bacteria investigated and optimized the production of CLA, EPSs, and BACs, but, there was no report on the co-producing capacity of these bioactive metabolites by probiotics. The present work was investigated to optimize the co-production of pharmabiotic metabolites by L. acidophilus LA-5, in supplemented cheese whey as a cultivation medium.

Gastrointestinal transit tolerance, cell surface hydrophobicity, and functional attributes of Lactobacillus Acidophilus strains isolated from Indigenous Dahi

Strains of Lactobacillus acidophilus WFA1 (KU877440), WFA2 (KU877441), and WFA3 (KU877442) were isolated from indigenous Dahi (yogurt), screened, and selected based on acid and bile tolerance along with the antimicrobial activity. These selected strains were further assessed for their probiotic and functional attributes. Results for simulated gastric and intestinal tolerance/ resistance revealed that all three strains can resist and survive under the following mentioned conditions. To access cell surface hydrophobicity, bacterial adhesion to hydrocarbons (BATH), cellular auto-aggregation, and salt aggregation were performed. In BATH, adhesion of strains against three hydrocarbons namely xylene, dichloromethane, and hexadecane was conducted. The results show that strains showed the least adhesion to xylene (54.25%) as compared to dichloromethane (55.25%) and hexadecane (56.65%). WFA1 showed maximum adherence percentage (55.48%) followed WFA2 (55.48%) and WFA3 (51.38%). Cellular auto-aggregation varied from 21.72% to 30.73% for WFA3 and WFA1, respectively. In the salt aggregation test (SAT), WFA1, WFA2, and WFA3 aggregated at 0.6, 1.0, and 2.0 molar concentrations of ammonium sulfate, respectively. PCR amplification of bile salt hydrolase gene (bsh) was performed and sequences were submitted to the public database of NCBI and Gene bank under accession numbers, KY689139, KY689140, and KY689141. Additionally, a cholesterol-lowering assay was conducted and up to 26% reduction in cholesterol was observed by the strains. Regarding functional properties, exopolysaccharide (EPS) production, and antioxidant potential, strain WFA1 showed promising results EPS (1.027mg/ml), DPPH (80.66%), ABTS (81.97%), and reducing power (1.787). It can be concluded from the present study that the mentioned strains of L. acidophilus (WFA1, WFA2, and WFA3) are strongly hydrophobic; thus having an ability to survive and colonize under the gastrointestinal tract which confirms their probiotic nature. Regarding their functional properties, L. acidophilus WFA1 (KU877440) showed excellent properties of antioxidants and EPS production.

Challenges in the production and use of probiotics as therapeuticals in cancer treatment or prevention

Probiotics were defined as microbial strains that confer health benefits to their consumers. The concept has evolved during the last twenty years, and today metabolites produced by the strains, known as postbiotics, and even dead cells, known as paraprobiotics are closely associated to them. The isolation of commensal strains from human microbiome has led to the development of next generation probiotics. This review aims to present an overview of the developments in the area of cancer prevention and treatment, intimately related to advances in the knowledge of the microbiome role in its genesis and therapy. Strain identification and characterization, production processes, delivery strategies and clinical evaluation are crucial to translate results into the market with solid scientific support. Examples of recent tools in isolation, strain typification, quality control and development of new probiotic strains are described. Probiotics market and regulation were originally developed in the food sector, but these new strategies will impact the pharmaceutical and health sectors, requiring new considerations in regulatory frameworks.

Exopolysaccharides from Lactobacillus acidophilus modulates the antioxidant status of 1,2-dimethyl hydrazine-induced colon cancer rat model

The aim of the current study is to ascertain the anticancer activity of exopolysaccharides (EPS) from probiotic Lactobacillus acidophilus in the 1, 2-dimethyl hydrazine (DMH)-induced colon cancer rat model and to determine the antioxidant status. Rats were divided into five groups of six animals each. Group I served as control, group II served as cancer control (DMH alone administered), group III as standard drug control (5-FU along with DMH) and group IV and V received EPS in two doses (200 mg/kg body weight and 400 mg/kg body weight along with DMH). EPS administration was found to reduce the number of polyps formed (Group IV-8.25 ± 1.258 and Group V-8.50 ± 1.732 vs Group II-14.50 ± 2.380) and to increase the levels of antioxidant enzymes viz. Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and antioxidants like vitamin C (Vit. C), reduced glutathione (GSH) which was found to be reduced in colon cancer control rats. The status of lipid peroxidation (LPO) was also evaluated. All the values which were affected by the supplementation of DMH were brought to near normal levels by the treatment with EPS. The well-preserved histology of colon and the biochemical evaluation also show that EPS could be a potential agent for the prevention and treatment of colon cancer.

The anti-cancer effects and mechanisms of lactic acid bacteria exopolysaccharides in vitro: A review

Probiotic lactic acid bacteria (LAB) are a particular group of gram-positive bacteria that are usually involved in natural ferments and widely used in food manufacture industry. Most of them can produce exopolysaccharides (EPS), surface carbohydrate polymers with diverse biological functions. LAB EPS are potentially complementary and alternative medicines against cancer. EPS show anti-proliferative effects on a variety of tumor cells from intestine, liver, breast, etc. They modulate the development of tumors through various mechanisms including promoting apoptosis, inducing cell cycle arrest as well as anti-mutagenic, anti-oxidative, anti-angiogenesis and anti-inflammatory effects. Bacterial origin, existence form, chemical structure, purity et al. are important factors affecting the anticancer effects of EPS. The future challenge lies in elucidating the precise structure-function relationship of LAB EPS. Besides, more in vivo studies and further clinical trials are indispensable to confirm the anticancer effects.

Application of microbial extracellular carbohydrate polymeric substances in food and allied industries

Extracellular polymeric substances (EPS) are biopolymers, composed of polysaccharides, nucleic acids, proteins and lipids, which possess unique functional properties. Despite significant strides made in chemical production processes for polymers, the niche occupied by exopolysaccharides produced by bacteria, yeast or algae is steadily growing in its importance. With the availability of modern tools, a lot of information has been generated on the physico-chemical and biological properties using spectrometric tools, while advanced microscopic techniques have provided valuable insights into the structural-functional aspects. The size of EPS generally ranges between 10 and 10,000 kDa. The wide spectra of applications of EPS as adhesives, stabilizer, gelling, suspending, thickening agent, and surfactants in food and pharmaceutical industries are observed. The health benefits of these EPS enable the improvement of dual function, added value, and green products. This review summarizes previous work on the structural composition, rheological and thermal behaviour, and biosynthetic pathways of EPS and bioprocesses developed for their production. This review also considers each of the above factors and presents the current knowledge on the importance and refinement of available downstream protocols and genetic engineering towards specific food applications, which can help to diversify their prospects in different food and allied industries.

The Effects of Probiotic Supplementation on Clinical Symptom, Weight Loss, Glycemic Control, Lipid and Hormonal Profiles, Biomarkers of Inflammation, and Oxidative Stress in Women with Polycystic Ovary Syndrome: a Systematic Review and Meta-analysis of Randomized Controlled Trials

The purpose of this systematic review and meta-analysis of randomized controlled trials (RCTs) is to determine the effectiveness of probiotic supplementation on clinical symptoms, weight loss, glycemic control, lipid and hormonal profiles, and biomarkers of inflammation and oxidative stress in women with polycystic ovary syndrome (PCOS). Eligible studies were systematically searched from Cochrane Library, Embase, Medline, and Web of Science databases until January 2019. Cochran (Q) and I-square statistics were used to measure heterogeneity among included studies. Data were pooled by using random-effect model and expressed as standardized mean difference (SMD) with 95% confidence interval (CI). Eleven articles were included in this meta-analysis. Probiotic supplementation significantly decreased weight (SMD - 0.30; 95% CI, - 0.53, - 0.07; P = 0.01), body mass index (BMI) (SMD - 0.29; 95% CI, - 0.54, - 0.03; P = 0.02), fasting plasma glucose (FPG) (SMD - 0.26; 95% CI, - 0.45, - 0.07; P < 0.001), insulin (SMD - 0.52; 95% CI, - 0.81, - 0.24; P < 0.001), homeostatic model assessment for insulin resistance (HOMA-IR) (SMD - 0.53; 95% CI, - 0.79, - 0.26; P < 0.001), triglycerides (SMD - 0.69; 95% CI, - 0.99, - 0.39; P < 0.001), VLDL-cholesterol (SMD - 0.69; 95% CI, - 0.99, - 0.39; P < 0.001), C-reactive protein (CRP) (SMD - 1.26; 95% CI, - 2.14, - 0.37; P < 0.001), malondialdehyde (MDA) (SMD - 0.90; 95% CI, - 1.16, - 0.63; P < 0.001), hirsutism (SMD - 0.58; 95% CI, - 1.01, - 0.16; P < 0.001), and total testosterone levels (SMD - 0.58; 95% CI, - 0.82, - 0.34; P < 0.001), and also increased the quantitative insulin sensitivity check index (QUICKI) (SMD 0.41; 95% CI, 0.11, 0.70; P < 0.01), nitric oxide (NO) (SMD 0.33; 95% CI 0.08, 0.59; P = 0.01), total antioxidant capacity (TAC) (SMD 0.64; 95% CI, 0.38, 0.90; P < 0.001), glutathione (GSH) (SMD 0.26; 95% CI, 0.01, 0.52; P = 0.04), and sex hormone binding globulin (SHBG) levels (SMD 0.46; 95% CI, 0.08, 0.85; P = 0.01). Probiotic supplementation may result in an improvement in weight, BMI, FPG, insulin, HOMA-IR, triglycerides, VLDL-cholesterol, CRP, MDA, hirsutism, total testosterone, QUICKI, NO, TAC, GSH, and SHBG but did not affect dehydroepiandrosterone sulfate levels, and total, LDL, and HDL cholesterol levels in patients with PCOS.

The effects of synbiotic supplementation on markers of insulin metabolism and lipid profiles in gestational diabetes: a randomised, double-blind, placebo-controlled trial

To the best of our knowledge, data on the effects of synbiotic supplementation on markers of insulin metabolism and lipid concentrations in patients with gestational diabetes mellitus (GDM) are scarce. The aim of the current study was to determine the effects of synbiotic supplementation on markers of insulin metabolism and lipid profiles in GDM patients. In total, seventy patients with GDM aged 18-40 years were assigned to two groups - the synbiotic group (n 35) and the placebo group (n 35) - in this randomised, double-blind, placebo-controlled trial. Patients in the synbiotic group received a daily capsule that contained three viable and freeze-dried strains: Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium bifidum (2×109 colony-forming units/g each) plus 800 mg inulin for 6 weeks. Fasting blood samples were collected at the beginning and week 6 to quantify related markers. After 6 weeks of intervention, compared with the placebo, synbiotic supplementation led to a significant decrease in serum insulin levels (-1·5 (sd 5·9) v. +4·8 (sd 11·5) µIU/ml, P=0·005), homoeostatic model assessment for insulin resistance (-0·4 (sd 1·3) v. +1·1 (sd 2·7), P=0·003) and homoeostatic model assessment for β cell function (-5·1 (sd 24·2) v. +18·9 (sd 45·6), P=0·008) and a significant increase in quantitative insulin sensitivity check index (+0·01 (sd 0·01) v. -0·007 (sd 0·02), P=0·02). In addition, synbiotic intake significantly decreased serum TAG (-14·8 (sd 56·5) v. +30·4 (sd 37·8) mg/dl, P<0·001) and VLDL-cholesterol concentrations (-3·0 (sd 11·3) v. +6·1 (sd 7·6) mg/dl, P<0·001) compared with the placebo. Overall, the results of this study demonstrate that taking synbiotic supplements for 6 weeks among patients with GDM had beneficial effects on markers of insulin metabolism, TAG and VLDL-cholesterol concentrations.