Fructooligosaccharides Research Articles

Engineering a heterologously expressed fructosyltransferase from Aspergillus oryzae N74 in Komagataella phaffii (Pichia pastoris) for kestose production

Fructo-oligosaccharides (FOS) are one of the most well-studied and commercialized prebiotics. FOS can be obtained either by controlled hydrolysis of inulin or by sucrose transfructosylation. FOS produced from sucrose are typically classified as short-chain FOS (scFOS), of which the best known are 1-kestotriose (GF2), 1,1-kestotetraose (GF3), and 1,1,1-kestopentaose (GF4), produced by fructosyltransferases (FTases) or β-fructofuranosidases. In previous work, FOS production was studied using the Aspergillus oryzae N74 strain, its ftase gene was heterologously expressed in Komagataella phaffii (Pichia pastoris), and the enzyme’s tertiary structure modeled. More recently, residues that may be involved in protein–substrate interactions were predicted. In this study, the aim was to experimentally validate previous in silico results by independently producing recombinant wild-type A. oryzae N74 FTase and three single-point mutations in Komagataella phaffii (Pichia pastoris). The R163A mutation virtually abolished the transfructosylating activity, indicating a requirement for the positively charged arginine residue in the catalytic domain D. In contrast, transfructosylating activity was improved by introducing the mutations V242E or F254H, with V242E resulting in higher production of GF2 without affecting that of GF3. Interestingly, initial sucrose concentration, reaction temperature and the presence of metal cofactors did not affect the enhanced activity of mutant V242E. Overall, these results shed light on the mechanism of transfructosylation of the FTase from A. oryzae and expand considerations regarding the design of biotechnological processes for specific FOS production.

Viability of probiotics, physicochemical and microbiological characterization of beverage (smoothie) with symbiotic yogurt and berries pulp

The aim of this study was to evaluate the viability of commercial probiotic bacteria (bifidobacteria) in symbiotic beverages made with symbiotic yoghurts and berries pulp, after manufacturing and refrigerated storage. Six beverage formulations were prepared using symbiotic yogurt (60%) containing inulin or fructooligosaccharides (FOS) and commercial probiotic cultures (Bifidobacterium spp.) and berries pulp (40%), as follows: F1 (Howaru HN 019, inulin); F2 (Howaru HN 019, FOS); F3 (Lafti B 94, inulin); F4 (Lafti B 94, FOS); F5 (Kit Bifi, inulin); F6 (Kit Bifi, FOS). The beverages were evaluated for microbiological quality (total and thermotolerant coliforms, molds and yeasts), viability of probiotics, pH and titratable acidity. The pH, acidity and probiotic counts were investigated during 30 days of storage. The physicochemical characterization of the formulations with better performance regarding the maintenance of probiotic counts was carried out. The beverages elaborated showed appropriate sanitary hygienic quality, decreased pH and increased acidity, which is common in fermented dairy products. The probiotic Howaru HN019 exhibited better stability in the beverage than Lafti B4 and Kit Bifi. The highest level of bifidobacteria was found in F1 and F2 beverages containing B. animalis (Howaru HN019) and inulin or FOS, remained around 8 log CFU.mL-1 for up to 30 days, whereas levels of 6 to 7 log CFU.mL-1 were maintained in the other beverages. The beverages made with symbiotic yogurt and berries pulp can be considered an appropriate vehicle for the incorporation of probiotics and fibers, whereas, the probiotics remain at a satisfactory level throughout storage.

From sucrose to fructo-oligosaccharides: Production and purification of fructo-oligosaccharides by an integrated enzymatic catalysis and membrane separation process

Fructo-oligosaccharides (FOS) are a group of linear fructose oligomers with numerous health benefits, which can be synthesized by the transfructosylation of sucrose using fructosyltransferases (FTases). In this study, it was found that the selected FTases showed both hydrolytic and transfructosylating activities. For FOS production, the hydrolytic activities of FTases became significant when the reaction time was above 1 h. Thus, FTases needed to be inactivated or removed from the reactor after achieving the highest FOS conversion. We therefore developed an integrated ultrafiltration-diafiltration- concentration process for FTases reuse and FOS purification. Because of the 100% rejection of FTases activity and a higher average flux, a PES-10 ultrafiltration membrane was selected for FTases recovery, where the cake layer formation was the main membrane fouling mechanism. Then, a fed-batch reaction process was developed for FOS production, where the hydrolytic behavior of FTases was negligible, and the FTases dosage was reduced by 75% compared to single batch operation (four batches). Moreover, the FOS production was comparable, and 95.5% FTases was recovered by the PES10 membrane after the four fed-batches processes. Subsequently, a NF5 nanofiltration membrane was selected to further separate FOS from the FTases-free FOS solution by a constant volume diafiltration process under 45 °C, and the monosaccharides in the reaction mixture (glucose and fructose) were completely removed, increasing the FOS purity from 55.8% to 92.3%. Finally, the FOS and sucrose in the diafiltration permeate was recovered by a DL nanofiltration membrane under 60 °C. The outcome of this work offers a complete technical route for FOS production using sucrose as substrate.

Effect of prebiotics on Bacteroides sp. adhesion and biofilm formation and synbiotic effect on Clostridioides difficile.

Aim: The objective of this study was to determine the effect of standard and candidate prebiotics on the adhesion and biofilm formation of Bacteroides sp. in monoculture and co-culture with Clostridioides difficile. Materials & methods: The effect of seven prebiotics on the adhesion and biofilm formation of Bacteroides sp. to three human cell lines was determined. The effect of Bacteroides sp. and fructooligosaccharides (FOS) on the adhesion and biofilm formation of C. difficile was tested by the co-incubation assay. Results: Inulin, mannose and raffinose presented the best anti-adhesion properties against Bacteroides sp. Combination of Bacteroides sp. with FOS decreased theadhesion of C. difficile. Conclusion: The study shows the potential role of prebiotics and synbiotics in decreasing the burden of C. difficile infections.

Oligosaccharides Ameliorate Acute Kidney Injury by Alleviating Cluster of Differentiation 44-Mediated Immune Responses in Renal Tubular Cells.

Acute kidney injury (AKI) is a sudden episode of kidney damage that commonly occurs in patients admitted to hospitals. To date, no ideal treatment has been developed to reduce AKI severity. Oligo-fucoidan (FC) interferes with renal tubular cell surface protein cluster of differentiation 44 (CD44) to prevent renal interstitial fibrosis; however, the influence of oligosaccharides on AKI remains unknown. In this study, FC, galacto-oligosaccharide (GOS), and fructo-oligosaccharide (FOS) were selected to investigate the influence of oligosaccharides on AKI. All three oligosaccharides have been proven to be partially absorbed by the intestine. We found that the oligosaccharides dose-dependently reduced CD44 antigenicity and suppressed the hypoxia-induced expression of CD44, phospho-JNK, MCP-1, IL-1β, and TNF-α in NRK-52E renal tubular cells. Meanwhile, CD44 siRNA transfection and JNK inhibitor SP600125 reduced the hypoxia-induced expression of phospho-JNK and cytokines. The ligand of CD44, hyaluronan, counteracted the influence of oligosaccharides on CD44 and phospho-JNK. At 2 days post-surgery for ischemia–reperfusion injury, oligosaccharides reduced kidney inflammation, serum creatine, MCP-1, IL-1β, and TNF-α in AKI mice. At 7 days post-surgery, kidney recovery was promoted. These results indicate that FC, GOS, and FOS inhibit the hypoxia-induced CD44/JNK cascade and cytokines in renal tubular cells, thereby ameliorating AKI and kidney inflammation in AKI mice. Therefore, oligosaccharide supplementation is a potential healthcare strategy for patients with AKI.

Influence of codon optimization, promoter, and strain selection on the heterologous production of a β-fructofuranosidase from Aspergillus fijiensis ATCC 20611 in Pichia pastoris.

Fructooligosaccharides (FOS) are compounds possessing various health properties and are added to functional foods as prebiotics. The commercial production of FOS is done through the enzymatic transfructolysation of sucrose by β-fructofuranosidases which is found in various organisms of which Aureobasidium pullulans and Aspergillus niger are the most well known. This study overexpressed two differently codon-optimized variations of the Aspergillus fijiensis β-fructofuranosidase-encoding gene (fopA) under the transcriptional control of either the alcohol oxidase (AOX1) or glyceraldehyde-3-phosphate dehydrogenase (GAP) promoters. When cultivated in shake flasks, the two codon-optimized variants displayed similar volumetric enzyme activities when expressed under control of the same promoter with the GAP strains producing 11.7 U/ml and 12.7 U/ml, respectively, and the AOX1 strains 95.8 U/ml and 98.6 U/ml, respectively. However, the highest production levels were achieved for both codon-optimized genes when expressed under control of the AOX1 promoter. The AOX1 promoter was superior to the GAP promoter inbioreactor cultivationsfor both codon-optimized genes with 13,702 U/ml and 2718 U/ml for the AOX1 promoter for ATUM and GeneArt®, respectively, and 6057 U/ml and 1790 U/ml for the GAP promoter for ATUM and GeneArt®, respectively. The ATUM-optimized gene produced higher enzyme activities when compared to the one from GeneArt®, under the control of both promoters.

Potential prebiotic effects of nonabsorptive components of Keemun and Dianhong black tea: an in vitro study

Black tea is a healthy and popular tea beverage. However, its main bioactive compounds (theaflavins and thearubigins) are not easily absorbed. The aim of this study was to investigate the modulation of intestinal microbiota by the nonabsorptive components of Keemun black tea (KBT) and Dianhong black tea (DBT), and fructooligosaccharide (FOS) was selected for use in the control group. KBT, DBT, and FOS significantly increased total short-chain acid production. Specifically, FOS treatment predominantly increased the production of acetic acids and black tea treatments increased the production of acetic, propionic, and butyric acids at similar rates. Moreover, FOS exerted a strong bifidogenic effect after 24 h of fermentation; KBT and DBT increased the abundance of the beneficial genus Bacteroides and Roseburia. In summary, the nonabsorptive components of KBT and DBT could serve as novel prebiotics, the underlying mechanisms of which are quite different from those of FOS.

Development of new strategies for the production of high-purity fructooligosaccharides using β-fructofuranosidase and a novel isolated Wickerhamomycesanomalus

• A novel W. anomalus used for purifying G-type FOS syrup was isolated. • Three new strategies for P-type FOS syrup production were developed. • The P-type FOS syrup with high purity of 95.6 ± 1.5% (w/w) was obtained. • High yield of 0.63 g FOS /g sucrose and productivity of 3.44 g FOS /L·h was achieved. • This study provided a feasible strategy for P-type FOS syrup production. Fructooligosaccharides (FOS), as an internationally recognized prebiotics, are in widespread used in the food industry. However, the purity of FOS syrup produced by enzyme conversion or microbial fermentation is usually only 55% (w/w, called G-type FOS syrup), which limits its application to health food. Thus, the means of improving the purity of G-type FOS syrup to prepare high-purity (greater than 95%, w/w) FOS syrup (i.e., P-type FOS) has long been a topic of concern. In this study, GXL-22, a novel yeast, was isolated and identified as Wickerhamomyces anomalus for use in purifying G-type FOS syrup by removing fructose, glucose, and sucrose. The purity of the G-type FOS syrup was increased to 87.2 ± 1.3% (w/w) after optimization of the process parameters. Three new strategies for the production of P-type FOS syrup from G-type FOS syrup or sucrose were developed from the transglycosidation and hydrolysis activity of β-fructofuranosidase and the fermentation characteristic of the yeast. A maximum FOS purity of 95.6 ± 1.5% (w/w) with yield of 0.63 ± 0.02 g FOS /g sucrose and productivity of 3.44 ± 0.08 g FOS /L·h was obtained through the successive action of β-fructofuranosidase transglycosidation and yeast fermentation in a 10 L fermenter using 300 g/L sucrose as a substrate, which provided a feasible strategy for the industrial production of P-type FOS syrup.

Impact of dietary fructooligosaccharides (FOS) on murine gut microbiota and intestinal IgA secretion.

The online version contains supplementary material available at 10.1007/s13205-022-03116-3.

Convective drying of yacón (Smallanthus sonchifolius) slices: A simple physical model including shrinkage

Yacón is a tuberous root from the Andean region, and a functional food due to the presence of fructo-oligosaccharides (FOS). Due to its high moisture in natura, the product is prone to microbial degradation. The evolution of yacón cylindrical slices under convective drying is here studied from experimental work and theoretical considerations about bulk properties. The operation of a pilot-scale convective dryer allowed monitoring the moisture and dimensions of yacón slices. Evolution of moisture under controlled temperature and relative humidity conditions is described through a two-parameter drying kinetics model. A novel approach for estimating shrinkage effects is proposed, comparing measured dimensions with predictions based upon hypothetical shrinkage behaviors. The drying kinetics and the shrinkage approach are finally combined with the global energy balance for a single slice, in order to describe the evolution of surface temperature and other yacón slice properties along the drying period.

Penatalaksanaan Kadar Gula Darah Tikus Putih (Rattus norvegicus) Model Diabetes Mellitus Tipe 2 Menggunakan Rebusan Umbi Yakon (Smallanthus sonchifolius)

The world health organization recommends the use of traditional medicines for chronic and degenerative diseases in maintaining health and helping to improve their safety and efficacy. The Yakon (SS) tubers contain FOS (Fructooligosaccharides) as a lowering of blood sugar levels. The purpose of this study was to determine blood sugar levels after treatment with boiled Yakon tubers (SS). This type of research is an experimental design with a pre-post test with a control-group design. The independent variable is the boiled water of Yakon tubers, the dependent variable is blood sugar levels. The samples were divided into 2 groups: the treatment group of boiled Yakon tuber (Smallanthus s) dose 1 (350 mg/kg/BW) and dose 2 (700 mg/kg/BW), the control group. Each group consisted of 6 rats. Mice were conditioned to hyperglycemia by being given a high-glucose diet for 9 weeks. Blood sugar measurement using Gluco-D, data analysis used is Paired Sample T-Test, Independent, Sample T-Test, and One Way Anova. The results showed that treatment dose 1 experienced an average decrease in blood sugar levels by 158.5 mg/dl (p 0.004) and dose 2 by 161.17 mg/dl (p 0.001). The results of the study were the control group and treatment 1 (Sig.2-tailed) = .000 (0.05) and the control group with treatment 2 (Sig.2-tailed) = .000 (0.05) While the comparison results showed that there was a difference between the control group with treatment group 1, and control group with treatment 2 respectively (Sig.2-tailed)=0.000, =0.05. The results of this study indicate that there is an effect of boiled water from Yakon tubers. The Yakon tuber boiled water can be implemented as an alternative in the management of blood sugar in conditions of diabetes mellitus.

Fructooligosaccharide Reduces Weanling Pig Diarrhea in Conjunction with Improving Intestinal Antioxidase Activity and Tight Junction Protein Expression.

This study was to illustrate the effects of fructooligosaccharide (FOS) on the antioxidant capacity, intestinal barrier function, and microbial community of weanling pigs. Results showed that FOS reduced the incidence of diarrhea (6.5 vs. 10.8%) of pigs (p < 0.05) but did not affect growth performance when compared with the control group. A diet supplemented with FOS increased ileal mRNA expression of occludin (1.7 vs. 1.0), claudin-1 (1.9 vs. 1.0), claudin-2 (1.8 vs. 1.0), and claudin-4 (1.7 vs. 1.0), as well as colonic mRNA expression of ZO-1 (1.6 vs. 1.0), claudin-1 (1.7 vs. 1.0), occludin (1.9 vs. 1.0), and pBD-1 (1.5 vs. 1.0) when compared with the control group (p < 0.05). FOS supplementation improved the anti-oxidase activity and expression of nuclear factor erythroid-2 related factor 2 (Nrf2), and decreased concentrations of D-lactate (3.05 U/L vs. 2.83 U/L) and TNF-α (59.1 pg/mL vs. 48.0 pg/mL) in the serum when compared with the control group (p < 0.05). In addition, FOS increased Sharpea, Megasphaera, and Bacillus populations in the gut when compared with the control group (p < 0.05). Association analysis indicated that mRNA expression of occludin and claudin-1 in the ileal mucosa were correlated positively with populations of Sharpea and Bacillus (p < 0.05). Furthermore, mRNA expression of occludin and claudin-1 in the colonic mucosa were correlated positively with abundances of Sharpea, Lactobocillus, and Bifidobacterium (p < 0.05). In conclusion, FOS activated Nrf2 signaling and increased the expression of specific tight junction proteins, which were associated with reduced diarrhea incidence.

Consumption of caffeinated and decaffeinated coffee enriched with cocoa and fructo-oligosaccharides among non-diabetic persons: Double blind randomized clinical trial.

Food industry has been investing in bringing to the market coffee-based drinks enriched in compounds that promise weight loss, which consequently influences diabetes risk. However, there are no clinical trials showing the effects of brewed coffee (with or without caffeine) enriched with bioactive compounds on body fat and glycemic control in healthy individuals. Therefore, we have evaluated the effect of consuming two coffee formulas enriched with cocoa and fructo-oligosaccharides (FOS) on glycemic and anthropometric biomarkers and blood pressure in non-diabetic adults for 10weeks. In general, we observed that the values of fasting plasma glucose (FPG) (p=.006) and fasting capillary blood glucose (FCBG) (p<.001) had lower values with a tendency to decrease in FCG (p=.003) and FBG (p<.005) in both formulas. We observed statistically significant reductions in waist circumference (WC) (p=.012), arm circumference (AC) (p=.015), and percentage of fat (<0.0001) for all participants. However, we noticed a greater reduction in the caffeinated formula group (-2.92%, p=.005) compared to the decaffeinated formula (-1.62%, p=.008). Consumers of both cocoa and FOS-enriched coffee formulas benefited from reduced FBG, FCG, WC, and body fat percentage. The consumption of caffeinated formula was more effective in reducing the percentage of fat, while the decaffeinated formula was more effective in reducing diastolic blood pressure. PRACTICAL APPLICATIONS: This study provides robust evidence that effects of fortified coffee on non-diabetic people is positive for reduction in blood glucose, body fat and diastolic blood pressure. This study proposes a practical and safe coffee formulation for the consumption of caffeinated and decaffeinated coffee for non-diabetic people.

Growth and survival of Bifidobacterium breve and Bifidobacterium longum in various sugar systems with fructooligosaccharide supplementation

This study aims to investigate the effect of fructooligosaccharide (FOS) (0.5, 1, 2, 3, and 4%) supplementation on the growth and survival of Bifidobacterium breve and Bifidobacterium longum in glucose, fructose, lactose, and sucrose (2, 3, and 4%) systems with 24-h growth and 10-day survival assays at 37 °C. FOS supplementation showed a higher growth-promoting effect on B. longum than B. breve in various sugar systems. The highest percentage of increase in growth index, 78.5%, was observed with 4% sucrose supplemented with 0.5% FOS in B. longum. In comparison, the highest percentage increase in growth index, 5.6 and 6.6%, was observed in the presence of 2% glucose and 4% lactose supplemented with 0.5% FOS in B. breve. In survival assay, FOS supplementation (0.5–4%) in a 2% lactose system showed the highest positive effect on the cell viability of B. longum on day-10. As for B. breve, FOS supplementation (1 and 2%) in the 2% sucrose system showed the highest positive effect on the cell viability, followed by FOS supplementation (0.5, 3, and 4%) in 2% sucrose and FOS supplementation (3 and 4%) in 2% lactose on day-10. This study demonstrated that the efficacy of FOS supplementation was depended on its concentration, sugar system and its concentration, and Bifidobacterium strain.

Lactiplantibacillus plantarum subsp. plantarum and Fructooligosaccharides Combination Inhibits the Growth, Adhesion, Invasion, and Virulence of Listeria monocytogenes.

Listeria monocytogenes is a foodborne pathogen responsible for many food outbreaks worldwide. This study aimed to investigate the single and combined effect of fructooligosaccharides (FOS) and Lactiplantibacillus plantarum subsp. plantarum CICC 6257 (L. plantarum) on the growth, adhesion, invasion, and virulence of gene expressions of Listeria monocytogenes 19112 serotype 4b (L. monocytogenes). Results showed that L. plantarum combined with 2% and 4% (w/v) FOS significantly (p < 0.05) inhibited the growth of L. monocytogenes (3–3.5 log10 CFU/mL reduction) at the incubation temperature of 10 °C and 25 °C. Under the same combination condition, the invasion rates of L. monocytogenes to Caco-2 and BeWo cells were reduced more than 90% compared to the result of the untreated group. After L. plantarum was combined with the 2% and 4% (w/v) FOS treatment, the gene expression of actin-based motility, sigma factor, internalin A, internalin B, positive regulatory factor A, and listeriolysin O significantly (p < 0.05) were reduced over 91%, 77%, 92%, 89%, 79%, and 79% compared to the result of the untreated group, respectively. The inhibition level of the L. plantarum and FOS combination against L. monocytogenes was higher than that of FOS or L. plantarum alone. Overall, these results indicated that the L. plantarum and FOS combination might be an effective formula against L. monocytogenes.

The Impact of Pre- and Probiotic Product Combinations on Ex vivo Growth of Avian Pathogenic Escherichia coli and Salmonella Enteritidis

Due to the global spread of antibiotic resistance, there is a strong demand to replace antimicrobial growth promotors in livestock. To identify suitable additives that inhibit the growth of avian pathogenic Escherichia coli O1/O18 and Salmonella enterica serotype Enteritidis strains, an ex vivo screening was performed. Inulin and fructooligosaccharides (FOS) were investigated as prebiotics. Enterococcus faecium and Bacillus coagulans served as probiotic strains. Firstly, the pathogen was anaerobically incubated in caecal digesta from different broiler breeder flocks with the addition of feed additives. Secondly, subsamples of these suspensions were incubated in an antibiotic medium for selective growth of the pathogen. During this step, turbidity was recorded, and lag times were calculated for each pathogen as readout of growth inhibition. Combinations of E. faecium with inulin or FOS significantly extended the lag time for E. coli compared to control. Moreover, older age was a significant factor to enhance this inhibitory effect. In contrast, the combination of FOS and B. coagulans showed shorter lag times for S. Enteritidis. Our results indicate that the E. faecium strain with prebiotics may inhibit the pathogen proliferation in the studied poultry flocks. Furthermore, our results suggest that prophylactic treatments should be assigned by feed additive, age and animal origin.

Microbial and chemical composition of Cheddar cheese supplemented with prebiotics from pasteurized milk to aging

Microbial and chemical properties of cheese is crucial in the dairy industry to understand their effects on cheese quality. Microorganisms within this fat, protein, and water matrix are largely responsible for physiochemical characteristics and associated quality. Prebiotics can be used as an energy source for lactic acid bacteria in cheese by altering the microbial community and provide the potential for value-added foods, with a more stable probiotic population. This research focuses on the addition of fructooligosaccharides (FOS) or inulin to the Cheddar cheese-making process to evaluate the effects on microbial and physicochemical composition changes. Laboratory-scale Cheddar cheese produced in 2 replicates was supplemented with 0 (control), 0.5, 1.0, and 2.0% (wt/wt) of FOS or inulin using 18 L of commercially pasteurized milk. A total of 210 samples (15 samples per replicate of each treatment) were collected from cheese-making procedure and aging period. Analysis for each sample were performed for quantitative analysis of chemical and microbial composition. The prevalence of lactic acid bacteria (log cfu/g) in Cheddar cheese supplemented with FOS (6.34 ± 0.11 and 8.99 ± 0.46; ± standard deviation) or inulin (6.02 ± 0.79 and 9.08 ± 1.00) was significantly higher than the control (5.84 ± 0.27 and 8.48 ± 0.06) in whey and curd, respectively. Fructooligosaccharides supplemented cheeses showed similar chemical properties to the control cheese, whereas inulin-supplemented cheeses exhibited a significantly higher moisture content than FOS and the control groups. Streptococcus and Lactococcus were predominant in all cheeses and 2% inulin and 2% FOS-supplemented cheeses possessed significant amounts of nonstarter lactic acid bacteria found to be an unidentified group of Lactobacillaceae, which emerged after 90 d of aging. In conclusion, this study demonstrates that prebiotic supplementation of Cheddar cheese results in differing microbial and chemical characteristics.

Fructooligosaccharides (FOS) significantly increased the relative abundance of intestinal B. pseudolongum in mice with different genotypes

Fructooligosaccharides (FOS) promote the proliferation of Bifidobacterium, especially Bifidobacterium pseudolongum in C57BL/6J mice. However, the response of intestinal microbes to FOS is influenced by host genotypes. Therefore, we compared the intestinal microbiota of four commonly used mice before and after FOS intervention, including C57BL/6J, BALB/c, Institute Cancer Research (ICR), and Kunming (KM) mice. The intestinal microbiota of the four genotypes exhibited similarities in composition but differences in relative abundance. Bifidobacterium was significantly increased to different degrees in the four genotypes of mice after FOS intervention, and Akkermansia and Bacteroides were also significantly increased in BALB/c and KM mice. Lactobacillus and Alistipes levels were unchanged or decreased. Within the genus Bifidobacterium, B. pseudolongum was the dominant species in the four genotypes of mice and proliferated significantly after FOS intervention, with dramatic proliferation in C57BL/6J mice (9.49%). Furthermore, eight strains of B. pseudolongum were screened from the feces of mice with four genotypes, and there was a great difference in the ability and manner of utilizing FOS among the strains. The strains from C57BL/6J mice exhibited the strongest utilization of 1-kestose (GF2), whereas other strains could utilize both GF2 and nistose (GF3) weakly. The gut microbial analysis of mice with different genotypes complemented our previous studies. The results provided the background strains of the different mouse genotypes and suggested a correlation between the utilization ability and the response of the strains to FOS. Further studies on the utilization ability of strains and competition in the intestine will contribute to the understanding of the mechanisms of the intestinal microbial response to diet.

Effects of dietary oligosaccharides on serum biochemical index, intestinal morphology, and antioxidant status in broilers.

In order to determine the effect of different oligosaccharides on growth performance, intestinal health, and antioxidant status of broilers, 240 1-day-old XiangHuang broilers were randomly distributed to 4 treatments with 6 replicates each. Birds were fed corn-soybean-based diets (CON), and birds in xylo-oligosaccharides (XOS), fructo-oligosaccharides (FOS), and iso-maltooligosaccharide (IMO) groups were given the basal diet supplemented with 200 mg/kg XOS, FOS, and IMO, respectively. Result showed that average daily gain (ADG) during the whole 5weeks in FOS group was greater than that in control group (p < 0.05). Both breast and thigh muscle percentages were higher for birds fed XOS versus CON (p < 0.05). Oligosaccharides supplementation increased jejunal villus height compared with control group (p < 0.05). Malondialdehyde (MDA) concentration in breast muscle was lower for birds fed diet containing FOS versus CON (p < 0.05). Activities of total superoxide dismutase (T-SOD) in serum and thigh muscle were higher in IMO than in control group (p < 0.05). Serum T-SOD and breast muscle's glutathione peroxidase (GSH-Px) activity was higher in XOS compared with control group (p < 0.05). Conclusion, dietary oligosaccharides such as XOS, FOS, and IMO could improve intestinal health and antioxidant ability of muscle without affect growth performance in broilers.

RETRACTED: Fructooligosaccharides: From Breast Milk Components to Potential Supplements. A Systematic Review

Breast milk is the optimal food choice for infant growth and development. Among breast milk components, fructooligosaccharides (FOSs) are being actively studied because of their role in microbiota development. In particular, 2'-fucosyllactose is being proposed as a potential supplement/nutraceutical or component of infant formula. In this systematic review, we critically summarize the available information on FOSs and we discuss their future use in infant nutrition. We searched the main electronic databases (PubMed, Embase, and Scopus), with a final check in May 2021. Search terms were inserted individually and using the Boolean tools AND and OR. Relevant articles were identified using the following words: ("fructooligosaccharides" OR "FOS") AND ("human milk" OR "breast milk" OR "donor milk" OR "bank milk"). The search retrieved 1814 articles. After removal of duplicates, we screened 1591 articles based on title, abstract, and exclusive use of the English language. We included articles describing the concentration of FOSs in human milk and assessed the relevant ones. We excluded reviews, studies on animals, and studies exclusively carried out on adults. Also, we excluded studies that have not reported evidence either on FOSs or on galactooligosaccharides from human milk. The resulting publications were reviewed, and 10 studies were included in the systematic review. We conclude that human milk FOSs are, indeed, crucial to infant gut development and their addition to infant formula is safe, well-tolerated, and might provide immune benefits to newborns. However, we would like to underscore the scantiness of human data and the need to avoid the immediate translation of infant research to the commercialization of supplements marketed to adults.