Sofia Kolida’s research while affiliated with University of Reading and other places

People with coeliac disease (CD) have a higher risk of developing cardiovascular disease (CVD), potentially due to inflammation. Probiotics can influence CVD risk through several mechanisms including modifying inflammation. We performed a systematic review of probiotic interventions in people with CD. In total, 4 databases were systematically searched for studies published up to March 2023. All outcomes, inclusive of any cardiovascular risk factors, were collated and reported. We screened 8084 articles and 11 publications reporting on 7 RCTs and 2 non-RCTs met the inclusion criteria for qualitative analysis. In total, 1 RCT and both non-RCTs were considered to have a high risk of bias. There was large heterogeneity between the studies and adherence to a gluten-free diet was only measured in two studies. No specific outcomes related to cardiovascular risk were reported. Two studies reported a significant reduction on serum TNF-α in children over time after probiotic supplementation. One study reported no significant change in intestinal permeability over a 3-week intervention. Currently there is insufficient evidence to advocate a positive impact of probiotics on inflammation in CD, due, in part, to the limited data on adherence to the gluten-free diet and active disease.

This study was conducted to investigate the sweetness intensity and the potential fecal microbiome modulation of galactooligosaccharides in combination with enzymatically modified mogrosides (mMV-GOS), both generated through a patented single-pot synthesis. Sweetness intensity was performed in vivo by trained sensory panelists. The impact on the human fecal microbiome was evaluated by in vitro pH-controlled batch fermentation, and bacterial populations and organic acid concentrations were measured by qPCR and GC-FID, respectively. Significant growth (p ≤ 0.05) during the fermentation at 10 h of bacterial populations includes Bifidobacterium (8.49 ± 0.44 CFU/mL), Bacteroides (9.73 ± 0.32 CFU/mL), Enterococcus (8.17 ± 0.42 CFU/mL), and Clostridium coccoides (6.15 ± 0.11 CFU/mL) as compared to the negative control counts for each bacterial group (7.94 ± 0.27, 7.84 ± 1.11, 7.52 ± 0.37, and 5.81 ± 0.08 CFU/mL, respectively) at the same time of fermentation. Likewise, the corresponding significant increase in production of SCFA in mMV-GOS at 10 h of fermentation, mainly seen in acetate (20.32 ± 2.56 mM) and propionate (9.49 ± 1.44 mM) production compared to a negative control at the same time (8.15 ± 1.97 and 1.86 ± 0.24 mM), is in line with a positive control (short-chain fructooligosaccharides; 46.74 ± 12.13 and 6.51 ± 1.91 mM, respectively) revealing a selective fermentation. In conclusion, these substrates could be considered as novel candidate prebiotic sweeteners, foreseeing a feasible and innovative approach targeting the sucrose content reduction in food. This new ingredient could provide health benefits when evaluated in human studies by combining sweetness and prebiotic fiber functionality.

Lactobacillus plantarum ECGC13110402 is a probiotic, selected for its high bile salt hydrolase and cholesterol reducing activity. This parallel, double-blind, placebo-controlled, randomized pilot study, investigated the cholesterol reducing capacity of L. plantarum ECGC13110402 in 16 hypercholesterolemic adults. Participants ingested 4 ×10⁹ CFU encapsulated ECGC13110402 (active; n=8) or placebo (n=8), once daily, over 6 weeks, followed by a 3-week washout. Fasting blood samples were collected for blood lipid, liver function, and vitamin D analysis. After 6 weeks of L. plantarum ECGC 13110402 daily intake, biologically and statistically significant reductions were noted in TC by an average 34.6% (p=0.001), LDL-C by 28.4% (p=0.03), non-HDL-C by 17.6% (p=0.001) and apoB by 28.6% (p=0.008) compared to the placebo. No changes were observed in liver function biomarkers and vitamin D and no adverse effects were noted throughout the study. The findings of this study suggest that L. plantarum ECGC 13110402 can safely improve lipid profiles in dyslipidaemic individuals.

Luo Han Guo fruit extract (Siraitia grosvenorii), mainly composed of mogroside V (50%), could be considered a suitable alternative to free sugars; however, its commercial applications are limited by its unpleasant off-notes. In the present work, a central composite design method was employed to optimize the transglycosylation of a mogroside extract using cyclodextrin glucosyltransferases (CGTases) from three different bacteriological sources (Paenibacillus macerans, Geobacillus sp., and Thermoanaerobacter sp.) considering various experimental parameters such as maltodextrin and mogroside concentration, temperature, time of reaction, enzymatic activity, and pH. Product structures were determined by liquid chromatography coupled to a diode-array detector (LC-DAD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Sensory analysis of glucosylated mogrosides showed an improvement in flavor attributes relevant to licorice flavor and aftereffect. Consequently, an optimum methodology was developed to produce new modified mogrosides more suitable when formulating food products as free sugar substitutes.

To improve flavor profiles, three cyclodextrin glucosyltransferases (CGTases) from different bacteriological sources, Paenibacillus macerans, Geobacillus sp. and Thermoanaerobacter sp., were used with an extract of steviol glycosides (SVglys) and rebaudioside A (RebA) as acceptor substrates in two parallel sets of reactions. A central composite experimental design was employed to maximize the concentration of glucosylated species synthesized, considering temperature, pH, time of reaction, enzymatic activity, maltodextrin concentration and SVglys/RebA concentration as experimental factors, together with their interactions. Liquid chromatography coupled to a diode-array detector (LC-DAD), liquid chromatography-mass spectrometry (LC-ESI-MS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) were used to characterize and identify the chemical structures obtained along the optimization. To assess the impact on the sensory properties, a sensory analysis was carried out with a group of panelists that evaluated up to 16 sensorial attributes. CGTase transglucosylation of the C-13 and/or C-19 led to the addition of up to 11 glucose units to the steviol aglycone, which meant the achievement of enhanced sensory profiles due to a diminution of bitterness and licorice appreciations. The outcome herein obtained supposes the development of new potential alternatives to replace free sugars with low-calorie sweeteners with added health benefits.

An approach that combines weight loss with additional health benefits is very desirable. Glucomannan is a dietary fibre that expands in the stomach, creating the feeling of fullness, while chromium can regulate insulin response. Oligofructose is a non-digestible prebiotic fibre with well-established bifidogenic properties that may also have a role in regulating satiety and systemic inflammation. The aim of this 4-week pilot human intervention was to investigate the effect of agglomerated glucomannan, oligofructose and chromium, as part of a calorie restricted diet plan, on weight loss, satiety, satiation, mood and gut microbiota in 12 females (18–65 years, BMI 25–35 kg/m²). Significant reductions were observed in the anthropometric parameters and systolic blood pressure at the end of trial along with a positive impact on gut microbiota and food cravings. This pilot study suggests that this dietary combination, within an energy restricted, diet may be beneficial in managing obesity related health outcomes.

Levan, a bacterial exopolysaccharide (EPS), has been suggested to have several biological activities, such as anti-tumour activity and lowering blood pressure. There has also been interest in its potential prebiotic activity. This study investigated the fermentation profile of a levan fraction from Erwinia sp. 10119 (average DP = 137) throughout a three-stage continuous gut model system, in which inulin HP (average DP = 40) was included as a comparison. Levan-type fructan was found to selectively stimulate the growth of Bifidobacterium and Eubacterium rectale - Clostridium coccoides group in all fermenter vessels, with significant (p < 0.05) increases in the concentration of both acetate and butyrate. The increases in Bifidobacterium population were significantly (p < 0.05) higher in the models treated with levan-type fructan (0.8–1.24 log cell/mL) compared to the models treated with inulin HP (0.62–0.7 log cell/mL), indicating a stronger bifidogenic effect of levan-type fructan and a prolonged persistence in the colon due to its higher DP.

Copra meal hydrolysate (CMH) is obtained by hydrolyzing defatted copra meal with β-mannanase from Bacillus circulans NT 6.7. In this study, we investigated the resistance of CMH to upper gastrointestinal tract digestion and the fecal fermentation profiles of CMH. Fecal slurries from four healthy human donors were used as inocula, and fructooligosaccharides (FOS) were used as a positive prebiotic control. Fecal batch cultures were performed at 37 °C under anaerobic conditions. Samples were collected at 0, 10, 24 and 34 h for bacterial enumeration via fluorescent in situ hybridization and organic acid (OA) analysis. In vitro gastric stomach and human pancreatic α-amylase simulations demonstrated that CMH was highly resistant to hydrolysis. Acetate was the main fermentation product of all the substrates. The proportions of acetate production of the total OAs from FOS, CMH and yeast mannooligosaccharides (MOS) after 34 h of fermentation did not significantly differ (69.76, 65.24 and 53.93%, respectively). At 24 h of fermentation, CMH promoted the growth of Lactobacillus and Bifidobacterium groups (P < 0.01) and did not significantly differ from the results obtained using FOS. The results of in vitro fecal fermentation of CMH indicate that CMH can promote the growth of beneficial bacteria.

This study investigates the sweetness properties and other sensory attributes of ten commercial and four novel prebiotics (4-galactosyl-kojibiose, lactulosucrose, lactosyl-oligofructosides and raffinosyl-oligofructosides) of high degree of purity and assesses the influence of their chemical structure features on sweetness. The impact of the type of glycosidic linkage by testing four sucrose isomers, as well as the monomer composition and degree of polymerization on sweetness properties were determined. Data from the sensory panel combined with principal component analysis (PCA) concludes that chain length was the most relevant factor in determining the sweetness potential of a carbohydrate. Thus, disaccharides had higher sweetness values than trisaccharides which, in turn, exhibited superior sweetness than mixtures of oligosaccharides having DP above 3. Furthermore, a weak non-significant trend indicated that the presence of a ketose sugar moiety led to higher sweetness. The novel prebiotics tested in this study had between 15 and 25% of relative sweetness, in line with other commercial prebiotics, and samples varied in their extent of off flavour. Therefore, these findings suggest a potential use for clean tasting prebiotics as partial sugar replacers, or in combination with high intensity sweeteners, to provide a well-balanced sweetness profile.