Now showing items 1-20 of 867

    • Human gut homeostasis and regeneration: the role of the gut microbiota and its metabolites

      Arenas-Gómez, Claudia Marcela; Garcia-Gutierrez, Enriqueta; Escobar, Juan S.; Cotter, Paul D.; Marie Skłodowska-Curie grant; Science Foundation Ireland; Department of Agriculture, Food and the Marine; Enterprise Ireland; European Commission; 847402; et al. (Informa UK Limited, 2022-11-11)
      The healthy human gut is a balanced ecosystem where host cells and representatives of the gut microbiota interact and communicate in a bidirectional manner at the gut epithelium. As a result of these interactions, many local and systemic processes necessary for host functionality, and ultimately health, take place. Impairment of the integrity of the gut epithelium diminishes its ability to act as an effective gut barrier, can contribute to conditions associated to inflammation processes and can have other negative consequences. Pathogens and pathobionts have been linked with damage of the integrity of the gut epithelium, but other components of the gut microbiota and some of their metabolites can contribute to its repair and regeneration. Here, we review what is known about the effect of bacterial metabolites on the gut epithelium and, more specifically, on the regulation of repair by intestinal stem cells and the regulation of the immune system in the gut. Additionally, we explore the potential therapeutic use of targeted modulation of the gut microbiota to maintain and improve gut homeostasis as a mean to improve health outcomes.
    • Extraction of plant protein from green leaves: Biomass composition and processing considerations

      Pérez-Vila, Sara; Fenelon, Mark; O'Mahony, James A.; Gómez Gómez-Mascaraque, Laura; Teagasc Walsh Scholarship Programme; 2020032 (Elsevier BV, 2022-12)
      There is an increasing need to explore alternative sources of proteins for food applications. Green leaves contain high levels of the enzyme RuBisCO, representing a source of protein with good functional and nutritional properties. However, the optimal conditions for extraction and purification of RuBisCO at a large scale have not yet been defined. This review discusses the main factors affecting the extraction of proteins from green leaves, from plant composition in terms of protein content and other compounds that affect the yield and quality of extractable protein, to the essential steps and challenges faced during extraction and purification, including considerations for achieving food-grade ingredient status. There are some key factors to consider when developing a protein concentrate for human consumption. The first step is the selection of an optimal raw material; plant tissues are complex matrices that require thorough characterization, including non-protein nitrogen and other undesirable compounds. The effect of the extraction and purification process on functionality, oxidation and proteolytic stability should also be considered. Moreover, the appropriate removal of undesired compounds must be considered to obtain plant protein concentrates suitable for food products.
    • Characteristics of traditional Chinese acidic rice soup (rice-acid) prepared with different fermentation methods

      Liu, Na; Qin, Likang; Pan, Jihong; Miao, Song; National Natural Science Foundation of China; Technology platform and talent team plan of Guizhou; Graduate Research Fund Project of Guizhou; Industry-University-Research Cooperation Project of Guizhou; China Scholarship Council; 32060530; et al. (Elsevier, 2021-11-25)
      Rice-acid, a Chinese traditional acidic rice soup (rice-acid), is widely accepted by consumers due to its unique flavor and anti-oxidation, anti-aging and immunity enhancement functions. This study confirmed that L-lactic acid and malic acid were the main organic acids in rice-acid. Low-temperature rice-acid samples produced by enterprises had the highest signal intensity of sour taste. The total content of free amino acids in different fermented rice-acid samples were in the range of 0.003–0.468 mg/g. 42 key volatile flavor compounds were identified in rice-acid. 8 volatile compounds with a higher contribution to the aroma of rice-acid were respectively acetic acid, 1-octen-3-ol, 2-heptanol, ethyl acetate, propyl propionate, hexanal, nonanal, and 2,3-butanedione. The interaction between lactic acid bacteria (3.00 × 103–7.02 × 106 CFU/mL) and yeasts (5.04 × 104–2.25 × 108 CFU/mL) affected the formation of taste and aroma components in rice-acid. The physicochemical characteristics including titratable acidity, pH, reducing sugars, amino acid nitrogen, gamma-aminobutyric acid showed significant differences between low-temperature fermentation samples and high-temperature fermentation samples. In addition, relationships linking all data through Pearson coefficient correlation were also reported. In summary, the study can be used to improve the quality of rice-acid products.
    • Characterization and gelling properties of a bioactive extract from Ascophyllum nodosum obtained using a chemical-free approach

      Gómez-Mascaraque, Laura G.; Martínez-Sanz, Marta; Martínez-López, Rosalia; Martínez-Abad, Antonio; Panikuttira, Bhavya; López-Rubio, Amparo; Tuohy, Maria G.; Hogan, Sean A.; Brodkorb, Andre; Department of Agriculture, Food and the Marine; et al. (Elsevier, 2021-05-29)
      The bioactivity and gelling properties of a carbohydrate-rich algal extract obtained from locally harvested Ascophyllum nodosum seaweed using a chemical-free approach were investigated for its potential interest in food applications. Physicochemical characterisation and compositional analysis of the extract, using FTIR, biochemical methods and monosaccharide analysis, confirmed the presence of alginates and fucoidans, although the main polysaccharide present in it was laminarin. Significant amounts of phenolic compounds (~9 ​mg phloroglucinol/100 ​mg sample) were also detected. As a result, the extract exhibited good antioxidant activity. It also showed promising prebiotic potential, promoting the growth of beneficial Lactobacillus sp. and Bifidobacteria sp. when compared with commercial prebiotics, but not that of pathogenic bacteria such as E. coli or P. aeruginosa. The gelling properties of the raw extract were explored to optimize hydrogel bead formation by external gelation in CaCl2 solutions. This was enhanced at neutral to alkaline pHs and high extract and CaCl2 concentrations. The mechanical strength, nano- and microstructure of the hydrogel beads prepared under optimised conditions were determined using compression tests, synchrotron small- and wide-angle X-ray scattering (SAXS/WAXS) and scanning electron microscopy (SEM). It was concluded that the raw algal extract at neutral pH had potential for use as a gelling agent, although further enrichment with alginate improved the mechanical properties of the obtained gels. The advantages and disadvantages of applying the non-purified algal extract in comparison with purified carbohydrates are discussed.
    • The potential of non-starter lactic acid bacteria from Cheddar cheese to colonise the gut

      Leeuwendaal, N.; STANTON, CATHERINE; O'Toole, P.W.; Beresford, Tom P.; Teagasc Walsh Fellowship; Science Foundation Ireland; JPI Food Processing for Health; 2014073 (Elsevier, 2021-08-31)
      This study was undertaken to assess the potential of Non-Starter Lactic Acid Bacteria (NSLAB) from Cheddar cheese to survive gastric transit and display probiotic-related traits including bile salt hydrolase activity, the ability to adhere to the gut epithelium and inhibition of enteropathogen binding. Populations of NSLAB, up to 107 CFU/g per cheese were recovered following exposure of cheese to Simulated Stomach Duodenum Passage (SSDP) conditions. A total of 240 isolates were randomly selected from twelve Cheddar cheeses and assessed for probiotic traits. Two strains Lactobacillus paracasei DPC 7150 and Lactobacillus rhamnosus DPC 7102 showed the most probiotic potential. The Lb. paracasei and Lb. rhamnosus strains displayed adhesion rates of 64% and 79%, respectively and inhibited binding of pathogenic Escherichia coli by >20%. This research demonstrates that Cheddar cheese harbours potentially beneficial bacteria, a large portion of which can survive simulated digestion and potentially exhibit health beneficial effects once ingested.
    • Kinetic modelling of ultrasound-assisted extraction of phenolics from cereal brans

      Milićević, Nataša; Kojić, Predrag; Sakač, Marijana; Mišan, Aleksandra; Kojić, Jovana; Perussello, Camila; Banjac, Vojislav; Pojić, Milica; Tiwari, Brijesh K; European Union; et al. (Elsevier, 2021-11-30)
      Cereal brans are by‐products of the milling of cereal grains, which are mainly used as low value ingredients in animal feed. Wheat and oat bran is a rich source of bioactives and phytochemicals, especially phenolic compounds. Within this study, the application of ultrasound (US) technology to assist the extraction of phenolics from oat and wheat bran was investigated (20–45 kHz). Peleg’s mathematical model was used to study the kinetics of ultrasound-assisted extraction (UAE) and subsequent stirring of total phenolic compounds (TPC). The surface morphology of cereal brans after extraction was studied using SEM analysis. The excellent agreement was determined between the values of TPC calculated from Peleg’s mathematical model and actual experimental results. The constant that represents a time required for the initial phenolic concentration to be extracted to one-half of its initial value has been introduced (K1/2). It was shown that the TPC extraction kinetics was dependent only on K1/2 enabling fast kinetics fitting and comparison between extraction rates. Moreover, different values of K1/2 constant could indicate the differences in brans composition and consequently different influence of US pretreatment on these samples.
    • Tannin-rich extracts improve the performance of amidated pectin as an alternative microencapsulation matrix to alginate

      Molino, Silvia; Rufián Henares, José Ángel; Gómez Gómez-Mascaraque, Laura; Teagasc; European Research Commission; University of Granada; N 816303 (Elsevier, 2022-12-31)
      Microencapsulation of tannin extracts through extrusion-gelation method was performed comparing two alternative encapsulation matrices: alginate and amidated pectin. The microstructure of the generated microbeads was studied, as well as their microencapsulation efficiency and release properties. Overall, pectin-based beads performed better than their alginate-based counterparts. This, combined with a greater incorporation of tannins in the feed formulations led to a higher tannin load in the final beads. The best microencapsulation efficiency was given by pectin microbeads loaded with 10% tannin extract (w/w), but the final tannin content could be further increased by adding a 20% (w/w) concentration of the extracts. During a 14-days storage, only a marginal loss of tannins was recorded for pectin-based microbeads. The results reveal that great potential exists in producing pectin-based microbeads in presence of tannins, which allow better loading capacities and improving structural properties, thanks to the interactions between the tannins and the amidated polysaccharide.
    • High-Pressure Processing on Whole and Peeled Potatoes: Influence on Polyphenol Oxidase, Antioxidants, and Glycaemic Indices

      Tsikrika, Konstantina; Muldoon, Aine; O'Brien, Nora, M.; Rai, Dilip; Department of Agriculture, Food and the Marine; 17/F/299 (Multidisciplinary Digital Publishing Institute, 2021-10-13)
      Polyphenol oxidase (PPO) inactivation in five whole and peeled Irish potato cultivars was investigated using high-pressure processing (HPP) at 400 MPa and 600 MPa for 3 min. PPO activity was significantly lower in most of the HPP-treated samples, while the highest PPO inactivation was observed after HPP at 600 MPa. No significant (p > 0.05) changes were observed on the total phenolic content and antioxidant activity of all the HPP-treated potatoes. Regarding individual phenolic acids, chlorogenic acid was decreased significantly (p < 0.05) in all studied varieties with a concomitant increase (p < 0.05) in caffeic and quinic acid. Similarly, ferulic acid was also increased (p < 0.05) in all studied varieties after the HPP treatment, while there was a variation in rutin and 4-coumaric acid levels depending on the cultivar and the sample type. Anthocyanins in the coloured whole potato varieties (i.e., Kerr’s Pink and Rooster), tentatively identified as pelargonidin-O-ferulorylrutinoside-O-hexoside and pelargonidin-O-rutinoside-O-hexoside, also exhibited significantly (p < 0.05) higher levels in the HPP-treated samples as opposed to those untreated. Glycaemic indices of the potatoes treated with HPP did not differ with the corresponding untreated cultivars.
    • Migration of Cefquinome Antibiotic Residues from Milk to Dairy Products

      Di Rocco, Melissa; Scollard, Jonathan; Sayers, Riona; Furey, Ambrose; Danaher, Martin; Jordan, Kieran; Lourenco, Antonio; Department of Agriculture, Food, and the Marine; 13/F/484 (Multidisciplinary Digital Publishing Institute, 2021-11-19)
      The aim of this study was to investigate the distribution of cefquinome in different dairy products during the processing of naturally contaminated milk or spiked milk. The analysis of cefquinome residues in milk, skimmed milk, buttermilk, whey, cream, butter, curd, and cheese samples was performed using a water:acetonitrile solvent extraction and C18 dispersive solid-phase extraction (d-SPE) clean-up, followed by ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC–MS/MS) determination. The target concentration of cefquinome was achieved in the spiked milk (100 µg kg−1). During its processing, the antibiotic migrated primarily with the skimmed milk as opposed to cream (ratios of 3.6:1 and 2.8:1 for experiments A and B, respectively), and with the buttermilk during butter manufacture (ratios of 6.9:1 and 4.6:1), but was equal in the curd and whey during the manufacture of cheese. In the milk collected from treated animals, the measured concentration of cefquinome was considerably high (approx. 5000 µg kg−1). The results obtained from the dairy products were similar to those obtained in the spiked study (ratios of 8.2:1 and 3.1:1 for experiments A and B, respectively, during the separation of skimmed milk and cream; 6.0:1 and 5.0:1 for A and B, respectively, during the separation of buttermilk and butter). However, during cheesemaking, cefquinome migrated with the whey after cutting the curd, with ratios of 0.54:1 and 0.44:1 for experiments A and B, respectively. The difference in the migration of cefquinome between curd and whey in spiked and animal studies is probably due to the different concentration levels in the two different experiments. The results of this study showed that, in dairy products manufactured from milk containing cefquinome residues, the drug migrated primarily with the high-water-containing fractions.
    • Rehydration Properties of Whey Protein Isolate Powders Containing Nanoparticulated Proteins

      Guralnick, Jacob R.; Panthi, Ram R.; Cenini, Valeria L.; Mishra, Vinay S. N.; O’Hagan, Barry M. G.; Crowley, Shane V.; O’Mahony, James A.; Irish Department of Agriculture, Food and the Marine; Department of Agriculture, Environment and Rural Affairs in Northern Ireland; DAIRYDRY 15-F-679 (Multidisciplinary Digital Publishing Institute, 2021-10-27)
      The rehydration properties of original whey protein isolate (WPIC) powder and spray-dried WPI prepared from either unheated (WPIUH) or nanoparticulated WPI solutions were investigated. Nanoparticulation of whey proteins was achieved by subjecting reconstituted WPIC solutions (10% protein, w/w, pH 7.0) to heat treatment at 90 °C for 30 s with no added calcium (WPIH) or with 2.5 mM added calcium (WPIHCa). Powder surface nanostructure and elemental composition were investigated using atomic force microscopy and X-ray photoelectron spectroscopy, followed by dynamic visualisation of wetting and dissolution characteristics using environmental scanning electron microscopy. The surface of powder particles for both WPIUH and WPIC samples generally appeared smooth, while WPIH and WPIHCa displayed micro-wrinkles with more significant deposition of nitrogen and calcium elements. WPIH and WPIHCa exhibited lower wettability and solubility performance than WPIUH and WPIC during microscopic observation. This study demonstrated that heat-induced aggregation of whey proteins, in the presence or absence of added calcium, before drying increases aggregate size, alters the powder surface properties, consequently impairing their wetting characteristics. This study also developed a fundamental understanding of WPI powder obtained from nanoparticulated whey proteins, which could be applied for the development of functional whey-based ingredients in food formulations, such as nanospacers to modulate protein–protein interactions in dairy concentrates.
    • Changes to the Oligosaccharide Profile of Bovine Milk at the Onset of Lactation

      Quinn, Erin M.; O'Callaghan, Tom F.; T. Tobin, John; Murphy, John Paul; Sugrue, Katie; Slattery, Helen; O'Donovan, Michael; Hickey, Rita M.; Teagasc (Multidisciplinary Digital Publishing Institute, 2020-12-01)
      Numerous bioactive components exist in human milk including free oligosaccharides, which represent some of the most important, and provide numerous health benefits to the neonate. Considering the demonstrated value of these compounds, much interest lies in characterising structurally similar oligosaccharides in the dairy industry. In this study, the impacts of days post-parturition and parity of the cows on the oligosaccharide and lactose profiles of their milk were evaluated. Colostrum and milk samples were obtained from 18 cows 1–5 days after parturition. Three distinct phases were identified using multivariate analysis: colostrum (day 0), transitional milk (days 1–2) and mature milk (days 3–5). LS-tetrasaccharide c, lacto-N-neotetraose, disialyllacto-N-tetraose, 3’-sial-N-acetyllactosamine, 3’-sialyllactose, lacto-N-neohexaose and disialyllactose were found to be highly affiliated with colostrum. Notably, levels of lactose were at their lowest concentration in the colostrum and substantially increased 1-day post-parturition. The cow’s parity was also shown to have a significant effect on the oligosaccharide profile, with first lactation cows containing more disialyllacto-N-tetraose, 6’-sialyllactose and LS-tetrasaccharide compared to cows in their second or third parity. Overall, this study identifies key changes in oligosaccharide and lactose content that clearly distinguish colostrum from transitional and mature milk and may facilitate the collection of specific streams with divergent biological functions.
    • Lactobacillus rhamnosus GG soluble mediators ameliorate early life stress-induced visceral hypersensitivity and changes in spinal cord gene expression

      McVey Neufeld, Karen-Anne; Strain, Conall R.; Pusceddu, Matteo M.; Waworuntu, Rosaline V.; Manurung, Sarmauli; Gross, Gabriele; M. Moloney, Gerry; Hoban, Alan E.; Murphy, Kiera; STANTON, CATHERINE; et al. (Portland Press Ltd., 2020-11-23)
      Visceral hypersensitivity is a hallmark of many functional and stress-related gastrointestinal disorders, and there is growing evidence that the gut microbiota may play a role in its pathophysiology. It has previously been shown that early life stress-induced visceral sensitivity is reduced by various probiotic strains of bacteria (including Lactobacillus rhamnosus GG (LGG)) alone or in combination with prebiotic fibres in rat models. However, the exact mechanisms underpinning such effects remain unresolved. Here, we investigated if soluble mediators derived from LGG can mimic the bacteria’s effects on visceral hypersensitivity and the microbiota–gut–brain axis. Rats were exposed to maternal separation (MS) from postnatal days 2–12. From weaning onwards both non-separated (NS) and MS offspring were provided drinking water with or without supplementation of standardized preparations of the LGG soluble mediators (LSM). Our results show that MS led to increased visceral sensitivity and exaggerated corticosterone plasma levels following restraint stress in adulthood, and both of these effects were ameliorated through LSM supplementation. Differential regulation of various genes in the spinal cord of MS versus NS rats was observed, 41 of which were reversed by LSM supplementation. At the microbiota composition level MS led to changes in beta diversity and abundance of specific bacteria including parabacteroides, which were ameliorated by LSM. These findings support probiotic soluble mediators as potential interventions in the reduction of symptoms of visceral hypersensitivity.
    • The gut microbiome influences the bioavailability of olanzapine in rats

      Cussotto, Sofia; Walsh, Jacinta; Golubeva, Anna V.; Zhdanov, Alexander V.; Strain, Conall R.; Fouhy, Fiona; STANTON, CATHERINE; Dinan, Timothy G.; Hyland, Niall P.; Clarke, Gerard; et al. (Elsevier BV, 2021-03-11)
      Background: The role of the gut microbiome in the biotransformation of drugs has recently come under scrutiny. It remains unclear whether the gut microbiome directly influences the extent of drug absorbed after oral administration and thus potentially alters clinical pharmacokinetics. Methods: In this study, we evaluated whether changes in the gut microbiota of male Sprague Dawley rats, as a result of either antibiotic or probiotic administration, influenced the oral bioavailability of two commonly prescribed antipsychotics, olanzapine and risperidone. Findings: The bioavailability of olanzapine, was significantly increased (1.8-fold) in rats that had undergone antibiotic-induced depletion of gut microbiota, whereas the bioavailability of risperidone was unchanged. There was no direct effect of microbiota depletion on the expression of major CYP450 enzymes involved in the metabolism of either drug. However, the expression of UGT1A3 in the duodenum was significantly downregulated. The reduction in faecal enzymatic activity, observed during and after antibiotic administration, did not alter the ex vivo metabolism of olanzapine or risperidone. The relative abundance of Alistipes significantly correlated with the AUC of olanzapine but not risperidone. Interpretation: Alistipes may play a role in the observed alterations in olanzapine pharmacokinetics. The gut microbiome might be an important variable determining the systemic bioavailability of orally administered olanzapine. Additional research exploring the potential implication of the gut microbiota on the clinical pharmacokinetics of olanzapine in humans is warranted.
    • Shared and non-shared sIgA-coated and uncoated bacteria in intestine of mother-infant pairs

      Ding, Mengfan; Chen, Haiqin; Yu, Renqiang; Ross, R. Paul; STANTON, CATHERINE; Zhang, Hao; Yang, Bo; Chen, Wei; National Key R&D Program of China; National Natural Science Foundation of China; et al. (Research Square Platform LLC, 2022-04-20)
      Background The infant gut microbiota is critical for promoting and maintaining early life health. Bacteria coated by secretory immunoglobulin A (sIgA) may help commensal bacteria colonize the gastrointestinal tract. The study aimed to analyze the composition of sIgA-coated and sIgA-uncoated bacterial communities at genus level, and lactobacilli and bifidobacterial communities at species level in human breast milk (HBM), infant, and maternal feces. Results Eleven pregnant women were recruited successfully. HBM, infant feces during colostrum, transition, and mature stages, and maternal feces within the mature stage were collected. sIgA-coated and sIgAuncoated bacteria were separated with magnetic-activated cell sorting. Then 16S rRNA sequencing, bifidobacterial groEL gene sequencing, and lactobacilli groEL gene sequencing were performed to analyze the bacterial community. The richness of sIgA-coated bacteria was significantly higher than that of sIgA-uncoated bacteria in HBM. PCoA revealed that the compositions of sIgA-coated and sIgAuncoated bacteria were different among HBM, infant and maternal feces. The dominant sIgA-coated bacteria in those samples were Escherichia/shigella and the dominant sIgA-uncoated bacteria was Pseudomonas. Higher relative abundance of sIgA-uncoated Bifidobacterium was found in the three lactation stages in infant feces compared to the corresponding HBM, and a higher relative abundance of sIgA-uncoated Faecalibacterium was found in maternal feces compared to HBM and infant feces. For the bifidobacterial community, PCoA analysis revealed a significantly different Bifidobacterium composition only in the sIgA-uncoated segments of infant feces and maternal feces. sIgA-coated and sIgA-uncoated B. longum subsp. infantis and B. pseudocatenulatum was dominant in infant feces and maternal feces, respectively. Additionally, the relative abundance of sIgA-uncoated B. longum subsp. infantis was significantly higher in infant feces compared to that in maternal feces. For the Lactobacillus community, the composition was significantly different in infant and maternal feces, while at species level, L. paragasseri and L. mucosae were dominant in infant and maternal feces, respectively. Conclusion HBM, infant, and maternal feces showed distinct diversity and composition of both sIgA-coated and sIgAuncoated bacteria at genus level. Infant and maternal feces showed similar diversity and similar composition of Bifidobacterium at species level. The same Bifidobacterium species could be detected both in sIgA-coated and sIgA-uncoated form
    • Bifidobacterium longum counters the effects of obesity: Partial successful translation from rodent to human

      Schellekens, Harriët; Torres-Fuentes, Cristina; van de Wouw, Marcel; Long-Smith, Caitriona M.; Mitchell, Avery; Strain, Conall; Berding, Kirsten; Bastiaanssen, Thomaz, F. S.; Rea, Kieran; Golubeva, Anna V.; et al. (Elsevier, 2021-01-31)
      BackgroundThe human gut microbiota has emerged as a key factor in the development of obesity. Certain probiotic strains have shown anti-obesity effects. The objective of this study was to investigate whether Bifidobacterium longum APC1472 has anti-obesity effects in high-fat diet (HFD)-induced obese mice and whether B. longum APC1472 supplementation reduces body-mass index (BMI) in healthy overweight/obese individuals as the primary outcome. B. longum APC1472 effects on waist-to-hip ratio (W/H ratio) and on obesity-associated plasma biomarkers were analysed as secondary outcomes. MethodsB. longum APC1472 was administered to HFD-fed C57BL/6 mice in drinking water for 16 weeks. In the human intervention trial, participants received B. longum APC1472 or placebo supplementation for 12 weeks, during which primary and secondary outcomes were measured at the beginning and end of the intervention. FindingsB. longum APC1472 supplementation was associated with decreased bodyweight, fat depots accumulation and increased glucose tolerance in HFD-fed mice. While, in healthy overweight/obese adults, the supplementation of B. longum APC1472 strain did not change primary outcomes of BMI (0.03, 95% CI [-0.4, 0.3]) or W/H ratio (0.003, 95% CI [-0.01, 0.01]), a positive effect on the secondary outcome of fasting blood glucose levels was found (-0.299, 95% CI [-0.44, -0.09]). InterpretationThis study shows a positive translational effect of B. longum APC1472 on fasting blood glucose from a preclinical mouse model of obesity to a human intervention study in otherwise healthy overweight and obese individuals. This highlights the promising potential of B. longum APC1472 to be developed as a valuable supplement in reducing specific markers of obesity. FundingThis research was funded in part by Science Foundation Ireland in the form of a Research Centre grant (SFI/12/RC/2273) to APC Microbiome Ireland and by a research grant from Cremo S.A.
    • Comparison of lactose free and traditional mozzarella cheese during shelf-life by aroma compounds and sensory analysis

      Condurso, Concetta; Tripodi, Gianluca; Merlino, Maria; Prestia, Ottavia; STANTON, CATHERINE; Verzera, Antonella; Italian Ministry for Education, University and Research; AIM 1823923-3 - CUP J44I18000190006 (Elsevier, 2021-04-30)
      Aroma compounds and sensory features of lactose free (LFM) and traditional (TM) Mozzarella cheese have been investigated during their labeled shelf-life. Acetoin and 2-heptanone characterized both types of cheese at the production time. During the shelf-life, a statistically significant increase in the amount of the volatiles coming from amino acid and fatty acid metabolism occurred in the LFM samples after 8 days of storage and, to a lesser extent, in TM cheese after 13 days of storage. As regard sensory analysis, milk odor and milk flavor descriptors characterized TM and LFM in the early stage of their shelf-life; bitter and acid taste and yoghurt odor descriptors characterized LFM after 8 days and TM after 13 days. The differences between the two cheese types can be attributed to the proteolytic activity of the lactase enzyme. As a result, the volatile aroma profile and the sensory quality should be taken into account for a proper shelf-life definition of Mozzarella cheese and a shorter shelf-life should be suggested for LFM than TM cheese.
    • Assessing the ability of nisin A and derivatives thereof to inhibit gram-negative bacteria from the genus Thermus

      Jonnala, Bhagya R. Yeluri; Feehily, Conor; O'Connor, Paula M.; Field, Des; Hill, Colin; Ross, R Paul; McSweeney, P.L.H.; Sheehan, Diarmuid (JJ); Cotter, Paul D; Teagasc Walsh Fellowship Programme; et al. (Elsevier, 2021-03-31)
      Nisin is a bacteriocin that is globally employed as a biopreservative in food systems to control gram-positive, and some gram-negative, bacteria. Here we tested the bioactivity of nisin A-producing Lactococcus lactis NZ9700 and producers of bioengineered variants thereof against representatives of the gram-negative genus Thermus, which has been associated with the pink discoloration defect in cheese. Starting with a total of 73 nisin variant-producing Lactococcus lactis, bioactivity against Thermus was assessed via agar diffusion assays, and 22 variants were found to have bioactivity greater than or equal to that of the nisin A-producing control. To determine to what extent this enhanced bioactivity was attributable to an increase in specific activity, minimum inhibitory concentrations were determined using the corresponding purified form of these 22 nisin A derivatives. From these experiments, nisin M17Q and M21F were identified as peptides with enhanced antimicrobial activity against the majority of Thermus target strains tested. In addition, several other peptide variants were found to exhibit enhanced specific activity against a subset of strains.
    • Improvements in sleep indices during exam stress due to consumption of a Bifidobacterium longum

      Moloney, Gerard M.; Long-Smith, Caitriona M.; Murphy, Amy; Dorland, Danielle; Hojabri, Sara Firuzeh; Ramirez, Loreto Olavarría; Marin, David Campos; Bastiaanssen, Thomaz, F. S.; Cusack, Anne-Marie; Berding, Kirsten; et al. (Elsevier, 2021-01-31)
      Targeting the gut microbiome as an effective therapeutic strategy for psychological disorders has shown promise in recent years. Variation in the composition of the microbiota and restoration of a stable microbiome using targeted interventions (psychobiotics) including Bifidobacteria have shown promise in pre-clinical studies, but more human data is required on the potential health benefits of these live microorganisms. Bifidobacterium including Bif. longum 1714 has been shown to dampen the effects of acute stress in humans. However, its effects over a period of prolonged stress have not been examined. A randomised, placebo-controlled, repeated measures, cross-over intervention study was conducted to examine the effects of a probiotic intervention on measures of stress, cognitive performance, and mood in healthy human volunteers. Twenty male students participated in this crossover study. Post-intervention assessments took place during the university exam period, which was used as a naturalistic chronic stressor. Self-reported measures of stress, depression, sleep quality, physical activity, gastrointestinal symptoms, cognition, and mood were assessed by questionnaire. In addition, tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were administered to all participants. Stress and depression scores increased in both placebo and probiotic treated groups during the exam period. While overall sleep quality and duration of sleep improved significantly in the probiotic treated group during exam stress compared with the placebo treated group, B. longum 1714, similar to placebo treatment, showed no efficacy in improving measures of working memory, visual memory, sustained attention or perception. Overall, while B. longum 1714 shows promise in improving sleep quality and duration, it did not alleviate symptoms of chronic stress, depression, or any measure of cognitive assessment. Thus, further mechanistic studies into the ability of B. longum 1714 to modulate sleep during prolonged periods of stress are now warranted.
    • Influence of particle size on the physicochemical properties and stickiness of dairy powders

      Haque, Md Kamrul; Kennedy, Deirdre; Laffir, Fathima R.; Hogan, Sean; O'Mahony, James A.; Murphy, Eoin G.; Enterprise Ireland; TC/2014/0016 (Elsevier, 2019-11-30)
      The compositional and physicochemical properties of different whey permeate (WPP), demineralised whey (DWP) and skim milk powder (SMP) size fractions were investigated. Bulk composition of WPP and DWP was significantly (P < 0.05) influenced by powder particle size; smaller particles had higher protein and lower lactose contents. Microscopic observations showed that WPP and DWP contained both larger lactose crystals and smaller amorphous particles. Bulk composition of SMP did not vary with particle size. Surface composition of the smallest SMP fraction (<75 μm) showed significantly lower protein (−9%) and higher fat (+5%) coverage compared with non-fractionated powders. For all powders, smaller particles were more susceptible to sticking. Hygroscopicity of SMP was not affected by particle size; hygroscopicity of semi-crystalline powders was inversely related to particle size. This study provides insights into differences between size fractions of dairy powders, which can potentially impact the sticking/caking behaviour of fine particles during processing.
    • Fate of beta-glucan, polyphenols and lipophilic compounds in baked crackers fortified with different barley-milled fractions

      O'Shea, Norah; Brunton, Nigel P.; Gallagher, Eimear; Harrison, Sabine M.; Rai, Dilip; Department of Agriculture, Food and Marine; FIRM 11/SF/317 (Elsevier, 2019-11-30)
      Four types of crackers were prepared, whereby wheat flour was substituted with different percentages of barley flour and bran. These formulations were compared to a 100% wheat flour (control) cracker with respect to β-glucan, polyphenols and lipophilic bioactives. Incorporation of barley fractions enriched the β-glucan, and phenolic content, as well as in vitro antioxidant capacities of the crackers. However, some polyphenols including procyanidin C and ferulic acid could not be detected in the crackers owing to the probable degradation of these compounds during baking. The β-glucan, flavanols (catechin and procyanidin B), as well as fatty acids and sterols were least affected; while the α-tocotrienols showed degradation following the baking process. Overall, barley fractions can serve as valued ingredients for enhancing the health-salutary components of fortified crackers or the products thereof.